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Happy AMC Awareness Day!

Amyoplasia

What is Amyoplasia?

Amyoplasia (A = no, myo=muscle, plasia=growth) means no muscle growth and is the most common type of AMC . It is estimated that one third of people born with AMC will have Amyoplasia, about 1 in 10,000 and it’s typically referred to as ‘Classical type AMC.’ This is considered the non-genetic form of AMC, meaning there has been no mutation in the genes to cause the condition to be present, and is not passed down from the parents.

Common traits of people with Amyoplasia are:

  • Affected in both arms and legs, and often the spine

  • Internally rotated shoulders

  • Extended elbows

  • Flexed wrists

  • Contractors of the fingers

  • Lower limbs can be stuck in various positions

  • Hips can have flexion/abduction/external rotational contractures (Buddha position or frog position)

  • Dislocated hips (about 30%)

  • Hip extension contractures (less common)

  • Flexion contractures of the knees

  • Extension contractures of the knees (less common)

  • Club feet

  • About 10% affected individuals may have squashed or missing fingers and toes. (less common)

  • Scoliosis (20-30%)

  • Splotchy red mark on the face (stork bite)

  • About 10% of Amyoplasia cases individuals may have abdominal abnormalities such as gastroschisis. Gastroschisis is a condition in which a hole is present in the wall of the abdomen allowing the intestines to intrude out of the abdominal space. (less common)

  • Normal or above average intelligence


References:

Amyoplasia – Arthrogryposis A Text Atlas. By: Judith G Hall MD, Lynn T Staheli MD, Kenneth M Jaffe MD, Diane O Paholke.

Amyoplaisia Revisited. By: Dr. Judith Hall

Distal

People with distal arthrogryposis (DA) are primarily affected in the hands and feet. Other areas and body functions can be affected depending on what type one has.  There are currently 20+ different types of DA all of which are linked back to genetic mutations. The best way to learn about you or your child’s specific type is to discuss it with health care providers and people in the AMC community. Here are a few of the more common types of distal arthrogryposis.

Type 1:

Type 1 is characterized by joint deformities that restrict movement in the hands and feet.

Common traits of distal type 1 are:

  • Facial sparing

  • Multiple contractures in hands and feet

  • Clenched hands

  • Overlapping fingers

  • A hand deformity in which all of the fingers are angled outward toward the little finger. This is called ulnar deviation

  • Hips and knees can be affected but it is less common and usually mild

  • Club feet

Type 2A (Freeman-Sheldon Syndrome):

Freeman-Sheldon Syndrome primarily affects the hands, feet and face. Distinctive facial features such as a small mouth, with purse lips give the appearance of a whistling face, hence also being called “Whistling Face Syndrome”.

Common traits of Freeman-Sheldon Syndrome are:

  • Prominent forehead and brow ridges

  • Widely spaced eyes

  • Deep set eyes

  • Outside corner of the eyes that point downward

  • Narrowing of the eye openings

  • Droopy eye lids

  • Eyes that do not look in the same direction

  • Sunken appearance of the middle of the face

  • Short nose and a long area between the nose and the mouth

  • Deep folds in the skin between the nose and lips

  • Full cheeks

  • Small mouth with pursed lips

  • Chin dimple shaped like an H or a V

  • Small tongue and jaw and a high arch in the roof of the mouth

  • Difficulty swallowing

  • Multiple contractors in hands and feet

  • A hand deformity in which all of the fingers are angled outward toward the little finger. This is called ulnar deviation.

  • Club feet

  • Spine that curves to the side (scoliosis)

  • Failure to gain weight and grow at expected weight

  • Respiratory complications

  • Speech problems

  • Hearing loss

  • Malignant hyperthermia (MH) is a condition where people have negative reactions to certain drugs used during general anesthesia. If it is of concern you can speak to your doctor about avoiding the use of succinylcholine during general anesthesia.

Type 2B (Sheldon-Hall Syndrome):

Sheldon-Hall Syndrome is similar to Freeman Sheldon Syndrome in that both have joint contractures of various areas of the body. However there are enough differences between the two that they are considered separate conditions.

Common traits of Sheldon-Hall Syndrome are:

  • Triangular shaped face

  • Outside corner of the eyes that point downward

  • Deep folds in the skin between the nose and lips

  • Attached ear lobes

  • Small mouth with pursed lips

  • High arched roof of the mouth

  • Extra folds of skin on the neck

  • Permanently bent fingers and toes

  • Overlapping fingers

  • A hand deformity in which all of the fingers are angled outward toward the little finger. This is called ulnar deviation.

  • Club feet

  • Vertical talus deformity

Type 9 (Beals Syndrome):

Beals syndrome is also known as congenital contractural archnodactyly (CCA) and has many of the same features as Marfan Syndrome. While Beals and Marfan share similar features they are also very distinct in the way they affect a person so it is important to obtain a accurate diagnosis so appropriate treatment can be given.

Common traits of Beals syndrome are:

  • Abnormally shaped ears resulting in a crumpled appearance

  • Unusually small jaw and or high arched palate

  • Abnormal short neck

  • Rounded upper back

  • Chest sinks in or sticks out

  • Long narrow body type with long limbs

  • Abnormally long slender fingers and toes

  • Joints being stuck in a permanent flexed position

  • Contractors in elbows and hands

  • Contractures in feet

  • Club feet

  • Contractures affecting the hips, knees and ankles

  • Curved spine (scoliosis)

  • Backward or lateral curved spine

  • Reduced bone mass

  • Underdeveloped muscles

  • Cardiovascular complications. It is recommended that those with Beals Syndrome have their heart monitored yearly as a precaution because on occasion heart issues like aortic enlargement or mitral valve regurgitation can occur.


Upper Extremities

This site is not intended to provide diagnosis, treatment or medical advice. It is for informational purposes only and is not intended to take the place of a trained medial professional who knows the details of your medical history. Readers are advised to consult with a physician or other qualified health professional regarding any treatment.

 

 Common Upper Extremity Characteristics:

  • Internal Rotation of the Shoulders

  • Extension or Flexion Contractures of the Elbow

  • Flexion Contractures of the Wrists

  • Thumb in Palm

  • Extension or Flexion Contractures of Individual Fingers

 

Courses of Treatment:

Therapy

Occupational Therapy (OT) and/ or Physical Therapy (PT) should begin as soon as possible to increase passive range of motion (ROM). This can be done through a clinic or at home with your local Early Intervention Provider. Either way you should be taught stretches to do at home with your child. The first year is crucial to gain range back in any joint. Here are some representative common stretches to try. Always speak to your child’s health care professional before starting any kind of new routine.  Read more about different Types of Therapy.

Stretches

A therapist should evaluate and identify joints requiring therapeutic attention, and then teach the caregiver how to correctly stretch the joints. The caregiver should practice stretching under supervision to insure proper technique to prevent accidental injuries, and to under exercise expectations. Issues such as previous surgeries, medication, bone density, etc., must be considered. Ranges of motion (ROM) exercises are individualized for each persons’ needs and should be directed by a therapist or a doctor. When performing stretches with a child, it is important to have the activity be fun and functional. Action songs, feeding, and dressing activities are all opportunities to naturally encourage upper body ROM activities.

Orthotic Management

Supporting the wrists in the best possible alignment should start as early as possible. Splinting the wrists and hands in infancy allows the soft tissue to lengthen and takes advantage of the infant’s flexibility. Splints may also be recommended for elbow or shoulder as well. Splints come in a wide variety of materials and shapes to help meet the individual’s specific needs. Sometimes several different orthotics are recommended at the same time, allowing greater stretch during inactive portions of the day while greater opportunity for functional activities at active times of the day. Here are some examples of types of upper extremity orthotics one may encounter:

Dynamic Splints: Dynamic splints push the joint into greater stretch when the limb relaxes. These orthotics typically are heavy and bulky so are not typically used for very small children. Dynamic splints are best used for joints that only move in one place such as an elbow. Some of the brands associated with this type of passive stretching include:

  • Bamboo Splint – a dynamic elbow splint for children with special needs that encourages extension of the elbow at more favorable angles in order to learn gross and fine motor skills as well as prevent undesired (oral/facial) interaction. Learn more: Bamboo Brace

  • Dyansplint – stretches joints that are lacking range of motion. Learn more: Dynasplint

  • JAS: Joint Active System- This is a device used to progressively gain range of motion but is used most frequently with individuals that have larger extremities. Learn more: Joint Active Systems

  • Ultraflex- Learn more: Ultraflex Systems

Static Splints: Static Splints are designed to hold an extremity or a joint at the same angle each time the brace is put on. It may be designed to allow support, holding the joints for stability while allowing functional tasks or for stretch, holding the joint at end range alignment while the person relaxes in the stretch. Some examples of static splints are as follows:

  • Benik – Soft neoprene splints with a metal bar that can be manipulated to provide different amounts of stretch. Learn more: Benik

  • Bivalved cast: The limb is casted using plaster and/ or fiberglass casting material. Once hardened, the cast is carefully removed then finished with moleskin and velcro to allow the individual to wear the cast for times of stretch but remove it when it is not needed.

  • Custom Molded Splints – These are fabricated by an OT, a PT, or an Orthotist. Usually these splints are fabricated out of a thermoplastic material (plastic which is heated to allow it to mold easily) molded directly on the individual’s extremity. Often the splints are secured with velcro straps. These orthotics hold the joint in one position to allow a prolonged stretch

  • Joe Cool Splint – Thumb abduction splints made of soft, flexible neoprene and have an adjustable hook and loop closure system. They do have a latex component, and they can be hand washed in cold water (line dry). Learn more: Joe Cool

 

Surgery

Often with children who have little passive elbow flexion, surgery is recommended. Doctors often recommend an elbow capsular release as early as a year, but usually within the first 5 years of life. This may be delayed to ensure that the child is ambulatory before changing the power of straight elbows. This is a surgery done by releasing the tight fibrous structures in the elbow that constrict movement. After this if a child still does not develop any active flexion or enough functional passive flexion doctors may recommend a muscle transfer to provide elbow bending (flexion). This depends on the quality of the donor muscles as well. Common muscles used are the muscle from the back (latissimus dorsi), or a part of the triceps (referred to as a split triceps transfer). Most doctors will not perform this surgery on children under 4 or 5, because the child needs to participate in the therapy following the surgery to re-train the muscle motion, wear splints to protect the transfer, etc. Every doctor is different in how aggressively they treat upper extremity problems. Some doctors do not believe this surgery is effective at all and may not offer this as an option to their patients. In addition there are also several hand surgeries that can be performed. For children with a serious flexion contracture in their wrists a small triangular wedge of bone (wedge osteotomy) can be removed to bring the wrist to a more neutral resting position. There are also surgeries for thumb-in-palm, if extremely severe, and various finger surgeries. With the future of needing thumb position for management of touch screens and electronic devices for text messaging, thumb alignment is being looked at more critically than it ever before, in order to maximize long term function.

Lower Extremities

Common Lower Extremity Characteristics:

  • Common contractures of the legs present at birth

  • Clubfeet or vertical talus,

  • Dislocated hips,

  • Externally rotated femurs

  • Flexion or extension contractures Of the knees

 Courses of Treatment:

 Therapy

Occupational Therapy (OT) and/ or Physical Therapy (PT) should begin as soon as possible to increase passive range of motion (ROM). This can be done through a clinic or at home with your local Early Intervention Provider. Either way you should be taught stretches to do at home with your child. The first year is crucial to gain range back in any joint. Here are some representative common stretches to try. Always speak to your child’s health care professional before starting any kind of new routine.  Read more about different Types of Therapy.

Stretches

A therapist should evaluate and identify joints requiring therapeutic attention, and then teach the caregiver how to correctly stretch the joints. The caregiver should practice stretching under supervision to insure proper technique to prevent accidental injuries, and to under exercise expectations. Issues such as previous surgeries, medication, bone density, etc., must be considered. Ranges of motion (ROM) exercises are individualized for each persons’ needs and should be directed by a therapist or a doctor. When performing stretches with a child, it is important to have the activity be fun and functional. Action songs, feeding, and dressing activities are all opportunities to naturally encourage upper body ROM activities.

We are researching orthotic management  and surgeries for lower extremities. Please check back soon.

Other Types of Arthrogryposis

This category is one of the most complex due to the fact that there are over 250 different diagnosis. Anything that is not Distal or Amyoplasia AMC goes into everything else category.

These include,but not limited too:

  • Pterygium syndromes

  • Lethal conditions

  • Atypical AMC

Pterygium syndromes

Pterygium syndrome is a congenital condition where webbing of the skin occurs around the joints causing a lack of muscle movement which then causes muscle weakness and joint contractures. Escobar syndrome and Lethal multiple pterygium syndrome are a few pterygium syndromes that are connected to AMC. Escobar type multiple pterygium syndrome (Escobar syndrome). There are different types of pterygium syndromes, Escobar being one of the more common types.

Common traits of Escobar syndrome are:

Webbing of the skin that affects

  • Skin on the neck

  • Fingers

  • Forearms

  • Inner thighs

  • Backs of knees

Other Features

  • Droopy eye lids

  • Outside corners of the eyes point downward

  • Skin folds covering the inner corner of the eyes

  • Low set ears

  • Small jaw

  • Arms and legs that cannot fully extend

  • Scoliosis

  • Respiratory distress at birth due to underdeveloped lungs

  • Males can have undescended testes

Lethal multiple pterygium syndrome is tragically individuals with this form of multiple pterygium syndrome typically do not make it past the 2nd or 3rd trimester of pregnancy.

Common traits of Lethal multiple pterygium syndrome are:

  • Abnormally small head

  • An opening in the roof of the mouth which is called cleft palet

  • Fluid filled sac typically found on the back of the neck

  • Excessive fluid in the body

  • Severe multiple contractors

  • Underdevelopment of the heart, lungs, or brain

  • Twisting of the intestines

  • Kidney abnormalities

  • A hole in the muscle that separates the abdomen from the chest cavity

Lethal multiple pterygium syndrome also falls under the Lethal conditions subgroup in the Everything else category.

Lethal Conditions

Tragically it is estimated that 1/3 of babies born with AMC will either be still born or die during their first year of life. There are several forms of AMC that can be deadly. As mentioned above Lethal Multiple pterygium syndrome is one. Another is Cerebro-oculo-facio-skeletal (COFS) as well as Restrictive dermopathy. Cerebro-oculo-facio-skeletal syndrome (COFS) . People with COFS will progressively deteriorate and sadly many times will not survive past 7 years old.

Common traits of COFS can be:

  • Extremely small head

  • Abnormally small eyes

  • Clouding of the eyes lens (cataract)

  • Horizontally narrow opening between the eye lids

  • Unusually prominent nose

  • Abnormally large ears

  • Upper lip over lapping lower lip

  • Abnormally long groove in upper lip

  • Unusually small jaw

  • Elbows with flexion contractures

  • One line in the palm of the hand formed by the fusion of two lines

  • Hip deformities

  • Knees with flexion contractures

  • Congenital vertical talus deformity (rocker bottom)

  • Grove over the length of the soles of the feet

  • Osteoporosis

  • Lack of muscle tone

  • Feeding difficulties

  • Vulnerability to respiratory infections

  • Failure to thrive

  • Developmental retardation

Restrictive dermopathy – Restrictive dermopathy is a lethal genetic skin condition that is connected to AMC. Unfortunately most born with Restrictive dermopathy will not make it past the first week of life.

Common traits of Restrictive dermopathy are:

  • delayed and stunted prenatal growth

  • reduced fetal movements

  • excessive amount of amniotic fluid

  • premature rupture of the membranes

  • thin tight skin

  • translucent skin

  • skin with damage at body parts that bend

  • facial dysmorphism

  • joint ankylosis (stiffness or fixation of joints and/or union of separate bones to

  • form a single bone)

  • death with in the first week of life

Atypical AMC

Atypical AMC is a term used to describe individuals with a unknown type of AMC.  AMC is rare and highly complex and it can take years for certain people to receive the diagnosis that caused AMC, and some may never receive a diagnosis at all. This can be a very long and frustrating journey for many families seeking answers about their loved ones with AMC, or a AMCer seeking answers for themselves.

AMCSI can connect you with support groups, other parents and caregivers through social media, mini-meet ups, and the yearly AMC conference. This will give you an enormous amount of moral support and also ideas for tools and adaptive equipment to help you or your child along.

AMC is a rare condition and it’s important to find an experienced doctor that will effectively treat you or your child. Whether you are Atypical or have a diagnosis you will need treatment and support groups are an excellent place to connect with others who can lead you in the right direction.

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