Biomechanical Comparison of Ulnar Collateral Ligament Reconstruction With and Without Suture Augmentation

Abstract

Background:

A common concern associated with elbow ulnar collateral ligament (UCL) reconstruction is the amount of time required for recovery and rehabilitation. For example, for Major League Baseball pitchers, the average time to return to competition ranges from 13.8 to 20.5 months. Suture tape augmentation has shown the ability to provide additional soft tissue stability across other joints in the body. By providing an additional checkrein to the UCL reconstruction while the graft is healing, it may be possible to accelerate the rehabilitation process in overhead athletes and thus effect a quicker return to sports.

Purpose:

To compare elbow valgus stability and load to failure between UCL reconstruction with and without suture tape augmentation.

Study Design:

Controlled laboratory study.

Methods:

Fresh-frozen cadaveric elbows (N = 24) were dissected to expose the UCL. Medial elbow stability was tested with the UCL intact, deficient, and reconstructed utilizing the 3-strand docking technique with or without suture augmentation. A 3-N·m valgus torque was applied to the elbow, and valgus rotation of the ulna was recorded via motion-tracking cameras as the elbow was cycled through a full range of motion. After kinematic testing, reconstructed specimens were loaded to failure at 70° of elbow flexion.

Results:

UCL-deficient elbows demonstrated significantly greater valgus rotation when compared with intact and internally braced reconstructed elbows at every angle of flexion tested and when compared with unbraced UCL-reconstructed elbows at 50° to 120° of flexion (P < .05). There were no significant differences between intact and UCL-reconstructed elbows with and without suture augmentation at any flexion angle tested. When loaded to failure, unbraced reconstructed elbows failed at a significantly lower torque as compared with elbows with UCL reconstruction with suture tape augmentation (P < .01).

Conclusion:

In this cadaveric model, 3-strand UCL reconstruction with suture augmentation did not overconstrain the elbow throughout all flexion angles when compared with the native state and UCL reconstruction alone, while providing greater load to failure.

Clinical Relevance:

Suture tape augmentation may provide the additional strength necessary to accelerate rehabilitation after UCL reconstruction.