Which statement describes the extensor synergy pattern for the lower extremity?

Which statement describes the extensor synergy pattern for the lower extremity?

• A. Hip: extension, adduction, internal rotation; Knee: extension; Ankle: plantarflexion; Toes: flexion
• B. Hip: flexion, abduction, external rotation; Knee: flexion; Ankle: dorsiflexion and inversion; Toes: extension
• C. Hip: extension, abduction, external rotation; Knee: flexion; Ankle: dorsiflexion; Toes: extension
• D. Hip: flexion, adduction, internal rotation; Knee: extension; Ankle: plantarflexion; Toes: extension

Answer: (A)

In the lower extremity extensor synergy, multiple joints move together toward extension after a CNS injury. The hip tends to extend, adduct, and internally rotate; the knee remains extended; the ankle plantarflexes; and the toes flex. This pattern reflects coactivation of the extensor muscles and reduced ability to move joints independently. The statement that describes hip extension with adduction and internal rotation, knee extension, ankle plantarflexion, and toes flexion fits this pattern exactly, so it’s the best choice. Other options show hip flexion (instead of extension), different rotational positions, knee flexion, dorsiflexion, or toe extension—movements more characteristic of flexor synergy or non-synergistic patterns, not the extensor pattern described above.

In the lower extremity extensor synergy, multiple joints move together toward extension after a CNS injury. The hip tends to extend, adduct, and internally rotate; the knee remains extended; the ankle plantarflexes; and the toes flex. This pattern reflects coactivation of the extensor muscles and reduced ability to move joints independently.

The statement that describes hip extension with adduction and internal rotation, knee extension, ankle plantarflexion, and toes flexion fits this pattern exactly, so it’s the best choice.

Other options show hip flexion (instead of extension), different rotational positions, knee flexion, dorsiflexion, or toe extension—movements more characteristic of flexor synergy or non-synergistic patterns, not the extensor pattern described above.