Vitamin D is an important vitamin for the human body, responsible for many important cellular functions. It has also been shown to be associated with bone density and overall well being. The most important compounds of Vitamin D for humans are known as Vitamin D2 and Vitamin D3. Vitamin D2 can be found in plants, and are more commonly found as nutritional supplements. Vitamin D3 is found in animal products and, more prominently, produced by the skin when exposed to UV-B radiation from the sun. Deficiency in Vitamin D, whether through diet or lack of sun exposure, can cause a variety of symptoms, including some more serious conditions such as Osteomalacia (Rickets in children), or softening of the bones.
In a recent study published in Annals of Nutrition and Metabolism, researchers conducted a meta-analysis on the effect of Vitamin D in patient outcomes after hip or knee joint surgery. Data from 2593 patients with osteoarthritis, mean age 70 years, was analyzed from 12 different studies. Patients were assessed on their Harris Hip Score (HHS), a clinician-based outcome measure ranging from 0 – 100 with higher scores representing less dysfunction and better outcomes. Preoperatively, patients with Vitamin D deficiency had lower HHS compared to their non-deficient counterparts. Postoperatively, Vitamin D deficient patients had significantly lower scores in comparison. Additionally, hospital stays were 1-2 days longer for deficient patients.
The researchers concluded that Vitamin D status could affect surgical outcomes and recovery, noting a high prevalence of Vitamin D deficiency (approximately 47%) in patients with osteoarthritis. However, they also determined that more research was necessary in order to confirm these findings.