Humans are able to do many things in life and survive many conditions with the help of the functional human body. The human body is indeed a marvel as it contains a lot of structures and organs that stems from small cells and works in a system. When there is something wrong with the body, we may feel symptoms such as discomfort to the body part affected. In this DoctorOnCall’s article, we will learn about meralgia paresthetica, one of the many conditions that cause discomfort.
Meralgia is defined as pain in the thigh whereas paresthetica is the sensation of tingling, itching, burning or pain. Meralgia paresthetica is a condition of burning or painful sensation to the thigh. Specifically, meralgia paresthetica is a localised form of cutaneous dysaesthesia. This means that the condition has a changed sensation in the skin to the outer side of the thigh. The nerve affected in meralgia paresthetica is the lateral femoral cutaneous nerve (LFCN). Meralgia paresthetica occurs when this specific nerve is compressed or squeezed.
The LFCN itself is a sensory nerve of the skin. This means that meralgia paresthetica should not be associated with pain or weakness that radiates from the back as it should only be the skin that is sensitive to touch or becomes painful. There are a number of causes that could affect the LFCN. Among the causes are diabetes, low thyroid level (hypothyroidism), alcohol use disorder, lead poisoning, obesity, pregnancy, tumours and direct pressure on the LFCN such as from belts, restrictive clothing and tight seat belts. LFCN may also be affected by surgical procedure or direct nerve injury such as in spine surgery and hip placement surgery.
Due to the many causes that could lead to meralgia paresthetica, the number of people affected by the condition is relatively difficult to determine. It is said that meralgia paresthetica is much more common in women and in those aged 30 years or older. The condition is also commonly found in pregnant patients or obese even if it can occur in all ages. Those with carpal tunnel syndrome are likely to have meralgia paresthetica.
Meralgia paresthetica is characterised by numbness, tingling and burning pain. Pain usually occurs on one side, specifically on the outer side of the thigh but may extend to the outer side. Aching pain may be presented in the groin area or across the buttocks. The area affected may be sensitive towards light touch rather than firm pressure. In rare cases, itchiness may occur. Itchiness may cause the skin to have scratch marks, scarring and lichen simplex (a type of eczema) resulting from scratching and rubbing the affected area. The itch itself usually is not relieved by scratching or rubbing. Symptoms tend to get worse when the person stands and walks but lesser when sitting down.
Diagnosis of meralgia paresthetica is made by physician asking medical history and physical examination. Medical history of recent trauma, surgery or life events are typically included on top of the symptoms complaint by patients. Physical examination on the thigh is done by checking the sensory function of the affected legs and comparing with the other leg. Pressure might be placed on the thigh area to verify where the pain sensation occur and to assess the nerve affected. Imaging tests such as x-ray is done to help identify bone abnormalities that might put pressure on the nerve. CT scan or MRI may be requested if abnormality cannot be found in x-ray. Nerve conduction and electromyography is recommended in some case. Diagnosis may be confirmed with the procedure of injecting anaesthetic such as lidocaine to the site where the nerve is affected. If there is relief of symptoms after the procedure, it is highly suggestive of meralgia paraesthesia.
Treatment for meralgia paresthetica depends on the severity of the condition and catered based on the cause leading to pressure placed on the LFCN. Furthermore, treatment is not always necessary as symptoms can subside by itself. Treatment includes medication such as paracetamol, NSAIDs, lidocaine or capsaicin. Nerve block injection with anaesthesia or steroid may be considered in severe cases. It is rare for surgery to be done but is possible to help release nerve decompression. Some doctors might prescribe antidepressant or anticonvulsant to help ease pain caused by the nerve affected.
Beside treatment provided by health professionals, patients with mild symptoms may want to focus on things they can do themselves such as avoiding tight-fitting clothes and to plan for weight loss if obese the cause for symptoms. Placing ice packs on the area can reduce symptoms. Patients might also want to take time and rest from activity that could trigger symptoms. Physical therapy is reported to be effective in reducing symptoms. Physical therapists can recommend exercises that help to stretch muscle and tissue from pressing onto the LCFN. Exercising for 30 minutes at least 3 times a week should be able to help with meralgia paresthetica symptoms.
