Several risk factors of CMC OA of the thumb are known. Each of these risk factors does not cause CMC OA by itself, but acts as a predisposing factor influencing the process of OA in some way. Risk factors include: female gender, suffering from obesity, repetitive heavy manual labor, familial predisposition and hormonal changes, such as menopause.

CMC OA is the most common form of OA affecting the hand. Dahaghin et al. showed that about 15% of women and 7% of men between 50 and 60 years of age suffer from CMC OA of the thumb. However, in about 65% of people older than 55 years, radiologic evidence of OA was present without any symptoms. Armstrong et al. reported a prevalence of 33% in postmenopausal women, of which one third was symptomatic, compared to 11% in men older than 55 years. This shows CMC OA of the thumb is significantly more prevalent in women, especially in postmenopausal women, compared to men.

Supracondylar humerus fractures account for 55%-75% of all elbow fractures. They most commonly occur in children between ages 5–8, because remodeling of bone in this age group causes a decreased supracondylar anteroposterior diameter.

Gamekeeper's thumb and skier's thumb are two similar conditions, both of which involve insufficiency of the ulnar collateral ligament (UCL) of the thumb. The chief difference between these two conditions is that Skier's thumb is generally considered to be an acute condition acquired after a fall or similar abduction injury to the metacarpophalangeal (MCP) joint of the thumb, whereas gamekeeper's thumb typically refers to a chronic condition which has developed as a result of repeated episodes of lower-grade hyperabduction over a period of time. Gamekeeper's thumb is more difficult to treat because the UCL has lengthened and become thinner as a result of repeated injury. It is moderately painful compared to similar injuries.

In addition to skiing, this injury (resulting from forced abduction or hyperextension of the proximal phalanx of the thumb) is seen in a wide variety of other athletic endeavors. The most common mechanism of injury appears to be when a person extends the arm in an attempt to block a fall. The stress resulting from falling onto an abducted thumb produces a valgus force on the MCP joint of the thumb, resulting in a sprain or tear of the UCL.

In a recent study, 49% of UCL disruptions of the thumb were caused by a fall onto an outstretched hand. Sports injuries accounted for most of the remaining injuries, with only 2.4% acquired as a result of skiing injuries.

The etiology of the Galeazzi fracture is thought to be a fall that causes an axial load to be placed on a hyperpronated forearm. However, researchers have been unable to reproduce the mechanism of injury in a laboratory setting.

After the injury, the fracture is subject to deforming forces including those of the brachioradialis, pronator quadratus, and thumb extensors, as well as the weight of the hand. The deforming muscular and soft-tissue injuries that are associated with this fracture cannot be controlled with plaster immobilization.

A cubitus varus deformity is more cosmetic than limiting of any function, however internal rotation of the radius over the ulna may be limited due to the overgrowth of the humerus. This may be noticeable during an activity such as using a computer mouse.

A common cause is the supracondylar fracture of humerus. It can be corrected via a corrective osteotomy of the humerus and either internal or external fixation of the bone until union.

Distal radius fractures are the most common fractures seen in adults, with incidence in females outnumbering incidence in males by a factor of 2-3. Men who sustain distal radius fractures are usually younger, generally in their fifth decade (vs. seventh decade in females). The elderly are more susceptible because of the osteopenia and osteoporosis commonly seen in this age group. The majority of these fractures are extra-articular (i.e. not involving the joint).

This is also a common injury in children which may involve the growth plate (Salter-Harris fracture).

In young adults, the injury is often severe as a greater force is necessary to produce the injury.

According to the International Classification of Diseases, 9th Revision, Clinical Modification, ICD-9-CM, in 2008 the U.S. listed the diagonsis code for UCL injury as 841.1: Sprain ulnar collateral ligament. There were a total of 336 discharges of UCL injuries. Within the total discharges, separated by age groups: 18- to 44-year-olds; 165 people (49.17%). 45- to 64-year-olds; 91 (27.08%). 65- to 84-year-olds, 65 (19.35%) it shows that the ulnar collateral ligament injuries were more commonly found in men than women. There were 213 men compared to 123 women with ulnar collateral ligament injury. Most of these injuries were also paid through private insurance (170: 50.63%) and Medicare (70: 20.85%). The average estimated cost for the surgery also known as Tommy John surgery is $21,563.

The condition is called "Golfer's Elbow" because in making a golf swing this tendon is stressed, especially if a non-overlapping (baseball style) grip is used; many people, however, who develop the condition have never handled a golf club. It is also sometimes called "Pitcher's Elbow" due to the same tendon being stressed by the throwing of objects such as a baseball, but this usage is much less frequent. Other names are "Climber's Elbow" and "Little League Elbow": all of the flexors of the fingers and the pronators of the forearm insert at the medial epicondyle of the humerus to include: pronator teres, flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis, and palmaris longus; making this the most common elbow injury for rock climbers, whose sport is very grip intensive. The pain is normally caused due to stress on the tendon as a result of the large amount of grip exerted by the digits and torsion of the wrist which is caused by the use and action of the cluster of muscles on the condyle of the ulna.

Epicondylitis is much more common on the lateral side of the elbow (tennis elbow), rather than the medial side. In most cases, its onset is gradual and symptoms often persist for weeks before patients seek care. In golfer's elbow, pain at the medial epicondyle is aggravated by resisted wrist flexion and pronation, which is used to aid diagnosis. On the other hand, tennis elbow is indicated by the presence of lateral epicondylar pain precipitated by resisted wrist extension. Although the condition is poorly understood at a cellular and molecular level, there are hypotheses that point to apoptosis and autophagic cell death as causes of chronic lateral epicondylitis. The cell death may decrease the muscle density and cause a snowball effect in muscle weakness - this susceptibility can compromise a muscle's ability to maintain its integrity. So athletes, like pitchers, must work on preventing this cell death via flexibility training and other preventive measures.

Ulnar deviation, also known as ulnar drift, is a hand deformity in which the swelling of the metacarpophalangeal joints (the big knuckles at the base of the fingers) causes the fingers to become displaced, tending towards the little finger. Its name comes from the displacement toward the ulna (as opposed to radial deviation, in which fingers are displaced toward the radius). Ulnar deviation is likely to be a characteristic of rheumatoid arthritis, more than of osteoarthritis. Consideration should also be given to Pigmented Villonodular Synovitis, in the setting of ulnar deviation and metacarpophalangeal synovitis.

Ulnar deviation is also a physiological movement of the wrist, where the hand including the fingers move towards the ulna.

Ulnar deviation is a disorder in which flexion by ulnar nerve innervated muscles is intact while flexion on the median nerve side is not.

Gamekeeper's thumb (also known as skier's thumb or UCL tear) is a type of injury to the ulnar collateral ligament (UCL) of the thumb. The UCL may be torn, damaged or in some cases avulsed from its insertion site into the proximal phalanx of the thumb in the vast majority (approximately 90%) of cases. This condition is commonly observed among gamekeepers and Scottish fowl hunters, as well as athletes (such as volleyballers). It also occurs among people who sustain a fall onto an outstretched hand, frequently skiers.

People with diabetes mellitus are at higher risk for any kind of peripheral neuropathy, including ulnar nerve entrapments.

Cubital tunnel syndrome is more common in people who spend long periods of time with their elbows bent, such as when holding a telephone to the head. Flexing the elbow while the arm is pressed against a hard surface, such as leaning against the edge of a table, is a significant risk factor. The use of vibrating tools at work or other causes of repetitive activities increase the risk, including throwing a baseball.

Damage to or deformity of the elbow joint increases the risk of cubital tunnel syndrome. Additionally, people who have other nerve entrapments elsewhere in the arm and shoulder are at higher risk for ulnar nerve entrapment. There is some evidence that soft tissue compression of the nerve pathway in the shoulder by a bra strap over many years can cause symptoms of ulnar neuropathy, especially in very large-breasted women.

Colles fractures occur in all age groups, although certain patterns follow an age distribution.

- In the elderly, because of the weaker cortex, the fracture is more often extra-articular.

- Younger individuals tend to require a higher energy force to cause the fracture and tend to have more complex intra-articular fractures. In children with open epiphyses, an equivalent fracture is the "epiphyseal slip", as can be seen in other joints, such as a slipped capital femoral epiphysis in the hip. This is a Salter I or II fracture with the deforming forces directed through the weaker epiphyseal plate.

- More common in women because of post-menopausal osteoporosis.

Galeazzi fractures account for 3-7% of all forearm fractures. They are seen most often in males. Although Galeazzi fracture patterns are reportedly uncommon, they are estimated to account for 7% of all forearm fractures in adults. They are associated with a fall on an outstretched arm.

Radial dysplasia, also known as radial club hand or radial longitudinal deficiency, is a congenital difference occurring in a longitudinal direction resulting in radial deviation of the wrist and shortening of the forearm. It can occur in different ways, from a minor anomaly to complete absence of the radius, radial side of the carpal bones and thumb. Hypoplasia of the distal humerus may be present as well and can lead to stiffnes of the elbow. Radial deviation of the wrist is caused by lack of support to the carpus, radial deviation may be reinforced if forearm muscles are functioning poorly or have abnormal insertions. Although radial longitudinal deficiency is often bilateral, the extent of involvement is most often asymmetric.

The incidence is between 1:30,000 and 1:100,000 and it is more often a sporadic mutation rather than an inherited condition. In case of an inherited condition, several syndromes are known for an association with radial dysplasia, such as the cardiovascular Holt-Oram syndrome, the gastrointestinal VATER syndrome and the hematologic Fanconi anemia and TAR syndrome. Other possible causes are an injury to the apical ectodermal ridge during upper limb development, intrauterine compression, or maternal drug use (thalidomide).

In children the outcome of distal radius fracture treatment in casts is usually very successful with healing and return to normal function expected. Some residual deformity is common but this often remodels as the child grows. In the elderly, distal radius fractures heal and may result in adequate function following non-operative treatment. A large proportion of these fractures occur in elderly people that may have less requirement for strenuous use of their wrists. Some of these patients tolerate severe deformities and minor loss of wrist motion very well even without reduction of the fracture. In this low demand group only a short period of immobilization is indicated as rapid mobilization improves functional outcome.

In younger patients the injury requires greater force and results in more displacement particularly to the articular surface. Unless an accurate reduction of the joint surface is obtained, these patients are very likely to have long term symptoms of pain, arthritis, and stiffness.

Workers in certain fields are at risk of repetitive strains. Most occupational injuries are musculoskeletal disorders, and many of these are caused by cumulative trauma rather than a single event. Miners and poultry workers, for example, must make repeated motions which can cause tendon, muscular, and skeletal injuries.

Leri-Weill dyschondrosteosis is a pseudoautosomal dominant disorder which occurs more frequently in females and is due to a mutation, deletion or duplication of the SHOX gene. The SHOX gene plays a particularly important role in the growth and maturation of bones in the arms and legs. The SHOX gene is located within band Xp22.3 of the pseudoautosomal region of the X chromosome, which escapes X-inactivation. Homozygous SHOX gene mutations result in Langer mesomelic dysplasia.

It is a congenital subluxation or dislocation of the ulna's distal end, due to malformation of the bones. Sometimes, minor abnormalities of other bone structures, often caused by disease or injury, such as a fracture of the distal end of the radius with upward displacement of the distal fragment. The deformity varies in degree from a slight protrusion of the lower end of the ulna, to complete dislocation of the inferior radio-ulnar joint with marked radial deviation of the hand. Severe deformities are associated with congenital absence or hypoplasia of the radius.

The male:female rate of this disorder is 1:4. The incidence is unknown, and there is no described racial predominance. Even though Madelung's Deformity is considered a congenital disorder, symptoms sometimes aren't seen until adulthood. In most cases, symptoms find their onset during midchildhood. At this age, the relatively slower growth of the ulnar and palmar part of the radius, leads to an increasingly progressive deformity. Pain and deformity are the main symptoms patients present with. Typical clinical presentation consists of a short forearm, anterior-ulnar bow of the radius and a forward subluxation of the hand on the forearm. As mentioned before, the severity of the disorder varies greatly, which also leads to a spectrum of presentation.

Golfer's elbow, or medial epicondylitis, is tendinosis of the medial epicondyle on the inside of the elbow. It is in some ways similar to tennis elbow, which affects the outside at the lateral epicondyle.

The anterior forearm contains several muscles that are involved with flexing the digits of the hand, and flexing and pronating the wrist. The tendons of these muscles come together in a common tendinous sheath, which originates from the medial epicondyle of the humerus at the elbow joint. In response to minor injury, or sometimes for no obvious reason at all, this point of insertion becomes inflamed.

The radial head fracture is usually managed by open reduction internal fixation; if the fracture is too comminuted, a radial head implant can be used. Excision of the radial head should be avoided, as the radius will migrate proximally leading to wrist pain and loss of pronation and supination of the wrist. Delayed treatment of the radial head fracture will also lead to proximal migration of the radius.

The distal radio-ulnar joint dislocation can be reduced by supination of the forearm, and may be pinned in place for 6 weeks to allow healing of the interosseous membrane.

A Stener lesion is a type of traumatic injury to the thumb. It occurs when the aponeurosis of the adductor pollicis muscle becomes interposed between the ruptured ulnar collateral ligament (UCL) of the thumb and its site of insertion at the base of the proximal phalanx. No longer in contact with its insertion site, the UCL cannot spontaneously heal.

Monteggia fractures may be managed conservatively in children with closed reduction (resetting and casting), but due to high risk of displacement causing malunion, open reduction internal fixation is typically performed.

Osteosynthesis (open reduction and internal fixation) of the ulnar shaft is considered the standard of care in adults. It promotes stability of the radial head dislocation and allows very early mobilisation to prevent stiffness. The elbow joint is particularly susceptible to loss of motion.

The Pink and Pulseless hand in supracondylar fracture has been assigned the following causes:

1. tear or entrapment of the brachial artery

2. spasm of the artery and

3. compression of the artery relieved by manipulation of the fracture

4. compression of median nerve.

Thus there is loss of circulation of forearm, causing lack of reperfusion of tissues resulting in tissue death causing compartment syndrome.

Therefore, the complications of elbow dislocations include the following:

- Posttraumatic periarticular calcification, which occurs in 3-5% of elbow injuries

- Myositis ossificans or calcific tendinitis

- Neurovascular injuries (8-21% of cases) — palsy to the anterior interosseus nerve at time of index injury is most common, followed by brachial artery injuries (5-13%). Injury to the ulnar nerve is reported with percutaneous pinning through the medial epicondyle.

- Osteochondral defects, intra-articular loose bodies, and avascular necrosis of the capitulum

- Instability