Session 8a: Experimental
Session 8b: Sportstrauma
Torsdag den 23. oktober
13:00 – 14:30
Lokale: Stockholm/Copenhagen
Chairmen: Jan Duedal Rölfing / Martin Lind
73. The Göttingen Mini-Pig (GMP) as an Animal Model for Articular Cartilage Repair
Bjørn Christensen, Casper Foldager, Morten Olesen, Jan Rölfing, Steffen Ringgaard, Martin Lind
Ortopedic Research Laboratory, Aarhus University Hospital; Orthopedic Research Laboratory, Aarhus University Hospital; MR center, Aarhus University Hospital; Division of sports trauma, Aarhus University Hospital
Background: Several animal models are available for
preclinical testing of cartilage repair, but a
cost-effective and predictable large animal
model is needed to bridge the gap between
in vitro studies and clinical studies.
Ideally, the animal model should allow for
testing of clinically relevant treatments and
the biological response should be
reproducible and comparable to humans.
This allows for a reliable translation of
results to clinical studies.
Purpose / Aim of Study: This study aimed at verifying the GMP as a
pre-clinical model for articular cartilage
repair by testing several clinically available
surgical treatment options and evaluation
methods.
Materials and Methods: Thirteen fully mature GMPs were used. The
GMPs received bilateral trochlear
osteochondral drill-hole defects or chondral
defects (Ø 6mm). The defects were treated
with one of the following: Matrix-induced
autologous chondrocyte implantation
(MACI), microfracture (MFx), autologous-
dual-tissue transplantation (ADTT),
autologous bone graft, autologous cartilage
chips. Empty chondral and osteochondral
defects were used as controls. MRI and CT
were performed 3 and 6 month, histology
was performed at 6 month postoperative.
Findings / Results: The repair tissue varied in morphology from
non-cartilaginous fibrous tissue to
fibrocartilaginous tissue as seen on MRI, CT
and histology at 6 month. The worst results
were seen in the empty controls, the defects
treated with autologous bone graft and
defects treated with MFx. The best results
were achieved with the MACI treatment.
Conclusions: The outcomes of the applied treatments
were consistent with the outcomes in clinical
studies. The GMP model was easy to
handle, cost-effective and provided
predictable outcome. Based on this study,
we conclude that the GMP is a viable animal
model for articular cartilage research.
74. Collagen type IV in Articular Cartilage Damage and Repair
Casper Bindzus Foldager, Wei Seong Toh, Bjørn Borsøe Christensen, Martin Lind, Andreas H. Gomoll, Myron Spector
Orthopaedic Research Lab, Aarhus University Hospital; Faculty of Dentistry, National University of Singapore; Sports Trauma Clinic, Aarhus University Hospital; Cartilage Repair Center, Brigham & Women's Hospital; VA Tissue Engineering Lab, Harvard Medical School
Background: Chondrocytes are surrounded by a thin
layer of pericellular matrix (PCM). Collagen
type IV (COL4) is present in the PCM of
healthy chondrocytes. COL4 is composed of
three of six different alpha-chains. Three of
these alpha-chains contain angiogenesis
inhibiting domains in alpha-1 (arresten),
alpha-2 (canstatin), and alpha-3 (tumstatin),
but their presence in cartilage is unknown.
Purpose / Aim of Study: To identify the COL4 alpha-chains in
cartilage and describe its distribution of in
cartilage damage and repair.
Materials and Methods: In vitro: Human chondrocytes from 6
patients were cultured in standard 21%
oxygen and physiologic 1% oxygen for up to
6 days. Quantitative gene expression
analysis (RT-qPCR) was performed to
confirm the chondrogenic phenotype (Sox5,
Sox6, Sox9) and to investigate the presence
of the different COL4 alpha-chains 1-6.
In vivo: Distribution of collagen type IV was
investigated with immunohistochemistry in
normal cartilage (human, n=5), damaged
cartilage (human, n=5), clinically failed
repair (human, n=11), cartilage repair with
6-month follow-up (minipig, n=11).
Findings / Results: COL4 expression in normal chondrocytes
consisted of alpha chain 1 and 2. In normal
cartilage COL4 was restricted to the PCM.
Damaged cartilage contained significantly
less COL4 in the PCM compared with
normal cartilage. In minipigs with fibrous
repair matrix COL4 was found in the
extracellular matrix (ECM) and not the PCM.
In fibrocartilage COL4 was also seen in the
PCM and the interterritorial matrix. In
hyaline repair tissue COL4 was restricted to
the PCM. In failed repair COL4 was found in
the PCM of 0-75% of the cells depending on
tissue morphology and treatment.
Conclusions: COL4 in cartilage contain the angiogenesis
inhibitors arresten and canstatin. The
distribution of COL4 is changed in cartilage
repair compared to normal cartilage.
75. Reduced force development in rat soleus muscle after exposure to Botulinum Neurotoxin A
Sofie Gjessing, Ole Rahbek, Juan Manuel Shiguetomi, Ole B. Nielsen, Bjarne Møller-Madsen
Dept. of Children's Orthopaedics, Aarhus University Hospital; Department of Biomedicine, Aarhus University
Background: A fast force development at the
beginning of a muscle contraction is an
important functional aspect of
locomotion such as gait. In both human
and rat motor function this can be
achieved by firing double pulses
(doublets) with an inter-pulse interval
(IPI) as short as 1.6 ms. We hypothesize
that Botulinum Neurotoxin A (BoNT)
reduces the ability of the neuromuscular
junction to transmit doublets and
therefore also reduces their
potentiating effect on force development.
Purpose / Aim of Study: We aimed to examine the effect of BoNT
on force potentiation resulting from
doublet stimulation in skeletal muscle.
Materials and Methods: Experiments were performed on isolated
soleus muscle with intact motor nerve
from juvenile Wistar rats that had been
given intramuscular injections of BoNT
1-4 days prior to ex vivo examinations
of contractile force.
Findings / Results: BoNT caused a progressive decline in
nerve-stimulated tetanic force of the
muscle preparations. In controls,
nerve-stimulated doublets increased
twitch force to ~200% of force of a
single pulse when IPI was 2 ms and 230%
for an interval of 4 ms. This
potentiation was, however, attenuated by
BoNT in a manner that depended on the
reduction in nerve-stimulated force and
the IPI. When tetanic force stimulated
via the nerve was reduced to 0-39% of
force produced by direct stimulation of
the muscle fibres, force potentiation,
resulting from nerve stimulation by
doublets with an IPI of 2 ms, was
significantly reduced (P<0.01, one-way
ANOVA). No significant effects was
observed at an IPI > 4 ms.
Conclusions: Treatment with BoNT in vivo reduced the
ability of the neuromuscular junction to
transmit high-frequency doublets in
skeletal muscle. This indicates that
treatment with BoNT may interfere with
motor function during locomotion, which
could compromise gait.
76. Inhibition of Micromotion induced Osteolysis in a Sheep Hip Arthroplasty Model
Thomas Jakobsen, Søren Kold , Juan Shiguetomi-Medina , Jørgen Baas, Kjeld Søballe, Ole Rahbek
Ortopædkir. Forskningslab., Aarhus Universitets Hospital; Ortopædkir. afd., Aalborg Universitets Hospital; Ortopædkir. Forskningslab, Aarhus Universitets Hospital; Ortopæd. Afd., Aarhus Universitets Hospital
Background: Aseptic loosening is the leading indication
for revision surgery of a total hip
replacement. It has previously been shown
that early micromotion of a total hip
replacement is associated with early aseptic
loosening. One way to reduce the impact of
the early micromotion on implant fixation
could be with the use of bisphosphonates
(BP). These compounds are strong
inhibitors of bone resorption.
Purpose / Aim of Study: The aim of this study was to investigate
whether local treatment with BP would
reduce bone resorption around an
experimental implant subjected to
micromotion.
Materials and Methods: One micromotion implant were inserted into
each medial femoral condyle in ten sheep.
The micromotion device consists of an
anchor bearing a PMMA implant and a PE
plug. The 7.5 mm PMMA implant is placed
exact-fit into a 7.5 mm bone cavity. During
each gait cycle the PE plug will transfer load
through the anchor and make the PMMA
implant axially piston 0.5 mm.
During surgery one of the femoral condyles
were locally treated with 0.8 mg zoledronic
acid. The other condyle served as control.
Bone-implant specimens were harvested
after 12 weeks of observation. Each
specimen were embedded and vertically cut
for histomorphometrical analysis.
Findings / Results: Histological evaluation showed a fibrous
capsule around both the control and BP
implants. Histomorphometrical analysis
showed that 97% of the surface on both
control and BP implants were covered by
fibrous tissue (p=0.7). However, the BP was
able to preserve bone in a 1 mm zone
around the implants (66% bone volume
fraction for BP vs. 57% bone volume
fraction for control, p = 0.02).
Conclusions: This study indicates that local treatment with
BP can not prevent the formation of a
fibrous capsule around an implant subjected
to micromotion. However, BP is able to
reduce resorption of peri-prosthetic bone.
77. Sheep model reflecting glucocorticoid induced osteoporosis in postmenopausal women
Christina Møller Andreasen, Ming Ding, Søren Overgaard, Peter Bollen, Thomas Levin Andersen
Department of Ortopaedics & Traumatology O, Institute of Clinical Research, Odense University Hospital, University of Southern Denmark; Department of Orthopaedics & Traumatology O, Institute of Clinical Research, Odense University Hospital, University of Southern Denmark; Biomedicine Laboratory, University of Southern Denmark; Department of Clinical Cell Biology, Institute of Regional Health Services Research, Vejle-Lillebælt Hospital, University of Southern Denmark
Background: Sheep are often used as models for human
osteoporosis, but it has not been verified
whether the bone remodelling of sheep is
comparable to human.
Purpose / Aim of Study: Here we investigate whether the bone loss
in glucocorticoid treated ovariectomised
sheep results from a similar bone
remodelling defect as in osteoporotic
postmenopausal women treated with
glucocorticoids.
Materials and Methods: Ten sheep were ovariectomised and treated
with prednisolone for 7 months. Ten
untreated sheep served as control. The
bone structure, selected histomorphometric
parameters and the serum level of bone
biomarkers were evaluated.
Findings / Results: Ovariectomy and glucocorticoid treatment
induced a significant bone loss after 7
months. The extent of bone surfaces
colonized by osteoclasts was unchanged,
while the resorption marker CTX had a
significant periodically elevation peaking
after one month. The bone formation marker
osteocalcin was consistently reduced after
one week, and the extent of formative
osteoid surfaces was almost undetectable
after 7 months. The extent of reversal
surfaces was significant increased after 1
month, covering almost 50% of the bone
surfaces after 7 months. Most of these were
arrested reversal surfaces without any
neighbouring osteoclasts or osteoid
surfaces, supporting that the bone formation
and resorption were uncoupled during the
reversal phase. The arrested reversal
surfaces had a significantly reduced cell
density and immunoreactivity for the
osteoblastic markers runx2, osterix and
SMA.
Conclusions: In sheep the bone loss results from an
uncoupling of the bone formation and
resorption during the reversal phase, as
described in osteoporotic postmenopausal
women treated with glucocorticoids, making
it a relevant preclinical model for studying
orthopaedic implant and biomaterial
research under osteoporotic conditions.
78. Micromotion Induced Osteolysis in a Sheep Hip Arthroplasty Model
Thomas Jakobsen, Søren Kold , Jørgen Baas , Kjeld Søballe, Ole Rahbek
Ortopædkir. Forskningslab., Aarhus Universitets Hospital; Ortopædkir. afd., Aalborg Universitets Hospital; Ortopædkir. Afd. , Aarhus Universitets Hospital; Ortopæd. Afd., Aarhus Universitets Hospital
Background: Aseptic implant loosening might occur when
peri-prosthetic bone anchorage is replaced
by a fibrous membrane. It could be that the
first step in the osteolytic cascade is
micromotion-induced formation of a fibrous
membrane around the implant.
Purpose / Aim of Study: The aim of this study was to investigate
whether implants subjected to micromotion
would be able to induce bone resorption
and formation of a fibrous membrane
without the presence of wear-debris
particles.
Materials and Methods: One micromotion implant (T12) were
inserted into one of the medial femoral
condyle in ten sheep. The micromotion
device consists of an anchor bearing a
PMMA implant and a PE plug. The 7.5 mm
PMMA implant is placed exact-fit into a 7.5
mm bone cavity. During each gait cycle the
PE plug will transfer load through the
anchor and make the PMMA implant axially
piston 0.5 mm.
After 12 weeks of observation the bone
specimens were harvested and a post-
mortem control implant (T0) was inserted
into the contra-lateral medial femoral
condyle. Each specimen were embedded
and cut for histomorphometrical analysis.
Findings / Results: Histomorphometrical evaluation showed
that the T12 implant surface was covered by
fibrous tissue (93% for T12 vs. 0% for T0, p
<0.001). The control implants were covered
by lamellar bone (91% for T0 vs. 4 % for
T12, p < 0.001). No difference was found
with respect to the volume fraction of
lamellar bone in a 1 mm zone around the
implants (57% for T12 vs. 48% for T0, p =
0.2).
Conclusions: This study indicates that micromotion alone
is sufficient to induce osteolysis and a
fibrous membrane around an implant.
79. Vancomycin is superior to Plectasin against Staphyloccus aureus periprosthetic osteomyelitis in rats.
Niels H. Søe, Nina Vendel-Jensen, Asger Lundorff-Jensen, Janne Koch, Steen Sejer Poulsen, Helle Krogh Johansen
Hand Section,Department of Orthopaedic, Gentofte University Hospital; Department of Anaesthesiology,Intensive care and Operations, Gentofte University Hospital; Faculty of Health and Medical Sciences, University of Copenhagen; Biomedical Department,Panum, Institute, University of Copenhagen; Department of Clinical Microbiology, Rigshospitalet, Denmark
Background: Commonly used antibiotics cannot
always control S. aureus associated
infections in orthopaedic implants
Purpose / Aim of Study: We investigated the ability of
Vancomycin and Plectasin to eradicate
S. aureus in a knee prosthesis model of
osteomyelitis in rats. We compared
Plectasin in a 20 and 40 mg
concentration to Vancomycin 40 mg, all
antibiotics were given i.p. daily. Plectasin
is a peptide antibiotic with therapeutic
potential from a saprophytic fungus.
Materials and Methods: Thirty Sprague-Dawley rats had
prosthesis inserted and divided into
three groups (N=10) Vancomycin
including 2 controls and two Plectasin
groups (N= 10) 20 mg and (N= 10) 40
mg including 2 controls in each groups.
All groups were infected with S. aureus
MN8,ica+103 in the tibia and the femur
marrow before insertion of the
prosthesis. Control rats were given
NaCl i.p. After two weeks, the rats were
sacrificed and all specimens were
analysed.
Findings / Results: One rat in the 20 mg Plectasin group and
four in the 40 mg Plectasin group died of
anaphylactic shock (histamine release).
The 20 and 40 mg Plectasin groups both
showed a decrease of bacteria but it
was not as efficiently eradicated as in
the Vancomycin group.
Conclusions: Plectasin treatment against S. aureus
osteomyelitis reduced the infection.
However, Plectasin released histamine
strongly after one day and some of the
rats died especially in the 40 mg group.
In contrast, Vancomycin reduced the
infection significantly in almost of the
parameters.
80. Human chondrocytes cultivated on modified polystyrene conserve their chondrogenic phenotype in vitro
Natasja Leth Jørgensen, Dang Le, Casper Foldager, Martin Lind, Helle Lysdahl
Orthopaedic Research Laboratory, Aarhus University Hospital; Interdisciplinary Nanoscience Center, iNANO, Aarhus University; Sports Trauma Clinic, Aarhus University Hospital
Background: Autologous articular chondrocytes tend to
dedifferentiate under prolonged expansion
culture ex vivo. Porous scaffolds have
been widely used to guide cells and grow
new tissue.
Purpose / Aim of Study: In this study, we investigated the influence
of precipitant induced porosity
augmentation (PIPA) modified polystyrene
surface on human chondrocytes (HCs)
cultured in vitro. We hypothesized, that
culturing HCs on 2D PIPA modified
surfaces would conserve their phenotype.
Materials and Methods: The modification of polystyrene was made
by the technique precipitant induced
porosity augmentation (PIPA). Polystyrene
was immersed with 1,4 dioxane and ozone
treated prior to cell seeding. HCs were
enzymatically isolated from cartilage
biopsies collected from the inter-condylar
groove in the distal femur. Isolated
chondrocytes were expanded to passage
1 (P1) in DMEM/F12 supplemented with
10% FCS, 5 ng/mL bFGF, 1 ng/mL TGFβ3,
and 1:100 penicillin-streptomycin (P/S).
Chondrocytes in P1 were then seeded on
PIPA modified polystyrene surfaces or on
traditional monolayer (on a plan
polystyrene surface) with 10,000 cells/cm2
in DMEM/F12 supplemented with 10% FCS
and 1:100 P/S. HCs were cultivated until P4
and samples were collected for quantitative
RT-PCR at each passages P1-P4.
Toluidine blue and collagen II stains were
performed on P2 HCs cultivated in pellets,
1×106 cells/mL, for 28 days.
Findings / Results: The PIPA surface promoted chondrogenic
differentiation of HCs compared with
traditional monolayer culture evident by
higher gene expression of COL II, and the
differentiation indices COLII/COLI and
AGG/COLI. HCs expanded on PIPA
surfaces prior to pellet formation revealed a
better chondrogenicity by more synthesis
of proteoglycans and collagen II.
Conclusions: Cultivation of HCs on the PIPA modified
surface seems to conserve the
chondrogenic phenotype.
81. Tunnel malpositioning in knee ligament reconstructions Denmark 2005-12
Thomas Hansen, Kim Lyngby Mikkelsen, Michael Rindom Krogsgaard
Section for Sportstraumatology M51, Bispebjerg Hospital; , The Patient Compensation Association
Background: Suboptimal positioning of tunnels is
stated as the reason for cruciate
ligament revision in 27 % of 1.866
operations reported to the Danish
Kneeligament Reconstruction Register
(DKRR) 2005-13. It is also the most
common reason for compensation
from The Patient Compensation
Association (PCA) to patients after
knee ligament reconstruction.
Purpose / Aim of Study: To describe the characteristics of
tunnel malpositioning in knee ligament
reconstruction reported to PCA and to
evaluate causes and possible means
of prevention.
Materials and Methods: From PCA patients with a reported
complication 2005-2013 after knee
ligament reconstruction were identified,
and details in cases of tunnel
malpositioning were studied. This was
combined with information about the
number of operations/year for each
clinic (< 10, 10-50 and >50), if it was a
public or private clinic and technique
for femoral tunnel positioning.
Findings / Results: 92 malpositions were accepted for
compensation. Of 52 malpositions in
femur, 38 were anterior and 12 were
vertical. Of 29 malpositions in tibia, 9
were anterior, 7 posterior and 13
medial, some perforating the medial
tibial plateau. Combined malposition in
femur and tibia was seen in 11. The
incidence of tunnel malpositioning was
highest in clinics with < 10
reconstructions/year (2,26 %), medium
in clinics with 10-50
reconstructions/year (0,69 %), and
lowest in clinics with > 50/year (0,28 %)
(p < 0,05). 73 femoral tunnels were
placed by transtibial (TT) technique
and 11 by anteromedial (AM)
technique – about 1/3 of all operations
were done with AM technique and 2/3
with TT.
Conclusions: If 27 % of revisions were caused by
tunnel malpositioning, less than 21 %
of these had been reported to PCA.
AM technique was less frequently
connected to malpositions than TT
technique. Routine seemed to be the
best prevention against tunnel
malpositioning.
82. One-year follow-up in the Danish Knee-ligament Reconstruction Register (DKRR) can be increased to 90 %
Jonathan Bjerre, Peder Klement, Bo Sparsø, Michael Krogsgaard
Department of sports traumatology, Bispebjerg; Department of orthopedic surgery, Bispebjerg; Center of health, Region Hovedstaden
Background: : The 1-year follow-up examination after
ACL-reconstruction is a key quality
parameter in DKKR. However, in the year
report 2013 follow-up was reported for
only 49,2 % (for Region Hovedstaden (RH)
45,6 %), which is a serious problem for
the validity of the register. It has not
been investigated why the reported
follow-up is so low. The standard of
>60% is based on the assumption that
these patients are mobile and less
motivated for follow-up.
Purpose / Aim of Study: To evaluate: completeness of 1-year
follow-up after ACL-reconstruction in
2012 in RH, reasons why it is
incomplete, ways to increase
completeness and whether the official
standard of > 60 % is realistic.
Materials and Methods: Patients who were registered with an
intervention classified as KNGE45 or
KNGE46 in 2012 the databases of 8 public
and private hospitals in RH were
identified, and their hospital files
were studied. For patients who had no
one-year follow-up it was checked if
they had been invited. Data were
compared with extracts from the DKRR.
Findings / Results: Of 931 operated patients, 814 were
registered in DKKR (87,4 %). The
follow-up rate reported to DKRR was 34,9
% (range 0-68 %). The actual follow-up
rate was 64 % (range 30 – 91 %). There
were marked differences in the way
follow-up was planned. Most important
reasons for lacking follow-up were
failure to report to DKRR, no standard
strategy for follow-up, technical
problems with DKRR and unclear courses
due to other operations. Less than 10 %
of patients refused to show up.
Conclusions: A reported follow-up rate >90% is
realistic if patents are invited at a
reasonable time before follow-up, if
they are re-invited once in case they
don’t show up and if hospitals report
actual follow-ups. Technically,
reporting should be easier and robust to
IT evolution.
83. Normative profiles for hip strength and flexibility in elite footballers
Andrea Mosler, Kay Crossley, Kristian Thorborg, Adam Weir, Andreas Serner , Per Hölmich
Sports Groin Pain Center, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar; , University of Queensland; Sports Orthopedic Research Center - Copenhagen, Arthroscopic Center Amager; Sports Groin Pain Center & SORC-C, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar & Arthroscopic Ceneter Amager
Background: Normative profiles for hip/groin strength
and flexibility have not been established in
footballers.
Purpose / Aim of Study: The primary aim of this study was to
determine these normative profiles.
Materials and Methods: 345 males (18-40) years, playing
professional football in the Qatar Stars
League were evaluated. Strength was
measured using a hand held dynamometer
with an eccentric break test in side-lying for
hip adduction (ADD) and abduction (ABD),
and squeeze test in supine with 45° hip
flexion. Flexibility measures included; hip
internal rotation (IR) in both 90° flexion and
prone, hip ABD in side-lying and bent knee
fall out (BKFO). Demographic information
was collected and the effect on the profiles
was analysed. Pain on each testing
procedure was recorded.
Findings / Results: Normative values for strength were as
follows (mean±SD); ADD non-
dominant=3.2±0.6 Nm/kg,
dominant=3.1±0.6 Nm/kg; ABD both legs=
2.4±0.4 Nm/kg; ADD:ABD ratios non-
dominant=1.4±0.3, dominant=1.3±0.3;
Squeeze test=3.2±0.8 N/kg. Flexibility; IR in
flexion both legs=37±8°, IR in prone non-
dominant=36±8°, dominant=37±8°, ABD in
side lying both legs=47±8°, BKFO non-
dominant= 13.5±4.1cm,
dominant=13.7±4.1cm. Leg dominance and
a past history of injury had no clinically
relevant effect on the strength and flexibility
profiles. However, pain on squeeze testing
significantly reduced the score for that test
(p≤0.05).
Conclusions: Clinicians can confidently compare the
strength and flexibility profile with the non-
injured leg when assessing a footballer with
unilateral pain. Pain on testing resulted in
lower squeeze values, but a past history of
hip or groin injury did not affect these
profiles. Future studies will examine the
predictive value of these measures for
injury.
84. Complications after kneeligament reconstruction in Denmark 2005-2012 as reported to The Patient Compensation Association (PCA)
Thomas Hansen, Kim Lyngby Mikkelsen, Michael Rindom Krogsgaard
Section for Sportstraumatology M51, Bispebjerg Hospital; , The Patient Compensation Association
Background: The number and distribution of
complications to kneeligament
reconstruction is widely unknown, as
many reports of complications origin
from centers with selected patient
groups. The Danish Kneeligament
Reconstruction Register only report
some types of complications, and the
follow-up rate is quite low.
Purpose / Aim of Study: To describe complications to
kneeligament reconstruction in
Denmark as reported to PCA, related
to number of reconstructions.
Materials and Methods: From PCA patients with a claimed
complication after kneeligament
reconstruction 2005-2012 were
identified, excluding reconstruction of
patellar ligaments. The files for each
patient were studied, the complications
were grouped and combined with
information about rejection or
compensation.
Findings / Results: Total number of reconstructions was
22.321. From 493 claimed cases, 261
(=1,17 %) were recognized for a
compensation (total 35.558.205 DKK =
136.238 DKK/complication = 1.593
DKK/reconstruction). The 8 most
common complications
(claimed/recognized/total
compensation in DKK): Tunnel
malpositioning (104/92/13.221.872),
deep infection (97/66/5.771.059),
nerve damage (59/39/8.328.102),
unrecognized diagnosis – typical
undiagnosed multiligament injury
(23/22/1.878.326), pain
(46/18/1.022.676), arthrofibrosis
(22/6/4.957.405), instrument failure
(19/12/1.357.566), thromboembolic
events (9/8/631.138). The 10 most
expensive (6 tunnel malpositions)
complications cost 15,8 mio DKK. Only
six of 66 patients with infection had not
received prophylactic antibiotics.
Complications were not significantly
more common in private (1,5 % of
registered operations in DKRR) than in
public (1,2 %) clinics, with individual
variations.
Conclusions: Tunnel malpositioning is the most
common complication, whereas nerve
damage and arthrofibrosis are the
(relatively) most expensive
complications. Thromboembolic
complications were rare.