Midterm Outcomes, Complications, and Return to Sports After Medial Collateral Ligament and Posterior Oblique Ligament Reconstruction for Medial Knee Instability: A Systematic Review

Background: In cases of multiple ligaments or medial collateral ligament (MCL) reconstruction, restoring the native anatomy of the posterior oblique ligament (POL) to address chronic valgus instability has been attracting increased attention. Purpose: To review the current literature on postoperative outcomes, complications, and return to sports after superficial MCL-POL (sMCL-POL) reconstruction to restore medial knee integrity. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was conducted based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Two independent reviewers searched the PubMed, Scopus, Embase, and Cochrane Library databases using the terms “posterior oblique ligament,” “posteromedial corner of the knee,” and “reconstruction.” Included were studies that reported postoperative clinical and functional outcomes in patients who had undergone a combined sMCL-POL reconstruction for medial knee instability. The authors evaluated surgical technique, rehabilitation protocol, postoperative outcomes (Lysholm, International Knee Documentation Committee [IKDC], and Tegner scores and valgus stress radiograph), and return to sports and complication rates across the included studies. Results: A total of 6 studies were reviewed. The cohort consisted of 199 patients (121 men and 78 women), with a mean age of 32.7 ± 3.9 years (range, 27.4-36.6 years). The Lysholm and IKDC scores improved from pre- to postoperatively (Lysholm, from 67.2 ± 20.4 to 89.4 ± 3; IKDC, from 45.8 ± 2.1 to 84.8 ± 7.5). The Tegner score produced satisfactory results, from a preoperative mean of 3.3 ± 2.4 to 6.3 ± 0.9 postoperatively. The medial joint opening on valgus stress radiographs ranged from 7.5 ± 1.1 mm preoperatively to 3 ± 3.1 mm postoperatively. After passing activity-specific functional and clinical tests, 88% to 91.3% of the patients were reported to have returned to recreational sports within 6 to 12 months postoperatively, whereas 10% of the patients developed postoperative complications. Conclusion: Satisfactory clinical and functional outcomes, a high rate of return to recreational sports, and a low rate of postoperative complications were reported after an sMCL-POL reconstruction to restore medial knee integrity.

Posterior oblique ligament of the knee: state of the art

The posterior oblique ligament (POL) is the predominant ligamentous structure on the posterior medial corner of the knee joint. A thorough understanding of the anatomy, biomechanics, diagnosis, treatment and rehabilitation of POL injuries will aid orthopaedic surgeons in the management of these injuries. The resulting rotational instability, in addition to valgus laxity, may not be tolerated by athletes participating in pivoting sports. The most common mechanism of injury – accounting for 72% of cases – is related to sports activity, particularly football, basketball and skiing. Moreover, three different injury patterns have been reported: those associated with injury to the capsular arm of the semimembranosus (SM), those involving a complete peripheral meniscal detachment and those involving disruption of the SM and peripheral meniscal detachment. The hallmark of an injury related to POL lesions is the presence of anteromedial rotatory instability (AMRI), which is defined as ‘external rotation with anterior subluxation of the medial tibial plateau relative to the distal femur’. In acute settings, POL lesions can be easily identified using coronal and axial magnetic resonance imaging (MRI) where the medial collateral ligament (MCL) and POL appear as separate structures. However, MRI is not sensitive in chronic cases. Surgical treatment of the medial side leads to satisfactory clinical results in a multi-ligamentous reconstruction scenario, but it is known to be associated with secondary stiffness. In young patients with high functional demands, return to sports is allowed no earlier than 9–12 months after they have undergone a thorough rehabilitation programme. Cite this article: EFORT Open Rev 2021;6:364-371. DOI: 10.1302/2058-5241.6.200127

Combined Anterior Cruciate Ligament Reconstruction Revision and Double-Bundle Medial Collateral Ligament and Posterior Oblique Ligament Reconstruction

Background: Nonsurgical treatment of concomitant medial collateral ligament (MCL) in the setting of anterior cruciate ligament reconstruction (ACLR) increases the risk of graft failure. Few published cases of medial complex reconstruction combined with ACLR with no clear consensus on the optimal technique to treat these complex injuries. Indications: A female patient aged 41 years, with failure of ACLR in 2009 and 2 revisions in 2013 and 2014, associated with concomitant nontreated MCL and posterior oblique ligament (POL) injury. Physical examination showed valgus test laxity grade III at 30° of knee flexion and at full extension, with Lachman and pivot-shift test grade III. Imaging showed normal long-leg standing axis with 10° posterior tibial slope on radiograph, and associated MCL and POL injury on magnetic resonance imaging. Technique Description: ACLR and anterolateral tenodesis using the fascia lata leaving its distal insertion on the Gerdy tubercle, with double-stranded contralateral gracilis, was completed. A new femoral tunnel was made from outside to inside, with preservation of the previous tibial tunnel. The transplant was fixed with 2 interference screws. Second, the contralateral semitendinous autograft was used for MCL and POL reconstruction. A single strand of the graft was used for femoral fixation created on femoral epicondyle to cover MCL and POL origins, and double strands were used for distal fixation of MCL at the level of hamstring insertion and POL at the posteromedial corner of medial tibial plateau. The graft was secured with 3 interference screws at 30 knee flexion for MCL and full extension for POL. Results: The results include favorable functional and clinical outcome with improvement in the anteroposterior and rotatory knee stability at mid-term follow-up. Lateral extra-articular tenodesis in supplementing ACLR controls internal tibial rotatory knee stability. Double-bundle reconstruction of MCL and POL improved both valgus and anteromedial rotatory instability by restraining external rotation. Discussion/Conclusion: Surgeons should consider the need for surgical treatment of concomitant MCL injury to prevent chronic valgus laxity and increased strain on the anterior cruciate ligament (ACL) graft, potentially increasing the risk of ACLR revision. Our described technique offers a safe method for ACLR and lateral tenodesis with an advantage to avoid tunnel convergence, and medial stabilization to restore native valgus and rotatory stability and prevent increased stress on ACL graft.

Development and Assessment of Novel Multiligament Knee Injury Reconstruction Graft Constructs and Techniques

Multiligament knee injury (MLKI) typically requires surgical reconstruction to achieve the optimal outcomes for patients. Revision and failure rates after surgical reconstruction for MLKI can be as high as 40%, suggesting the need for improvements in graft constructs and implantation techniques. This study assessed novel graft constructs and surgical implantation and fixation techniques for anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), posterior medial corner (PMC), and posterior lateral corner (PLC) reconstruction. Study objectives were (1) to describe each construct and technique in detail, and (2) to optimize MLKI reconstruction surgical techniques using these constructs so as to consistently implant grafts in correct anatomical locations while preserving bone stock and minimizing overlap. Cadaveric knees (n = 3) were instrumented to perform arthroscopic-assisted and open surgical creation of sockets and tunnels for all components of MLKI reconstruction using our novel techniques. Sockets and tunnels with potential for overlap were identified and assessed to measure the minimum distances between them using gross, computed tomographic, and finite element analysis-based measurements. Percentage of bone volume spared for each knee was also calculated. Femoral PLC-lateral collateral ligament and femoral PMC sockets, as well as tibial PCL and tibial PMC posterior oblique ligament sockets, were at high risk for overlap. Femoral ACL and femoral PLC lateral collateral ligament sockets and tibial popliteal tendon and tibial posterior oblique ligament sockets were at moderate risk for overlap. However, with careful planning based on awareness of at-risk MLKI graft combinations in conjunction with protection of the socket/tunnel and trajectory adjustment using fluoroscopic guidance, the novel constructs and techniques allow for consistent surgical reconstruction of all major ligaments in MLKIs such that socket and tunnel overlap can be consistently avoided. As such, the potential advantages of the constructs, including improved graft-to-bone integration, capabilities for sequential tensioning of the graft, and bone sparing effects, can be implemented.

The bone attachments of the medial collateral and posterior oblique ligaments are defined anatomically and radiographically

Purpose To define the bony attachments of the medial ligaments relative to anatomical and radiographic bony landmarks, providing information for medial collateral ligament (MCL) surgery. Method The femoral and tibial attachments of the superficial MCL (sMCL), deep MCL (dMCL) and posterior oblique ligament (POL), plus the medial epicondyle (ME) were defined by radiopaque staples in 22 knees. These were measured radiographically and optically; the precision was calculated and data normalised to the sizes of the condyles. Femoral locations were referenced to the ME and to Blumensaat’s line and the posterior cortex. Results The femoral sMCL attachment enveloped the ME, centred 1 mm proximal to it, at 37 ± 2 mm (normalised at 53 ± 2%) posterior to the most-anterior condyle border. The femoral dMCL attachment was 6 mm (8%) distal and 5 mm (7%) posterior to the ME. The femoral POL attachment was 4 mm (5%) proximal and 11 mm (15%) posterior to the ME. The tibial sMCL attachment spread from 42 to 71 mm (81–137% of A-P plateau width) below the tibial plateau. The dMCL fanned out anterodistally to a wide tibial attachment 8 mm below the plateau and between 17 and 39 mm (33–76%) A-P. The POL attached 5 mm below the plateau, posterior to the dMCL. The 95% CI intra-observer was ± 0.6 mm, inter-observer ± 1.3 mm for digitisation. The inter-observer ICC for radiographs was 0.922. Conclusion The bone attachments of the medial knee ligaments are located in relation to knee dimensions and osseous landmarks. These data facilitate repairs and reconstructions that can restore physiological laxity and stability patterns across the arc of knee flexion.