When is a hinged knee brace indicated?

Indications for Hinged Knee Braces

Hinged knee braces are primarily indicated for providing additional support after ACL surgery, supporting mild to moderate PCL or MCL instability, and controlling knee hyperextension. 1

Types of Hinged Knee Braces and Their Specific Indications

Functional Knee Braces

Functional hinged knee braces are indicated for:

• Post-ACL reconstruction support to reduce strain in the ACL graft 1
• Support for mild to moderate PCL or MCL instability 1
• Control of knee hyperextension 1
• Additional stability following ligamentous knee injury during activities requiring rapid direction changes 1

Prophylactic Knee Braces

Prophylactic hinged knee braces are indicated for:

• MCL protection against valgus knee stresses 1
• Re-injury protection after previous MCL injury 1
• Athletes at high risk for MCL injury (particularly football linemen) 1

Patellofemoral Braces

Patellofemoral hinged braces are indicated for:

• Patellar subluxation and/or dislocation 1
• Patellar translation 1
• Nondisplaced patellar fractures requiring 4-6 weeks of functional support 2

Contraindications for Hinged Knee Braces

Hinged knee braces are contraindicated in:

• Unstable knees requiring operative therapy 1
• Complicated multi-directional knee injuries such as corner injuries 1
• Knee disorders unrelated to the patellofemoral joint (for patellofemoral braces) 1
• Limiting rotational control in ACL-deficient knees (for prophylactic braces) 1

Effectiveness and Limitations

Benefits

• Control of knee hyperextension and external rotation 1
• Augmented knee proprioception 1
• Reduced tibial rotation and knee anteroposterior translation in laboratory settings 1
• Improved patellar tracking during knee flexion and extension (patellofemoral braces) 1

Limitations

• Effectiveness decreases at physiologic stress levels - laboratory benefits often don't translate to real-world performance 1, 3
• Increased energy expenditure and decreased agility during prolonged use 1
• False sense of confidence following ACL reconstruction 1
• Effectiveness varies by flexion angle - 50% effective at 30° but only 4% effective at 90° of knee flexion 3

Practical Application Guidelines

Brace Selection

1. Choose the longest brace that fits the athlete's leg for maximum protection 1
2. For functional braces, select either custom or presized models:
   • Custom braces: Better for abnormal limb contours, high-level athletes, or enhanced comfort 1
   • Presized braces: Appropriate when cost or rapid availability is important 1
3. For patellofemoral braces, consider models with lateral hinges and adjustable patellar buttresses for active individuals 2

Proper Fitting

• Correctly place hinges relative to femoral condyles for optimal performance 1, 3
• Set 10-20 degrees of extension limitation to minimize hyperextension 1
• Regular tightening of straps to reduce unwanted migration 1
• Shave leg hair and fit brace closely to improve skin contact 1
• For patellar fractures, position buttress supports comfortably and align the patella in the center of any cutout 2

Evidence-Based Outcomes

Research on hinged knee braces shows mixed results:

• Post-ACL reconstruction patients showed no significant differences in IKDC scores or anteroposterior laxity between braced and non-braced groups at 4-year follow-up 4
• Non-braced patients reported significantly less pain during sports or heavy physical work (1.0 ± 1.2 vs 1.9 ± 1.4 on VAS) 4
• Functional braces provide significant stabilizing effects throughout the range of knee flexion, but effectiveness decreases in deeper flexion angles 3

Clinical Pearls and Pitfalls

Pearls

• Accurate sizing and fitting are essential for maximizing effectiveness 1, 3
• Combine bracing with rehabilitation including strengthening exercises, flexibility improvements, and technique refinement 1, 2
• Regular assessment of brace positioning and structural integrity is crucial 1

Pitfalls

• Relying solely on bracing without appropriate rehabilitation 1
• False sense of security leading to premature return to activities 1
• Brace migration during activity reducing effectiveness 1, 3
• Expecting objective benefits to match subjective improvements reported by patients 1

In conclusion, while hinged knee braces offer support for specific knee conditions, they should be considered as adjuncts to comprehensive rehabilitation rather than standalone treatments. The evidence for their effectiveness is stronger for certain indications (post-ACL support, MCL protection) than others.