ORIGINAL ARTICLES   

Minerva Ortopedica e Traumatologica 2001 December;52(6):251-60

Copyright © 2001 EDIZIONI MINERVA MEDICA

language: Italian

Tarsal synostosis. Diagnosis, treatment and personal experience

Del Din R., Castoldi F., Marmotti A., Germano M., Bertino R.

Background. The authors report a retrospective study aimed at evaluating the importance of clinical, anatomic and radiological characteristics in the choice of treatment for tarsal synostosis.
Methods. Between 1994 and 2001 seven cases of synostosis were treated: two complete calcaneoastragalar forms, four incomplete calcaneoastragalar forms and one complete calcaneal scaphoid synostosis. Each synostosis was evaluated clinically and radiographically; CAT was used to identify the site, the percentage of the articular area involved, the axial deviation and the presence of arthrosic signs secondary to the pathology. CAT was not only the best diagnostic instrument, but also a useful means for the postoperative evaluation of results. Five cases were initially treated conservatively for a mean period of 6.5 years; 4 of these cases then underwent surgery owing to persistent painful symptoms. The other two cases underwent surgery immediately owing to the disabling nature of pain at the back of the foot. Two cases of calcaneoastragalar synostosis underwent simple resection, whereas isolated arthrodesis of the subastragalar joint was chosen in the other three calcaneoastragalar synostoses and in the calcaneal scaphoid form.
Results. The joint classification system drawn up by Michael S. Downey proved a very useful guide when establishing the indications for surgery owing to the variable presentation of the pathology. Follow-up lasted for 7 years in four patients, 2 years in one patient and 1 year in one case; the patients were assessed using the numerical system of the ''American Orthopae-dic Foot and Ankle Society'' (AOFAS), obtaining scores between 70 and 90 in six cases, which confirmed the very satisfactory nature of results; only one patient had an inadequate score (52). The results of the study show that the simple resection of synostosis is indicated in patients who still have to complete their skeletal growth, with slight arthrosis of the subastragalar joint and articular involvement of half of the inferior synostosis.
Conclusions. Arthrodesis is indicated in patients with skeletal maturity, significant signs of degeneration, severe axial deviation and articular involvement of over half of the synostosis.