The headache that starts at the base of the skull.

The headache that readers describe after a crash has a particular shape. It begins low, at the junction of the skull and the neck, often on one side. It creeps up the back of the head and sometimes forward toward the temple or behind the eye. It gets worse when the neck has been held still for a long time, at a desk or behind a wheel, or when the head is turned. Readers usually ask the desk the same question: is this my neck, or is this my head? The honest answer is that it can be either, and it can be both, and an examination is how the question gets settled.

Where the neck and the head meet

The upper cervical spine is unusual. The top two vertebrae are shaped differently from the five below them, and a dense set of small muscles runs from those bones to the base of the skull. Those muscles and the joints they move are heavily supplied with nerves, and pain arising there is commonly felt in the head rather than in the neck. This is the general mechanism behind what clinicians call cervicogenic headache, a headache whose source is the neck. The NINDS description of whiplash lists headache among the symptoms that can follow the injury, which is why this desk treats the two as one story rather than two.

What the pattern usually looks like

The features that tend to point toward the neck are modest and consistent. One-sided, though it may switch sides. Starts at the back and moves forward. Provoked by neck position or movement. Accompanied by reduced range of motion and tenderness at the top of the neck. Often shows up on the same one to three day schedule as the rest of the neck strain described in Entry 03. None of these features is a test, and the desk is not inviting readers to diagnose themselves. They are the vocabulary a reader can use on the phone and in the exam room so that the clinician hears a clear description.

The bright line, drawn darkly

Some headaches after a crash are not about the neck at all, and they do not wait for an appointment. A headache that arrives suddenly and is the worst you have had. A headache with repeated vomiting. A headache with confusion that is getting worse, with trouble speaking, with weakness or numbness on one side, or with a seizure. Those are signs that the head, not the neck, needs immediate attention, and the right door is an emergency room. The CDC's HEADS UP material on concussion describes the danger signs in plain language and is worth reading before you need it.

When the head was struck

If your head hit anything in the crash, the headrest, the window, the steering wheel, or if you felt dazed or lost a moment of time, say so when you call the clinic and again in the room. Missouri Injury Clinic publishes TBI and concussion rehab as a lane next to auto injuries, naming tools such as oculomotor rehabilitation, neurofeedback, cognitive rehabilitation, and vagus nerve stimulation. The point of mentioning it here is narrow: a clinic that publishes that lane is a clinic that expects to be told about head symptoms, and you should not edit them out of your account because the appointment was "for the neck." Entry 05 takes that overlap seriously.

What an exam can do that a webpage cannot

A clinician can press on the specific joints and muscles at the top of the neck and see whether doing so reproduces the headache. They can measure how far the neck turns and in which directions it is limited. They can ask the questions that separate a neck-driven headache from one that needs imaging or a different specialty, and they can write all of it down with a date. That record is the baseline for everything after; it is also, if it ever matters, the dated document everyone will ask for. A reading desk can describe the pattern. It cannot put a hand on the structure.

The desk's position is the same as on every other entry: if the headache fits the emergency pattern, go to an ER now. If it fits the neck pattern, get examined this week, and describe it precisely. Either way, do not let it become a private experience you manage with the kitchen cabinet while the neck waits.

General information about headache after neck injury is consistent with NINDS and CDC material. This entry is educational, not medical advice, and cannot tell you what is causing your headache.