Session 3: Trauma I

Ondag den 26. oktober
09:00 – 10:30
Lokale: Helsinki/Oslo
Chairmen: Nanna Salling / Michael Brix

23. Reoperation after long and short intra medullary nail in patients with per- and subtrochanteric fracture.
Lasse Eriksen, Frederik Højsager, Katia Damsgaard Bomholt, Søren Overgaard, Jens Lauritsen, Bjarke Viberg
Department of Clinical Research, University of Southern Denmark, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Research, University of Southern Denmark, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Research, University of Southern Denmark, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Research, University of Southern Denmark, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Research, University of Southern Denmark, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Research, University of Southern Denmark, Department of Orthopaedic Surgery and Traumatology, Odense University Hospital


Background: Short (SIMN) and long Intramedullary Nails (LIMN) are frequently used in the management of femoral pertrochanteric (Pfx) and subtrochanteric fractures (Sfx) but the literature is scarce on the optimal choice regarding reoperations. The motivation for use of LIMN in Pfx has been prophylaxis for new fractures distal to a short nail.
Purpose / Aim of Study: To compare reoperation proportions between SIMN and LIMN in patients with Pfx and Sfx.
Materials and Methods: From 2008–2013 data on 8.516 hip fractures in the Region of Southern Denmark was retrieved from the Danish Multidisciplinary Registry for Hip Fractures (DMRHF). 1.419 patients with the procedure codes KNFJ51-52 were included. Data from DMRHF includes age, sex, Charlsons Comorbidity Index (CCI), and reoperations within 2 years. All health records were reviewed for type of IMN and fracture near the IMN (fxIMN). Proportions of reoperation and crude and age/sex/CCI adjusted Odds Ratios (OR) from logistic regression comparing SIMN and LIMN are given with 95% Confidence intervals.
Findings / Results: There were 807 patients with Pfx and 612 with Sfx. The median age was 84.8 years and 70.6% were female with no differences between groups. Pfx reoperation level for SIMN was 5.6% (3.7;8.0) (27/483 – 3 fxIMN) compared to 8.0% (5.3;11.5) (26/324 – 4 fxIMN) for LIMNs. Crude OR = 1.47 (0.84;2.57), adjusted OR = 1.56 (0.89;2.74) comparing LIMN to SIMN. Sfx reoperation level for SIMN was 10.8% (7.0;15.8) (23/213 – 5 fxIMN) compared to 6.0% (3.9;8.8) (24/399 – 2 fxIMN) for LIMN. Crude OR = 0.52 (0.29;0.96), adjusted OR =0.49 (0.26;0.9) comparing LIMN to SIMN.
Conclusions: This is the largest study to date showing no difference between SIMN and LIMN for Pfx but an increased risk of reoperation for Sfx managed with SIMNs. Thus there seems to be no indication for use of long nails in Pfx as a routine.

24. Reoperations after cemented and uncemented hemiarthroplasty - A study from the Danish Multidisciplinary Registry of Hip Fractures (DMRHF)
Bjarke Viberg, Alma Becic Pedersen, Anders Kjærsgaard, Jens Lauritsen, Søren Overgaard
Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Epidemiology, Aarhus University Hospital; Department of Clinical Epidemiology, Aarhus University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital


Background: Cemented hemiarthroplasty (cemHA) has in several nationwide registries shown to be superior to uncemented hemiarthroplasty (uncemHA) in regards to reoperation, but still the uncemented is used in a number of countries.
Purpose / Aim of Study: To compare the reoperations for cemHA vs uncemHA in hip fracture patients with up to 5 years’ follow-up.
Materials and Methods: This is a population based register study with data from DMRHF and the Danish National Registry of Patients. Data was retrieved from 01.01.2004 to 12.31.2013 with a minimum of 2 years’ follow-up on procedure codes (NFB02, NFB12), age, sex, Charlson Comorbidity Index (CCI), reoperation status and vital status. Among 70,652 hip fractures in total, 16.741 have had a HA. Reoperation was defined as dislocations, periprostethic fractures, deep infections and other reasons, and were based on data reported to DNRP.
Findings / Results: There were 8513 uncemHA and 8228 cemHA with no difference between median age (quartiles) of 84.2 (79.1-88.7) for uncemHA and 83.8 (78.5-88.5) for cemHA, respectively. There were 76 % females in both groups and the median follow-up was 3.5 years. The reoperation percentage was 4.6 % for uncemHA and 3.4 % for cemHA. A crude Cox-regression analysis using Hazard Ratio (HR) with 95 % CI for uncemHA compared to cemHA yielded 0.72 (0.62;0.84) after 1 year, 0.76 (0.63;0.91) from 1-2 years, and 0.68 (0.56;0.82) from 2-5 years. When adjusting for age, sex, and CCI the HR was 0.72 (0.62;0.84) after 1 year, 0.75 (0.63:0.90) from 1-2 years, and 0.68 (0.56;0.82) from 2-5 years. Higher age seems to be a protective factor.
Conclusions: CemHA has an overall lower reoperation percentage compared to ucemHA and this nationwide study from DK suggest that patients with femoral neck fractures should be treated with a cemHA rather than a uncemHA.

25. Exploring learning curves for simulation-based hip-fracture surgery
Amandus Gustafsson, Poul Pedersen, Henrik Palm, Lars Konge
Copenhagen Academy for Medical Education and Simulation, The Capital Region of Denmark; Department of Orthopedics, Copenhagen University Hospital Hvidovre; Hip Fracture Unit, Department of Orthopedics, Copenhagen University Hospital Hvidovre; Copenhagen Academy for Medical Education and Simulation, The Capital Region of Denmark


Background: Inexperienced orthopedic interns can contribute to a higher reoperation rate in hip fracture surgery. Computer-simulation has improved operative skills in other surgical specialties and mandatory training to proficiency on a hip fracture surgery simulator should be considered for orthopedic interns.
Purpose / Aim of Study: The aims of this study were to explore how much simulation training orthopedic interns need for reaching the plateau phase of their learning curve and to define a pass/fail standard for mastery learning based on the level of the plateaus.
Materials and Methods: Sixteen orthopedic interns were included for simulation with cannulated screws, Hansson Pins and Sliding Hip Screw on the Swemac TraumaVision, which has a scoring system with validity evidence. The scores as a percentage of maximum for the three procedures were combined to one average total score. The training ceased when an intern failed to improve the total score for three consecutive times.
Findings / Results: The orthopedic interns practiced the three procedures eight to 18 times, average 179 minutes (110-246 minutes). Participants improved significantly and performed more consistently after training, initial score = 71.2 (SD 11.0) and maximum score = 94.5 (SD 4.0). Maximum score above 90 points was achieved after a mean of 145 minutes (59-241 minutes). There was a significant correlation between the initial score and the maximum score (Pearson’s r=0.51, p=0.046).
Conclusions: Performance improved for all, but with large variations in the individual progression and the initial performance to some degree predicting the max score. There was no correlation between the time spend practicing and the maximum score, but all interns except one could achieve a max score above 90, which we suggest as a pass standard in a formal mastery learning simulation program.

26. Dementia as risk factor of Corail stem dislocation
Bjørn Nedergaard, Ahsan Al-Maleh
Orthopaedic , OUH/Svendborg; Orthopaedic, OUH/Svendborg


Background: Dementia is a neurologic disorder causing cognitive impairment. The prevalence in Denmark is 80.000 and concern has been raised as to whether these patients have an increased risk of hip hemiarthroplasty dislocation.
Purpose / Aim of Study: To determine if dementia is a risk factor of dislocation of Corail stem and Ultima caput.
Materials and Methods: Retrospective evaluation of patients operated from 01.01.2007 to 31.12.2010 at Svendborg Hospital. Inclusion criteria: Operation code KNFB02 (primary operation with uncemented distal component of hip hemiarthroplasty). Exclusion criteria: Death or reoperation within the first year (both unless the arthroplasty has dislocated first) or dementia state unknown. After surgery patients were admitted to the geriatric ward and evaluated by the staff during rehabilitation. If suspicion of cognitive impairment arose, the patients were assessed at the geriatric out-patient clinic 3 months post-discharge and potentially diagnosed with dementia. We evaluated patient files for dementia (DF00, DF01, DF03) and dislocation of arthroplasty up to 1 year after the initial operation.
Findings / Results: 319 patients met the inclusion criteria. 92 were excluded (49 died < 1 year, 2 were reoperated < 1 year, 41 were lost before geriatric evaluation). 227 patients (71%) were included of which 68 (30%) had dementia and 159 (70%) did not. 10 (14%) of the patients with dementia dislocated their arthroplasty within the first year vs. 6 (3%) of the patients without dementia resulting in an OR for dislocation (dementia vs. no dementia): 4,3 [95% CI 1,53 – 12,64]. There was no difference in age (dementia vs. no dementia) p=0,81, and no difference in age (+dislocation vs. – dislocation) p=0,75.
Conclusions: Patients with dementia have 4,3 times higher risk of dislocating their hip hemiarthroplasty vs. patients without dementia.

27. Management of hip fractures in Denmark: a questionnaire
Peter Hedelund Rabøl
Department of Orthopedics, Odense University Hospital


Background: Management of hip fractures (HipFx) are part of the daily activities in most orthopaedic departments. The typical patient is geriatric with several co-morbidities. Post-operative mortality remains high and reoperations are frequent. In 2008 the Danish Orthopaedic Society published updated management guidelines for HipFx patients to help standardize treatment according to best evidence.
Purpose / Aim of Study: We sought to investigate to which extent the guidelines are used today in the Danish orthopaedic departments treating HipFx. Our focuses were surgeon experience and supervision, fracture classification and implant selection, co-work with geriatricians and out-patient follow-up.
Materials and Methods: We composed an online questionnaire distributed to all 24 Danish orthopaedic departments treating HipFx. The response rate was 100%. 2 departments declined due to very low frequency of HipFxs.
Findings / Results: In 13 of the 22 departments, HipFxs were primarily treated by junior surgeons. Rate of supervision varied and 10 departments had no formalized operative training. 10 co-worked with Geriatricians and only 5 provided out-patient follow-up. 16 used surgical algorithms for choice of implant, which to some extent appeared in accordance with the Danish Orthopaedic Society guidelines.
Conclusions: The parts of the Danish Orthopaedic Society guidelines covered in this study were widely used across the country. However, HipFxs were primarily operated by junior surgeons, with several departments lacking formalized training and supervision. Also less than half of departments co-worked with Geriatricians. In our opinion, these aspects need focus for further optimizing the HipFx treatment in Denmark.

28. Thrombosis after hip fracture surgery
Liv Riisager Wahlsten, Henrik Palm, Jonas Olesen, Gunnar Gislason, Stig Brorson
Department of Orthopaedics, Copenhagen University Hospital Herlev; Hip Fracture Unit, Department of Orthopaedics, Copenhagen University Hospital Hvidovre; Cardiovascular Research Center, Copenhagen University Hospital Gentofte; Cardiovascular Research Center, Copenhagen University Hospital Gentofte; Department of Orthopaedics, Copenhagen University Hospital Herlev


Background: Thromboembolism is a serious complication after hip fracture surgery. Antithrombotic prophylaxis guidelines have been debated and based on literature now recommend treatment 10 days post-op for all hip fracture patients. If thrombosis risk factors are identified, future antithrombotic prophylaxis guidelines could however be individualized.
Purpose / Aim of Study: To determine event rates, temporal patterns, and risk factors of clinical significant thromboembolic complications after hip fracture surgery; including venous thromboembolism (VTE), myocardial infarction (MI), stroke, and all-cause mortality.
Materials and Methods: All Danish citizens aged ≥50 years surviving until discharge after surgery for hip fractures between 1999 and 2012 were included in this national cohort study. Data was obtained from the national administrative databases. Cox regression models were used to identify covariates associated with an event.
Findings / Results: We included 98,212 patients surviving surgery for a hip fracture. During 1-year of follow-up, VTE occurred in 1.66%, MI in 1.92%, and stroke in 4.03%, mortality was 29%. The event rate was highest in the beginning of the follow-up period, and the median time to an event was 28 days for VTE, 11 days for MI, and 22 days for stroke. The strongest risk factor of any thromboembolic complication was having a previous history of the event, leading to hazard ratios at 3.6 (CI 2.8-4.5) for previous VTE, 7.5 (CI 7.1-8.0) for previous MI, and 4.9 (CI 4.4-5.4) for previous stroke.
Conclusions: Thromboembolism seems to occur early after hip fracture surgery. Also it appears possible to identify patients at high risk, which indicates the possibility of future more individualized antithrombotic prophylaxis guidelines.

29. 35-year trends in first-time hospitalization for hip fracture and one year mortality: a Danish nationwide cohort study, 1980-2014
Alma B Pedersen, Vera Ehrenstein, Szimonetta Szepligeti, Astrid Lunde, Ylva T Lagerros, Anna Westerlund, Grethe S Tell, Henrik Toft Sørense
of Clinical Epidemiology, Aarhus University Hospital; of Clinical Epidemiology, Aarhus University Hospital; of Clinical Epidemiology, Aarhus University Hospital; of Global Public Health and Primary Care, University of Bergen; of Clinical Epidemiology, Karolinska Institutet; Centre of Pharmaoepidemiology, Karolinska Institutet; of Global Public Health and Primary Care, University of Bergen; of Clinical Epidemiology, Aarhus University Hospital


Background: Osteoporosis affects 200 million persons worldwide, with hip fracture being the most common manifestation of the disease.
Purpose / Aim of Study: To examine trends in hip fracture incidence in Denmark from 1980 to 2014, and trends in subsequent one-year mortality by sex, age, and comorbidity.
Materials and Methods: Nationwide cohort study based on prospectively collected Danish registries. Participants: 262,437 patients with incident hip fracture. Outcomes: Standardized incidence rate of hip fracture; mortality 30 days and 31-365 days after hip fracture. Comorbidity was assessed using the Charlson Comorbidity Index (CCI) score. We computed mortality rate ratios (MRRs) using Cox regression.
Findings / Results: Despite slight increases in incidence rates of hip fracture up to the mid-1990s, the incidence rate decreased by 29% from 1980 to 2014 in women, but remained stable in men. Rates decreased in persons of all age groups. The proportion of patients with very severe comorbidity preceding hip fracture increased from 5.6% in 1980-1984 to 26.5% in 2010-2014, respectively. Adjusted MRRs were 0.7 (95% confidence interval (CI): 0.6-0.7) within 30 days and 0.6 (95% CI: 0.6-0.7) within 31-365 days of hip fracture in 2010-2014 compared with 1980-1984. Analyses stratified by CCI revealed a reduction in mortality from 1980 to 2014 both in patients without comorbidity and in patients with different scores of comorbidity.
Conclusions: We found a decrease in rates of hip fracture in women, and in all age groups from 1980 through 2014. Although the proportion of patients with comorbidity increased twofold to fivefold over time, 30-day and 31-365 day mortality decreased by 30% to 40% over the study period. The decrease in mortality was seen in patients without and with comorbidity before hip fracture across calendar periods of hip fracture diagnosis.

30. Can trauma surgeon’s subjective intraoperative conclusions on patients bone quality be trusted?
Ole Brink, Tei Randi, Langdahl Bente
Orthopaedic Surgery - Traumatology, Aarhus University Hospital ; Department of Endocrinology and Internal Medicine , Aarhus University Hospital ; Department of Endocrinology and Internal Medicine , Aarhus University Hospital


Background: How are my bones, do I have osteoporosis? Orthopedic surgeons are occasionally asked this question, but how valid is the surgeons answer?
Purpose / Aim of Study: The purpose of this study was to validate trauma surgeon’s estimation of bone quality and conclusions whether a patient undergoing fracture surgery has osteoporosis or not.
Materials and Methods: Trauma surgeons were asked to evaluate the quality of the bone on a 10 cm visual analogue scale (VAS) ranging from very poor to extremely high bone quality. The surgeons also concluded “osteoporosis”, “not osteoporosis” or “not able to answer”. Within three months after surgery all patients were invited to a dual x-ray absorptiometry (DXA) for measuring bone mineral density. ROC curves were used as diagnostic tools to describe the accuracy of VAS score against DXA. Nonparametric methods were used to calculate area under the ROC curves.
Findings / Results: Fifty-three patients were included. Area under the ROC curve measuring accuracy of VAS as diagnostics tool for osteoporosis was 0.698 and for diagnosing a status of osteopenia or osteoporosis the area was 0.727. Using a cut point on the VAS scale 4 cm or less as diagnostics for osteoporosis the sensitivity was 84%, the specificity 42% and 75% were correctly classified. Using the same cut point of 4 cm for diagnosing osteopenia or osteoporosis from the VAS scale the sensitivity was 93%, specificity 27% and 45% were correctly classified. The positive predictive value of the surgeons’ conclusion of osteoporosis was 50% and the negative predictive value was 83%. If surgeons’ conclusion of osteoporosis was used as a surrogate for any abnormal low bone density (osteopenia or osteoporosis) the positive predictive value raised to 86%.
Conclusions: The trauma surgeon’s conclusions concerning a patients bone quality can be trusted to some degree.

31. Influence of computer tomography scans on treatment of bi- and trimalleolar fractures
Mads Terndrup, Amandus Gustafsson, Kolja Weber, Kristoffer Barfod, Anders Troelsen, Ilija Ban
Ortopædkirurgisk afdeling, Hvidovre Hospital; Ortopædkirurgisk afdeling, Rigshospitalet; Ortopædkirurgisk afdeling, Rigshospitalet; Ortopædkirurgisk afdeling, Køge hospital; Ortopædkirurgisk afdeling, Hvidovre hospital; Ortopædkirurgisk afdeling, Hvidovre hospital


Background: Several studies have indicated that plain radiographs are insufficient in evaluation of complex malleolar fractures. In one recent study this was especially true for trimalleolar fractures, dislocated fractures, suprasyndesmotic fractures and in cases where plaster obscured the fracture area. However these studies have been either small or retrospective
Purpose / Aim of Study: To assess change of planned operative management (patient positioning, surgical approach and fixation) between preoperative x- ray and CT-evaluation
Materials and Methods: Adult patients with bi- or trimalleolar fractures or unimalleolar fractures with dislocation were CT-scanned. The surgeon subsequently filled out a purpose made form after 1) evaluation of x-rays, 2) evaluation of CT-scans and 3) performed surgery. The form addressed among others AO classification, location of fracture step-off, patient positioning, planned incisions and fixation of medial and lateral malleoli, posterior tibia and the syndesmosis. 69 patients were included
Findings / Results: Change in AO-classification (p= .035) and presence of fracture step-off in the posterior tibia (p= .003) was significant after x-ray and CT-scan evaluation. Changes in planned incisions (17,4%) and patient positioning (8,7%) were more frequent after X-ray and CT- scan evaluation compared to plan after CT and performed surgery, (1,4%) and (4,3%) respectively, but these findings were non- significant. Changes in planned fixation after x- ray and CT-scan evaluation (29,0%) was lower than the change seen between plan after CT- scan and actually performed surgery (37,7%)
Conclusions: The role of preoperative CT-scans in the management of ankle fractures is unclear. Our results indicate a more precise AO classification and detection of fracture step-off in the posterior tibia, but CT-scans do not seem to change surgical management

32. Function, health status and satisfaction after surgery with THA following femoral neck fracture or osteoarthritis.
Steffan Tabori Jensen, Torben Bæk Hansen, Søren Bøvling, Morten Homileus, Peter Aalund, Maiken Stilling
Department of Orthopedics, University Clinic of Hand, Hip and Knee Surgery, Hospital Unit West.; Department of Orthopedics, University Clinic of Hand, Hip and Knee Surgery, Hospital Unit West.; Department of Orthopedics, University Clinic of Hand, Hip and Knee Surgery, Hospital Unit West.; Department of Orthopedics, University Clinic of Hand, Hip and Knee Surgery, Hospital Unit West.; Department of Orthopedics, University Clinic of Hand, Hip and Knee Surgery, Hospital Unit West.; Department of Orthopedics, University Clinic of Hand, Hip and Knee Surgery, Hospital Unit West.


Background: Displaced femoral neck fracture (FNF) is a common injury in the elderly, and treatment with total hip arthroplasty (THA) has low complication and revision rate. Less is known about the functional results after ended rehabilitation.
Purpose / Aim of Study: To investigate function, health status and satisfaction in patients treated with primary THA after displaced FNF.
Materials and Methods: From 2005-2011, 414 consecutive FNF patients were operated with Saturne Dual mobility (DM) THA. At min 1-year follow-up, 124 (95 women) responded to an invitation and were evaluated with Oxford Hip Score (OHS), a general health-related quality of life measure (EQ-5D) and 2 functional tests: Timed Up and Go (TUG) and Sit To Stand 10 times (STS). The FNF patients were matched 1:2 by age, sex and surgery date with patients receiving THA due to osteoarthrosis (OA group) with 1 year OHS and EQ5D. EQ-5D for the FNF group was matched to the general population index.
Findings / Results: Patient age at time of surgery was mean 74.8 (range 30- 92) years. At a mean follow-up of 2.8 (1.0 – 7.7) years the mean EQ-5D score was 0.79 (sd 0.15) in the FNF group, which was similar to the matched general populations index (p=0.4), but lower (p=0.001) when compared to the OA group. Mean OHS was 36.4 (sd 9.5) in the FNF group and 38.4 (sd 7.2) in the OA group (p=0.05). Hip pain (Q1 from OHS) was similar between groups (p=0.10). Mean TUG was 13.5 (sd 4.9) sec and mean STS was 37.9 (sd 15.3) sec in the FNF group. Mean VAS at rest was 1.0 (sd 1.7) and during activity 2.1 (sd 2.7), and 89% were satisfied with the result of the operation in the FNF group.
Conclusions: At short term follow-up, patients with DM THA following displaced FNF had a good functional and satisfaction result. EQ-5D was similar to the age/gender matched population index, but lower compared with OA THA patients.

33. Mortality in patients treated with cemented or uncemented hemiarthroplasty - A study from the Danish Multidisciplinary Registry of Hip Fractures (DMRHF)
Bjarke Viberg, Alma Becic Pedersen, Anders Kjærsgaard, Søren Overgaard, Jens Lauritsen
Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Clinical Epidemiology, Aarhus University Hospital; Department of Clinical Epidemiology, Aarhus University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital; Department of Orthopaedic Surgery and Traumatology, Odense University Hospital


Background: Several nationwide studies have shown that cemented hemiarthroplasty (cemHA) has higher mortality compared with uncemented (uncemHA) on the first postoperative day and lower after 1 year but longer term results are not known.
Purpose / Aim of Study: To compare the postoperative mortality after cemHA with uncemHA in hip fracture patients with up to 5 years’ follow-up.
Materials and Methods: This is a population based register study with data from the DMRHF and the Danish National Registry of Patients. Data was retrieved from 01.01.2004 to 12.31.2013 with a minimum of 2 years’ follow-up on procedure codes (NFB02, NFB12), age, sex, Charlson Comorbidity Index (CCI), reoperation status and vital status. There were 70,652 hip fractures that included 45,809 osteosyntheses, 7,020 total hip arthroplasties and 17,283 HA.
Findings / Results: There were 8751 uncemHA and 8532 cemHA, and the median age (quartiles) was 84.2 (79.1-88.7) for uncemHA and 83.8 (78.5-88.5) for cemHA. There were 76 % female in both groups and the median follow-up was 3.5 years. The mortality for uncemHA compared to cemHA was within the first postoperative day 0.8 % versus 1.2 %, and reversed already after 1 week with 3.6 % versus 3.2 %. In a Cox-regression analysis adjusted for age, sex, and CCI the Hazard Ration (HR) (95 % CI) for 1-day was 1.48 (1.10; 2.00), 1-week 0.94 (0.80; 1.10), 1 month 0.83 (0.73; 0.93), 1-year 0.87 (0.81; 0.94), and 5-years 0.98 (0.93; 1.03). The 1-day HR for cemHA patients with CCI=0 is 3.43 (1.69;6.94), 0.90 (0.57;1.41) for CCI=1-2, and 1.70 (0.99;2.91) for CCI≥3.
Conclusions: Overall mortality was higher after one day, lower from one month to one year and comparable at five years when comparing cemHA with uncemHA. An unexpected possibly U-shaped co-morbidity to mortality risk at 1-day associated with cemHA warrants further study.