Early TKR Failure-Common Mistake

Courtesy: Dr C Ranawat, Ashok Shyam TV, Ortho

Foundational Premise

• We can always improve surgical outcomes.

• Most complications occur because of preventable errors.

• Understanding common technical mistakes helps reduce failures.

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Common Causes of Surgical Errors

1. Poor Exposure

• Limited visualization leads to “guesswork.”

• Small-incision approaches may:

  • Compromise rotational alignment.

  • Leave retained cement (especially posterolateral corner).

• Inadequate exposure ? Technical inaccuracies.

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2. Improper Soft Tissue Balance

Often triggered by incorrect bone cuts:

• Example:

  • Tibial cut less than intended (e.g., 7 mm instead of 10 mm).

  • Leads to:

    • Excess posterior femoral resection.

    • Increased distal femoral resection.

    • Elevated joint line.

• One technical error creates a chain reaction.

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3. Component Sizing Errors

• Undersizing or oversizing femoral component.

• Rotational malalignment.

• Poor patellofemoral tracking.

• Increased anterior knee pain.

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4. Poor Cement Technique

• Inadequate bone–cement interface.

• Leads to early loosening.

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5. Soft Tissue Trauma and Closure Issues

• Excessive pulling and retraction.

• Tight closure ? Postoperative pain.

• Delayed wound healing.

• 10% of delayed wound healing may progress to infection.

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Consequences of Technical Errors

• Infection.

• Hematoma (e.g., inferior lateral genicular vessel injury).

• Arthrofibrosis.

• Anterior knee pain.

• Patellofemoral complications.

• Malalignment.

• Instability.

• Poor fixation.

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Common Causes of TKA Failure (Published Data)

Most frequent reasons for revision:

1. Instability

2. Polyethylene wear

3. Infection

4. Loosening

5. Patellofemoral complications

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Personal Revision Experience

Most common reasons:

• Infection

• Instability

• Implant failure (wear/breakage)

• Osteolysis

• Loss of fixation

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Goals of Surgery

• Minimize soft tissue trauma.

• Optimize alignment in all three planes.

• Achieve balanced flexion and extension gaps.

• Preserve joint line.

• Ensure proper sizing and fixation.

• Provide effective pain control to promote early function.

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Soft Tissue Preservation Strategy

• Avoid tourniquet use (reduces soft tissue damage).

• Avoid quadriceps cutting.

• Use gentle retraction.

• Preserve suprapatellar pouch.

• Prefer spinal/epidural anesthesia.

• Maintain controlled blood pressure.

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Perioperative Optimization

• Preoperative patient education.

• Multidisciplinary team approach.

• Aggressive pain control.

• Early mobilization.

• Avoid flexion contracture.

• Gradual strengthening and stair training.

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Key Technical Principles

Alignment

• Maintain mechanical alignment in all planes.

• Ensure tibial cut is accurate:

  • Alignment rod should pass through center.

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Femoral Canal Entry

• Precise entry point critical.

• Should align with mechanical axis.

• Errors here affect:

  • Extension gap.

  • Overall alignment.

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Flexion and Extension Gaps

• Rectangular and symmetric.

• Posterior femoral cut parallel to tibial cut.

• Restore femoral offset.

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Component Positioning

• Correct femoral sizing.

• Lateralize femur appropriately.

• Proper tibial rotation.

• Avoid overstuffing patellofemoral joint.

If properly positioned:

• Patella tracks without release.

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Patellofemoral Considerations

• Avoid internal rotation of components.

• Proper lateralization reduces need for release.

• Balance flexion gap carefully.

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Cement Technique

• Warm cement for optimal handling.

• Apply to both implant and bone.

• Pressurize adequately.

• Aim for uniform cement mantle (AP and lateral views).

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Wound Closure

• Careful dermal closure.

• Avoid tension.

• Prevent ugly scar and wound complications.

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Infection Prevention

• Prophylactic antibiotics.

• Proper draping.

• Limit operating room traffic.

• Consider laminar airflow.

• Minimize surgical time.

• Meticulous closure.

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Radiographic Goals

A well-performed TKA should show:

• 90° tibial cut.

• Proper femoral lateralization.

• Uniform cement mantle.

• Appropriate posterior tibial slope.

• Alignment rod extension should intersect anterior cortex.

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Final Message

• Complications often stem from technical errors.

• One small mistake can create a cascade of problems.

• Respect alignment, balance, exposure, and fixation principles.

• Meticulous technique prevents most failures.