Which statement about assigning a motor level for spina bifida is true?

Which statement about assigning a motor level for spina bifida is true?

• A. The motor level is the lowest intact functional neuromuscular segment
• B. The motor level is the most impaired side
• C. The motor level is determined by imaging only
• D. The motor level is the highest spinal segment with any movement

Answer: (A)

When assigning a motor level in spina bifida, focus on where voluntary movement still exists along the spine. The motor level is the lowest intact functional neuromuscular segment—the most caudal spinal segment that can still produce antigravity movement. Everything below that point is nonfunctional because the neural deficit prevents movement. This determination comes from a clinical motor exam, testing key muscles for movement against gravity and grading their strength, rather than from imaging alone. It isn’t about which side is more impaired, and it isn’t the highest segment that shows any movement. For example, if hip flexion (lower up the chain) is present but knee extension is absent, the motor level is at the lowest segment that still has functional movement, with lower segments being nonfunctional.

When assigning a motor level in spina bifida, focus on where voluntary movement still exists along the spine. The motor level is the lowest intact functional neuromuscular segment—the most caudal spinal segment that can still produce antigravity movement. Everything below that point is nonfunctional because the neural deficit prevents movement. This determination comes from a clinical motor exam, testing key muscles for movement against gravity and grading their strength, rather than from imaging alone. It isn’t about which side is more impaired, and it isn’t the highest segment that shows any movement. For example, if hip flexion (lower up the chain) is present but knee extension is absent, the motor level is at the lowest segment that still has functional movement, with lower segments being nonfunctional.