What are the next steps in managing a suspected Quadriceps Tendon Rupture?

Management of Suspected Quadriceps Tendon Rupture

Complete quadriceps tendon ruptures require early surgical repair to achieve optimal functional outcomes, while partial tears with intact extensor mechanism may be managed conservatively. 1

Diagnostic Approach

Clinical Examination

• Look for the classic triad:
  • Acute knee pain
  • Inability to actively extend the knee
  • Palpable suprapatellar gap or defect 2
• Assess for extensor mechanism deficit by asking the patient to perform a straight leg raise

Imaging Studies

1. Plain radiographs should be obtained first to:

   • Identify "patella baja" (low-riding patella)
   • Detect any associated bony avulsion fractures
   • Look for suprapatellar calcifications 3

2. MRI is the gold standard for confirmation and surgical planning:

   • Determines extent of tear (partial vs. complete)
   • Shows degree of tendon retraction
   • Identifies location of rupture (most commonly 1-2 cm above patella) 1

3. Ultrasound can be a useful alternative if MRI is unavailable:

   • Less expensive and allows dynamic assessment
   • Operator-dependent but can differentiate partial from complete tears

Management Algorithm

For Complete Ruptures:

1. Urgent surgical repair (within days of injury):

   • Delayed repair leads to worse outcomes and increased complications 1
   • Primary repair techniques include:
     • Transosseous tunnel repair (most common)
     • Suture anchor repair
   • Both techniques yield excellent outcomes with >90% return to pre-injury function 1

2. Post-operative Protocol:

   • Initial immobilization in extension for 3-10 weeks
   • Progressive rehabilitation to address quadriceps atrophy and knee stiffness

For Partial Ruptures with Intact Extensor Mechanism:

1. Conservative management:
   • Immobilization with hinged knee brace
   • Protected weight-bearing
   • Progressive rehabilitation

Special Considerations

Risk Factors to Assess

• Age >40 years increases risk 2
• Medical conditions associated with tendon weakening:
  • Chronic kidney disease/dialysis 3
  • Diabetes
  • Gout
  • History of steroid use
  • Statin therapy 4

Potential Complications

• Quadriceps muscle atrophy (most common)
• Knee stiffness (most common)
• Heterotopic ossification (6.9%)
• Deep venous thrombosis/pulmonary embolism (2.5%)
• Rerupture rate (2%) 5
• Infections (1-1.2%) 5

Common Pitfalls to Avoid

• Delayed diagnosis - leads to tendon retraction and more difficult repair
• Misdiagnosis - can be confused with patellar tendon rupture
• Overlooking bilateral ruptures - more common in patients with systemic diseases
• Inadequate rehabilitation - can lead to persistent weakness and functional limitation

Early surgical intervention for complete tears is critical for restoring extensor mechanism function and preventing long-term disability, with excellent outcomes reported in over 90% of properly treated cases 1, 5.