Supracondylar Humerus Fractures Treatment & Management


Practice Essentials

Distal humerus fractures in adults are relatively uncommon injuries, representing only about 3% of all fractures in adults. In a study of 4536 consecutive fractures in adults seen in the Massachusetts General Hospital emergency department, only 0.31% were supracondylar (bicolumn) fractures of the distal humerus. Although these injuries are relatively rare, most orthopedic surgeons are called upon to evaluate and treat patients with these injuries and, therefore, must be equipped to achieve optimal outcomes. [123]

We live in a society with a growing elderly population and a young population in which extreme sports and high-speed motor transportation are popular; therefore, the incidence of these fractures is likely to increase. In young adults, most distal humerus fractures occur from high-energy trauma, sideswipe injuries, motor vehicle accidents, falls from heights, and gunshot wounds. In elderly persons with more osteoporotic bone, most of these injuries occur from falls.

The clinical presentation of a supracondylar humerus fracture (SCHF) is that of a painful swollen elbow that the patient is hesitant to move. The elbow may appear angulated and the upper extremity shortened. Open wounds may be present. Associated injuries in adjacent joints may be noted.

Radiographic evaluations should include standard anteroposterior (AP) and lateral films. With comminuted bicolumn fractures, repeat films following initial reduction or with longitudinal traction maintained often prove helpful. For complicated fractures, computed tomography (CT) also can be helpful with regard to surgical planning. If vascular compromise is evident, emergency arteriography is warranted. 

Numerous classification schemes have been devised to categorize and discuss supracondylar fractures. In 1936, Reich originally classified these fractures into T and Y variations. [4 In 1969, Riseborough and Raidin described four categories based on degree of displacement, comminution, and rotation. [5 As surgeons became more adept at surgical reduction and internal fixation, the Arbeitsgemeinschaft für Osteosynthesefragen–Association for the Study of Internal Fixation (AO-ASIF) group described a classification based on fracture pattern and degree of comminution (see Classification).

Surgical treatment of supracondylar fractures has evolved significantly over the past few decades. In the 1960s and 1970s, most surgeons condemned surgical treatment because of high failure rates with loss of fixation, nonunion, and elbow stiffness. The "bag of bones" treatment was used when bone quality or fracture pattern was not sufficient to gain stable fixation. This led to generally poor and unpredictable results.

In the 1970s, treatment began to shift from casting and the "bag of bones" technique to surgical intervention with limited internal fixation. Again, results generally were poor, owing to lack of adequate stabilization for early motion.

In the early 1980s, the AO-ASIF group reported good and excellent results in 27 of 39 patients with comminuted fractures of the distal humerus. These were by far the best results reported in the treatment of these difficult fractures at that time. This led to an increased enthusiasm for surgical reduction and fixation. Additional surgical approaches were developed, along with more versatile fixation hardware, leading to improved surgical results. The "bag of bones" approach has now largely been replaced by total elbow arthroplasty, allowing improved and more predictable results.

Anatomy

For proper evaluation, planning, and execution of surgical treatment of SCHFs, the surgeon must have a solid understanding of the relevant anatomy from both a functional and a surgical perspective. (See the images below.)

Supracondylar humerus fractures: anatomy. TrochleaSupracondylar humerus fractures: anatomy. Trochlea rests in 6-8º valgus in relation to humeral shaft.
Supracondylar humerus fractures: anatomy. When vieSupracondylar humerus fractures: anatomy. When viewed on end, trochlea resembles spool.

Functionally, the elbow joint behaves as a constrained hinge. The olecranon of the ulna articulates around the trochlea of the humerus. The trochlea normally is tilted in 4° of valgus in males and 8° of valgus in females, thus creating the carrying angle of the elbow. The trochlea also is externally rotated 3-8° from a line connecting the medial and lateral epicondyles, resulting in external rotation of the arm when the elbow is flexed 90°.

A second plane of motion occurs with the elbow joint in supination and the forearm in pronation; this range of motion (ROM) is allowed by the radial head articulation with the capitellum and the ulnar notch.

The surgical anatomy closely mirrors the functional anatomy. For stable elbow motion, the trochlea must be restored to its normal position, acting as a tie rod between the medial and lateral columns of the distal humerus. This forms the triangle of the distal humerus, which is crucial for stable elbow function (see the image below).

Supracondylar humerus fractures: anatomy. Note medSupracondylar humerus fractures: anatomy. Note medial and lateral columns, connected by trochlea, thus forming triangle of distal humerus. Also note location of sulcus for ulnar nerve in relation to placement of medial plate, as well as location of radial nerve sulcus in relation to proximal placement of plates.

Both columns must be securely attached to the trochlea. Every attempt should be made to restore the proper valgus tilt and external rotation of the trochlea so as to achieve stability, full motion, and a normal carrying angle. The coronoid is important to elbow stability and should be reduced and fixated if displaced.

The olecranon fossa, a very thin wafer of bone, does not require restoration if badly comminuted. If the medial and lateral columns can be securely fixated to the trochlea, early motion should be tolerated. The medial column diverges from the humeral shaft at approximately 45°, continues, and ends in the medial epicondyle. Because nothing articulates with the anteromedial epicondyle, the entire surface is available for internal fixation hardware. Care must be taken to protect and transfer the ulnar nerve anteriorly.

The lateral column diverges from the humeral shaft at approximately 20° and is largely cortical bone with a broad flat posterior surface; thus, it is ideal for plate placement. At the posterior capitellum, cancellous screws must be used to avoid interrupting the anterior capitellar cartilage. Biomechanical studies have demonstrated the strongest construct of fixation of bicondylar fractures to be a direct medial plate and posterolateral plate with screws directed at 90° angles. This provides the varus and valgus rotational stability to the construct, thus allowing early ROM.

Etiology

The mechanism by which SCHFs occur has been a topic of debate. Historically, the mechanism has been accepted to be an axial load on the elbow, with the olecranon acting as a wedge splitting the medial and lateral columns of the distal humerus. However, mechanical studies performed on cadavers have shown that supracondylar (bicolumn) fractures are more likely to be produced with the elbow flexed beyond 90°. The fracture pattern is related to the degree of elbow flexion and the direction and magnitude of the force applied.

Epidemiology

Single-column fractures are relatively rare and account for only 3-5% of distal humerus fractures. Lateral-column fractures are more common than medial-column fractures. These fractures represent the distal extent of the respective column, including a portion of the articular surface. These are described as high or low, depending on the proximal extent of the fracture line and the extent of joint surface involvement. Milch previously described these as medial or lateral condyle fractures. [6]

Bicolumn fractures are far more common distal humerus fractures. In some reports, these account for as many as 70% of distal humerus fractures in adults. These fractures involve disruption of both the medial and the lateral column, thus disrupting the humeral triangle and resulting in disassociation of the articular surface from the humeral shaft. Successful treatment is most challenging in these fractures.

Prognosis

Outcomes have improved dramatically over the past few decades as surgical technique and instrumentation have improved. Nevertheless, these patients must be informed early in their evaluation that the elbow probably will never be normal.

The goal is to provide a comfortable elbow that functions as near to normally as possible. Most activities of daily living require a flexion range of 30-130°, which allows eating and personal hygiene. Compensating for lack of extension will be easier than compensating for lack of flexion, and compensating for lack of pronation will be easier than compensating for lack of supination.

The final motion achieved appears to be related to the degree of initial trauma energy and to successful restoration of stability allowing early ROM. High-energy trauma (eg, gunshot wounds, sideswipe injuries, or injuries from motor vehicle accidents) results in more soft-tissue damage and increased scarring, which is more likely to result in restricted ROM.

Some reports indicate that capsular release performed at the time of initial fixation for these high-energy distal humerus fractures improves the long-term ROM. Flexion usually returns first, within 2-4 months, and final extension may progress up to 12 months after the injury. Use of dynamic extension splints in gaining final extension has been shown to be of some benefit.

Numerous outcome evaluation schemes are available, but in low-energy trauma, a successful outcome is generally considered to be a 15-140° arc of motion with full supination and pronation and no pain or minimal pain. In high-energy trauma, these results are more difficult to obtain. Activity-related pain is present in approximately 25% of patients; however, it does not appear to be directly correlated with the amount of initial energy of trauma or with final ROM.

Radiographs of type 3C distal humerus fracture 5 mRadiographs of type 3C distal humerus fracture 5 months after injury and fixation using olecranon osteotomy approach and medial and posterolateral plates. Range of motion, 10-140º without pain.

Farley et al studied outcomes in 444 children with SCHFs according to the type of treating orthopedic surgeon (pediatric or nonpediatric). [7 Outcome factors included the following:

  • Open reduction rate
  • Complications
  • Postoperative nerve injury
  • Repinning rate
  • Need for physical therapy
  • Residual nerve palsy at final follow-up

For severe fractures, significantly more fractures were treated with open reduction in the pediatric orthopedic surgeon group than in the nonpediatric group, but there were no other significant outcome differences between the two groups. [7]

A comparative study of techniques for treating SCHFs in children was carried out by Pescatori et al. 


History and Physical Examination

The clinical presentation of a supracondylar humerus fracture (SCHF) is that of a painful swollen elbow that the patient is hesitant to move. The elbow may appear angulated and the upper extremity shortened. Some series report that open wounds are present in as many as 30% of these fractures. Patient history includes a high-energy trauma or significant fall. Evaluate adjacent joints for associated injuries.

Neurovascular status must be carefully evaluated and monitored. Owing to the close proximity of the neurovascular structures, injury is not uncommon. If a deficiency is noted, carefully evaluate and document when it first became apparent, the degree of involvement, and possible progression. If it first appeared following manipulation or splint placement, consider remanipulation; if the deficiency does not resolve, urgently explore to evaluate possible nerve entrapment. Neurapraxias are not uncommon and generally resolve with restoration of normal alignment and lengths. In the author's experience, resolution has occurred up to 18 months after injury.

Radiographic evaluations (see Workup) should include standard anteroposterior (AP) and lateral films. With comminuted bicolumn fractures (type C3 in the Arbeitsgemeinschaft für Osteosynthesefragen–Association for the Study of Internal Fixation [AO-ASIF] classification; see Classification), repeat films following initial reduction or with longitudinal traction maintained often prove helpful in further defining articular fracture fragments. For complicated fractures, computed tomography (CT) also can be helpful with regard to surgical planning.

If vascular compromise is evident, obtain emergency arteriograms. If arterial disruption is present, obtain a vascular surgery consultation followed by immediate open reduction and internal fixation (ORIF) to provide skeletal stability and support of vascular reconstruction.

Classification

AO-ASIF classification

AO-ASIF type A fractures are extra-articular fractures and are further subclassified as follows:

  • A1 - Epicondylar avulsions
  • A2 - Supracondylar fractures
  • A3 - Supracondylar fractures with comminution

AO-ASIF type B fractures are unicondylar fractures and are further subclassified as follows:

  • B1 - Fracture of the lateral condyle
  • B2 - Fracture of the medial condyle
  • B3 - Tangential fracture of the condyle

AO-ASIF type C fractures are bicondylar fractures and are further subclassified as follows:

  • C1 - T-shaped or Y-shaped fractures
  • C2 - T-shaped or Y-shaped fractures with comminution of one or two pillars
  • C3 - Extensive comminution of the condyles and pillars

This classification remains somewhat deficient in describing the mechanically important concept of the medial and lateral columns and their fracture involvement. It also is somewhat deficient in describing the level through which the fracture occurs in each column and related important surgical considerations.

Mehne-Matta classification

In view of the aforementioned limitations of the AO-ASIF classification, the author believes that the classification of bicolumn fractures of the distal humerus introduced by Mehne and Matta proves useful in planning bicolumn surgical fixation.

The classification of Mehne and Matta describes the specific characteristics of bicolumn fractures and allows for better preoperative planning. [9The classification is as follows:

  • High T fracture
  • Low T fracture
  • Y fracture
  • H fracture
  • Medial lambda fracture
  • Lateral lambda fracture

Although the medial and lateral lambda fractures are not technically bicolumn fractures, they are included in this classification because they require similar operative fixation techniques.


Imaging Studies

Radiography

Adequate radiographs must be obtained to evaluate the fracture anatomy and to plan for surgical treatment. Radiography should include routine anteroposterior (AP) and lateral films, and possibly additional studies (eg, oblique views) as well. With comminuted bicolumn fractures (Arbeitsgemeinschaft für Osteosynthesefragen–Association for the Study of Internal Fixation [AO-ASIF] type C3), repeat films following initial reduction or with longitudinal traction maintained often prove helpful in further defining articular fracture fragments.

Silva et al studied the interobserver reliability (IEOR) and intraobserver reliability (IAOR) of the Baumann angle of the humerus (a simple, repeatable measurement that can determine outcome of supracondylar humerus fractures [SCHFs] in children). [10This angle was measured by five observers on AP radiographs of 35 elbows that had sustained a nondisplaced supracondylar humerus fracture.

Ranges of differences in the measurement of the Baumann angles were established, and the percentage of agreement between observers was then calculated. [10When the difference between observers in reported measurements of the Baumann angle was calculated to be within 7º of each other, at least four of the five observers agreed 100% of the time.

Heal et al evaluated the IEOR and IAOR of the Gartland radiographic classification for SCHFs in children. [11AP and lateral radiographs of 50 SCHFs were graded on two occasions by four orthopedic surgeons according to the Wilkins modification of the Gartland classification, with the following results:

  • Type I fractures - Poor agreement
  • Type II fractures - Fair to moderate agreement
  • Type III fractures and the flexion group - Good to very good agreement
  • Good to very good intraobserver agreement

The authors concluded that surgeons should treat pediatric SCHFs on the basis of degree of displacement rather than the Gartland classification. [11]

Computed tomography

Computed tomography (CT) can also be helpful in surgical planning for complicated fractures. When concern exists about vascular injury, arteriography can be beneficial.

Other Tests

In cases of neurologic injury, electromyography (EMG) generally is not helpful until approximately 3 months after injury, at which point it may serve as a helpful baseline for assessing progress.



Approach Considerations

The main goals of surgical treatment of supracondylar humerus fractures (SCHFs) are as follows:

  • Restore normal anatomy
  • Provide an optimal environment for healing
  • Provide pain relief through fracture stabilization
  • Allow early range-of-motion (ROM) exercises and prevent stiffness 

If these goals are met, the patient will have the best possibility of regaining optimal function.

Long-term results after surgical treatment of these complex fractures have improved, largely because of improved surgical technique in gaining stability to permit early motion. Adult elbows after such an injury are not tolerant of prolonged immobilization, and if arthrofibrosis occurs, regaining function becomes extremely difficult if not impossible. Therefore, the aim of surgery is to stabilize to mobilize.

Fractures in which stable reduction could not be obtained were previously treated with the "bag of bones" technique. In this technique, early ROM was allowed, without attempted reduction and fixation. This led to generally poor results, with limited motion, pain due to noncongruent joint surfaces and nonunions, and cosmetic deformity. Because of these poor results, this treatment has now been largely replaced by total elbow arthroplasty. [12]

Contraindications for surgical treatment with open reduction and internal fixation (ORIF) include severe osteopenia, making adequate stabilization impossible. An insensate or avascular arm, which cannot be restored, makes any surgical treatment short of amputation futile. This occurs in severe sideswipes, crush, or avulsion-type injuries.

As a general rule, attempts should be made to salvage the upper extremity; even a somewhat limited arm, if sensate, is functionally better than an upper-extremity prosthesis. Severe contamination or soft-tissue injury must be dealt with before final stabilization in order to provide an optimal environment for healing and lessen the likelihood of infection.

Treatment of these fractures is likely to continue to evolve. Primary total elbow arthroplasty is becoming increasingly accepted in elderly patients with severe osteopenia and limited functional demand. In limited series, good results have been reported. Fixation hardware, including lower-profile bioabsorbable plates and limited dissection application plates, will continue to stimulate interest. Methods of achieving better screw purchase in osteoporotic bone would also be a welcomed advancement.

Regardless of future technologic advancements, these fractures will continue to provide significant challenges to treating surgeons. If attention is paid to careful evaluation and preoperative planning, stable restoration of anatomy, and early motion, acceptable results can be achieved.

Surgical Therapy

Optimally, surgery should be performed within the first 72 hours following the injury. Further delay may be necessary in patients with multiple traumatic injuries or in patients who are unable to undergo anesthesia for other medical reasons. In these cases, the limb should be splinted in as nearly normal an anatomic position as possible and should be elevated or kept in sidearm olecranon traction.

Generally, unless an open injury, vascular compromise, or compartment syndrome is present, these fractures do not require emergency late-night surgery. Surgical treatment is best carried out by an experienced operating theater staff at a time when all staff members are functioning optimally. [13]

Initial debridement of open wounds or compartment releases must be performed urgently, but even in these cases, the patient can be returned to the oeprating theater during more optimal hours for definitive surgical fixation. In cases of vascular compromise, bony stability must be provided on an emergency basis to support and stabilize the vascular repair. In cases of severe polytrauma, temporary external fixation may be indicated for short-term stabilization before definitive fixation can be achieved. 

The choice of operative exposure depends on the fracture pattern and the surgeon's preference. This article describes the chevron olecranon osteotomy, the advantage of which is that it affords excellent exposure of the entire distal humerus and elbow joint. This procedure also allows stable fixation and early ROM. The author believes that the bony fixation performed in an olecranon osteotomy permits safer early ROM than a soft-tissue repair (eg, a triceps turndown exposure) would. Single-column fractures or fractures in which access to the articular surfaces is not necessary do not require such an extensive exposure.

Other exposures are briefly described below (see Alternative Approaches to Distal Humerus).

Preparation for surgery

Preoperative planning must include careful review of adequate radiographs. This aids in planning the surgical approach and in selecting proper hardware. If fracture anatomy and fragments are difficult to ascertain, radiographs in longitudinal traction, computed tomography (CT) scans, or both can be helpful.

General anesthesia most often is necessary to allow patient comfort and adequate time for the procedure. On occasion, axillary block can be used if the surgeon is confident that adequate time will be available to complete the procedure. A sterile arm tourniquet also should be available and can be used on the sterile field during the procedure if bleeding makes fragment identification and reduction difficult.

The author prefers supine positioning with the elbow flexed over a sterile towel roll on the patient's chest. This affords excellent posterior exposure, provides easy wound access for both the surgeon and a first assistant, and allows the use of a second assistant across the table to assist in retraction. The towel roll also can be used as a fulcrum to assist in obtaining length and in maintaining reduction during internal fixation.

The author also believes that the supine position yields better patient physiology and provides better anesthetic access. The supine position can be especially helpful in patients with multiple traumatic injuries. This position also allows easy access to the iliac crest if bone grafting is necessary.

The patient is given prophylactic antibiotics before induction of anesthesia. The arm is then prepared and draped in the usual sterile fashion; caution is employed to ensure exposure of the proximal third of the forearm distally and exposure to the axilla proximally.

Operative details

The arm is elevated and exsanguinated with an Esmarch bandage, and the tourniquet is inflated to approximately 250 mm Hg. An incision is made along the proximal 5 cm of the medial ulnar border, curving to the medial side of the olecranon and returning to the midline posteriorly to approximately 15-20 cm above the elbow joint (see the image below). If abrasions or wounds are present, the skin incision can be altered.

Incision is made along proximal 5 cm of medial ulnIncision is made along proximal 5 cm of medial ulnar border, curving to medial side of olecranon and returning to midline posteriorly to approximately 15-20 cm above elbow joint.

The first objective is exposure of the ulnar nerve, which often is not easily palpable, because of swelling and displaced landmarks. The nerve usually can be located more easily as it emerges from the triceps fascia just medial to the inner muscular septum. It then is traced distally and released from the cubital tunnel and into the flexor muscle mass, with care taken to avoid the motor branch to the flexor carpi ulnaris (FCU). Articular branches must be sacrificed for later anterior transposition. The nerve then is carefully retracted and protected with a vascular tape (see the image below).

Nerve is traced distally and released from cubitalNerve is traced distally and released from cubital tunnel and into flexor muscle mass; care is taken to avoid motor branch to flexor carpi ulnaris. Articular branches need to be sacrificed for later anterior transposition. Nerve then is carefully retracted and protected with vascular tape.

The olecranon is isolated, and a small incision is made in the medial or lateral capsule for passage of a probe into the trochlea to palpate the level of the coronoid process. The apex of the chevron osteotomy then is planned 3-5 mm proximal to the coronoid, with the apex directed distally. (This also will correlate with a point just proximal to the radioulnar articulation.) If the surgeon prefers to use tension band wires for the fixation, no predrilling is done. If the surgeon prefers fixation with an intramedullary screw, predrilling will assist later anatomic reduction and screw placement.

The cut is made with an oscillating saw and completed with a sharp osteotome to prevent damage to the articular surfaces. A gauze sponge can be inserted into the joint before osteotomy completion to protect the articular cartilage further. The olecranon, with the intact triceps insertion, is reflected posteriorly and covered with a moist sponge, allowing easy access to the entire supracondylar humerus and to joint surfaces (see the image below). If the fracture extends far proximally, great care must be taken in locating the radial nerve as it exits the spiral groove at the junction of the distal two thirds of the humerus.

Cut is made with oscillating saw and completed witCut is made with oscillating saw and completed with sharp osteotome to prevent damage to articular surfaces. Gauze sponge can be inserted into joint prior to osteotomy completion to further protect articular cartilage. Olecranon, with intact triceps insertion, is reflected posteriorly and covered with moist sponge, allowing easy access to entire supracondylar and to joint surfaces.

The next goal is reconstruction of the joint surfaces. Fragments often must be rotated and intercalated into position in cases of comminution and displacement. Large retinacular reduction forceps are helpful in maintaining medial-to-lateral compression once the fragments of the trochlea are aligned. Carefully placed interfragmentary compression screws can provide excellent stability, provided that purchase can be obtained on both medial and lateral fragments.

The author prefers to use 4.0 cannulated cancellous screws for this fixation and finds that washers can be helpful if the bone is osteoporotic. It is also helpful to pass one screw from medial to lateral and one from lateral to medial when possible. When placing these screws, take care to avoid penetrating the trochlear sulcus or olecranon fossa. In addition, consider the possibility of later plate placement, and place screws so they will not interfere with plate positioning.

The next step is to attach the medial and lateral columns to the trochlea. This is accomplished with 3.5-mm reconstruction plates that are of sufficient strength yet can be contoured readily. If possible, the plates are placed directly medial and posterolateral. The bony anatomy lends itself well to this construct, and this construct is strongest biomechanically.

The lateral plate is placed in the most distal position possible, almost abutting the articular cartilage of the capitellum. In this way, the distal screw is directed proximally, avoiding the articular cartilage and providing an interlocking construct. If the thin wafer of bone in the olecranon fossa is comminuted, it need not be reconstructed, provided that both columns can be attached securely to the trochlea, thus restoring the distal humeral triangle.

Concern has been raised with regard to both plates terminating at the same level proximally, owing to the possibility of a significant stress riser being created. Although the author is unaware of related reported complications, staggering the proximal extent of the plate slightly to decrease this potential risk makes sense biomechanically.

The olecranon is then replaced in its position and held, and the joint is put through ROM. Motion and stability are assessed. If the coronoid is fractured and posterior instability is present, it is reduced most easily and fixated before reduction of the olecranon osteotomy. The olecranon then is secured according to the surgeon's method of choice, with the goal of adequate stability for early ROM in mind.

The triceps fascia is closed, and the ulnar nerve is transposed anteriorly, either submuscularly or subcutaneously, depending on the patient's size and the surgeon's preference. The tourniquet is released, hemostasis is obtained, and the wound is closed in standard fashion.

Alternative approaches to distal humerus

Anterolateral

The anterolateral approach is an excellent approach for ORIF of the humeral shaft but is less often applied to the distal humerus. It utilizes the internervous plane between the brachialis (musculocutaneous nerve) and the brachioradialis (radial nerve). It is an extensile approach, both proximally and distally. Proximal extension can be connected with the deltopectoral approach of the proximal humerus; distal extension is connected with the incision for the anterior approach to the elbow and then the proximal forearm (Henry approach).  

The patient is positioned supine with a hand table on the operating side. The landmark for the incision is the lateral edge of the biceps brachii, centering on the fracture. In the superficial dissection, the lateral edge of the biceps brachii is identified along with the antebrachial cutaneous nerve, and the muscle and nerve are retracted medially to expose the brachialis and the brachioradialis. In the deep dissection, the fasciae overlying these muscle are incised, and the brachialis and the biceps brachii are retracted medially and the brachioradialis laterally to expose the humerus. [14]

Lateral

The lateral approach can be employed for ORIF of lateral condyle fractures and is sometimes used in treating lateral epicondylitis (tennis elbow). Surgical treatment of lateral epicondylitis has not yielded convincing results. This approach dissects between the triceps and the brachioradialis. Because both muscles are supplied by radial nerve, there is no internervous plane. 

The incision commonly used in this approach is a straight one made along the lateral supracondylar ridge. The lateral antebrachial cutaneous nerve can be seen in the superficial dissection. The plane between the brachioradialis and the triceps is incised in the deep dissection. To expose the lateral condyle, the common extensor origin can be released off the lateral humerus and the triceps elevated posteriorly.  

The lateral approach is not an extensile approach. Proximal extension of the approach is limited by the radial nerve crossing through the lateral intermuscular septum. Distal extension is limited but can be obtained by extending into the Kaplan approach (the interval between the extensor digitorum communis [EDC] and the extensor carpi radialis brevis [ECRB]) or the Kocher approach (between the anconeus and the extensor carpi ulnaris [ECU]) to the elbow. [14]

Orthogonal vs parallel plating

Distal humerus fractures (including supracondylar fractures) are often both comminuted and intra-articular.  Surgical intervention is indicated in most cases, and these fractures are often complicated by difficulties in fracture-site exposure, a limited amount of subchondral bone, comminution in the metaphyseal or articular region, and the presence of osteoporotic bone. [15  

The primary aim of surgery is to achieve a stable, pain-free, and functional joint by restoring bony and articular anatomy and allowing early ROM. Two of the most common methods of surgically managing distal humeral fractures are orthogonal (or perpendicular 90-90) plating and parallel plating.  

Orthogonal plating typically involves a medial plate on the medial column combined with a posterior plate on the lateral column. This method was proposed by the AO group with the aim of achieving maximal stability and allowing early ROM exercises, in the recognition that stiffness is often a major issue after elbow surgery.

The recommended technique included fixation of the articular fragments with screws and column stabilization with two plates at 90º angles to each another. The posterolateral plate can be positioned as distally as the posterior ridge of the capitellar articular surface, with posterior-to-anterior screws providing purchasing power in treating coronal plane fracture fragments. [1516  

Parallel plating uses a medial plate against the medial column and a lateral plate against the lateral column. The concept of such plating follows the principles of architecture, whereby two columns are anchored at the bases and joined together at the top. Long locking screws are designed to pass through a plate from one side and into a bone fragment on the opposite side that is also anchored onto the contralateral plate. [15 

Biomechanical studies that compared parallel plating with orthogonal plating (using cadaveric distal humeri or artificial bone models) have yielded contradictory outcomes. Neither method has been clearly identified as superior to the other. [1517181920 

Several high-quality clinical studies have yielded similar results. In a prospective randomized trial that included 67 patients, Lee et al found no clinical or radiologic difference between the two surgical approaches in terms of clinical outcome, operating time, time to union, or complication rate. [21 Shin et al, in a retrospective study of 38 cases of distal humerus fractures treated with the two surgical methods, found that both orthogonal and parallel plating provided adequate stability, ROM, and anatomic reconstruction for distal humerus fractures. [22 

Regardless of the orientation of the plates, it is clear that contoured locking plate designs perform far better than traditional nonlocking plates. The ultimate decision regarding plate orientations should be made by the surgeon after careful consideration of the specific requirements of the patient, the characteristics of the fracture, and the availability of equipment.

Postoperative Care

A posterior long arm splint is applied with the elbow at 60-90° of flexion, depending on the amount of swelling. The arm is elevated above the heart level, and finger and shoulder motion are encouraged. Intravenous antibiotics are continued for 24 hours postoperatively. If the patient is then comfortable on oral analgesics and is independent, discharge from the hospital is allowed.

Complications

Infection occurs at a rate of 0-6% in published cases, including open fractures. The rate of tardy ulnar nerve palsy has been reported to be as high as 15%, but the author believes that this percentage can be lowered by using routine anterior transposition of the ulnar nerve when hardware is placed medially.

Nonunion of the distal humerus is more common in cases of high-energy trauma or loss of fixation. Most of these patients require reoperation with enhanced fixation to alleviate symptoms. [23Nonunion of the olecranon osteotomy also has been reported, but this author believes it to be rare when the chevron osteotomy, which allows a greater bony surface and more stable fixation, is utilized.

Hardware irritation can occur secondary to plates and screws or fixation of the olecranon osteotomy, and it has been reported in as many as 50% of cases in some series. If severe, this condition requires removal of the hardware after union. The most common cause appears to be the hardware used for fixation of the olecranon osteotomy, which causes tenderness when the elbow rests on a hard surface. In the author's series, 30% of the patients later required removal of their tension band wire fixation of the olecranon osteotomy.

Loss of fixation necessitates investigation into its cause. Osteoporosis, inadequate placement of hardware, patient noncompliance, and infection all are potential etiologies. Treatment depends on the cause. If loss of fixation is due to severe osteoporosis or patient noncompliance, further casting to gain union at the expense of motion may be the best alternative. If the patient presents with increased pain, decreased ROM, and radiographic evidence of hardware breakage or loosening, nonunion can be expected if no intervention occurs. If loss of fixation occurs without infection, total elbow arthroplasty should be considered.

Iatrogenic nerve injuries after operative treatment of supracondylar fractures occur in as many as 3-4% of cases. [24]

Despite the advances in operating techniques and the development of fixation devices with contoured locking plates, the incidence of complications associated with operative intervention remains high. Residual stiffness of the elbow, nonunion, malunion, posttraumatic osteoarthritis, ulnar neuropathy, and overall functional disability continue to be adverse sequelae of the operative treatment of these difficult fractures.

Several articles have described the complications occurring after surgical fixation of distal humerus fractures. However, because of the complex anatomy, the variations in fracture patterns, and the differences in patient populations and functional demands, the exact complication rate and reoperation rate cannot be determined at present. [16252627]

Long-Term Monitoring

Patients typically are seen in the clinic 10-14 days postoperatively. At that visit, sutures are removed; if the wound is stable, the patient is placed in a hinged elbow orthosis (ROM brace), and protected active ROM is allowed. (See the image below.)

Between postoperative days 10 and 14, sutures are Between postoperative days 10 and 14, sutures are removed. If wound is stable, patient is placed in hinged elbow orthoses, and protected active range of motion is allowed. Passive assisted range of motion is allowed to point of discomfort, not pain. Importance of early range of motion to final outcome is well documented. Orthosis is worn until evidence (both clinical and radiographic) of fracture union is present, and then orthosis use is discontinued. This usually occurs 6-12 weeks postoperatively.

Passive assisted ROM is allowed to the point of discomfort, not to the point of pain. The importance of early ROM to final outcome has been well documented. The orthosis is worn until evidence (both clinical and radiographic) of fracture union is present, at which point orthosis use may be discontinued. This usually occurs 6-12 weeks postoperatively