Summary about Disease
Patella dislocation occurs when the patella (kneecap) slips out of its normal position in the trochlear groove of the femur (thigh bone). It can be a partial dislocation (subluxation) or a complete dislocation. This can happen due to trauma, anatomical factors, or muscle imbalances. Repeated dislocations can lead to damage to the cartilage and ligaments in the knee.
Symptoms
Sudden giving way of the knee
Visible displacement of the kneecap (it may be obviously out of place)
Intense pain in the knee
Popping or snapping sensation at the time of injury
Swelling around the knee joint
Inability to straighten the leg
Tenderness along the inside of the kneecap
Causes
Trauma: Direct blow to the knee, twisting injury
Anatomical Factors:
Shallow trochlear groove (groove in the femur where the kneecap sits)
Patella alta (high-riding patella)
Increased Q-angle (angle between the quadriceps muscle and the patellar tendon)
Femoral anteversion (increased inward twisting of the thigh bone)
Muscle Imbalances: Weak quadriceps (especially the vastus medialis oblique - VMO) muscle
Ligament Laxity: General joint hypermobility or lax ligaments
Genetic Predisposition: Some individuals may be more prone to dislocations due to inherited anatomical factors.
Medicine Used
Pain relievers: Over-the-counter analgesics like ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) for pain management. Prescription pain medications (opioids) may be used for severe pain, but are generally avoided long-term due to the risk of dependence.
Anti-inflammatory medications: NSAIDs (Non-steroidal anti-inflammatory drugs) like ibuprofen or naproxen (Aleve) to reduce inflammation and pain.
Muscle relaxants: May be prescribed for muscle spasms surrounding the knee.
Is Communicable
No, patella dislocation is not a communicable disease. It is not caused by a virus, bacteria, or other infectious agent and cannot be spread from person to person.
Precautions
Strengthening Exercises: Focus on strengthening the quadriceps muscles, especially the VMO.
Proper Warm-up: Always warm up thoroughly before engaging in physical activities.
Bracing: Use a knee brace, especially during sports or activities that put stress on the knee.
Avoid High-Risk Activities: If prone to dislocations, modify or avoid activities that involve twisting or pivoting movements.
Maintain a Healthy Weight: Excess weight puts additional stress on the knee joint.
Proprioceptive Training: Exercises to improve balance and coordination.
Proper Footwear: Wear supportive shoes that provide good stability.
Address Anatomical Issues: If anatomical issues contribute to dislocations, consult with a physician regarding possible interventions.
How long does an outbreak last?
Patella dislocation is not an outbreak-related condition. It is an injury, not an infectious disease, so the concept of an "outbreak" does not apply. The "duration" refers to the recovery time from a single dislocation event. This can range from weeks to months, depending on the severity of the injury and the treatment approach.
How is it diagnosed?
Physical Examination: A doctor will examine the knee for swelling, tenderness, and range of motion. They will assess the stability of the patella and check for any anatomical abnormalities.
Medical History: The doctor will ask about the circumstances surrounding the injury, previous dislocations, and any predisposing factors.
X-rays: To rule out fractures and assess the position of the patella.
MRI (Magnetic Resonance Imaging): To evaluate soft tissue damage, such as ligament tears (e.g., medial patellofemoral ligament – MPFL), cartilage damage, and the condition of the surrounding structures.
CT Scan (Computed Tomography): Can be used to better visualize bone abnormalities.
Timeline of Symptoms
Immediately After Dislocation: Sudden pain, giving way of the knee, visible displacement of the patella.
Within Hours: Swelling, inability to straighten the leg, tenderness.
Days 1-7: Pain and swelling gradually decrease with rest, ice, compression, and elevation (RICE). Bruising may appear.
Weeks 2-8: Gradual return of range of motion and strength with physical therapy. Pain should continue to decrease.
Months 2-6: Full return to activities, depending on the severity of the injury and adherence to rehabilitation.
Important Considerations
Recurrent Dislocations: Individuals who have experienced a patella dislocation are at higher risk for future dislocations.
MPFL Injury: The medial patellofemoral ligament (MPFL) is often torn during a patella dislocation. The severity of the MPFL injury influences treatment decisions.
Cartilage Damage: Repeated dislocations can lead to cartilage damage, increasing the risk of osteoarthritis.
Surgery: Surgery may be necessary for recurrent dislocations, severe MPFL tears, or significant cartilage damage. Common surgical procedures include MPFL reconstruction, tibial tubercle osteotomy, and trochleoplasty.
Physical Therapy: Physical therapy is crucial for regaining strength, range of motion, and stability after a dislocation.
Long-Term Management: Even after successful treatment, ongoing management, including exercise and bracing, may be necessary to prevent future dislocations and minimize long-term complications.