Rotator cuff injury as a complication of portal placement for superior labrum anterior-posterior repair.

BACKGROUND: An accessory trans-rotator cuff portal is commonly used in shoulder arthroscopy, primarily in the repair of SLAP (superior labrum anterior-posterior) lesions. Improper placement of the trans-rotator cuff portal can result in damage to the rotator cuff near its attachment site. METHODS: Six patients were studied, having been referred to our clinic after previous shoulder arthroscopy with SLAP repair. Review of operative notes showed that the rotator cuff had been described as normal in 5 patients and having a mild partial-thickness tear of the supraspinatus in 1 patient at the time of the first surgery. All patients underwent repeat shoulder arthroscopy within 10 to 22 months. RESULTS: All 6 patients were found to have full-thickness rotator cuff tears at the time of the second surgery. The rotator cuff injuries appeared to be associated with portal placement from the previous SLAP repair. All patients underwent rotator cuff repair, and 3 had concomitant revision SLAP repair. All patients had clinical improvement, with a mean preoperative American Shoulder and Elbow Surgeons score of 45.3 and mean postoperative score of 90.5. Mean follow-up was 58.3 months. CONCLUSIONS: Proper placement of a trans-rotator cuff portal should be performed cautiously, traversing the rotator cuff medial to the muscle-tendon junction. This report highlights the potential for injury to the rotator cuff tendons with improper placement of this portal. In patients with persistent pain after previous SLAP repair with a trans-rotator cuff portal technique, rotator cuff injury may be the source of symptoms. Revision surgery with rotator cuff repair can provide improvement.

Effect of humeral component version on impingement in reverse total shoulder arthroplasty.

HYPOTHESIS: Reverse shoulder arthroplasty is growing in popularity for patients with deficient rotator cuffs; however, the phenomenon of scapular notching continues to be a concern. This study examined the effects of humeral component version in the Aequalis Reversed Shoulder Prosthesis (Tornier, Edina, MN) on impingement of the humeral prosthesis against the scapula to test the hypothesis that the mechanical contact of the humeral component with the scapular neck is influenced by the version of the humeral component. MATERIALS AND METHODS: Seven shoulders from deceased donors were tested after the Aequalis Reversed Shoulder was implanted. The deltoid, pectoralis major, and latissimus dorsi were loaded based on physiologic cross-sectional area. The degree of internal and external rotation when impingement, subluxation, or dislocation occurred was measured at 0°, 30°, and 60° glenohumeral abduction in the scapular plane. Testing was performed with the humeral component placed in 20° of anteversion, neutral version, 20° of retroversion, and 40° of retroversion. RESULTS: Maximum external rotation at 0° abduction was -1° ± 4° at 20° anteversion, 15° ± 3° at neutral, 28° ± 4° at 20° retroversion, and 44° ± 5° at 40° retroversion (P < .05). Maximum internal rotation at 0° abduction was 128° ± 9° at 20° anteversion, 112° ± 9° at neutral, 99° ± 8° at 20° retroversion, and 83° ± 8° at 40° retroversion (P < .05). Maximum external rotation at 30° abduction was 70° ± 6° at 20° anteversion, 84° ± 7° at neutral, 97° ± 6° at 20° retroversion, and 110° ± 5° at 40° retroversion (P < .05). There was no limitation to internal rotation at 30° abduction. No impingement occurred at 60° abduction. DISCUSSION: Version of the humeral component plays a role in range of motion and impingement in reverse total shoulder arthroplasty. Anteversion can significantly decrease the amount of external rotation achievable after reverse total shoulder surgery. CONCLUSION: Placing the Aequalis Reversed Shoulder humeral component at between 20° and 40° of retroversion more closely restores a functional arc of motion without impingement.