BACKGROUND: Depending on the direction of the subtalar joint, a foot deformity generally tends towards pronation (pes planovalgus) or supination (pes cavovarus). However, the combination of hindfoot varus and flat midfoot/forefoot (pes planovarus) is an exception to this rule. Pes planovarus has so far only been referred to in connection with Müller-Weiss disease and congenital disease. We diagnosed pes planovarus in otherwise healthy patients without these diseases.
METHODS: Forty patients with 54 symptomatic feet who were treated between August 2012 and July 2016 were included (mean age, 44.1 ± 15.7 years; 15 male/25 female). They were selected from 1064 consecutive cases (3.8%). Inclusion criteria were hindfoot varus and flat midfoot/forefoot. Their symptoms, radiographs, and therapies within the first 3 months were retrospectively analyzed. The position in the hindfoot alignment view (HAV), talometatarsal-1 angle lateral (TMT1lat) and dorsoplantar (TMT1dp), talocalcaneal angle lateral (TCAlat) and dorsoplantar (TCAdp), and calcaneal pitch angle (CPA) were measured on a DICOM/PACS system.
RESULTS: The mean radiological results (standard values from the literature in brackets) were as follows: the hindfoot was significantly in varus in the HAV (-6.9 ± 3.6 mm [-1.6 ± 7.2 mm]; P < .001), the TMT1lat was significantly flatter (-6.7 ± 5.8 degrees [8.4 ± 5.9 degrees]; P < .001), the TMT1dp was significantly less in abduction (1.5 ± 7.9 degrees [7.7 ± 8.2 degrees]; P = .005), the TCAdp showed no difference (25.9 ± 7.9 degrees [24.1 ± 5.7 degrees]; P = .118), the TCAlat was significantly larger (47.5 ± 6.1 degrees [43.4 ± 7.1 degrees]; P < .001), and the CPA was significantly flatter (17.6 ± 3.9 degrees [24.5 ± 3.0 degrees]; P < .001). The most frequent symptoms were stress-induced foot pain (n = 33), hallux valgus (n = 20), chronic ankle instability (n = 17), metatarsalgia (n = 15), chronic midfoot pain (n = 13), heel pain (n = 12), and lesser toe deformities (n = 8). Thirty-one feet were treated conservatively and 23 operatively.
CONCLUSIONS: This study showed the existence of pes planovarus without Müller-Weiss disease or congenital disease. This unusual foot form leads to difficulties if standard treatment strategies are applied, which raises the issue of the correct treatment for such patients.
METHODS: Level IV, retrospective case series.