Background: Machine learning, a subset of artificial intelligence, enables large language models (LLMs) like ChatGPT and Gemini to analyze data, learn from context, and generate responses without explicit programming. While machine learning and LLMs show promise in orthopedic image analysis and patient education, it is unclear whether LLMs provide accurate responses to patient queries. Methods: Our purpose was to evaluate the alignment of ChatGPT and Gemini’s recommendations for managing glenohumeral arthritis with the American Academy of Orthopaedic Surgeons (AAOS) Evidence-Based Clinical Practice Guidelines (CPGs). Both ChatGPT and Gemini were asked questions based on strong- or moderate-strength recommendations from the AAOS CPG on management of glenohumeral arthritis. Responses were classified by 2 independent reviewers as “agree,” “neutral,” or “disagree” based on their alignment with the CPG recommendations. A Cohen's kappa coefficient was used to assess interobserver reliability, and Fisher's exact test was used to compare the accuracy of responses between LLMs. Results: Of the 12 recommendations of strong- or moderate-strength evidence, ChatGPT and Gemini provided responses that were in agreement for 6 (50%) and 9 (75%) of recommendations, respectively. There were no significant differences in performance between ChatGPT and Gemini. ChatGPT provided 6 study references, of which 4 were nonexistent or inappropriately cited. Gemini provided 32 study references, of which 5 studies were nonexistent or inappropriately cited. Conclusion: Both ChatGPT and Gemini do not consistently provide responses that align with the AAOS CPG for management of glenohumeral arthritis. Responses frequently included confabulated details or inappropriately referenced articles. Consequently, physicians and patients should use these artificial intelligence platforms with caution when seeking advice on management of glenohumeral arthritis.

Objective: Biomechanical studies indicate that tibial inlay (TI) posterior cruciate ligament (PCL) reconstruction avoids the 'killer turn,' which may reduce graft friction and elongation compared with transtibial (TT) reconstruction. However, clinical differences in posterior stability and function remain inconsistent, and complication rates vary, particularly in cases involving multiligament injuries. Technological advancements have enabled arthroscopic TI procedures to be performed in the supine position, yet there are few comparative studies between arthroscopic TI and TT techniques. Additionally, given the relative infrequency and injury complexity associated with PCL reconstructions, outcome differences may be difficult to discern. To address these gaps, this study was designed to determine whether technique-related advantages persist after balancing baseline risk using an outcome-first framework. We hypothesized that after propensity score matching (PSM), TI PCL reconstruction would demonstrate equal posterior stability without higher complication rates compared with TT. Methods: This was an IRB-approved, retrospective cohort study at a single academic system. Consecutive TI cases over a ten-year period with >= 12-week follow-up were included; TT controls were randomly sampled from the same surgery-date window to limit era effects. We excluded cases with inadequate follow-up, revision surgery, and missing key covariates. Propensity scores were estimated using a logistic regression model including age, BMI, sex, nicotine use, substance abuse history, pre-injury sport participation, occupation (manual, non-manual, not employed, unknown), vascular injury, pre-operative nerve injury, and Schenck injury classification (non-bicruciate PCL, KD2, KD3/4, KD5). Patients undergoing transtibial (TT) versus tibial inlay (TI) PCL reconstruction were matched 2:1 using nearest neighbor matching without replacement and a caliper width of 0.20 of the standard deviation of the logit of the propensity score. Covariate balance was evaluated using standardized mean differences (SMDs), with values <0.1 considered excellent and <0.2 considered acceptable. Matched comparisons used Welch's t-tests (continuous) and Fisher's exact tests (categorical); two-sided α=0.05. Absolute differences and 95% CIs were utilized to support clinical interpretation. The primary outcome was posterior drawer grade at the latest follow-up. Secondary outcomes included postoperative complications, knee flexion (degrees), return to sport (RTS), and return to work (RTW). Results: Of 197 eligible patients, 137 met exclusion and inclusion criteria. After matching, 82 patients were analyzed (50 TT, 32 TI), with post-match balance (max SMD <= [0.15]; Love plot Figure 1 and baseline characteristics Table 1 provided). Mean follow-up was TT 62.1 weeks (12-416) and TI 50.9 weeks (13-242). For the primary outcome (posterior drawer stability grade), TT had 33 grade I (66%), 17 grade II (34%); TI had 29 grade I (91%), 3 grade II (9%). TI achieved Grade I stability in 90.6% vs 66.0% for TT (Δ +24.6%, 95% CI +5.6% to +51.6%, p=0.016)(Figure 2). Overall complication rates were not statistically different (TT 19% vs TI 18%, p=>0.999). The distribution of complications differed, with arthrofibrosis observed more frequently in TI cases (4/32, 13%) and graft insufficiency only in TT (3/50, 6%), although neither comparison reached significance (Figure 3). Flexion was similar between patients (TT 124 vs TI 127 degrees, p = 0.364). The RTW rates among those employed preinjury were similar: 22/26 TT (84.6%) vs 12/15 TI (80.0%; p=0.693). The RTS rates among preinjury athletes were similar: 13/16 TT (81.3%) vs 13/14 TI (92.9%; p=0.602). Conclusions: In this PSM-balanced retrospective cohort study, arthroscopic TI reconstruction showed superior posterior stability without higher complication rates compared with TT. RTW and RTS were comparable. These data support TI as a reasonable, outcome-focused option for PCL reconstruction. Future prospective, multi-center studies with standardized stability measures and longer follow-up are warranted.

Objectives: Quadriceps weakness is common after anterior cruciate ligament (ACL) injuries and reconstruction (ACLR). Blood flow restriction (BFR) therapy is being increasingly used during ACLR rehabilitation to facilitate a hypoxic environment that triggers a local response for muscle strengthening and hypertrophy, while minimizing stress on the ACL graft. However, there are inconsistent or lacking data on the outcomes of BFR in this setting. The purpose of this study was to investigate changes in quadriceps muscle strength between conventional ACLR rehabilitation plus early (from 2-8 weeks postoperative) BFR therapy versus conventional ACLR rehabilitation with sham BFR therapy. We additionally sought to compare the effects of early BFR versus sham BFR therapy on late-stage functional performance, movement biomechanics, and patient-reported outcomes. Methods: Twenty-seven individuals with a unilateral isolated ACLR were randomized to receive 200-minutes of BFR or sham BFR (“CON”) training as part of their ACLR rehabilitation protocol from postoperative weeks 2 through 8. All physical therapy sessions were provided by 7 licensed physical therapists at an academic center (Figure 1). Primary measurements of quadriceps strength were taken via hand-held dynamometer by a blinded observer at 8- and at 36-weeks postoperatively, and limb symmetry indices (LSI) were calculated. Magnetic resonance images (MRI) were acquired of the bilateral knees preoperatively and after 8 weeks of BFR or CON training and evaluated for muscle volume and adipose composition. Single-leg hop testing LSI (6-meter, distance hop, and triple hop) and patient-reported outcomes (International Knee Documentation Committee and Knee Injury and Osteoarthritis Outcome Scores) were compared between groups at 36-weeks postoperatively. Using effect size from existing literature on the effect of BFR on quadriceps strength, we calculated that 12 participants were required in each group for adequate power. Results: At 8-weeks and 36- weeks postoperatively, there were no significant differences between BFR and CON groups for the primary outcome of quadriceps LSI (Table 1). Both groups significantly increased quadriceps and hamstring LSI over time. No significant differences in adipose composition or muscle volume were observed for the either group, in either limb, between pre- and 8 week postoperative MRI. There were additionally no differences between functional hop testing or patient-reported outcomes between the two groups at the 36-week postoperative timepoint. Conclusions: In this randomized controlled trial, addition of early (postoperative weeks 2-8) BFR to standard ACLR rehabilitation protocols resulted in no difference between groups for the primary outcome of quadriceps strength at 8- and 36-weeks postoperatively. Adipose composition, muscle volume, hamstring strength, functional testing, and patient-reported outcome measures were similar between groups at the tested time intervals.

BACKGROUND AND PURPOSE:The ability of large language models (LLMs) such as ChatGPT and Gemini to respond accurately to sports surgery-related patient questions remains unknown. This study aimed to compare the responses of ChatGPT and Gemini regarding anterior cruciate ligament (ACL) and meniscal injuries with the American Academy of Orthopaedic Surgeons (AAOS) Evidence-Based Clinical Practice Guidelines (CPGs) recommendations. METHODS:We queried ChatGPT and Gemini with questions based on statements from the AAOS CPGs for ACL and meniscus injuries. Responses were classified by two reviewers as "Agree," "Neutral," or "Disagree" with the AAOS CPGs. A Cohen's kappa coefficient was used to assess interrater reliability, and chi-squared analyses were used to compare responses between LLMs. RESULTS:Of the 11 CPG recommendations that were of strong or moderate strength, ChatGPT and Gemini provided responses that were in agreement for 9 (82%) and 8 (73%) of recommendations, respectively. While both LLMs showed perfect concordance with the meniscus CPGs, there were no significant differences when comparing the ACL responses or when comparing the LLMs' responses to strong and moderate recommendation queries. ChatGPT provided zero study references, whereas Gemini provided 25 PubMed resources, of which 23 appropriately supported the claims made in the Gemini responses. CONCLUSIONS:While there is still room for growth and transparency in these large language models, providers can expect that these AI platforms generally provide information to patients that aligns with lower extremity sports surgery clinical practice guidelines.

BACKGROUND:Quadriceps weakness is common after anterior cruciate ligament (ACL) injuries and ACL reconstruction (ACLR). Blood flow restriction (BFR) training is being increasingly used during ACLR rehabilitation protocols to facilitate a hypoxic cellular environment that triggers a local stress response theorized to promote muscle hypertrophy, and thus muscle strength, without mechanically loading a healing ACL graft. While BFR is a popular addition to therapy, scientific methods used to examine BFR training following ACLR have been inconsistent or insufficient to determine whether early BFR has a significant therapeutic effect on strength and function, and few studies have used advanced imaging to assess changes in muscle volume and composition. PURPOSE:This study aimed to investigate changes in postoperative quadriceps strength and muscle volume between conventional ACLR rehabilitation with early BFR training and conventional ACLR rehabilitation with sham (e.g., non-therapeutic pressure) BFR training. We secondarily sought to evaluate the effect of early BFR training on late-stage functional and patient-reported outcomes (PROMs). METHODS:Ten individuals with a unilateral isolated ACLR were randomized to receive 200 minutes of BFR or sham (CON) training as part of their ACLR rehabilitation protocol. Quadriceps and hamstring strength were taken via a handheld dynamometer to calculate limb symmetry indices (LSI) at eight and 36 weeks postoperatively. Magnetic resonance (MR) images were acquired of the bilateral knees pre- and post-BFR or CON training and evaluated for muscle volume and adipose composition. Single-leg hop tests were performed at the conclusion of the rehabilitation protocol around 36 weeks postoperatively. PROM measures were measured by the International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS) at baseline and eight and 36 weeks postoperatively. RESULTS:At eight weeks postoperatively, there was not a significant difference in quadriceps and hamstring LSI between the BFR and CON groups. At 36 weeks postoperatively, there was a significant increase in strength within all groups, but there were no significant differences in the improvement of either quadriceps or hamstring strength between the BFR and CON groups. There was no significant change in quadriceps intramuscular adipose composition or muscle volume between pre- and post-BFR MR images within the BFR group. There was additionally no difference between PROMs and adverse events between the two groups at the eight- and 36-week postoperative time points, and there were no complications with early BFR use. CONCLUSION:In this pilot study, quadriceps and hamstring strength, muscle volume, and intramuscular adipose were not impacted over time or between the BFR and standard-of-care groups. Early BFR utilization had no effect on PROMs between BFR and standard of care as measured by IKDC and KOOS. Larger studies are needed to better understand the potential effects of early BFR on patient rehabilitation after ACLR.

Background: In young athletes with anterior cruciate ligament (ACL) injury, increased times from injury to magnetic resonance imaging (MRI) and injury to surgery can lead to the accrual of new injuries over time. Purpose: To determine the patient characteristics associated with differences in timing between injury, MRI, and surgery in young athletes with ACL tears. Study Design: Case-control study; Level of evidence, 3. Methods: We reviewed the electronic medical records of patients aged 13 to 25 years who underwent isolated primary ACL reconstruction between January 2017 and June 2020 at a single orthopaedic surgery department. The times from injury to MRI, MRI to surgery, and injury to surgery were documented. Patient demographic data (age, sex, body mass index [BMI], race and ethnicity, and insurance type) were recorded. Multivariable analysis was used to determine if any patient characteristic had a significant association with increased time to MRI or surgery. Results: A total of 369 patients (mean age, 18.0 years; 56% female) were included. Both age and BMI were found to be significantly associated with timing of care while holding all other predictors constant. For every 1-year increase in patient age, time from injury to MRI increased by 9.6 days (95% CI, 1.8-17.4 days; P = .02), time from MRI to surgery increased by 7.4 days (95% CI, 4.4-10.5 days; P < .001), and time from injury to surgery increased by 17.0 days (95% CI, 8.4-25.6 days; P < .001). Compared with patients with normal BMI, overweight patients (BMI range, 25-29.9 kg/m2) had an MRI-to-surgery time that was on average 37.2 days (95% CI, 11.7-62.7 days; P < .004) longer and an injury to surgery time that was on average 71.8 days (95% CI, 0.5-143.0 days; P = .048) longer. Obese patients (BMI ≥30 kg/m2) did not demonstrate a significant relationship with the studied time intervals. Conclusion: Increasing age and elevated BMI were found to be associated with increased time to MRI and surgical care in young athletes with ACL injuries.

Background: Hamstring strains are common among elite athletes, but their effect on return to the same level of play in American football has been incompletely characterized. Purpose: Data on National Collegiate Athletics Association Division I college football players with acute hamstring strains were gathered to identify the effects these injuries have on both return to play and athletic performance regarding velocity, workload, and acceleration. Study Design: Case Series; Level of evidence, 4. Methods: Injury data for a single Division I football team were prospectively recorded over a 4-year period. Players wore global navigation satellite system and local positioning system (GNSS/LPS) devices to record movement data in practices and games. The practice and game data were cross-referenced to evaluate players with isolated acute hamstring strains. Comparisons were made regarding players’ pre- and postinjury ability to maintain high velocity (>12 mph [19.3 kph]), maximal velocity, triaxial acceleration, and inertial movement analysis (IMA). There were 58 hamstring injuries in 44 players, of which 25 injuries from 20 players had GNSS/LPS data. Results: Players were able to return to play from all 25 injury incidences at a mean of 9.2 days. At the final mean follow-up of 425 days, only 4 players had reached preinjury function in all measurements; 12 players were able to return in 2 of the 4 metrics; and only 8 players reached their preinjury ability to maintain high velocity. For those who did not achieve this metric, there was a significant difference between pre- and postinjury values (722 vs 442 m; P = .016). A total of 14 players were able to regain their IMA. Players who returned to prior velocity or acceleration metrics did so at a mean of 163 days across all metrics. Conclusion: While players may be able to return to play after hamstring strain, many players do not reach preinjury levels of acceleration or velocity, even after 13.5 months. Further studies are needed to confirm these findings, assess clinical relevance on imaging performance, and improve hamstring injury prevention and rehabilitation.

Background: The prevalence of meniscal tears in patients with anterior cruciate ligament (ACL) injury increases with extended time between injury and ACL reconstruction. Purpose/Hypothesis: The purpose of this study was to determine if there is a relationship between time from magnetic resonance imaging (MRI) to ACL reconstruction and the predictive value of MRI to diagnose meniscal tears in the young active population. It was hypothesized that increased time between MRI and ACL reconstruction would lead to a decrease in the negative predictive value of MRI in diagnosing meniscal tears, as more injuries may accrue over time in the ACL-deficient knee. Study Design: Case series; Level of evidence, 4. Methods: Included were patients aged 13 to 25 years at the authors’ institution who underwent primary ACL reconstruction from January 2017 to June 2020. Time from MRI to surgery as well as descriptions of medial and lateral meniscal tears on both MRI and operative reports were documented. Time from MRI to surgery was divided into 4 intervals: 0 to 6 weeks, >6 weeks to 3 months, >3 to 6 months, and beyond 6 months. Multivariable analysis was used to determine the positive and negative predictive values of MRI in diagnosing a meniscal tear as compared with arthroscopic findings. Results: A total of 432 patients were included with a mean age of 17.9 ± 3.4 years. The mean time from MRI to surgery was 70.5 ± 98 days. There was a significant decrease in the negative predictive value of MRI to identify a medial meniscal tear in patients who underwent ACL reconstruction >6 months after imaging (odds ratio, 0.16 [95% CI, 0.05-0.53]; P = .003). This same relationship was not shown for lateral meniscal tears, nor was any other predictor significant. Conclusion: The utility of MRI to rule out a medial meniscal tear significantly diminished in the young athletic population when >6 months passed between MRI and ACL reconstruction. These data suggest these tears occur between the time of the MRI and surgery and that the medial meniscus is more susceptible than the lateral meniscus to new injury once the ACL has torn.

We remain honored and humbled to have been 2023 Arthroscopy Association of North America (AANA) Traveling Fellows. To borrow a previous Traveling Fellow's tweet: "Every fellowship class thinks their year was the best… but ours was." Our godfather and past president of AANA, Nicholas Sgaglione, M.D., appropriately from New York, was the quintessential godfather. Spanning the U.S. coast to coast and Canada, the fellowship class comprised of Albert Gee, M.D., Associate Professor and Chief of Sports Medicine at University of Washington in Seattle and Team Physician University of Washington; Catherine Hui, M.D., Associate Clinical Professor at University of Alberta and Knee Team lead at Glen Sather Sports Medicine Clinic; Theodore Shybut, M.D., faculty at Southern California Orthopedic Institute and Team Orthopedic Surgeon for College of the Canyons; and Peter S. Vezeridis, M.D., from Boston, attending surgeon at Excel Orthopaedic Specialists in Woburn, MA. Communications with AANA Traveling Fellows from past years were unanimous—it would be a professional high point and the adventure of a lifetime. On our prefellowship virtual meeting, Dr. Sgaglione made his first godfatherly decree—"nothing beats having fun" while learning and teaching. What better way to kick off a traveling fellowship than by going international. The team assembled in our hotel Monday evening, where previous AANA Traveling Fellow Dr. Diego Perez-Salazar's chariot (aka minivan) awaited. Dr. Sgaglione impressed on us that AANA was like family to him, and we experienced that immediately as we were warmly welcomed into our host's home, where we met his family and colleagues. Amicable conversation in his yard was fueled by our excitement at the adventures before us, Dr. Perez-Salazar's own fellowship experiences, and margaritas. A delicious meal of traditional Mexican dishes, bested only by the company at the table followed, where we learned that Dr. Pedro Iturbide-Siles's surgical mantra borrowed from the Mandalorian: "This is the way" (Fig 1). As we departed, our generous hosts surprised us with personalized fleece pullovers commemorating our AANA visit to ABC, with Dr. Sgaglione's fleece proclaiming the godfather to be a "goodfather." Tuesday morning, we were up early to catch a shuttle to ABC Medical Center (Fig 2). We had breakfast with chair Dr. Sergio Abush and multiple orthopaedic staff surgeons, then embarked for the operating room, where Dr. Iturbide-Siles and Dr. Perez-Salazar demonstrated techniques for anterior cruciate ligament (ACL) reconstruction with both quadriceps autograft and allograft, and complex medial meniscus repair. In addition, Dr. Pedro Palaez performed an arthroscopic suprapectoral biceps tenodesis. As we observed, we traded notes on our surgical preferences while the godfather shared his sage advice on the cases at hand. We quickly learned that in addition to his surgical expertise, our godfather was a movie buff: "Leave the gun, take the cannolis!" An early afternoon lunch was quickly followed with our first formal academic session of the trip (Fig 3). Dr. Perez-Salazar warmly welcomed us, and we gave knee and shoulder talks. Dr. Hui led off with Multicenter ACL Revision Study and ACL reconstruction evaluation followed by a technique presentation for meniscus root repair in conjunction with ACL reconstruction. Dr. Shybut presented ACL repair, "Back to the Future" (continuing the Hollywood theme), then Dr. Gee presented on ACL reconstruction and lateral extra-articular tenodesis followed by a talk on the University of Washington multiligament knee injury experience. Dr. Shybut presented a talk on augmentation of rotator cuff repairs, then Dr. Vezeridis hit cleanup presenting on lower trapezius transfer for irreparable rotator cuff tears followed by an update on the Latarjet procedure. Our hosts presented 2 shoulder cases: an arthroscopic bony Bankart repair and arthroscopic exploration and release of the brachial plexus. The talks were so well received and subsequent discussions so engaging that we ran well behind schedule and had to do a quick turnaround at the hotel before heading off for a delicious dinner at Carmela y Sal, where we tried the local delicacy, lechon. In addition, proving that AANA is a family-oriented organization and that he is worthy of both titles "goodfather" and "godfather," Dr. Sgaglione's daughter Caroline, who was visiting friends in Mexico City, joined us for dinner. Wednesday morning, Dr. Perez-Salazar kindly offered to take us running. Dr. Shybut and Dr. Vezeridis accompanied him to the Parque Mexicana, a beautiful oasis with rolling hills and the ubiquitous #CDMX photo spots nestled into a population 23 million metropolis. We were quickly reminded that Mexico City is at 7,349 feet above sea level. Three lung-burning laps of the park down, we grabbed coffee, cleaned up, and the team including Caroline caught a shuttle into the downtown city center. Our guide art teacher, Maggie Loya, pointed out national government buildings and the Aztec ruins on which the city was built before we toured St. Mary's Cathedral. Exiting St. Mary's, we viewed more Aztec ruins, then walked through the city to the Palacio de Bellas Artes. We took our time here marveling at the juxtaposition of elegant art deco architecture of the museum itself against stunning large-scale murals by the likes of Diego Rivera, Siqueiros, and Orozco (Fig 4). Our bus took us to the Roma neighborhood for lunch at Casa Virginia. Maggie bid us farewell, and we tucked into a delicious meal including mussels and Ibérico ham accompanied with refreshing libations. We continued to trade thoughts on the previous day's talks and surgical cases while also trying to absorb as much of the Mexico City experience as we could. Dr. Perez-Salazar, truly a super-host, met us to ensure our day was successful, then we were off to the National Museum of Anthropology. Once again, the architecture alone was worth the price of admission. Inside we were treated to an amazing collection of Aztec relics, including the Sun Stone (Aztec Calendar) as well as a model of Tenochtitlan, the former Aztec capital. Feeling inspired by the local culture and our visit to Chapultapec (which translates roughly to "hill of the grasshopper") Park, Dr. Hui and Caroline Sgaglione and Dr. Shybut sampled dried crickets, which were definitely best with hot sauce. We made our way to the Polanco neighborhood, where our hosts met us at Lampuga for a festive final dinner discussing life balance, career mentorship, and the importance of being a member in AANA. We enjoyed great seafood and terrific company and shared farewell toasts, thanking our hosts many times over as we reflected on this special time we spent together in Mexico City. Inspired by our run the day before, Dr. Hui joined Dr. Shybut and Dr. Vezeridis Thursday for one more morning run at the Parque Mexicana before we all packed up for transport to the airport. Unfortunately, our departure was delayed, each time increment resulting in another souvenir purchase by Dr. Gee from the airport gift shops. Once on board, we were subject to pilot work-hour restrictions, so our plane was diverted to Dallas. The Godfather and co-fellows joked that Dr. Shybut missed Texas and so had arranged for a quick visit. We made up for the dinner we missed in Scottsdale as best we could. A quick bite with a round of beers, and finally a nap-laden flight led to a midnight landing in Phoenix, our second stop on the tour. Mexico City was marked by extraordinary organization and thoughtful planning, warm genuine hospitality, shared world-class innovative and state-of-the art clinical surgery and case presentations, as well as thoughtful discussions on academics, collegial experiences, and life balance. The privilege and unique honor and opportunity to meet with and share and learn from our expert Mexican colleagues was memorable. They all demonstrated team work at its best, and we were able to better understand their experiences and expertise in an international setting which was invaluable, eye-opening, and rewarding. We forged relationships and bonds that will last forever. After an unexpected detour through Dallas, we arrived in Phoenix, Arizona, to be greeted by Dr. Kostas Economopoulos, one of the 2021 AANA Traveling Fellows. He most graciously picked us all up with a smile on his face at 12:30 AM after waiting 8 hours for our delayed flight. We decided as a group to travel "light." Our Tetris skills were on full display as we piled our luggage into Mrs. Economopoulos' car and headed for some much-needed rest at the Hilton near the Mayo Clinic Campus. The next morning, AANA incoming President Dr. John Tokish and his fellow, Dr. Justin Makovicka, picked us up bright and early at the hotel, and we started our day with some breakfast burritos followed by an academic session in the laboratory. We watched Dr. Tokish masterfully perform an arthroscopic biceps tenodesis followed by his innovative "biceps smash" procedure with autogenous biceps patch for rotator cuff repair augmentation (Fig 5). We learned how he developed the technique, including how he tested the tendon remnant and found >85% tenocyte viability. He also demonstrated the new instrumentation for the technique along with some pearls for the augmentation. After the biceps smash, Drs. Tokish and Makovicka demonstrated how to perform an arthroscopic distal tibial allograft for shoulder instability. We were given the opportunity to discuss his idea development and were awed by his innovation and expertise. We grabbed some sandwiches at the laboratory and left to make our tee time at Wildfire Golf Club. Our afternoon session started with all our golf swings on display at the driving range, and eventually we established the format for the afternoon. Dr. Sgaglione would lead a team consisting of Dr. Shybut, Dr. Vezeridis, and Dr. Makovicka. Dr. Tokish would lead a team consisting of Dr. Hui and Dr. Gee (Fig 6). This team would have the opportunity to hit one extra ball per hole to make up for having one less player. The rules were set, and it was decided that the losing team would have to ride the mechanical bull later that evening. Dr. Makovicka showed off his long drives but that was not enough to defeat Dr. Tokish's team. We left the stunning views of North Phoenix from Wildfire Golf Club and headed off to freshen up for the evening festivities. Saturday morning in Arizona started with a drive to the hanger in Glendale, Arizona, where we met our pilots for the day's first adventure. Dr. Tokish had arranged for us to fly through the Grand Canyon in 2 Cessna 172 airplanes (Fig 7). We all had visions of Tom Cruise flying through the canyon in Top Gun Maverick. Dr. Hui and Dr. Gee watched videos on the internet on how to add the Top Gun theme song to the AANA Instagram post they made, and the Godfather was fueling up on Vitamin V while we waited for the pilots to prepare for our flight. We then loaded up with Drs. Gee, Shybut, and Economopoulos in one plane with Pilot Christine and Drs. Hui, Vezeridis, and Sgaglione in the other with Pilot Chris. We studied the flight plan, which first took us north towards the Grand Canyon—passing Sedona, Mount Humphrey, and Flagstaff (Fig 8). The weather was absolutely perfect, and we had views of the world's wonder that we could only imagine. We then looped around and headed south, landing in Sedona, our next stop. It was a spectacular flight that left our Godfather at a loss for words (Fig 9).Fig 8Cessna 172 flight plan for Saturday, April 29, 2023, flight over the Grand Canyon.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig 9Stunning views from above the red rock and evergreens of Sedona as we prepare for landing.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Dr. Makovicka picked us up and drove us to the town of Sedona for lunch. After lunch, we had some time to explore the cute and charming town of Sedona surrounded by picturesque red-rock scenery before arriving at Pink Jeep Tours (Fig 10), where we met Dr. Tokish, who drove from Phoenix to meet us. We all packed into one Pink Jeep along with our driver, Ray. Ray was an interesting fellow who was an excellent driver. He took us off-roading on the jeep on some harrowing roads and up to several breathtaking viewpoints of Sedona. He was a wealth of knowledge regarding the history of Sedona, which was named after Sedona Arabella Miller Schnebly, who was the wife of Theodore Carlton Schnebly, the city's first postmaster, to teaching us about the vortices in Sedona. We learned that a vortex is swirling center of energy that is conducive to healing, meditation, and self-exploration leading people to feel inspired, recharged, and uplifted after a visit (Fig 11). We arrived safely back to Sedona and drove back to our hotel in Scottsdale, where we had a pizza dinner at Pitch next to the hotel. Surprisingly, they had a great bourbon menu and we had an impromptu bourbon tasting led by Dr. Tokish and Dr. Shybut, who is a connoisseur as well. Our night finished with a bourbon nightcap and some farewell pictures with the team.Fig 11At one of the spectacular viewpoints overlooking Sedona. Pictured from left to right: Dr. Justin Makovicka, Dr. Peter Vezeridis, Dr. Albert Gee, The Godfather (Dr. Nicholas Sgaglione), Dr. Catherine Hui, Dr. Kostas Economopoulos, Dr. J.T. Tokish, and Dr. Theo Shybut.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Sunday morning, we were driven to the airport by the ever-so-gracious Dr. Economopoulos and we departed to New Orleans with a quick stopover in Houston, where we had lunch at Little Purse Dumpling House. Dr. J.T. Tokish welcomed us with his incredibly legendary down-to-earth hospitality and energic spirit. He shared his enormous clinical and educational wealth. Dr. Tokish and his team make everything look easy in a fun and comfortable manner, teaching us some of his innovative approaches to complex shoulder problems. As the timing of our visit to Phoenix was over a weekend, we did not have a full academic schedule, but the ability to have mentorship discussions and shared philosophic insights about taking care of patients and many life lessons with an AANA legend over a whiskey was and will be incredibly memorable. We shared pearls, stories, and many laughs. Although none of us experienced the "vortex" that Ray described, we all felt inspired, recharged, and uplifted about becoming leaders in orthopaedic surgery after our visit in Phoenix. We arrived in New Orleans on a beautiful Sunday afternoon, greeted by live jazz in the airport lobby and a friendly driver. After checking in to the Hyatt Centric Hotel in the French Quarter, the Fellows enjoyed a run along the Mississippi River. Our evening consisted of exploring the very colorful French quarter. First stop was Lafitte's Blacksmith Shop Bar. This was followed by Pat O'Brien's for their signature "Hurricanes" and Preservation Hall to listen to some jazz. Dinner at Oceana Grill consisted of many delicious New Orleans specialties. An early Monday morning pickup brought us to Tulane University's Lakeside Hospital, arranged by Department Coordinator extraordinaire Maryann Walker. We were treated to a stimulating operating room day with American Academy of Orthopaedic Surgeons and AANA Past President and master surgeon Buddy Savoie (Fig 12). We were also welcomed by his wonderful wife and operating room coordinator, Amy Savoie. Dr. Savoie's cases included a double-row rotator cuff repair with suprascapular nerve decompression and acromioclavicular joint resection, a massive rotator cuff repair with bioinductive scaffold augmentation and balloon spacer, and an anatomic total shoulder arthroplasty. In addition to lively discussions about his surgical techniques and approach, Dr. Savoie taught us about nutritional adjuncts that he employs to improve rotator cuff healing. After a quick lunch at Lakeside Hospital, we were treated to an afternoon swamp and alligator tour on airboats. Our captain, Miles, an eighth-generation colorful Cajun bayou expert, led us on a lively tour along with his 1-year-old pet alligator Louie (Fig 13). We saw beautiful wildlife, including purple gallinule birds and many alligators up close. Who knew alligators love snacking on marshmallows! On Monday night, Dr. Savoie and the sports service arranged for us to dine in a private room at the famous and classic New Orleans restaurant Antoine's. We were hosted by Dr. Savoie and his wife Amy, Dr. Michael O'Brien, Dr. Wendell Heard and his wife Asha Heard, M.D., chief resident Wendell (Cody) Cole, M.D., and sports fellow Reaves Crabtree, M.D. The meal's grand finale was a special AANA Baked Alaska, an exquisite dessert originating from Antoine's (Fig 14).Fig 13(A) In the afternoon, the team attends on a wonderful airboat tour of the bayous where they spot multiple alligators. Front row from left: Peter Vezeridis, M.D., Reaves Crabtree, M.D., and Catherine Hui, M.D. Second row from left: Nicholas Sgaglione, M.D., and Theodore Shybut, M.D. Third row from left: Albert Gee, M.D., and Wendell (Cody) Cole, M.D. (B) The Traveling Fellows were able to hold baby alligator Louie during their airboat tour of the bayous.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig 14(A) In the evening, Felix H. Savoie III, M.D., former AANA Traveling Fellow Michael O'Brien, M.D., and their team treated the Traveling Fellows and Godfather to a spectacular meal at Antoine's Restaurant. From Left: Albert Gee, M.D., Theodore Shybut, M.D., Michael O'Brien, M.D., Catherine Hui, M.D., Peter Vezeridis, M.D., Wendell Heard, M.D., Nicholas Sgaglione, M.D., Asha Heard, M.D., Felix Savoie III, M.D., Amy Savoie, M.D., Wendell (Cody) Heard, M.D., and Reaves Crabtree, M.D. (B) The meal's grand finale was a special AANA Baked Alaska. From left: Peter Vezeridis, M.D., Albert Gee, M.D., Nicholas Sgaglione, M.D., Theodore Shybut, M.D., and Catherine Hui, M.D.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Tuesday brought another enriching morning of surgery at Tulane's Lakeside Hospital. Dr. Michael O'Brien, who is an AANA Traveling Fellowship alumnus, had many interesting cases, including a revision double-row rotator cuff repair augmented with dermal allograft, an elbow dislocation treated with medial ulnar collateral ligament repair with suture augmentation and lateral stabilization, and a reverse shoulder arthroplasty using intraoperative navigation (Fig 15). The Fellows and Godfather thoroughly enjoyed the great demonstration of complex cases and innovative techniques. This was followed by a delicious lunch at Luke's Restaurant with amazing Cajun fare. In the afternoon, we experienced a fascinating tour of Blaine Kern's Mardi Gras World (Fig 16). This exhibit is housed in a huge warehouse adjacent to the Mississippi River. We learned about the Mardi Gras traditions of New Orleans including the parades, krewes, and design and construction of the colorful and unique floats. In the evening, the Fellows each presented a lecture at Tulane's Department of Orthopaedics Grand Rounds, with a large group of faculty, fellows, residents, and medical students attending. Lively discussion followed each lecture. Following Grand Rounds, we stopped at the Bourbon House for old fashioneds and cigars. It was then on to dinner at the national historic landmark Napoleon House to enjoy their famous muffuletta sandwiches. Finally, we wandered through the French Quarter to Tropical Isle for their notorious hand grenades, per Dr. O'Brien's recommendation. The Fellows found themselves holding a 16-foot reticulated python for a unique experience and photo opportunity (Fig 17).Fig 16The Traveling Fellows experience a fascinating tour of Mardi Gras World, where they learned all about the float creation and Mardi Gras traditions of New Orleans. From left: Albert Gee, M.D., Catherine Hui, M.D., Nicholas Sgaglione, M.D., Theodore Shybut, M.D., and Peter Vezeridis, M.D.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig 17The Traveling Fellows hold a 16-foot reticulated python on Bourbon Street. From left: Catherine Hui, M.D., Theodore Shybut, M.D., Nicholas Sgaglione, M.D., Albert Gee, M.D., and Peter Vezeridis, M.D.View Large Image Figure ViewerDownload Hi-res image Download (PPT) On Wednesday morning, we were fortunate to have another amazing operative experience with Dr. Buddy Savoie. Fascinating cases included arthroscopic debridement of calcific tendinopathy and rotator cuff repair, elbow arthroscopy and distal ulnar collateral ligament repair in a javelin thrower, revision anterior labral repair with remplissage and interval closure, and revision rotator cuff repair with bioinductive scaffold, balloon spacer, and arthroscopic suprapectoral biceps tenodesis. Dr. Savoie treated us to another masterful demonstration of his expertise in treating complex shoulder and elbow pathologies. In the afternoon, we toured the Tulane Institute of Sports Medicine at Tulane's Yulman Stadium (Fig 18). Head physical therapist Andre Labbe was our gracious and engaging host. After lunch at the student athletes center, we visited the football stadium of the Tulane Green Wave, winners of the epic 2023 Cotton Bowl. Our tour also included the baseball stadium, training center, and Tulane Institute of Sports Medicine Clinic. An eye-opening, enjoyable, and interesting visit, we consistently saw pride, dedication, commitment, and excellence throughout the Tulane Department of Orthopaedics. The Tulane University leg of our journey completed an extraordinary trip through 2 countries and 3 department sites, encompassing strong academic and lively social experiences. Dr. Buddy Savoie and Dr. Mike O'Brien were extremely excited, welcoming, and invested hosts. Their commitment to the AANA Traveling Fellowship rewarded the Traveling Fellows and Godfather with a rich and balanced experience. We were treated to a vibrant academic program, highlighting their dedicated Tulane Department, and a one-of-a-kind immersive and memorable New Orleans visit. We are so grateful that we could see the city and its people at their best—vibrant, colorful, and very much alive. The end of the traveling fellowship dovetailed nicely with the 2023 AANA Annual Meeting, which was held in New Orleans. It was a nice change of pace, as we did not have to travel again, just move hotels. On Wednesday, the night before the official start of the meeting, we all attended the President's reception and were privileged to spend some time sharing a drink and some hors d'oeuvres with many emerging and established leaders of AANA, including our President, Dr. Jim Stone, and the Program Chair for the meeting, Dr. Brian Waterman. As the meeting was scheduled to start in full the next day, this evening represented the last official day of our tour as 2023 Fellows. To celebrate, the Godfather arranged for us to have one last dedicated dinner, which we enjoyed at a historical NOLA restaurant, The Court of the Two Sisters. The Godfather's lovely wife Ela had just arrived in town from New York City to join him for the meeting, and she honored us with her presence at dinner. It was nice to see Dr. Sgaglione sharing a small part of this great adventure with another one of his family. Seeing him with his loved ones made us all realize how wonderful a father, husband, and just all-around great human being he is and how fortunate the Traveling Fellows were to be able to call him our Godfather. We will all remember how his warm and friendly personality put everyone immediately at ease, which was invaluable as we traveled and met new colleagues. He was always calm and collected even under duress (see aforementioned Grand Canyon airplane tour). For such a busy man with an active clinical practice and the responsibilities of Chairman of a large department, never once during our time traveling did we see him distracted or stressed by his work back at home. He was always present in the moment for all of our undertakings, enjoying the experience and being grateful for the time we shared together. In this way, he was a shining example for the fellows, and we could reflect upon our time with the Godfather and strive to become more like him in our own lives balancing busy work and family schedules. The meeting started in full on Thursday morning, and we all started our day early with educational sessions covering various topics from shoulder to ankle. We each had some separate interests that drove us to different sessions. We reconvened in the afternoon on Thursday for the Award Presentations where we were formally recognized. The Godfather gave a summary of our adventures and then introduced us to the stage for our awards (Fig 19). This was followed by the Welcome Reception later that evening where we got to reunite with a number of our hosts from the various sites who had traveled to New Orleans for the meeting, including Drs. Perez Salazar, Iturbide-Siles, Tokish, Economopoulos, Savoie, and O'Brien. Friday was another busy meeting day for all. In another reunion of sorts, Drs. Hui and Dr. Perez Salazar Marina (host from Mexico City), served as moderators for the session on meniscus preservation and was joined in the same session by our Godfather (Fig 20), who moderated the case panel. The Godfather had another session to rush off to afterwards, as he was speaking on biologic augmentation, while Dr. Hui gave her presentation on ACL and meniscus root repair during the AANA/Ruth Jackson Orthopaedic Society Forum. Friday evening was the Don Johnson Traveling Fellowship Alumni Reception. It was a great gathering of all the alumni of the Fellowship from years past (Fig 21). Seeing and meeting the many fellows who had gone before us and their Godfathers, we realized what an amazing family of surgeons we had just been welcomed into and felt very honored. Saturday was the final day of the meeting, and the day started with a fun and informative session called "Battle Royal! Debate your Mentor." This session paired off 2 AANA faculty members who were mentor/mentee to debate a controversial topic, and the audience got to vote on who won the "battle." Dr. Gee presented in the afternoon session on the treatment of degenerative meniscus tears in the aging athlete. In what seemed to us like the blink of an eye, the educational part of the AANA meeting had come to a close. With the educational session of the meeting over, we were fast approaching the end of our time together as Fellows. The last event on our agenda before the dreaded end of our incredible trip, was the AANA President's Reception, which was to be held that evening at the National World War II Museum. However, there was a few hours of down time between the end of the meeting and the reception, so we set off into the French Quarter again for one last tour of some of the historic spots that we had not been able to visit yet. We made our way to Jackson Square and Café du Monde, where we drank chicory coffee and had our fill of their world-famous beignets. We explored the specialty shops in the Quarter to find genuine Creole spices and seasoning that Dr. Hui wanted to take back to Canada for some Cajun cooking. Lastly, we visited the Carousel Bar, which was inside the Hotel Monteleone and is famous for having a rotating carousel for a bar (Fig 22). The carousel has 25 seats and rotates once every 15 minutes. Another reason we wanted to visit the Carousel Bar was to try their famous cocktail, the Vieux Carré. This cocktail had been invented there and is made from rye whisky, cognac, sweet vermouth, Benedictine, and Peychaud's bitters (for those who want to try and mix it at home!). The name Vieux Carré is French for "old square" in reference to the French Quarter. We ordered a round of them and then fortuitously, despite it being a busy Saturday afternoon, we were able to find seats together at this famed rotating bar. It also happened to be Kentucky Derby day, and by chance we were able to watch the famous race on TV while going around the carousel and enjoying our drinks. (The winner was a thoroughbred named Mage.) It was another unforgettable Fellows bonding experience, staying true to the mantra of our trip that "Nothing beats having fun!" We made it back to our hotel just in time to get ready for the President's Reception that evening. A short shuttle bus ride, and we arrived at the World War II Museum. The Museum campus is vast and expansive and filled with exhibits that provide an amazingly comprehensive accounting of World War II. The reception was held in the U.S. Freedom Pavilion, which housed an incredible display of fully restored planes flown during the war. It was a very moving place to have the closing event of this year's AANA meeting. We explored the various exhibits and went up onto a catwalk high in the air to get close-up views of the various planes suspended from the ceiling (Fig 23). We ate and drank and mingled and danced away the evening with all the AANA members still in town (a live DJ was there to keep the party live and the dance-floor full). The President's Reception this year was open to all AANA members that attended the meeting, and it was yet another example of how inclusive and generous AANA is as an organization. Once again, we were honored to be a part of the AANA family and felt tremendous gratitude for the Fellowship experience that AANA afforded us. Alas, the evening came to a close. We made our way back to the hotel and said our final farewells to one another and to our Godfather. We all got a bit choked up with emotion, and it was hard to say goodbye. We had shared a life-changing experience together, and it was sad to have to part ways. Thankfully, our Godfather left us with a comforting sentiment that this was not "goodbye" but rather "until next time" and that this was not the end but just the beginning of our friendship and fellowship. We all knew without saying that our connection as 2023 Traveling Fellows would be a bond we all would cherish for the rest of our lives. Download .pdf (.16 MB) Help with pdf files ICMJE author disclosure forms

Objectives: For young athletes with anterior cruciate ligament (ACL) injury, ACL reconstruction is usually recommended to restore stability to the knee. Previous studies have shown that increased time from ACL injury to ACL reconstruction can lead to the accrual of new injuries over time, specifically medial meniscus tears. In addition, increased time from magnetic resonance imaging (MRI) to ACL reconstruction in these patients decreases the predictive value of MRI imaging as a diagnostic tool for concomitant injuries. However, risk factors for delay in care for ACL injuries remain undetermined. To our knowledge, no prior study has examined the impact of social determinants of health on the timing of MRI and ACL reconstruction after ACL injury in young athletic patients. The goal of this study is to investigate what social determinants of health may impact timing of care in young athletes with ACL injury. Methods: We retrospectively reviewed the electronic medical records of all patients aged 13-25 years at a single orthopaedic surgery department who underwent isolated primary ACL reconstruction from January 2017 to June 2020. We excluded patients who were not self-reported athletes or charts without MRI, operative report, or date of initial injury. We documented the time from injury to MRI, MRI to surgery, and injury to surgery. Demographics were recorded including age, gender, body mass index (BMI), race/ethnicity, and insurance type (public versus private). Multivariable analysis was used to determine if any demographic factor had a significant association with increased time to MRI or surgery after initial injury. Results: A total of 432 patients met inclusion and exclusion criteria (mean age 17.9, 46% male). On multivariable analysis, there were significant associations between BMI and timing of care while holding all other predictors constant. There were 249 patients with normal BMI, 106 overweight (BMI 25 – 29.9), 60 obese (BMI >= 30), and 17 underweight (BMI < 18.5). Patients with obese BMI had an injury to MRI time that was on average 77.6 (95% CI: 20.7–193.4; p = 0.015) days longer than those with normal BMI, and an increased time from injury to surgery that was on average 107.2 [95% CI 11.3–203.1; p < 0.029] days longer than those with normal BMI. Patients with overweight BMI had an MRI to surgery time that was on average 34.3 [95% CI: 9.2–59.4; p < 0.007] days longer than those with normal BMI and an injury to surgery time that was on average 74.6 [95% CI: 2.3–147; p < 0.043] days longer than those with a normal BMI. No other demographic factors had a statistically significant association with the timing of care, although public insurance and minority race/ethnicity trended toward delays in care. Conclusions: This multivariable analysis of over 400 patients from a single institution demonstrates that athletes with ACL injuries that have higher BMI experience increased time to MRI and surgical care compared to patients with normal BMI when controlling for other variables. While the cause of the delay for this group may be multifactorial, understanding this disparity in health care and using it to uncover our hidden biases may help us provide better patient care to all.

Overuse injuries of the rotator cuff, particularly of the supraspinatus tendon (SST), are highly prevalent and debilitating in work, sport, and daily activities. Despite the clinical significance of these injuries, there remains a large degree of uncertainty regarding the pathophysiology of injury, optimal methods of nonoperative and operative repair, and how to adequately assess tendon injury and healing. The tendon response to fatigue damage resulting from overuse is different from that of acute rupture and results in either an adaptive (healing) or a maladaptive (degenerative) response. Factors associated with the degenerative response include increasing age, smoking, hypercholesterolemia, biological sex (variable by tendon), diabetes mellitus, and excessive load post fatigue damage. After injury, the average healing rate of tendon is approximately 1% per day and may be significantly influenced by biologic sex (females have lower collagen synthesis rates) and excessive load after damage. Although magnetic resonance imaging (MRI) is considered the gold standard in assessing acute tears as well as tendinopathic change in the SST, ultrasonography has proven to be a valuable tool to measure tendinopathic change in real time. Ultrasonography can determine multiple mechanical and structural parameters of the SST that are altered in fatigue loading. Thus, ultrasonography may be utilized to understand how these parameters change in response to SST overuse, and may aid in determining the activity level that places the SST at greater risk of rupture.

Objective To compare the diagnostic performance of direct magnetic resonance arthrography (MRA) for labral lesions during conventional, abduction and external rotation (ABER), conventional plus abduction, and external rotation (ABER) positioning by using a systematic review and meta-analysis. Materials and methods A comprehensive literature search was performed on the two main concepts of magnetic resonance arthrography: extremity position and labral lesions. Inclusion criteria consisted of original studies that assessed the diagnostic accuracy of MR arthrography in ABER and conventional position alone or combined for the diagnosis of labral lesions by using surgical findings as the reference standard. Meta-analyses were performed that compared MR arthrography during conventional positioning, ABER, and conventional plus ABER positioning. Results Nine studies met the inclusion and exclusion criteria. A total of 733, 504, and 313 lesions assessed by conventional MRA, ABER MRA, and conventional plus ABER MRA, respectively, were included in our analysis. Pooled sensitivities of MRA in conventional, ABER, and conventional plus ABER position for labral tear diagnosis were 81.5%, 81.6%, and 95.7%, respectively. Pooled specificities of MRA in conventional, ABER, and conventional plus ABER position for labral tear diagnosis were 88.8%, 85.6%, and 94.5%, respectively. Summary receiver operator characteristic (ROC) curve demonstrated improved accuracy of conventional plus ABER MRA compared with conventional MRA or ABER MRA with the area under the curve (AUC) of 0.99, 0.90, and 0.88, respectively. Conclusion Conventional plus ABER MRA showed increased diagnostic accuracy compared to both ABER MRA and conventional MRA alone in the diagnosis of labral lesions.

Background: A delay in anterior cruciate ligament reconstruction (ACLR) is associated with an increase in the prevalence in medial meniscus tears identified at the time of surgery. However, the specific effect of time on the predictive value of magnetic resonance imaging (MRI) for detecting meniscus injury in the young athletic population with ACL tears is unclear. Purpose: To investigate the effect of time from MRI to ACLR on the predictive value of MRI to detect meniscus tears in adolescent and young adult athletes. Methods: A retrospective review was performed of patients aged 13-25 years who underwent primary ACLR at an academic institution from January 2017 to June 2020. Multi-ligament injuries were excluded. Primary data recorded included time from MRI to surgery and descriptions of medial and lateral meniscus tears on both MRI and operative reports. Time from MRI to surgery was divided into four intervals: 0 to 6 weeks, 6 weeks to 3 months, 3 months to 6 months, and beyond 6 months. Multivariable analysis was used to determine the positive (PPV) and negative predictive value (NPV) of MRI in detecting meniscus tears as compared to arthroscopic findings at each of the 4 time intervals. Results: 432 patients (54% female) were included with a mean age of 18 ± 3.4 years. The mean time from injury to MRI was 78 ± 187 days; the mean time from MRI to surgery was 71 ± 98 days. 252 patients had pre-operative MRIs without meniscus tears; 33 (13.1%) of those had a medial meniscus tear identified at the time of surgery (Table 1). New medial meniscus tears (100% vertical tears) were identified in 7/18 (38.9%) patients with surgery 6 months from MRI. There was a statistically significant decrease in the NPV of MRI to identify medial meniscus tears in patients who underwent ACLR greater than 6 months after imaging (odds ratio 0.16 [0.05–0.53], P < 0.005). Age, gender, body mass index, mechanism of injury, primary sport, and ethnicity did not affect the predictive value of MRI. Sensitivity and specificity of MRI to predict a medial meniscus tear in the entire cohort was 79% and 80%, respectively. Conclusion: Surgeons should counsel patients preoperatively about increased possibility of undiagnosed medial meniscus tears being found at the time of ACLR if greater than 6 months have passed from MRI to surgery. Table 1. Breakdown of Medial Meniscus Tears by Time from MRI until Surgery

Purpose:To compare stiffness, strain, and load to failure of 4- versus 5-strand hamstring anterior cruciate ligament reconstruction human tendon allografts with femoral suspensory and tibial interference screw fixation.Methods:Allograft hamstring tendons were used to create 10 four-strand (4S) and 10 five-strand (5S) grafts. Grafts were fixed to a uniaxial electromechanical load system via a femoral cortical suspensory button and a bioabsorbable interference screw in bone analogue. Grafts were cycled from 100 Newtons (N) to 250 N for 1,000 repetitions at 0.5 hertz before load to failure testing. Cyclic displacement was defined as the difference in graft length from the first 20 to 30 cycles compared with the last 10 cycles. Trials were recorded on a high-definition camera to allow for digital image correlation analysis.Results:Cyclic displacement more than 1,000 cycles was significantly lower in the 4S compared with the 5S group (0.87 vs 1.11 mm, P = .037). Digital image correlation analysis confirmed that the fifth strand elongated more than the other 4 strands in the 5S constructs (6.1% vs 3.9%, P = .032). Load to failure was greater in the 4S compared with the 5S group but not statistically significant (762 vs 707 N, P = .35). Stiffness was similar between constructs (138.5 vs 138.3 N/mm, P = .96).Conclusions:Compared with cyclically loaded 4S hamstring grafts, the 5S grafts had significantly increased displacement over time in a model of femoral suspensory and tibial interference screw fixation.Clinical Relevance:Anterior cruciate ligament reconstruction with hamstring tendon autograft is a commonly performed surgery with excellent outcomes. It has been shown that graft diameter influences these outcomes. As surgeons use larger grafts, it is important to investigate how these constructs may affect the outcomes of surgery.

Background: In the setting of meniscus pathology, earlier treatment of meniscus tears may increase the likelihood of repair in young patients. Moreover, delayed anterior cruciate ligament reconstruction (ACLR) has been associated with an increased risk of meniscus injury. There is, however, limited data on the relationship between surgical delay and meniscus repairability in the setting of an ACLR in young patients. Purpose: The purpose of this study was to examine meniscus tear patterns and the likelihood of repair at the time of ACLR in young athletes, and specifically, to determine whether age and time from injury to surgery are correlated with tear patterns or meniscus repairability. Methods: Records were retrospectively reviewed on patients aged 13-25 years who underwent primary ACLR from January 2017 through December 2017. Patients with multi-ligament knee injuries were excluded. Demographic data were collected including age, sex, BMI, race/ethnicity, insurance status, primary sport, mechanism of injury, and time from injury to surgery. Operative reports were reviewed to document meniscus tear type/pattern and all concomitant pathology/procedures. Univariate and logistic regression analyses were used to determine factors associated with meniscus repair. Results: 89 eligible patients underwent ACLR during the study period. 59 (51% females) with mean age 19.3 ± 3.4 years had concomitant meniscus pathology and were included for analysis. The mean time to surgery was 5.2 ± 7.4 months. Combined medial and lateral meniscus tears accounted for 37% of tears, followed by lateral (32%) and medial (31%) tears. For tear type, medial and lateral tears were most commonly vertical (57.5%) and complex (34%), respectively. Surgical repair was performed in 67.5% of medial tears but only 34% of lateral tears. Univariate analyses demonstrated a statistically significant correlation between medial meniscus repair and time to surgery ( p=0.01) and age ( p=0.01), with repair less likely with a surgical delay >3 months and age >18 years. However, time to surgery was not significant after adjusting for age. There was a statistically significant difference in age between those with a surgical delay > 3 months (20.6 ± 3.4 vs.18.3 ± 3.0; p=0.01). Age and time to surgery did not affect the location or type of meniscus tear. There was no correlation between other demographic or surgical variables and time to surgery. Conclusion: In the setting of concomitant ACL and medial meniscus injury, age >18 years and surgical delay >3 months may decrease the likelihood of medial meniscus repair in young athletes.

Background: Delayed anterior cruciate ligament (ACL) reconstruction (ACLR) is associated with an increased risk of meniscal injury. Limited data are available regarding the relationship between surgical delay and meniscal repairability in the setting of ACLR in young patients. Purpose: To determine whether time from ACL injury to primary ACLR was associated with the incidence of medial and/or lateral meniscal repair in young athletes who underwent meniscal treatment at the time of ACLR. Study Design: Case-control study; Level of evidence, 3. Methods: Records were retrospectively reviewed for patients aged 13 to 25 years who underwent primary ACLR between January 2017 and June 2020 by surgeons from a single academic orthopaedic surgery department. Demographic data were collected, and operative reports were reviewed to document all concomitant pathologies and procedures. Univariable and multivariable logistic regression analyses were used to determine factors associated with meniscal repair, including time elapsed from ACL injury to surgery. Results: Concomitant meniscal tears were identified and treated in 243 of 427 patients; their mean age was 17.9 ± 3.3 years, and approximately half (47.7%) of patients were female. There were 144 (59.3%) medial tears treated and 164 (67.5%) lateral tears treated; 65 (26.7%) patients had both medial and lateral tears treated. Median time from ACL injury to ACLR was 2.4 months (interquartile range, 1.4-4.7 months). Adjusted univariate analysis showed a statistically significant correlation between medial meniscal repair and time to surgery, with a 7% decreased incidence of medial meniscal repair per month elapsed between injury and surgery (odds ratio, 0.93 per month; 95% CI, 0.89-0.98; P = .006). No similar relationship was found between lateral meniscal repair and time to surgery (odds ratio, 1.02; 95% CI, 0.99-1.06; P = .24). Conclusion: In the setting of concomitant ACL and meniscal injuries, surgical delay decreased the incidence of medial meniscal repair in young athletes by 7% per month from time of injury.

Repetitive stress injuries to the rotator cuff, and particularly the supraspinatus tendon (SST), are highly prevalent and debilitating. These injuries typically occur through the application of cyclic load below the threshold necessary to cause acute tears, leading to accumulation of incremental damage that exceeds the body's ability to heal, resulting in decreased mechanical strength and increased risk of frank rupture at lower loads. Consistent progression of fatigue damage across multiple model systems suggests a generalized tendon response to overuse. This finding may allow for interventions before gross injury of the SST occurs. Further research into the human SST response to fatigue loading is necessary to characterize the fatigue life of the tendon, which will help determine the frequency, duration, and magnitude of load spectra the SST may experience before injury. Future studies may allow in vivo SST strain analysis during specific activities, generation of a human SST stress-cycle curve, and characterization of damage and repair related to repetitive tasks.

INTRODUCTION:After anterior cruciate ligament reconstruction surgery, returning the knee to previous levels of strength and function is challenging, with the failure to do so associated with an increased risk of reinjury and long-term degenerative problems. Blood flow restriction (BFR) is gaining popularity as a rehabilitation technique; however, its effects on the mechanics of these exercises have not been fully explored. In this study, we aimed to determine the acute effects of BFR on the performance of a step-up exercise protocol and to assess the acceptability of the technique. METHODS:Twenty individuals (12 female/8 male; mean age, 30.6 yr) who had recently undergone anterior cruciate ligament reconstruction and 20 controls (11 female/9 male, mean age 28.0 yr) performed a step-up exercise protocol with and without BFR. Lower limb kinematics and kinetics were measured and compared between groups and conditions. Testing was completed in June 2019. RESULTS:Participants in both groups had increased external rotation of the tibia of 2° (P < 0.001) and reductions in knee flexion and rotation torques around the joint of around 50% (P < 0.001) when using BFR compared with nonrestricted step-up exercise. The intervention was found to increase the difficulty of the exercise and induce moderate levels of discomfort (P < 0.001). CONCLUSION:The present study provides cautious support for the use of BFR, showing that there are minimal changes in knee joint mechanics when performing the same exercise without BFR, and that the changes do not increase joint torques at the knee. From an acute biomechanical perspective, the intervention appears safe to use under qualified supervision; however, effects of repetitive use and long-term outcomes should be monitored.