ACL suturing using dynamic intraligamentary stabilisation showing good clinical outcome but a high reoperation rate: a retrospective independent study

PURPOSE: Most of the clinical outcome studies dealing with ACL repair are from the developer's perspective. It is a fact that these developer-initiated studies tend to interpret the results rather in favour than against their developed technique or product. Hence, it was the purpose of the present independent investigator-initiated study to investigate the clinical and radiological outcomes as well as failure rate of patients who underwent an ACL suture using dynamic intraligamentary stabilisation device in a specialised independent knee clinic. METHODS: A retrospective study was performed on prospectively collected data of 26 patients (28 ± 9 years, range 18-50 years; male/female = 17:9) who underwent biologically augmented ACL suture using dynamic intraligamentary stabilisation. Mean time from ACL injury was 15 ± 5 days (range 4-25 days). In addition, in seven (27%) patients a medial meniscus refixation and in four (15%) patients a lateral meniscus refixation was done for associated meniscal lesions. All patients were clinically and radiologically followed up at 6 weeks, 3 and 12 months after ACL surgery using the Tegner and Lysholm score as well as IKDC score. Adverse events such as ACL failure, arthrofibrosis, pain > 3 on a visual analogue scale as well as the need and type of revision surgery were noted. RESULTS: Four patients (15%) suffered from an ACL retear due to another adequate trauma during follow-up time. In six patients (23%), an arthrofibrosis (extension deficit of > 10° or flexion deficit > 20°) was noted. In five of those six patients, an arthroscopic arthrolysis was performed. Three patients also complained about pain VAS > 3. In nine (35%) patients, superfluous ACL scar tissue and the DIS device including the polyethylene suture and the DIS screw were removed, and in another two (8%) patients, the DIS screw only was removed. In two patients, a partial meniscectomy was performed due to a non-healed meniscal suture. The median Tegner score was 8 (range 6-10) before injury and 7 (range 3-10) at last follow-up (p < 0.001). The mean Lysholm score before surgery was 28 ± 14 and 94 ± 11 at last follow-up (p < 0.001). At last follow-up, 14 patients (66%) showed a normal total IKDC score (A) and 4 patients (19%) were nearly normal (B) and 2 patients (10%) were slightly abnormal (C) and one patient (5%) was entirely abnormal (p < 0.001). CONCLUSION: ACL suturing using the dynamic intraligamentary stabilisation device showed satisfying clinical results at 12-month follow-up. However, a retear rate of 15% and a reoperation rate of 35% due to retear or arthrofibrosis appear rather high. These results highlight the importance of adequate patient selection and the delicacy of the surgical procedure. LEVEL OF EVIDENCE: Retrospective case series, Level IV.