# Back and neck injuries after a car accident: discs, scans and old injuries

> Herniated discs and other back and neck injuries after a crash: what scans show, old wear versus new injury, the eggshell rule and medical exams.

Canonical page: https://accidentclaimfacts.com/injuries/back-and-neck-injuries/  
Last reviewed: October 29, 2026 by the Accident Claim Facts editorial team  
General information, not legal advice. Talk to a licensed attorney in your state.

## Quick answer

Crashes commonly cause back and neck sprains and strains, herniated discs and broken vertebrae. In many of these claims the hardest question is not whether you are hurt but whether the crash caused it, because age-related wear in the spine is common and shows up on scans. The law generally lets you claim for the harm the crash caused, including making an old condition worse, but not for the old condition itself. Insurers may test that line with their own medical exam.

## Key facts

| Fact | Detail | Note |
|---|---|---|
| People who have back pain at some point | 8 out of 10 people | MedlinePlus |
| When back pain is called chronic | When it lasts more than 3 months | MedlinePlus |
| Age-related neck changes | By age 60, most people show signs of cervical spondylosis on x-ray | MedlinePlus |
| After a court-ordered exam in a federal case | On request, a copy of the examiner's written report | Federal Rule of Civil Procedure 35 |
| The eggshell plaintiff rule in California | Full damages even if the injured person was more susceptible to injury than a normally healthy person would have been | Jury instruction CACI No. 3928 |

## Common back and neck injuries from crashes

MedlinePlus, the National Library of Medicine's health site, lists a sudden jolt such as a car accident among the causes of back injuries, and names the most common ones: sprains and strains, herniated disks, and fractured (broken) vertebrae. The lower back is the most common site of back injuries and back pain.

Sprains and strains are injuries to the muscles and ligaments that support the spine. MedlinePlus says sudden low back pain is most often caused by an injury to those tissues. In the neck, the best-known version is [whiplash](https://accidentclaimfacts.com/injuries/whiplash/).

### Herniated discs

The bones of the spine are separated by disks that cushion the spinal column and let it bend. According to MedlinePlus, a disk can move out of place (herniate) or break open (rupture) from injury or strain. When that happens, it can press on spinal nerves and cause pain, numbness or weakness.

The lower back is the most common place for a herniated disk, and the neck is second. MedlinePlus describes the typical pattern:

- **Lower back:** sharp pain in part of the leg, hip or buttocks, with numbness in other areas, sometimes reaching the calf or the sole of the foot.
- **Neck:** pain when moving the neck, deep pain near the shoulder blade, or pain that travels down the arm to the fingers, sometimes with numbness.

MedlinePlus notes that this pain often starts slowly, which is one reason a disk injury may not be found at the first visit after a crash.

### Broken vertebrae and nerve damage

A crash can also fracture the bones of the spine. NINDS notes that damage to the vertebrae around the spinal cord can injure the cord itself. Our guides to [broken bones](https://accidentclaimfacts.com/injuries/broken-bones/) and [spinal cord injury](https://accidentclaimfacts.com/injuries/spinal-cord-injury/) cover these.

> **Warning:** MedlinePlus advises contacting a provider for severe back pain that does not go away, or for any numbness, loss of movement, weakness, or bowel or bladder changes.

## What imaging can and cannot show

Scans are central to back and neck claims, but each test answers a different question. MedlinePlus explains the main ones:

| Test | What it is used for |
|---|---|
| X-ray | Checking the bones, including fractures and other causes of pain; it cannot diagnose a herniated disk on its own |
| MRI or CT scan | Showing where a herniated disk presses on the spinal canal |
| Electromyography (EMG) | Finding which spinal nerve root is affected |

An MRI can also show too much. MedlinePlus says an MRI of the spine can pick up most past injuries and changes that happen with aging, including small problems that are not the cause of current pain. A post-crash MRI report may therefore describe "degenerative" changes alongside a new injury, and an insurer may point to that wording.

Without an earlier scan, it can be hard to say which findings are new. If you had spine imaging before the crash, those images and reports let doctors compare. Our guide to [medical records for an injury claim](https://accidentclaimfacts.com/claim-process/medical-records/) explains how to get them.

## Old wear and tear versus a new injury

Changes in the spine are common with age. MedlinePlus says cervical spondylosis, wear on the disks and bones of the neck, is caused by aging and chronic wear, and that by age 60 most people show signs of cervical spondylosis on x-ray. Back pain affects 8 out of 10 people at some point in their lives. So many people who are hurt in a crash already have some history of back or neck trouble.

That history does not end a claim. A pre existing condition is treated differently from a new injury, but harm the crash caused to it still counts. California's jury instruction, for example, allows damages for the effect of the crash on a physical or emotional condition that it made worse, but not for the condition the person already had. The dispute is then about causation: how much of the current problem the crash caused.

The evidence that answers that question tends to come from:

- older records showing how you were before the crash, such as long periods without treatment, or symptoms that were mild and stable;
- the change after the crash: new symptoms, new locations of pain, or new findings such as numbness or weakness;
- your treating doctor's opinion on what the crash changed;
- consistent reporting at every visit, including about your history.

> **Example:** A 52-year-old with occasional stiffness in his lower back, and no treatment for it in three years, is rear-ended. Within days he has pain shooting down one leg. His MRI shows a herniated disk and age-related wear. His older records show the stiffness was mild and untreated, and his doctor explains which findings fit the new symptoms. The claim is for what the crash changed.

Being open about your history from the start can help. The other side will look for earlier records, and in a lawsuit they can be obtained through discovery. A history that comes out late can look worse than one disclosed at the start.

## The eggshell plaintiff rule

The eggshell plaintiff rule, also called the thin skull rule, is a long-standing principle of injury law. Cornell's Legal Information Institute describes it as holding a defendant liable for the full extent of a plaintiff's unusual reactions to the defendant's wrongful act: the defendant must "take the victim as they find them."

In practice, it means the at-fault driver cannot avoid paying because the injured person was more fragile than most. California's jury instruction tells jurors to decide the full amount of damages even if the injured person was more susceptible to injury than a normally healthy person would have been, and even if a healthy person would not have been hurt in the same way.

| Situation | What can usually be claimed |
|---|---|
| An old condition that the crash did not change | Nothing for that condition |
| An old condition that the crash made worse | The worsening, and its effects |
| A fragile person hurt worse than most people would be | The full harm the crash caused |

The details vary by state, and the line between the second and third rows is often argued over. A licensed attorney in your state can explain how courts there apply the rule.

## Independent medical examinations

An independent medical exam (IME) is an examination by a doctor chosen by the insurer or the other side in a lawsuit. Despite the name, the doctor is not your doctor and is not there to treat you; the report goes to the side that asked for it.

IMEs come up in two main ways:

1. **Under your own policy.** Your auto policy lists your duties after a crash. These can include being examined by a doctor the insurer chooses before it pays benefits such as personal injury protection. The "duties after an accident or loss" part of your policy sets out what yours requires.
2. **In a lawsuit.** In federal court, Rule 35 of the Federal Rules of Civil Procedure says a court may order a party whose mental or physical condition is in controversy to be examined, on motion for good cause. The order must specify the time, place, manner, conditions, and scope of the examination, and who will perform it. On request, the person examined is entitled to a copy of the examiner's written report. State courts have their own versions of this rule, and exams can also happen by agreement.

Many people bring a list of their symptoms and treatment to the exam, answer questions the same way they have at every visit, and write down afterward how long the exam lasted and what was done. When an IME report disagrees with your treating doctors, the disagreement becomes part of the negotiation and, in a lawsuit, part of the evidence each side presents. Our guide to [filing a lawsuit](https://accidentclaimfacts.com/claim-process/filing-a-lawsuit/) explains when exams and other discovery happen.

## FAQ

### Can a car accident cause a herniated disc?

Yes. MedlinePlus says a disk can move out of place or break open from injury or strain, and lists a sudden jolt such as a car accident among the causes of back injuries. The pain often starts slowly, so it may not be found at the first visit.

### What if my MRI shows degenerative changes?

That is common. MedlinePlus says an MRI can pick up changes that happen with aging, even ones not causing current pain. The claim then turns on what the crash changed, shown by older records, new symptoms and your doctor's opinion.

### Can I make a claim if I had back problems before the accident?

Generally, yes. You usually cannot claim for the old condition itself, but you can claim for the extent to which the crash made it worse, and for any new injury.

### What is the eggshell plaintiff rule?

It is the rule that the person who caused an injury is responsible for the full harm it did, even if the injured person was more fragile than average. The at-fault driver must take the injured person as they find them.

### Do I have to attend an independent medical exam?

It depends. Your own policy may require an exam before paying some benefits, and in a lawsuit a court can order one if your condition is in controversy and there is good cause. A licensed attorney in your state can tell you what applies to your claim.

### Can I get a copy of the IME report?

In federal cases, Rule 35 entitles the person examined to a copy of the examiner's written report on request. State court rules vary, so ask how it works where your claim is.

## Sources

- [MedlinePlus, Back injuries](https://medlineplus.gov/backinjuries.html) — common back injuries and causes
- [MedlinePlus, Herniated disk](https://medlineplus.gov/ency/article/000442.htm) — causes, symptoms and tests
- [MedlinePlus, Low back pain: acute](https://medlineplus.gov/ency/article/007425.htm) — injuries to muscles and ligaments
- [MedlinePlus, MRI and low back pain](https://medlineplus.gov/ency/article/007493.htm) — MRI findings from past injuries and aging
- [National Institute of Neurological Disorders and Stroke, Spinal Cord Injury](https://www.ninds.nih.gov/health-information/disorders/spinal-cord-injury) — damage to the vertebrae can injure the spinal cord
- [Cornell Legal Information Institute, Wex: eggshell skull rule](https://www.law.cornell.edu/wex/eggshell_skull_rule) — definition of the rule
- [MedlinePlus (National Library of Medicine), Back Pain](https://medlineplus.gov/backpain.html), checked October 29, 2026
- [MedlinePlus Medical Encyclopedia, Cervical spondylosis (review date 6/4/2025)](https://medlineplus.gov/ency/article/000436.htm), checked October 29, 2026
- [Cornell LII, Federal Rules of Civil Procedure, Rule 35. Physical and Mental Examinations](https://www.law.cornell.edu/rules/frcp/rule_35), checked October 29, 2026
- [Judicial Council of California, Civil Jury Instructions (CACI) 2026 edition, No. 3928](https://courts.ca.gov/system/files/file/judicial_council_of_california_civil_jury_instructions_2026.pdf), checked October 29, 2026