Kevin Willits
University of Western Ontario
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Featured researches published by Kevin Willits.
The New England Journal of Medicine | 2008
Alexandra Kirkley; Trevor B. Birmingham; Robert Litchfield; J. Robert Giffin; Kevin Willits; Cindy J. Wong; Brian G. Feagan; Allan Donner; Sharon Griffin; Janet E. Pope; Peter J. Fowler
BACKGROUND The efficacy of arthroscopic surgery for the treatment of osteoarthritis of the knee is unknown. METHODS We conducted a single-center, randomized, controlled trial of arthroscopic surgery in patients with moderate-to-severe osteoarthritis of the knee. Patients were randomly assigned to surgical lavage and arthroscopic débridement together with optimized physical and medical therapy or to treatment with physical and medical therapy alone. The primary outcome was the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (range, 0 to 2400; higher scores indicate more severe symptoms) at 2 years of follow-up. Secondary outcomes included the Short Form-36 (SF-36) Physical Component Summary score (range, 0 to 100; higher scores indicate better quality of life). RESULTS Of the 92 patients assigned to surgery, 6 did not undergo surgery. Of the 86 patients assigned to control treatment, all received only physical and medical therapy. After 2 years, the mean (+/-SD) WOMAC score for the surgery group was 874+/-624, as compared with 897+/-583 for the control group (absolute difference [surgery-group score minus control-group score], -23+/-605; 95% confidence interval [CI], -208 to 161; P=0.22 after adjustment for baseline score and grade of severity). The SF-36 Physical Component Summary scores were 37.0+/-11.4 and 37.2+/-10.6, respectively (absolute difference, -0.2+/-11.1; 95% CI, -3.6 to 3.2; P=0.93). Analyses of WOMAC scores at interim visits and other secondary outcomes also failed to show superiority of surgery. CONCLUSIONS Arthroscopic surgery for osteoarthritis of the knee provides no additional benefit to optimized physical and medical therapy. (ClinicalTrials.gov number, NCT00158431.)
Journal of Bone and Joint Surgery, American Volume | 2010
Kevin Willits; Annunziato Amendola; Dianne Bryant; Nicholas Mohtadi; J. Robert Giffin; Peter J. Fowler; Crystal O. Kean; Alexandra Kirkley
BACKGROUND To date, studies directly comparing the rerupture rate in patients with an Achilles tendon rupture who are treated with surgical repair with the rate in patients treated nonoperatively have been inconclusive but the pooled relative risk of rerupture favored surgical repair. In all but one study, the limb was immobilized for six to eight weeks. Published studies of animals and humans have shown a benefit of early functional stimulus to healing tendons. The purpose of the present study was to compare the outcomes of patients with an acute Achilles tendon rupture treated with operative repair and accelerated functional rehabilitation with the outcomes of similar patients treated with accelerated functional rehabilitation alone. METHODS Patients were randomized to operative or nonoperative treatment for acute Achilles tendon rupture. All patients underwent an accelerated rehabilitation protocol that featured early weight-bearing and early range of motion. The primary outcome was the rerupture rate as demonstrated by a positive Thompson squeeze test, the presence of a palpable gap, and loss of plantar flexion strength. Secondary outcomes included isokinetic strength, the Leppilahti score, range of motion, and calf circumference measured at three, six, twelve, and twenty-four months after injury. RESULTS A total of 144 patients (seventy-two treated operatively and seventy-two treated nonoperatively) were randomized. There were 118 males and twenty-six females, and the mean age (and standard deviation) was 40.4 ± 8.8 years. Rerupture occurred in two patients in the operative group and in three patients in the nonoperative group. There was no clinically important difference between groups with regard to strength, range of motion, calf circumference, or Leppilahti score. There were thirteen complications in the operative group and six in the nonoperative group, with the main difference being the greater number of soft-tissue-related complications in the operative group. CONCLUSIONS This study supports accelerated functional rehabilitation and nonoperative treatment for acute Achilles tendon ruptures. All measured outcomes of nonoperative treatment were acceptable and were clinically similar to those for operative treatment. In addition, this study suggests that the application of an accelerated-rehabilitation nonoperative protocol avoids serious complications related to surgical management.
American Journal of Sports Medicine | 1995
Anthony Miniaci; Paul A. Dowdy; Kevin Willits; A. Dale Vellet
Thirty shoulders in 20 volunteers (average age, 29 years; range, 17 to 49) with no shoulder symptoms or known abnormalities were scanned using magnetic resonance imaging. All scans were interpreted by one radiologist who was blinded to clinical data. Appearance of rotator cuff tendons on the images was graded. Grade 0 was normal, homogeneous low signal intensity structure. Grade 1 lesion was focal, linear, or diffuse intermediate signal through the tendon. Grade 2 lesion was high signal intensity within the tendon and less than full thickness. Grade 3 was high signal intensity through the full thickness of the tendon. No supraspinatus or infraspinatus tendons were grade 0 (normal); all su praspinatus and infraspinatus tendons had grade 1 changes through the tendons; and 7 of 30 (23%) of the tendons had grade 2 changes. None of the 30 shoulders had grade 3 changes in the rotator cuff tendons. There is a wide array of abnormal magnetic resonance imag ing signals in shoulders of young asymptomatic indi viduals, but they do not have full-thickness rotator cuff tears (grade 3 lesion). Nonenhanced magnetic reso nance imaging may be of limited value in defining rotator cuff injury in a patient with shoulder pain unless a full- thickness rotator cuff tear is suspected clinically.
Arthritis Care and Research | 2009
Trevor B. Birmingham; J. Robert Giffin; Bert M. Chesworth; Dianne Bryant; Robert Litchfield; Kevin Willits; Thomas R. Jenkyn; Peter J. Fowler
OBJECTIVE To evaluate the effect of medial opening wedge high tibial osteotomy on gait, radiographic, and patient-reported outcomes over a 2-year postoperative period in patients with varus alignment and medial compartment knee osteoarthritis, and to identify significant predictors of outcome. METHODS We used an observational cohort study design and prospectively administered 3-dimensional quantitative gait analysis, hip to ankle weight-bearing radiographs, and patient-reported outcomes preoperatively and 6, 12, 18, and 24 months postoperatively. Observed changes with 95% confidence intervals (95% CIs) were calculated. Multivariate linear regression and cluster analysis were used to evaluate associations between patient characteristics and 2-year outcomes in dynamic knee joint load (external knee adduction moment during gait) and Knee Injury and Osteoarthritis Outcome Scores (KOOS). RESULTS A total of 126 patients (mean age 47.48 years) were included in the study. Mean changes suggested clinically important improvements in malalignment (change in mechanical axis angle 8.04 degrees [95% CI 7.16 degrees , 8.93 degrees ]), medial compartment load during gait (change in knee adduction moment -1.38 [95% CI -1.53, -1.22] percentage body weight x height), and all KOOS domain scores (change in pain 23.19 [95% CI 19.49, 26.89] KOOS points). A small (13%) increase in knee adduction moment was observed from 6 to 24 months postoperatively. Few preoperative clinical and/or gait characteristics assessed at baseline were significantly associated with 2-year outcomes. CONCLUSION A medial opening wedge high tibial osteotomy with correction to approximately neutral alignment produces substantial and clinically important changes in dynamic knee joint load and patient-reported measures of pain, function, and quality of life 2 years postoperatively. Changes in knee adduction moment observed in the first 2 years postoperatively should be explored as potential predictors of longer-term success and subgroups of patients with poor outcomes.
Arthroscopy | 2008
Kevin Willits; Heleen Sonneveld; Annunziato Amendola; J. Robert Giffin; Sharon Griffin; Peter J. Fowler
PURPOSE To provide short-term clinical results of posterior ankle arthroscopy in the treatment of posterior ankle impingement. METHODS This was a retrospective evaluation of the clinical outcomes of posterior ankle arthroscopy in a series of patients with posterior ankle pain. RESULTS Of 23 patients who underwent 24 posterior ankle arthroscopies between July 1998 and February 2004, 15 patients (mean age, 25 years) with 16 posterior ankle arthroscopies were evaluated at a mean follow-up time of 32 months (range, 6 to 74). Procedures carried out were: excision of os trigonum (11); decompression of prominent posterior talar process (5); tenolysis of flexor hallucis longus (5); removal of loose body (1); osteochondritis dissecans lesion debridement (1); and arthrotomy (1). The average time to return to work was 1 month (range, 0 to 3) and to sports, 5.8 months (range, 1 to 24). Fourteen patients returned to their preinjury level of athletics. Mean Health Survey Short Form (SF-12) scores were 51.80 for the mental component (range, 30.77 to 60.53) and 55.80 for the physical component (range, 44.26 to 63.33). Mean score on the American Orthopaedic Foot and Ankle Society Ankle and Hindfoot Scale was 91 (range, 77 to 100) and on the Lower Extremity Functional Scale was 75 (range, 65 to 80). Documented complications included temporary numbness in the region of the scar in 5 patients and temporary ankle stiffness in 1 patient. There were no permanent neurovascular injuries. All subjects reported significant improvement and indicated that they would undergo the surgery again if needed. CONCLUSIONS Functional and clinical evaluations following posterior ankle arthroscopy revealed that all patients were very satisfied. They reported good to excellent health-related quality of life scores, satisfactory functional outcomes, and a high rate of return to sporting activities. Most importantly, no significant complications were encountered. This review suggests that posterior ankle arthroscopy is a safe and effective surgical procedure in the treatment of posterior ankle impingement. LEVEL OF EVIDENCE Level IV, therapeutic case series.
American Journal of Sports Medicine | 2014
Robin Martin; Trevor B. Birmingham; Kevin Willits; Robert Litchfield; Marie-Eve LeBel; J. Robert Giffin
Background: Previously reported complications in medial opening wedge (MOW) high tibial osteotomy (HTO) vary considerably in both rate and severity. Purpose: (1) To determine the rates of adverse events in MOW HTO classified into different grades of severity based on the treatments required and (2) to compare patient-reported outcomes between the different adverse event classifications. Study Design: Case series; Level of evidence, 4. Methods: All patients receiving MOW HTO at a single medical center from 2005 to 2009 were included. Internal fixation was used in all cases, with either a nonlocking (Puddu) or locking (Tomofix) plate. Patients were evaluated at 2, 6, and 12 weeks; 6 and 12 months; and annually thereafter. Types of potential surgical and postoperative adverse events, categorized into 3 classes of severity based on the subsequent treatments, were defined a priori. Medical records and radiographs were then reviewed by an independent observer. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores were compared in subgroups of patients based on the categories of adverse events observed. Results: A total of 323 consecutive procedures (242 males) were evaluated (age, mean ± standard deviation, 46 ± 9 years; body mass index, mean ± standard deviation, 30 ± 5 kg/m2). Adverse events requiring no additional treatment (class 1) were undisplaced lateral cortical breaches (20%), displaced (>2 mm) lateral hinge fracture (6%), delayed wound healing (6%), undisplaced lateral tibial plateau fracture (3%), hematoma (3%), and increased tibial slope ≥10° (1%). Adverse events requiring additional or extended nonoperative management (class 2) were delayed union (12%), cellulitis (10%), limited hardware failure (1 broken screw; 4%), postoperative stiffness (1%), deep vein thrombosis (1%), and complex regional pain syndrome (CRPS) type 1 (1%). Adverse events requiring additional or revision surgery and/or long-term medical care (class 3) were aseptic nonunion (3%), deep infection (2%), CRPS type 2 (1%), and severe hardware failure with loss of correction (1%). Additional surgery rate was 3%. Class 1 and 2 adverse events did not affect patient-reported outcomes at 6, 12, or 24 months postoperatively. Patients with class 3 adverse events had significantly lower total WOMAC scores at 6 months but not at 12 or 24 months postoperatively. Conclusion: The most common adverse event in MOW HTO requiring extended nonoperative treatment (class 2) is delayed union (12%). The rate of severe adverse events requiring additional surgery and/or long-term medical care (class 3) is low (7%).
Arthroscopy | 2014
Nicole Kaniki; Kevin Willits; Nicholas Mohtadi; Vincent Fung; Dianne Bryant
PURPOSE The aim of this study was to evaluate the effectiveness of platelet-rich plasma (PRP) in the nonoperative treatment of acute Achilles tendon rupture. METHODS This was a comparative study that included a prospective cohort and a historical control group. The control group was formed from a randomized trial in which one arm of the trial underwent nonoperative treatment, including accelerated functional rehabilitation after acute Achilles tendon rupture identical to that performed in the prospective treatment group. Patients in the prospective group were recruited consecutively and were administered 2 injections of PRP during the first 2 weeks after the injury. The primary outcome was isokinetic plantar flexion strength at 1 and 2 years after injury. Secondary outcomes included range of motion (ROM), calf circumference, and Leppilahti score. The ankle-hindfoot scale (American Orthopedic Functional Ankle Scale [AOFAS]) was administered to patients who received the PRP injection in the prospective group but was not measured for the historical group. RESULTS A total of 73 patients participated in the prospective PRP study group and were compared with a retrospective control group of 72 patients from a previous randomized controlled trial (RCT). The mean difference between groups in isokinetic plantar flexion strength (injured/uninjured) at 1 year after injury was -4.3% (95% confidence interval [CI], -15.9 to 7.3; P = .5) and 2.4% (95% CI, -8.6 to 13.5; P = .7) at 30°/s and 60°/s, respectively. Results at 2 years after injury were -3.1% (95% CI, -13.5 to 7.2; P = .6) and 4.8% (95% CI, -3.5 to 13.1; P = .3) at 30°/s and 60°/s, respectively. All secondary outcomes were also not statistically different. CONCLUSIONS The results of this study suggest that there is no measurable clinical benefit to the addition of PRP to the treatment regimen for nonoperatively treated acute Achilles tendon rupture. LEVEL OF EVIDENCE Level III, retrospective comparative study.
Foot & Ankle International | 1994
Annunziato Amendola; D. Vellet; Kevin Willits
CT-guided core drill excision of talar neck osteoid osteomas, in addition to other locations, appears to be a promising alternative to standard surgical treatment. As in this report, the technique is minimally invasive, which allows for complete, accurate excision and early return to activity.
Journal of Bone and Joint Surgery, American Volume | 2009
Dianne Bryant; Kevin Willits; Beate Hanson
A well-designed and executed prospective cohort study can provide high-quality evidence in the evaluation of the effectiveness of surgical interventions. In designing a cohort study to evaluate orthopaedic interventions, it is important to recognize the limitations of the design as well as the methodological features that can be incorporated to strengthen the validity of the conclusions. In this article, we discuss the importance of the appropriate selection of participants for a control group, the management of confounders, the selection of outcomes with established measurement properties (reliability, validity, and sensitivity to change), the blinded assessment of outcomes, and the impact of nonparticipants and patients lost to follow-up.
American Journal of Sports Medicine | 2014
Lyndsay Somerville; Kevin Willits; Andrew M. Johnson; Robert Litchfield; Marie-Eve LeBel; Jaydeep Moro; Dianne Bryant
Background: Shoulder pain and disability pose a diagnostic challenge for clinicians owing to the numerous causes that exist. Unfortunately, the evidence in support of most clinical tests is weak or absent. Purpose: To determine the diagnostic validity of physical examination maneuvers for rotator cuff lesions. Study Design: Cohort study (diagnosis); Level of evidence, 1. Methods: Consecutive shoulder patients recruited for this study were referred to 2 tertiary orthopaedic clinics. A surgeon took a thorough history and indicated his or her certainty about each possible diagnosis. A clinician performed the physical examination for diagnoses where uncertainty remained. Arthroscopy was considered the reference standard for patients who underwent surgery, and MRI with arthrogram was considered the reference for patients who did not. The sensitivity, specificity, and likelihood ratios were calculated to investigate whether combinations of the top tests provided stronger predictions of the presence or absence of disease. Results: There were 139 participants. None of the tests were highly sensitive for diagnosing rotator cuff tears or tendinosis. Tests for subscapularis tears were all highly specific. No optimal combination of tests improved the ability to correctly diagnose rotator cuff tears. Closer analysis revealed the internal rotation and lateral rotation lag sign did not improve the ability to diagnose subscapularis or supraspinatus tears, respectively, although the lateral rotation lag sign demonstrated a discriminatory ability for tear size. Conclusion: No test in isolation is sufficient to diagnose a patient with rotator cuff damage. A combination of tests improves the ability to diagnose damage to the rotator cuff. It is recommended that the internal rotation and lateral rotation lag signs be removed from the gamut of physical examination tests for supraspinatus and subscapularis tears.