Session 4 : YODA Best Paper
15. November
11:00 - 12:00
Lokale: Auditorium
Chair: Christian Bredgaard Jensen and Claus Varnum
31. Field sterility is a safe procedure in carpal tunnel release
Tobias Christian Bisgaard1, Kjærgaard Thillemann Janni 1,2, Bæk Hansen Torben 1,2
1. Department of Orthopaedics, University Clinic for Hand, Hip and Knee
Surgery, Gødstrup Hospital, Herning
2. Department of Clinical Medicine, Aarhus University
Background: In February 2023, field sterility (FS) was
implemented for outpatient surgery of minor
hand surgery at Gødstrup Hospital, as these
procedures may be performed safely in FS
alone.
Aim: We aimed to compare infection rates after
treatment of carpal tunnel syndrome (CTS)
performed in standard sterility with full
surgical draping to FS alone.
Materials and Methods: In a retrospective cohort study 140 patients
(58 men) with a mean age of 61 years
(range 21-95) were included after surgical
treatment of CTS in FS alone, performed as
open or endoscopic carpal tunnel release
(CTR). In 2022, the year before
implementing FS, 213 patients (81 men)
with a mean age of 63 years (range 17-90)
underwent similar surgical procedures
under standard sterility settings and were
selected as control group.
Infection was registered from the hospital
data charts, including samples performed at
the hospital or by the patient’s general
practitioner. In case of a positive
bacteriological sample within the first 14
days after surgery, infection was registered
either as superficial without needs for
surgery or deep with the need of surgical
intervention.
Results: The control group and FS group were
comparable on age, gender, operated side
and surgical technique. There were 4
superficial infections (3%) in the FS group,
which was a significantly lower rate
compared to 16 superficial and 1 deep
(open CTR) infection (12%) in the control
group (p=0.046). The main agent causing
infection was streptococcus aureus (81%).
Three superficial infection was diagnosed
after endoscopic CTR in 142 patients (2%),
which is significantly less compared to 18
infections diagnosed after open CTR in 211
patients (9%), regardless the sterility
procedure (p=0.03). However, patients
treated by open CTR was mean 22 years
(95% CI 19-25) older open CTR patients
(p=0.000).
Interpretation / Conclusion: Field sterility for a minor hand surgical
procedures including open and endoscopic
CTR, is safe and without increased risk of
infection. Thus, FS reduces the amount of
draping’s and thereby the costs.
Furthermore, endoscopic CTR surgery
technique showed less infection compared
to the open technique but may be
associated to higher age.
32. New reference values of central knee anatomy for 8-16-year-old children
Emma Hvidberg1,2, Bjoern Vogt3, Jan Duedal Rölfing1,2, Georg Gosheger4, Bjarne Møller-Madsen1,2, Ahmed A Abood1,2, Veronika Weyer-Elberich5, Andrea Laufer3, Toporowski Gregor3, Robert Rödl3, Adrien Frommer3,
1. Danish Pediatric Orthopedic Research, Aarhus University Hospital,
Denmark;
2. Children’s Orthopedics and Reconstruction, Aarhus University Hospital,
Denmark;
3. Pediatric Orthopedics, Deformity Reconstruction and Foot Surgery,
Muenster University Hospital, Germany;
4. General Orthopedics and Tumor Orthopedics, Muenster University
Hospital, Germany;
5. Institute of Biostatistics and Clinical Research, University of Muenster,
Germany
Background: For correction of leg length discrepancy or
angular deformity of the lower limb in
skeletally immature patients temporary or
permanent (hemi-)epiphysiodesis can be
employed. These are reliable treatments
with few complications. Recently,
radiographic analysis of treatment related
alternations of the central knee anatomy
gained interest among pediatric orthopedic
surgeons. To date the comparison and
adequate interpretation of potential changes
of the central knee anatomy is limited due to
the lack of defined standardized
radiographic references.
Aim: The goal of the study is to define new
radiographic refences for the central knee
joint anatomy in skeletally immature
patients.
Materials and Methods: 503 calibrated long standing anteroposterior
radiographs of 254 children aged 8-16 years
with leg length discrepancy < 1 cm and
mechanical axis deviation < 2 cm were
retrospectively analyzed during the study
period (2011-2020). Four specific
radiographic parameters were assessed:
femoral floor angle, tibial roof angle, width of
femoral physis, and femoral notch-
intercondylar distance. Parameters were
analyzed in different age groups (8-10
years, 11-12, 13-14, 15-16) and by sex.
Results: All observed parameters were normally
distributed with a mean age of 12.4 years
(standard deviation (SD) 2, 95% confidence
interval (CI) 12.2 to 12.6). The mean
femoral floor angle was 142° (SD 6, CI 142
to 143), mean tibial roof angle was 144° (SD
5, CI 144 to 145), the mean width at femoral
physis was 73 mm (SD 8, CI 72 to 74) and
mean femoral notch-intercondylar distance
was 8 mm (SD 5, CI 7.5 to 8.3). There were
no clinically relevant age and gender
dependent differences. The estimated
intraclass correlation coefficient values were
excellent for all measurements.
Interpretation / Conclusion: This is the first description of standardized
reference values regarding the central and
sagittal knee joint anatomy in children. We
suggest considering values within the
margin of two standard deviations (SD) as
physiological range. These parameters
might help to identify secondary deformities
during growth modulating treatment such as
epiphysiodesis.
33. Dynamic real-time evaluation of intra- and postoperative cefuroxime tissue concentrations in spine deformity surgery after repeated weight-dosed intravenous administration.
Magnus A. Hvistendahl1,2, Mats Bue1,2,3, Pelle Hanberg1,2, Maiken Stilling1,2,3, Kristian Høy3
1 Aarhus Denmark Microdialysis Research (ADMIRE), Orthopaedic
Research Laboratory, Aarhus University Hospital
2 Department of Clinical Medicine, Aarhus University
3 Department of Orthopaedic Surgery, Aarhus University Hospital
Background: Prophylactic antibiotics are central in
preventing postoperative infections, yet
knowledge on intra- and postoperative spine
tissue concentrations in clinical settings
remains limited. Thus, current antibiotic
prophylactic regimens are based on
empirical knowledge, surrogate measures
(e.g. plasma samples), non-clinical
evidence (experimental models), or inferior
methodology (e.g. tissue specimens).
Aim: The aim was to dynamically investigate
intra- and postoperative cefuroxime spine
tissue concentrations after repeated weight-
dosed administration in patients scheduled
for spine deformity surgery.
Materials and Methods: Twenty patients (15 F, 5 M) were included
(median age (range): 17.5 years (12-74),
mean BMI (range): 22 (16-38), mean
surgery time (range): 4 h 49 min (3 h 57
min-6 h 9 min). Repeated weight-dosed
cefuroxime was administered intravenously
(20 mg/kg) to all patients on average 25 min
before surgery and again 4 hours later.
Microdialysis catheters were placed for
sampling in vertebral bone, paravertebral
muscle, and subcutaneous tissue as soon
as possible after surgery start. Upon wound
closure, the vertebral bone catheter was
removed, and two additional catheters were
placed in the profound and superficial part
of the incision. Microdialysates and plasma
samples were obtained for up to 12 hours.
The primary endpoint was time above the
minimal inhibitory concentration of 4 µg/mL
in percent (%T>MIC 4) of a) patients’
individual surgery time, b) first- and c)
second dosing interval.
Results: Mean %T>MIC 4 (range) of
a) Patients’ individual surgery time was
100% (100-100%) in all investigated
tissues.
b) The first dosing interval was 93% (93-
93%) in vertebral bone, paravertebral
muscle, and subcutaneous tissue, and 99%
(99-100%) in plasma.
c) The second dosing interval was 87% (52-
100%) in paravertebral muscle, 89% (52-
100%) in subcutaneous tissue, 91% (71-
100%) in the profound incision, 94% (72-
100%) in the superficial incision, and 71%
(42-100%) in plasma.
Interpretation / Conclusion: Repeated weight-dosed cefuroxime
administration resulted in sufficient
cefuroxime spine tissue concentrations (>4
µg/mL) both intra- (up to 6 hours) and
postoperative (up to 7.5 hours) in spine
deformity surgery.
34. Functional performance tests, clinical measurements, and patient reported outcome measures are separate outcomes after primary anterior cruciate ligament reconstruction
Mustafa Hamid Hussein Al-Gburi1, Jakob Bredahl Kristiansen2, Karl Bang Christensen3, Michael Rindom Krogsgaard1
1 Section for Sports Traumatology, Department of Orthopedic Surgery, Bispebjerg
and Frederiksberg University Hospital, Copenhagen, Denmark
2 Department of Physical and Occupational Therapy, Bispebjerg and
Frederiksberg University Hospital, Copenhagen, Denmark
3 Section of Biostatistics, Department of Public Health, University of Copenhagen,
Copenhagen, Denmark
Background: The technical results after anterior cruciate
ligament reconstruction (ACLR) are evaluated
by laxity measures, the functional results by
performance tests, and patients’ perception by
patient-reported outcome measures (PROMs). It
is unknown whether one of these can represent
outcome, or if they should all be reported.
Aim: To analyze the correlations between the three
types of outcome one year after primary ACLR.
Materials and Methods: Consecutive adult patients who had an
ACLR between 1.1.2019 and 31.12.2021
were offered a one-year follow-up by an
independent observer. Preoperative
information about laxity, peroperative
information about graft size and pathology of
menisci/cartilage and treatment of this (if
present), and postoperative information
about complications were registered.
At one-year follow-up independent observers
measured clinical and instrumented knee
stability, range of motion, and results of four
different hop tests. Patients completed 4
PROMs (IKDC, KOOS, Lysholm and
KNEES-ACL) and Tegner activity scale,
reported pain scores and answered anchor
questions regarding satisfaction and
willingness to repeat the operation.
Spearman correlations were calculated
between the Lysholm score, IKDC-score,
each domain score in KNEES-ACL and
KOOS and the other outcome modalities.
The strength of the correlations were
interpreted as: 0.00–0.30 negligible, 0.30–
0.50 low, 0.50–0.70 moderate, 0.70–0.90
high and 0.90–1.00 very high
Results: A total of 190 adults attended the one-year
follow-up and 151 had all assessments. There
were only few positive and weak correlations
between performance tests and PROMS and
between clinical measurements and PROMS (r
= 0.00 – 0.38), and the majority were of
negligible strength.
Interpretation / Conclusion: There was no clinically important correlation
between scores obtained by PROMs, a
battery of functional performance tests and
instrumented laxity of the knee at 1-year
follow-up after ACLR, meaning that the
various modalities represent different
aspects of outcome, and that one type of
outcome cannot represent all. This is an
argument for always to include and report all
three types of outcomes, and conclusions
based on one type of outcome may not be
sufficient.
68. The effect of obesity on prosthesis orientation and positioning in patients with hip osteoarthritis following total hip arthroplasty
Hans Christian S. Vistisen1, Mads J. Rex1, Mogens Laursen1, Thomas Jakobsen1
1. Interdisciplinary Orthopaedics, Aalborg University Hospital
Background: In total hip arthroplasty (THA), orientation of
prosthesis components is of the utmost
importance regarding hip stability, component
wear and failure rates. In literature, obesity has
been related to increased leg length
discrepancy (LLD) and poorer placement of the
acetabular component as well as increased risk
of dislocation.
Aim: The aim of this study was to investigate the
effect of obesity on prosthesis component
orientation and positioning in hip osteoarthritis
patients operated with THA.
Materials and Methods: A retrospective observational study on 614
THAs at Farsoe Hospital in the period 2015-
2022, distributed in an obese (BMI >35) and a
reference group (BMI 20-25). Pre- and
postoperative x-rays were assessed for cup
positioning and orientation, stem alignment and
LLD according to standards in the TraumaCad
software. Cup orientation was tried in safe
zones of; +/-15 and +/-5 degrees from the
optimal orientation suggested by literature.
Crude and adjusted multiple linear regression
models were used to detect statistically
significant differences between the two groups.
Results: In the reference group, 58.5% of cups were
within the Lewinnek safe zone versus 53.8% in
the obese group. Adjusted linear regression
models proved significantly lower odds ratio for
the cup to be within the +/-5 safe zone in the
obese group (0.61, p-value = 0.003), while there
was no difference in the +/-15 safe zone (0.97,
p-value =0.89). The obese group had
significantly lesser anteversion (-4.04, p-
value<0.001) and greater inclination of the cup
(2.60, p-value = 0.0014). Furthermore, the
obese group had a greater increase in lateral
offset (1.76, p-value=0.016). There was no
difference in stem alignment or LLD. Mean LLD
was 5.8 mm with a SD of 4.5 mm in the obese
group and 5.6 mm with a SD of 4.6 mm in the
reference group.
Interpretation / Conclusion: This study found a lesser percentage of
acetabular components inside the Lewinnek
safe zone in the obese group. In the adjusted
models, the obese group had a significantly
lower odds ratio for the cup being in the +/-5
safe zone for cup orientation. The obese group
had a significantly greater increase in lateral
offset. There was no difference in stem
alignment or LLD.
36. Computer-assisted intramedullary nailing of intertrochanteric fractures failed to improve the tip-apex distance and lag screw protrusion
Rasmus Holm Hansen, Jan Duedal Rölfing, Christian Lind Nielsen, Ole Brink, Per Hviid Gundtoft
Department of Orthopaedics, Aarhus University Hospital
Background: Intertrochanteric femoral fractures are
commonly treated with intramedullary nails
(IMN). A common complication of this treatment
is lag screw cut-out. A tip-apex distance (TAD) of
more than 20-25 mm is associated with an
increased risk of cut-out. The Stryker ADAPT
system is a computer-assisted navigation
system, which has been reported to decrease
the TAD.
Aim: To prospectively assess if ADAPT decreases the
TAD and lag screw protrusion after
implementation in our department.
Materials and Methods: All patients with intertrochanteric fractures
treated with an IMN were prospectively included
between 1 September 2020 and 12 March 2022.
The cohort was divided in three periods: 54
patients operated before ADAPT implementation
(pre-ADAPT), 50 patients with ADAPT during its
implementation (ADAPT-period), and 59 patients
without ADAPT after we discontinued its use
(post-ADAPT). The TAD and lag screw
protrusion beyond the lateral cortex were
manually measured in accordance with
previously published studies of TAD.
Results: The median TAD in the three periods were 17.0
mm (8-31), 15.5 mm (9-30), and 18.0 mm (11-
32) respectively. Thus, we found no statistically
nor clinically relevant reduction of the TAD when
using ADAPT compared with the pre-ADAPT
period (p=0.62). In the pre-ADAPT period, 14
out of 54 patients had a TAD > 20 mm, while 10
out of 50 patients had a TAD >20 during the
ADAPT-period. Importantly, ADAPT failed to
reduce the number of outliers with TAD >20 mm
(p=0.23) and TAD >25 mm (p=0.43, Chi-square
test). Moreover, ADAPT did not significantly
reduce the protrusion of the lag screw beyond
the lateral cortex in the ADAPT period compared
to the pre- and post-ADAPT periods.
Interpretation / Conclusion: ADAPT did not improve the TAD or lag screw
protrusion during implementation. Importantly, it
did not reduce the number of outliers and was
thus discontinued at our department. We found
no benefit to using the ADAPT system.