[Case-control study on remnant-preserving strategy for preservation and reconstruction of anterior cruciate ligament]

To investigate and compare the clinical efficacies of remnant-preserving and remnant-non-preserving, remnant-non-preserving remnant segment preserving and remnant root preserving with anterior cruciate ligament reconstruction.

From March 2014 to December 2017, 204 patients with anterior cruciate ligament (ACL) injuries were treated by single-bundle ACL reconstruction with hamstring tendon autograft. According to the different methods of remnant preservation, the procedures were divided into remnant segment preserving group (A), remnant root preserving group (B), and remnant-non-preserving group (C). There were 37 males and 39 femalesin group A aged from 16 to 43 years old with an average of (28.80±5.41) years old. The time from injury to operation ranged from 2 to 11 weeks with an average of (3.68±1.04) weeks. In group B, there were 39 males and 25 females aged from 18 to 41 years old with an average of (28.42±5.60) years old. The time from injury to operation ranged from 2 to 10 weeks with an average of (3.36±1.68) weeks. In group C, there were 37 males and 27 females aged from 18 to 43 years old with an average of (29.10±6.11) years old. The time from injury to operation ranged from 3 to 11 weeks with an average of (3.54±1.46) weeks. The range of motion (ROM) of the knee was used to assess the range of extension and flextion of the knee at pre-operation and 24 months after operation. Lysholm score and the international knee documentation committee (IKDC) score were used to assess the knee function. The differences among three procedures were judged by comparing among the three groups at 6, 12 and 24 months postoperatively.

All incisions got a one stage healing, and no complications, such as vascular injury, nerve damage and articular infect or the like, occurred. All the patients were followed up, and the follow-up duration of group A ranged from 24.00 to 45.96 months with a mean of (35.52±14.40) months;the follow up duration of group B ranged from 27.96 to 48.00 months with a mean of (37.56±10.68) month;and the follow up duration of group C ranged from 24.00 to 66.00 months with a mean of (37.08±13.44) month. There were no significant differences in follow up time among three groups (P>0.05). Six months after operation, Lysholm score 80.74±3.14 and IKDC score 79.92±3.44 in group A were higher than those in group B 80.74±3.14 and 78.21±4.63, and higher than those in group C 79.22±3.63 and 76.63±3.80 (P<0.05);12 months after operation, Lysholm score 89.84± 5.13 and IKDC score 87.90±3.93 in group A were higher than those in group B 85.74±6.04 and 83.62±5.64, and higher than those in group C 82.83±3.43 and 79.21±4.04(P<0.05).

Compared with remnant-non-preserving group, the residual tissue of anterior cruciate ligament is preserved, which is conducive to promote the healing and remodeling of tendon graft and accelerate the recovery of joint function. Proper fixation of residual tissue and restoration of its tension are the key factors affecting the postoperative efficacy.