Subacromial balloon spacer massive rotator cuff tear treatment systematic review and meta-analysis: Patient selection and physical therapy may be keys to outcome success.

PURPOSE: Subacromial balloon spacer implantation (SBSI) efficacy for massive rotator cuff tear treatment was evaluated based on perceived shoulder function, active shoulder mobility, pain, complications and research study methodological quality. The purpose was to better discern the efficacy of this device from both surgical and rehabilitative perspectives to improve patient outcomes. METHODS: PubMed, EMBASE and Cochrane Library databases were searched (1 January 2010 to 1 June 2024) using 'balloon spacer', 'subacromial spacer', 'subacromial balloon spacer', 'shoulder spacer' and 'inspace' terms. Pre-surgery (baseline), 12-month (12-m) and 24-month (24-m) post-SBSI mean changes were compared using one-way ANOVA and Scheffe post hoc tests, and comparative study effect sizes were calculated (p ≤ 0.05). RESULTS: This review consists of 27 studies with 894 patients (67.8 ± 5 years of age) and 29.4 ± 17-month follow-up. Modified Coleman Methodology Scores (MCMS) revealed fair overall quality (mean = 61.4 ± 11). Constant-Murley scores improved from 34.8 ± 6 (baseline), to 64.2 ± 9 (12-m) and 67.9 ± 8 (24-m) (12-m, 24-m > baseline, p < 0.001). ASES scores improved from 35.1 ± 14 (baseline), to 83.3 ± 7 (12-m) and 81.8 ± 5 (24-m)(12-m, 24-m > baseline, p < 0.001). VAS pain scores improved from 6.6 ± 1 (baseline), to 2.6 ± 1 (12-m) and 2.0 ± 1 (24-m) (12-m, 24-m < baseline, p < 0.001). Flexion increased from 108.5 ± 25° (baseline), to 128.5 ± 30° (12-m) and 151.2 ± 14° (24-m) (24-m > 12-m, baseline, p = 0.01). Abduction increased from 97.7 ± 24° (baseline) to 116.3 ± 23° (12-m) and 142.3 ± 15° (24-m) (24-m > 12-m, baseline, p = 0.02). External rotation (ER) in adduction changed from 33.1 ± 7° (baseline) to 32.5 ± 4° (12-m) and 53.9 ± 9° (24-m)(24-m > 12-m, baseline, p = 0.01). ER at 90° abduction increased from 56.3 ± 3° (baseline) to 83.5 ± 5° (12-m) and 77.1 ± 4° (24-m) (24-m, 12-m > baseline, p = 0.01). Comparison studies, however, displayed insignificant results with small effect sizes. CONCLUSION: Despite overall fair MCMS scores, at 24-m post-SBSI, shoulder function improved and pain decreased. More rigorous comparative studies, however, revealed insignificant findings. Patients with the potential to re-establish the essential glenohumeral joint force couple that depresses the humeral head on the glenoid fossa and who comply with physical therapy may be more likely to achieve success following SBSI. LEVEL OF EVIDENCE: Level IV.

Adolescent Athletes with Stronger Athletic Identity Perceptions Have Weaker Fear Avoidance Perceptions During Musculoskeletal Injury Rehabilitation Return to Sports Preparation.

BACKGROUND: Adolescent athletes who sustain a musculoskeletal sports injury are at high re-injury risk. This prospective study evaluated athletic identity perception and fear avoidance perception relationships during the return to sport preparation phase of musculoskeletal injury rehabilitation. METHODS: From 140 consecutive physical therapy outpatients, 50 (26 females, 24 males) adolescent athletes (mean age 16.8, range 14 to 22 y) completed the 7-item Athletic Identity Measurement Scale (AIMS), the 10-item Athletic Fear Avoidance Questionnaire (AFAQ), and the AFAQ with 2 additional movement-related fear and pain questions (AFAQ+). Correlational analysis was performed of overall AIMS and AIMS subscale scores (social identity, exclusivity, negative affectivity), with AFAQ and AFAQ+ scores ( P ≤0.05). RESULTS: Adolescent athletes were receiving treatment for musculoskeletal injuries sustained during soccer (n=10), lacrosse (n=7), baseball (n=6), basketball (n=5), volleyball (n=5), track or cross country (n=4), American football (n=4), field hockey or ice hockey (n=3), softball (n=2), tennis (n=2), and gymnastics (n=2). Lower extremity conditions included anterior cruciate ligament reconstruction (n=23) or other lower extremity conditions (n=17). Upper extremity conditions included shoulder dislocation or labral repair (n=6), elbow sprain or fracture (n=3), and clavicle fracture (n=1). The AIMS score displayed moderate inverse relationships with AFAQ ( r =-0.40, P =0.008) and AFAQ+ ( r =-0.41, P <0.004) scores. The "social identity" AIMS subscale score displayed a moderate inverse relationship with AFAQ ( r =- 0.48, P <0.001) and AFAQ+ ( r =-0.46, P =0.001) scores. The "exclusivity" AIMS subscale score displayed moderate inverse relationships with AFAQ ( r =-0.40, P =0.005) and AFAQ+ ( r =-0.46, P =0.001) scores. The "negative affectivity" subscale did not display significant relationships with AFAQ or AFAQ+ scores. Subject age displayed moderate inverse relationships with the AIMS "social identity" ( r =-0.56, P <0.001) and "exclusivity" ( r =-0.42, P =0.004) subscale scores and weak direct relationships with AFAQ (r=0.30, P =0.04) and AFAQ+ (r=0.32, P =0.02) scores. CONCLUSION: Adolescent athletes with stronger athletic identity perceptions during the return to the sports preparation phase of musculoskeletal injury rehabilitation had weaker fear avoidance perceptions. As age increased from early to late adolescence, athletic identity perceptions became weaker, and fear avoidance perceptions became stronger. To decrease re-injury rates, early identification and surveillance of injured adolescent athletes with stronger, more exclusive athletic identity perceptions and weaker fear avoidance perceptions may influence rehabilitation progression and return to play decisions. LEVEL OF EVIDENCE: Level-II, prospective cohort, correlational study.

A two-year comparison of reverse total shoulder arthroplasty mini-humeral tray and augmented mini-glenoid baseplate implants vs. standard implants.

BACKGROUND: Patients who undergo reverse total shoulder arthroplasty (RTSA) are getting younger with greater function expectations. This retrospective, longitudinal study of prospectively collected data compared perceived shoulder function and strength, active shoulder mobility, radiographic evidence of scapular notching, and implant survival over the initial 2-years post-RTSA among patient groups who received either standard central fixation point liner and glenoid baseplate implants, or lower size profile mini-humeral tray with offset trunnion options and mini-augmented glenoid baseplate implants. MATERIALS AND METHODS: Patients who underwent primary RTSA using standard central fixation point liner and glenoid baseplate implants (Group 1, n = 180) were compared with patients who underwent primary RTSA using lower size profile mini-humeral tray with offset trunnion options and mini-augmented glenoid baseplate implants (Group 2, n = 53) for active shoulder mobility, American Shoulder and Elbow Surgeons (ASES) score, perceived ability to lift 10 lbs (4.5 kg) overhead, radiographic evidence of scapular notching, and implant survival. Data was collected pre-surgery, 6-weeks, 6-months, 1-year, and 2-years post-RTSA (p ≤ 0.05). RESULTS: More Group 2 patients had more complex B or C Walch glenoid morphology, while Group 1 had more A1 or A2 types (p ≤ 0.001). Group 2 had greater active shoulder flexion at 6-months, 1-year, and 2-years (p ≤ 0.018) and external rotation (in adduction) at 6-months and 2-years (p ≤ 0.004) compared to Group 1, with higher ASES scores at 6-months and 2-years (p ≤ 0.026) (with small-to-medium effect sizes), and with more patients meeting or exceeding the minimal clinically important difference (MCID) at 2-years (p = 0.045) and patient acceptable symptomatic state (PASS) levels at 6-months, 1-year and 2-years (p ≤ 0.045). Scapular notching was identified in six of 53 (11.3%) Group 2 patients and in 32 of 180 (17.7%) Group 1 patients. Group 1 patients had more grade 2 or greater scapular notching grades compared to Group 2 (p = 0.04). Implant survival was comparable with Group 1 = eight of 180 (4.4%) and Group 2 = 1 of 53 (1.9%) of patients requiring removal for 95.6% and 98.1% implant survival, respectively. CONCLUSION: Limited scapular notching and excellent implant survival was observed in both groups. Despite including individuals with more complex glenoid deficiency, patients receiving the lower size profile implants generally displayed better active shoulder mobility and perceived shoulder function compared to those who received standard implants. These patients also more frequently met or exceeded the MCID by 2-years post-RTSA and PASS levels by 6-months, 1-year, and 2-years post-RTSA, with lower scapular notching grades. LEVEL OF EVIDENCE: Retrospective comparative study.

Mini-augmented glenoid baseplate and mini-humeral tray reverse total shoulder arthroplasty implant comparisons: two-year clinical outcomes.

BACKGROUND: Augmented glenoid baseplate and offset humeral tray reverse total shoulder arthroplasty (RTSA) implants may decrease the mechanical impingement that creates scapular notching and improve shoulder function. This study evaluated the clinical efficacy of three different RTSA glenoid baseplate and offset humeral tray combinations for patient-reported shoulder function, pain and instability, radiographic imaging evidence of glenoid baseplate or humeral stem subsidence and migration, bony changes associated with implant loosening, and scapular notching over the initial 2 years post-RTSA. Primary outcomes included active shoulder mobility, perceived function, pain, instability, scapular notching, and implant survival. METHODS: Sixty-seven patients from 6 research sites received one of three different glenoid baseplate and humeral tray combinations. Group 1 (n = 21) received a mini-augmented glenoid baseplate with a standard humeral tray; Group 2 (n = 23) received a standard glenoid baseplate and a mini-humeral tray with 3 trunnion offset options; Group 3 (n = 23) received both a mini-augmented glenoid baseplate and a mini-humeral tray with 3 trunnion offset options. Subjects underwent radiologic evaluation, completed the ASES scale, the EQ-5D-5L quality of life scale, VAS shoulder pain and instability questions, and active shoulder mobility measurements pre-operatively, and 6-weeks, 6-months, 1-2 years post-RTSA. RESULTS: Improved active shoulder mobility, quality of life, perceived function, decreased shoulder pain and instability, excellent implant survival and minimal scapular notching were observed for all groups. Group 3 had better overall active shoulder mobility than the other groups and better perceived function than Group 1. CONCLUSION: The group that received the mini-augmented glenoid baseplate and mini-humeral tray combination had better overall active shoulder flexion, external rotation at 90° abduction, and internal rotation. This group also had better perceived shoulder function compared to the group that received a mini-augmented glenoid baseplate with a standard humeral tray.

Interpositional scaffold anchor rotator cuff footprint tear repair: excellent survival, healing, and early outcomes.

PURPOSE: Shoulder function limitation duration after a full-thickness rotator cuff tendon (RCT) tear may influence post-repair healing and outcomes. A suture anchor was developed to improve footprint repair fixation and healing through biological fluid delivery and scaffold augmentation. The primary multicenter study objective was to evaluate RCT repair failure rate based on 6-month MRI examination, and device survival at 1-year follow-up. The secondary objective was to compare the clinical outcomes of subjects with shorter- and longer-term shoulder function limitation duration. METHODS: Seventy-one subjects (46 men) with moderate-to-large RCT tears (1.5-4 cm), at a median 61 years of age (range = 40-76), participated in this study. Pre-repair RCT tear location/size and 6-month healing status were confirmed by an independent radiologist. Subjects with shorter- (Group 1: 17.8 ± 21 days, n = 37) and longer-term (Group 2: 185.4 ± 89 days, n = 34) shoulder function limitation durations were also compared over 1 year for active mobility, strength, American Shoulder and Elbow Surgeon's Shoulder Score (ASES score), Veterans RAND 12 Item Health Survey (VR-12), and visual analog scale (VAS) pain and instability scores. RESULTS: Three of the 52 subjects [5.8%] who underwent 6-month MRI experienced a re-tear at the original RCT footprint repair site. By the 1-year follow-up, overall anchor survival was 97%. Although Group 2 displayed lower ASES and VR-12 scores pre-repair (ASES = 40.1 ± 17 vs. 47.9 ± 17; VR-12 physical health (PH) = 37.2 ± 9 vs. 41.4 ± 8) (p ≤ 0.048), at 3-month post-RCT repair (ASES = 61.3 ± 19 vs. 71.3 ± 20; VR-12 PH = 40.8 ± 8 vs. 46.8 ± 9) (p ≤ 0.038), and at 6-month post-RCT repair (ASES = 77.4 ± 18 vs. 87.8 ± 13; VR-12 PH = 48.9 ± 11 vs. 54.0 ± 9) (p ≤ 0.045), by 1-year post-RCT repair, groups did not differ (n.s.). Between-groups VR-12 mental health score differences were not evident at any time period (n.s.). Shoulder pain and instability VAS scores also did not differ (n.s.), displaying comparable improvement between groups from pre-RCT repair to 1-year post-RCT repair. Groups had comparable active shoulder mobility and strength recovery at each follow-up (n.s.). CONCLUSION: At 6-month post-RCT repair, only 3/52 of patients [5.8%] had a footprint re-tear, and at 1-year follow-up, overall anchor survival was 97%. Use of this scaffold anchor was associated with excellent early clinical outcomes regardless of shoulder function impairment duration. LEVEL OF EVIDENCE: II.

Reverse total shoulder arthroplasty pain and function: new perspectives from a 10-year multicenter study at the 7-year follow-up.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) can decrease shoulder pain and improve function. However, results reportedly deteriorate as patients approach mid-term follow-up and little is known about how this impacts physical health-related quality of life (PHRQOL) and mental health-related quality of life (MHRQOL). The study hypothesis was that shoulder function, pain, and medication use for pain would influence PHRQOL and MHRQOL. METHODS: This prospective cohort study involving subjects from 6 orthopedic clinics and 12 fellowship-trained surgeons evaluated the influence of RTSA on PHRQOL, MHRQOL, shoulder function, pain, instability, and medication use over the initial 7 years of a 10-year study, and device survivorship and revision rates. Clinical examination, the American Shoulder and Elbow Surgeons (ASES) score, Short Form (SF)-12 PHRQOL and MHRQOL assessments, the single assessment numeric shoulder function evaluation (SANE), visual analog scale (VAS) shoulder pain and instability scores, shoulder pain, medication use for pain, surgery satisfaction, survivorship and revision rate data were collected pre-RTSA, and at 6-week, 6-month, 1-year, 2-year, 3-year, 5-year, and 7-year follow-ups. RESULTS: Two hundred participants (108 female) of 69 ± 8.3 years of age, with gross rotator cuff deficiency (poor tissue quality or impaired dynamic stability) (n = 92), glenohumeral joint osteoarthritis (n = 88), failed primary total shoulder arthroplasty (n = 8), non-united humeral head fracture (n = 6) or 3-4 section comminuted humeral head fracture (n = 6) underwent pre-RTSA evaluation. Device survivorship was 94%. Friedman two-way ANOVA and Wilcoxon test pairwise comparisons revealed that compared to pre-RTSA, median active shoulder flexion (+ 25°) and external rotation (+ 10°) mobility improved by 6 months (p < 0.0001) and remained improved. Shoulder flexion (+ 1 grade), abduction, external rotation (+ 0.5 grade), and internal rotation strength (+ 1 grade) also improved by 6 months (p < 0.0001) and remained improved. ASES (+ 26.8), SANE (+ 17.5) and VAS pain (- 5.7) scores improved by 6 weeks (p < 0.0001) and remained improved, as medication use for shoulder pain decreased (- 24.6%) (p < 0.0001). SF-12 PHRQOL scores improved by 6 months (+ 11.5) and remained improved (p < 0.0001). Significant Spearman Rho correlations were observed between shoulder function (ASES or SANE) and SF-12 PHRQOL (r ≥ 0.52) and MHRQOL (r ≥ 0.20) scores (p < 0.0001) supporting the relationship between shoulder function and quality of life. Trend analysis revealed changing shoulder function, pain, and PHRQOL relationships between 2 and 3 years, and 5 and 7 years post-RTSA (Chi-Square, p < 0.05). CONCLUSION: Excellent device survival and good-to-excellent perceived shoulder function, and PHRQOL improvements were observed. Secondary objectives of improved shoulder mobility, strength, pain and instability were also achieved. In contrast to previous reports, subjects did not display shoulder mobility or perceived function deterioration by the 7-year follow-up. Following chronic pain relief at 6 weeks post-RTSA, subjects appear to balance PHRQOL and shoulder pain relationships at the 6-month and 1-year post-RTSA follow-ups. Careful evaluation at this time may help patients with higher pain levels and lower function expectations reverse these trends, or patients with lower pain levels and higher function expectations to optimize RTSA use and longevity.

Liposomal bupivacaine nerve block provides better pain control post-total shoulder arthroplasty than continuous indwelling catheter.

BACKGROUND: Pain control is essential to successful total shoulder arthroplasty (TSA). MATERIALS AND METHODS: This non-blinded, randomized clinical trial compared shoulder pain, narcotic use, interscalene (IS) block application time, and costs in 76 subjects who were randomly assigned to receive either a single injection IS nerve block of 10 cc (133 mg) liposomal bupivacaine mixed with 10 cc of 0.5% bupivacaine (Group 1), or 20 cc of 0.5% ropivacaine direct injection combined with an indwelling IS nerve block catheter delivering 0.2% ropivacaine at a continual 4 cc/h infusion for the initial 3 post-operative days (Group 2). Surgical time, local anesthesia duration, hospital stay length, morphine milligram equivalents (MME) consumed, worst shoulder pain at 24, 48 and 72 h, and complications were recorded. Patient reported function, pain and activity level surveys were completed before, and 6-week post-TSA (P < 0.05). RESULTS: Group 1 had less pain 24-h (0.72 ± 0.8 vs. 3.4 ± 2.9, p < 0.0001) and 48-h (2.5 ± 2.2 vs. 4.8 ± 2.6, p = 0.005) post-TSA. At 24-h post-TSA, MME consumption was similar (Group 1 = 4.5 ± 6.4 vs. Group 2 = 3.7 ± 3.8, p = 0.54), but was lower for Group 1 at 48 h (0.0 ± 0.0 vs. 0.64 ± 0.99, p = 0.001). Group 2 had longer IS block application time (10.00 ± 4.6 min vs. 4.84 ± 2.7 min, p < 0.0001). Only group 2 had a strong relationship between MME consumption over the first 24-h post-TSA and pain 24-h post-TSA (r = 0.76, p < 0.0001), a moderate relationship with pain 48-h post-TSA (r = 0.59, P = 0.001), and a weak relationship with pain 72-h post-TSA (r = 0.44, P = 0.02). Significant relationships for these variables were not observed for Group 1 (r ≤ 0.30, p ≥ 0.23). Group 1 IS block costs were less/patient than Group 2 ($190.17 vs. $357.12 USD). CONCLUSION: A single shot, liposomal bupivacaine interscalene nerve block provided better post-TSA pain control with less narcotic consumption, less time for administration and less healthcare system cost compared to interscalene nerve block using a continuous indwelling catheter. LEVEL OF EVIDENCE: Level I, Prospective, Randomized.

Editorial Commentary: Time-Zero Biomechanical Shoulder Instability Studies Are Valuable But Limited Because They Do Not Replicate Clinical Dynamics.

Severe anterior shoulder instability with glenoid bone loss can be very difficult to treat. A recent cadaveric, biomechanical, time-zero study compared the stability of Bankart repair with long head of the biceps brachi transfer versus conjoined tendon transfer in the scenario of 20% anteroinferior glenoid bone loss. The result is long head of the biceps tendon transfer in combination with the Bankart repair provided the best overall condition compared to Bankart repair alone, or with a conjoined tendon transfer. However, a limitation is that this does not confirm that this surgical approach would provide sufficient long-term noncontractile shoulder stability to withstand repetitive soft-tissue loading in a dynamic, clinical situation.

History of Ulnar Collateral Ligament Injury and College Pitcher Fastball Profiles: A Retrospective, Observational, Live Pitching Analysis.

PURPOSE: The aim of this study was to retrospectively compare the fastball profiles of pitchers who had previously sustained grade I or II ulnar collateral ligament (UCL) injuries, were rehabilitated, and released back for competition with those of pitchers with no history of elbow injury. METHODS: Eighteen pitchers from the pitching staff of 1 National Collegiate Athletic Association Division III team participated in this study. Group 1 had a history of grade I or II UCL injury (n = 8), and group 2 (n = 10) did not. A computerized pitch tracking device was used to analyze ball movement and pitching mechanics. The hypothesis was that the pitchers with a history of injury (group 1) would display differing fastball velocity-ball movement relationships compared to those without (group 2). RESULTS: The groups had similar heights, weights, pitching experiences, and arm slot positions at ball release. The pitching coach-determined preinjury arm slot position and the postinjury computerized pitch tracking device measurements after return to competition displayed strong agreement (r = 0.83), suggesting comparable pre and postinjury pitching techniques. The groups had comparable glenohumeral joint range of motion and fastball profiles, except that group 1 released the ball at a 2.5 times lesser horizontal distance away from the pitching rubber center. Group 2 also displayed consistently more robust and more frequent fastball movement relationships with velocity, horizontal break, and vertical break than group 1. CONCLUSIONS: Reduced horizontal ball release distances at comparable vertical ball release heights without changes in the arm slot position suggest that pitchers with a history of grade I or II UCL injury have greater contralateral trunk tilt and elbow flexion at ball release. Increased contralateral trunk tilt may occur to increase pitch velocity at the expense of ball movement while placing the pitching elbow in a potentially injurious position. Computerized fastball profile analysis using a computerized pitch tracking device, in conjunction with coach pitching technique observation, and team medical staff clinical examination may help better identify pitchers with an increased risk of UCL injury. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Distal biceps brachii tendon repair: a systematic review of patient outcome determination using modified Coleman methodology score criteria.

PURPOSE: This systematic literature review evaluated the methodological research design quality of studies that evaluated patient outcomes following distal biceps brachii tendon repair and developed evidence-based recommendations for future patient clinical outcomes research. METHODS: Following the preferred reporting items for systematic reviews and meta-analyses criteria, and using "biceps brachii", "tendon", "repair" and "outcome assessment" search terms, the CINAHL, Academic Search Premier and MEDLINE databases were searched from January 1960-October 2015. The modified Coleman methodology score (MCMS) served as the primary outcome measure. Descriptive statistical analysis was performed for composite and component MCMS and for patient outcome assessment methodology use frequency. RESULTS: A total of 93 studies were evaluated. Overall MCMS was low (57.1 ± 14). Only 12 (12.9 %) had prospective cohort or randomized controlled trial designs. There was a moderate relationship between publication year and MCMS (r = 0.53, P < 0.0001). Although 61 studies (65.6 %) had adequate surgical descriptions, only 3 (3.2 %) had well-described rehabilitation. Of 2253 subjects, only 39 (1.7 %) were women. Studies published after 2008 had higher MCMS scores than studies published earlier (61.3 ± 10 versus 52.9 ± 16, P = 0.003). CONCLUSION: Although overall research study methodological scores improved on average since 2008, generally low MCMS scores, retrospective designs, lack of eccentric elbow flexor or supinator strength testing, and poorly described surgical and rehabilitation descriptions remain commonplace. These findings decrease clinical study validity and generalizability. LEVEL OF EVIDENCE: III.

Regenerative Anterior Cruciate Ligament Healing in Youth and Adolescent Athletes: The Emerging Age of Recovery Science.

Anterior cruciate ligament (ACL) injuries mainly arise from non-contact mechanisms during sport performance, with most injuries occurring among youth or adolescent-age athletes, particularly females. The growing popularity of elite-level sport training has increased the total volume, intensity and frequency of exercise and competition loading to levels that may exceed natural healing capacity. Growing evidence suggests that the prevailing mechanism that leads to non-contact ACL injury from sudden mechanical fatigue failure may be accumulated microtrauma. Given the consequences of primary ACL injury on the future health and quality of life of youth and adolescent athletes, the objective of this review is to identify key "recovery science" factors that can help prevent these injuries. Recovery science is any aspect of sports training (type, volume, intensity, frequency), nutrition, and sleep/rest or other therapeutic modalities that may prevent the accumulated microtrauma that precedes non-contact ACL injury from sudden mechanical fatigue failure. This review discusses ACL injury epidemiology, current surgical efficacy, the native ACL vascular network, regional ACL histological complexities such as the entheses and crimp patterns, extracellular matrix remodeling, the concept of causal histogenesis, exercise dosage and ligament metabolism, central nervous system reorganization post-ACL rupture, homeostasis regulation, nutrition, sleep and the autonomic nervous system. Based on this information, now may be a good time to re-think primary ACL injury prevention strategies with greater use of modified sport training, improved active recovery that includes well-planned nutrition, and healthy sleep patterns. The scientific rationale behind the efficacy of regenerative orthobiologics and concomitant therapies for primary ACL injury prevention in youth and adolescent athletes are also discussed.

Stress shielding following stemless anatomic total shoulder arthroplasty.

Background: Finite element analysis has suggested that stemless implants may theoretically decrease stress shielding. The purpose of this study was to assess the radiographic proximal humeral bone adaptations seen following stemless anatomic total shoulder arthroplasty. Methods: A retrospective review of 152 prospectively followed stemless total shoulder arthroplasty utilizing a single implant design was performed. Anteroposterior and lateral radiographs were reviewed at standard time points. Stress shielding was graded as mild, moderate, and severe. The effect of stress shielding on clinical and functional outcomes was assessed. Also, the influence of subscapularis management on the occurrence of stress shielding was determined. Results: At 2 years postoperatively, stress shielding was noted in 61 (41%) shoulders. A total of 11 (7%) shoulders demonstrated severe stress shielding with 6 occurring along the medial calcar. There was one instance of greater tuberosity resorption. At the final follow-up, no humeral implants were radiographically loose or migrated. There was no statistically significant difference in clinical and functional outcomes between shoulders with and without stress shielding. Patients undergoing a lesser tuberosity osteotomy had lower rates of stress shielding, which was statistically significant (p = 0.021). Discussion: Stress shielding does occur at higher rates than anticipated following stemless total shoulder arthroplasty, but was not associated with implant migration or failure at 2 years follow-up. Level of evidence: IV, Case series.

Arthroscopic suture bridge transosseus equivalent fixation of rotator cuff tendon preserves intratendinous blood flow at the time of initial fixation.

BACKGROUND: Current etiologic theories concerning healing rates in rotator cuff repair have focused on the blood supply in the tendinous portion of the cuff. We currently have little information regarding the effect of our repair techniques on this critical variable. We hypothesize that intratendinous blood flow is changed during transosseus equivalent tendon fixation. METHODS: Eighteen consecutive patients with rotator cuff tears amenable to double row fixation were included in the study. Each patient underwent a standard arthroscopic transosseous equivalent double row fixation procedure using the Arthrex SutureBridge technique (Arthrex, Naples, FL, USA). After tying down of the medial row, a first set of recordings was taken using a custom laser doppler flowmetry probe (Perimed, Inc., Ohio, USA). A second recording was made following securing of the lateral PushLock anchors. The data were compared to determine the overall effect on blood flow associated with this technique. RESULTS: Summated averages for the 2 groups show a significant (44.67%) decline in the blood flow present after the second row of implants are placed (P < .01). Individual calculations for regions of the cuff tear indicate significant differences in anterior third (P = .01), middle third (P < .01), and posterior third (P = .02) of the tear after transosseous equivalent fixation. CONCLUSION: Completion of the construct with lateral anchors in the transosseous equivalent technique results in reduced but preserved blood flow in the tendon repair site. Further study is required to determine the implications for tendon healing. CLINICAL RELEVANCE: Intratendinous blood flow is a variable that should be considered when evaluating repair methods in rotator cuff surgery.

Quadriceps tendon rupture: a biomechanical comparison of transosseous equivalent double-row suture anchor versus transosseous tunnel repair.

Quadriceps rupture off the patella is traditionally repaired by a transosseous tunnel technique, although a single-row suture anchor repair has recently been described. This study biomechanically tested a new transosseous equivalent (TE) double-row suture anchor technique compared with the transosseous repair for quadriceps repair. After simulated quadriceps-patella avulsion in 10 matched cadaveric knees, repairs were completed by either a three tunnel transosseous (TT = 5) or a TE suture anchor (TE = 5) technique. Double-row repairs were done using two 5.5 Bio-Corkscrew FT (fully threaded) (Arthrex, Inc., Naples, FL, USA) and two 3.5 Bio-PushLock anchors (Arthrex, Inc., Naples, FL, USA) with all 10 repairs done with #2 FiberWire suture (Arthrex, Inc., Naples, FL). Cyclic testing from 50 to 250 N for 250 cycles and pull to failure load (1 mm/s) were undertaken. Gap formation and ultimate tensile load (N) were recorded and stiffness data (N/mm) were calculated. Statistical analysis was performed using a Mann-Whitney U test and survival characteristics examined with Kaplan-Meier test. No significant difference was found between the TE and TT groups in stiffness (TE = 134 +/- 15 N/mm, TT = 132 +/- 26 N/mm, p = 0.28). The TE group had significantly less ultimate tensile load (N) compared with the TT group (TE = 447 +/- 86 N, TT = 591 +/- 84 N, p = 0.04), with all failures occurring at the suture eyelets. Although both quadriceps repairs were sufficiently strong, the transosseous repairs were stronger than the TE suture anchor repairs. The repair stiffness and gap formation were similar between the groups.

Supplemental bio-tenodesis improves tibialis anterior allograft yield load in extremely low density tibiae.

INTRODUCTION: Improved soft tissue tendon graft mechanical properties have led to their increased use for anterior cruciate ligament (ACL) reconstruction. Because they do not have an osseous component; however, there are greater concerns regarding tibial graft slippage during early postoperative rehabilitation and activities of daily living, particularly in patients with poor bone mineral density (BMD), such as older patients, women, smokers, and patients undergoing revision ACL reconstruction surgery. METHODS: This in vitro biomechanical study attempted to determine the effectiveness of supplemental ACL graft fixation in low BMD tibiae. Eight paired knees (16 specimens) were harvested from female cadavers (mean age = 76, range = 60-88 years). Tibiae were assigned to either a combination bioabsorbable interference screw, bio-tenodesis screw group (Group 1, n = 8, apparent BMD = 0.44 ± 0.13 g/cm(2)) or a bioabsorbable interference screw group (Group 2, n = 8, apparent BMD = 0.44 ± 0.14 g/cm(2)). Double-strand (single loop) tibialis anterior tendon allografts were fixed in matched diameter tibial tunnels. Using a custom 6° of freedom jig, potted constructs were mounted on to a servo hydraulic device with the axial loading force aligned directly with the tibial tunnel. Constructs underwent progressive cyclic tensile loading from 10 to 150 N with a 25 N load increase every 20 cycles. This was followed by yield load to failure testing (20 mm/min). RESULTS: Groups did not display displacement differences during progressive cyclic loading. Group 1 (312.7 ± 67.5 N) displayed 25% greater yield load at failure than Group 2 (235.0 ± 47.6 N), P = 0.045. Both groups displayed fixation levels well below the previously reported minimal safe threshold estimate for early unrestricted weight bearing, accelerated rehabilitation and activities of daily living. CONCLUSION: Supplemental bio-tenodesis fixation may improve early tibial-soft tissue tendon graft fixation in patients that have poor tibial BMD, but study results suggest that both methods may require weightbearing, rehabilitation, and activity of daily living restrictions during the early postoperative period to prevent graft slippage.

Trunk and lower extremity long-axis rotation exercise improves forward single leg jump landing neuromuscular control.

BACKGROUND: Anterior cruciate ligament (ACL) injuries often involve sudden single leg loading with directional changes. Trunk and lower extremity (LE) load transfer and muscle power are directly coupled during these movements. The effect of trunk and LE long-axis rotation training on forward single leg drop jump landing and stabilization (FSLDJLS) was studied. METHODS: Using block randomization (gender), 36 (18 men, 18 women) subjects were assigned to experimental (nine, 20 min exercise sessions) and control groups with equal subject number. Ground reaction force (1000 Hz), kinematic (60 Hz) and LE EMG (1000 Hz) data were synchronously collected. Statistical analysis compared pre- and post-test neuromuscular control mean change differences (MCD), and hip flexion-LE peak EMG % maximum volitional isometric contraction (%MVIC) (expressed as decimal equivalents), mean change difference (MCD) relationships. RESULTS: The experimental group had greater landing knee flexion (3.5 ± 3.6° vs. -0.4 ± 3.3°, p = .002) MCD, greater dynamic LE stiffness after landing (0.09 ± 0.14 vs. -0.11 ± 0.14, p = .001) MCD, and increased gluteus maximus (GMAX) (0.20 ± 0.39%MVIC vs. -0.23 ± 0.46%MVIC, p = .006) and gluteus medius (GMED) EMG amplitude (0.22 ± 0.31 vs. -0.07 ± 0.36%MVIC, p = .018) MCD. This group also had decreased GMAX (-166.5 ± 403.6 ms vs. 89.3 ± 196 ms, p = .025), GMED (-75.9 ± 126.8 ms vs. 131.2 ± 207.1 ms, p = .002) and vastus lateralis (-109.1 ± 365 ms vs. 205.5 vs. 510 ms, p = .04) activation duration MCD. More experimental group subjects had increased landing knee flexion MCD (15/18 vs. 8/18, p = .015), increased dynamic LE stiffness MCD (15/18 vs. 2/18, p < .0001) and increased GMAX (15/18 vs. 7/18, p = .006) and GMED (17/18 vs. 10/18, p = .007) EMG amplitude MCD, and reduced GMAX (12/18 vs. 6/18, p = .046), GMED (11/18 vs. 5/18, p = .044), rectus femoris (12/18 vs. 6/18, p = .046), and vastus lateralis (13/18 vs. 7/18, p = .044) EMG activation duration MCD. Only the experimental group displayed significant relationships between landing and peak hip flexion and peak LE EMG amplitude MCD. CONCLUSION: Increased dynamic LE stiffness, increased hip muscle EMG amplitude and decreased hip and knee muscle activation duration MCD in the experimental group suggests improved LE neuromuscular control.

Sex-related differences in stemless total shoulder arthroplasty.

BACKGROUND: The use of stemless humeral implants for shoulder arthroplasty is becoming increasingly widespread. However, little is known about the difference in clinical, functional, and radiographic outcomes of stemless shoulder arthroplasty between men and women. Men and women do have reported differences in size, strength, and bone quality. As such, the purpose of this study was to evaluate sex-related differences in outcomes when using stemless humeral implants. METHODS: A retrospective review of 227 patients (men = 143 and women = 84) undergoing stemless shoulder arthroplasty was compared for sex-related differences. Clinical, functional, and radiographic outcomes were compared, including American Shoulder and Elbow Surgeons (ASES) scores, visual analog scale pain scores, range of motion, radiolucencies, operative data, implant data, and complications. Statistical analysis included descriptive statistics, t-tests, chi-square tests, and logistic regression. RESULTS: Preoperatively, men had a statistically significant greater range of motion of forward elevation (P < .01), external rotation (ER) at adduction (P = .04), ER at 90° abduction (P = .03), and baseline ASES scores (P < .01). At 2 years, there were no differences between men and women in ASES score (P = .12), visual analog scale pain score (P = .74), active ER (P = .98), implant migration, or radiolucencies (P > .99). Mean operating time was 9 minutes longer in male patients (P < .01). There was no significant difference in surgical complications, including dislocation, fracture, infection, or loosening. The three-year revision-free survival was 98.8% for women and 97.9% for men. CONCLUSION: Patient sex is not predictive of postoperative functional outcomes after stemless shoulder arthroplasty. The operative time was significantly shorter in female patients, and there was no significant difference in surgical complications between men and women.

Femoral cross-pin safety in anterior cruciate ligament reconstruction as a function of femoral tunnel position and insertion angle.

PURPOSE: To compare femoral cross-pin guidewire insertion at differing angles to identify "safe zones" relative to saphenous nerve, popliteus tendon, fibular collateral ligament, peroneal nerve, and femoral artery/vein locations between transtibial and medial-portal femoral tunnel drilling methods. METHODS: Five paired cadaveric knees were randomly assigned to a transtibial or medial-portal femoral (anatomic) tunnel drilling group. Guidewires were inserted at differing frontal plane angles (+10°, 0°, -10°, and -20°). Distances between the guidewire and the anatomic structure of interest were measured with an electronic caliper. RESULTS: Two-way analysis of variance showed that guidewire angle, not tunnel drilling method, created significant differences between guidewire-saphenous nerve (P < .001) and guidewire-femoral artery/vein (P < .001) distances. The +10° angle showed a shorter guidewire-saphenous nerve distance than the 0°, -10°, and -20° angles. The +10° angle also showed a shorter guidewire-femoral artery/vein distance than the -10° and -20° angles, and the 0° insertion angle created a shorter guidewire-femoral artery/vein distance than the -10° and -20° angles. Fisher exact tests showed that guidewires inserted at a +10° angle showed a greater incidence of safe-zone violations for the saphenous nerve (P = .04) and femoral artery/vein (P < .0001). CONCLUSIONS: Insertion angle, not tunnel drilling method, influenced saphenous nerve and femoral artery/vein injury risk. At the +10° angle, the saphenous nerve and femoral artery/vein are at greater risk for surgically induced injury. Guidewire insertion at -10° or -20° angles should increase concerns about potential popliteus tendon and fibular collateral ligament injury. CLINICAL RELEVANCE: Insertion angle, not tunnel drilling method, influenced saphenous nerve and femoral artery/vein injury risk.

Treatment of Partial-Thickness Rotator Cuff Tears With a Resorbable Bioinductive Bovine Collagen Implant: 1-Year Results From a Prospective Multicenter Registry.

BACKGROUND: Surgical treatment of partial-thickness rotator cuff tears remains challenging and controversial, with several traditional options including debridement with acromioplasty, transtendon or in situ repair, and take-down and repair. A resorbable bioinductive bovine collagen implant has shown promise as an alternative treatment option for partial-thickness tears. PURPOSE: Data from a registry were analyzed to further establish that the implant contributes to improved patient-reported outcome (PRO) scores across a large number of patients treated for partial-thickness rotator cuff tears. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 19 centers in the United States enrolled patients >21 years old with partial-thickness tears of the rotator cuff in a comprehensive prospective multicenter registry. PRO scores were recorded preoperatively and postoperatively at 2 and 6 weeks, 3 and 6 months, and 1 year: American Shoulder and Elbow Surgeons, Single Assessment Numeric Evaluation, Veterans RAND 12-Item Health Survey (physical and mental component scores), and Western Ontario Rotator Cuff scores. Revisions were reported throughout the study. RESULTS: The registry included 272 patients with partial-thickness tears (49 grade 1 tears, 101 grade 2 tears, and 122 grade 3 tears), 241 who underwent isolated bioinductive repair (IBR; collagen implant placed after bursectomy without a traditional rotator cuff repair), and 31 who had take-down and repair with bioinductive augmentation. Patients experienced statistically significant and sustained improvement from baseline for all PRO scores beginning at 3 months. Among patients with grade ≥2 tears, those with take-down and repair had significantly inferior scores at 2 and 6 weeks for most PRO scores as compared with those who underwent IBR, but the difference was no longer significant at 1 year for all but the physical component score of the Veterans RAND 12-Item Health Survey. There were 11 revisions, which occurred at a mean ± SD of 188.7 ± 88.0 days after the index surgery. There were no infections. CONCLUSION: This registry analysis further establishes across a large data set that this resorbable bioinductive bovine collagen implant improves PROs in all grades of partial-thickness tears, whether used as IBR or in conjunction with take-down and repair. IBR may offer improved early clinical outcomes (≤6 weeks) and comparable outcomes at 1 year when compared with a more invasive "take-down and repair" approach.