Keywords
wrist arthrodesis - wrist fusion - plate - consolidation rate - complications
Introduction
Total wrist arthrodesis using a dorsal plate is a safe and practical alternative for
patients with several pathological conditions that evolve with wrist arthrosis.[1] However, its indication is not limited to this situation, and it may also be indicated,
for example, to increase the flexion force of the fingers in a patient with brachial
plexus injury submitted to free functional motor transfer surgery.[2] Total wrist arthrodesis is often considered the last therapeutic option for degenerative
or post-traumatic painful arthrosis of the wrist[3] because although it can relieve pain, it eliminates flexion-extension movements
and ulnar-radial deviation of the wrist.[4]
Fixation with dorsal plates in total wrist arthrodesis results in high healing rates
(96 to 98%) when compared with older techniques such as bone graft without an implant,
intramedullary pinning with Steinmann pin, and trans-articular pinning with Kirschner
wires, which attain much higher nonunion rates (19%).[5]
[6]
[7]
[8]
[9] Over time, specific locked intramedullary implants were developed in order to reduce
the rate of complications.[10]
Over the years, some studies have shown a high rate of complications associated with
the use of dorsal plates such as plate fractures, and a high potential for soft tissue
irritation, including symptomatic friction, tenosynovitis, and extensor tendon adherence,
despite the high healing rate.[11]
[12]
[13] A more recent systematic review (2018) found a complication rate of 6.1% for total
wrist arthrodesis.[14]
In this context, a low profile and variable angle locked plate (TriLock APTUS 2.5
wrist arthrodesis plate, Medartis AG, Basel, Switzerland) was developed for total
wrist arthrodesis. It has rounded edges and an anatomically curved “low profile” minimizing
the potential for soft tissue irritation or tendon friction. Due to the lack of availability
of implants in our hospital for arthroplasty (which presents promising results and
allows the maintenance of a greater range of motion in the wrist),[15]
[16] arthrodesis with a low profile plate is our main option for treating wrist arthrosis.
Therefore, the present study was carried out with the aim of identifying the factors
that influence the healing of total wrist arthrodesis using the Aptus ® 2.5 Trilock
Wrist Fusion Plate (Medartis AG, Basel, Switzerland) and the frequency of complications.
Material and Methods
All participants in this research were studied according to the Research Standards
Involving Human Beings (Res. CNS 466/12) of the National Health Council after approval
of the project by the Ethics and Research Committee of the Institution (CAAE: 98775418.9.0000.5273).
We undertook a review of patients' medical records to collect data in a descriptive,
observational, retrospective study. Patients submitted to total wrist arthrodesis
procedure in a single hospital from April 2015 to November 2021 using a long or short
(with or without fusion of the joint between carpal and third metacarpal) Aptus ®
2.5 Trilock Wrist Fusion Plate (Medartis AG, Basel, Switzerland) were included in
the study. The surgeons of this hospital normally choose the long plate for narrower
bones and rheumatoid arthritis patients. ([Figures 1] and [2]).
Fig. 1 Radiographs of wrist arthrodesis with fusion of the joint between carpal and third
metacarpal (long plate).
Fig. 2 Radiographs of wrist arthrodesis without fusion of the joint between carpal and third
metacarpal (short plate).
All cases with incomplete medical records, with post-operative follow-up of less than
1 year, use of another type of implant, or the absence of postoperative imaging records
were excluded from the study.
To evaluate the healing and complications, mDicom Viewer software was used to visualize the radiographs and computed tomography scans of the wrists.
Pre- and postoperative radiographs were obtained for follow-up and confirmation of
healing with further tomographic studies being undertaken when consolidation was not
certain in the radiographs. Arthrodesis that demonstrated bone bridging of three cortices
on orthogonal radiographs or the formation of a single bone block on tomographic images
were considered healed.
Data on age, gender, smoking, etiology and time of pathology, date of surgery, comorbidities,
use of bone graft, time for healing, complications, and need for review were collected
using a previously prepared form.
The results were presented using descriptive measures, such as absolute and relative
frequencies; and by means of numerical summary measures, such as minimum, maximum,
means, and respective standard deviations. For data analysis, a comparison of categorical
variables was performed using the chi-square test or Fischer's Exact Test (if applicable)
by means of comparisons between proportions.
For all statistical analyses, a p-value of ≤ 0.05 was considered statistically significant.
All data analyses were performed using the statistical software SPSS 23.0 (Statistical Package for Science - Chicago, IL, USA 2008).
Results
The present study consisted of a sample of 82 research participants with 85 cases
of arthrodesis (since 3 individuals were operated on bilaterally). The surgical indications
were: 30 cases of arthrosis caused by distal radius malunion, 17 cases of rheumatoid
arthritis, 17 cases of scapholunate advanced collapse (SLAC), 12 cases of scaphoid
nonunion advanced collapse (SNAC), 6 cases of Kienbock disease, 1 case of Madelung
deformity, 1 case of spasticity in a patient with cerebral palsy and 1 sequela of
a snake bite.
Considering the general characteristics of the sample, most participants were male
(69.4%), non-smokers (80%), with a mean age of 50.7 years. Fifty-point-six percent
of the individuals did not present comorbidities; 49.4% had short plate implantation
and 63.5% of the procedures had bone grafting. The follow-up time ranged from 1 to
7 years, with a mean of 4.6 years; and the mean time of healing was 4.6 months, ranging
from 2 to 12 months ([Table 1]).
Table 1
|
VARIABLES
|
n (%)
|
|
Sex
|
|
|
Female
|
26 (30.6)
|
|
Male
|
59 (69.4)
|
|
Smoking
|
|
|
No
|
68 (80.0)
|
|
Yes
|
17 (20.0)
|
|
Comorbidities
|
|
|
No
|
43 (50.6)
|
|
Yes
|
42 (49.4)
|
|
Plate type
|
|
|
Short
|
42 (49.4)
|
|
Long
|
43 (50.6)
|
|
Bone graft
|
|
|
No
|
31 (36.5)
|
|
Yes
|
54 (63,5)
|
|
Mean (SD)
Maximum Minimum
|
|
Age (years)
|
50.7 (11.3)
23 - 81
|
|
Healing time (months)
|
4.6 (2.1)
2 - 12
|
|
Follow-up time (years)
|
4.6 (1.6)
1 - 7
|
All patients presented significant pain and limitation of movements in the preoperative
period and the mean time between the onset of the pathology until the time of surgery
was 8.1 years (SD:6.01).
In three cases patients had pain in the ulnar side of the wrist following surgery
and underwent a further operation using the Darrach procedure an average of 10 months
after the first procedure. There was one case of surgical site infection which was
resolved with mechanosurgical lavage and administration of intravenous antibiotic
therapy. One patient was submitted to the removal of the plate 12 months after the
procedure due to discomfort generated by the plate.
Two patients with rheumatoid arthritis suffered periprosthetic fracture 10 months
after the procedure, with arthrodesis already consolidated. In one, the solution was
the proximal slipping of the plate ([Figures 3] and [4]) and the other was treated conservatively with closed reduction, and immobilization
and consolidation was observed after 3 months in both cases. In another case, the
loosening of two distal screws was observed in the metacarpal 1 month after the procedure,
being quickly resolved with a screw change and healing in 4 months.
Fig. 3 Peri-implant fracture.
Fig. 4 Postoperative radiographs of the above case.
In one patient (SNAC wrist) submitted to arthrodesis with a short plate, loosening
of the screws in the carpal at 2 months was observed, and was resolved with a replacement
with a long plate, with healing in 8 months ([Figures 5] and [6]). The complication rate, therefore, was 10,5% (9 cases).
Fig. 5 Radiographs after loosening of screws.
Fig. 6 Postoperative radiographs of the above case.
After analyses of the correlations between the mean time of consolidation in relation
to gender, comorbidities, smoking, the etiology of the arthrosis, type of plate, and
the use of grafts, only the variable smoking showed a statistically significant difference,
with a mean time of healing in smokers of 5.8 months and in non-smokers of 4.2 months
(p = 0.03). The other variables analyzed did not present any statistical significance,
although the mean time of healing in procedures with long plates was slightly shorter
than with the use of short plates ([Table 2]).
Table 2
|
VARIABLES
|
Consolidation Time (months)
Mean (SD)
|
p value[a]
|
|
Sex
|
|
|
|
Female (n = 26)
|
4.5 (1.8)
|
0.89
|
|
Male (n = 59)
|
4.6 (2.2)
|
|
|
Smoking
|
|
|
|
No (n = 68)
|
4.2 (1.7)
|
0.03
|
|
Yes (n = 17)
|
5.8 (2.9)
|
|
|
Comorbidities
|
|
|
|
No (n = 43)
|
4.6 (2.2)
|
0.90
|
|
Yes (n = 42)
|
4.5 (2.0)
|
|
|
Plate type
|
|
|
|
Short (n = 42)
|
4.9 (2.4)
|
0.18
|
|
Long (n = 43)
|
4.3 (1.7)
|
|
|
Graft
|
|
|
|
No (n = 31)
|
4.6 (2.4)
|
0.93
|
|
Yes (n = 54)
|
4.6 (1.9)
|
|
|
Rheumatoid arthritis
|
|
|
|
No (n = 69)
|
4.6 (2.2)
|
0.49
|
|
Yes (n = 16)
|
4.2 (1.4)
|
|
Discussion
In the 1990s, studies began to report healing rates close to 100% for wrist arthrodesis,
most of which emphasized the importance of autologous bone grafting and the use of
stable internal fixation methods.[17]
[18]
[19]
[20] In our sample, there was also 100% healing, but there was no difference in the time
of consolidation or the frequency of complications associated with the use of grafts.
However, there were some complications related to implant design, such as irritation
or synovitis, and in one case removal of the implant was required.[21]
[22] In our sample, the complication rate was 10.5% (9 cases), the vast majority of which
were unrelated to the implant (three due to pain in the ulnar corner of the wrist,
one infection, and two peri-implant fracture after trauma), only one case of discomfort
generated by the plate and two cases of the loosening of screws in the early postoperative
phase, all resolved after a further intervention. We believe that the use of low-profile
locking plates contributed to these good results.
In respect of the different types of plates used (with or without fusion of the carpometacarpal
joint), recent studies present comparable rates in respect of healing and complications,[23] pain, grip strength and DASH functional scores (Disabilities of the Arm, Shoulder,
and Hand), with a greater range of motion in the carpometacarpal (CMC) with the use
of short plates, improving hand kinematics.[24] Furthermore, we did not find any differences in healing rates or complications according
to the type of plate used. There was a non-statistically significant longer mean time
for healing of long plate surgeries (4.9 months) when compared to short plate surgeries
(4.3 months).
Previous studies have demonstrated the impact of smoking on hand surgery suggesting
that it is associated with complications related to surgical wound delayed consolidation
after osteosynthesis of the distal radius,[25]
[26] and an increase in the rate of nonunion after arthrodesis of the hand and wrist.[27] In our sample, we observed an increase in the meantime for healing in smokers (5.8
months) compared to nonsmokers (4.2 months), a factor that was statistically significant,
although the healing rate did not change.
Our study presents some limitations such as its retrospective nature, which limits
the information to that obtained from the analysis of medical records and radiographs
in the review consultations, and the lack of clinical data such as muscle grip strength
and functional scores such as DASH in pre-and postoperative evaluations. However,
it is a very large and uniform sample, because all the patients received the same
implant in the same hospital in a period of only 6 years. In addition, the sample
comprised patients with diverse causes of wrist arthrosis.
In conclusion, our result show that wrist arthrodesis performed with the Aptus ® 2.5
Trilock Wrist Fusion Plate (Medartis AG, Basel, Switzerland) in our hospital had a
100% consolidation rate with a very low rate of implant-related complications and
without differences related to graft placement, carpalcarpal joint fusion, comorbidities,
or the demographic data of the patients. In addition, it is important to note that
smoking increased the healing time but did not lead to nonunion.
