Patella (Knee Cap) Fracture
Injury: Patella Fracture, Knee Cap Fracture
Mechanism: Typically occurs with a direct force to the knee, such as a fall directly to the ground. However, can occur from the pull of the muscles on the knee cap in opposite directions.
Exam: Athletes will typically have swelling over the entire knee (effusion). Also they will be very tender to the touch directly over the knee cap. An experienced clinician will find that the ligaments of the knee are usually not torn.
Treatment: The treatment depends on the direction of the fracture, as well as the spacing between the fracture fragments. If the fracture fragments are greater than 2 mm apart, surgery should be considered. A patella fracture that goes vertically (top to bottom) typically can have less aggressive treatment as the fragments are less likely to pull away from each other. However, a patella fracture that is horizontal (side to side) needs to be treated with aggressive restriction of bending the knee to limit any further separation of the fragments. Typical immobilization should be around 4-6 weeks.
Return: Return to play after a fracture varies significantly based on the severity of the fracture and the overall health of the individual. In a young and healthy individual, typical healing time is estimated to be around 8 weeks if treated non-surgically.
Sports Considerations: If the fracture is treated non-surgically, one of the key factors associated with return to play is the direction of the fracture. When the fracture is horizontal there will be tugging on both sides of the fracture and therefore return to play will be longer and more gradual. If the fracture is vertical, the length of time until full return is usually less, as there will be less forces on the healing fragments of the fracture.
Vertical Fracture of Patella
Horizontal Fracture of Patella