Legg-Calvet-Perthes disease

Leggy-Calve-Perthes disease (or osteochondrosis of the head of the femur) is the most common type of aseptic necrosis of the femoral head in childhood. Until now, the disease leads to severe violations of the anatomical structure and function of the hip joint, and consequently, to the disability of patients. As an independent disease, Perthes' disease was discovered only at the beginning of the last century, before that it was considered bone tuberculosis. Among the diseases of the hip joint in childhood, it is met in 25.3% of children.

Perthes' disease has a different degree of severity, which is determined mainly by the size, location of the focus of necrosis (the so-called sequestration) in the epiphysis and the age of the child at the time of onset of the disease.

[1], [2], [3]

Causes of the legg-Calvet-Perthes disease

The causes and pathogenesis of Legg-Calvet-Perthes disease have not been fully elucidated. According to recent studies, predisposing factors of Perthes' disease are congenital dysplasia of the spinal cord and physiological restructuring of the regional vascular system.

Congenital dysplasia of the spinal cord (at the level of the inferior thoracic and upper lumbar segments) of varying severity determines the violation of the innervation of the lower extremities. As a result, anatomical and functional changes in the vascular system occur in the region of the hip joints. Anatomical changes consist in hypoplasia of all vessels feeding the joint, and a small number of anastomoses between them. Functional disorders - spasm of the arteries due to increased sympathetic system influence and reflex dilatation of veins. They lead to a decrease in arterial influx, difficulty in venous outflow and to latent ischemia of the bone tissue of the head and neck of the thigh.

Physiological reorganization of the vascular system of the epiphysis of the femoral head from the puerile type of blood supply to the adult type significantly increases the likelihood of development of blood flow disorders.

Functional overload, microdamage, trauma, hypothermia and infection are the factors that lead to decompensation of the blood supply to the femoral head, the transition of bone tissue ischemia to its necrosis and the clinical onset of the disease.

[4], [5],

Symptoms of the legg-Calvet-Perthes disease

Early symptoms of Perthes disease - a characteristic pain syndrome and associated sparing lameness and limitation of the amplitude of movements in the joint.

Pain, as a rule, has a periodic character and a different degree of severity. Most often, they are localized in the region of the hip or knee joint, and also along the hip. Sometimes a child can not rely on a sore leg for several days, which is why he is in bed, but often walks, limping. Lameness can be weakly expressed in the form of a foot dragging and lasts from several days to several weeks.

Periods of clinical manifestations usually alternate with periods of remission. In some cases, there is no pain syndrome at all.

Diagnostics of the legg-Calvet-Perthes disease

On examination, a slight external-rotational contracture and hypotrophy of the muscles of the lower limb are noted. As a rule, the abduction and internal rotation of the thigh are limited and painful. Often, clinical signs of spondylomyelodysplasia of the lumbosacral spine are revealed, which is more likely to suggest Perthes' disease.

With restriction of lead or internal rotation of the thigh and characteristic anamnestic data, radiography of the hip joints is performed in two projections (anteroposterior projection and the projection of Lauenstein).

Instrumental diagnostic methods

The first radiologic symptoms of the disease are a slight slanting (flattening) of the external lateral part of the affected epiphysis and a depletion of its bone structure with an enlarged X-ray joint slot.

Somewhat later, a symptom of "wet snow" is revealed, consisting in the appearance of heterogeneity of the osseous structure of the epiphysis with areas of increased and decreased optical density and indicating the development of osteonecrosis.

Then follows the stage of the impression fracture, which has a more distinct radiographic pattern and is characterized by a decrease in height and a tightening of the osseous structure of the epiphysis with the loss of its normal architectonics, a symptom of the "Cretaceous epiphysis."

Often, the beginning of the stage of an impression fracture is characterized by the appearance in the affected epiphysis of the line of the subchondral pathological fracture - a symptom of the "nail", according to the localization and extent of which it is possible to predict the size and localization of the potential focus of necrosis - sequester, and consequently, the severity of the disease.

It is considered that the first stage of the disease - the stage of osteonecrosis - is reversible and with a small focus of necrosis, which is rapidly revascularized, it does not go into the stage of an impression fracture. The appearance of a subchondral pathological fracture in the epiphysis indicates the onset of a long, stepwise course of the pathological process, which may last several years.

Recently, for early diagnosis of osteochondropathy of the femoral head, MRI is often used. This method has high sensitivity and specificity. It allows to identify and determine the exact size and localization of the focus of necrosis in the head of the thigh several weeks earlier than it is detected on the roentgenogram.

Sonography also allows early diagnosis of the disease, but in the diagnosis of Perthes disease, it has only an auxiliary value. Sonography determines changes in the acoustic density of the proximal metaepiphysis of the femur and joint effusion. In addition, it helps to trace the dynamics of restoration of the structure of the epiphysis.

The clinical and radiologic picture of Perthes' disease in subsequent stages (impression fracture, fragmentation, recovery and outcome) is typical, and the diagnosis of the disease is not difficult, but the later the diagnosis is established, the worse the forecast for restoring the normal anatomical structure and hip function.

[6], [7]

Treatment of the legg-Calvet-Perthes disease

Patients with osteochondropathy of the femoral head require complex pathogenetic treatment in conditions of complete exclusion of the load on the leg from the moment of diagnosis. In most cases, the treatment is conservative. However, with a large foci of necrosis involving the lateral part of the epiphysis in children aged 6 years and older, it is desirable to perform surgical treatment against conservative measures. This is due to the pronounced deformation of the femoral head and the protracted (torpid) course of the disease. A pronounced deformation of the femoral head, in turn, can cause the formation of an extrusion subluxation in the affected joint.

Necessary conditions for complex pathogenetic treatment:

• Exclusion of compression of the hip joint due to the tension of its capsular-ligament apparatus and the tension of the surrounding muscles, as well as the continuing axial load on the limb;
• changes in the spatial position of the pelvic and / or femoral components of the affected joint (conservative or surgical methods) to completely immerse the femoral head in the acetabulum, creating a degree of bone coverage equal to unity;
• stimulation of recovery processes (revascularization and reoccification) and resorption of necrotic bone tissue in the head of the thigh, freed from compression effects and immersed in the acetabulum.

Conservative treatment

Conservative treatment is carried out under conditions of bed rest, with the affected lower limb attached to the position of retraction and internal rotation, which contributes to the complete immersion of the femoral head into the acetabulum. This position is supported by Mirzoyeva's bus. Gypsum bandage-brace on the knee joints on the Lange, cuff or stick-plaster stretch for the thigh and shin, as well as some other devices that perform a disciplinary function.

The necessary withdrawal and internal rotation in the hip joint, as a rule, is 20-25 °. Mirzoyeva's tie and cuff traction are removed for the period of medical and hygienic measures - usually no more than 6 hours a day. The stretching is carried out round the clock by courses lasting 4-6 weeks, coinciding with the course of physiotherapy, at least 3-4 courses per year.

The advantages of removable devices - the possibility of full-fledged medical gymnastics and physiotherapy procedures. In addition, there is the possibility of limited walking on crutches without the support of a diseased leg or with a dosed load that promotes stimulation of the reparative process in the recovery stage, and the care for the patient is facilitated. However, in the absence of proper control of the child's stay in such adaptations, a plaster bandage in the Lange position is recommended. The ability of the child to move with crutches depends on the age of the patient, the development of coordination of movements and his discipline. The nature of the lesion is also important - one- or two-sided.

Often, the beginning of treatment in the conditions of the centering device is hampered by the chronic sluggish synovitis of the hip joint accompanying Perthes' disease - a painful restriction of the abduction and / or internal rotation of the thigh, and in some cases the formed vicious flexion and reduction position.

In case of inflammation of the affected joint, the medicamentous treatment of NSAIDs - diclofenac and ibuprofen in age dosages and anti-inflammatory physiotherapy - is performed to restore the amplitude of hip movements. The duration of such treatment is usually 2 weeks. In the absence of effect, a tenomiotomy of the contracted subspinal and / or leading hamstrings is performed before applying a cast bandage or a discharge line.

Therapeutic gymnastics is an important part of the treatment and consists of passive and active movements in the hip (flexion, retraction and internal rotation) and knee joints. It continues after reaching the full amplitude of the hip movements. During exercise, the child should not experience severe pain and fatigue.

Physiotherapeutic procedures - electrical stimulation of the gluteus muscles and hip muscles, various types of electrophoresis, impact on the hip joint area with the vibroacoustic device "Vitafon", warm (mineral) mud. Thermal procedures on the hip (hot mud, paraffin and ozocerite) are completely excluded.

Physiotherapy is carried out in conjunction with a massage of the muscles of the hip joints in courses of 8-12 procedures at least 3-4 times per year.

Electrophoresis of angioprotectors on the spine area is combined with electrophoresis of angioprotectors and microelements on the hip joint area, as well as with ingestion of osteo- and chondroprotectors. On the thoracolumbar spine (Th11-12 - L1-2), electrophoresis is made of ganglion blocker azamethonium bromide (pentamine), on the lumbosacral section - aminophylline (euphyllin), on the hip joint region - nicotinic acid. The region of the hip joint is administered with calcium-phosphorus-sulfur electrophoresis, calcium-sulfur-ascorbic acid (according to the tripolar technique) or calcium phosphorus.

Control radiography of hip joints in anteroposterior projection and projection of Lauenstein is performed once every 3-4 months. The question of putting the child on its feet without supporting means is decided upon the completion of the x-ray stage of recovery.

Practically in all cases of the disease in children under 6 years of age, the prognosis with conservative treatment is favorable - a significant potential for bone formation in the affected femoral head and the growth of its cartilaginous model ensures complete restoration of the shape and size of the femoral head (remodeling) in the shape and size of the acetabulum. The duration of conservative treatment at this age is no more than 2-3 years.

[8], [9], [10], [11]

Surgery

Reconstructive and restorative surgical interventions to treat children with Perthes' disease:

• medializing and corrective osteotomy of the hip;
• rotational transposition of the acetabulum, which is performed as an independent intervention, and in combination with medializing osteotomy of the thigh.

Among the varieties of rotational transpositions of the acetabulum, Salter's operation is most in demand.

Surgical intervention is performed in order to center (fully immerse) the femoral head in the acetabulum, reduce the compression effect of the muscles of the hip joint region and stimulate the reparative process.

The high efficiency of remodeling operations in the most severe cases of Perthes' disease - subtotal and total defeat of the epiphysis - is proved by a large clinical experience. Surgical intervention provides a more complete restoration of the shape and size of the femoral head, as well as a significant reduction in the duration of the disease - the patient is put on legs without supporting means on average 12 ± 3 months, depending on the stage of the disease.