Shoulder injuries after a crash — the mechanism is specific.

In the fraction of a second before impact, most people brace — an arm goes out to the wheel or the dash, the grip tightens, and the shoulder muscles fire. At impact the seatbelt locks across that same shoulder and the body is thrown forward against it. Two forces meet at one joint: the belt restraint from the front and the braced arm from below.

That is the seatbelt-shoulder pattern. The belt does its job — it keeps you in the seat — but the diagonal strap concentrates load across the front and top of the shoulder. The result is rarely one clean injury. It is often a cuff strain, an AC joint sprain, or a labral irritation, and sometimes more than one together. Pain frequently builds over the first day or two rather than arriving all at once.

Most crash shoulder injuries are soft-tissue and settle with rehab. A few need a doctor first. Standard shoulder X-rays are the appropriate first image after acute trauma, and MRI is added only when specific findings warrant it — the ACR Appropriateness Criteria for traumatic shoulder pain set out that sequence, and AAFP guidance on MRI use cautions against MRI as a routine screen for chronic shoulder pain.

• A shoulder that looks deformed, sits low, or you cannot move at all — possible dislocation or fracture.
• Sudden, profound weakness lifting or rotating the arm — possible full-thickness cuff tear.
• Numbness, pins and needles, or weakness running down the arm into the hand.
• A visible step or bump over the top of the shoulder after impact.
• Pain that is severe and unrelenting, or that wakes you and is not easing over days.

If any of those are present, that is a same-day call to your physician or to Lions Gate Hospital, not a physio booking. We screen for these at the first assessment and refer on when the picture calls for it.

The first visit is one part screening and one part planning. The physiotherapist clears the red flags above, checks active and passive range, tests the rotator cuff and the AC joint, and works out which tissue is driving the pain. Only then does a plan get set.

For a typical cuff strain or seatbelt contusion in the first two weeks, that means pain-free range-of-motion work, early scapular control, isometric cuff activation that the joint will tolerate, and a graded return to reaching and overhead tasks. Manual therapy and modalities can ease the first few weeks, but they are adjuncts — the endpoint is a shoulder that holds load through full range. Where there is a higher-grade AC sprain or a suspected labral injury, the early plan is more protective and the progression is slower.

Timelines depend on which structure is injured, how irritable it is, your baseline activity, and how early rehab starts. A soft-tissue strain without a full tear usually settles faster than a higher-grade AC separation or a labral injury. Your physiotherapist sets expectations after the first assessment rather than from a fixed number — and a flare-up along the way is information used to adjust load, not a setback.

Physiotherapy for a crash-related shoulder injury is covered under ICBC on an open claim, and you can generally start within the early funded window without a doctor's referral. Bring your claim number to the first visit and we handle the billing. For current session details and to book, see our Jane App booking page. If you were discharged from Lions Gate Hospital with a referral after the crash, bring that paperwork too.

This article is educational and is not a substitute for assessment by a regulated practitioner. It does not diagnose your injury. If you are seeing red flags — deformity, profound weakness, numbness down the arm, or severe unrelenting pain — seek medical assessment promptly rather than waiting for a physio appointment.