Abstract:This cohort study aimed to identify whether time greater than 3 months between the onset of new symptoms of instability after primary anterior cruciate ligament (ACL) reconstruction (ACLR) and subsequent revision ACLR influences outcomes of revision surgery. We hypothesized greater than 3 months from onset of symptoms to revision ACLR is associated with increased intra-articular damage and poorer outcomes following revision ACLR. A retrospective chart review was conducted to identify patients who underwent revision ACLR at a large tertiary referral institution between 2008 and 2019. Demographic, surgical, and postsurgical data were collected. Patients who underwent revision ACLR within 3 months of documented graft symptomology were defined as the Early Revision group, and patients who underwent revision ACLR at or greater than 3 months after onset of graft symptomology were defined as the Late Revision group. Demographic data, intraoperative findings, subsequent graft failure, and patient-reported outcomes were compared between the groups. A total of 74 patients met inclusion criteria. Patients in the Late Revision group were more likely to have cartilage damage in the patella, trochlea, medial tibial plateau, lateral femoral condyle, and lateral tibial plateau. Patients in the Late Revision group were also more likely to have concomitant lateral meniscus tears. Medial meniscus tears identified at time of surgery in this group were also less likely to be deemed repairable. No significant differences were noted in postoperative Knee Injury and Osteoarthritis Outcome Scores, Marx Activity scores, or ACL graft retear risk based on the time from injury to surgery. Undergoing revision ACLR more than 3 months after graft tear is associated with more severe articular cartilage damage, more frequent lateral meniscus pathology, and a greater incidence of irreparable medial meniscus tears. No significant differences in patient-reported outcomes or revision graft failure risk were observed. Abstract:LEVEL OF EVIDENCE:  III.

BACKGROUND:Advancements in technology and techniques have shaped meniscus repair outcomes, but long term results remain unclear. This review aims to comprehensively evaluate studies with a mean follow-up of greater than 10 years following inside-out, outside-in, all-inside, open, or pull-out repair techniques. In addition, this article will review the impact of concomitant anterior cruciate ligament (ACL) reconstruction on long-term meniscus repair outcomes and compare osteoarthritis risk of patients treated partial meniscectomy compared with meniscus repair. We hypothesize there is increased evidence of osteoarthritis following partial meniscectomy compared to all types of meniscal repair. METHODS:PubMed and EMBASE databases were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inclusion criteria included full-text English language, human patients with at least one outcome reported after meniscus repair, and publication before June 22, 2021. Exclusion criteria included mean follow up of less than 10 years, published before the year 2000, or significant concomitant procedures within the knee during meniscus repair. RESULTS:Inside-out, all-inside, trans-tibial pull-out, and open repair techniques of meniscal tears demonstrate clinical success and good long-term outcomes. Data regarding the impact of concomitant anterior cruciate ligament reconstruction on meniscus repair outcomes are conflicting. The risk of osteoarthritis is reduced in meniscal repair when compared with partial meniscectomy. CONCLUSION:Outcomes of meniscus repair are favorable at 10 years post-operative regardless of technique. While the impact of concomitant ACL reconstruction on meniscus repair outcomes is unclear, meniscus repair is associated with decreased osteoarthritis risk compared to partial meniscectomy. Level of evidence IV; systematic review of level III-IV studies.

Abstract We evaluated the relationship between elevated body mass index (BMI) and mid- to long-term outcomes after surgical treatment of multiligamentous knee injury (MLKI). Records identified patients treated surgically for MLKI at a single institution. Inclusion criteria: minimum 2 years since surgery, complete demographics, surgical data, sustained injuries to two or more ligaments in one or both knees, and available for follow-up. Patients were contacted to complete patient-reported outcomes assessments and were classified according to mechanism of injury. Multivariate logistic regression analysis was used to predict the impact of BMI on outcome scores. A total of 77 patients (72.7% male) were included with a mean age at the time of injury of 29.4 ± 11.0 years and a mean BMI of 30.5 ± 9.4 kg/m 2 . The mean length of follow-up was 7.4 years. For each 10 kg/m 2 increase in BMI, there is a 0.9-point decrease in Tegner activity scale ( p  = 0.001), a 5-point decrease in Knee Injury and Osteoarthritis Outcome Score (KOOS)-pain ( p  = 0.007), a 5-point decrease in KOOS-ADL ( p  = 0.003), a 10-point decrease in KOOS-QOL ( p  = 0.002), and an 11-point decrease in KOOS-Sport ( p  = 0.002). There were no significant correlations with BMI and Pain Catastrophizing Scale or Patient Health Questionnaire scores. Increasing BMI has a negative linear relationship with mid- to long-term clinical outcomes including pain, ability to perform activities of daily living, quality of life, and ability to perform more demanding physical activity after MLKI. BMI does not appear to have a significant relationship with knee swelling and mechanical symptoms or patients' mental health.

The intercondylar notch of the knee is a relatively small area. However, numerous rare pathologies can arise in this region. A majority of the existing literature has focused on the cruciate ligament injuries, yet there are several other entities that can cause knee pain from within the intercondylar notch. This review focuses on identifying the various diagnostic and treatment options for rare benign and malignant lesions including ganglion cyst formation, mucoid degeneration, benign proliferative conditions, and intra-articular tumors. These entities are most often diagnosed with advanced imaging studies and treated arthroscopically. While rare, these pathologies are important to identify in patients with ongoing vague knee pain.

We sought to assess the current literature to present a comprehensive summary of the incidence, common pathogens, and risk factors for infection after anterior cruciate ligament (ACL) reconstruction. PubMed, CINAHL, EMBASE, and Scopus databases were searched for relevant studies reporting on infection after ACL reconstruction. Two reviewers independently screened the extracted studies for adherence to inclusion and exclusion criteria. Studies were selected if they reported on the incidence of infection, pathogens cultured from infected knees, or risk factors for infection after primary ACL reconstruction. Exclusion criteria consisted of studies with fewer than 100 patients or studies that included revision ACL reconstruction. Fifty studies met the inclusion and exclusion criteria, reporting on a total of 316,214 ACL reconstructions. Included studies evaluated between 123 and 104,255 patients. The overall incidence of infection was 0.60% (0.15-2.44%). The most common pathogens were Staphylococcus aureus, S. epidermidis, and coagulase-negative Staphylococci. Five studies reported that the use of hamstring autograft was a statistically significant risk factor for infection after ACL reconstruction, thus making hamstring autograft the most commonly reported risk factor. Other reported risk factors included male sex, use of immuno-suppressive medications or intraarticular steroid injections, prior knee surgery, and diabetes. Systematic review of the literature revealed that infection after ACL reconstruction remains an infrequent event with an incidence of 0.60% (0.15-2.44%). Furthermore, the most common pathogens are from the Staphylococcus genus of bacteria, comprising 84% of all culture-positive infections. Multiple risk factors have been reported for ACL reconstruction; however, statistical significance varied across studies. Together, these findings may help guide physicians in the prevention and treatment of infection after ACL reconstruction.

Background: Patellar dislocation is a common knee injury and up to 35% of those who dislocate the patella can develop recurrent patellar instability. In the setting of recurrent instability, medial patellofemoral ligament (MPFL) reconstruction is often performed to restore knee stability. There has been recent interest in patient and surgical factors that influence outcomes of MPFL reconstruction. Much of the previous work has focused on influences of anatomic measures; however, patients and injury characteristics may also impact surgical outcomes. Hypothesis: Patients who experience >2 patellar dislocations before MPFL reconstruction would demonstrate poorer patient-reported outcomes (PROs) compared with those with ≤2 previous dislocations. Study design: Cohort study; Level of evidence, 3. Methods: Records were reviewed to identify patients who underwent MPFL reconstruction at a single institution between 2008 and 2016. Patients who underwent concomitant tibial tubercle osteotomy or fixation of an osteochondral fracture were excluded. Patient demographics (age, sex, body mass index [BMI]), number of previous patellar dislocations, and patient anatomic measures (Caton-Deschamps index (CDI), tibial tubercle-trochlear groove (TT-TG) distance, and trochlear sulcus angle) were collected. PROs were assessed with Norwich Patellar Instability score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Marx activity score. Outcomes of patients with >2 patellar dislocations were compared with those with ≤2 dislocations using multiple linear regression analysis. Results: Medical record review revealed 160 patients who underwent isolated MPFL reconstruction (71 with ≥2 dislocations and 89 with >2 dislocations); 95 patients (59%) completed PROs at a median follow-up of 4.6 years postoperation (range, 1.0-12.6 years). Patients with ≥2 dislocations were younger (≥2 dislocations: 20.7 ± 7.3 years, >2 dislocations: 28.5 ± 10.0 years; P < .001), although there were no other differences in demographics or radiographic anatomic measures between groups. Adjusting for age, sex, BMI, CDI, TT-TG distance, and trochlear sulcus angle, patients with >2 dislocations had 13.7 points lower KOOS-Pain ( P = .003), 8.3 points lower KOOS-Activities of Daily Living ( P = .025), 18.2 points lower KOOS-Sports and Recreation ( P = .009), and 19.8 points lower KOOS-Knee-Related Quality of Life ( P = .008) subscale scores than patients with ≤2 dislocations. No significant differences in KOOS symptoms subscale, Norwich Patellar Instability, or Marx score were noted between groups. Conclusion: Patients with >2 patellar dislocations before MPFL reconstruction exhibited poorer PROs at a median of 4.8 years postoperation compared with those who had ≤2 dislocations before surgery, when adjusting for age, sex, BMI, CDI, TT-TG distance, and trochlear sulcus angle.

Objectives To evaluate results of open reduction and internal fixation (ORIF) of loose osteochondritis dissecans (OCD) fragments of the trochlea including identification of any cases of fixation failure and assessment of post-operative patient-reported outcomes and activity level. Methods A retrospective chart review of OCD fixation surgeries performed between 2010 and 2021 identified 12 patients who underwent ORIF of loose OCD trochlear fragments. Patient demographics, history, imaging findings, surgical factors, and skeletal maturity were all collected. Primary outcome measures included reoperation for fixation failure, Knee Osteoarthritis Outcome Scores (KOOS), and Marx scores. Results The 12 patients (12 knees) with a mean age of 17.7 ± 6.4 years (range, 13-37 years) were included in the case series. Mean trochlear OCD size was 3.20 cm2 (range, 1.69-5.06 cm2) with mean follow-up of 78.9 months (range, 8 – 145). Failure of fixation occurred in. Failure of fixation occurred in 2 patients (17%). Of the 10 patients (83%) who completed PROs, the mean KOOS global score for all patients was 86.8 ± 16.3, symptoms/stiffness sub score 90.0 ± 11.0, pain 91.2 ± 12.1, Functions of daily living 95.5 ± 8.3, Sports/recreation 82.0 ± 23.9, quality of life 75.7 ± 28.6, and a mean Marx activity score of 10.5 ± 4.9. Conclusion ORIF of loose OCD lesions of the trochlea is associated with a low risk of failure of fixation and acceptable patient-reported outcomes.

We hypothesize that larger prior tunnel size is associated with an increased risk of failure of single-stage revision anterior cruciate ligament reconstruction (ACLR) as defined by the performance of a re-revision (third) ACLR on the index knee. Retrospective review identified 244 patients who underwent single-stage revision ACLR at a single center with available preoperative radiographs. Patient and surgical factors were extracted by chart review. The maximum diameter of the tibial tunnel was measured on lateral radiographs and the maximum diameter of the femoral tunnel was measured on anteroposterior radiographs. Record review and follow-up phone calls were used to identify failure of the revision surgery as defined by re-revision ACLR on the index knee. One hundred and seventy-one patients (70%) were reviewed with a mean of 3.9 years follow-up. Overall, 23 patients (13.4%) underwent re-revision surgery. Mean tibial tunnel size was 12.6 +/- 2.8 mm (range: 5.7-26.9 mm) and mean femoral tunnel size was 11.7 +/- 2.8 mm (range: 6.0-23.0 mm). Re-revision risk increased with tibial tunnel size. Tibial tunnels 11 mm and under had a re-revision risk of 4.2%, while tunnels > 11 mm had a risk of 17.1% (relative risk: 4.1, p = 0.025). No significant association between femoral tunnel size and re-revision risk was noted. Patients with prior tibial tunnels > 11mm in diameter at revision surgery had significantly increased risk of re-revision ACLR. Further studies are needed to explore the relationship between prior tunnel size and outcomes of revision ACLR.

BACKGROUND:Elevated posterior tibial slope (PTS) has been identified as an important risk factor in anterior cruciate ligament (ACL) injuries and ACL graft failures. The cutoff value to recommend treatment with slope-reducing osteotomy remains unclear and is based on expert opinion and small case series.PURPOSE:(1) To determine whether there is a difference in PTS shown on lateral knee radiographs and magnetic resonance imaging (MRI) scans in a group of patients who experienced revision ACL graft failure versus a control group of patients who underwent successful revision ACL reconstruction, (2) to identify cutoff values of PTS measurements that predict risk of revision ACL graft failure, and (3) to examine whether there is a correlation between radiographic and MRI measurements of PTS.STUDY DESIGN:Case-control study; Level of evidence, 3.METHODS:A total of 38 patients who experienced revision ACL graft failure were identified from a revision ACL database. These patients were matched 1:1 by age, sex, and graft type to a group of 38 control patients who underwent revision ACL reconstruction with no evidence of graft failure at a minimum 2 years of follow-up. Medial and lateral PTS were measured by lateral knee radiographs and MRI scans of the affected limb. Demographics, surgical characteristics, and PTS were compared between the groups. The optimal cutoff values of medial and lateral PTS per radiographs and MRI scans for predicting increased risk of revision ACL graft failure were determined by receiver operating characteristic curves. Conditional multivariable logistic regression was used to assess the relative contribution of PTS cutoff values as a predictor of revision graft failure.RESULTS:The mean PTS values in the failure group were significantly higher than those in the control group on radiographs (medial, 13.2°± 2.9° vs 10.3°± 2.9°; P < .001; lateral, 12.9°± 3.0° vs 9.8°± 2.8°; P < .001) and MRI scans (medial, 7.2°± 3.1° vs 4.8°± 2.9°; P < .001; lateral, 8.4 ± 3.1° vs 5.9 ± 3.0°; P < .001). A radiographic medial PTS ≥14° had the highest increased risk of revision ACL graft failure with sensitivity equal to 50% and specificity to 92.1% (odds ratio, 18.71; 95% CI, 2.0-174.9; P = .01).CONCLUSION:Elevated PTS was a significant risk factor for revision ACL graft failure. Patients with radiographic medial PTS ≥14° had 18.7-times increased risk of revision ACL failure.

Purpose To evaluate the association of posterior tibial slope (PTS) with anterior cruciate ligament (ACL) reinjury following primary ACL reconstruction. Methods PubMed, Scopus, Embase, and CINAHL databases were searched from inception through March 1, 2021, to retrieve relevant studies. Comparative studies reporting PTS measurements in a cohort of patients experiencing ACL graft failure versus patients with intact primary ACL reconstruction or studies comparing patients undergoing revision ACL reconstruction versus primary ACL reconstruction were included for analysis. A random-effects model was used to calculate the overall standardized mean difference (SMD) between groups. The following inclusion criteria were used: English language; full text available; Level I, II, or III evidence; studies in humans; and skeletally mature patients. Results After we systematically screened 1,912 studies, 15 studies met the inclusion/exclusion criteria. Radiographic measurements were used in 6 studies reporting medial PTS in 411 ACL failures versus 2808 controls. Patients with ACL failure had significantly greater medial PTS compared with controls (SMD 0.50; 95% confidence interval [CI] 0.23-0.77; P < .001). Magnetic resonance imaging (MRI) was used in 9 studies reporting lateral PTS measurements in 641 patients with a failed ACL reconstruction compared with 705 controls. Seven of the MRI studies also measured medial PTS in 552 failures versus 641 controls. Patients with ACL failure had significantly greater lateral PTS on MRI (SMD 0.58; 95% CI 0.13-1.03; P = .012) and medial PTS on MRI (SMD 0.59; 95% CI 0.23-0.96; P = .001) compared with controls. Conclusions The present meta-analysis demonstrated that patients with elevated PTS on radiographs and MRI are at increased risk for ACL graft failure after primary ACL reconstruction. Level of Evidence Level III, meta-analysis of Level III studies.

The purpose of this study was to investigate the impact of articular cartilage damage on outcomes following medial patellofemoral ligament (MPFL) reconstruction. Record review identified 160 patients who underwent isolated MPFL reconstruction at a single institution between 2008 and 2016. Patient demographics, patellofemoral articular cartilage status at surgery, and patient anatomical measures from imaging were obtained via chart review. Patients were contacted and outcomes assessed through collection of Norwich Patellar Instability (NPI) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Marx activity score as well as an assessment for recurrent patellar dislocation. Outcomes of patients with grade 0–II patellofemoral cartilage damage were compared to those of patients with grade III–IV cartilage damage. One hundred twenty-two patients (76

Objectives: To assess the inter- and intra-rater reliability of the classification of the J-sign as "large" versus "small or none" as compared to another two-level system ("present" versus "absent") and a three-level system ("large," "small," or "none") and to identify anatomical and patient factors associated with the presence of a large J-sign. Methods: Forty patients (40 knees) with recurrent patellar instability were prospectively enrolled and recorded on video actively extending their knee while seating. Four raters classified patellar tracking on two separate occasions using three systems: 1) two groups: J-sign versus no J-sign; 2) three groups: large J-sign, small J-sign, or no J-sign; and 3) two groups: large J-sign versus small or no J-sign. The intra- and inter-rater reliability of each system was assessed using kappa statistics. Anatomical (trochlear dysplasia, tibial tubercle-trochlear groove (TTTG) distance, patellar height) and patient (Beighton score) factors as well as Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales were compared between patients with a large J-sign and patients with a small or no J-sign. Results: Inter- and intra-rater reliability were found to be highest with the two-level classification system of a large J-sign versus a small or no J-sign (inter-rater kappa = 0.76, intra-rater kappa = 0.75). Patients with a large J-sign had more severe trochlear dysplasia as assessed with the sulcus angle (p = 0.042) and were more likely to have a tight lateral retinaculum (p = 0.032) and an elevated Beighton score (p = 0.009). No significant differences in KOOS subscales were noted based on the presence of a large J-sign versus a small J-sign or no J-sign. Conclusion: Qualitative visual assessment of patellar tracking with the J-sign demonstrates substantial inter- and intra-rater reliability, particularly when utilizing a two-group classification system to identify knees with a large Jsign. Patients with a large J-sign demonstrate an increased incidence of a tight lateral retinaculum, generalized ligamentous laxity, and trochlear dysplasia. Level of evidence: Level III - cross-sectional study.

Background: Meniscal allograft transplantation improves functional and patient-reported outcomes in patients with meniscal deficiency without significant osteoarthritis. In addition, it is known that valgus malalignment of the knee can lead to meniscal and chondral damage, and surgery is often indicated to restore the mechanical axis and slow progression of osteoarthritis. Indications: Indications for this procedure include patients with symptomatic lateral meniscal deficiency with associated valgus deformity of the knee. Patient’s age must be less than 50 years, body mass index less than 35 kg/m 2 , meniscal deficiency, and ipsilateral pain with or without swelling. Ligament tears, focal cartilage loss, and malalignment are not contraindications if also corrected. Technique Description: We begin by removing the remaining lateral meniscus, taking care to leave a small peripheral rim of meniscus. A transpatellar tendon arthrotomy is performed, and the meniscal allograft is passed through the arthrotomy and into the knee. An inside-out repair is performed using vertical mattress sutures. The sutures are tightened and tied with the knee at 30° to 40° of flexion. The distal femoral osteotomy is then performed. An approach is made to the lateral femur, where initial guidewires are placed using fluoroscopic guidance. The initial saw cut is made about 75% of the way across the femur, and an osteotome is used to complete the osteotomy. Care is taken to preserve the far medial cortex. An adjustable wedge osteotome is placed to open the lateral cortex in accordance with the preoperative template. The cortical wedge is fashioned using the tibial allograft from the meniscal transplant and is placed into the osteotomy. The osteotomy is secured using a locking plate with locking screws, and this is confirmed in safe position using fluoroscopy prior to the conclusion of the case. Results: Patients will have effective deformity correction and alleviation of pain. Many patients can return to sport without restrictions following appropriate rehabhilitation. Conclusion: Lateral meniscal allograft transplantation with distal femoral opening wedge osteotomy is an effective treatment for symptomatic lateral meniscal insufficiency with associated valgus deformity of the knee in patients without osteoarthritis. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Objectives: Meniscus tears are among the most common knee injuries. Successful meniscus repair is vital to avoid articular cartilage damage and osteoarthritis. There are many factors that contribute to the outcome and prognosis of meniscus repair including patient and injury factors. The goal of this study was to identify demographic and socioeconomic factors that may influence patient outcomes after meniscus repair. It was hypothesized that income can impact meniscus repair outcomes. Methods: Retrospective review identified patients who underwent meniscus repair surgery between 2009 and 2018 at a single academic institution. Patients were included if they lived in the local metropolitan area. Chart review was undertaken to collect demographic and surgical data. Patients were split into two groups: the 16 wealthiest zip codes and 16 poorest zip codes based on adjusted gross income from the internal revenue service (IRS) in 2018. Patients were included in the analysis if KOOS and IKDC scores were available. An independent t-test was used to determine the difference in scores between the two groups. Results: 67 patients were included in the analysis. 23 were from low-income zip codes and 44 were from high income zip codes. The patients from the poorer zip codes had significantly lower KOOS and IKDC scores compared to patients from the wealthier zip codes. Chart review identified socioeconomic factors that limited access to care in the postoperative period in 5 patients from the poorer zip codes (21.74%). Among these patients 40% of them reported lack of access to physical therapy due inadequate insurance coverage, and 60% due to lack of transportation, inability to take time off work and personal or family problems. Conclusions: Socioeconomic status may significantly impact outcomes, like KOOS and IKDC scores, following meniscus repair. Further work with larger dataset would provide more insight into this important question and allow for controlling of potential confounding variables.

Purpose There is growing concern over the readiness of orthopedic surgical residents and fellows for independent surgical practice upon completion of their training. This study aims to explore orthopedic surgery (OS) trainees’ experience of accessing operative autonomy by eliciting their perceptions and techniques implemented to gain autonomy. Methods OS residents and fellows were invited to participate in focus group interviews via a convenience sampling approach. A non-faculty facilitator led the discussions using an interview guide to prompt conversation. All interviews were recorded, de-identified, and then transcribed. Three investigators iteratively analyzed transcripts to identify emerging themes until thematic saturation was achieved. All interviews were performed at Ohio State University Wexner Medical Center, an academic medical institution, in Columbus, Ohio. Results A total of 16 residents and 2 fellows participated. Two themes emerged: (1) optimal setting: trainees were allowed more operative autonomy in trauma and on-call cases than elective cases, though they perceived it was their responsibility to earn autonomy; (2) techniques: two techniques promote trainees’ access to autonomy, including trainee-initiated techniques (i.e., building relationship, preoperative planning, knowing attending preferences, and effective communication); and (3) faculty-initiated techniques (i.e., setting expectations, indications conference, and providing graduated autonomy). Conclusions Our study findings suggest OS trainees tend to access least autonomy in elective OS cases. Although trainees perceived earning autonomy as their responsibility, faculty and resident development is recommended to enhance teaching and learning techniques to increase trainees’ practice readiness.

Background: There are few studies assessing the impact of age at time of surgery on meniscus repair failure risk and patient-reported outcome scores. We sought to determine whether age at time of meniscus repair surgery affects failure risk and patient-reported outcome scores. Methods: Patients who underwent meniscus repair during 2006-2013 were evaluated for meniscus repair failure and patient-reported outcome scores using the Knee Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) score, and Marx Activity score at mean follow-up 6.5±2.0 yr post-operative. A multivariable linear regression analysis was used to assess the influence of patient age on patient-reported outcome scores following meniscus repair. Results: A total of 170 patients with mean age 27.8±10.1 yr (59% male) were identified, including 29 patients age 18 and younger and 141 patients over 18. Increasing patient age was associated with significantly lower IKDC ( P =0.027), KOOS-ADL ( P =0.003), and Marx activity scores ( P <0.001). Repair failure occurred in 46 patients (27.1%) overall, including 7 failures (24.1%) in patients 18 and under and 39 failures (27.7%) in patients over 18. The logistic regression analysis demonstrated no association between age and meniscus repair failure risk when controlled for ACL reconstruction and BMI ( P =0.69). Conclusion: Increased age is associated with poorer IKDC, KOOS-ADL, and Marx Activity scores following meniscus repair. However, there is no difference in failure of healing of meniscus repair between adolescent patients and adults. Level of Evidence: III

The purpose of this study was to evaluate the relationship between the number of all-inside meniscal repair implants placed and the risk of repair failure. We hypothesized that the use of higher numbers of all-inside meniscus repair implants would be associated with increased failure risk. A retrospective chart review identified 351 patients who underwent all-inside meniscus repair between 2006 and 2013 by a sports medicine fellowship-trained orthopaedic surgeon at a single institution. Patient demographics (age, body mass index [BMI], sex) and surgical data (number of implants used, concomitant anterior cruciate ligament reconstruction [cACLR], and tear type/size/location) were recorded. Patients who received repairs in both menisci or who had follow-up < 1-year postoperatively were excluded. Repair failure was identified through chart review or patient interviews defined as a revision surgery on the index knee such as partial meniscectomy, total knee arthroplasty, meniscus transplant, or repeat repair. Logistic regression modeling was utilized to evaluate the relationship between the number of implants used and repair failure. A total of 227 all-inside meniscus repairs were included with a mean follow-up of 5.0 ± 3.0 years following surgery. Repair failure was noted in 68 knees (30.3%)-in 28.1% of knees with fewer than four implants and in 35.8% of knees with four or more implants (p = 0.31). No significant increase in failure was observed with increasing number of all-inside medial (odds ratio [OR]: 1.15; 95% confidence interval [CI]: 0.79-1.7; p = 0.46) or lateral (OR: 0.86; 95% CI: 0.47-1.57; p = 0.63) implants after controlling for patient age, BMI, cACLR, tear type, or size. Tears of the lateral meniscus located in the red-white and white-white zones had lower odds of failure (OR: 0.14; 95% CI: 0.02-0.88; p = 0.036) than tears within the red-red zone, and patients with cACLR had lower odds of repair failure (OR: 0.40; 95% CI: 0.18-0.86, p = 0.024) than those without. The number of all-inside implants placed during meniscus tear repair did not affect the likelihood of repair failure leading to reoperation after controlling for BMI, age, tear type, size, location, and cACLR. LEVEL OF EVIDENCE:  III.

Revision anterior cruciate ligament reconstruction is an increasingly common procedure, with 2-stage surgery often required to address large bone defects and malpositioned tunnels. The arthroscopic bone grafting technique described herein uses morselized allograft bone to provide reproducible fill of asymmetrical bone defects without autograft harvest or additional loss of native bone. The second stage of the anterior cruciate ligament reconstruction can typically proceed 6 months following bone grafting.

Abstract Meniscus root tears are important to recognize early given their potentially devastating consequences on joint health. This injury results in the lost ability of the meniscus to transfer axial loads into hoop stress; therefore, it is functionally equivalent to a complete meniscectomy. This causes rapid progression of osteoarthritis and increased need to total knee arthroplasty in a previously healthy joint. Despite these consequences, root tears have only been discussed in the orthopedic literature in the last 10 to 15 years and have not been routinely integrated into nonoperative sports medicine education. It is important for all nonoperative sports medicine providers to properly diagnose and triage this injury early in its course to maximize joint preservation efforts. The goal of this manuscript is to review the anatomy, presentation, natural history, imaging, and treatment options for meniscal root tears.

Objectives: Anterior closing wedge proximal tibia osteotomy (ACWPTO) is an effective treatment for patients with elevated posterior tibial slope (PTS) and recurrent anterior cruciate ligament (ACL) injuries. However, the preoperative planning and surgical execution can be challenging, especially with limited surgeon experience and training. The purpose of this study was to evaluate the initial design of a 3D printed patient-specific cutting guide (PSG) for performing ACWPTO in an animal model. It was hypothesized that the PSG for ACWPTO will more accurately achieve the desired PTS correction compared to a traditional free-hand (FH) technique. Methods: Thirty cadaveric porcine knees underwent lateral radiographs and computed tomography (CT) scans, and were randomly assigned to ACWPTO by PSG or FH technique. Three knees within each group were then assigned to a 10°,12°,14°,16° or 18° correction. Knees assigned to the PSG group then underwent 3D modeling and a PSG was created in SolidWorks to complete the desired PTS correction (Figure 1). Knees assigned to the FH group were templated by an experienced orthopedic surgeon for performing ACWPTO by measuring a pre-determined wedge of bone to be removed from the anterior tibia. Surgeries were then performed by an experienced (attending physician), intermediate (resident physician), and novice surgeon (medical student). Each surgeon performed ACWPTO using the PSG and FH technique for each of the intended angles of correction (10°,12°,14°,16°,18°). Following ACWPTO, post-operative radiographs and CT scans were taken to measure the PTS and the accuracy was determined as the difference between the planned and actual PTS correction (Figure 2). The accuracy, surgical time, and radiation exposure were compared between surgeons using ANOVA. Further analyses to compare the variables of interest between the FH and PSG techniques were conducted using independent samples t-tests. Results: All data are summarized in Tables 1 and 2. Overall, we found the PSG to have significantly faster surgical time (6.4 +/- 2.2 minutes versus 12.0 +/- 3.9 minutes, p < 0.001) and less radiation exposure (8.7 +/- 4.9 mGy versus 58.7 +/- 28.1 mGy, p < 0.001). While the PSG trended towards increased accuracy with radiographic measurements of PTS, this did not reach statistical significance (1.6 +/- 1.6 degrees versus 2.9 +/- 2.0 degrees, p = 0.059). The highest accuracy was found for the resident (intermediate) surgeon using the PSG (0.5 +/- 0.5 degrees), which was significantly more accurate than FH technique for this surgeon (3.6 +/- 2.5 degrees, p = 0.026). Based on CT measurements of medial and lateral PTS we found the FH technique to be as accurate as the PSG (Table 2). Conclusions: One reason for the discrepancy between radiographic and CT measurements may be the lack of standardized methods for measuring PTS in porcine knees. The proximal tibia articular surface has a more complex geometry as compared to human knees, which did make measuring consistent landmarks challenging and is one of the primary limitations of this study. Other limitations of this study include the margin of error in the design of the 3D printed PSG, and accurate placement of the PSG on the proximal tibia. Guide placement was challenging if any cartilage remained around the tibial tubercle as this was not templated in the CT design. Also, PTS measurements can be highly dependent on limb rotation and observer experience. Despite these limitations, this study demonstrated the feasibility of a 3D printed PSG for performing ACWPTO in an animal model. This PSG was as accurate as the free-hand technique based on CT measurements and trended towards improved accuracy based on radiographic measurement of PTS. Future studies are planned to investigate this design in human cadaveric specimens. Table 1. Comparison of Results by Surgeon (Novice vs. Intermediate vs. Expert) Figure 1. A) 3D model of porcine tibia created in SolidWorks to create a patient specific cutting guide to perform anterior closing wedge tibial osteotomy. B) 3D printed patient specific cutting guide for anterior closing wedge tibial osteotomy. Table 2. Comparison of Results by Surgical Technique (Free-hand vs. Patient-Specific Guide) Figure 2. A) Pre-operative radiograph with measurement of posterior tibial slope. B) Post-operative radiograph after anterior closing wedge proximal tibial osteotomy performed with measurement of posterior tibial slope.