A patellar fracture is a complete or incomplete break of the patella (kneecap). Most fractures of the patella are accompanied by a sprain or rupture of ligaments, ligament-like tissue (retinaculum), or tendons attached to the patella.
What Is a Patella Fracture?
A patella fracture is a complete or incomplete break of the patella, or kneecap. The injury may also involve the ligaments, retinaculum, or tendons attached to the patella.
Causes and Risk Factors
Patella fractures typically result from a fall directly on the patella and the front of the knee.
Risk factors include:
- Contact sports, especially football, hockey, or soccer
- Basketball
- Motor sports
- Osteoporosis or other bone abnormalities
- Metabolic disorders, hormone problems, and nutritional deficiencies and disorders
- Poor physical conditioning, including strength and flexibility
- Poor balance
Symptoms
Common signs and symptoms of a patella fracture include:
- Severe pain in the knee at the time of injury
- Tenderness and swelling in the knee
- Pain when trying to move the knee
- Inability to straighten a bent knee under its own power
- Catching or locking of the knee
- Bleeding and bruising in the knee
- Difficulty bearing weight on the injured leg, especially when getting up from a sitting position, going up or down stairs, or jumping
- Visible deformity if the fracture is complete and the bone fragments separate enough to distort the normal contours of the leg
Treatment
Initial treatment consists of elevating the leg and applying ice to relieve pain and reduce swelling.
For nondisplaced fractures that are in proper alignment, four to six weeks of brace immobilization may be appropriate.
For displaced fractures that are out of alignment, surgery is usually recommended to reduce and fix the fracture fragments in the proper position and best restore the smooth cartilage surface of the patella. Surgical fixation may use sutures, wires, screws, or plates to stabilize the fracture fragments. When possible, Dr. Chudik prefers suture fixation to avoid complications from painful hardware.
After immobilization, with or without surgery, stretching and strengthening of the injured joint and weakened surrounding muscles are necessary. This may be done with or without the assistance of a physical therapist or athletic trainer.
Recovery and Outcomes
Outcomes for patella fractures depend on the severity of the fracture, injury to the surrounding soft tissue and cartilage, and the patient’s ability to recover strength and function.
Nondisplaced, well-aligned and stable fractures are treated without surgery and generally have a better prognosis than high-energy, displaced, separated and unstable fractures. Patella fractures generally heal well and have good outcomes. Post-traumatic arthritis of the patellofemoral compartment of the knee joint commonly develops following patella fractures.
Potential complications include:
- Failure to heal (nonunion)
- Healing in a poor position (malunion)
- Avascular necrosis (bone death) due to interruption of the blood supply to the bone
- Infection, especially when the skin is broken over the fracture site
- Post-traumatic arthritis
- Prolonged healing time if activity is resumed too quickly
- Persistent pain with sitting, rising from a sitting position, going up or down stairs or hills, jumping, and running
- Stiff knee
- Muscle atrophy and weakness
- Risks of surgery, including infection, bleeding, injury to nerves resulting in numbness, weakness, or paralysis, the need for further surgery, and pain from wires or screws used to fix the fracture
When to See Dr. Chudik
If you are concerned about a possible patella fracture, schedule an evaluation with Dr. Chudik.
Call 630-324-0402, request an appointment online, or email contactus@chudikmd.com.