| SCOLIOSIS |
| Scoliosis means an unnatural sideways or twisting curvature of the spine. It can occur in children for a variety of reasons. In muscular dystrophy and some of the other neuromuscular disorders scoliosis often develops because the weakened spinal muscles are unable to support the spinal column in the upright position, either standing or sitting. How does scoliosis develop? In young children with muscle weakness spinal curvature may begin very early in life, often soon after the child begins to be supported in the sitting position. This may happen, for example, in relatively severe spinal muscular atrophy (type 2 SMA) and in some of the congenital myopathies, especially congenital muscular dystrophy (CMD). In milder (type 3) SMA scoliosis may begin while the child is walking quite strongly and may gradually increase, eventually becoming a factor in making walking difficult or impossible. Alternatively the scoliosis may appear only after walking becomes impossible. In boys who have Duchenne muscular dystrophy (Dmd) scoliosis often develops soon after they become unable to walk. This is usually between the 8th and 12th year. As the boy gets older and less mobile, spending much of the time sitting, the spinal curve tends to increase. If he usually lies on one particular side in bed, he will tend to develop a spinal curvature which is convex (bent outwards) to that side. Eventually these mobile curves may become fixed and cannot then be fully corrected by any form of treatment. The effects The effect of the scoliosis is two-fold. As time goes on (whether or not the muscle weakness progresses) and as the scoliosis increases, there is progressive tilting of the pelvis (pelvic obliquity). This results in increasing difficulty in sitting as the weight is no longer distributed evenly between the buttocks. The arms may need to be used to support the body on the arm rests of a chair. The other problem is that scoliosis often results in an alteration of the shape of the chest, eventually restricting the capacity of the lungs and so breathing becomes more difficult. It is very important to delay the onset and slow the deterioration of a progressive scoliosis so that the chest remains an efficient breathing machine, sitting remains comfortable and the arms are as free as possible to move. What can be done? Firstly, it is important to keep children who are able to walk mobile and to delay the sitting stage for as long as possible. Those whose walking is quite strong, but who have an increasing scoliosis (an uncommon situation), may benefit from wearing a plastic spinal support called a brace. But if walking is very difficult a brace may make it more so. An operation may then be the best solution. For young children who are unable to walk a spinal brace may be recommended to delay the progress of a curve that is not severe, i.e. measures less than 20-40�, based upon X-rays taken when the child is erect. The brace is unlikely to completely prevent such a curve from progressing; in the long run only an operation can do that. But the brace is used while the child is very young because it may be desirable to allow time for growth of the spine before recommending a spinal operation. If the child is sufficiently well grown, or if the curve is progressing quickly it is usually wise to undertake an operation to correct the scoliosis and stabilise the spine. When should surgical correction be considered? Early childhood SMA and Congenital Myopathy It is not usually necessary to consider surgery in very young children when years of rapid spinal growth lie ahead unless the deformity is severe. With milder curves at this stage bracing is generally the best solution. In later childhood or the teenage years surgery is usually advised if the curve is increasing and the child's health (and especially respiratory function) is sufficiently good. Duchenne md and later onset SMA (Kugelberg-Welander syndrome) When the child is no longer on his feet, the scoliosis may start to progress and can become a problem. Research has shown that a curve that reaches 20� in such circumstances is likely to progress further and many surgeons recommend an operation at this stage to prevent deterioration. It is sensible to consider surgical correction as soon as it becomes evident that the scoliosis is going to lead to postural problems and eventual respiratory impairment. If this is delayed until too late a stage in Dmd the operation becomes more difficult and the individual is more likely to experience difficulties with anaesthetics because of problems with lung function and with the effect of anaesthetic agents on his heart. The right time to undertake surgery needs to be decided in consultation between the young person, the surgeon, the paediatrician and the family. The operation The use of metal rods inserted alongside the vertebral column and secured by wires has considerably improved the management of children with scoliosis due to a neuromuscular condition. Dr Edwardo Luque from Mexico introduced this method for correcting spinal deformity. The operation consists of exposing the spinal column, placing specially contoured long metal rods on either side of the vertebrae extending from the pelvis up to the upper part of the chest, then placing wires under each lamina (the arch-like part of each vertebra) and straightening the spine as much as possible. Surgical fusion (fixation) of the joints in the spine is also done to reinforce the spinal stability. Around the world, this technique ("the Luque procedure") has provided really useful results when applied to neuromuscular scoliosis. It gives sound fixation to the spine, eliminating the need for braces to be worn and allowing the child to sit upright. However, there are other alternatives and more up-to-date operations, based on the same principles, which are used in some centres depending on the type of curve and its severity. What are the risks? There are risks from these operations. The risk of anaesthesia is clearly a problem and requires skilled anaesthetic advice. The operation itself is technically demanding and should be carried out by an experienced spinal surgeon. Neurological complications can occur with impaired function of the spinal cord during the operation. Prior to this major surgery, each child needs to undergo a full assessment by the medical team to evaluate the risks involved. Spinal cord monitoring is performed during the operation and greatly reduces the risk of damage. The results By improving the shape of the spinal column and preventing collapse of the spine, a successful operation will benefit the child's posture, eliminate the need for a brace and will also sometimes improve respiratory function, or at least delay its deterioration. Being able to remain sitting in an upright position is an invaluable asset. The child's head remains balanced over the pelvis and he/she can sit comfortably in a chair, eliminating the need for padding or braces to support the collapsing spine. MORE ABOUT SCOLIOSIS ON THE NEXT PAGE-> |