Tumors
69. Physical function is reduced and correlated to quality of life after limb-sparing surgery due to bone sarcoma
Linda Fernandes, Kreutzfeldt Zebis Mette, Michala Skovlund Sørensen , Christina Enciso Holm , Allan Villadsen , Michael Mørk Peteresen
Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet and University College Copenhagen ; Department of Midwifery, Physiotherapy, Occupational Therapy and Psychomotor Therapy, University College Copenhagen; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet
Background: Patients with bone sarcoma report that quality of life
(QoL) is affected years after treatment. In
rehabilitation, both QoL and different measures of
physical function are assessed and targeted.
However, few studies have investigated physical
function and its relationship to QoL in this patient
group.
Purpose / Aim of Study: The purpose was to investigate if physical function in
patients with bone sarcoma receiving limb-sparing
surgery (LSS) and reconstruction with a tumour-
prosthesis was affected and associated with QoL.
Materials and Methods: Thirty patients operated (proximal femur (n=12),
distal femur (n=14), proximal tibia (n=4))
between 2006 and 2016 were compared to 30
healthy controls in a cross-sectional design.
Differences between groups were tested for
objectively measured physical function: isometric
muscle strength in gluteus medius and
quadriceps, six-minute walk test (6MWT) and
30s sit-to-stand test (STS). In the patient group,
measures of physical function were correlated
with EORTC QLQ-C30 Global Health (GH),
Physical functioning (PF) and Role functioning
(RF) subscales. Paired samples t-test was used
for analyses of between group differences and
Spearman’s rank correlation for associations
within the patient group.
Findings / Results: Mean age of participants was 51 years and mean
BMI 26. Significant (statistical and clinical)
differences were found for all muscle strength tests
between the two groups, both for comparisons of the
leg that underwent surgery and the contralateral leg.
Significant differences were also seen for the 6MWT
(499 vs. 607 m, p<0.001) and the STS (12 vs. 18,
p<0.001). Physical function was correlated to QoL
when comparing muscle strength of gluteus medius
with GH (rho 0.43, p=0.019) and with PF (rho 0.51,
p=0.006), and quadriceps strength with PF (rho
0.40, p=0.034) and with RF (rho 0.40, p=0.038).
Conclusions: Patients with bone sarcoma receiving LSS and
reconstruction with a tumour-prosthesis showed
deficits in muscle strength, 6MWT and STS when
compared to controls. Decreased strength of gluteus
medius and quadriceps muscles correlated to QoL
subscales, indicating that strength training could be
a potential factor for improving physical components
of QoL.
70. Surgical Treatment of Proximal Femoral Metastases: A Systematic Review and Meta-Analysis of Reoperations and Implant Failures
Mads Sten Andersen, Michala Skovlund Sørensen, Michael Mørk Petersen
Orthopedic surgery, Rigshospitalet; Orthopedic surgery, Rigshospitalet; Orthopedic surgery, Rigshospitalet
Background: The continuous improvements in survival of
cancer patients increases the prevalence of
metastatic bone disease, while also altering
the demands for the durability of the
surgical implants used. In the appendicular
skeleton the metastatic lesions requiring
surgery are most often located in the
proximal femur, and are currently treated
with either open reduction and internal
fixation (ORIF), intramedullary nailing (IMN)
or endoprosthetic reconstruction (EPR).
Purpose / Aim of Study: To investigate whether there is a difference
in reoperation or implant failure rates
between the currently used methods of
surgical treatment of metastatic bone
disease of the proximal femur.
Materials and Methods: The literature was systematically reviewed
through a PubMed search in order to
identify studies concerning surgical
treatment of proximal femur metastases in
the period 01.01.2009-04.01.2020. The
primary outcome measure was reoperation
rate, while implant failure rate was
registered as the secondary outcome
measure. Eighteen studies, with a total of
2489 patients, were included for analysis, all
retrospective and non-randomized. In a
meta-analysis pooled estimates for the
odds-ratios (OR) between treatments
regarding both reoperation and implant
failure were calculated with 95 %
confidence intervals (CI).
Findings / Results: Meta-analysis showed more patients treated
with ORIF needed further surgery, with the
pooled OR estimate being 3.07 (95% CI:
1.98-4.76, p<0.001) for reoperation and
8.47 (95% CI: 5.05-14.21, p<0.001) for
implant failure compared to EPR. No
difference was found when comparing
reoperation after IMN to EPR (OR = 1.04
(95% CI: 0.77-1.42, p=0.79)), but the
analysis showed a higher risk of implant
failure after IMN with an OR of 2.65 (95%
CI: 1.74-4.02, p<0.001).
Conclusions: The higher reoperation rate found in
patients treated with ORIF, suggests that
this method of treating proximal femur
metastases should be considered obsolete.
Analysis of implant failure further indicates,
that EPR provides a more mechanically
stable solution compared to IMN. The
mediocre evidence that the included studies
provide calls for further research reporting
time-adjusted reoperation rates, allowing for
more optimal comparison of methods
between studies.
71. Development and comparison of one-year survival models in patients with primary bone sarcomas - External validation of a Bayesian belief network model and creation and external validation of a new Gradient Boosting Machine model.
Christina Holm, Clare f. Grazal, Mathias Raedkjaer, Thomas Baad-Hansen, Rajpal Nandra, Robert Grimer, Jonathan A. Forsberg, Michael Mørk Petersen, Michala Skovlund Sørensen
Orthopedic surgery, Rigshospitalet; Orthopaedics , USU-Walter Reed Department of Surgery, Bethesda, MD, USA; Department of Orthopaedic Surgery, Aarhus University Hospital, Denmark; Department of Orthopaedic Surgery, Aarhus University Hospital, Denmark; Orthopedic, The Royal Orthopaedic Hospital, Birmingham, UK; Orthopedic, The Royal Orthopaedic Hospital, Birmingham, UK; Orthopaedics , USU-Walter Reed Department of Surgery, Bethesda, MD, USA; Orthopedic surgery, Rigshospitalet; Orthopedic surgery, Rigshospitalet
Background: Bone sarcomas often presents late with advanced
stage at diagnosis, resulting in varying short-term
survival. In 2016 Nandra et al., generated a
Bayesian belief network model (BBN) for 1-year
survival of patients with bone sarcomas.
Purpose / Aim of Study: The purpose of present study is to: 1) External
validate the prior 1-year BBN prediction model for
survival of patients with bone sarcomas, 2) To
develop a Gradient Boosting machine (GBM) model
using Nandra et al.’s cohort and evaluate if the GBM
model outperform the BBN model suggested by
Nandra et al. when externally validated on an
independent Danish population cohort.
Materials and Methods: The training cohort comprised 3493 patients newly
diagnosed with bone sarcoma from the institutional
prospectively maintained database at The Royal
Orthopaedic Hospital, Birmingham UK. The
validation cohort comprised 771 patients with newly
diagnosed bone sarcoma included from The Danish
Sarcoma Registry between January 1st, 2000 and
June 22sd, 2016. Predictive performance of models
was evaluated by area under receiver operator
characteristic curve (AUC ROC) analysis, Brier
score and decision curve analysis (DCA).
Findings / Results: External validation of the BBN 1-year prediction
model demonstrated AUC ROC of 68% (95%CI,
62%-73%). AUC ROC of the GBM model
demonstrated 75% (95%CI: 70%-80%), overall
model performance by Brier score was 0.09 (95%CI:
0.077-0.11) and DCA demonstrated a positive net-
benefit for threshold probabilities above 0.5. External
validation of the developed GBM model
demonstrated AUC ROC of 63% (95%CI: 57%-68%)
and the Brier score was 0.14 (95%CI: 0.12-0.16).
Conclusions: External validation of the 1-year Bayesian belief
network survival model yielded poor outcome and is
hence not recommendable for clinical usage. The
developed Gradient Boosting Machine 1-year
survival model did not outperform the prior Bayesian
belief network model, and modernization is pending.
72. Work ability and physical activities in patients with tumour prosthesis in hip or knee following bone sarcoma. A cross-sectional study comparing patients with healthy controls.
Linda Fernandes, Mette Kreutzfeldt Zebis, Allan Villadsen, Christina Encisio Holm, Michala Skovlund Sørensen, Lars L Andersen, Michael Mørk Peteresen
Faculty of Health and Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, University College Copenhagen and Rigshospitalet; Faculty of Health, University College Copenhagen; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet; , National Research Centre for the Working Environment; Musculoskeletal Tumour Section, Department of Orthopaedic Surgery, Rigshospitalet
Background: While most patients going through limb-sparing
surgery (LSS) due to bone sarcoma are of the
working-age population, limited knowledge exist
about their work ability.
Purpose / Aim of Study: The study aim was to assess work ability and
physical activity (PA) in these patients.
Materials and Methods: This cross-sectional study compared employed
patients, receiving LSS and reconstruction in
proximal (n=9) or distal femur (n=7) or proximal
tibia (n=4) between 2006 and 2016, with
employed healthy controls (n=20). The
Musculoskeletal Tumour Society Score (MSTS)
was used as descriptive information. The Work
Ability Index (WAI), financial difficulties, the
Patient Specific Functional Scale (PSFS), activity
monitor and the International Physical Activity
Questionnaire (IPAQ) were used to evaluate
work ability and physical activities. Between
group differences were assessed using
unadjusted and adjusted (sex, age, BMI,
educational level, type of work) general linear
models.
Findings / Results: The patients were seen on average 7 (±2.9) years
post-surgery, had a mean age of 43 (±13.6) years,
BMI 27 (±3.7) and MSTS of 69 (±14.6)%. Six
patients (30%) experienced that their physical
condition had caused financial difficulties. The
adjusted analyses showed differences in general
work ability (7.8 vs. 9.1 points, p=0.002) and work
ability due to physical demands (3.2 vs. 4.6 points,
p<0.001) between patients and controls. There were
between group differences in PSFS mean score (2.8
vs. 9.5 points, p<0.001). No differences were seen in
step counts/day (10588 vs. 12239 steps, p=0.144)
or the IPAQ (4107 vs. 4035 METs/week, p=0.942).
Conclusions: Most patients experienced difficulties in performing
tasks requiring physical demands at work.
Furthermore, 1/3 reported financial difficulties
caused by their condition. Although we found no
differences in PA, patients reported great difficulties
in performing activities that they scored as
important. Assessments of work demands and
collaboration with workplaces should be considered
in rehabilitation following LSS and reconstruction
with tumour prosthesis.
73. Quantitative measurements of adaptive bone remodeling around the Cemented Zimmer® Segmental stem after tumor resection arthroplasty using dual-energy X-ray absorptiometry
Christina Holm, Peter Horstmann, Michala Skovlund Sørensen, Karen Dyreborg, and Michael Mørk Petersen
Musculoskeletal Tumor Section, Department of Orthopedic Surgery, Rigshospitalet, University of Copenhagen, Denmark
Background: Limb salvage surgery is currently offered to more
than 90% of patients with bone or soft tissue
sarcomas and to a greater extent also to patients
with metastatic bone disease.
Purpose / Aim of Study: The aim of the present study was to evaluate the
adaptive remodeling of the periprosthetic cortical
bone after insertion of a tumor prosthesis with a
cemented stem.
Materials and Methods: A prospective study of 21 patients (F/M=12/9),
mean age 55 years (range 15-81) with metastatic
bone disease (n=9), sarcomas (n=8) or
aggressive benign tumors (n=4) who underwent
bone tumor resection and reconstruction with a
tumor prosthesis (Zimmer® Segmental 130 mm
straight fluted cemented stem with trabecular
metal (TM) collars) in the proximal femur (n=10),
distal femur (n=9) or proximal tibia (n=2) .
Measurements of bone mineral density (BMD)
were done postoperatively and after 3, 6, and 12
months of the periprosthetic bone and in both
ankles by using dual-energy X-ray
absorptiometry. BMD (/g/cm2) was measured in
4 regions of interest around the cemented stem
and in one region of interest 1 cm proximal from
the ankle joint. Repeated measures ANOVA and
students paired t-test was used to evaluate BMD
changes over time
Findings / Results: At 1-year follow-up, BMD compared to the
postoperative value was seen in all 4 regions of
interest with a statistically significant bone loss of 8-
15%. The bone loss was most pronounced (14-15%)
in the 2 regions of interest closest to the TM collar
and lowest (8%) adjacent to the tip of the stem. After
1 year the decrease in BMD of the ankle on the
affected extremity was 9% and the ankle on the
contralateral extremity was close to baseline.
Conclusions: The periprosthetic BMD around the cemented 130
mm Segmental stem decreased significantly during
the first postoperative year and is considered
caused by a combination of stress shielding and
immobilization.
74. Reconstruction of the humerus using the Comprehensive Segmental Revision System in patients suffering from metastatic bone disease.
Claus Lindkær Jensen, Michala Skovlund Sørensen, Michael Mørk Petersen
Musculoskeletal Tumor Section, Department of Orthopedics, Rigshospitalet, University of Copenhagen; Musculoskeletal Tumor Section, Department of Orthopedics, Rigshospitalet, University of Copenhagen; Musculoskeletal Tumor Section, Department of Orthopedics, Rigshospitalet, University of Copenhagen
Background: Surgical treatment of malignant bone
tumors of the humerus is often
followed by reconstruction with a tumor
prosthesis. The Comprehensive
Segmental Revision System® (Zimmer-Biomet, Warsaw, IN, USA) (SRS) offers a new option for such reconstructions.
Biomet, Warsaw, IN, USA) (SRS)
offers a new option for such
reconstructions.
Purpose / Aim of Study: The aim og this study was to evaluate
implant failure incidence, surgical
complications, and clinical results.
Materials and Methods: A study of 22 consecutive patients
(F/M= 9/13, mean age = 67 (51-83)
years) suffering from metastatic bone
disease having surgery with bone
resection of the humerus (18 proximal
humerus replacements
(hemiarthroplasty/total-reverse joint = 4
4/14) and 4 distal humerus r
replacements) and reconstruction u
using the SRS prosthesis from May 2
2014 to January 2017.
Statistics: Kaplan-Meier survival
analysis (patient survival) and Aalen-Johansson estimate (incidence of implant failure) presented with 95%
Johansson estimate (incidence of
implant failure) presented with 95%-
-confidence intervals (CI). Results are g
given as mean (range).
Findings / Results: Two-year overall patient survival was
41% (CI: 20-62%). Five patients
suffered from surgical complications:
radial nerve palsy (n=2) and superficial
postoperative infection (n=3). Two
patients experienced revision surgery:
soft tissue revision (n=1) and a
hemiarthroplasty revised to a reverse
total shoulder replacement (n=1). Two-year implant failure incidence was 5% (CI:0
year implant failure incidence was 5%
(CI:0-13%). The mean MSTS score
(n=6) was 16 (11-25), 221 (95-360)
days postoperatively.
Conclusions: The use of the SRS prosthesis in
orthopedic oncology patients resulted
in low incidence of implant failure.
Since the introduction of the SRS
prosthesis in our department
represented at shift from using
hemiarthroplasty to prefer total-reverse
joint implants, the fact that we
observed no shoulder dislocations was
a positive short-term result.
75. Ewing´s sarcoma of the calcaneus treated by limb sparing surgery with calcanectomy and reconstruction with a composite of an allograft and a vascularized osteocutaneous fibula graft.
Michael Mørk Petersen, Lisa Toft Jensen, Christian Bonde, Werner Herbert Hettwer
Department of Orthopedics (Musculoskeletal Tumor Section), Rigshospitalet, University of Copenhagen, Denmark; Department of Plastic Surgery, Rigshospitalet, University of Copenhagen, Denmark; Department of Plastic Surgery, Rigshospitalet, University of Copenhagen, Denmark; Department of Orthopedics (Musculoskeletal Tumor Section), Rigshospitalet, University of Copenhagen, Denmark
Background: Primary malignant bone tumors of the calcaneus are
very seldom, and due to poor possibilities to do
surgery with wide margins in this region and limited
options for reconstruction after calcanectomy many
orthopedic oncologists use amputation as the
preferred surgical treatment in such cases.
Purpose / Aim of Study: We present two cases of Ewing´s sarcoma of the
calcaneus treated with calcanectomy and
reconstruction with a composite of an allograft and a
vascularized osteocutaneous fibula graft.
Materials and Methods: The medial cases of 2 girls suffering from Ewing´s
sarcoma of the calcaneus that were almost 6 years
old (case 1) and 16 years old (case 2) at the time of
surgical treatment with calcanectomy in respectively
August 2012 and October 2013 are presented. Both
patients were without metastatic disease and
received pre- and post-operative chemotherapy.
Findings / Results: In both cases removal of the calcaneus was performed using a combined
medial and lateral incision. In case 1 a femoral head allograft was fitted to
replace the removed calcaneus, and in case 2 a calcaneus allograft was
used. In both cases, with the aim of obtaining arthrodesis, the allograft was
fixed to the talus and cuboid bone with screws. A distally pedicled
osteocutaneous flap was use for reconstruction of soft tissue, and a 5-6 cm
piece of vascularized fibula bone was fitted into the allograft and fixed using
staples. Arthrodesis between talus and the graft healed and full weight-
bearing was allowed in both cases 8-9 months postoperatively. At follow-up
6½ and 4½ years after surgery both patients were without local recurrence or
metastases, and they were both pain-free and able to walk using normal
footwear without any walking-aids.
Conclusions: Biological reconstruction is possible after removal of
the calcaneus because of primary malignant bone
tumors and long-term good functional results can be
achieved.