BACKGROUND: Surgical hip dislocation enables complete exposure of the hip joint for treatment of various hip disorders.There is limited information regarding the complications associated with this procedure. Our purpose is to report the incidence of complications associated with surgical dislocation of the hip in a large, multicenter patient cohort. METHODS: A retrospective, multicenter analysis of patients who had undergone surgical hip dislocation was performed.Patients who had undergone a simultaneous osteotomy were excluded. Complications were recorded, with specific assessment for osteonecrosis, trochanteric nonunion, femoral neck fracture, nerve injury, heterotopic ossification, and thromboembolic disease. We graded complications with a validated classification scheme that includes five grades based on the treatment required to manage the complication and any long-term morbidity. With this classification, a Grade-I complication is one that requires no change in the routine postoperative course, Grade II requires a change in outpatient management, Grade III requires invasive surgical or radiologic management, Grade IV is associated with long-term morbidity or is life-threatening,and Grade V results in death. RESULTS: The study included 334 hips in 302 patients seen at eight different North American centers. There were eighteen complications (5.4%) that were classified as Grade I (not clinically relevant and required no deviation from routine postoperative care). There were six complications (1.8%) classified as Grade II (treated on an outpatient basis or with close observation and resolved). There were nine complications (2.7%) classified as Grade III (treatable and resolved with surgery or inpatient management). There was one complication (0.3%) classified as Grade IV (resulting in a long-term deficit). A total of thirty hips had one or more complications, for an overall incidence of 9%. Excluding heterotopic ossification, the complication rate was sixteen (4.8%) of 334. CONCLUSIONS: Surgical hip dislocation is a safe procedure with a low complication rate. Many of the complications were clinically unimportant heterotopic ossification. There were no cases of femoral head osteonecrosis or femoral neck fracture, and, with the exception of one sciatic neurapraxia that partially resolved, no other complication resulted in long-term morbidity.