What is the recommended orthotic (orthopedic brace) for a patient with a possible ligamentous injury to the knee?

Functional Knee Brace is Recommended for Possible Ligamentous Knee Injury

For a patient with possible ligamentous knee injury to the knee with normal X-rays but pain and swelling, a functional knee brace is strongly recommended as the most appropriate orthotic device. 1

Types of Knee Braces and Their Indications

Functional Knee Braces

• Primary recommendation for suspected ligamentous injuries
• Designed to reduce knee instability following ligament injury
• Provides control of external knee rotation and anteroposterior joint translation 1
• Helps control knee hyperextension and augments knee proprioception
• Available in "hinge-post-shell" or "hinge-post-strap" designs 1

Patellofemoral Braces

• Only indicated for patellar subluxation/dislocation or patellofemoral disorders
• Not appropriate for suspected ligamentous injuries 1

Prophylactic Knee Braces

• Used primarily for prevention rather than treatment
• Not recommended for acute ligamentous injuries 1

Selecting the Appropriate Functional Knee Brace

Key Features to Consider:

1. Length: Choose the longest brace that comfortably fits the patient's leg for optimal protection 1
2. Design: "Hinge-post-shell" designs provide better tibial-displacement control and greater rigidity than strap-based designs 1
3. Fit: Ensure proper placement of hinges relative to femoral condyles for optimal performance 1
4. Extension limitation: Consider setting 10-20 degrees of extension limitation to minimize hyperextension of the knee joint 1

Sizing Options:

• Presized models: Appropriate for most ER patients

  • Sized by measuring thigh circumference 6 inches above mid-patella
  • More cost-effective and immediately available
  • Suitable for patients with changing limb girths during rehabilitation 1

• Custom models: Not necessary for initial management in the ER

  • Only needed for abnormal limb contours or high-level athletes
  • More expensive and not immediately available 1

Clinical Benefits of Functional Knee Bracing

Functional knee braces provide several benefits for patients with suspected ligamentous injuries:

• Control of external knee rotation and anteroposterior joint translation
• Protection of injured ligaments during healing
• Enhanced knee proprioception
• Subjective improvements in knee stability and function
• Reduced pain during activities 1, 2

Important Considerations and Pitfalls

1. Patient Education: Explain that the brace is a temporary support, not a substitute for proper rehabilitation

2. Proper Application: Ensure the brace is correctly applied with:

   • Regular tightening of straps to prevent migration
   • Proper placement of hinges relative to femoral condyles 1

3. Common Pitfalls to Avoid:

   • False sense of security: Warn patients that braces may impart a false sense of confidence 1
   • Energy expenditure: Some patients may experience increased fatigue with prolonged use 1
   • Skin irritation: Monitor for skin problems, especially with prolonged use

4. Follow-up Care: Emphasize the importance of:

   • Orthopedic follow-up to confirm diagnosis and adjust treatment plan
   • Rehabilitation exercises to strengthen supporting muscles

Conclusion for Emergency Department Management

For a patient with possible ligamentous knee injury in the ER setting with normal X-rays but pain and swelling, a presized functional knee brace is the most appropriate orthotic device to provide stability, control pain, and protect the injured structures while awaiting definitive diagnosis and treatment.