Abstract:[Objective] To introduce the surgical technique and preliminary clinical effect of modified Zadek dorsal closed wedge calca-neus osteotomy for Haglund syndrome.[Methods] From May 2019 to August 2021, 12 patients received modified dorsal closed wedge calca-neal osteotomy for Haglund syndrome.The patient was placed in the healthy side lateral position, a longitudinal incision on the anterolateralside of the Achilles tendon was made to expose the insertion of the Achilles tendon.After debridement of pathology bursa, osteotomies wereconducted beginning from posterior superior calcaneal tubercle and wedging into the calcaneal body according to the preoperative design.Subsequently, the wedge- shaped bone block was removed, the wedge was closed by rotating and displacing the Achilles tendon insertionbone fragment forward and upward to correct the deformity.[Results] All the 12 patients had operation completed successfully without seri-ous complications, and followed up for 9~24 months.Compared with those before operation, the VAS score, AOFAS ankle and hindfoot scoreand Fowler-Philip angle measured on images were significantly improved at the last follow-up (P<0.05).According to Arner Lindholm crite-ria, 10 cases were excellent, 2 cases were good, with the excellent and good rate of 100% (12/12).[Conclusion] This modified Zadek dorsalclosed wedge calcaneus osteotomy for Haglund syndrome does effectively relieve heel pain, correct calcaneal tubercle retrogression deformi-ty to restore ankle function.