Operative management of chest wall injuries is a controversial topic. This was highlighted by a recent survey of 238 members of the Eastern Association for the Surgery of Trauma, ninety-seven members of the Orthopaedic Trauma Association, and seventy thoracic surgeons1. The majority of the respondents (82% of the general surgeons, 66% of the orthopaedic surgeons, and 71% of the thoracic surgeons) responded that operative repair of rib fractures was indicated in selected patients. Fewer (17% of the general surgeons, 32% of the orthopaedic surgeons, and 23% of the thoracic surgeons) responded that operative repair of rib fractures was rarely or never indicated. Only 21% of the trauma surgeons, 16% of the orthopaedic surgeons, and 52% of the thoracic surgeons indicated they had ever performed or assisted in open reduction and internal fixation (ORIF) of rib fractures. Twenty-two percent (eighty-nine) of all 405 respondents indicated that they were familiar with a randomized trial of surgical repair of flail chest1.
In 2004, over 300,000 people were treated for rib fractures in the U.S.2, with 102,000 patients being admitted to U.S. hospitals3. Because the majority of patients with rib fractures are not admitted to the hospital4, the true incidence may be higher than estimated. Fractures of consecutive ribs have been found to be independent markers of injury severity, resulting in increased morbidity and mortality5-7. An estimated 25% of annual traumatic deaths result from chest trauma. Rib fractures have been detected in up to 39% of patients (548 of 1417) who have sustained blunt chest trauma and up to 10% of trauma admissions overall (711 of 7147). Flail chest is present in up to 6% of patients (eighty-two of 1417) who have sustained blunt chest trauma4,8-15. These injuries are potentially fatal, with in-hospital mortality rates of up to 12% (eighty-four of 711) for patients with multiple rib fractures and up to 33% (thirty of ninety-two) for patients with a flail chest8,16-18. Nonoperative management, consisting of pulmonary toilet, pain control, and selective ventilatory support, is the standard treatment for these injuries at most institutions. Operative intervention is controversial19, although several reports indicate that patients who underwent ORIF of flail chest injuries or multiple rib fractures required a shorter duration of ventilator support, were less likely to develop infections and septicemia, and were less likely to require tracheostomy than patients managed nonoperatively20-22.
The orthopaedic surgeon is often consulted about concomitant fractures and is often the specialist who follows the patient for the longest period of time. Thus, it is paramount that orthopaedic surgeons be aware of the short and long-term sequelae of these chest wall injuries as well as the potential benefit of ORIF of fractured ribs in the setting of massive chest wall trauma.
Proposed Benefits of Operative Fixation
Reported short-term benefits of ORIF of rib fractures and flail chest include accelerated restoration of pulmonary function20,28,42,44,45,49,50, reduced morbidity associated with prolonged mechanical ventilation6,21,28,29,42,44,49,51, and shortened stays in the intensive-care unit and the hospital20,42,52. These advantages typically lead to a shorter recovery time and a faster return to work. Early restoration of chest wall integrity and respiratory pump function after ORIF may prove to be cost effective through the prevention of prolonged mechanical ventilation and restriction-related work capacity. Reported long-term benefits of ORIF include a decreased likelihood of clinically relevant long-term pain, respiratory dysfunction, and skeletal deformity28,50,53. There is also a theoretical advantage of improved lung functional reserve following ORIF secondary to restoration of greater lung volumes.
Although surgery is rarely utilized, a review of the literature indicates that there are occasional situations where operative management of rib fractures should be considered. All indications are currently considered relative; there are no absolute indications based on available studies. Treatment must be individualized on the basis of the patient's fracture pattern, overall medical condition, and functional status (Table I)19.
Flail Chest
Flail chest is variably defined in the literature. The most commonly cited definition is unilateral fractures of four consecutive ribs, with each rib fractured in two or more places. Clinically, flail chest is diagnosed when an incompetent segment of chest wall is large enough to allow paradoxical motion of the chest wall with respiration25,29,48 (Figs. 2-A, 2-B, and 2-C). A sternal flail chest occurs when the sternum becomes dissociated from the hemithoraces as a result of bilateral, multiple, anterior cartilage or rib fractures. Two recent randomized trials indicated that selected patients with flail chest may benefit from ORIF in both the short and the long term42,54. Several nonrandomized, cohort-comparison trials have also generally confirmed these findings, with the caveat that flail chest repair is not advisable for patients with substantial pulmonary contusions20,22,45. In the Eastern Association for the Surgery of Trauma (EAST) Practice Management Guideline for "Pulmonary Contusion—Flail Chest," ORIF for severe unilateral flail chest or for patients requiring mechanical ventilation when thoracotomy is otherwise indicated was considered to be a Level-III recommendation55. Level-III recommendations are defined by EAST as being supported by Class-III studies (retrospectively collected data). EAST states that this type of recommendation is useful for educational purposes and in guiding future clinical research only. They cited the low numbers of patients randomized, the strict exclusion criteria in the study by Tanaka et al.42, and the absence of trials comparing operative repair with "modern" nonoperative treatments as reasons for the Level-III designation.
Chest Wall Deformity or Defect
Chest wall defects or deformities can result from severely displaced rib fractures with or without soft-tissue loss. Paradoxical motion may be noted if a flail segment is present. Many patients, especially those who are young and have adequate pulmonary reserve, do not require endotracheal intubation. Minimal to moderate-size tissue defects can be caused by penetrating missiles, shotgun injury, or impalement by surrounding objects. In these cases, repair of both rib fractures and soft tissues may be indicated to restore chest wall competency (Fig. 3).
Acute Pain and Disability
It has been hypothesized that certain patients experiencing persistent, unrelenting pain with breathing, coughing, or mobilization may benefit from ORIF30,47,49. This suggestion has not been confirmed by cohort-comparison or randomized trials. It has been suggested that, if their pain were alleviated by acute ORIF, patients could possibly return to work and their usual activities sooner56.
Nonunion
A small percentage of rib fractures do not heal and may develop into a symptomatic nonunion. Fibrous tissue and pseudarthrosis are characteristic histological findings. Patients with nonunion have reported pain, tenderness, a sensation of "jabbing" into the lung with deep respiration, clicking with motion of the ipsilateral shoulder girdle47,48, or pain with sneezing and other bodily motions involving a Valsalva maneuver. In the past, rib nonunions have been treated with rib resection or cancellous bone-grafting19, although resection does not always guarantee lasting relief of pain. More recently, ORIF has been employed to treat rib nonunion30,37,47,48,57-59.
Thoracotomy for Other Indications
A patient who undergoes a thoracotomy for another indication such as an open pneumothorax, pulmonary laceration, retained hemothorax, or diaphragmatic laceration may be a candidate for ORIF of rib fractures. Thoracotomy for nontraumatic indications such as tumor resection also may result in rib fractures that can be surgically repaired. Stabilizing the fractured ribs prior to closure after completion of the primary procedure may increase patient comfort and improve pulmonary care.
Open Fractures
Although, to our knowledge, no published study has addressed the treatment of open rib fractures, it is reasonable to apply standard principles of open fracture management to these injuries. The goals of treatment of open rib fractures are to prevent infection, allow the fracture to heal, and restore function. We believe that the standard principles of imparting stability to open extremity fractures after irrigation and debridement may be equally relevant to the treatment of chest wall injuries in order to decrease pain and the risk of infection and nonunion.
Preoperative Planning
The geometry and character of human ribs are unique among the bones of the body and contribute to the challenge of rib fracture fixation. Human rib thickness ranges from 8 to 12 mm with a relatively thin (1 to 2-mm) cortex surrounding soft marrow60. Individual ribs do not have good tolerance to stress and do not provide good cortical screw purchase. Rib fractures may be oblique or even comminuted, further complicating the challenge of obtaining reliable fixation. In addition, the intercostal nerve lies in a groove under the inferior surface of the rib, and iatrogenic injury from manipulation of the fractured ribs or placement of orthopaedic implants may lead to post-thoracotomy pain syndrome49,61. Three-dimensional CT reconstructions may be useful to completely define all rib fractures and the extent of their displacement and to help plan the surgical approach37,49,62. If possible, chest tubes are removed from the pleural space at least a day before ORIF to minimize the potential for bacterial contamination. Antibiotics are routinely given perioperatively.
Operative Technique: Our Preference
Mayberry et al.1 found that 33% (seventy-nine) of 238 trauma surgeons, 48% (forty-seven) of ninety-seven orthopaedic trauma surgeons, and 91% (sixty-four) of seventy thoracic surgeons considered themselves competent to perform the surgery. We recommend that a thoracic surgeon be present to assist with the operative approach if the orthopaedic surgeon is unfamiliar or inexperienced with thoracic approaches.
The patient is placed in the lateral decubitus position. A standard thoracotomy incision is made overlying the fractured ribs. Dissection is carried sharply through skin, subcutaneous tissues, and fascia. The serratus anterior muscle is retracted anteriorly and the latissimus dorsi muscle is retracted posteriorly, to the extent necessary as determined by how anterior or posterior the incision is placed. Muscle-sparing techniques, such as division of the latissimus dorsi muscle in line with its fibers, can provide adequate exposure of up to three rib fractures through an incision 10 to 15 cm in length. Alternatively, instead of making one larger incision, the surgeon can make multiple smaller incisions that avoid muscle division. The intercostal muscles are incised over the superior border of the rib at the desired level. By entering the pleural cavity, this approach provides excellent visualization during ORIF. The ability to reduce the rib from inside the thoracic cavity via manipulation is important, given that the fractured ribs displace toward the midline. Throughout the procedure, the lung is observed and protected.
Single-lung ventilation is useful to improve exposure and avoid injury to the lung parenchyma on the intrathoracic side of the dissection. However, the presence of a pulmonary contusion may limit tolerance of single-lung ventilation. In addition to the lung affected by contusion, there can be impairment of the noncontused lung due to the systemic inflammatory response syndrome initiated by the trauma in some patients. If there is no evidence of contralateral lung injury, single-lung ventilation is likely to be successful52,63.
Early ORIF reduces the extent of thoracic wall dissection necessary for mobilization and excision of callus. The ends of the fractured ribs are cleared of their soft-tissue attachments for a distance of 1 to 2 mm with use of an elevator. Curets and pituitary rongeurs are used to carefully clean any debris from the fracture site. Care must be taken to avoid violating the intercostal neurovascular bundles located on the inferior aspect of the ribs. When there is a nonunion, the medullary canal is reestablished with an appropriately sized drill bit in oscillate mode to avoid cortical penetration. The fracture ends are mobilized and reduced with use of a combination of bone reduction clamps and dental picks. Unicortical drill holes are useful to create purchase points for reduction tools during mobilization, reduction, and fixation. Displaced rib fractures tend to shorten and overlap; thus, gaining compression is not generally an issue once reduction is obtained.
Plates may be applied directly over the periosteum of the rib. The fractured ribs adjacent to the thoracotomy site are typically plated first. The senior author (P.A.C.) chooses a plate of sufficient length to allow at least six cortices of fixation on both sides of the fracture. As is the case for long-bone fractures, osteoporotic bone may require longer plates or locking constructs to help prevent fixation failure. Given that the fracture site will experience immediate continuous motion with respiration, we recommend the use of locking plates. This fixation option allows use of shorter plates and less surgical exposure. The choice of implants as well as relative screw configurations depend on many factors such as the bone quality and whether the surgeon desires secondary or primary healing. If precontoured plates are not available, the senior author recommends using a template to contour a 2.7-mm locking reconstruction plate or 3.0-mm mandibular locking plate of appropriate length. The fractured ends of the ribs should be placed under compression before screws are placed, with bone graft possibly added in cases of nonunion. The ribs on both sides of the thoracotomy are sequentially approximated. It is unnecessary to plate all of the fractured ribs in a large thoracic segment, but enough of them must be plated to provide internal splinting to the remaining ribs and to help restore thoracic contour (Figs. 2-A, 2-B, and 2-C). Ribs anterior to the scapula are difficult to access safely and generally should be left unfixed given the added muscular protection and stabilization from the periscapular musculature. Additionally, deformity of the upper ribs results in less lung-volume loss. At the conclusion of fixation, the pleural cavity can be filled with saline solution and the lung can be reinflated to check for air leaks. If a leak exists, a chest tube should be placed. Wound drains are used at the discretion of the operating surgeon, on the basis of an assessment of the wound. A layered muscular closure with absorbable suture is then executed. The chest tube is left in place until the lung is fully reinflated, no evidence of pneumothorax is present on radiographs of the chest, and the drainage and air leak have ceased64.
Fixation Options
Fixation must be able to tolerate up to 25,000 breathing cycles per day as well as coughing. Both rigid and nonrigid systems have been developed. Potential disadvantages of both rigid and nonrigid internal fixation systems include interference with CT and MRI (magnetic resonance imaging) studies, stress-shielding, palpable implants, and the potential need for another operation for implant removal due to pain or loosening of implants29,56,65.
Metal Plates
The use of metal plates is the standard choice for operative fixation of rib fractures29,31,37,45,51,64-66. Generic 3.5-mm and 2.7-mm reconstruction plates, one-third tubular plates, dynamic compression plates, and low-contact dynamic compression plates contained in standard small and mini-fragment implant sets have been utilized, as have plates designed for maxillofacial surgery29,43,47,59,64,65,67. These maxillofacial plates may be 2.4, 2.7, or 3.0 mm and are made of titanium or stainless steel. Recently, there has been a move toward using locking plates with either bicortical or unicortical screws, especially in patients with osteopenic bone or in whom there is poor screw purchase58,65,68. Generic small and mini-fragment plates have the disadvantage of requiring extensive contouring51,58,59,68. Because of the complex geometry of ribs, intraoperative contouring of plates can be difficult. Furthermore, the use of generic plates has been accompanied by screw loosening and pullout in several reports31,43,45,67.
Recently, investigators have attempted to address these deficiencies. Mohr et al.69 performed a study to establish a biometric foundation to generate specialized, anatomically contoured implants for rib fixation. These implants theoretically should improve maintenance of reduction and stability, decrease the incidence of implant loosening, shorten the operative time, and consequently decrease the risk of infection and nonunion or failure of the implant. Precontoured plates are relatively thin, which minimizes stress-shielding while allowing physiologic motion during respiration. The clinical superiority of precontoured plates has not been proven, making the added cost of these specialized implants difficult to justify at the present time.
Absorbable Plates
Absorbable polymers have been successfully used in the fixation of maxillofacial, tibial, and rib fractures49,60,70-77; in the reconstruction of chest wall deformities78; and in rib reapproximation after thoracotomy for nontraumatic indications79-82. Plates made of absorbable polymer are typically applied with use of absorbable suture material. The plates may be applied on either the interior or the exterior surface of the rib and may be secured by placing the suture either around the rib or through drill holes. These implants retain sufficient rigidity until adequate healing has taken place, resorbing at a rate that slowly transfers mechanical load to bone. This may minimize the problem of stress-shielding, which has been reported with metal implants73,83, and eliminate the potential need for a second operation for implant removal49. Findings in animal models have supported the concept that fractures heal faster, with stronger bone after healing, with use of absorbable plates84,85. In a rabbit model, rib fracture reduction was maintained to a greater degree with polylactide plate fixation of ribs than with nonoperative treatment, resulting in improved bone healing86. Antibiotics could be added to absorbable plates87,88. Although they have not been reported with the treatment of rib fractures, there are concerns about complications, such as foreign-body reactions, swelling, fluid accumulation, and cyst formation, related to bioabsorbable materials utilized in fracture fixation elsewhere in the body74,89-93. For these reasons, the use of bioabsorbable materials for fracture fixation in other locations has been largely abandoned. Absorbable implants are also more costly than standard metal implants.
Intramedullary Fixation
Intramedullary fixation of rib fractures has been used successfully but is technically demanding and carries the risk of implant dislodgment and migration20,53,55,94,95 as well as poor rotational stability65. Recently, anatomically contoured titanium intramedullary struts designed for rib fracture fixation have been introduced and have improved rotational stability. A broad flat design and the addition of a single unicortical locking screw to hold the strut suggest that this implant design may lessen the risk of dislodgment and migration (Figs. 4-A, 4-B, and 4-C).
Judet Struts
The Judet strut is a bendable metal plate that grasps the rib with tongs both superiorly and inferiorly without transfixing screws45,96-100. Fixation of this plate around the inferior margin of the rib can potentially crimp the intercostal neurovascular bundle, causing intercostal nerve injury and subsequent chronic pain. One variation of the strut that has been reported is a self-gripping, elastic band that envelops the rib28.
U-Plates
U-plates are applied in a manner similar to that used to apply the Judet strut, but they do not have the potential for crimping of the intercostal nerve because the plate is placed along the superior border. U-plates can be placed with minimal dissection of the rib in the extrapleural space, with preservation of the periosteum. They are secured by locking screws placed through the midsubstance of the rib with use of a targeting guide60. Locking screws engage the exterior and interior aspects of the plate and do not rely on screw purchase in bone; thus, they may prove useful in patients with osteoporosis. Sales et al. compared the stiffness of U-plates with that of 2.4-mm locking plates in a 5-mm-gap model and found U-plate fixation to be more durable60. It is theorized that the smaller size of the U-plate compared with standard plates may facilitate more minimally invasive rib fracture repair.