Defining vitamin D deficiency or insufficiency by a single cutoff value
remains controversial because of the variability of its functional effects
on each individual.

A variety of orthopaedic populations have been shown to have
insufficient vitamin D levels, including patients with trauma, National
Football League (NFL) athletes, and patients undergoing elective
shoulder arthroplasty and foot and ankle procedures, which may be
a reflection of the overall prevalence of hypovitaminosis D.

Although supplementation may not prevent osteoporotic fractures,
supplementation has been shown to effectively improve vitamin D
levels in deficient patients.

Sufficient vitamin D levels may be associated with improved
functional and clinical outcomes in patients undergoing elective
orthopaedic surgical procedures.