Forearm Fractures Treatment & Management

All displaced adult forearm fractures should be stabilized because no other means of management is available that provides a comparable result. The following are specific indications for operative treatment:

• Fracture of both bones (ie, radius and ulna)
• Fracture dislocations, Monteggia fracture dislocations, and Galeazzi fracture dislocations
• Isolated radius fractures
• Displaced ulnar shaft fractures
• Delayed union or nonunion
• Open fractures
• Fractures associated with a compartment syndrome, irrespective of the extent of displacement
• Multiple fractures in the same extremity, segmental fractures, and floating elbow
• Pathologic fractures

If the patient is medically fit, there are few contraindications for operative fixation of a forearm fracture. Highly contaminated compound fractures, particularly with bone loss, may be managed with temporary external fixation followed by debridement and delayed internal fixation.

In children, the usual plan is to attempt closed reduction followed by cast immobilization. ^{[25, 2, 26]} There does not appear to be a significant difference between a single sugar-tong splint and a long arm cast in this setting. ^[27] Childhood obesity appears to increase the risk of malreduction and subsequent manipulations with closed reduction and casting. ^{[28, 29]}

In adults, treatment with immobilization in a molded long arm cast can be used in those rare occasions of a nondisplaced fracture of both bones of the forearm.

The cast should be applied with the elbow in 90° flexion. The stable position of pronation or supination can be found by screening on the image intensifier, but in general, fractures of the proximal third are stable in supination, fractures of the middle third are stable in neutral position, and fractures of the distal third are stable in pronation. Follow-up of these patients with radiography in both planes at weekly intervals for the first 4 weeks is mandatory to detect early displacement of the fracture.

Sarmiento et al reported the results of a closed method of treatment for nondisplaced fractures of one or both bones of the forearm. ^[30] Only in children does the salubrious effect of growth and remodeling offer an alternative to the otherwise mandatory surgical treatment of displaced or unstable forearm fractures, on the assumption that adequate alignment and proper rotation of the fragments can be obtained and maintained by closed methods.

Angulation in the plane of joint movement is most likely to improve with growth and remodeling. However, rotational deformity and loss of normal interosseous space cannot be expected to improve with growth and remodeling, even in very young patients.

The cutoff ages are in the range of 10-12 years in girls and 12-14 years in boys. At these ages, surgical treatment must be strongly considered for displaced fractures of the forearm. Children aged 10 years or older with proximal-third radius fractures and ulna angulation less than 15º seem to be at highest risk for failure when treated nonoperatively for both-bone forearm fractures. ^[31]

Open reduction and internal fixation

When both bones of the forearm are fractured, they are both exposed and provisionally reduced before fixation of either bone is completed. The fracture with the least comminution (usually the ulna) is fixed first. After reduction and provisional fixation of both bones, pronation and supination are examined; if normal, definitive fixation is performed.

The plate must be accurately centered over the reduced fracture and must be of sufficient length to permit, preferably, six cortices to be secured by screws on each side of the fracture (see the image below). The plates should be contoured to fit the bone, especially the radius, to maintain the normal bow of the radius for restoration of normal function. ^{[32, 33]}

The general rule is that bone grafting is recommended when more than one third of the circumference of the bone is comminuted. If this is instituted, it should be performed away from the interosseous membrane to decrease the risk of synostosis. In their review of 198 forearm fractures, Wright et al reported comparable results in union in comminuted forearm fractures treated with bone grafting and without bone grafting. ^[34]

In a study of 59 cases of shaft fracture of both forearm bones, Kim et al suggested that a combination of plate fixation and intramedullary nailing, though not generally preferable to plate fixation alone, might be a useful option for these fractures when treatment with plating by itself is not feasible. ^[35]

Intramedullary nailing

The first widely used and successful medullary forearm nail system was developed by Sage in 1959. ^[14] The prebent radial nail maintains the radial bow, and the triangular cross-sectional shape prevents rotational instability (see the image below).

When intramedullary devices are used in persons with a fracture of both bones, fixation of the radius must be stable enough to prevent collapse of the radial bow; otherwise, elongation of the radius and distraction of the ulnar fracture can occur, resulting in nonunion in either or both bones.

The entry point for intramedullary nailing of the ulna is made in the proximal ulna. The radial portal is usually into the radial styloid process between the extensor carpi radialis longus (ECRL) and the extensor pollicis brevis (EPB). All radial nails should be well seated to avoid fraying of the tendon and possible rupture. ^{[36, 37, 38]}

The indications for intramedullary nailing are as follows:

• Segmental fractures
• Poor skin condition
• Selected nonunions or failed compression platings ^{[39, 40]}
• Multiple injuries
• Diaphyseal fractures in osteopenic patients

Open forearm fractures

The traditional practice was to refrain from using internal fixation initially in open fractures of the forearm; initial management was with irrigation and debridement. Subsequently, treatment trends shifted toward initiating immediate open reduction and internal fixation (ORIF) of all open forearm fractures.

Immediate ORIF of Gustilo type I and type II open diaphyseal forearm fractures is generally appropriate, provided that thorough debridement is performed. ^[41] Duncan et al reported 90% acceptable results in persons with Gustilo type I, type II, or type IIIA open diaphyseal fractures treated in this manner; however, their results with IIIB and IIIC injuries were poor. ^{[42, 43]}  Several studies have suggested that in children with Gustilo type I open forearm fractures, nonoperative management may be appropriate. ^[44]

Operative details

Internal fixation of the fractures is best done as soon after the injury as is practical, preferably before the onset of swelling. With delayed fracture presentation, blisters secondary to swelling can develop. Ruptured fracture blisters or abrasions older than 6-8 hours may be a contraindication for surgery. At least 7-10 days may be required for abraded skin and fracture blisters to heal and for swelling to subside.

Ulnar approach

An interneural approach between the extensor carpi ulnaris (ECU) and the flexor carpi ulnaris (FCU) is followed. The plate can be used on either the posterior or the anterior surface, though the posterior surface is preferred because it is the tension side of the ulna. Care should be taken to avoid damage to the dorsal sensory branch of the ulnar nerve in the distal part of the incision.

Palmar approach of Henry

The palmar approach of Henry is the most common approach for fixation of the shaft of the radius. It uses the interneural interval between the brachioradialis (radial nerve) and the pronator teres (or the flexor carpi radialis [FCR] distally, innervated by the median nerve). For deep dissection, the arterial branches of the radial artery supplying the brachioradialis are carefully ligated. Rotation of the forearm enhances the view during this approach.

Dorsolateral approach

Access to the radial shaft runs in the septum between the extensor carpi radialis brevis (ECRB) and extensor digitorum muscles. It can be useful for fractures of the proximal and middle thirds of the radius and to address injuries to the proximal radioulnar joint (PRUJ). The dorsolateral approach (also called the Thompson approach) potentially involves less soft-tissue stripping than the palmar approach, and patients may experience a more rapid return of wrist and hand function.

The two nerves vulnerable to injury with this approach are the following:

• The superficial radial nerve in the distal part of the incision along the brachioradialis crossing the abductor pollicis longus (APL) in the subcutaneous layer
• The posterior interosseous nerve running through the supinator in the proximal exposure

Reduction techniques

Periosteal stripping should be limited to a minimum, and circumferential stripping is to be strictly avoided. Plates of 3.5 mm have been proved to be the ideal size for the forearm bones. The purpose of the plate is to neutralize the torsional forces, and purchase should be obtained at no fewer than six cortices in each main fragment in order to achieve this objective. Interfragmentary lag screws, inserted either independently or through a plate hole, should be used to strengthen the fixation if the fracture configuration allows it.

Closure

It is of the utmost importance to close only the subcutaneous tissue and skin. If the deep fascia is sutured tightly, edema and hemorrhage may cause increased pressure in the forearm compartments, which can lead to ischemic contracture. A suction drain can be used to decrease the hematoma and resultant swelling. The drain is removed in 12-24 hours.

If the rigidity of the fixation is sufficient, limited postoperative cast immobilization is used. A posterior splint can be applied for 1-2 weeks for comfort. Patients are encouraged to perform both active and active-assisted range-of-motion (ROM) exercises of the shoulder and hand.

Elbow ROM and pronation-supination exercises should begin as soon as remission of pain and swelling of the forearm permits after the plaster splint is removed. However, in the case of a noncompliant patient, external immobilization (usually an above-the-elbow cast) is essential, along with supervised physiotherapy until the fracture is deemed united on the basis of radiographic findings.

Nonunion and malunion

Nonunion of fractures of the shafts of the radius and ulna is relatively uncommon. Anderson's series of forearm fractures treated with compression plates included nine nonunions (2.7%) and four delayed unions (1.2%) in 330 fractures. ^[13] Almost all of the nonunions and delayed unions appeared to have been caused by infection or errors in surgical technique (see the images below). Accurate ORIF prevents most of these complications. ^[45]  A retrospective study by Vasara et al cited a nonunion rate of 5% in adults with diaphyseal forearm fractures treated by means of ORIF with plates. ^[46]

Infection

Stern et al reported a 3.1% rate of osteomyelitis in forearm fractures; both instances occurred in patients with massive crush injuries (see the image below). ^[47] With good technique and a contemporary operating environment, the rate is currently much lower.

Superficial infections respond well to appropriate antibiotics. The general principles of surgical debridement and copious irrigation are key in treating deep infections. The internal fixation can be left in situ while the infection is being treated, and most fractures proceed to union. The metal can be removed after union of the fracture.

Aggressive treatment is required for late infections, when fixation has been lost and nonunion has developed. Metal should be removed along with any nonviable bone. The wound can be left open for dressing changes, or an irrigation-suction system can be instituted.

If an intercalary defect results, it can be spanned with a long plate and bone grafting when the wound is healthy and after a period of dressing changes. Serial examinations of the wound are required to determine the appropriate timing for the bone-grafting procedure. If the intercalary defect is large (>6 cm), a vascularized fibular bone graft should be considered to bridge the defect (see the image below).

Compartment syndrome

Compartment syndromes (see the image below) can occur in the forearm either after trauma or after surgery. Eaton et al reported 19 patients with Volkmann ischemia, resulting from a volar compartment syndrome of the forearm. ^[48] Auld et al, in a study of patient with both-bone forearm fractures, found that the Orthopaedic Trauma Association (OTA)/Arbeitsgemeinschaft für Osteosynthese (AO) classification was a significant predictor of compartment syndrome risk, with group C fractures representing the highest risk. ^[49]

An important early sign is pain out of proportion to the injury and pain upon passive extension of the fingers. The presence of the radial pulse is not a reliable diagnostic indicator; the radial pulse was absent in only five of their 19 patients. It is important to keep in mind that the presence of a palpable radial pulse does not rule out the presence of a compartment syndrome.

In conscious patients, the diagnosis of compartment syndrome is made on the basis of clinical findings. Compartment pressures can be measured to confirm the diagnosis of compartment syndrome, provided that treatment is not delayed. Measurement is especially valuable when making the diagnosis of compartment syndrome in unconscious or obtunded patients.

Surgical treatment should be performed early and should include fasciotomy from the elbow to the wrist, including division of the lacertus fibrosis proximally and the transverse carpal ligament distally (see the image below). Delayed closure of the wound is performed later. A residual defect may require split-thickness skin grafting.

As a potential alternative to the traditional long approaches to fasciotomy for acute compartment syndrome caused by fracture, Hu et al described mini approaches fasciotomy combined with vacuum sealing drainage (VSD) in 126 children with extremity fractures (upper extremity, n = 74; lower extremity, n = 52); this method was found to be effective and safe. ^[50]

Closed compartment syndromes that follow operations in the forearm are usually due to inadequate hemostasis or closure of the deep fascia. They can usually be avoided by releasing the tourniquet before wound closure to make sure hemostasis is adequate and by closing only the subcutaneous tissue and skin.

Implant removal and refractures after implant removal

Removal of implants is not mandatory and is rarely indicated in an asymptomatic patient because of the risk of complications, including neurovascular injury and refracture. If implant removal is indicated, it should not be performed for at least 18 months to 2 years after internal fixation—and even then, only after careful consideration by an experienced surgeon.

Removal of forearm fracture plates after healing is not a benign procedure. The rate of refracture ranges from 3.5% to 25%. Evidence indicates that the use of the 3.5-mm plate has considerably reduced the rate of refracture. Comminuted fractures, open fractures, bone defects, technical failure (excessive stripping, inadequate compression), and early plate removal within 1 year after internal fixation increase the risk of refracture. ^[51]

Once a plate has been removed, the forearm should be protected by a splint for 6 weeks. It should then be protected from severe stress and torsion for 6 months. Patients undergoing elective removal of implants should be warned of the potential for refracture even later than 6 months. Mih et al reported an 11% refracture rate in 62 patients, with a mean time to refracture of 6 months. ^[52]

In pediatric fracture patients, removal of titanium elastic nails after elastic stable intramedullary nailing (ESIN) appears to be a safe procedure with a low complication rate. ^[53]

Synostosis

Bauer et al reported that the highest risk of synostosis is associated with internal fixation of fractures involving the proximal third of both the radius and the ulna. ^[54] Extensive soft-tissue dissection during exposure, the development of a radioulnar hematoma, the risk of interosseous damage, and occasional malpositioning of the dorsal plate if the Boyd approach is used also contribute to an enhanced risk of postosteosynthetic synostosis (see the image below).

In cases where both bones are fractured, separate surgical approaches for the radius and the ulna have been shown to minimize the risk of radioulnar synostosis.

Follow-up radiographs are taken regularly during the postoperative phase until progressive healing is documented. Determining when a rigidly plated fracture of the forearm has healed on the basis of radiographic findings is difficult, partly because very little external callus results when fractures are stabilized in a rigid manner as is the case for plate-and-screw fixation of radius and ulna fractures. Strenuous activity must be prohibited until bone trabeculae cross the fracture.