Meralgia paraesthetica refers to a nerve compression syndrome. It also goes by the name inguinal tunnel syndrome.
What is meralgia paraesthetica?
Meralgia paraesthetica is the term used in medicine when entrapment of the lateral cutaneus femoris nerve occurs. This nerve originates in the lumbar plexus. It also has general somatosensitive fibers. The thin nerve is located below the inguinal ligament and is responsible for supplying the thigh region up to the knee. In the case of meralgia paraesthetica, affected individuals suffer from pain that shoots in in an almost electrifying manner. Half of all patients also experience numbness. Meralgia paraesthetica is also known as inguinal tunnel syndrome or Bernhardt-Roth syndrome. Meralgia paraesthetica is one of the most common constriction syndromes. It occurs three times as often in males as in females. In principle, the onset of meralgia paraesthetica can occur in anyone.
Causes
Meralgia paraesthetica is mostly caused by mechanical pressure below the inguinal ligament. Likewise, however, traction or pressure effects in the course of the lateral cutaneus femoris nerve may be responsible for the development of the syndrome, which is especially true for the pelvic outlet region. In some cases, nerve damage in the course of medical treatment is also the reason for painful meralgia paraesthetica. This can be a puncture of the iliac crest, an abdominal wall opening or the removal of bone chips. The occurrence of meralgia paraesthetica is not infrequently favored by specific risk factors. These are primarily high pressure on the inguinal ligament due to pregnancy, overweight (obesity) or too tight belts or pants. An additional risk factor is diabetes mellitus. Also considered unfavorable are standing work activities that involve severe extension at the hip, long marches, and pronounced strength training at the hip, thigh, or abdomen. The pain of meralgia paraesthetica is caused by compression of the lateral cutaneous femoral nerve due to the passage of certain muscle fibers. The nerve bends about 90 degrees for this reason.
Symptoms, complaints, and signs
Meralgia paraesthetica is noticeable by burning pain that occurs on the outer side of the thigh. In addition, affected individuals suffer from unpleasant paresthesias such as numbness, sensory disturbances, or tingling. If the affected person bends their hip joint in the anterior direction, this results in an improvement of the symptoms. As the inguinal tunnel syndrome progresses, sensory disturbances such as hypalgesia or hypesthesia also become apparent. Approximately 20 percent of all patients suffer from symptoms on both sides of the body. Sometimes meralgia paraesthetica proves to be so unpleasant that even wearing clothes causes discomfort for those affected. However, loss of strength does not occur as a result of inguinal tunnel syndrome because there are no motor fibers in the lateral cutaneus femoris nerve.
Diagnosis and course of the disease
When meralgia paraesthetica is suspected, a visit to a physician is recommended. He begins his examination by taking the medical history of his patient. He then performs a thorough physical examination. This includes a neurological assessment, which usually reveals conspicuous sensory disturbances on the outer side of the thigh. In addition, the patient is usually sensitive to pressure pain, which the physician produces by applying pressure with two fingers to the spina iliaca anterior superior. At this point, the nerve passes through the inguinal ligament. In some patients, the physician may also derive abnormal somatosensory evoked potentials (SEP). In some cases, it is appropriate to perform a magnetic resonance imaging (MRI) scan to better evaluate the inguinal ligament structures. In most patients, meralgia paraesthetica takes a positive course. Thus, the pain improves in nine out of ten affected patients. However, every fourth patient suffers from spontaneous remission.
Complications
Meralgia paraesthetica causes the patient to experience very unpleasant feelings of paralysis or numbness. In most cases, affected individuals suffer from severe tingling or perceptual disturbances and sensory disturbances in the process. In some cases, pain may also occur, which in this case can also spread to other regions of the body. The quality of life is significantly reduced and limited by the sensory disturbances. Various paralyses can also lead to restrictions in everyday life, so that those affected are dependent on the help of other people due to meralgia paraesthetica. Pain occurs mainly in the form of pressure pain or strain pain. If there is pain at rest, it can also lead to sleep problems during sleep. The treatment of meralgia paraesthetica is carried out with the help of painkillers and various therapies. In most cases, there are no complications and the symptoms can be relatively well alleviated. However, it is usually impossible to predict whether a complete cure will be achieved. Life expectancy is usually not affected by the disease.
When should you see a doctor?
Perceptual disturbances or sensory disturbances on the skin should be evaluated by a physician. A tingling sensation on the skin or numbness are cause for concern. Often, the discomfort increases in severity and lasts for several days or weeks. If pain occurs on the outer side of the thigh, a doctor is needed. If locomotion is impaired due to symptoms or if there is unsteadiness in gait, the general risk of accident and injury increases. A doctor’s visit is necessary so that a treatment plan can be developed and potential risks can be minimized. Loss of strength, impairment in performing daily tasks, or a decrease in physical activity should be discussed with a physician. A doctor should be consulted if mobility is impaired or if the patient is unable to carry out usual occupational activities. If poor posture of the body develops due to the discomfort in the thigh, a doctor’s visit is advised. In case of permanent bad posture, damage to the skeletal system may develop, which should be prevented. If, in addition to the physical discomfort, mental abnormalities develop, a doctor is needed. In case of irritability, mood swings or withdrawal from social life, consultation with a doctor is recommended. If locomotion is greatly reduced, countermeasures should be worked out and taken.
Treatment and therapy
The therapy of meralgia paraesthetica depends on the triggering cause. It is also advisable to adapt the treatment individually to the needs of the patient. The longer the symptoms persist, the more the chances of recovery also worsen. The patient can also contribute to the improvement of his or her complaints by avoiding wearing tight clothing or exercising stretching postures with the hip joint. Conservative treatment usually involves the use of painkillers such as non-steroidal anti-inflammatory drugs (NSAIDs). Furthermore, preparations such as baclofen, gabapentin, pregabalin, carbamazepine as well as pyrimidine nucleosides can be administered. Complementary analgesics such as ibuprofen are also considered useful for therapy. In addition, treatment of existing underlying diseases is extremely important. If all these therapeutic measures do not bring about an improvement in the symptoms, surgical intervention may be considered. This involves either decompression of the affected nerve or even its severing. Severing the nerve causes complete deafness within the supply area. On the other hand, there is a possibility that the nerve ending that is formed in the process is highly sensitive to tissue pressure, which in turn results in new pain. Therefore, transection of the lateral cutaneal femoral nerve is rather discouraged. In contrast, a surgical procedure cuts the leaf portions at the inguinal ligament in such a way that movements of the hip joint can no longer trigger pain at the small nerve.
Outlook and prognosis
The prognosis of meralgia paraesthetica is generally favorable. Conservative treatment is initiated as soon as the diagnosis is made.In addition, the affected person can contribute significantly to the alleviation of his own complaints by changing the posture as well as the movement sequences for a positive development. Without medical care, the complaints are likely to remain constant. In addition, pain or other secondary diseases can occur due to the physical impairments. In particular, the muscular system is subjected to additional stress, so that poor posture and tension are to be expected in the event of an unfavorable course. Gait insecurities occur and general locomotion is more difficult. If the affected person consults a doctor, medication is prescribed as a first step. In addition, physiotherapeutic training can be ordered. In these, the affected person learns how to optimize his or her movements in the long term. If treatment with medication is not successful enough, surgery is performed. Although surgery is associated with risks, it is often the last option for achieving an improvement in the overall situation. Parallel to this, exercises should nevertheless be carried out for improved movement. If the surgical procedure and the wound healing are trouble-free, the affected person is discharged from treatment as recovered within a few weeks.
Prevention
Specific preventive measures against meralgia paraesthetica are not known. However, it is important to avoid certain risk factors, such as being overweight or wearing clothing that is too tight.
Aftercare
Because self-healing cannot occur in meralgia paraesthetica, follow-up care focuses on relieving symptoms and improving quality of life. Various complications and discomforts can occur with meralgia paraesthetica. In most cases, this disease causes various feelings of numbness or disturbances in perception. Those affected often suffer from tingling sensations in various parts of the body, and everyday life is also made significantly more difficult by these complaints. Temperature sensation is also reduced and made more difficult by meralgia paraesthetica. In children, the disease can lead to significant developmental disorders if not treated properly. Even when wearing clothes, these complaints can occur and have a negative impact on the daily life of the affected person. It is therefore not uncommon for many patients to develop psychological upsets or even depression, which should be clarified with a psychologist. Sometimes therapy is advisable. Contact with others who suffer from the same condition can also help to reduce suffering and promote the exchange of experiences.
What you can do yourself
Patients with meralgia paraesthetica are affected by unpleasant symptoms such as pain, tingling and numbness in the thigh due to the disease. The disturbances in sensitivity as well as pain perception have a negative impact on the quality of life. Patients see a doctor and attend all check-ups, which often take place at various medical specialists. After the diagnosis, the attending physicians determine a treatment plan, which the patient strictly adheres to in his or her own interest. The patient takes the prescribed painkillers at the prescribed time. If side effects result from the medication, the patient immediately reports this to the responsible physician or an emergency doctor. Many patients report unpleasant effects of too tight clothing on sensitivity disorders. Therefore, it is helpful to find individually appropriate clothing that does not aggravate the discomfort. Physiotherapy sometimes has a beneficial effect on the state of health and thus the quality of life of those affected. However, this is usually only an accompanying therapy, as the pain does not disappear from it. If desired, patients undergo surgery, in which surgeons often cut the nerve. Postoperatively, patients stay in the clinic and follow the doctors’ rules of conduct.
