Patella Maltracking: Understanding Causes, Symptoms, and Treatment

What is Patella Maltracking?

Patella maltracking refers to an abnormal movement pattern of the kneecap (patella) within the trochlear groove of the thigh bone (femur) during knee flexion and extension, often leading to pain and dysfunction.

Understanding the Patellofemoral Joint

The patellofemoral joint is the articulation between the patella (kneecap) and the femur (thigh bone). The patella is a sesamoid bone embedded within the quadriceps tendon, serving as a crucial lever arm that enhances the mechanical advantage of the quadriceps muscles, allowing for efficient knee extension.

For optimal function and health, the patella must glide smoothly and centrally within a specific groove on the end of the femur, known as the trochlear groove, as the knee bends and straightens. This precise movement ensures even distribution of forces across the joint surfaces and minimizes friction.

What Exactly is Patella Maltracking?

Patella maltracking, also known as patellar tracking disorder or patellofemoral dysfunction, occurs when the kneecap deviates from its normal, central path within the trochlear groove. Instead of gliding smoothly, the patella might shift excessively to one side (most commonly laterally, towards the outside of the knee), tilt, or rotate.

This abnormal movement can lead to increased friction and uneven pressure on the cartilage surfaces of the patella and femur. Over time, this can cause irritation, inflammation, and degenerative changes to the cartilage (a condition known as chondromalacia patellae or patellofemoral pain syndrome), resulting in pain and impaired knee function.

Common Causes of Patella Maltracking

Patella maltracking is often multifactorial, meaning several factors can contribute to its development. These can be broadly categorized as anatomical, muscular, and biomechanical.

• Anatomical Factors:

  • Shallow Trochlear Groove: If the groove in the femur is too shallow or flat, it provides less stability for the patella.
  • Patella Alta: A high-riding patella sits above the trochlear groove at rest, making it less stable and prone to maltracking.
  • Increased Q-Angle: The Q-angle (quadriceps angle) measures the angle between the quadriceps muscle and the patellar tendon. A larger than normal Q-angle (common in individuals with wider hips or knock-knees) increases the lateral pull on the patella.
  • Tight Lateral Retinaculum: The retinaculum are fibrous bands that help stabilize the patella. A tight lateral retinaculum can pull the patella excessively outwards.
  • Foot Pronation: Excessive inward rolling of the foot can alter the alignment of the entire leg, leading to increased internal rotation of the tibia and femur, which can contribute to patellar misalignment.

• Muscular Imbalances:

  • Weak Vastus Medialis Obliquus (VMO): The VMO is the inner part of the quadriceps muscle and plays a crucial role in pulling the patella medially (inward) to counteract the lateral pull of the vastus lateralis. Weakness in the VMO can lead to lateral maltracking.
  • Tight Iliotibial (IT) Band: A tight IT band, a thick band of fascia running along the outside of the thigh, can pull the patella laterally.
  • Weak Hip Abductors and External Rotators: Muscles like the gluteus medius and minimus, and the deep hip external rotators, are essential for stabilizing the pelvis and femur. Weakness in these muscles can lead to excessive internal rotation of the femur during movement, contributing to patellar maltracking.
  • Tight Hamstrings or Quadriceps: Imbalances in flexibility can alter the forces acting on the knee joint.

• Biomechanical Factors:

  • Poor Movement Patterns: Incorrect technique during activities like squatting, lunging, or running can place undue stress on the patellofemoral joint.
  • Overuse or Repetitive Stress: High-impact activities or sudden increases in training volume can overwhelm the joint's capacity and lead to irritation.
  • Previous Injury or Trauma: A direct blow to the kneecap or a previous patellar dislocation can damage the stabilizing structures and predispose to maltracking.

Recognizing the Symptoms

The symptoms of patella maltracking typically develop gradually and are often exacerbated by specific activities.

• Anterior Knee Pain: This is the most common symptom, usually felt around or behind the kneecap. The pain can be dull and aching or sharp, particularly during movement.
• Pain with Specific Activities:
  • Climbing or descending stairs.
  • Squatting or kneeling.
  • Prolonged sitting with bent knees ("theater sign").
  • Running, jumping, or other high-impact activities.
• Clicking, Popping, or Grinding Sensations (Crepitus): These sounds may be heard or felt during knee movement, indicating friction between the patella and femur.
• Feeling of Instability or "Giving Way": While less common than with true ligamentous instability, some individuals may feel as though their knee might buckle or give out.
• Mild Swelling: Less common, but may occur if there is significant inflammation or irritation within the joint.

Diagnosis of Patella Maltracking

A thorough diagnosis typically involves a combination of a detailed medical history, a physical examination, and sometimes imaging studies.

• Clinical Examination:
  • Patient History: The clinician will ask about your symptoms, activity levels, and any previous injuries.
  • Physical Assessment: This includes observing your gait and movement patterns, palpating the knee for tenderness, assessing the range of motion, and evaluating muscle strength and flexibility of the quadriceps, hamstrings, hip muscles, and core. The clinician will also assess patellar mobility and tracking, and measure the Q-angle.
• Imaging Studies:
  • X-rays: Used to evaluate the bony alignment of the knee, including patellar height (patella alta/baja) and the shape of the trochlear groove. Specialized views (e.g., Merchant view, sunrise view) can show patellar tilt or subluxation.
  • Magnetic Resonance Imaging (MRI): Provides detailed images of soft tissues, including cartilage, ligaments, and tendons, which can help assess for cartilage damage (chondromalacia), effusions, or ligamentous injuries.
  • Computed Tomography (CT) Scan: Less common but can be useful for detailed assessment of bony anatomy, particularly in cases of suspected trochlear dysplasia.

Management and Treatment Approaches

The primary goal of treatment for patella maltracking is to reduce pain, restore normal patellar tracking, and improve function. Conservative management is almost always the first line of approach.

• Conservative Management:
  • Rest and Activity Modification: Reducing or temporarily avoiding activities that aggravate symptoms.
  • Ice Application: To reduce pain and inflammation, especially after activity.
  • Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): Over-the-counter medications like ibuprofen can help manage pain and inflammation.
  • Physical Therapy: This is the cornerstone of conservative treatment. A physical therapist will design an individualized program focusing on:
    • Strengthening Exercises: Targeting the vastus medialis obliquus (VMO), gluteal muscles (abductors and external rotators), and core stabilizers to improve lower extremity alignment and control.
    • Flexibility Exercises: Stretching tight muscles such as the quadriceps, hamstrings, IT band, and hip flexors.
    • Manual Therapy: Techniques to improve patellar mobility and reduce soft tissue restrictions.
    • Neuromuscular Re-education: Training to improve movement patterns during functional activities like squatting, lunging, and stair climbing.
    • Patellar Taping or Bracing: Kinesiology tape or specialized braces can help provide immediate support and improve patellar positioning during activity.
    • Orthotics: Custom or over-the-counter shoe inserts can help address excessive foot pronation and improve lower limb alignment.
• Injections:
  • Corticosteroid Injections: Rarely used for long-term management due to potential side effects on cartilage, but can offer temporary pain relief for acute inflammation.
  • Hyaluronic Acid Injections: Sometimes used for patellofemoral osteoarthritis, but evidence for patella maltracking specifically is limited.
• Surgical Intervention: Surgery is typically considered only after a prolonged course of conservative treatment (at least 6-12 months) has failed to relieve symptoms, or in cases of recurrent patellar dislocations. Surgical procedures aim to realign the patella and may include:
  • Lateral Retinacular Release: Cutting the tight lateral retinaculum to reduce outward pull on the patella.
  • Medial Patellofemoral Ligament (MPFL) Reconstruction: Reconstructing the primary ligament that stabilizes the patella medially, often done after patellar dislocations.
  • Tibial Tubercle Osteotomy: Repositioning the bony attachment of the patellar tendon on the tibia to alter the patellar tracking.
  • Trochleoplasty: Reshaping the trochlear groove to provide a deeper and more stable path for the patella.

Prevention Strategies

While not all cases of patella maltracking are preventable, certain strategies can significantly reduce the risk, especially for those involved in sports or repetitive activities.

• Balanced Strength Training: Focus on strengthening the entire kinetic chain, including the quadriceps (with emphasis on VMO activation), hamstrings, gluteal muscles (abductors, extensors, external rotators), and core.
• Maintain Flexibility: Regularly stretch major muscle groups around the hips and knees, including quadriceps, hamstrings, hip flexors, and the IT band.
• Optimize Biomechanics: Learn and practice proper form for exercises and daily movements (e.g., squatting with knees tracking over toes, avoiding excessive knee valgus).
• Appropriate Footwear: Wear shoes that provide adequate support and cushioning, and consider orthotics if you have significant foot pronation.
• Gradual Progression: Avoid sudden increases in the intensity, duration, or frequency of physical activity to allow your body to adapt.

When to Seek Professional Help

It is advisable to consult a healthcare professional, such as an orthopedic surgeon, sports medicine physician, or physical therapist, if you experience:

• Persistent or worsening knee pain that interferes with daily activities.
• Pain that does not improve with rest and basic self-care measures.
• A feeling of instability, "giving way," or recurrent dislocations of the kneecap.
• Significant swelling or locking of the knee joint.

Conclusion

Patella maltracking is a common condition characterized by abnormal movement of the kneecap within its femoral groove, leading to pain and dysfunction. While it can be debilitating, it is a highly manageable condition. Understanding the underlying anatomical, muscular, and biomechanical factors is key to effective treatment. With a comprehensive approach focusing on conservative management, particularly physical therapy, most individuals can achieve significant pain relief and return to their desired activities. Surgical intervention is reserved for severe cases or when conservative measures fail. Early diagnosis and adherence to a tailored rehabilitation program are crucial for optimal outcomes and preventing long-term complications.