Background: Ulnar collateral ligament (UCL) reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, and there remain limited data on off-speed pitch performance in those that return to play after reconstruction.Purpose/Hypothesis: The purpose of this study was to evaluate the effect of primary UCLR on curveball (CB) and change-up (CU) pitch performance in terms of velocity along with novel pitching metrics including spin rate, hard-hit rate, and whiff rate. It was hypothesized that post-UCLR off-speed pitch spin rates, velocity, and whiff rate would decrease significantly compared with pre-UCLR levels, while hard-hit rates would increase.Study Design: Cohort study; Level of evidence, 3.Methods: Pitchers who underwent UCLR and returned to MLB level of play were identified from public records from 2016 to 2019. The Statcast system was used to collect spin rate, velocity, hard-hit, and whiff rate data for CB and CU pitches for preinjury seasons, as well as the first 2 seasons after return from UCLR. A matched-pair analysis was performed by matching each pitcher to an uninjured healthy pitcher from the same draft class and round.Results: A total of 29 pitchers met inclusion criteria and threw the pitches of interest. There were no statistically significant changes in CB or CU mean spin rate, pitch velocity, hard-hit rate, or whiff rate when comparing preinjury levels with the first and second seasons played after reconstruction. There were no significant differences in any pitching metrics when comparing the UCLR cohort with the healthy matched-pair cohort. The mean total number of CU pitches significantly decreased in the first season after UCLR (154.0 vs 67.9; P = .04) and compared with the matched-pair cohort at 1 year (67.9 vs 233.2; P = .001). Pitchers also threw fewer total pitches in the first season after returning from UCLR compared with preinjury baselines and healthy matched pairs.Conclusion: The results of this study demonstrate that pitchers who undergo UCLR and return to the MLB level can expect similar off-speed pitch performance in comparison with their preinjury levels and with pitchers without UCL injury.

BACKGROUND:There is a paucity of literature evaluating (1) changes in lateral compartment tibiofemoral contact mechanics and lateral meniscal function and (2) the effect of varying repair constructs in treating partial-thickness (type 3) lateral meniscal oblique radial tears (LMORTs). HYPOTHESIS:(1) Type 3 LMORTs would significantly alter lateral compartment contact mechanics and meniscal function when compared with the intact state, and (2) tibia-based suture anchor repair would more effectively restore these metrics to native levels when compared with capsular-based side-to-side repair or debridement. STUDY DESIGN:Controlled laboratory study. METHODS:Eight nonpaired fresh-frozen human cadaveric knees were utilized for this study. Each specimen was tested across 5 states in the following order: intact lateral meniscus, LMORT type 3 (partial thickness) tear created 12 mm lateral to the root attachment, tibia-based suture anchor fixation, capsular-based side-to-side repair, and debridement. For each state, 4 knee flexion angles were tested in random order: 0°, 30°, 60°, and 90° with 500 N of axial load. The following were recorded for each state: contact area, mean contact pressure, peak contact pressure of the lateral compartment, lateral meniscal extrusion, and 3-dimensional lateral meniscal anterior root forces (via use of a novel 3-axis sensor). Differences in means of outcomes were compared by 2-way repeated measures analysis of variance. RESULTS:Type 3 LMORTs were associated with significantly increased contact pressures and extrusion at all flexion angles and decreased contact area at high knee flexion angles as compared with the intact state. The tear state was also associated with significantly decreased forces experienced at the lateral meniscal anterior root attachment versus the intact state. Tibia-based suture anchor and capsular-based side-to-side repair restored contact mechanics, extrusion, and anterior root forces to the intact state, with no significant difference between the repair conditions. Debridement was associated with worse or no better outcomes than tear state alone. CONCLUSION:In a cadaveric model, type 3 LMORTs significantly alter tibiofemoral joint mechanics and lateral meniscal force transmission, and repair of these tears restores the native state, regardless of repair construct. Clinically, this study provides biomechanical support for the repair of type 3 LMORTs at the time of anterior cruciate ligament reconstruction. CLINICAL RELEVANCE:This study provides data regarding the effects of type 3 LMORTs and LMORT repair on tibiofemoral contact mechanics and meniscal function. The results of our study provide additional biomechanical justification for LMORT repair at the time of anterior cruciate ligament reconstruction.

BACKGROUND:Posterior medial meniscus root tears are commonly treated with a transtibial pull-out (TO) repair, but significant postoperative meniscal extrusion has been reported. Recently, knotless adjustable suture anchor fixation has been introduced to treat root tears. This anchor-based fixation demonstrates less cyclic displacement than a TO repair. However, it is unknown how meniscal extrusion and contact mechanics compare between these 2 repair techniques when the meniscus endures cyclic tibiofemoral loading. HYPOTHESIS:Suture anchor repair will demonstrate reduced meniscal extrusion and lower medial compartment pressure at the 1000th cycle compared with the TO repair. STUDY DESIGN:Controlled laboratory study. METHODS:Eight pairs of cadaveric knees were used to compare extrusion and contact pressure between transtibial fixation and suture anchor repair techniques for medial meniscus posterior root tears. Each specimen underwent cyclic compressive loading (0th, 100th, 500th, and 1000th cycles). Medial meniscal extrusion was assessed with the knee at full extension using ultrasound, and medial compartment contact pressures were evaluated using pressure sensors. Statistical analyses included paired t tests and repeated-measures analysis of variance with an alpha level set at .05. RESULTS:The suture anchor repair technique demonstrated significantly lower absolute and relative medial meniscal extrusion compared with transtibial fixation repair after 500 and 1000 cycles of loading (P = .012 and P = .001, respectively). Similarly, mean medial compartment pressures were significantly lower in the suture anchor repair group compared with the transtibial fixation repair group after 1000 cycles (P = .028). No significant differences were found in peak pressures between the 2 repair techniques. CONCLUSION:The suture anchor repair demonstrated lower medial meniscal extrusion and reduced medial compartment contact pressures after time-zero cyclic loading. This biomechanical profile may be important for increasing the likelihood of healing and may translate to improved long-term outcomes for patients undergoing meniscus root repair. CLINICAL RELEVANCE:Understanding the biomechanical differences between repair techniques at time zero may be crucial for optimizing surgical outcomes and minimizing the risk of long-term joint degeneration after meniscus root tears. Future clinical studies should further investigate these findings in live patient populations to validate their effect on root healing, functional outcomes, and long-term osteoarthritis progression.

BACKGROUND:Partial meniscectomy provides short-term symptom relief but may accelerate the development of knee arthritis due to meniscal deficiency and altered joint biomechanics. While meniscal allograft transplantation (MAT) addresses complete meniscal loss, segmental meniscal transplantation may be an option for segmental loss. PURPOSE:To evaluate the biomechanical effect of segmental posterior medial meniscal transplantation on knee joint loading characteristics and compare it with the states of both intact meniscus and full MAT. STUDY DESIGN:Controlled laboratory study. METHODS:Ten fresh-frozen human cadaveric knees (mean age, 54.3 years) were tested under 4 conditions: intact meniscus, segmental medial meniscal loss, segmental posterior horn MAT, and full MAT. The knees were subjected to a 500-N compressive load at 0°, 30°, 60°, and 90° of knee flexion. Medial meniscal extrusion, contact area, mean contact pressure, and peak contact pressure were measured. Statistical analyses included 2-way repeated measures analysis of variance to assess the effects of meniscal state and knee flexion on biomechanical outcomes. RESULTS:Segmental medial meniscal deficiency significantly increased extrusion (+1.32 mm at 0°; +1.45 mm at 30°; +1.42 mm at 60°; and +1.67 mm at 90°) and mean pressure compared with the intact meniscus across all flexion angles. Both segmental transplantation and full transplantation restored extrusion to intact levels, with full transplantation demonstrating superior improvement in peak pressure at flexion angles >60° compared with segmental transplantation. Both segmental and full transplantation restored peak pressure to levels comparable with the intact meniscus at flexion angles ≥30°. CONCLUSION:Both segmental and full meniscal transplantation tested at the time of surgery restored meniscal extrusion and contact pressure to the intact state. CLINICAL RELEVANCE:Segmental transplantation may offer a promising approach for managing posterior medial meniscal deficiencies by restoring knee joint function and reducing meniscal extrusion.

BACKGROUND:Shoulder dislocations may lead to anterior glenoid rim fractures. An all-arthroscopic double-row repair, referred to as the bony Bankart bridge (BBB), has been proposed with superior biomechanical properties when compared to single-row repair techniques. The aim of the present study was to evaluate the minimum 10-year clinical and functional outcomes following BBB. METHODS:All consecutive patients who underwent arthroscopic BBB for the treatment of shoulder instability with an associated bony Bankart lesion by a single surgeon between December 2007 and February 2013 were eligible for inclusion. Preoperatively and minimum 10 years postoperatively, patient-reported outcome measures (American Shoulder and Elbow Surgeons score, short version of the Disabilities of the Arm, Shoulder, and Hand questionnaire, Single Assessment Numeric Evaluation, 12-Item Short-Form Health Survey Physical Component Summary, satisfaction with the postoperative result [1-10 scale with "10" indicating maximum satisfaction], and visual analog scale for pain), return to sport rates, and instability recurrence and revision surgery rates were evaluated. RESULTS:Eleven patients (100% male) with a mean age at the time of surgery of 48.0 (interquartile range: 31.0-62.0) years were evaluated 14.0 (11.0-14.0) years postoperatively. At long-term follow-up, significant improvements in shoulder function (American Shoulder and Elbow Surgeons score: 74.9 [30.8-90.8] vs. 100 [98.3-100], P < .001; Quick Disabilities of the Arm, Shoulder, and Hand: 13.6 [10.0-63.6] vs. 0.0 [0.0-6.8], P = .002; Single Assessment Numeric Evaluation: 50.0 [19.0-90.0] vs. 96.0 [89.0-99.0], P = .002) and physical health (12-Item Short-Form Health Survey Physical Component Summary: 44.1 [35.1-55.7] vs. 57.3 [56.5-58.5], P < .001) were observed. Median satisfaction with the postoperative outcome was high (10 [5.0-10]). Pain levels were low (visual analog scale for pain: 0 [0-0]). Ten patients reported their postoperative sporting activity level with the majority patients reporting sporting activity levels equal to or above (70.0%) their preinjury level. One patient (9.1%) reported a shoulder redislocation during follow-up. No patients underwent further surgery for instability or post-traumatic osteoarthritis. CONCLUSION:The arthroscopic BBB for patients with bony Bankart lesions is associated with excellent shoulder function, low pain levels, and high return to sport rates at long-term follow-up. One patient suffered a shoulder redislocation, but did not require revision surgery. No patients underwent further surgery for post-traumatic osteoarthritis during follow-up.

Background: The utilization of lateral extra-articular tenodesis (LET) augmentation for anterior cruciate ligament reconstruction has increased. Various fixation points have been recommended based on tactile and anatomic landmarks; however, there is limited reporting of the accuracy or precision of these techniques in clinical practice.Purpose/Hypothesis: The purpose of this study was to evaluate whether LET fixation points identified using anatomic landmarks and tactile techniques would fall within a predefined radiographic zone. It was hypothesized that the majority of LET fixation points would be inside the radiographic zone.Study Design: Cross-sectional study; Level of evidence, 4.Methods: Postoperative lateral knee radiographs of patients who underwent anterior cruciate ligament reconstruction with LET using a landmark-based technique without fluoroscopy between January 2018 and September 2023 were reviewed. Fixation points were measured by 2 raters based on their distance from an extension of the posterior femoral cortex line (PFCL) distally and a line perpendicular to the PFCL at the posterior condylar flare (PCF). Patients were excluded if the tunnel position could not be identified or if postoperative radiographs were malrotated. The mean LET position and percentage of points within the radiographic isometric zone, defined as 4 +/- 4 mm posterior and 4 +/- 3 mm anterior to the PFCL and 6 +/- 4 mm distal and 20 +/- 5 mm proximal to the PCF were calculated.Results: Complete data sets were obtained for 47 cases. The mean LET position was 6.4 +/- 7.1 mm (range, -9 to 27.3 mm) anterior to the PFCL and 1.8 +/- 7.6 mm (range, -16.7 to 12.6 mm) proximal to the PCF. Overall, 53% of LET fixation points were within the predefined radiographic zone. Of the malpositioned tunnels (n = 22), their locations relative to the radiographic zone were anterior (n = 18), posterior (n = 2), proximal (n = 1), and anterior and distal (n = 1).Conclusion: This study found large variation in the location of LET fixation points, and almost half of fixation points were outside the predefined radiographic zone. Accurate and precise tunnel placement is one of multiple factors that may be important to minimize the risk of lateral compartment overconstraint, anterior cruciate ligament graft failure, and anisometry leading to LET graft loosening.

Tibial-sided posterior cruciate ligament avulsion fractures are challenging injuries that often occur concomitantly in the setting of multiligament knee and other soft-tissue injuries. There is no consensus on the optimal surgical approach or timing of treatment for these injuries. This Technical Note describes the fixation of a displaced posterior cruciate ligament avulsion fracture with concomitant grade 3 medial collateral ligament injuries and bucket-handle lateral meniscus tears using open and arthroscopic techniques. This method allows the surgeon to address multiple pathologies in a single stage, although it requires strategic planning and rehabilitation considerations.

PurposeTo define the surgical anatomy of the meniscotibial ligament complex of the pediatric medial and lateral menisci and their relation to the proximal tibial physis and posterior joint capsule.MethodsFourteen pediatric cadaveric knee specimens (aged 3 months to 11 years) were dissected to clarify the relation of the posterior knee capsule, the meniscus, and the meniscotibial ligament complex. Metallic markers were placed marking the meniscotibial ligament capsular attachment on the proximal tibia. Specimens underwent computed tomography scanning to evaluate pin placement and relation to the physis. A digital measurement tool was used to measure the distances between the proximal tibial physis and the pins (placed at 5 points on both the lateral and medial menisci).ResultsIn each specimen, clear separation was noted between the posterior joint capsule from the meniscus and meniscotibial ligament complex in the medial and lateral compartments. There was an increase in the distance between the proximal tibial physis and the insertion points of the meniscotibial ligament complex with increasing specimen age. For both the medical and lateral menisci in group 1, the median meniscotibial ligament insertion points were often less than 7 mm (interquartile range, 0.00-7.8 mm) away from the physis. The median meniscotibial ligament insertion points in group 2 tended to be farther from the physis but always less than 20 mm (interquartile range, 2.5-17.5 mm)—and as close as less than 5 mm (lateral posterior root).ConclusionsIn this anatomic study of pediatric knees, we observed a distinct recess/cul-de-sac space between the posterior knee capsule and meniscal attachments in all specimens. This defines a distinct plane between the posterior knee capsule and the meniscotibial ligament complex, with a distance between the physis and meniscotibial ligament capsular attachments that increases with age.Clinical RelevanceThe anatomic parameters evaluated in our study should be considered as future meniscal repair and transplantation techniques aim to restore the meniscal anatomy, stability, and mobility provided by the meniscotibial ligament complex and capsule structures.

Purpose: The purpose of this systematic review was to evaluate outcomes and complica-tions rates between inlay and onlay patellofemoral arthroplasty (PFA). Methods: According to the PRISMA statement, 42 studies with 2552 patients were included. Data considered for quantitative analysis consisted of the Knee Society Score (KSS), the range of motion (ROM), the visual analogue score (VAS), and the Western Ontario and McMaster Universities questionnaire (WOMAC). Complications and revision surgery were considered. Results: Data on postoperative KSS showed no differences between the groups. The ROM was evaluated in 8 studies for 70 and 331 inlay and onlay PFA, respectively. Onlay group was favorable in terms of postoperative ROM. Postoperative VAS was available for 64 inlay and 110 onlay and no differences were found. Data on postoperative WOMAC were avail-able for 49 inlay and 527 onlay PFA and inlay group showed better scores. A statistically significant higher rate of instability, persistent pain, malposition, stiffness, deep infection, disease progression, and wear of the patellar component were noted in the inlay group. A higher rate of lateral release was noted in the onlay group. A higher number of manipula-tions under anesthesia was noted in the inlay group. The revision to total knee arthroplasty was reported more frequently in the inlay group. Conclusion: A higher rate of conversion to total knee arthroplasty and complication rates after inlay technique was found. The potential of achieving better WOMAC scores with the inlay technique should be weighed against the higher complication and revision rates compared to the onlay technique. Level of Evidence: IV. (c) 2023 Elsevier B.V. All rights reserved.

Major league baseball (MLB) pitchers are at risk of numerous injuries during play, and there is an increasing focus on evaluating their performance in the context of injury. Historically, performance after return to play (RTP) from injury has focused on general descriptive statistics, such as innings or games played, or rate statistics with inherent variability (eg, earned run average, walks and hits per inning pitched, strikeouts per 9 innings, or walks per 9 innings). However, in recent years, MLB has incorporated advanced technology and tracking systems in every stadium, allowing for more in-depth analysis of pitcher-specific data that are captured with every pitch of every game. This technology allows for the ability to delve into the pitching performance on a basis that is more specific to each pitcher and allows for more in-depth analysis of different aspects of pitching performance. The purpose of this narrative review was to illustrate the current state of injury recording for professional baseball pitchers, highlight recent technological advances in MLB, and describe the advanced data available for analysis. We used advanced data in the literature to review the current state of performance analysis after RTP in MLB pitchers after injury. Finally, we strived to provide a framework for future studies to more meticulously assess RTP performance given the current available resources for analysis.

The effect of serotonin on the fluidity of the tegumental membranes of adult male Schistosoma mansoni was assessed by the fluorescence recovery after photobleaching technique. It was demonstrated that the translational diffusion of 5-N'-octadecanoyl aminofluorescein is reduced by a mechanism involving G-protein coupled activation of adenylate cyclase and lowering of intracellular calcium concentration. Furthermore, the lateral diffusion coefficient and the mobile fraction appear to be controlled by calcium and cAMP dependent pathways respectively. No change in the diffusion of the fluorescent phospholipid N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-phosphatidyl choline was observed, suggesting the two probes used here partition into two different domains that are under independent control. An increase in the amount of protein associating with a membrane cytoskeleton is also demonstrated.

To present a synthesis of recent literature regarding the treatment of patellofemoral arthritis Risk factors of PFJ OA include patella malalignment or maltracking, injury to supportive structures including the MPFL, dysfunction of hamstring and quadriceps coordination, lower limb alignment, trochlear dysplasia, patellar trauma, or ACL surgery. Special physical exam maneuvers include patellar grind test, apprehension test, and lateral patellar tilt angle. Radiographs that should be obtained first-line include weight bearing bilateral AP, lateral, and Merchant views. CT and MRI are used to assess trochlear dysplasia, excessive patellar height, and TT-TG distance. Non-operative management options discussed include non-pharmacologic treatment (patient education, self-management, physical therapy, weight loss), ESWT, cold therapy, taping, bracing, and orthotics. Pharmacologic management options discussed include NSAIDs, acetaminophen, oral narcotics, and duloxetine. Injection therapies include glucocorticoids, hyaluronic acid, PRP, and other regenerative therapies (BMAC, adipose, or mesenchymal stem cells). Other treatment options include radiofrequency ablation and botulinum toxin. The algorithm for the surgical treatment of PFJ OA can begin with arthroscopic assessment of the PF articular cartilage to address mechanical symptoms and to evaluate/treat lateral soft tissue with or without overhanging lateral osteophytes. If patients fail to have symptomatic improvement, a TTO can be considered in those patients less than 50 years of age or active patients >50 years old. In patients with severe PFJ OA, refractory to the above treatments, PFA should be considered. While early PFA design and technique were less than encouraging, more recent implant design and surgical technique have demonstrated robust results in the literature. Patellofemoral osteoarthritis is a challenging orthopedic problem to treat, in that it can often affect younger patients, with otherwise well-functioning knees. It is a unique entity compared to TF OA with distinct epidemiology, biomechanics and risk factors and treatment options.

BACKGROUND:Hip dislocation is a rare occurrence during sports but carries serious implications for athletes.PURPOSE:To systematically review treatment strategies and outcomes for hip dislocation in athletes, with the ultimate goal of providing sports medicine physicians with the information necessary to appropriately treat and counsel patients sustaining this injury.STUDY DESIGN:Systematic review; Level of evidence, 4.METHODS:PubMed, MEDLINE, and Embase were searched for studies relating to hip instability and athletics from January 1, 1989 to October 1, 2019. Abstracts and articles were evaluated on the basis of predefined inclusion and exclusion criteria. Inclusion criteria were the following: (1) data from ≥1 patients, (2) native hip dislocation or subluxation occurring during sports, (3) patients aged at least 10 years, and (4) written in English. Exclusion criteria were (1) patients younger than 10 years; (2) nonnative or postoperative hip dislocation or subluxation; (3) a native hip injury without dislocation or subluxation; (4) patients with dislocation or subluxation secondary to neuromuscular, developmental, or syndromic causes; (5) dislocation or subluxation not occurring during sports; (6) patients with physeal fractures; or (7) review articles or meta-analyses. Data were recorded on patient demographics, injury mechanism, treatment strategies, and clinical and radiographic outcomes. Where possible, pooled analysis was performed. Studies were grouped based on reported outcomes. Meta-analysis was then performed on these pooled subsets.RESULTS:A total of 602 articles were initially identified, and after screening by 2 reviewers, 27 articles reporting on 145 patients were included in the final review. There were 2 studies that identified morphological differences between patients with posterior dislocation and controls, including decreased acetabular anteversion (P = .015 and .068, respectively), increased prevalence of a cam deformity (P < .0035), higher alpha angles (P≤ .0213), and decreased posterior acetabular coverage (P < .001). No differences were identified for the lateral center edge angle or Tonnis angle. Protected postreduction weightbearing was most commonly prescribed for 2 to 6 weeks, with 65% of reporting authors recommending touchdown, toe-touch, or crutch-assisted weightbearing. Recurrence was reported in 3% of cases. Overall, 4 studies reported on findings at hip arthroscopic surgery, including a 100% incidence of labral tears (n = 27; 4 studies), 92% incidence of chondral injuries, 20% incidence of capsular tears, and 84% incidence of ligamentum teres tears (n = 25; 2 studies). At final follow-up, 86% of patients reported no pain (n = 14; 12 studies), 87% reported a successful return to play (n = 39; 10 studies), and 11% had radiographic evidence of osteonecrosis (n = 38; 10 studies).CONCLUSION:Various treatment strategies have been described in the literature, and multiple methods have yielded promising clinical and radiographic outcomes in patients with native hip dislocation sustained during sporting activity. Data support nonoperative treatment with protected weightbearing for hips with concentric reduction and without significant fractures and an operative intervention to obtain concentric reduction if unachievable by closed means alone. Imaging for osteonecrosis is recommended, with evidence suggesting 4- to 6-week magnetic resonance imaging and follow-up at 3 months for those with suspicious findings in the femoral head.

As youth sports participation has increased in recent years, injuries to the anterior cruciate ligament (ACL) are increasingly common in pediatric patients. Historically, ACL reconstructions were delayed in pediatric patients to avoid physeal damage with potential for possible leg-length discrepancy or angular deformity. Current research shows delaying reconstruction or choosing non-operative management is associated with increased rates of meniscal and chondral injuries, persistent knee instability, and low rates of return to previous activity. Early ACL reconstruction with techniques to avoid physeal growth disturbance is now widely accepted amongst physicians. The purpose of this review was to first describe the pediatric ACL in terms of relevant anatomy and biomechanics, physical exam, and diagnostic imaging. Secondly, the importance of skeletal age and concern for physeal injury is then discussed in the context of ACL reconstruction options by skeletal age and remaining growth potential.

Objectives: Anatomic meniscus repair is frequently performed in young patients to maximize joint preservation and long-term joint health. Increasingly, surgeons are considering the role and function of the meniscotibial ligament structures during meniscus repair and transplant. The purpose of this study was to determine the distance between the tibial insertion of the meniscotibial ligament capsular attachment and the proximal tibial physis in skeletally immature subjects. Methods: 14 pediatric knee cadaver knee specimens (ages 3 months to 11 years) were dissected to clarify the relationship physis and meniscus/meniscotibial ligament complex. Metallic markers were placed marking the meniscotibial ligament capsular attachment in specific domains (Figure 1). The specimens underwent CT scanning to evaluate pin placement and relationship to the physis. OsiriX was used to measure the distances between the proximal tibial physis and the pins (placed at 5 points on both the lateral and medial meniscus- anterior root, 12 o’clock, 3/9 o’clock, 6 o’clock and posterior root). Specimens were divided into two groups for analysis- Group 1: ages 3 months- 2 years (10 pediatric knee specimens: 8 male, 2 female), and Group 2: ages 10-11 years (4 pediatric knee specimens: 2 male, 2 female). Results: There was an increase in the distance between the proximal tibial physis and the insertion points of the meniscotibial ligament with increasing specimen age. For both the medial and lateral menisci, Group 1’s meniscotibial ligament insertion points were less than 10mm away from the physis. Group 2’s meniscotibial ligament insertion points tended to be further away from the physis, but less than 20mm away, and sometimes even as close as <5mm (lateral posterior root). (Figure 2). Conclusions: This anatomic study defines the relationship between the physis and meniscotibial ligament capsular attachments that increases with age. These anatomic parameters can be considered as future meniscus repair and reconstruction techniques seek to restore the meniscus anatomy, stability, and mobility provided by the meniscotibial ligament structures. This anatomic information and may be used by surgeons to develop techniques to perform meniscal repair/reconstruction in patients that utilize the meniscotibial ligament structures. Avoiding direct physeal injury during menisco-tibial ligament repair is possible. Figure 1. Medial (blue) and lateral (red) Meniscal pin Placement. Figure 2. Distance (mm) from physis to Meniscotibial Ligament pins on Medial and Lateral Meniscus.

BACKGROUND:Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, with variable reported effects on velocity and traditional rate statistics. Currently, no studies have evaluated spin rate in the context of return to play (RTP) after injury. Greater spin rate has become increasingly sought after in the baseball community, as it is believed to be a vital aspect of pitch effectiveness.PURPOSE/HYPOTHESIS:The purpose was to evaluate the effect of primary UCLR on fastballs (FB) and sliders (SL) of MLB pitchers in terms of spin rate, velocity, hard-hit rate, and whiff rate. It hypothesized that the post-UCLR FB and SL spin rates, velocity, and whiff rate would be significantly decreased versus their pre-UCLR levels, while the FB and SL hard-hit rates would be higher in comparison with pre-UCLR levels.STUDY DESIGN:Case series; Level of evidence, 4.METHODS:In total, 42 pitchers who underwent UCLR and returned to MLB play were identified from public records from 2016 to 2019. The Statcast system was used to collect spin rate, velocity, hard-hit rate, and whiff rate for 4-seam FB (4FB), 2-seam FB (2FB), and SL for pitchers in the preinjury year as well as the 2 years after return from UCLR. Data were analyzed using the appropriate statistical tests.RESULTS:A total of 36 pitchers met the inclusion criteria, and 31 of the eligible 36 players (86.1%) were able to return to MLB pitching (RTP). There were no significant decreases for 4FB, 2FB, or SL in spin rate, measured in revolutions per minute (rpm), when comparing preinjury levels with the first and second seasons after return. There was a significant decrease in velocity for the 2FB in the first season (92.9 vs 93.7 miles per hour [mph]; P = .045) but not the second season (93 mph; P = .629) after RTP in comparison with pre-UCLR levels. For the 2FB, there was a significant increase in spin rate between preinjury and RTP season 2 (2173.5 vs 2253 rpm; P = .022). For the SL, there was a significant increase in spin rate between preinjury and RTP season 2 (2245.1 vs 2406 rpm; P = .016).CONCLUSION:A cohort of MLB pitchers who underwent UCLR and returned to the MLB level demonstrated no significant decreases in the spin rate, velocity, whiff rate, or hard-hit rate of 4FB, 2FB, or SL at 2 years after UCLR.