The utility of post-operative hip radiographs in patients treated with hip hemiarthroplasty for femoral neck fractures.

BACKGROUND: Patients treated with hip hemiarthroplasty for low energy femoral neck fractures routinely undergo hip radiographs at each postoperative clinic visit regardless of history and physical findings. No studies to date have evaluated the effectiveness of this accepted practice. The goal of this study was to identify the postoperative utility of both history and physical (H/P) and hip radiographs in the treatment course of patients treated with hip hemiarthroplasty for low energy femoral neck fractures. METHODS: A retrospective chart review was performed on consecutive patients treated with hip hemiarthroplasty for low energy femoral neck fractures. An abnormal H/P and hip radiographs as well as a change in treatment course were recorded at each clinic or emergency department visit. RESULTS: Five hundred and eighty-three patients met inclusion criteria, consisting of 1177 clinic and 50 emergency department (ED) visits. An abnormal radiograph in the presence of a normal H/P did not lead to a change in treatment course. An abnormal H/P alone changed treatment course in 28 (3%) clinic visits and 18 (36%) ED visits. An abnormal H/P and the presence of an abnormal hip radiograph changed the treatment course in 23 (2%) clinic visits and 18 (36%) ED visits. In only one case - 0.3% of abnormal radiographs or 0.08% of 1177 clinic visits - did an abnormal hip radiograph change treatment course in the setting of an abnormal H/P within 6 months from surgery. The average cost of a series of hip and pelvis radiographs was $242. CONCLUSIONS: Abnormal radiographs do not change treatment course in the presence of a normal H/P. Hip radiographs obtained in clinic within 6 months of surgery rarely lead to a change in treatment course and thereby are a source of excess cost and radiation exposure to the patient.

alpha-Smooth muscle actin-expressing cells and lubricin in periprosthetic tissue.

The objective of the study was to evaluate the distributions of (1) cells expressing the contractile actin isoform, alpha-smooth muscle actin (alpha-SMA) and (2) a lubricating and antiadhesion glycoprotein, lubricin, in the tissue around loose joint replacement prostheses in human subjects. Periprostehtic tissue resected at revision arthroplasty of noncemented glenoid components of total shoulder arthroplasties was obtained from 10 patients. Samples of periprosthetic tissue were stained with monoclonal antibodies to alpha-SMA and lubricin. alpha-SMA was found in cells, principally of fibroblast morphology, in many of the fields of view (FOVs) in samples from all patients. Moderate correlations were observed between the percentage of FOVs containing alpha-SMA-expressing cells and the percentages of FOVs containing polyethylene (R(2) = 0.79) and metallic (R(2) = 0.75) particles. Lubricin was identified (1) as a discrete layer on the surface, (2) within the extracellular matrix, and (3) intracellularly. These lubricin-positive features were found in samples from all patients. Strong correlations were noted between the percentages of FOVs with matrix and intracellular lubricin staining (R(2) = 0.97) and between the percentages of FOVs with surface and matrix staining for lubricin (R(2) = 0.96). Having established the presence of alpha-SMA and lubricin in periprosthetic tissue, hypotheses regarding their role in the development and persistence of periprosthetic tissue can be synthesized for future study: for example, alpha-SMA-enabled contracture of the fibrous periprosthetic tissue results in its densification, and lubricin-coated surfaces interfere with integrative repair processes necessary for resorption and remodeling.