SLR - May 2013 - Priscilla Zinyemba
Reference: Sinacore DR, Gutekunst DJ, Hastings MK, Strube MJ, Bohnert KL, Prior FW, Johnson JE. Neuropathic midfoot deformity: associations with ankle and subtalar joint motion. Journal of Foot and Ankle Research 2013,6:11.
Scientific Literature Review
Reviewed by: Priscilla Zinyemba, DPM
Residency Program: Temple University Hospital, Philadelphia PA
Podiatric Relevance: Neuropathic deformities impair foot and ankle joint mobility, frequently leading to abnormal stresses and impact forces. Sequelae of impaired joint motion coupled with excessive plantar stresses in individuals with diabetes mellitus and peripheral neuropathy include ulceration and infection leading to lower extremity amputation. There has been no previous report of the association of malalignment of the tarsal bones to ankle and subtalar joint mobility in neuropathic participants with or without plantar ulcerations. The impact of limited joint mobility in the ankle and subtalar joints to the onset and progression of acquired mid tarsus deformities is unknown.
Methods: Sixty participants were studied in three groups. Forty participants had diabetes mellitus and peripheral neuropathy with 20 participants having neuropathic midfoot deformity due to Charcot neuroarthropathy, and 20 participants did not have deformity. Participants with diabetes and neuropathy with and without deformity were compared to 20 young control participants without diabetes, neuropathy or deformity. Talar declination and calcaneal inclination angles were assessed on lateral view weight bearing radiographs. Ankle dorsiflexion, plantar flexion and subtalar inversion and eversion were assessed by goniometry.
Results: Talar declination angle averaged 34±9, 26±4 and 23±3 degrees in participants with deformity, without deformity and young control participants, respectively. Calcaneal inclination angle averaged 11±10, 18±9 and 21±4 degrees, respectively. Ankle plantar flexion motion averaged 23±11, 38±10 and 47±7 degrees. The association between talar declination and calcaneal inclination angles with ankle plantar flexion range of motion is strongest in participants with neuropathic midfoot deformity. Participants with talonavicular and calcaneocuboid dislocations result in the most severe restrictions in ankle joint plantar flexion and subtalar joint inversion motions.
Conclusions: Participants with diabetes mellitus, peripheral neuropathy and midfoot deformity lost more than 50 percent of ankle joint plantar flexion motion and 30 percent of subtalar joint inversion motion compared to young control participants. An increasing talar declination angle and decreasing calcaneal inclination angle is associated with decreases in ankle joint plantar flexion motion in individuals with neuropathic midfoot deformity due to calcaneo-navicular that may contribute to excessive stresses and ultimately plantar ulceration of the midfoot. The most severe restrictions in motion are observed in participants with complete talonavicular or calcaneocuboid dislocations. Goniometric assessment of ankle and subtalar joint motion and weight-bearing radiographic assessment of talar declination and calcaneal inclination angles may aid the identification of those who have midfoot deformity that may progress to plantar midfoot ulceration.