Effects of preoperative serum vitamin D levels on early clinical function outcomes and the moderate-to-severe pain prevalence in postmenopausal women after primary total knee arthroplasty

To investigate the impact of vitamin D levels on early clinical function outcomes and the potential risk factors of moderate-to-severe pain prevalence in postmenopausal women after primary total knee arthroplasty (TKA).From April 2017 to December 2019, 226 women were retrospectively recruited. The women were divided into two groups based on their preoperative serum 25-hydroxyvitamin D levels: (1) vitamin D-sufficient group (≥30 ng/mL); (2) vitamin D-deficient group (<30 ng/mL). The visual analog scale, Western Ontario and McMaster Arthritis Index score, and Knee Society Score were used to evaluate clinical outcomes. Risk factors for developing postoperative moderate-to-severe knee pain were studied using multivariate binary logistic regression analyses.There was no significant difference in preoperative clinical function assessment between the two groups. The difference in postoperative Western Ontario and McMaster Arthritis Index score between the two groups was statistically significant (15.3 ± 0.7 vs 15.6 ± 0.7: P = 0.02). However, the differences in postoperative visual analog scale and Knee Society Score scores between the two groups were not significant (P > 0.05). The incidence of postoperative moderate-to-severe pain was 16.4% (95% CI 11.8%-21.9%). Multivariate logistic regression analysis revealed that vitamin D deficiency, smoking, and high body mass index were potential risk factors for moderate-to-severe knee pain in postmenopausal women early after TKA (P < 0.05).Preoperative vitamin D deficiency may adversely affect early functional outcomes in postmenopausal women after TKA. In addition, vitamin D deficiency, smoking, and high body mass index were independent risk factors for moderate-to-severe knee pain after surgery.