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© 2001 The Journal of Bone and Joint Surgery, Inc.
What’s New in Orthopaedic TraumaThe evaluation and treatment of musculoskeletal injuries, including fractures and dislocations, is the foundation of the specialty of orthopaedic surgery. Virtually every subspecialty deals with fractures and their sequelae. There are many areas of consensus and areas of controversy among the various subspecialties with regard to the appropriate management of fractures. Although most surgeons recognize the key role that soft tissues play in fracture-healing, classic teaching has emphasized the need to achieve maximal stability of bone during fracture fixation, often at the expense of the soft tissues. As our understanding of the biology and mechanics of fracture repair and stabilization improves, the interest in less invasive surgical approaches for fracture fixation is accelerating. Indirect reduction techniques have been developed in an attempt to preserve the blood supply to the injured bone, to improve the rate of fracture-healing, to decrease the need for bone-grafting, and to lower the incidence of infection. This article reviews recent advances in fracture care, emphasizing, when possible, the functional outcomes of treatment as determined with the use of limb-specific outcome measures and the physical function components of general health-status instruments. The article is designed to serve as a primary source for update and review for practicing orthopaedic surgeons who wish to stay current in the rapidly evolving field of orthopaedic traumatology. Information presented at the 2000 Annual Meeting of the Orthopaedic Trauma Association and the 2001 Annual Meeting of the American Academy of Orthopaedic Surgeons is reviewed. In addition, issues of The Journal of Bone and Joint Surgery and the Journal of Orthopaedic Trauma from March 2000 through March 2001 have been reviewed, and their contributions to orthopaedic traumatology will be summarized. Selected contributions from Clinical Orthopaedics and Related Research, the Journal of Trauma, and the Journal of the American Academy of Orthopaedic Surgeons are also reviewed. Background Injury is one of the most important public health problems facing the United States today. It is the leading cause of death of Americans between the ages of one and forty-four years. More than 144,000 people die from injury each year: 56,000 die from causes related to violence, and 88,000 die from unintentional injury, such as that from motor-vehicle accidents, fires, and falls. Injury is also the most common cause of short-term and long-term disability. Millions of Americans are injured each year, leaving many of them temporarily disabled and some permanently disabled with severe injuries of the head, spinal cord, and extremities. Because injury so often occurs in young people, it is the leading cause of years lost from work. At an estimated cost of 224 billion -dollars annually, injury is the most costly "disease" in the United States today. Despite the enormous toll that injury exacts, the amount of research funding allotted to studies of trauma is a small fraction of that for cardiovascular disease or cancer. Although molecular biology and genetic engineering hold great promise for unraveling the mysteries of degenerative, inflammatory, metabolic, or neoplastic disorders of the musculoskeletal system, education and prevention remain the cornerstone of treatment of orthopaedic trauma at present. Pelvic and Acetabular Fractures Unstable pelvic fractures with disruption of the sacroiliac joint complex remain a major source of patient morbidity and mortality. Aggressive resuscitation by a multi-discipli-nary team and the use of noninvasive stabilization devices, angiography with embolization, and early fracture stabilization, have been shown to improve patient outcomes. High-quality plain radiographs and thin-section computed tomography scans permit identification of the location, morphologic characteristics, and displacement of fractures. Unstable sacral and sacroiliac fractures and dislocations are present in nearly one-third of all high-energy pelvic ring injuries and are accompanied by a relatively high risk for additional neurovascular injuries. Iliosacral screw placement has become the standard means of internal fixation for fractures and fracture-dislocations of the sacrum and sacroiliac joints. Nevertheless, the complexity and variations in sacral anatomy make the optimum placement of iliosacral screws -technically difficult. Complications of the misplacement of iliosacral screws can be devastating and can include -damage to the iliac and the superior gluteal vessels, the fourth or fifth lumbar or first sacral nerve roots, and the sympathetic chain. Several authors have investigated techniques to improve the insertion of iliosacral screws with use of helical computed tomography scans to clarify the cross-sectional geometry of the sacral ala for the safe insertion of lag screws. Carlson et al.1 described the "vestibule" concept to better define the starting point on the ilium and the safe zone for insertion of iliosacral screws. Noojin et al.2, in a computed tomography model, found that, although the cross-sectional geometry of the sacral ala was highly variable, there was -sufficient space for iliosacral screws in the vast majority of patients. To ensure safe insertion, iliac screws must be positioned in the geometric center of the sacral ala to avoid extraosseous placement. Bono et al., in a cadaveric model, showed the effect of varying degrees of cephalad displacement on the dimensional constraints of iliosacral screw placement for zone-2 sacral fractures. The authors concluded that exhaustive attempts at reduction must be made because screw placement with residual displacement of 10 mm can endanger the adjacent neural and vascular structures. Several authors have shown electromyographic monitoring to enhance the safety of percutaneous placement of iliosacral screws3. Recent advances in imaging with the use of computer navigation and virtual fluoroscopy give promise that complex pelvic and acetabular injuries can be treated with limited or percutaneous techniques, thereby minimizing complications. Open reduction and stable internal fixation is the treatment of choice for the majority of displaced acetabular fractures in physiologically young patients. Residual displacement of 1 to 2 mm may lead to an increased incidence of posttraumatic arthritis and a poor clinical outcome. The results of previous studies have suggested that complex acetabular fractures are best treated by a limited number of -surgeons who have specialized training and concentrated surgical experience with such injuries. Griffin reported on Matta’s experience with 109 complex acetabular fractures operated upon through the extended iliofemoral approach and followed for a minimum of two years. The author concluded that the percentage of good and excellent results correlated closely with the percentage of anatomic reductions. They also recommended that only surgeons who have the appropriate training and experience should perform these complex procedures. Several authors have reported varying results after open reduction and internal fixation of fractures of the posterior wall of the acetabulum4. Poor outcomes after open reduction and internal fixation are associated with fracture comminution, marginal impaction, and the inability to achieve an anatomic reduction. Moed et al. identified several variables as risk factors for an unsatisfactory result after open reduction and internal fixation of fractures of the posterior wall of the acetabulum. These included an age of more than fifty-five years, a delay of more than twenty-four hours from the time of injury to the time of reduction of a hip dislocation, intra-articular fracture comminution, and residual fracture gaps of >1 cm. Nevertheless, even when internal fixation of acetabular fractures is performed by experienced hands, perioperative complications remain a problem. Karmac et al., in a cadaveric model, showed that intraoperative fluoroscopy with tangential and axial views appears to be an effective method for the evaluation of periacetabular screw location. The advantage of this method of evaluation is that its results can be used immediately, eliminating the risk of reoperation if postoperative radiographs show an intra-articular screw. If postoperative computed tomography scans are used to evaluate possible screw encroachment, then 1-mm slices rather than 3-mm slices should be selected. Heterotopic ossification after an extensile approach to the hip is not uncommon, and it often leads to a decreased range of hip motion and to pain. Burd and Anglen compared the use of indomethacin with localized irradiation for the prevention of heterotopic ossification after acetabular fracture surgery in a prospective, randomized trial of 182 patients. The authors concluded that both focal radiation therapy (800 cGy) within seventy-two hours after surgery and a six-week course of indomethacin (25 mg orally three times a day) were effective modalities in the prevention of heterotopic ossification -after acetabular surgery through posterior and extensile approaches. However, there was no significant difference between the two treatment modalities. The diagnosis and treatment of deep venous thrombosis in patients with pelvic or acetabular fracture remain subjects of controversy. Borer et al. reviewed the records of 486 patients with fracture of the pelvis or acetabulum and found that these patients were at high risk for the development of deep venous thrombosis if no prophylaxis had been used. However, the optimal method for screening patients for deep venous thrombosis remains a subject of debate. Noninvasive magnetic resonance venography, although highly sensitive, has poor specificity. Borer et al. concluded that a positive magnetic resonance venogram should be confirmed with selected venography and that chemical prophylaxis for deep venous thrombosis should be employed. Percutaneous stabilization of acetabular fractures is a demanding procedure and must still be considered experimental. The indications, results, and possible complications of the technique have not been fully delineated. Starr et al. reported the early results and complications after limited open reduction and percutaneous screw fixation of displaced fractures of the acetabulum in twenty-three patients. The authors emphasized the difficulty in obtaining and maintaining an anatomic reduction and suggested limiting the use of percutaneous stabilization to elementary fracture patterns in young patients. Comminuted or complex fractures still require open procedures. However, for elderly patients whose physical demands are lower, the technique may have broader indications for use because imperfect reductions may be more acceptable. The authors concluded that the procedure is best carried out by surgeons experienced in the treatment of acetabular fractures who are skillful in performing reduction maneuvers and in the use of percuta-neous screw techniques. Hip Fractures The incidence of fractures of the hip in the United States continues to rise, with more than 300,000 occurring annually. The cost of treating these fractures is estimated to be sixteen billion dollars per year. Displaced fractures of the femoral neck in elderly patients are devastating injuries that require medical and surgical treatment and consume a considerable amount of health-care resources. The goal of treatment is the restoration of the previous level of function without associated morbidity. Treatment usually consists of hemiarthroplasty or the use of multiple cannulated screws. In a multicenter, prospective, randomized trial conducted in Sweden, 450 active patients who were seventy years of age or older and had a Garden-III or Garden-IV fracture of the femoral neck were randomly assigned to treatment with either internal fixation or arthroplasty. Two years after the operation, the mortality rate was 23%, and the rate of treatment failure was 42% in the internal fixation group (mostly nonunion of the fracture) compared with 6% in the arthroplasty group (mostly recurrent dislocation). There was no significant difference between the groups with regard to their ability to walk, the level of pain, or the rate of mortality or morbidity. Because of the high rate of treatment failure and the poor functional outcomes in the internal fixation group, the authors recommended primary arthroplasty for the treatment of patients at least seventy years of age who have a displaced fracture of the femoral neck. Approximately 50% of hip fractures are intertrochanteric, and a large percentage of those are unstable. Despite the use of improved techniques and devices, failure of compression hip-screw and side-plate fixation is not uncommon. In an effort to reduce the rate of complications associated with the use of compression hip screws, Gotfried5 evaluated the results of the use of a percutaneous compression plate for the treatment of ninety-eight patients with an intertrochanteric fracture. The use of this device resulted in a reduced number of complications, event-free fracture-healing, and an improved level of rehabilitation. Elder et al.6, in a cadaveric model, evaluated the biomechanical effects of fixation augmented with calcium phosphate cement (SRS [Skeletal Replacement System]; Norian, Cupertino, California) for the treatment of unstable intertrochanteric fractures. The authors concluded that augmentation of the fixation with cement significantly improved the overall stability, facilitated the transfer of the load across the fracture, and decreased both the shortening of the proximal aspect of the femur and the stress on the sliding hip screw. However, there was no d-ifference in the load-to-failure rate between the femoral fractures augmented with cement and the control femora. In another experimental cadaveric study, McLoughlin et al.7 performed a biomechanical comparison of dynamic hip screws used with a two-hole side-plate with those used with a four-hole side-plate in a three-part unstable intertrochanteric femoral fracture model. The results of their investigation revealed that the two-hole side-plate was as biomechanically stable as the four-hole side-plate in cyclic and failure loads under the conditions tested. In an effort to improve patient outcomes, many surgeons have been attracted to the use of intramedullary fixation for the treatment of intertrochanteric fractures of the hip, particularly those with a subtrochanteric extension8. Nailing can usually be done as a closed procedure, minimizing trauma at the fracture site. The nail acts as a load-sharing device that permits earlier weight-bearing and rehabilitation. This method of fixation may be particularly useful for comminuted peritrochanteric fractures and for patients who have advanced osteopenia, in whom screw fixation may be precarious. The results of previous randomized studies have shown that an intramedullary hip screw is as effective as a compression hip screw for the management of most intertrochanteric fractures. Use of intramedullary fixation enables surgeons to treat these fractures with a minimally invasive procedure, resulting in high rates of union and low rates of mechanical failure. Femoral Fractures Intramedullary interlocking nailing is the treatment of choice for fractures of the femur in adults. High rates of -fracture union, a low incidence of complications, and an -excellent return of limb function have been documented worldwide. Nevertheless, there is still considerable controversy regarding the appropriate role of intramedullary -reaming and whether the nail should be inserted antegrade or retrograde. Although antegrade femoral nailing remains the standard of treatment, several recent reports have shown that residual hip pain after nailing through the abductor muscles is not uncommon. Furthermore, antegrade nailing is difficult to perform in obese patients and in those with associated injuries to the spine, pelvis, acetabulum, hip, or tibia. Tornetta and Tiburzi9 and Ostrum et al.10 conducted prospective, randomized trials comparing antegrade with retrograde femoral nailing after reaming. The authors of both studies concluded that the union rates for the two techniques were similar and that each technique had its own advantages and disadvantages. The two insertion modes thus appear to be relatively equal in their efficacy for the treatment of fractures of the femoral shaft. However, a longer period of follow-up is necessary to determine whether there are long-term deleterious problems after retrograde nailing of the knee. Ricci et al.11 retrospectively compared retrograde with antegrade nailing of fractures of the femoral shaft and also found no significant differences in rates of union or malunion between the two methods. For the past decade, there has been an ongoing debate about the role of reaming in the treatment of fractures of the femoral shaft, particularly in multiply injured patients with pulmonary injuries. Although the effects are temporary, reaming is associated with some loss of endosteal blood -supply, higher intramedullary pressure, increased pulmonary artery pressure, and transiently decreased pulmonary function. Concern about the systemic pulmonary effects of reaming has led to an increase in the use of nails without reaming. Despite these concerns, the rate of clinically relevant pulmonary dysfunction after intramedullary nailing with reaming is low. The authors of most clinical studies have reported that intramedullary nailing with reaming has not been associated with a concomitant increase in pulmonary complications in multiply injured patients, although this point is still controversial12. In a prospective randomized trial, Tornetta and Tiburzi13 compared the results of -antegrade femoral nailing with reaming with the results of such nailing without reaming in 172 patients. The authors concluded that routine nailing without reaming offered no advantage because fractures, especially those in the distal third of the femur, treated with reaming healed faster than those managed without reaming. In a similar prospective, randomized study, Powell et al. compared intramedullary nailing with and without reaming and found no difference in the prevalence of pulmonary complications (adult respiratory distress syndrome) between the two study groups. In a meta-analysis of studies comparing intramedullary nailing of the femur and tibia with and without reaming, Bhandari et al.14 found that reaming before nailing of fractures of the long bones of the lower extremities substantially reduced the rates of nonunion and of implant failure when compared with nailing without reaming. Nevertheless, additional study is required to determine whether an identifiable subgroup of traumatically injured patients is adversely affected by intramedullary reaming; such a finding would suggest the need for alternative fixation techniques. Supracondylar Femoral Fractures The surgical treatment of supracondylar femoral fractures may be difficult as a result of articular involvement, fracture comminution, injury to the extensor mechanism, and osteoporotic bone. Traditional internal fixation techniques with the use of plates and screws are associated with a small but not irrelevant risk of infection, loss of knee motion, malunion, nonunion, and the need for bone-grafting. Recent emphasis on the preservation of osseous vascularity by use of indirect reduction techniques with a submuscular plate has led to increased rates of union with fewer complications. Nevertheless, the loss of fixation in osteoporotic bone, particularly when a condylar buttress plate is used, remains a problem. In an effort to overcome the loss of fixation with varus angulation, newer methods of osteosynthesis have been developed. The Less Invasive Stabilization System (Synthes, Paoli, Pennsylvania) is under investigation for the treatment of complex fractures of the distal portion of the femur. The -system uses an outrigger device that allows for percutaneous placement of self-drilling cortical shaft screws and locked fixed-angle screws, both proximally and distally, and submuscular placement of the plate. Kregor et al. showed high rates of union, low rates of infection, and maintenance of fixation in patients treated with this method of stabilization. However, difficulties have been reported with regard to the restoration of anatomic alignment at the metaphyseal-diaphy-seal junction by closed reduction. Retrograde intramedullary interlocking nailing is -another useful treatment tool for selected supracondylar femoral fractures. There are strong indications for its use for comminuted extra-articular fractures, in elderly patients with osteoporotic bone, in multiply injured patients, and for periprosthetic fractures that occur proximal to a nonconstrained total knee replacement or distal to a hip implant. Its use for displaced intra-articular fractures, particularly those with coronal or sagittal comminution, remains controversial. The appeal of retrograde nailing for the treatment of supracondylar femoral fractures lies in the potential advantage of a load-sharing implant that is inserted with use of a closed, often percutaneous, technique. The results of numerous studies have shown that, compared with classic internal fixation techniques, intramedullary nailing of supracondylar femoral fractures decreases operating time, blood loss, and the need for bone-grafting while increasing the rate of fracture union. Nevertheless, long-term follow-up studies are necessary to ensure that there is no adverse effect on knee or patellofemoral function. I am not aware of any prospective randomized studies comparing modern techniques of biologic fixation with use of indirect reduction techniques and a submuscular plate with closed retrograde interlocking nailing for supracondylar femoral fractures. Tibial Plateau Fractures Treatment of complex high-energy fractures of the tibial -plateau remains difficult. The goals of treatment of these i-njuries are the restoration of joint congruity, normal alignment, joint stability, and a functional range of knee motion. For markedly displaced bicondylar fractures of the tibial -plateau and those associated with joint instability, conventional open reduction and internal fixation through a single anterior approach has been the standard of care. For many bicondylar fractures of the tibial plateau (Schatzker types V and VI), fixation with two plates may be necessary to prevent axial collapse. However, the soft-tissue stripping in these injuries, together with the surgical dissection needed to apply large plates, has been associated with a high rate of complications, particularly infection and wound breakdown. In an effort to improve the outcome of the repair of high-energy fractures of the tibial plateau, less invasive methods of treatment have been introduced with the use of either tensioned circular wire, hybrid, or large-pin monolateral external fixators or internal fixation through two incisions and use of small-fragment specialized plates. Reid et al.15 studied the placement of proximal tibial transfixation wires used for thin-wire or hybrid external -fixation and the relationship of the wires to the knee joint. Magnetic resonance imaging scans of five fresh cadaver knees and seven knees of volunteer subjects were made after distention of the knee with a gadolinium solution. The distance from the subchondral bone to the insertion of the reflected joint capsule was measured. Although the authors found considerable variability among the knees, the trans-fixation wires that avoided the proximal tibiofibular joint were likely to be extra-articular if they were kept >14 mm from the subchondral bone. Kumar and Whittle16 reported the results of the treatment of fifty-seven Schatzker-type-VI bicondylar fractures of the tibial plateau with use of hybrid external fixation. Closed indirect reduction by ligamentotaxis was attempted for all of the fractures, and limited open reduction was performed for seven. Fifty-four fractures united; forty-five unions were considered anatomic and nine unions were -considered non-anatomic. There were three amputations. The authors concluded that restoration of joint congruity by closed or open means, together with use of a tensioned-wire frame, is appropriate treatment for these difficult -injuries. Marsh et al. reported on the knee function of twenty-two patients (twenty-four knees) five to twelve years after treatment of a high-energy fracture of the tibial plateau with limited internal fixation and large-pin external fixation. Using two generalized health-status instruments (the Short Musculoskeletal Function Assessment and the Short Form-36), they found generally favorable outcomes and a lack of progressive arthrosis. Most of the patients had satisfactory knee stability, a good range of knee motion, and either no or mild nonprogressive arthrosis. High-energy fractures of the tibial plateau can also be treated with a protocol that includes the use of temporary spanning external fixation, articular reduction, and fixation through two incisions with avoidance of extensive soft-tissue dissection. The use of small-fragment and specially designed tibial plateau plates has been found to be helpful as well17. Barei et al. reported the results of internal fixation, with this approach, of comminuted bicondylar fractures of the tibial plateau in forty-seven patients. Although the infection rate was 10.6%, the authors concluded that these injuries can be treated successfully with double plates. Cole and Kregor reported the surgical findings and clinical outcomes of forty-six patients in whom a proximal tibial fracture was treated with a new method, the Less Invasive Stabilization System (Synthes). Clinical trials of this method for the treatment of proximal tibial fractures involving both the lateral and the medial column are under way. The fixator of the Less Invasiv-e Stabilization System has an insertion device that allows- percutaneous submuscular plate fixation and also has a guide for the placement of unicortical self-drilling screws that lock into the plate distal to the fracture, pro-viding -multiple fixed-angle fixation proximally. The Less -Invasive Stabilization System can be thought of as an internal-external fixator; its use for bicondylar fractures of the tibial plateau prevents varus collapse. In the series of Cole and Kregor, use of the Less Invasive Stabilization System led to a 98% rate of union and a 2% rate of infection. Tibial Fractures Nonoperative treatment with casts and functional bracing remains an effective method for the management of isolated, closed low-energy stable fractures of the tibia. Sarmiento18, in a comprehensive review of data on 1000 diaphyseal tibial fractures, found that neither the level nor the type of tibial fracture substantially influenced healing time. However, there was a higher probability of delayed union of fractures that were comminuted or segmental or that occurred as a result of a motor-vehicle accident. Any delay in application of the functional brace resulted in slower healing. Maximum shortening of the fractures occurred at the time of the initial injury, and there was no additional shortening after the introduction of graduated weight-bearing walking. The treatment of unstable closed and open tibial fractures, however, usually requires surgical stabilization. In the past decade, there has been an unmistakable trend toward the use of intramedullary nailing of both closed and open displaced fractures of the tibial shaft and a corresponding decrease in the use of external fixation for these injuries19. The results of recent prospective, randomized studies support the use of nails with reaming for the treatment of unstable closed fractures of the tibia. Compared with the use of small-diameter nails without reaming, nailing with reaming results in higher rates of union and lower rates of malunion, nonunion, and implant failure. Whether the medullary canal should be reamed before a nail is placed in an open tibial fracture is a subject of considerable debate. Many surgeons remain skeptical about the value of reaming in the treatment of acute open tibial fractures. Previous studies have shown that reaming profoundly disrupts the intramedullary blood supply, which was thought to lead to higher rates of infection in open fractures. As a consequence, most surgeons embraced the use of small-diameter nails inserted without reaming for the treatment of acute open tibial fractures, in the belief that infection rates would be lower. However, recent studies have shown that, although infection rates were lower than those reported in historical control studies, a substantial number of high-energy open tibial fractures treated with small-diameter intramedullary nails without reaming required a secondary procedure to achieve union. Furthermore, failure of interlocking screws was a major problem with this technique. The higher prevalence of delayed union after tibial nailing without reaming may be due to the fact that small-diameter nails do not fill the canal, allowing more motion at the fracture site. The use of a larger nail that fills the canal after reaming may increase the mechanical stability at the fracture site, decrease the risk of breakage of the implant and the screw, and paradoxically lessen the risk of infection. Keating et al.20 prospectively studied fifty-seven Gustilo grade-IIIB fractures treated by irrigation, débridement, and immediate nailing with reaming. In this high-risk group of patients, thirteen fractures (23%) were treated with revision nailing and fifteen fractures (26%) required bone-grafting. Infection developed in ten fractures (18%). Because ag-gressive staged reconstruction was possible for these severe injuries, the authors concluded that their results were comparable with or better than the results obtained with nailing without reaming or with use of external fixation. Additional studies, however, will be necessary before nailing with reaming is routinely employed for grade-III open tibial fractures. The success of treatment of open tibial fractures depends in large part upon the optimal treatment of the asso-ciated soft-tissue injury. For the most severe open tibial fractures (grades IIIB and IIIC), soft-tissue reconstruction with a rotational or free tissue transfer is often necessary. However, soft-tissue reconstruction in the zone of injury is not without complications. The Lower Extremity Assessment Project (LEAP) analyzed short-term wound complications after the application of flaps for coverage of traumatic soft-tissue defects about the tibia. The use of a free flap to treat limbs with a severe underlying osseous injury was found to be substantially less likely to lead to a wound complication requiring operative intervention than was the use of a rotational flap21. In an important article, Gopal et al.22 showed that immediate internal fixation and healthy soft-tissu-e coverage with a muscle flap within seventy-two hours after the injury is both safe and effective. Delays in coverage of more than seventy-two hours and the use of external fixatio-n were associated with most of the problems that occurre-d in their series of eighty-four grade-IIIB and grade-IIIC fractures. The success of intramedullary nailing of fractures of the tibial diaphysis has led many surgeons to extend the classic indications for nailing to metadiaphyseal fractures at both ends of the tibia. Unlike fractures of the shaft, in which the nail assists in aligning the fracture, metaphyseal fractures are much more difficult to nail because of the very short segment, the asymmetric muscle forces, and the lack of a friction fit. Good results can be obtained, but they require close attention to detail, subtle changes in the starting point for proximal fractures, use of a femoral distractor, and use of blocking screws to maintain alignment. Newer nail designs and modifications that allow for better control of the small segment by placement of multiple interlocking screws at varying angles also help to maintain alignment. Tibial Pilon Fractures Intra-articular fractures of the distal aspect of the tibia are among the most complex injuries of the leg and represent a major treatment challenge. The best outcomes have been achieved with reconstruction of the articular surface of the tibia, stable internal or external fixation, and a short period of joint immobilization. Marsh et al. reported that fractures of the tibial plafond have a long-term effect on ankle function, pain, and the health-related quality of life. However, the clinical results do not deteriorate over time. Arthrosis is present in the majority of patients but does not correlate with the clinical outcome. Neither fracture pattern, reduction type, nor patient demographics substantially affected the clinical outcome measures. In a series of 100 tibial pilon fractures, Hutson and Zych found treatment with circular tension-wire fixators to be effective, with a rate of fracture union of >90%. The major drawback to this method was the development of pin-track infections; however, the -prevalence of soft-tissue complications such as wound necrosis, dehiscence, and the need for free-tissue transfer was minimal. The failure of hybrid external fixation for the treatment of pilon fractures was analyzed by Watson et al. They noted that monolateral ankle-bridging frames were sufficiently rigid and provided excellent fracture stability. No inherent mechanical failures could be attributed to use of these frames. Three or more metaphyseal wires are necessary for tensioned thin-wire fixators to provide articular stability. Frames with diaphyseal instability and cantilevered loading should be avoided. Untreated comminution and bone loss, as well as a previous open fracture at the metaphyseal-diaphyse-al junction combined with use of a fibular plate, were predictive of failure. The inability to dynamize a hybrid frame with an intact fibula was the primary cause of the complications associated with hybrid fixation, despite adequate frame stability. Another approach to the management of high-energy open and closed pilon fractures with extensive soft-tissue damage is a two-step procedure. In the first stage, primary -reduction and internal fixation of the articular surface is performed with use of limited incisions. Temporary external fixation is applied across the ankle joint. After recovery of the soft tissues, the second stage entails internal fixation with use of less invasive techniques. Several authors have -reported improved outcomes and a decreased rate of complications, particularly infection, with use of a staged method of treatment23. Regardless of the method of treatment, the primary goal of surgery is anatomic realignment of the articular surface. Preoperative computed tomography scans often enable surgeons to improve their understanding of the geometry and displacement of a fracture. With this information, surgical incisions can be carefully planned to avoid excessive dissection and to enhance articular fixation with or without cannulated screws. Foot and Ankle Fractures Pronation-eversion injuries, or Weber-C fractures of the ankle with rupture of the syndesmosis, have traditionally been managed with anatomic reduction and stable internal fixation, with the addition of a syndesmotic screw. Kennedy et al.24 compared two groups of patients in whom a Weber-C ankle fracture was treated surgically: one group was managed with a syndesmotic screw and the other, without it. The addition of a syndesmotic screw provided no benefit, and an additional procedure was required to remove it. Because stainless-steel syndesmotic screws that are not removed can break or can result in substantial osteolysis, Thordarson et al. performed a prospective randomized trial to compare bioabsorbable screws with stainless-steel screws for fixation of the syndesmosis in pronation-external rotation fractures of the ankle. The authors concluded that use of an absorbable polylactic acid syndesmotic screw provided patient outcomes similar to those provided by the stainless-steel screw but obviated the need for subsequent removal. Major fractures of the talus are uncommon. The in-tegrity of the talus is critical to the normal function of the ankle, subtalar, and transverse tarsal joints. Injuries to the head, neck, or body of the talus can interfere with the normal coupled motion of these joints and can result in permanent pain, loss of motion, and deformity. The failure to recognize displacement of a fracture can lead to insufficient treatment and to a poor outcome25. The accuracy of closed reduction of a displaced fracture of the talar neck can be very difficult to assess. Combined anteromedial and anterolateral exposure of fractures of the talar neck can help to ensure -anatomic reduction. Even with early open reduction and internal fixation of displaced fractures of the talus, the prognosis for treatment remains guarded. Recent studies have shown posttraumatic arthritis of both the tibiotalar and the subtalar joint and chronic pain to be common after fractures of the talar neck or body. Avascular necrosis can be expected in more than half of the patients treated, and an open fracture of the talus worsens the prognosis substantially. Few injuries generate as much controversy among fracture specialists as displaced intra-articular fractures of the calcaneus. Infante et al. reported the results of treatment of 635 displaced intra-articular fractures of the calcaneus with open reduction and internal fixation through a single lateral approach. The authors believed that complete restoration of the anatomy of the hindfoot is necessary to achieve a good functional outcome, although surgery does not guarantee one. They reported minimal complications and good functional results in their large series of patients, although they recommended open reduction and internal fixation with primary fusion when a patient has severe cartilage damage. However, in a prospective, randomized clinical multicenter study from Canada, Buckley et al. concluded that operative treatment of displaced intra-articular fractures of the calcaneus is no better than nonoperative treatment. The results of treatment of higher-energy fractures with a lower Böhler angle and more comminution were less satisfactory, regardless of the method used. The nonoperatively treated patients, however, had a larger number of late fusions. The data provided by Buckley et al. suggest that nonoperative treatment is indicated for patients who smoke, who are more than forty years of age, who are noncompliant, who are sedentary, and who receive Workers’ Compensation. Operative treatment was recommended for younger working patients with displaced fractures. Upper-Extremity Fractures
Shoulder Fractures Fractures of the clavicle are extremely common in c-hildren and adolescents, and they usually heal uneventfully with nonoperative management. However, diaphyseal cla-vicular fractures in adults are usually associated with higher-energy- forces, and healing is delayed in 10% to 15% of -patients. Smith et al. conducted the first prospective, ran-domized clinical trial comparing operative and nonoperative treatment of completely displaced midshaft fractures of the clavicle in adults. None of the operatively treated fractures failed to unite, but there were twelve nonunions in the non-operative group, and sixteen patients in that group had some neurologic symptoms with overhead use of the upper extremity, compared with only three patients in the operative group. The authors concluded that internal fixation is a safe, effective method for the treatment of completely displaced fractures of the clavicle. In their randomized study, there were substantially fewer nonunions and neurologic symptoms after internal fixation than after nonoperative treatment. Displaced three-part and four-part fractures of the proximal aspect of the humerus are difficult injuries to evaluate and to treat. Approximately 75% of these injuries occur in patients more than sixty years of age, and there is a strong female predominance. Stable internal fixation of displaced fractures may be difficult to achieve because of the presence of osteoporotic bone and fracture comminution. The choice of treatment is based upon the patient’s physiologic age, the quality of the bone, and the displacement of the fracture. In young patients with good bone quality, open reduction and internal fixation with modern low-profile implants is recommended. Elderly patients and those with poor bone quality are at a greater risk for loss of reduction after open reduction and internal fixation, and they are best treated with early hemiarthroplasty27. Ruch et al.28 performed a biomechanical evaluation of the fixation of experimental three-part fractures of the proximal aspect of the humerus in a cadaveric model. They found that plate-and-screw fixation and locked intramedullary nails provide greater torsional and bending stiffness than fixation with a tension band wire-Ender nail construct. There was no substantial difference between the torsional or bending stiffness associated with the locked intramedullary nail and that associated with the plate-and-screw combination in this model. Hintermann et al.29 reported the results of "rigid" internal fixation of proximal humeral fractures with use of a small blade-plate through a deltopectoral approach in forty-two elderly patients. They found that this implant provided sufficient fracture stability to allow early functional treatment with a low prevalence of avascular necrosis or nonunion. The authors considered this technique to be a viable alternative to hemiarthroplasty for the treatment of selected fractures, even among elderly patients.
Humeral Fractures Although the indications for surgical stabilization of fractures of the humeral diaphysis are reasonably well established, the appropriate method of fixation remains contro-versial. Currently, compression plates and interlocking intramedullary nails are the two most popular devices for achieving fracture stabilization. Open reduction and internal fixation usually ensures a high likelihood of anatomic reduction and union. However, its disadvantages include the need for extensive dissection, the risk of infection, the potential for injury to the radial nerve, the possible mechanical failure in osteoporotic bone, and the possible need for plate removal at a later date. Intramedullary nailing requires less soft-tissue disruption and preserves the fracture hematoma, and reaming can yield autograft materials as well as improved biomechanics. However, the use of intramedullary nails has been associated with postoperative shoulder pain and stiffness due to impingement from prominent implants, and there is a risk of injury to the radial nerve during closed nailing. Two randomized prospective studies of fractures of the humeral shaft compared fixation with dynamic compression plates and fixation with locked intramedullary nails. Chapman et al.31 concluded that plates and nails both provide predictable stabilization and, ultimately, healing of the fracture. Alternatively, McCormack et al.32 concluded that open reduction and internal fixation with plate osteosynthesis was more effective and resulted in fewer complications than intramedullary nailing; therefore, they thought that this method remains the best treatment for unstable fractures of the shaft of the humerus. Because of the biomechanical advantages of closed intramedullary nailing—namely, higher moments of inertia and higher load-sharing capabilities—interest in humeral nailing continues to grow. However, closed insertion of a locked nail (especially after reaming) may put the neurovascular structures (especially the radial nerve) at risk. Mills et al.33 recently showed that intraoperative monitoring of the somatosensory evoked potentials of the radial nerve reliably reflects the status of that nerve in patients undergoing nailing of a humeral fracture. In three of eleven patients, changes in the intraoperative signal prompted a change in the surgical plan. Sanders et al. found that radial nerve injury associated with humeral fractures was directly related to the degree of bone and soft-tissue injury. Patients with high-energy and open fractures of the humerus should be managed aggressively with surgical exploration because of the increased chance that they have a correctable nerve lesion, to improve late outcomes.
Elbow Fractures A surgeon has two options for the management of an unsalvageable comminuted fracture of the radial head: excision or prosthetic replacement. Excision is a well-accepted treatment for isolated fractures of the radial head. However, when a radial head fracture is associated with osseous and soft-tissue injuries to the elbow, the radial head should be preserved whenever possible. Failure to restore the contact compression of the radial head against the capitellum may severely compromise the ability of the lateral and the medial collateral ligament complexes to heal with the proper physiologic tension. Two recent studies have confirmed that acute excision of the radial head provides satisfactory short-term clinical results when there are no associated intra-articu-lar fractures; however, a radial head prosthesis provides lateral osseous support for grossly unstable fractures associated with elbow dislocation and other destabilizing fractures36. Symptomatic loss of motion of the elbow and forearm after an elbow injury is not uncommon. In some patients, a soft-tissue elbow-contracture release may substantially improve function of the elbow. However, the motion achieved at surgery often has been difficult to maintain. Uwe-Lahoda et al. recommended that a release should be performed within nine months after the trauma, with use of continuous passive motion, irradiation, and indomethacin (for the prevention of heterotopic formation) to maintain the surgical result. Hinged external fixation of the elbow to prevent instability and to maintain motion may also be useful, but placement of the -fixator in the true axis of elbow motion is difficult. Frankle compared the results of primary semiconstrained total elbow arthroplasty with cement with the results of the same procedure after failed open reduction and internal fixation in the treatment of comminuted fractures of the distal aspect of the humerus in twenty elderly patients with osteoporotic bone. The authors concluded that the primary total elbow arthroplasty was effective in such patients and that the results were superior to those of the secondary total elbow arthroplasty with respect to the range of elbow motion, the ability to perform activities of daily living, and the results of validated outcome measures.
Forearm and Wrist Fractures A metaphyseal defect is invariably present in comminuted fractures of the distal aspect of the radius. Traditional treatment with a cast, fixators, or Kirschner wires must hold the fracture aligned until the trabecular defect has filled with new bone. If the metaphyseal defect persists after removal of the cast or fixator, late collapse can lead to malunion and to decreased function. Sanchez-Sotelo et al.38 performed a prospective, randomized study of 110 patients more than fifty years of age who had a fracture of the distal aspect of the -radius. They compared the outcome of nonoperative treatment with that of the use of remodelable bone cement -(Norian SRS; Synthes) and immobilization in a cast for two weeks. The patients treated with the bone cement had less pain, earlier restoration of movement and of grip strength, and a better clinical and radiographic result than did those who were treated conventionally. If a distal radial malunion should occur, it can be successfully treated with a three--dimensional osteotomy. In a report on twenty patients with posttraumatic deformity by Jones et al., the corrective procedure improved function as measured by outcome questionnaires and objective radiographic and clinical measurements. Bone-Graft Substitutes The use of bone grafts is an integral part of surgical treatment of fractures associated with comminution, bone loss, or biologic inactivity. Autogenous bone remains the "gold standard" for grafting because of its high biologic activity that usually leads to rapid vascularization and integration. However, in many patients the quantity of bone available for autografting is limited, and donor-site morbidity may be substantial; bone-grafting is also associated with increased operating time, blood loss, and cost. In an effort to decrease the morbidity associated with the harvest of autogenous bone, a variety of bone-graft substitutes have been investigated. Perhaps the most widely used is corticocancellous -allograft bone, which is available in the form of chips, segments, or whole bone. The advantages of allograft bone are that it is widely available, is mechanically strong, and has some osteoinductive properties. It is most commonly used as a metaphyseal filler in a variety of clinical situations, such as filling a defect after the elevation of depressed articular fragments in the treatment of a tibial plateau or pilon fracture. Because of the finite risk of disease transmission, as well as the variable immunogenicity of allograft bone, -alternative substitutes for cancellous bone graft have been developed. Collagen hydroxyapatite, tricalcium phosphate composites, calcium phosphate ceramics, coralline hydroxyapatite, and calcium sulfate have all been successfully used as void fillers, primarily in cancellous bone. However, their lack of osteoinductivity and their poor mechanical support have limited their application in fracture surgery. Bone cements such as methylmethacrylate, Norian SRS (Synthes), and calcium phosphate putty have been widely promoted and used as substitutes for bone graft. These substances provide excellent structural support but lack osteoinductive properties. Furthermore, the United States Food and Drug Administration has not approved Norian SRS except for use in the distal aspect of the radius. More recently, osteoinductive agents such as demineralized bone matrix and bone morphogenetic proteins have become clinically available. These agents are growth factors of high potency, but they provide no structural support and are expensive. Unfortunately, there is a paucity of studies critically comparing the effectiveness and cost of bone-graft substitutes in a variety of clinical situations. The "holy grail" for the ideal bone-graft substitute, one that is osteoconductive, osteoinductive, osteogenic, and mechanically strong, remains elusive. Basic-Science Research In the past decade, there has been a virtual explosion of -basic-science research investigating the regeneration and repair of musculoskeletal tissue. It is beyond the scope of this brief clinical review to document this large body of information in a meaningful way. Advances in molecular biology and tissue-engineering hold great promise that factors that influence fracture-healing or remodeling can be harnessed to improve patient care. Clinicians, scientists, and engineers have developed new techniques for exploring mechanisms in cellular and molecular biology that regulate and repair skeletal tissues. With the advent of regional gene therapy, a broad spectrum of recombinant growth factors, and the preparation of a pool of mesenchymal stem cells, there is growing optimism that, in the future, high-risk fractures and nonunions will be successfully treated through the science of -tissue-engineering.
References
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