Case Report: Osteoid Osteoma of the Acetabulum Treated With Arthroscopy-assisted Radiofrequency Ablation

Abstract

Background Osteoid osteomas consist of a nidus surrounded by reactive sclerotic bone. The diagnosis typically is based on imaging and clinical presentation involving nocturnal pain. Removal of the lesion is essential and currently is performed mainly with image-guided, minimally invasive techniques. We describe a case involving an osteoid osteoma of the acetabular fossa, treated with arthroscopy-assisted radiofrequency ablation. Case Description A 47-year-old woman presented with a 9-month history of right groin pain and limited motion. The CT and MR images showed synovitis around the ligamentum teres and a nidus of the acetabular fossa, surrounded by sclerotic bone and protruding from the inner part of the lamina quadrilateral. Synovectomy and debridement of the ligamentum teres were performed, followed by radiofrequency ablation of the osteoid osteoma under direct arthroscopic observation of the hip, avoiding resection of the normal bone around the nidus and preserving the integrity of the quadrilateral lamina and cartilage. The patient had complete pain relief the next day with minimal morbidity and rapid functional restoration. At the 22-month clinical followup, the patient was asymptomatic, and the CT and MR images obtained 1 year after surgery showed no pathologic signs or synovitis. Literature Review Our case was the fifth such case to be treated with hip arthroscopy and the first of these to our knowledge to be treated with the arthroscopy-assisted radiofrequency ablation technique. Purposes and Clinical Relevance Arthroscopy-assisted radiofrequency ablation is a combined treatment technique that may be used for intraarticular lesions of the hip that otherwise would require a difficult approach and jeopardize damage to cartilage and bone and also treat concomitant synovitis.

Osteoid osteoma of the acetabulum successfully treated with computed tomography-guided resection and ablation using a standard electrosurgical generator: a case report

“…According to prior reports [4, 9, 10], OO in the acetabulum accounts for only 0.67 to 4.85% of all OO sites. An OO diagnosis can be confirmed by a combination of images [5]. Plain radiographs can detect an oval, radiolucent central nidus surrounded by a dense, reactive sclerotic mass, specifically for cortical lesions.…”

“…Although numerous surgical approaches to acetabulum OO have been described, including open surgical hip arthroscopy and CT-guided approaches [5, 10], optimal management for acetabular OO has not been established.…”

“…The healing rate is 76 to 100%, with a major complication rate of 0 to 5%. However, there are reports of articular cartilage damage in weight-bearing joints after CT-guided RFA: one patient experienced articular cartilage damage to the talus and another had damage to the acetabulum [5, 14]. In addition, because the system is expensive, percutaneous RFA is performed in only a few hospitals worldwide [15].…”

“…The most common sites are the subcortical shaft and metaphyses of long bones, such as the femur [3], but any other skeletal bone can be involved. The acetabulum is a rare site according to past reports, accounting for approximately 1% of OO lesions [4, 5]. The rarity of acetabular OO is a challenge to optimal management because of limited surgeon experience with therapeutic procedures.…”

Arthroscopic Excision of Acetabular Osteoid Osteoma: Computer Tomography–Guided Approach

“…During this time, however, chondral damage may occur and cause irreversible early osteoarthritis. 21,22 Open surgical excision has high success rates (88% to 100%). 23 However, this technique requires a large incision, wide dissection, and sometimes a hip dislocation, which results in considerable recovery time, as well as a risk of avascular necrosis.…”