Sagittal knee kinematics after rectus femoris transfer without hamstring lengthening

Area of Science:

• Orthopedics
• Pediatric Surgery
• Biomechanics

Background:

• Rectus femoris transfer is a surgical procedure used to correct crouch gait in children.
• Hamstring lengthening is often performed concurrently, but its necessity is debated.
• Understanding the impact on knee kinematics is crucial for surgical decision-making.

Purpose of the Study:

• To evaluate the sagittal knee kinematics after rectus femoris transfer without concomitant hamstring lengthening.
• To determine if the procedure affects knee flexion during different phases of gait.
• To compare findings with previous research on similar surgical interventions.

Main Methods:

• Retrospective review of seventeen children (29 knees) who underwent rectus femoris transfer.
• Gait analysis performed pre-operatively and at least one year post-operatively.
• Analysis focused on key sagittal knee kinematic parameters: stance minimum knee flexion, swing maximum knee flexion, and swing minimum knee flexion.

Main Results:

• A significant increase in stance minimum knee flexion (7 degrees) was observed.
• Swing minimum knee flexion also increased by 5 degrees.
• The study confirmed prior findings of increased swing maximum knee flexion (5 degrees).

Conclusions:

• Rectus femoris transfer alone, without hamstring lengthening, positively impacts sagittal knee kinematics in children.
• The procedure leads to improved knee flexion during both stance and swing phases of gait.
• These findings suggest that hamstring lengthening may not always be necessary in conjunction with rectus femoris transfer.