Medial Humeral Condyle Fracture

The humerus is a bone in the arm. The distal humeral physis (also called the growth plate) is located between the humeral metaphysis proximally and the epiphysis distally. The distal humeral epiphysis is bordered proximally by the physeal growth plate and distally by its articular surface with the ulna and radius. The humeral metaphysis is the growing portion of the humerus that lies between the epiphysis and diaphysis (the shaft or central part of a long bone).[16, 17]

The medial condyle of the humerus is the medial column of the distal expansion of the humerus that includes the following:

• Trochlea
• Coronoid fossa
• Olecranon fossa
• Medial epicondyle
• Medial supracondyle ridge
• Medial metaphysis
• Groove for the ulnar nerve

The trochlea is the distal medial articulating end of the humerus, which acts as a pulley for the ulnar trochlear notch to rotate around as the elbow is flexed. The coronoid fossa is the depression on the anterior surface of the medial condyle proximal to the trochlea that accommodates the coronoid process of the ulna. The olecranon fossa is the depression on the posterior surface of the medial condyle proximal to the trochlea, which accommodates the olecranon of the ulna.

The medial epicondyle is a prominent palpable process that projects medially from the trochlea and is the point of origin of the pronator teres and the common flexor tendon, which includes the flexor carpi radialis (FCR), the palmaris longus, the flexor carpi ulnaris (FCU), and the flexor digitorum superficialis (FDS).[18]  The medial epicondyle is the origin of the medial collateral ligamentous complex (see the image below). The medial supracondyle ridge is a bony ridge that runs proximally on the medial humerus from the medial epicondyle.

Attachment of medial collateral ligament components is pictured.

The capitellum, a rounded ball of bone adjoining the trochlea laterally, is the distal lateral articulating end of the humerus that articulates with the radial head. The lateral epicondyle is a prominent palpable process that projects laterally from the capitellum and is the point of origin of the common extensor tendon. The lateral supracondyle ridge is a bony ridge that runs proximally on the lateral humerus from the lateral epicondyle. The ulnar nerve, which runs in close proximity to the medial epicondyle, often may be palpated as a rounded cord just posterior to this bony prominence.

The elbow joint is a hinge-type synovial joint formed where the distal end of the humerus articulates with the proximal ends of the radius and ulna. It is a uniaxial joint with movements of flexion and extension. Normal range of motion is from 0° (full extension) to 135° (full flexion). Most functions of the elbow require motion of 30-130°. Consequently, a 30° extension lag has little functional significance. The normal physiologic carrying angle of the elbow in the anatomic position (full supination and extension) is approximately 165-170° (10-15° of valgus angulation).

Flexion is produced by the brachialis (the main flexor muscle) and the brachioradialis. In supination, the biceps brachii also flexes this joint; in pronation, the pronator teres assists in flexion. Flexion is limited by the apposition of the anterior surfaces of the forearm and arm, by tension of the posterior arm muscles, and by the collateral ligaments.

Extension is produced by the triceps brachii and is assisted by gravity and the anconeus . Extension is limited by impingement of the olecranon of the ulna on the olecranon fossa of the humerus and by tension of the anterior muscles and collateral ligaments.

At birth, a single cartilaginous cap covers the distal end of the humerus. During development, four separate ossification centers form at different times, as follows:

• The capitellum is first and begins to ossify when the infant is aged 6-12 months
• The medial epicondyle is second to form when the child is aged 5-7 years
• The third center to ossify is the trochlea when the child is aged 7-12 years
• The last center to ossify is the lateral epicondyle when the child is aged 12-14 years

Further complicating this pattern of development, the trochlear ossification center is frequently composed of multiple irregularly sized foci that eventually coalesce into a single structure. The trochlear and capitellar ossification centers eventually fuse. The pattern of ossification at these multiple sites is highly variable.

In the developing elbow, fracture through the medial condyle involves part of the cartilaginous or partially ossified trochlea and the ossified medial epicondyle. With the insertion of the common flexor tendon of the forearm and the medial collateral ligament (MCL) on the medial epicondyle, the fracture fragment tends to rotate around the axis of the epicondyle and can present at various degrees of rotation. Complete rotation puts the fracture surface facing the anterior and medial side of the elbow, with the medial epicondyle pulled distally and the articular surface facing posteriorly and laterally.

In addition, the surrounding soft tissues can be torn, and there may be damage to the articular surface of the ulna. Damage to the articular capsule or MCL of the elbow may be present. The ulnar nerve and the vasculature surrounding the elbow joint are also at risk. The blood supply to the epiphysis enters with the attachment of the MCL and the common flexor tendon. Separation of these structures at the time of injury or at surgery may lead to avascular necrosis.

The medial epicondyle fragment is usually displaced distally, though at least two cases of displacement of the fragment proximally have been reported. The fracture line usually involves only the apophysis; however, occasionally a fragment of metaphyseal bone is found attached to the avulsed fragment. If the fragment is incarcerated within the joint, the fragment may become adherent to the coronoid process of the ulna. When the fragment is incarcerated within the joint, the universal finding is a thick fascial band that binds the ulnar nerve to the underlying muscle. This thick fascial band is responsible for ulnar nerve dysfunction, either acutely or as a late finding.

Other elbow fractures may be associated with medial epicondyle fractures, and care must be taken to recognize the full extent of the injury. Associated injuries include radial neck fractures, olecranon fractures, and coronoid process fractures.

Medial condyle fracture

The following three possible mechanisms for medial condyle fracture[2, 3, 4, 6, 7, 8, 9, 10, 12, 19] have been described:

• A fall on the palm of an outstretched arm, with the elbow forced into valgus (see the first image below)
• A fall on the point of the elbow (apex of the flexed elbow), with the olecranon driving the medial condyle proximally and medially (see the second image below)
• An avulsion fracture due to violent contraction of the flexor and pronator muscles that attach to the medial epicondyle, such as that which occurs in arm wrestling (see the third image below)

Valgus levering force creating fracture.

Olecranon acting as a wedge and creating medial condyle fracture.

Medial condyle fracture caused by traction through flexor pronator origin.

Medial epicondyle fracture

Three mechanisms of injury for medial epicondyle fractures[20, 21] have been proposed for an acute injury. All of them result in a partial or complete separation of the apophyseal fragment from the rest of the humerus.

The first mechanism of injury is a direct blow on the posterior medial aspect of the epicondyle that may be associated with fragmentation of the avulsed bone.

The second mechanism is a pure avulsion injury produced by the flexor muscles of the forearm (see the image below). This avulsion may occur in combination with a valgus stress that locks the elbow in extension. The classic example is the child that falls on the extended arm and hyperextends the wrist and fingers, placing more stress on the forearm flexors. The normal valgus angulation or carrying angle of the elbow tends to accentuate the forces responsible for the avulsion injury. This mechanism can also explain associated injuries, including a radial neck fracture with valgus angulation and greenstick fractures of the olecranon.

Epicondyle fractures can be caused by traction forces.

This second type of avulsion injury may be a pure muscular avulsion secondary to contraction of the forearm flexor musculature with an elbow flexed. This mechanism may be responsible for medial epicondyle fractures associated with arm wrestling and throwing a baseball.

The third mechanism proposed for medial epicondyle fracture is associated with a dislocation of the elbow (see the image below). In this mechanism, the ulnar collateral ligament (UCL) provides an avulsion force that causes the medial epicondyle to fail.

Elbow dislocation associated with medial epicondyle fracture. In this lateral view, fragment is marked with circle.

Fracture of the medial condyle is very rare, especially when compared to frequency of other elbow fractures. In one study, radiographs of 589 elbow fractures in children younger than 16 years were reviewed. The most common fractures were the supracondyle fracture (55%), radial neck fracture (14%), lateral humeral condyle fracture (12%), medial epicondyle fracture (8%), and olecranon fracture (7%).[22] No cases of medial condyle fracture were reported.[23]

Fractures of the medial condyle are so rare that they receive little coverage in most popular textbooks and may not be mentioned at all in others. The incidence is described in the literature as being no higher than 1-2% of all elbow injuries in children. As a consequence of this rarity, there is a risk that these fractures may be overlooked.[24]

Most displaced medial condyle fractures occur when the trochlea is not ossified completely. Various studies have cited different average ages (ie, 10, 11, 9.5, and 7 years). Although a child of any age can sustain this fracture, it is most common during the developing years (ie, in children aged 7-14 years).

Medial epicondyle fractures are much more common than medial condyle fractures. In a large combined series of 5228 fractures of the distal humerus, medial epicondyle fractures constituted 14.1% of all distal humeral fractures and 11.5% of all fractures occurring around the elbow. Medial epicondyle fractures are four times as likely to occur in males, and most cases occur in children aged 9-14 years. Peak incidence is in children aged 11-12 years. The reported incidence of association with elbow dislocation reaches 55% in some series, and the fragment may be incarcerated in the joint in approximately 15-18% of cases.[25]

Children younger than 5 years tend to have nondisplaced fractures and good results. Older children tend to have more severely displaced fractures that involve the partially developed trochlear ossification center. Good results are obtained in patients who are seen early after injury and who have adequate reduction and fixation of their fractures. In patients seen late, proper reduction and immobilization are necessary to achieve satisfactory results; however, this is usually more difficult to achieve. Preserving full range of motion (ROM) of the elbow depends on restoring the snug relation between the humerus and the ulna throughout the arc of motion.

Most children with medial epicondyle fractures treated either nonsurgically or surgically end up with good long-term functional results. Children with fracture displacement greater than 5 mm treated nonsurgically had results that were comparable to those of children who underwent surgical stabilization. Open reduction with internal fixation (ORIF) is required in children with medial epicondyle fractures and incarcerated fragments that block motion. Comminuted medial epicondyle fractures appear to do worse if the epicondyle is excised than if they are treated nonsurgically.

Medial condyle fracture

The patient usually presents with a recent history of a significant fall on an outstretched hand or directly on the apex of the flexed elbow. The elbow may be severely painful after this injury. Swelling,[26] deformity, and loss of function of the elbow may be present. Palpable crepitus may be present over the medial condyle. Elbow motion may be decreased as a consequence of swelling and pain. The patient often holds the elbow fixed at approximately 90° of flexion. The patient may present with medial dislocation of the forearm, referred to as a fracture dislocation.

Distal neurovascular changes may occur, especially in the ulnar nerve distribution. Other injuries may be present that are easier to detect, such as elbow dislocation or fracture of the radial head or olecranon, which may distract the physician from making the diagnosis of medial condyle fracture. A high index of suspicion for this type of injury concurrent with other elbow injuries can ensure timely diagnosis and treatment.[2, 3, 4, 6, 7, 8, 9, 10, 12, 19]

Medial epicondyle fracture

The presentation of a patient with a medial epicondyle fracture does not differ significantly from that of a patient with a medial condyle fracture, as described above. A through physical examination should include a valgus stress test to assess for instability of the anterior oblique band of the ulnar collateral ligament (UCL; see the image below). The test is performed with the patient supine and the arm abducted 90º. The shoulder and arm are externally rotated 90º, with the elbow flexed at least 15º to unlock the olecranon. Valgus stress is then placed through the elbow to assess for ligamentous instability.[20, 21]

Positioning for valgus stress radiograph.

Medial condyle fracture

Fracture of the medial condyle of the humerus is a rare injury. Isolated case reports appear in the literature. Although the medial condyle fracture has been described in the literature since the early 1800s, some controversy exists as to whether these were descriptions of true medial condyle fractures or whether they were really descriptions of the more common medial epicondyle fractures. Studies have reported greater numbers of medial condyle fractures in the literature; however, the overall incidence of these fractures remains quite low. Of all elbow fractures in children, medial condyle fractures are reported to account for fewer than 1%.[2, 3, 4, 5, 6, 7, 8, 9, 10, 19, 27]

In 1964, Milch proposed the first classification system for unicondylar humerus fractures.[28] The Milch system is based on the location of the fracture line in the distal humeral epiphysis. Milch first described an avulsion fracture due to a transverse valgus force. He then described a classification system for two types of fracture caused by longitudinal forces (see the image below).

Schematic of two types of medial condyle fractures, as described by Milch.

A Milch type I fracture splits the trochlear groove, leaving the lateral trochlear ridge intact. A Milch type II fracture splits the capitotrochlear sulcus in such a way that the lateral trochlear ridge is part of the fracture fragment (see image below for a depiction of the two types). A type II fracture is inherently unstable and is called a fracture dislocation.[5] The avulsion and type I fractures can be treated open or closed; however, more complex type II fractures should be treated only with open reduction and internal fixation (ORIF).[8]

In 1965, Kilfoyle combined his own experience with that of five colleagues to collect a total of 11 examples of medial condyle fracture and separated them into three types of injury (see the image below).[29]

Displacement patterns as described by Kilfoyle.

A Kilfoyle type I injury involves a greenstick fracture or crush of the medial condyle metaphysis down to, but not including, the physis; Kilfoyle also stated that these may actually be incomplete supracondyle or intracondyle fractures. A type II injury involves a fracture through the physeal plate and epiphysis without displacement or rotation. Type III is similar to type II but with moderate-to-severe displacement and rotation of the fracture fragment.

Medial epicondyle fracture

In 1818, Granger reported the first unequivocal description of a medial epicondyle fracture. Granger described a fracture that resolved rapidly and left little functional deficit. In the early 1900s, several authors recognized that the fracture was often associated with elbow dislocation and that the avulsed fragment could become entrapped within the joint.

In 1950, Smith dispelled many of the complications previously attributed to medial epicondyle fractures. Smith refuted the view that medial epicondyle fractures were associated with growth disturbance, pain and disability, weak elbow flexion, or ulnar nerve dysfunction and went on to prove his theories in his classic study. He concluded that fractures involving the medial epicondyle were relatively benign and were not associated with significant functional deficit.

Farsetti et al confirmed Smith's conclusions.[30] Even in 42 patients with isolated fractures of the medial epicondyle with displacement of 5-15 mm, no significant difference was found between those treated with ORIF and those treated nonsurgically. No universally accepted system exists for classification of medial epicondyle fractures.

No laboratory tests are indicated for the diagnosis of a fracture, though they may be necessary for preoperative clearance.[31]

Diagnosis is usually based on standard anteroposterior (AP) and lateral radiographs of the affected elbow (see the images below).[8, 16, 31, 32]

Anteroposterior view of displaced medial epicondyle fracture.

Elbow dislocation associated with medial epicondyle fracture. In this lateral view, fragment is marked with circle.

Distinguishing a fracture of the medial epicondyle (see the image below) from a fracture of the medial condyle can be difficult in the developing elbow.[2, 3, 4, 5, 6, 7, 8, 9, 32] Because cartilaginous structures are usually not visible radiographically, the exact location of injury may not be obvious. With its complicated and variable pattern of ossification, trauma to this region presents a difficult diagnostic challenge.

Medial epicondyle fracture.

Because the medial epicondyle lies largely outside the joint capsule, fractures of this structure usually do not produce distention of the capsule. Therefore, if a positive fat-pad sign accompanies soft-tissue swelling, fracture extension distally into the joint capsule to include the trochlear ossification center and medial condyle should be considered.

Radiographic clues to unstable medial condyle fracture in a young child include soft-tissue swelling, a chip or flake of bone from the metaphysis, and the presence of a positive fat-pad sign.[32]

In slightly displaced or nondisplaced fractures of the medial epiphysis, widening or irregularity of the apophyseal physis may be the only sign. If the medial epiphysis is absent, the fragment may be incarcerated totally into the joint or hidden by the overlying ulnar or distal humerus.

The lack of a fat-pad sign cannot be used to exclude medial condyle injury. If the joint capsule is ruptured, no fat-pad sign is exhibited. Therefore, it may be necessary to examine the elbow under anesthesia to determine whether instability is present that would indicate a more extensive injury.

A widely displaced fracture-separation of the medial epicondyle in a patient whose trochlear ossification center has not yet appeared can indicate that the cartilaginous trochlea may also be fractured and attached to the epicondyle. This possibility should be considered and may warrant surgical exploration.

Arthrography may be used to determine the extent of a fracture and to help distinguish an epicondyle fracture from a condyle fracture.[33]

Magnetic resonance imaging (MRI) may be used to evaluate soft-tissue injury and may be helpful in evaluating cartilaginous injury.[34]

Interobserver and intraobserver reliability is poor for the use of plain radiography to assess epicondyle displacement.[35] Three-dimensional computed tomography (CT) is a more accurate means of evaluating displacement of an epicondylar fragment; indeed, plain films may underestimate displacement by up to 1 cm.[36]

Treatment indications

Salter-Harris type IV medial condyle fractures with 2 mm or more of displacement usually must be treated by means of open reduction with internal fixation (ORIF). A displaced medial condyle fragment or instability of the fragment with closed reduction is an indication for open reduction with rigid internal fixation. Accurate apposition of the fracture surfaces is important to reduce the risk of growth-plate disturbance and to prevent loss of motion due to articular incongruence. Nondisplaced medial condyle fractures can be treated without surgery.

For nondisplaced or minimally displaced medial epicondyle fractures, nonoperative management is the procedure of choice. More controversy exists with displacement of 5-15 mm. Similar functional results have been reported with operative and nonoperative surgical management. Long-term functional assessment has demonstrated similar results even with radiographic nonunion being apparent on most of the fractures treated nonoperatively.

Irreducible incarceration of the medial epicondyle fragment[37, 38] and open fracture are indications for operative management. Excision of the comminuted medial epicondyle fragment has been associated with less beneficial results.[39] Other controversial relative surgical indications include complete ulnar nerve dysfunction after an injury or reduction attempt and valgus instability in high-demand athletes.[20, 21, 40]

If the patient is unable to tolerate a long surgical procedure because of polytrauma, closed reduction and cast immobilization with 90° of flexion is an option.

Areas of controversy

Some authors have advocated routine ulnar nerve transposition, whereas others have maintained that this is unnecessary unless the ulnar nerve has been injured.

There has been disagreement regarding how to manage a fracture that has remained untreated for several weeks or longer. Formation of callus and fibrous tissue may obliterate the fracture site and cause a malunion that makes accurate dissection and reduction less accurate. Misdiagnosis or inadequate early treatment increases the risk of complications such as loss of movement and angulation.

Some have suggested conservative treatment for fractures older than 4 weeks, whereas others have demonstrated some restored function in treating these fractures at the time of delayed diagnosis, though the results are imperfect. Supracondyle wedge osteotomy has been advocated to restore anatomic angulation and motion loss from previous injury. Whether this is best performed during growth or after the physis has closed has not yet been determined.

The major controversy involving medial epicondyle fractures has involved the management of displaced fractures.[41] Good results have been reported with both operative and nonoperative treatment of the displaced medial epicondyle fracture. Some have advocated operative treatment of high-demand athletes, on the grounds that even minor amounts of valgus instability can result in significant disability. Others have recommended nonsurgical management, on the grounds that several long-term studies appeared not to substantiate significant valgus instability, even in individuals who went on to have radiographic nonunion of the epicondyle.

Closed reduction with cast immobilization is adequate for nondisplaced stable medial condyle fractures. Medial epicondyle fractures also may be treated in a closed fashion if the medial epicondyle is nondisplaced, minimally displaced, or even displaced up to 15 mm (see the image below).

Anteroposterior view of displaced medial epicondyle fracture after reduction.

Elbow dislocation associated with medial epicondyle fracture. Lateral view after reduction. Reduced fragment is marked. Note normal location somewhat posteriorly on distal humerus.

In many studies, including long-term follow-up reports, patients treated nonsurgically had results similar to those of patients treated surgically, even for fracture fragments displaced as much as 15 mm. A radiographic nonunion of the medial epicondyle fracture fragment associated with nonsurgical treatment was not found to have any functional impairment in at least one long-term study.[2, 3, 4, 6, 7, 8, 9, 10, 12, 31]

The only absolute indications for operative management of closed medial epicondyle fractures are the following:

• Incarceration of the medial epicondyle fragment within the joint
• Open fracture

An incarcerated fragment within the joint must be removed. Several closed means of reduction can be used, and the success rate with these methods approaches 40%. One such maneuver (the Roberts manipulative technique) is performed under sedation and involves placing a valgus stress on the elbow while supinating the forearm and simultaneously dorsiflexing the wrist and fingers to place the forearm flexor muscles on stretch. If employed, this maneuver is usually performed in the operating room with the patient under general anesthesia. Joint distention techniques also have been described to help facilitate closed reduction of the incarcerated medial epicondyle fracture.[20, 21, 40]

Initially, the arm should be splinted in 90° of elbow flexion. Gentle active range-of-motion (ROM) exercises may begin within 1 week after injury. Protective splinting may be continued for 3 weeks if necessary.

In preparation for ORIF, the arm is placed in a posterior splint for stabilization, elevated, and treated with ice packs to decrease swelling.

Medial condyle fracture

A medial approach may be used. A longitudinal incision is made over the medial supracondyle ridge of the humerus and continued just distal to the medial condyle. Branches of the medial antebrachial cutaneous nerve should be identified and preserved. The ulnar nerve is identified and protected and may be transposed anteriorly. The fracture surfaces are identified and cleaned, and the joint space is cleaned and irrigated to remove loose particles.

The condyle fragment is then reduced and secured at a minimum of two sites to prevent rotation. Kirschner wires (K-wires) or cancellous screws may be used. Plate-and-screw fixation is another option. The reduction should be confirmed radiographically. The wound is closed, and the arm is splinted in 90° of flexion with the forearm in the neutral position.[2, 3, 4, 6, 7, 8, 9, 10, 12, 31, 42]

Medial epicondyle fracture

A longitudinal incision is made just anterior to the medial epicondyle. The fragment is usually displaced distally and anteriorly. As with any fracture reduction, periosteum and bone fragments are cleared from the fracture site to allow anatomic reduction. The ulnar nerve must be identified and protected; ulnar nerve transposition is usually unnecessary. With the elbow flexed and pronated, the fracture fragment is reduced and pinned with one or two K-wires. A lag screw is then placed to maintain and compress the fracture fragment. Elbow stability and ROM are assessed. A posterior splint is then applied for at least 7-10 days until ROM is initiated.[20, 21, 40, 31, 42]

Elbow dislocation associated with medial epicondyle fracture. Anteroposterior view after fixation.

If the epicondyle is fragmented, excision of the fragment and fixation of the flexor-pronator origin and medial collateral ligament (MCL) to bone with an alternative form of fixation (eg, suture anchors) may be used. Excision of the fragment does not appear to yield results comparable to those of nonoperative treatment.

Ergin et al, in a long-term (median, 10 years; range, 5-15) comparative study of 42 children with displaced medial epicondyle fractures of the humerus, assessed internal fixation with K-wires (group A; n = 22) vs cannulated screws (group B; n = 20).[43]  The Mayo Elbow Performance Score (MEPS) was used to assess clinical outcomes, in addition to elbow ROM at the last follow-up. Median MEPS scores were 95 in group A and 94 in group B. No significant differences in ROM were observed. The authors concluded that favorable clinical and radiologic outcomes at long-term follow-up may be achievable by using two smooth K-wires for younger children and screw fixation for children near skeletal maturity.

With all degrees of injury, immobilization must continue until solid union is demonstrated. Radiography must be repeated until the union is ensured. This may be as early as 3 weeks for nondisplaced fractures and is usually about 6 weeks (occasionally as long as several months) for displaced fractures. This immobilization must be balanced against the need for physical therapy to prevent loss of ROM.

For fractures treated with ORIF, the arm should be put in a cast in 90° of flexion for 3 weeks and then placed in a posterior mold for 3 weeks with supervised active flexion and extension out of the mold. Internal fixation allows this early physical therapy to be instituted without compromising the reduction. Active ROM with physical therapist supervision is critical to prevent excess loss of flexion and extension. Passive ROM should be avoided because it can result in damage to contracted soft tissues and has been associated with myositis ossificans.

Late follow-up should be considered to screen for growth disturbance after injury to the epiphysis.

Medial condyle fracture

Nonunion[44] with a thickening deformity at the fracture site can occur with inadequate reduction, fixation, or immobilization. Catgut suture as a means of internal fixation has proved to be inadequate, in that it has often resulted in this complication. Malunion can result in loss of motion or angulation. As with nonunion, this can result from inadequate fixation or premature mobilization.

Some minor loss of motion (flexion and extension) is a common sequela of many displaced medial condyle fractures. The degree of loss is usually minimal and does not decrease function. When the loss is related to another complication, such as nonunion, malunion, or heterotopic ossification, it can be significant.

A progressive cubitus varus deformity may develop as a consequence of growth inhibition or avascular necrosis (AVN) of the medial humeral condyle. This also can result from premature closure of the physis. In one case, 40º of varus angulation was reported that went untreated for 4 years. This was treated with a supracondylar wedge osteotomy to restore ROM and correct the cubitus varus deformity.

AVN of the epiphysis can be the result of loss of blood supply during an overaggressive soft-tissue dissection in attempts to achieve adequate exposure of the fracture. The blood supply to the epiphysis is through the soft-tissue attachments at the medial epicondyle. A valgus deformity also can result from imperfect restoration of position. This is usually related to an overgrowth of the medial condyle.

Heterotopic ossification can result in severe loss of flexion and extension. This is often associated with delayed fixation and closed head injuries. Myositis ossificans can result from overaggressive physical therapy with passive ROM.

Pronation and supination are usually not affected. Concurrent injury to the radial head may result in decreased motion. Injury to the ulnar nerve may result in a partial clawhand, muscle weakness, and partial loss of sensation. If necessary, transposition of the nerve can be performed to reduce tension and prevent further injury. Partial or complete recovery may take months.

Misdiagnosis or delay in diagnosis or treatment increases the risk of impairment and complications.

Medial epicondyle fracture

The two main complications associated with medial epicondyle fractures are as follows:

• Failure to recognize incarceration into the joint with functional loss
• Ulnar or median nerve dysfunction

The first major complication with an unrecognized medial epicondyle fracture involves loss of motion secondary to impingement of the fragment. The second involves ulnar nerve dysfunction, which may occur in 10-16% of cases. If the fragment is incarcerated in the joint, the incidence of ulnar nerve dysfunction can reach 50%. More profound ulnar nerve dysfunction has been observed to occur with manipulative reduction attempts, especially if closed manipulation of an incarcerated fragment is attempted. A median nerve injury may occur as well; however, this is more common with an associated elbow dislocation.

Most of the other complications associated with medial epicondyle fractures are considered minor and do not result in a loss of function. These minor complications include radiographic nonunion of the medial epicondyle fragment in cases in which the fracture is treated closed. Functionally, no limitation from this radiographic finding appears to exist. A loss of elbow extension of 10-15% can be expected in up to 20% of cases, and this appears to be correlated more with prolonged immobilization than the fracture itself.

Myositis ossificans has been described as a rare occurrence and has been correlated with repeated manipulation to reduce an incarcerated fragment. A significant alteration in the carrying angle of the elbow has not been demonstrated in long-term studies and does not appear to be a major issue with these fractures.