Clinical Outcomes Following Repair of Acute Patellar Tendon Injuries at a Tertiary Trauma Centre: A 16-Year Retrospective Series

Background Patellar tendon rupture is an uncommon but functionally debilitating injury requiring prompt surgical repair to restore the knee extensor mechanism. Evidence regarding the effect of short in-hospital delays to surgery on postoperative outcomes remains limited. This study evaluated short-term clinical outcomes following acute patellar tendon repair at a tertiary trauma centre over a 16-year period. Methods A retrospective case series was conducted using a prospectively maintained trauma registry from a tertiary hospital in the East Midlands, United Kingdom (2008-2024). Clinical records, operative notes, and follow-up documentation were reviewed. Data collected included patient demographics, injury characteristics, imaging modality, repair technique, surgeon grade, time to surgery (TTS), postoperative range of motion (ROM), follow-up duration, and complications. The primary outcome was postoperative knee flexion ROM at discharge. Statistical analysis included Pearson correlation and Spearman's correlation for non-parametric analysis, independent-samples t-tests, and one-way ANOVA. Results Thirty-four patients underwent operative repair of acute patellar tendon rupture. The cohort had a male-to-female ratio of 7.5:1, with a mean age of 50.7 years. Mean TTS was 2.5 days, and mean postoperative ROM at discharge was 105.4°. All patients with documented range-of-motion data achieved at least 85° of knee flexion, recorded at the final outpatient review. Complications occurred in nine (26.5%) patients, although most were minor and managed non-operatively. There was no significant association between TTS and postoperative ROM at discharge (r = -0.11, p = 0.59), suggesting that short in-hospital delays within the observed acute treatment window were not statistically associated with ROM at discharge. No statistically significant differences in short-term outcomes were observed between consultant-led and supervised registrar-led procedures, although this comparison was exploratory and unadjusted. Additional preoperative imaging was not associated with a statistically significant increase in TTS. Conclusion Primary repair of acute patellar tendon rupture produced satisfactory short-term functional outcomes with a low rate of major complications. Within the observed acute treatment window (0-9 days), no association was identified between time to surgery and knee flexion ROM at discharge, although the study was underpowered to exclude small-to-moderate effects. Supervised trainee-led surgery was associated with short-term outcomes similar to those of consultant-led procedures, although case allocation was not randomised. These findings are exploratory and confined to short-term outcomes. Larger prospective studies incorporating validated patient-reported outcome measures are required to better define prognostic factors following acute patellar tendon repair.