The etiology and pathogenesis of osteopathy is in many respects the same as those of trauma, but there are also some differences.

Etiology of osteopathy

Endogenous pathogenic factors

Congenital aplasia    Many congenital deformities in children are caused by congenital aplasia. Some of these deformities may be found at birth, such as congenital talipes equino varus. Some appear later in youth, such as congenital scoliosis. Some bone tumors, such as multiple exostosis are related to genetic factors in pathogenesis.
    
Age    There are different morbidities of bone and tendon diseases in different age periods. For example, poliomyelitis often occurs in infants and young children, osteochondrosis in young people, osteoarticular retrograde degeneration in middle-aged or old people.
       
Constitution    Young and vigorous people with sound kidney qi and strong tendon and bones are not subject to tendon and bone diseases. If the constitution is weak, the liver and kidney are insufficient and the healthy qi is impaired, pathogens will take advantage of deficiency and invade the body, resulting in bone tuberculosis or bone carbuncle.
      
Nutritive condition    Dystrophy may cause such metabolic osteopathies as rickets, osteomalacia, and osteoporosis.
     
Visceral dysfunction    Tendon and bone are the external matches of the liver and the kidney. When visceral functions get disordered, the tendon and bone will lose their nourishment, hence disease, such as renal osteopathy, dysparathyroidism, hormonal bone necrosis, cerebral palsy, and neurogenic myophagism.
  
Exogenous pathogenic factors

Invasion of six exogenous pathogenic factors    Invasion of such six exogenous pathogenic factors as wind, cold and dampness may cause Bi-syndromes of tendon and bone.
    
Infection of pathogen    Invasion of various pathogens such as bacteria and viruses may cause infectious diseases of tendon and bone and poliomyelitis.
    
Chronic strain    It may cause various diseases of tendon and bone, such as retrograde articular degeneration and some occupation diseases.
    
Geographic factors    In different regions, the geographic conditions, climatic factors and dietary habits are different, and there are different common diseases. For example, some osteophathies like osteoarthrosis deformans endemica and fluorosis of bone are related to these factors.
 

Poison and radioactive rays    Constant exposure to harmful substances like inorganic poisons (lead, zinc, phosphorus and chromium) and organic, poisons (benzene, chlorine and ethylene), and radioactive rays may cause injury of bone.

Pathogenesis of osteopathy

Pathogenesis of exogenous pathogens

Pathogenic wind changing    Many diseases are caused by pathogenic wind. Fight between healthy qi and pathogenic factors around the joint leads to flaccidity of tendon and migratory pain.
   
Pathogenic cold resulting in pain    Affection by pathogenic cold makes yang qi damage, thus, yang qi fails to warm the tendons, which then contract, resulting in pain.
     
Pathogenic fire damaging yin   Fire and heat can damage yin and consume blood, leading to malnutrition of tendon and bone with resultant atrophy and blockage syndrome. Or if the muscle is putrefied by rampant heat, it will cause purulent sore. Or if the rampant heat stagnates, it will lead to formation of tumor.
  
Pathogenesis of qi and blood

Qi stagnation    If the flow of qi is blocked, it will result in pain, which is characteristic of migratory and distending nature.
      
Blood stasis    If meridians are blocked by stagnant blood, it will result in pain, which is fixed in certain focus and is of stabbing or cutting nature.

Qi deficiency    Because of congenitally inadequate essence qi in the kidney and insufficient grain qi derived from food and water after birth by the spleen and stomach, as a result, viscera, tendons and bones become asthenic. Then there may occur shortness of breath, reluctance to talk, lassitude, hyperpnea, spontaneous sweating, thready, weak and forceless pulse.
      
Blood deficiency    It may be caused by the failure of the spleen and stomach to produce enough blood or by massive bleeding. Besides the symptoms of pale complexion, palpitation, shortness of breath, numbness of the limbs, vexation, insomnia, and thready and forceless pulse, there may occur contracture of tendon and ankylosis.
  
Pathogenesis of meridians

Meridians are passages, through which qi and blood circulate and by which viscera are interrelated. The upper and the lower, the interior and the exterior parts of the body are communicated, and functions of every part of the body are regulated. Life activity of the human body, occurrence of diseases and effect of treatment are all dependent upon meridians. So, if the disease of tendon and bone involves a meridian, it will affect the function of organs through which the meridian runs, resulting in symptoms in the corresponding parts of the body. For example, myelopathy or diseases of peripheral nerve may cause paralysis.
  
Pathogenesis of viscera

Osteopathy is most closely related to the kidney, liver and spleen.
    
The kidney dominates bones, produces marrow and stores essence    The growth, development and repair of bone are all dependent upon the nourishment of the kidney essence. So, maldevelopment of bone in children is often caused by congenital deficiency of kidney essence. As a person is in his old age, his kidney essence is also declined and fails to nourish bone, then there may occur hyperosteogeny and osteoporosis. Development of bone tumor is closely related to the kidney.
    
The liver dominates tendons and stores blood    The liver has the function of storing blood and regulating blood volume. If the liver is short of blood and fails to nourish tendons, it will give rise to contracture of tendons, numbness and impaired movement of the limbs.
    
The spleen dominates muscles and four extremities    The spleen transforms the foodstuffs into essential substances and transports the nutritive essence to nourish the four extremities and bones. If the spleen fails in transformation and transportation, the essential substances will be short, then there may occur atrophy of muscle with no strength in movement. In addition, the diseases of tendon and bone are also difficult to be cured.