Percutaneous CT-guided cementoplasty for stabilization of a femoral neck lesion.

Editor: Patients with chronic renal failure (CRF) face several medical complications, among them anemia, peripheral neuropathy, and hyperkalemia. Dialysis helps skirt many pathologic manifestations of CRF, but brings with it complications of its own. One complication of longstanding hemodialysis is -2-microglobulin amyloidosis (AB2M), an increasingly common complication (1). This condition is typically manifested by carpal tunnel syndrome, painful shoulder arthralgia, and hip pain. Radiographically it manifests as lucencies, erosions, and soft tissue swelling. Progression of AB2M is influenced most strongly by dialysis duration, but is also affected by age, renal transplantation failure, hyperparathyroidism, and the amount of soft tissue swelling. The authors report herein the case of a patient on longstanding hemodialysis who presented with right hip pain, secondary to amyloidotic bone lesions, which was relieved by percutaneous cementoplasty. A 45-year-old pediatrician on hemodialysis for 23 years for chronic renal failure secondary to focal segmental glomerulosclerosis developed a right-sided limp and subsequently bilateral hip pain, right greater than left. His right hip pain was deep in the medial groin and did not radiate. The pain was dull and achy in character but became sharp with movement and activity, and was worse at night but significantly alleviated with rest. A computed tomography (CT) scan revealed bilateral femoral head, neck, and acetabular lesions. The patient was referred to us for CT fluoroscopically guided biopsy of the right femoral neck and bone cement injection into the femoral neck cystic lesion. He agreed to undergo these procedures after a detailed discussion of the potential risks and benefits. He was placed supine on the CT table and underwent induction of general anesthesia. His right groin was prepared and draped and prophylactic antibiotics were administered. A 13-gauge M1 needle (WE Cook, Bloomington, IN) was placed into one of the cystic destructive lesions in the femoral neck and through that an Ellison 16-gauge needle to obtain a biopsy, which was sent for cytopathologic analysis. We then injected 1 mL of Osteobond (Zimmer, Warsaw, IN) bone cement into the lesion (Figure, top) to augment the femoral neck and prevent pathologic fracture. There was no change in the bone cement preparations from the standard format, as 10% opacification is adequate for visualization and control on CT. During the cement injection, we rapidly moved the table back and forth by hand. This rapid movement requires the tabletop to be undocked in what we call the “floating table technique.” We removed the needles (Figure, bottom) and the patient was reversed from general anesthesia. He was observed for several hours and discharged home on Tylenol #3 and ciprofloxacin. The biopsy showed evidence of amyloid, indicating AB2M secondary to chronic hemodialysis. At a 1-week follow-up visit, the patient noted an improvement in his pain. At his 1-year follow-up visit, he reported no problems with his right hip. Treatment for AB2M is either ineffective at reducing symptoms or requires surgery (2,3). Renal transplantation, although shown to prevent progression, does not effect regression of cystic lesions (4). Different surgical treatment options include curettage and bone grafting and osteosynthesis. Curettage and bone grafting results in a satisfactory cure (5), but carries with it risks of poor graft incorporation and infection. Osteosynthesis has seen high failure rates in amyloidotic bone (6). Percutaneous stabilization with bone cement augmentation is a relatively novel treatment for this condition that merits further consideration. It has been described in the literature to successfully treat other bone lesions, including lytic metastases to the acetabulum, pubic rami and ischial tuberosities, and vertebrae, as well as vertebral compression fractures caused by osteoporosis and vertebral hemangiomas (7).