The significance of the vitamin D metabolism in the development of periprosthetic infections after THA and TKA: a prospective matched-pair analysis of 240 patients

BACKGROUND: The importance of the vitamin D homeostasis in infections is already known. However, its significance in periprosthetic infections (PPIs) after total hip arthroplasty and total knee arthroplasty is largely unexplored. The aim of the study is to precisely analyze the vitamin D balance in patients with PPIs after total hip arthroplasty and total knee arthroplasty. Here, cases with primary endoprosthesis implants and aseptic loosening are used as comparison groups. MATERIALS AND METHODS: In this prospective matched-pair analysis, patients with PPI at the hip and knee joints were included in the study group (SG). The control groups (CGs) consisted of patients with primary implants (CG I) and who underwent replacement surgery due to aseptic loosening (CG II). In addition to 25 OH vitamin D3 and calcium, bone mineral and protein parameters were determined. An osteoporosis-specific questionnaire was collected. RESULTS: There are no significant differences in the 25 OH-vitamin D levels between the SG (17.9±8.9) and both CGs (CG I: 16.8±6.90; CG II: 19.7±7.90). However, compared with the SG, significantly higher levels of calcium (Ca) and bone-specific alkaline phosphatase were found in both CGs in comparison with the SG. Significantly lower values concerning the protein balance in PPI were conspicuous. Acute PPI showed a significant reduction in 25 OH vitamin D3 compared with chronic infections (8.3±5.98 vs 21.6±8.40, P=0.002). Calcium and protein balance were also significantly reduced in acute PPIs. CONCLUSION: Acute PPIs of the hip and knee joints show a significantly reduced calcium and 25 OH vitamin D3 levels as well as lowered proteins (albumin and total protein) compared with chronic infections as well as primary endoprostheses and aseptic replacement operations. Substitution of vitamin D3 and calcium with simultaneous adaptation of the protein balance is recommended in all PPIs, especially in the acute PPI.