RECONSTRUCTION OPERATIONS FOR ACQUIRED FLATFOOT - BIOMECHANICAL EVALUATION

A major limitation of operations commonly performed for acquired flatf oot is inadequate correction of alignment. The authors defined the eff icacy of two operations, deltoid ligament reconstruction and flexor di gitorum longus tendon transfer, for treatment of posterior tibial tend on dysfunction with flatfoot deformity, Twelve fresh-frozen foot speci mens were used, A flatfoot deformity was created, and, to simulate the midstance phase of gait, loads were applied axially to the plantar su rface of the foot and to appropriate tendons, Foot position improved s ubstantially after deltoid ligament reconstruction but not after flexo r digitorum longus tendon transfer. The average increase in arch heigh t after deltoid ligament reconstruction was 10.3 +/- 8.9 mm and after flexor digitorum longus tendon transfer, -0.6 +/- 2.0 mm, Mean arch he ight after deltoid ligament reconstruction was 2.2 +/- 1.7 mm less tha n intact arch height and, after flexor digitorum longus tendon transfe r, 13.2 +/- 9.0 mm less than intact arch height, Improvement in metata rsal-talar, calcaneal-talar, and talar-tibial positions was significan tly greater after deltoid ligament reconstruction than after flexor di gitorum longus tendon transfer. Although the authors do not advocate c linical use, the deltoid ligament reconstruction was more effective th an flexor digitorum longus tendon transfer in restoring arch alignment in flatfoot.