Objective: Reconstruction of the extensor mechanism of the knee joint by stable suture of the quadriceps tendon. Early functional treatment.
Indications: Acute or partial disruption of the quadriceps tendon close to the proximal patella pole with loss of extensor function of the knee joint.
Contraindications: Open rupture of the quadriceps tendon with extended soft-tissue damage and high risk of or ongoing inflammation until healing of the soft tissues. Chronic quadriceps tendon rupture. Ruptures at the musculotendinous junction.
Surgical technique: Supine positioning of the patient on a standard operating table with the knee in 30 degrees of flexion. Securing of the proximal tendon stump with two Bunnell sutures using no. 2 Fiber-Wire (Arthrex GmbH, Karlsfeld/Munich, Germany). Creation of a transverse, central trough in the superior pole of the patella. Transosseous refixation of the quadriceps tendon through longitudinal transpatellar drill holes. Intraoperative evaluation of the stability of the suture at 60 degrees of flexion. Repair of the retinacula with multiple interrupted sutures.
Postoperative management: Partial weight bearing (15-25 kg) for 6 weeks. Knee orthesis for 6 weeks, with increase of the initially allowed flexion of 30 degrees every 2 weeks by another 30 degrees . Initially, continuous passive motion (CPM) and passive movement exercises up to 60 degrees of flexion. After discharge from hospital, outpatient physical therapy with prone active flexion exercises. At the beginning of the 5th week, start with active and passive extension of the knee joint. From the 7th week on, full weight bearing is allowed and coordinative and strengthening exercises should be commenced. Sport activities can gradually be taken up after 3 months.
Results: Early diagnosis, timely surgical repair and early functional treatment are important for the outcome of quadriceps tendon ruptures. With the presented method, ruptures close to the upper patella pole can be treated. The majority of quadriceps tendon ruptures takes place in this area since the avascular zone found here predisposes to degenerative changes.