The general method for osteomyelitis

In the developing world osteomyelitis almost never presents early enough for antibiotics to cure it, so drill all patients in whom you suspect it[md]unless they happen to be so privileged that you see them within 24 hours of the start of symptoms.

As soon as you have taken pus for culture, give antibiotics systemically in high doses. Sterilizing a patient's infected bone takes a long time, so continue to give them in adequate doses for 2 weeks in acute cases, or 3 to 6 weeks in chronic ones[md]if the organisms remain sensitive. Antibiotics are of limited value in chronic osteomyelitis, especially if there is a sequestrum, so don't waste them[md]they are no use after 6 weeks. Give them again as short-term cover when the patient has a sequestrectomy.

You have three ways to find the organism responsible[md]from a blood culture, from the pus, and from any septic lesion that might have been the source of his infection. If you cannot culture the organism, at least stain the pus to find out if Gram- positive cocci or Gram-negative bacilli are responsible.

In an area in which antibiotics have not been used, penicillin may be the drug of choice. Unfortunately, the staphylococci of most districts have become resistant to it, so that chloramphenicol is likely to be the most practical drug. Cloxacillin is an alternative, but is usually more expensive. Sensitivities differ from one district to another, so adjust your treatment accordingly. Even if you have no facilities for culture, other hospitals may have, so ask them what organisms they find, and what antibiotics they use.

IF YOU SUSPECT OSTEOMYELITIS[md]DRILL!

THE GENERAL METHOD [s8]FOR ACUTE OSTEOMYELITIS EXAMINATION. Look for a septic lesion anywhere, but especially on the child's skin, from which the infection may have spread. If you find one, culture it.

BLOOD CULTURES. If he is febrile, take a blood culture (if you can), and preferably 2 more at 2-hourly intervals, before you start antibiotic treatment. If treatment has already started, they will probably be negative.

X-RAYS should always be taken, because they will give you a baseline against which to assess future changes. Expect no bony changes for 10 days in an older child, or 5 days in an infant. Examine the edge of his bone with care[md]the earliest sign is the faintest second line of new bone about a millimetre away from the shaft. You will see this more easily if you look at the film obliquely.

TOURNIQUET. A bloodless field will make the operation much easier (3.9). Elevate his limb first. Don't use an exsanguinating bandage, because this may spread the infection.

CAUTION ! Avoid using a tourniquet on an SS or a CS sickler[md]his diagnosis should be obvious clinically. In practice, no harm follows from using one on an AS sickler. So, if your's is a high sickle-cell district, there is no need to test everyone for sickling before you apply one, even if it is practical, unless haemoglobin C is present in your community.

WHITE COUNT. This will show a polymorph leucocytosis and a shift to the left.

NEEDLE ASPIRATION may be useful in deciding where to drill. Unfortunately, if pus is present under the periosteum the patient has presented late. Good results are obtained by drilling bone earlier than this. Aspiration is also useful for diagnosing septic arthritis, but not for treatment. It is no substitute for drilling or for draining a joint!

CAUTION ! (1) Explore his bone, as in Section 7.5, whether or not you find pus. (2) Failure to aspirate pus does NOT exclude osteomyelitis! The indication for drilling is the suspicion of osteomyelitis!

SPLINTS. If necessary, splint his limb in the position of function, or use skin traction for a leg.

GENERAL CARE. If necessary, correct his dehydration. Ease his pain with analgesics.

ANTIBIOTICS. Start these immediately after you have taken a swab of pus from the drill hole, and if possible a blood culture also.

If you have been able to drain the lesion early and it is clinically quiescent, and there is no bone necrosis, 2 or 3 weeks' treatment will be enough.

Before you know the results of culture, or if culture is impossible, give him oral chloramphenicol 10 mg/kg 6-hourly, or 50 mg/kg/24 hours. If possible give it intravenously for the first 24 hours. Monitor his white count. Other possibilities are: (1) Intravenous benzyl penicillin, the adult dose being half a megaunit 6-hourly. Give children 25,000[nd]90,000 units/kg/24 hours. Divide the daily dose into 6 and give it 6 times a day. (2) Any antibiotic which is effective against the common staphylococci in your district. This might be cloxacillin or trimethoprim.

CAN AN OPERATION BE AVOIDED? Almost certainly not. If he has had symptoms for less than 24 hours, and, after 24 hours on antibiotics, he is showing obvious local and general signs of improvement, antibiotics alone may cure him. Drill all other cases. Although fever and local tenderness may be improving, the infection in his bone may still be continuing, so the lesion needs draining. If he is not obviously improving on antibiotics, don't delay operation more than 24 hours. You are unlikely to see these really early cases.