Endoscopic Repair of the Proximal Hamstring

Abstract

Background:

Proximal hamstring injuries are increasingly common. While open repair with suture anchors placed in the ischial tuberosity has long been the gold standard technique for surgical management, endoscopic techniques can allow for smaller incisions, reduced wound complications, and an expedited recovery.

Indications:

Patients with full-thickness 3-tendon proximal hamstring tears, 2-tendon tears with retraction >2 cm, or partial tears that remain symptomatic despite conservative management are considered for surgery. High-demand patients are often treated acutely, and low-demand patients may be offered surgery after a conservative management period.

Technique Description:

In the prone position, 2 arthroscopic portals are created in the gluteal fold. Fluoroscopy is used to verify safe portal placement, and the sciatic nerve is visualized along with the retracted tendon origin. The ischial tuberosity is identified, and the hamstring origin is debrided and decorticated. An accessory portal is created for suture anchor placement. Two double-loaded anchors are placed in the tuberosity, the sutures of which are used to repair the hamstring tendons using a horizontal mattress configuration. Patients undergo a stepwise postoperative physical therapy protocol.

Results:

An 85% return to sport rate can be expected following all hamstring repairs, with some studies reporting as high as 95% after endoscopic repair. Compared with nonoperative treatment, proximal hamstring repair overall results in higher patient satisfaction and return to sport. While large studies have yet to report on outcomes compared with the traditional open technique, the smaller incisions look to reduce wound complications and postoperative pain.

Discussion/Conclusion:

Recent advancements in endoscopic techniques have allowed for adequate visualization and robust repair of proximal hamstring avulsions. We present our endoscopic technique of the proximal hamstring, which, compared with the traditional open repair, can decrease perioperative complications and accelerate recovery.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

Here, we present our technique for endoscopic proximal hamstring repair. The authors’ disclosures are seen here.

Proper knowledge of the surgical anatomy of proximal hamstrings is vital, especially when indicating a patient for surgical intervention.

The proximal hamstrings originate at the ischial tuberosity and consist of 3 muscles: the semimembranosus, the semitendinosus, and the long head of biceps femoris, the latter 2 which comprise the conjoint tendon. In addition, as seen in the cartoon, the sciatic nerve runs directly lateral to the hamstring tendons, making it essential to identify and protect during any type of surgical intervention, either open or endoscopic.

Hamstring avulsion injuries typically occur as an eccentric loading of the hamstring muscles with the hip flexed while the knee is concomitantly extended. Most injuries have been found to occur during sports-type activities, with soccer, tennis, sprinting, skiing, running, water skiing, and martial arts representing a majority of the injuries. The most common patient demographic that these injuries occur in is women aged 49 to 59 years.

The patient presented after sustaining a work-related injury and suffering a pop in the right posterior thigh. Of note, the patient is approximately 12-month status after a similar traumatic event, which resulted in the need for a left proximal hamstring repair. The patient states that this pain feels similar to the prior injury.

On physical examination, the patient has a normal gait. His range of motion was preserved. He had tenderness to palpation about his ischial tuberosity. He did not have any ecchymosis present at the time of physical examination, and there were no positive, provocative hip maneuvers.

Here, we show a T2 coronal magnetic resonance imaging sequence revealing approximately 1.4 cm of retraction of his proximal hamstring tendon from its insertion on the ischial tuberosity.

Our indications for surgical intervention via the endoscopic repair technique are seen here. Generally, we indicate patients with small, partially retracted tears or partial thickness tears for endoscopic repair as more retracted tears are very difficult to mobilize and fix, in an arthroscopic manner.

Our surgical technique is presented here. The patient is placed in a prone position either on a normal operating room table with bumps or gel rows used to support the torso or on a Wilson frame which is placed on the middle of the table to allow the appropriate positioning. It is important to build a ramp of towels or pillows at the edge of the bed to maintain knee flexion and to relax the hamstring tendons during the procedure.

Two arthroscopic portals are made within the gluteal fold. We typically create the medial portal first, ensuring good trajectory to the ischial tuberosity and adequate space for the creation of the lateral-most portal. The lateral portal is created under direct visualization with care to come in at the lateral border of the ischial tuberosity to ensure safety with respect to the sciatic nerve, which is typically lateral to the hamstring tendons and can be dissected out during the course of the procedure.

Fluoroscopy can be used to verify correct portal placement and proximity to the ischial tuberosity prior to beginning the procedure and to maintain safe trajectories with vital neurovascular structures.

Here, we have identified the hamstring footprint on the ischial tuberosity and are using radiofrequency ablation to debride the footprint. Following debridement of the footprint, a burr is used to decorticate the issue tuberosity prior to anchor placement.

We once again introduce the shaver in via the lateral-most portal to ensure appropriate neurolysis of the sciatic nerve so that we may safely place anchors and pass them through the hamstring.

In this image, we see the sciatic nerve being retracted by an arthroscopic probe. This will allow us to keep it out of our way during suture management and repair of the hamstring.

For surgical fixation of the tear, an accessory portal is typically created between the medial and lateral portals and approximately 1 to 2 cm distal so that adequate trajectory can be obtained for fixation of the tendon.

Anchors are placed with care to stay orthogonal to the ischial tuberosity bone. The anchors are tapped and then placed.

Fluoroscopy can be used to confirm placement and trajectory of the anchors at the surgeon’s preference.

Our preferred construct uses 2 double-loaded anchors. Here, we see the penetrator coming through the torn hamstring tendon and retrieving the sutures for suture placement and the torn proximal hamstring. This is repeated in a horizontal mattress fashion for each pair of sutures seen here. This is then repeated for the other anchor.

We typically use rotator cuff repair–type instruments, including penetrators and suture passers. Hip arthroscopy instrumentation in the form of suture passers can also be used to safely puncture the tendon and retrieve these sutures for shuttling.

Suture pairs are then retrieved and the passed sutures are sequentially tied, reducing the proximal hamstring tendon to the ischial tuberosity.

Care is taken throughout the procedure to maintain the safety of the sciatic nerve with respect to the repair construct. The final image of the repaired hamstring tendon is seen here.

Postoperatively, the patient is made touch-down weightbearing for the first 2 weeks following surgery with progression of their weightbearing with their physical therapist. They are kept in a hinged knee brace locked in 45° at all times to prevent tension on the repair.

Phase 2 of the protocol consists of normalizing the patient’s gait and functional movements. Flexion is limited to less than 60°. We also focus on hip and core strengthening.

Phase 3 of the protocol includes beginning sport-specific and work-specific movements and getting strength back to approximately 75% of the contralateral side.

In phase 4, we continue strengthening beyond body weight exercise and begin to transition to full return to work and sport.

Patients are allowed to return to sport when it is deemed they may do so safely by the physical therapist and training surgeon and when they have dynamic muscular control of their lower extremity with multiplane activities at full exertion.

Patient-reported outcomes within the sports medicine literature following hamstring repair are good. A study by Willinger et al in 2020 reported an 85% return to sport rate with improvement in Harris Hip Score and visual analog scale (VAS) pain postoperatively compared with nonoperative treatment.

One study reported that proximal hamstring repair resulted in higher patient satisfaction as well as return to sport rates.

In addition, a study by Kurowicki et al found that endoscopic hamstring repair patients demonstrate a 95% return to sport rate with low postoperative VAS pain scores and high modified Harris Hip Scores.

Thank you for your interest in our technique.