Introduction. Vitamin D deficiency is common in patients undergoing total hip (THA) or total knee arthroplasty (TKA) which may affect prosthesis survival and 90-day readmission rates. The purpose of this study was to assess whether preoperative Vitamin D deficiency or insufficiency have an influence on revision, readmission, and complication rates following THA and TKA. We hypothesized that low Vitamin D levels in patients undergoing THA and TKA have a negative effect on revision rates. Methods. Patients who underwent primary THA or TKA in a 2-year period university hospital were identified and stratified into 3 groups based on preoperative 25-hydroxyvitamin D serum levels: normal levels of 30 ng/ml or greater, (2) deficient levels of 20–29.9 ng/ml, and (3) insufficient levels of less than 20 ng/ml. Patient demographics and postoperative course were collected from the electronic medical record. Results. This study found that 45% out of 197 THA had Vitamin D levels less than 30ng/ml and significantly higher odds (14.1, p=0.018) of requiring revision surgery at a mean follow-up of 34 ± 11.2 months. Out of 167 TKA, 46% were Vitamin deficient/insufficient without an influence on revision rate. Vitamin D levels did not influence 90-day readmissions, wound complications, or reaching discharge goals. Low Vitamin D levels correlated with high BMI and young patient age for THA. Conclusion. Based on the findings of this study, the authors recommend preoperative Vitamin D3 supplementation (2,000–4,000 IU daily) for patients with a BMI greater than 30kg/m. 2. undergoing THA. Patient with Vitamin D deficiency may require referral for endocrinologic work-up. Based on the findings of this study, the authors have adopted postoperative Vitamin D3 supplementation with 2,000–4,000 IU daily for 3 months as part of the rehabilitation protocol for all patients undergoing THA

The physiological effects of 1,25 vitamin D3 (1,25D) are well known and the previously held dogma was that this was the only active vitamin D metabolite. A number of methods have been employed to demonstrate the effects of 24,25-dihydroxyvitamin D3 (24,25D) on osteoblast maturation responses, in the presence of FHBP, ((3S) 1-Fluoro-3-hydroxy-4-(oleoyloxy)butyl-1-phosphonate), an agonist of lysophosphatidic acid (LPA). These include alkaline phosphatase (ALP) expression and investigation of the role of CYP27B1, which is the enzyme responsible for converting 24,25D to 1,24,25D. Ketoconazole, which inhibits the actions of CYP27B1, as well as an enzyme-linked immunosorbant assay (ELISA) for CYP27B1 were used. The results clearly demonstrate that 24,25D stimulates maturation of MG63 cells when combined with FHBP. It has also been shown that the metabolite is not converted to another active form (for example, 1,24,25D) within osteoblasts, due to the absence of CYP27B1. 24,25D is an active vitamin D metabolite and exerts its effects in a bone fide manner, rather than following conversion to another active metabolite in osteoblasts. Given it is non-calcaemic, this metabolite has the exciting potential of being used in a bone regenerative setting in orthopaedic applications

Successful osseointegration requires the production of a mechanically competent collagenous matrix, by osteoblasts, at the implant site. Lysophosphatidic acid (LPA) is a bioactive lipid which we discovered interacts with vitamin D3 (D3) to secure human osteoblast (hOB) maturation on both titanium (Ti) and hydroxyapatite. We therefore covalently attached LPA and a related compound, (3S) 1-fluoro-3-hydroxy-4-butyl-1-phosphate (FHBP), to both solid and porous Ti discs and seeded them with hOBs to assess their ability to support D3-induced cell maturation. Solid functionalised discs were washed and reused a further two times, whilst other discs were stored for 6 months. Increased alkaline phosphatase (ALP) activity indicated that both LPA and FHBP-modified Ti serve as superior substrates for securing D3-induced hOB maturation compared to unmodified metal (p < 0.001). Although total ALP activity was less for cells on recycled discs and after storage, enzyme levels were still significantly greater compared to hOBs grown on control Ti. LPA and D3 co-treatment also resulted in an increase in osteocalcin (∼17ng/ml versus 6ng/ml for D3 alone, P < 0.001) and collagen synthesis (∼310pg/ml versus <10pg/ml for D3 alone, P < 0.001). Research is ongoing to evaluate the efficacy of our modified Ti surfaces to secure hOB formation from their stem cell progenitors

Introduction. Assessment for and treatment of osteoporosis is recommended following hip fracture. All forms of osteoporosis treatment require an adequate calcium intake and normal vitamin D levels. This study assesses vitamin D levels in patients with hip fractures and describes guidelines on how to manage low vitamin D levels with high dose oral vitamin D3 (cholecalciferol). Materials and methods. Circulating 25-hydroxyvitamin D levels were measured in consecutive patients with a hip fracture over an 18 month period. Substitution therapy with high dose oral cholecalciferol was started in 2 selected cohorts; one group received substitution therapy for 3 days, the second group for 7 days. Results. 381 patients with 387 hip fractures were included. Only 27 patients had sufficient (>75 nmol/L) vitamin D levels (mean 91.2 nmol/L) and of these 22 were taking supplements. The remainder, 354 patients, had low vitamin D levels (mean 26.4 nmol/L). Substitution with 50,000 IU cholecalciferol daily for 3 days in 14 patients resulted in an increase in vitamin D levels from 29.6 nmol/L to 81.4 nmol/L (p < 0.0001), at a mean of 14 days. 71% of patients achieved levels above the desired threshold of 75 nmol/L. Substitution with 50,000 IU cholecalciferol for 7 days in 54 patients resulted in an increase in vitamin D levels from 31.4 nmol/L to 131.1 nmol/L (p < 0.0001), at a mean of 16 days. 100% of patients achieved levels above the desired threshold. No clinical or biochemical side effects were reported. Discussion. Virtually all patients who are not taking vitamin D supplements and sustain a hip fracture have abnormally low circulating vitamin D levels and all require substitution. The routine measurement of vitamin D levelsmay be unnecessary. Substitution with 50,000 IU oral cholecalciferol daily for 7 days increases vitamin D levels rapidly, safely and consistently

Aims

Orthopaedic infection is a potentially serious complication of elective and emergency trauma and orthopaedic procedures, with a high associated burden of morbidity and cost. Optimization of vitamin D levels has been postulated to be beneficial in the prevention of orthopaedic infection. This study explores the role of vitamin D in orthopaedic infection through a systematic review of available evidence.