ACL primary transosseous repair in acute and chronic lesions is successful in specific cases with a proximal injury location and a good tissue quality. Functional restoration with resumption of the previous activity is possible and successful in a high percentage of these selected cases. Further research is needed to select the best indications and management for this conservative surgery.
A renewed interest is rising in the primary healing capacity of the anterior cruciate ligament (ACL), usually when approaching acute lesions. Literature is still lacking about primary ligament repair in chronic ACL-deficient knees with good quality of ligamentous tissue and a proximal lesion. In this prospective study we present an arthroscopic technique for ACL primary repair as a suitable choice for managing both acute and chronic ligament lesions, reporting outcomes.
From 2006 to 2017, 47 patients (21 females, 26 males) underwent a primary arthroscopic ACL transosseous repair with a cortical button fixation. Patients were included if they had a proximal avulsion tear and excellent tissue quality, confirmed to be adequate for repair during arthroscopy.
The mean age at time of surgery was 34 years (range 13 to 70). 11 patients (acute) underwent the repair within 3 weeks from injury, 36 patients (chronic) were treated after at least 4 weeks from trauma.
All the patients practiced sports activity before the trauma.
Clinical subjective outcomes were measured using the Knee injury and Osteoarthritis Outcome Score (KOOS), the subjective International Knee Documentation Committee (IKDC) and the Tegner Activity Scale. Objective results were evaluated using the objective IKDC score and determining the anterior stability with a KT-1000® arthrometer. Pre- and postoperative conditions were statistically compared using the Student t-test.
The mean follow-up was 6,7 years (range 1 to 11,5 years).
The KOOS score changed from a preoperative mean of 53,3 (SD 18,3) to a postoperative mean of 93,1 (SD 12,1). The Tegner scale showed a pre-injury mean of 6,7 (range 5 - 9) (SD 1,1) and a postoperative mean of 6,4 (range 4 - 9) (SD 1,3). The subjective IKDC increase from a 44,3 (SD 17,4) before surgery to a mean of 92,7 (SD 12,9) after the repair. After surgery, the objective IKDC score was A for all patients, as well as all the patients had less than 3 mm of increased anterior translation with the KT-1000® arthrometer. The pre- and postoperative results were statistically significantly different in KOOS scores, and both the subjective and objective IKDC scores (p<0,05).
Four patients underwent an ACL reconstruction for traumatic failure of the repair, of whom 1 patient after a primary acute lesion and 2 patients after a chronic tear repair. One patient quit sports activity at all. The mean time to return to sport was 8,4 months (range 4 to 24).
The ACL primary repair is a valid surgical option in specific cases, provided a good quality of ligamentous tissue and a proximal location of the lesion, in both acute and chronic ACL-deficient knees.
This technique consisting in re-tensioning the ACL through cortical fixation is effective and minimally invasive with excellent results and a failure rate of less than 10%.
Further research is needed to identify the best surgical indications for this procedure, to further reduce the revision incidence.