Legg–Calvé–Perthes disease (LCPD) is a childhood hip disorder initiated by a disruption of blood flow to the head of the femur.
Due to the lack of blood flow, osteonecrosis or avascular necrosis occurs and stops growth.
Over time, healing occurs by new blood vessels infiltrating the dead bone and removing the necrotic bone which leads to a loss of bone mass and a weakening of the femoral head.
Symptoms include: Pain in the hip, knee, ankle or groin.
Patients often display uneven gait and limited range of motion, and they experience mild to severe pain in the groin area.
Pain is exacerbated by hip or leg movement, especially internal hip rotation, twisting the lower leg away from the center of the body.
The range of motion is reduced, particularly in abduction and internal rotation,.
Patients presents with a limp.
Pain is usually mild.
It is a form of osteochondrosis, characterized by the temporary loss of blood supply to the femoral head, which can result in the bones of the hip joint being damaged and eventually collapsing.
The exact cause of LCPD is unknown, but it is believed to involve a combination of genetics and environmental factors.
Usual onset age 4 to 8 years, but it can occur in children between the ages of 2 and 15.
It is generally diagnosed between 5 and 12 years of age, although it has been diagnosed as early as 18 months.
Cause by the artery of the ligmentum teres femoris being constricted or even blocked too early, not allowing for time when the medial circumflex femoral artery takes over.
The medial circumflex femoral artery is the principal source of blood supply to the femoral head.
Frequency is 1/1200.
It produces a permanent deformity of the femoral head, which increases the risk of developing osteoarthritis in adults.
A form of osteochondritis which affects only the hip.
Both hips should always be investigated to rule out multiple epiphyseal dysplasia.
Thigh muscle atrophy may occur from disuse and an inequality of leg length may appear.
Activity can cause severe irritation or inflammation of the damaged area, including standing, walking, running, kneeling, or stooping repeatedly for an extended period of time.
It is predominantly a disease of boys (4:1 ratio).
It effects mostly male children of Caucasian descent.
Bilateral Perthes is seen in about 10% of children diagnosed.
LCPD factors include: heredity, trauma, endocrine dysfunction, inflammation, nutrition, altered circulatory hemodynamics, impaired and disproportionate growth, low birth weight, delayed skeletal maturity, short stature, systemic hormonal changes, and low economic index.
With time, healing occurs by new blood vessels infiltrating the dead bone.
The necrotic bone is removed leading to a loss of bone mass and a weakening of the femoral head, some degree of collapse and deformity of the femoral head.
Sometimes there are secondary changes to the shape of the hip socket.
It can produce a permanent deformity of the femoral head, which increases the risk of developing osteoarthritis in adults.
Diagnosis:
X-rays of the hip may suggest the diagnosis.
X-rays usually demonstrate a flattened, and later fragmented, femoral head.
A bone scan or MRI may be useful in making the diagnosis in those cases where X-rays are inconclusive.
MRI is more accurate,at 97–99% against 88–93% in plain radiography for diagnosis.
Treatment:
Goals of treatment are to decrease pain, reduce the loss of hip motion, and prevent or minimize permanent femoral head deformity so that the risk of developing a severe degenerative arthritis as adult can be reduced
Younger children have a better prognosis than older children.
Treatment: removes mechanical pressure from the joint until the disease has run its course.
Treatments options include traction to separate the femur from the pelvis and reduce wear, braces to restore range of motion, physiotherapy, and surgical intervention when necessary because of permanent joint damage.
Custom orthotics may be used.
Overnight traction may be used.
Walking devices internally rotate the femoral head and abduct the leg(s) at 45°.
Orthoses can start as proximal as the lumbar spine, and extend the length of the limbs to the floor.
Many children, especially those with the onset of the disease before age 6, need no intervention and refrain from contact sports or games which impact the hip.
Current treatment options for older children over age 8 include prolonged periods without weight bearing, osteotomies=femoral, pelvic, or shelf, and the hip distraction method using an external fixator which relieves the hip from carrying the body’s weight.
Running and high-impact sports are not recommended during treatment for Perthes disease.
Children can remain active through a variety of other activities that limit mechanical stress on the hip joint.
Swimming allows exercise of the hip muscles with full range of motion while reducing the stress to a minimum.
Cycling keeps stress to a minimum.
Physiotherapy generally involves a series of daily exercises, focusing on improving and maintaining a full range of motion of the femur within the hip socket to ensure that the femur and hip socket have a perfectly smooth interface.
Physiotherapy will minimize the long-term effects of the disease.
Perthes disease is self-limiting.
If the head of femur is left deformed, long-term problems can occur.
Treatment is aimed at minimizing damage.
It is recommended not to use steroids or alcohol as these reduce oxygen in the blood which is needed in the joint.
Problems in the knee and back can arise secondary to abnormal posture and stride adopted to protect the affected joint.
The condition is also linked to arthritis of the hip, and hip replacements are relatively common as the already damaged hip experiences routine wear.
Children younger than six have the best prognosis, since they have time for the dead bone to revascularize and remodel, with a good chance that the femoral head will recover and remain spherical after resolution of the disease.
Children who have been diagnosed with Perthes’ disease after the age of ten are at a very high risk of developing osteoarthritis and coxa magna.
When an LCP disease diagnosis occurs after age eight, a better outcome results with surgery rather than nonoperative treatments.
Shape of femoral head at the time when Legg-Calvé Perthes disease heals is the most important determinant of risk for degenerative arthritis.
Perthes’ disease is one of the most common hip disorders in young children, occurring in roughly 5.5 of 100,000 children per year.
The lifetime risk of a child developing the disease is about one per 1,200 individuals.
Boys are affected about three to five times more often than girls.
New cases of Perthes’ disease rarely occur after age 14 years.
White northern Europeans appear to be affected more frequently than other ethnicities.
Children of those with the disease themselves may have a very slightly increased risk, though it is unclear if this is because of a genetic predisposition, or a shared environmental factor.
It is most commonly seen in persons aged three to twelve years, with a median of six years of age.
There is a low incidence rate in London, and a progressive increase in disease in more northerly areas with maximal in Scotland.
More socioeconomically deprived communities may have a greater risk of disease, considered to be related tobacco smoke exposure.