Tibial Tubercle Osteotomy: Patellar Tendon Realignment, Procedure, and Recovery

What is the surgery to move the patellar tendon?

The surgical procedure to move the patellar tendon is primarily known as a Tibial Tubercle Osteotomy (TTO), a procedure designed to realign the attachment point of the patellar tendon on the tibia to improve patellar tracking and stability within the trochlear groove of the femur.

Introduction to Patellar Tendon Realignment Surgery

The knee joint, a marvel of biomechanical engineering, relies on precise alignment and stability for optimal function. When this delicate balance is disrupted, particularly involving the patella (kneecap), it can lead to pain, instability, and functional limitations. Surgery to "move the patellar tendon" specifically refers to procedures aimed at repositioning the tibial tubercle, the bony prominence on the shinbone (tibia) where the patellar tendon inserts. This realignment is crucial for correcting issues like patellar instability and maltracking.

Anatomical Context: The Patellar Tendon and Its Role

To understand the surgery, it's essential to grasp the anatomy. The patellar tendon, sometimes referred to as the patellar ligament, is a strong, fibrous band connecting the patella to the tibial tubercle. It is an extension of the quadriceps tendon, which encases the patella. This entire unit—quadriceps muscle, quadriceps tendon, patella, and patellar tendon—forms the extensor mechanism of the knee. Its primary function is to transmit the powerful force generated by the quadriceps muscles to the tibia, enabling knee extension (straightening the leg). Proper alignment ensures the patella glides smoothly within the trochlear groove (a shallow V-shaped groove at the end of the femur) during knee movement.

Indications for Patellar Tendon Realignment Surgery

Patellar tendon realignment surgery is typically considered when conservative treatments (such as physical therapy, bracing, and activity modification) have failed to alleviate symptoms caused by patellar instability or maltracking. Key indications include:

• Recurrent Patellar Dislocations: The patella repeatedly slips out of its normal position, usually to the outside (lateral side).
• Chronic Patellar Subluxation: The patella partially slips out of alignment, causing pain and a sensation of instability.
• Patellofemoral Pain Syndrome (PFPS) with Maltracking: Persistent pain around or behind the kneecap due to abnormal patellar movement, especially when combined with a high Q-angle (a measure of quadriceps pull on the patella) or other anatomical predispositions.
• Patella Alta: A condition where the patella sits too high in the trochlear groove, predisposing it to instability. A TTO can lower the patella.
• Tibial Tubercle-Trochlear Groove (TT-TG) Distance: An increased TT-TG distance indicates a lateralized tibial tubercle, pulling the patella outwards and contributing to maltracking.

Understanding Patellar Tendon Realignment Surgery

The primary surgical procedure for moving the patellar tendon's attachment is the Tibial Tubercle Osteotomy (TTO). This procedure involves cutting a segment of bone from the tibia where the patellar tendon attaches and repositioning it.

• Medialization: Moving the tibial tubercle medially (towards the midline of the body) to reduce the lateral pull on the patella, improving its tracking within the trochlear groove.
• Distalization: Moving the tibial tubercle distally (further down the leg) to lower the patella in cases of patella alta.
• Anteriorization: Moving the tibial tubercle anteriorly (forward) to relieve pressure on the patellofemoral joint cartilage, sometimes used in cases of severe cartilage damage or osteoarthritis, though less common as a sole TTO goal.

Often, a TTO is performed in conjunction with other procedures to enhance patellar stability, most commonly a Medial Patellofemoral Ligament (MPFL) Reconstruction. The MPFL is a crucial ligament that prevents the patella from dislocating laterally. If it's torn or stretched due to dislocations, reconstructing it provides additional medial support.

The Surgical Procedure: What to Expect

A Tibial Tubercle Osteotomy is typically performed under general or regional anesthesia. The general steps involve:

1. Incision: An incision is made on the front of the shin, typically below the kneecap.
2. Bone Cut: Using specialized surgical saws, a precisely measured block of bone containing the tibial tubercle is carefully cut from the tibia.
3. Repositioning: The bone block is then moved to its new, corrected position. This might involve medialization, distalization, or a combination, determined by the specific anatomical abnormalities identified pre-operatively.
4. Fixation: Once in the optimal position, the bone block is secured to the tibia using screws. These screws typically remain in place permanently unless they cause irritation.
5. Ancillary Procedures (if needed): If an MPFL reconstruction is also performed, a new ligament (often using a hamstring tendon graft) is attached from the medial side of the patella to the femur.
6. Closure: The incision is closed with sutures or staples.

Post-Operative Recovery and Rehabilitation

Recovery from a TTO is a significant commitment, typically involving several months of structured rehabilitation.

• Immediate Post-Op (Weeks 0-2):
  • Pain management with medication.
  • Immobilization with a brace, often locked in extension or with limited range of motion.
  • Weight-bearing restrictions (non-weight bearing or partial weight-bearing with crutches).
  • Emphasis on swelling control (RICE protocol) and gentle, passive range of motion exercises as permitted by the surgeon.
• Early Rehabilitation (Weeks 2-6):
  • Gradual increase in knee flexion range of motion.
  • Initiation of gentle isometric quadriceps contractions and gluteal strengthening.
  • Progression of weight-bearing as bone healing progresses.
• Mid-Stage Rehabilitation (Weeks 6-12):
  • Focus on restoring full, pain-free range of motion.
  • Progressive strengthening of the quadriceps, hamstrings, glutes, and core.
  • Introduction of closed-chain exercises (e.g., mini-squats, leg presses).
  • Balance and proprioception training.
• Late-Stage Rehabilitation and Return to Activity (Months 3-6+):
  • Advanced strengthening and plyometric exercises.
  • Sport-specific drills and agility training.
  • Gradual return to full activity, typically not before 6 months, and sometimes longer for high-impact sports.

Full bone healing can take 6-12 weeks, but complete recovery and return to full function take considerably longer, often up to a year or more, depending on the individual and the complexity of the surgery.

Potential Risks and Complications

As with any surgical procedure, a Tibial Tubercle Osteotomy carries potential risks, including:

• Infection: Risk of infection at the surgical site.
• Bleeding/Hematoma: Accumulation of blood under the skin.
• Nerve Damage: Injury to nerves around the knee, potentially causing numbness or weakness.
• Non-union or Malunion: The bone block may not heal properly or may heal in an incorrect position.
• Hardware Irritation: The screws used for fixation can sometimes cause pain or irritation, potentially requiring removal in a secondary procedure.
• Persistent Pain or Stiffness: Despite successful surgery, some individuals may experience ongoing pain or limited range of motion.
• Re-dislocation/Re-injury: While less common after successful TTO, there is still a small risk of recurrent instability.
• Compartment Syndrome: A rare but serious condition involving increased pressure in muscle compartments.

Expected Outcomes and Long-Term Considerations

The success rate for Tibial Tubercle Osteotomy in addressing patellar instability is generally high, with many patients experiencing significant improvement in stability, reduced pain, and improved function. Long-term outcomes depend on various factors, including the initial diagnosis, surgical technique, adherence to rehabilitation, and the presence of pre-existing cartilage damage. While the surgery aims to restore normal knee mechanics, diligent rehabilitation is paramount for achieving optimal results and minimizing the risk of re-injury. Patients should maintain a regular exercise routine to support the long-term health of their knee.

Conclusion

Tibial Tubercle Osteotomy is a precise surgical intervention designed to correct the alignment of the patellar tendon's attachment point on the tibia. It is a critical procedure for individuals suffering from chronic patellar instability and maltracking that has not responded to conservative management. Understanding the anatomical basis, surgical process, and the demanding but crucial rehabilitation phase is essential for anyone considering or undergoing this specialized knee surgery.