TY - JOUR
T1 - Complete removal of load is detrimental to rotator cuff healing
AU - Galatz, Leesa M.
AU - Charlton, Nichole
AU - Das, Rosalina
AU - Kim, H. Mike
AU - Havlioglu, Necat
AU - Thomopoulos, Stavros
N1 - Funding Information:
This study was funded by an Orthopedic Research and Education Foundation Career Development Award and by a Research Award from American Shoulder and Elbow Surgeons.
PY - 2009/9
Y1 - 2009/9
N2 - Hypothesis: This study evaluated the effect of the mechanical environment on the healing rotator cuff by paralyzing the supraspinatus muscle in the operative shoulder of a rat model of rotator cuff injury and repair. Methods: Unilateral shoulders of rats underwent a supraspinatus injury and repair. Botulinum toxin A was used to paralyze the muscle after repair. Postoperatively, 1 group was immobilized and 1 group was allowed free range of motion. Saline-injected, casted rats were used as the control group. Repairs were evaluated histologically, geometrically, and biomechanically. Results: Specimens from the saline-injected rats had greater scar volume and cross-sectional area of the repair compared with the paralyzed groups. Structural properties were increased in the saline group compared with the paralyzed groups. Free range of motion (ie, uncasted group) resulted in modest improvements in biomechanical properties but did not obviate the effect of paralysis. Conclusions: Complete removal of load was detrimental to rotator cuff healing, especially when combined with immobilization. Level of evidence: Basic science study.
AB - Hypothesis: This study evaluated the effect of the mechanical environment on the healing rotator cuff by paralyzing the supraspinatus muscle in the operative shoulder of a rat model of rotator cuff injury and repair. Methods: Unilateral shoulders of rats underwent a supraspinatus injury and repair. Botulinum toxin A was used to paralyze the muscle after repair. Postoperatively, 1 group was immobilized and 1 group was allowed free range of motion. Saline-injected, casted rats were used as the control group. Repairs were evaluated histologically, geometrically, and biomechanically. Results: Specimens from the saline-injected rats had greater scar volume and cross-sectional area of the repair compared with the paralyzed groups. Structural properties were increased in the saline group compared with the paralyzed groups. Free range of motion (ie, uncasted group) resulted in modest improvements in biomechanical properties but did not obviate the effect of paralysis. Conclusions: Complete removal of load was detrimental to rotator cuff healing, especially when combined with immobilization. Level of evidence: Basic science study.
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U2 - 10.1016/j.jse.2009.02.016
DO - 10.1016/j.jse.2009.02.016
M3 - Article
C2 - 19427237
AN - SCOPUS:68749115061
SN - 1058-2746
VL - 18
SP - 669
EP - 675
JO - Journal of Shoulder and Elbow Surgery
JF - Journal of Shoulder and Elbow Surgery
IS - 5
ER -