Five to seven years follow-up study after anterior cruciate ligament reconstruction

Authors:	Sundgren P, Svensson S, Physiotherapy Programme, Linköping University.
Tutor:	Areskog N-H, professor emeritus, Dept of Research and Development, Kalmar University College of Health Sciences.

Background
Injury to the ACL is the most common ligament disruption in the knee. It usually occurs in contact-sports, such as soccer, handball and icehockey, approximately 2/3 of all ACL-injuries in Sweden. The injury is either limited to the ACL or combined with injury to some other structure/s in the knee. Anterior cruciate ligament injuries often cause a marked antero-lateral instability, which gives a reduced ability to participate in sports and perform heavy labour. Knee-ligament injuries are considered to be serious since they reduce the passive stability of the joint.

Aim of the study
The aim of this study was to evaluate knee-function 5-7 years after ACL-reconstruction.

Materials and Methods
Inclusion criteria: ACL-reconstruction made at the Dept of Orthopaedic Surgery, County Hospital of Kalmar between 1988-91. Only reconstruction at time of surgery. Only one knee was operated at this occasion. A patellar-stripe reconstruction was used. Fiftytwo patients met these criteria and were called to the tests. Twentynine responded and were tested. The patients were tested with functional tests: one-legged hop for length, vertical-jump, balancetest, and clinical tests: Lachman test, anterior drawer, pivot shift and Stryker-arthrometer. These tests were supplemented with an interwiew including the Lysholm score and the Tegner activity score and some additional questions.

Results
The patients hopped significantly shorter (p=0.05) with the reconstructed leg than with the uninjured leg. No significant difference in balance between the two legs was found.

Thigh-girth was significantly smaller (p=0.02) in the operated leg than in the unoperated. Active flexion was significantly impaired (p=0.04) in the operated leg. No significant differences were however found in extension or passive flexion. All sagittal translation tests, except pivot shift, showed significantly greater translation on the operated side. Tegner activity score showed significantly decreased (p=0.03) activity levels compared to pre-injury levels. Lysholm score average was 84.8 points. Twelve of the 29 patients stated that the balance in the operated knee was impaired. Four had had to change profession due to the knee injury. Seventeen stated that they had achieved full function in their reconstructed knee.

Conclusions
Since pre-operative and immediately post-operative data are missing, nothing can be said about any improvement/deterioration. The results show that function in general is impaired in the reconstructed knee. Compared to other materials the results of the construction were good though stability and strength were impaired. Small impairments in active flexion do not necessarily impair function. The patients were satisfied with the results of the reconstruction. Seventyfive procent had good or excellent function (78 to 100 points in Lysholm score). The balance test used is not recomended, because of its insensitivity.

Key words: ACL, balance, function, joint-motion, long-term follow-up.