Bisphosphonate-related atypical femoral fracture with bone metastasis of breast cancer: case report and review.

BACKGROUND: Intravenous bisphosphonates (BPs) have been used to reduce the frequency of skeletal-related events due to bone metastases of several kinds of cancers. Although many studies on BP-related atypical fractures (BRAFs) due to the use of BP for osteoporosis treatment have been reported, few reports on BRAFs arising as a complication of long-term BP use for bone metastasis of cancer are available. CASE REPORT: A 62-year-old woman with a history of breast cancer presented with right thigh pain after she had a fall. Radiographs indicated a transverse fracture in the shaft of the right femur. She had been on zoledronate treatment for six years. Based on radiographic and histopathological findings, we concluded that the fracture was not a pathological fracture associated with metastasis but was a complication of long-term BP treatment. CONCLUSION: Clinical oncologists should consider the possibility of BRAFs in patients on long-term zoledronate treatment for bone metastases.

Accuracy of cup height and medialization in THA for dysplastic hip osteoarthritis using an imageless navigation system.

In total hip arthroplasty (THA) for dysplastic hip osteoarthritis, bony deformity makes it difficult to identify the correct cup height and medialization. The authors developed a new technique for registration and navigation of cup position for dysplastic hips using an imageless navigation system. Eighty dysplastic hips (Crowe type I, n=58; type II, n=18; type III, n=4) underwent THA. Thirty-four hips were operated on while in the supine position and 46 hips were operated on while in the lateral position. Before capsulectomy, the anterior pelvic plane and the position of the femur were registered. After exposure of the acetabulum, the teardrop, posterior rim, and medial wall of the acetabulum were registered. Then the cup height, cup medialization, cup inclination, anteversion, and leg lengthening were navigated. The difference between the navigated and radiographic cup heights was 4.5 ± 4.0 mm, the difference in cup medialization was 3.0 ± 2.5 mm, the difference in cup inclination was 4.3° ± 3.1°, the difference in cup anteversion was 5.5° ± 3.8°, and the difference in leg lengthening was 3.7 ± 3.0 mm. Comparison of the first 20 cases with the last 20 cases showed that the accuracy of cup medialization was significantly improved. These differences were not affected by Crowe type or surgical position. Because the correct cup height and medialization are key issues in THA for dysplastic hip osteoarthritis, the accuracy of cup height and medialization in this imageless navigation system were acceptable for clinical application.