Vitamin D deficiency adversely affects early post-operative functional outcomes after total knee arthroplasty.

PURPOSE: Vitamin D has received considerable attention in recent years owing to the increasing evidence of its importance in muscle function and physical performance. The present study attempted to determine whether patients with low serum vitamin D levels had impairment in early functional outcomes following total knee arthroplasty (TKA). METHODS: This was a prospective cohort study that included 92 patients. Patients were divided into two groups according to their vitamin D levels as assessed at the preoperative visit: (1) vitamin D-deficient group, serum 25-hydroxyvitamin D3 (25(OH)D) levels <12 ng/mL; (2) vitamin D non-deficient group, serum 25(OH)D levels ≥12 ng/mL. American Knee Society Score (KSS) and four other performance tests including the alternative step test (AST), six-metre walk test (SMT), sit-to-stand test (STS), and timed up and go test (TUGT) were used for assessment of post-operative function. All assessments were performed one day before and three months after TKA. RESULTS: Of the 92 patients included in the study, 87 patients performed all required assessments. The mean post-operative functional KSS was significantly lesser in the vitamin D-deficient group than in the vitamin D non-deficient group (67.2 vs. 73.4, p = 0.031). The mean values of time taken for post-operative AST (16.6 vs. 14.6 s, p = 0.033) and SMT (8.8 vs. 7.7 s, p = 0.012) were significantly longer in the vitamin D-deficient group than in the vitamin D non-deficient group. Post-operative STS and TUGT demonstrated higher values for mean time taken in the vitamin D-deficient group than in the vitamin D non-deficient group, but these were not statistically significant (13.6 vs. 12.4 s, not significant (n.s.); 12.7 vs. 11.7 s, n.s., respectively). CONCLUSION: Early post-operative functional outcomes following TKA appear to be adversely affected by vitamin D deficiency. LEVEL OF EVIDENCE: Prospective cohort study, Level II.

Risk factors of avascular necrosis of the femoral head and fixation failure in patients with valgus angulated femoral neck fractures over the age of 50 years.

INTRODUCTION: The aim of our study was to identify the risk factors for avascular necrosis of the femoral head (AVN) and fixation failure (FF) after screw osteosynthesis in patients with valgus angulated femoral neck fractures. PATIENTS AND METHODS: We conducted a retrospective study of 308 patients (mean age, 72.5 years, range, 50-97 years), with a mean follow-up of 21.4 months (range, 12-64 months). The risk for failure in treatment (FIT) associated with patient- and fracture-related factors was evaluated by logistic regression analyses. RESULTS: FIT was identified in 32 cases (10.3%): 22 cases (7.1%) of AVN and 10 cases (3.2%) of FF. Initial valgus tilt>15° (p=0.023), posterior tilt>15° (p=0.012), and screw sliding distance (p=0.037) were significantly associated with FIT. FIT occurred in 7 patients (5.2%) with B1.2.1 fractures and 17 patients (48.6%) with B1.1.2 fractures (p<0.001). The odds of FIT were 17-fold higher in patients with initial valgus and posterior tilts>15° (B1.1.2) compared to patients with <15° of tilt in both planes (B1.2.1). CONCLUSION: The severity of initial deformity predicts AVN and FF in patients with valgus angulated femoral neck fractures. Patients with an initial valgus and posterior tilt>15° are reasonable candidates for primary arthroplasty due to high risk of FIT.

Adiponectin provides additional information to conventional cardiovascular risk factors for assessing the risk of atherosclerosis in both genders.

BACKGROUND: This study evaluated the relation between adiponectin and atherosclerosis in both genders, and investigated whether adiponectin provides useful additional information for assessing the risk of atherosclerosis. METHODS: We measured serum adiponectin levels and other cardiovascular risk factors in 1033 subjects (454 men, 579 women) from the Korean Genomic Rural Cohort study. Carotid intima-media-thickness (CIMT) was used as measure of atherosclerosis. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated using multiple logistic regression, and receiver operating characteristic curves (ROC), the category-free net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated. RESULTS: After adjustment for conventional cardiovascular risk factors, such as age, waist circumference, smoking history, low-density and high-density lipoprotein cholesterol, triglycerides, systolic blood pressure and insulin resistance, the ORs (95%CI) of the third tertile adiponectin group were 0.42 (0.25-0.72) in men and 0.47 (0.29-0.75) in women. The area under the curve (AUC) on the ROC analysis increased significantly by 0.025 in men and 0.022 in women when adiponectin was added to the logistic model of conventional cardiovascular risk factors (AUC in men: 0.655 to 0.680, p = 0.038; AUC in women: 0.654 to 0.676, p = 0.041). The NRI was 0.32 (95%CI: 0.13-0.50, p<0.001), and the IDI was 0.03 (95%CI: 0.01-0.04, p<0.001) for men. For women, the category-free NRI was 0.18 (95%CI: 0.02-0.34, p = 0.031) and the IDI was 0.003 (95%CI: -0.002-0.008, p = 0.189). CONCLUSION: Adiponectin and atherosclerosis were significantly related in both genders, and these relationships were independent of conventional cardiovascular risk factors. Furthermore, adiponectin provided additional information to conventional cardiovascular risk factors regarding the risk of atherosclerosis.