Distal Fractures of the Radius 

Distal radius fractures (DRFs) in the time of Hippocrates and Galen were thought to be wrist dislocations. Pouteau first varied from this tradition when he described a variety of forearm fractures in the French literature, including a DRF. As a result, DRFs are termed Pouteau fractures in the French-speaking world. However, politics and communications being what they were, the English-speaking world did not recognize the Pouteau description.

The Irish surgeon Abraham Colles (pronounced collis) described DRFs in the 1814 volume of the Edinburgh Medical Surgical Journal. Colles based his descriptions on clinical examinations alone because radiography had not yet been invented. Despite this limitation, his description of the fracture itself is quite accurate, and his name is most often associated with this fracture in the English-speaking world. Colles stated, "One consolation only remains, that the limb will at some remote period again enjoy perfect freedom in all of its motions and be completely exempt from pain...." This claim that all DRFs, despite displacement, will fare well has been a source of criticism.

Over time, other eponyms have been added to the various subclassifications of DRFs, such as the Smith fracture, Barton fracture, and volar Barton fractures. The fractures are also referred to as various stages of classification systems, such as a Melone IV or an AO (ie, Arbeitsgemeinschaft für Osteosynthese, or Association for the Study of Osteosynthesis) C3 fracture, or are referred to the region of the fracture, such as a chauffeur's fracture.

In current practice, as a result of greater knowledge of the varieties of fracture configurations, eponyms are best avoided and a direct description of the fracture is preferred. The term designation DRF properly covers all fractures of the distal articular and metaphyseal areas. Although all classification systems have serious problems, general agreement exists regarding what some of the classification terms mean, such as the Melone IV or AO C3 fracture, and they do add some degree of specificity and understanding to the generic designation DRF.

The image below depicts a distal radial fracture.

The ultimate goal of treatment is to restore the patient to his or her prior level of functioning. The goal, therefore, is not the same in all patients. For example, a 21-year-old athlete wants to resume competition, but an 82-year-old person usually only wants to return to activities of daily living (ADLs).^{[1, 2]} Because the goals are different, the treatment options are different; but also, because people now remain active until an older age, the definition of "prior level of functioning" is changing. For example, a 92-year-old patient who was being treated in the emergency department had only one concern when conversing with his physician: how soon could he return to playing golf (he had a tournament the next week). Treatment goals, therefore, must be tailored to each patient. Specifically, age should not determine the treatment; the activity level should determine the treatment.

Frequency

Distal radius fractures (DRFs) are among the most common type of fracture, and many authors state that they are the most common type of fracture. DRFs have a bimodal distribution, with a peak in younger persons (aged 18-25 y) and a second peak in older persons (>65 y) persons. The mechanism of injury is unique to each group, with high-energy injuries being more common in the younger group and low-energy injuries being more common in the older group.

Younger patients have stronger bone and require more energy to create a fracture. Motorcycle accidents, falls from a height, and similar situations are common causes for a distal radius fracture (DRF). Trauma is the leading cause of death in the 15- to 24-year-old age group, and this is also reflected in the incidence of lesser traumas.

Older patients have much weaker bones and can sustain a DRF from simply falling on an outstretched hand in a ground-level fall. An increasing awareness of osteoporosis has led to these injuries being termed fragility fractures, with the implication that a workup for osteoporosis should be a standard part of treatment. As the population lives longer, the frequency of this type of fracture will increase.

The pathophysiology of a fracture is rather obvious: more load is imparted than the bone can sustain. However, the patient should be questioned regarding the circumstances of the injury, especially older patients. Heart attacks or transient ischemic attacks can cause a distal radius fracture (DRF) and should not be overlooked. In addition, more problems may be involved with the injury than just the fracture. A useful perspective is that a DRF is a soft-tissue injury surrounding a broken bone, and the immediacy of the radiographic diagnosis should not distract the surgeon from carefully assessing systemic issues or forearm soft-tissue issues.^[3]

The history should be directed toward ascertaining the probable amount of energy involved. A fall from 20 feet can be associated with quite a different constellation of injuries (ie, more than just the fracture seen on the radiograph) from a fall from a standing position. A history of prior fractures should be sought. A history of fragility fractures helps predict the stability of any reduction. A history of multiple high-energy fractures in a younger patient helps predict the ability of the patient to comply with directions.

The median nerve is always compressed after a fall on the palmar aspect of the hand that results in a distal radius fracture (DRF), and the chart note should specifically document the quality (not just the presence or absence) of the median nerve function. Most treatments have median nerve implications. A cast or splint without a reduction may result in median nerve compromise due to pressure. A reduction, whether closed or open, involves some level of anesthesia, temporarily compromising the ability to assess the median nerve. Careful documentation of median nerve function at the first assessment is critical to planning and assessing treatment, not to mention protecting the surgeon from subsequent claims. DRFs are overrepresented in orthopedic malpractice suits.

Introduction to indications

No consensus has been reached on classification systems, indications for surgery, or a particular choice of surgery since the orthopedic community first rejected Colles' contention that all distal radius fractures (DRFs) heal well. Gartland and Werley are generally credited with starting the revolution in 1951 with their paper examining more than 1000 DRFs, and Jupiter brought the discussion into the modern era with his 1986 paper that emphasized the importance of reduction.

Despite the large number of papers published each year on DRFs, no consensus has been reached on treatment and no indications are evident that a consensus might be developing. Indeed, with one approach advocating immediate motion using a fixed-angle volar plate and another advocating motion at 3 months using an internal joint-spanning plate, the treatment options seem to be diverging rather than converging.

One area of agreement is that fractures in active adults should be reduced anatomically; however, unfortunately, the term "anatomically" also has not had any consensus definition.

Even with classification, no consensus has been reached. The International Federation of Societies for Surgery of the Hand formed a working group of the most distinguished minds in DRF management to investigate for the existence of a consensus on the best classification system or, if one did not exist, to develop one. The group concluded that no available system was universally useful or accepted and none could be developed by the working group. Please see the report How to Classify Distal Radial Fractures.

The consensus has been reached that the goal of treatment is to restore the patient to the prior level of functioning, and this is the starting point for all discussion.

Classification

The goals of any classification system are to stratify the injuries, guide treatment, facilitate discussion, and predict outcome. Each classification system has its merits and weaknesses with respect to each goal, and often, more than one classification system is needed. Please see the report How to Classify Distal Radial Fractures.

The classification systems used most frequently are the Frykman, Melone, AO, and Fernandez systems.

• The Frykman classification highlights the injury to the distal radioulnar joint.
• The Melone classification, based on the paper by Scheck, highlights the fragmentation of the articular surface, especially the dorsoulnar corner of the distal radius.
• The AO classification emphasizes the location as extra-articular, partial articular, and completely articular.
• The Fernandez classification is based on the mechanism of injury, deduced from the displacement of the bone and the location of the fracture lines.

A classification system that approaches the topic from another angle categorizes fracture patterns according to the 3-column concept of the wrist and proposes treatment accordingly. This approach was independently developed by Rob Medoff, MD, in 1994 (personal communication) and by Rikli and Rigazzoni.^[4] The 3 columns are the lateral column (the radial half of the radius, including the radial styloid and the scaphoid facet, although Medoff differentiates these 2); the central column (the ulnar half of the radius, including the lunate facet); and the medial column (the ulna, the TFC, and the DRUJ). Each column is considered separately as to its need for reduction and stabilization. It should be noted that this conceptual approach does not exclude any other approaches but, rather, is complementary to them.

Indications for reduction and/or operative treatment

For more information, please see Indications for Reduction in Distal Radial Fractures.

The goal of treatment is to return the patient to prior level of functioning. Most authors advocate an anatomic reduction. This admonition has 2 problems. First, not all patients need an anatomic reduction to be able to resume their normal activities. Second, the concept of anatomic reduction is not defined. No authorities advocate operative reduction if the stepoff is 0.5 mm; however, a stepoff of 0.5 mm is obviously not anatomic. On the other hand, a 20° dorsal tilt is not anatomic, yet inactive elderly adults can easily return to their previous level of functioning with this alignment.

The indications for reduction or operative treatment need to be tailored to the individual patient. Also avoid erring in the opposite direction — that is, considering that any patient who is old does not require an anatomic reduction. Balanced judgment is required.

Most authors would recommend anatomic reduction in a patient who is active in recreation (remember that golf and tennis are common activities for persons older than 70 y.) or engages in forceful activities at work. Conversely, if the patient is sedentary, a lesser reduction may allow return to full activities. Usually, 3 parameters are relevant: intra-articular stepoff, dorsal tilt, and radial length. Radial tilt is generally considered a lesser parameter.

• Intra-articular stepoff

  • Defining anatomic reduction in terms of intra-articular stepoff is challenging. Most authors would accept less than 1 mm of intra-articular stepoff but not more than 2 mm; neutral dorsal tilt but not more than 10° (the range is quite large in the literature, with some authors not accepting more than neutral); and 2 mm of radial shortening but not more than 5 mm. The challenge can be in making a reliable determination of these parameters — that is, how to distinguish between less than 1 mm and greater than 1 mm. Please see Indications for Reduction in Distal Radial Fractures for more information. The challenge is that these opinions are based on studies using routine plain radiographs, which cannot accurately measure stepoffs with an accuracy of 1 mm.
  • The threshold of 1 mm for intra-articular displacement is commonly cited in the literature, referencing a 1986 landmark paper by Knirk and Jupiter.^[5] However, Jupiter has stated repeatedly that this threshold is not the benchmark that subsequent authors have used, that the 1986 study had methodologic flaws, and that ligamentous injuries may better account for the functional limitations of the patients than the intra-articular stepoff. Surgeons need to review the literature with this in mind, because it changes the reliability of the conclusions reached by many authors after 1986.
• Dorsal tilt: Fewer comparative studies have been published on dorsal tilt (both basic science and clinical), but this has not limited authors from making pronouncements. The range of anatomic alignment for dorsal tilt has reportedly been from 0-10°, with no proviso for less active patients. A neutral (0°) alignment represents an 11° loss of volar angulation, so even the most conservative figure is not truly anatomic. Commonly, some older, inactive patients have full resumption of their activities with dorsal tilts of 45° or more. Although orthopedic surgeons may find the radiographs of these patients disturbing and the clinical deformity not much better, some patients are quite satisfied and able to function in all of their ADLs, which calls into question any rigid threshold of dorsal tilt, whether it be 0° or 10°. Most authors recommend no more than neutral to 10° of dorsal tilt in healthy, active individuals.
• Radial length: The basic science of radial length is clear. Shortening of 2 mm of radial length doubles the load through the triangular fibrocartilage and the ulna. The clinical relevance of this fact in the context of distal radius fractures (DRFs) is unclear. Additionally, altering the radius length relative to the ulna affects the function and forces associated with the distal radioulnar joint. On the basis of less well-defined clinical grounds, most authors would not accept more than 2-5 mm of shortening.

Stability of reduction

Another topic that has not been resolved is the stability of the reduction if performed in a closed procedure and without operative support to the fracture fragments. Some authors believe that a 30° dorsal tilt or any radial shortening will not be stable and will subside. If function requires that reduction is achieved, surgery is needed to maintain it.

Agreement has been reached that weekly radiographic assessment is required for approximately 3 weeks. Fractures do not commonly subside after 3 weeks, but this is not a certainty. Care must be observed to compare the current radiograph with the postreduction radiograph because subsidence is gradual and can be difficult to detect.

See the following images for anatomical descriptions of the radius:

Image below shows the volar surface. The large lunate facet is seen on the left, projecting out from the surface of the radius. The volar radial tuberosity is at the right margin of the bone. The surface is covered with the pronator quadratus (PQ). The cortical bone is quite thick and is strong, even in osteoporotic patients.

Image below shows the dorsal surface of the radius. The Lister tubercle is seen in the center. This bone is a thin cortical shell, with little structural strength.

Image below shows the radial surface of the radius.

Image below shows the ulnar surface of the radius, with the sigmoid notch for articulating with the ulna.

Image below shows the distal articular surface of the radius. The scaphoid facet is to the right, and the lunate facet is to the left. This bone is the strongest of all the surfaces, and even if it is osteoporotic, it is quite strong.

Image below shows a normal posteroanterior radiograph of the radius. The ulna is generally within (plus or minus) 2 mm of the radius.

Image below shows a normal lateral radiograph. Note that the center of the lunate facet overlies the volar surface of the bone.

Image below shows anatomic landmarks important for the volar approach to the radius.