Rotator Cuff Injury:
Why Can't I Lift My Arm?

The shoulder is one of the most mobile joints in the human body. Raising the arm, combing hair, dressing, reaching overhead — all require precise coordination between the shoulder joint and its surrounding muscles and tendons. When shoulder pain, weakness or restricted movement occurs, it is often attributed to "shoulder inflammation." However, rotator cuff injury is another important and frequently overlooked cause.

What Is the Rotator Cuff?

The rotator cuff is not a single muscle, but a functional collaboration of four muscles and their tendons:

Together these muscles keep the humeral head centred in the glenoid socket while enabling movement. They form a dynamic stabilisation system of the shoulder. Note: the teres major is adjacent but is not considered part of the rotator cuff anatomically.

How Do Rotator Cuff Injuries Occur?

Injuries typically arise from more than one cause. Acute injury — a fall onto an outstretched arm, sudden heavy lifting or a forceful sporting movement — can cause immediate damage. Degenerative change is equally important: with age, tendon structure changes and resilience decreases. Repetitive overhead activities (swimming, tennis, overhead work) add to the cumulative load.

Importantly, imaging studies show that rotator cuff tears can be present in people without significant shoulder pain. A finding of "tear" on MRI does not automatically mean all symptoms are caused by that tear.

Types of Rotator Cuff Injury

Conservative Treatment: The Core Approach

For many patients — particularly those with degenerative changes, partial tears or symptomatically stable full tears — conservative treatment is an important first approach. Prolonged complete immobilisation is counterproductive: it leads to muscle atrophy, loss of range of motion and harder rehabilitation later.

Treatment typically includes: activity modification (reducing pain-provoking movements while maintaining appropriate daily activity); pain management (medications, physiotherapy, selective injections where indicated); and rehabilitation — the most important element — focusing on gradual restoration of range of motion, scapular control, rotator cuff strength and overall shoulder coordination.

Acupuncture for Rotator Cuff Conditions

A 2024 meta-analysis of 13 randomised controlled trials (1,371 patients) found that acupuncture alone or combined with physiotherapy was associated with short- and medium-term improvements in pain, shoulder function and certain ranges of motion in rotator cuff conditions. [5]

In TCM, the treatment is not simply "needle where it hurts." Point selection follows meridian pattern diagnosis based on pain location, restricted movement direction and individual presentation — rather than primarily organ-based diagnosis, which plays a smaller role in local musculoskeletal conditions.

TCM and Modern Rehabilitation Work Together

Modern medicine answers: What has structurally happened to the tendon? Rehabilitation medicine asks: What can the shoulder currently do, and how can function be gradually restored? TCM focuses on: How can this individual's pain and movement restriction be addressed given their specific presentation?

These perspectives are complementary. For many patients, the key question is not "TCM or Western medicine?" but rather: which combination of treatments is appropriate at each stage of recovery?

When to Seek Medical Evaluation

Prompt assessment is important if you experience:

• Sudden severe shoulder pain after a fall or injury
• Sudden inability or significant difficulty raising the arm
• Marked loss of shoulder strength
• Progressively worsening night pain
• No improvement after a reasonable period of conservative treatment
• Known rotator cuff tear with increasing pain or weakness