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Background: The acetabular labrum has been found to provide a significant contribution to the distractive stability of the hip. However, the influence of labral height on hip suction seal biomechanics is not known. Hypothesis: The smaller height of acetabular labrum is associated with decreased distractive stability. Study Design: Descriptive laboratory study. Methods: A total of 23 fresh-frozen cadaveric hemipelvises were used in this study. Hips with acetabular dysplasia or femoroacetabular impingement–related bony morphologic features, intra-articular pathology, or no measurable suction seal were excluded. Before testing, each specimen’s hip capsule was removed, a pressure sensor was placed intra-articularly, and the hip was fixed in a heated saline bath. Labral size was measured by use of a digital caliper. Maximum distraction force, distance to suction seal rupture, and peak negative pressure were recorded while the hip underwent distraction at a rate of 0.5 mm/s. Correlations between factors were analyzed using the Spearman rho, and differences between groups were detected using Mann-Whitney U test. Results: Of 23 hips, 12 satisfied inclusion criteria. The maximum distraction force and peak negative pressure were significantly correlated ( R = −0.83; P = .001). Labral height was largely correlated with all suction seal parameters (maximum distraction force, R = 0.69, P = .013; distance to suction seal rupture, R = 0.55, P = .063; peak negative pressure, R = −0.62, P = .031). Labral height less than 6 mm was observed in 5 hips, with a mean height of 6.48 mm (SD, 2.65 mm; range, 2.62-11.90 mm; 95% CI, 4.80-8.17 mm). Compared with the 7 hips with larger labra (>6 mm), the hips with smaller labra had significantly shorter distance to suction seal rupture (median, 2.3 vs 7.2 mm; P = .010) and significantly decreased peak negative pressure (median, −59.3 vs −66.9 kPa; P = .048). Conclusion: Smaller height (<6 mm) of the acetabular labrum was significantly associated with decreased distance to suction seal rupture and decreased peak negative pressure. A new strategy to increase the size of the labrum, such as labral augmentation, could be justified for patients with smaller labra in order to optimize the hip suction seal. Clinical Relevance: The height of the acetabular labrum is correlated with hip suction seal biomechanics. Further studies are required to identify the clinical effects of labral height on hip stability.

Background: Glenoid bone loss (GBL) has been implicated as a risk factor for failure of arthroscopic anterior glenohumeral instability repair. Although certain amounts of GBL are associated with higher recurrence rates, there are limited studies on successes versus failures in these cohorts. Purpose: To compare the outcomes of arthroscopic Bankart repair in patients with and without GBL to determine a threshold percentage of GBL that predicts success. Study Design: Cohort study; Level of evidence, 2. Methods: All consecutive patients who underwent arthroscopic Bankart repair for anterior shoulder instability between 2004 and 2013 were prospectively enrolled. Patients with ≤25% GBL were included. Patients with no GBL were grouped and compared with those having 5% to 25% GBL. Outcomes included Single Assessment Numerical Evaluation, Western Ontario Shoulder Index, and American Shoulder and Elbow Surgeons scores, with evidence of recurrent instability. Patients with and without GBL were statistically compared with respect to outcomes and recurrence rates. Results: Of 434 eligible patients, the cases of 405 (45 female, 360 male; mean age, 27.5 years [range, 18-47 years]) were followed for a mean 61 months (range, 48-96 months). There were 189 (46.6%) with no GBL and 216 (53.3%) with GBL; the mean GBL of the latter cohort was 15% (range, 5%-25%). The mean duration of instability symptoms was 7.9 months (range, 1-21 months) and was significantly longer in the GBL group ( P < .05). The mean recurrence rate was 14.8%, which was significantly greater in patients presenting with GBL versus those with none (48/216 [22.2%] vs 12/189 [6.3%]; P < .01). Within the GBL group, GBL ≥15%, duration of symptoms >5 months, and younger age (<20 years) were independent risk factors for failure ( P < .01). Patients with any GBL had >4-times greater odds of recurrence after arthroscopic stabilization (odds ratio, 4.21; 95% CI, 2.16-8.21). Moreover, patients presenting for arthroscopic Bankart repair with GBL ≥15% had nearly 3-times greater odds of recurrent instability. Conclusion: GBL ≥15% in an active patient population portends to increased odds of recurrent instability events and inferior clinical outcomes after arthroscopic Bankart repair. Furthermore, nonmodifiable risk factors, such as age (<20 years) and duration of symptoms before presentation (>5 months), significantly affect risk of recurrence and should be key factors when counseling patients on risk of failure and determining the ideal procedure for the individual patient.

Background: Subpectoral biceps tenodesis can be performed with cortical fixation using different repair techniques. The goal of this technique is to obtain a strong and stable reduction of biceps tendon in an anatomic position. Purpose/Hypothesis: The purpose of this study was to compare (1) displacement during cyclic loading, (2) ultimate load, (3) construct stiffness, and (4) failure mode of the biceps tenodesis fixation methods using onlay techniques with an all-suture anchor versus an intramedullary unicortical button. It was hypothesized that fixation with all-suture anchors using a Krackow stitch would exhibit biomechanical characteristics similar to those exhibited by fixation with unicortical buttons. Study Design: Controlled laboratory study. Methods: Ten pairs of fresh-frozen cadaveric shoulders (N = 20) were dissected to the humerus, leaving the biceps tendon-muscle unit intact for testing. A standardized subpectoral biceps cortical (onlay) tenodesis was performed using either an all-suture anchor or a unicortical button. The biceps tendon was initially cycled from 5 to 70 N at a frequency of 1.5 Hz. The force on the tendon was then returned to 5 N, and the tendon was pulled until ultimate failure of the construct. Displacement during cyclic loading, ultimate failure load, stiffness, and failure modes were assessed. Results: Cyclic loading resulted in a mean displacement of 12.5 ± 2.5 mm for all-suture anchor fixation and 29.2 ± 9.4 mm for unicortical button fixation ( P = .005). One all-suture anchor fixation and 2 unicortical button fixations failed during cyclic loading. The mean ultimate failure load was 170.4 ± 68.8 N for the all-suture anchor group and 125.4 ± 44.6 N for the unicortical button group ( P = .074), with stiffness 59.3 ± 11.6 N/mm and 48.6 ± 6.8 N/mm ( P = .091), respectively. For the unicortical button, failure occurred by suture tearing through tendon in 100% of the specimens. For the all-suture anchor, failure occurred by suture tearing through tendon in 56% and knot failure in 44% of the specimens. Conclusion: The all-suture anchor fixation using a Krackow stitch for subpectoral biceps tenodesis provided ultimate load and stiffness similar to unicortical button fixation using a nonlocking whipstitch. The all-suture anchor fixation technique was shown to be superior in terms of displacement during cyclic loading when compared with the unicortical button fixation technique. However, the results of this study help to show that the fixation method used on the humeral side is less implicative of the overall construct strength than stitch location and technique, as the biceps tendon tissue and stitch configuration seem to be the limiting factor in subpectoral onlay tenodesis techniques. Clinical Relevance: All-suture anchors have a smaller diameter than traditional suture anchors, can be inserted through curved guides, and preserve humeral bone stock without compromising postoperative imaging. This study supports use of the all-suture anchor fixation technique for subpectoral biceps tenodesis, with high biomechanical fixation strength and low displacement, as an alternative to the subpectoral onlay biceps tenodesis technique.

Background: Instability of the sternoclavicular (SC) joint is a rare but potentially devastating pathologic condition, particularly when it occurs in young or active patients, where it can lead to persistent pain and impairment of shoulder function. SC joint reconstruction using a hamstring tendon autograft is a commonly used treatment option, but midterm results are still lacking. Purpose/Hypothesis: The purpose of this study was to assess the clinical outcomes, survivorship, and return-to-sports rate after SC joint reconstruction using a hamstring tendon autograft in patients suffering from SC joint instability. We hypothesized that SC joint reconstruction would result in good clinical outcomes, high rate of survivorship, and a high rate of return to sports. Study Design: Case series; Level of evidence, 4. Methods: All patients who underwent SC joint reconstruction with a hamstring tendon autograft for SC joint instability, with a minimum 5-year follow-up, were included. Patient-reported outcomes were assessed prospectively by the use of the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numerical Evaluation (SANE) score, short version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, 12-Item Short Form Health Survey (SF-12) physical component summary (PCS), and patient satisfaction. Survivorship of reconstruction was defined as no further revision surgery or clinical failure such as recurrent instability or subluxation events. Return to sports and pain were assessed using a customized questionnaire. Results: A total of 22 shoulders that underwent SC joint reconstruction, with a mean patient age of 31.3 years (range, 15.8-57.0 years) at the time of surgery, were included. At the final evaluation, 18 shoulders, with a mean follow-up of 6.0 years (range, 5.0-7.3 years), completed a minimum 5-year follow-up. All clinical outcome scores improved significantly from preoperatively to postoperatively: ASES (50.0 to 91.0; P = .005), SANE (45.9 to 86.0; P = .007), QuickDASH (44.2 to 12.1; P = .003), and SF-12 PCS (39.4 to 50.9; P = .001). Median postoperative satisfaction was 9 (range, 7-10). The construct survivorship was 90% at 5-year follow-up. There were 2 patients with failed treatment at 82 and 336 days postoperatively because of instability or pain who underwent revision SC joint reconstruction and capsulorrhaphy. Another patient had a superficial wound infection, which was debrided once and resulted in a good clinical outcome. Of the patients who answered optional sports activity questions, 15 (17 shoulders, 77%) participated in recreational or professional sports before the injury. At final follow-up, 14 patients (16 of 17 shoulders, 94%) returned to their preinjury level of sports. The visual analog scale score for pain today ( P = .004) and pain at its worst ( P = .004) improved significantly from preoperatively to postoperatively. Conclusion: SC joint reconstruction with a hamstring tendon autograft for SC joint instability resulted in significantly improved clinical outcomes with high patient satisfaction and 90% survivorship at midterm follow-up. Furthermore, 94% of this young and high-demand patient population returned to their previous level of sports. Concerns in terms of advanced postinstability arthritis were not confirmed because a significant decrease in pain was found after a minimum 5-year follow-up.