Endoscopic Proximal Hamstring Repair Using a Modified Whipstitch: A Technical Note

Abstract

Background:

Tearing of the proximal hamstring tendon is a common injury in athletes for which surgical repair is being increasingly utilized. The described techniques for endoscopic repair employ a simple or mattress suture configuration. We hypothesize that the incorporation of a running modified whipstitch may allow for increased suture purchase and sturdier tendon fixation.

Indications:

Patients with partial tears, 2-tendon tears and >2 cm retraction, or 3-tendon tears refractory to conservative management are typically indicated for surgery.

Technique Description:

In the prone position, 2 portals are established in the gluteal crease. Neurologic structures such as the posterior femoral cutaneous nerve and the sciatic nerve are visualized. The ischium is decorticated, and a triple-loaded suture anchor is placed in the ischial tuberosity. Using a tissue penetrator and a suture-passing device, a modified whipstitch suture configuration is constructed to secure the torn tendons.

Results:

Overall, following endoscopic surgical repair, most patients demonstrate improvement in functional outcomes metrics and achievement of patient acceptable symptom state in >70% of cases. Return-to-sport rate between 77.3% and 95% has been described in the literature.

Discussion/Conclusion:

Open repair utilizes a running suture configuration, whereas endoscopic repair has traditionally been performed with simple or mattress constructs. A modified whipstitch, performed endoscopically, may provide the durability of open repair with decreased rates of perioperative complications associated with endoscopic repair. Further work comparing suture techniques and postoperative outcomes should be investigated.

Patient Consent Disclosure Statement:

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

We present our technique for endoscopic proximal hamstring repair using a modified whipstitch. Here are our disclosures.

Background

Proximal hamstring tears are a relatively common injury in athletes that result in pain, weakness, and muscular atrophy. These can occur via 2 mechanisms, either acute due to a high force with the hip in flexion and the knee in extension or attritional due to repetitive stresses. Surgical indications include 2 tendon injuries with greater than 2 cm of retraction or 3 tendon injuries.^1,3,4,7,9

Both endoscopic and open surgical techniques have been described, each with their own advantages and disadvantages. Endoscopic repair is favorable in partial avulsions with minimal retraction. Open repair is more favorable in complete tears that are retracted. The benefits of endoscopic repair include smaller surgical incisions that are associated with decreased wound complications, bleeding, and infection. Tendon tear and nerve structures can also be directly visualized with the endoscopic technique. Disadvantages of endoscopic repair include a greater degree of difficulty dealing with more retracted tears.

Our patient is a 44-year-old female ultra-marathon runner. She had been training for a race 6 months ago and started developing buttock and posterior thigh pain. Her physical examination was notable for tenderness over the ischium and pain with resisted knee flexion. The pain persisted despite activity modification and several months of physical therapy.

Seen here are anatomic dissections detailing the pertinent anatomy to a proximal hamstring repair. On the far left image, labeled “1,” is the gluteus maximus muscle, and labeled “2” is the proximal hamstrings. The middle image, number “3,” details the proximal hamstring insertion; number “4” details the sciatic nerve; and “5” indicates the posterior femoral cutaneous nerve.

The left image is an axial T2 sequence from hip magnetic resonance imaging demonstrating a high-grade partial-thickness tear of the conjoined tendon as it inserts on the ischium, noted by the yellow arrow. The right image is a T2 coronal image demonstrating the same tear.

Technique Description

Given that our patient had failed several months of conservative measures and still had unacceptable pain and dysfunction, we indicated her for an endoscopic proximal hamstring repair. Our preferred position is prone with the chest on well-padded bolsters and the foot resting on a padded mayo stand held in about 45° of flexion. The right image details our preferred portal placement. The medial portal is placed first; this is located in the gluteal fold—just lateral to the medial border of the ischium. The lateral portal is then made under direct visualization as it is near the sciatic nerve.

Viewing from the medial portal, a lateral portal is made under direct visualization, and a shaver is introduced through the lateral portal to help with blunt dissection to define the sciatic nerve, as seen here. The viewing portal is then switched to laterally and the shaver introduced through the medial portal to help identify the tear, seen here in the rent between the conjoint tendon and the semimembranosus. You can palpate this to feel the rent with the shaver. We take down these adhesive fibers, and as you can see here, the conjoint tendon has pulled off the ischium. Gentle debridement is performed.

Viewing with the 70° scope through the lateral portal and working through the medial portal, an electrocautery device is introduced to help with preparation of the ischial tuberosity for reattachment of the tendon. After the cautery is used, a burr is used to gently decorticate the ischium. Then a single triple-loaded PEEK anchor is punched, and a tap is introduced.

Again, viewing through the lateral portal with a 70° scope and working through the medial portal, we first introduce a switching stick to use as a probe to feel the extent of our tendon tear. Then we introduce the shaver to make sure we can fully define the tendon before we start passing our sutures and do a good bursectomy. This is now looking more laterally but still working through the medial portal again, defining our tendon in its entirety, making sure we are always cognizant of the nerve lying more lateral.

Viewing through the lateral portal and working through a cannula that has been placed in the medial portal, we then begin to pass our sutures. We start by using a penetrator, going through the tendon, and we grab the dark-colored suture. Then we use a self-capturing suture device as seen here to do a running whipstitch configuration, distal to proximal, up the tendon. We try to get 3 to 4 throws with a single limb. The penetrator is then used to grab the other limb, which will serve as the post. We then repeat the process with the other colored sutures, again trying to obtain 3 to 4 running whipstitch throws through the tendon, trying to space these out to not capture the other sutures. Suture management can be challenging; our preference is to actually remove the cannula after we pass each set of sutures, color the post-limb with the marking pen so it can easily be identified, and snap the suture pairs together outside of the cannula so they are discrete. We then grab them through the cannula, and we are ready to tie. An arthroscopic knot pusher is utilized to tie arthroscopic knots; we prefer half-hitches with alternating posts. You can see here that the nerve is intact and has been protected throughout the case. It can be helpful to utilize a switching stick through the accessory portal for gentle retraction of the sciatic nerve if the nerve is relatively close to the tendon. This completes out anatomic repair.

Pearls and key steps of this procedure include identifying important structures such as the posterior femoral cutaneous nerve, the sciatic nerve, and the tendon tear site. This can be challenging to do at times. We prefer to utilize our shaver as a probe to do blunt dissection and also as a shaver to debride bursal tissue. Second, removing adhesions is critical to help mobilize your tendon as well as for visualization. The ischial base and the anchor should be prepared in the usual fashion, with suture limbs passed through the tendon stump. We prefer to use a self-passing suture capturing device, which makes the whipstitch relatively easy to do. A secure tendon needs to be tied down to the ischial tuberosity through arthroscopic knots, with the sciatic nerve reevaluated after you have finished tying to ensure there has been no damage or suture running near it.

Our postoperative rehabilitation protocol is noted here. The patient is placed in a hinge knee brace locked in 15° of extension immediately after surgery. The initial phase of therapy is geared toward protecting the tendons. We do not allow for any hip flexion or knee extension during the time. The physical therapy begins after 4 weeks. Phase 2 is 7 to 12 weeks, and the goal of this is to normalize gait by gradually weaning the patient off of crutches and allowing for weightbearing as tolerated over this time frame. Weeks 13 to 16 focus on advancing strength and light sports-specific movements. Weeks 17 through 24 have a goal of returning to work and sport by working with physical therapy on more advanced movements, strengthening, and more explosive-type movements.

Discussion

Several clinical studies have reported outcomes after open and endoscopic repair of proximal hamstring tendon tears. The first study listed from OJSM details 35 repairs, 23 of which were open and 12 endoscopic at a minimum 5-year follow-up. ⁶ The endoscopic repair group demonstrated significant improvement in patient-reported outcomes that were equivalent to open repair. Study 2, from AJSM, reported on 75 repairs with varying grades and degrees of retraction. ⁵ Twenty-four tears were grade 2 tears with 2 or more tendons with less than 2 cm of retraction. For grade 2 tears, endoscopic repair resulted in greater than 70% achievement of Patient Acceptable Symptom State (PASS) at a minimum 2-year follow-up.

Several authors have reported return-to-sport rates after proximal hamstring repair. The first study, listed from Kurowicki et al., ¹⁰ details 20 endoscopic repairs for tears of 2 or more tendons with 2 or more cm of retraction, demonstrating a 95% return-to-sport rate at a minimum 1-year follow-up. The second study, listed from Fletcher and colleagues, ⁸ reported on 30 endoscopic repairs for partial-thickness tears or tears with 2 to 5 cm of retraction and demonstrated a 77.3% return-to-sport rate at a minimum 2-year follow-up. The final study from Alvero et al. ² reported on 20 endoscopic repairs of partial-thickness, attritional tears with over 6 months of symptoms, demonstrating an 80.0% overall return to running rate.

These are our references.

Thank you for taking the time to watch our video.