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Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_12 | Pages 90 - 90
1 Dec 2022
Abbas A Toor J Du JT Versteeg A Yee N Finkelstein J Abouali J Nousiainen M Kreder H Hall J Whyne C Larouche J
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Excessive resident duty hours (RDH) are a recognized issue with implications for physician well-being and patient safety. A major component of the RDH concern is on-call duty. While considerable work has been done to reduce resident call workload, there is a paucity of research in optimizing resident call scheduling. Call coverage is scheduled manually rather than demand-based, which generally leads to over-scheduling to prevent a service gap. Machine learning (ML) has been widely applied in other industries to prevent such issues of a supply-demand mismatch. However, the healthcare field has been slow to adopt these innovations. As such, the aim of this study was to use ML models to 1) predict demand on orthopaedic surgery residents at a level I trauma centre and 2) identify variables key to demand prediction.

Daily surgical handover emails over an eight year (2012-2019) period at a level I trauma centre were collected. The following data was used to calculate demand: spine call coverage, date, and number of operating rooms (ORs), traumas, admissions and consults completed. Various ML models (linear, tree-based and neural networks) were trained to predict the workload, with their results compared to the current scheduling approach. Quality of models was determined by using the area under the receiver operator curve (AUC) and accuracy of the predictions. The top ten most important variables were extracted from the most successful model.

During training, the model with the highest AUC and accuracy was the multivariate adaptive regression splines (MARS) model, with an AUC of 0.78±0.03 and accuracy of 71.7%±3.1%. During testing, the model with the highest AUC and accuracy was the neural network model, with an AUC of 0.81 and accuracy of 73.7%. All models were better than the current approach, which had an AUC of 0.50 and accuracy of 50.1%. Key variables used by the neural network model were (descending order): spine call duty, year, weekday/weekend, month, and day of the week.

This was the first study attempting to use ML to predict the service demand on orthopaedic surgery residents at a major level I trauma centre. Multiple ML models were shown to be more appropriate and accurate at predicting the demand on surgical residents as compared to the current scheduling approach. Future work should look to incorporate predictive models with optimization strategies to match scheduling with demand in order to improve resident well being and patient care.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_13 | Pages 83 - 83
1 Dec 2022
Van Meirhaeghe J Vicente M Leighton R Backstein D Nousiainen M Sanders DW Dehghan N Cullinan C Stone T Schemitsch C Nauth A
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The management of periprosthetic distal femur fractures is an issue of increasing importance for orthopaedic surgeons. Because of the expanding indications for total knee arthroplasty (TKA) and an aging population with increasingly active lifestyles there has been a corresponding increase in the prevalence of these injuries. The management of these fractures is often complex because of issues with obtaining fixation around implants and dealing with osteopenic bone or compromised bone stock. In addition, these injuries frequently occur in frail, elderly patients, and the early restoration of function and ambulation is critical in these patients. There remains substantial controversy with respect to the optimal treatment of periprosthetic distal femur fractures, with some advocating for Locked Plating (LP), others Retrograde Intramedullary Nailing (RIMN) and finally those who advocate for Distal Femoral Replacement (DFR). The literature comparing these treatments, has been infrequent, and commonly restricted to single-center studies. The purpose of this study was to retrospectively evaluate a large series of operatively treated periprosthetic distal femur fractures from multiple centers and compare treatment strategies.

Patients who were treated operatively for a periprosthetic distal femur fracture at 8 centers across North America between 2003 and 2018 were retrospectively identified. Baseline characteristics, surgical details and post-operative clinical outcomes were collected from patients meeting inclusion criteria. Inclusion criteria were patients aged 18 and older, any displaced operatively treated periprosthetic femur fracture and documented 1 year follow-up. Patients with other major lower extremity trauma or ipsilateral total hip replacement were excluded. Patients were divided into 3 groups depending on the type of fixation received: Locked Plating, Retrograde Intramedullary Nailing and Distal Femoral Replacement. Documented clinical follow-up was reviewed at 2 weeks, 3 months, 6 months and 1 year following surgery. Outcome and covariate measures were assessed using basic descriptive statistics. Categorical variables, including the rate of re-operation, were compared across the three treatment groups using Fisher Exact Test.

In total, 121 patients (male: 21% / female: 79%) from 8 centers were included in our analysis. Sixty-seven patients were treated with Locked Plating, 15 with Retrograde Intramedullary Nailing, and 39 were treated with Distal Femoral Replacement. At 1 year, 64% of LP patients showed radiographic union compared to 77% in the RIMN group (p=0.747). Between the 3 groups, we did not find any significant differences in ambulation, return to work and complication rates at 6 months and 1 year (Table 1). Reoperation rates at 1 year were 27% in the LP group (17 reoperations), 16% in the DFR group (6 reoperations) and 0% in the RIMN group. These differences were not statistically significant (p=0.058).

We evaluated a large multicenter series of operatively treated periprosthetic distal femur fractures in this study. We did not find any statistically significant differences at 1 year between treatment groups in this study. There was a trend towards a lower rate of reoperation in the Retrograde Intramedullary Nailing group that should be evaluated further with prospective studies.

For any figures or tables, please contact the authors directly.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_12 | Pages 88 - 88
1 Dec 2022
Del Papa J Champagne A Shah A Toor J Larouche J Nousiainen M Mann S
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The 2020-2021 Canadian Residency Matching Service (CaRMS) match year was altered on an unprecedented scale. Visiting electives were cancelled at a national level, and the CaRMS interview tour was moved to a virtual model. These changes posed a significant challenge to both prospective students and program directors (PDs), requiring each party to employ alternative strategies to distinguish themselves throughout the match process. For a variety of reasons, including a decline in applicant interest secondary to reduced job prospects, the field of orthopaedic surgery was identified as vulnerable to many of these changes, creating a window of opportunity to evaluate their impacts on students and recruiting residency programs.

This longitudinal survey study was disseminated to match-year medical students (3rd and 4th year) with an interest in orthopaedic surgery, as well as orthopaedic surgery program directors. Responses to the survey were collected using an electronic form designed in Qualtrics (Qualtrics, 2021, Provo, Utah, USA). Students were contacted through social media posts, as well as by snowball sampling methods through appropriate medical student leadership intermediates. The survey was disseminated to all 17 orthopedic surgery program directors in Canada.

A pre-match and post-match iteration of this survey were designed to identify whether expectations differed from reality regarding the effect of the COVID-19 pandemic on the CaRMS match 2020-2021 process. A similar package was disseminated to Canadian orthopaedic surgery program directors pre-match, with an option to opt-in for a post-match survey follow-up. This survey had a focus on program directors’ opinions of various novel communication, recruitment, and assessment strategies, in the wake of the COVID-19 pandemic.

Students’ responses to the loss of visiting electives were negative. Despite a reduction in financial stress associated with reduced need to travel (p=0.001), this was identified as a core component of the clerkship experience. In the case of virtual interviews, students’ initial trepidation pre-CaRMS turned into a positive outlook post-CaRMS (significant improvement, p=0.009) indicating an overall satisfaction with the virtual interview format, despite some concerns about a reduction in their capacity to network. Program directors and selection committee faculty also felt positively about the virtual interview format. Both students and program directors were overwhelmingly positive about virtual events put on by both school programs and student-led initiatives to complement the CaRMS tour.

CaRMS was initially developed to facilitate the matching process for both students and programs alike. We hope to continue this tradition of student-led and student-informed change by providing three evidence-based recommendations. First, visiting electives should not be discontinued in future iterations of CaRMS if at all possible. Second, virtual interviews should be considered as an alternative approach to the CaRMS interview tour moving forward. And third, ongoing virtual events should be associated with a centralized platform from which programs can easily communicate virtual sessions to their target audience.


The Bone & Joint Journal
Vol. 95-B, Issue 11 | Pages 1445 - 1449
1 Nov 2013
Sonnadara R McQueen S Mironova P Safir O Nousiainen M Ferguson P Alman B Kraemer W Reznick R

Valid and reliable techniques for assessing performance are essential to surgical education, especially with the emergence of competency-based frameworks. Despite this, there is a paucity of adequate tools for the evaluation of skills required during joint replacement surgery. In this scoping review, we examine current methods for assessing surgeons’ competency in joint replacement procedures in both simulated and clinical environments. The ability of many of the tools currently in use to make valid, reliable and comprehensive assessments of performance is unclear. Furthermore, many simulation-based assessments have been criticised for a lack of transferability to the clinical setting. It is imperative that more effective methods of assessment are developed and implemented in order to improve our ability to evaluate the performance of skills relating to total joint replacement. This will enable educators to provide formative feedback to learners throughout the training process to ensure that they have attained core competencies upon completion of their training. This should help ensure positive patient outcomes as the surgical trainees enter independent practice.

Cite this article: Bone Joint J 2013;95-B:1445–9.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_II | Pages 253 - 253
1 May 2009
Haydon CM Bukczynski J Nousiainen M Schemitsch EH Stephen D Wadell JP
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Early fracture stabilization has been shown to reduce morbidity and mortality in the patient who is multiply injured. Controversy exists in terms of managing multiple trauma patients who sustain thoracic injuries along with femoral shaft fractures. The purpose of the present study was to determine whether the presence and treatment of femoral shaft fractures increases morbidity in patients with pulmonary contusions and to determine the effect of patient and surgical factors on outcome.

Patients that suffered chest injuries between January 1987 and April 2006 were identified from the prospectively collected trauma databases at two hospitals. Patient records were reviewed to verify all data. The diagnosis of pulmonary contusion was confirmed with radiologic or post-mortem investigations. All relevant patient and surgical data was collected. Exclusion criteria included severely injured patients (head/abdomen AIS> 3), age sixty years, death twenty-four hours after injuries occurred.

A total of 1190 patients with confirmed pulmonary contusions met inclusion criteria; there were 113 femoral shaft fractures (five bilateral). Patients in both the isolated pulmonary contusion and pulmonary contusion with femoral fracture had similar injury severity scores (ISS) and demographic information. Fractures were reduced with intramedullary nailing in 88% of cases. Mean age was thirty-five years. There were significantly more incidences of fat embolism syndrome and acute lung injury (ALI) in patients with femoral factures (twenty-four hours following the injury had significantly greater risk of developing ARDS (p< 0.05).

The presence of femoral shaft fractures in patients with pulmonary contusions increases the duration of admittance to hospital and can lead to higher rates of fat embolism syndrome and ALI, however it does not appear to impact overall mortality or contribute to the development of other common respiratory complications. Early reduction of shaft fractures is encouraged to further decrease complications.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 58 - 58
1 Mar 2008
Borden A Schemitsch E Waddell J McKee M Morton J Nousiainen M McConnell A
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We evaluated the clinical, radiographic, and functional outcome of uncemented total hip arthroplasty (THA) following vascularized fibular grafting for avascular necrosis (AVN) of the femoral head. A group of twenty-two patients who had been converted from a vascularized fibular graft to THA was compared to a similar group of twenty-two patients who had received a THA with no prior graft. The graft group was found to have worse outcomes than the control group as measured by SF-36, and WOMAC scores, as well as a hip score.

These results show that vascularized fibular grafting complicates future THA.

The Purpose of this study was to evaluate the clinical, radiographic, and functional outcome of uncemented total hip arthroplasty (THA) following vascularized fibular grafting for avascular necrosis (AVN) of the femoral head. These results indicate that functional and clinical outcome following post-graft THA is worse than outcome following THA performed as a primary intervention.

Judicious use of the vascularized fibular graft procedure is critical in order to minimize the number of graft failures and avoid the negative outcomes associated with THA after failed vascularized fibular grafting.

Twenty-six hips in twenty-two patients who had a THA following a failed vascularized fibular graft were compared to a group of twenty-three hips in twenty-two age and sex-matched patients who had received a THA with no prior graft (combined mean age: 39.0 yrs). Primary outcome measures included the SF-36 (patient-based general health assessment – total score and physical sub-component) and WOMAC (patient-based arthritis specific score) scores at matched follow up times (mean: 6.2years, range: two to fourteen years). An objective hip score was also used, as were several radiographic variables. The post-graft group had lower SF-36 final scores (p< 0.006), lower SF-36: physical function scores (p< 0.001), and lower WOMAC scores (p< 0.045) than the control group. Post-graft THA was complicated by longer operative time (p< 0.025) and greater subsidence of the femoral prosthesis (p< 0.004) compared to controls. Additionally, the post-graft group had worse hip score values (p< 0.05) than controls.

Vascularized fibular grafting is a commonly used procedure to cure or delay progression of AVN in the hip. Currently this procedure is used for young (< 40 years) patients with hip AVN who are in an early, pre-collapse stage of the disease. Although the efficacy of vascularized fibular grafting has been proven, up to 29% of grafts fail at five years and need to be converted to THA (Urbaniak et al., 1995). This study shows that THA after failed vascularized fibular grafting has a worse outcome than THA as a primary intervention. Therefore judicious use of the graft procedure is critical in order to minimize the number of graft failures and avoid the negative outcomes associated with it.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 95 - 95
1 Mar 2008
Nousiainen M Schemitsch E Waddell J McKee M Roposch A
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This study investigated the effect presence, method, and timing of fixation of femoral shaft fractures have on the morbidity and mortality of patients with pulmonary contusion.

In the multiply-injured patient with femoral shaft fractures, early (< 24 hours) fracture stabilization with closed, reamed, statically-locked intramedullary nailing has been shown to decrease morbidity and mortality. Controversy exists as to whether such treatment compromises the outcome in patients that have significant co-existing pulmonary injury. This study is the first to specifically investigate the sub-group of patients that have pulmonary contusion.

A retrospective review of patients presenting to a Level One trauma center from 1990 to 2002 with pulmonary contusion identified three hundred and twenty-two cases. Patient characteristics of age, sex, GCS, ISS, AIS, presence of femoral shaft fracture, method and timing of treatment of femoral shaft fracture, and presence of other pulmonary injuries were recorded, as were the outcomes of pulmonary complications (acute lung injury (ALI), ARDS, fat embolism syndrome, pulmonary embolism, and pneumonia), days on ventilatory support, days in the intensive care unit and ward, and death.

There were no significant differences in the patient characteristics between groups with and without femoral shaft fracture. Except for an increased likelihood of the femoral shaft fracture group having ALI (RR 1.11), there were no significant differences in outcomes between the femur fracture/non-femur fracture groups. As well, there were no significant differences in outcomes between the groups that had fracture fixation before or after twenty-four hours or had the fracture fixed with or without intramedullary nailing.

The presence, method, and timing of treatment of femoral shaft fractures do not increase the morbidity or mortality of trauma patients that have pulmonary contusion.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 8 - 8
1 Jan 2004
Waddell J Lever J Schemitsch E Nousiainen M Aksenov S
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Twelve pairs of fresh-frozen, cadaveric femora were harvested. Each right femur was prepared for the cemented insertion of the femoral component of a total hip implant. Left femora served as matched intact controls. Following insertion of the implants, the distal tip of the stem was identified and an oblique osteotomy was made to represent a periprosthetic fracture. Proximally, plates were secured with cables and distally by bicortical screw fixation (c+s). The twelve pairs of femora were randomly divided into three groups: 1. Zimmer Cable-Ready System, 2. AO 4.5 mm broad, LC-DCP, with Wire Mounts and Double Luque Wires, 3. Dall-Miles Cable Grip System. Specimens were mounted and deforming forces were applied to test the biomechanical stiffness of the constructs. Following testing the plate-cable combinations, the proximal cables were removed and replaced with unicortical screws (s+s). Repeat testing was then performed as per the above protocol.

The stiffness of the constructs relative to intact bone decreased (p< 0.05) with fixation utilising cables plus screws (c+s) during four-point bending (69–77%) and offset rotational loading (61–64%). When testing unicor-tical plus bicortical screw fixation (s+s) in these modes, a similar effect was seen. There was no difference between plate systems (ANOVA, p> 0.05). Comparisons of stiffness between cable plus screw combination versus unicor-tical plus bicortical screw combination revealed that the latter method of fixation (s+s) was more rigid (p< 0.05).

Our study showed that the three plate-cable systems displayed similar biomechanical stiffness. In addition, when the cables were replaced proximally with unicortical screws, more rigid fixation was obtained in all but one plane of testing.

We conclude that the method of plate stabilisation by screws or cables is more significant than the type of plate used for periprosthetic fracture stabilisation.