Medial Ulnar Collateral Ligament Reconstruction With Allograft Provides Excellent Clinical Outcomes, High Rates of Return to Play, and a Low Incidence of Postoperative Complications: A Systematic Review.

PURPOSE: To perform a systematic review evaluating clinical outcomes in patients undergoing medial ulnar collateral ligament reconstruction (MUCLR) with soft-tissue allograft. METHODS: A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary outcomes evaluated were patient-reported outcome scores, return to play (RTP) rates, incidence of postoperative complications, and rates of graft rupture or mechanical failure. RESULTS: The literature search identified 395 articles, and 5 studies met final inclusion criteria after full-text review. A total of 274 patients were analyzed in the included studies and follow-up ranged from 3.0 to 7.6 years. Two studies (number of patients = 141) reported outcomes exclusively of MUCLR with allograft, whereas 3 studies (number of patients = 133) reported outcomes in patients undergoing MUCLR with either allograft or autograft. Allograft sources included gracilis, semitendinosus, plantaris, peroneus longus, and palmaris longus. Level of patient athletic competition ranged from recreational athletes to the professional level; however, nonathletes in the setting of trauma were also included. The RTP rate after MUCLR with soft-tissue allograft was 95.3%, and 89.3% of patients returned to a similar or greater level of play postoperatively. The Timmerman-Andrews score was reported in 2 studies, and the means postoperatively ranged from 94.55 to 97. Postoperative complication rates were low (range, 0% to 20%), and there were no reported incidences of allograft rupture or mechanical failure. CONCLUSIONS: Based on the available data, soft-tissue allograft for MUCLR in athletic patient populations provides excellent clinical outcomes, high rates of RTP, and low rates of postoperative complications and graft failure at short-term follow-up. There remains a lack of high-quality evidence directly comparing autograft versus allograft outcomes in elite overhead-throwing athletes to support allograft as an acceptable alternative for MUCLR in this patient population. LEVEL OF EVIDENCE: Level IV, systematic review of Level III-IV studies.

Outcomes following arthroscopic treatment of off-track Hill-Sachs lesions using fresh osteochondral allograft plugs: a case series.

BACKGROUND AND HYPOTHESIS: Osteochondral allograft (OCA) transplantation is a well-described technique for the treatment of large, engaging Hill-Sachs lesions (HSLs). Traditionally, OCAs are size-matched to the defect, which can be expensive and time-consuming, and the majority of described techniques require an open approach. Recently, an all-arthroscopic approach to Hill-Sachs OCA transplantation using premade plugs was described, eliminating the need for size-matching and graft harvest. The purpose of this study was to evaluate postoperative outcomes of patients who have undergone arthroscopic treatment of HSLs using premade OCA plugs. We hypothesized that these patients would have improved pain and function without recurrent instability. METHODS: A retrospective chart review was performed using operative reports for a single surgeon with search terms Hill-Sachs and allograft. Patients were excluded if an open approach was used or if graft harvest was performed. Postoperative imaging was reviewed to assess for graft incorporation and reconstitution of the HSL. Recurrent instability and reoperation were recorded. Patients completed surveys including the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score and the Western Ontario Shoulder Instability Index (WOSI). RESULTS: Five patients were identified through chart review and met inclusion criteria. All patients underwent concurrent labral repair and 2 patients underwent a concurrent open Latarjet procedure. Postoperative radiographs showed reconstitution of the HSLs in all patients. There were no complications in the postoperative period with no recurrent instability or reoperations in any patient. The average ASES score was 87% (higher score indicating better outcome) with standard deviation 9.7, and the average WOSI score was 27% (lower score indicating better outcome) with standard deviation 8.3. CONCLUSION: Favorable outcomes can be expected after arthroscopic treatment of Hill-Sachs lesions using premade OCA plugs. Further research is needed to assess larger patient cohorts and compare outcomes to size-matched approaches.

Performance and Return to Sport After Hip Arthroscopy in the National Basketball Association.

PURPOSE: To determine: (1) return to sport (RTS) rate in National Basketball Association (NBA) players following hip arthroscopy, (2) postoperative career length and games per season, (3) pre- and postoperative performance, and (4) postoperative performance compared with control players. METHODS: NBA athletes who underwent hip arthroscopy and matched controls were identified. RTS was defined as playing in at least 1 game after surgery. Player efficiency ratings were used for performance evaluation. Continuous variables of each group were compared using a 2-tailed paired samples Student t test for normally distributed data. χ2 was used to analyze categorical data. RTS was used as the primary outcome with statistical significance defined by a P value < .05. A Bonferroni correction was used to control for the remaining multiple comparisons with statistical significance defined by a P value ≤.008. RESULTS: Twenty-three players (24 hips) were analyzed (mean age 27.5 ± 3.1 years; mean experience in the NBA 5.8 ± 2.8 years at time of surgery). Small forwards (n = 8, 33.3%) represented the largest proportion of players that underwent hip arthroscopy. Twenty players (21 surgeries, 87.5%) were able to RTS in NBA at an average of 5.7 ± 2.6 months. The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2%. Players in the control group (5.2 ± 3.5 years) had a similar career length as (P = .068) players who underwent surgery (4.4 ± 3.0 years). There was no significant (P = .045) decrease in games per season following surgery. There was no significant difference in performance postoperatively compared with preoperatively (P = .017) and compared with matched controls following surgery (P = .570). CONCLUSIONS: The RTS rate for NBA athletes after hip arthroscopy is high. There was no decrease in games played, career lengths, or performance following hip arthroscopy in NBA players versus preoperatively and matched controls. LEVEL OF EVIDENCE: Level III case-control study.

Electromyographic Profile of the Shoulder During Stability Exercises With Kettlebells.

CONTEXT: Shoulder rehabilitation can be a difficult task due to the dynamic nature of the joint complex. Various weight training implements, including kettlebells (KB), have been utilized for therapeutic exercise in the rehabilitation setting to improve shoulder girdle strength and motor control. The KBs are unique in that they provide an unstable load and have been purported to promote greater muscle activation versus standard dumbbells. Recent literature has examined the efficacy of KB exercises for global strengthening and aerobic capacity; however, electromyographic data for shoulder-specific activities are lacking. OBJECTIVE: To examine muscle activation patterns about the rotator cuff and scapular musculature during 5 commonly-utilized KB exercises. DESIGN: Cross-sectional analysis of a single group. SETTING: Clinical biomechanics laboratory. PARTICIPANTS: Ten participants performed all exercises in a randomized order. MAIN OUTCOME MEASURES: Mean electromyographic values for each subject were compared between exercises for each target muscle. RESULTS: Significant differences (P < .05) between exercises were observed for all target muscles except for the infraspinatus. CONCLUSIONS: The data in this study indicates that certain KB exercises may elicit activation of the shoulder girdle at different capacities. Physical therapy practitioners, athletic trainers, and other clinical professionals who intend to optimize localized strengthening responses may elect to prescribe certain exercises over others due to the inherent difference in muscular utilization. Ultimately, this data may serve to guide or prioritize exercise selection to achieve higher levels of efficacy for shoulder strength and stability gains.

Superior Capsular Reconstruction for Massive Rotator Cuff Tear Leads to Significant Improvement in Range of Motion and Clinical Outcomes: A Systematic Review.

PURPOSE: To determine if arthroscopic superior capsular reconstruction for massive irreparable rotator cuff tears results in statistically significant and clinically significant improvement in patient-reported outcomes and shoulder range of motion with low graft failure, complication, and reoperation rates. METHODS: A systematic review was registered with PROSPERO and performed using PRISMA guidelines. PubMed, SCOPUS, and Cochrane databases were searched. Studies investigating superior capsular reconstruction in adults were included. Animal, cadaveric, and review studies, letters to the editor, and technique papers were excluded. Study methodological quality was analyzed using the Modified Coleman Methodology Score. Shoulder motion and patient-reported outcome scores were analyzed. Statistical significance was defined by P < .05, and clinical significance was defined by the minimal clinically important difference. RESULTS: Six articles (286 subjects, 292 shoulders, 67.7% males, mean age 63.4 ± 4.1 years, mean follow-up 25.7 ± 14.5 months) were analyzed. The methodological quality was fair (59.7 ± 13.8). Five studies reported significant improvement in the American Shoulder and Elbow Surgeons (ASES) score (mean range: 30-55, P < .001 for all). Visual analog scale (VAS) scores significantly improved in 3 studies (mean range: 2.5-5.9, P < .001 for 2 and P = .005 for 1). Shoulder forward flexion (mean range: 28°-56°, P < .001 for 2 and P = .04 for 1) significantly increased in 3 studies. One hundred percent of subjects from 2 studies had clinically significant improvement in ASES and VAS scores and shoulder forward flexion. Thirty-six subjects (14.2% of 254) had graft failure on magnetic resonance imaging (MRI). Eleven subjects (3.8%) had complications, and 34 (11.7%) underwent reoperation. CONCLUSIONS: Arthroscopic superior capsular reconstruction for massive irreparable rotator cuff tears results in statistically significant and clinically significant improvement in patient-reported outcomes and shoulder range of motion with low graft failure, complication, and reoperation rates at short-term follow-up in fair-quality studies. LEVEL OF EVIDENCE: Level IV, systematic review of Level III and IV studies.

Hamstring Autograft Versus Hybrid Graft in Anterior Cruciate Ligament Reconstruction: A Systematic Review of Comparative Studies.

PURPOSE: To compare (1) patient-reported outcomes, (2) objective knee measures of stability, (3) failures, and (4) reoperations after primary anterior cruciate ligament (ACL) reconstruction with semitendinosus-gracilis autograft versus autograft-allograft hybrid grafts. METHODS: We performed a systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Multiple databases were searched for studies that compared outcomes of ACL reconstruction with semitendinosus-gracilis autograft versus autograft-allograft hybrid grafts in adult human patients with minimum 2-year follow-up. Knee-specific patient-reported outcome scores, objective knee measures of stability, failures, and reoperations were reported for each study and compared between semitendinosus-gracilis autografts and hybrid grafts. Study heterogeneity and levels of evidence precluded meta-analysis. RESULTS: We analyzed 6 articles (544 patients; 54.5% male patients; mean age, 30.9 ± 3.9 years; mean follow-up period, 43.6 ± 15.5 months). Of 6 studies, 4 showed no significant differences in International Knee Documentation Committee and Lysholm scores between the semitendinosus-gracilis autograft and hybrid groups. Five of six studies showed no significant differences in KT-1000 measurements between groups. The risk of ACL failure ranged from 3.2% to 8.4% for semitendinosus-gracilis autografts and from 2.4% to 14.3% for hybrid grafts, with no study reporting a significant difference in failure rates between groups. The reoperation rate in the subjects undergoing ACL reconstruction with semitendinosus-gracilis autografts and hybrid grafts ranged from 2.8% to 10.3% and from 2.4% to 48.3%, respectively. In 5 of 6 studies, no significant differences in reoperation rates were found between groups. CONCLUSIONS: Most studies reported no significant differences in patient-reported outcome scores, objective knee measures of stability, and reoperation rates between semitendinosus-gracilis autografts and hybrid grafts. No significant difference in ACL failure rates was found between groups in any study. LEVEL OF EVIDENCE: Level III, systematic review of Level II and III studies.

Is There an Association Between Noncontact Anterior Cruciate Ligament Injuries and Decreased Hip Internal Rotation or Radiographic Femoroacetabular Impingement? A Systematic Review.

PURPOSE: To perform a systematic review to determine if there is (1) an association between decreased hip internal rotation and anterior cruciate ligament (ACL) tear rates; (2) an association between radiographic femoroacetabular impingement (FAI) and ACL tear rates; and (3) biomechanical evidence demonstrating increased strain in the ACL of patients with decreased hip internal rotation. METHODS: A systematic review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies investigating relationships between hip motion, hip radiographs, and ACL tear were sought. Studies with Levels of evidence I-IV were eligible for inclusion. Study methodology/evidence were evaluated using Methodological Index for Non-Randomized Studies (MINORS), Strengthening the Reporting of Observational Studies in Epidemiology (STROBE), and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. RESULTS: Eleven studies were analyzed (2 cadaveric in vitro models, 8 clinical studies measuring hip internal rotation (2 concurrently assessing radiographic FAI), and 1 clinical study assessing radiographic FAI alone). Mean MINORS, STROBE, and GRADE for the studies was 82.4%, 20.9 out of 22, and "low," respectively. A total of 959 subjects (84.8% male; mean age 23.6 ± 3.8 years) were analyzed. Overall, 378 subjects sustained 427 ACL tears (399 primary ACL ruptures, 28 reruptures). Six of 8 clinical studies identified a significant association between limited rotation (internal rotation [IR; loss greater than 10°-20°], external rotation [ER], or combined IR + ER [loss greater than 20°]) and ACL tears. Two studies found an association between ACL ruptures and radiographic cam/pincer impingement. Two cadaveric models found a significant association between ACL strain and limited hip internal rotation. CONCLUSIONS: This systematic review identified a significant association between ACL tear and both limited hip rotation and radiographic FAI. LEVEL OF EVIDENCE: Level IV, systematic review of Levels II-IV studies.

Current evidence advocates use of a new pathologic tibial tubercle-posterior cruciate ligament distance threshold in patients with patellar instability.

PURPOSE: To determine (1) whether a correlation exists between tibial tubercle-posterior cruciate ligament (TT-PCL) and tibial tubercle-trochlear groove (TT-TG) distances in patellar instability patients; (2) reliability when measuring TT-PCL distance; (3) whether TT-PCL distances measured on MRI are equivalent to those on CT; and (4) whether a correlation exists between TT-PCL distance and number of instability events or recurrence of instability following stabilization surgery. METHODS: A systematic review was performed using PRISMA guidelines. Clinical studies investigating the relationships of TT-PCL with TT-TG on CT and/or MRI in patellar instability patients were sought. English language studies with Levels of evidence I-IV were eligible for inclusion. RESULTS: Four studies (285 subjects [300 knees] with patellar instability [74.2% female; mean age 26.1 ± 8.2 years]; 114 controls [144 knees; 77% female; mean age 23.1 years]) were included. Mean TT-PCL of instability and control groups was 21.1 ± 4.1 and 18.8 ± 4.0 mm (p < 0.0001), respectively. Two studies reported significant positive (strong and moderate) correlations between TT-PCL and TT-TG MRI measurements in instability patients. All four investigations reported excellent interobserver and intraobserver reliability in MRI measurement of TT-PCL distance. No study compared TT-PCL distances on MRI and CT. No study assessed correlation between TT-PCL distance and number of instability events or recurrence of instability after surgery. CONCLUSION: A moderate-to-strong positive correlation exists between TT-PCL and TT-TG measurements taken from MRIs of patellar instability patients. There is excellent interobserver and intraobserver reliability when taking TT-PCL measurements using MRI. This review advocates use of a new pathologic TT-PCL threshold of 21 mm. LEVEL OF EVIDENCE: Level III, systematic review of Level II-III studies.

Critical Analysis of the Lever Test for Diagnosis of Anterior Cruciate Ligament Insufficiency.

PURPOSE: To critically analyze the "lever test" in detecting anterior cruciate ligament (ACL) tears and to compare its accuracy with the Lachman, anterior drawer (AD), and pivot shift tests. METHODS: From June 2014 to June 2015, 91 subjects were analyzed. Inclusion criteria were subjects aged 16 to 60 years, presenting after a knee injury with subjective swelling, or an objective effusion and an uninjured normal contralateral knee for comparison. Exclusion criteria included previous knee ligamentous reconstruction, fracture of the distal femur or proximal tibia, bilateral knee injuries, or known cruciate ligament tear. The Lachman, AD, pivot shift, and lever tests were performed in the office by 2 board-certified orthopaedic surgeons with patient awake. Examiners were blinded to the presence or absence of ACL injury. Magnetic resonance imaging was used to determine injury. Sensitivity, specificity, and accuracy were evaluated for all 4 tests. Accuracy was compared using χ-square and receiver operator curves. RESULTS: Average subject age was 28 ± 11 years (61 males, 30 females). Seventy-one (79%) had ACL tears diagnosed by magnetic resonance imaging. The sensitivity, specificity, and accuracy of the lever test were 83%, 80%, and 82%, respectively. Accuracy was not statistically different from the Lachman, AD, and pivot shift tests (P = .78, .99, .07, respectively). Subanalyses were performed based on the presence of another ligament tear, timing of injury, and the presence of a meniscus tear. Although the groups were smaller and thus underpowered, the results were reported. Neither the presence of another ligament tear nor the timing of the injury affected accuracy (P = .62 and P = .47); however, the presence of a meniscus tear decreased its accuracy (P = .003). CONCLUSIONS: The lever test showed high sensitivity, specificity, and overall accuracy in the detection of ACL tears. The accuracy of the lever test was not significantly different from the Lachman, AD, or pivot shift tests. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Arthroscopic Debridement for Primary Degenerative Osteoarthritis of the Elbow Leads to Significant Improvement in Range of Motion and Clinical Outcomes: A Systematic Review.

PURPOSE: The purpose of this investigation was to determine whether arthroscopic debridement of primary elbow osteoarthritis results in statistically significant and clinically relevant improvement in (1) elbow range of motion and (2) clinical outcomes with (3) low complication and reoperation rates. METHODS: A systematic review was registered with PROSPERO and performed using PRISMA guidelines. Databases were searched for studies that investigated the outcomes of arthroscopic debridement for the treatment of primary osteoarthritis of the elbow in adult human patients. Study methodological quality was analyzed. Studies that included post-traumatic arthritis were excluded. Elbow motion and all elbow-specific patient-reported outcome scores were eligible for analysis. Comparisons between preoperative and postoperative values from each study were made using 2-sample Z-tests (http://in-silico.net/tools/statistics/ztest) using a P value < .05. RESULTS: Nine articles (209 subjects, 213 elbows, 187 males, 22 females, mean age 45.7 ± 7.1 years, mean follow-up 41.7 ± 16.3. months; 75% right, 25% left; 79% dominant elbow, 21% nondominant) were analyzed. Elbow extension (23.4°-10.7°, Δ 12.7°), flexion (115.9°-128.7°, Δ 12.8°), and global arc of motion (94.5°-117.6°, Δ 23.1°) had statistically significant and clinically relevant improvement following arthroscopic debridement (P < .0001 for all). There was also a statistically significant (P < .0001) and clinically relevant improvement in the Mayo Elbow Performance Score (60.7-84.6, Δ 23.9) postoperatively. Six patients (2.8%) had postoperative complications. Nine (4.2%) underwent reoperation. CONCLUSIONS: Elbow arthroscopic debridement for primary degenerative osteoarthritis results in statistically significant and clinically relevant improvement in elbow range of motion and clinical outcomes with low complication and reoperation rates. LEVEL OF EVIDENCE: Systematic review of level IV studies.

Efficacy of Intra-articular Platelet-Rich Plasma Injections in Knee Osteoarthritis: A Systematic Review.

PURPOSE: To determine (1) whether platelet-rich plasma (PRP) injection significantly improves validated patient-reported outcomes in patients with symptomatic knee osteoarthritis (OA) at 6 and 12 months postinjection, (2) differences in outcomes between PRP and corticosteroid injections or viscosupplementation or placebo injections at 6 and 12 months postinjection, and (3) similarities and differences in outcomes based on the PRP formulations used in the analyzed studies. METHODS: PubMed, Cochrane Central Register of Controlled Trials, SCOPUS, and Sport Discus were searched for English-language, level I evidence, human in vivo studies on the treatment of symptomatic knee OA with intra-articular PRP compared with other options, with a minimum of 6 months of follow-up. A quality assessment of all articles was performed using the Modified Coleman Methodology Score (average, 83.3/100), and outcomes were analyzed using 2-proportion z-tests. RESULTS: Six articles (739 patients, 817 knees, 39% males, mean age of 59.9 years, with 38 weeks average follow-up) were analyzed. All studies met minimal clinical important difference criteria and showed significant improvements in statistical and clinical outcomes, including pain, physical function, and stiffness, with PRP. All but one study showed significant differences in clinical outcomes between PRP and hyaluronic acid (HA) or PRP and placebo in pain and function. Average pretreatment Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were 52.36 and 52.05 for the PRP and HA groups, respectively (P = .420). Mean post-treatment WOMAC scores for PRP were significantly better than for HA at 3 to 6 months (28.5 and 43.4, respectively; P = .0008) and at 6 to 12 months (22.8 and 38.1, respectively; P = .0062). None of the included studies used corticosteroids. CONCLUSIONS: In patients with symptomatic knee OA, PRP injection results in significant clinical improvements up to 12 months postinjection. Clinical outcomes and WOMAC scores are significantly better after PRP versus HA at 3 to 12 months postinjection. There is limited evidence for comparing leukocyte-rich versus leukocyte-poor PRP or PRP versus steroids in this study. LEVEL OF EVIDENCE: Level I, systematic review of Level I studies.

Radiographic Evidence of Hip Microinstability in Elite Ballet.

PURPOSE: To determine prevalence, magnitude, and predisposing radiographic features of hip subluxation in elite ballet dancers. METHODS: A cross-sectional investigation of professional male and female ballet dancers was performed using 5 plain radiographs. A "splits" anteroposterior (AP) radiograph was performed with legs abducted parallel to the trunk in the coronal plane (splits position; grand écart facial). Hip center position (HCP) was measured on standing AP pelvis and AP pelvis splits views and the difference calculated (subluxation distance) to determine prevalence and magnitude of femoral head subluxation. Student t test compared HCP on AP pelvis and splits radiographs. Pearson correlations were used to correlate splits HCP with radiographic measures of femoroacetabular impingement and dysplasia. RESULTS: Analyzing 47 dancers (21 men, 26 women; 23.8 ± 5.4 years), mean HCP on standing AP pelvis was 9.39 ± 3.33 mm versus 10.8 ± 2.92 mm on splits radiograph, with mean subluxation distance of 1.41 mm (P = .035). Forty-two dancers' femoral heads translated laterally with splits positioning, and 17 dancers (36%) exhibited a "vacuum sign" (bilateral in 71% of subjects with at least 1 hip vacuum sign). There was strong positive correlation (r = 0.461, P = .001) with splits HCP and alpha angle (Dunn 45°), and moderate negative correlation (r = -0.332, P = .022) with subluxation distance and neck-shaft angle. In men, splits HCP increased as lateral center edge angle (CEA) decreased (r = -0.437, P = .047), as anterior CEA decreased (r = -0.482, P = .027), as Tönnis angle increased (r = 0.656, P = .001), and as femoral head extrusion index increased (r = 0.511, P = .018). In women, there was moderate negative correlation (r = -0.389, P = .049) with subluxation distance and neck-shaft angle. CONCLUSIONS: Hip subluxation occurs during splits in most professional ballet dancers, with a significantly greater magnitude of subluxation in women than men. Subluxation magnitude increases with increasing alpha angle and decreasing neck-shaft angle. In men, the magnitude increases with severity of dysplasia. Women had subluxation regardless of acetabular morphology but increased subluxation with decreased neck-shaft angle. This provides radiographic support for hip microinstability in elite ballet. LEVEL OF EVIDENCE: Level IV, diagnostic.

Superior labrum anterior to posterior tears in throwing athletes.

Superior labrum anterior to posterior (SLAP) tears and partial undersurface tears of the rotator cuff are common in experienced throwers, may be adaptive, and are only occasionally symptomatic. Pain in the shoulder of a throwing athlete with an MRI-documented SLAP tear or partial undersurface tear of the rotator cuff can be managed nonsurgically, with attention to posterior capsular contracture, scapular dyskinesia, and rotator cuff strength. The results of the surgical repair of SLAP lesions in the throwing athlete, with or without rotator cuff repair, are inferior to those of nonsurgical treatment. The cause of pain in the throwing athlete must be accurately diagnosed without reliance on MRI findings.

The effect of progressive degrees of medial meniscal loss on stability after anterior cruciate ligament reconstruction.

Previous studies report conflicting results on whether loss of the medial meniscus compromises knee stability after reconstruction of the anterior cruciate ligament (ACL). The purpose of this study was to determine whether the degree of medial meniscus deficiency affects the stability of the ACL-reconstructed knee. Six cadaveric knees were arthroscopically reconstructed with bone-patellar tendon-bone autografts using an anatomic "footprint" technique. Knees tested were ACL-deficient and after reconstruction under three different meniscal states: with partial medial meniscectomy, subtotal meniscectomy, and meniscal root transection. Biomechanical testing was performed at 30 and 60 degrees of flexion under two loading conditions: (1) 134-N anterior tibial load termed anterior tibial translation (ATT) and (2) 10-Nm valgus load combined with 5 Nm of internal tibial torque termed provocative pivot maneuver (PPM). Knee kinematics was measured using a custom activity simulator, motion analysis system, and three-dimensional CT reconstructions. During both ATT and PPM loading, ACL deficiency resulted in a significant increase in anterior translation compared with knees with an intact ACL or those that had undergone ACL reconstruction (p < 0.05). Neither the addition of a partial nor subtotal medial meniscectomy led to increased instability. Only after medial meniscal root transection was increased instability of the ACL-deficient knee detected compared with intact, partial, or subtotal meniscectomy states (p < 0.01). In all states of meniscal deficiency, ACL reconstruction restored internal tibial rotation and anterior translation at 30 degrees to that of the intact knee (p > 0.05). Anatomic single bundle ACL reconstruction was able to restore knee stability in all conditions of medial meniscal deficiency.

All-Arthroscopic Treatment of Off-Track Hill-Sachs Lesions Using Fresh Osteochondral Allograft Plugs: "Rocks in a Stream".

Osteochondral allograft transplantation is a well-described technique for the treatment of large, engaging Hill-Sachs lesions. Traditionally, osteochondral allografts are size-matched to the defect, which can be expensive and time-consuming, and the majority of described techniques require an open approach. This Technical Note describes an all-arthroscopic approach to Hill-Sachs osteochondral allograft transplantation using premade osteochondral allograft plugs, eliminating the need for size-matching and graft harvest. This approach works not by anatomically filling the defect, but rather by bridging the defect to prevent it from engaging the glenoid.

The impact of ulnar collateral ligament tear and reconstruction on contact pressures in the lateral compartment of the elbow.

HYPOTHESIS: Complete ulnar collateral ligament (UCL) injury increases articular pressure and reduces contact area compared with the normal intact UCL. UCL reconstruction restores the contact area and contact pressure observed in the native joint. MATERIALS AND METHODS: Six male cadaveric elbows were mounted on a custom jig capable of simulating the 2 critical phases of the throwing motion during pitching. A contact sensor was placed through an anterior arthrotomy into the radiocapitellar joint. Each specimen then underwent valgus loading at 1.75 and 5.25 Nm of torque with the biceps, brachialis, and triceps under axial load in each testing condition. RESULTS: The average valgus laxity in the intact elbow at 90° was 3.7° ± 0.6° at the 5.25 Nm level of torque, which doubled after transection. The reconstruction group demonstrated less laxity (2.4° ± 0.4°) and reduced valgus angulation of the ulna at 5.25 Nm of torque. The transected UCL condition showed peak contact pressure 67% higher compared with the native ligament group at 5.25 Nm of torque. The reconstructed group increased peak articular cartilage pressures by 33% from the native ligament. At 5.25 Nm of torque for the 90° flexion phase, the transected UCL condition showed an average contact pressure of 84% greater than that of the native ligament group. Reconstruction of the UCL restored average articular pressures to within 20% of intact values at 90°. CONCLUSION: UCL injury increases radiocapitellar contact pressures and reduces resistance of the elbow to valgus loading. Contact pressures and valgus laxity can be improved with UCL reconstruction. DISCUSSION: Taken as a whole, the peak pressure data indicate that the reconstruction restores valgus stability and lateral contact pressures to nearly normal levels under the conditions tested. Because the 90 position is the clinically significant position, these laboratory data support the clinical success of the docking procedure.

Progression of Hamate Hook Stress Reactions in Elite Baseball Players.

BACKGROUND: Hamate hook fractures can occur as a result of repetitive contact with the knob of the bat used in the sport of baseball. Hamate hook excision has resulted in excellent outcomes and return to sport (RTS) in elite baseball players. The ideal treatment for hamate stress response before the development of a fracture line is unknown. PURPOSE: To report the outcomes of elite baseball players with hamate bone edema. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We reviewed the medical records of all elite baseball players with hamate bone edema consistent with a stress response at 2 institutions. Players were eligible for inclusion if they played collegiate or professional baseball at the time of initial injury, had magnetic resonance imaging (MRI) showing hamate bone edema, and had no radiographic evidence of acute fracture lines at initial presentation. RESULTS: A total of 4 players with a mean age of 22.8 years were included. All injuries occurred in the nondominant hand. All athletes had normal initial wrist radiographs and MRI showing hamate edema but no fracture line. Patients returned to play as tolerated and developed an acute injury at an average of 25.8 days (range, 10-56 days) from the initial presentation. Repeat radiographs demonstrated acute hamate hook fractures in all 4 (100%) athletes. All 4 athletes underwent hamate hook excision. There were no postoperative complications. All athletes returned to sport at their previous level of competition at a mean of 5.3 weeks (range, 3.6-7.3 weeks). CONCLUSION: There is a high rate of hamate bone edema progression to acute hamate hook fracture in elite baseball players, with 100% RTS at preinjury level after hamate hook excision. We therefore recommend against prolonged rest. Continuation of play with hamate bone edema followed by hamate hook excision for acute fracture limits the time missed and obtains a faster RTS in elite baseball players.

Omegawave: an emerging technology and application in professional baseball pitchers.

BACKGROUND: Wearable technology has become increasingly popular in the recent years. Omegawave is a wearable technology used by multiple professional sports organizations. The purpose of this investigation was to determine if: 1) Omegawave readiness correlates with in-game performance for professional baseball pitchers; 2) Omegawave ready pitchers have better in-game statistics than pitchers who are not Omegawave ready; 3) Omegawave readiness predicts a day when pitchers are most ready to return to the mound. METHODS: A prospective double-blinded study was performed from May 26, 2016 to September 10, 2016. Nineteen minor league pitchers (22.2±1.9 years of age; seven left- and 12 right-handed; nine starting and 10 relief pitchers) were analyzed. RESULTS: For relief pitchers, there was a weak negative correlation with opponent slugging percentage (SLG) (Rs =-0.30; P=0.015) and a weak positive correlation with strikeouts per nine innings (K/9) (Rs =0.30; P=0.016). Starting pitchers who were Omegawave ready did not pitch better (P>0.05) than starting pitchers who were not Omegawave ready. Relief pitchers who were Omegawave ready had lower (P<0.05) earned run average (ERA), SLG, and opponent on base plus slugging percentage (OOPS) than relief pitchers who were not Omegawave ready. CONCLUSIONS: Relief pitchers who were Omegawave ready had lower ERA, SLG, and OOPS than relief pitchers who were not Omegawave ready. This study was unable to identify a day in which pitchers may be most ready to pitch after an appearance.

Performance and Return to Sport After Thumb Ulnar Collateral Ligament Surgery in National Football League Players.

Background: Acute ruptures of the ulnar collateral ligament (UCL) of the thumb are common injuries in sports. Surgical repair of complete tears has yielded excellent results in elite athletes. Methods: National Football League (NFL) players who underwent thumb UCL surgery and matched controls were identified. Demographic and performance data were collected. Performance scores were calculated using a standardized scoring system. Return to sport (RTS) in the NFL was defined as playing in at least 1 NFL game after thumb UCL surgery. Comparisons between case and control groups and preoperative and postoperative time points were made using paired-samples Student t tests. Results: Twenty-three players were identified (mean age: 28.8 ± 3.4 years and mean experience in the NFL: 5.9 ± 3.4 years). Twenty-two players (95.7%) were able to return to sport in the NFL at an average of 132.2 ± 126.1 days. The overall 1-year NFL career survival rate of players undergoing thumb UCL surgery was 87.0%. There was not a statistically significant decrease in games per season and career length for any position following surgery. No positions had a significant difference in postoperative performance when compared with preoperative performance, and there was no significant performance difference postoperatively when compared with matched controls. Conclusions: There is a high rate of RTS in the NFL following thumb UCL surgery. Players who underwent thumb UCL surgery played in a similar number of games per season and had similar career lengths in the NFL as controls. No position group had any significant postoperative performance score differences when compared with postindex matched controls.

Performance and Return to Sport After Hip Arthroscopic Surgery in Major League Baseball Players.

BACKGROUND: Femoroacetabular impingement (FAI) is a common cause of hip pain that may lead to decreased performance in Major League Baseball (MLB) players. PURPOSE: To determine the (1) return-to-sport (RTS) rate in MLB players after hip arthroscopic surgery for FAI; (2) postoperative career length, innings pitched (IP) (pitchers), and plate appearances (PA) (position players); (3) preoperative and postoperative performance; and (4) postoperative performance compared with control players matched by position, age, years of experience, and performance. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: MLB athletes who underwent hip arthroscopic surgery for FAI and matched controls were identified. Demographic and performance data were collected. RTS was defined as playing in at least 1 MLB game after surgery. Continuous variables of each group were compared using a 2-tailed paired-samples Student t test for normally distributed data. The chi-square test was used to analyze categorical data. The Bonferroni correction was used to control for multiple comparisons, with statistical significance defined by a P value of ≤.007. RESULTS: A total of 50 players (57 surgeries) were analyzed (mean age, 30.4 ± 3.9 years; mean MLB experience at the time of surgery, 7.0 ± 4.6 years). Pitchers (31 surgeries; 54.4%) represented the largest proportion of players analyzed. Of these players, 42 (47 surgeries; 82.5%) were able to RTS at a mean of 8.3 ± 4.1 months. The overall 1-year MLB career survival rate of players undergoing FAI surgery was 78.9%. Players in the control group were in MLB a similar number of years (4.0 ± 2.9 years) to players who underwent surgery (3.3 ± 2.4 years) (P > .007). There was no significant decrease in IP or PA per season after surgery (P > .007). There was no significant difference in performance for pitchers and nonpitchers compared with matched controls after surgery (P > .007). CONCLUSION: The RTS rate for MLB athletes after hip arthroscopic surgery for FAI was high. There were similar IP, PA, and career lengths postoperatively compared with preoperatively and with matched controls. There was no significant difference in performance for pitchers and nonpitchers compared with matched controls after surgery.