Cause
The lateral femoral cutaneous nerve most often becomes injured by entrapment or compression where it passes between the upper front hip bone (ilium) and the inguinal ligament near the attachment at the anterior superior iliac spine (the upper point of the hip bone). Less commonly, the nerve may be entrapped by other anatomical or abnormal structures, or damaged by diabetic or other neuropathy or trauma such as from seat belt injury in an accident.The nerve may become painful over a period of time as weight gain makes underwear, belting or the waistband of pants gradually exert higher levels of pressure. Pain may be acute and radiate into the rib cage, and into the groin, thigh, and knee. Alternately, weight loss or aging may remove protective fat layers under the skin, so the nerve can compress against underwear, outer clothing, and—most commonly— by belting. Long periods of standing or leg exercise that increases tension on the inguinal ligament may also cause pressure.The lateral cutaneous nerve of the thigh can occasionally be damaged during laparoscopic hernia repair, or scarring from the operation can lead to meralgia paraesthetica. Diagnosis
Diagnosis is largely based on patient  description and relevant details about recent surgeries, hip injuries, or repetitive activities that could irritate the nerve.
Medical uses
Trospium chloride is used for the treatment of overactive bladder with symptoms of urge incontinence and frequent urination.It shouldnt be used with people who retain urine, who have severe digestive conditions, myasthenia gravis, narrow-angle glaucoma, or tachyarrhythmia.It should be used in caution with people who have problems with their autonomous nervous system (dysautonomia) or who have gastroesophageal reflux disease, or in whom fast heart rates are undesirable, such as people with hyperthyroidism, coronary artery disease and congestive heart failure.Trospium chloride is rated Pregnancy Category C, as there are no adequate and well-controlled studies of trospium chloride in pregnant women and there were signs of harm to the fetus in animal studies. The drug was excreted somewhat in the milk of nursing mothers. The drug was studied in children. Side effects
Side effects are typical of gastrointestinal effects of anticholinergic drugs, and include dry mouth, indigestion, and constipation. These side effects lead to problems with adherence, especially for older people. The only CNS side effect is headache, which was very rare. Tachycardia is a rare side effect. Mechanism of action
Trospium chloride is a muscarinic antagonist. Trospium chloride blocks the effect of acetylcholine on muscarinic receptors organs that are responsive to the compounds, including the bladder. Its parasympatholytic action relaxes the smooth muscle in the bladder. Receptor assays showed that trospium chloride  has negligible affinity for nicotinic receptors as compared to muscarinic receptors at concentrations obtained from therapeutic doses. Pharmacokinetics
After oral administration, less than 10% of the dose is absorbed.