Arthrogryposis Multiplex Congenita (AMC)

Arthrogryposis in Children

Finding out your child is diagnosed with any medical condition is disheartening. You have to deal with shock, disbelief, and anger. You then have to familiarize yourself with what it all means — and how it will affect the life of your baby and family. Things can feel even more frightening if the ailment is one most people have never heard of. Such is the case with arthrogryposis multiplex congenita. What is it? What causes it? And, what are the best treatment options for your child?

If you are the parent of an infant or small child with arthrogryposis multiplex congenita, it’s important to understand the causes and therapeutic options for this condition.

What is arthrogryposis multiplex congenita (AMC)?

Arthrogryposis multiplex congenita (AMC), or simply arthrogryposis, is a term that describes a number of conditions that work together to cause joint stiffness and contractures. AMC is a condition that occurs in newborns, causing decreased flexibility in the joints. While it is not progressive, your baby will need treatment to ensure they are able to use their joints in the future. It’s also important to note that arthrogryposis multiplex congenita is not a disease, but a symptom of an underlying health condition.

AMC typically affects the hands, wrists, elbows, shoulders, hips, knees, and feet joints. However, in more severe cases, it can also affect the jaw and spine. Sometimes, a baby will be born with an isolated joint contracture — such as clubfoot. But when the condition affects two or more parts of the body, it is known as arthrogryposis multiplex congenita. The severity of the ailment can also range from mild to severe, and the joints of the legs are usually the most affected. The condition has no cure.

Arthrogryposis Causes

In most cases, the exact cause of AMC is unknown, but there can be several potential causes. These include abnormal muscle development while in utero, an underlying neurological disorder affecting the connective tissue, not enough space for the baby to develop inside the womb and/or not enough amniotic fluid, malformed nervous system and/or spinal cord, and joints and bones not developing correctly. It’s also possible to occur as a result of too much tissue forming around joints — making it difficult to move them.

Arthrogryposis Symptoms

Arthrogryposis multiplex congenita is present at birth and is characterized by stiff and weak joints throughout the baby’s body. The most common telltale signs include:

  • Reduced range of motion in the affected area, which can include the hands, wrists, elbows, shoulders, hips, knees, and feet
  • Joints are permanently fixed at a bent or in a straightened position
  • Tube-shaped or underdeveloped limbs
  • Limited or absent movement of the joints
  • Limbs that feel like dough
  • Abnormally thin limbs
  • Muscle weakness or diminished strength
  • Cleft palate
  • In male babies, the testicles may fail to descend
  • In more rare forms, spinal curvature

Types of Arthrogryposis

There are two main types of arthrogryposis multiplex congenita:

  1. Amyoplastia (classic arthrogryposis): this involves multiple joints being affected, due to underdeveloped muscles and fatty degeneration.
  2. Distal arthrogryposis: this usually affects the hands and feet, but spares larger joints. This is usually associated with defective genes.

Arthrogryposis Risk Factors

Arthrogryposis multiplex congenita is a rare disorder that is diagnosed in approximately one out of every 3,000 births. Amyoplasia, the most common form of AMC that affects the upper and lower extremities, occurs in about one out of every 10,000 births.

  • Males and females tend to be equally affected, except in rare instances of X chromosome recessive disorders that affect males
  • There is no prevalence among any specific ethnic groups
  • Genetics are linked to less than a third of cases, and typically in the more rare forms of the disorder
  • There is some evidence that increased fetal movement may increase the risk of AMC

How is arthrogryposis diagnosed?

For prenatal cases, doctors or other medical professionals typically detect abnormalities when conducting ultrasound tests. This will result in additional testing, although there is no definitive prenatal diagnostic test for AMC.

AMC may also be detected after birth due to the presence of multiple joint contractures. It is not a specific disease in itself but is a descriptive term for the presence of two or more joint contractures in separate locations.

To confirm the diagnosis, doctors will typically perform the following steps:

  • Perform a full physical examination
  • Review family medical history
  • Order diagnostic tests such as blood work and muscle biopsy
  • Electromyography (EMG) testing to help to distinguish between different types of AMC

Arthrogryposis Treatment Options

Although there is not a cure, AMC is not a progressive disorder. While babies with arthrogryposis multiplex congenita will have to undergo treatment to assist them in moving their joints, their speech and cognitive abilities will not be affected. Therefore, with proper intervention — and in some cases, surgery — these children can lead productive and independent lives. Once diagnosed, the child may require several treatments:

Physical and Occupational Therapy

These therapies will include stretching and strengthening exercises, as well as mobility training and working with your child’s motor skills. They are designed to improve your child’s range of motion and foster independence.

Psychological Therapy

Since a child may need to undergo therapy for extended periods of time, it’s important to address how doing so may affect them emotionally. Therefore, this type of therapy is important to help them build their self-esteem.

Orthopedic Surgery

In some cases, the child may need surgical intervention to regain mobility of their joints. An orthopedic surgeon will conduct examinations to determine what would be the best course of action. Typical procedures include Achilles tendon release, limb lengthening, or spinal surgery.

Caring for an Infant With Arthrogryposis

To ensure the best chance of healthy development and good quality of life, infants and small children can benefit from specialized care and attention. From properly holding and feeding to helping achieve developmental milestones, parents should work with their pediatrician or orthopedic specialist to create an effective pediatric care plan.

Contact Sonas for Home Health Care in Florida

It can be hard to balance your time between work, home, and caring for a child. That’s why our team of skilled professionals at Sonas Home Health Care is here to help. We have been enforcing precautionary measures and following the Centers For Disease Control (CDC) guidelines for COVID-19 to ensure the safety and health of our clients and employees.

Our home health care services offer support in the comfort of your home. We refer loving and competent nurses to provide customized care for families — from a few hours a day to around-the-clock supervision. Contact us directly to speak with a home health care professional or request a free in-home assessment. Together we can determine the best plan of action to keep your loved ones happy and healthy.

If you or a loved one are considering Pediatric Home Health Care Services in Florida, contact the caring staff at Sonas Home Health Care. Call today at (888) 592-5855.

Jillian Miller
Jillian Miller BSN, RN
Director of Nursing at

This blog was reviewed by Jillian Miller BSN, RN — Director of Nursing for Sonas Home Health Care’s Tampa Bay market — for clinical accuracy. Jillian Miller has been a nurse for 16 years — working primarily in pediatrics. She believes the best part of working with the pediatric population is when you see smiles from clients when you first enter the room. She loves seeing the difference you can make in families’ lives while providing the best care possible for them.

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