¹Medizinische Hochschule Hannover, Hannover, Deutschland

Text

Question: Chronic proximal hamstring avulsions are rare. They often involve scarring of the sciatic nerve, fatty muscle degeneration and increased level of tendon retraction. Primary repair is difficult which forces the surgeon to deploy some kind of allo- or autograft to augment the tendon. We present a case of a 60-year-old male patient with chronic avulsion injury to the hamstrings with a history after failed surgical repair one year prior to presentation in our outpatient clinic in 2021. MRI Imaging showed a tendon retraction of at least 10 cm. Clinical symptoms were weakness of the hip extension, as well as a globus feeling in his posterior thigh area and neurological symptoms with numbness along the sciatic nerve dermatomes.

Material and methods: A posterior approach to the thigh was performed. The proximal end of the hamstring tendons was identified and a tendon retraction of 13 cm was observed. The muscle showed a fatty degeneration. The sciatic nerve was circumferentially entrapped and surgically released. Hamstring reconstruction was performed by 1. reconstruction of the defect via a harvested ipsilateral semitendinosus graft, 2. the reinsertion into the ischial tuberosity through an intraosseous canal measuring 8.5 mm, and a further proximal fixation with a suture anchor (Arthrex- SwiveLock SP-Anker) and finally 3. a mesh augmentation was performed (Fm. Implantcast, Hamburg Germany)).

Results: At the one-year follow-up, the patient reported a complete recovery of the neurological sciatic nerve symptoms. Moreover, an 80% subjective improvement of mobility and strength in his lower extremity was reported. At the final 4-year follow-up the patient showed a regain of full strength of the hip extension and knee flexion compared to the other side with a Harris Hip score of 91 points.

Conclusions: Even though chronic avulsion injuries of the proximal hamstrings present as a major challenge to the patient and surgeon it is well worth performing it. In a case of a 60 years old patient, we demonstrate a new combination of established reconstruction techniques with excellent short and long-term results. It allows patients to regain strength, relief of neurological symptoms and increases the chance of return to activity and sports.