What is the treatment for a patella dislocation?

Treatment of Patella Dislocation

Most first-time patellar dislocations should be managed conservatively with immobilization and physical therapy after excluding associated injuries that require surgery, such as osteochondral fractures or loose bodies. 1, 2, 3

Immediate Management

Reduction

• If the patella remains dislocated, perform immediate closed reduction to provide pain relief and restore knee function 4
• Reduction can be safely performed in the prehospital setting with a 92% success rate and minimal complications, typically reducing pain scores from 10/10 to 2/10 4
• After reduction, immobilize the knee in extension or slight flexion (typically 3 weeks) 5

Initial Diagnostic Workup

• Obtain standard radiographs (anteroposterior, lateral, and patellofemoral views) to assess for patellar fracture, osteochondral injury, and anatomic risk factors 6
• MRI is essential to identify associated injuries including osteochondral fractures, loose bodies, and medial patellofemoral ligament (MPFL) tears, which occur in nearly all acute dislocations 2, 3
• The MPFL is injured at its femoral attachment in the vast majority of cases 3

Treatment Algorithm

Indications for Surgical Intervention (Acute)

• Osteochondral fractures with loose bodies or displaced fragments 2, 3
• Large displaced osteochondral fragments that require fixation or removal 2
• Open reduction may be needed if closed reduction fails (rare) 5

Conservative Management (First-Line for Most Patients)

• Non-operative treatment is recommended for first-time dislocations without osteochondral injury, even in children and adolescents 1, 2
• Immobilization for approximately 3 weeks in a knee brace or immobilizer 5
• Progressive rehabilitation focusing on restoration of range of motion and quadriceps strengthening 2
• Orthotic devices may benefit patients with foot pronation or pes planus contributing to malalignment 7

Risk Assessment for Recurrence

• Evaluate for anatomic risk factors on imaging: trochlear dysplasia, increased tibial tubercle-trochlear groove distance (TT-TG), patella alta 3
• Counsel patients that recurrence risk exists, particularly in those with anatomic predisposing factors 1
• Lateral patellar displacement >50% of patellar width on examination is abnormal and suggests instability 3

Indications for Delayed Surgical Stabilization

• Reserve surgical stabilization (MPFL reconstruction, tibial tubercle osteotomy, trochleoplasty) for patients with recurrent instability after failed conservative management 1
• Surgery for first-time dislocation should not be routine, as there is a trend toward inappropriate operative intervention 2

Important Caveats

• Two-thirds of acute patellar dislocations occur in patients under 20 years old, typically during sports activities 3
• The most common mechanism is non-contact knee flexion with valgus stress (93% of cases) 3
• CT is useful for detailed assessment of axial malrotation and bony anatomy when surgical planning is needed 7
• The literature quality is poor with inadequate follow-up, making definitive conclusions difficult, but consensus supports initial conservative management 1
• Always exclude alternative or associated injuries (meniscal tears, ligament injuries, fractures) that may require different treatment 1