Effectiveness of platelet-rich plasma therapy in wound healing of pilonidal sinus surgery: A comprehensive systematic review and meta-analysis.

Pilonidal disease (PD) is a chronic situation which may cause pain, discomfort, inflammation, discharges, and inability to do daily routines. Among two main methods of surgery, open healing is preferred by surgeons since it associates with lower risk of recurrence; however, it could complicate the wound condition by delaying the healing process. For this meta-analysis, a search in Medline, Embase, and Scopus was performed in June 2017 with no restrictions placed on the publication date or languages. Then, time to healing was considered as the effect size and all the data from trials were extracted. The heterogeneity and the variation in pooled estimation were assessed using Cochran's Q test and I-squared, respectively. Meta-regression was used to examine the relationship between the effect size and year, studies' sample sizes, proportion of male gender and age with the cause of heterogeneity. From 11 selected articles finally 4 met our inclusion and exclusion criteria with the total number of 484 patients. Using a fixed-effect model, pool effect was detected 0.642 (95% CI: 0.485-0.798). A homogeneity of pooled effect size estimate for the studies was also found (Cochran Q test, p-value = 0.844, I-square = 0.0%). Moreover, results of meta-regression showed no statistically significant association between the effect size and patients' mean age, year of publication, total sample size, and sex proportion (0.51 < p-values < 0.98). Platelet-rich plasma therapy for PD wounds appeared more effective than classic wound dressing.