Outcomes of Evans Versus Hintermann Calcaneal Lengthening Osteotomy for Flexible Flatfoot

Abstract

Background: Evans (E) and Hintermann (H) lateral lengthening calcaneal osteotomies (LLCOTs) are commonly used to correct flexible flatfoot deformities. Both methods are well accepted and produce good clinical results. The aim of this study was to compare the postoperative outcomes of both osteotomies. Methods: We retrospectively examined 53 patients with flatfoot deformities, who received surgery between October 2008 and March 2014. Seventeen E-LLCOT and 36 H-LLCOT procedures were performed during this time period, with a mean follow-up of 67.7 ± 20.6 and 40 ± 12.9 months, respectively. Data were collected using clinical and radiological examination, as well as clinical scores (Foot and Ankle Outcome Score [FAOS], University of California at Los Angeles [UCLA] activity score, numerical rating scale [NRS], and the Short-Form 36-item Health Survey [SF-36]) during regular follow-up. Results: For both groups of patients, the FAOS score, pain-NRS, and SF-36 improved significantly following surgery ( P < .05). The talus–second metatarsal angle, talonavicular coverage, and naviculocuneiform overlap showed significant correction ( P < .05). Postoperatively, radiographic degenerative changes were detected in the calcaneocuboid (CC) and subtalar joint in both groups of patients: 41% and 18% after E-LLCOT compared with 25% and 14% after H-LLCOT, although these changes did not have any clinical relevance ( P < .05). No secondary arthrodesis was necessary. There were no significant differences in the clinical or radiological outcome parameters when compared between the 2 groups. Conclusion: Both surgical techniques resulted in a significant improvement of clinical outcome scores and led to good radiological correction of flatfoot deformities. It appears that the CC joint develops less degenerative changes following the H-LLCOT procedure. Level of Evidence: Level III, comparative series.