For example, autistic children with developmental delay may be prescribed antipsychotics or mood stabilizers to help with their behavior. Use of psychotropic medications such as benzodiazepines in people with intellectual disability requires monitoring and vigilance as side effects occur commonly and are often misdiagnosed as behavioral and psychiatric problems. Epidemiology
Intellectual disability affects about 2–3% of the general population. 75–90% of the affected people have mild intellectual disability. Non-syndromic or idiopathic ID accounts for 30–50% of cases. About a quarter of cases are caused by a genetic disorder. Cases of unknown cause affect about 95 million people as of 2013. It is more common in males and in low to middle income countries. History
Intellectual disability has been documented under a variety of names throughout history. Throughout much of human history, society was unkind to those with any type of disability, and people with intellectual disability were commonly viewed as burdens on their families. Greek and Roman philosophers, who valued reasoning abilities, disparaged people with intellectual disability as barely human. The oldest physiological view of intellectual disability is in the writings of Hippocrates in the late fifth century BCE, who believed that it was caused by an imbalance in the four humors in the brain. In ancient Rome people with intellectual disabilities had limited rights and were generally looked down upon. They were considered property and could be kept slaves by their father. These people could also not marry, hold office, or raise children.
The thickness of the meniscus, its diminished vascular blood supply, and in some instances, weak capsular attachment, makes it more prone to tears compared to a normal meniscus. The anomaly in itself is asymptomatic; however, a tear of the meniscus can result in pain, swelling, and snapping in the affected knee. The orthopedic classification of discoid menisci includes: complete, incomplete or Wrisberg-ligament types as depicted here. Coverage of the lateral tibial plateau determines the designation of complete or incomplete. The Wrisberg-ligament type has an abnormal posterior attachment by attaching to part of the posterior cruciate ligament. Symptoms
Symptom is usually pain in the knee. And when the knee is bent or stretched it makes the sound of bouncing bones. Diagnosis
The transverse diameter of a normal meniscus is approximately 10 to 11 mm; therefore a normal meniscus body will be visible on only 2 slices of a MR with 4-5-mm sagittal slices. A discoid meniscus should be considered if more than two contiguous body segments are present. However, this method may lead to a false negative when evaluating people with the Wrisberg variant of discoid meniscus since it maintains a narrow crescent shape. Coronal and radial images of the meniscus are useful to demonstrate the extension of the aberrant meniscus into the joint as seen here. On coronal images, it is diagnosed when the horizontal measurement between the free margin and the periphery of the body is more than 1.4 cm.