Background: Little is known about the volumetric changes of grafted bone over time when using the induced membrane technique. This study investigates the volumetric changes of bone graft using serial computed tomographic (CT) scans following the induced membrane technique. Methods: Patients with critical-sized bone defects had serial CT scans after undergoing bone-grafting using the induced membrane technique. CT scans to evaluate the volume of bone graft were obtained immediately postoperatively and at 6 and 12 months. The change in the volume of bone graft was determined at 6 and 12 months postoperatively. Patient demographic characteristics, the location and composition of the bone graft, and the type of fixation construct were analyzed. Results: Forty patients met inclusion criteria. There were 27 tibiae and 13 femora with a mean size defect of 8.6 cm (range, 2.5 to 20.6 cm). Of these patients, 21 received autograft with cancellous bone graft and 19 received mixed autogenous bone with demineralized bone matrix (DBM) at a mean time of 17 weeks after the membrane formation. For the first 6 months, there was an overall osseous resorption of −9.9%. The overall graft volume from 6 to 12 months demonstrated an increase of osseous volume by +1.6%. For the entire 12-month period, there was a mean graft volume resorption of −8.3%. A correlation was found between the early volumetric changes of grafted bone and the percentage of DBM in the graft mixture. A correlation was also found between the late volumetric changes and the location of defect or the type of fixation. Conclusions: At 1 year after use of the induced membrane technique for the treatment of a critical-sized bone defect, resorption of the grafted bone averaged −8.3%. The volumetric changes were influenced by the property of the grafted bone, the fixation construct, and the location of the defect. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: /Objective: The incidence of intertrochanteric femoral fractures has rapidly increased with the extended lifespan of the elderly population. Surgery enables early ambulation by achieving anatomic reduction and stable internal fixation. However, reduction usually involves postoperative evaluation. Here, we present reliable parameters obtained from analyses of three-dimensional computed tomography images from cadavers to serve as guidelines during the reduction of intertrochanteric fractures. Methods: We included 184 three-dimensional modeling samples from cadavers placed in two standardized positions, similar to C-arm imaging. We recorded the level of the orthogonal line from the greater trochanter (GT) tip to the femoral head (GT orthogonal line [GTOL]) in the anteroposterior view and the line along the anterior femoral cortex passing through the femoral head (anterior cortical line) in the axial view. Correlations between these lines and angular alignments were statistically determined. Results: The GTOL passed above the femoral head center at mean 2.36 mm in all patients; 77.17% of such instances were in the upper second quadrant of the femoral head. The anterior cortical line passed under the femoral head center at mean 10.82 mm; 73.37% of such instances were in the inferior one-third of the femoral head. Consistent correlations were found between the GTOL and neck-shaft angle and between the anterior cortical line and anteversion. Conclusion: The GTOL and anterior cortical line passed through a constant level of the femoral head in most samples and were correlated with angular alignments. The intraoperative use of these simple imaginary lines improves the intertrochanteric fracture reduction quality.

This narrative review provides an up-to-date overview of atypical femoral fractures (AFFs), emphasizing diagnostic criteria, epidemiology, pathophysiology, risk factors, and evaluation with screening strategies. AFFs are rare but significant complications associated with prolonged bisphosphonate (BP) therapy for osteoporosis. Although the pathogenesis of AFFs has not been fully elucidated, its primary mechanism is thought to involve impaired bone remodeling, leading to unhealed microfractures that progress to stress fractures under repetitive loading. AFFs can occur in various regions of the femur, influenced by femoral geometry and the lower limb axis. Other risk factors include prolonged steroid use, arthroplasty, genetic predispositions, and metabolic bone disorders. The diagnosis of AFFs is based on criteria established by the American Society for Bone and Mineral Research. Key radiographic features include lateral cortical transverse fracture lines and localized cortical thickening, typically with minimal or no comminution on the medial cortex. Dual-energy X-ray absorptiometry for screening tests and magnetic resonance imaging as an advanced imaging modality enable the early detection of incomplete fractures. This multi-modal approach facilitates the prompt identification of prodromal cortical changes, reducing the risk of complete fractures in high-risk populations, particularly patients undergoing prolonged BP therapy.Level of Evidence: V