The Principles of Knee Joint Preservation.

The 3 primary factors involved with preservation of the knee joint include joint alignment, meniscal status, and ligament stability (in particular that of the anterior cruciate ligament [ACL]). These factors are interdependent and result in knee joint homeostasis when all factors are stable. When a deficiency exists in one of the factors, it will affect the others. For example, the ACL and posterior horn of the medial meniscus both act as restraints to anterior tibial translation. Thus, medial meniscal deficiency increases the risk for failure of ACL reconstruction, and chronic ACL insufficiency increases the risk for medial meniscus tears. Furthermore, all 3 of the factors of joint preservation have an impact on the articular cartilage status of the knee joint. Studies have shown that cartilage-preservation procedures do not result in optimal outcomes if there is joint malalignment, meniscal deficiency, or ligament deficiency. When evaluating patients with knee cartilage pathology, surgeons should be aware of the various factors involved in knee joint preservation and, if surgery is indicated, all factors should be addressed in order to support a successful result.

Patients With Knee Osteoarthritis Who Receive Platelet-Rich Plasma or Bone Marrow Aspirate Concentrate Injections Have Better Outcomes Than Patients Who Receive Hyaluronic Acid: Systematic Review and Meta-analysis.

PURPOSE: To systematically review the literature to compare the efficacy and safety of platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and hyaluronic acid (HA) injections for the treatment of knee osteoarthritis (OA). METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify Level I studies that compared the clinical efficacy of at least 2 of the following 3 injection therapies: PRP, BMAC, and HA for knee OA. The search phrase used was knee AND osteoarthritis AND randomized AND ("platelet rich plasma" OR "bone marrow aspirate" OR "hyaluronic acid"). Patients were primarily assessed based on patient-reported outcome scores (PROs) including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and Subjective International Knee Documentation Committee (IKDC) score. RESULTS: Twenty-seven studies (all Level I) met inclusion criteria, including 1,042 patients undergoing intra-articular injection(s) with PRP (mean age 57.7 years, mean follow-up 13.5 months), 226 patients with BMAC (mean age 57.0 years, mean follow-up 17.5 months), and 1,128 patients with HA (mean age 59.0 years, mean follow-up 14.4 months). Nonnetwork meta-analyses demonstrated significantly better postinjection WOMAC (P < .001), VAS (P < .01), and Subjective IKDC scores (P < .001) in patients who received PRP compared with patients who received HA. Similarly, network meta-analyses demonstrated significantly better postinjection WOMAC (P < .001), VAS (P = .03), and Subjective IKDC (P < .001) scores in patients who received BMAC compared with patients who received HA. There were no significant differences in postinjection outcome scores when comparing PRP with BMAC. CONCLUSIONS: Patients undergoing treatment for knee OA with PRP or BMAC can be expected to experience improved clinical outcomes when compared with patients who receive HA. LEVEL OF EVIDENCE: Level I, meta-analysis of Level I studies.

Screw Fixation for the Latarjet Procedure May Reduce Risk of Recurrent Instability but Increases Reoperation Rate Compared to Suture-Button Fixation: A Systematic Review.

PURPOSE: To perform a systematic review to compare clinical outcomes, complications, and reoperation rates of patients undergoing the Latarjet procedure with screw vs suture-button fixation. METHODS: A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify clinical studies directly comparing screw vs suture-button fixation for the Latarjet procedure. The search terms used were shoulder screw suture button. Patients were evaluated based on reoperation rate, complication rate, recurrent instability, radiologic outcomes, and patient-reported outcomes. Graft and screw position were assessed via computed tomography. RESULTS: Seven studies (1 Level II, 6 Level III) met inclusion criteria, with 845 patients undergoing the Latarjet procedure with screw fixation (screw group) and 279 patients with suture-button fixation (suture-button group). Mean patient age ranged from 21.2 to 29.6 years. Mean follow-up time ranged from 6.0 to 40.8 months. The recurrent instability rate ranged from 0% to 2.5% in the screw group and 0% to 8.3% in the suture-button group. The reoperation rate ranged from 0% to 7.7% in the screw group compared to 0% to 1.9% in the suture-button group. One study reported significantly lower visual analog scale pain scores in the suture-button group compared with the screw group (1.5 vs 1.2, P = .003). No other studies reported significant differences in any patient-reported outcomes. There was no significant difference in horizontal or vertical graft position, graft union rate, or complication rate between groups in any study. CONCLUSIONS: The Latarjet procedure with screw fixation may result in a lower risk of recurrent instability compared to suture-button fixation, although screw fixation may also have a higher reoperation rate due to hardware-related complications. LEVEL OF EVIDENCE: Level III, systematic review of Level II to III studies.

Rotator cuff training with upper extremity blood flow restriction produces favorable adaptations in division IA collegiate pitchers: a randomized trial.

BACKGROUND: Recent evidence indicates that combined upper extremity blood flow restriction (BFR, applied distally to the shoulder) and low-load resistance exercise (LIX) augments clinically meaningful responses in shoulder region tissues proximal to the occlusion site. The purpose of this investigation was to determine the efficacy of BFR-LIX for the shoulder when added to standard offseason training in Division IA collegiate baseball pitchers. We hypothesized that BFR-LIX would augment training-induced increases in shoulder-region lean mass, rotator cuff strength, and endurance. As secondary outcomes, we sought to explore the impact of BFR-LIX rotator cuff training on pitching mechanics. METHODS: Twenty-eight collegiate baseball pitchers were randomized into 2 groups (BFRN = 15 and non-BFR [NOBFR]N = 13) that, in conjunction with offseason training, performed 8 weeks of shoulder LIX (Throwing arm only; 2/week, 4 sets [30/15/15/fatigue], 20% isometric max) using 4 exercises (cable external and internal rotation [ER/IR], dumbbell scaption, and side-lying dumbbell ER). The BFR group also trained with an automated tourniquet on the proximal arm (50% occlusion). Regional lean mass (dual-energy x-ray absorptiometry), rotator cuff strength (dynamometry: IR 0 & 90, ° ER 0 & 90, ° Scaption, Flexion), and fastball biomechanics were assessed pre and post-training. Achievable workload (sets × reps × resistance) was also recorded. An ANCOVA (covaried on baseline measures) repeated on training timepoint was used to detect within-group and between-group differences in outcome measures (α = 0.05). For significant pairwise comparisons, effect size (ES) was calculated using a Cohen's d statistic and interpreted as: 0-0.1, negligible; 0.1-0.3, small; 0.3-0.5, moderate; 0.5-0.7, large; >0.7, and very large (VL). RESULTS: Following training, the BFR group experienced greater increases in shoulder-region lean mass (BFR: ↑ 227 ± 60g, NOBFR: ↑ 75 ± 37g, P = .018, ES = 1.0 VL) and isometric strength for IR 90 ° (↑ 2.4 ± 2.3 kg, P = .041, ES = 0.9VL). The NOBFR group experienced decreased shoulder flexion ↓ 1.6 ± 0.8 kg, P = .007, ES = 1.4VL) and IR at 0 ° ↓ 2.9 ± 1.5 kg, P = .004, ES = 1.1VL). The BFR group had a greater increase in achievable workload for the scaption exercise (BFR: ↑ 190 ± 3.2 kg, NOBFR: ↑ 90 ± 3.3 kg, P = .005, ES = 0.8VL). Only the NOBFR group was observed to experience changes in pitching mechanics following training with increased shoulder external rotation at lead foot contact (↑ 9.0° ± 7.9, P = .028, ES = 0.8VL) as well as reduced forward ↓ 3.6° ± 2.1, P = .001, ES = 1.2VL) and lateral ↓ 4.6° ± 3.4, P = .007, ES = 1.0VL) trunk tilt at ball release. CONCLUSION: BFR-LIX rotator cuff training performed in conjunction with a collegiate offseason program augments increases in shoulder lean mass as well as muscular endurance while maintaining rotator cuff strength and possibly pitching mechanics in a manner that may contribute to favorable outcomes and injury prevention in baseball pitching athletes.

Third-Generation Autologous Chondrocyte Implantation (Cells Cultured Within Collagen Membrane) Is Superior to Microfracture for Focal Chondral Defects of the Knee Joint: Systematic Review and Meta-analysis.

PURPOSE: To systematically review randomized controlled trials to compare clinical outcomes of microfracture (MFx) versus third-generation autologous chondrocyte implantation (ACI) for the treatment of focal chondral defects (FCDs) of the knee joint. METHODS: A systematic review was performed by searching PubMed, Cochrane Library, and EMBASE to locate randomized controlled trials comparing minimum 2-year clinical outcomes of patients undergoing MFx versus third-generation ACI for FCDs of the knee joint. The search terms used were: "knee" AND "microfracture" AND "autologous chondrocyte" AND "randomized." Patients were evaluated based on treatment failure rates, magnetic resonance imaging, International Cartilage Repair Society scores, and patient-reported outcome scores (Lysholm, Tegner, Knee Injury and Osteoarthritis Outcome Score, modified Cincinnati Knee Rating System, 12-item Short Form Health Survey Physical and Mental, and the EuroQol 5 Dimensions Visual Analog Scale score). RESULTS: Six studies (5 Level I, 1 Level II) met inclusion criteria, including a total of 238 patients undergoing MFx and 274 undergoing ACI. Two studies had an overlapping cohort of patients and therefore the study with longer follow-up was used in all analyses. The average follow-up among patients ranged from 2.0 years to 6.0 years. Average lesion size ranged from 1.8 cm2 to 5.0 cm2. Treatment failure ranged from 0% to 1.8% in the ACI group and 2.5% to 8.3% in the MFx group. In 4 studies, ACI patients demonstrated significantly greater improvement in multiple Knee Injury and Osteoarthritis Outcome Score subscores compared with MFx. In 2 studies, patients who received ACI demonstrated significantly greater improvement in the Tegner score compared to MFx, and 1 study showed significantly greater improvement in the Lysholm and ICRS scores for ACI compared with MFx. CONCLUSIONS: At short-term follow-up, third-generation ACI demonstrates a lower failure rate and greater improvement in patient-reported outcomes compared with MFx for FCDs of the knee joint. LEVEL OF EVIDENCE: II, systematic review of Levels I-II studies.

Sex-Related Hip Strength Measures Among Professional Soccer Players.

ABSTRACT: Hedt, CA, Pearson, JM, Lambert, BS, McCulloch, PC, and Harris, JD. Sex-related hip strength measures among professional soccer players. J Strength Cond Res 35(7): 1992-1999, 2021-Lower-extremity musculoskeletal injuries in soccer are common among sexes. However, it remains unknown whether differences between sexes exist with regard to absolute or relative hip strength and how these differences may relate to injury. In the current study, we performed a retrospective cross-sectional analysis of pre-season data from male (♂n = 21) and female (♀n = 19) professional United States soccer organizations. Two years of pre-season data were collected for peak strength of lower extremity and hip musculature (no duplicates used). A 2 × 2 multivariate analysis of variance was used to detect differences in hip strength between sexes and dominant compared with nondominant legs. For all significant multivariate effects indicated by Wilks lambda and follow-up univariate analysis, a Tukey's post hoc test was used for pairwise univariate comparisons. A 2-tailed independent-samples T-test was used for comparison of height, body mass, body mass index (BMI), mean leg length, and strength ratios between dominant and nondominant limbs between sexes. Type I error was set at α = 0.05 for all analyses. Height (♂183.1 ± 6.8 cm, ♀170.0 ± 5.5 cm), body mass (♂79.0 ± 8.7 kg, ♀65.1 ± 5.6 kg), BMI (♂23.5 ± 1.3 kg·m-2, ♀22.5 ± 1.4 kg·m-2), and mean leg length (♂95.5 ± 4.34 cm, ♀ 88.3 ± 3.24 cm) differed between groups (p < 0.05). Sex differences (p < 0.05) were also found for hip abduction (dominant ♂19.5 ± 3.6 kg, ♀17.3 ± 2.2 kg; nondominant ♂18.5 ± 3.7 kg, ♀16.0 ± 2.3 kg), adduction (dominant ♂19.8 ± 3.0 kg, ♀16.7 ± 2.3 kg; nondominant ♂20.1 ± 2.9 kg, ♀17.6 ± 2.9 kg), external rotation (dominant ♂21.7 ± 3.4 kg, ♀17.7 ± 2.4 kg; nondominant ♂21.6 ± 3.9 kg, ♀16.8 ± 2.1 kg), and dominant hamstring strength (♂27.9 ± 6.5 kg, ♀23.0 ± 4.9 kg). The ratio of hip internal to external rotation strength differed in the nondominant leg (♂1.1 ± 0.2, ♀0.9 ± 0.2, p < 0.05). No significant differences were found between males and females when measures were normalized to body mass. These findings provide baseline pre-season normative data for professional soccer athletes and indicate that strength differences can be expected among different sexes, but are attenuated with attention to body mass. Further research should indicate how pre-season strength measures relate to injury.

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.

Shear-wave elastography of the ulnar collateral ligament of the elbow in healthy volunteers: a pilot study.

OBJECTIVE: To estimate the intra-observer repeatability of shear wave elastography in the UCL of the elbow, and to compare shear wave velocities between dominant and non-dominant arms. MATERIALS AND METHODS: Twenty elbows in ten healthy volunteers were evaluated [five males, five females; mean age, 31.8 ± 10.3 years]. Shear wave velocity was measured on three separate days during the span of 1 week utilizing a linear 18-MHz transducer. Elastograms were obtained until ten ROIs were drawn, not drawing more than two ROIs on any elastogram. Elastograms were considered diagnostic if any portion of the UCL was colored in and free of boundary artifacts. Median velocity and interquartile range were recorded. A result was considered reliable if the IQR/median ratio of the ten measurements was < 0.3. RESULTS: IQR/median was < 0.3 in 88% of sessions, although in 28% of sessions fewer than 60% of elastograms were diagnostic. The ICC was 0.05 (95% CI; - 0.18-0.36; poor). Repeatability coefficient (95% limits of agreement) was 1.95 m/s (95% CI; 1.61-2.37 m/s). Mean velocity in dominant arms was 5.14 ± 0.53 m/s and 5.24 ± 0.39 m/s in non-dominant (p = 0.558). CONCLUSIONS: Mean shear wave velocity was similar between dominant and non-dominant arms. Although repeatability was poor as assessed by ICC, the repeatability coefficient may be a more useful indicator of clinical utility once shear wave velocities in diseased ligaments are explored. Future studies should therefore evaluate velocities in diseased ligaments and develop techniques to improve elastogram quality.

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.

The Utilization of Interval Throwing Programs in the Physical Therapy Setting: A Cross-Sectional Survey.

Context: Interval throwing programs (ITPs) have long been used in the physical therapy setting to aid in the safe and efficacious return to sport for an overhead athlete. However, the overall utilization and variation of ITPs are unknown in the physical therapy setting leading to potential inconsistencies in treatment paradigms. Objective: To determine if differences in practice patterns exist among active physical therapists of various experience levels with regard to years of experience and advanced certifications. Design: Cross-sectional survey study. Participants: A total of 133 licensed physical therapists consented to participate in an online-based survey. Experience groups were delineated based on years of practice (0-1, 1-5, 6-15, and 15+) and possession of advanced certification. Main Outcome Measures: For ranking-based data, a generalized linear mixed model was repeated across criteria response with a Bonferroni post hoc adjustment for pairwise comparisons made within and between groups (α < .05). For degree-based questions, chi-square analysis was used to compare response frequencies for options provided within each question. Results: A 76.7% response rate was achieved with 102 out of the 133 consenting individuals completed the survey. Significant differences (P < .05) were found with responses to both ranking-based and degree-based questions. However, across all groups, physical therapists agreed that throwing mechanics and customized ITP implementation were important for a successful return to throwing. Conclusions: There are inherent differences in ITP prescription among physical therapists with dissimilar experience levels. The possession of advanced certifications and years of practice seem to play a role in how interval programs are prescribed to overhead-throwing athletes. This study helps to identify differences in current physical therapy approaches toward the later stages of rehabilitation for throwing athletes. Further research should identify areas of improvement in physical therapist education as well as appropriate ITP prescription parameters to optimize care and treatment for this patient population.

Are Self-Reported Medication Allergies Associated With Worse Hip Outcome Scores Prior to Hip Arthroscopy?

PURPOSE: To determine if there are significant differences in preoperative patient-reported outcome (PRO) scores in patients with and without self-reported medication allergies undergoing hip arthroscopy. METHODS: Consecutive subjects undergoing hip arthroscopy for femoroacetabular impingement (FAI) syndrome by a single surgeon were retrospectively reviewed. PROs were collected within 6 weeks of the date of surgery. PROs included International Hip Outcome Tool (iHOT-12), Hip Outcome Score (HOS), and Short-Form (SF-12) scores. Allergies to medications were self-reported preoperatively within 6 weeks of the date of surgery. Patient demographics were recorded. Bivariate correlations and multivariate regression models were calculated to identify associations with baseline hip outcome scores. RESULTS: Two hundred twelve subjects were analyzed (56% female, mean age 35.1 ± 13.2 years). Seventy-two subjects (34%) self-reported allergies (range 1-10; 41 subjects had 1 allergy; 14 subjects had 2; 8 subjects had 3; 2 subjects had 4; 7 subjects had 5 or more). The most commonly reported allergies included penicillin (18), sulfa (13), and codeine (11). Female gender was significantly correlated with number of allergies (Pearson correlation coefficient, 0.188; P < .001). SF-12 Mental Component Score (MCS) was significantly correlated with HOS-ADL (Pearson correlation coefficient, 0.389; P < .001), HOS-SSS (Pearson correlation coefficient, 0.251; P < .001), and iHOT-12 (Pearson correlation coefficient, 0.385; P < .001). There was no significant correlation between number of allergies and all hip PROs. In all multivariate models, the SF-12 MCS had the strongest association with HOS-ADL, HOS-SSS, and iHOT-12 (P < .001 for all). Allergies were not significantly associated with any hip PROs. CONCLUSIONS: In patients undergoing hip arthroscopy for FAI syndrome, self-reported medication allergies are not significantly associated with preoperative patient-reported hip outcome scores. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.

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.

Is digital photography an accurate and precise method for measuring range of motion of the shoulder and elbow?

BACKGROUND: Accurate measurements of shoulder and elbow motion are required for the management of musculoskeletal pathology. The purpose of this investigation was to compare three techniques for measuring motion. The authors hypothesized that digital photography would be equivalent in accuracy and show higher precision compared to the other two techniques. METHODS: Using infrared motion capture analysis as the reference standard, shoulder flexion/abduction/internal rotation/external rotation and elbow flexion/extension were measured using visual estimation, goniometry, and digital photography on 10 fresh frozen cadavers. These measurements were performed by three physical therapists and three orthopaedic surgeons. Accuracy was defined by the difference from the reference standard (motion capture analysis), while precision was defined by the proportion of measurements within the authors' definition of clinical significance (10° for all motions except for elbow extension where 5° was used). Analysis of variance (ANOVA), t-tests, and chi-squared tests were used. RESULTS: Although statistically significant differences were found in measurement accuracy between the three techniques, none of these differences met the authors' definition of clinical significance. Precision of the measurements was significantly higher for both digital photography (shoulder abduction [93% vs. 74%, p < 0.001], shoulder internal rotation [97% vs. 83%, p = 0.001], and elbow flexion [93% vs. 65%, p < 0.001]) and goniometry (shoulder abduction [92% vs. 74%, p < 0.001] and shoulder internal rotation [94% vs. 83%, p = 0.008]) than visual estimation. Digital photography was more precise than goniometry for measurements of elbow flexion only [93% vs. 76%, p < 0.001]. CONCLUSIONS: There was no clinically significant difference in measurement accuracy between the three techniques for shoulder and elbow motion. Digital photography showed higher measurement precision compared to visual estimation for shoulder abduction, shoulder internal rotation, and elbow flexion. However, digital photography was only more precise than goniometry for measurements of elbow flexion. Overall digital photography shows equivalent accuracy to visual estimation and goniometry, but with higher precision than visual estimation.

Brake Reaction Time After Hip Arthroscopy for Femoroacetabular Impingement and Labral Tear.

PURPOSE: To determine if a difference exists in brake reaction time (BRT) before and after hip arthroscopy for femoroacetabular impingement (FAI) and labral tear compared with age- and gender-matched controls. METHODS: Consecutive adult subjects undergoing primary hip arthroscopy were eligible for this prospective investigation. Individuals with symptomatic FAI and labral tear that underwent hip arthroscopy with minimum 8 weeks follow-up were included. BRT was measured using the RT-2S reaction time tester a maximum of 6 weeks preoperatively and every 2 weeks postoperatively for 8 weeks. Sit-to-stand test (STST) was measured at each BRT testing session. An age- and gender-matched control group without hip or lower extremity symptoms were selected and completed both BRT and STST. Continuous pre- and postoperative BRT values were compared with Mann-Whitney and analyses of variance. Association of BRT and STST tests was performed with Spearman correlation. An a priori sample size calculation determined that minimally 18 subjects per group (surgery group vs control group) were necessary to detect, with 80% power (difference of 0.2 seconds in BRT). RESULTS: Nineteen subjects (age 37.1 ± 12.7 years, 10 women, 11 right hip) were analyzed. All subjects underwent arthroscopic labral repair and FAI correction. There was no difference between preoperative (604 ± 148 milliseconds [ms]) and postoperative (608 ms 2 weeks; 566 ms 4 weeks; 559 ms 6 weeks; 595 ms 8 weeks) BRT. There was no difference between controls and subjects at any time point. There was a strong negative correlation between BRT and STST preoperatively and at 4 and 6 weeks postoperatively and a moderate negative correlation at 2 weeks postoperatively. CONCLUSIONS: After hip arthroscopy for FAI and labral tear, BRT is not different from preoperative values or that of controls. In addition, BRT had a significant correlation with STST in the first 6 weeks after surgery. LEVEL OF EVIDENCE: Level II, diagnostic, prospective.

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.