Femoral head osteonecrosis

Femoral head osteonecrosis, operative treatment with autologous mesenchymal stem cells


Hip X-ray, femoral head osteonecrosis bilaterally


Femoral head osteonecrosis


MRI.  Femoral head osteonecrosis bilaterally


Hip MRI, femoral head osteonecrosis bilaterally

The osteonecrosis or avascular necrosis of the femoral head is a pathological condition where the blood supply is stopped in this subchondral bone resulting in the death of osteocytes and precipitating the articular surface.

The phenomenon of ischemic femoral head substantially disrupts the normal structure of cancellous bone, which in turn loses its supporting ability and subsides creating permanent deformation of the joint and premature osteoarthritis.
The disease occurs in young patients aged 35-45 years with triple incidence in men compared to women.

The factors that have been associated with the disease are divided in traumatic and non-traumatic.

In traumatic factors are:
 
hip trauma
the foregoing surgery on it,
the sliding of the femoral epiphyseal head in childhood.

In non-trauma agents include:
 
chronic use of corticosteroids,
alcoholism,
diving,
systemic lupus erythematosus,
sickle cell anemia,
hyperlipidemia (high cholesterol),
the existence of thrombophilia (heterozygous or homozygous) disease which patients largely unaware that they have.

Many times there may be identification of the cause of the disease is called idiopathic osteonecrosis. The pathogenetic mechanism leading to the disruption of the blood supply in these cases is multifactorial.

Adequate blood supply to an anatomical region is essential for the viability and function in the majority of body tissues.

Without the provision of adequate blood hypoxia conditions generated in the cells, lack of nutrient supply to them, accumulation of metabolic products, thus stopping the biochemical signaling mechanism, ultimately affecting cellular homeostasis total area.

The interruption of blood supply may be because:

1. the direct injury of nutrients arteries of the femoral head,
2. the clots inside arteries,
3. extrinsic compression of blood vessels from swelling of the surrounding elements (increased presence of fatty or other cellular elements in the bone of the femoral head).

Clinically, the patient can report pain in the groin or in the internal - anterior surface of the femur. Rarely can the pain be reflected in the ipsilateral buttock or even the ipsilateral knee.

Symptoms usually worsen with fatigue and decreases with rest. Most often there is a limitation in the motion of the hip joint especially in internal rotation and abduction.

Routine laboratory blood tests shows no pathological evidence but further research may demonstrate thrombophilia or systemic lupus erythematosus.

MRI is the method of choice for clear diagnostic assessment of the disease. The simple radiological examination more often than not brings out the damage in the initial stages leading to underestimation of the clinical status of the patient.

OPERATIVE TREATMENT
THERAPY: 

OPERATIVE TREATMENT

Decompression of the femoral head can be achieved by surgically removing a core of bone.  This reduces intramedullary pressure and thereby prevents further vascular impingement and allows for new bone formation.

Biologic augmentation after core decompression has been attempted with demineralized bone matrix and bone morphogenetic protein.
However, the relative insufficiency of osteoprogenitor cells in the proximal femur of osteonecrotic hips has led to the use of bone marrow stem cells through a single hole drilled into the necrotic area in patients with atraumatic osteonecrosis.

Mesenchymal stem cells have the potential to differentiate into chondrocyte, osteoblasts, fibroblasts, marrow stroma and other tissues of mesenchymal origins. MSCs maintain the ability of mitotic multiplication without significant loss of their specific biomolecular characteristics over extensive population expansion and are capable of differentiating into multiple mesenchymal phenotypes.

The mesenchymal stem cells (MSCs), the non-hematopoietic progenitor cells, are multipotent stem cells from a variety of tissues with the capability of self-renewal, proliferation, differentiation into multi-lineage cell types, as well as anti-inflammatory and immunomodulatory.  These properties make MSCs an ideal source of cell therapy in bone and joint disease.

METHOD

Briefly, bone marrow aspirates (100ml) were harvested from the posterior iliac crest and cultured for 3-5 weeks.

After this period of time surgical exposure of the proximal femur, a bone plug was removed using special drills.  In this hole we put the autologous stem cells with special material.

Under C-arm the special drill is inserted in the femoral head and remove osseous part of the core for the decompression

Autologous stem cells insertion in the remaining hole.

CONCLUSION

Stem cells -based gene therapy is clinically relevant.  Successful treatment of precollapse osteonecrosis of the femoral head could preserve the hip and avoid total hip replacement.

The method also can used in the treatment of many others musculosceletal disorders, inluding genetic disorders, bone tumors, bone defects, fractures, and osteolysis.