Elbow injuries
From Medical-Wiki
Elbow injuries may be acute or caused by chronic overuse. As the American public has embraced athletics, the latter has become an increasingly common problem. A sport or occupation that requires repetitive flexion-extension or wrist motion has the capacity damage the muscles (and their tendons) that produce these actions. This is the case with lateral epicondylitis and medial epicondylitis.
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Soft tissue injuries of the elbow
Tennis elbow - Lateral epicondylitis
The extensor carpi radialis brevis (ECRB), extensor digitorum communis, extensor carpi radialis longus, and extensor carpi ulnaris attach in an area over the lateral epicondyle of the humerus and just below the epicondyle. These are the wrist extensor and supinator muscles. Any activity that requires a wrist to snap or severely supinate stresses the attachment of these muscles. Sometimes this is because an athlete is being too active. Sometimes it is due to improper technique. Carpenters, jackhammer operators, people using hand-held power tools, production line workers, those playing string instruments, drummers, and those who work at computers or keyboards in a setting of poor ergonomics are all prone to lateral epicondylitis. [1]
Physical examination reveals tenderness and sometimes obvious swelling at the attachment of the muscles. In more severe cases, even shaking hands will produce pain.
One of the problems with this condition is the lack of high-quality clinical trials evaluating the many treatment modalities that are used. Watchful waiting, ultrasonography, iontophoresis with nonsteroidal anti-inflammatory drugs. topical nonsteroidal anti-inflammatory drugs, inelastic, nonarticular, proximal forearm straps, i.e. tennis elbow braces, and progressive resistance exercises all appear to have some effect in improving the condition. Basically, all treatment is an effort to reduce the stress on the point of tendinous attachment—even the activities of daily life. This is why the ongoing use of a forearm strap is exceedingly helpful. It basically functions to alter the fulcrum point of the muscles away from the epicondyle towards the body of the muscle. [2]
The modality that appears to offer the most dramatic improvement is local injection of corticosteroids. However, even this has not been subject to rigorous studies. [3]
Golfer's elbow - Medial epicondylitis
Medial epicondylitis (ME) is also called golfer’s elbow. This injury is caused by overuse of the flexor-pronator muscles. It is not as common as lateral epicondylitis. Physical load factors, smoking, obesity, repetitive movements, and forceful activities are associated with an increased incidence of medial epicondylitis. [4]
The pronator teres, flexor carpi radialis, and palmaris longus are the muscles primarily responsible for pronation and flexion. These muscles attach on the anterior medial epicondyle. The flexor carpi ulnaris and flexor digitorum may also be involved, but their involvement is less common.
Patients with ME will typically present with pain over the medial epicondyle made worse with wrist flexion and forearm pronation. Like LE, patients may have pain even when simply shaking hands. Those patients with a neuropraxia may also complain of intermettant numbness or tingling radiating into their fourth and fifth fingers. Sometimes, there is a history of an acute injury, e.g. throwing a curve ball, hitting a hard serve in tennis, or hitting a particularly jolting golf shot.
Physical examination will reveal tenderness over the anterior aspect of the medial epicondyle. Sometimes, this tenderness will extend toward the proximal flexor-pronator muscle mass just distal to the epicondyle. Pain is usually seen with resisted wrist flexion or resisted forearm pronation. Range of motion is usually unaffected. Those patients a neuropraxia may demonstrate decreased sensation in the ulnar nerve distribution, a positive elbow-flexion test, and a positive Tinel sign. In more severe cases, decreased sensation is associated with intrinsic weakness; intrinsic muscle atrophy may be noted. [5]
Since ME is not as common as LE, there are occasions when visualizing modalities are necessary. X-rays are useful to rule out arthritis or loose bodies. MRI may visualize pathology characteristic of chronic ME. MRI will also visualize the medial collateral ligament and ulnar nerve. Treatment of ME mirrors that of LE except that corticosteroid injection must be done very carefully because of the ulnar nerve.
Less common soft-tissue elbow injuries
In addition to LE and ME, there are a number of other chronic conditions involving the soft tissues of the elbow and the nerves that traverse its compartments. Biceps tendinosis is the result of microtrauma created by repetitive elbow flexion against resistance or repetitive forearm supination. Pronator syndrome is nerve entrapment of the median nerve. This can occur under a hypertrophied head of the pronator muscle, under the lacertus fibrosus at the elbow, or under the flexor digitorum superficialis. Radial tunnel syndrome is entrapment of the radial nerve. Triceps tendinosis is caused by repetitive elbow extension against resistance. Olecranon impingement syndrome is caused by repetitive elbow extension and valgus stress applied to the elbow. This is common in baseball pitchers and javelin throwers. [6]
In the pediatric age group, the classic problem of an overuse syndrome is little league elbow (LLE). The incidence of this particular injury has increased because of year-round training, very highly competitive participation at much younger ages, and conditioning and training errors.
Avulsion fractures of the medial epicondyle and ulnar collateral ligament (UCL) sprains or tears can also occur. Fractures often appear to be acute injuries, but they usually follow a period of increasing pain — indicative of the events of continued micro-injuries. Thus any thrower who experiences pain should refrain from activity. A medial epicondyle fracture will typically present as point tenderness and swelling over the medial epicondyle, UCL injuries can take the form of an acute event — the result of a particularly valgus stress. They can also appear as overuse sprains following. While this has many of the characteristics of LLE, it typically occurs in an older age group. Any athlete with a UCL injury should stop activity and be evaluated.
Lateral compression of the elbow can result in injuries to the capitellum and radial head. The capitellum may develop osteochondrosis, Panner disease, a condition most commonly seen in preadolescence. It presents as a dull ache in the lateral elbow that may be accompanied by swelling, clicking and a decreased range of motion. Rest will usually suffice to heal Panner disease. Osteochondritis dissecans (OCD) is also caused by repeated lateral compression. It is a localized injury of subchondral bone that may create loose bodies, capitellum deformity, flexion contractures, and degenerative disease of the elbow joint. Surgical intervention is sometimes required to correct this problem. This is a problem that most commonly occurs in the teen years.
Posterior problems, olecrenon injuries, are the result of repeated over-extension. They may present with clicking, posterior pain, and loss of extension.
While uncommon, it should be noted that lower cervical and upper thoracic neurological problems can present with elbow complaints and should remain a part of the differential. [7]
Elbow dislocations
While the elbow is an exceedingly stable joint, only dislocations of the finger and shoulder are more common. Because of the elbow’s stability, dislocations are usually associated with fractures. This is true approximately one third of the time. Dislocations without fractures are called simple fractures — those with fracture are called complex.
The most common direction for the elbow to dislocate is posteriorly. This usually results from a fall onto an extended and abducted elbow, the classic example being a skater who falls backward and attempts to break the fall. These dislocations do not usually involve neurovascular injury.
Anterior dislocations can occur following a direct blow to the posterior elbow. The net effect is to drive the olecranon forward relative to the humerus. This type of fracture is associated with neurovascular injury—to the brachial artery or the median nerve. This is an injury that requires immediate reduction. [8]
Patients with posterior dislocations present with the affected elbow in flexion. The olecranon is very exaggerated and on palpation displaced from the plane of the epicondyles. Patients with anterior dislocations present with the elbow in full extension. The upper arm arrears to be shorter than its contralateral partner—the forearm appears elongated.
At all times, the neurovascular status of the extremity should be monitored and documented. If there is a question of vascular compromise, an arteriogram may be needed.
Dislocated elbows require immediate reduction, and any dislocated elbow should initiate an emergency orthopedic consultation. If there is question about vascular compromise, a vascular surgery consult should also be initiated. [9]
Nursemaid's elbow
A common pediatric occurrence is nursemaid’s elbow. This is caused by slippage of the head of the radius under the annular ligament. This occurs because the annular ligament covering the radial head is weaker in children than in adults. This makes it more vulnerable to tear.
A typical history is of a child who suddenly refuses to use an arm. A history of a pull on the hand or wrist may be elicited but often is not volunteered. That history may be of a toddler held by the hand, the hand being pulled as the child and adult lurch in opposite directions, or a toddler is pulled by the wrist up and over an obstacle.
Examination reveals an anxious child protective of the affected arm. The arm is usually flexed and partially pronated. Tenderness at the head of the radius may be present. [10]
Reduction of the radial head is a relatively easy procedure that can even be done by parents.
showing procedure for reducing nursemaid's elbow
Fractures
The list of fractures or dislocations that can occur at the elbow include radial head fractures, olecrenon fractures, coronoid process fractures, distal humerus fractures, intercondylar fractures, condylar fractures, capitellum fractures, and elbow dislocations.
Radial head fractures
20% of elbow trauma involves a radial head fracture. Roughly a third of fractures and dislocations involve the radial head and/or neck. A fall onto an extended arm is the most common event that causes damage. The force of impact is carried up the hand through the wrist and forearm to the radial head. The head is then forced against the capitellum. Fractures may be divided into those just distal to the radial head and those involving the other structures of the elbow, distal humerus, or forearm and wrist.
The anatomic factor that complicates healing of radial head fractures is its intra-articular position. This means that the soft-tissue junctures to the upper end of the bone are limited. Since it is these attachments that carry blood supply, avascular necrosis and potential nonunion are common. This also means that removal of bone fragments is crucial to reduce posttraumatic arthritis from mechanical grinding. However, even with bone death, patients usually do well because of the limited function of the radial head.
At present, a surgical repair is indicated for all patients except those who have fractures stable enough to allow early motion. Over time, difficulties have developed with surgical excision of the radial head because of migration of the radius. This has even been a problem with replacement of the head with implants. Consequently, anatomic reduction and internal fixation is currently the treatment of choice. [11]
A Salter Harris II fracture is the most common type of fracture. Findings indicative of this fracture are the so called positive "sail" as well as posterior fat pad signs. A practitioner should look for anterior or posterior displacement of the radial head or shaft. A Monteggia equivalent is a fracture of the radial head along with an ulnar shaft fracture. [12]
Fractures of the ulna
The olecranon is a very heavy and strong structure, but it is fractured rather frequently in adults because of its prominent position on the point of the elbow. In addition, tremendous cross strain is imparted to the olecranon during falls on a flexed forearm. Children do not often experience olecranon fractures because in childhood, it is stronger than the lower end of the humerus.
The most common injury producing an olecranon fracture is a fall on a semiflexed supinated forearm. Muscles are tensed to protect against the fall, and as the hand hits the ground, the triceps muscle basically snaps the olecranon over the lower end of the humerus. Direct trauma to the point of the elbow and hyperextension can also produce fractures. Displacement of fracture fragments greater than 1.5 cm is uncommon. [14]
All fractures of the olecranon have some sort of intra-articular component. Because of this, they are usually accompanied by a hemarthrosis. This creates pain and swelling over the olecranon as well as an inability to extend the elbow against gravity. This is an indication of discontinuity of the triceps attachment. Presence or absence of this sign determines the course of treatment. [15]
Any patient with significant medical problems should have an olecranon fracture treated in a closed, conservative fashion. In patients with severe medical illness, steroid use, or dementia, even significantly displaced fractures can be treated non-surgically. The only treatment necessary is an Ace wrap with abundant padding. Extensor function may be compromised, but pain from non-union is rare.
In healthy patients, nondisplaced fractures with normal extensor function may be treated nonoperatively. Three weeks of casting is an average length of time. It is most convenient to immobilize the elbow at 90 degrees, but the elbow can be placed in any amount of flexion. Extension is often required for a reduction of displacement.
Significant displacement of greater than 2 mm or comminution sometimes require surgical intervention. Open reduction and internal fixation is the standard of care for displaced intra-articular fractures. [16]
Humerus fracture
Fractures of the distal humerus are the most complicated of all humerus fractures. A distal fracture can impair elbow function. At one time, these fractures were almost all treated through closed reduction—the so called “bag-of-bones” method. The goal of modern day open reduction is restoration of normal anatomy.
Fortunately, these fractures are relatively uncommon. They are estimated to make up about 4% of all fractures. The typical etiology for the fractures is a high-energy injury. However, in the pediatric population, particularly in boys aged 5 to 10 years-of-age, 80% of all elbow fractures occur in the supracondylar region.
The patient should initially be examined with attention to the presence of any other life -threatening injuries. When these have been ruled out, the injured extremity should first be examined for neurovascular integrity. This should be documented and an ongoing documentation should be established. This should include an assessment of the sensory and muscular contributions of the median, ulnar, and radial nerves, as well as the medial and lateral antebrachial cutaneous nerves. Distal pulses should be checked as well as capillary refilling. Duplex Doppler studies or angiography may be used in the case of equivocal findings.
Because in high-energy injuries open wounds often extend into the joint, wounds should be closely inspected. They should be treated with antibiotics and tetanus prophylaxis. The wound should be protected with a loose dressing of povidone-iodine. The elbow should be placed in slight flexion in a well-padded and molded splint. This will offer some pain relief until definitive treatment can be completed. The arm should be re-evaluated for neurovascular integrity on a regular basis. This should include attention to any signs of a compartment syndrome. [17]
When considering treatment options, it is now reasonably well established that open reduction and internal fixation of complex distal humeral fractures will result in favorable results in the majority of patients. However, a satisfactory outcome requires restoration of the structural integrity of the distal humerus, rigid stabilization of the fracture, and an early range of motion program. When these are achieved, excellent results can be expected in up to 75% of patients. An absence of any of the factors greatly increases the chances of a loss in elbow function. [18]
