Arthroscopy - 2026-05-11 - Journal Article
Thicker Porcine Xenografts Provide Superior Biomechanical Stability Compared With Single-Layer Human Dermal Allografts in Superior Capsular Reconstruction.
Kim SH, Lee S, Seo JH, Hung V, McGarry MH, Lee TQ, Shin SJ
Topics
Key Takeaway
In a cadaveric SCR model, a 4.8 mm porcine xenograft restored superior humeral translation to near-intact levels at all abduction angles, while a 2.1 mm single-layer human dermal allograft showed persistently elevated translation at 0° and 20° (P < 0.05).
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Summary
This study compared biomechanical performance of porcine dermal xenograft (4.8 mm) versus single-layer human dermal allograft (2.1 mm) for SCR in a cadaveric massive rotator cuff tear model tested at 0°, 20°, and 40° abduction under simulated muscle loading. Xenograft SCR restored rotational ROM and superior humeral translation to near-intact levels across all angles, while allograft SCR produced persistently elevated superior translation at 0° and 20° and increased internal rotation at 20° and 40° versus intact state. Subacromial contact pressure was reduced by both grafts, but xenograft values more closely matched intact shoulders at all angles.
Key Limitation
The sequential testing design—xenograft always tested before allograft in every specimen—introduces an uncontrolled order effect that may confound the observed biomechanical differences between grafts.
Original Abstract
PURPOSE
To compare the biomechanical effectiveness of superior capsular reconstruction (SCR) using a thick porcine dermal xenograft versus a standard human dermal allograft (HDA) in restoring shoulder stability and motion in irreparable rotator cuff tears.
METHODS
Eight cadaveric shoulders were tested in four sequential conditions: intact, massive rotator cuff tear, SCR with xenograft, and SCR with single-layer HDA. Testing was performed at 0°, 20°, and 40° of glenohumeral abduction with 30° of external rotation under simulated balanced and unbalanced muscle loading conditions. Outcome measures included humeral rotational range of motion (ROM), superior humeral head translation, and subacromial contact pressure.
RESULTS
Mean graft thickness was 4.8 ± .2 mm for xenografts and 2.1 ± .1 mm for allografts (P < .001). Xenograft SCR preserved physiologic rotational ROM. In contrast, allograft SCR resulted in increased internal rotation at 20° (P = .012) and 40° of abduction (P = .001) and greater total ROM at 0° and 40° (P = .007) compared with the intact state. Massive tears significantly increased superior humeral translation at all angles (P < .05). Xenograft SCR restored translation to near-intact levels at 0° and 40°, whereas allograft SCR showed persistently elevated translation at 0° and 20° (P < .05). At all angles, superior translation was significantly lower with xenograft than allograft (P < .05). Subacromial pressure was highest in the massive tear condition (P < .001). Both grafts reduced pressure, however xenograft SCR resulted in lower values than allograft at 20° (P = .003) and closely matched intact values at all angles.
CONCLUSIONS
In a cadaveric model of irreparable rotator cuff tear, SCR using a thick porcine dermal xenograft more effectively restored shoulder biomechanics compared with a single-layer HDA. These advantages may relate to the xenograft's greater initial thickness and associated mechanical properties.
CLINICAL RELEVANCE
In SCR for irreparable rotator cuff tears, graft selection is a critical factor influencing biomechanical performances. This cadaveric study suggests that a porcine dermal xenograft with sufficient thickness may provide superior restoration of glenohumeral stability and joint mechanics compared with a commonly used single-layer HDA. These findings highlight the importance of graft thickness and mechanical integrity in optimizing SCR outcomes and may inform surgical decision-making in clinical practice.