Primary Repair of Medial Collateral Ligament Tears With Suture Augmentation

Abstract

Background:

The medial collateral ligament (MCL) is considered to have superior healing and has classically been treated nonoperatively in low-grade MCL injuries. The MCL injury in the setting of concomitant anterior cruciate ligament (ACL) injury is usually treated with a delay of surgery to allow for nonoperative MCL treatment. Recent studies have shown that even with grade II MCL injury there may be residual laxity which may affect place greater strain on an ACL graft in the multi-ligamentous setting and can be corrected for with early primary repair of the MCL which also allows for early definitive treatment of concurrent ipsilateral ligamentous injuries.

Indications:

All patients are potential candidates given sufficient tissue quality for repair; however, this procedure is preferably performed acutely to avoid scarring, quadriceps strength loss, and allow for early intervention to any concurrent ipsilateral ligamentous knee injury. This technique may be performed on both proximal and distal MCL injuries with the same anchor positioning in either case.

Technique Description:

The torn superficial and deep MCL are sutured using a Bunnell-type pattern. The superficial proximal MCL is then fixed to its anatomic footprint using a suture anchor preloaded with an internal suture tape augmentation. A second small incision is made over the tibial insertion of the MCL and a passing suture is channeled from the distal to proximal incision under a skin bridge to retrieve the suture tape. The suture tape is then deployed with appropriate tensioning to the anatomic distal insertion point of the superficial MCL using a second suture anchor.

Results:

There is currently no published data regarding patient outcomes after MCL primary repair with suture augmentation. Our preliminary unpublished data with 49 patients treated with this technique and a variety of concomitant ligamentous injury with average follow-up of 1.7 years showed no MCL repair failures. Four patients experienced more than 10° of flexion range of motion loss, and 3 had residual valgus laxity of grade 1 at 0° and 30° of flexion.

Conclusion:

Primary MCL repair provides a minimally invasive treatment option for medial laxity, while the suture augmentation allows for early range of motion. Furthermore, this approach avoids delayed definitive surgical intervention of concomitant ligamentous injuries in the setting of combined multi-ligamentous injuries.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

We present to you our technique of primary repair of the medial collateral ligament with suture augmentation.

These are our disclosures.

The medial collateral ligament (MCL) is commonly injured at the same time as the anterior cruciate ligament (ACL), with up to 80% of grade III Fetto and Marshall MCL injuries occurring in the setting of an ACL injury. The MCL is considered to have superior healing capacity to the ACL which has led to the consensus that grade I MCL injuries should be treated conservatively. Operative management of high-grade MCL injuries aims to prevent significant residual laxity, avoid delay of surgery for treatment of a concomitant ACL injury, and decrease strain on a healing ACL construct, with several authors reporting excellent outcomes after MCL repair with suture augmentation or MCL reconstruction.

The patient is a 31-year-old male professional rugby player who suffered a hard valgus impact to his left knee during a match 3 weeks prior; he was unable to continue playing. His physical examination was limited due to pain, although we noted 2-3+ laxity to valgus stress at full extension and 30°. Lachman exam was positive, however, the patient was splinting. He was stable to varus and posterior stress and had positive lateral joint line tenderness.

Here, we see representative slices from the magnetic resonance imaging (MRI), confirming a proximal tear of both the superficial and deep MCL with what appears to be good tissue quality in addition to at least a high-grade partial proximal ACL tear with good tissue quality.

Indications for MCL repair include grade II or III proximal or distal avulsion tears of sufficient tissue quality; however, there is some controversy on whether grade II tears should be treated surgically. All age groups are candidates for MCL repair. Tears eligible for repair include isolated injuries of the MCL and MCL injuries in the multi-ligamentous knee injury setting with the most common combination being the ACL-MCL concurrent injury. Contraindications to repair include tears with poor tissue quality unable to hold stitches.

The patient returned to clinic 2 weeks post-injury where his pain was improved. He now had 100° of range of motion (ROM) with an unchanged laxity exam, although he was still somewhat splinting. As mentioned previously, he had a proximal tear of the MCL and ACL in addition to a lateral meniscus tear. Surgery was planned for 1 week later with a surgical plan to perform an examination under anesthesia, ACL repair versus reconstruction, MCL repair versus augmentation, and lateral meniscal repair versus meniscectomy.

The patient positioning for surgery is similar to ACL reconstruction. We are in the supine position with a tourniquet high on the thigh. The operative leg is prepped and draped as for ACL reconstruction.

An examination under anesthesia revealed 0° to 140° ROM, 3+ laxity to valgus stress at full extension and 30°, a grade 2B Lachman, and a 1+ pivot shift. Not depicted here was stability to varus and posterior stress.

The arthroscopic portion of the case allowed for primary repair with suture augmentation of a proximal ACL tear along with a partial lateral meniscectomy.

At this point our attention was turned to the MCL with dissection over the medial condyle with vigilance to protect the nerve. After dissecting past layer 1, we are able to visualize the deep MCL fibers shown here and the superficial MCL fibers shown here avulsed off its femoral origin.

The posterior oblique ligament, superficial and deep MCL are sutured in a Bunnell-type pattern using nonresorbable sutures as shown here.

The repair sutures are then loaded through the eyelet of a Vented BioComposite suture anchor with a preloaded FiberTape which will function as the internal brace to provide early stability. The suture anchor is then deployed in standard fashion just posterior to the medial epicondyle at the natural insertion point of the superficial MCL while the repair stitches are appropriately tensioned with the knee in 30° of flexion.

An incision is made over the distal insertion of the superficial MCL with dissection through layer 1.

A clamp is used to place a passing suture to shuttle the FiberTape under the skin bridge toward the distal insertion point.

The FiberTape is loaded onto a second Vented BioComposite anchor and partially deployed 6 cm distal to the joint line just proximal to the hamstring insertion and centered in the ligament from anterior to posterior. After the knee is ranged to confirm that the knee was not captured and there is still full flexion ROM, the anchor is fully deployed with the knee in 30° of flexion.

With the completion of the procedure, a final assessment is made to make sure we maintained full ROM and attained stability to valgus stress and Lachman exam.

At 5-week follow-up, the patient was found to have full ROM, stability to laxity examination, and was able to run, cut, and jump effectively in the hallway.

Some pearls to avoid complications during this procedure. Assess for other potentially injured ligaments nearby such as the Medial Patellofemeral Ligament (MPFL), deep MCL, and posterior oblique ligament (POL) which should be addressed as necessary. The repair stitches should be assessed for overtensioning before deploying the suture anchor. The suture anchor should then be partially deployed initially to allow for ranging of the knee to assess whether the joint capsule was captured. Finally, suture anchors should be deployed with the knee in 30° of flexion to avoid overconstraint of the knee.

Regarding the postoperative management of these patients, we focus on attaining early mobilization, preventing stiffness, and normalizing gait. While other concomitant ligamentous injuries affect the exact rehabilitation protocol, our general approach is to use a knee brace for the first 4 weeks with weight bearing as tolerated. At first, the brace is locked in extension when ambulating until return of volitional quadriceps control, at which point we will unlock it. Crutches are only used if there was a meniscal repair or there were other ligamentous injuries within the knee. We start our patients on gentle ROM and strengthening exercises in the first few days and an accelerated ACL rehabilitation program initiated at 4 weeks. Patients with other significant ligamentous injuries receive extended rehabilitation as needed to avoid loss of ROM.

Regarding return-to-sport guidelines, a return to pivoting sports is generally based upon sports-specific assessments and any other major ligamentous injury. In the case of isolated MCL injury, the majority return to sport by 3 months postoperatively. It is important that full ROM has been obtained and that the leg has sufficient muscle strength relative to the contralateral limb.

There are currently no published data regarding patient outcomes after MCL primary repair with suture augmentation. On retrospective review of our database, we have identified 49 patients treated with this technique and a variety of concomitant ligamentous injury. Our average follow-up is 1.7 years. No patients experienced a failure of the MCL repair, with 4 patients experiencing more than 10° of flexion ROM loss with no loss of extension ROM. Three patients had residual valgus laxity of 1+ at 0° and 30° of flexion which did not progress. All 4 patients with more than 10° of flexion ROM loss had multiple other ligamentous and meniscal repairs beyond the ACL/MCL combination. Two of the 3 patients with residual valgus laxity were aged 18 and below. The majority of patients in the series were above the age of 18, making it difficult to draw conclusions as to whether pediatric patients may require a more robust reconstruction technique. Our experience has been that this technique allows for early definitive intervention for MCL tears regardless of whether this injury is in the isolated or multi-ligamentous setting.

Thank you for your attention.