Is the rabbit knee a suitable model for the human interphalangeal and metacarphophalangeal joints of the hand?

OBJECTIVES: The purpose of this study was to assess the suitability of the rabbit knee as a small joint model for the human interphalangeal and metacarphophalangeal joints of the hand. METHODS: The proximal joint surface areas of 47 middle phalanges, the proximal and distal joint surface areas of 90 proximal phalanges, and the distal joint surface areas of 42 metacarpals of various human cadavers were calculated and compared with the distal femoral and proximal tibial joint surface areas of 20 knee of 10 New Zealand white rabbits by a photogrammetric method. RESULTS: The mean joint surface area of the rabbit proximal tibia was larger than the proximal joint surface area of the middle phalanx, the distal joint surface area of the proximal phalanx, the proximal joint surface area of the proximal phalanx, and the distal joint surface area of the metacarpal. The mean joint surface area of the rabbit distal femur was larger than that of the middle phalanx, but similar to the proximal joint surface area of the proximal phalanx, and that of the distal metacarpal and distal proximal phalanx. CONCLUSION: The rabbit knee is not suitable model for the human interphalangeal and metacarphophalangeal joints of the hand. There is still a lack of an appropriate animal model for the small joints of the hand.