Effects of a surface matching articular resurfacing device on tibiofemoral contact pressure: results from continuous dynamic flexion–extension cycles
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The application of a defect-size metal implant for the treatment of focal articular cartilage lesions of the femoral condyle is of potential concern resulting in cartilage damage to opposing biological structures. This in vitro study aims to determine the tibiofemoral contact pressure with a contoured articular partial femoral resurfacing device under continuous dynamic pressure loads.
Peak and area contact pressures were determined in eight fresh-frozen cadaveric specimens using a pressure-sensitive sensor placed in the medial compartment above the menisci. All knees were tested in the untreated condition and after implantation of the prosthetic device in the weight-bearing area of the medial femoral condyle. A robotic knee simulator was used to test each knee under continuous pressure load for 400 s during 40 dynamic knee bending cycles (5°–45° flexion) with body weight ground reaction force (GRF). The GRF was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles.
Comparison of the untreated condition to focal inlay resurfacing showed no statistically significant differences (P ≤ 0.05) between all testing conditions. The average maximum peak contact pressure across all 40 flexion cycles increased by 5.1% after resurfacing compared to the untreated knees. The average area contact pressure essentially stayed the same (+0.9%).
The data suggest that resurfacing with the contoured articular prosthetic device does not pose any immediate deleterious effects to the opposing surfaces based on peak and area contact pressure in a continuous dynamic in vitro application. However, long-term in vivo effects remain to be evaluated.
KeywordsKnee Articular cartilage defect Tibiofemoral joint Articular prosthetic device Contact pressure Dynamic loading
- 12.Custers RJ, Saris DB, Dhert WJ, Verbout AJ, van Rijen MH, Mastbergen SC, Lafeber FP, Creemers LB (2009) Articular cartilage degeneration following the treatment of focal cartilage defects with ceramic metal implants and compared with microfracture. J Bone Joint Surg Am 91:900–910CrossRefPubMedGoogle Scholar
- 15.Hangody L, Fules P (2003) Autologous osteochondral mosaicplasty for the treatment of full-thickness defects of weight-bearing joints: ten years of experimental and clinical experience. J Bone Joint Surg Am A 85(Suppl 2):25–32Google Scholar
- 20.Kirker-Head CA, Van Sickle DC, Ek SW, McCool JC (2006) Safety of, and biological and functional response to, a novel metallic implant for the management of focal full-thickness cartilage defects: preliminary assessment in an animal model out to 1 year. J Orthop Res 24:1095–1108CrossRefPubMedGoogle Scholar
- 30.von Skrbensky G, Huber R (2006) Vienna 2.2 knee joint simulator for long-term in vitro testing. J Biomech 39:S50Google Scholar