A B C D E F G H I J K L M N O P R S T U V W

SLIPPED FEMORAL EPIPHYSIS

What is a Slipped Femoral Epiphysis ?

The femoral epiphysis is the ball of the hip joint in a child. In this condition, the epiphysis remains in its normal position within the hip socket. However, where the epiphysis joins on to the upper part of the thigh bone (or femur) a weakness in this join allows the affected leg to turn outwards. Children between the ages of 10 and 16 may suffer from this condition which is rather more common in boys than girls. A slip usually occurs slowly (chronic). In this case the child may complain of pain in the groin with exercise or sporting activity. The pain may settle with rest but is normally accompanied by a limp. Less commonly a limp or odd walk may be the only abnormality present. A few children only complain of pain in the knee. This is due to the fact that the same nerves supply both the hip and the knee. If symptoms have been present for some time, the affected leg will be turned outwards, and shortening of the leg may also be present. Sometimes there is a sudden increase in the slip after a period of gradual slipping (acute on chronic). Pain is then more severe and the child will have difficulty walking. More rarely, the slip occurs suddenly (acute). In this case the child is in severe pain and is quite unable to walk. In about one case in three, both hips are affected.

How does a Slipped Femoral Epiphysis occur ?

A slip occurs because the join (or growth plate) between the epiphysis and the rest of the thigh bone cannot stand up to the stress placed upon it. It is particularly vulnerable during the rapid growth of adolescence. A minor fall may cause acute, or acute on chronic slipping.

Why does a Slipped Femoral Epiphysis occur ?

The thickness of the growth plate is affected by various hormones. There is normally a balance between sex hormones and growth hormones. A change in hormone balance may occur during the adolescent growth spurt, particularly if puberty is delayed. Obesity and an underactive thyroid gland also predispose a child to this condition. Once growth of the child ceases, the join fuses and the condition is halted.

Treatment involved for a Slipped Femoral Epiphysis

A child with a slipped epiphysis is admitted to hospital straight away. Traction with weights pulling on Elastoplast tapes stuck onto the leg is usually used initially but surgery is almost always necessary. The type of operation depends both on the amount of slip and the speed of onset. In most cases the epiphysis can be pinned in the slipped position. This is a comparatively minor procedure. Insertion of pins between the epiphysis and the thigh bone prevents further slipping and tends to cause the growth plate to fuse. If a very acute major slip occurs, then it is sometimes necessary to replace the epiphysis in position: pinning is carried out in addition. This is a more major procedure. If severe deformity has occurred due to chronic slipping, a realignment operation (osteotomy) may be carried out. All surgery is performed under a general anaesthetic. Pinning requires only one or two small incisions on the upper thigh. Recovery afterwards is rapid, and walking is allowed partially weight bearing with crutches. Hospital stay is about 3 to 4 days. Crutches are usually required for 4 to 6 weeks. Open repositioning of the epiphysis or osteotomy requires a longer incision on the side of the thigh. Hospital stay is usually at least 2 weeks in this case. Crutches are then required for up to 3 months.

During treatment for a Slipped Femoral Epiphysis

General complications of surgery are rare in children. Infection of the wound occurs occasionally. The position of the pins may not be ideal, particularly if there is a major slip. This may result in persisting pain. Re-operation is sometimes necessary. Normally pain, limp and turning out of the leg rapidly settle after pinning. Visits to the specialist and x-rays are needed at regular intervals until growth ceases. Following this, the pins are removed. Early medical advice should be sought if any pain or a limp affects the opposite leg. If your child is very young at the time of treatment, the capital epiphysis can grow off the pin. This should normally be picked up during routine follow-up. If not, then the child may experience a return of symptoms. Replacement of the pins with longer ones is necessary in this situation. After a major acute slip, the bone of the epiphysis may be deprived of its blood supply (avascular necrosis). Persisting pain and stiffness accompany this complication and early arthritis commonly follows. Damage to the cartilage of the joint surfaces can also occur. This is also associated with major slips and surgical replacement of the epiphysis. Stiffness is the main result of this complication, and early arthritis usually follows. There is an increased risk of degenerative arthritis in later life following this condition. However, it usually only occurs following complications, or when there has been a large degree of slip.

If a Slipped Femoral Epiphysis is left untreated

Untreated, the slip is likely to progress and produce severe deformity. An acute major slip may occur with an increased risk of serious complications. Early diagnosis and treatment of this condition is extremely important. Any symptoms occurring in the opposite hip following treatment should be investigated urgently.