Abstract : Haglund deformity is a common cause of posterior heel pain and consists of a constellation of soft tissue and osseous abnormalities. The treatment starts with conservative approach and ends with surgical treatment in case conservative treatment fails and the symptoms are bothersome. Different surgical procedures and approaches have been used for this deformity. In this study we evaluated the clinical and functional outcome of osteotomy of the calcaneal tuberosity with debridement of the retrocalcaneal bursa and the Achilles tendon using a lateral approach at our institute. This prospective study consists of 30heels (10 men, 15 women) with mean age of 40 years who were operated at Meenakshi Medical College from March 2016 tonov 2017, with posterior heel pain, who did not respond to conservative treatment and underwent surgical decompression of the retrocalcaneal bursae and excision of bony spurs. The functional outcome was evaluated by comparing the pre and postoperative American Orthopedic Foot and Ankle Society (AOFAS) scores and Visual analog scale (VAS) score at 6th month and one year follow up. All patients were followed up for at least 12 months. AOFAS scores showed significant improvement at 6th months & one year follow up.3 out of 30 operated feet had superficial surgical site infection in the postoperative period that responded to antibiotic therapy and regular dressings. Open surgical decompressionis a safe and effective technique. We conclude lateral approach to debridement and calcaneal tuberosity resection is an effective method with good clinical and functional outcome in patients with refractory Haglund deformity.