BACKGROUND: Success of superior capsule reconstruction (SCR) using both fascia lata (FL) and human acellular dermal allograft (ACD) grafts have been reported. One possible explanation for a discrepancy in outcomes may be attributed to graft thickness. SCR with commercially available 3mm thickness ACD is not biomechanically equivalent to FL. Our hypothesis was that SCR with single 6mm thickness ACD allograft will restore Subacromial space distance (SubDist), and peak subacromial contact pressures (PSCP) to intact shoulder and will be comparable to SCR with 8mm FL. METHODS: Eight cadaveric shoulders were tested in 4 conditions: intact; irreparable supraspinatus Tear (SST); SCR FL allograft (8mm thickness); and SCR single ACD allograft (6mm thickness). SubDist, and PSCP were measured at 0°, 30°, 60° of glenohumeral abduction in the scapular plane. Parameters were compared using a repeated-measures analysis of variance with Tukey post hoc test, and graft dimensions were compared using a Student t-test. RESULTS: SST had decreased SubDist (p<0.05) and increased PSCP (p<0.05) compared with intact. At all angles, the SCR ACD demonstrated increased SubDist compared to tear condition (p<0.001) with no difference between grafts. Furthermore, there was decreased PSCP after both ACD and FL SCR compared to intact condition with no difference between grafts at 0° (p=0.006, p=0.028) and 60° abduction (p=0.026, p=0.013). Both ACD and FL elongated during testing. CONCLUSIONS: Our results suggest SCR with a single 6mm thickness ACD is non-inferior to FL regarding SubDist and PSCP while completely restoring the superior stability of the glenohumeral joint compared to intact.
BACKGROUND: Success of superior capsule reconstruction (SCR) using both fascia lata (FL) and human acellular dermal allograft (ACD) grafts have been reported. One possible explanation for a discrepancy in outcomes may be attributed to graft thickness. SCR with commercially available 3mm thickness ACD is not biomechanically equivalent to FL. Our hypothesis was that SCR with single 6mm thickness ACD allograft will restore Subacromial space distance (SubDist), and peak subacromial contact pressures (PSCP) to intact shoulder and will be comparable to SCR with 8mm FL. METHODS: Eight cadaveric shoulders were tested in 4 conditions: intact; irreparable supraspinatus Tear (SST); SCR FL allograft (8mm thickness); and SCR single ACD allograft (6mm thickness). SubDist, and PSCP were measured at 0°, 30°, 60° of glenohumeral abduction in the scapular plane. Parameters were compared using a repeated-measures analysis of variance with Tukey post hoc test, and graft dimensions were compared using a Student t-test. RESULTS: SST had decreased SubDist (p<0.05) and increased PSCP (p<0.05) compared with intact. At all angles, the SCR ACD demonstrated increased SubDist compared to tear condition (p<0.001) with no difference between grafts. Furthermore, there was decreased PSCP after both ACD and FL SCR compared to intact condition with no difference between grafts at 0° (p=0.006, p=0.028) and 60° abduction (p=0.026, p=0.013). Both ACD and FL elongated during testing. CONCLUSIONS: Our results suggest SCR with a single 6mm thickness ACD is non-inferior to FL regarding SubDist and PSCP while completely restoring the superior stability of the glenohumeral joint compared to intact.
Keywords:
Superior capsule reconstruction; biomechanics; cadaver study; fascia lata; human acellular dermal allograft; subacromial contact pressure; superior translation
Authors: Julianne M Forlizzi; Stephen M Sylvia; Robert J Pettit; Sundeep S Saini; Meghan MacAskill; Glen Ross; Sarav S Shah Journal: Arthrosc Tech Date: 2021-06-19