Summary – Nerve entrapment occurs when a nerve entrapment syndrome causes a nerve or nerves to become pinched or compressed. Nerve entrapment results in abnormal functioning of the nerve. Typical symptoms of nerve entrapment include numbness, pain, and loss of function of the affected area. Common conditions that cause nerve entrapment in the lower limb include slipped or herniated disc, spinal stenosis, spondylolisthesis may cause nerve entrapment of the spine and tarsal tunnel syndrome.
People at risk for developing slipped disc, herniated disc, spinal stenosis and spondylolisthesis include older adults and the elderly, people with osteoporosis, who are overweight or obese, or have strained or injured the back.
Other risk factors for developing nerve entrapment include having rheumatoid arthritis, menopause, hypothyroidism, diabetes and acromegaly. These conditions can result in compression of a nerve by causing fluid retention, swelling, or abnormal bone anatomy.
Literature – Beltran, L., Bencardino, J., Ghazikhanian, V., Beltran, J. (2010). Entrapment Neuropathies III: Lower Limb. Seminars in Musculoskeletal Radiology; 14(5): 501-511
McCrory, P., Bell, S., Bradshaw, C. (2002). Nerve Entrapments of the Lower Leg, Ankle and Foot in Sport. Sports Medicine; 32(6): 371-391
Neal, S., Fields, K. (2010). Peripheral Nerve Entrapment and Injury in the Upper Extremity. American Family Physician; 81(2): 147-155
Diagnostic tip – Making a diagnosis of nerve entrapment begins with taking a thorough medical history, including symptoms and the types of activities a person is performing often that may lead to nerve entrapment. A physical and thorough neurological examination is also done. This includes having the patient perform certain movements to see if they result in pain or numbness.
It is possible that a diagnosis of nerve entrapment can be missed or delayed because early symptoms can be mild or similar to symptoms of other conditions, such as bursitis. For more information on diseases and conditions that can mimic nerve entrapment, refer to misdiagnosis of nerve entrapment.
Testing or imagery – Diagnostic testing may include special tests that test the nerves and muscles. These include an electromyography, which tests muscles movement, and a nerve conduction velocity test, which identifies how fast nerves conduct electrical impulses.
Medical testing may also include tests that can help determine any underlying medical disease or conditions, such as an X-ray, which can reveal a bone fracture, which may cause nerve entrapment. Blood tests may be done to rule-out or diagnose other conditions that can lead to nerve entrapment, such as diabetes or hypothyroidism.
Summary – Compression of a nerve that becomes trapped in a confined space due to any cause e.g. trauma, inflammation or a disease process. This usually occurs near joints. The resulting pressure on the nerve can be very painful and if left untreated can result in damage to the nerve and eventually muscle weakness and wasting.
How does this occur? – Conditions such as bone spurs, joint swelling due to injury, cysts and trauma can result in nerve entrapment. The exact symptoms will depend on which nerve is trapped and the duration and severity of the entrapment.
How can this be helped? – Treatment for nerve entrapment varies depending on the type of nerve affected, the severity of symptoms, the presence of complications, a person’s age and medical history, and the type of work and activities a person does. Early diagnosis and treatment can reduce symptoms and permanent complications, such as disability. Treatment options include modifying activities, orthopaedic and orthotic devices, medication, physical therapy, occupational therapy and surgery.
Who can help? – Depending on where the nerve entrapment occurs a range of medical professionals may be able to help including your local GP, podiatrist (lower limb), physiotherapist (back and upper limb), and chiropractor.
It is vitally important that if you have any nerve entrapment symptoms to be assessed early to prevent the risk of further complications.