What is the initial treatment for a patient with a patellar dislocation?

Initial Management of Patellar Dislocation

The initial treatment for a patient with patellar dislocation should be prompt closed reduction to relieve pain and prevent further damage. 1

Diagnostic Approach

Before proceeding with reduction, appropriate imaging should be obtained:

• First-line imaging: Radiographs including anteroposterior (AP), lateral, and patellofemoral (sunrise/Merchant) views to assess for associated fractures 1, 2
• Additional weight-bearing axial views may help assess patellofemoral kinematics 1

Reduction Technique

1. Closed reduction procedure:

   • Position the patient supine
   • Flex the knee to approximately 90°
   • Apply an anterior drawer force to the tibia
   • Apply gentle pressure to the lateral aspect of the patella to guide it back into the trochlear groove 3
   • Light sedation or analgesia is typically required for patient comfort

2. Special considerations:

   • Some dislocations may be irreducible on initial attempts, particularly if a fracture is present 4
   • In cases of irreducible dislocation, CT imaging is valuable to identify impediments to reduction 4
   • Manipulation under anesthesia in the operating room may be necessary for complex cases 4

Post-Reduction Management

After successful reduction:

1. Immobilization:

   • Apply a hinged knee brace set at 0° to 90° 3
   • Maintain immobilization with a neoprene non-hinged knee brace for approximately 4 weeks 1

2. Rehabilitation:

   • Begin weight-bearing as tolerated the day after reduction 3
   • Initiate physical therapy focusing on quadriceps strengthening 1
   • Gradually return to activities as symptoms allow

Complications and Follow-up

• Recurrence risk: Up to 40% of patients experience recurrent dislocation after a first-time event 1, 5
• Monitoring: Follow patients for signs of recurrent instability or subluxation
• Advanced imaging: Consider MRI if there is concern for concomitant soft tissue injuries or osteochondral fractures 1

Surgical Considerations

• Most first-time dislocations are successfully treated non-operatively 6
• Surgical intervention is typically reserved for recurrent dislocations 1, 5
• Options include Medial Patellofemoral Ligament (MPFL) reconstruction, tibial tuberosity transfer procedures, and trochleoplasty in cases of severe trochlear dysplasia 1

Common Pitfalls to Avoid

• Failing to obtain proper imaging to rule out associated fractures or osteochondral injuries 1
• Inadequate pain management during reduction attempts
• Prolonged immobilization leading to quadriceps atrophy and decreased range of motion 1
• Missing signs of vascular injury, particularly in cases of traumatic dislocation

By following this approach, most patellar dislocations can be effectively managed with good functional outcomes.