Treatment of Fractured Patella
Treatment of patella fractures requires a balanced approach between operative and non-operative management based on fracture displacement, comminution pattern, and extensor mechanism integrity, with surgical fixation recommended for displaced fractures to restore articular congruity and knee function. 1
Initial Assessment and Decision-Making
Obtain standard radiographs (anteroposterior, lateral, and axial views) to assess:
- Fracture displacement (>2-3mm articular step-off or fragment separation) 2
- Fracture pattern (transverse, comminuted, vertical, or avulsion) 2
- Extensor mechanism integrity - this is the critical determinant: inability to perform straight leg raise mandates surgical intervention 2
Non-Operative Management
Indicated for non-displaced fractures (<2-3mm displacement) with intact extensor mechanism: 3, 2
- Immobilization in extension with cast or brace for 4-6 weeks 3
- Early quadriceps isometric exercises to prevent muscle atrophy 2
- Serial radiographs to monitor for displacement 2
- Progressive weight-bearing as tolerated with brace protection 2
Surgical Management
Indications for Surgery
Operate when any of the following are present: 2
- Articular displacement >2-3mm 2
- Fragment separation >3mm 2
- Disrupted extensor mechanism (inability to extend knee or perform straight leg raise) 2
- Open fractures 2
Surgical Technique Selection
For simple transverse (2-part) fractures: 2
- Modified tension band wiring remains standard, ideally combined with cannulated screw fixation for biomechanical superiority 2
- Alternatively, percutaneous cable pin systems may reduce complications compared to open tension band wiring, though evidence quality is very low 3
For comminuted or multi-fragment fractures: 4, 5, 2
- Angular stable locking patella plates are increasingly preferred - they provide superior mechanical stability, reduce loss of fixation, and improve functional outcomes compared to tension band wiring 4
- Plates allow anatomic restoration of retropatellar articular surface critical for long-term function 2
- Consider adjunct circular cerclage wiring (metal or FiberWire) to increase fixation stability and decrease re-dislocation risk 2
- Small fragment screws for interfragmentary compression in appropriate fracture patterns 2
For distal pole avulsion fractures: 2
- Fix with small fragment screws and protect with transtibial McLaughlin cerclage 2
Patellectomy (partial or complete) should be reserved only as salvage procedure due to severe functional impairment 2
Postoperative Management
Critical components include: 1
- Appropriate pain management 1
- Antibiotic prophylaxis 1
- Early mobilization to prevent arthrofibrosis and cartilage degeneration 2
- Early introduction of physical training and muscle strengthening 1
- Progressive range of motion exercises - avoid prolonged immobilization 2
- Regular wound assessment 1
Rehabilitation Protocol
Implement structured rehabilitation: 1
- Early postfracture quadriceps strengthening 1
- Long-term continuation of balance training 1
- Multidimensional fall prevention in elderly patients 1
Common Pitfalls and Complications
Be aware of frequent complications: 6
- Symptomatic hardware requiring removal (common with tension band wiring) 6
- Loss of fixation (reduced with locking plate technology) 4
- Arthrofibrosis from delayed mobilization 2
- Posttraumatic arthritis 6
- Extensor mechanism insufficiency 6
- Nonunion and infection 6
Patients over 50 years require additional evaluation: 1
- Systematic assessment for osteoporosis and subsequent fracture risk 1
- DXA scanning of spine and hip 1
- Calcium and vitamin D supplementation 1
- Consider pharmacological osteoporosis treatment to prevent future fractures 1
Special Considerations
In elderly or osteoporotic patients: 4
- Locking plate technology particularly beneficial due to angular stability in poor bone quality 4
- Consider orthogeriatric co-management for patients with fragility fractures 1
Functional expectations: 4