Title : Surgical repair of proximal hamstring tendon ruptures in middle aged non-athletic patients: A case series
Abstract:
Objective: Proximal Hamstring injuries occur due to eccentric contraction of the Hamstring group of muscles. It can be a Hamstring strain or partial or complete rupture of proximal hamstring origin. The Objective of this paper is to showcase our experience in surgical repair of proximal hamstring tendon ruptures with good clinical outcomes
Introduction:
Proximal hamstring tears are among the most common sports-related injuries and are frequently seen during eccentric muscle contractions, forced hip hyperflexion, and ipsilateral knee extension and fall accidents(1).
Anatomy
The hamstring muscle group consists of 3 posterior thigh muscles, including the semimembranosus, semitendinosus, and the biceps femurs muscles. The Biceps femoris laterally and semitendinosus medially together merge to form the conjoint tendon. The semimembranosus originates anterolaterally to the footprint of the conjoint tendon from the ischial tuberosity(2,,3rd ref of G.moatshe)
Classification
There are certain classification systems for hamstring injuries. Hamstring injuries were initially classified according to their clinical presentation ranging from grade 1 to grade 3. This classification system includes grade 1 (mild): overstretching but minimal loss of the structural integrity of the muscle-tendon unit; grade 2 (moderate): partial tear; and grade 3 (severe): total rupture.4 Wood et al.5 described a system of classification which was based on anatomic location of injury, degree of tear (partial or complete), degree of muscle retraction, and involvement of the sciatic nerve (sciatic nerve tethering). Type 1 injuries are osseous avulsions, type 2 are tears at the musculotendinous junction, type 3 are incomplete tendon avulsions, type 4 are complete tendon avulsions with no or minimal retraction, and type 5 are complete tendon avulsions with retraction of the tendon ends. Type 5 may be associated with sciatic nerve tethering (type 5b).5
Mechanism of injury
Proximal hamstring rupture from ischial tuberosity involves sudden hip flexion/knee extension causing hamstring contraction. There is eccentric contraction of the muscle with forced hip flexion with knee in extension.
Presentation
This condition presents with posterior thigh pain distal to the ischial tuberosity and significant ecchymosis as a result of haematoma from the tendon rupture and difficulty in sitting. The gait pattern is one of a stiff legged gait as a result of avoidance of hip and knee flexion.
Examination
There is tenderness over the injury site and bruising but palpation of the defect is difficult. It is important to test the peroneal branch of the sciatic nerve function because if there is an injury to this branch, this will cause weakness of the short head of the biceps femoris and may slow potential postoperative rehabilitation. Specifically, if there has been a neuropractic injury to the nerve, this may present as a foot drop or more subtly an eversion weakness of the ankle.
Investigations and Treatment
MRI is the gold standard investigation to confirm a hamstring tendon tear or avulsion from the ischial tuberosity origin. ?
The treatment of proximal hamstring injuries is based on early intervention rather than delayed intervention. In this paper, we are describing when operative treatment is justified and when the patient can be managed conservatively. We also are describing, incase surgical management is decided for the patient, the preferred approach for surgical repair of hamstring tendon tear and avulsion from the ischial tuberosity and a description of the rehabilitation protocol following surgery.
Methods
Our study group consisted of 4 patients. 3 of those patients, slipped and fell and felt a pull of the muscles on the back of the thigh. 1 patient felt a pop at the back of the thigh while playing football. All patients presented with weakness of the injured leg, especially knee flexion and hip extension. Bruising was seen on the back of the thigh in 2 of the 4 patients and a palpable gap below the ischial tuberosity was felt in only 1 patient. All patients had weak knee flexion and hip extension and it was painful.
MRI scans confirmed complete avulsion of hamstring tendons from the ischial tuberosity with a tendon retraction of at least 1.5 cos in 3 patients. In one patient, the MRI scan showed intra-substance muscle tear of the biceps femoris. Based on these results, patient with intra-substance tear was managed non-operatively with physiotherapy and rehabilitation and the other 3 patients with complete avulsion of hamstring tendons were managed surgically with acute repair within 4 weeks of the injury.
Surgical Procedure
The patient is placed in prone position and a 10 cm transverse subgluteal fold incision is taken centred over the ischial tuberosity. Gluteus Maximus fibres were identified and elevated. Sciatic nerve identified and protected throughout the procedure.Hamstring common tendon was found ruptured with evidence of tendinopathy. The ischial tuberosity was visualised with soft tissue dissection and the tendon footprint identified. Ischial tuberosity was freshened. Two Twinfix Ti 3.5 Suture anchors were placed in the ischial tuberosity on the tendon footprints. 2 Osteoraptor 2.9 sutures can also be used instead of Twinfix. The sutures were placed through the tendons and the tendons sutured back to the footprint. Common tendon insertion repaired enmass. Ischial tuberosity was covered with tendons. Integrity of repair was checked with Hip extension. Repair secure and stable with knee extension on table. Thorough washout of wound with normal saline done. Closure done with vicryl 0 and subcuticular with vicryl 2-0 and skin with Monocryl 3-0. Inadine and hydrofilm dressing applied.
Post-operative plan
Patient was advised full weight bearing with elbow crutches, no long stride walking. It was advised to keep hip and knee in flexion to avoid tension go hamstring repair and patient should not do long leg sitting. A hinge knee brace was given locked in 30-70 degrees. All patients were asked to follow up in 6 weeks, 3,6 and 12 months post op. Non-operative treatment and Post surgical repair hamstring physiotherapy and rehabilitation
Results
All 3 patients operated with surgical repair showed excellent results. On 6 weeks follow up, the surgical site was completely healed without any complications. Patients started full weight bearing at 6 weeks along with with continuing physiotherapy for graded hamstring muscle strengthening. 1 patient which was managed non-operatively and physiotherapy initially recovered well but then had a stumble down a flight of stairs which delayed his recovery but at the end of 1 year, he regained 85% of his muscle strength with physiotherapy and rehabilitation. The other 3 surgically treated patients recovered brilliantly and regained 95 % of the original muscle strength at the end of 1 year. They could do single leg dip with good control and cycling and all returned back to full activities within 6 months of injury
Discussion
Proximal hamstring tears occur mostly due to eccentric muscle contractions, forced hip hyperflexion, and ipsilateral knee extension and fall accidents. The patients present with complains of a sudden pain and popping sensation in the posterior thigh with bruising. Palpable gap is not always present but there is ipsilateral weak knee flexion. Surgical repair is preferred for complete avulsion and should be done within 4 weeks of injury because it allows easier re-approximation of the tendons to its insertion on the ischial tuberosity. Chronic repairs lead to difficulties which are encountered during the surgical procedure in view of excessive scarring and might also require sciatic nerve neurolysis and overall give a less favourable functional outcome over time as compared to acute repairs.
Review of Literature
Brucker and Imhoff described the functional assessment (by performing Cybex dynamometer isokinetic testing measuring maximum hamstring and quadriceps torque and peak torque ratio of hamstring to quadriceps at a velocity of 60 degrees per second) after repair of acute and chronic hamstring repairs in 8 patients.[5] MRI was used to confirm the diagnosis in all cases. Return to sports activities was allowed after 6-8 months. At 20 months follow-up, 50% complained of incisional pain and discomfort with one patient requiring an additional surgery after pullout of a metal suture anchor
Orava and Kujala treated 8 patients with surgical repair who had complete rupture (all 3 tendons) of the hamstrings from the ischial tuberosity.[7] The mean age of their patients was 40 years and the injury was the result of a sudden forceful flexion of the hip when the knee was extended, and occurred during athletics. The results with regard to function and strength were improved in the 5 patients who underwent repair less than 2 months following the injury compared to the 3 chronic repairs. In addition, the authors recommend nonoperative treatment for isolated biceps femoris ruptures as little functional disability results from this injury. Consequently, they recommended prompt surgery to accomplish a primary repair of the tendons to its origin.
Conclusion
Proximal tendon ruptures are rare but causes debility and affects the individual's day to day activities and has serious implications in a sportsperson for his future sports activities. MRI is the gold standard investigation in diagnosing hamstring tendon avulsions and should always accompany clinical suspicion. Complete avulsion should be managed surgically followed by proper hamstring rehabilitation and intra-substance tears or muscle strains can be managed non-operatively with physiotherapy. Surgical repair allows early rehabilitation and a good functional outcome in these patients and avoids the potential problem of gluteal pain due to chronic sciatic nerve compression.
