Internal fixation versus other surgical methods for treating distal radius fractures in adults
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To compare the effects (benefits and harms) of internal fixation versus other methods of surgical intervention (percutaneous pinning; external fixation) for distal radius fractures in adults.
Our main comparisons will be:
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internal fixation versus method of surgery that is not internal fixation; i.e. percutaneous pinning or external fixation or a combination of these two methods
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internal fixation versus percutaneous pinning
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internal fixation versus external fixation
Background
Description of the condition
The distal end of the radius, which is the end nearest the wrist, is one of the most common places for fractures or broken bones in adults (Chung 2001). Often termed wrist fractures, distal radius fractures are commonly defined as fractures occurring within three centimetres (approximately one inch) of the distal end of the radius (Chung 2001).
In the developed world, the incidence of distal radius fracture appears to be increasing (De Putter 2011; Hagino 1999; Melton 1998; Thompson 2004). A UK‐based multicentre study of patients aged 35 years and above with distal radius fractures reported an annual incidence of 9 per 10,000 men and 37 per 10,000 women (O'Neill 2001). Before the age of 40, the incidence is higher in men (Singer 1998). In women, the incidence increases with age, especially after the age of 40 years (Broadbent 2003). It has been estimated that at 50 years of age a white woman in the USA or Northern Europe has a 15% lifetime risk of a distal radius fracture, whereas a man has a lifetime risk of just over 2% (Cummings 1985). In the USA, distal radius fractures account for up to 18% of all fractures in the over‐65 age group (Baron 1996).
While young adults usually sustain distal radius fractures following high‐energy trauma, the injury usually results from low‐energy trauma in older people, especially women. A fall from standing height onto an outstretched hand is the leading cause of this injury (Flinkkilä 2011; Sigurdardottir 2011).
Following injury, people present with immediate pain around the distal radius, swelling, bruising, crepitus (crackling, grating or popping sounds and sensations), as well as wrist deformity if the fracture is displaced. In the majority of cases, the fracture is closed (the skin surrounding the fracture is not breached), but a small proportion of people have an open wound exposing the fracture. This is termed an 'open fracture'. Some people with distal radius fractures may present with alteration in finger sensation if there has been compression of the median nerve due to soft tissue swelling or haematoma (bleeding from the fracture) or an associated nerve injury. Radiographs (X‐rays) are generally used to confirm the diagnosis and plan the management. In complex fracture cases, a computerised tomography (CT) or magnetic resonance imaging (MRI) may be used to clearly delineate the fracture and associated injuries.
It is difficult to quantify precisely the impact of distal radius fractures in terms of lost work hours and short and long term disability for the population studied. A review by Polinder 2013 of the costs of upper extremity injuries in adults estimated the direct costs, adjusted to 2007 values, of wrist fractures to be 1890 Euro per case. This study also showed higher costs for women (2440 Euro) than men (1150 Euro). People with distal radius fractures are usually managed as outpatients, but it has been estimated that around 20% of patients (mainly older people) require hospital admission (Cummings 1985; O'Neill 2001).
Classification
Surgeons have classified fractures by anatomical configuration and fracture pattern to aid communication, research and guide management. Simple classifications were based on clinical appearance and often named after those who described them (eponyms). A 'Colles’ fracture' is one of the common distal radius fractures, typically occurring following a fall on the outstretched hand. Patients present with the characteristic distal forearm 'dinner fork deformity', which indicates a dorsally displaced, dorsally angulated, dorsally comminuted (multiple fragments) and radially shortened distal radius fracture. Others, such as Barton and Smith, added their descriptive classifications for specific fracture patterns. Distal radius fractures can be simply classified as either displaced or undisplaced, extra‐articular (not involving the wrist joint) or intra‐articular (fractures involving the wrist joint), dorsal and volar displaced fractures and distal radius fractures with or without fracture of ulnar styloid.
There has been a move towards using structured classification systems to define distal radial fractures instead of eponyms or simple descriptors. Ideally, a fracture classification system enables consistent description of the fracture, helps with communication between doctors and aids in the management of the fracture (Fernandez 2001). Jupiter 1997 presented a comprehensive review of the many available fracture classification systems used for these fractures. Brief descriptions of six of the most commonly cited classification systems are in Table 1 (Cooney 1993; Fernández 1993; Frykman 1967; Melone 1993; Müller 1991; Older 1965).
| Name (reference ID) | Brief outline | Comment |
| AO (Arbeitsgemeinschaft für Osteosynthesefragen) (Müller 1991) | This system is organised in order of increasing fracture severity. It divides the fractures into three major groups:
These three groups are then subdivided, yielding 27 different fracture types. | There is no assessment of the extent of fracture displacement |
| Fernández (Fernández 1993) | This system is based on the mechanisms of injury. There are five main groups:
These groups are further categorised by stability, displacement pattern, number of fragments (or comminuted) and associated lesions. | The injury mechanism is not always apparent. There is no consideration of the extent of displacement |
| Frykman (Frykman 1967) | This system distinguishes between extra‐articular fractures and intra‐articular fractures of the radiocarpal and radio‐ulnar joints, and the presence or absence of an associated distal ulnar (ulnar styloid) fracture. | There is no assessment of the extent or direction of fracture displacement, or of comminution |
| Melone (Melone 1993) | This system identifies five fracture types, based on 4 major fracture components: the radial shaft, the radial styloid, and the dorsal‐ medial and volar‐medial fragments. | This is for intra‐articular fractures only |
| Older (Older 1965) | This system divides fractures into four types, labelled I to VI (1 to 4) of increasing severity. The types are defined according to extent of displacement (angulation and radial shortening) and comminution. | There is no consideration of radio‐ulnar joint involvement |
| Universal Classification (Cooney 1993) | This system divides fractures into four main types, labelled I to VI (1 to 4), distinguishing between extra‐articular and intra‐articular fractures and displaced and non‐displaced fractures. Displaced fracture types II and IV are further subdivided based on reducibility (whether the fracture can be reduced; that is whether the bone fragments can be put back in place) and stability (whether, once reduced, the fragments will remain so). | This does not distinguish between the radiocarpal and radio‐ulnar joints. Additionally, there is a 'trial by treatment' |
Complications
Complications from distal radius fractures are not uncommon and can arise from either the injury itself or following the treatment provided. Immediate complications following the fracture include associated ligament injury (Geissler 1996), the triangular fibrocartilagenous complex (TFCC) injury (Lindau 2000) and acute carpal tunnel syndrome (compression of median nerve from fracture haematoma) (Belsole 1993). Attrition rupture of extensor pollicis longus (thumb extensor tendon) has been associated with minimally displaced distal radius fractures (Bonatz 1996 ; Helal 1982). Complex regional pain syndrome type 1 (a constellation of symptoms such as swelling, excessive pain, skin colour changes and stiffness) occurs in 1% of patients with non‐operative treatment and up to 5% of patients who have an operation (Atkins 2003). Malunion, which may result from redisplacement of an initially reduced fracture, can result in midcarpal instability (dynamic instability resulting from malaligned bones in the midcarpal joint). These changes in the radiocarpal, midcarpal and radioulnar joints can lead to pain (Patton 2004), loss of motion (Kazuki 1993) and reduction in grip strength (Patton 2004), along with the development of later degenerative changes (Park 2002; Taleisnik 1984). In addition, arthritis of the wrist can result from the malunion of intra‐articular distal radius fractures. Although a strong correlation has been noted between maximum step displacement in articular fragments and the development of arthritis, no significant correlation has been found between the patients' radiological and functional status (Catalano 1997; Forward 2008; Goldfarb 2006).
Complications resulting from surgical treatment rather than the injury itself are diverse and frequent. They include infection, tenosynovitis (inflammation of the synovial lining of the tendon), rupture of flexor and extensor tendons from prominent metalware, complex regional pain syndrome type 1, iatrogenic nerve or blood vessel injury, delayed union or malunion, screw loosening and intra‐articular screw positioning or displacement (Arora 2007).
Description of the intervention
Non‐surgical (conservative) treatment of distal radial fractures typically comprises manipulation of the displaced fractures (closed reduction) and wrist or forearm immobilisation for several weeks in an external cast or brace. However, the results of non‐operative management, particularly in older people with bones weakened by osteoporosis, are not consistently satisfactory (Handoll 2003). This has resulted in the development of other strategies involving surgery, which are aimed at more accurate reduction and more reliable stabilisation.
The four main strategies for surgical treatment are internal fixation, percutaneous pinning, external fixation and use of bone grafts and substitutes (Fernandez 1996). These methods may be used alone or in a combination with each other. For example, in cases of comminution or bone loss, the distal radius fixation may need to be supplemented with bone grafts or bone graft substitutes to fill the bone defects. Cochrane Reviews examining the evidence for fixation using percutaneous pins (Handoll 2007a), external fixation (Handoll 2007b; Handoll 2008a) and bone grafts and substitutes (Handoll 2008b) are already available. A separate Cochrane Review that aims to compare internal fixation versus conservative treatment and different methods of internal fixation is underway (Hoare 2014). Descriptions of the three main methods of fixation are given below.
Internal fixation
Internal fixation generally requires an open approach to directly visualise the fracture. Either a volar (palm side of the forearm) or dorsal approach (back of the forearm) is used for the surgery. Intra‐operative imaging in the form of X‐rays is commonly used to aid visual assessment of reduction and placement of devices. Stabilisation with plates is the most common type of internal fixation and there are many different types on the market. The reduction of the fracture can be achieved manually before applying a plate or can be assisted by applying a plate on distal end of the fracture and then reducing the plate on to the shaft of the radius. Plates can be applied on the volar, dorsal or radial surfaces of the distal radius (Orbay 2004; Rikli 1996) and can be used singly or in combination according to the fracture pattern and fragments involved. More recently designed plates are generally anatomically pre‐contoured for their specific position on the bone. Plates may be either locking (the screw heads themselves screw into the plate to act share the load) or non‐locking. A rarer method on internal fixation is intramedullary nailing, where a nail is inserted into the canal in the centre of the radius and usually secured by screws. These devices are usually inserted through a minimally invasive approach (Brooks 2006) and their use is usually limited to extra‐articular fractures or intra‐articular fractures with fragments large enough to be reduced anatomically by closed means.
Percutaneous pinning
In percutaneous pinning, pins or Kirschner wires (K‐wires) are inserted percutaneously (through the skin) into the distal radius fracture to help reduce and hold the fracture. K‐wires can be used in a myriad of ways (Rayhack 1993). The two main ways are intra‐focal (Kapandji 1988) or intra‐fragmentary. The former uses the K‐wire as a joystick (reduction tool), placing the tip of the wire in the fracture then levering the fracture fragments into a satisfactory position. The other more commonly used method is to reduce the fracture by closed means and then stabilise the reduced fracture with K‐wires holding (fixing) the fracture fragments together. Following the percutaneous pinning, the wrist is usually immobilised in a plaster cast for additional stability. The K‐wires are generally left in for about four to six weeks but may be removed early if causing any problems such as infection.
External fixation
When using external fixation, fractures are generally reduced without the need for an open approach to visualise the fragments. Percutaneouly inserted K‐wires may be used to augment the reduction. Threaded pins are inserted into the bone either sides of the fracture and secured onto a frame or incorporated into a plaster of Paris cast to maintain the reduction. The threaded pins are inserted through small skin incisions. There are many external fixator systems available. Uniplanar or multiplanar designs allow the fracture to be manipulated and stabilised in one or many planes. The threaded pins can be placed either side of the wrist joint in a "bridging" mode with threaded pins in the metacarpals distally and the radius more proximally. In a "non‐bridging" mode, threaded pins are inserted either side of the fracture without spanning the wrist joint. Some external fixation designs incorporate a hinge at the level of the wrist joint to enable early wrist movement whilst maintaining fracture reduction (Capo 2006; Fernandez 1999).
How the intervention might work
In this Cochrane Review, we plan to compare internal fixation with the two other main surgical methods of fixation, namely percutaneous pinning and external fixation. All three methods aim to restore anatomy and stabilise the fractured parts to enable healing to take place. It is widely supposed that open reduction and internal fixation will provide superior anatomical restoration and fixation than either of the other methods that use closed reduction methods. However, internal fixation is more invasive, more complex to perform and more costly, particularly in comparison with percutaneous pinning, which is minimally invasive, versatile and relatively simple and quick to perform and is considerably less expensive (Shyamalan 2009).
All three approaches share the common risk of surgery‐related complications, such as of infection and risk of injury to neurovascular structures and tendons but to varying extents. For example, pin track infection is common for both percutaneous pinning and external fixation and careful management of the pin tracks is required to avoid this. Rupture of flexor and extensor tendons from prominent metalware is a well documented complication of plate fixation. Fixation failure, especially in osteoporotic bone, is of concern for all three methods but the development of angular stable plating systems, using locking screw technology has reduced the risk of collapse of already weakened bone as the load is transmitted through the screws and plate (McFadyen 2011). There is also a greater risk of fixation failure in osteoporotic bone for pinning and external fixation as pins, or external fixation, or both, can lose hold in the thin cortices (Trader 1979). For both percutaneous pinning and external fixation, the pins and wires are removed after fracture stabilisation or earlier where there are complications. These are relatively straightforward procedures but the removal or adjustment of a plate is more involved and invasive.
The increased stability attained by internal fixation with locking plates has the anticipated advantage of earlier mobilisation, which can translate into better function (McFadyen 2011). However, many patients usually have a period of wrist immobilisation after internal fixation in order to lower the risk of fixation failure. Moreover, superior anatomical results do not necessarily produce better function and quality of life: there is a poor correlation between radiological findings and functional or clinical outcome (Bentohami 2013; Finsen 2013).
Why it is important to do this review
Distal radius fractures are one of the most common injuries in adults. While there is a lack of consensus on their management (Lichtman 2010), there has been a significant increase in the use of internal fixation; for example, a 13‐fold increase was reported between 1998 and 2008 in Finland (Mattila 2011). In particular, there has been a trend to treat older patients presenting with osteoporotic fractures with internal fixation using locking plates (Chung 2009). There is a need to compare internal fixation with the other commonly used surgical methods for treating distal radius fractures, namely percutaneous pinning and external fixation, either alone or in combination with each other, in order to identify which surgical method for treating these fractures gives the best clinical and patient‐rated outcomes.
Objectives
To compare the effects (benefits and harms) of internal fixation versus other methods of surgical intervention (percutaneous pinning; external fixation) for distal radius fractures in adults.
Our main comparisons will be:
-
internal fixation versus method of surgery that is not internal fixation; i.e. percutaneous pinning or external fixation or a combination of these two methods
-
internal fixation versus percutaneous pinning
-
internal fixation versus external fixation
Methods
Criteria for considering studies for this review
Types of studies
We will include randomised controlled trials (RCTs), quasi‐RCTs (which use a method of allocating participants to a treatment that is not strictly random, e.g. by date of birth, hospital record number, alternation) and controlled clinical trials that evaluate internal fixation compared with other methods of surgical fixation for treating distal radial fractures in adults.
Types of participants
Skeletally mature patients of either sex with a fracture of the distal radius. We will include trials that recruit adults and children if we can obtain separate data for adults or the proportion of children is small (< 5%). We will only include trials containing different fracture types if separate data are available for participants with distal radial fractures. We will also include trials recruiting people whose fractures have redisplaced within two weeks of conservative management.
Types of interventions
We will include trials comparing internal fixation versus other surgical methods, such as external fixation, for treating these fractures and intend to make the following comparisons:
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Internal fixation versus other method of surgery that is not internal fixation
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For this comparison, we plan to present subcategories according to main treatment methods of the control group: i.e. 'other method', percutaneous pinning, external fixation or a combination of these two methods.
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Internal fixation versus percutaneous pinning
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Our primary subcategories will be for percutaneous pinning: transfixation of the fracture fragments or Kapandji pinning.
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Internal fixation versus external fixation
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Our primary subcategories will be for external fixation: non‐bridging versus bridging of the radiocarpal joint.
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There are many types of each of the main methods of surgery, such as volar versus dorsal plating for internal fixation, and the use of supplementary methods, such as bone graft for bony voids or additional pinning for external fixation, on an individual basis. These add unavoidable complexity. To allow for this variation in practice, we have set out primary comparisons that cover the defining categories of surgery (e.g. internal fixation, external fixation), with a prior specification of the main subcategories for the control groups that we will present within each category. The use and selection of subcategories and additional categorisation based on types of internal fixation (intramedullary nailing versus plating; volar versus dorsal plating; fragment specific versus fixed‐angle plating) or augmentation of internal fixation with bone grafts or bone graft substitutes or wiring (such as for ulnar styloid fractures) will depend on the comparison but also, in part, on the availability of trials in terms of testing for subgroup differences.
Types of outcome measures
Primary outcomes
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Limb‐specific patient‐reported outcome measures of function: such as the Disability of the Arm, Shoulder and Hand questionnaire (DASH) (MacDermid 2000), the Patient Evaluation Measure (PEM) (Forward 2008), the Patient Related Wrist Evaluation (PRWE) (MacDermid 2000)
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General measures of health‐related quality of life such as the Short Form‐36 (SF‐36) (MacDermid 2000)
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Adverse events – we will attempt to differentiate these into:
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Serious adverse events requiring substantive treatment such as surgery or prolonged therapy (e.g. deep infection, tendon rupture, symptomatic malunion, CRPS‐1, long‐term pain)
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Minor adverse events (e.g. short‐term pain, superficial infection, asymptomatic malunion)
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Secondary outcomes
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Hand and wrist function measures such as the Jebsen‐Taylor score (Sears 2010) or the Gartland and Werley score (Gartland 1951)
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Grip strength
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Range of movement (wrist and forearm mobility): range of movement for the wrist is described in terms of six parameters: flexion (ability to bend the wrist downwards) and extension (or upwards); radial deviation (ability to bend the wrist sideways on the thumb side) and ulnar deviation (on the little finger side); and pronation (ability to turn the forearm so that the palm faces downwards) and supination (palm faces upwards)
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Return and time to return to usual occupation and activities of daily living
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Patient satisfaction with cosmetic appearance
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Pain ‐ assessed by self report such as analgesic requirements or score on a visual analogue scale
Other outcomes
We will record radiological parameters including radial length, dorsal and radial angulation, ulnar variance and intra‐articular step or gap (see Table 2). (Note: these may not correlate with patient‐reported measures). We will also look for any use of resources data including hospital stay, outpatient attendances and other costs.
| Parameters | Definition | Normal values |
| Dorsal angulation (dorsal or volar or palmar tilt) | Angle between: a) the line which connects the most distal points of the dorsal and volar cortical rims of the radius; and b) the line drawn perpendicular to the longitudinal axis of the radius. Side view of wrist. | Palmar or volar tilt: approximately 11 to 12 degrees |
| Radial length | Distance between: a) a line drawn at the tip of the radial styloid process, perpendicular to the longitudinal axis of the radius; and b) a second perpendicular line at the level of the distal articular surface of the ulnar head. Frontal view. | Approximately 11 to 12 mm |
| Radial angle or radial inclination | Angle between: a) the line drawn from the tip of the radial styloid process to the ulnar corner of the articular surface of the distal end of the radius; and b) the line drawn perpendicular to the longitudinal axis of the radius. Frontal view. | Approximately 22 to 23 degrees |
| Ulnar variance | Vertical distance between: a) a line drawn parallel to the proximal surface of the lunate facet of the distal radius; and b) a line parallel to the articular surface of the ulnar head. | Usually negative variance (e.g. ‐1 mm) or neutral variance |
Timing of outcome measurement
We will categorise the timing of outcome measures into short term (within three months), medium term (over three months to one year) and long term (over one year). Most immediate or resolvable adverse events will manifest within the short‐term time frame and the long‐term time frame should allow an assessment once fracture union has occurred in most people.
Search methods for identification of studies
Electronic searches
We will search the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to present), the Cochrane Central Register of Controlled Trials (in The Cochrane Library, current issue) (see Appendix 1), MEDLINE (1946 to present), and EMBASE (1974 to present). We will also search Current Controlled Trials, the WHO International Clinical Trials Registry Platform and will not apply any language restrictions.
In MEDLINE (Ovid Online), we will combine the search strategy with the sensitivity‐maximising version of the Cochrane Highly Sensitive Search Strategy for identifying randomised trials (Lefebvre 2011; see Appendix 1). The search strategies for The Cochrane Library and EMBASE are also in Appendix 1.
Searching other resources
We will search the reference lists of published included trials for other relevant articles. We will handsearch various relevant meeting abstracts, including: British Society for Surgery of the Hand and the British Orthopaedic Association Congress using supplements of the The Bone and Joint Journal (previously the Bone and Joint Journal ‐ British); American Society for Surgery of the Hand; American Academy of Orthopaedic Surgeons; American Orthopaedic Trauma Association; and the Federation of European Societies for Surgery of the Hand.
Data collection and analysis
Selection of studies
Two review authors (ARP and PAS) will independently screen the search results for potentially eligible trials using a proforma. We will resolve any disagreements through discussion and, if necessary, by consulting the other authors (ACJ and ACW). Once we have excluded any obviously irrelevant studies through an initial screening, we will obtain the full text articles of the remaining studies. ARP and PAS will independently perform study selection, and consult ACJ and ACW should any disagreements not be resolved through discussion. We will document reasons for inclusion or exclusion of studies at this stage. We will attempt to translate any potentially eligible non‐English language papers. If this is not possible, we will list these studies in the 'Studies awaiting classification' section.
Data extraction and management
Two review authors (from ACJ, ARP and PAS) will independently extract data from the included trials using a piloted data extraction form. We will resolve any disagreements through discussion and, if necessary, by consulting AW. Data will be entered into Review Manager software (RevMan) (RevMan 2012) by ACJ, ARP and PAS. We will attempt to contact authors of published and unpublished trials for any missing information or additional information.
Assessment of risk of bias in included studies
Two review authors (from ACJ, ARP and PAS) will independently assess the risk of bias of included trials using the Cochrane 'Risk of bias' tool (Higgins 2011a), which has seven domains: random sequence generation; allocation concealment; blinding of participants and personnel; blinding of outcome assessment; selective outcome reporting; incomplete outcome data; and other potential sources of bias. We will consider the risks of specific bias relating to surgical trials, including differences in the level of experience of surgeons delivering the interventions under comparison, and the funding of trials by industry. Each item will be evaluated as being at low, high or unclear risk of bias in accordance with the criteria as listed in Table 8.5.d of Higgins 2011a; see Table 3). We will consider subjective outcomes (e.g. self‐reported function and quality of life outcomes, pain) and objective outcomes (e.g. complications, re‐operation) separately in our assessment of blinding and completeness of outcome data. We will resolve any disagreements by discussion or arbitration by AW. Titles of journals, names of authors or supporting institutions will not be masked.
| Random sequence generation: selection bias (biased allocation to interventions) due to inadequate generation of a randomised sequence | |
| Risk of bias | Criteria for this judgement |
| Low | The investigators describe a random component in the sequence generation process such as:
*Minimisation may be implemented without a random element, and this is considered to be equivalent to being random. |
| High | The investigators describe a non‐random component in the sequence generation process. Usually, the description would involve some systematic, non‐random approach, for example:
Other non‐random approaches happen much less frequently than the systematic approaches mentioned above and tend to be obvious. They usually involve judgement or some method of non‐random categorization of participants, for example:
|
| Unclear | Insufficient information about the sequence generation process to permit judgement of 'low' or 'high' risk of bias. |
| Allocation concealment ‐ selection bias (biased allocation to interventions) due to inadequate concealment of allocations prior to assignment | |
| Risk of bias | Criteria for this judgement |
| Low | Participants and investigators enrolling participants could not foresee assignment because one of the following, or an equivalent method, was used to conceal allocation:
|
| High | Participants or investigators enrolling participants could possibly foresee assignments and thus introduce selection bias, such as allocation based on:
|
| Unclear | Insufficient information to permit judgement of 'low' or 'high' risk. This is usually the case if the method of concealment is not described or not described in sufficient detail to allow a definite judgement – for example if the use of assignment envelopes is described, but it remains unclear whether envelopes were sequentially numbered, opaque and sealed. |
| Blinding of participants and personnel ‐ performance bias due to knowledge of the allocated interventions by participants and personnel during the study | |
| Risk of bias | Criteria for this judgement |
| Low | Any one of the following:
|
| High | Any one of the following:
|
| Unclear | Any one of the following:
|
| Blinding of outcome assessment ‐ detection bias due to knowledge of the allocated interventions by outcome assessors | |
| Risk of bias | Criteria for this judgment |
| Low | Any one of the following:
|
| High | Any one of the following:
|
| Unclear | Any one of the following:
|
| Incomplete outcome data ‐ attrition bias due to amount, nature or handling of incomplete outcome data | |
| Risk of bias | Criteria for this judgement |
| Low | Any one of the following:
|
| High | Any one of the following:
|
| Unclear | Any one of the following:
|
| Selective reporting ‐ reporting bias due to selective outcome reporting | |
| Risk of bias | Criteria for this judgement |
| Low | Any of the following:
|
| High | Any one of the following:
|
| Unclear | Insufficient information to permit judgement of 'low' or 'high' risk. It is likely that the majority of studies will fall into this category. |
| Other bias ‐ bias due to problems not covered elsewhere in the table | |
| Risk of bias | Criteria for this judgement |
| Low | The study appears to be free of other sources of bias. |
| High | There is at least one important risk of bias. For example, the study:
|
| Unclear | There may be a risk of bias, but there is either:
|
1Taken from Table 8.5.d in Higgins 2011a
Measures of treatment effect
We will present dichotomous outcomes as risk ratios with 95% confidence intervals (CIs) and continuous outcomes as mean differences with 95% CIs. We will present standardised mean differences with 95% CIs when pooling continuous data based on different scales or scores.
Unit of analysis issues
The unit of randomisation in these trials is usually the individual patient. Exceptionally, as in the case of trials including people with bilateral fractures, data for trials may be presented for fractures or limbs rather than individual patients. Where such unit of analysis issues arise and appropriate corrections have not been made, we will present the data for such trials only where the disparity between the units of analysis and randomisation is small. Where data are pooled, we will perform a sensitivity analysis to examine the effects of excluding any trials with analyses that have not been corrected for this unit of analysis issue.
We will avoid unit of analysis issues related to repeated observations of the same outcome, such as results presented for several periods of follow‐up.
Dealing with missing data
For trials published since 2000, we will attempt to contact the original trial authors to request missing data. Where possible, we will analyse data on an intention‐to‐treat basis as per initial randomisation. Loss of participants from the trials will be investigated with an analysis of best and worst case scenarios. We will be alert to the potential mislabelling or non‐identification of standard errors and standard deviations. We will derive missing standard deviations from other statistics (CIs, standard errors, exact P values) if these are available; otherwise we will not assume or impute missing values. We will undertake sensitivity analyses, such as best and worst case scenario analyses, to assess the effect of missing data on final results.
Assessment of heterogeneity
We will assess heterogeneity by visual inspection of the forest plot (analysis), alongside consideration of the test for heterogeneity and the I² statistic (Higgins 2003). We will base our interpretation of the I² results on Higgins 2011b: 0% to 40% might not be important; 30% to 60% may represent moderate heterogeneity; 50% to 90% may represent substantial heterogeneity; and 75% to 100% may represent very substantial heterogeneity.
Assessment of reporting biases
If sufficient data are available (at least 10 trials), we will attempt to assess publication bias by preparing a funnel plot. Funnel plot asymmetry will be evaluated visually in the first instance. Our searches for grey literature and trials listed in clinical trial registers should also help us to assess publication bias.
Data synthesis
If appropriate, we will pool results of comparable groups of trials using both fixed‐effect and random‐effects models. Our choice of model to report will be guided by careful consideration of the extent of heterogeneity and whether it can be explained, in addition to other factors, such as the number and size of included trials. We will use 95% CI throughout. We will consider not pooling data where we detect considerable heterogeneity (I² > 75%) that cannot be explained by the diversity of methodological or clinical features among trials. Where it is inappropriate to pool data, we will present trial data in the analyses or tables for illustrative purposes and report these in the review text.
Subgroup analysis and investigation of heterogeneity
We plan to perform subgroup analyses by age (under 50; 50 or above), sex, type of fracture (primarily, extra‐articular versus intra‐articular; dorsal versus volar displacement), and key subcategories of the main treatment methods within 'control' interventions (e.g. for percutaneous pinning: transfixation of the fracture fragments versus Kapandji pinning; for external fixation: non‐bridging versus bridging external fixation; for internal fixation: volar versus volar plating, and fragment specific versus fixed‐angle plating).
We will investigate whether subgroup results differ significantly by inspecting the overlap of CIs and by performing the test for subgroup differences available in RevMan (RevMan 2012).
We will specify our expectations of the direction and the size of treatment effect for different subgroups before performing subgroup analysis. For example, we anticipate that older and female patients, in whom osteoporosis is more common, will have a better outcome with locking plate fixation than percutaneous pinning.
Sensitivity analysis
Where possible, we will conduct sensitivity analyses examining various aspects of trial and review methodology, including the effects of missing data, of excluding trials at high or unclear risk of bias (specifically, selection bias from lack of allocation concealment, detection bias from lack of outcome assessor blinding, and performance bias from disparity between the intervention groups in the experience of the operating surgeons), trials only reported in abstracts, and trials with unit of analysis problems related to the inclusion of participants with bilateral wrist fractures; and the selection of the statistical model (fixed‐effect versus random‐effects model).
Assessing the quality of the body of evidence
We will use the GRADE approach to assess the quality of evidence related to the key outcomes (primary outcomes plus the first four secondary outcomes) listed in the Types of outcome measures (Chapter 12, Section 12.2, Schünemann 2011). For details of how the assessment will be made, see Table 4; Table 5; Table 6; and Table 7.
| Methodology | GRADE quality of evidence |
| RCTs; or double‐upgraded observational studies | High |
| Downgraded RCTs; or upgraded observational studies | Moderate |
| Double‐downgraded RCTs; or observational studies | Low |
| Triple‐downgraded RCTs; or downgraded observational studies; or case series or case reports | Very low |
1Copy of Table 12.2.a (Schünemann 2011)
| Factors that may decrease the quality level of a body of evidence1 |
| 1. Limitations in the design and implementation of available studies suggesting high likelihood of bias |
| 2. Indirectness of evidence (indirect population, intervention, control, outcomes) |
| 3. Unexplained heterogeneity or inconsistency of results (including problems with subgroup analyses) |
| 4. Imprecision of results (wide CIs) |
| 5. High probability of publication bias |
1Copy of Table 12.2.b (Schünemann 2011)
| Factors that may increase the quality level of a body of evidence1 |
| 1. Large magnitude of effect |
| 2. All plausible confounding would reduce a demonstrated effect or suggest a spurious effect when results show no effect |
| 3. Dose‐response gradient |
1Copy of Table 12.2.c (Schünemann 2011)
| GRADE quality of evidence | Explanation |
| High | Further research is very unlikely to change our confidence in the estimate of effect |
| Moderate | Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate |
| Low | Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate |
| Very low | We are very uncertain about the estimate |
'Summary of findings' tables
Where there is sufficient evidence, we will prepare 'Summary of findings' tables for the main comparisons: internal fixation versus percutaneous pinning; internal fixation versus external fixation; internal fixation alone versus any of the above methods in combination with bone grafting, or bone substitute, or both.
| Name (reference ID) | Brief outline | Comment |
| AO (Arbeitsgemeinschaft für Osteosynthesefragen) (Müller 1991) | This system is organised in order of increasing fracture severity. It divides the fractures into three major groups:
These three groups are then subdivided, yielding 27 different fracture types. | There is no assessment of the extent of fracture displacement |
| Fernández (Fernández 1993) | This system is based on the mechanisms of injury. There are five main groups:
These groups are further categorised by stability, displacement pattern, number of fragments (or comminuted) and associated lesions. | The injury mechanism is not always apparent. There is no consideration of the extent of displacement |
| Frykman (Frykman 1967) | This system distinguishes between extra‐articular fractures and intra‐articular fractures of the radiocarpal and radio‐ulnar joints, and the presence or absence of an associated distal ulnar (ulnar styloid) fracture. | There is no assessment of the extent or direction of fracture displacement, or of comminution |
| Melone (Melone 1993) | This system identifies five fracture types, based on 4 major fracture components: the radial shaft, the radial styloid, and the dorsal‐ medial and volar‐medial fragments. | This is for intra‐articular fractures only |
| Older (Older 1965) | This system divides fractures into four types, labelled I to VI (1 to 4) of increasing severity. The types are defined according to extent of displacement (angulation and radial shortening) and comminution. | There is no consideration of radio‐ulnar joint involvement |
| Universal Classification (Cooney 1993) | This system divides fractures into four main types, labelled I to VI (1 to 4), distinguishing between extra‐articular and intra‐articular fractures and displaced and non‐displaced fractures. Displaced fracture types II and IV are further subdivided based on reducibility (whether the fracture can be reduced; that is whether the bone fragments can be put back in place) and stability (whether, once reduced, the fragments will remain so). | This does not distinguish between the radiocarpal and radio‐ulnar joints. Additionally, there is a 'trial by treatment' |
| Parameters | Definition | Normal values |
| Dorsal angulation (dorsal or volar or palmar tilt) | Angle between: a) the line which connects the most distal points of the dorsal and volar cortical rims of the radius; and b) the line drawn perpendicular to the longitudinal axis of the radius. Side view of wrist. | Palmar or volar tilt: approximately 11 to 12 degrees |
| Radial length | Distance between: a) a line drawn at the tip of the radial styloid process, perpendicular to the longitudinal axis of the radius; and b) a second perpendicular line at the level of the distal articular surface of the ulnar head. Frontal view. | Approximately 11 to 12 mm |
| Radial angle or radial inclination | Angle between: a) the line drawn from the tip of the radial styloid process to the ulnar corner of the articular surface of the distal end of the radius; and b) the line drawn perpendicular to the longitudinal axis of the radius. Frontal view. | Approximately 22 to 23 degrees |
| Ulnar variance | Vertical distance between: a) a line drawn parallel to the proximal surface of the lunate facet of the distal radius; and b) a line parallel to the articular surface of the ulnar head. | Usually negative variance (e.g. ‐1 mm) or neutral variance |
| Random sequence generation: selection bias (biased allocation to interventions) due to inadequate generation of a randomised sequence | |
| Risk of bias | Criteria for this judgement |
| Low | The investigators describe a random component in the sequence generation process such as:
*Minimisation may be implemented without a random element, and this is considered to be equivalent to being random. |
| High | The investigators describe a non‐random component in the sequence generation process. Usually, the description would involve some systematic, non‐random approach, for example:
Other non‐random approaches happen much less frequently than the systematic approaches mentioned above and tend to be obvious. They usually involve judgement or some method of non‐random categorization of participants, for example:
|
| Unclear | Insufficient information about the sequence generation process to permit judgement of 'low' or 'high' risk of bias. |
| Allocation concealment ‐ selection bias (biased allocation to interventions) due to inadequate concealment of allocations prior to assignment | |
| Risk of bias | Criteria for this judgement |
| Low | Participants and investigators enrolling participants could not foresee assignment because one of the following, or an equivalent method, was used to conceal allocation:
|
| High | Participants or investigators enrolling participants could possibly foresee assignments and thus introduce selection bias, such as allocation based on:
|
| Unclear | Insufficient information to permit judgement of 'low' or 'high' risk. This is usually the case if the method of concealment is not described or not described in sufficient detail to allow a definite judgement – for example if the use of assignment envelopes is described, but it remains unclear whether envelopes were sequentially numbered, opaque and sealed. |
| Blinding of participants and personnel ‐ performance bias due to knowledge of the allocated interventions by participants and personnel during the study | |
| Risk of bias | Criteria for this judgement |
| Low | Any one of the following:
|
| High | Any one of the following:
|
| Unclear | Any one of the following:
|
| Blinding of outcome assessment ‐ detection bias due to knowledge of the allocated interventions by outcome assessors | |
| Risk of bias | Criteria for this judgment |
| Low | Any one of the following:
|
| High | Any one of the following:
|
| Unclear | Any one of the following:
|
| Incomplete outcome data ‐ attrition bias due to amount, nature or handling of incomplete outcome data | |
| Risk of bias | Criteria for this judgement |
| Low | Any one of the following:
|
| High | Any one of the following:
|
| Unclear | Any one of the following:
|
| Selective reporting ‐ reporting bias due to selective outcome reporting | |
| Risk of bias | Criteria for this judgement |
| Low | Any of the following:
|
| High | Any one of the following:
|
| Unclear | Insufficient information to permit judgement of 'low' or 'high' risk. It is likely that the majority of studies will fall into this category. |
| Other bias ‐ bias due to problems not covered elsewhere in the table | |
| Risk of bias | Criteria for this judgement |
| Low | The study appears to be free of other sources of bias. |
| High | There is at least one important risk of bias. For example, the study:
|
| Unclear | There may be a risk of bias, but there is either:
|
| 1Taken from Table 8.5.d in Higgins 2011a | |
| Methodology | GRADE quality of evidence |
| RCTs; or double‐upgraded observational studies | High |
| Downgraded RCTs; or upgraded observational studies | Moderate |
| Double‐downgraded RCTs; or observational studies | Low |
| Triple‐downgraded RCTs; or downgraded observational studies; or case series or case reports | Very low |
| 1Copy of Table 12.2.a (Schünemann 2011) | |
| Factors that may decrease the quality level of a body of evidence1 |
| 1. Limitations in the design and implementation of available studies suggesting high likelihood of bias |
| 2. Indirectness of evidence (indirect population, intervention, control, outcomes) |
| 3. Unexplained heterogeneity or inconsistency of results (including problems with subgroup analyses) |
| 4. Imprecision of results (wide CIs) |
| 5. High probability of publication bias |
| 1Copy of Table 12.2.b (Schünemann 2011) |
| Factors that may increase the quality level of a body of evidence1 |
| 1. Large magnitude of effect |
| 2. All plausible confounding would reduce a demonstrated effect or suggest a spurious effect when results show no effect |
| 3. Dose‐response gradient |
| 1Copy of Table 12.2.c (Schünemann 2011) |
| GRADE quality of evidence | Explanation |
| High | Further research is very unlikely to change our confidence in the estimate of effect |
| Moderate | Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate |
| Low | Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate |
| Very low | We are very uncertain about the estimate |
