A Tensionable Suture-based Cerclage Is an Alternative to Stainless Steel Cerclage Fixation for Stabilization of a Humeral Osteotomy During Shoulder Arthroplasty.

INTRODUCTION: Fixation of periprosthetic humeral fractures is most commonly obtained with steel-based wires or cables; however, disadvantages with these constructs are numerous. Suture-based cerclages offer the advantage of easy handling, less radiographic interference, and risk of metallosis, as well as decreased risk of cutting into the soft humeral bone. Therefore, the purpose of this study was to compare a suture-based cerclage to a stainless steel wire cerclage (SSWC) for stabilization of the humerus during shoulder arthroplasty. METHODS: In part I of the study, SSWC fixation was compared with single-looped tape cerclage and a double-looped tape cerclage (DLTC) fixation. In part II, a subsidence test was performed on 12 cadaveric humeri. After an osteotomy, the humeri were secured with either a SSWC or DLTC. Subsequently, a metal wedge was introduced into the humerus to simulate the stem of a shoulder arthroplasty. RESULTS: In part I, load to 2-mm displacement was significantly higher for the DLTC construct compared with the SSWC construct (2,401 ± 483 N versus 750 ± 33 N; P < 0.0001). Load to failure was 935 ± 143 N with the SSWC, 1,737 ± 113 N with the single-looped tape cerclage, and 4,360 ± 463 N with the DLTC constructs, and all differences were statistically significant (P < 0.05). In part II, load at 20-mm subsidence was higher for the DLTC (320 ± 274 N) compared with the SSWC (247 ± 137 N), but no significant difference was observed (P > 0.05). However, gap displacement at 20 mm subsidence was significantly lower with the DLTC construct (0.33 ± 0.31 mm versus 0.77 ± 0.23 mm; P = 0.009). Load to failure was higher with the DLTC construct compared with the SSWC construct (4,447 ± 2,325 N versus 1,880 ± 1,089 N; P = 0.032), but the final gap displacement did not differ significantly (DLTC 5.23 ± 6.63 mm versus SSWC 6.03 ± 8.82 mm; P > 0.05). DISCUSSION: A DLTC has higher load to failure and trends toward lower gap displacement compared with a SSWC. The DLTC construct may therefore be a viable alternative for fixation of periprosthetic fractures or osteotomies of the humeral shaft during shoulder arthroplasty.

Does Arthroscopic Simulation Training Improve Triangulation and Probing Skills? A Randomized Controlled Trial✰.

OBJECTIVE: To determine the effectiveness of simulator training on basic arthroscopic skills utilizing a novel, low-cost arthroscopic triangulation training system. DESIGN: A randomized controlled trial of subjects without prior arthroscopy training was conducted, with participants randomized to receive either a fixed protocol of simulation training on a triangulation simulation model (30 minutes of training for 4 consecutive days), or no training. On Days 1 and 5, all participants were evaluated on 3 simulated arthroscopic tasks by an independent observer. Variables analyzed included how many times portals were changed, the time it took to complete the tasks, and the task completion rate. SETTING: Arthrex Inc., Naples, FL. PARTICIPANTS: Thirty-six participants (92% male, average 28 ± 5 years) with no prior arthroscopy training were randomized into 2 groups, with 17 in the training group (T) and 19 in the no-training group (NT). RESULTS: On Day 1, there was no difference in rate of task completion between the T group and NT groups (41% versus 53%, p = 0.52). On Day 5, significantly more participants in the T group completed all tasks compared to the NT group (100% versus 63%, p = 0.008). Participants in the T group had significantly improved task completion times on Day 5 versus Day 1 (p < 0.05). Participants in the NT group had a significantly improved task completion time for Task 1 on Day 5 versus Day 1 (p = 0.037); no differences were found for Tasks 2 or 3. On Day 5, participants in the T group required significantly fewer portal changes compared to the NT group (2.35 ± 2.29 versus 6.95 ± 8.55, p = 0.039). CONCLUSIONS: Simulation training on a simple, low-cost arthroscopic triangulation training system resulted in an overall improvement in arthroscopic probing and triangulation skills within 1 week of training, with significantly decreased task completion times and increased efficiency of movement.

The Rotator Cuff and the Superior Capsule: Why We Need Both.

Tears of the rotator cuff are frequent. An estimated 250,000 to 500,000 repairs are performed annually in the United States. Rotator cuff repairs have been successful despite fatty infiltration and atrophy of the rotator cuff muscles. Although the emphasis in rotator cuff repair has historically focused on re-establishing the tendon attachment, there is growing interest in and understanding of the role of the superior capsule. The superior capsule is attached to the undersurface of the supraspinatus and infraspinatus muscle-tendon units, and it resists superior translation of the humeral head. Herein, we propose that it is the defect in the superior capsule that is the "essential lesion" in a superior rotator cuff tear, as opposed to the defect in the rotator cuff itself. We propose that rotator cuff repair must restore the normal capsular anatomy to provide normal biomechanics of the joint and thus a positive clinical outcome.