Treatment of ligament laxity by electrothermal shrinkage or surgical plication: a morphologic and mechanical comparison.
Capsular plication or thermal shrinkage can be used to enhance surgical joint stabilization. We compared mechanical or morphologic properties of the medial collateral ligament of the rabbit knee treated by either bipolar radiofrequency electrothermal shrinkage or surgical plication. After 12 weeks, the medial collateral ligaments were procured from treated and contralateral knees to undergo viscoelastic (creep) testing, quantitative transmission electron microscopy, and immunohistochemistry. Creep strain in thermal (1.85% +/- 0.32%) and plicated (1.92% +/- 0.36%) ligaments was almost twice that of the control group (1.04% +/- 0.15%), although there was no difference between treatment modalities. The morphologic parameters of all 3 groups were significantly different (P < .001). The thermal ligaments demonstrated predominantly small fibrils, whereas the plicated group displayed an intermediate distribution of heterogeneous fibrils, suggesting a different pattern of remodeling. Viscoelastic properties are similar after thermal shrinkage or plication, though inferior to those of intact ligaments.
Hill
Adam M
AM
Department of Musculoskeletal Surgery, Imperial College London, London, England, UK.
Jones
Ioan T
IT
Hansen
Ulrich
U
Suri
Amrita
A
Sandison
Ann
A
Moss
Jill
J
Wallace
Andrew L
AL
D000818:Animals; D001696:Biomechanical Phenomena; D017885:Collateral Ligaments / Q000601:surgery* / Q000648:ultrastructure; D004564:Electrocoagulation; D005260:Female; D007593:Joint Instability / Q000601:surgery*; D007719:Knee Joint; D046529:Microscopy, Electron, Transmission; D019637:Orthopedic Procedures / Q000379:methods; D011817:Rabbits