AO Spine Thoracolumbar Injury Classification

AOSpine Thoracolumbar Classification (2013) + TL AOSIS (2016)

Classifies thoracolumbar spine injuries into morphology types A0–A4, B1–B3 and C together with neurologic status (N0–N4/NX) and the M1/M2 modifiers, and derives the Thoracolumbar AOSpine Injury Score (TL AOSIS) that feeds the published surgical algorithm.

Also searched as: trauma · fracture · aospine · spine fracture · burst

Primary injury morphology

If a type B or C pattern coexists with a vertebral body fracture, classify the body fracture separately and report the most severe pattern as primary.

Secondary (multilevel) injury morphology

Neurologic status

Ongoing spinal cord compression ("+" modifier)

Continued neural compression on imaging in a patient with a neurologic deficit.

M1 — Indeterminate posterior tension-band injury

Imaging (with or without MRI) cannot confirm or exclude posterior ligamentous complex injury in an otherwise type A pattern.

M2 — Patient-specific comorbidity

e.g. ankylosing spondylitis, DISH, osteoporosis, overlying burns, polytrauma. Unscored; may shift the treatment threshold either way.

Information

Incomplete input

Please provide: Primary injury morphology (A0–A4, B1–B3, or C).

How this tool works

The AOSpine thoracolumbar system (Vaccaro et al., 2013) grades fracture morphology hierarchically: type A injuries are axial-compression patterns (A0 minor nonstructural through A4 complete burst), type B injuries disrupt either the posterior or anterior tension band, and type C injuries show displacement or translation in any plane. The morphologic grade is combined with the patient’s neurologic status — N0 intact to N4 complete cord injury, NX when examination is impossible, with a "+" suffix for ongoing cord compression — and two case-specific modifiers: M1 for an indeterminate posterior tension-band injury and M2 for comorbidities that may argue for or against surgery. The companion TL AOSIS score (Kepler et al., 2016) assigns points to each element; totals of 0–3 favor nonoperative care, 4–5 are indeterminate, and 6 or more favor operative stabilization (Vaccaro et al., surgical algorithm, 2016).

References

Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.

Clinical questions that use this

Vetting guides that reach for this tool.

Related calculators

Same subspecialty, overlapping subject matter.

TLICS — Thoracolumbar Injury Classification & Severity Score SLICS — Subaxial Injury Classification & Severity Score