Anatomy

Osteomyelitis is an infection of bone or bone marrow, usually caused by pyogenic bacteria or mycobacteria . It can be usefully subclassified on the basis of the causative organism, the route, duration and anatomic location of the infection. Treatment Osteomyelitis often requires prolonged antibiotic therapy, with a course lasting a matter of weeks or months. A PICC line or central venous catheter is often placed for this purpose. Osteomyelitis also may require surgical debridement. Severe cases may lead to the loss of a limb. Initial first line antibiotic choice is determined by the patient's history and regional differences in common infective organisms. American artist Thomas Eakins in 1875 depicted a surgical procedure for osteomyelitis in a famous oil painting titled "The Gross Clinic", now part of Jefferson Medical College. Prior to the widespread availability and use of antibiotics, blow fly larvae were sometimes deliberately introduced to the wounds to feed on the infected material, effectively scouring clean. Hyperbaric oxygen therapy has been shown to be a useful adjunct to the treatment of refractory osteomyelitis. A treatment lasting 42 days is practiced in a number of facilities

Causes Staphylococcus aureus is the organism most commonly isolated from all forms of osteomyelitis. Hematogenously seeded osteomyelitis is seen most frequently in children, and nearly 90% of cases are caused by Staphylococcus aureus. In infants, S. aureus, Group B streptococci (most common) and Escherichia coli are commonly isolated; in children from 1 to 16 years of age, S. aureus, Streptococcus pyogenes, and Haemophilus influenzae are common. In some subpopulations, including intravenous drug users and splenectomized patients, Gram negative bacteria, including enteric bacilli, are significant pathogens.

Osteoarthritis (OA, also known as degenerative arthritis, degenerative joint disease), is a clinical syndrome in which low-grade inflammation results in pain in the joints, caused by abnormal wearing of the cartilage that covers and acts as a cushion inside joints and destruction or decrease of synovial fluid that lubricates those joints. As the bone surfaces become less well protected by cartilage, the patient experiences pain upon weight bearing, including walking and standing. Due to decreased movement because of the pain, regional muscles may atrophy, and ligaments may become more lax. OA is the most common form of arthritis and the leading cause of chronic disability in the United States. Types: Primary This type of OA is a chronic degenerative disorder related to but not caused by aging, as there are people well into their nineties who have no clinical or functional signs of the disease. As a person ages, the water content of the cartilage decreases due to a reduced proteoglycan content, thus causing the cartilage to be less resilient. Without the protective effects of the proteoglycans, the collagen fibers of the cartilage can become susceptible to degradation and thus exacerbate the degeneration. Inflammation of the surrounding joint capsule can also occur, though often mild (compared to that which occurs in rheumatoid arthritis). This can happen as breakdown products from the cartilage are released into the synovial space, and the cells lining the joint attempt to remove them. New bone outgrowths, called "spurs" or osteophytes, can form on the margins of the joints, possibly in an attempt to improve the congruence of the articular cartilage surfaces. These bone changes, together with the inflammation, can be both painful and debilitating. Secondary: This type of OA is caused by other factors or diseases but the resulting pathology is the same as for primary OA: Signs and symptoms The main symptom is acute pain, causing loss of ability and often stiffness. "Pain" is generally described as a sharp ache, or a burning sensation in the associated muscles and tendons. OA can cause a crackling noise (called "crepitus") when the affected joint is moved or touched, and patients may experience muscle spasm and contractions in the tendons. Occasionally, the joints may also be filled with fluid. Humid weather increases the pain in many patients.

Causes Although it commonly arises from trauma, osteoarthritis often affects multiple members of the same family, suggesting that there is hereditary susceptibility to this condition. A number of studies have shown that there is a greater prevalence of the disease between siblings and especially identical twins, indicating a hereditary basis[citation needed]. Up to 60% of OA cases are thought to result from genetic factors. Researchers are also investigating the possibility of allergies, infections, or fungi as a cause. There is some evidence that allergies, whether fungal, infectious or systemically induced, may be a significant contributing factor to the appearance of osteoarthritis in a synovial sac.

Diagnosis Diagnosis is normally done through x-rays. This is possible because loss of cartilage, subchondral ("below cartilage") sclerosis, subchondral cysts, narrowing of the joint space between the articulating bones, and bone spur formation (osteophytes) show up clearly on x-rays. Plain films, however, often do not correlate well with the findings of physical examination of the affected joints. Treatment Generally speaking, the process of clinically detectable osteoarthritis is irreversible, and typical treatment consists of medication or other interventions that can reduce the pain of OA and thereby improve the function of the joint.

Gout (also called metabolic arthritis) is a disease created by a buildup of uric acid. In this condition, monosodium urate or uric acid crystals are deposited on the articular cartilage of joints, tendons and surrounding tissues due to elevated concentrations of uric acid in the bloodstream. This provokes an inflammatory reaction of these tissues. Signs and symptoms Gout is characterized by excruciating, sudden, unexpected, burning pain, as well as swelling, redness, warmth, and stiffness in the affected joint. This occurs commonly in men in their toes but can appear in other parts of the body and affects women as well. Low-grade fever may also be present. The patient usually suffers from two sources of pain. The crystals inside the joint cause intense pain whenever the affected area is

moved. The inflammation of the tissues around the joint also causes the skin to be swollen, tender and sore if it is even slightly touched. For example, a blanket or even the lightest sheet draping over the affected area could cause extreme pain. Diagnosis Clinically, gout can be hard to distinguish from several other conditions, including chondrocalcinosis. Chondrocalcinosis is a very similar disease, caused by deposition of calcium pyrophosphate rather than uric acid. Treatment Acute attacks The first line of treatment should be pain relief. Once the diagnosis has been confirmed, the drugs of choice are indomethacin, other nonsteroidal anti-inflammatory drugs (NSAIDs), oral glucocorticoids,[15] or intraarticular glucocorticoids administered via a joint injection. Colchicine was previously the drug of choice in acute attacks of gout, as it impairs the motility of granulocytes and can prevent the inflammatory phenomena that initiate an attack. Colchicine should be taken within the first 12 hours of the attack and usually relieves the pain within 48 hours, although side effects (gastrointestinal upset such as diarrhea and nausea) can complicate its use. NSAIDs are the preferred form of analgesia for patients with gout.

Infectious arthritis is a form of joint inflammation caused by a germ. The germ can be a bacterium, a virus or a fungus. Infection of the joints usually occurs after a previous infection elsewhere in the body. There is usually only one joint involved, though sometimes two or three joints can become infected. Mostly, infectious arthritis affects the large joints (shoulders, hips, knees), but smaller joints (fingers, ankles) can also be involved. The symptoms infectious arthritis vary according to the type of germ causing it. If the arthritis is caused by a bacterium, inflammation is generally located in only one place or area. The infection is often accompanied by fever and chills and its onset is quite sudden. With infectious arthritis caused by a virus, there is usually no fever, but there is an aching feeling all over the body. Inflammation caused by a fungal infection can be in one area or

throughout the body, and it usually occurs very slowly, over weeks or months. You may have a mild fever or no fever at all. Medication Anti-inflammatory medication is often given to treat the pain and swelling of infectious arthritis. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a type of medication that helps reduce the pain and swelling of the joints and decrease stiffness. However, they do not prevent further joint damage. Surgery If your infectious arthritis is caused by a fungus, you and your doctor may consider surgery to remove the infection from the joint.

Osteoporosis is a disease of bone that leads to an increased risk of fracture. In osteoporosis the bone mineral density (BMD) is reduced, bone microarchitecture is disrupted, and the amount and variety of noncollagenous proteins in bone is altered. Osteoporosis is defined by the World Health Organization (WHO) in women as a bone mineral density 2.5 standard deviations below peak bone mass (20-year-old healthy female average) as measured by DXA; the term "established osteoporosis" includes the presence of a fragility fracture.[1] Osteoporosis is most common in women after menopause, when it is called postmenopausal osteoporosis, but may also develop in men, and may occur in anyone in the presence of particular hormonal disorders and other chronic diseases or as a result of medications, specifically glucocorticoids, when the disease is called steroid- or glucocorticoid-induced osteoporosis (SIOP or GIOP). Given its influence on the risk of fragility fracture, osteoporosis may significantly affect life expectancy and quality of life. Signs and symptoms Osteoporosis itself has no specific symptoms; its main consequence is the increased risk of bone fractures. Osteoporotic fractures are those that occur in situations where healthy people would not normally break a bone; they are therefore regarded as fragility fractures. Typical fragility fractures occur in the vertebral column, rib, hip and wrist. Diseases and disorders Many diseases and disorders have been associated with osteoporosis. For some, the underlying mechanism influencing the bone metabolism is straight-forward, whereas for others the causes are multiple or unknown.

- In general, immobilization causes bone loss (following the 'use it or lose it' rule). For example, localized osteoporosis can occur after prolonged immobilization of a fractured limb in a cast. This is also more common in active patients with a high bone turn-over (for example, athletes). Other examples include bone loss during space flight or in people who are bedridden or wheelchair-bound for various reasons. - Hypogonadal states can cause secondary osteoporosis. These include Turner syndrome, Klinefelter syndrome, Kallmann syndrome, anorexia nervosa, andropause, hypothalamic amenorrhea or hyperprolactinemia. In females, the effect of hypogonadism is mediated by estrogen deficiency. It can appear as early menopause (<45 years) or from prolonged premenopausal amenorrhea (>1 year). A bilateral oophorectomy (surgical removal of the ovaries) or a premature ovarian failure cause deficient estrogen production. In males, testosterone deficiency is the cause (for example, andropause or after surgical removal of the testes). - Endocrine disorders that can induce bone loss include Cushing's syndrome, hyperparathyroidism, thyrotoxicosis, hypothyroidism, diabetes mellitus type 1 and 2, acromegaly and adrenal insufficiency. In pregnancy and lactation, there can be a reversible bone loss. - Malnutrition, parenteral nutrition and malabsorption can lead to osteoporosis. Nutritional and gastrointestinal disorders that can predispose to osteoporosis include coeliac disease, Crohn's disease, lactose intolerance, surgery (after gastrectomy, intestinal bypass surgery or bowel resection) and severe liver disease (especially primary biliary cirrhosis). Patients with bulemia can also develop osteoporosis. Those with an otherwise adequate calcium intake can develop osteoporosis due to the inability to absorb calcium and/or vitamin D. Other micro-nutrients such as vitamin K or vitamin B12 deficiency may also contribute. - Patients with rheumatologic disorders like rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus and polyarticular juvenile idiopathic arthritis are at increased risk of osteoporosis, either as part of their disease or because of other risk factors (notably corticosteroid therapy). Systemic diseases such as amyloidosis and sarcoidosis can also lead to osteoporosis. - Renal insufficiency can lead to osteodystrophy. - Hematologic disorders linked to osteoporosis are multiple myeloma and other monoclonal gammopathies, lymphoma and leukemia, mastocytosis, hemophilia, sickle-cell disease and thalassemia. - Several inherited disorders have been linked to osteoporosis. These include osteogenesis imperfecta, Marfan syndrome, hemochromatosis,

hypophosphatasia, glycogen storage diseases, homocystinuria, EhlersDanlos syndrome, porphyria, Menkes' syndrome, epidermolysis bullosa and Gaucher's disease. - People with scoliosis of unknown cause also have a higher risk of osteoporosis. Bone loss can be a feature of complex regional pain syndrome. It is also more frequent in people with Parkinson's disease and chronic obstructive pulmonary disease. Medication Bisphosphonates are the main pharmacological measures for treatment. However, newer drugs have appeared in the 1990s, such as teriparatide and strontium ranelate. Bisphosphonates In confirmed osteoporosis, bisphosphonate drugs are the first-line treatment in women. The most often prescribed bisphosphonates are presently sodium alendronate (Fosamax) 10 mg a day or 70 mg once a week, risedronate (Actonel) 5 mg a day or 35 mg once a week and or ibandronate (Boniva) once a month. Oral bisphosphonates are relatively poorly absorbed, and must therefore be taken on an empty stomach, with no food or drink to follow for the next 30 minutes. They are associated with esophagitis and are therefore sometimes poorly tolerated; weekly or monthly administration (depending on the preparation) decreases likelihood of esophagitis, and is now standard. Although intermittent dosing with the intravenous formulations such as zolendronate avoids oral tolerance problems, these agents are implicated at higher rates in a rare but unpleasant mouth disease called osteonecrosis of the jaw. For this reason, oral bisphosphonate therapy is probably to be preferred, and prescribing advice now recommends any remedial dental work to be carried out prior to commencing treatment. Teriparatide Recently, teriparatide (Forteo, recombinant parathyroid hormone residues 1–34) has been shown to be effective in osteoporosis. It acts like parathyroid hormone and stimulates osteoblasts, thus increasing their activity. It is used mostly for patients with established osteoporosis (who have already fractured), have particularly low BMD or several risk factors for fracture or cannot tolerate the oral bisphosphonates. It is given as a daily injection with the use of a pen-type injection device. Teriparatide is only licensed for treatment if

bisphosphonates have failed or are contraindicated (however, this differs by country and is not required by the FDA in the USA. However, patients with previous radiation therapy, or Paget's disease, or young patients should avoid this medication). Strontium ranelate Oral strontium ranelate is an alternative oral treatment, belonging to a class of drugs called "dual action bone agents" (DABAs) by its manufacturer. It has proven efficacy, especially in the prevention of vertebral fracture. In laboratory experiments, strontium ranelate was noted to stimulate the proliferation of osteoblasts, as well as inhibiting the proliferation of osteoclasts. Strontium, no matter what the form, must be water-soluble and ionized in the stomach acid. Stontium is then protein-bound for transport from the intestinal tract into the blood stream. Unlike drugs like sodium alendronate (Fosamax), strontium doesn't inhibit bone recycling and, in fact, may produce stronger bones. Studies have shown that after five years alendronate may even cause bone loss, while strontium continues to build bone during lifetime use.[citation needed] Strontium must not be taken with food or calcium-containing preparations as calcium competes with strontium during uptake. However, it's essential that calcium, magnesium, and vitamin D in theraputic amounts must be taken daily, but not at the same time as strontium. Strontium should be taken on an empty stomach at night

Pathophysiology of skeletal System Anatomy & Physiology

Osteoporosis Osteomyelitis Osteoarthitis Infectious Arthritis

Gout