1310 - Total Hip Arthroplasty in a Patient with Hereditary Spastic Paraparesis

Case Diagnosis: Hereditary spastic paraplegia (HSP) is a neurological disorder characterized by progressive lower limb weakness and spasticity due to corticospinal tract degeneration. Limited literature exists on musculoskeletal issues in HSP. This case showcases a 71-year-old male with genetically confirmed HSP-8, seen in PM&R clinic, with a unique presentation of hip osteoarthritis successfully treated with total joint replacement surgery.

Case Description: Over several years, the patient developed left leg "buckling". Concurrently, he experienced left hip pain and muscle spasms, although not always coinciding with leg instability. Physical examination revealed positive FADIR test of the left hip. He had 4/5 strength in hip and knee extensors, mildly increased tone, but these neurological findings were not severe enough to explain the leg buckling. MRI showed severe left hip osteoarthritis with labral damage and bone marrow edema, while radiographs indicated progressive osteoarthritis, avascular necrosis, and articular collapse over time. Conservative treatments, including physical therapy and intra-articular steroid injections, provided only short-term relief. Given the uncertain relationship between his hip pathology and leg instability, consideration was given to an articular nerve block for the hip. Ultimately, the patient opted for left total hip arthroplasty using an anterior approach. After inpatient rehabilitation, he displayed improved pain management and leg stability, enabling discharge home with improved mobility.

Discussions: Lower limb "buckling" is associated with osteoarthritis, but the mechanism is unclear, posing challenges in distinguishing from neurological weakness or muscle spasms, particularly in HSP. Furthermore, a paucity of literature exists on total joint replacement in osteoarthritis with HSP. This case illustrates a positive outcome in a patient with HSP following total hip replacement, resolving the buckling issue.

Conclusions: This case highlights successful total hip arthroplasty for severe hip osteoarthritis in a patient with HSP. Further research is imperative to define optimal treatment and management in this population.