Small needle-knife versus extracorporeal shock wave therapy for the treatment of plantar fasciitis: A systematic review and meta-analysis

Background: Plantar fasciitis (PF) is the most common cause of chronic heel pain among adults. Extracorporeal shock wave therapy (ESWT) is the recommended in the current guidelines, and the small needle-knife yields acceptable clinical effects for musculoskeletal pain. Objective: To systematically compare the efficacy of the small needle-knife versus ESWT for the treatment of PF. Methods: The present review was registered in the International Prospective Register of Systematic Reviews (i.e., “PROSPERO”, CRD42023448813). Two of the authors searched electronic databases for randomized controlled trials (RCTs) comparing the small needle-knife versus ESWT for the treatment of PF, and collected outcomes including curative effect, pain intensity, and function. Risk of bias was assessed using the Cochrane Handbook Risk of Bias tool and the quality of the RCTs was evaluated according to the Jadad Scale. The same authors independently performed data extraction from the included studies, which were imported into Review Manager version 5.4.1(Copenhagen: Nordic Cochrane Centre, The Cochrane Collaboration, 2020) for meta-analysis. Results: The initial literature search retrieved 886 studies, of which 6 were eventually included in this study. Meta-analysis revealed no significant difference in curative effect (OR = 1.87; 95 % CI [0.80, 4.37], p = .15) nor short-term pain improvement (MD = 2.20; 95 % CI [-2.77, 7.16], p = .39) between the small needle-knife and ESWT. However, the small needle-knife may be more effective than ESWT for pain improvement in mid-term (MD = 9.11; 95 % CI [5.08, 13.15], p＜ .00001) and long-term follow-ups (MD = 10.71; 95 % CI [2.18, 19.25], p＜ .00001). Subgroup analysis revealed that the small needle-knife combined with a corticosteroid injection yielded a statistically significant difference in reduction of pain intensity at all follow-ups (MD = 4.84; 95 % CI [1.33, 8.36], p = .007; MD = 10.99; 95 % CI [8.30, 13.69], p＜ .00001; MD = 17.87; 95 % CI [15.26, 20.48], p＜ .00001). Meta-analysis revealed no statistical differences in short-term (MD = 1.34; 95 % CI [-3.19, 5.86], p = .56) and mid-term (MD = 2.75; 95 % CI [-1.21, 6.72], p = . 17) functional improvement between the needle-knife and ESWT groups. In a subgroup analysis of moderate-quality studies, the small needle-knife demonstrated a favorable effect on mid-term functional improvement (MD = 1.58; 95 % CI [0.52, 2.65], p = .004), with low heterogeneity (χ2 = 0.77, p = .038, I2 = 0 %). Conclusion: Pain reduction and functional improvement are essential for the treatment of PF. Therefore, treatment using the small needle-knife may be superior to ESWT. Results of this systematic review and meta-analysis may provide alternative treatment options for patients with PF as well as more reliable, evidence-based recommendations supporting use of the small needle-knife.