Neck pain from screen work: the tissue mechanics

The human head weighs approximately 5kg in neutral position. For every centimetre it migrates forward of that neutral position, the effective load on the cervical spine increases by approximately 4–5kg. A head 4–5cm forward of neutral, which is common in desk workers, adds 20–25kg of effective load to the structures supporting it.

This is not a posture problem. It is a load problem. Telling someone to sit up straight moves the head back temporarily. It does not address the thoracic stiffness and scapular control deficit that allow the head to migrate forward in the first place.

The suboccipitals are a group of small muscles at the base of the skull that control fine movements of the head. When the head is held in sustained forward position, the suboccipitals work constantly to prevent the head from dropping further. Over time, trigger points develop in these muscles, and the referral pattern from suboccipital trigger points runs up and over the skull to the eye and temple, mimicking tension headache and migraine.

Releasing suboccipital trigger points reduces headache frequency in many desk workers, not because the headaches were primary head problems, but because the cervical load driving them has been addressed.

The upper trapezius is not the primary problem in most neck pain cases. It is responding to thoracic stiffness that limits scapular mobility. When the thoracic spine cannot rotate and extend freely, the upper traps work harder to stabilise the shoulder girdle and hold the scapula in position. The traps are overloaded because the thorax is failing.

Releasing the upper traps without improving thoracic extension produces a session of relief and a week of return. Address the thorax, and the trap tension reduces because the demand has changed.

The deep neck flexors (longus colli, longus capitis) are the muscles that stabilise the cervical spine from the front. In most chronic neck pain cases, they are inhibited, the cervical extensors are overworking and the flexors are not doing their share. Deep neck flexor activation exercises (chin tucks, head lifts performed slowly in supine) rebalance this and reduce the sustained extensor load.

A screen positioned below eye level increases cervical flexion load. A screen too far away increases forward head position. Both are load problems, not aesthetic problems. Screen height at eye level and arm's length distance reduce the forward head migration significantly. These are structural changes, not reminders to sit up straight.