Weakness is 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. Numbness and weakness can both be generalized, or felt all over, or localized to a particular area of the body. When numbness and weakness last for a significant length of time, whether individually or together, it could be the result of a medical condition that requires treatment, such as multiple sclerosis, diabetes, or carpal tunnel syndrome.
Multiple sclerosis is the result of a damaged myelin sheath, the part of the body that blankets and protects nerve cells. When the nerve cells' protector is 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. The related numbness and weakness is localized, depending on what parts of the body are affected.
Diabetics don’t produce enough insulin, a hormone made by the pancreas to control blood sugar, and some type 1 diabetics produce no insulin at all. Type 2 diabetics either don’t produce enough insulin or their bodies are resistant to the insulin they do produce. 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 causes 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.
Panic attacks — the sudden onset of extreme fear, anxiety or panic — can 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.
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.
A pinched nerve happens when nerves are damaged or injured by compression, constriction or pressure. Numbness and weakness resulting from a pinched nerve are localized to the area in which the nerves are damaged. Hypothyroidism, the result of a shortage of thyroid hormones, results in the body's metabolism slowing down. Associated weakness is usually generalized, while the numbness is typically localized to the hands and feet.
