Purpose of the study: In 1966, R. Merle d'Aubigné published 4 cases of unicondylar destructions (due to trauma or tumor) reconstructed with the patella replacing the joint surface. Since this time the same technique has been used in 6 other cases. The results of these 10 patients are studied.
Material and method: Six of the examined patients were treated initially for a giant cell tumor, 1 for a low-grade osteosarcoma, and 3 for post traumatic arthritis. The patellar transplant remains vascularized by it's supero-medial vascular bundle. The femoral condyle was affected in 9 cases, the tibial plateau in one.
Results: The long term follow-up of these 10 patients revealed unexpected satisfactory results. None of the operated knees was clinically "excellent", due to instability or axial deterioration, but function remained correct, with a good range of motion, active professional possibilities, and, often, regular practice of some sports, like skiing or tracking. Function was not correlated with radiological aspect. The arthritic remodeling of the knee was obvious in all of the cases, and regularly increasing. Five of the 10 knees had to be reoperated (one or several times): 3 during the first months of follow-up (1 for sepsis, 2 for supracondylar fractures), 5 during the first years, to improve function (2 arthrolysis, 2 valgus osteotomies, 1 loose bodies removal). Three patellar plasties had to be converted into a total knee prosthesis, after 8, 27 and 40 years. The follow-up of the 7 patients still walking on their patellar plasty is of 2, 4, 17, 19, 24, 24 and 25 years.
Discussion and conclusion: Condylar reconstruction using a vascularized patellar transplant is mechanically speaking an approximative, obsolete and rather rough procedure. Nowadays one would prefer a knee prosthesis, with or without auto or allografts, preserving the patella. The immediate functional result would certainly be better, but the future remains uncertain. The patellar plasty can delay for 10, 20 years or even more the time of a prosthesis. This technique might also be useful in countries where prosthetic implants are not easily available.