Skeleton and Joints
It is often the skeletal (orthopedic) features that first lead a person to suspect Marfan syndrome. Following is an overview of the orthopedic issues. What are the primary orthopedic problems caused by Marfan syndrome?
Orthopedics involves the skeleton and ligaments, and the muscles that move them. Aspects of the skeleton that are unique in individuals with Marfan syndrome are differences in the growth of bone and decreased ligamentous support. There is great variability among people who are affected with the disorder in the severity of these manifestations. In only about one-third of people with Marfan syndrome do these orthopedic concerns become severe enough to see an orthopedic doctor.
The growth differences in the bones in people with Marfan syndrome cause affected individuals to have long, slender arms, legs, fingers and feet. They also include inward or outward growth of the breastbone (sternum). A few Marfan children develop hip sockets which become too "pushed in" or deepened with growth (protrusio acetabulae). Claw or hammer toes are another possible growth difference in people with Marfan syndrome.
Ligament relaxation occurs mainly where there is constant pressure. This shows up most often in the foot, where the arch becomes stretched out and flattened, leading to flat feet (pes planus). It may also occur in the spine, where a side curvature (scoliosis) or a forward curvature (kyphosis) may develop. Dislocation of the major joints, such as the shoulders, knees and hips, however, are not much more common in people with Marfan syndrome than in the general public.
Some people with Marfan syndrome have aches and pains in the back, arms, legs or feet. These can be partially prevented by keeping in good physical condition with regular exercise (four or five times per week) that does not stress the aorta, applying ice or heat, stretching or taking a mild analgesic (such as Tylenol®) in accordance with a doctor’s recommendation.
What is scoliosis and how is it diagnosed?
Scoliosis is a spinal curvature in which the vertebrae twist, usually into an S-shape or spiral shape. It is caused by the abnormally loose ligaments of the spine and the rapid growth of the child with Marfan syndrome. Scoliosis can affect any part of the spine, and it may be mild or severe. About 50 percent of people with Marfan syndrome develop scoliosis, although only about one-third of those with scoliosis need treatment.
All children are usually checked for scoliosis in school in the fifth grade. However, children with Marfan syndrome should be checked for scoliosis by their pediatricians even before fifth grade, then at each yearly physical exam. This is done by having the child bend forward while the back is examined by the doctor or nurse (figure 1). If a child does not show signs of scoliosis by the start of middle school, he or she probably will not develop it later to a significant degree. Scoliosis rarely begins in adulthood.  figure 1 The term progression refers to scoliosis becoming more severe. The chance of a curve progressing, or worsening, depends on how much growth a person has left and the size of the current curve. Curves are measured by the angle between the vertebrae (as seen on the X-ray), given as a number or degrees (º) (figure 2). A small curve (less than 20º) in an adolescent has a low chance of worsening. A moderate curve (20º-40º) has a greater chance of worsening in a child or adolescent. A large curve (more than 40º) almost certainly will progress, in either a child or an adult. This is because there is already so much imbalance in the spine that gravity will continue to worsen it. figure 2 When is a back brace recommended?
Treatment is sometimes recommended because scoliosis can cause many problems, including back pain, decreased lung function, and posture and shape disturbances. A child with scoliosis should have his or her back checked one or two times per year. An adult with scoliosis should have it examined every one to three years. If the curve is increasing and is more than 20º, some treatment is usually recommended in growing children and adolescents because exercise alone will not prevent a curve from progressing.
A back brace is often recommended for children with scoliosis between 20º and 40º. A brace is a custom-molded, padded plastic “jacket” that fits around the trunk, from shoulders to waist, and temporarily straightens the spine. As a result, it stops the worsening process. However, the brace cannot permanently straighten the curve. When the brace is removed, the spine will gradually return to its original curvature.
The goal of the brace is simply to keep the curve from getting worse with growth. It is usually worn 23 hours per day. The time off is for bathing/showering and dressing. In addition, the patient may remove the brace for swimming or organized sports, if necessary. The brace is worn until growth is complete. For girls, this is usually until age 14 or 15; for boys, it is 16 to 17.
The brace works in many, but not all, people with Marfan syndrome. If the curve is too great or progressive, bracing will not prevent the need for surgery.
When is surgery necessary to treat scoliosis?
If the curve becomes more than 40º to 50º, surgery is considered so that lung problems, back pain and further deformity can be avoided. If surgery is chosen, it is usually safer and more effective to correct the curve before it progresses further. Therefore, if the curve is greater than 40º, the affected person should talk to his or her doctor about therapy or treatment options.
Scoliosis surgery involves straightening the spine with metal rods and fusing it in the straightened position. The rods are placed deep under the back muscles, against the vertebrae, so that they cannot be felt. While the rods are holding the spine straight, bone chips are growing together to fuse the spine and permanently hold it straight. Sometimes, the surgery is performed through a posterior approach. Sometimes, if the curve is very large or rigid, it is performed using both an anterior approach, going to the spine from the front and removing the deformed spinal disks, and posterior approach.
Scoliosis surgery is usually successful. A blood transfusion is often needed, but the patient may be transfused his or her own blood if the blood is stored a few months prior to surgery. Complications — such as the rods coming loose, the spine not fusing or nerve damage — may happen, but they are rare. Usually, it takes one to two months before the patient may return to school or work. How is the front of the chest affected?
The two most common chest abnormalities related to Marfan syndrome involve the sternum or breastbone. Pectus excavatum is a sunken (or excavated) sternum. It develops to varying degrees in many people with Marfan syndrome, as well as in children who are not affected. It may impair the breathing in more severe cases, especially when there are other abnormalities in the spine, heart or lungs. These breastbone abnormalities tend to become noticeable in adulthood. For some people, it may become a cosmetic concern.
There is no brace available to correct pectus excavatum. The only treatment option is surgery. There are often good medical reasons, in addition to cosmetic reasons, to repair a severe pectus excavatum. If needed, surgery should be performed in mid- to late-childhood by a children’s general surgeon.
Surgery consists of raising the deformed sternum and ribs, straightening them and holding them with a metal bar. It requires several days of hospitalization. The success rate is high. The metal bar is removed after 4-6 months in a brief outpatient procedure. Afterward, the sternum will look much improved, although there is usually slight residual abnormal chest shape that cannot be fixed completely without taking undue risks. In a few cases, the deformity may recur if it is corrected early in life.
In pectus carinatum, there is a protrusion of the sternum outward. Some people with Marfan syndrome have a pectus excavatum on one side of the chest and a protrusion on the other. Pectus carinatum does not cause compression of the heart or lungs, but may still be cosmetically displeasing to a child or teenager. Sometimes a brace can effectively push inward on the sternum to change its outward growth pattern, but this is not used often. Surgery is another option.
Rotation of the ribs is a side effect of scoliosis. The ribs on the side of the curve usually protrude farther in the back. If spine surgery is done, the ribs often straighten out. Rarely, an operation on the ribs themselves is needed.
How are the feet of someone with Marfan syndrome affected?
People with Marfan syndrome have feet that are long and slender. The shape of the foot varies, but in most affected people, the arch is flatter than normal. In others, the arch is higher than normal. Treatment is not usually required. An arch support cannot make a flat foot develop an arch, but it may improve the gait or lessen discomfort.
Foot pain is sometimes a problem for people with Marfan syndrome. This is due to the stresses of a large frame on the flexible feet. Special cushions, inserts or orthotics may help. Wearing shoes with low heels, or no heels, is recommended. The key is to try different shoe styles to find one that is comfortable. Foot surgery is rarely needed. Surgery should be undertaken only after careful trials of non-operative treatments.
People with Marfan syndrome may also have curled toes (claw toes or hammer toes). Wearing tight shoes can make this worse.
What are some other orthopedic concerns of Marfan syndrome?
Marfan syndrome is thought of as a condition of loose ligaments. Yet dislocation or sprain of major joints (shoulder, knee, ankle) seem no more common than in the general population. One reason may be that people with Marfan syndrome limit themselves from intense physical activity or twisting exercises in order to avoid stress on the heart or aorta. Another probable reason is that the major ligaments in their joints are not weak; they are just a little loose.
People with Marfan syndrome may have more aches in the back and limbs than other people. This may have something to do with the mechanics of living in a large body, with all of the attendant stresses, along with the laxity of the joints. Aches can be treated with heat, an over-the-counter analgesic (such as Tylenol®) and modification of activities. The chance of a return to normal function, with these treatments, is excellent. Other problems may include:
Kyphosis (hunched back)
This is a curve best seen from the side. It is normal to have a kyphosis of up to 50º. However, increasing curves can cause deformity or back ache in some people. Kyphosis does not usually lead to a decrease in pulmonary function. Kyphosis in people with Marfan syndrome may occur in the thoracic (upper) spine or in the lumbar (lower) spine.
The treatment for kyphosis is similar to the treatment for scoliosis. In the growing child, the brace is often effective. In the older patient or in someone with more severe kyphosis, the brace does not help. Therefore, the patient should try exercises to keep the back free of pain. If satisfaction is not achieved, surgery is an option. It is done in almost the same way as scoliosis surgery, although it is less commonly needed. People with kyphosis should be careful to maintain good calcium intake and a mild exercise program to prevent osteoporosis, which may make the kyphosis worse.
Spondylolisthesis
This refers to a slip forward of one vertebra upon the one below it. This usually happens near the lower end of the spine. It can occur in anyone, but the forward slipping is more common in people with Marfan syndrome. Someone with this condition usually has a low back ache or stiffness and is unable to bend forward to touch the toes. Usually there is no neurologic damage, except in very severe cases. Treatment involves exercise or bracing for the mild cases, or surgery if the slipping becomes greater than 30 percent.
Dural ectasia
A finding more unique to Marfan syndrome is swelling or ectasia of the spinal cord sac (dura). This occurs because the spinal cord sac cannot withstand the pressure of the spinal fluid. If swelling occurs, it is frequently in the lower part of the lumbar or sacral spine. Sometimes, the enlarged sac will actually press into adjacent spaces, such as the pelvis.
Symptoms of dural ectasia include low back ache and a burning sensation, numbness or weakness in the legs. The symptoms resemble any back ache; however, enlarged dura can be seen on magnetic resonance imaging (MRI) or computed tomography (CT). For treatment, spinal shunting or medication may help in severe cases. It is best to leave mild cases alone. More information can be found under Dural Ectasia.
Protrusio Acetabulae
In some people with Marfan syndrome, the hip sockets become deep during growth. This is called protrusio acetabulae. The acetabulum is the socket of the hip joint. The cause of this condition is not known. It does not cause problems or symptoms in childhood. In adulthood, the deepened sockets can lead to earlier arthritic change, which is noted with aching in the hips or groin. Some people with this diagnosis need to have artificial hips in middle age or later. This affects less than five percent of people with Marfan syndrome.
For additional resources on orthopedic related issues, see the "Heart of the Matter" plain language fact sheet library.
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