Objective To investigate the effectiveness of calcaneal V-shaped osteotomy combined with subtalar arthrodesis in the treatment of Stephens Ⅱand Ⅲ calcaneal fracture malunion. MethodsThe clinical data of 24 patients with severe calcaneal fracture malunion treated by calcaneal V-shaped osteotomy combined with subtalar arthrodesis between January 2017 and December 2021 were retrospectively analyzed. There were 20 males and 4 females with an average age of 42.8 years (range, 33-60 years). Conservative treatment of calcaneal fracture failed in 19 cases and operation failed in 5 cases. Stephens classification of calcaneal fracture malunion was type Ⅱ in 14 cases, and type Ⅲ in 10 cases. Preoperative Böhler angle of calcaneus was 4.0°-13.5° (mean, 8.6°), Gissane angle was 100°-152° (mean, 119.3°). The time from injury to operation was 6-14 months (mean, 9.7 months). American Orthopedic Foot and Ankle Society (AOFAS) ankle and hindfoot score and visual analogue scale (VAS) score were used to evaluate the effectiveness before operation and at last follow-up. Bone healing was observed and the healing time was recorded. The talocalcaneal height, talus inclination angle, Pitch angle, calcaneal width, and hindfoot alignment angle were measured. Results Necrosis of the cuticle edge of the incision occurred in 3 cases, which were cured by dressing change and oral administration of antibiotic therapy. The other incisions healed by first intention. All the 24 patients were followed up 12-23 months, with an average of 17.1 months. The foot shape of the patients recovered well, the shoes were restored to the size before injury, and there was no anterior ankle impingement. Bone union was achieved in all patients, and the healing time ranged from 12 to 18 weeks, with an average of 14.1 weeks. At last follow-up, no adjacent joint degeneration occurred in all patients; 5 patients had mild foot pain during walking, which had no significant impact on daily life and work; no patient needed revision surgery. The AOFAS ankle and hindfoot score was significantly higher than that before operation (P<0.001), the results were excellent in 16 cases, good in 4 cases, and poor in 4 cases, and the excellent and good rate was 83.3%. The VAS score, talocalcaneal height, talus inclination angle, Pitch angle, calcaneal width, and hindfoot alignment angle were significantly improved after operation (P<0.001). ConclusionCalcaneal V-shaped osteotomy combined with subtalar arthrodesis can effectively relieve hindfoot pain, correct talocalcaneal height, restore talus inclination angle, and reduce the risk of nonunion after subtalar arthrodesis.