Complete vs Incomplete Spinal Cord Injury Explained

Early in a spinal cord injury, two words decide most of what follows: complete or incomplete. They come from a neurologic exam, they get written into the chart in a shorthand most people are never taught to read, and they shape both the medical outlook and the case.

The distinction

A complete injury means no motor or sensory function is preserved below the level of injury, including the lowest sacral segments. An incomplete injury means some function remains below that level, even if it is limited. That preserved function is why incomplete injuries carry a broader range of outcomes.

It is worth being clear about what these words do not mean. "Complete" does not mean the cord was severed, and it does not mean nothing will ever change. It is a description of function at the time of examination, and examinations are repeated for exactly that reason. Most spinal cord injuries do not cut through the cord at all; the damage usually comes from bone fragments tearing into cord tissue or pressing on it.^[2]

How it is measured

Clinicians use the ASIA Impairment Scale, from the American Spinal Injury Association, graded A through E. The full neurologic exam behind it, which tests muscle strength and the ability to feel light touch and a pinprick, is typically done around the third day after the injury.^[1]

• A, complete. No motor or sensory function below the level of injury.
• B, sensory incomplete. Sensation, but not movement, is preserved below the neurologic level, including some sensation in the lowest sacral segments, S4 and S5.
• C, motor incomplete. Some movement is preserved below the level, but more than half of the key muscles below it cannot move against gravity (a muscle grade below 3).
• D, motor incomplete. At least half of the key muscles below the level can move against gravity (grade 3 or more).
• E, normal. Motor and sensory function test normal.

That sacral detail is why the exam is thorough in places people do not expect. Whether any sensation survives at S4 and S5 is what separates an A from a B, and that one finding moves the injury from complete to incomplete.^[1]

The grade is assigned alongside a level, the lowest segment with normal function. Together, level and grade are the shorthand that predicts most of the medical arc. Older charts might say "C4 quadriplegic"; a current chart is more likely to read "C4 ASIA A tetraplegia," which tells you both where the injury is and how much function remains below it.^[1]

Why the level matters as much as the grade

• Cervical (C1 to C8). Affects arms and hands, and the highest injuries affect breathing. Hand function is often the dividing line for independent living.
• Thoracic (T1 to T12). Upper limbs generally spared. Trunk stability and independent transfers vary with the level.
• Lumbar and sacral. Increasing preserved leg function, with bowel, bladder, and sexual function commonly affected.

Two people can both be graded ASIA A and live very different lives, because the level differs. This is why a classification alone is not a valuation.

The part that matters for a claim

Early classification is done under difficult conditions, sometimes while a person is sedated, intubated, or in spinal shock, and it is frequently revised over the following weeks. That revision is medically ordinary. In a claim it becomes important, because an early note and a later assessment that disagree will be noticed, and the gap generally gets read against the injured person unless somebody puts the sequence in order and explains it.

Reading the rehabilitation records closely matters more here than reading the acute chart. The acute record captures a crisis. The rehabilitation record captures function, and function is what the case is actually about.

Recovery, honestly

Incomplete injuries can improve, sometimes considerably, and most meaningful neurologic change happens in the first year, though it does not stop precisely at twelve months. Complete injuries improve less often. The practical consequence is the same in both cases: the picture used to value the case should be the plateau, not the first month.

Questions people ask a Denver spinal cord injury lawyer

When should I talk to a spinal cord injury attorney in Denver?

Earlier than most people think, and usually well before the medical picture settles. Nothing about the case needs to be valued in the first months, but evidence about how the injury happened, which insurance policies exist, and what the early neurologic exams recorded is easiest to secure at the start. Valuation can wait for the plateau. Preservation cannot.

How long do I have to file a spinal cord injury claim in Colorado?

It depends on how the injury happened. Most tort claims, including negligence claims for falls, unsafe property, and similar injuries, must be filed within two years.^[3] A claim for bodily injury arising from the use or operation of a motor vehicle generally has three years.^[3] The clock generally starts when both the injury and its cause are known or should have been known with reasonable diligence.^[3] Claims against a government body involve a much shorter notice deadline. Our guide to the Colorado personal injury statute of limitations walks through the exceptions.

What does a lawyer actually do with the ASIA records?

Puts them in order. We line up each exam, the grade and level it recorded, and the conditions it was done under, then match that sequence to the rehabilitation notes and the treating physicians' opinions. A classification that improved from A to B, or from C to D, is not a weakness in the case. It is the medical record working as intended, and it needs to be explained that way before an insurer explains it differently.

Does a complete injury always mean a larger claim than an incomplete one?

No. The level, the person's age and work, the care actually needed, and the available insurance all matter, and an incomplete cervical injury can involve more care than a complete low-lumbar one. We explain the factors in what drives the value of a Colorado spinal cord injury claim.

What to do with this

Ask for the ASIA grade and level in writing, and ask again after each reassessment. Keep the rehabilitation notes, not just the hospital discharge summary. If the classification in the chart does not match the function you actually have, that is worth having somebody look at, because it flows straight through to the life care plan and from there to the value of the case.

We represent injured people in Denver and across Colorado and are available to evaluate spinal cord injury claims. No attorney fee unless we recover for you, and we do not charge case costs if we do not win. If you want someone to read the records with you, call (720) 432-7032 or reach our Denver spinal cord injury lawyers. Related: how lifetime care costs are calculated.

Article Sources

1. Eunice Kennedy Shriver National Institute of Child Health and Human Development (NIH), "How is SCI diagnosed?". Neurologic exam on about the third day after injury; ASIA Impairment Scale grades A through E, including S4–S5 sacral sensation for grade B and the muscle-grade-3 threshold between C and D. https://www.nichd.nih.gov/health/topics/spinalinjury/conditioninfo/diagnosed. Accessed October 31, 2026.
2. MedlinePlus, National Library of Medicine, "Spinal Cord Injuries". "Most injuries don't cut through your spinal cord"; complete versus incomplete injury defined by function below the level. https://medlineplus.gov/spinalcordinjuries.html. Accessed October 31, 2026.
3. Colorado Revised Statutes 2024, Title 13 (C.R.S. §§ 13-80-101(1)(n), 13-80-102(1)(a), 13-80-108(1)). Three-year limit for motor-vehicle bodily-injury torts; two-year limit for other tort actions; accrual when the injury and its cause are known or should have been known. https://content.leg.colorado.gov/sites/default/files/images/olls/crs2024-title-13.pdf. Accessed October 31, 2026.