Clinical and biomechanical outcomes following patellar tendon repair with suture tape augmentation

PURPOSE

Patellar tendon ruptures (PTR) occur predominantly in middle-aged patients following indirect trauma. The aim of this study was to quantify the short-term results using a suture tape augmentation technique for the repair of PTR.

METHODS

All consecutive patients with acute (< 6 weeks) PTR who underwent suture tape augmentation between 03/2014 and 11/2019 at a single institution with a minimum follow-up of 12 months were retrospectively evaluated. Outcome measures included Visual Analog Scale (VAS) for pain, Tegner Activity Scale (TAS) and return to sport rates, Lysholm score, International Knee Documentation Committee subjective knee form (IKDC) as well as Knee Injury and Osteoarthritis Outcome Score (KOOS). Additionally, a standardized clinical examination and an isometric strength evaluation of knee extension and flexion were performed. It was hypothesized that high return to sport rates and good functional outcome would be observed and that the majority of patients would not present with a severe (> 20%) knee extension strength deficit when compared to the contralateral side.

RESULTS

A total of 7 patients (mean age 37.0 ± SD 13.5 years; 6 male/1 female) were available for final assessment at a median follow-up of 17.0 (25-75% IQR 16.0-77.0) months. Three injuries occurred during ball sports, two injuries occurred during winter sports, and one injury each occurred during a motorcycling and skateboarding accident. The average time between trauma and surgery was 4.7 ± 2.6 days. At follow-up, patients reported little pain (VAS: 0 [0-0.4]). Return to sport was possible for all patients 8.9 ± 4.0 months postoperatively at a high level (TAS: 7.0 [6.0-7.0]). Five patients (71.4%) returned to the preinjury level of play, and 2 (28.6%) did not return to the preinjury level of play. Patient-reported outcome measures were moderate to good (Lysholm score: 80.4 ± 14.5; IKDC: 84.2 ± 10.6; KOOS subscales: pain 95.6 ± 6.0, symptoms 81.1 [64.9-89.1], activities of daily living 98.5 [94.1-100], sport and recreation function 82.9 ± 14.1 and knee-related quality of life 75.9 ± 16.3). All patients were very satisfied (57.1%) or satisfied (42.9%) with the postoperative result. No postoperative complications were reported. Strength measurements revealed a severe knee extension deficit in 3 patients (42.9%), but no significant deficit of isometric knee extension or flexion strength in comparison with the contralateral side was observed overall (p > 0.05).

CONCLUSION

Suture tape augmentation in acute PTR repair leads to good functional outcome without major complications. Although a severe knee extension strength deficit may occur in some patients postoperatively, an excellent return to sports rate and high patient satisfaction can be expected nonetheless.

LEVEL OF EVIDENCE

Retrospective cohort study; III.

Midterm outcome and strength assessment after quadriceps tendon refixation with suture anchors

PURPOSE

Quadriceps tendon ruptures (QTR) occur predominantly in middle-aged patients through violent eccentric contraction that occurs either when trying to regain balance or during a fall on the hyperflexed knee. The aim of this study was to quantify midterm postoperative results, including strength potential measured via standardized strength tests following acute (< six weeks) quadriceps tendon refixation using suture anchors.

METHODS

All consecutive patients with QTR who underwent surgical suture anchor refixation between 2012 and 2019 at a single institution with a minimum follow-up of 12 months were retrospectively evaluated. Outcome measures included Tegner Activity Scale (TAS), Lysholm score, International Knee Documentation Committee subjective knee form (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS) subscales, return to work rates, and Visual Analog Scale (VAS) for pain. Additionally, a standardized clinical examination and an isometric strength assessment of knee extension and flexion were performed.

RESULTS

A total of 17 patients (median age 61.0 [25-75% IQR 50.5-72.5]) were available for final assessment at a mean follow-up of 47.1 ± SD 25.4 months. The majority of patients were male (82.4%) and most injuries occurred due to a fall on the hyperflexed knee (76.5%). The average time interval between trauma and surgery was 12.7 ± 7.5 days. Patients achieved a moderate level of activity postoperatively with a median TAS of 4 (3-5.5) and reported good to excellent outcome scores (Lysholm score: 97 (86.5-100); IKDC: 80.7 ± 13.5; KOOS subscales: pain 97.2 (93.1-100), symptoms 92.9 (82.5-100), activities of daily living 97.1 (93.4-100), sport and recreation function 80 (40-97.5) and knee-related quality of life 87.5 (62.5-100). All patients were able to fully return to work and reported little pain [VAS: 0 (0-0)]. No postoperative complications were reported. Strength measurements revealed a significant deficit of knee extension strength in comparison to the contralateral side (p = 0.011).

CONCLUSION

Suture anchor refixation of acute QTR leads to good functional results and high patient satisfaction without major complications. Isometric knee extension strength, however, may not be fully restored compared to the unaffected side.

Midterm outcome and strength assessment after proximal rectus femoris refixation in athletes

PURPOSE

Proximal rectus femoris avulsions (PRFA) are relatively rare injuries that occur predominantly among young soccer players. The aim of this study was to evaluate midterm postoperative results including strength potential via standardized strength measurements after proximal rectus femoris tendon refixation. It was hypothesized that the majority of competitive athletes return to competition (RTC) after refixation of the rectus femoris tendon without significant strength or functional deficits compared to the contralateral side.

METHODS

Patients with an acute (< 6 weeks) PRFA who underwent surgical refixation between 2012 and 2019 with a minimum follow-up of 12 months were evaluated. The outcome measures compiled were the median Tegner Activity Scale (TAS) and mean RTC time frames, Harris Hip Score (HHS), Hip and Groin Outcome Score (HAGOS) subscales, International Hip Outcome Tool-33 (iHOT-33), and Visual Analog Scale (VAS) for pain. In addition, a standardized isometric strength assessment of knee flexion, knee extension, and hip flexion was performed to evaluate the functional result of the injured limb in comparison to the uninjured side.

RESULTS

Out of 20 patients, 16 (80%) patients were available for final assessment at a mean follow-up of 44.8 ± SD 28.9 months. All patients were male with 87.5% sustaining injuries while playing soccer. The average time interval between trauma and surgery was 18.4 ± 8.5 days. RTC was possible for 14 out of 15 previously competitive athletes (93.3%) at a mean 10.5 ± 3.4 months after trauma. Patients achieved a high level of activity postoperatively with a median (interquartile range) TAS of 9 (7-9) and reported good to excellent outcome scores (HHS: 100 (96-100); HAGOS: symptoms 94.6 (89.3-100), pain 97.5 (92.5-100), function in daily living 100 (95-100), function in sport and recreation 98.4 (87.5-100), participation in physical activities 100 (87.5-100), quality of life 83.1 ± 15.6; iHot-33: 95.1 (81.6-99.8)). No postoperative complications were reported. Range of motion, isometric knee flexion and extension, as well as hip flexion strength levels were not statistically different between the affected and contralateral legs. The majority of patients were "very satisfied" (56.3%) or "satisfied" (37.5%) with the postoperative result and reported little pain (VAS 0 (0-0.5)).

CONCLUSION

Surgical treatment of acute PRFA yields excellent postoperative results in a young and highly active cohort. Hip flexion and knee extension strength was restored fully without major surgical complications.

LEVEL OF EVIDENCE

Retrospective cohort study; III.