Anterior Cable Tears in Arthroscopic Rotator Cuff Repairs.

PURPOSE

To determine whether anterior cable tears could be identified at the time of arthroscopic rotator cuff repair and determine the characteristics of the anterior cable tears identified.

METHODS

From 2016 to 2017 all shoulder arthroscopies had data collected prospectively at the time of surgery, specifically including injury to the capsular and tendon zones of insertion on the greater tuberosity. Anterior cable position and degree of injury and medialization were recorded, as well as complete findings of the diagnostic arthroscopy. The inclusion criterion was primary shoulder arthroscopy. The exclusion criterion was any revision shoulder arthroscopy. All arthroscopic rotator cuff repairs (ARCR) were grouped together and all other nonarthroscopic rotator cuff repair surgeries (non-ARCR) were grouped together.

RESULTS

In total, 118 shoulder arthroscopies had data collected prospectively at the time of surgery: 90 primary shoulder arthroscopies met the inclusion criteria; 28 were excluded because they were revision surgeries. There were 42 patients in the ARCR group (Group 1). Six of these were partial tears, and 36 were full-thickness tears. There were 48 patients in the non-ARCR group (Group 2). The non-ARCR Group 2 served as an anatomic baseline for ARCR Group 1. In all 90 shoulders, the rotator cable and anterior cable were identified. Group 1 (ARCR) incidence of anterior cable tears with abnormal position was 71.4% compared to 2.1% in group 2 (non-ARCR) ( < .001) Group 1 (ARCR) incidence of anterior cable tears with normal anterior cable position (n = 12) was compared to abnormal anterior cable position (n = 30). Injury to the anterior footprint capsular and tendon zones were compared. Normal anterior cable position correlated with no or low-grade injury to anterior footprint capsular zone. (Nimura zone C1). Abnormal anterior cable displacement graded as moderate (n = 20) and severe (n = 10) were compared for injury to the anterior footprint. Moderate displacement correlated with complete or high grade injury to C1 in 85% and complete injury to R1 in 45% ( < .001 and .049). In severe displacement complete C1 injury was 100%, and complete R1 injury was 100% ( < .001 and .001).

CONCLUSIONS

Anterior cable tears are universally identified in ARCR. Three patterns of medial displacement severity correlated with injury to a crucial insertion zone (C1) at the anterior footprint. The degree of anterior cable disruption at the anterior footprint and displacement was commonly disproportionately greater than the injury to the supraspinatus.

LEVEL OF EVIDENCE

Level III, diagnostic study.