ISAKOS: 2019 Congress in Cancun, Mexico
ISAKOS

2019 ISAKOS Biennial Congress Paper #74

 

Biomechanical Effect of Superior Capsule Reconstruction Using a 3-mm and 6-mm Thick Acellular Dermal Patch Graft in a Dynamic Shoulder Model

Bastian Scheiderer, MD, Munich, Bavaria GERMANY
Elifho Obopilwe, ME, BSc, Farmington, CT UNITED STATES
Mark P. Cote, PT, DPT, MSCTR, Farmington, CT UNITED STATES
Florian B. Imhoff, MD, Priv.-Doz., Zurich SWITZERLAND
Felix Dyrna, MD, M√ľnster GERMANY
Knut Beitzel, MD, MA, Cologne GERMANY
Andreas B. Imhoff, MD, Prof., Munich, Bavaria GERMANY
Augustus D. Mazzocca, MS, MD, Farmington, CT UNITED STATES
Daichi Morikawa, MD, PhD, Tokyo JAPAN

Department of Orthopaedic Surgery, University of Connecticut, Farmington, CT, UNITED STATES

FDA Status Cleared

Summary

In a dynamic cadaveric shoulder model, SCR using a 6-mm thick acellular dermal allograft demonstrated superior glenohumeral stability results compared to a 3-mm thick acellular dermal allograft.

Abstract

Purpose

To evaluate the effect of superior capsule reconstruction (SCR) with a 3-mm and 6-mm thick acellular dermal allograft on shoulder biomechanics.

Methods

Eight fresh-frozen cadaveric shoulders were tested using a dynamic shoulder testing system. Maximum abduction angle (MAA), glenohumeral superior translation (ghST), subacromial peak contact pressure (sPCP) and cumulative deltoid force (cDF) were compared among 4 conditions: (1) intact shoulder, (2) simulated irreparable rotator cuff tear (RCT), (3) SCR using a 3-mm thick acellular dermal allograft, (4) SCR using a 6-mm thick acellular dermal allograft.

Results

A simulated irreparable RCT significantly decreased the MAA compared to the intact rotator cuff state (73% of intact; P < .001); significantly increased ghST (204% of intact; P = .001), sPCP (200% of intact; P < .001) and cDF (158% of intact; P < .001). SCR with a 3-mm thick patch significantly increased MAA (88% of intact; P = .01) and decreased ghST (138% of intact; P = .01) compared to the RCT state, but not sPCP (188% of intact) and cDF (141% of intact). SCR with a 6-mm thick patch significantly increased the MAA compared to the torn state (95% of intact; P < .001) and significantly decreased ghST (77% of intact; P < .001), sPCP (132% of intact; P < .001) and cDF (117% of intact; P = .001). There was no statistical difference in the MAA, ghST, sPCP and cDF when comparing SCR with a 6-mm thick patch to the intact rotator cuff state. GhST (P = .03), sPCP (P < .001) and cDF (P = .02) were significantly different when comparing SCR using a 3-mm thick patch to a 6-mm thick patch; MAA showed no difference.

Conclusion

SCR with a 3-mm thick acellular dermal allograft improved MAA and ghST in a simulated RCT. Moreover, SCR with a 6-mm thick graft instead of 3-mm thick graft decreased sPCP and cDF.

Clinical Relevance: SCR with a 6-mm thick acellular dermal allograft attached at 45° of shoulder abduction restores superior glenohumeral stability.