Open Reduction and Internal Fixation of Diaphyseal Forearm Fractures

 

 

 

DEFINITION

Diaphyseal forearm fractures include isolated or combined radial and ulnar fractures (“both-bone fractures”). They occur distal to the elbow joint and proximal to the wrist joint.

It is critical to evaluate the distal radioulnar joint (DRUJ) and radiocapitellar joint preoperatively, intraoperatively, and postoperatively to avoid missing Galeazzi- and Monteggia-type injuries.

Fixation techniques should be tailored to the age of the patient and the location and pattern of fracture.

Excellent functional results and union rates can be obtained when skeletal length and alignment are restored with stable internal fixation.

 

 

ANATOMY

 

Complete knowledge of neural, vascular, and muscular anatomy is expected. Neural anatomy is particularly important, as a nerve injury in the forearm rarely completely recovers. Nerve injuries result in disabling, temporary or permanent, motor and sensory dysfunction in the hand.

 

Injury

 

 

Radial, posterior interosseous (PIN), median, anterior interosseous (AIN), and ulnar nerve injuries can all occur, although their incidence is not frequent. Preoperative nerve assessment is best performed by measurement of static two-point discrimination. Acutely, motor examinations are difficult secondary to pain. If a nerve injury is suspected preoperatively, that nerve must be explored within the zone of injury. Although the majority of nerves are found to be in continuity, the surgeon should be prepared to repair the nerve either primarily or with nerve cable grafts following bony stabilization.

 

Unless injured preoperatively, the radial, median, and ulnar nerves are not typically encountered. If they are encountered, this should alert the surgeon that he or she might be in the wrong dissection interval.

 

Muscle injury may be significant following fracture. It is typically not clinically significant except for injury to the flexor pollicis longus, which may even be nonfunctioning in severe injuries. This can be difficult to differentiate preoperatively from a partial AIN injury.

 

Approaches to the radius (FIG 1)

 

 

Five muscles cover the radius (supinator, flexor digitorum superficialis, pronator teres, flexor pollicis longus, pronator quadratus). When the soft tissue injury is significant, muscle size, fiber orientation, and tendinous insertions (particularly the pronator teres) help orient the surgeon. The supinator muscle is especially important to identify in both volar and posterior approaches to the radius to avoid injury to the PIN. Its fibers are obliquely oriented to the longitudinally oriented flexor and extensor muscles.

 

During the volar, or anterior, approach, the lateral antebrachial cutaneous nerve, superficial radial sensory

nerve, AIN, and PIN are usually encountered. The lateral antebrachial cutaneous nerve is sometimes encountered during blunt scissor dissection through the subcutaneous fat following the skin incision. Proximally, the superficial radial nerve lies deep to the brachioradialis. One must avoid placing self-retaining retractors on it.

 

The radial artery is encountered in every anterior approach to the radius. It is found deep to the brachioradialis in the proximal one-third of the forearm and visualized just beneath the forearm fascia exiting near the divergence of the brachioradialis and flexor carpi radialis muscle bellies in the midforearm. In very proximal volar approaches, near the bicipital tuberosity, crossing veins and the recurrent radial artery can be visualized.

 

Superficial veins of the volar and dorsal forearm can be large and contribute to significant bleeding. Formal suture ligation may be needed for large veins.

 

During the dorsal, or posterior, approach to the radius, the PIN and possibly the superficial radial sensory nerve may be encountered.

 

Approaches to the ulna (see FIG 1)

 

 

The dorsal ulnar cutaneous nerve is most commonly visualized passing in a volar to dorsal direction through the subcutaneous tissue, distal to the ulnar styloid. However, rarely, variations do exist where this nerve crosses the ulna more proximally. Therefore, blunt dissection through the subcutaneous fat in the distal

one-third of the forearm is safest for preventing inadvertent nerve injury.

 

The entire ulna is a subcutaneous bone, and subperiosteal dissection provides extensile exposure. Flexor carpi ulnaris and flexor carpi radialis border the volar and dorsal sides of the ulna. These muscles converge in the middle third of the ulna, requiring only shallow intramuscular dissection to expose the ulnar shaft.

 

Fixation

 

 

Both the AIN and PIN lay millimeters away from the radius in anterior and posterior approaches. Reduction clamps inadvertently

 

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placed around them when affixing a plate to the bone or reducing fracture fragments can damage them. Additionally, avoid using monopolar cautery on the ulnar aspect of the radius. When bleeding is encountered from the anterior interosseous vessels, they must be dissected away from the nerve prior to obtaining hemostasis to avoid nerve injury. Bleeding is stopped with bipolar cautery or small vascular clips.

 

 

 

FIG 1 • Muscular and neurovascular anatomy of the forearm. A. During a volar approach to the forearm, the radial artery, superficial radial nerve, anterior interosseus neurovascular structures, and posterior interosseous nerve may all be encountered. Detailed knowledge of their location and ability to visually identify these structures are critical to avoiding injury when their anatomic location is disrupted by injury. B. Dorsal approaches must demand identification of the posterior interosseious nerve proximally and superficial radIal nerve branches distally. During distal third ulnar approaches, the dorsal cutaneous branch of the ulnar nerve may be encountered notably when anatomy is aberrant.

 

 

Osteology

 

 

The radius has a complex osteology with both a radial and sagittal bow. The radial bow has an arc of approximately 10 degrees and lies in the coronal midshaft, whereas the sagittal bow has an approximately 5

degree arc and lies in the proximal third of the radius.9 Contouring of anteriorly placed plates on the proximal radius accommodates the sagittal bow. Anatomic plates are available to accommodate the radial bow.

 

The ulna is generally flat in the sagittal plane and curved in the coronal plane (with the exception of the

proximal ulna which in some patients has a slight apex posterior curvature at the olecranon).8 In the middle and distal thirds of the forearm, plate fixation can be placed anteriorly or posteriorly to avoid symptomatic hardware. In proximal ulnar shaft fractures, plate placement along the subcutaneous border, although possibly more symptomatic, obviates the need for plate contouring to the ulnar coronal bow. This placement also helps resist the forces generated during elbow flexion and extension from the long lever arm of the

forearm.

 

PATHOGENESIS

 

 

Direct trauma (guarding face against direct blow, gunshot wound) Indirect trauma (motor vehicle collision, falls)

 

The incidence of associated injuries in patients presenting to a trauma center with a both-bone forearm fracture is significant. In one series of 87 patients presenting to a regional

 

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trauma center, 40% had multiple injuries (25% with closed head injury, 26% associated major injuries in the same extremity).3

NATURAL HISTORY

 

Closed treatment of radius or both-bone forearm fractures generally yields unacceptable results.1

 

Plate fixation using 3.5-mm compression plates of radial and ulnar fractures is the standard of care yielding good or excellent functional results and union rates greater than 95%.3

 

Restoration of forearm rotation depends on obtaining proper skeletal length and axial and rotational alignment.11

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Evaluate for life-threatening injuries first.

 

When there is obvious injury to the forearm, it should be examined last so that satisfaction of search does not result in missed injuries.

 

Examination begins at the neck and shoulder girdle away from the injured area. In an awake, cooperative patient, palpation of each bony structure will typically reveal injury for which imaging should be obtained. In an uncooperative or intubated patient, a very low threshold for obtaining imaging is needed.

 

It is particularly important to palpate the radial head, collateral ligaments of the elbow, distal radius and ulna, and triangular fibrocartilage complex to avoid missing soft tissue, Monteggia, or Galeazzi injuries. If a ligamentous or tendinous injury is suspected in the setting of a stable joint, a magnetic resonance imaging (MRI) scan is ordered to make the diagnosis and allow for early repair if indicated.

 

Usually, obvious gross deformity is present when both the radius and ulna are fractured, but isolated radius or ulna fractures are easily missed especially in a polytrauma, intubated, or noncommunicative patient.

 

It is critical that the forearm compartments be visualized in their entirety and palpated to assess for compartment syndrome. All splints and dressings must be removed so the skin can be examined circumferentially. The signs and symptoms of compartment syndrome should be checked and documented even when they are “negative.”

 

The neurovascular examination at a minimum should include an assessment of radial and ulnar pulses and a detailed documented examination of the sensorimotor function of the median, radial, and ulnar nerves.

Preoperative AIN function should be documented as well.

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Anteroposterior and lateral radiographs of the forearm, wrist, and elbow generally suffice.

 

Careful scrutiny of the DRUJ and radiocapitellar joint alignment are performed on wrist and elbow radiographs.

 

In comminuted fractures, contralateral imaging of the uninjured forearm and wrist is helpful to determine the patient's native bony alignment and ulnar variance.

 

DIFFERENTIAL DIAGNOSIS

Radial shaft fracture with DRUJ injury (Galeazzi fracture)

Ulnar fracture with radiocapitellar dislocation (Monteggia fracture) Compartment syndrome

 

 

NONOPERATIVE MANAGEMENT

 

Nonoperative care is reserved for middle or distal third isolated ulnar fractures with no associated injury to the proximal radioulnar joint (PRUJ) or DRUJ. Proximal fractures are rarely treated nonoperatively.

 

 

Generally, greater than 50% of bony overlap and less than 15 degrees of angulation are appropriate for nonoperative management.

 

Distal fractures can be maintained in a fracture brace or short-arm cast. Midshaft fractures can be immobilized in “Munster cast” as described earlier or in a fracture brace.

 

The duration of immobilization is until pain subsides and the patient can tolerate mobilization. Weight bearing through the extremity is avoided until there is clinical and radiographic evidence of fracture union.

Early mobilization may lead to more rapid union.2

 

Rarely, stable isolated nondisplaced radius shaft fractures can be treated in a cast or functional brace that allows elbow flexion and extension but no forearm rotation.

 

Radiographic union can be expected between 8 and 10 weeks.

 

SURGICAL MANAGEMENT

 

The two primary goals of treatment are to obtain union and restore function. The primary surgical aim is the stable restoration of length, angular alignment, and rotational alignment.

 

Approach

 

 

Separate approaches are needed for the radius and ulna to minimize the risk of synostosis.

 

Radius fixation is performed through an anterior or a posterior approach. Anterior fixation minimizes but does not eliminate the possibility for symptomatic hardware. Anterior fixation is straightforward for middle-third and distal-third radius fractures but is more difficult in proximal-third fractures. The posterior approach has traditionally been recommended for the middle-third radius fracture but is rarely used. The posterior approach is most helpful during proximal radius exposure but care needs to be taken to protect the PIN.

 

The entire ulna can be exposed through a subcutaneous approach. Plate fixation can be on the subcutaneous surface, anterior surface, or dorsal surface.

 

Internal fixation

 

 

The order of operation in both-bone forearm fractures depends on the degree of comminution of each bone. Typically, the less comminuted bone is fixed first so as to have the most precise restoration of length.

 

Radius fractures are stabilized with the arm extended, whereas the ulna is typically stabilized with elbow flexed 90 degrees. Therefore, if indicated, radius fixation first allows a stable forearm during elbow flexion for ulnar fixation.

 

3.5-mm compression plates with six cortices of fixation on either side of the fracture are the standard of care. Anatomic and straight plates are available with locking and nonlocking screw options. Comminuted fractures may require bridge plating. Anatomic plates are very helpful for restoring the radial bow.

 

In osteoporotic fractures, the use of locking screws is indicated.

 

 

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Locked plates are also indicated when bridging a defect or when one segment is very short and six cortices of fixation cannot be achieved.

 

Care must be taken to ensure plates and screws placed on the both the distal ulna and the proximal radius does not impinge in each respective radioulnar joint. Locked unicortical screws must sometimes be used to avoid screw tip prominence in the joint. Live intraoperative fluoroscopic examination is used to assessing screw placement near the DRUJ or PRUJ. Additionally, it is critical to pronosupinate the forearm to ensure there is no plate impingement in these joints.

 

Bone grafting

 

 

Controversy exists regarding the role of acute autologous bone grafting. Use in the setting of comminuted segments of devascularized bone may be one indication.6,7

 

Closure

 

 

 

The tourniquet must always be taken down and meticulous hemostasis obtained. Fascia is left open and only skin and subcutaneous tissues are approximated.

 

When there is significant swelling that results in a tight closure, skin should be left open, and a delayed primary closure is usually obtainable after 72 hours.

 

Soft well-padded dressings with no tight circumferential wrapping minimize the risk of postoperative compartment syndrome.

 

Special circumstances

 

 

If the patient presents with signs and symptoms of compartment syndrome, they should be taken STAT to the operating room for decompressive fasciotomy of the forearm and carpal tunnel at a minimum. Typically, a single volar incision fasciotomy with release of superficial and deep fascial structures will suffice in decompressing the forearm compartments. Mobile wad and dorsal extensor compartments and hand compartments need to be critically evaluated following volar fasciotomy. They should be released if any suspicion exists for compartment syndrome of these compartments.

 

When large areas of bone loss are present, bridge plating is useful to keep the forearm bones out to the proper length. Consider using stainless steel plates, rather than titanium, because of their greater strength.

 

 

Dissection should be kept at a minimum in anticipation of further reconstruction, and if a vascularized bone graft is anticipated, no unnecessary vascular dissection should be performed in order to protect recipient arteries and veins needed for final reconstruction.

 

Preoperative Planning

 

Preoperatively, the surgeon needs to decide the approach and the type of fixation required.

 

Approach

 

 

Middle- and distal-third radius fractures are stabilized through a volar approach.

 

Proximal-third fractures can be stabilized through either a volar or posterior approach. Proximal-third fractures requiring exposure of the radial neck are approached dorsally.

 

Internal fixation

 

 

Plate selection for radius fractures depends on a variety of factors including the location of the fracture, fracture pattern, bone defects, quality of the bone, patient compliance, and size of the patient.

 

In proximal radius fractures, fixation of the proximal segment is frequently limited to two screws. The bone of the proximal radius near the radial tuberosity is more cancellous than cortical in nature, limiting screw purchase. Therefore, the use of locking plates and screws in the proximal segment can provide more reliable, stable internal fixation when the number of screws is limited. Additionally, when placed on the anterior radius surface, pronation must be evaluated for plate impingement between the ulna and biceps tendon at this level. A palpable clunk may be noted during pronation. If so, plate placement may need to be revised, but this can be difficult secondary to limited bone stock.

 

For simple pattern midshaft fractures, straight, small fragmentary 3.5-mm compression-type plates suffice with six cortices of fixation on each side of the fracture. A seven-hole plate is typically chosen with an open hole left over the fracture site (unless an interfragmentary screw can be placed through this hole).

 

Distal-third radius fractures can be stabilized with long periarticular volar locking plates, some of which incorporate a radial bow. Alternatively, small fragmentary 3.5-mm compression plates can be contoured distally to match the anterior metaphyseal curvature of the distal radius. Additionally, screw purchase in the cancellous distal radius may be poor, and placement of locking screws is sometimes helpful.

 

Positioning

 

The patient is placed supine with the injured arm out on a radiolucent arm table. A nonsterile pneumatic tourniquet is placed on the upper arm protected by a stockinette or padding. If acute autologous bone grafting is considered, the ipsilateral anterior iliac crest should be included in the surgical field.

 

Approach

 

For radius fractures, an anterior approach as described by Henry5 or posterior approach as described by Thompson10 may be used.

 

All radius fractures, except those extending to the radial neck and head, can be stabilized through a volar approach. One should consider the following when choosing an approach to the proximal radius:

 

 

In proximal fractures, there is more depth in the volar approach than the posterior approach, sometimes limiting visualization.

 

The volar approach is between the flexor mass as it comes to its confluence at the medial humerus and the biceps tendon insertion on the radial tuberosity. This limits the soft tissue mobility significantly again, sometimes limiting visualization.

 

Large caliber vascular structures and a network of tortuous veins make wide exposure of the bone more difficult in the volar approach.

 

After identification and protection of the PIN, the posterior approach provides wide exposure of the tension

side of the radius. Unfortunately, the PIN crosses the radius in proximal fractures, which make hardware placement more tedious and hardware removal, if needed, challenging.

 

 

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TECHNIQUES

• Anterior (Volar) Approach to the Radius

Light exsanguination is performed by elevation or loose wrapping with a sterile Ace wrap and the tourniquet is inflated.

The incision is drawn centered on the fracture from the lateral edge of the biceps tendon to the radial styloid. Length depends on the degree of comminution but in general will comprise approximately one-third of the forearm length (TECH FIG 1A).

An incision is made through the skin only, followed by blunt dissection down to the fascia. Attention is paid to visualization of the lateral antebrachial cutaneous nerve (TECH FIG 1B). (We generally score the skin with our knife blade then deepen the incision with a needle tip cautery through the dermis to aid in hemostasis at the skin level.)

Small branches of the lateral antebrachial cutaneous nerve if encountered are sacrificed to mobilize the main nerve out of the field of dissection.

A sponge can be used to sweep away the deep fat off the fascia if needed. The fascia is incised and released with scissors.

The radial artery and venae comitantes must be identified and mobilized. In the proximal third of the forearm, the radial artery lies deep to the brachioradialis muscle belly, which at this level nears the midline of the anterior forearm.

Bipolar cauterization of perforators to the brachioradialis muscle allows mobilization of the radial artery medially.

In the middle third of the forearm, the radial artery is more superficial—often in a layer of fat just beneath the fascia—as it exits the interval between brachioradialis muscle belly and flexor carpi radialis muscle belly (TECH FIG 1C). Again, the artery is mobilized medially.

In the distal third of the forearm, it is sometimes safer to mobilize the radial artery laterally, and in the very distal forearm, the approach can be made through the floor of the flexor carpi radialis, thereby avoiding the radial artery completely.

In the proximal forearm, the muscular envelope is deep, and dissection proceeds along the medial edge of brachioradialis.

The superficial radial nerve is identified, and care is taken not to place retractors directly on the nerve.

The supinator will be identified by the oblique muscle fiber orientation, and the surgeon must be mindful that the PIN runs proximal-medial to distal-lateral, entering 90 degrees to the orientation of the muscle fibers and fascia.

With the radius broken, it is difficult to effectively supinate the proximal forearm in order to protect the PIN.

If the bone is exposed distal to the supinator, a reduction forceps can be placed on the bone and the assistant can supinate the proximal radius. This allows the muscle to be peeled with a freer elevator or knife in a medial to lateral direction, safely keeping the PIN laterally.

Alternatively, the PIN can be identified, although this is usually not necessary.

 

 

When dissecting near the biceps tuberosity, usually, a small amount of clear, thick fluid from the biceps bursae will be released as dissection nears the biceps insertion. This burst of fluid is helpful in orienting the surgeon to their location. Just proximal to this, there are typically multiple crossing vessels that need not be disturbed. They can be retracted en masse with a blunt retractor if necessary.

 

 

 

TECH FIG 1 • Anterior approach to the radius. A. The forearm is mentally divided in thirds. Each third has unique anatomic structures that must be recognized during the approach. Extensile exposure extends from the biceps tendon to the radial styloid. Distal-third fractures can alternatively be approached through the floor of the flexor carpi radialis (FCR) tendon. B. Blunt dissection is performed superficially, and the main trunk of the lateral antebrachial cutaneous nerve (LABC) is identified and protected. (continued)

 

 

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The most efficient dissection to the middle and distal thirds of the radius proceeds down to its lateral border. Proximally, where the supinator lies the dissection on the medial radius avoids the PIN.

 

In the middle third of the radius, the flexor digitorum profundus and pronator teres can be sharply released from lateral to medial.

 

The pronator teres can be Z-lengthened or taken off the bone in a subperiosteal fashion. Alternatively, if only a limited amount of exposure is needed, its muscle fibers can be dissected off the tendinous portion for a short distance, leaving the tendon intact. If taken off the radius, it can be sutured back down to the plate (TECH FIG 1D). Our preference is the latter during extensile exposures.

 

 

 

TECH FIG 1 • (continued) C. In the middle third, the radial artery (Rad. Art) and venae comitantes are identified exiting between brachioradialis (Br) and flexor carpi radialis (FCR). Light exsanguination assists in identifying vascular structures. The superficial radial nerve (SRN) is seen coursing between Br and FCR. D. The upper images demonstrate the pronator teres (P.T.) insertion on the radius.

Middle image demonstrates drill hole placed through plate hole and radius for reattachment of P.T. (lower image). E. A segmental radius fracture and the AIN and vessel closely approximated to the proximal fragment. (continued)

 

 

Distally, the flexor pollicis longus and pronator quadratus are taken off the radius laterally to medially with a knife.

 

Bone fixation techniques are then performed as described in the following text (TECH FIG 1G).

 

The tourniquet is always taken down. If a meticulous dissection has been performed with liberal use of bipolar cautery, little bleeding is encountered.

 

Fascia is not closed, but inverted interrupted absorbable monofilament suture is used as needed to reapproximate the subcutaneous tissues followed by 3-0 nylon suture for the skin.

 

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TECH FIG 1 • (continued) F. Retraction of vessels with a Freer, allowing safe exposure of radius. G.

Anatomic plate fixation of the segmental radius fracture with restoration of the radial bow.

 

• Posterior Approach to the Radius

   

  The posterior approach is typically used for proximal- or middle-third radius shaft fractures. Extensile exposure of the entire proximal and middle thirds of the radius is described in the following text.

   

  An incision is drawn from the lateral epicondyle of the humerus to Lister tubercle and centered on the fracture.

   

  The incision length typically approximates one-third the length of the radius centered at the fracture (TECH FIG 2A).

   

  Blunt dissection is performed down to the level of the fascia, and small fasciocutaneous flaps are elevated. Perforating fasciocutaneous vessels can usually be seen and cauterized with a needle-tip cautery.

   

  Proximally, the interval lies between the white, thick tendinous band of the extensor digitorum communis tendon at the confluence of the extensor mass and the muscle belly of the extensor carpi radialis brevis just anterior to it (TECH FIG 2B).

   

  It is important to identify the tendinous origin of the extensor digitorum communis, as the radial portion of the lateral collateral ligament complex of the elbow lies directly deep to it.

   

  The fascia is incised just anterior to the white, thick tendinous band, and a Freer elevator is used to elevate the muscle fibers off the septum.

   

  The deep facial layer is then carefully opened with scissors in a distal to proximal direction revealing the supinator muscle, identified by the changing direction of muscle fibers proximal/posterior to distal/anterior (TECH FIG 2C).

   

  The PIN enters the supinator approximately 90 degrees to the orientation of its muscle fibers. By lifting the radial wrist extensors and brachioradialis off of the supinator with a blunt retractor, one can frequently identify the PIN entering the supinator.

   

  Alternatively, the PIN is identified distally and traced proximally through the supinator (TECH FIG

  2D,E).

   

  In the middle third of the radius, the abductor pollicis longus and extensor pollicis brevis are identified and elevated off the radius sharply for exposure.

   

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  TECH FIG 2 • Posterior approach to the radius. A. Extensile exposure (lateral humeral epicondyle to Lister tubercle). B. Proximal interval is located between extensor digitorum communis (EDC) and extensor carpi radialis brevis (ECRB). C. The deep fascia of ECRB and EDC has been divided, and the oblique fibers of the supinator are now visualized. The posterior interosseous nerve (PIN) can be seen entering supinator perpendicular to its fibers. (continued)

   

   

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  TECH FIG 2 • (continued) D. The supinator has been partially divided to reveal the PIN coursing through its substance. The radial head is seen proximally and the radius fracture is seen distally. E. A 3.5-mm locking compression plate has been applied to the proximal radius. In this case, only two screws of proximal fixation were available, therefore locking screws were used. F. Pre and postoperative radiographs demonstrating bridge plating of this comminuted proximal radius fracture. A 3.5-mm locking plate was utilized. Proximally, the plate placement must be scrutinized to avoid impingement during forearm pronosupination. In our experience, this fracture is at significant risk for infection and nonunion. Acute bone grafting was not performed secondary to concern for infection.

   

   

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• Approach to the Ulna

   

   

  The incision is drawn from the olecranon to the ulnar styloid centered on the fracture. After incision, blunt dissection down to the ulnar shaft is performed (TECH FIG 3A).

   

  In the distal third of the ulna, care must be taken not to injure the dorsal ulnar cutaneous nerve branch, which is typically found in the subcutaneous tissues just distal to the ulnar styloid, passing obliquely in a

  proximal-volar to distal-dorsal direction, obliquely to the dorsum of the hand. Rarely, it crosses the ulna more proximally.

   

   

   

  TECH FIG 3 • Approach to the ulna. A. Incision drawn along the ulnar subcutaneous border. B. Open reduction and internal fixation (ORIF) of the ulna with comminuted butterfly fragment with dorsal plate. C. Comminuted butterfly fragment and supplemental allograft bone graft fills the defect. (Autograft bone grafting for this type of defect may be preferred. This can be performed acutely in closed fractures if necessary.)

   

   

  Once the ulna has been identified, sharp dissection readily exposes bone needed for fracture reduction and stabilization as previously described (TECH FIG 3B,C).

• Fracture Reduction

   

  To stabilize transverse or short oblique fractures, the plate is applied on the distal fragment first affixing a far hole and then a near hole centered on the bony fragment.

   

  Next, the proximal fragment is reduced and held reduced with reduction forceps while standard compression screws are placed.

   

  A seven-hole, 3.5-mm compression plate with the open hole over the fracture site is typically used with three bicortical nonlocking screws placed on each side of the fracture.

   

  Consider overbending the plate slightly into a concave configuration to compress the side of the fracture opposite the plate.

   

  For transverse fractures with a butterfly fragment, our preference is to reduce and stabilize the butterfly fragment with a free screw outside the plate. Often, this screw may be a 2.4-mm cortical screw.

   

  Typically, a lag technique is not used unless the butterfly piece is large enough to accommodate two screws. The butterfly fragment is held reduced with a pointed reduction clamp and a bicortical screw is placed. A bicortical rather than lag screw is used to allow greater fixation in a small piece of bone that is already compressed using the clamp. If lag screw fixation is attempted and fails, it is usually impossible to affix the butterfly fragment.

   

  This turns a three-part fracture into a two-part fracture, which is stabilized as earlier except aggressive compression is avoided so as to not displace the previously fixed butterfly fragment.

   

  In our experience, even devascularized butterfly fragments typically unite when well fixed.

   

  Bridge plating using an anatomic plate is performed for comminuted fractures.

   

  Again, the plate is centered and fixed to the radius on one side of the comminuted segment. The assistant applies manual traction through the hand, and fluoroscopy is used until the desired length is achieved. The plate is then fixed to the other side of the comminuted segment.

   

  If pulling the traction and affixing the plate is too cumber-some, the radius and ulna are pinned together with a 1.6-mm or 2-mm smooth stainless steel pin near the DRUJ to maintain the desired ulnar variance while plate fixation to the distal segment is applied.

   

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  Full-length forearm or wrist films of the uninjured forearm in supination are very helpful in determining the correct bone length (intraoperative fluoroscopic imaging of the uninjured forearm and wrist can be used is preoperative imaging is not available). Ulnar variance is used a comparative marker of length.

   

  Long anatomic distal radius plates can be helpful for distal radial shaft fractures, particularly when bone quality is poor and more plate length is desired.

   

  If 3.5-mm compression plates are used on the volar distal radial shaft, the distal segment of the plate should be contoured to match the slope of the distal radius.

   

  Distally, the bone is cancellous in nature and cancellous-type screws may be preferred to gain better screw purchase.

   

  Despite the possibility of symptomatic hardware, proximal ulnar fractures are plated on the subcutaneous surface.

   

  This surface has minimal sagittal bow and better resists angular stresses of elbow flexion and extension.

   

  Middle- and distal-third ulnar fractures can be plated anteriorly or posteriorly.

   

  Again, the plate is typically affixed first to the more narrow fragment of the fracture. Next, the fracture is reduced and the other fragment is fixed using compression technique.

   

  Combination plates (3.5-mm dynamic tubular plate [DCP]— one-third tubular) are helpful in balancing fixation plate strength and prominent hardware concerns in distal-third ulnar fractures. In very distal ulnar fractures, 90-90 fixation with locking hand modular plates, 2.5 mm or larger, may be helpful.

   

  When longer plate constructs are used on the radius (as in bridge plating or in the presence of a butterfly fragment), care must be taken to restore the radial bow to ensure the recovery of normal forearm rotation.

   

  This may require either contouring of the plate chosen or use of an anatomic plate.

   

  PEARLS AND PITFALLS
  	Compartment ▪ Strictly avoid regional anesthetic when bony stabilization is done within the syndrome first several days from injury or when there is any significant swelling to avoid masking a compartment syndrome.

  • Never close the forearm fascia. Discuss preoperatively that the skin may need

   

  to be left open with planned delayed closure 2-3 days later.

  • If presenting with compartment syndrome, proceed with STAT decompressive fasciotomy, plating, primary closure of the ulnar wound, and delayed closure of the volar forearm wound.

     

    Light exsanguination

• Light exsanguination allows easy identification of vessels for mobilization and cauterization minimizing the risk of postoperative bleeding (see TECH FIG 1C,E).

   

  Transverse fractures

  • This fracture pattern is difficult to hold reduced with clamps: First, fix plate to one side of the fracture using the hole farthest from the fracture and then fix the plate using the hole closest to the fracture. Last, reduce the other fractured segment and continue with compression plating.

 

Oblique fractures with butterfly fragments

• Fix butterfly fragment to one side of fracture first to create a two-part fracture from a three-part fracture. If the fracture dictates that interfragmentary screws are best placed on the same surface of the bone as the plate, place them through the plate as to not interfere with plate placement on the bone.

   

  Comminuted fractures

  • Obtain contralateral x-rays to evaluate “normal” bony architecture and ulnar variance. Strongly consider anatomic plates to aid in fracture reduction and restoration of radial bow.

     

    Osteoporotic fractures

  • Consider longer than typical plate selection and liberal use of locking screws after compression is obtained.

     

    Restoring radial bow in posterior approaches

  • If anatomic plating is needed during a posterior approach, a straight compression plate can be manually contoured to the edge of an unused anatomic anterior plate to prior to its placement to obtain the proper bow.

 

POSTOPERATIVE CARE

 

Bulky, soft fan-folded dressings; loosely placed circumferential cast padding; and a sling are placed.

 

Active range of motion of the shoulder, elbow, forearm, wrist, and hand is encouraged. Supervised therapy is recommended with a focus on pronosupination, which is the most difficult motion to recover.

 

In patients with a lower pain tolerance, a long posterior splint that stabilizes the forearm in neutral but leaves the fingers free is placed. At the first postoperative visit, all immobilization is discontinued.

 

Supervised therapy is recommended for patients not demonstrating improvement with self-directed range-of-motion exercises.

 

OUTCOMES

Classically, Anderson and colleagues1 defined an excellent result as fracture union with less than a 10

 

degree loss of wrist or elbow motion and less than 25% loss of forearm rotation. They reported 54%

excellent results in compression plating of 106 both-bone fractures.1 Using the same criteria, Chapman and colleagues3 reported 86% excellent results in the treatment of both-bone fractures.

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Recently, Goldfarb and colleagues4 used the Disability of the Arm, Shoulder, and Hand (DASH) and the musculoskeletal functional attachment (MFA) validated outcome measures to assess functional outcomes of both-bone forearm fractures treated with 3.5-mm compression plates.

They reported that pronation was significantly reduced compared to the uninjured limb.

Additionally, the outcome questionnaires found a subjective decrease in function when the range of motion of the forearm and wrist were less than the contralateral limb. Overall, outcomes based on

DASH and MFA were considered good.4

 

 

 

COMPLICATIONS

Larger series demonstrate an approximate 2% rate of postoperative infection.3

Other postoperative complications include compartment syndrome, nerve injury, radioulnar synostosis, failure of fixation, and symptomatic hardware. Use of 4.5-mm compression plates has been associated

with a higher incidence of refracture following plate removal presumable from the larger holes.3

Nonunion is rare in simple pattern radius and ulnar shaft fracture. Those with segmental defects may go onto nonunion and need to be followed closely postoperatively. Smoking cessation and metabolic optimization may minimize nonunion development.

Rotational malunion of radius fractures will significantly limit pronosupination, which is very difficult to correct.

Superficial radial nerve parasthesias and dysthesias are not infrequent following radial shaft fracture fixation. These typically resolve and likely related to overretraction during anterior exposure.

Iatrogenic AIN injury can occur with the use of monopolar cautery along the ulnar border of the radius (bipolar cautery should be used).

Additionally, the nerve can be injured by the placement of reduction clamps around the radius if care is not taken to stay close to bone with the clamp.

Proximally placed volar radius plates can impinge between the radius, ulna, and biceps tendon. This may be discovered during intraoperative pronosupination testing.

Unfortunately, due to the limited bone stock, repositioning the plate once placed may not be possible. Planned hardware removal may be considered in these circumstances.

When distal periarticular plates are used, especially long plates, it is imperative the plate fully contact the bone because it can irritate the flexor tendons if it is off bone.

With no exceptions, the tourniquet must be taken down and meticulous hemostasis obtained.

Compartment syndrome can result from a bleeding subcutaneous vein even when the fascia is left open.

REFERENCES

1. Anderson LD, Sisk TD, Tooms RE, et al. Compression-plate fixation in acute diaphyseal fractures of the radius and ulna. J Bone Joint Surg Am 1975;57(3):287-297.

    

    

2. Cai XZ, Yan SG, Giddins G. A systematic review of the non-operative treatment of nightstick fractures of the ulna. J Bone Joint Surg Br 2013;95-B(7):952-959.

    

    

3. Chapman MW, Gordon JE, Zissimos AG. Compression-plate fixation of acute fractures of the diaphysis of the radius and ulna. J Bone Joint Surg Am 1989;71(2):159-169.

    

    

4. Goldfarb CA, Ricci WM, Tull F, et al. Functional outcome after fracture of both bones of the forearm. J Bone Joint Surg Br 2005; 87(3):374-379.

    

    

5. Henry AK. Extensile Exposure, ed 2. Baltimore: Williams & Wilkins, 1970.

    

    

6. Moed BR, Kellam JF, Foster RJ, et al. Immediate internal fixation of open fractures of the diaphysis of the forearm. J Bone Joint Surg Am 1986;68(7):1008-1017.

    

    

7. Ring D, Rhim R, Carpenter C, et al. Comminuted diaphyseal fractures of the radius and ulna: does bone grafting affect nonunion rate? J Trauma 2005;59:438-441.

    

    

8. Rouleau DM, Faber KJ, Athwal GS. The proximal ulna dorsal angulation: a radiographic study. J Shoulder Elbow Surg 2010;19(1):26-30.

    

    

9. Rupasinghe SL, Poon PC. Radius morphology and its effects on rotation with contoured and noncontoured plating of the proximal radius. J Shoulder Elbow Surg 2012;21:568-573.

    

    

10. Thompson JE. Anatomical methods of approach in operations on the long bones of the extremities. Ann Surg 1918;68:309-329.

     

     

11. Trousdale RT, Linscheid RL. Operative treatment of malunited fractures of the forearm. J Bone Joint Surg Am 1995;77(6):894-902.