What Are Focal Tenderness and Step-Off Deformity?
Focal tenderness is point tenderness localized to the spinous process of a fractured vertebra, while step-off deformity is a palpable discontinuity or abrupt change in the alignment of adjacent spinous processes, indicating posterior column disruption or severe vertebral collapse.
Focal Tenderness
Clinical Significance:
- Point tenderness at the spinous process of the fractured vertebra is a classic physical examination finding in vertebral compression fractures 1
- This represents localized pain elicited by direct palpation or percussion over the affected vertebral level 1
- Focal tenderness helps identify the specific painful vertebral level, particularly important when multiple compression deformities are present on imaging 2
Examination Technique:
- Systematic palpation along the midline spine, applying pressure to each spinous process sequentially 1
- Percussion at the suspected fracture site can also elicit focal pain 3
- The thoracolumbar junction (T12-L1) is especially at risk for sustaining vertebral compression fractures and warrants careful examination 3
Step-Off Deformity
Clinical Significance:
- A palpable step-off represents an abrupt change in the normal smooth contour of the spinous processes 4
- This finding suggests more severe injury involving the posterior column, potential instability, or significant vertebral body collapse 4
- In pediatric spine trauma, the absence of midline tenderness (which would include step-off deformity) is one of the NEXUS low-risk criteria, though its relevance as a predictor of cervical injury in children has been questioned 4
Examination Technique:
- Run fingers along the spinous processes from superior to inferior, feeling for any discontinuity in alignment 4
- A step-off may indicate posterior ligamentous disruption or fracture-dislocation 4
Critical Clinical Context
When These Findings Matter Most:
- A complete lower extremity neurological examination is essential when focal tenderness or step-off deformity is present, including motor strength, sensation, reflexes, and rectal tone 1
- These physical findings help localize the level requiring imaging attention 1, 3
- In trauma patients, these examination findings combined with mechanism of injury guide imaging decisions 5
Important Caveats:
- Physical examination findings are often normal in vertebral compression fractures, with more than two-thirds of patients being asymptomatic and diagnosed incidentally on imaging 6
- In patients meeting high-risk criteria (age ≥60 years, high-risk mechanism, severe back pain), do not rely solely on physical examination 5
- Altered mental status, intoxication, or distracting painful injuries can mask these physical findings, necessitating imaging clearance regardless of examination 5
- The presence of focal tenderness without step-off deformity is more common and typically indicates an isolated vertebral body compression fracture without posterior column involvement 1, 6