Absorbable Stabilisation of the Bar inMinimally Invasive Repair of Pectus Excavatum
M. Torre1, V. Jasonni1, C. Asquasciati1, S. Costanzo1, M. V. Romanini2, P. Varela3
1 Pediatric Surgery, G. Gaslini Institute, Genova, Italy2 Plastic Surgery, IST, University of Genova, Genova, Italy3 Pediatric Surgery, Calvo Mackenna Hospital, Santiago, Chile
Results: The surgical technique for the stabilisa-
tion of the bar was identical in both groups, but
Introduction: The minimally invasive repair of
in group 1 the stabiliser was fastened to the bar
pectus excavatum has become the preferred
with a steel wire, while in group 2 polyglycolic
technique in most centres. One of the most im-
sutures were used. No differences in local dis-
portant technical points for the final result is sta-
comfort or postoperative pain were observed be-
bilisation of the bar, usually obtained by one or
tween the groups. The LactoSorb® stabiliser was
two metal stabilisers. Recently, long-term ab-
palpable for at least 6–9 months, and progres-
sorbable stabilisers have become available (Lac-
sively disappeared at 9–12 months. In group 1
toSorb®, Biomet, Jacksonville, FL, USA). Made of
we observed 6 local complications. In particular,
poly-L-lactic and polyglycolic acid, they have
two patients presented with infection, one of
been introduced with the aim of reducing local
them associated with a skin lesion and opening
discomfort and making removal of the bar easier.
over the metallic stabiliser (revision of the wound
Their efficacy for the stabilisation of the bar has
was performed). Another patient developed a
not been proved yet. In this paper we compare
thoracic wall haematoma after suffering a trauma
the surgical outcome in two groups of patients,
over the metallic stabiliser, 13 months after oper-
one treated with metallic and the other with ab-
ation. Three patients developed a seroma. In
group 2 we observed 3 subcutaneous swellings
Material and Methods: A total of 280 patients
at the site of the LactoSorb® stabiliser at 6, 8 and
underwent pectus excavatum repair using a Nuss
9 months after the operation. We did not observe
technique in two centres. In 194 patients (group
either skin lesions or infections. In the group with
1), operated on since 2001, the metallic stabiliser
metallic stabiliser, 3 patients (1.5 %) had bar dislo-
was used. In 86 patients (group 2), operated on
cation, while we did not observe bar instability in
since February 2007, the LactoSorb® stabiliser
the group with LactoSorb® stabiliser.
was preferred. We compared both groups in
Conclusions: LactoSorb® stabiliser is safe and ef-
terms of surgical details, local symptoms or com-
fective for stabilising the bar in pectus surgery.
plications, and bar instability rate.
We suggest its routine use as it appears to be less
traumatic and could make bar removal easier.
Recently, absorbable stabilisers have become
available (LactoSorb® stabiliser, Biomet, Jackson-
Bar displacement is one of the most serious com-
ville, FL, USA). They are made of poly-L-lactic and
plications of minimally invasive repair of pectus
polyglycolic acid, and are completely absorbed by
excavatum (MIRPE) [7, 8]. Many techniques have
12 months. This material has been used for many
been proposed to increase the stability of the bar
years in other kinds of surgery (craniofacial, or-
[2, 3,10]. Most surgeons fix the bar with the help
thopaedic surgery), and has been proven to be
of one or two metallic stabilisers [4, 6]. At the
safe in children [1]. The absorbable stabiliser was
time of bar removal, the metallic stabiliser has
introduced in pectus surgery with the aim of re-
to be dissected and detached from the bar; in
ducing local complications and discomfort, and
cases with a bilateral stabiliser two incisions
making bar removal easier. In cases requiring bi-
lateral stabilisation the double incision is avoided.
Torre M et al. Absorbable Stabilisation of …
This document was prepared for the exclusive use of Michele Torre. Unauthorized distribution is strictly prohibited.
The efficacy of the LactoSorb® stabiliser for the stabilisation ofthe bar has not been proved yet. The aim of our paper was tocompare two groups of patients, one treated with metallic andthe other with absorbable stabilisers.
This is a retrospective study on patient series from two centreswhich have used MIRPE and the Nuss technique [6] since 2001and 2005, respectively. The technical details for stabilisationare the same for both centres: one stabiliser on the left, 4stitches between the bar and the adjacent ribs on the right.
The LactoSorb® stabiliser has been used in both centres since2007. Once introduced, in one centre it was used in all patients;in the other centre, the LactoSorb® stabiliser has been used in allpatients under 15 years of age, while the metallic stabiliser was
were passed through the holes of the stabiliser fixing it to the
still preferred for patients over 15 years of age (considered at
pectoral muscles. This manoeuvre was easier in patients in
greater risk of destabilisation). The LactoSorb® stabiliser has the
group 2, because the surgeon was able to see the needle through
same shape and size as the metallic one, it has the same holes
No differences were observed between the groups with regard to
All patients operated with MIRPE in both centres were consid-
postoperative pain or hospitalisation. In both groups, pain was
ered. Patients were divided into two groups. Group 1 (metallic
managed during the first three days by a peridural infusion of
stabilisation) included all patients in whom stabilisation was
fentanyl and levobupivacaine, associated with intravenous bo-
achieved with a left-sided metallic stabiliser (172 cases) and a
luses of paracetamol and/or ketorolac. After the fourth day, only
minority of patients (22 cases) at the beginning of our experi-
oral paracetamol and codeine were given. Pain was evaluated
ence who underwent stabilisation on both sides. The total num-
with a pain numeric score from 1 to 10, and analgesia doses were
ber of patients included in group 1 was 194.
adjusted accordingly. None of the patients in both groups re-
Group 2 (LactoSorb® stabilisation) included all patients operated
ported significant (requiring medication) local discomfort.
on since February 2007 in one centre and since March 2007 in
The LactoSorb® stabiliser was palpable under the skin for 6–9
the other, in whom stabilisation was achieved by an absorbable
months. After approximately 3 months it started to change its
LactoSorb® stabiliser on the left side. None of the patients in this
shape and became slightly mobile. At 6–9 months the stabiliser
group received bilateral stabilisers. The total number of patients
was progressively less palpable and between 9 and 12 months it
included in group 2 was 86. Two bars (and two stabilisers) were
inserted only in very selected cases (4 patients in each group),
Local complications were reported in 6 cases of group 1 (3 %).
when one bar alone was unable to correct the thoracic defect.
Wound infection was observed in 2 cases. In one of them (a very
The following were evaluated for both groups: technical details,
slim 13-year-old boy) the skin over the metallic stabiliser started
discomfort associated with the presence of the stabiliser, local
to damage and opened at 2 months after the operation. Three
complications, instability rate. In all patients of group 2 the bar
weeks after wound revision, the skin opened again; a Goretex
is still in site, so we could not compare bar removal between the
sheet was then placed over the metallic stabiliser and the skin
was closed; no other troubles were observed. Another patient
Student t-test was used for statistical analysis to compare the
developed a haematoma of the thoracic wall at the site of the
parameters of the two groups (age of the patients, pain score,
stabiliser after a local trauma, at 13 months from the operation.
Three patients developed a seroma (two of them with bilateralmetallic stabilisers). In group 2 we did not observe any infections. Three patients
(3.5 %) developed a subcutaneous collection at the site of the sta-
biliser at 6, 8 and 9 months from the operation, respectively. We
MIRPE according to Nuss [5] was performed in a total of 280 pa-
tried to puncture it: in two of them we obtained few ml of fluid
tients in the two centres. In group 1 (194 patients with metallic
(culture examination was negative), in the third case no free
stabilisation) the follow-up ranged from 6 to 87 months, with a
liquid was collected. In all of these cases the absorption was
In group 2 (86 patients with LactoSorb® stabilisation) the mean
The bar was instable in 3 cases (1.5 %) of group 1, while none of
follow-up was 12 months, with a standard deviation (SD) of 4.7,
and a range from 5 to 20 months. The mean age of group 2 pa-tients was 15.5 (3.4 SD), and ranged between 6 and 22 years. Nostatistical differences were found between the groups regarding
The technical details of the stabilisation were similar for both
The lateral stabiliser has been demonstrated to be a very effec-
groups. The metallic stabiliser was fastened to the bar with a
tive tool which contributes to the stability of the bar after pectus
steel wire, while the LactoSorb® stabiliser was secured with a
repair [4, 5]. However, metallic stabilisers can become a source
polyglycolic suture. In both groups other absorbable stitches
of trouble, and some authors prefer not to use them. An in-
Torre M et al. Absorbable Stabilisation of …
This document was prepared for the exclusive use of Michele Torre. Unauthorized distribution is strictly prohibited.
creased incidence of wound complications (dermatitis, seroma,
In conclusion, this is the first report in which the results of ab-
infections) associated with the use of local stabilisers has been
sorbable stabilisation are shown. The LactoSorb® stabiliser is
safe and as effective as the metallic stabiliser in fixing the bar.
The introduction of a new absorbable stabiliser (LactoSorb®) had
We suggest the routine use of the LactoSorb® stabiliser, as it ap-
the aim of reducing these complications and making bar remov-
pears to be less traumatic and requires less dissection at the time
al easier. This material has previously been used for a long time
in humans without adverse effects; however one possible con-cern could regard the efficacy of a device which loses its strength
and disappears within a few months. Although our results arepreliminary and a longer follow-up is required, the most impor-
tant finding of the present study is the efficacy of LactoSorb® sta-
1 Barry L, Eppley. Use of resorbable plates in pediatric facial fractures.
biliser in fixing the bar. According to our data, it appears even su-
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2 Hebra A, Swoveland B, Egbert M, Tagge EP, Georgeson K, Othersen Jr HB,
perior to metallic stabilisers, but in our opinion this difference
Nuss D. Outcome analysis of minimally invasive repair of pectus exca-
was not significant, because the patients’ numbers and surgeons’
vatum: review of 251 cases. J Pediatr Surg 2000; 35: 252–257; discus-
experience were different between the two groups. The efficacy
of LactoSorb® in stabilising the bar over a longer period, despite
3 Hebra A, Gauderer MW, Tagge EP, Adamson WT, Othersen Jr HB. A sim-
its progressive absorption after few months, could be explained
ple technique for preventing bar displacement with the Nuss repair ofpectus excavatum. J Pediatr Surg 2001; 36: 1266–1268
by the formation of adhesions and calcifications around the bar.
4 Hosie S, Sitkiewicz T, Petersen C, Göbel P, Schaarschmidt K, Till H, Noat-
Local complications were rare in both groups. One specific com-
nick M, Winiker H, Hagl C, Schmedding A, Waag KL. Minimally invasive
plication of the absorbable stabiliser was the subcutaneous col-
repair of pectus excavatum – the Nuss procedure. A European multi-
lection we observed in three cases during the process of absorp-
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5 Nuss D, Croitoru DP, Kelly Jr RE, Goretsky MJ, Nuss KJ, Gustin TS. Review
tion of the LactoSorb®. Actually this was clinically not particu-
and discussion of the complications of minimally invasive pectus ex-
larly relevant and culture examinations excluded infection. We
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think that this fluid or semi-fluid collection may be due to the
6 Nuss D, Kelly RE, Croitoru DP, Katz ME. A 10 year review of a minimally
dissolution and substitution of the LactoSorb® material during
invasive technique for the correction of pectus excavatum. J Pediatr
the absorption process, and therefore we consider it more as part
7 Park HJ, Chung WJ, Lee IS, Kim KT. Mechanism of bar displacement and
of this process than as a true complication. In contrast, the me-
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observed in group 1, in particular infections, opening of the skin
8 Petersen C, Leonhardt J, Duderstadt M, Karck M, Ure BM. Minimally in-
vasive repair of pectus excavatum – shifting the paradigm? Eur
Another specific advantage of the absorbable stabiliser was an
9 Saxena AK. Pectus bar removal after minimal invasive repair of pectus
easier and faster dissection of the tip of the bar at the time of its
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removal. Actually, the dissection of the metallic stabiliser, often
covered by scar tissue or bone, and detachment of the stabiliser
10 Uemura S, Nakagawa Y, Yoshida A, Choda Y. Experience in 100 cases
from the bar, can be sometimes quite difficult and time consum-
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11 Watanabe A, Watanabe T, Obama T, Oshawa H, Mawatari T, Ichimiya Y,
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Torre M et al. Absorbable Stabilisation of …
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