Kwapisz, Adam

Background: Clinical trials are currently underway to investigate the efficacy of intra-articular administration of mesenchymal stromal cells (MSCs) to mitigate osteoarthritis (OA) progression in the knee. Although multiple MSC sources exist, studies have yet to determine whether differences in therapeutic efficacy exist between them. Purpose: To compare the ability of intra-articularly injected adipose-derived MSCs (AD-MSCs) and amnion-derived MSCs (AM-MSCs) to mitigate the progression of knee OA in a small animal model of spontaneous OA, as well as to compare the therapeutic potential of MSCs in hyaluronic acid (HA) and in HA only with saline (OA) controls. Study Design: Controlled laboratory study. Methods: Injections of AD-MSCs or AM-MSCs suspended in HA or HA only were performed in the rear stifle joints of 3-month-old Dunkin Hartley guinea pigs (DHGPs). Repeat injections occurred at 2 and 4 months after the initial injection in each animal. Contralateral limbs received saline injections and served as untreated controls. Subsequently, joints were analyzed for osteoarthritic changes of the cartilage and subchondral bone via histologic and biochemical analyses. To evaluate MSC retention time in the joint space, DHGPs received a single intra-articular injection of fluorescently labeled AD-MSCs or AM-MSCs, and the fluorescence intensity was longitudinally tracked via an in vivo imaging system. Results: No statistically significant differences in outcomes were found when comparing the ability of AD-MSCs and AM-MSCs to mitigate OA. However, the injection of AD-MSCs, AM-MSCs, and HA-only treatments more effectively mitigated cartilage damage compared with that of saline controls by demonstrating higher amounts of cartilage glycosaminoglycan content and improved histological proteoglycan scoring while reducing the percentage of osteophytes present. Conclusion: Intra-articular injection of AD-MSCs, AM-MSCs, or HA only was able to similarly mitigate the progression of cartilage damage and reduce the percentage of osteophytes compared with that of saline controls in the DHGP. However, this study was unable to establish the superiority of AD-MSCs versus AM-MSCs as a treatment to mitigate spontaneous OA. Clinical Relevance: MSCs demonstrate the ability to mitigate the progression of knee OA and thus may be used in a prophylactic approach to delay the need for end-stage treatment strategies.

Background: Functional bracing is often used as an adjunct to nonoperative treatment of anterior shoulder instability, but no study has evaluated the effectiveness of in-season bracing. The purpose of this study was to examine successful return to play in a nonoperative cohort of adolescent athletes with in-season shoulder instability and compare those athletes treated with bracing to those who were not. Hypothesis: The use of functional bracing will improve success rates in a cohort of athletes treated nonoperatively for in-season shoulder instability. Study Design: Cohort study. Level of Evidence: Level 3. Methods: A total of 97 athletes with anterior shoulder instability were followed for a minimum of 1 year. The mean age was 15.8 ± 1.4 years (range, 12.0-18.0 years). All athletes were treated with initial nonoperative management. Twenty athletes (21%) were also treated with bracing while 77 (79%) were not. The athlete completing the current season and 1 subsequent season without surgery or time lost from shoulder injury was defined as a successful outcome. Results: There was no statistical difference in nonoperative success rates between the braced and nonbraced athletes ( P = 0.33). Braced athletes (n = 20) returned to play 80% of the time, while nonbraced athletes (n = 77) returned at a rate of 88%. Of the braced athletes, 85% were football players (n = 17). A football-only comparison demonstrated no difference between braced failures (26%) and nonbraced failures (16%) ( P = 0.47). Conclusion: This is the first study to evaluate the utility of functional bracing in returning an athlete to sport and completing a full subsequent season without surgery or time loss due to injury of the shoulder. In adolescent athletes with shoulder instability treated nonoperatively, functional bracing did not result in increased success rates when compared with no bracing. Clinical Relevance: The data from this study indicate that functional bracing may not improve success rates for athletes with shoulder instability.

Background: Young age and contact sports have been postulated as risk factors for anterior shoulder instability. Management after shoulder instability is controversial, with studies suggesting that nonoperative management increases the risk of recurrence. Several studies examined return to play after an in-season instability episode, and few followed these patients to determine if they were able to successfully compete in a subsequent season. No study has evaluated this question in a high school athlete population. Purpose: To compare the likelihood of return to scholastic sport and complete the next full season without an additional time-loss injury among athletes with anterior shoulder instability in terms of treatment, instability type, and sport classification. Study Design: Cohort study; Level of evidence, 2 Methods: Athletes were included in this study as identified by a scholastic athletic trainer as experiencing a traumatic time-loss anterior shoulder instability injury related to school-sponsored participation. The cohort was predominantly male (n = 108, 84%) and consisted mostly of contact athletes (n = 101, 78%). All athletes had dislocation or subluxation diagnosed by a board-certified physician who determined the athlete’s course of care (nonoperative vs operative). Successful treatment was defined as completion of care and return to the athlete’s index sport, with full participation for the following season. Chi-square and relative risk analyses were completed to compare success of treatment (nonoperative vs operative care) and instability type. Separate logistic regressions were used to compare the effect of sex and sport classification on the athletes’ ability to return to sport. Statistical significance was set a priori as α = .05. Results: Scholastic athletes (N = 129) received nonoperative (n = 97) or operative (n = 32) care. Nonoperatively treated (85%) and operatively treated (72%) athletes successfully returned to the same sport without injury for at least 1 full season ( P = .11). Players sustaining a dislocation were significantly more likely to fail to return when compared with those sustaining a subluxation (26% vs 89%, P = .013). Sex ( P = .85) and sport classification ( P = .74) did not influence the athlete’s ability to return to sport, regardless of treatment type. Conclusion: A high percentage of athletes with shoulder instability achieved successful return to sport without missing any additional time for shoulder injury. Those with subluxations were at almost 3 times the odds of a successful return compared with those sustaining a dislocation.

Background: Controversy exists as to whether the subscapularis should be repaired after reverse shoulder arthroplasty. The purpose of the present study was to evaluate the utility of repairing the subscapularis after reverse shoulder arthroplasty with regard to complications, objective findings, and patient-reported outcome measures. Methods: We retrospectively reviewed the records for 99 patients who had undergone a lateralized reverse shoulder arthroplasty with (n = 58) or without (n = 41) subscapularis repair. Outcomes were compared with the Single Assessment Numeric Evaluation (SANE), Penn shoulder score (PSS), Veterans RAND (VR)-12, and American Shoulder and Elbow Surgeons (ASES) score at a minimum of 2 years of follow-up. Demographics, range of motion, and complications were also compared. A 1-way analysis of variance was performed to determine differences in performance and outcome scores, and a chi-square analysis was performed to compare the frequency of complications between groups. Results: There were no significant differences between the repair and no-repair groups in terms of SANE, PSS, ASES, or VR-12 scores. There also were no significant differences between the 2 groups in terms of postoperative ranges of forward elevation (128° versus 123°; p = 0.44) and external rotation (33° versus 29°; p = 0.29), the dislocation rate (5% versus 2%; p = 0.49), or the overall complication rate (9% versus 5%; p = 0.47). Conclusions: The results of the present study suggest that repair of the subscapularis tendon after lateralized reverse shoulder arthroplasty may not be necessary. Level of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Background: Bone loss in shoulder instability is a well-recognized cause of failure after stabilization surgery. Many approaches have been described to address glenoid bone loss, including coracoid transfer. This transfer can be technically difficult and has been associated with high complication rates. An ideal alternative to coracoid transfer would be an autologous source of fresh osteochondral graft with enough surface area to replace significant glenoid bone loss. The distal clavicle potentially provides such a graft source that is readily available and low-cost. Purpose: To evaluate distal clavicular autograft reconstruction for instability-related glenoid bone loss, specifically comparing the width of the clavicular autograft with the width of an ipsilateral coracoid graft as prepared for a Latarjet procedure. Further, we sought to compare the articular cartilage thickness of the distal clavicle graft with that of the native glenoid. Study Design: Controlled laboratory study. Methods: Twenty-seven fresh-frozen cadaver specimens were dissected, and an open distal clavicle excision was performed. The coracoid process in each specimen was prepared as has been described for a classic Latarjet coracoid transfer. In each specimen, the distal clavicle graft was compared with the coracoid graft for size and potential of glenoid articular radius of restoration. The distal clavicle graft was also compared with the native glenoid for cartilage thickness. Results: In all specimens, the distal clavicle grafts provided a greater radius of glenoid restoration than the coracoid grafts ( P < .0001). On average, the clavicular graft was able to reconstruct 44% of the glenoid diameter, compared with 33% for the coracoid graft ( P < .0001). The articular cartilage of the glenoid was significantly thicker (1.4 mm thicker, P < .0001) than that of the distal clavicular autograft (average ± SD, 3.5 ± 0.6 mm vs 2.1 ± 0.8 mm, respectively). When specimens with osteoarthritis were excluded, this difference decreased to 0.97 mm when compared with the clavicular cartilage ( P = .0026). Conclusion: The distal clavicle autograft can restore a significantly greater glenoid bone deficit than the Latarjet procedure and has the additional benefit of restoring articular cartilage to the glenoid. The articular cartilage thickness of the distal clavicle is within 1.4 mm of that of the native glenoid. Clinical Relevance: The distal clavicular autograft may be a suitable option for reconstruction of instability-related glenoid bone loss. This graft provides a structural osteochondral autograft with a broader radius of reconstruction than that of a coracoid graft, is locally available, has minimal donor site morbidity, is anatomic, and provides articular cartilage.