Summary

The purpose of this study was to determine regeneration pattern of period through ultrasound and compare the correlation between regeneration pattern in ultrasound and muscle strength and functional performance test.

Abstract

Introduction

After Anterior Cruciate Ligament Reconstruction in several studiess have reported the regeneration of semitendinosus tendon. However, research for the regeneration pattern of period and function is not enough. The purpose of this study was to determine regeneration pattern of period through ultrasound and compare the correlation between regeneration pattern in ultrasound and muscle strength and functional performance test.

Material And Method

By prospective method, From April 2013, We enrolled 56 patients who undergoing anterior cruciate ligament reconstruction using the semitendinosus tendon autograft, 34 patients were observed for more than 6 months were eligible. The patients underwent multiple ligament or meniscus transplantation or HTO , etc. at the same time were excluded. Ultrasound was continuously performed before surgery and at 1month, 3months, 6months postoperatively. We measured regeneration degree and migration to the proximal extent of musculotendinous junction based on the tibia plateau. Flexor strength, extensor strength using Biodex System III dynamometer and functional performance test(one-leg-hop test, co-contraction, shuttle run, and carioca tests) were evaluated at 3months, 6months postoperatively.

Result
In the 34 patients observed for more than 6 months(26 male, 8 female), semitendinosus tendon regeneration has been observed in 26 patients (76.4%) at 6 months postoperatively. The average length of semitendinosus tendon is 5.77cm and the average thickness semitendinosus tendon is 0.173 cm2 before surgery. Musculotendinous junction migrated to the proximal 3.69cm on average and the average thickness was increased to 0.243 cm2 at 1week postoperatively. The hematoma was observed in harvesting areas in 20 patients at 1month postoperatively and semitendinosus tendon regeneration was observed in all these patients at 6months postoperatively. Semitendinosus tendon regeneration did not occur in 8 patients among 14 patients hematoma did not occur. The average length of regenerated semitendinosus tendon is 9.94cm, 11.07 respectively and the average thickness regenerated semitendinosus tendon is 0.497 cm2, 0.438 cm2 respectively at 3months, 6months postoperatively. Musculotendinous junction was confirmed that the recession and move to the proximal significantly(P=0.34) in non-regeneration group. No differences were found between two groups in terms of muscle strength and functional results(P=0.705).

Conclusion

Hematoma presence in harvesting area is very important role in semitendinosus tendon regeneration after anterior cruciate ligament reconstruction using the semitendinosus tendon autograft and We were able to verify that whether semitendinosus tendon regeneration up to six months postoperatively does not affect muscle strength and functional results. Semitendinosus regeneration is considered to be nearly complete between 3 and 6 months postoperatively because there is almost no difference in the regeneration pattern between 3 months and 6 months postoperatively therefore hemstring specific exercise and acelerative rehabilitation are considered to be performed between 3 and 6 months postoperatively.