What Are Common Causes of Numbness and Weakness?

Numbness and weakness often go together, and they can be caused by many different things. Identifying a specific reason can be tricky without a comprehensive medical diagnosis, and a lot also depends on where, exactly, the symptoms are manifesting. One of the most common causes of temporary or sporadic weakness and numbness is nerve pinching or damage, which itself can be caused by a number of different things; everything from a problem with bone placement or spinal column anatomy to an awkward posture or uncomfortable sitting position. Injury is another common cause. More intensive symptoms may have a degenerative condition like Multiple Sclerosis to blame, and the paired problems can be caused by diabetes and hormonal imbalances, too. When the symptoms are limited to the hands and wrists, carpal tunnel syndrome is a common explanation. In general, anyone who is concerned about the tingles, weakness, or numbness they feel should get the opinion of a qualified medical provider to get a personalized diagnosis.

Weakness is usually defined as a reduction in the strength of one or more muscles. Numbness is an unusual sensation or, more accurately, the lack of sensation, in a particular part of the body. Both can be limited to particular parts of the body or more generalized, and they can be either fleeting or long-lasting. Sometimes, the explanation is simple; many people find that they have a pins-and-needles sensation and temporary weakness when they’ve crossed their legs for too long, or when they have been putting stress on a certain muscle groups. This will usually go away all on its own with restored circulation, and isn’t usually anything to be worried about. When numbness and weakness last for a significant length of time, however, whether individually or together, it could be the result of a medical condition that requires treatment.

Nerve problems are one of the most common causes of numbness, and weakness often follows along in many cases. A pinched nerve happens when nerves are damaged or injured by compression, constriction, or pressure. Numbness and weakness resulting from pinched nerves tend to be localized to the area in which the nerves are damaged. Sometimes medication can successfully alleviate the symptoms, but in others surgery is needed to free the nerve and restore feelings and motion.

Panic attacks — the sudden onset of extreme fear, anxiety or panic — can in some cases be extreme enough to cause physical symptoms. The weakness associated with a panic attack is in the legs and sometimes is referred to as “jelly legs.” Numbness can occur in the hands and feet when a person suffering from a panic attack hyperventilates.

Nerve and tissue damage owing to accidents or injury are also common explanations. In these cases, a person’s nerve receptors have usually been skewed or damaged to the point where they are registering signals and synapse fires either erroneously or not in proportion with their true strength. People recovering from serious injuries often experience a period of weakness and numbness that will subside as tissues heal, but physical therapy is often required to regain full strength — and some lasting symptoms may never fully disappear.

A number of degenerative conditions can also impact nerve function and sensation, perhaps none as profoundly as Multiple Sclerosis. Multiple Sclerosis is the result of a damaged myelin sheath, the part of cellular anatomy that blankets and protects nerve fibers. When the nerve fibers’ protectors are harmed, nerve impulses slow down or stop altogether. Nerve damage associated with multiple sclerosis is progressive, and those suffering from the disease can have symptoms that affect different parts of the body at different times.

One of the hallmarks of diabetes is an inability to produce enough insulin, a hormone made by the pancreas to control blood sugar. As an off-shoot of this insulin shortfall, people with diabetes have high blood sugar, which can lead to generalized weakness. When blood sugar levels are not consistently controlled, the result is often diabetic neuropathy, which can cause both localized weakness and numbness in the legs and arms. This is of particular concern because the numbness prevents diabetics from feeling pain in those areas, and they may not realize they have an injury that needs treatment until it's too late to repair.

Hypothyroidism, the result of a shortage of

, is related. This condition results in the body's metabolism slowing down. Associated weakness is usually generalized, while the numbness is typically localized to the hands and feet.

Carpal tunnel syndrome occurs when the median nerve in the wrist is compressed in an area known as the carpal tunnel. This can happen as the result of repetitive motion activities involving the wrists and hands. One of the most common culprits is computer use, particularly keyboarding and mousing. Carpal tunnel syndrome can cause pain, numbness and weakness severe enough to require surgery if less invasive treatments don't work.