慢性骨髓炎.pptx

CHRONIC OSTEOMYELITIS陈孔冠Chronic osteomyelitis,one of the grand old diseases of orthopaedie surgery and a major cause of disability and crippling in the last century,is a complication of acure osteomyelitis in which the infection persists.Pathology Pus speads under the periosteum around cortex,which dies.The periosteum then forms a”new”bone around the abscess,leaving a mass of dead bone lying in a pocket of pus surrounded by living bone.The dead bone,which ie separate from theliving and cannot be discharged from the body beacause it is too large to pass down the sinus,is call a sequestrum.The living bone surrounding it is the involucrum.Clinical featuresWhthout treatment,the patient is left whth a large bony cavity containing pus and dead bone,communicating with the exter-ior through a sinus that discharges stinking pus and occasional pieces of deead bone,and requires regular dressing.Apart form the misery of such a condition,there are serious complications:1.Growth changes follow damage to the epiphyseal growth plates 2.The chronic infection leads to secondary amyloid disease.3.The skin margins can undergo malignant change.TreatmentToday,many of the chronic sinuses can be healed by eradication of dead bone and correct antibiotic treatment.This sounds straightforward but,in some patients,to remove all the dead bone means excising a complete fixation,and grafting the defect when the infection has been ersdicated.This is extensive surgery requiring prolonged admission to hospital and antibiotics must be given in adequate doses for long periods,sometimes for a year or more.SEPTIC ARTHRITISSeptic arthritis can arise in three ways:1.Spread from an infected bone2.Direct infection from a penetrating wound3.Bacteraemia Clinical featuresSeptic arthritis should be suspected in any hot swollen joint,particularly if there is infection elsewhere or the patient is systemically ill.Infected joints are extremely painful and the patient is systemically ill unless there is another debilitation condition such as diabetic.This is an important exception because diabetic patients are particularly susceptible to infection.Any unexplained joint effusion in a diabetic should be aspirated and sent for culture.Do not forget the gonococcus!The gonococcus has a special affinity for joints,hence its name,and should always be thought of when a young adult presents with septic arthritis.Untreated,septic arthritis destroys articular cartilage and lead to a bony ankylosis.If the patients is fortunate the joint becomes ankylosed in the position of function but more often the patient holds the joint in the position of ease,i.e.the position in which it is least painful becomes the joint cavity is greatest.The joint then becomes fused in a position that is not ideal for normal use.Occasionally the ankylosis occurs with fibrous tissue instead of bone and an arthrodesis is needed to probuce a better result.