What is the appropriate treatment for a patellar fracture sustained during a sudden slip and fall?

Treatment of Patellar Fracture from Slip and Fall

For a patellar fracture sustained during a sudden slip and fall, initial management should begin with standard radiographs (anteroposterior, lateral, and patellofemoral views), followed by surgical fixation for displaced fractures or conservative management with immobilization for non-displaced fractures. 1

Initial Diagnostic Approach

Obtain standard knee radiographs immediately as the first-line imaging modality when a patient presents with focal tenderness, effusion, or inability to bear weight after acute knee trauma. 1

• A minimum of two views (anteroposterior and lateral) should be obtained, with the lateral view at 25-30 degrees of flexion to visualize the patella in profile. 1
• Add a patellofemoral view specifically for suspected patellar fractures to better characterize the fracture pattern and assess for subluxation or dislocation. 1
• A cross-table lateral view with horizontal beam can visualize lipohemarthrosis, which is frequently seen with intra-articular fractures. 1

If radiographs are negative but clinical suspicion remains high for occult fracture, CT or MRI can detect radiographically occult fractures, though these are not routinely used as initial imaging. 1

Treatment Decision Algorithm

For Displaced Patellar Fractures:

Surgical fixation is the standard treatment for displaced patellar fractures to restore the extensor mechanism and articular surface congruity. 2, 3

• Modified tension band wiring technique provides the best results for transverse fractures, which are the most common pattern. 3
• Mini cancellous screw and lag-screw fixation should be used for vertical fractures. 3
• Combination of K-wire and circumferential cerclage wire fixation is appropriate for comminuted fractures. 3
• Patellectomy may be reserved only for severely comminuted fractures where no major fragments containing articular surface exist. 3

For Non-Displaced Fractures:

Conservative management with immobilization is appropriate when fracture displacement is minimal and the extensor mechanism remains intact. 2

Important Clinical Considerations

Assess for associated injuries that would mandate surgical intervention:

• Osteochondral fractures require surgical treatment regardless of patellar fracture displacement. 4, 5
• Substantial disruption of medial patellar stabilizers necessitates surgical repair. 4
• Free bodies visible on imaging should be treated surgically. 5

Evaluate for anatomic risk factors on imaging:

• Trochlear dysplasia and increased tibial tubercle-trochlear groove distance (TT-TG) are bony risk factors that may require correction. 5
• MRI provides information on cartilage and capsulo-ligamentous status for treatment planning. 5

Common Pitfalls to Avoid

Do not miss associated patellar dislocation: Lateral patellar subluxation can occur with fracture, and displacement by more than 50% of patellar width is abnormal and may require surgical stabilization. 5

Be aware of potential surgical complications: Open reduction and internal fixation carries risks including nonunion, infection, posttraumatic arthritis, arthrofibrosis, symptomatic hardware, and extensor mechanism insufficiency. 6

Ensure adequate post-operative rehabilitation: The quality of rehabilitation significantly affects outcomes following surgical treatment of patellar fractures. 3

Expected Outcomes

Surgical treatment of patellar fractures yields good results in approximately 55% of cases, moderate results in 35%, and poor results in 10% when evaluated at an average 24-month follow-up. 3 The majority of trauma severity, fracture type, surgical technique selection, and post-operative rehabilitation quality all significantly impact final outcomes. 3