Effective Treatment for Breakage of a Solid Long Cementless Stem with a Distal Locking Screw: A Case Report

INTRODUCTION: Fractures around the femoral stem are difficult complications to treat. In revision surgery, good results can be obtained by a long cementless stem with a distal locking screw. However, there are few reports of treatment for cases where the stem itself is broken. CASE REPORT: The case of a 69-year-old woman in which the femoral stem that was broken 5 years after performing revision surgery for a right periprosthetic femoral fracture was repaired using a solid long stem with a distal locking screw is presented. Her past history included osteoporosis and rheumatoid arthritis. She fell due to sudden right thigh pain and was then taken to the emergency department of our hospital. X-ray examination showed breakage of the stem itself at the position of the distal locking screw hole closest to the previous fracture. Revision total hip arthroplasty using a larger diameter stem of the same model was performed. The previous fracture site had been a fibrous non-union, and the femur proximal to the previous fracture site had severe atrophy and bone loss due to stress shielding. Two years after surgery, the patient can walk without pain, and progression of stress shielding, loosening of the stem, and breakage of the implants have not occurred. CONCLUSION: In the present case, non-union, proximal bone atrophy, the location of the hole of the distal locking screw, and insufficient stem strength were the causes of stem breakage. It is necessary to take measures such as bone grafting and select a stem as long as possible for the position of the distal locking screw to be as far as possible from the fracture line when using a narrow long stem with a distal locking screw.