Keywords
clavicle - fractures, bone - treatment outcome - minimally invasive surgical procedures
Introduction
Clavicle fractures account for 2.6 to 5% of all fractures in adults;[1]
[2]
[3] ∼ 80 to 85% of these injuries affect the middle third of the bone.[1]
[2] Complex or comminuted midshaft clavicle fractures are commonly caused by high-energy
accidents, direct trauma or axial compression.[3]
[4] Clavicular biomechanics differ from that of long bones and the behavior of clavicle
comminuted fractures is poorly studied.[5] According to the literature, the conservative treatment of these fractures is associated
with higher pseudoarthrosis rates.[2]
[6]
[7] Other studies argue that the surgical treatment leads to improved functional outcomes
when compared to the nonsurgical treatment.[6]
[7]
[8]
[9] Most Brazilian orthopedists indicate osteosynthesis for deviated and/or comminuted
shaft fractures.[10]
The most widely used osteosynthesis method for deviated clavicular shaft fractures
is open reduction and internal fixation (ORIF) with plate and screws.[5]
[9] However, since comminuted fractures require an extensive access to the fracture
site, this approach may be associated with high rates of complications, including
hypertrophic, painful scars,[4] infection,[11] pseudoarthrosis,[12] implant failure and refracture after implant removal.[13] As advantages, the minimally invasive osteosynthesis (MIO) technique with plates
preserves the blood supply at the fracture site[14] and can decrease these complications. Minimally invasive osteosynthesis is commonly
used in complex long bone fractures in lower limbs,[15] and has proven applicability in diaphyseal fractures of the upper limbs.[16]
Some authors have described their MIO techniques and outcomes in clavicle comminuted
fractures.[17]
[18] The published studies use implant materials that are not easily accessible to the
Brazilian population through the Brazilian Unified Health System (SUS, in the Portuguese
acronym). There are no studies in the Brazilian literature regarding the MIO technique
with plates to treat such fractures. The present study aims to evaluate clinically
and radiographically a group of patients with comminuted midshaft clavicle fracture
who were surgically treated using the MIO technique and a 3.5 mm reconstruction plate
in the upper position.
Methodology
Longitudinal, observational study, with a retrospective initial survey of patients
with comminuted midshaft clavicle fracture who were surgically treated using the MIO
technique with plate in the upper position by one of the authors from January 2014
to May 2017 at the university hospital from our institution. The sample size corresponds
to the number of patients who were surgically treated in this period and attended
the evaluation. The study included patients > 16 years old with comminuted midshaft
clavicle fracture type 2B2 according to the Robinson classification[9] who were surgically treated within 21 days after the trauma and were followed-up
for a minimum period of 12 months. Patients with open fractures or associated vascular
and nerve injuries, fractures extending to joints, fractures and/or discomfort concomitant
with shoulder girdle trauma, concurrent fractures in other parts of the upper limb
(arm, forearm, wrist and hand), history of previous clavicular fractures or shoulder
girdle trauma, pathological fractures, and metabolic and/or congenital diseases were
excluded. The final sample consisted of 32 patients. Patients eligible for the study
for meeting inclusion and exclusion criteria were contacted for an interview, in which
the study was explained and the informed consent form (ICF) of the study was presented.
Subjects who agreed in participating in the study were prospectively submitted to
a clinical evaluation, including the Disability of Arm, Shoulder and Hand (DASH) questionnaire,[19] and radiological tests. Functional evaluation included the DASH questionnaire and
a physical examination (passive range of motion of the shoulder, subacromial, rotator
cuff and acromioclavicular impingement tests, thoracic scapular dyskinesia and force
during active elevation measured with a manual dynamometer [Science SuplySolutions
# U40812 [Science Supply Solutions, LLC, Bensenville, Illinois, United States of America],
graduation 1 kg/10 N]) performed by an examiner not as involved in the surgical procedures
as the main surgeon. At the postoperative period, a digital radiographic evaluation
of the clavicles was performed in anteroposterior (AP) and modified craniocaudal views
for verification purposes; a posteroanterior (PA) chest radiograph was taken to measure
the final length of the clavicle according to the criteria by Smekal et al.[20]. In addition, medical records were analyzed on outcomes of the surgical procedure,
such as consolidation time, delayed consolidation, pseudoarthrosis, infection, implant
loosening, synthesis material failure, residual pain and range of motion.
Surgical technique (adapted from Jung et al.[18]): patient in the beach chair position; the procedure was aided by radioscopy in
frontal and modified craniocaudal views of the clavicle with an approximate inclination
of 70° ([Figure 1]). A fracture reduction maneuver (the Kibler maneuver) was performed; the surgeon
put the ipsilateral arm to a posterior, slightly superior position, with lateral rotation
of the shoulder, approximating the scapula to the rib cage with lateral, superior
rotation and posterior scapular inclination (a position mimicking retraction), leading
to the indirect clavicle fracture reduction. Using radioscopy, the clavicular length
and shape were determined to choose the implant size (3.5-mm, unlocked reconstruction
plate). Next, the medial and lateral ends of the clavicle were palpated to locate
the sternal and acromial borders, respectively. A transverse incision 1 cm lateral
to the sternal border, with ∼ 1.5 cm, was performed on the upper surface, with deep
plane dissection up to the bone bed (upper clavicle surface). In the lateral region,
1 cm medial from the acromial border, a second incision was made, with the same size,
direction and depth, up to the upper clavicle surface. Another bed was prepared at
the upper region of the clavicle, from medial to lateral, to pass the implant to an
upper position with instruments for blunt dissection ([Figure 2]). The plate was modeled during surgery ([Figure 3]), with a medial anterior convexity and a lateral posterior convexity, both at the
level of the third most lateral and medial plate holes, following the clavicular shape
determined at radioscopy. The plate was slipped in the supraclavicular tunnel from
medial to lateral, with the scapula kept in a retracted position. Provisional fixation
was performed with 2.5-mm Kirchner wires (for length evaluation under radioscopy),
and the plate was fixated with 3 bicortical screws on each side, alternately, starting
from the medial side. Reduction and final plate and screws positioning were verified
([Figure 4]). Wounds were irrigated with 0.9% saline solution; deep layers were closed with
3.0 mononylon sutures followed by 2.0 intradermal sutures.
Fig. 1 Radioscopy positioning for superior and anterior views.
Fig. 2 Medial and lateral incisions.
Fig. 3 Plate modeling.
Fig. 4 Before and after fixation with the minimally invasive osteosynthesis (MIO) technique.
After surgery, the limb was kept in a sling for 6 weeks, and full elbow, wrist and
hand movements were oriented. Elevation, abduction > 30° and shoulder rotations were
discouraged. After 8 weeks, full active shoulder movements were allowed. Return to
activities with load and playing sports were allowed after detecting signs of fracture
consolidation on control radiographs.
The patients were followed-up on an outpatient basis, with initial visits in 15 and
30 days and, next, monthly visits until the detection of bone consolidation on control
radiographs. Bone union was determined by signs of bone callus on both AP and craniocaudal
radiographs, and absence of mobility on diaphyseal palpation.
For statistical analysis, descriptive data was expressed as frequency, mean and standard
deviation (SD) tables. The Fisher exact test analyzed associations between categorical
variables. Paired t-tests compared the operated and nonoperated sides for continuous
numerical variables. Error normality was analyzed by box plot, quantile-quantile graph
and the Shapiro-Wilk test. The analyses were carried out in R* software (R Foundation,
Vienna, Austria) considering a significance level of 5%. The present manuscript was
written according to the Strengthening the Reporting of Observational Studies in Epidemiology
(STROBE) Statement guidelines for observational studies (Annex 1) and was approved by the institutional ethics committee under the number CAAE 66877517.5.0000.5133.
Results
The sample consisted of 32 patients, with 31 males and mean age of 41 years old (range,
19 to 61 years old). The median follow-up period was of 21 months (range, 12 to 45
months). The fractures were caused mainly by high-energy trauma (motorcycle and car
accidents). The average time until the procedure was 9 days. Demographic data of the
patients are presented in [Table 1].
Table 1
Variable
|
Frequency (%)
|
Gender
|
|
Female
|
1 (3.1)
|
Male
|
31 (96.9)
|
Trauma type
|
|
Motorcycle accident
|
14 (43.8)
|
Fall to the ground
|
9 (28.1)
|
Car accident
|
4 (12.5)
|
Others
|
5 (15.6)
|
Side
|
|
Right
|
10 (31.3)
|
Left
|
22 (68.8)
|
Dominance
|
|
Right
|
31 (96.9)
|
Left
|
1 (3.1)
|
Categorical variables obtained during physical examinations revealed no differences
between the operated and nonoperated sides. These variables were not associated to
continuous numerical variables from the physical examination or functional scores.
The operated side had statistically significant (p <0.05) lower mean passive elevation
and higher mean clavicle length compared with the nonoperated side ([Table 2]). There was no statistically significant difference regarding the presence or not
of scapular dyskinesia when comparing the operated and nonoperated sides.
Table 2
Variable
|
Total Mean (SD)
|
Side
|
p-value
|
Operated Mean (SD)
|
Nonoperated Mean (SD)
|
Elevation (degrees)
|
157.67 (7.89)
|
155.67 (10.73))
|
159.67 (1.83)
|
0.0497[a]
|
Lateral rotation (degrees)
|
83.83 (11.77)
|
83.17 (12.49)
|
84.50 (11.17)
|
0.4029
|
Force (Kgf)
|
11.43 (2.51)
|
11.23 (2.96)
|
11.63 (1.99)
|
0.3662
|
Clavicle length (cm)
|
16.23 (1.23)
|
16.33 (1.26)
|
16.13 (1.22)
|
0.0362[a]
|
At the functional evaluation, the mean DASH score was 1.75, which is considered satisfactory.
Using a value of 10 points to analyze the least significant clinical difference (MCID),[21] scores were subdivided into satisfactory and unsatisfactory. Patients with an early
failure of the fixation method were considered as unsatisfactory outcomes for association
analyses. Among patients > 50 years old, 33.3% had unsatisfactory DASH scores (≥ 10),
whereas only 4.4% of patients < 50 years old had unsatisfactory scores (p = 0.0572) ([Table 3]). Two patients > 60 years old (100.0%) showed unsatisfactory DASH scores, differing
significantly from the group < 60 years old (p < 0.05), in which 6.7% of the patients had unsatisfactory scores. Among patients
with shorter waiting times until surgery (up to 7 days), no one had unsatisfactory
DASH scores; on the other hand, among those who waited > 7 days until surgery, 26.7%
had unsatisfactory scores (p < 0.05).
Table 3
Variable
|
n (%)
|
DASH
|
p-value
|
Unsatisfactory
|
Satisfactory
|
Frequency (%)
|
Frequency (%)
|
Age
|
|
|
|
|
≤ 42 years old (median)
|
19 (59.4)
|
1 (5.3)
|
18 (94.7)
|
0.2788
|
> 42 years old
|
13 (40.6)
|
3 (23.1)
|
10 (76.9)
|
|
≤ 50 years old
|
23 (71.9)
|
1 (4.4)
|
22 (95.6)
|
0.0572
|
> 50 years old
|
9 (28.1)
|
3 (33.3)
|
6 (66.7)
|
|
≤ 60 years old
|
30 (93.8)
|
2 (6.7)
|
28 (93.3)
|
0.0121[a]
|
> 60 years old
|
2 (6.2)
|
2 (100.0)
|
0 (0.0)
|
|
Gender
|
|
|
|
|
Female
|
1 (3.1)
|
0 (0.0)
|
1 (100.0)
|
1.0000
|
Male
|
31 (96.9)
|
4 (12.9)
|
27 (87.1)
|
|
Days until surgery
|
|
|
|
|
≤ 7 days (median)
|
17 (53.1)
|
0 (0.0)
|
17 (100.0)
|
0.0380[a]
|
> 7 days
|
15 (46.9)
|
4 (26.7)
|
11 (73.3)
|
|
Complaints
|
|
|
|
|
No
|
20 (62.5)
|
1 (5.0)
|
19 (95.0)
|
0.1361
|
Yes
|
12 (37.5)
|
3 (25.0)
|
9 (75.0)
|
|
Consolidation
|
|
|
|
|
No
|
2 (6.2)
|
2 (100.0)
|
0 (0.0)
|
0.0121[a]
|
Yes
|
30 (93.8)
|
2 (6.7)
|
28 (93.3)
|
|
Twelve-hole implants were used in 28 patients, and 5 cases (15.6%) required material
removal. Consolidation occurred in 30 patients (93.72%) after an average period of
17 weeks, and no pseudoarthrosis or infection was observed. As complications, there
were 2 cases of early failure after osteosynthesis; both patients were 61 years old
at the time and presented implant loosening, with no plate fracture: 1 within 1 week
after surgery (an alcoholic patient) ([Figure 5]) and the other within 8 weeks after surgery (a patient with type 2 diabetes). Both
underwent a new surgery for ORIF with plate and screws, but no bone graft, and progressed
with fracture consolidation.
Fig. 5 Detailing of one of the cases with early loosening.
The following complications were observed in the study population: pain on exertion
(5 patients – 15.6%), plate-related discomfort (6 patients – 18.8%), hypersensitivity
(2 patients – 6.2%), and pain at rest (1 patient – 3.1%). Paresthesia around surgical
incisions was not reported. The 2 cases of early implant loosening presented unsatisfactory
DASH scores (100.0%); in patients with consolidation, however, 93.3% of DASH scores
were deemed satisfactory (p < 0.05).
Discussion
There was no case of pseudoarthrosis or infection in our sample. We believe that the
technique here described spares soft tissues and the fracture focus, contributing
to the consolidation rate of 93.72% observed in our sample, similar to that reported
by Sohn et al.[22] Our patients presented good clinical, functional and radiographic outcomes, which
were in line with the literature. Mirzatolooei[4] observed similar consolidation rates between surgically and clinically treated patients;
the former, however, presented lower rates of vicious consolidation and shortening
and better DASH scores (mean score, 8.6). This author chose the method of absolute
stability and performed fixation with a reconstruction plate in the upper position,
obtaining pseudoarthrosis associated with infection.
The rate of early failure was similar to that reported by Wang et al.,[23] who described the same complication, implant loosening, in one of their patients.
Our unsatisfactory DASH scores were associated with older age and early fixation failure,
and may possibly require an reevaluation of the indication of such technique in this
age group; however, due to the observational nature of the study, we cannot say which
is the most important factor associated with this complication: bone quality or the
use of an unlocked implant.
The MIO technique has the benefit of using smaller incisions, avoiding large exposures
that can favor suture dehiscence, infections or pseudoarthrosis.[13] Incisions performed in the lateral and medial regions of the clavicle do not harm
the areas supplied by supraclavicular nerves,[24] preventing the development of paresthesia. Other authors corroborate the benefits
of the minimally invasive procedure. Jiang et al.[25] compared the outcomes from comminuted fractures of the clavicle treated using the
mini-open and ORIF surgical techniques. These authors described that patients treated
with the mini-open technique presented less dysesthesia, no hypertrophic scars, better
ipsilateral shoulder mobility and no pain. You et al.[26] reported that the MIO technique resulted in a lower rate of paresthesia at the anterior
chest and greater patient satisfaction when compared with the traditional surgical
method.
Another important analysis refers to implant removal procedures, which are common
in patients undergoing clavicle osteosynthesis. In our sample, 15.60% of the patients
required implant removal, consistent with the index reported by Sökucu et al.,[8] and lower than the 23% rate observed by Asadollahi et al.[27]
This fracture reduction method is unprecedented and based on retracted scapula positioning,
which is described by Kibler et al.,[28] ideal for shoulder function. In this technique, the scapula is externally and superiorly
rotated, posteriorly inclined and medially translated in relation to the chest. We
believe that this maneuver contributes to the alignment of fractured fragments of
the clavicle; such alignment was observed in all patients systematically submitted
to the maneuver during surgery. We also observed that additional devices, such as
Kirchner wires,[17] traction with a screw outside the plate[18] or small approaches to the fracture site were not required to sustain this position.[23] In addition to the scapular retraction maneuver, the unlocked implant in the superior
position also helps to reduce fragments, since cortical screws brings deviated inferiorly
fragments towards the plate. Implants in the anteroinferior position or those with
superiorly placed locked screws may not be useful to correct these deviations.
We used a 3.5-mm reconstruction plate, as it is an implant easily modeled according
to the shape of each clavicle. Some authors[8]
[25]
[26] perform the MIO technique with anatomical or premodeled implants, whereas others[17]
[18]
[22]
[23] share our philosophy of individualized reconstruction plate modeling for each case
but use locked 3.5-mm reconstruction implants. We prefer to use unlocked implants
because of their higher availability in Brazil, especially in the SUS. Alzahrani et
al.[29] evaluated 102 patients after clavicle osteosynthesis with 4 different implants (2.7-mm
and 3.5-mm reconstruction plates, premolded plate and 3.5-mm locked plate), and reported
that, despite biomechanical studies showing different tensile properties, there was
no difference between groups regarding consolidation or complication rate. We emphasize
that implant breaks were not observed, consistent with Silva et al.,[30] who reported no unlocked reconstruction plate rupture in their study on the surgical
treatment of deviated clavicle fractures using these devices or intramedullary nails.[30]
The positive points of our study are the high reproducibility of the technique, attesting
its internal validation, with low complication rates, no implant breaks, high consolidation
rates and satisfactory functional scores determined by an independent examiner. The
limitations of the study stem from its observational nature, since our controls are
the results of similar studies described by other authors. In addition, we believe
that our patients had complex comminuted fractures, but we emphasize that there was
no analysis of radiographic images for agreement between evaluators on their simple
or complex trait, and this can be considered a weakness of the study. Finally, we
believe that this technique must be disseminated in Brazil for external validation
and subsequent evaluation in studies with higher levels of evidence and comparison
with conventional open reduction procedures.
Conclusion
The MIO technique was satisfactory for the treatment of comminuted midshaft clavicle
fracture, with a high consolidation rate and a low complication rate.