Patella Fracture S82.009A 822.0

Displaced patella fracture lateral view xray

Displaced patella fracture A/P view

ORIF patella fracture lateral view xray

ORIF patella fracture A/P xray

synonyms: patellar fracture
Patella Fracture ICD-10

Patella Fracture ICD-9

  • 822.0 (fracture of patella, closed)
  • 822.1 (open)

Patella Fracture Etiology / Epidemiology / Natural History

Patella Fracture Anatomy

  • Patella = sesamoid bone within the extensor mechanism of the knee.
  • Bipartite patella ; present in @2% of patients.

Patella Fracture Clinical Evaluation

  • Knee pain, effusion usually after a direct blow to the knee.
  • Inability to extend the knee.

Patella Fracture Xray / Diagnositc Tests

  • A/P, lateral , Merchant or sunrise view of the knee. Fracture is generally best seen on lateral view.
  • MRI: consider for patients with potential osteochondral fracture. Generally not needed.
  • Intra-articular local anesthetic injection: Consider to confirm extensor mechanism is intact in patients in which pain precludes adequate physical exam.

Patella Fracture Classification / Treatment

  • Nondisplaced, intact extensor mechanism (generally vertical fractures)
    -Treatment = WBAT in knee brace locked in extention, or cylinder cast.
  • Displaced, extensor mechanism disrupted, transverse fracture
    -Treatment = ORIF with cannulated screws and tension band wire / fiberwire.
  • Displaced, extensor mechanism disrupted, inferior pole fracture
    -Treatment = partial patellectomy (distal pole) and reattachment of the patellar tendon through drill holes. Must maintain Insall-Salvati ratio around 1.0.
  • Displaced periprosthetic patella fracture with intact extensor mechanism.  Poor clinical results with ORIF due to patella osteonecrosis. Recommend immobilization in extension either with a long-leg cast or knee immobilizer. (Berry DJ. Patellar fracture following total knee arthroplasty. J Knee Surg. 2003 Oct;16(4):236-41)

Patella Fracture Associated Injuries / Differential Diagnosis

Patella Fracture Complications

Patella Fracture Follow-up Care

  • Post-op: knee brace locked in extention, WBAT in brace
  • 7-10 Days: Wound check, confirm reduction on xray. Consider allowing knee ROM to some degree based on stability of fixation at surgery.
  • 6 Weeks: Evaluate xrays for union. Advance ROM
  • 3 Months: progress with ROM and strengthening
  • 6 Months: review xrays, return to full activity / sport
  • 1Yr: f/u xrays, assess outcome.

Patella Fracture Review References