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Spine
intermediate
X-Type

Adult Spinal Deformity - Sagittal Balance and Classification

Spinal Deformity

A 65-year-old woman presents with progressive back pain and difficulty standing upright. She bends her knees and hips to maintain balance. Standing full-spine radiographs show: C7 plumb line 8cm anterior to S1, lumbar lordosis 25 degrees, pelvic incidence 55 degrees, and pelvic tilt 32 degrees. Her functional scores are significantly impaired. Regarding adult spinal deformity:

Mark each as TRUE or FALSE

A

Pelvic incidence (PI) is a fixed anatomical parameter that cannot be changed surgically; lumbar lord...

B

The SRS-Schwab classification uses three sagittal modifiers: PI-LL mismatch (under 10°, 10-20°, over...

C

Pelvic incidence can be corrected surgically by lumbar osteotomies; decreased pelvic tilt indicates ...

D

Compensatory mechanisms for sagittal imbalance include pelvic retroversion (increased pelvic tilt), ...

E

Osteotomy options include SPO/Ponte (5-10 degrees per level, posterior only), PSO (30-40 degrees, th...

Answer the questions to see explanations

Click T (True) or F (False) for each option