Comparison of biomechanical and histological roperties of three tendon suturing methods in suturing tendon ruptures of rats

Jiyou LI

ABSTRACT

BACKGROUND:

There are many kinds of suturing methods for curing hand extensor tendon rupture. But different methods present different clinical effects and the adhesion of tendon following operation is still a clinical difficulty.

OBJECTIVE:

To make a comparative study on the biomechanical properties and histological differences of 3 tendon suturing methods. DESIGN, TIME AND

SETTING:

A comparative observational animal experiment was completed in the Centralab of the First Clinical Collage of Harbin Medical University from April to June 2008. MATERIALS A total of 45 Wistar rats were randomly divided into 3 groups, namely, Tang method group, upgraded Kessler method group and Bunnell method group.

METHODS:

Under germ free condition, posterolateral achilles tendons of hide limbs of rats were cut open in S shape and their subcutaneous tissues were separated. Then, sharp transsection was performed to the achilles tendons of rats. At hour 24, week 1 and week 3 postoperatively, tendons of rats in the three groups were sutured with their corresponding methods, namely Tang method, upgraded Kessler method and Bunnell method. The sampling objects were the hind limbs of each rat, with the right ones undergoing biomechanical test and the left ones undergoing histological detection. MAIN OUTCOME

MEASURES:

The tensile strength (TS) and the histological change of the tendon rupture.

RESULTS:

At hour 24, week 1 and week 3, the TS of the three groups changed in the same direction, regardless of the tendon suturing method used, i.e. the TS of each group weakened during the early period and strengthened gradually during the later period. However, the tendon sutured by Tang method presented greater TS than the other two groups at hour 24 and week 1 postoperatively. At week 3, there is no difference of significance in TS among the three groups. In addition, the histological detection with HE staining showed pathological sections of great difference to the three groups at week 1 postoperatively, i.e. more granulation tissues formed in the group sutured with Tang method than in the other two groups, with more new vessels, less inflammatory cells and completely-expanded lumen of blood vessels in these granulation tissues.

CONCLUSION:

The Tang tendon suturing method results in faster healing and greater TS to the broken ends of tendons than the other two. Accordingly, it is more suitable for early functional exercise.