While bone resorption is commonly associated with many diseases or joint problems, the term "osteolysis" generally refers to a problem common to artificial joint replacements such as total hip replacements, total knee replacements and total shoulder replacements. Osteolysis can also be associated with the radiographic changes seen in those with bisphosphonate-related osteonecrosis of the jaw.

There are several biological mechanisms which may lead to osteolysis. In total hip replacement, the generally accepted explanation for osteolysis involves wear particles (worn off the contact surface of the artificial ball and socket joint). As the body attempts to clean up these wear particles (typically consisting of plastic or metal), it triggers an autoimmune reaction which causes resorption of living bone tissue. Osteolysis has been reported to occur as early as 12 months after implantation and is usually progressive. This may require a revision surgery (replacement of the prosthesis).

Although osteolysis itself is clinically asymptomatic, it can lead to implant loosening or bone breakage, which in turn causes serious medical problems.

Distal clavicular osteolysis (DCO) is often associated with problems weightlifters have with their acromioclavicular joints due to high stresses put on the clavicle as it meets with the acromion. This condition is often referred to as "weight lifter's shoulder". Medical ultrasonography readily depicts resorption of the distal clavicle as irregular cortical erosions, whereas the acromion remains intact. Associated findings may include distended joint capsule, soft-tissue swelling, and joint instability.

A common surgery to treat recalcitrant DCO is re-sectioning of the distal clavicle, removing a few millimetres of bone from the very end of the bone.

Paget's disease may be caused by a slow virus infection (i.e., paramyxoviridae) present for many years before symptoms appear. Associated viral infections include respiratory syncytial virus, canine distemper virus, and the measles virus. However, recent evidence has cast some doubt upon the measles association. Laboratory contamination may have played a role in past studies linking paramyxovirus (e.g. measles) to Paget's disease.

The disease is progressive and slowly worsens with time, although people may remain minimally symptomatic. Treatment is aimed at controlling symptoms, but there is no cure. Any bone or bones can be affected, but Paget's disease occurs most frequently in the spine, skull, pelvis, femur, and lower legs.

Osteogenic sarcoma, a form of bone cancer, is a rare complication of Paget's disease occurring in less than one percent of those affected. The development of osteosarcoma may be suggested by the sudden onset or worsening pain.

Acroosteolysis is resorption of the distal bony phalanges. Acroosteolysis has two patterns of resorption in adults: diffuse and bandlike.

The diffuse pattern of resorption has a widely diverse differential diagnosis which includes: pyknodysostosis, collagen vascular disease and vasculitis, Raynaud's neuropathy, trauma, epidermolysis bullosa, psoriasis, frostbite, sarcoidosis, hypertrophic osteoarthropathy, acromegaly, and advanced leprosy.

The bandlike pattern of resorption may be seen with polyvinyl chloride exposure and Hadju-Cheney syndrome.

A mnemonic commonly used for acro-osteolysis is PINCHFO.

Pyknodysostosis, Psoriasis,

Injury (thermal burn, frostbite),

Neuropathy (diabetes),

Collagen vascular disease (scleroderma, Raynaud's),

Hyperparathyroidism,

Familial (Hadju-Cheney, progeria),

Occupational (polyvinyl exposure),

Acroosteolysis may be associated with minimal skin changes or with ischemic skin lesions that may result in digital necrosis.

Arthritis mutilans' parent condition psoriatic arthritis leaves people with a mortality risk 60% higher than the general population, with premature death causes mirroring those of the general population, cardiovascular issues being most common. Life expectancy for people with psoriatic arthritis is estimated to be reduced by approximately 3 years.

To date, the specific cause of Gorham's disease remains unknown.

Bone mass and strength are obtained and maintained through a process of bone destruction and replacement that occurs at the cellular level throughout a person's life. Cells called osteoclasts secrete enzymes that dissolve old bone, allowing another type of cells called osteoblasts to form new bone. Except in growing bone, the rate of breakdown equals the rate of building, thereby maintaining bone mass. In Gorham's disease that process is disrupted.

Gorham and Stout found that vascular anomalies always occupied space that normally would be filled with new bone and speculated that the presence of angiomatosis may lead to chemical changes in the bone. Gorham and others speculated that such a change in the bone chemistry might cause an imbalance in the rate of osteoclast activity to osteoblast activity such that more bone is dissolved than is replaced. Beginning in the 1990s there were reports of elevated levels of a protein called interleukin-6 (IL-6) being detected in patients with the disease, leading some to suggest that increased levels of IL-6 and vascular endothelial growth factor (VEGF) may contribute to the chemical changes Gorham and others believed were the cause of this type of osteolysis.

In 1999 Möller and colleagues concluded, "The Gorham-Stout syndrome may be, essentially, a monocentric bone disease with a focally increased bone resorption due to an increased number of paracrine – or autocrine – stimulated hyperactive osteoclasts. The resorbed bone is replaced by a markedly vascularized fibrous tissue. The apparent contradiction concerning the presence or absence or the number of osteoclasts, may be explained by the different phases of the syndrome." They further stated that their histopathological study provided good evidence that osteolytic changes seen in Gorham's disease are the result of hyperactive osteoclastic bone. However, others have concluded that lymphangiomatosis and Gorham's disease should be considered as a spectrum of disease rather than separate diseases.

While there is consensus that Gorham's is caused by deranged osteoclastic activity, there is not yet conclusive evidence as to what causes this deranged behavior to begin.

Gorham's disease (pronounced GOR-amz), also known as Gorham vanishing bone disease and phantom bone disease, is a very rare skeletal condition of unknown cause, characterized by the uncontrolled proliferation of distended, thin-walled vascular or lymphatic channels within bone, which leads to resorption and replacement of bone with angiomas and/or fibrosis. Current treatments are experimental only.

Outcomes vary depending on the location of the disease, the degree of damage to the joint, and whether surgical repair was necessary. Average healing times vary from 55–97 days depending on location. Up to 1–2 years may be required for complete healing.

Arthritis mutilans occurs mainly in people who have pre-existing psoriatic arthritis, but can occur, if less often, in advanced rheumatoid arthritis; it can also occur independently. Psoriasis and psoriatic arthritis are interrelated heritable diseases, occurring with greater heritable frequency than rheumatoid arthritis, primary Sjogren's syndrome and thyroid disease. Psoriasis affects 2–3% of the Caucasian population, and psoriatic arthritis affects up to 30% of those. Arthritis mutilans presents in about 5–16% of psoriatic arthritis cases, involves osteolysis of the DIP and PIP joints, and can include bone edema, bone erosions, and new bone growth. Most often psoratic arthitis is seronegative for rheumatoid factor (occurring in only about 13% of cases), and has genetic risk factor overlap with ankylosing spondylitis with HLA-B27, IL-23R77, and IL-1, however, as of 2016, immunopathogenesis is unclear.

In reality, both of these mechanisms probably play a role in the development of a Charcot joint.

Metallosis is the putative medical condition involving deposition and build-up of metal debris in the soft tissues of the body.

Metallosis has been hypothesized to occur when metallic components in medical implants, specifically joint replacements, abrade against one another.

Metallosis has also been observed in some patients either sensitive to the implant or for unknown reasons even in the absence of malpositioned prosthesis. Though rare, metallosis has been observed at an estimated incidence of 5% of metal joint implant patients over the last 40 years. Women may be at slightly higher risk than men. If metallosis occurs, it may involve the hip and knee joints, the shoulder, wrist, or elbow joints.

The abrasion of metal components may cause metal ions to be solubilized. The hypothesis that the immune system identifies the metal ions as foreign bodies and inflames the area around the debris may be incorrect because of the small size of metal ions may prevent them from becoming haptens. Poisoning from metallosis is rare, but cobaltism is an established health concern. The involvement of the immune system in this putative condition has also been theorized but has never been proven.

Purported symptoms of metallosis generally include pain around the site of the implant, pseudotumors (a mass of inflamed cells that resembles a tumor but is actually collected fluids), and a noticeable rash that indicates necrosis. The damaged and inflamed tissue can also contribute to loosening the implant or medical device. Metallosis can cause dislocation of non-cemented implants as the healthy tissue that would normally hold the implant in place is weakened or destroyed. Metallosis has been demonstrated to cause osteolysis.

Women, those who are small in stature, and the obese are at greater risk for metallosis because their body structure causes more tension on the implant, quickening the abrasion of the metal components and the subsequent build-up of metallic debris.

In August 2010, DePuy recalled its hip replacement systems ASR XL Acetabular Hip Replacement System and ASR Hip Resurfacing System due to failure rates and side effects including metallosis. The recalls triggered a large number of lawsuits against DePuy and its parent company Johnson & Johnson upon claims that the companies knew about the dangers of the implants before they went on the market in the United States.

Several research groups are investigating cancer stem cells and their potential to cause tumors along with genes and proteins causative in different phenotypes.Radiotherapy for unrelated conditions may be a rare cause.

- Familial cases where the deletion of chromosome 13q14 inactivates the retinoblastoma gene is associated with a high risk of osteosarcoma development.

- Bone dysplasias, including Paget's disease of bone, fibrous dysplasia, enchondromatosis, and hereditary multiple exostoses, increase the risk of osteosarcoma.

- Li–Fraumeni syndrome (germline TP53 mutation) is a predisposing factor for osteosarcoma development.

- Rothmund–Thomson syndrome (i.e. autosomal recessive association of congenital bone defects, hair and skin dysplasias, hypogonadism, and cataracts) is associated with increased risk of this disease.

- Large doses of Sr-90 emission from nuclear reactor, nicknamed bone seeker increases the risk of bone cancer and leukemia in animals, and is presumed to do so in people.

Despite persistent rumors suggesting otherwise, there is no clear association between water fluoridation and cancer or deaths due to cancer, both for cancer in general and also specifically for bone cancer and osteosarcoma. Series of research concluded that concentration of fluoride in water doesn't associate with osteosarcoma. The beliefs regarding association of fluoride exposure and osteosarcoma stem from a study of US National Toxicology program in 1990, which showed uncertain evidence of association of fluoride and osteosarcoma in male rats. But there is still no solid evidence of cancer-causing tendency of fluoride in mice. Fluoridation of water has been practiced around the world to improve citizens' dental health. It is also deemed as major health success. Fluoride concentration levels in water supplies are regulated, such as United States Environmental Protection Agency regulates fluoride levels to not be greater than 4 milligrams per liter. Actually, water supplies already have natural occurring fluoride, but many communities chose to add more fluoride to the point that it can reduce tooth decay. Fluoride is also known for its ability to cause new bone formation. Yet, further research shows no osteosarcoma risks from fluoridated water in humans. Most of the research involved counting number of osteosarcoma patients cases in particular areas which has difference concentrations of fluoride in drinking water. The statistic analysis of the data shows no significant difference in occurrences of osteosarcoma cases in different fluoridated regions. Another important research involved collecting bone samples from osteosarcoma patients to measure fluoride concentration and compare them to bone samples of newly diagnosed malignant bone tumors. The result is that the median fluoride concentrations in bone samples of osteosarcoma patients and tumor controls are not significantly different. Not only fluoride concentration in bones, Fluoride exposures of osteosarcoma patients are also proven to be not significantly different from healthy people.

Whilst diet has long been known to be linked to laminitis, there is emerging evidence that breed and body condition also play a role. Levels of hormones, particularly adiponectin, and serum insulin are also implicated, opening up new possibilities for developing early prognostic tests and risk assessments.

The mechanism remains unclear and is the subject of much research. Three conditions are thought to cause secondary laminitis:

- Sepsis/endotoxemia or generalized inflammation

- Endocrinopathy

- Trauma: concussion or excessive weight-bearing

- Inflammation

Inflammatory events that are associated with laminitis include sepsis, endotoxemia, retained placenta, carbohydrate overload (excessive grain or pasture), enterocolitis, pleuropneumonia, and contact with black walnut shavings. In these cases, there is an increase in blood flow to the hoof, bringing in damaging substances and inflammatory cells into the hoof.

- Endocrinopathy

Endocrinopathy is usually the result of improper insulin regulation, and is most commonly seen with pituitary pars intermedia dysfunction (also called equine Cushing's syndrome) and equine metabolic syndrome (EMS), as well as obesity and glucocorticoid administration. In cases of EMS, most episodes occur in the spring when the grass is lush.

- Trauma

Mechanical laminitis starts when the hoof wall is pulled away from the bone or lost, as a result of external influences. Mechanical laminitis can occur when a horse habitually paws, is ridden or driven on hard surfaces ("road founder"), or in cases of excessive weight-bearing due to compensation for the opposing limb, a process called "support limb laminitis". Support limb laminitis is most common in horses suffering from severe injury to one limb, such as fracture, resulting in a non-weight bearing state that forces them to take excessive load on the opposing limb. This causes decreased blood flow to the cells, decreasing oxygen and nutrient delivery, and thus altering their metabolism which results in laminitis.

Most dental pain can be treated with routine dentistry. In rare cases, toothache can be a symptom representing a life-threatening condition, such as a deep neck infection (compression of the airway by a spreading odontogenic infection) or something more remote like a heart attack.

Dental caries, if left untreated, follows a predictable natural history as it nears the pulp of the tooth. First it causes reversible pulpitis, which transitions to irreversible pulpitis, then to necrosis, then to necrosis with periapical periodontitis and, finally, to necrosis with periapical abscess. Reversible pulpitis can be stopped by removal of the cavity and the placement of a sedative dressing of any part of the cavity that is near the pulp chamber. Irreversible pulpitis and pulp necrosis are treated with either root canal therapy or extraction. Infection of the periapical tissue will generally resolve with the treatment of the pulp, unless it has expanded to cellulitis or a radicular cyst. The success rate of restorative treatment and sedative dressings in reversible pulpitis, depends on the extent of the disease, as well as several technical factors, such as the sedative agent used and whether a rubber dam was used. The success rate of root canal treatment also depends on the degree of disease (root canal therapy for irreversible pulpitis has a generally higher success rate than necrosis with periapical abscess) and many other technical factors.

Osteosarcoma is the eighth-most common form of childhood cancer, comprising 2.4% of all malignancies in pediatric patients, and about 20% of all primary bone cancers.

Incidence rates for osteosarcoma in U.S. patients under 20 years of age are estimated at 5.0 per million per year in the general population, with a slight variation between individuals of black, Hispanic, and white ethnicities (6.8, 6.5, and 4.6 per million per year, respectively). It is slightly more common in males (5.4 per million per year) than in females (4.0 per million per year).

It originates more frequently in the metaphyseal region of tubular long bones, with 42% occurring in the femur, 19% in the tibia, and 10% in the humerus. About 8% of all cases occur in the skull and jaw, and another 8% in the pelvis.

Around 300 of the 900 people diagnosed in the United States will die each year. A second peak in incidence occurs in the elderly, usually associated with an underlying bone pathology such as Paget's disease of bone.

Wearing shoes to protect barefoot trauma has shown decrease in incidence in ainhum. Congenital pseudoainhum cannot be prevented and can lead to serious birth defects.

Toothache may occur at any age, in any gender and in any geographic region. Diagnosing and relieving toothache is considered one of the main responsibilities of dentists. Irreversible pulpitis is thought to be the most common reason that people seek emergency dental treatment. Since dental caries associated with pulpitis is the most common cause, toothache is more common in populations that are at higher risk of dental caries. The prevalence of caries in a population is dependent upon factors such as diet (refined sugars), socioeconomic status, and exposure to fluoride (such as areas without water fluoridation). In the United States, an estimated 12% of the general population reported that they suffered from toothache at some point in the six months before questioning. Individuals aged 18–34 reported much higher experience of toothache than those aged 75 or over. In a survey of Australian schoolchildren, 12% had experienced toothache before the age of five, and 32% by the age of 12. Dental trauma is extremely common and tends to occur more often in children than adults.

Giant-cell tumor of the bone accounts for 4-5% of primary bone tumors and about 20% of benign bone tumors. However, significantly higher incidence rates are observed in Asia, where it constitutes about 20% of all primary bone tumors in China. It is slightly more common in females, has a predilection for the epiphyseal/metaphyseal region of long bones, and generally occurs in the third to fourth decade. Although classified as a benign tumor, GCTOB has been observed to metastesize to the lungs in up to 5% of cases, and in rare instances (1-3%) can transform to the malignant sarcoma phenotype with equal disease outcome.

Shoulder problems including pain, are one of the more common reasons for physician visits for musculoskeletal symptoms. The shoulder is the most movable joint in the body. However, it is an unstable joint because of the range of motion allowed. This instability increases the likelihood of joint injury, often leading to a degenerative process in which tissues break down and no longer function well.

Shoulder pain may be localized or may be referred to areas around the shoulder or down the arm. Other regions within the body (such as gallbladder, liver, or heart disease, or disease of the cervical spine of the neck) also may generate pain that the brain may interpret as arising from the shoulder.

Winchester syndrome is a rare congenital connective tissue disease described in 1969, of which the main characteristics are short stature, marked contractures of joints, opacities in the cornea, coarse facial features, dissolution of the carpal and tarsal bones (in the hands and feet, respectively), and osteoporosis. Winchester syndrome was once considered to be related to a similar condition, multicentric osteolysis, nodulosis, and arthropathy (MONA). However, it was discovered that the two are caused by mutations found in different genes; they are now thought of as two separate disorders. Appearances resemble rheumatoid arthritis. Increased uronic acid is demonstrated in cultured fibroblasts from the skin and to a lesser degree in both parents. Despite initial tests not showing increased mucopolysaccharide excretion, the disease was regarded as a mucopolysaccharidosis. Winchester syndrome is thought to be inherited as an autosomal recessive trait.

Ainhum is an acquired and progressive condition, and thus differs from congenital annular constrictions. Ainhum has been much confused with similar constrictions caused by other diseases such as leprosy, diabetic gangrene, syringomyelia, scleroderma or Vohwinkel syndrome. In this case, it is called pseudo-ainhum, treatable with minor surgery or intralesional corticosteroids, as with ainhum. It has even been seen in psoriasis or it is acquired by the wrapping toes, penis or nipple with hairs, threads or fibers. Oral retinoids, such as tretinoin, and antifibrotic agents like tranilast have been tested for pseudo-ainhum. Impending amputation in Vohwinkel syndrome can sometimes be aborted by therapy with oral etretinate. It is rarely seen in the United States but often discussed in the international medical literature.

A number of tumors have giant cells, but are not true benign giant-cell tumors. These include, aneurysmal bone cyst, chondroblastoma, simple bone cyst, osteoid osteoma, osteoblastoma, osteosarcoma, giant-cell reparative granuloma, and brown tumor of hyperparathyroidism.