Osteomyelitis is an inflammation of bone and bone marrow often resulting in bone destruction.

Osteomyelitis is caused by aerobic and anaerobic bacteria, mycobacteria and fungi. The organisms, Staphylococcus aureus, Staphylococcus epidermidis, and streptococci may be found in blood and tissue specimens. Contamination of bones may result from an open fracture, surgical procedures, gunshot wounds, diagnostic needle aspirations and therapeutic or self-administered drug injections. Infection of the bone occurs as a result of bacterial invasion from close contact with infection and skin breakdown in the setting of insufficient vessels. The most common sites in adults are the thoracic and lumbar vertebral bodies, and, for IV drug users, the most common site is the spine. Chronic osteomyelitis is caused by many forms of bacteria (polymicrobial). Risk factors include diabetes mellitus, and intravenous (IV) and indwelling catheters.

Signs and symptoms of acute osteomyelitis of the peripheral bones include: elevated temperature; weight loss; fatigue; localized warmth, swelling, and redness of the skin; and tenderness. Osteomyelitis that involves the vertebrae is characterized by localized back pain and muscle spasms that are unresponsive to conservative treatment. The person may be afebrile. Sensory and motor loss may occur if the infections progress to an epidural abscess. Signs shown on x-rays are described below under tests.

Radioisotope bone scans are abnormal earlier than x-rays; however, they are done to distinguish among infection, fractures and tumors. Magnetic resonance imaging (MRI) may be more sensitive in determining an infection than a bone scan. X-rays are done, which become abnormal by the second week showing bone destruction and abnormal cancellous bone, soft tissue swelling, periosteal elevation, periostitis, loss of vertebral body height or narrowing of the adjacent infected disk space, and destruction of the end plates above and below the disk. Complete blood counts (CBC) are done which may show an elevated white blood count (WBC), and an elevated erythrocyte sedimentation rate (ESR). C-reactive protein (CRP) count may better monitor the course of infection. CRP level drops rapidly with treatment, returning to normal within a week. Culture of blood or lesion tissue is needed for diagnosis. Bone biopsy may be done to provide tissue for culture and antibiotic sensitivity.

Initially, the primary treatment is antibiotic therapy until culture and sensitivity (C&S) tests are available. Antibiotics are given parenterally for 4 to 6 weeks. Current thought may be to switch to oral antibiotics after 2 to 3 weeks if certain criteria are met. These may include changes in physical examination, decrease C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), isolation of pathogens sensitive to oral antibiotics and adequate blood levels of the oral antibiotic. Surgical debridement of dead tissue in addition to antibiotics are required. Surgery may also be needed to drain abscesses or to stabilize the spine to prevent injury. The person may need skin grafts to close large surgical defects. Antibiotic treatment should continue for more than 3 weeks after debridement.

Progression of the disease to chronic osteomyelitis may occur and last from months to years with bone pain, tenderness, and sinus drainage. Chronic osteomyelitis is common in lower extremities, and in persons with impaired circulation such as those with diabetes mellitus. Recurrence of bone infection may result in anemia, markedly elevated erythrocyte sedimentation rate (ESR), weight loss, and weakness. Hyperplasia, squamous cell cancer or fibrosarcoma may occur in persistently infected tissue.

• The rating schedule for musculoskeletal was updated on February 7, 2021. Protection still does apply and should be considered with existing evaluations (38 CFR 3.951(a)).

• May be entitled to special monthly compensation where the veteran has a single service-connected disability rated as 100% with additional service-connected disability or disabilities independently ratable at 60% or more, which are separate and distinct from the 100% service-connected disability and involves different anatomical segments or bodily systems. See  38 CFR 3.350(i)(1) – Special Monthly Compensation (SMC).

• A rating of 10%, as an exception to the amputation rule, is to be assigned in any case of active osteomyelitis where the amputation rating for the affected part is no percent. This 10% rating and the other partial ratings of 30% or less are to be combined with ratings for ankylosis, limited motion, nonunion or malunion, shortening, etc., subject, of course, to the amputation rule. The 60% rating, as it is based on constitutional symptoms, is not subject to the amputation rule. A rating for osteomyelitis will not be applied following cure by removal or radical resection of the affected bone. 38 CFR 4.71 (a), [Schedule of ratings-musculoskeletal system]

• The 20% rating on the basis of activity within the past 5 years is not assignable following the initial infection of active osteomyelitis with no subsequent reactivation. The prerequisite for this historical rating is an established recurrent osteomyelitis. To qualify for the 10% rating, 2 or more episodes following the initial infection are required. This 20% rating or the 10% rating, when applicable, will be assigned once only to cover disability at all sites of previously active infection with a future ending date in the case of the 20% rating. 38 CFR 4.71 (a) [Schedule of ratings-musculoskeletal system]