Femoral cyst

Bone dysplasia in the growth development zone often manifests itself as a solitary or aneurysmal cyst. A femoral cyst is overwhelmingly diagnosed as a juvenile, solitary benign tumor. According to statistics, 30% of SCCs are formed in this zone, since in principle it is typical for it to develop in long tubular bones. The os femoris is considered the largest and longest of all skeletal bones in the body; the femur consists of the body, proximal and distal epiphysis.

A femoral bone cyst is determined at the age of 5 to 15 years, less often in adult patients. The predominant localization is the proximal metaphysis (end) of the femur without going beyond the boundaries of the cartilaginous epiphyseal line. Unlike other degenerative destructive osteopathies, a bone cyst never affects the joint, which is confirmed in 100% of cases by X-ray examination. The cortical tissue in the area of cyst development is significantly thinned, but preserved. A femoral bone cyst can be small - 2-3 centimeters in diameter, but with a long asymptomatic course of the process, the neoplasm can develop to gigantic sizes, up to spreading throughout the bone.

In a clinical sense, a bone cyst of the hip may manifest itself with the following symptoms:

• The onset of cyst development is asymptomatic.
• There are no disturbances in mineral metabolism or blood composition.
• Progressive deformation of the hip is manifested by thickening in the area of cyst growth without shortening of the limb and the bone itself.
• Soft tissues show no signs of atrophy.
• The skin is unchanged.
• A bone cyst of the hip that has developed to gigantic proportions may cause minor transient pain that increases with movement. The range of motion of the lower extremities is not limited, the pain is tolerable.
• The first symptoms may manifest with a pathological fracture caused by a sudden movement, less often - a minor injury or bruise.
• X-ray shows a lesion in the center of the femur with a characteristic coarse honeycomb pattern.
• The cyst has a round regular shape, less often its shape is defined as spindle-shaped or pear-shaped. The contours of the neoplasm are clear, smooth.
• A bone cyst is characterized by a decrease in the cortical layer of bone without signs of pathological destruction and periosteal reaction.

A diagnosed femoral bone cyst is subject to removal. Currently, more than half of patients with ACC or SCC in the femur undergo surgery, which is considered the most effective method of treating tumor-like bone pathologies. Depending on the size of the cyst, its type, age and health of the patient, either resection or excochleation of the damaged bone area is performed, and then the cyst site is filled with allografts. Percutaneous osteosynthesis restores the normal length and function of the femur, the recovery period lasts from one to one and a half years.

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Bone cyst of the femur

The etiology of the femoral bone cyst is not fully clarified and is the subject of ongoing medical discussions. Based on statistical data obtained from embryologists, most orthopedists and surgeons are inclined to believe that it is dysplasia of bone growth sites, in which the normal division of cartilage tissue is disrupted. The abnormal process of differentiation of cartilage cells is perceived by the body as pathological, and macrophages and lymphocytes are included in the work. Enzymatic neutralization of cells "unrecognized" by the body occurs with the participation of the vascular system, while the intensity of the process depends on the age-related features of human physiology. Most often, a femoral bone cyst is determined at the age of 7-13 years, solitary cysts predominate in boys.

This "fight" with undifferentiated tissues of the bone growth zone is confirmed by long-term clinical observations - both radiological and histological. The most typical reaction of the lymphatic system is the formation of cystic cavities for proximal growth areas, including the femur. Both aneurysmal and solitary cysts can form in the femur; statistical data on their frequency are so contradictory that it is impossible to provide them as objective.

Treatment of a femoral bone cyst depends on the duration of the pathology, the size of the cyst, symptoms and the patient's age. In children, a pathological fracture of the femoral neck is quite often a paradoxical way to reduce the cystic cavity and gradually restore bone tissue. Adult patients, in whom a bone cyst is diagnosed extremely rarely and in 99% is aneurysmal, are able to more adequately tolerate surgical treatment; the neoplasm is subject to surgical removal.

General recommendations for the treatment of femoral cysts in children:

• Decompression of a cyst larger than 2 cm. The wall is punctured, the cavity is washed to cleanse the cyst of enzymes and bone decay products, to neutralize the fibrinolysis process.
• Large solitary cysts are punctured several times during six months, every 2-4 weeks, possibly longer. Aneurysmal cysts are punctured several times in a regimen of 7-10 days. The total number of punctures can reach 10-15 procedures.
• The washed cyst cavity can be filled with drugs that have an antiproteolytic effect (contrycal).
• Stabilization of lysosomal membranes and restoration of collagenosis are carried out using corticosteroids.

This method of conservative treatment in case of an uncomplicated process makes it possible to avoid surgery. If the therapy is successful, the first positive signs of tumor reparation are noticeable already in the 2nd month, the duration of complete cyst reparation can reach 12-24 months. In adult patients, conservative therapy often does not give an effect, but, on the contrary, provokes relapses, therefore, they are prescribed surgery to remove a femoral cyst. In addition, the reparative capacity of the skeletal system in adults is much lower than in children, and only surgical treatment can give the desired result. The choice of the surgical method is determined by the surgeon, based on X-ray data and other diagnostic information. It is advisable to completely, radically remove the defecates and parallel plastic surgery - replacing the removed part of the bone with autologous material or alloplastic substances. With successful treatment, full motor activity of the hip joint can be restored after 2-3 years.

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Femoral head cyst

Aneurysmal cysts most often develop in the femur, mainly in girls, in percentage terms to boys – 80/20%. To understand how an aneurysmal cyst of the femoral head is formed, it is necessary to recall the structure of the femur and the role of the head in the supporting and motor functions.

The caput femoris (head) is located in the area of the proximal epiphysis and has a typical joint surface with a small depression (pit) in the middle - fovea capitis ossis femoris. The head and body of the bone are connected by a specific area - the neck of the femur. Like all joints, the caput femoris functions as a kind of lever in the hip joint, helping a person move. Normally, the hip joint should have the form of a hemisphere with the correct concentric insertion of the head of the femur into the acetabulum. The abnormal position of the caput femoris in a child is partially compensated by gait and rotation of the foot (toes inward or outward). In general, the formation of a cyst of the head of the femur, in addition to the main etiological factors, can be influenced by the blood supply system of the joint, which is carried out due to the vessels of the joint capsule and intraosseous vessels located in the metaphysis. Thus, an aneurysmal cyst most often develops due to pathological dysplasia of bone tissue, vascular bed and as a result of impaired blood microcirculation in the metaphysis. A femoral head cyst is not capable of growing into cartilaginous tissue and affecting the epiphysis, which distinguishes it from osteoblastoclastoma, which is related in clinical manifestations.

Developing in the bone tissue of the caput femoris, the cyst may not produce clinically expressed symptoms for a long time. Transient painful sensations are not noticed by the child until the manifestation of a clear sign of destructive bone damage - a pathological fracture.

What are some possible symptoms that indicate the development of a femoral head cyst in a child? •

• Transient pain in the knee.
• Minor pain in the groin.
• Pain in the pelvic area.
• Transient lameness.
• Periodic disturbance of the child's gait (leg turning outward).
• Pathological fracture in the femoral neck area due to minor trauma or a sharp turn of the torso.

Radiographically, the cyst is defined as a swelling of the bone, the cortical layer is significantly thinned, the cyst cavity looks like a rounded elongated formation with calcareous inclusions.

Treatment tactics for detecting a femoral head cyst in a child may vary, but most often surgeons begin with conservative therapy and immobilization of the hip joint with all the resulting recommendations for bone fractures. If a pathological fracture has occurred in the femoral neck area, dynamic monitoring of the cyst development is carried out for 1-1.5 months, which, as a rule, begins to repair. Signs of cyst cavity repair are an indication for further immobilization for 1-2 months, the entire period the condition of the hip joint is monitored using radiography. If control images do not show positive dynamics, the destructive process in the bone progresses, the cyst cavity increases, then surgical treatment is performed. As a rule, marginal or segmental resection of the damaged bone area is carried out within the boundaries of healthy tissues, in parallel, the defect is filled with homotransplants. In surgical treatment of tumor-like formations in the hip area, relapses are rare and are most often associated with technical errors during the operation (incomplete resection of the cyst and damaged tissue). The prognosis for treating a femoral head cyst is favorable, but the recovery period is difficult and long: the patient has to limit movement for a year.

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Femoral neck cyst

A bone cyst as an independent nosological entity is relatively rare, but it is most common among pediatric patients. As for the femoral neck cyst, such cases are isolated, in addition, this pathology in 50% of cases is confused with other tumor-like diseases of the bone system - chondroma, osteoblastoclastoma, lipoma, especially if the cyst leads to a pathological fracture.

Collum ossis femoris (femoral neck) is a part of the proximal epiphysis directed upward, medially, it connects the head of the femur with other structural parts of the hip joint. It is a fairly narrow bone, compressed in the frontal plane and forming an angle with the axis of the femur. The femoral neck is most vulnerable in females, especially during menopause or with pathological osteoporosis, but in children this part of the skeletal system can also be damaged by various osteodystrophic diseases.

The symptoms of developing bone cysts are not specific, which is typical for any type of cyst - ACC or SCC. However, a child or adult may periodically experience the following symptoms:

• Aching pain in the hip joint.
• The pain may intensify with prolonged walking or, in children, after active sports.
• The patient, completely unconsciously, tries to regularly lean on objects (chair, table) while standing.
• Gait may be affected.
• The X-ray image clearly shows a cavity that occupies almost the entire length of the femoral neck, with normal visual indicators for the rest of the hip joint.
• The cyst cavity can reach large sizes and interfere with leg movements (limited range of motion).
• A bone cyst often causes temporary knee pain.
• A long-term developing cyst and its aggressive course provokes significant destruction of bone tissue and a pathological fracture of the femoral neck.

Diagnosis of a bone cyst of the femoral neck is considered difficult, complex, since tumor-like formations in principle do not have characteristic symptoms and signs. Differentiation of cysts is important in terms of choosing treatment tactics, which can be conservative or surgical. X-ray, computed tomography, and ultrasound of the joint help to clarify the diagnosis.

Conservative treatment is indicated if the cyst is not accompanied by a fracture. The hip joint is immobilized, the patient is given complete rest for a long time. If dynamic observation does not show positive results, and the cyst continues to increase, an operation is performed - excochleation of the cystic cavity and parallel plastic surgery of the removed part (autobone, allograft) along the Adams arc or total filling of the defect.

The same actions are indicated for a pathological bone fracture, the cyst is subject to observation and the course of the immobilization process, then, in the absence of positive dynamics, it is removed within the boundaries of healthy tissues. In addition, the choice of surgical method may depend on the plane of the femoral neck fracture - lateral or medial. Medial fractures always occur inside the joint, in the junction of the neck and head of the femur. Lateral (side or trochanteric) are considered extra-articular and are treated more successfully. Bone alloplasty, transplants help to remodel the bone within 1.5-2 years, in children this process occurs faster if all medical recommendations are followed and motor activity is limited.

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Treatment of femoral cyst

Treatment of bone cysts still remains a serious problem, since there are no general standards and algorithms for both conservative therapy and surgical intervention. The principles and tactics of treating a femoral cyst are determined individually depending on the type of tumor - SCC or ACC, the patient's age, the duration of the pathological process and other parameters.

Conservative treatment of cystic tumor of the hip can be used for patients aged 3 to 15 years, also the choice of conservative method depends on the activity of cyst development and histological analysis of the tumor contents. Relapses of the pathology are a direct indication for surgery, which can be performed in the following ways:

• Intraosseous resection of the cyst within healthy tissues with subsequent alloplasty of the defect.
• Marginal resection.
• Segmental resection of the cyst.
• Cryotherapy.
• Curettage of the cyst.

The basis of conservative treatment of femoral cysts is the reduction of abnormal hydrostatic pressure in the cavity using repeated drainage and neutralization of fibrinolysis by introducing drugs into the cyst.

Cyst puncturing is perforation of the cavity with thin needles, such a procedure, carried out in a certain mode (after 2-3 weeks) helps to reduce the tumor and gives hope that the disease will be stopped. If 2-3 punctures do not give the desired result, the cyst in the femur is scraped out, the defect is filled with a transplant. To speed up the process and prevent refracture, more complex bone grafting methods are sometimes used. During treatment, the patient must stay in bed and limit movements as much as possible to reduce the load on the damaged bone. The recovery and rehabilitation process can last up to one and a half years, children recover faster due to a more active ability to reparation.