Periprosthetic stress fracture around a well-fixed type 2B short uncemented stem

Abstract

Despite the theoretical advantages of uncemented short stems, postoperative thigh pain is still matter of concern and can be attributed to different causes. We report a peculiar case of a stress fracture around a short cementless stem with cervico-metaphyseal fixation in an otherwise healthy patient. We implanted a MiniHipTM stem in a 43 year-old male professional golf player for the treatment of primary osteoarthritis using a ceramic on ceramic bearing. Against medical advice, the patient started to play soccer at the 4th postoperative month and was completely asymptomatic to that extent; but at 8 months follow-up and without a history of trauma he started complaining about progressive hip pain. After ruling out infection and loosening, histological analysis from a bone biopsy confirmed the diagnosis of stress fracture. Although revision surgery was initially scheduled, pain started to decrease gradually with protected weight-bearing (crutches) and disappeared around the first postoperative year, remaining the patient asymptomatic at 2 and half years of follow-up, with radiographs depicting a healed fracture with a hypertrophic callus. We encourage surgeons to be aware of the existence of periprosthetic stress fractures as a source of thigh pain (sometimes intractable), and despite being infrequent, they should always be contemplated, providing that these cases can be managed conservatively with rest and limited weight-bearing. After this uncommon case, we suggest to align the stem in order to equally distribute loads onto the medial calcar and the lateral femoral cortical.