A 17 Year Old Female Dislocated Her Patella

A dislocated patella, or kneecap, can be a painful and frightening experience, especially for an active teenager. For a 17-year-old female, understanding the causes, symptoms, and treatment options for a dislocated patella is crucial for a smooth recovery and preventing future occurrences. This article delves into the specifics of patellar dislocation in a young woman, exploring the anatomy, mechanism of injury, diagnosis, treatment, rehabilitation, and prevention strategies.

Understanding Patellar Dislocation

The patella, or kneecap, is a small bone that sits in a groove at the end of the femur (thighbone) called the trochlear groove. It glides up and down within this groove as the knee bends and straightens. The patella is held in place by various ligaments, tendons, and muscles, most importantly the quadriceps muscles and the patellofemoral ligaments. Patellar dislocation occurs when the patella slips out of this groove, usually laterally (to the outside of the knee).

Predisposing Factors in Young Females

Several factors make young women more susceptible to patellar dislocations compared to their male counterparts:

• Anatomical Differences: Women tend to have a wider pelvis, which results in a larger Q-angle. The Q-angle is the angle between the quadriceps muscle and the patellar tendon. A larger Q-angle increases the lateral pull on the patella, making it more prone to dislocation.
• Muscle Imbalances: Weakness in the vastus medialis oblique (VMO), the inner part of the quadriceps muscle, can contribute to patellar instability. The VMO helps to pull the patella medially (inward) and counteract the lateral pull.
• Ligamentous Laxity: Some individuals, particularly young women, have naturally more flexible ligaments. This ligamentous laxity can make the knee joint more unstable and increase the risk of dislocation.
• Shallow Trochlear Groove: The depth of the trochlear groove varies among individuals. A shallower groove provides less bony constraint for the patella, making it easier to dislocate. This condition is known as trochlear dysplasia.
• Patella Alta: This refers to a patella that sits higher than normal in the trochlear groove. This positioning can make the patella more susceptible to dislocation, especially during activities involving twisting or pivoting.

Causes and Mechanisms of Injury

Patellar dislocations can be caused by a direct blow to the knee, a sudden twisting motion, or a combination of factors. In a 17-year-old female, common scenarios that can lead to patellar dislocation include:

• Sports Injuries: Participating in sports that involve rapid changes in direction, such as basketball, soccer, volleyball, and dancing, increases the risk of patellar dislocation. A sudden pivot or landing awkwardly after a jump can force the patella out of its groove.
• Direct Trauma: A direct blow to the inside of the knee can push the patella laterally, causing it to dislocate.
• Pre-existing Instability: In some cases, the patella may dislocate due to minimal trauma if there is underlying instability due to anatomical factors or previous injuries.

Recognizing the Symptoms

The symptoms of a patellar dislocation are usually quite obvious and include:

• Sudden Pain: Intense pain in the knee at the time of the injury.
• Visible Deformity: The kneecap may be visibly out of place, sitting on the lateral side of the knee.
• Inability to Straighten the Knee: Difficulty or inability to fully extend the leg.
• Swelling: Rapid swelling around the knee joint.
• Tenderness: Tenderness to the touch along the medial side of the patella and around the knee.
• Popping Sensation: A feeling or sound of popping at the time of the injury.
• Locking: The knee may feel locked in a bent position.

Diagnosis and Evaluation

A thorough diagnosis is essential to determine the extent of the injury and guide the treatment plan. The diagnostic process typically involves:

• Physical Examination: The doctor will examine the knee for signs of instability, swelling, tenderness, and range of motion limitations. They will also assess the alignment of the patella and the surrounding structures.
• Medical History: The doctor will ask about the patient's medical history, including any previous knee injuries, predisposing factors, and the mechanism of injury.
• Imaging Studies:
  • X-rays: X-rays are used to rule out fractures and assess the position of the patella.
  • MRI (Magnetic Resonance Imaging): MRI is the gold standard for evaluating soft tissue injuries, such as ligament tears, cartilage damage (chondral or osteochondral defects), and damage to the medial patellofemoral ligament (MPFL), which is often injured during a patellar dislocation.

Treatment Options

The treatment for a dislocated patella depends on the severity of the injury, the presence of other associated injuries, and the patient's activity level.

Non-Surgical Treatment

In many cases, especially for first-time dislocations without significant associated injuries, non-surgical treatment is the initial approach. This typically involves:

• Reduction: The patella may spontaneously reduce (go back into place) on its own. If not, a doctor can gently maneuver the patella back into its normal position. This is called a closed reduction.
• Immobilization: After reduction, the knee is typically immobilized in a brace to allow the injured tissues to heal. The duration of immobilization varies depending on the severity of the injury, but it is usually around 2-6 weeks.
• Pain Management: Pain medication, such as over-the-counter pain relievers or stronger prescription medications, may be prescribed to manage pain and inflammation.
• Physical Therapy: Physical therapy is a crucial component of non-surgical treatment. The goals of physical therapy include:
  • Reducing pain and swelling
  • Restoring range of motion
  • Strengthening the quadriceps muscles, particularly the VMO
  • Improving balance and proprioception (the body's sense of position in space)
  • Gradually returning to activities

Surgical Treatment

Surgery may be recommended in certain cases, such as:

• Recurrent Dislocations: If the patella dislocates multiple times, surgery may be necessary to stabilize the knee and prevent further dislocations.
• Significant Associated Injuries: If there are significant injuries to the ligaments, cartilage, or other structures in the knee, surgery may be required to repair these injuries.
• Anatomical Abnormalities: If there are underlying anatomical abnormalities, such as a shallow trochlear groove or patella alta, surgery may be performed to correct these issues.

Several surgical procedures can be used to treat patellar instability:

• MPFL Reconstruction: The medial patellofemoral ligament (MPFL) is the primary stabilizer of the patella, and it is often torn during a dislocation. MPFL reconstruction involves replacing the torn ligament with a graft, which can be taken from another part of the patient's body (autograft) or from a donor (allograft).
• Tibial Tubercle Transfer (TTT): This procedure involves moving the tibial tubercle (the bony prominence on the front of the shinbone where the patellar tendon attaches) to a different position. This can help to improve the alignment of the patella and reduce the lateral pull on the kneecap.
• Trochleoplasty: This procedure involves deepening the trochlear groove to provide more bony constraint for the patella. This is typically performed in patients with trochlear dysplasia.
• Lateral Release: This procedure involves cutting the lateral retinaculum, a band of tissue on the outside of the knee that can contribute to lateral patellar tracking. This is less commonly performed than other procedures and is usually done in conjunction with other surgeries.

Rehabilitation After Surgery

Rehabilitation after surgery is essential for a successful outcome. The rehabilitation program will be tailored to the specific procedure performed and the patient's individual needs. The general goals of rehabilitation include:

• Protecting the healing tissues
• Controlling pain and swelling
• Restoring range of motion
• Strengthening the muscles around the knee
• Improving balance and proprioception
• Gradually returning to activities

The rehabilitation process typically involves several phases:

• Phase 1 (Weeks 0-2): Focus on pain and swelling control, gentle range of motion exercises, and isometric muscle contractions (contracting the muscles without moving the joint).
• Phase 2 (Weeks 2-6): Gradual increase in range of motion, strengthening exercises, and weight-bearing activities.
• Phase 3 (Weeks 6-12): Continued strengthening, balance training, and proprioceptive exercises.
• Phase 4 (Weeks 12+): Return to sport-specific activities and a gradual return to full activity.

It is important to follow the physical therapist's instructions carefully and to progress at a safe pace. Rushing the rehabilitation process can increase the risk of re-injury.

Prevention Strategies

Preventing patellar dislocations is crucial, especially for individuals with predisposing factors. Several strategies can help to reduce the risk of dislocation:

• Strengthening Exercises: Strengthening the quadriceps muscles, particularly the VMO, is essential for patellar stability. Other important muscles to strengthen include the hamstrings, hip abductors, and hip external rotators.
• Stretching Exercises: Stretching the muscles around the knee, including the quadriceps, hamstrings, and calf muscles, can help to improve flexibility and reduce the risk of injury.
• Proper Warm-up: Warming up properly before exercise can help to prepare the muscles for activity and reduce the risk of injury.
• Bracing: Wearing a knee brace can provide additional support and stability to the knee, especially during high-risk activities.
• Proper Footwear: Wearing shoes that provide good support and stability can help to prevent injuries.
• Activity Modification: Avoiding activities that place excessive stress on the knee, such as deep squats or lunges, can help to reduce the risk of dislocation.
• Proprioceptive Training: Exercises that improve balance and proprioception can help to improve knee stability and reduce the risk of injury.
• Addressing Anatomical Factors: In some cases, addressing underlying anatomical factors, such as patella alta or trochlear dysplasia, with surgical intervention may be necessary to prevent recurrent dislocations.

Psychological Considerations

A patellar dislocation can be a traumatic experience, both physically and emotionally. It is important to address the psychological aspects of the injury, especially in a young female athlete. Some common psychological challenges include:

• Fear of Re-injury: The fear of dislocating the patella again can be a significant barrier to returning to activity.
• Anxiety and Depression: The injury can lead to anxiety and depression, especially if it interferes with participation in sports or other activities.
• Loss of Confidence: The injury can lead to a loss of confidence in one's physical abilities.

It is important to seek support from family, friends, coaches, and healthcare professionals. A sports psychologist or therapist can also provide valuable support and guidance.

Long-Term Outlook

The long-term outlook for a 17-year-old female who has dislocated her patella depends on several factors, including the severity of the injury, the presence of associated injuries, the treatment approach, and adherence to the rehabilitation program.

With proper treatment and rehabilitation, most individuals can return to their previous level of activity. However, some individuals may experience recurrent dislocations, chronic pain, or stiffness. In these cases, additional treatment may be necessary.

It is important to follow up with a doctor regularly to monitor the progress of healing and to address any concerns or complications that may arise.

Conclusion

A dislocated patella can be a challenging injury, especially for a 17-year-old female. Understanding the causes, symptoms, and treatment options is crucial for a smooth recovery and preventing future occurrences. By addressing predisposing factors, seeking prompt medical attention, following a comprehensive rehabilitation program, and implementing prevention strategies, young women can overcome this injury and return to their active lifestyles. Remember to prioritize proper strengthening, stretching, and proprioceptive exercises, and don't hesitate to seek support from healthcare professionals and loved ones throughout the recovery process.