Outcomes following osteosynthesis of periprosthetic hip fractures around cemented tapered polished stems.

We retrospectively reviewed outcomes of 79 patients with periprosthetic hip fractures around cemented tapered polished stem (CTPS) implants treated with osteosynthesis between January 1997 and July 2011. All patients underwent open reduction and fixation using a broad dynamic compression plate (DCP). Seventy two (91%) of fractures united. There were seven (9%) non-unions with failure of metal work, three (4%) as a result of infection and four (5%) due to mechanical failure. Significant subsidence (>5mm) of the implant was seen in seven (9%) of cases. Ten (13%) cases developed post-operative infection. Non-anatomic reduction and infection were identified as predictors of poor outcome. This is the largest series of a very specific group of periprosthetic fractures treated with osteosynthesis. Open reduction internal fixation with a broad dynamic compression plate for patients with periprosthetic hip fractures around the tip of cemented tapered polished stems is a suitable treatment provided there is no bone loss and the fracture can be precisely, anatomically, reduced and adequately fixed.

Natural acetabular orientation in arthritic hips.

OBJECTIVES: Acetabular component orientation in total hip arthroplasty (THA) influences results. Intra-operatively, the natural arthritic acetabulum is often used as a reference to position the acetabular component. Detailed information regarding its orientation is therefore essential. The aim of this study was to identify the acetabular inclination and anteversion in arthritic hips. METHODS: Acetabular inclination and anteversion in 65 symptomatic arthritic hips requiring THA were measured using a computer navigation system. All patients were Caucasian with primary osteoarthritis (29 men, 36 women). The mean age was 68 years (SD 8). Mean inclination was 50.5° (SD 7.8) in men and 52.1° (SD 6.7) in women. Mean anteversion was 8.3° (SD 8.7) in men and 14.4° (SD 11.6) in women. RESULTS: The difference between men and women in terms of anteversion was significant (p = 0.022). In 75% of hips, the natural orientation was outside the safe zone described by Lewinnek et al (anteversion 15° ± 10°; inclination 40° ± 10°). CONCLUSION: When using the natural acetabular orientation to guide component placement, it is important to be aware of the differences between men and women, and that in up to 75% of hips natural orientation may be out of what many consider to be a safe zone. Cite this article: Bone Joint Res 2015;4:6-10.