[Ankle arthrodesis for congenital absence of the fibula].
OBJECTIVE
Bilateral congenital absence of the fibula in a 10-year-old boy. A marked valgus malalignment at the left ankle and a foot with three rays caused pain during standing and walking. Ortheses did not help. Therefore, various treatment options were considered such as amputation of the foot, a supramalleolar correction osteotomy, and a tibiotalar arthrodesis.


METHODS
Correction of malalignment and ankle arthrodesis stabilized with an external mini-fixator while sparing the distal tibial physis.


METHODS
Two skin incisions: one on the medial side visualizing the flexor tendons and the neurovascular bundle while sparing the sural nerve and the small saphenous vein. Exposure of the medial malleolus after division of its ligamentous and capsular attachments. Localization of the ankle joint. The second incision on the lateral side. Z-lengthening of the sole peroneal tendon. Opening of the ankle joint at the lateral and anterior aspect. Resection of the articular surfaces of tibia and talus based on a preoperatively made drawing that showed an alignment of the hindfoot with the longitudinal axis of the tibia and the foot in 90 degrees in relation to the leg. Temporary insertion of a Kirschner wire from the sole of the foot into the tibia to maintain the obtained correction. Placement of a mini-fixator: one threaded Kirschner wire crosses the talocalcaneal synostosis, the second the distal tibial epiphysis, and the third one the proximal third of the tibia. Once the frame is mounted, compression of the resection surfaces and slight distraction between the proximal and middle Kirschner wires.


RESULTS
At the age of 16 years the boy is able to use a regular shoe with an orthotic insert; he is pain-free and can participate in all daily activities. The growth of the tibia has not been affected.
Exner
G Ulrich
GU
Leitender Arzt der Abteilungen für Tumororthopädie und Kinderorthopädie, Universitätsklinik Balgrist, Forchstrasse 340, CH-8008 Zürich, Switzerland.
D000843:Ankle Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D018771:Arthralgia / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control*; D001174:Arthrodesis / Q000295:instrumentation* / Q000379:methods*; D001863:Bone Screws; D001864:Bone Wires; D002648:Child; D005360:Fibula / Q000000981:diagnostic imaging / Q000601:surgery*; D005532:Foot Deformities, Congenital / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D008297:Male; D011859:Radiography; D020127:Recovery of Function; D016896:Treatment Outcome