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Dive into the research topics where Denise S. Chan is active.

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Featured researches published by Denise S. Chan.


American Journal of Sports Medicine | 2008

A Randomized Clinical Trial Comparing Open to Arthroscopic Acromioplasty With Mini-Open Rotator Cuff Repair for Full-Thickness Rotator Cuff Tears: Disease-Specific Quality of Life Outcome at an Average 2-Year Follow-Up

Nicholas Mohtadi; Robert M. Hollinshead; Treny M. Sasyniuk; Jennifer A. Fletcher; Denise S. Chan; Feng X. Li

Background Rotator cuff tears affect patients’ quality of life. The evolution toward less invasive operative techniques for rotator cuff repair requires appropriate comparisons with the standard open procedure, using validated outcomes in a randomized fashion. Hypothesis There is no difference in disease-specific quality of life outcomes at 2 years between an open surgical repair (open) versus an arthroscopic acromioplasty with mini-open (scope mini-open) repair for patients with full-thickness rotator cuff tears. Study Design Randomized controlled trial; Level of evidence, 1. Methods Patients with unremitting pain, failed nonoperative treatment, and imaging indicating full-thickness rotator cuff tears were included in the study. Massive irreparable cuff tears were excluded. Patients were assessed using the disease-specific Rotator Cuff-Quality of Life index, which produces a maximum score of 100, representing a high quality of life. Secondary shoulder-specific outcomes (American Shoulder and Elbow Society, Shoulder Rating Questionnaire, and Functional Shoulder Elevation Test) were also measured at baseline, 3 and 6 months, and 1 and 2 years. Results The mean Rotator Cuff-Quality of Life scores at an average follow-up of 28 months were not statistically different: open, 86.9 (95% confidence interval: 81.8–92.0); and scope mini-open, 87.2 (95% confidence interval: 80.6–93.8). At 3 months, the patients who underwent scope mini-open showed statistically significantly better outcomes (55.6 vs 71.3; P = .005). The baseline to 3-month difference in Rotator Cuff-Quality of Life scores between the scope mini-open and open groups was also statistically significant. Conclusion Patient outcomes improved from baseline to all postoperative measurement intervals. There was no difference in outcome at 1 and 2 years after surgery between the scope mini-open and open procedures. The quality of life of patients undergoing the arthroscopic acromioplasty with mini-open rotator cuff repair improved statistically significantly and clinically at 3 months compared with the open group.


Journal of Bone and Joint Surgery, American Volume | 2014

A Randomized Clinical Trial Comparing Open and Arthroscopic Stabilization for Recurrent Traumatic Anterior Shoulder Instability Two-Year Follow-up with Disease-Specific Quality-of-Life Outcomes

Nicholas Mohtadi; Denise S. Chan; Robert M. Hollinshead; Richard S. Boorman; Laurie A. Hiemstra; Ian K.Y. Lo; Heather N. Hannaford; Jocelyn Fredine; Treny M. Sasyniuk; Elizabeth Oddone Paolucci

BACKGROUND The literature comparing open and arthroscopic repair for glenohumeral instability is conflicting. We performed a prospective, expertise-based, randomized clinical trial to compare open shoulder stabilization with arthroscopic shoulder stabilization by measuring quality-of-life outcomes and recurrence rates at two years among patients treated for traumatic anterior shoulder instability. METHODS Computer-generated, variable-block-size, concealed randomization allocated 196 patients to either the open-repair group (n = 98) or the arthroscopic-repair group (n = 98). An expertise-based randomization design was employed to avoid a differential bias in terms of physician experience. Outcomes were measured at baseline, at three and six months postoperatively, and at one and two years postoperatively with use of the Western Ontario Shoulder Instability Index (WOSI) and the American Shoulder and Elbow Surgeons (ASES) functional outcome scale. Recurrent instability was also analyzed. RESULTS There were no significant differences in outcome scores at baseline. At two years, seventy-nine patients in the open group and eighty-three patients in the arthroscopic group were available for follow-up. There was no significant difference in mean WOSI scores between the groups; the mean WOSI score (and standard deviation) for the open group was 85.2 ± 20.4 (95% confidence interval [CI] = 80.5 to 89.8), and for the arthroscopic group, 81.9 ± 19.8 (95% CI = 77.4 to 86.4); p = 0.31. There was also no significant difference in mean ASES scores: 91.4 ± 12.7 (95% CI = 88.5 to 94.4) for the open group and 88.2 ± 15.9 (95% CI = 84.6 to 91.8) for the arthroscopic group; p = 0.17. Recurrence rates at two years were significantly different: 11% in the open group and 23% in the arthroscopic group (p = 0.05). Recurrent instability was more likely in patients with a preoperative Hill-Sachs lesion and in male patients who were twenty-five years old and younger. There was no significant difference in shoulder motion between the groups at two years. CONCLUSIONS There was no difference between open and arthroscopic repair in terms of patient quality of life. Open repair resulted in a significantly lower risk of recurrence. Secondary outcome data from this trial suggest that open surgical repair may be recommended to reduce the risk of recurrent instability in younger male patients with a Hill-Sachs lesion.


Trials | 2006

A multi-centre randomized controlled trial comparing electrothermal arthroscopic capsulorrhaphy versus open inferior capsular shift for patients with shoulder instability: Protocol implementation and interim performance: Lessons learned from conducting a multi-centre RCT [ISRCTN68224911; NCT00251160]

Nick Mohtadi; Robert M. Hollinshead; Pj Ceponis; Denise S. Chan; Gordon H. Fick

BackgroundThe shoulder is the most frequently dislocated joint in the body. Multiple causes and pathologies account for the various types of shoulder instability. Multi-directional instability (MDI) and multi-directional laxity with antero-inferior instability (MDL-AII) are similar in pathology, less common and more difficult to treat. These instabilities are caused by ligamentous capsular redundancy. When non-operative management fails for these patients, quality of life is significantly impaired and surgical treatment is required to tighten the ligaments and joint capsule. The current reference (gold) standard treatment for MDI/MDL-AII is an open inferior capsular shift (ICS) surgical procedure. An alternative treatment involves arthroscopic thermal shrinkage of redundant capsular tissue to tighten the joint. However, there is a lack of scientific evidence to support the use of this technique called, electrothermal arthroscopic capsulorrhaphy (ETAC). This trial will compare the effectiveness of ETAC to open ICS in patients with MDI and MDL-AII, using patient-based quality of life outcome assessments.MethodsThis study is a multi-centre randomized clinical trial with a calculated sample size of 58 patients (p = 0.05, 80% power). Eligible patients are clinically diagnosed with MDI or MDL-AII and have failed standardized non-operative management. A diagnostic shoulder arthroscopy is performed to confirm eligibility, followed by intra-operative randomization to the ETAC or ICS surgical procedure. The primary outcome is the disease-specific quality of life questionnaire (Western Ontario Shoulder Instability Index), measured at baseline, 3, 6, 12 and 24 months. Secondary outcomes include shoulder-specific measures (American Shoulder and Elbow Surgeons Score and Constant Score). Other outcomes include recurrent instability, complications and operative time.The outcome measurements will be compared on an intention-to-treat basis, using two-sample independent t-tests to assess statistical significance. A Generalized Estimated Equations (GEE) analysis will determine whether there is an effect over time.DiscussionThis ongoing trial has encountered unexpected operational and practical issues, including slow patient enrollment due to high intra-operative exclusion rates. However, the authors have a greater understanding of multi-directional laxity in the shoulder and anticipate the results of this trial will provide the medical community with the best scientific clinical evidence on the efficacy of ETAC compared to open ICS.


Rheumatology | 2012

An Innovative Canadian Solution for Improved Access to Care for Knee Injuries Using “Non-Physician Experts”: The Calgary Acute Knee Injury Clinic

Nicholas Mohtadi; Denise S. Chan; Breda H. F. Lau; Mark R. Lafave

There is a significant burden of musculoskeletal (MSK) disorders on the Canadian healthcare system which emphasizes the need for improved patient flow and integrated services throughout the MSK clinical care pathway. Improving accessibility, effectiveness, acceptability and efficiency of safe and appropriate care of MSK health using innovative models of healthcare delivery has become an important issue for Canada. This paper is a prospective study that describes and evaluates an evidence-based model for management acute knee injuries in Calgary, Alberta, Canada: the Calgary Acute Injury Knee Clinic model (C-AKIC). C-AKIC model development consisted of three stages: 1) development, implementation and evaluation of a new non-physician expert (NPE) curriculum; 2) identification of the logistics for opening the C-AKIC within an urban setting; and 3) evaluation of the accessibility, effectiveness, acceptability and efficiency of the C-AKIC model relative to the current healthcare system. NPE curriculum improved both theoretical knowledge (12% average increase) and clinical competence (33.5% average increase). NPEs evaluated and managed acute knee injuries in an interdisciplinary team (2 NPEs and a primary care physician) at the C-AKIC. Patients were significantly more satisfied with the new clinical care pathway (M = 91.20 out of 100) compared to patients who went through the existing/traditional pathway (M = 75.58 out of 100). Patients also saw fewer healthcare providers in C-AKIC clinical care pathway (M = 2.14) in a shorter period of time (M = 2.09 months) compared to the existing system: M = 2.76 months and; M = 7.24 months, respectively. This project demonstrated a unique and efficient approach to evaluation and management acute knee injuries in an urban setting by providing a potentially viable solution to the need for human resources in the healthcare workforce.


American Journal of Sports Medicine | 2017

Return to Sport-Specific Performance After Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review.

Nicholas Mohtadi; Denise S. Chan

Background: Physicians counseling athletes on the prognosis of sport-specific performance outcomes after anterior cruciate ligament reconstruction (ACLR) depend on the published literature. However, critical appraisal of the validity and biases in these studies is required to understand how ACLR affects an athlete’s ability to return to sport, the athlete’s sport-specific performance, and his or her ability to achieve preinjury levels of performance. Purpose: This review identifies the published prognostic studies evaluating sport-specific performance outcomes after ACLR. A risk of bias assessment and summaries of return to sport and career longevity results are provided for each included study. Study Design: Systematic review. Methods: Electronic databases (Ovid MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and PUBMED) were searched via a defined search strategy with no limits, to identify relevant studies for inclusion in the review. A priori defined eligibility criteria included studies measuring sport-specific performance within an athlete’s sport, before and after primary ACLR. Reference lists of eligible studies were hand-searched for additional relevant studies. Data extraction was performed by use of a standardized spreadsheet. Each included study was assessed by use of 6 bias domains of the Quality in Prognosis Studies tool to critically appraise study participation, study attrition, prognostic factors, outcome measurement, confounders, and statistical analysis and reporting. Two authors independently performed each stage of the review and reached consensus through discussion. Results: Fifteen pertinent prognostic studies evaluated sport-specific performance outcomes and/or return to play after ACLR for athletes participating in competitive soccer, football, ice hockey, basketball, Alpine ski, X-Games ski and snowboarding, and baseball. Twelve of these studies were considered to have a high level of bias. Conclusion: This review demonstrated that most high-performance or professional athletes returned to their preinjury level of sport after ACLR. The bulk of evidence suggests there was a measurable decrease in performance statistics, although this is highly sport-specific. A paucity of literature is available that addresses sport-specific performance in athletes after ACLR. This review has determined that the available literature is highly biased and must be read with caution. Clinical Relevance: By better understanding the validity and biases in the published literature, physicians can provide more informed prognoses about return to sport-specific performance after ACLR while considering risk factors relevant to their patients. Registration: CRD42016046709 (International Prospective Register of Systematic Reviews, https://www.crd.york.ac.uk/prospero/)


Journal of hip preservation surgery | 2016

The incidence of proximal deep vein thrombosis after elective hip arthroscopy: a prospective cohort study in low risk patients

Nicholas Mohtadi; Kelly Johnston; Cinzia Gaudelli; Denise S. Chan; Rhamona Barber; Richard Walker; Chirag Patel; Elizabeth Mackay; Elizabeth Oddone Paolucci

Prospectively assess the incidence of deep venous thrombosis (DVT) using Doppler Ultrasound, in patients receiving elective hip arthroscopy without pharmacologic/mechanical prophylaxis. One hundred and fifteen consecutive patients (mean 35.4 years, SD = 10.3) underwent elective hip arthroscopy. Patients with previous major risk factors for DVT were excluded. Signs/symptoms of DVT/pulmonary embolism were assessed at 2-week post-operatively. A bilateral whole leg Duplex color (Doppler) Ultrasonography was scheduled between 10- and 22-day post-op. The primary outcome was frequency of DVT. Secondary outcomes assessed surgical risk factors. One hundred and ten patients (mean = 34.3 years, SD = 10.1) did not get a DVT. Five patients (mean = 43.8 years, SD = 12.1) were diagnosed with a DVT, 2- to 22-day post-operatively. All DVT patients received arthroscopy in the supine position (n = 76), versus no patients in the lateral position (n = 39). Average traction time was 38 (SD = 4) and 61 (SD = 4) minutes for patients with and without a DVT, respectively. All other a priori defined risk factors were similar. Four out of five patients presented with symptoms of a DVT, confirmed by ultrasound. One patient was without symptoms/clinical findings. Four patients had a DVT restricted to the calf veins; one patient had involvement of the popliteal vein. No patients had proximal extension into the thigh or pelvis. No pulmonary emboli were suspected or occurred. The incidence of deep venous thromboembolism is 4.3%. The majority of patients had symptomatic and distal venous thromboembolic events. This study provides supportive evidence that routine prophylaxis and/or screening may not be necessary in low risk patients undergoing elective hip arthroscopy.


Orthopaedic Journal of Sports Medicine | 2017

A Randomized Trial Comparing Patellar, Hamstring and Double-bundle ACL Reconstruction at 5-yrs

Nicholas Mohtadi; Denise S. Chan

Objectives: This prospective, double-blind RCT compares ACL reconstruction using patellar tendon, quadruple hamstring and double-bundle hamstring grafts, by measuring patient-reported disease-specific quality of life outcome in patients with isolated ACL deficiency of the knee at a 5-years post-op. Methods: Patients (n=330; 183 males, 147 females) aged 14-50 years were randomly allocated and equally distributed to one of three anatomic ACL autograft reconstruction techniques: 1) Patellar Tendon (PT; mean age 28.7 years), 2) Quadruple-stranded Hamstring Tendon (HT; mean age 28.5 years), or 3) Double-Bundle using hamstring tendons (DB; mean age 28.3 years). Computer-generated allocation with varied block randomization was performed intra-operatively. Outcomes were measured at baseline, 3 and 6 months, 1, 2 and 5 years. Two-year results were previously reported. Primary outcome: Anterior Cruciate Ligament Quality-of-Life (ACL-QOL). Secondary outcomes: International Knee Documentation Committee (IKDC) subjective score and objective grades, pivot shift, range of motion, kneeling pain, Tegner activity level, and the Cincinnati Occupational Rating Scale. The proportion of re-ruptures, partial re-ruptures and the combined total traumatic re-injuries were compared. Radiographic evaluation was performed at baseline, 2 and 5 years; this analysis is ongoing. A 5% significance level was used for all outcomes. Results: 315 randomized patients (95%) d 5-yr follow-up. There were 4 withdrawals and 11 patients lost-to-follow-up. Baseline characteristics between the groups were not different. ACL-QOL scores increased significantly from baseline over time for all groups (p=0.000). There was no difference in mean ACL-QOL score at 5-years (p=0.548): PT=82.5 (SD 17.9, 95% CI 79.0-86.0); HT=83.9 (SD 18.2, 95% CI 80.3-87.4); DB=81.1 (SD 19.3, 95% CI 77.4-84.8). At 5-years, there were no differences in the proportion of patients with a Pivot Shift grade 2 or greater (p=0.106): PT=11/98 (11%); HT=16/99 (16%); DB=23/103 (22%). Mean IKDC subjective scores were not different between groups at 5-yrs (p=0.770): PT=83.9 (SD 12.9, 95% CI = 81.4-86.5); HT=85.2 (SD 13.0, 95% CI = 82.7-87.7); DB=84.3 (SD 13.4, 95% CI = 81.7-86.9). Based on IKDC objective grades, the proportions of Normal/Nearly Normal knees at 5-years were not different between groups: PT=85/98 (87%); HT=82/99 (81%); DB=75/103 (76%), p=0.093. 5-yr Tegner activity levels and Cincinnati Occupational Scores were also not different between the groups (p=0.872 and p=0.813, respectively). Kneeling pain remained more common in the PT group (PT=10/98; HT 4/98; DB 2/101; p=0.029). More traumatic graft ruptures occurred in the HT and DB groups (PT=4/103; HT=11/105; DB=11/107; p=0.145). Revision ACL reconstructions were performed on 22 of these patients. There were an additional 11 partial graft re-ruptures (PT=0; HT=5; DB=6), with less total traumatic re-injuries in the patellar tendon group (PT=4; HT=16 and DB=17, p=0.010). Four patients had additional surgery to the index knee, not including the revision surgery between the 2 and 5-yr follow-up. Conclusion: At 5 years, there was no difference in disease-specific quality-of-life outcome or IKDC grades between the PT, HT and DB techniques for ACL reconstruction. There were significantly more traumatic graft re-injuries in the HT and DB groups compared to the PT group.


Cochrane Database of Systematic Reviews | 2011

Patellar tendon versus hamstring tendon autograft for anterior cruciate ligament rupture in adults

Nicholas Mohtadi; Denise S. Chan; Katie N. Dainty; Daniel B. Whelan


Journal of Shoulder and Elbow Surgery | 2014

Electrothermal arthroscopic capsulorrhaphy: old technology, new evidence. A multicenter randomized clinical trial

Nicholas Mohtadi; Alexandra Kirkley; Robert M. Hollinshead; Robert G. McCormack; Peter B. MacDonald; Denise S. Chan; Treny M. Sasyniuk; Gordon H. Fick; Elizabeth Oddone Paolucci


Sport-Orthopädie - Sport-Traumatologie | 2013

Anterior Cruciate Ligament preservation during reconstructive surgery: Does the extra surgical effort improve patient outcomes at one year?

Alexandra Naylor; Nicholas Mohtadi; Denise S. Chan; Rhamona S. Humphrey; Maoliosa Donald

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Alexandra Kirkley

University of Western Ontario

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