Reconstruction of the Medial Ulnar Collateral Ligament of the Elbow: Biomechanical Comparison of a Novel Anatomic Technique to the Docking Technique.

BACKGROUND

In recent years, understanding of the anatomy of the ulnar collateral ligament (UCL) has evolved, demonstrating that the insertional footprint of the UCL on the ulna is more elongated and distally tapered than previously described. Current UCL reconstruction configurations do not typically re-create this native anatomy, which may represent a potential area for improvement.

PURPOSE/HYPOTHESIS

The purposes of this study were (1) to describe a novel anatomic UCL reconstruction technique designed to better replicate the native UCL anatomy and (2) to biomechanically compare this with the docking technique. The hypothesis was that the ultimate load to failure for the anatomic technique would not be inferior to the docking technique.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 16 fresh-frozen cadaveric upper extremities (8 matched pairs) were utilized. One elbow in each pair was randomized to receive UCL reconstruction via the docking technique or the novel anatomic UCL reconstruction technique with palmaris tendon autograft. Following reconstruction, biomechanical testing was performed by applying valgus rotational torque at a constant rate of 5 deg/s until ultimate mechanical failure of the construct occurred. Maximal torque (N·m), rotation stiffness (N·m/deg), and mode/location of failure were recorded for each specimen.

RESULTS

The mean ultimate load to failure for elbows in the docking technique group was 23.8 ± 6.1 N·m, as compared with 31.9 ± 8.4 N·m in the anatomic technique group (

CONCLUSION

Ultimately, the anatomic UCL reconstruction technique demonstrated superior strength and resistance to valgus torque when compared with the docking technique, and this was comparable with that of the native UCL from prior studies. Increased initial strength may allow for earlier initiation of throwing postoperatively and potentially shorten return-to-play times.

CLINICAL RELEVANCE

Current UCL reconstruction techniques do not accurately reproduce the UCL insertional anatomy on the ulna. The novel anatomic technique described may result in more natural joint kinematics. This study demonstrated load-to-failure rates that are significantly higher than with the docking technique and consistent with the native ligament, as reported from previous studies. These findings may serve as a foundation for future clinical study and optimization of this technique.

Informations de copyright

© The Author(s) 2019.

Déclaration de conflit d'intérêts

One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by a research grant from Arthrex. C.L.C. has received educational support from Arthrex and hospitality payments from Arthrex and Zimmer Biomet. B.B. and J.K. are employed by Arthrex. D.W.A. has received consulting fees from Stryker and hospitality payments from Arthrex. J.S.D. has received consulting fees from Arthrex, Trice, Linvatec, DePuy, Wright Medical, and Merck Sharp & Dohme; has received research support from Arthrex; receives royalties from Linvatec and Wolters Kluwer Health; is a paid speaker/presenter for Arthrex; and has received hospitality payments from Horizon Pharma. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.