Whiplash after a crash: what it is, and how it gets treated

In a collision your car changes speed far faster than your head can. The torso is held by the seat and the belt, the head keeps travelling for a fraction of a second longer, and the neck is left to absorb the difference. The result is a rapid whipping motion through the cervical spine, most often in a rear-end impact, though side impacts and knocks at surprisingly modest speeds do it too. Load passes through the small facet joints at the back of the neck, through the discs, through the ligaments that hold the vertebrae in line, and through the deep muscles whose job is to stabilise your head.

Nothing about that requires a dramatic crash or a wrecked car. Vehicle damage is a poor predictor of neck injury, because a stiff, well-engineered body shell transmits more of the energy through to the occupants rather than absorbing it. Whether your head was turned at the moment of impact, whether you saw it coming and braced, your seat and headrest position, and your own neck before the crash all change the outcome more than the panel damage does.

The delay people find so confusing has a plain explanation. Adrenaline at the scene suppresses pain. The inflammatory response and the protective muscle spasm that follow a strain take hours to develop and often peak on the second or third day. Feeling fine at the roadside and stiff on Sunday morning is the ordinary course of this injury, not a sign that something new has happened.

The consultation starts with the collision itself. Direction of impact, whether you were stationary, seat and headrest position, head position, restraint use, airbag deployment, whether you got out unaided and what you felt in the first hour. That history is not small talk. It is the part that ties your neck to the crash, and it is the part nobody can reconstruct accurately six months later.

The examination follows: measured range of movement in each direction rather than a note saying restricted, palpation of the cervical and upper thoracic segments, muscle tone and tenderness patterns, and a neurological screen of the upper limbs covering power, reflexes and sensation. Where the history or the examination raises a concern, imaging is arranged. Where it does not, we say so in the notes, which is itself useful evidence.

That first appointment is also where the first Certificate of Fitness comes from. On a CTP claim only a treating medical practitioner may write it, which is one good reason to see a doctor before you see anybody else. What it records is what you can and cannot safely do, drawn from the examination rather than from a conversation about how the week has been.

Source: SIRA, Motor Accident Guidelines 4.68; Motor Accident Injuries Act 2017 s 3.15. Checked September 2026.

Section 1.6 of the Act splits motor accident injuries into threshold and non-threshold, and an ordinary neck strain sits squarely inside the threshold half. What moves a whiplash file out of it is narrower than most people assume. Nerve tissue is excluded from the soft tissue definition, but the Regulation then returns an injury to a spinal nerve root to the threshold category where it manifests in neurological signs other than radiculopathy. Arm symptoms are therefore not by themselves the answer. Radiculopathy is the finding that carries weight, alongside a complete or partial rupture of a ligament, which the definition excludes outright. The full statutory list of tissues and exclusions sits in section 6 of our NSW car accident injury guide.

The consequence is a date on a calendar. Land inside the threshold category and both halves of your support are capped at the one-year mark: 52 weeks of weekly payments under section 3.11, 52 weeks of funded treatment and care under section 3.28. Anyone who was wholly or mostly at fault is capped at the same point. Land outside it, without having been mostly at fault, and the picture changes materially. Weekly payments extend to 104 weeks, and treatment and care carry on for as long as they stay reasonable and necessary.

Here is the part that should change what you do this month. The insurer does not have to tell you whether it accepts liability for benefits after the first 52 weeks until nine months in, under section 6.19(2). By then the clinical record of your first eight weeks is fixed and unamendable. A nerve finding recorded in week two is evidence. The same finding recalled in month nine is a recollection. This is the reason our doctors measure and write things down that a routine appointment might not bother with.

The same logic applies to the psychological side. A psychological or psychiatric injury that is not a recognised psychiatric illness is a threshold injury, and the Regulation includes acute stress disorder and adjustment disorder in that category. Whether a person’s presentation meets a diagnosis is again a clinical question answered by contemporaneous records.

Source: Motor Accident Injuries Act 2017 ss 1.6, 3.11, 3.28 and 6.19; SIRA, Providing allied health services in the NSW CTP schemes — FAQs. Checked September 2026.

Ring us or use the booking page. Bring, or have to hand, the date of the crash, the police event number if you have it, the registration of the other vehicle, and the claim or reference number if the insurer has already given you one. If you have not lodged anything yet, say so on the call. The scheme allows a limited amount of early care in the month after a crash, before any claim exists, and it is easier to arrange when somebody asks the insurer for it on your behalf.

You choose who treats you. Under clause 4.104 the insurer has to act on a stated preference: name the provider you want and it is to arrange that referral, so long as the provider is suitable, and put its reasons in writing if it will not. Clause 4.99 goes a step further and allows a medical practice, rather than one named individual, to be nominated for the recovery plan. You are not obliged to take whoever an insurer suggests.

One honest caveat, because it is your money at stake. SIRA states plainly that an account for treatment the insurer has refused, or given on a claim where liability has been denied, falls back on the patient. So we confirm approval before booking a block of treatment, and we tell you where the claim stands rather than assuming you know. The mechanics of that sit on our treatment approvals page, and the first-week sequence is on our first 72 hours guide.

Source: SIRA, Motor Accident Guidelines 4.78–4.79, 4.99 and 4.104; SIRA, Fees paid for motor crash health services (updated 18 September 2025). Checked September 2026.