What are Knee Stress Fractures?

Stress fractures of the patella or knee are very rare. Approximately two out of 10,000 athletes may experience a patella stress fracture. Initial symptoms include activity-related pain and then a fatigue stress fracture after minor trauma. The term insufficiency stress fracture is used for cases where the patella is weakened previously such as after patella resurfacing surgery.

Causes of Stress Fractures of the Knee

Typically, stress fractures of the knee are caused by:

• Exposures to forces applied in a repetitive, rhythmic, and sub-threshold manner
• Fatigue or insufficiency
• A combination of muscular weakness, which initiates a disturbance in bone remodeling

What are the Signs and Symptoms of a Stress Fracture of the Knee?

The main symptom of a stress fracture in the knee involves a worsening anterior knee pain followed by a popping sound if the stress fracture displaces acutely.

How is the Condition Diagnosed?

Radiographs (X-rays) are frequently normal. Your doctor may order a bone scan and MRI to confirm the diagnosis.

Treatment of Stress Fractures of the Knee

Treatment mainly depends on the extent of the fracture, whether complete or incomplete, or displaced. Incomplete fractures may be treated with activity modification alone. Your doctor may call for an immediate cessation of activities that place stress on the bone.

Additionally, your doctor may recommend:

• Modification of activities in order to relieve symptoms
• Crutches (in mild cases) until the symptoms resolve
• Complete rest if the fracture area is large

Complete fractures require immobilization until healing occurs. For displaced fractures, your doctor may opt for operative reduction and internal fixation to restore natural biomechanics. For full recovery, prolonged rehabilitation will be required.