Prognostic Factors for Recovery from Patellar Tendinopathy in Jumping Athletes: An International Prospective Cohort...

There is no robust prognostic guides for patellar tendinopathy (PT), hence we do not understand who gets better, when and why. Therefore, we aimed to identify which combination of self-reported factors best predicts PT recovery. A previously validated, reliable online questionnaire battery yielded data from an international sample of professional and recreational jumping athletes with a one-year follow-up. Recovery was defined using Global Rating of Change, alongside full availability for training and competition. Data on > 100 plausible bio-psycho-social, demographic and sporting outcome predictors were collected; and a multivariable cox proportional-hazards model constructed.

128 athletes with PT (30.9 ± 8.9 years; 77 males (60%); Victorian Institute of Sport Assessment Questionnaire-Patellar Tendon = 61.5 ± 16.2) provided 25,284 days at risk for analysis. Recovery rate was 45%, peaking at 6-month. The multivariable model partially predicted PT recovery with acceptable performance (optimism-corrected C-statistic:0.77, 95%CI:0.74-0.79) and internal validation. Recovery was associated with lower severity (Hazard Ratio (HR) = 1.03, 95%CI 1.02-1.05), a shorter time off sport (HR = 0.93, 95%CI 0.87-0.99), feeling more rested after sleep (HR = 1.93, 95%CI 1.13-3.28), not having multiple concurrent tendon problems (HR = 0.23, 95%CI 0.07-0.69), higher training duration (HR = 1.05, 95%CI 1.01-1.10) and symptoms being modifiable by movement (HR = 2.71, 95%CI 1.21-6.09).

To the best of our knowledge, this is the first study investigating outcome predictors for PT recovery in a large international cohort of jumping athletes. The exploratory recovery model showed that a combination of self-reported sports-specific and biomedical variables were predictive of PT recovery. These findings can be used to support clinical judgements of prognosis.