Patellar and quadriceps tendon repair restores the disrupted extensor mechanism of the knee following tendon rupture. The procedure addresses the time-sensitive injury of complete extensor tendon rupture, where active knee extension is lost and surgical repair is required to restore function. Acute repair within a few weeks of injury produces the most reliable outcomes.
What Is Patellar and Quadriceps Tendon Repair?
The extensor mechanism of the knee consists of the quadriceps tendon (above the patella), the patella, and the patellar tendon (below the patella). All three components must be intact for the knee to actively extend against gravity. Rupture of either tendon produces functional loss equivalent to a patella fracture: inability to lift a straight leg or actively extend the knee.
Repair principles are similar for both tendons:
- Quadriceps tendon repair: reattaches the torn quadriceps tendon to the superior pole of the patella using suture anchors or bone tunnels. Most commonly performed in patients over 40, often in tendons with pre-existing tendinosis.
- Patellar tendon repair: reattaches the torn patellar tendon to the inferior pole of the patella using similar fixation. More commonly performed in younger patients (under 40), often associated with pre-existing tendinosis.
Acute repair (within 4 weeks of injury) is technically simpler and produces better outcomes than chronic repair. Chronic ruptures with significant retraction may require tendon advancement techniques or graft augmentation.
Who Is a Candidate?
Candidates for tendon repair typically have:
- Complete tendon rupture documented on MRI or by physical examination
- Loss of active knee extension or significant extensor lag
- Active patient with functional and cosmetic concerns
- A medical profile that allows safe surgery
Partial tears with preserved active extension are typically treated non-surgically with bracing and rehabilitation. Chronic tears in patients with low functional demands may also be managed without surgery.
How the Procedure Is Performed
The procedure is performed through a vertical incision over the front of the knee centered on the rupture site. The torn tendon is identified and freed of any scar tissue. The patellar attachment site (superior pole for quadriceps, inferior pole for patellar tendon) is prepared.
The tendon is reattached using:
- Suture anchors placed in the bone with sutures passed through the tendon
- Bone tunnels drilled through the patella with sutures passed through both the tunnels and the tendon
- A combination of both techniques, with augmentation sutures protecting the repair during early motion
The retinaculum (the soft-tissue envelope around the tendon) is repaired. Active extension is tested before closing.
For chronic ruptures with retraction and tissue degeneration, tendon graft augmentation (using hamstring autograft or Achilles allograft) may be needed to bridge the gap.
Recovery and Rehabilitation
Recovery follows a protected protocol:
- Brace immobilization in extension for four to six weeks
- Passive range of motion within safe limits beginning early to prevent stiffness
- Progressive active extension from four to six weeks
- Strengthening from three months
- Return to most activities at three to four months
- Return to sport at six to nine months for patellar tendon, slightly faster for quadriceps tendon
Risks and Outcomes
Risks include re-rupture, persistent extensor lag, stiffness, hardware irritation, and infection. Outcomes after acute repair are good, with most patients regaining active knee extension and functional strength. Chronic repairs have more variable outcomes.
Why Dr. Chudik for Patellar and Quadriceps Tendon Repair
Dr. Chudik treats the full spectrum of extensor mechanism injuries, including time-sensitive acute tendon ruptures and chronic ruptures requiring tendon graft. His high case volume of knee surgery, particularly tendon repair across the upper and lower extremities, supports precise fixation construct selection and sequencing in cases combined with other knee pathology.