Medial Ulnar Collateral Ligament Reconstruction: A Dual Docking,4-Ply Reconstructive Technique

Abstract

Background:

Ulnar collateral ligament injuries are common in the overhead-throwing athlete as the anterior band of this ligament is the primary soft tissue static stabilizer to valgus stress during a throwing motion. Various surgical techniques have been described over the past 30 years to address these injuries including Jobe, modified Jobe, docking, 3-stranded docking, Graftlink, and anatomic repairs with good to excellent results. Nevertheless, modifications to these techniques may increase the strength and survival of the reconstruction, which may expedite and optimize postoperative rehabilitation and return to play.

Indications:

This is a reproducible technique that provides excellent outcomes. We believe a 4-ply construct, with the addition of a high tensile strength suture tape, may provide superior biomechanical properties compared to other reconstructive techniques. Biomechanical testing for this technique is currently underway.

Technique Description:

Medial ulnar collateral ligament reconstruction using a gracilis autograft passed from proximal to distal, secured at the ulna with a cortical button tension loop construct, and then repassed from distal to proximal with the addition of a high strength suture in parallel to function as an internal brace. Together, this creates a reinforced, 4-ply, ulnar collateral ligament reconstruction with excellent tensile strength. Other advantages of this technique are that it avoids bony bridge fracture between ulnar tunnels, it preserves ulnar bone stock, creates a more anatomic insertion at the sublime tubercle and provides a simple method to tension the entire graft construct.

Results:

The expected outcomes from this procedure are consistently positive with recent literature reporting greater than 90% of patients having an excellent outcome and over 80% of overhead athletes returning to sport at or above previous level.

Conclusion:

This specific technique provides a rigid, high-tensile strength reconstruction with excellent outcomes and a high percentage of return to play. Additionally, this technique avoids various technical pitfalls by utilizing cortical button suspensory fixation at the ulna which minimizes complications such as ulnar tunnel conversion and iatrogenic injury to the ulnar nerve when drilling posterior to the sublime tubercle as is necessary with other techniques.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

This is a presentation of a medial ulnar collateral ligament reconstruction using a dual docking 4-ply reconstruction of a gracilis autograft.

There are no disclosures relevant to this surgical technique.

Medial ulnar collateral ligament (UCL) injuries are common in young overhead throwing athletes. Multiple surgical techniques have been proposed with excellent outcomes and return to sport.

Our reconstruction technique creates a 4-ply construct with the addition of a high strength suture to function as an internal brace, which may be biomechanially superior at time zero to other techniques. Importantly, biomechanical testing for this surgical technique is currently underway. We adopted this technique to avoid bony bridge fracture between ulnar tunnels, preserve bone stock and real estate in the ulnar, create a more anatomic insertion of the UCL at the sublime tubercle, and provide a simple method to tension the graft. An important consideration when emplying this technique is implant cost.

A typical case for performing for performing this technique is a 17-year-old male elite high school pitcher with 3 months of insidious medial-sided elbow pain. He noticed decreased velocity in his fast ball in the past few months and early fatigue to his elbow during recent games. Last week, he felt a sharp pain and pop along the medial aspect of his elbow while throwing a pitch and was unable to continue playing.

A typical physical examination revealed full elbow range of motion but with tenderness along the medial epicondyle in addition to pain with valgus stress. Magnetic resonance imaging (MRI) revealed a complete midsubstance tear of the medial UCL.

There is surgical indication for this patient as that he is an elite athlete with multiple scholarship offers and with plans to continue pitching at a high level.

Patient positioning for this surgical technique is supine positioning on a regular bed with the hand table placed on the operative side. Sterile tourniquet is placed on the upper portion of the operative extremity.

Pearls and pitfalls for this surgical technique are as follows: Always identify and protect ulnar nerve. Do not dilate the humeral tunnels excessively to avoid blowing out bony bridge between apertures. An ideal graft length is 200-220 mm. Aim dorsal and distal when creating ulnar socket to avoid injury to the proximal radioulnar and ulnohumeral joints, respectively. Tension graft in neutral or varus elbow alignment at 30-40° of flexion with forearm in full supination.

Postoperative management and return to sport protocol is that the posterior slab splint and sling are discontinued 1 week after surgery, and physical therapy is started with gentle active assisted and active range of motion. By week 6, patients should have achieved full range of motion in all planes. At week 6-16, patients focus on resistance training for elbow extension/flexion, wrist extension/flexion, and rotator cuff and periscapular strengthening exercises. At week 16, patients begin a formal return to throwing program by beginning to throw at 45 ft for 10 minutes (3-4x/week with rest day in between). Proper mechanics and follow through are evaluated and reviewed. At week 24, 90-foot throwing is allowed for 15 minutes. At week 28, pitchers may begin a detailed throwing program with gradual return to competition.

References are listed here.

Now we will proceed with the surgical technique.

A standard medial approach to the elbow is utilized; flaps are raised. It is important to keep a close eye out for the medial antebrachial cutaneous nerve, which is typically distal to the medial epicondyle if it is present. Try to preserve that to avoid postoperative pain or neuromas. The flaps are raised and the ulnar nerve is identified, we typically do not move the ulnar nerve unless it is symptomatic preoperatively.

The flexor pronator fascia is split to end up proximally right at the anterior inferior medial epicondyle. There is a small raphe that is a pretty obvious place to split the fascia, and then a muscle splitting approach is utilized essentially just teasing the muscle off the deep layer underneath the muscle that is the medial UCL. Care is taken to carefully tease off this muscle deep but without entering the ligament at this point, and a small self-retaining retractor can be placed deep within the muscle; again, reflecting the last few fibers down in the area of the sublime tubercle to have a real good look. There is the sublime tubercle going all the way proximally to the anterior inferior medical epicondyle.

It is unusual for the ligament itself to be completely avulsed, although sometimes it is completely avulsed. But, it’s not uncommon at all to have ligament insufficiency without complete disruption. So the ligament is incised parallel with its fibers from the sublime tubercle to the anterior inferior medial epicondyle which shows the medial ulnohumeral joint. Then carefully the native medial UCL is very carefully subperiosteally dissected throughout its course. I use this at the end of the procedure to augment the reconstruction, so this is not excised, it is just incised, and elevated.

So here is the medial compartment. We have released now the flexor pronator fascia proximally to get to the medial column. It is important at this point to identify the ulnar nerve even it is not being transposed, to identify it. The proximal tunnels are at the medial column and a bit more anterior as well with a healthy bone bridge in between. And so once this has been identified, we use a 3.5-mm drill bit to drill the anterior inferior medial epicondyle a unicortical drill hole and then have a corresponding drill hole as the same from the medial column and anteriorly. These don’t directly join, but then I used curved curettes to clean out the bridge between the tunnels and also dilate the tunnels somewhat. These curved curettes are very helpful particularly for this anterior tunnel.

The humeral tunnels are completed, and we are now identifying the sublime tubercle. In this case, we use cortical fixation so a guide pin is initially started but then aimed distally and dorsally to avoid any involvement of the proximal radioulnar joint. The guide pin is initially placed, and this proximal cortex is drilled based on the size of the graft, in this case 5 mm, and then the opposite cortex is drilled to accept the cortical fixation, in this case 4 mm.

Once the tunnel on the ulnar side is created, the cortical suspensory fixation device is placed just outside of the cortex, it is not taken all the way through the forearm but just right outside the cortex, and the polyester sutures are pulled in a divergent force to secure the cortical fixation on the opposite cortex. And so that is ready to pass distally. We then use a Hewson suture passer (Smith+Nephew; Fort Worth, TX) to start the passage of the graft. Essentially, the graft is passed from proximal to distal, and then back proximally. And so the way this is done is this gracilis autograft is contoured on the back table; it is important for the edges to be bulleted or contoured and tapered to help facilitate passing. The graft is passed.

You will notice that I also utilize an additional suture where the closed end is distal to allow passage of the graft back proximally later in the case, and so this is the passage of the graft from proximal to distal through the anterior inferior medial epicondyle along with the additional suture for later. So we will do the same thing in the anterior tunnel. In this case, I use the Hewson suture passer from proximal to distal and adding another little suture loop is simply done to bring that proximally, and then that is used to bring the graft down, as well as an additional closed-loop suture, which will be used to pass the graft proximally later in the case. So there is the graft and there is a closed-loop suture that is taken through the anterior distal humeral tunnel and brought down.

I do think it is helpful to be a little meticulous at this point to make sure your sutures aren’t wound up with one another and just to concentrate a bit on the suture management at this point, which will help facilitate the graft passing coming back up.

So there is the closed end graft proximally with a very strong and healthy medial bone bridge, and the passing sutures are placed as well. The graft is then placed through the polyester loop of the cortical fixation in the sublime tubercle, and then those sutures are then simply brought down to bring down the graft. I also use a #5 suture tape that is placed in parallel with the graft as you can see it goes along with it; this is now brought down into the proximal ulna at the area of the sublime tubercle. The sutures are tensioned, and there is some slack placed in the graft itself to allow the graft to be brought into the tunnel with the cortical fixation device.

So that is the initial 2-ply portion of the graft that is reinforced by the cortical fixation on the ulna. Now we use the sutures that we previously placed to pass the graft back up proximally through the anterior inferior medial epicondyle, along with the #5 suture tape, which again is utilized to help provide additional internal fixation as well as load-sharing during the healing of the graft.

There is the proximal tunnel, the suture is tensioned, and the graft is tensioned. Again, if the edges of the graft are bulleted or tapered nicely it passes quite well through these tunnels. I do think it is important to have these additional sutures in place it just makes this a very simple process to slide the graft and the additional #5 suture back up proximally.

So here is the graft being passed proximally and make sure it is nicely tensioned. Often the graft ends are docked within the tunnels, and only the sutures are brought out the apertures for tying. Occasionally, as in this case, there are a few millimeters of graft that extend beyond the aperture, which is not a problem, as they are sutured very securely. I start with tying down the #5 suture tape. It is important for the elbow to be at about 30 or 40° of flexion and supination to close down the medial ulnohumeral joint. The suture tape is tied, and then the sutures from the graft itself are very securely tied over this healthy bone bridge proximally.

It is a very secure reconstruction. The graft is tensioned at several occasions. Here at the end I’ll give a little more tug of the polyester sutures, which is part of the cortical fixation at the sublime tubercle, and there is the reconstruction. As mentioned earlier, I then take a #2 suture and take the native medial UCL and reinforce the reconstruction by bringing this ligament together. I also incorporate the graft reconstruction itself. I personally think that this helps with the blood supply of the reconstruction but also helps tension the medial soft tissues as well. I’ll put 2 or 3 figure of 8 sutures through the graft and the native medial UCL and tie those down at the conclusion of the procedure. It is a real satisfying end to the procedure; it brings down the soft tissues, it is very anatomic. This is after again 2 or 3 figure of 8 sutures are placed to reinforce the reconstruction.

The new UCL is extremely robust and very thick. The elbow is taken through a full arc of motion, which is certainly possible given the anatomic location of the graft. I then take a vicryl suture to close the flexor pronator split distally, and it is also used to close the split of the flexor pronator proximally over the sutures from the graft and #5 suture tape. Those are buried, so there is no prominence of any sutures throughout the elbow.

This distal flexor fascia is simply closed in a locking fashion to conclude the procedure.

So again, this is the surgical technique for a very robust 4-ply medial UCL reconstruction which utilizes a gracilis autograft, a strong proximal bone bridge, cortical fixation at the sublime tubercle, and a #5 suture tape in parallel to augment fixation, as well as provide load sharing during the healing process.