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Chiari malformation (CM) is a structural defect in the cerebellum, characterized by a downward displacement of one or both cerebellar tonsils through the foramen magnum (the opening at the base of the skull). CMs can cause headaches, difficulty swallowing, vomiting, dizziness, neck pain, unsteady gait, poor hand coordination, numbness and tingling of the hands and feet, and speech problems. Less often, people may experience ringing or buzzing in the ears, weakness, slow heart rhythm, or fast heart rhythm, curvature of the spine ( scoliosis) related to spinal cord impairment, abnormal breathing, such as
central sleep apnea Central sleep apnea (CSA) or central sleep apnea syndrome (CSAS) is a sleep-related disorder in which the effort to breathe is diminished or absent, typically for 10 to 30 seconds either intermittently or in cycles, and is usually associated w ...
, characterized by periods of breathing cessation during sleep, and, in severe cases, paralysis. This can sometimes lead to non-communicating
hydrocephalus Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary inc ...
as a result of obstruction of
cerebrospinal fluid Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the ...
(CSF) outflow. The cerebrospinal fluid outflow is caused by phase difference in outflow and influx of blood in the
vasculature The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...
of the brain. The malformation is named after the Austrian pathologist
Hans Chiari Hans Chiari (4 September 1851 − 6 May 1916) was an Austrian pathologist, who was a native of Vienna. He was the son of gynecologist Johann Baptist Chiari (1817–1854), and brother to rhinolaryngologist Ottokar Chiari (1853–1918). Biograp ...
. A type II CM is also known as an Arnold–Chiari malformation in honor of Chiari and German pathologist
Julius Arnold Julius Arnold (19 August 1835 – 3 February 1915) was a German pathologist born in Zurich. He was the son of anatomist Friedrich Arnold (1803–1890). He studied medicine at the Universities of Heidelberg, Prague, Vienna and Berlin, where he wa ...
.


Signs and symptoms

Findings are due to
brain stem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is co ...
and lower cranial nerve dysfunction. Onset of symptoms are less likely to be present during adulthood in most patients. Younger children generally have a substantially different presentation of clinical symptoms from older children. Younger children are more likely to have a more rapid neurological degeneration with profound brain stem dysfunction over several days. * Neurogenic
dysphagia Dysphagia is difficulty in swallowing. Although classified under "symptoms and signs" in ICD-10, in some contexts it is classified as a condition in its own right. It may be a sensation that suggests difficulty in the passage of solids or liq ...
: Difficulty swallowing. Seen by poor feeding in patient. * Cyanosis: Bluish discoloration of skin while feeding. * Weak crying * Facial weakness * Aspiration * Headaches aggravated by
Valsalva maneuver The Valsalva maneuver is performed by a forceful attempt of exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut while expelling air out as if blowing up a balloon. Variations of the maneuver can ...
s, such as yawning, laughing, crying, coughing, sneezing or straining, bending over, or getting up suddenly *
Tinnitus Tinnitus is the perception of sound when no corresponding external sound is present. Nearly everyone experiences a faint "normal tinnitus" in a completely quiet room; but it is of concern only if it is bothersome, interferes with normal hearin ...
(ringing in the ears) *
Lhermitte's sign Lhermitte phenomenon, also called the barber chair phenomenon, is an uncomfortable "electrical" sensation that runs through the back and into the limbs. The sensation can feel like it goes up or down the spine. It is painful for some, although oth ...
(electrical sensation that runs down the back and into the limbs) *
Vertigo Vertigo is a condition where a person has the sensation of movement or of surrounding objects moving when they are not. Often it feels like a spinning or swaying movement. This may be associated with nausea, vomiting, sweating, or difficulties w ...
(dizziness) * Nausea * Schmahmann syndrome *
Nystagmus Nystagmus is a condition of involuntary (or voluntary, in some cases) eye movement. Infants can be born with it but more commonly acquire it in infancy or later in life. In many cases it may result in reduced or limited vision. Due to the invol ...
(irregular eye movements; typically, so-called "downbeat nystagmus") * Facial pain * Muscle weakness * Impaired gag reflex *
Dysphagia Dysphagia is difficulty in swallowing. Although classified under "symptoms and signs" in ICD-10, in some contexts it is classified as a condition in its own right. It may be a sensation that suggests difficulty in the passage of solids or liq ...
(difficulty swallowing) *
Restless leg syndrome Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is generally a long-term disorder that causes a strong urge to move one's legs. There is often an unpleasant feeling in the legs that improves somewhat by moving them. This ...
*
Sleep apnea Sleep apnea, also spelled sleep apnoea, is a sleep disorder in which pauses in breathing or periods of shallow breathing during sleep occur more often than normal. Each pause can last for a few seconds to a few minutes and they happen many tim ...
* Sleep disorders * Impaired coordination * Severe cases may develop all the symptoms and signs of a
bulbar palsy Bulbar palsy refers to a range of different signs and symptoms linked to impairment of function of the glossopharyngeal nerve (CN IX), the vagus nerve (CN X), the accessory nerve (CN XI), and the hypoglossal nerve (CN XII). It is caused by a low ...
* Paralysis due to pressure at the cervico-medullary junction may progress in a so-called "clockwise" fashion, affecting the right arm, then the right leg, then the left leg, and finally the left arm; or the opposite way around. * Papilledema on fundoscopic exam due to
Increased intracranial pressure Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and at rest, is normally 7–15 mmHg for a supine adult. Th ...
*
Pupillary dilation Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve. A constriction response ( miosis), is the narrowing of the pupil, which may be caused by scleral buckles or drugs such ...
*
Dysautonomia Dysautonomia or autonomic dysfunction is a condition in which the autonomic nervous system (ANS) does not work properly. This may affect the functioning of the heart, bladder, intestines, sweat glands, pupils, and blood vessels. Dysautonomia ha ...
:
tachycardia Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal ( ...
(rapid heart), syncope (fainting),
polydipsia Polydipsia is excessive thirst or excess drinking.Porth, C. M. (1990). ''Pathophysiology: Concepts of altered health states''. Philadelphia: J.B. Lippincott Company. The word derives from the Greek () "very thirsty", which is derived from (, "mu ...
(extreme thirst), chronic fatigue * Apnea: Sudden pause of breathing, usually during sleep. *
Opisthotonos Opisthotonus or opisthotonos (from grc, ὄπισθεν, translit=opisthen, lit=behind and grc, τόνος, translit=tonos, lit=tension, label=none) is a state of severe hyperextension and spasticity in which an individual's head, neck and spinal ...
: Spasm of the head which causes head to arch backwards. More common in infants than adults. * Stridor The blockage of
cerebrospinal fluid Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the ...
(CSF) flow may also cause a syrinx to form, eventually leading to
syringomyelia Syringomyelia is a generic term referring to a disorder in which a cyst or cavity forms within the spinal cord. Often, syringomyelia is used as a generic term before an etiology is determined. This cyst, called a syrinx, can expand and elongate o ...
. Central cord symptoms such as hand weakness, dissociated sensory loss, and, in severe cases, paralysis may occur.


Syringomyelia

Syringomyelia is most often chronic progressive degenerative disorder characterized by a fluid-filled
cyst A cyst is a closed sac, having a distinct envelope and division compared with the nearby tissue. Hence, it is a cluster of cells that have grouped together to form a sac (like the manner in which water molecules group together to form a bubble) ...
located in the
spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...
. However, there can be also cases where the syrinx in terms of size and extent of symptoms actually stays stable throughout a lifetime. Syringomyelia symptoms include pain, weakness, numbness, and stiffness in the back, shoulders, arms or legs. Other symptoms include headaches, the inability to feel changes in the temperature, sweating, sexual dysfunction, and loss of bowel and bladder control. It is usually seen in the
cervical In anatomy, cervical is an adjective that has two meanings: # of or pertaining to any neck. # of or pertaining to the female cervix: i.e., the ''neck'' of the uterus. *Commonly used medical phrases involving the neck are **cervical collar **cerv ...
region but can extend into the medulla oblongata and
pons The pons (from Latin , "bridge") is part of the brainstem that in humans and other bipeds lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. The pons is also called the pons Varolii ("bridge of Va ...
or it can reach downward into the
thoracic The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...
or lumbar segments. Syringomyelia is often associated with type I Chiari malformation and is commonly seen between the C-4 and C-6 levels. The exact development of syringomyelia is unknown but many theories suggest that the herniated tonsils in type I Chiari malformations cause a "plug" to form, which does not allow an outlet of CSF from the brain to the spinal canal. Syringomyelia is present in 25% of patients with type I Chiari malformations.


Pathophysiology

The most widely accepted pathophysiological mechanism by which Chiari type I malformations occur is by a reduction or lack of development of the posterior fossa as a result of congenital or acquired disorders. Congenital causes include hydrocephalus, craniosynostosis (especially of the lambdoid suture),
hyperostosis Hyperostosis is an excessive growth of bone. It may lead to exostosis. It occurs in many musculoskeletal disorders. See also * Diffuse idiopathic skeletal hyperostosis Diffuse idiopathic skeletal hyperostosis (DISH) is a condition characteri ...
(such as craniometaphyseal dysplasia,
osteopetrosis Osteopetrosis, literally "stone bone", also known as marble bone disease or Albers-Schönberg disease, is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis ...
, erythroid hyperplasia), X-linked vitamin D-resistant rickets, and neurofibromatosis type I. Acquired disorders include space occupying lesions due to one of several potential causes ranging from brain tumors to hematomas. Traumatic brain injury may cause delayed acquired Chiari malformation, but the pathophysiology of this is unknown. Additionally, ectopia may be present but asymptomatic until a
whiplash Whiplash may refer to: * The long flexible part of a whip * Whiplash (medicine), a neck injury ** Whiplash Injury Protection System (WHIPS), in automobiles Film and television * ''Whiplash'' (1948 film), a US film noir about a boxer * ''Whiplas ...
injury causes it to become symptomatic. Some neurological experts believe that Chiari malformation type I is developed as a result of Filum Disease, an abnormal traction of the spinal cord caused by an excessively tense Filum terminale. This theory was first introduced by Dr. Miguel B. Royo Salvador in 1993.


Diagnosis

Diagnosis is made through a combination of patient history, neurological examination, and medical imaging. Magnetic resonance imaging (MRI) is considered the preferred imaging modality for Chiari malformation. The MRI visualizes neural tissue such as the cerebellar tonsils and spinal cord as well as bone and other soft tissues. CT and CT myelography are other options and were used prior to the advent of MRI, unfortunately the resolution of CT based modalities do not characterize syringomyelia and other neural abnormalities as well. By convention, the cerebellar tonsil position is measured relative to the basion-opisthion line, using sagittal T1 MRI images or sagittal CT images. The selected cutoff distance for abnormal tonsil position is somewhat arbitrary, as not every person will be symptomatic at a certain amount of tonsil displacement, and the probability of symptoms and syrinx increases with greater displacement; however, greater than 5 mm is the most frequently cited cutoff number, though some consider 3–5 mm to be "borderline,"; pathological signs and syrinx may occur beyond that distance. One study showed little difference in cerebellar tonsil position between standard recumbent MRI and upright MRI for patients without a history of whiplash injury. Neuroradiological investigation is used to first rule out any intracranial condition that could be responsible for tonsillar herniation. Neuroradiological diagnostics evaluate the severity of crowding of the neural structures within the posterior cranial fossa and their pressure against the foramen magnum. Chiari 1.5 is a term used when both brainstem and tonsillar herniation through the foramen magnum are present. The diagnosis of a Chiari II malformation can be made prenatally, through
ultrasound Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies ...
.


Classification

In the late 19th century, Austrian pathologist
Hans Chiari Hans Chiari (4 September 1851 − 6 May 1916) was an Austrian pathologist, who was a native of Vienna. He was the son of gynecologist Johann Baptist Chiari (1817–1854), and brother to rhinolaryngologist Ottokar Chiari (1853–1918). Biograp ...
described seemingly related anomalies of the hindbrain, the so-called Chiari malformations I, II and III. Later, other investigators added a fourth (Chiari IV) malformation. The scale of severity is rated I – IV, with IV being the most severe. Types III and IV are very rare. Since Dr. Chiari's original descriptions Chiari 0, 1.5, 3.5, and 5 have been described in the medical literature.


Types of Chiari malformation

Other conditions sometimes causally associated with Chiari malformation include hydrocephalus,
syringomyelia Syringomyelia is a generic term referring to a disorder in which a cyst or cavity forms within the spinal cord. Often, syringomyelia is used as a generic term before an etiology is determined. This cyst, called a syrinx, can expand and elongate o ...
, spinal curvature,
tethered spinal cord syndrome Tethered cord syndrome (TCS) refers to a group of neurological disorders that relate to malformations of the spinal cord.connective tissue disorder A connective tissue disease (collagenosis) is any disease that has the connective tissues of the body as a target of pathology. Connective tissue is any type of biological tissue with an extensive extracellular matrix that supports, binds togeth ...
s such as Ehlers-Danlos syndrome and Marfan syndrome. Chiari malformation is the most frequently used term for this set of conditions. The use of the term "Arnold–Chiari malformation" has fallen somewhat out of favor over time, although it is used to refer to the type II malformation. Current sources use "Chiari malformation" to describe its four specific types, reserving the term "Arnold-Chiari" for type II only. Some sources still use "Arnold-Chiari" for all four types. Chiari malformation or Arnold–Chiari malformation should not be confused with Budd-Chiari syndrome, a hepatic condition also named for
Hans Chiari Hans Chiari (4 September 1851 − 6 May 1916) was an Austrian pathologist, who was a native of Vienna. He was the son of gynecologist Johann Baptist Chiari (1817–1854), and brother to rhinolaryngologist Ottokar Chiari (1853–1918). Biograp ...
. In Pseudo-Chiari Malformation, leaking of CSF may cause displacement of the cerebellar tonsils and similar symptoms sufficient to be mistaken for a Chiari I malformation.


Treatment

While there is no current cure, the treatments for Chiari malformation are surgery and management of symptoms, based on the occurrence of clinical symptoms rather than the radiological findings. The presence of a syrinx is known to give specific signs and symptoms that vary from dysesthetic sensations to algothermal dissociation to
spasticity Spasticity () is a feature of altered skeletal muscle performance with a combination of paralysis, increased tendon reflex activity, and hypertonia. It is also colloquially referred to as an unusual "tightness", stiffness, or "pull" of muscles ...
and
paresis In medicine, paresis () is a condition typified by a weakness of voluntary movement, or by partial loss of voluntary movement or by impaired movement. When used without qualifiers, it usually refers to the limbs, but it can also be used to desc ...
. These are important indications that decompressive surgery is needed for patients with Chiari Malformation Type II. Type II patients have severe brain stem damage and rapidly diminishing neurological response. Decompressive surgery involves removing the
lamina Lamina may refer to: Science and technology * Planar lamina, a two-dimensional planar closed surface with mass and density, in mathematics * Laminar flow, (or streamline flow) occurs when a fluid flows in parallel layers, with no disruption betwee ...
of the first and sometimes the second or third cervical vertebrae and part of the occipital bone of the
skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...
to relieve pressure. The flow of spinal fluid may be augmented by a shunt. Since this surgery usually involves the opening of the
dura mater In neuroanatomy, dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system. ...
and the expansion of the space beneath, a dural graft is usually applied to cover the expanded posterior fossa. A small number of neurological surgeons believe that detethering the spinal cord as an alternate approach relieves the compression of the brain against the skull opening (foramen magnum), obviating the need for decompression surgery and associated trauma. However, this approach is significantly less documented in the medical literature, with reports on only a handful of patients. The alternative spinal surgery is also not without risk. Complications of decompression surgery can arise. They include bleeding, damage to structures in the brain and spinal canal, meningitis, CSF fistulas, occipito-cervical instability and pseudomeningeocele. Rare post-operative complications include hydrocephalus and
brain stem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is co ...
compression by retroflexion of odontoid. Also, an extended CVD created by a wide opening and big duroplasty can cause a cerebellar "slump". This complication needs to be corrected by cranioplasty. In certain cases, irreducible compression of the brainstem occurs from in front (anteriorly or ventral) resulting in a smaller posterior fossa and associated Chiari malformation. In these cases, an anterior decompression is required. The most commonly used approach is to operate through the mouth (transoral) to remove the bone compressing the brainstem, typically the odontoid. This results in decompressing the brainstem and therefore gives more room for the cerebellum, thus decompressing the Chiari malformation. Arnold Menzes, MD, is the neurosurgeon who pioneered this approach in the 1970s at the University of Iowa. Between 1984 and 2008 (the MR imaging era), 298 patients with irreducible ventral compression of the brainstem and Chiari type 1 malformation underwent a transoral approach for ventral cervicomedullary decompression at the University of Iowa. The results have been excellent resulting in improved brainstem function and resolution of the Chiari malformation in the majority of patients.


Epidemiology

Congenital Chiari I malformation, defined as tonsilar
herniation A hernia is the abnormal exit of tissue or an organ, such as the bowel, through the wall of the cavity in which it normally resides. Various types of hernias can occur, most commonly involving the abdomen, and specifically the groin. Groin hernia ...
s of 3 to 5 mm or greater, was previously believed to be in the range of one per 1000 births, but is likely much higher. Women are three times more likely than men to have a congenital Chiari malformation. Type II malformations are more prevalent in people of Celtic descent. A study using upright MRI found cerebellar tonsillar ectopia in 23% of adults with headache from motor-vehicle-accident head trauma. Upright MRI was more than twice as sensitive as standard MRI, likely because gravity affects cerebellar position. Cases of congenital Chiari malformation may be explained by evolutionary and genetic factors. Typically, an infant's brain weighs around 400g at birth and triples to 1100-1400g by age 11. At the same time the cranium triples in volume from 500 cm3 to 1500 cm3 to accommodate the growing brain. During human evolution, the skull underwent numerous changes to accommodate the growing brain. The evolutionary changes included increased size and shape of the skull, decreased basal angle and basicranial length. These modifications resulted in significant reduction of the size of the posterior fossa in modern humans. In normal adults, the posterior fossa comprises 27% of the total intracranial space, while in adults with Chiari Type I, it is only 21%. H. neanderthalensis had platycephalic (flattened) skulls. Some cases of Chiari are associated with platybasia (flattening of the skull base).


History

The history of Chiari malformation is described below and categorized by the year: * 1883: Cleland was the first to describe Chiari II or Arnold–Chiari malformation on his report of a child with spina bifida, hydrocephalus, and anatomical alterations of the cerebellum and brainstem. * 1891:
Hans Chiari Hans Chiari (4 September 1851 − 6 May 1916) was an Austrian pathologist, who was a native of Vienna. He was the son of gynecologist Johann Baptist Chiari (1817–1854), and brother to rhinolaryngologist Ottokar Chiari (1853–1918). Biograp ...
, a Viennese pathologist, described the case of a 17-year-old female with elongation of the tonsils into cone shaped projections which accompany the medulla and are crammed into the spinal canal. * 1907: Schwalbe and Gredig, pupils of German pathologist
Julius Arnold Julius Arnold (19 August 1835 – 3 February 1915) was a German pathologist born in Zurich. He was the son of anatomist Friedrich Arnold (1803–1890). He studied medicine at the Universities of Heidelberg, Prague, Vienna and Berlin, where he wa ...
, described four cases of meningomyelocele and alterations in the brainstem and cerebellum, and gave the name "Arnold-Chiari" to these malformations. * 1932: Van Houweninge Graftdijk was the first to report the surgical treatment of Chiari malformations. All patients died from surgery or postoperative complications. * 1935: Russell and Donald suggested that decompression of the spinal cord at the foramen magnum might facilitate the CSF circulation. * 1940: Gustafson and Oldberg diagnosed Chiari malformation with syringomyelia. * 1974: Bloch ''et al.'' described the tonsils position to be classified between 7 mm and 8 mm below cerebellum. * 1985: Aboulezz used MRI for discovery of extension


Society and culture

The condition was brought to the mainstream on the series '' CSI: Crime Scene Investigation'' in the tenth-season episode "Internal Combustion" on February 4, 2010. Chiari malformation was briefly mentioned on the medical drama '' House M.D.'' in the fifth-season episode " House Divided", It was the focus of the sixth-season episode " The Choice." It is also the focus of ''Private Practice'' Season 4 episode 4, where a pregnant woman is diagnosed with it. It was the a cause of death on the reality television series ''Dr. G: Medical Examiner'' in the sixth-season episode "Bruised and Battered". It was also mentioned in the medical drama ''
A Gifted Man ''A Gifted Man'' is an American fantasy medical drama television series that premiered on CBS on September 23, 2011. The series is about a talented but self-absorbed surgeon ( Patrick Wilson) who starts questioning his purpose in life when he is ...
'', in the first-season episode "In Case of Separation Anxiety". It is also featured in the 3rd and 4th episode of the 7th season of the series '' Rizzoli & Isles'' where Dr. Maura Isles is diagnosed with the condition.


Notable people

*
Rosanne Cash Rosanne Cash (born May 24, 1955) is an American singer-songwriter and author. She is the eldest daughter of country musician Johnny Cash and Vivian Liberto Cash Distin, Johnny Cash's first wife. Although she is often classified as a country art ...
– U.S. singer-songwriter; daughter of Johnny Cash * Julia Clukey – U.S. luge competitor for Team USA in 2010 Vancouver Winter Olympics *
Joanna David Joanna David (born Joanna Elizabeth Hacking; 17 January 1947) is an English actress, best known for her television work. Life David was born in Lancaster, England, to Davida Elizabeth (''née'' Nesbitt) and John Almond Hacking. In 1971, she ...
– British television and stage actress * J. B. Holmes – U.S. professional golfer * Marissa Irwin – U.S. fashion model with Chiari secondary to Ehlers-Danlos syndrome * Bobby Jones – U.S. World Golf Hall of Fame golfer and founder of the Augusta National Golf Club * Allysa Seely – U.S. Gold Medalist at the 2016 Summer Paralympics in the paratriathlon * Leah Shapiro – U.S. drummer for the band Black Rebel Motorcycle Club * Michelle Stilwell – Canadian wheelchair racer and politician *
Rachid Taha Rachid Taha ( ar, رشيد طه, Latn, ar, Rashīd Ṭāhā, ; 18 September 1958 – 12 September 2018) was an Algerian singer and activist based in France described as "sonically adventurous". His music was influenced by many different styles ...
– Algerian singer * Sabre Norris – Australian skateboarder and surfer


See also

* Hypermobility spectrum disorder


References

{{DEFAULTSORT:Arnold-Chiari Malformation Congenital disorders of nervous system