Surgical technique
thromboembolic, knee flexion angle for 8, knee brace, knee flexion, hip flexion, bipolar
STERILE, DECUBITUS, MUSCLE RELAXATION
An intubation or spinal anaesthesia was used, and a preoperative single shot of antibiotics with Cefazolin 2 g was intravenously administered according to the hospital standards. The patient was positioned prone with 60° hip flexion and simultaneous 60° knee flexion. Special care was taken to carefully support the patient’s body by padded surgical cushions to prevent a build-up of decubitus. A sterile gaze was precisely taped to fully cover the rima ani. A self-adhesive, sterile drape was then glued around the ipsilateral gluteus and the posterior part of the proximal thigh, to allow sufficient surgical exposure. The lower leg was fully covered with sterile stockinet and taped shut. The entire surgical aperture was then covered with an antimicrobial Ioban foil (3 M™ Ioban™ Steri-Drape™, 3 M™, MN, USA). The skin incision was performed strictly in the gluteal sulcus. Under a constant haemostasis with bipolar forceps, the incision was deepened to the deep fascia, which was displayed and horizontally incised. The caudal border of musculus gluteus maximus was identified and moved proximally. Medially and caudally from it, the hamstring fascia was vertically incised. The exposure was held in place with Langenbeck retractors and medially as well as laterally around ischial tuberosity placed Hohmann retractors. The sciatic nerve was not specifically searched for but great care was taken not to damage or compress it when placing the retractors.The torn proximal hamstring tendons were identified, and a surgical debridement was performed. Subsequently, the hamstring origin on the ischial tuberosity was localized. We projected the modified reinsertion point 10 to 15 mm (depending on the patients’ anatomy) more lateral and proximal of the ischial tuberosity. This location was thoroughly debrided using a Luer forceps and three Arthrex BioComposite Corkscrews (FT 5.5 mm × 14.7 mm anchors, Arthrex, FA, USA) were introduced into the bone. Two of these were placed proximally and one distally. The non-resorbable FibreWire anchor-threads (FibreWire, Arthrex, FA, USA) were tightly sutured through the full thickness of the hamstring tendon using a Baseball-Stitch-Technique from proximal to distal. The armed tendon was then compressed using a Pulley-Method against the debrided bone and the anchors. After tying the surgical square knots, the remaining FibreWire was cut away (Fig. Intraoperative photographs. Postoperatively, the patients were allowed to partially bare weight (15 kg) and were constantly wearing a knee brace (Hinged Knee Brace, DonJoy, TX, USA) allowing knee extension up to 30° knee flexion angle for 8 weeks after the surgery. Hip flexion was not mechanically limited, but the patients were advised not to flex the hip more than 60° for 8 weeks after the surgery. First postoperative mobilisation took place under the control of a physiotherapist, and the patients were discharged when mobilisation and walking stairs with crutches was performed independently and safely. The supervised physiotherapy continued after hospital discharge. Initially, only procedures for muscle relaxation were allowed. After 4 weeks, isometric muscle strengthening and patellar mobilisation was introduced. Stretching of the hamstrings was prohibited for 4 months postoperatively. A daily use of thromboembolic prophylaxis with Deltaparin natrium (M.R. 4000–6000 D) (5000 UI s.c.) was prescribed for 8 weeks. Stitch removal was not necessary because of the use of a resorbable intradermal skin suture. Clinical follow-up was performed at 6 to 8 weeks postoperatively.