What is arm weakness?

Arm weakness refers to a loss of strength in the arm and the inability to move an arm because of decreased muscle strength. It can happen spontaneously or progress slowly over time. Weakness in the arm may occur on one or both sides of the body, may accompany weakness in other parts of the body, and may occur with a variety other symptoms, including arm pain. If you have arm weakness, you may have difficulty simply moving the affected arm, or you may have difficulty performing daily tasks.

In some cases, physical therapy may help to improve arm strength. If arm weakness occurs with pain, pain medication may assist in resolving both symptoms. Optimal treatment for arm weakness is dependent on the underlying cause of the weakness.

Usual causes of arm weakness include injury to, or infection of, the arm; muscle wasting, such as from certain muscular disorders or from lack of use; nerve damage or compression at the vertebral column; or certain hereditary conditions. Stroke is a serious and potentially life-threatening cause of sudden arm weakness that appears on one side of the body – a true medical emergency. Temporary arm weakness may be caused by a general infection, such as the common cold.

While arm weakness is generally not serious, arm weakness can be a sign of stroke. Seek immediate medical care (call 911) if you experience serious symptoms that may indicate a stroke, such as a sudden, severe headache; loss of consciousness; confusion; sudden numbness or paralysis, especially if it occurs on one side of the body; vision changes, or difficulty speaking.

If your arm weakness is persistent or causes you concern, seek prompt medical care.


What other symptoms might occur with arm weakness?

Arm weakness may accompany other symptoms, which vary depending on the underlying disease, disorder or condition.

Musculoskeletal symptoms that may occur along with arm weakness

Arm weakness may accompany other symptoms affecting the musculoskeletal system including:


What causes arm weakness?

Arm weakness can arise from a variety of events or disorders that affect the muscles, bones, joints, nervous system, or metabolism. Arm weakness can be accompanied by more generalized weakness, such as is common with certain hereditary disorders, or it may be the result of a specific injury to the arm.

Musculoskeletal causes of arm weakness

Arm weakness may be caused by... Read more about arm weaknesscauses

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Aug 9, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Bones, Joints and Muscles

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