You are in: eMedicine Specialties > Orthopedic Surgery > HAND AND UPPER EXTREMITY Middle Third Forearm FracturesArticle Last Updated: Dec 4, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 12
  Author: Janos P Ertl, MD, Clinical Assistant Professor, Department of Orthopedic Surgery, University of California at Davis; Director of Amputee Clinic, Chief of Orthopedic Trauma, Kaiser Hospital Janos P Ertl is a member of the following medical societies: American Academy of Orthopaedic Surgeons, Hungarian Medical Association of America, Orthopaedic Trauma Association, and Sierra Sacramento Valley Medical Society Editors: Peter M Murray, MD, Associate Professor of Orthopedic Surgery, Mayo Clinic College of Medicine; Director of Education, Mayo Foundation for Medical Education and Research, Jacksonville; Consultant, Department of Orthopedic Surgery, Mayo Clinic, Jacksonville; Consulting Staff, Nemours Children's Clinic and Wolfson's Children's Hospital; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Robert J Nowinski, DO, Clinical Assistant Professor of Orthopaedic Surgery, Ohio University College of Osteopathic Medicine; Private Practice, Orthopedic Specialists and Sports Medicine, Newark, Ohio; Dinesh Patel, MD, FACS, Associate Clinical Professor of Orthopedic Surgery, Harvard Medical School; Chief of Arthroscopic Surgery, Department of Orthopedic Surgery, Massachusetts General Hospital; Harris Gellman, MD, Consulting Surgeon, Broward Hand Center, Voluntary Clinical Professor of Orthopedic Surgery and Plastic Surgery, Departments of Orthopedic Surgery and Surgery, University of Miami School of Medicine Author and Editor Disclosure Synonyms and related keywords: both-bone forearm fracture, BBFF, forearm fracture, middle third radius and ulna fracture, middle third diaphyseal forearm fracture, broken arm, broken forearm, Henry approach, Thompson approach INTRODUCTIONSection 2 of 12
  For descriptive purposes, as well as for operative considerations, forearm fractures are classified by location, being categorized as proximal, middle, or distal third fractures. The middle third of the radius stretches from the radial bow to the beginning of diaphyseal straightening. The ulna is relatively straight and can be divided using longitudinal dimensions alone. (See also the eMedicine articles Forearm Fractures, Distal-Third Forearm Fractures, and Fractures, Forearm.) Treatment objectives for both-bone forearm fractures have remained relatively constant, with early extremity range of motion. To understand the management of forearm fractures, the idea of the forearm axis was created, combining the function and anatomy of the wrist, forearm, and elbow. The coordinated, independent function of the wrist, forearm, and elbow is necessary to place and orient the hand in space. Injury to any of these components can result in a significant deficit. The 3 basic stabilizers of the forearm are as follows:
For a review of Galeazzi and Monteggia forearm fractures, see the eMedicine articles Galeazzi Fracture and Monteggia Fracture). For excellent patient education resources, visit eMedicine's Breaks, Fractures, and Dislocations Center. Also, see eMedicine's patient education article Broken Arm. ProblemUnlike fractures in infants and children, fractures of the adult forearm are unstable. Nonunions and malunions of both-bone forearm fractures are functionally and cosmetically limiting, with midshaft radius or ulna angulation substantially impeding forearm rotation. FrequencyAccording to the AO (Arbeitsgemeinschaft für Osteosynthesefragen [Association for Osteosynthesis]) documentation center, forearm fractures accounted for 10-14% of all fractures between 1980 and 1996. EtiologyMiddle third, or diaphyseal, forearm fractures commonly result from a direct blow or a fall from a height. Other causes include gunshot wounds, motor vehicle accidents, and pathologic bone fractures. ClinicalPatients with middle third forearm fractures present following an identifiable traumatic event. Multiple injuries to the musculoskeletal and associated systems frequently occur in conjunction with forearm fractures. In patients who sustain multiple traumas, any life-threatening injuries take priority in treatment and stabilization. Forearm fracture management objectives remain the same whether they are isolated or occur in the polytrauma setting, with early stabilization recommended. Physical examination of the patient with a forearm fracture includes a close inspection of the skin to rule out puncture wounds and abrasions. Additional soft-tissue evaluation is performed to rule out compartment syndrome, which is associated with low- and high-velocity injuries. A careful neurologic and vascular examination is carried out to identify any deficits that were caused by the injury. Loss of posterior interosseous nerve (PIN) function in Monteggia fracture patterns has been well described. The PIN innervates the extensor musculature below the elbow, which functions to extend the digits. Anterior interosseous nerve (AIN) palsy also may be present and is often overlooked because this finding has no sensory component. A division of the median nerve, the AIN arises from the posterior aspect of the median nerve, 5 cm distal to the medial humeral epicondyle, and passes between the heads of the pronator teres. The AIN is primarily a motor nerve; injury to it can cause paralysis of the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP-I) to the index finger, causing loss of pinch between the thumb and index finger. The AIN terminates in sensory fibers to the distal radioulnar, radiocarpal, intercarpal, and carpometacarpal joints. Palsy has been associated with internal fixation of forearm fractures, as well as with tight external dressings.1 INDICATIONSSection 3 of 12
Nonoperative treatment of middle third forearm fractures is reserved for isolated ulnar shaft fractures, better known as nightstick fractures. (See also Interventions for Isolated Diaphyseal Fractures of the Ulna in Adults, on Medscape.) Radiographs of the wrist and elbow must be obtained in isolated radius and ulna fractures to rule out Monteggia and Galeazzi injury patterns. These injuries are best treated surgically in the adult patient. Both-bone middle third forearm fractures in adults are unstable injuries that lead to shortening and angulation. The goal of treatment is to achieve a stable anatomic reduction. The literature recommends open reduction and internal fixation (ORIF) for displaced fractures of the middle third of the forearm in adults to restore early forearm motion. Precise anatomic reduction is necessary to re-establish the radial bow and proper interosseous space and therefore to maintain normal motion.2 Even small amounts of malalignment may lead to a functional disability at the wrist and/or elbow. All open forearm fractures require appropriate irrigation and debridement with subsequent surgical stabilization. Open fractures of grades I, II, IIIa, and (occasionally) IIIb are treated according to the same principles of closed fractures in association with meticulous debridement of the soft tissues. Results of the debridement and immediate internal fixation of open fractures are comparable to those of the surgical treatment of closed fractures.3 Open wound management is recommended, with repeated debridement as necessary. Primary closure of the extension incisions of the traumatic wound may be performed, and delayed wound closure may be performed once the soft tissues have declared themselves. Forearm fractures accompanied by soft-tissue loss that results in an inability to cover plates may require other forms of stabilization. Temporary stabilization with an external fixator may be achieved while planning soft-tissue coverage with rotational or free flaps in conjunction with delayed (secondary) internal fixation (plating). Most forearm fractures in children can be stabilized and treated by means of closed reduction and cast immobilization. Occasionally, some pediatric forearm fractures can be unstable, leading to displacement, radioulnar angulation, rotational malalignment, and encroachment of the interosseous space. Angulation of greater than 10º results in loss of rotation in children older than 10 years and should be avoided. RELEVANT ANATOMYSection 4 of 12
The ulna is the stable unit about which the radius rotates. Force transmission is initiated at the wrist (the distal radioulnar joint) level and is translated longitudinally between the radius, ulna, and interosseous membrane, through the forearm axis, and to the elbow. An applied compressive load travels along the proximal radius, transferring tension forces to the interosseous membrane, which transfers a compressive load to the proximal ulna.5 This mechanism accounts for the inequality in the contact forces between the radius and ulna at the wrist and elbow. Fracture and/or dislocation of the forearm lead to disruption of this longitudinal relationship and affects wrist, forearm, and elbow function. CONTRAINDICATIONSSection 5 of 12
The forearm joint must be reconstructed anatomically to regain and re-establish function. Every effort should be made to maintain normal anatomic relationships. Contraindications to surgical treatment include life-threatening trauma conditions, which may delay or preclude surgical intervention. Rarely are patients so medically unstable that both-bone forearm fractures cannot be promptly treated by surgery. WORKUPSection 6 of 12
Imaging Studies
TREATMENTSection 7 of 12
Surgical TherapyEarly surgical intervention (within the first 6-8 hours) is optimal to avoid radioulnar synostosis. Fixation options include plate fixation, external fixation, and IM nailing.6 Plate fixation with anatomic reduction is thought to produce the best functional results in closed or open fractures. External fixation is primarily indicated for open grade IIIb and IIIc fractures with severe soft-tissue injury. Additional secondary procedures are often necessary, and when used for definitive fracture treatment, external fixation results in a 67% adequate functional result. The role of IM nailing is not clearly defined; however, several implant options are currently available.7 Restoration of the radial bow is the goal and is best achieved with stable internal fixation techniques using 3.5-mm compression plates. The ulna is fairly straight and may be treated with relative stability techniques. Surgical approachesDisplaced fractures of the middle forearm in the adult are best treated with open surgical reduction and internal fixation. The surgeon should be familiar with several surgical approaches to the forearm because of the wide variety of fracture patterns that can occur. The soft-tissue injury of closed and open fractures may dictate the exposure utilized, with the length of the incision being determined by the fracture. The diaphysis of the middle third of the radius may be exposed using the Henry approach or the Thompson approach. The Henry approach The Henry approach, also known as the anterior approach or the volar approach, is extensile and may be extended from the wrist to the elbow. This approach exposes the flat tension surface of the radius, which is ideal for plate application. In addition, fasciotomies for compartment syndromes are best implemented through this approach. The incision begins 1 cm lateral to the biceps insertion and extends distally to the radial styloid. The fascia is split, and the brachioradialis and the extensor wad (the extensor carpi radialis brevis and longus) are radially retracted. The radial artery, which must be protected, is identified as it extends along the flexor digitorum superficialis. The radial sensory nerve may be found on the undersurface of the brachioradialis. The median nerve can be found between the palmaris longus and the flexor carpi radialis. The flexors and the median nerve can be retracted toward the ulna, and the middle third of the radius is exposed. The Thompson approach An alternative means of exposing the radius may be performed using a Thompson, or dorsolateral, approach. This approach is best suited for exposure of the proximal and middle thirds of the radius; however, it is not an extensile approach. The incision begins at the lateral epicondyle and extends along the extensor wad over the dorsolateral border of the radius. The fascia is incised, and the interval is developed between the mobile wad and the extensor digitorum, exposing the supinator muscle. In the proximal third of the exposure, the PIN passes through the supinator muscle at right angles to the muscle fibers. The forearm is supinated, protecting the PIN, and the insertion of the supinator is elevated, exposing the subcutaneous tension surface of the radius. The ulna approach The ulna is exposed along the subcutaneous border between the flexor and extensor carpi ulnaris. Depending on the fracture pattern, the extensor or flexor muscle is elevated from the ulna in preparation for plating. The dorsal cutaneous branch of the ulnar nerve is found 6-8 cm proximal to the ulnar styloid and must be identified and protected. Preoperative DetailsA preoperative plan should be determined. The fracture is outlined on the radiograph, cut out, reduced or realigned, and drawn on another sheet, with the definitive fixation placed in the best position. Depending on the fracture type and the soft-tissue injury, prepare the operating room staff for the planned procedure. Be prepared to harvest iliac crest bone graft if necessary. Primary bone grafting is controversial but is recommended when comminution is more than 33% of the bone circumference. Have available a 3.5-mm fracture reduction set, a radiolucent hand table, a C-arm, and allograft bone graft, if necessary. The plate that has gained widespread acceptance is the 3.5-mm dynamic compression plate. The development of indirect reduction techniques and a more biologic approach to plate fixation of forearm fractures has been enhanced by newer plate designs, such as the limited contact dynamic compression plate. In most cases, a plate of adequate length, applied with appropriate technique, is of sufficient strength to support functional load while the fracture heals. At least 8 cortices above and below the fracture are usually required, except in the case of a pure transverse fracture, which is effectively held with 6 cortices on each side. In cases of comminution, 10- or 12-hole plates are typically required. An external fixator may be necessary in high-energy and high-grade open fractures. The choice of fixator is determined by the surgeon's experience and comfort. The operative consent should be written in such a way that it covers all possibilities and fixation options. Risks of the operative procedure must be thoroughly explained and understood by the patient and, if present, his/her family. Intraoperative DetailsMost middle third forearm fractures are easily approached with the patient in the supine position and the arm extended on an arm board or hand table. The surgical events are as follows:
Postoperative DetailsThe patient's neurovascular status and forearm swelling should be monitored for possible compartment problems. The neurovascular status is monitored in the operating room and in the postanesthesia recovery room. Beginning on postoperative day 1, a physical therapist is consulted to assist in digital range of motion. To avoid hematoma formation, progressive wrist and elbow motion are delayed for 3-5 days. If any question exists regarding the stability of internal fixation or patient reliability, external functional bracing should be instituted to provide support for the forearm skeleton—and still permit functional use of the extremity—through a careful interosseous mold created by the splint. Follow-upForearm rotation is initiated as the patient's comfort allows, often between the first and second week postoperatively. The patient is monitored as an outpatient at 2 weeks, 6 weeks, 12 weeks, and 4-6 months postoperatively with anteroposterior and lateral radiography. Activity modification should be limited to activities of daily living during fracture healing, which should be completed by 3-4 months postoperatively. Once the fracture is healed (as demonstrated radiographically), the patient may progressively return to sports and resume a normal lifestyle. COMPLICATIONSSection 8 of 12
Restoration of the radial bow is important to the functional outcome. Failure to restore the radial bow to within 5% of the contralateral side results in a 20% loss of forearm rotation, as well as loss of grip strength. Complications of forearm fractures include the following:
The incidence of refracture of the forearm after plate removal is unknown but has been reported to be 4-25%. Factors that contribute to refracture include premature plate removal at less than 1 year, delayed union, nonunion, the use of 4.5-mm dynamic compression plates, and poor surgical technique. Plate removal can be considered when cortical remodeling under the plate is radiographically present, typically after 18 months. Forearm protection after plate removal is recommended for 6 weeks, and a return to sports or other activities is delayed for 3-4 months. Forearm plate removal is not without risk, including infection and nerve injury.9 The incidence of these complications is 10-20%, and plate removal is not routinely recommended. Malunion and nonunion of forearm fractures have been occurring less commonly since the use of compression plating became a standard treatment. With proper technique and a compliant patient, the nonunion rate is approximately 2%. Infection after operative treatment of forearm fractures is uncommon. The incidence of infection in open fractures has been reported to be 0-3%. Acute infections require standard treatment with irrigation and debridement, and the hardware should not be removed if the fixation is stable. When the hardware is stable, it maintains length, rotation, and alignment and assists in wound care. In late infections, treatment is similar, and plate removal may be performed if the fracture is healed. During the initial injury that causes a forearm fracture, neurovascular injury also may occur. Vascular injuries usually involve 1 major artery and do not lead to loss of hand viability. Nerve injuries are usually neuropraxias, and recovery occurs spontaneously. In complete nerve transection, exploration and primary repair, delayed primary repair, or nerve grafting is performed when appropriate. The results of nerve repair are variable depending on the nature of the wound and the extent of the nerve injury. Iatrogenic nerve injury most often involves a branch of the radial nerve. The PIN can be injured during the dorsal approach, and the radial sensory nerve can be injured during the volar approach. Compartment syndrome usually occurs in high-energy injuries but may occur in low-energy injuries as well. A high index of suspicion is necessary, and expedient compartment releases are performed (see the eMedicine article Compartment Syndrome, Upper Extremity). A 0-11% (most commonly, 3%) incidence of radioulnar synostosis has been reported. Risk factors include fracture of the radius and ulna at the same level, head injury, infection, high-energy trauma, the single-incision surgical approach, bone graft within the interosseous space, screws that are too long, and a 2-week–delayed operation. Bone scanning should be used to monitor the maturity of the bony synostosis. Once the activity has decreased, the synostosis can be resected within 1-2 years postfracture. OUTCOME AND PROGNOSISSection 9 of 12
Since the introduction of compression plating, the goal of forearm fracture treatment has been fracture union and the return of normal function. In 1975, Anderson and colleagues reported their experience with 4.5-mm compression plating of forearm fractures and noted a 97.9% rate of union for the radius and a 96.3% rate of union for the ulna.10 Time to fracture union averaged 7.4 weeks and 7.3 weeks for radial and ulnar fractures, respectively. Additionally, the authors reported a 2.9% infection and nonunion rate. In this report, they developed a functional outcome evaluation scale, as follows:
Using this scale, the authors recorded a combined 85% rate of excellent and satisfactory results for the treatment of 330 acute fractures in 244 patients. In 1989, Chapman and colleagues reported their results from the treatment of 129 diaphyseal fractures of the radius and/or ulna using standard 3.5-mm compression plates.11 They recorded a fracture union rate of 98%, an infection rate of 2.3%, and a 92% rate of excellent or satisfactory results using the Anderson forearm evaluation scale. Similar results have been reported by a number of other authors. Complications in most series were thought to be associated with errors in judgment, with technique, and with a lack of attention to detail. Immediate ORIF is recommended for all open, both-bone middle third forearm fractures. Results have reportedly been excellent or good in 85% of fractures, with an infection rate of 4% and a nonunion rate of 7%. FUTURE AND CONTROVERSIESSection 10 of 12
A minimally invasive approach, IM stabilization through nailing is an attractive alternative to formal ORIF, but indications for it are not yet clearly defined. IM fixation may be performed by either open or closed reduction in unstable transverse fractures. IM devices provide an internal splint, which is able to control bone length and alignment. With newer interlocking nails, rotational alignment can be controlled and maintained. The theoretical advantages of providing longitudinal and angular stability through a minimally invasive approach are less need for soft-tissue dissection and abundant callus formation. MULTIMEDIASection 11 of 12
REFERENCESSection 12 of 12
Middle Third Forearm Fractures excerpt Article Last Updated: Dec 4, 2007 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
