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The Journal of Bone and Joint Surgery (American). 2007;89:2051-2062. doi:10.2106/JBJS.G.00020 © 2007 The Journal of Bone and Joint Surgery, Inc.
Management of Distal Radial Fractures1 Massachusetts General Hospital, Yawkey Center, Suite 2100, 55 Fruit Street, Boston, MA 02114. E-mail address for J.B. Jupiter: jjupiter1{at}partners.org
Disclosure: The authors did not receive any outside funding or
grants in support of their research for or preparation of this work. Neither
they nor a member of their immediate families received payments or other
benefits or a commitment or agreement to provide such benefits from a
commercial entity. In support of their research fund, one or more of the
authors received, in any one year, outside funding or grants of in excess of
$10,000 from the AO Foundation, Smith and Nephew, Wright Medical, Small Bone
Innovations, Joint Active Systems, Orthopaedic Trauma Association, and
American Foundation for Surgery of the Hand/American Society for Surgery of
the Hand.
Interest in one of the most common injuries to the musculoskeletal system—the distal radial fracture—has been renewed. Literature over the past two centuries had even led some to believe that the distal radial fracture was a solved problem. In contrast, we are now confronted with a marked swing toward stable internal fixation being touted by some authors as the treatment of choice for all but the most stable, aligned fractures. Instructional courses, symposia, and skills courses worldwide are now oversubscribed, bearing witness to these changing perspectives. It is surprising that, despite this aggressive push toward internal fixation, there is no convincing evidence that supports this approach in the contemporary literature. To what can we attribute this dramatic shift in the management of the distal radial fracture? In this review, we will attempt to answer this question by looking in depth at a number of contributing factors—changing epidemiologic patterns; a growing understanding of the injury mechanism; the development of enhanced imaging techniques; novel plate designs, especially those featuring locked screw fixation; and the impact of patient-rated outcome assessments.
Our basic understanding of the epidemiology of the distal radial fracture and its relationship to general health is maturing. The authors of a prospective, multicenter epidemiologic study estimated the incidence of distal radial fractures to be 36.8/10,000 person-years in women and 9.0/10,000 person-years in men over the age of thirty-five1. Examination of a 5% sample of Medicare claims data from 1986 to 1990 identified 15,000 distal forearm fractures in a cohort of 1.4 million persons2. As life expectancy increases, the incidence of distal radial fractures can be expected to increase as well. On the basis of actuarial risk calculations from Medicare data, the risk of a white woman sustaining a distal forearm fracture was estimated to be 6% by the age of eighty years and 9% by the age of ninety years2. There appears to be a bimodal distribution of distal radial fractures consisting of a younger group who sustains relatively high-energy trauma to the upper extremity and an elderly group who sustains both high-energy injuries and insufficiency fractures. New research has improved our understanding of this second group. According to the 2000 United States Census data, individuals who are sixty-five years of age or older account for 12% of our population. This percentage is expected to balloon to almost 20%, representing 70 million citizens, by 20303. Along with growth of the elderly population is a trend for more individuals in this age segment to live healthier and more active lives4.
In a large patient cohort, the mortality of persons who had sustained a distal radial fracture was either the same as or less than that of the local population. One interpretation of this finding is that individuals who sustain a distal radial fracture are more active and healthier than their age-matched counterparts5. The self-perception of elderly people plays an important role in this increased activity. Many elderly individuals view themselves as being in good health and not disabled4,6. In addition, the proportion of older citizens living independently is growing. A report by the United States Census Bureau stated that 23% of persons sixty-five to seventy-four years of age and 41% of those older than seventy-five lived alone7. Distal radial fracture is also frequently associated with low bone mineral density. Some recent studies have more clearly defined our previous knowledge of this association, especially the relationship of a prior wrist fracture with subsequent osteoporotic fractures at other sites8-10. In women, the risk of a hip fracture increases 1.4 to 1.8-fold if there was a previous wrist fracture. In older men, the risk of hip fracture increases 2.3 to 2.7-fold8,11. Numerous studies have demonstrated increases in mortality after hip fracture12-14. In a similar vein, some have hypothesized that distal radial fracture in an osteoporotic patient could be associated with decreased survival. The existence of such a subpopulation is supported by a study demonstrating increased mortality in a small cohort of patients, greater than sixty-five years of age, who sustained a distal radial fracture15. These patients had an average of more than three comorbidities, with two of the most frequent three being musculoskeletal and cardiac. Thus, while many older individuals are leading more active lives, the high prevalence of osteopenia and osteoporosis places this segment of the population at a particularly high risk for distal radial fracture. With today's active elderly, it can be expected that both high-energy injuries and insufficiency fractures will occur, and results of treatment will be confounded by the presence of agerelated osteopenia or frank osteoporosis. The impact of distal radial fractures on society can be anticipated to increase over time; as a result, considerable scientific, clinical, and economic interest in the treatment of these fractures has developed.
Part of the trend toward internal fixation is due to an improved understanding of the structural anatomy of the distal part of the radius and the kinematics of the wrist and distal radioulnar joint. In addition, a greater understanding of the patterns of injury is leading to treatment based on the specifics of each individual injury.
Historical studies emphasized quantitative parameters that define an
acceptable reduction of a distal radial fracture. In 1951, Gartland and Werley
reported a landmark study on the evaluation of healed Colles fractures that
emphasized restoration of volar tilt to 11° and radial inclination to
23° to "compensate adequately for the loss of correction which will
occur" when Colles fractures are treated with closed
means16. They
defined a Colles fracture as a dorsally displaced metaphyseal fracture of the
distal part of the radius with or without articular involvement. Fractures
that settled tended to be associated with a worse functional outcome. A
subsequent study of malunited distal radial fractures compared with
anatomically healed distal radial fractures demonstrated that grip strength,
range of motion, and the ability to perform activities of daily living were
significantly worse (p < 0.05) in patients with dorsal angulation of
>12° than in those with dorsal angulation of
Biomechanical studies of simulated distal radial malunions have been performed in an attempt to explain why these parameters have clinical importance. Studies of cadavers have demonstrated an increase in radiocarpal contact areas and pressures with radial shortening; dorsoulnar migration of contact pressures with increased dorsal inclination; and shifts in the instant center of rotation during pronation and supination with changes in radial height, inclination, and dorsal angulation18-20. In the past, the principles of management of distal radial fractures have focused on restoring these parameters, and restoration of global alignment is heavily weighted in many physician-rated outcome assessments. Contemporary investigations have focused in greater depth on the mechanism of the fracture and its relationship to various articular injury patterns, the impact of the fracture on carpal kinematics and the function of the distal radioulnar joint, and the biomechanics of angular stable fixation21-26.
Radiocarpal Stability Biomechanical investigations have demonstrated how fractures occur and the association of these fractures with intercarpal ligament injury. A cadaver study21 in which a hyperextension load was applied to the distal part of the radius demonstrated the following sequence of events: (1) the flexor tendons are tensed, leading to increased pressure over the carpus; (2) the palmar radiocarpal and ulnocarpal ligaments and variable intercarpal ligaments are tensed and rupture; (3) there is dorsal impingement of the carpus on the radial joint surface; and (4) the dorsal aspect of the metaphysis reaches its yield point and fractures. A separate finding was that the scaphoid impinges on the carpus primarily with hyperextension, but there may be a considerable load on the lunate facet (Fig. 1). In twenty-eight of forty cadavers, the investigators identified a number of intercarpal ligament injuries as well as different intra-articular fracture patterns due in part to the differential impact of the scaphoid and lunate with hyperextension. These findings must be interpreted with caution. Because the mechanism of injury occurs through the radioscaphoid articulation, this articulation is not necessarily the major contributor to stability. Previous in vitro studies suggested that radioscaphoid contact is greater than radiolunate contact18, but subsequent in vivo studies suggested that the radiolunate articulation accepts a greater amount of contact than had been previously acknowledged27. This renewed emphasis on the importance of the radiolunate articulation coincides with the development of a structural concept that the distal part of the radius consists of a medial, an intermediate, and a lateral column (Figs. 2-A and 2-B)28. This theory emphasizes that (1) the lateral, or radial, column is an osseous buttress for the carpus and is an attachment point for the intracapsular ligaments; (2) the intermediate column functions in primary load transmission; and (3) the medial, or ulnar, column serves as an axis for forearm and wrist rotation as well as a post for secondary load transmission. Clinical failures of volar plate fixation of the distal part of the radius have also provided some insight into the subtleties of distal radial anatomy29. The volar surface of the distal part of the radius is flat until the distal end of the pronator quadratus, where the distal rim of the radius is more anterior in the region of both the radial styloid and the lunate facet (Fig. 3)30. Because of the difficulties with supporting the very distal lunate facet fragments in the treatment of some fractures, changes have been made in a number of volar locking plate designs.
Carpal Kinematics It is still not clear why posttraumatic radiocarpal arthritis develops in some patients and not in others. Residual intra-articular incongruity has been accepted as a predictor of the development of radiographically evident arthritis31. However, studies with seven and fifteen-year durations of follow-up of patients with an intra-articular fracture have demonstrated that function is well-preserved as evaluated with validated outcome measures, despite evidence of arthritic changes on radiographs32,33.
The alignment of the carpus in relation to the distal radial articular surface after healing may also be an important factor in the outcomes of treatment of distal radial fractures32. In a prospective study of distal radial fractures treated with closed reduction, external fixation, or open reduction and internal fixation, the authors found that carpal alignment—the displacement of the capitate relative to the longitudinal axis of the radius—was the most important predictor of function. It is likely that the interplay between carpal kinematics and longitudinal alignment has an important influence on fracture outcomes. Another potential contributor to altered radiocarpal kinematics is intercarpal ligament injury. In a study in which a hyperextension force was applied to sixty-three cadaveric wrists until a distal radial fracture occurred, an injury to the triangular fibrocartilage complex occurred in 63% (forty) of the specimens, an injury to the scapholunate interosseous ligament occurred in 32% (twenty), and an injury to the lunotriquetral ligament occurred in 17% (eleven)21. These in vitro observations have been validated clinically: tears of the scapholunate ligament, lunotriquetral ligament, and triangular fibrocartilage complex are commonly noted during arthroscopically assisted reduction and internal fixation of distal radial fractures34,35. As our understanding of carpal kinematics has advanced, it has become evident that the carpal bones interact in an elegant and intricate pattern and it has been suggested that these kinematics may be disrupted by articular step-off, radiocarpal malalignment, or intercarpal ligament injury. Recognition of these factors is an additional explanation for a growing trend toward operative treatment of displaced fractures.
Distal Radioulnar Joint
While not yet supported by adequate scientific data, it has been evident clinically to many that instability of the distal radioulnar joint is uncommon when the radial fracture has been reduced anatomically and supported by stable plate fixation. When the distal interosseous membrane was divided in a cadaver model, stability of the distal radioulnar joint was compromised41. Some believe that the distal radioulnar joint becomes unstable only when the distal interosseous membrane is injured42. Future research is needed to determine how much influence injury to the distal interosseous membrane has on the outcome of treatment of a distal radial fracture.
Imaging These oblique radiographic views as well as computed tomography and three-dimensional computed tomography reconstructions have had a major impact on decision-making, with a move toward creative intervention and internal plate fixation, especially when the volar lunate facet is rotated (Figs. 4-A and 4-B)44-46. When four independent observers reviewed thirty different intra-articular fractures on two separate occasions, the addition of a computed tomography scan and a three-dimensional computed tomography reconstruction to the standard radiographs led to the observers recommending operative treatment in 50% of the cases23. Although computed tomography scanning is costly and certainly not routine in general practice, it has become more affordable and available. Orthopaedic surgeons in the future may find that advanced imaging studies are further encouraging them to perform operative intervention for distal radial fractures.
It has been long recognized that there is a correlation between the functional outcome following a distal radial fracture and the restoration of both the radiocarpal and the radioulnar relationships24,31. What has been less predictable has been the maintenance of the reduction of fractures in osteopenic bone or fractures considered to be unstable. The development of angular stable fixation techniques with use of implants designed specifically for the anatomy of the distal end of the radius theoretically improves our ability to manage these problems (Figs. 5-A, 5-B, 5-C, 5-D).
The important aspects of angular stable fixation are: (1) stability is not achieved by the creation of friction between the plate and bone as in traditional screw-plate fixation, but rather mechanical bridging of the bone and load-bearing are allowed through the locked screw-plate construct; (2) locking-head screws do not rely on the bone thread for purchase; and (3) screws that lock into the plate prevent loosening within the implant, so early failure of fixation with an angular stable implant will occur only if the entire screw-plate construct pulls out from the bone or there is material failure of the implant25.
The concept of angular stable fixation of distal radial fractures is actually not new as a number of different implants used over the past two decades have involved this technology26. Contemporary enthusiasm for the application of these implants can be attributed in part to the angular stable fixation but perhaps more so to the recognition that the more prevalent dorsally displaced fractures can be internally fixed from the palmar side. Theorized benefits of volar plate fixation, especially for more simple dorsally displaced fractures, include (1) ease of anatomic reduction because the volar cortex is often less comminuted than the dorsal side of the injury, (2) early return of hand and upper-limb function, (3) diminished frequency and duration of formal occupational therapy, (4) potentially less overall pain, (5) a decreased risk of displacement, and (6) potential cost savings secondary to a diminished need for radiographs47,48. Many of these benefits would be derived from the inherent stability of the fixed-angle plate-screw construct.
Biomechanical studies have emphasized the need for placement of the
distalmost screws or pegs just beneath the subchondral bone of the articular
surface to achieve the maximum benefit of volar fixed-angle plate fixation. In
a cadaver model, when distal screw fixation was placed Currently, more than thirty different implant designs are produced worldwide. The growing popularity of internal fixation has yielded numerous options with regard to plate material, contour, and shape; locking and nonlocking features; and cost. An estimated $2 billion in medical costs are incurred as a result of distal radial fractures, and this is associated with a $250 million market in medical devices aimed toward treatment of these injuries50. A large portion of this cost is due to fact that fixation with locked volar plates involves machining of threaded holes in the plate and matching threaded screw heads. This rapidly evolving industry requires careful scrutiny as these changes are based on a limited amount of stringent clinical evidence. Case series documenting these new technologies continue to be published and represent possible trends in the future; however, Level-I and II evidence is required to delineate the true benefits that these new technologies and their additional costs confer to patients.
Over the past decade, a deliberate and profound philosophical change in orthopaedics has redirected evaluation measures toward the patient's self-reporting of treatment outcomes. In the late 1980s and early 1990s, a global health survey called the Short Form-36 (SF-36) was created to collect large cross-sectional pools of normative data with which comparisons can be made51. Although this scale is aimed toward measuring general health and chronic disease, it seems to have some validity for evaluating wrist injuries. The SF-36 consists of subscales evaluating physical role, bodily pain, social functioning, and other components of general health. One study showed that the physical role and mental health domains were responsive indices three months following treatment of Colles fractures with closed reduction52. A subsequent study demonstrated that the physical component and mental component summary scores were significantly lower (p < 0.01) for patients who had intra-articular displacement of  1 mm on the most recent
radiographs53. The
findings in the latter study most likely reflect the development of arthrosis
in the wrist, as the most recent radiographs were made about two years
postinjury.
Other patient-rated evaluations have been developed. The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire is intended to evaluate upper-extremity outcomes, and the Patient-Rated Wrist Evaluation (PRWE) is aimed toward disorders of the wrist54,55. Modified self-reporting systems such as the QuickDASH and the visual QuickDASH recently have been validated56,57. In a prospective evaluation of the SF-36, DASH, and PRWE along with standard physical performance measures for assessing recovery after distal radial fractures treated with a variety of methods, the PRWE was found to be a more responsive measure than the DASH and both indices were more responsive than the SF-36. Notably, the function subscales of the PRWE were the most responsive between the time of the initial injury and the three-month follow-up examination, and grip strength was the most responsive physical performance measure. The association between grip strength and the PRWE was reaffirmed by independent studies58. There are important caveats with regard to the interpretation of the results of evaluations performed with these systems. The DASH scores may be confounded by concomitant lower-extremity injury59. The inability of a patient to reach a door or an inability to stabilize the trunk and shoulder girdle may affect DASH items such as turning a key or carrying a shopping bag. In addition, the DASH and SF-36 scores may be heavily influenced by pain60. When applied to disorders of the elbow, the DASH as well as the physical and mental component scores of the SF-36 were statistically correlated (p < 0.001) with higher pain subscale scores on the American Shoulder and Elbow Surgeons (ASES) evaluation61, which requires summation of ratings for pain at its worst, at rest, during lifting, during repetitive motions, and at night60. Other instrument measures not specifically related to the upper extremity have also been used to evaluate outcomes after a distal radial fracture. The Physical Activity Scale for the Elderly (PASE) instrument is a validated measure of the overall activity and functional demand in a one-week period. This instrument is based on a regression of a component score derived over three days of monitoring 277 adults with a mean age of seventy-four years. The scale ranges from 0 to 400, with a higher score indicating greater activity62. Treatment of a distal radial fracture with internal fixation in patients older than sixty years of age was associated with a mean PASE score of 17763 compared with a mean PASE score of 118 in an uninjured elderly population64. The emphasis on patient-rated outcomes reflects a global shift in how operative treatments are evaluated. Rather than patients understanding their outcomes on the basis of the surgeon's satisfaction with a procedure, surgeons evaluate their outcomes on the basis of the patient's satisfaction with the result. Consequently, global health, arm and wrist function, and return to activity have supplanted traditional measures such as strength and range of motion. Today's patients, including active elderly individuals, are demanding outcomes that restore their perceived preinjury wrist and hand function. These new outcome measures are arguably more accurate and reliable indicators than traditional evaluation systems. While yet to be reproducibly demonstrated in Level-I or II studies regarding the outcome of volar plate fixation of simple extra-articular fractures, there is a growing impression that, from a patient's perspective, an early return to functional independence may be the single most important impact of internal fixation of these fractures. By three to six months postoperatively, there may not be any major difference between the results of treatment modalities. This was shown to be the case in a multicenter study by Cassidy et al., who used implantable Skeletal Repair System (SRS) cement (Norian, Cupertino, California) for immediate fixation and encouraged motion within ten days and compared the results with those of alternative methods with a minimum of six weeks of immobilization65. The patients treated with Norian SRS cement had a significant improvement (p < 0.05) in their SF-36 scores during that critical six weeks.
Prospective, Randomized, Controlled Trials In a Cochrane review of randomized, controlled studies until the year 2000, it became evident that the majority of studies suffered from methodological deficiencies66. Most series included a small number of patients and, as a consequence, were unlikely to demonstrate strong evidence to support one treatment option over another. A second criticism was that allocation concealment—i.e., blinding of evaluators with regard to the group to which the patients had been randomized—was deficient in forty-two of forty-four so-called randomized studies. As a result, it is difficult to extrapolate robust data from the studies available prior to 2000. Despite these limitations, the authors of the Cochrane study were able to draw one major conclusion: studies included in their systematic review suggested that external fixation and percutaneous pin fixation have better radiographic outcomes and may have better functional outcomes when compared with cast immobilization. Considering the quality of the available literature, major questions remain: (1) Is external fixation or percutaneous pin fixation a better intervention than closed treatment when evaluated with validated outcome measures? (2) How does open reduction and internal fixation compare with external fixation and percutaneous pin fixation or even closed reduction and cast immobilization? (3) Is there a particular technique for each treatment modality that provides superior results? (4) As most recent studies include only a maximum of two years of follow-up, do the results of treatment endure over the long term? Recent randomized, controlled trials have begun to clarify some of these questions. A series of eighty-five patients prospectively randomized to be treated with bridging external fixation or with closed reduction and plaster cast immobilization demonstrated statistically equivalent Gartland and Werley functional scores after seven years of follow-up; however, radiographic measures were significantly better in the external fixation group (p < 0.001)67. When validated outcome scores were used to compare spanning external fixation with closed reduction and cast immobilization of distal radial fractures without joint incongruity in 113 patients, SF-36 bodily pain scores and Musculoskeletal Function Assessment (MFA) scores at two years favored external fixation; however, these trends did not reach significance68. In a study of fifty-seven patients, radiographic parameters after percutaneous pin fixation were found to be significantly better than those after closed reduction (p < 0.05); however, there was no difference in SF-36 scores69. In a subsequent study, although augmented external fixation and percutaneous pin fixation resulted in similar validated outcome scores and functional outcomes at one year, the patients treated with external fixation demonstrated better articular congruity on radiographic follow-up70. In two Canadian studies, open reduction and internal fixation was compared with external fixation for displaced, unstable intra-articular fractures. One of these was a prospective, randomized, controlled trial in which dorsal pi-plate fixation was compared with external fixation with limited reduction and pin fixation in sixty-two patients71. There were no significant differences in DASH scores or SF-36 scores; however, the pi-plate group had significantly weaker grip strength and a higher number of complications, especially tendinitis and the need for hardware removal (p = 0.004). In the other study, a prospective randomized trial, external fixation with indirect reduction and percutaneous pin fixation was compared with open reduction and internal fixation in 179 patients72; although MFA and SF-36 scores at two years were statistically equivalent between the groups, external fixation yielded better outcomes at the six-month interval. The authors concluded that, if articular congruity can be established through indirect means, external fixation may be preferable because of an earlier return of function. What is unclear is when occupational therapy was initiated for the internal fixation group and whether this factor may have affected the study results. The authors72 also contended that, because outcome scores and functional results appear stable after one year, there is no need to pursue a two to five-year follow-up. Although primary outcomes may become stable, potential midterm complications of volar plate techniques such as irritation of the flexor pollicis longus by the implants or carpal tunnel syndrome may become apparent in the future. Despite evidence that validated outcome scores may not change after the one-year mark, midterm follow-up may have independent value and should continue to be performed and reported. Studies comparing locked volar plate fixation with external fixation are ongoing and may help to distinguish whether a locked volar plate provides additional benefit. One case-control study comparing use of a volar fixed-angle plate with external fixation in thirty-two patients demonstrated better radiographic outcomes with use of the plate (p < 0.05) but no difference in the DASH or PRWE scores73. From these studies, the following inferences can be made regarding plates: (1) external fixation augmented with percutaneous pin fixation yields better radiographic results than closed reduction or percutaneous pin fixation alone; (2) internal fixation yields radiographic results and two-year clinical results that are comparable with those of augmented external fixation; and (3) because internal fixation yields radiographic results that are comparable with those of external fixation, internal fixation can be expected to provide radiographic results that are better than those of closed reduction or percutaneous pin fixation. Although these studies have yielded useful data, a large, long-term, prospective, randomized, controlled trial in which validated outcome measures are used to compare different treatment modalities is needed to test the assumption that strict anatomic reduction by open reduction and plate fixation better supports the intermediate column, improves carpal mechanics, and as a result decreases radiocarpal arthrosis. Until that study is completed, there is little Level-I evidence to suggest that any form of internal fixation with a plate is superior to augmented external fixation for the majority of unstable extra-articular or intra-articular fractures.
Biomechanics Two biomechanical studies in which a cadaver distal radial fracture model was subjected to physiologic loads have demonstrated that enhancing external fixation with Kirschner wires improves stability only to a point74,75. This enhancement is substantially lessened when there is a more complex intra-articular fracture. The studies showed that, when augmented external fixation is used for complex intra-articular fractures, it is less stable than small-plate-and-pin fixation directly applied to the fracture fragments. Biomechanical studies have also been done to evaluate different types of internal fixation devices. In two studies, plates applied on the volar surface with use of angular stable fixation screws or pegs that lock into the plate were compared with alternative plate-fixation techniques in an extra-articular fracture model76,77. The fixed-angle plates demonstrated increased single load to failure and increased stiffness during cyclic loading when compared with dorsal plates and volar plates without fixed-angle support. In another study, fixed-angle volar plate fixation was compared with the use of small plates applied directly on the fracture fragments in an intra-articular fracture model78. When the constructs were subjected to cyclical loading and single load to failure, the stiffnesses of the two types of fixation were similar in most cases. However, specific fixation of the dorsal ulnar fragment with additional orthogonal fixation from the radial side added significant stiffness (p < 0.05) when compared with that provided by a fixed-angle volar plate alone. Although there is a dearth of strict prospective, randomized studies or biomechanical data indicating clear superiority of one treatment modality over another, there continues to be a strong push toward anatomic reduction and internal fixation especially on the volar side with use of angular stable fixation. It is remarkable that this trend toward internal fixation is so strongly driven without clear scientific evidence supporting it.
As the method of internal fixation of distal radial fractures changes, the frequency and types of complications as well as our treatment of complications can be expected to change as well. Complications of distal radial fractures include compressive neuropathy, malunion, tendon rupture, radioulnar and radiocarpal arthrosis, pain syndromes, and finger stiffness. Other complications include flexor or extensor tendon entrapment in the fracture or the distal radioulnar joint and the development of palmar fascial nodules79. Although the use of volar plates and low-profile dorsal plates may limit tendon irritation, these techniques do not entirely eliminate the problem. With volar plate fixation, irritation of the flexor carpi radialis and flexor pollicis longus tendon by the plate itself as well as dorsal tendon irritation from screw prominence have been reported80. Early in the experience with the use of volar plates, frank rupture of the extensor pollicis longus was reported in two patients81. No cases of extensor tenosynovitis were observed in two series of patients treated with a low-profile dorsal plate; however, superficial extensor retinacular scarring requiring extensor pollicis longus tenolysis and two cases of metaphyseal screw loosening requiring removal were reported82,83. There has also been increased attention on the possibility of ischemic contracture of the pronator quadratus as a potential complication leading to limited forearm rotation after distal radial fracture, or specifically after fixation with a volar plate and tight repair of the pronator quadratus. Although this entity was considered theoretical in the past, case reports have documented both isolated pronator quadratus compartment syndrome and compartment syndrome associated with a minimally displaced distal radial fracture84,85. Isolated pronator quadratus compartment syndrome presents as pain with passive supination and pronation. In theory, ischemic injury could lead to contracture and limited supination. An important caveat is that, while use of a locked volar plate is an acceptable treatment for distal radial fractures, there are fracture patterns that are not amenable to these techniques. As mentioned previously, small volar lip fractures are important to recognize and can be a source of fixation failure. Loss of fixation of the volar lunate facet was documented in two independent reports24,80. A locked volar plate augmented with a second radial buttress plate provides a stiffer construct than does a volar plate alone and may have utility in the treatment of a fracture with severe metaphyseal comminution86. Double-plate fixation was reported to have acceptable outcomes at two years postoperatively; however, plate removal was common in that cohort87. Some surgeons have utilized a distraction plate technique, with use of a long 3.5-mm plate spanning the radial shaft to the long finger metacarpal, for fractures with severe metaphyseal-diaphyseal comminution88. Use of a volar plate when other techniques are more suitable could result in poor outcomes. The advent of volar plate fixation has also influenced treatment of distal radial malunion. Traditionally, a nonlocking plate was applied in a buttress mode to support the osteotomy site and bone graft89. The choice of a volar or dorsal buttress was based on the direction of the malunion. With volar locking constructs, an osteotomy can be performed through a volar approach, even for dorsally angulated malunions. In a case series of dorsally angular distal radial malunions treated with a fixed-angle volar plate and followed for one year, DASH scores were comparable with those following internal fixation of acute distal radial fractures90.
Many things are subject to trend and fashion, and the treatment of distal radial fractures is no exception. Pins and plaster gave way to external fixation, and now internal fixation has begun to supplant all other treatment modalities. Novel fields of research, epidemiologic and sociologic changes, and new implant designs are driving this new trend toward plate fixation. However, the future of treatment of distal radial fractures depends on solid research. There is a need for well-designed clinical, biomechanical, and cost-benefit studies to compare locking plate systems with other treatments. Ultimately, the current enthusiasm for volar fixed-angle plates should be tempered until outcomes and advantages are securely validated by hard science.
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Top
Introduction
Scope of Impact
The older population
continues to grow and, at the same time, live more active lives; as a
consequence, the incidence of distal radial fractures can be expected to
increase. 
10°
