title: Ligament repair around the knee with suture tape augmentation
Creators: name: Hopper, Graeme Philip
Publisher: name: University of Glasgow
Year: 2020
Subjects: subject: Knee, ACL, ALL, PCL, MCL, PLC, MPFL, ligament repair, augmentation.

description: Ligament repair around the knee was widely used in the 1970s and 1980s but with mixed outcomes. High failure rates at mid-term follow-up and the success of ligament reconstruction resulted in its demise. Reconstruction using autograft has been the gold standard surgical treatment since the 1990s. Nonetheless, ligament reconstruction is not without its complications including post-traumatic osteoarthritis, loss of proprioception and graft site morbidity. Indeed, it has been reported that 69% of patients undergoing anterior cruciate ligament (ACL) reconstruction with hamstring autograft had radiologically detectable osteoarthritis 15 years postoperatively. Furthermore, graft site morbidity including knee flexor weakness with hamstring grafts and anterior knee pain with patellar tendon grafts is commonly reported. Likewise, loss of the ACL remnant during ACL reconstruction surgery has been shown to reduce proprioception recovery postoperatively which could have detrimental effects for rehabilitation and be associated with contralateral ruptures. Recently, an enhanced understanding of ligament healing and an improvement in arthroscopic instrumentation, suture materials, imaging techniques and rehabilitation has led to a renewed interest in ligament repair. Extra-articular ligaments that can naturally heal with nonoperative management such as the medial collateral ligament (MCL) form a fibrin clot between the ends of the torn ligament which provides a scaffold to permit the MCL to heal. Intra-articular ligaments such as the ACL do not allow the formation of this clot therefore there is no scaffold to permit the ACL to heal. As a result, modern techniques have concentrated on providing this scaffold or an augment to support intra-articular ligaments during the healing phase. Additionally, modern suture techniques and arthroscopic instrumentation allows simpler repair of the ligaments in addition to the scaffold or augment. Furthermore, recent insights into the structure and function of the anterolateral ligament (ALL) and the posterolateral corner (PLC) in providing rotational control of the knee has led to a renewed interest in supplementary techniques as these ligaments are often part of a multiligament knee injury. Internal bracing involves the augmentation of a ligament repair with suture tape which acts as a secondary stabilizer and gives the ligament a protective environment to heal and allows early mobilization to aid rehabilitation. The suture tape is FiberTape® (Arthrex) which is an ultra-high strength 2mm width tape, consisting of a long chain ultra-high molecular weight polyethylene (UHMWPE). Its ends are tapered to FiberWire® (Arthrex) for easy suture passage which is the same material and has a similar structure. It has a high tensile strength and stiffness in comparison to other similar suture materials. In addition, it has extensive biocompatibility proven through animal and clinical testing. Finally, the multi-strand long chain UHMWPE results in an increased abrasion resistance in comparison to other similar sutures. Internal bracing of the anterior cruciate ligament, anterolateral ligament, posterior cruciate ligament (PCL), medial collateral ligament, posterolateral corner and medial patellofemoral ligament (MPFL) is described. The surgical techniques are explained in detail along with illustrations and the advantages and disadvantages of the techniques are discussed. We hypothesized that internal bracing of these ligaments would demonstrate significant improvements in patient-reported outcome measures that would be comparable to reconstruction techniques described in the literature. Moreover, the additional rotational stability provided by repair of the anterolateral ligament would decrease the ACL re-rupture rate in comparison to isolated ACL repairs. Patients in each group were evaluated prospectively using patient-reported outcomes measures including the KOOS, WOMAC, Visual Analog Pain Scale (VAS) VR-12 and the Marx Activity scale. This data was collected preoperatively and at 12, 24 and 60 months postoperatively. Additionally, a standard questionnaire was completed to ask the patients who did not have any further surgery about their overall satisfaction with regards to reducing pain, improving movement, resuming normal function and resuming sport. Patients were also contacted by email/telephone at the time of this analysis to seek out any postoperative complications including any further surgery on the ipsilateral and contralateral knee. The anterior cruciate ligament group was followed up for a minimum of 5 years and the other ligament groups for a minimum of 2 years. Encouraging results are confirmed in all of the ligaments around the knee. The mean KOOS and WOMAC scores increased significantly and the VAS score and VR-12 physical scores improved significantly in all of the groups. 6 patients had an ACL re-rupture (17.6%) after isolated ACL repair. These patients were found to be younger and have higher initial Marx activity scores than the rest of the cohort. A combined ACL and ALL repair with internal brace augmentation in these higher risk patients reduced the ACL re-rupture rate to 5.3%. As a result, a treatment algorithm for ACL ruptures and the requirements for additional ALL rotational support is produced. As far as we are aware, these are the first cohorts of patients with minimum 5-year outcomes of ACL repair with internal brace augmentation and patients with minimum 2-year outcomes undergoing a combined ACL repair and ALL repair, PCL repair, MCL repair, PLC repair or MPFL repair with internal brace augmentation. In conclusion, it is indicated that internal bracing gives surgeons an alternative technique to traditional reconstructions and avoids the need for a graft thereby preventing donor site morbidity whilst also preserving the proprioceptive fibres of the ligament. Nonetheless, further clinical studies are necessary with larger patient numbers and longer follow-up as well as studies with a higher level of evidence to further assess these encouraging early results of ligament repair with internal bracing around the knee.