Preoperative factors affecting footprint coverage in rotator cuff repair.

BACKGROUND: One of the goals of rotator cuff repair is to restore the torn tendon to its original insertion anatomically. However, it is sometimes difficult to restore the entire footprint.

PURPOSE: This study was undertaken to evaluate the variables affecting this repair coverage and to discern the differences in retear rate and clinical results between complete and incomplete footprint coverage in rotator cuff surgery.

STUDY DESIGN: Case series; Level of evidence, 4.

METHODS: From 2007 to 2009, a total of 85 consecutive repairs for medium-to-large rotator cuff tears were identified as having complete or incomplete coverage of their original footprints. We defined the complete footprint coverage (CC) group as patients who had >50% of their footprint covered during repair and the incomplete (IC) group as <50% of their footprint. Factors affecting the amount of footprint coverage were evaluated, and multivariable analysis was conducted to identify independent factors. To assess the final outcome according to the amount of footprint coverage, retear and clinical outcomes were compared between the CC and IC groups.

RESULTS: Fifty-seven repairs were defined in the CC group and 28 repairs in the IC group. Preoperatively, age, tear size in coronal oblique and sagittal oblique planes, Goutallier fatty infiltration, and atrophy of the supraspinatus affected the amount of footprint coverage in univariate analysis. In multivariable analysis, however, tear size in the coronal plane was the only independent factor affecting footprint coverage in rotator cuff repair. On postoperative MRI, 45.6% of the CC group had an intact tendon, 45.6% had a delaminated partial retear, and 8.8% had a full-thickness retear; in the IC group, 17.9% had an intact tendon, 60.7% had a delaminated partial retear, and 21.4% had a full-thickness retear. There was a statistically significant difference in the proportion of tendon integrity between groups (P = .028). Clinical scores and range of motion at final follow-up showed no difference between the 2 groups.

CONCLUSION: Tear size in the coronal plane was the only independent factor affecting the amount of footprint coverage. Repair quality based on retear classification was different between the 2 groups. However, both complete and incomplete footprint coverage in rotator cuff repair showed no differences in clinical scores and range of motion at short-term follow-up.