Participation in this study will be approximately 8 weeks. 20 participants will be randomized to the treatment group and 20 to the placebo group. The treatment group will receive Vitamin D2 therapy at 50,000 IU for 8 weeks (once per week) while the placebo group will receive a placebo pill (once per week) that is identical in nature. Participants have 2 study visits respectively at Week 0 and Week 8, and 1 phone follow-up visit at Week 1. In addition to the administration of Vitamin D2 or placebo mentioned above, other study procedures include informed consent, physical exam, questionnaires (brief pain assessment, and SF-12 to assess limitations on physical activity), review of medical records, medication and supplement review, blood draw, and phone followup. Subjects will be asked to stop any supplemental Vitamin D therapy to maintain an equal dose within patients in the Vitamin D2 and placebo group.