SHALLOW TROCHLEA AND FEMOROPATELLAR OSTEO ARTHRITIS

Introduction The high frequency of femoro-patellar syndrome encountere d in Libreville (Gabon) and its association with shallow trochlea and important cartilaginous lesions in our surgical cases urged us to inve stigate the role of this dysplasia as a cause of femoro-patellar osteo arthitis. Material and methods Our study consisted of two series: - a retrospective study: 50 patients operated for complications of femoro- patellar syndrome. - a prospective study: we analysed the trochlea mor phology of 100 healthy Gabonese. Results In our operated cases, we not ed a high frequency of shallow trochlea (61 per cent) with important c artilaginous lesions (64 per cent of femoro-patellar osteoarthitis). I n the prospective study, we noted 89 per cent of shallow trochlea. The average trochlea angle was 126-degrees. Discussion The review of the operated patients showed important cartilaginous lesions associated wi th a ''closed angle trochlea'', confirming the observations of Buard a nd coll., and showing that this dysplasia can be a cause of femoro-pat ellar osteoarthitis. The prospective study found 89 per cent of shallo w trochlea, which is higher to that seen in Europe (19 per cent for Bu ard and Coll.) and may pose the problem of an anatomic predisposition of osteoarthitis in the Central African patients. Conclusion The shall ow trochlea is a dysplasia often encountered in Central Africa. It is associated with important cartilaginous lesions. The shallow trochlea seems to be a favourable factor to femoro-patellar osteoarthitis.