What is the recommended operative repair technique for a patient with a prior quadriceps tendon repair using bone tunnels who now has a patellar fracture and re‑rupture of the quadriceps tendon?

Surgical Management of Combined Patellar Fracture and Re-ruptured Quadriceps Tendon After Prior Bone Tunnel Repair

For this complex scenario involving both patellar fracture and quadriceps tendon re-rupture following prior bone tunnel repair, perform acute surgical repair addressing both injuries simultaneously: repair the quadriceps tendon using transpatellar bone tunnels (avoiding the previous tunnel sites if compromised), fix the patellar fracture with appropriate internal fixation, and strongly consider augmentation with cerclage wiring or local tendon reinforcement given the compromised tissue quality and high risk of re-failure.

Surgical Approach and Technique

Quadriceps Tendon Re-Repair

• Transpatellar bone tunnels remain the primary fixation method for quadriceps tendon ruptures at the patellar insertion, even in revision scenarios 1
• Plan new tunnel placement carefully to avoid weakening the patella further or intersecting with previous tunnel sites, as tunnel placement is a critical technical factor in preventing catastrophic failure 2
• The bone quality at the patella may be compromised from both the fracture and previous tunnels, requiring meticulous surgical planning 2

Patellar Fracture Management

• Fix the patellar fracture with appropriate internal fixation based on fracture pattern (tension band wiring, screws, or plates depending on configuration) 3
• Component loosening or loss of active extension of 20° or greater are clear indications for surgical treatment of patellar fracture 3
• Address the fracture fixation first or simultaneously with tendon repair to provide a stable platform for the quadriceps repair 4

Augmentation Strategy

• Strongly consider augmentation with cerclage wiring to protect the repair, particularly given the compromised tissue quality from prior surgery and current trauma 1, 5
• Local tendon augmentation using semitendinosus or gracilis autograft should be considered, especially if tissue quality is poor or there is soft-tissue loss 3, 4
• Augmentation is particularly important in this revision scenario where tissues are compromised and mechanical factors contributed to the initial failure 2

Critical Technical Considerations

Addressing Previous Bone Tunnel Sites

• The previous bone tunnels may have weakened the patella and contributed to the fracture pattern 2
• Avoid placing new tunnels through compromised bone or in locations that intersect with previous tunnels 2
• If the patella is severely compromised, consider alternative fixation methods or more extensive augmentation 3

Repair Tension and Positioning

• Fix the repair in full extension to prevent severe extensor lag, as grafts and repairs stretch over time 3
• Ensure accurate reapproximation of ruptured tendon ends and repair torn extensor retinacula 5
• Mechanical factors, including proper tension and alignment, are essential to prevent recurrence 2

Timing of Surgery

• Acute repair is strongly preferred and should be performed as soon as medically feasible 1, 5
• Outcomes are excellent if repair is done acutely, with significantly poorer outcomes associated with delayed repair 1
• The prognosis depends largely on the interval between injury and repair 5

Postoperative Rehabilitation Protocol

• Allow immediate weight-bearing with the knee locked in extension using a hinged brace and crutch support 1
• Start limited arc motion early with active flexion and passive extension, then advance progressively 1
• Follow a structured rehabilitation program with comprehensive patient education, as compliance-related factors significantly contributed to this type of sequential failure 2
• Advance to full active range of motion and strengthening only after adequate healing 1

Critical Pitfalls to Avoid

• Patient compliance is absolutely critical—noncompliance with protective devices and falls during early recovery are documented causes of catastrophic failure 2
• Inadequate tunnel planning can lead to patellar weakening and subsequent failure 2
• Delayed repair significantly compromises outcomes, risking loss of full knee flexion and decreased quadriceps strength 5
• Insufficient augmentation in this high-risk revision scenario increases rerupture risk 1, 3
• Failure to address both the fracture and tendon injury adequately will result in extensor mechanism dysfunction 4

Expected Outcomes

• With acute repair and proper technique, excellent functional recovery is achievable even in this complex revision scenario 2
• Complications include quadriceps atrophy, knee stiffness, and rerupture, but are minimized with acute intervention 1
• Structured follow-up is essential to optimize healing and prevent recurrence 2