Postoperative stiffness and adhesion formation around repaired and immobilized Achilles tenotomies are prevented using a model of heat shock protein induction.
BACKGROUND
Tendon repair and subsequent immobilization is frequently complicated by postoperative stiffness secondary to inflammation and peritendinous adhesions. Thermal preconditioning is known to reduce inflammation by inducing formation of cytoprotective heat shock proteins. This study evaluates the role of thermal preconditioning following complete division and repair of the Achilles tendon, with subsequent immobilization, mimicking the typical clinical scenario.


METHODS
Twenty-four New Zealand White rabbits were used in the study. The treatment group underwent thermal preconditioning, by elevating their core temperature to 41.5 degrees C for 20 minutes. The Achilles tendon of the hindlimb was divided and repaired 18 hours following thermal preconditioning. The animals were sacrificed following 3 weeks of immobilization. Range of movement of the ankle, tendon gliding, quantity of adhesions, and weight of repaired tendons were assessed.


RESULTS
Loss of range of movement at the ankle was significantly less in the treatment group versus controls (P = 0.02). The quantity of adhesions and weight of the repaired tendons were significantly reduced in the treatment group (P = <0.001 and P = 0.005, respectively). Tendon gliding relative to the surrounding soft tissue was also significantly improved in the treatment group (P = 0.002).


CONCLUSIONS
Preconditioned animals demonstrated a significantly better range of ankle movement, decreases in adhesion formation and in the gliding, and dimensions of tendons. Thermal preconditioning therefore has the potential to improve clinical results in tendon surgery following repair and immobilization.
Healy
Claragh
C
Department of Surgery, Education and Research Centre, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland. claraghhealy@eircom.net
Mulhall
Kevin J
KJ
Nelligan
Maurice
M
Murray
Paraic
P
Bouchier-Hayes
David
D
D000125:Achilles Tendon / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D000818:Animals; D000842:Ankle / Q000503:physiopathology; D003213:Conditioning, Psychological; D003240:Connective Tissue Diseases / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D004548:Elasticity; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature; D007103:Immobilization; D007249:Inflammation / Q000209:etiology; D009929:Organ Size; D019637:Orthopedic Procedures / Q000009:adverse effects*; D011184:Postoperative Period; D011817:Rabbits; D016059:Range of Motion, Articular; D000267:Tissue Adhesions / Q000209:etiology / Q000473:pathology / Q000517:prevention & control
D006360:Heat-Shock Proteins