Keywords
distal radius - bone plates - external fixators
Introduction
Distal radius fractures correspond to 12% of fractures in adults, constituting a major
cause of morbidity.[1] In younger populations, these injuries are severe comminuted fractures resulting
from high-energy trauma; in the elderly population, they are caused by low-energy
trauma.[2] If not properly treated, these fractures result in chronic pain, motion limitation
and functional impairment,[3] with a great impact on the patient's quality of life and burdening the public healthcare
system, since most of these subjects are young patients who are unable to work.[2]
Despite the great prevalence and social consequences of these injuries, there is still
no consensus as to the best treatment due to the great possibility of distal radial
fracture profiles.[4] The best therapeutic method must consider the fracture pattern (classification,
bone quality), patient profile (age, daily activities), additional injuries (ligament
or bone lesions) and the surgeon's experience with the materials.[5]
Distal radius fractures can be conservatively or surgically treated depending on the
aforementioned factors.[6] No treatment is exempt from complications, and they must be customized for each
individual patient. The surgical treatment can be beneficial in fractures meeting
the Lafontaine criteria after closed reduction.[7] The options of surgical treatment include percutaneous fixation with Kirschner wires,
volar or dorsal plates, and external fixators[.8] The most widespread methods are Kirschner wires and volar plates due to the easy
access to these materials. However, in highly-comminuted fractures from high-energy
trauma or those affecting osteoporotic bones, these methods may be unsuccessful.[1]
[3] Since these joint fractures are difficult to stabilize, new fixation forms are required.
Other options include external fixators and bridge plates associated with Kirschner
wires[9] External fixators are promptly placed, with lower cutaneous aggression, but they
are esthetically worse for patients and related to a higher risk of infection at their
path.[10] Bridge plates are more aggressive to the soft tissues due to the incision, but they
can result in an improved fracture reduction.[11]
The present study compared the postoperative outcomes of comminuted distal radius
fractures classified as 23C2 or 23C3 according to AO Classification System surgically
treated with an external fixator and Kirschner wires or with a dorsal bridge plate.
Materials and Methods
Ethics
The present was an observational, analytical study approved by the Ethics in Research
Committee of Hospital Municipal São José (Joinville, Santa Catarina, Brazil) under
opinion number 2.439.743.
Participants
In total, 43 patients presenting intra-articular distal radius fracture with AO classification
23C2 or C3 and followed-up for at least 1 year after surgery in an outpatient facility
were selected. Among them, 18 patients were treated with an external fixator, and
25 received a bridge plate, associated with Kirschner wires if required. The sample
size was based on previously-published studies comparing surgical techniques for distal
radius fractures using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire.[12]
[13]
The patients were recruited from December 2017 to May 2018 during outpatient return
visits at Hospital Municipal São José, in which the surgical treatment was performed,
always by the same hand surgeon, who is the chief physician. Patients with associated
fractures in the same limb, open distal radial fractures, previous deformities and/or
those requiring care at an intensive care unit were excluded from the study.
Surgical Techniques
In patients treated with an external fixator, Schanz pins were placed under fluoroscopy
at the second metacarpal bone diaphysis and the radial diaphysis; the fracture was
reduced and fixed using the Colles external wrist fixator. If required, Kirschner
wires were associated to maintain the reduction and add stability ([Figure 1]). At the postoperative follow-up of six to eight weeks, the external fixator and
the Kirschner wires were removed under local anesthesia at the Schanz pins, according
to the radiographic evaluation. Subsequently, the patient was referred for physical
therapy and rehabilitation.
Fig. 1 Postoperative radiograph of a patient with an external fixator.
The dorsal bridge plate technique was initially described as a form of distraction
for more complex type-C3 fractures; here, however, it was used as an alternative in
type-C2 fractures, which are more common in hospital care.
In patients treated with dorsal bridge plate and screws, 3 incisions were made: an
incision of approximately 2 cm at the region of the third metacarpal diaphysis, an
incision at the third extensor tunnel, at the level of the Lister tubercle, to isolate
the long extensor tendon of the thumb, and 1 incision at the radial diaphysis ([Figure 2]). Then, the plate was placed retrogradely.
Fig. 2 Intraoperative image of the bridge plate technique.
A dynamic compression plate (DCP) was placed juxta-osseously, moving the long extensor
tendon of the thumb at the third tunnel through an access of approximately 3 cm in
the Lister tubercle. The plate was passed below the extensor tunnels, and an access
was made to isolate the long extensor tendon of the thumb and to make sure that the
plate was below the tendons. Fixation was performed with two distal screws, followed
by fracture reduction and fixation with two proximal screws. A synthesis with Kirschner
wires was also performed if required ([Figure 3]).
Fig. 3 Postoperative radiograph of a patient with a dorsal bridge plate.
All patients received an intraoperative antibiotic agent (cefazolin), in addition
to an oral prophylactic antibiotic agent (cephalexin) for 10 days.
The first return visit was standardized for two weeks after surgery for suture removal
and general education. Six weeks after the procedure, finger mobility was accessed,
and the external fixator and Kirschner wires were removed. Twelve weeks after surgery,
finger mobility after the removal of the external fixator was accessed; in addition,
the synthesis material was removed at the operating room under anesthesia, and the
joint was manipulated. After the removal of the synthesis material, patients from
both groups were referred to physical therapy and rehabilitation, returning for visits
every 12 weeks to assess mobility until completing 1 year of outpatient follow-up.
Evaluated Variables
Outcome variables were collected up to one year after surgery during the outpatient
follow-up. The presence of superficial or deep infections and the incidence of reflex
sympathetic neuropathy were determined through the analysis of the medical records,
as the diagnosis is clinical in both situations.
The visual analog scale (VAS) was used to assess the postoperative pain.
The DASH questionnaire was used for the functional assessment of the patients, and
it consists of 30 questions related to limitations in daily living activities.[14] The questionnaire was always applied by the same evaluator. The questions were read
and explained before they were answered by the patient.
Radiographic measurements of distal radial angles were performed with a goniometer
on anteroposterior (AP) and lateral radiographs using the appropriate technique.
Ranges of motion were determined at a physical examination using a goniometer in flexion
(normal: 70° to 80°), extension (normal: 60° to 70°), maximum pronation (normal: 0°
to 80°), maximum supination (normal: 0° to 90°), radial deviation (normal: 20°) and
ulnar deviation (normal: 45°).[15]
Grip strength was evaluated using a calibrated digital dynamometer, always by the
same operator; values from both hands were determined and considered normal, decreased,
or increased compared to the contralateral side.
Statistical Analysis
Data were tabulated in an Excel (Microsoft Corp. Redmond, WA, US) spreadsheet and
submitted to statistical analysis using the Statistical Package for the Social Sciences
(SPSS, IBM Corp., Armonk, NY, EUA), version 20.0. The frequency and distribution of
the variables were determined. Nominal variables were related to surgical techniques
using the chi-squared test. Numerical variables were related to surgical techniques
through a non-parametric Mann-Whitney test.
Results
From the 43 patients evaluated, the mean age was 54.4 years old, and 25 patients (58.1%)
of them were female. The most prevalent trauma mechanism was a fall from the own height
(51.2%). In 22 patients (51.2%), the fracture occurred on the right side; 34 patients
(79.1%) were right-handed ([Table 1]).
Table 1
|
Characteristics
|
N (%)
|
|
Gender
|
|
|
|
Male
|
18 (41.9)
|
|
Female
|
25 (58.1)
|
|
Age
|
|
|
|
20–35
|
9 (20.9)
|
|
36–45
|
5 (11.6)
|
|
46–60
|
9 (20.9)
|
|
> 61
|
20 (46.5)
|
|
Surgical technique
|
|
|
|
Bridge plate
|
25 (58.2)
|
|
External fixator
|
18 (41.8)
|
|
Trauma mechanism
|
|
|
|
Fall at the own height
|
22 (51.2)
|
|
Fall from height
|
14 (31.7)
|
|
Traffic accident
|
7 (17.1)
|
|
Fractured side
|
|
|
|
Right
|
22 (51.2)
|
|
Left
|
21 (48.8)
|
|
Dominant side
|
|
|
|
Right
|
34 (79.1)
|
|
Left
|
9 (20.9)
|
Regarding postoperative infection, there was one case in the bridge plate group and
two cases in the external fixator group, with no significant difference in incidences
from both techniques (p = 0.379). Reflex sympathetic neuropathy occurred in two patients treated with bridge
plates and in one patient receiving an external fixator; once again, there was also
no statistically significant difference between both groups (p = 0.738). In total, 15 patients operated with bridge plate and 6 treated with an
external fixator showed decreased grip strength, with a statistically significant
difference between the 2 surgical techniques (p = 0.041) ([Table 2]).
Table 2
|
Surgical techniques
|
|
Bridge plate
|
External fixator
|
p-value
|
|
Postoperative infection
|
Yes
|
1
|
2
|
0.379
|
|
No
|
24
|
16
|
|
Reflex sympathetic neuropathy
|
Yes
|
2
|
1
|
0.738
|
|
No
|
23
|
17
|
|
Grip strength
|
Normal
|
10
|
12
|
0.041
|
|
Decreased
|
15
|
6
|
According to the VAS, both techniques were associated with the same level of pain,
with no statistically significant difference between them. The mean DASH score for
the patients operated with a bridge plate was 39.05, and it was 36.36 for those operated
with an external fixator, with no statistically significant difference between them
(p = 0.569). At the radiographic assessment, there were no statistically significant
differences between the two surgical techniques in any of the measurements performed.
Similarly, there were no statistically significant differences in the ranges of motion
for extension, flexion, pronation, and radial deviation. In supination, the mean values
were 41.82 and 59.29 for the bridge plate and the external fixator respectively, with
a statistically significant difference between them (p = 0.012). Ulnar deviation presented a statistically significant difference between
both surgical techniques (p = 0.0049), with 7.73 for the bridge plate, and 13.57 for the external fixator ([Table 3]).
Table 3
|
Bridge plate
|
External fixator
|
p-value
|
|
Pain scale
|
3.68 ± 2.61
|
4.64 ± 2.43
|
0.172
|
|
DASH
|
39.05 ± 13.75
|
36.36 ± 12.03
|
0.569
|
|
Radiographic measurements
|
|
|
|
|
Radial height
|
8.14 ± 2.27
|
9.29 ± 2.19
|
0.069
|
|
Radial angle
|
15.91 ± 4.45
|
17.86 ± 3.18
|
0.217
|
|
Volar deviation
|
3.55 ± 4.00
|
4.21 ± 3.66
|
0.329
|
|
Range of motion (ROM)
|
|
|
|
|
ROM – extension
|
40.45 ± 16.75
|
45.71 ± 14.39
|
0.667
|
|
ROM – flexion
|
51.14 ± 16.68
|
52.14 ± 18.47
|
0.438
|
|
ROM – pronation
|
43.18 ± 18.09
|
58.21 ± 17.71
|
0.062
|
|
ROM – supination
|
41.82 ± 18.67
|
59.29 ± 20.17
|
0.012
|
|
ROM – ulnar deviation
|
7.73 ± 7.02
|
13.57 ± 8.41
|
0.0049
|
|
ROM – radial deviation
|
7.73 ± 6.31
|
12.86 ± 6.41
|
0.066
|
Discussion
To our current knowledge, few studies compared the treatment of comminuted fractures
with external fixators and bridge plates. These fractures are very prevalent and difficult
to manage, and there is no consensus on the best surgical technique to treat them.
As such, the present study was carried out to show the outcomes with the use of materials
that are easily accessible through the Brazilian Unified Health System (Sistema Único
de Saúde, SUS, in Portuguese) and may improve the lives of the patients.
The dorsal bridge plate technique is indicated for deviated comminuted joint fractures
with diminutive fragments that cannot be fixed using a volar plate.[16] Some authors advocate dorsal plates due to ligamentotaxis, which helps reduce fractures
and spares soft tissues. Since there is no friction between tendons of the extensors
and the plate, this technique favors finger mobility, and it is indicated in osteopenic
bones, comminuted fractures, and polytraumas.[17] However, the dorsal plate may result in loss of wrist mobility, and it requires
removal and reduces the fracture in only one plane.[17] In addition to the 3.5-mm DCP plate, there are semi-tubular plates in a single column
for the radius or double column. When the fracture line is more proximal, 2.4-mm and
3.5-mm reconstruction plates may be used, which are more available at the SUS. Other
plate types have been developed for this surgical technique, such as low-profile interlocked
plates, which can be used in the second or third metacarpal bones. Wrist arthrodesis
plates can also be employed to fix distal radius fractures, enabling the placement
of larger screws to add stability. Similar to arthrodesis plates, more specific devices
have recently emerged to treat these fractures through distraction; these are the
spanning plates, which are shaped to facilitate the passage through extensor tendons
and have fewer central holes, providing increased stiffness.[16]
[18]
Wrist transarticular external fixators were introduced in 1970,[17] and are increasingly used. As an advantage, these fixators are minimally-invasive,
sparing the retinaculum and the tendons. In addition, this is an easy and quick technique
for polytrauma patients.[19]
When comparing the two surgical techniques, in general terms, we did not observe statistically
significant differences, similarly to Saving et al.,[20] who evaluated the postoperative outcomes of external fixators and volar plates in
a three-year follow-up period.
As complications, there were three cases of postoperative infection, two in patients
treated with external fixators and one in a subject receiving a bridge plate. One
of the cases of infection with an external fixator was superficial, and it was treated
with an oral antibiotic agent, whereas the other required surgical debridement and
fixator realignment. The bridge plate infection required surgical debridement and
intravenous antibiotic therapy. Cui et al.[21] compared the use of internal versus external synthesis in patients with AOC3 distal
radial fracture, and they observed a higher rate of infection when the external synthesis
was performed. Abramo et al.[22] evaluated 50 patients with unstable distal radius fractures submitted to open reduction
and internal fixation or closed reduction and external fixation, and they observed
equivalent rates of superficial and deep infections in both techniques, corroborating
our findings. In that study,[22] the main postoperative complication was hyperesthesia at the sensitive path of the
radial nerve. Kreder et al.[23] assessed 179 patients with distal radial fractures treated with percutaneous fixation
or internal fixation, using external fixators and plates. Infection was the most common
postoperative complication; superficial infections were more common in indirect reduction
with percutaneous fixation, but the incidence of deep infections was similar in both
groups. In a meta-analysis study[18] comparing external fixators and bridge plates, the incidence of infection and reflex
sympathetic dystrophy was lower in patients treated with bridge plates, but the cases
of dystrophy did not require additional surgical treatment.
Reflex sympathetic neuropathy occurred in 2 patients treated with plates and 1 patient
receiving an external fixator, corresponding to almost 7% of the total of patients;
all of these subjects were female. Xu et al.[24] compared the treatment of type-C fractures according to the AO classification with
external fixation and plates and did not observe any case of reflex sympathetic dystrophy.
Arora et al.[25] evaluated the incidence of reflex sympathetic neuropathy in patients older than
65 years of age with distal radial fractures, including 36 subjects who underwent
surgery and 37 individuals who were conservatively treated. Two surgical patients
and five who were treated conservatively developed the syndrome. All patients improved
their condition with analgesia and physical therapy. Xavier et al.[26] evaluated patients treated with blocked volar plates for distal radius fractures,
and they observed an incidence of 1.5% of reflex sympathetic dystrophy, illustrating
that even more modern materials may cause this complication.
Grip strength increased when external fixators were used. This is probably due to
the earlier finger mobility provided by the lack of plastered immobilization, with
sustained moving during the immediate postoperative period; in addition, the placement
of the dorsal plate requires lesser muscle manipulation during surgery. This finding
is in line with the observation by Schønnemann et al.[27] that internal synthesis materials have better outcomes when external fixation is
compared with intramedullary fixation. Aita et al.[28] compared the distal radial fixation with plates, nails and external fixators, and
they observed that, at the third postoperative week, the grip strength was lower in
the subjects treated with external fixators compared to other techniques; however,
after one year, the grip strength was similar in the patients from the three groups.
McQueen and Caspers[29] described the main complications of distal radius fractures, such as pain, stiffness,
deformity, and loss of grip strength. These findings remain true today, despite the
major advances in surgical techniques.
In the present study, we observed that, regardless of the treatment, postoperative
pain after the removal of the synthesis material and physical therapy was similar
in both groups. This outcome may be attributed to the reduction in fractures with
similar radiographic features, because a better reduction of the fracture results
in improved range of motion and less pain.[30] Aita et al.[28] compared locked volar plates, intramedullary nails and external fixators for the
treatment of distal radius fractures, and they found a lower rate of pain in patients
with internal synthesis material compared to those receiving external fixators after
the third week.
The DASH scores were similar for both surgical techniques. These data were also obtained
by Zenke et al.,[31] who found no significant difference when comparing these techniques. Xavier et al.[26] observed a correlation between reduced extension, flexion and grip strength with
worse DASH scores, with an average DASH score of 10 for young people and of 21 for
elderly patients.
The radiographic evaluation showed that we achieved a similarly acceptable fracture
reduction with both techniques. A meta-analysis by Cui et al.[21] showed that several papers comparing different techniques also managed to reduce
fractures within the recommended parameters. The only difference found by Xu et al.[24] was regarding radial inclination throughout years of evaluation, with no alterations
in the range of motion of the patients.
In the present study, the ranges of motion resulting from both techniques were similar,
except for supination and ulnar deviation, which were improved with the use of external
fixators. Despite this difference, both techniques reached functional ranges of motion.
Xavier et al.[26] also found no difference the range of motion of the patients. Kreder et al.[23] did not observe differences between different groups regarding postoperative mobility.
Evaluating 33 patients older than 60 years of age with osteoporotic bones and C2 or
C3 fractures who were treated using the dorsal bridge plate technique, Richard et
al.[32] obtained good results for consolidation and range of motion.
Lewis et al.[33] assessed the incidence of complications in the fixation of second or third metacarpal
bones in cadavers. The authors concluded that the fixation of the third metacarpal
bone had a greater chance of injury to the long extensor tendon of the thumb and,
that the flexion-extension of the wrist was a bad indicator.
Our findings are particularly important for the progression of the fixation of distal
radius fractures in patients with severe injuries who need to return to their daily
and professional activities as soon as possible. Both operative techniques are easy
to perform for orthopedic surgeons, and they require cheap materials that are promptly
available at public services.
The reduced number of patients evaluated and their highly variable age, indicating
different bone qualities, can be considered limitations for this study. We suggest
that future studies include a higher number of subjects, stratified by age, and the
inclusion of other fixation methods available, such as radial intramedullary nail
and distal radial locked plate.
Conclusion
Both techniques proved to be effective in the treatment of complex distal radius fractures,
with a low rate of postoperative complications, satisfactory functional outcomes,
and no superiority of one over the other.
