Complications of fractures and dislocations.
GENERAL COMPLICATIONS: Shock, venous thrombosis and pulmonary embolism, ‘fracture fever’ delirium tremens following alcoholism, accident neurosis, hypostatic pneumonia and tetanus in compound fracture.
LOCAL COMPLICATIONS: These can be classified into
o Recent complication e.g. injury to the neighbouring joint ,nerve, blood vessels, muscles or tendons, organs of the abdomen or thorax and infections in compound fracture’ and
o Late complications e.g. delayed union, non- union, mal-union. joint instability and stiffness.
Joint injury: Dislocation. Subluxation and/or ligamentus injury of the neighboring joint may be associated with the fracture.
Nerve injury: This should be diagnosed at the time of injury to the bone. Usually the lesion is a neuropraxia which heals automatically. Sometimes severe traction on the nerve during injury or during overzealous manipulation may occur.Immediate nerve injuries which are seen with different bone and joint injuries are
o The spinal cord or cauda equine injury in fracture-dislocation of the spine.
o The axillary nerve in shoulder dislocation or fracture neck of the humerus.
o The radial nerve in fracture shaft of the humerus.
o Ulnar, median and/or radial nerve in supracondylar fracture of the humerus.
o Sciatic nerve in posterior dislocation of the hip and subtrochanteric fracture of the femur.
o The common peroneal nerve in fracture of the neck of the fibula.
o Late nerve injury is sometimes seen as a late complication of fracture. The most common example is the “tardy ulnar palsy” in supracondylar fracture of thehumerus which has been malunited with Cubitus Valgus detormity and in fracture of the medial epicondyle of the humerus where the ulnar nerve is involved in callus and gradual injury to the nerve by bony irregularity if anterior transposition of the ulnar nerve has not been performed.
Injury to blood vessels: The blood vessels are likely to be damaged in different fractures and dislocations. Mostly the vessels are either thrombosed or occluded by spasm or oedema. Sometimes they are pressed upon by the displaced fragment and very rarely they are completely divided. Impairment of circulation following fracture or dislocation should be diagnosed as early as possible. If the impairment is due to displaced fragment, prompt reduction of the fracture or dislocation should be called for. Sometimes the impairment of circulation is due to incorrect application of plaster of paris and these cases should be treated by immediate removal of the plaster and bandages till the pulsation of the artery comes back. If these procedures fail to bring about improvement in circulation, there is a place for immediate arteriography with a view to possible excision and grafting. Vascular injury may lead to gangrene in severe cases and late inchaemic contracture of muscles in less severe cases.
Muscle Complications: The adjoining muscle fibres are often torn in fracture. The torn fibres may become adherent to the intact fibres, fractured site or capsule of the neighbouring joint. This may lead to stiffness of the joint and may require lengthy rehabilitation after the fracture has been consolidated. So very attempt should be made to keep the muscles active when the fracture is kept immobilized. Another complication of the muscle following fracture is disuse atrophy. Active movement is again the treatment of this condition.
Tendon Complications: A torn tendon is rare in association with closed fracture. It is seen in fracture of patella where the tendinous expansion of the quadriceps tendon is torn. Late rupture of tendon is sometimes seen in certain fractures e.g. the extensor pollicis longus tendon in fracture of the lower end of the radius and the long head of the biceps in fracture neck of the humerus. Tendinitis is a very rare complication of a fracture and occasionally affects the tibialis posterior tendon following fracture of the medial malleolus.
Injury to viscera: Injury to internal organs are often seen in various fractures of bones lying near to them. Such examples are injury to the urinary bladder and urethra in fracture of the pelvis, rectum in the fracture of the sacrum, lung, liver or spleen in fracture of the ribs and the brain in fracture of the skull.
Infection: This is quite common in compound fracture and a dreadful complication of the fracture. It may give rise to osteomyelitis with formation of sequestrum and sometimes absorption of bone overwhelms leading to disappearance of some part of the bone. However simple may be the infection, non-union may be the sequel. The most dreadful complications of a compound fracture are the gangrene and tetanus.
Delayed union: The students must have clear conception about what is mean by the term “delayed union”. When a fracture takes an unduly longer time than is expected for union of the particular fracture, the term ‘delayed union’ is used.
The causes are –
o Inadequate immobilization
o Internal fixation which always delays union as the haematoma between the fracture ends which acts as a scaffold for union is disturbed and because the periosteum is stripped off and
o Intact fellow bone- when one bone of the forearm or the leg remains unbroken, the fractured bone always takes longer time for union.
Non-Union: the term “non-union” means bony union of the fracture is not possible without operative intervention. The fragments are joined by fibrous tissue. To know whether the fracture concerned is a case of delayed union or non-union, X-ray is very much essential. In non-union there will be presence of sclerosis at the bone ends and a gap between them.
Causes of non-union are-
o Interpositon of soft tissue either periosteum or muscle between the bone ends
o Inadequate blood supply e.g. fracture of lower half of tibia
o wide separation of fragments e.g. fracture of patella, fracture of the olecranon process or excessive traction
o Inadequate treatment of delayed union that means adequate immobilization for a long period was not maintained in a case of delayed union.
Mal-union: This means union of fragments in a defective position. The commonest deformity is angulation, besides this there may be overlapping with shortening and mal-rotation.
The causes of mal-union are:
Fracture was not reduced properly
After reduction redisplacement occurs within the plaster, for this a check X-ray after a week is advisable in certain fractures anticipating redisplacement, e.g. fracture of both bones of the forearm.
Growth disturbance due to injury to the epiphyseal cartilage may lead to mal-union. Fracture-separation of an epiphysis does not lead to growth disturbance as the fracture occurs through the metaphyseal plate keeping the epiphyseal cartilage intact.
Sites or mal-union are those where the bone is cancellous so union occurs as a rule, but mal-union complicates due to imperfect position of the bone ends. These sites are fracture neck and the supracondylar fracture of the humerus, Colles’ fracture, fracture through the condyles of the tibia etc.
Avascular Necrosis: It means necrosis if the bone due to inadequate blood supply. It complicates fracture when the blood supply of one fragment was derived from the other fragment when the bone was intact. So after fracture the blood supply of one fragment becomes completely deficient and undergoes avascular necrosis. This avascular necrosis will lead to non-union and osteoarthritis of the involved joint. Diagnosis is made by X-ray and the change takes about 1 to 3 months to develop. The avascular bone shows greater density due to the fact that it does not share in the general osteoporosis due to deficient blood supply.