**Reconstruction of Chronic Proximal Hamstring Tear: A Novel Surgical Technique with Semitendinosus Tendon Allograft Assisted with Autologous Plasma Rich in Growth Factors (PRGF)**

**Antonio Ríos Luna 1,\*, Homid Fahandezh-Saddi Díaz 2, Manuel Villanueva Martínez 3, Ángel Bueno Horcajadas 4, Roberto Prado 5, Eduardo Anitua <sup>5</sup> and Sabino Padilla <sup>5</sup>**


**Abstract:** The reconstruction of a chronic proximal hamstring tear is a challenging pathology that posits difficulties to surgeons due to the distal retraction of the hamstring tendon stumps and the entrapment of the sciatic nerve within the scar formed around the torn hamstring tendon. We describe a novel surgical technique using a semitendinosus tendon allograft sutured in a "V inversion" manner, thereby avoiding an excess of tension and length of the new reconstructed hamstring tendons. In addition, and in order to speed up the healing process and avoid new sciatic entrapment, we assisted the surgery with liquid plasma rich in growth factors (PRGF) injected intraosseously, intratendinously and within the suture areas, as well as wrapping the sciatic nerve with a PRGF membrane. In conclusion, this novel approach offers mechanical and biological advantages to tackle the large retraction of hamstring stumps and the entrapment of the sciatic nerve within the scar.

**Keywords:** proximal hamstring avulsion; allograft reconstruction; chronic; PRGF; platelet-rich plasma; PRP
