Leg length discrepancy is not an uncommon result of total hip arthroplasty and a major cause of patient dissatisfaction. Spinopelvic obliquity is a less-recognized cause of limb length differences in patients undergoing total hip arthroplasty. The robotic arm has recently been introduced to enhance implant positioning during surgery and to achieve more predictable leg length and offset goals. In this article, we illustrate the case of a patient who presented with a leg length discrepancy associated with significant spinopelvic obliquity. We show the use of the robotic arm total hip application to improve her pelvic obliquity and limb length discrepancy. This approach helped with the patient's symptoms and gait as well as her radiographic pelvic alignment.

Introduction: The objective of this study is to comprehensively evaluate fracture type, category of nonunion, and metabolic profile to identify metabolic causes that may impact fracture union. Methods: A retrospective chart review of patients diagnosed with nonunion after fracture fixation was performed. Patient demographics, fracture characteristics, and metabolic profiles were assessed. Results: Data was collected from 94 patients with nonunion, with a mean age of 54.7 years, 50% men, 47.3% obese, and 60.8% current/former smokers. The most common nonunited bone was the femur (48%), tibia (22%), humerus (15%), ulna (5%), clavicle (3%), and fibula (2%). The distal femur, femoral shaft, and tibial shaft made up 50% of the nonunion. The intra-articular fracture was diagnosed in 13% and open injuries in 27%. The most common metabolic abnormalities were low hemoglobin (62.3%), elevated neutrophil percentage (61.9%), elevated erythrocyte sedimentation rate in women (51.8%), low testosterone (46.9%), and hypovitaminosis D (44.3%). Conclusion: The prevalence of metabolic abnormalities was documented across all nonunion types, suggesting this is not unique to atrophic nonunion. Given the high morbidity and cost of nonunion, and low cost of vitamin supplementation, future prospective studies are warranted to identify effective prevention and treatment.