Outcome of surgery for chronic Achilles tendinopathy - A critical review

Achilles tendinopathy is often treated surgically after failure of nonopera tive management, but results are not uniformly excellent. We critically ass essed the methods of 26 studies that reported surgical outcomes of patients with this condition. Using 10 previously published criteria, and blinded t o study outcomes, we derived a "methodology score" (0 to 100) for each stud y. This score was highly reproducible (r = 0.99, P < 0.01). Scores were gen erally low concerning the type of study, subject selection process, and out come measures, which indicates methods deficiency in the way the study was designed, performed, and analyzed. We found a negative correlation between reported success rate and overall methods scores (r = -0.53, P < 0.01), and a positive correlation between year of publication and overall methods sco re (r = 0.70, P < 0.01). Study methods may influence reported surgical outc ome, and we suggest guidelines for improving study design in this area of c linical research. We acknowledge that study methods have improved over the course of the past 20 years.