Purpose: The purpose of this study was to clarify the fate of intra-articularly transplanted multistranded hamstring tendon grafts used for anterior cruciate ligament (ACL) reconstruction.
Type of study: Consecutive samples.
Methods: The subjects were 153 patients (156 knees) with a mean age of 24 years, who had been evaluated as experiencing clinical success. The patients consented to undergo second-look arthroscopy after ACL reconstruction with multistranded autogenous hamstring tendon grafts at 5 to 51 months previously. Ninety-six knees were surgically treated with the single-socket procedure, and the remaining 60 were treated with the bisocket procedure. None of the patients complained of instability of the index knee. The mean side-to-side difference at manual-maximum force in anterior displacement by KT-1000 on 107 patients was 1.2 +/- 1.1 mm (-1 to 4 mm). Arthroscopic evaluation was performed focusing on tension and thickness dividing into 3 groups based on the postoperative period. The chi-square and Mann-Whitney U tests were used for statistical analysis.
Results: A total of 139 grafts (89%) were evaluated as taut and 17 (11%) as mildly lax or lax. Fifty-three (34%) showed some partial tear, and the other 103 (66%) appeared thick without partial tear. The percentage of mildly lax or lax grafts in the group of patients older than 2 years was higher than that in patients younger than 1 year, and no significant difference was found among the groups in the percentage of partially torn grafts. The patients with mildly lax or lax grafts showed statistically higher KT values, while those with partially torn grafts did not. No statistically significant difference was seen in any of these findings between the 2 procedures, although the bisocket procedure tended to show better tension or thickness.
Conclusions: Arthroscopically, 11% of the hamstring ACL grafts showed looseness and 34% had partial tear in the clinically successful knees.
Level of evidence: Level IV in therapeutic studies investigating the results of treatment.