A morphometric study of the thoracolumbar spine spinous process and lamina space in the Chinese

The aim of the study was to analyse the anatomical parameters of the thoracolumbar spine spinous process and lamina space for Chinese anatomic study, and provide an anatomical reference for its clinical operation.

Samples from 24 adult autopsy subjects were obtained from the thoracolumbar spine spinous process and lamina space at levels T1 through L5. Direct measurements were made for the spinous process spacing distance, spinous process length, width, thickness and inclination angle, and the lamina space width and height.

1. Distance of the spine spinous process spacing: Thoracic part: The maximum tip distance was observed at T4~T5 level, and the minimum tip distance was observed at T9~T10 level. The maximum centre distance and root distance were observed at T11~T12 level, and the minimum were observed at T5~T6 level separately. Lumbar part: distance of spinous process spacing in lumbar part showed a decreasing pattern from L1~L2 to L5~S1. 2. Length, width, thickness of the spine spinous process: 1) The length of the spinous process: The upper border gradually increased from T1 to T6 and then decreased till T12 region. The centre region is T8 maximum, T11 minimum. The lower border length showed a decreasing trend from T1 to T12. Lumbar part: The length increased from L1 and reached maximum value at L3. Then, the length decreased gradually to reach minimum value at L5. 2) The width of the spinous process: The width showed an increasing trend from T1 to T12. Lumbar part: Maximum width was seen at L3 and a minimum L5. 3) The thickness of the spinous process: Tip thickness > Centre thickness > Root thickness in each thoracic and lumbar vertebra. Thoracic part: the maximum tip thickness is T1, T7 minimum, The maximum centre thickness is T12, T7 minimum. The maximum root height is T6, T9 minimum. Lumbar part: Maximum tip thickness was seen at L1, and a minimum L3. Maximum centre thickness was seen at L5, and a minimum L2. Maximum root thickness was seen at L2, and a minimum L1. 3. Inclination angle of the spine spinous process: The inclination angle gradually decreased from T1 to T7 to minimum value at T7 and then increased till T12 region. 4. Width and height of lamina space: 1) The width of lamina space: For thoracic part, the data became shorter gradually from T1~T2 to T5~T6, and then increased till to T11~T12. For lumbar part, the width of lamina space increased from T12~L1 to L5~S1. 2) The height of lamina space: In the thoracic vertebrae, the maximum height of centre region was observed at T11~T12 and the minimum mean value was observed at T3~T4. In the lumbar vertebrae, the height of the lamina space was gradually increased from T12~L1 to L5~S1.

This study reports morphometric data of the thoracolumbar spine spinous process and lamina space in the Chinese population, which provides an anatomic basis for thoracolumbar spine design of internal fixation, posterior surgery, puncture and epidural anaesthesia.