Methods/intervention

A total of 449 adult patients (mean age, 36.2– 57.4 years) were evaluated in the included studies, with sample sizes ranging from 20 to 158 and plantar fasciitis symptom duration varying from eight weeks to 2.9 years. The concentration of the dextrose solution ranged from 1.5% to 20% - Male and female patients aged ≥18 years with chronic plantar fasciitis were included. -

The primary outcome of this systematic review was pain using a visual analogue scale (VAS) or a numerical rating scale (NRS) and the secondary outcome was foot function using any available scale, including foot function index (FFI), the American Orthopedic Foot and Ankle Score (AOFAS), and foot and ankle ability measure (FAAM).

The follow-up time after the final session of treatment was categorized into immediate (≤1 month), short-term (1–3 months), intermediate-term (3–6 months), and long-term (> 6 months). - Studies with more than two arms in which at least one arm received prolotherapy and another received a non- surgical treatment for plantar fasciitis were included. - Eight studies were included in the meta-analysis. - Only one (1/8) had unclear risk of bias, while the rest (7/8) had high risk of bias based on Cochrane’s Collaboration tool. - The frequency of DPT ranged from one to three injections, 1–3 weeks apart. Quality (risk of bias) assessment

The Cochrane Collaboration’s tool for assessing risk of bias was used for quality assessment. The following parameters were evaluated: random sequence generation, allocation concealment, performance bias, detection bias, attrition bias, and reporting bias. How did people go with pain in the short, intermediate, and long term? All the included trials reported the short-term effects of interventions on pain while only six reported immediate-term and three long-term effects on pain. Short term: - There were significant large short-term effects of DPT compared to placebo/other non-surgical interventions on plantar fascia pain. - Mansiz-Kaplan et al. reported a significant short-term pain reduction with DPT compared to placebo. - Umay Atlas et al. showed that DPT was significantly more effective than placebo (saline) for pain reduction in the short-term - Esrsen et al. illustrated similar results with DPT compared to exercise. On the other hand, DPT was not superior to the control groups in this regard in other studies. Intermediate term: - Of the six studies reporting immediate term effects on pain, Ersen et al.and Mansiz-Kaplan et al. showed significant immediate-term pain reduction with DPT compared to exercise and placebo.

Overall, DPT was not superior to placebo/other non-surgical interventions for immediate-term pain reduction in plantar fasciitis. Long term: Of the three trials evaluating long-term effects on pain, only Ersen et al. reported significantly better long-term pain reduction with DPT than exercise. Also, the overall effect of DPT compared to the control groups was non- significant. Foot function: Immediate-term effects on foot function were seen in short-term in all six, and long-term effects in three. There was highly severe heterogeneity in short-term foot function among the included studies. Of the three trials evaluating long-term effects on foot function, none reported significantly better long-term foot function improvement with DPT than placebo or other. Limitations: Due to the relatively few numbers of the included studies, there were insufficient trials in most of the subgroups to achieve conclusive results. Not a great deal of people Different follow up times. Performance bias – where people are disappointed, they didn’t get the treatment. Conclusions Dextrose prolotherapy appears to be useful in the short term. However, for longer time periods more studies are needed to make a definitive conclusion. Dextrose prolotherapy was only significantly superior to exercise and placebo for short- term pain reduction, while it was not better than PRP, corticosteroids, or ESWT in this respect. As performance bias was the most potential source of heterogeneity in this study, future clinical trials should consider blinding the patients where possible.