Pelvis Insufficiency Fracture after Total Knee Arthroplasty

Abstract

Pelvic insuffi ciency fracture is a very rare complication after total knee arthroplasty (TKA). This fracture occurs in elderly osteoporotic patients, spontaneously or after minor trauma, and its diagnosis can be diffi cult unless there is a high degree of clinical sus picion. The consequence of missed pelvic insuffi ciency fracture can be profound: this fracture may progress into an unstable fracture t hat leads to signifi cant disability. Bone scans assist in the early diagnosis of this fracture. We present a case of osteoporotic p elvic insuffi ciency fracture after bilateral TKA. A 76 year-old female underwent bilateral TKA for advanced osteoarthritis in her bot h knees. She also had osteoporosis, and thus we fi lled an oral bisphosphonate (weekly Risedronate) prescription. Nine months after TKAs, she presented with signifi cant pain around the left buttock and inguinal area without specifi c trauma. With the use of plain radiog raphs and a bone scan, a pelvic insuffi ciency fracture was detected. We successfully treated the patient with conservative management including rest with a pelvic strap, and continued medication for osteoporosis.