What is the management algorithm for a first-time patella dislocation?

Management Algorithm for First-Time Patellar Dislocation

The management of first-time patellar dislocation should be primarily conservative unless specific indications for surgery are present. This approach is supported by current evidence showing equivalent functional outcomes between surgical and non-surgical management for most patients with first-time dislocations 1.

Initial Assessment

• Radiographic Evaluation: Obtain anteroposterior and lateral knee radiographs as the initial imaging study 2

  • Add patellofemoral view for better evaluation of patellar position and potential fractures
  • Consider cross-table lateral view to detect lipohemarthrosis if intra-articular fracture is suspected

• Indications for Advanced Imaging:

  • MRI is indicated when there is suspicion of:
    • Osteochondral fracture
    • Substantial disruption of medial patellar stabilizers
    • Associated internal derangement

Treatment Algorithm

Conservative Management (First-Line Treatment)

1. Immobilization Phase (0-2 weeks):

   • Knee Brace: Use a removable knee brace that allows 0-30° of motion 3
   • Weight-Bearing: Partial weight-bearing with crutches as tolerated
   • Pain Management: NSAIDs (ibuprofen 1.2-2.4g daily or naproxen 500mg twice daily) 4
   • Cryotherapy: Ice application for 15-20 minutes every 2-3 hours for acute pain relief 4

2. Early Rehabilitation Phase (2-4 weeks):

   • Range of Motion: Progressive increase in allowed knee flexion
   • Exercises: Begin quadriceps strengthening with isometric exercises
   • Weight-Bearing: Progress to full weight-bearing as tolerated

3. Intermediate Rehabilitation Phase (4-8 weeks):

   • Brace Discontinuation: Typically at 4 weeks post-injury
   • Exercises: Progressive strengthening with focus on:
     • Vastus medialis obliquus strengthening
     • Hip abductor strengthening
     • Proprioceptive training
     • Eccentric strengthening exercises 4

4. Advanced Rehabilitation Phase (8-12 weeks):

   • Functional Training: Sport or occupation-specific exercises
   • Return to Activity Criteria:
     • Complete resolution of pain
     • Full range of motion
     • Strength symmetry >90% compared to uninjured side
     • Successful completion of functional tests 4

Surgical Management

Indications for Primary Surgical Intervention:

• Presence of osteochondral fracture
• Substantial disruption of the medial patellar stabilizers
• Laterally subluxated patella with normal alignment of contralateral knee
• Large loose bodies requiring removal 5

Surgical Considerations:

• MPFL (medial patellofemoral ligament) reconstruction is generally preferred over repair for better outcomes 6
• Address any underlying anatomical abnormalities that predispose to instability

Follow-Up Protocol

• 2-Week Follow-Up: Assess pain, swelling, and early range of motion
• 6-Week Follow-Up: Evaluate progress with rehabilitation and range of motion
• 12-Week Follow-Up: Assess readiness for return to full activities 4

Risk Assessment for Recurrent Dislocation

Factors associated with higher recurrence risk:

• Age <25 years
• Female gender
• Trochlear dysplasia
• Patella alta
• Increased TT-TG (tibial tubercle-trochlear groove) distance
• Generalized ligamentous laxity

Common Pitfalls to Avoid

• Prolonged Immobilization: Avoid immobilization beyond 4 weeks as it leads to quadriceps atrophy and worse functional outcomes 3
• Inadequate Rehabilitation: Failure to complete a structured rehabilitation program increases recurrence risk
• Missed Associated Injuries: Carefully evaluate for osteochondral injuries that may require surgical intervention
• Delayed Referral: Consider surgical consultation if no improvement after 6-8 weeks of conservative treatment 4

The evidence suggests that conservative management provides similar long-term outcomes to surgical intervention for most first-time patellar dislocations, with surgery primarily indicated for specific circumstances as outlined above 5, 7, 1.