Hemiarthroplasty with a long femoral stem and proximal cement augmentation for a myeloma-related pathological femoral neck fracture: a case report

Background Pathological femoral neck fractures are a frequent skeletal complication of multiple myeloma due to extensive osteolytic bone destruction. However, extensive proximal femoral invasion with massive cavitary destruction leading to femoral neck fracture is clinically uncommon, and optimal surgical management remains challenging because of poor bone quality and high mechanical failure risk. Case presentation We report a patient with a known history of multiple myeloma who sustained a low-energy fall resulting in a pathological fracture of the right femoral neck. Imaging demonstrated diffuse osteolytic involvement of the pelvis and proximal femur with severe osteoporosis and degenerative hip changes. Given the patient's poor general condition and multiple comorbidities, a multidisciplinary team (MDT) discussion involving orthopaedics, hematology, cardiology, endocrinology, and neurology was conducted to formulate an individualized perioperative strategy. Bipolar hemiarthroplasty was performed using a long femoral stem with distal press-fit fixation, combined with debridement of tumor-infiltrated tissue, proximal cement augmentation of osteolytic bone defects, and supplemental plate and cerclage cable fixation. This reconstructive strategy was selected as an alternative to proximal femoral replacement to achieve immediate mechanical stability and facilitate early mobilization. Intraoperative autologous blood salvage and reinfusion were used as part of the perioperative blood-management strategy, with no immediate procedure-related complications observed. Results The patient was followed for 15 months after surgery. At the latest follow-up, she remained ambulatory with satisfactory hip function and a Harris Hip Score of 84 points. Follow-up radiographs demonstrated stable reconstruction without prosthetic loosening, dislocation, periprosthetic fracture, or other major implant-related complications. Conclusion Hemiarthroplasty with a long femoral stem, proximal cement augmentation, and supplemental fixation may represent a viable option for selected patients with multiple myeloma-related pathological femoral neck fractures and extensive osteolytic destruction. Careful assessment of bone loss and individualized multidisciplinary planning are important for balancing mechanical stability and perioperative risk.