Osteomyelitis Etiology Pathogenesis Differential Diagnosis And Treatment Biology Essay

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

Osteomyelitis presents as an infection of the bone that is caused by different forms of bacteria. The infection of the cortical and medullary bone can often lead to distinct forms of necrosis, formation of new bone, and obliteration of the bone in its entirety. (3) It is a disease that can cause morbidity. Cases are usually based on a causative agent, the infections duration, the anatomy of the infected bone, and the path the organisms follow in order to gain passage into the bone. (4)With the increasing cases of osteomyelitis being linked to diabetes, peripheral vascular disease, and the aging population, this disease is becoming more difficult to treat and cure. (1,2,3,4,5,6)

Over the past few decades, osteomyelitis has changed its form. Evolving into a disease with many backgrounds, this disease takes heed amongst many polymicrobials. In the past, osteomyelitis cases involved a link to strains of Staphylococcus Aureus. Although Staphylococcus Aureus, also known as S. Aureus, a bacterium, is still the most common organism involved in this disease, a number of infections have been caused by gram negative organisms. These cases would find treatment in surgical debridement and therapy for 4 to 6 weeks of methicillin.(1) Some organisms include mycobacterium, Pseudomonas Aeruginosa, which is found in drug addicts, and organisms that are active in the Gastrointestinal Tract of the elderly. Coagulase-negative staphylococci are pathogens whom also play a distinct role in the presentation of osteomyelitis. (1,4)


      Osteomyelitis is caused by microorganisms entering the bone by various mechanisms. These mechanisms include inoculation by distant substances, direct transmission from neighboring soft tissue infection, and hematogenous dissemination via bacteriemia. (3) Ischemia, trauma, and foreign substances can expose vulnerable sites to which bacteria penetrates defenses set by the host. Enzymes are released by a number of phagocytes that attempt to hold the infection. Bacteria can connect tightly to damaged bone. Through interaction with the damaged bone, bacteria withdraws from the host defenses and enters inside the osteoblasts. Furthermore, the infection can lead to sensitive neutrophils, congested blood vessels, and microorganisms which is the basis for acute osteomyelitis.(2) Acute osteomyelitis is an infection that may develop over a short span of time. In children, this osteomyelitis may present as fever, chills, and even pain. The feature that is known to distinguish chronic osteomyelitis is the depletion of living osteocytes also known as necrotic bone.(3) This can occur when osteomyelitis is not properly treated, thus the chronic type of infection may occur.(1) Moreover, two classification systems exist in the Waldvogel and Cierny-Mader Classification in regards to osteomyelitis.  Waldvogel classifies adult osteomyelitis by chronicity and its pathogenesis. These categories of osteomyelitis are labeled hematogenous osteomyelitis, osteomyelitis secondary to a contiguous focus of infection, and chronic osteomyelitis. Acute Hematogenous Osteomyelitis involves a single bone, usually the tibia or femur, and is where bacteria resides in the metaphysis of growing bones. Hematogenous infection in adults is uncommon for the long bones and thus involves the diaphysis. It accounts for 20% of cases of osteomyelitis and is the main cause for children.(3) The common site that affects the adults the most is the vertebrae where hematogenous ostemyelitis thrives. Patients with this infection tend to have pain in the neck and back. Osteomyelitis secondary to a contiguous focus of infection occurs mostly in adults and accounts for about 80% of all cases.(3) This can occur through bites, wounds and open fractures. The main group of focus here are the individuals who have Peripheral Arterial Disease and Diabetes. This can result in numerous amputations for diabetics. The patient here does not have the proper knowledge to know that the infection is flourishing inside the bone. Trauma and sores can make the foot vulnerable to diabetic neuropathy. In regards to chronic osteomyelitis, about 5% of cases from acute hematogenous osteomyelitis leads to chronic osteomyelitis.(3) Chronic infection tends to have a more contiguous-focus origin than that of a hematogenous osteomyelitis due to the presence of foreign substances inhabiting the infection for a significant amount of time. Furthermore, Cierny- Mader classifies by condition of the patient by an anatomic stage and a physiological stage. (3,5)

Differential Diagnosis

      Diagnosis of osteomyelitis may involve numerous procedures. These procedures should be a factor in patients with fever, inflammatory reactions, regional skeletal pain, and positive blood cultures. Blood tests are usually done in order to determine the amount of white blood cells present to battle with the infection. Blood is cultured to reveal the causative bacteria in the specimen. Moreover, an Erythrocyte Sedimentation Rate (ESR), blood cell count, and C-reactive protein test can help to indicate osteomyelitis. (2,3)

      Scanning examinations such as Magnetic Resonance Imaging(MRI), x-rays, three phase bone scans , and other radionuclide studies, may help determine bone inflammation. Bone inflammation is witnessed through injection of radioactive elements into the blood stream. Biopsies can also be performed in order to determine various bacteria lurking in the area. (1,2)The differential diagnosis for osteomyelitis is neuroarthropathy of the foot. On radiographs, bone infections are equivalent to bone lesions. However, if there is no ulcer present, the diagnosis can be viewed as damage to the bone and thus, is a result of neuroarthropathy. (2,3)


      The two forms of treatment of osteomyelitis most commonly used are surgical therapy and antibiotic therapy. Surgical therapy is distinguished based on the infections extent. When dealing with acute osteomyelitis, the key component deals with debridement of the dead tissue. In regards to chronic osteomyelitis, there is a resection of foreign substances, and also debridement of soft tissue.(1,2,3,4) Skin and bone grafts may be used to potentiate the start of new bone growth by covering the wound. Furthermore, surgical approach may increase the chances for re-ulceration. This surgical approach is understood with help from biomechanics of foot function. (2)

      Antibiotic therapy is used to kill bacteria. There is oral and intravenous therapy used to target these causative organisms. Intravenous antimicrobial therapy is the treatment of choice for chronic osteomyelitis. In adults, four to six weeks of intravenous antibiotic treatment is needed along with sufficient bed rest. Usually, surgery may be needed to drain the pus accumulated and to clean the affected areas. (4)

      Alternative treatments also exist in attempts to treat osteomyelitis. Some have recommended that increasing the use of particular vitamin supplements, garlic extracts, herbal remedies such as Echinacea, golden seal, and even ginseng may help to relieve certain pains associated with infections. Homeopathic remedies may be useful in counter acting inflammation. (7) Antibiotic-impregnated acrylic beads have also been used for bone infection treatment. The beads should be used along with certain antibiotics. This requires adequate surgical placement in the area specified. Non-biodegradeable beads may be removed surgically after 2-4 weeks. While biodegradeable beads do not require surgical removal and may help for an extended period of time. (3,7)


      Osteomyelitis requires excellent care of injuries and wounds. It may require surgical treatment and antibiotic therapy in order to reduce its effects. Osteomyelitis accounts for a great percentage of cases in adults. Typically, diagnosis of osteomyelitis presents with pain, fever, and other inflammatory signs due to bony infection. This disease has surfaced in Peripheral Arterial Disease and in the small bones of diabetics. Once a bone infection is confirmed by efficient procedures such as biopsy, treatment should follow accordingly. Following protocol consisting of debridement and appropriate IV antibiotics for 4 to 6 weeks helps in the general outreach of proper osteomyelitis management. (1,2,3,4,5,6)