RISK FACTORS FOR AVASCULAR NECROSIS (AVN)

 Tampa, Saint Petersburg and Clearwater, Fl

 

AVASCULAR NECROSIS (AVN) DEFINITION

 

AVN is a condition in which the blood supply to a region of bone is disrupted (avascular), rendering the bone without oxygen and nutrition, thus it dies (necrosis).

 

SYNONYMS

 

Avascular Necrosis (AVN)

Osteonecrosis

Ischemic Necrosis

Aseptic Necrosis

Bone infarction  (ischemic event)

Bone infraction (non-displaced fracture)

 

COMMON SITES

 

The most frequent bones affected are the hip, shoulder, knee, wrist (lunate and scaphoid), and ankle/foot (talus,navicular, metatarsals)

 

CLINICAL COURSE

AVN may be stable after the area of necrosis develops. It may progress, or the zone of necrosis may collapse and degenerate the joint. This may develop into a secondary arthritis. Prevention of this course is paramount to preventing joint replacement surgery.

 

RISK FACTORS

Trauma

Idiopathic

Corticosteroids (cortisone)

Alcohol excess

Pancreatitis

Lupus

Rheumatoid Arthritis

Sickle Cell Disease

Gaucher’s (a genetic fat storage disorder)

Caisson’s (decompression sickness or the bends)

Radiation

Chemotherapy

Vasculitis

Embolism

Thrombosis

AIDS

Hypertension

Prolonged exposure to great pressure (commercial or military divers)

 

Trauma that disrupts the blood supply, such as a fracture will have significant ischemia.

Lesser trauma may have a transitory ischemic effect, resulting in lesser degrees of osteonecrosis.

The exact mechanism of other risk factors have basis in theory. Proposed mechanisms in steroids and alcohol use are fatty infiltration of bone, which may impair blood flow resulting in ischemia.

 

AVN MECHANISM FOR REPAIR: STEM CELLS

 

Normal tissue that becomes ischemic or necrotic may have some ability to repair. This is dependent upon the extent of ischemia or necrosis.

Our own bodies stem cells initiate this repair, by the process of angiogenesis, and the formation of new bone growth. Both of these processes are under stem cell control for healing and reparative effect. A natural problem occurs when the zone of ischemia prevents the migration of stem cells, or adjacent stem cells are of insufficient numbers to overcome the area of necrosis. This problem may be countered by injecting the patients own stem cells directly into the area of ischemic necrosis. This process has been utilized for many different joints in an attempt to create healing and prevent secondary arthritis.

 

For additional information on AVN STEM CELL TREATMENT and AVN ATHLETIC INJURIES

 

 

Dr. Dennis Lox serves patients in the greater Tampa Bay area, including, Clearwater, St. Petersburg, Tampa, New Port Richey, Sarasota, Orlando and Spring Hill. He has been pleased to accommodate the needs of patients throughout Florida, the United States, the Western Hemisphere, and Europe, as well. Located in the 33765 and 33765 areas, our offices can be reached at (727) 462-5582 (Clearwater) and (727) 817-1909 (New Port Richey). Call to schedule your visit today.