Unable to recruit enough subjects to attain the minimum sample size.

The purpose of this multisite randomized controlled trial (RCT) is to compare the short-term (6 week) and long-term (6 month) effect of chiropractic care combined with a specific nutritional supplement regimen to chiropractic care with a placebo supplement for patients with ankle sprains, in terms of improvement in physical function and pain.

Specific Aim 1: to compare the short-term (6 week) effect of chiropractic care combined with a specific nutritional supplement regimen to chiropractic care with a placebo nutritional supplement for patients with ankle sprains, in terms of speed and amount of improvement in physical function and pain. Our hypothesis is that chiropractic care plus nutritional supplements designed to supply necessary nutrients for ligament healing will have improved outcomes in pain and disability, compared to chiropractic care plus placebo. We will use the Foot and Ankle Ability Measure Activities of Daily Living Subscale (FAAM ADLS) to measure outcomes.

Specific aim 2: to compare the long-term (6 month) effect of chiropractic care combined with a specific nutritional supplement regimen to chiropractic care with a placebo nutritional supplement for patients with ankle sprains, in terms of speed and amount of improvement in physical function and pain. Our hypothesis is that chiropractic care plus nutritional supplements designed to supply necessary nutrients for ligament healing will have improved outcomes as measured by the FAAM ADLS, compared to chiropractic care plus placebo.

Specific aim 3: to explore any changes in the attitude, knowledge and behavior of chiropractic interns and practitioners of the role of nutrition in treating musculoskeletal injuries, pre- and post-intervention. We will also compare their responses to those of a population of students and practitioners who did not participate in the project, as a comparison group.

Inclusion Criteria:

• Acute ankle sprain, defined as ankle sprain within the past 7 days, by patient report. Treating clinician will verify diagnosis via clinical examination.
• Ages 18-50; ankle sprains are more common in this age group.

Exclusion Criteria:

• Diagnosis of grade III ankle sprain, fracture or dislocation; fracture will be diagnosed using the Ottawa ankle rules11,12
• Contraindications to chiropractic care, such as fracture or other abnormalities found by history, examination, or x-rays, as determined by the treating or supervising clinician.
• Pregnancy: although it is unlikely that the nutritional supplements would have adverse effects on the fetus, we are excluding pregnant women as a safeguard.
• Unwilling or unable to regularly take the supplements (e.g., vegetarians; known sensitivity by self-report; patients will be shown the ingredient list prior to signing the informed consent).
• Litigation for a health-related claim (in process or pending).
• History of ankle surgery or presence of ankle hardware (pins, screws, etc.), by patient report.
• History of diabetic or other peripheral neuropathy, by patient report.
• Current use of prescription or nonprescription medications that may interact with experimental or placebo supplements, by patient report.