Anterior cutaneous nerve entrapment syndrome (ACNES) is a condition that occurs when the anterior cutaneous nerve, a branch of the femoral nerve, becomes compressed or entrapped. This can cause pain, numbness, and tingling in the front of the thigh. It is most commonly caused by tight clothing, such as jeans or shorts, or by activities that involve repetitive flexion and extension of the hip, such as cycling or running. Treatment typically involves avoiding activities that aggravate the condition, stretching, and physical therapy. In some cases, surgery may be necessary to release the entrapped nerve.