Db. Thordarson et al., EFFECT OF CALCANEAL OSTEOTOMY AND PLANTAR FASCIOTOMY ON ARCH CONFIGURATION IN A FLATFOOT MODEL, Foot & ankle international, 19(6), 1998, pp. 374-378
Seven fresh-frozen cadaver specimens had a calcaneal osteotomy perform
ed obliquely through the posterior portion of the calcaneus. Angular r
elationships between the first metatarsal and talus were recorded with
the use of a motion-analysis system in the transverse, sagittal, and
coronal planes. The specimen was mounted in a testing machine and load
ed via an intramedullary rod to 150, 350, and 550 N. A flatfoot model
was created, and repeat measurements were obtained. The calcaneal oste
otomy was then displaced 1 cm medially, and repeat measurements were m
ade at each of the three load levels. The calcaneal osteotomy was then
returned to its original position, the plantar fascia was divided, an
d the new angular measurements were obtained. The calcaneal osteotomy
was again displaced 1 cm, and repeat angular measurements were obtaine
d. A mild consistent flatfoot deformity was created in all three axes
before the plantar fascia was cut. A statistically significant increas
e in deformity was noted after cutting the plantar fascia. A correctio
n of the flatfoot deformity in all three planes occurred with the medi
al displacement of the calcaneal osteotomy, which was greater at the l
ower load levels. We noted that a medial displacement calcaneal osteot
omy partially corrected a flatfoot deformity in all three planes. The
correction occurred with or without an intact plantar fascia and, ther
efore, is independent of the structure. We also noted an increased def
ormity after dividing the plantar fascia. This study provides some bio
mechanical insight as to the corrective effect of a medial displacemen
t calcaneal osteotomy in correcting a flatfoot deformity.