Plantar pressure analysis in cadaver feet after bony procedures commonly used in the treatment of stage II posterior tibial tendon insufficiency.

BACKGROUND

Bony procedures play an essential role in the operative treatment of stage II posterior tibial tendon insufficiency and often substantially alter the loading characteristics of the foot.

METHODS

Eight matched pairs of cadaver lower extremities were axially loaded onto a TekScan HR Mat. (TekScan, Inc., South Boston, MA) After intact testing, each specimen had a lateral column lengthening (either a calcaneocuboid distraction arthrodesis [CCDA] or Evans procedure), a medializing calcaneal osteotomy (MCO), and a plantarflexion (Cotton) osteotomy of the medial cuneiform. The measured plantar pressures were divided into three forefoot regions, two midfoot regions, and two hindfoot regions. For each region, average pressure, peak pressure, and contact area data were collected.

RESULTS

Despite the fact that both lateral column lengthening procedures resulted in increased lateral forefoot pressures, no significant differences were noted between the CCDA and the Evans procedure. The addition of a MCO did not significantly alter the plantar pressures measured after the lateral column lengthening alone. Although the Cotton osteotomy resulted in increased average pressures within the medial forefoot, a compensatory significant decrease in lateral forefoot pressures was not observed.

CONCLUSIONS

The present study demonstrated increased lateral forefoot pressures after a combined lateral column lengthening and MCO and does not support the idea that a Cotton osteotomy significantly reduces loading of the lateral forefoot.

CLINICAL RELEVANCE

The incidence of lateral forefoot pain and fifth metatarsal stress fractures subsequent to either lateral column lengthening procedure may not significantly decline after a Cotton osteotomy.