Arm Stiffness: Causes and When to Worry

What arm stiffness feels like

Stiffness can mean two different things, and the difference helps point to a cause:

• Joint stiffness: a joint will not move through its full range, whether you move it yourself or someone else moves it. Typical of frozen shoulder, arthritis and stiffness after an injury.
• Muscle tightness or rigidity: the joint can move, but the muscles resist or feel tight. Typical of overuse, muscle strain, cramps and nervous system problems such as Parkinson's disease or spasticity after a stroke.

Arm stiffness causes by location

Common causes

Frozen shoulder

Frozen shoulder (adhesive capsulitis) is a thickening and tightening of the shoulder joint capsule. It causes gradually worsening pain and then marked stiffness, especially when rotating the arm outward. It is most common between ages 40 and 60 and in people with diabetes or thyroid disease. It runs through freezing, frozen and thawing phases over 1 to 3 years.

Rotator cuff problems

Rotator cuff injuries, from tendinitis to tears, cause pain lifting the arm out to the side and overhead, night pain, and stiffness as people avoid moving the shoulder. Unlike frozen shoulder, someone else can often lift the arm higher than you can lift it yourself.

Arthritis

Shoulder arthritis and elbow arthritis cause gradual stiffness, grinding and pain. Rheumatoid arthritis causes warm, swollen joints with morning stiffness lasting an hour or more.

Muscle overuse and strain

Heavy lifting, new workouts, repetitive work and poor posture at a desk leave muscles sore and tight for 1 to 3 days (delayed-onset muscle soreness). Tight chest and neck muscles also contribute to a stiff upper arm.

After injury or immobilization

After a fracture, dislocation or surgery, or weeks in a sling or cast, joints stiffen quickly. Physical therapy is the main treatment.

Nerve and brain causes

• Pinched nerve in the neck: cervical radiculopathy causes pain, tingling, numbness and weakness running from the neck into the arm. Muscles may feel tight and guarded.
• Parkinson's disease: rigidity is a core feature of Parkinson's disease. The arm feels stiff and moves less when walking, often on one side first, with slowness and sometimes a resting tremor.
• Stroke: a stroke causes sudden weakness. Weeks later, the arm may become stiff and bent (spasticity).
• Polymyalgia rheumatica: polymyalgia rheumatica causes stiffness and aching in both shoulders and upper arms, worst in the morning, in people over 50. It responds quickly to steroids.
• Rare causes: dystonia, tetanus, stiff-person syndrome and some medicines (antipsychotics) can cause rigid muscles.

How doctors find the cause

A doctor will ask when the stiffness started, whether it is in one joint or the whole arm, about pain, injury, weakness, numbness, morning stiffness and other joints. They will compare active movement (you move it) with passive movement (they move it), test strength, reflexes and sensation, and look for tremor or slowness.

Tests may include X-rays for arthritis, ultrasound or MRI for rotator cuff tears, blood tests for inflammation (ESR, CRP), rheumatoid factor and thyroid, and nerve conduction studies or an MRI of the neck for nerve problems.

Treatment and home care

• Keep moving gently: pendulum swings, wall walks with your fingers and towel stretches behind the back help shoulder stiffness. Do them little and often, several times a day.
• Heat before exercise: a warm shower or heat pack for 15 minutes loosens tight muscles and joints. Ice afterward if it aches.
• Pain relief: acetaminophen (paracetamol) or ibuprofen, following the label, to allow movement.
• Posture breaks: at a desk, stand and roll your shoulders every 30 to 60 minutes.
• Physical therapy: a structured program is the main treatment for frozen shoulder, rotator cuff problems and stiffness after injury.
• Medical treatment: steroid injections for frozen shoulder or rotator cuff pain, steroids for polymyalgia rheumatica, arthritis medicines, Parkinson's medicines, and antispasticity treatments after stroke.
• Surgery: for large rotator cuff tears, severe arthritis, or frozen shoulder that does not improve with other treatments.

Frequently asked questions

Why does my arm feel stiff and tight?

Most often because of a shoulder problem, such as frozen shoulder or a rotator cuff injury, or tight, overworked muscles. A pinched nerve in the neck, arthritis and polymyalgia rheumatica are other causes. Stiffness on one side with slowness or tremor can be an early sign of Parkinson's disease.

What causes a stiff arm and shoulder without injury?

Frozen shoulder, rotator cuff tendinitis and arthritis are the usual causes. Frozen shoulder is more common in people with diabetes. In people over 50, stiffness in both shoulders in the morning may be polymyalgia rheumatica, which needs a blood test and prompt treatment.

Is arm stiffness a sign of a stroke?

Sudden weakness, numbness or clumsiness of one arm can be a stroke and needs emergency care. Stiffness itself usually develops weeks after a stroke as spasticity. Gradual stiffness over weeks or months is more often from joints, muscles or nerves.

How do I loosen a stiff arm?

Apply gentle heat, then move the arm slowly through its range: pendulum swings, wall finger walks and gentle stretches, several times a day. Avoid forcing painful movements. If stiffness persists beyond 2 to 3 weeks, see a doctor or physical therapist.