Studies of surgical outcome after patellar tendinopathy: clinical significance of methodological deficiencies and guidelines for future studies

Patellar tendinopathy is often treated surgically after failure of conserva tive treatment but clinical experience suggests that results are not unifor mly excellent, The aim of this review was to (i) identify the different sur gical techniques that have been reported and compare their success rates, a nd (ii) critically assess the methodology of studies that have reported sur gical outcomes, Twenty-three papers and two abstracts were included in the review Surgical procedures were categorized and outcomes summarized. Using ten criteria, an overall methodology score was derived for each paper. Crit eria for which scores were generally low (indicating methodological deficie ncy) concerned the type of study subject selection process and outcome meas ures. We found a negative correlation between papers' reported success rate s and overall methodology scores (r=-0.57, P<0.01). There was a positive co rrelation between year of publication and overall methodology score (r=0.68 , P<0.001). We conclude that study methodology may influence reported surgi cal outcome. We suggest practical guidelines for improving study design in this area of clinical research, as improved study design would provide clin icians with a more rigorous evidence-base for treating patients who have re calcitrant patellar tendinopathy.