Total hip arthroplasty in hereditary multiple exostoses with secondary osteoarthritis: A case report.

Rationale: Hereditary multiple exostoses (HME) is an autosomal dominant disease that causes multiple exostoses throughout the body. It usually occurs around the metaphysis of the long bones, and when it involves the hip, symptoms arise due to deformity and the mass effect. If the lesion does not involve the joint or is not associated with arthritis, symptoms can be relieved by surgical excision of the osteochondroma. However, if secondary osteoarthritis (OA) or subluxation of the joint has progressed, joint replacement arthroplasty should be considered.

Patient Concerns: A 57-year-old woman with HME visited our outpatient department with severe right hip pain. She complained of difficulty walking and severe discomfort during activities of daily living. She was short in stature and had a family history of HME.

Diagnosis: A physical examination revealed limited motion in the hip joint and a limb length discrepancy. Plain radiography and a computed tomography scan revealed huge osteochondromas on bilateral proximal femurs and advanced OA with subluxation of the right hip joint.

Interventions: Cementless total hip arthroplasty of the right hip joint via the modified posterolateral approach was done.

Outcomes: The patient showed good clinical scores and functional improvement at the 2-year follow-up.

Lessons: Total hip arthroplasty for an anatomically deformed joint is technically difficult, and there are many factors to consider that can make surgeons reluctant to use this modality. However, with careful preparation, arthroplasty is a good surgical option for symptomatic and functional recovery in HME patients with hip joint involvement.