[Case Report]Parkinson's disease and spinal long fusion in a patient who required bilateral revision surgery for irreducible dislocation of total hip arthroplasties in rapidly destructive coxarthropathy: a case report

[ABSTRACT]【Background】 For patients with Parkinson's disease, it is difficult to treat hip joint disorders because of postural abnormalities and muscle rigidity. Advances in spine surgery have led to an increase in the use of long-range fusion procedures, and their impact on pelvic alignment has been gaining attention. We report the case of a patient with Parkinson's disease and spinal long fusion who required bilateral revision surgery for irreducible dislocation of total hip arthroplasties in rapidly destructive coxarthropathy.【Case report】 A woman with severe Parkinson's disease underwent spinal long-range fusion from Th3 to S for spinal deformity and lumbar spinal canal stenosis at 71 years of age. Three years later she developed severe right hip pain and difficulty walking due to progressive narrowing of the joint space due to posterior pelvic tilt (right Japanese Orthopaedic Association (JOA) score 21). The patient underwent right total hip arthroplasty via a direct anterior approach while supine on a traction table. Although the implant alignment was in a safe zone and intraoperative muscle tension was stable, the patient dislocated the hip anteriorly on the fourth postoperative day when transferring from a wheelchair to a bed. Manual reduction under general anesthesia was attempted but failed because of the muscle rigidity. Revision surgery was required on the seventh day after the initial surgery. She was able to walk with a cane and was dischargedfrom the hospital. However, 6 months later, the contralateral left hip became painful and she needed a wheelchair again（left JOA score 19）. By her strong request, we performed left total hip arthroplasty. However, one week after the surgery, she felt discomfort in her left hip joint when she was going to sit on the toilet, which caused the stem to sink and posterior twisting. Two days later, when she tried to put on her shoes, she dislocated posteriorly with a periprosthetic fracture. Revision surgery was required 2 weeks later. The patient was discharged home 2 months postoperatively and was able to walk alone 3 months postoperatively. Five years after surgery, both hips have recovered to the point where she can walk alone without pain and without redislocation, and she is highly satisfied with the outcome (JOA score: right 68, left 63). 【Conclusion】Dislocation can occur even with appropriate implant placement. This is because the pelvic alignment changes with posture such as lying down, standing, and sitting. Especially in patients with spinal long fusion, immobility decreases and implant impingement is easy, and dislocation can occur both anteriorly and posteriorly. Additionally, in Parkinson’s disease, not only is it difficult to reduce intraoperatively due to muscle rigidity, but manual reduction is also difficult if the patient dislocates their hip after surgery, and open reduction may be necessary. Although the artificial hip joint of Parkinson’s disease is intractable, patient satisfaction is high.