Daniel L. Riddle

Volume of Ambulatory Care Visits and Patterns of Care for Patients Diagnosed with Plantar Fasciitis: A National Study of Medical Doctors

Background: Plantar fasciitis is a relatively common disorder of the foot, yet little is known about its prevalence, what types of physicians see patients with the disorder, or how, on a national scale, patients are typically managed. The purpose of this study was to generate national estimates of the volume of patient visits and characteristics of care given to patients diagnosed with plantar fasciitis by medical doctors. Methods: Data from the National Ambulatory Medical Care Survey (NAMCS) and the National Hospital Ambulatory Medical Care Survey (NHAMCS) for the years 1995–2000 were studied. These are multistage probability sample surveys of visits to office-based physicians (NAMCS) and visits to nonfederal, short-stay, and general hospitals (NHAMCS) to consult doctors of medicine and doctors of osteopathy. Sample data have been weighted to produce national estimates. Data describing the number of patient visits for plantar fasciitis and the characteristics of the care given during those visits were summarized using univariate analyses. Data were combined for the 6-year period to increase the reliability of the estimates, and figures are presented as annual averages. Results: Approximately 1 million patient visits per year were made to office-based physicians and hospital outpatient departments for the diagnosis and treatment of plantar fasciitis during 1995–2000. Approximately 62% of all visits were made to primary care practitioners, and 31% were made to orthopaedic surgeons. Patient visits for plantar fasciitis accounted for approximately 1% of all patient visits to orthopedic surgeons. Pain medication, including nonsteroidal anti-inflammatory drugs (NSAIDs), was the most frequently used intervention (47% of visits). Exercise counseling was cited at 26% of visits, and physical therapy was ordered or provided at 19% of visits. Conclusions: This research suggests that plantar fasciitis is a relatively common disorder that is seen by several physician specialties. The disorder is not managed in a consistent way. Rather, there appears to be a large amount of variation in the way that these patients are managed. These findings support the argument that additional research is needed to identify effective interventions for plantar fasciitis and to determine if physician specialty influences treatment outcome.

Impact of psychological distress on pain and function following knee arthroplasty

BACKGROUND Preoperative psychological distress has been reported to be an important risk factor for poor outcome following lower-extremity arthroplasty. We determined the independent impact of preoperative psychological distress on three, twelve, and twenty-four-month WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) pain and function scores and on change scores over those time periods. METHODS Data were obtained from an international group of 952 patients in thirteen centers participating in the Kinemax Outcomes Study. Patients completed the WOMAC and Short Form-36 (SF-36) questionnaires. The mental health (MH) scale of the SF-36 was used to quantify the impact of psychological distress on WOMAC pain and function scores. We also dichotomized patients into groups with and without psychological distress on the basis of evidence-based cut-points. Repeated-measures models were used to derive mean preoperative and three, twelve, and twenty-four-month WOMAC pain and function scores and general linear models were used to derive change scores for patients with and without psychological distress after adjustment for covariates. RESULTS Psychological distress, when examined on a continuous scale, was found to predict pain and function at all time-points. WOMAC pain scores for psychologically distressed patients were 3 to 5 points lower, depending on the time-frame, than the scores for the non-distressed patients, after adjustment for covariates. WOMAC function scores did not differ significantly between the two groups following surgery. The changes in the WOMAC pain and function scores for the psychologically distressed patients were not significantly different from those for the non-distressed patients. CONCLUSIONS Many patients with psychological distress demonstrate a substantial decrease in that distress following surgery. Patients who are distressed have slightly worse pain preoperatively and for up to two years following knee arthroplasty as compared with patients with no psychological distress. With the exception of preoperative scores, these differences are not likely to be measurable at the individual patient level. WOMAC pain and function change scores do not differ between patients with and without distress after adjustment for covariates. LEVEL OF EVIDENCE Prognostic Level I.

Assessing Recovery and Establishing Prognosis Following Total Knee Arthroplasty

Background and Purpose: Information about expected rate of change after arthroplasty is critical for making prognostic decisions related to rehabilitation. The goals of this study were: (1) to describe the pattern of change in lower-extremity functional status of patients over a 1-year period after total knee arthroplasty (TKA) and (2) to describe the effect of preoperative functional status on change over time. Subjects: Eighty-four patients (44 female, 40 male) with osteoarthritis, mean age of 66 years (SD=9), participated. Methods: Repeated measurements for the Lower Extremity Functional Scale (LEFS) and the Six-Minute Walk Test (6MWT) were taken over a 1-year period. Data were plotted to examine the pattern of change over time. Different models of recovery were explored using nonlinear mixed-effects modeling that accounted for preoperative status and gender. Results: Growth curves were generated that depict the rate and amount of change in LEFS scores and 6MWT distances up to 1 year following TKA. The curves account for preoperative status and gender differences across participants. Discussion and Conclusion: The greatest improvement occurred in the first 12 weeks after TKA. Slower improvement continued to occur from 12 weeks to 26 weeks after TKA, and little improvement occurred beyond 26 weeks after TKA. The findings can be used by physical therapists to make prognostic judgments related to the expected rate of improvement following TKA and the total amount of improvement that may be expected.

Yearly Incidence of Unicompartmental Knee Arthroplasty in the United States

Our purpose was to estimate the incidence of unicompartmental knee arthroplasty in the United States. Three major implant manufacturers provided data over an 8-year period from 1998 to 2005. In addition, a database from 44 hospitals was used to derive national estimates for implants manufactured by all other companies. The incidence of unicompartmental knee arthroplasty ranged from 6570 implants in 1998 to 44990 in 2005. Unicompartmental knee arthroplasty increased at an average rate of 32.5% during the study period compared with a 9.4% average increase in rate of total knee arthroplasty over the same period. Although unicompartmental arthroplasty is growing at triple the rate of total knee arthroplasty in the United States, the data suggest that unicompartmental implants currently account for less than 8% of all knee arthroplasty procedures.

Assessing sensitivity to change: choosing the appropriate change coefficient

The past 20-years have seen the development and evaluation of many health status measures. Unlike the high standards demanded of those who conduct and report clinical intervention trials, the methodological rigor for studies examining the sensitivity to change of health status measures are less demanding. It is likely that the absence of a criterion standard for change in health status contributes to this shortcoming. To increase confidence in the results of these types of studies investigators have often calculated multiple change coefficients for the same patient sample.The purpose of this report is to identify the conflict that arises when multiple change coefficients are applied to the same patient sample.Three families of change coefficients based on different assumptions concerning the sample composition are identified: (1) the sample is homogeneous with respect to change; (2) subgroups of patients who truly change by different amounts exist; (3) individual patients, many of whom truly change by different amounts exist. We present several analyses which illustrate a major conceptual conflict: the signal (a measures true ability to detect change) for some of these coefficients appears in the noise term (measurement error) of the others.We speculate that this dilemma occurs as a result of insufficient preparatory work such as pilot studies to establish the likely change characteristic of the patient population of interest. Uncertainty in the choice of change coefficient could be overcome by conducting pilot studies to ascertain the likely change characteristic of the population of interest. Once the populations change characteristic is identified, the choice of change coefficient should be clear.

Development and Initial Validation of the Back Pain Functional Scale

Study Design. A prospective repeated-measures design was applied. Objectives. To examine the measurement properties of the Back Pain Functional Scale (BPFS) and the Roland–Morris Questionnaire (RMQ) and to formulate hypotheses and sample size estimates for a subsequent comparison study. Summary of Background Data. Although there are numerous functional status measures for patients with low back pain, most have been conceived of and validated with a group rather than an individual patient as the unit of interest. Also, little has been done to formally compare—this includes the generation of a priori hypotheses, followed by statistical hypotheses testing—the many competing measures. Methods. Subjects were 77 patients with low back pain who were referred by physicians to 10 outpatient physical therapy clinics located in Canada and the United States. The questionnaires were administered at patients’ initial visits, within 48 hours of the initial visit, and at 1-, 2-, and 3-week follow-up visits. Reliability, cross-sectional validity, and longitudinal validity (sensitivity to change) coefficients were calculated. Results. Test–retest reliability estimates of 0.81 and 0.88 were obtained for the RMQ and BPFS, respectively. The measures demonstrated similar levels of cross-sectional validity. Correlations of 0.56 and 0.65 were noted between a prognostic rating of change and the RMQ and BPFS, respectively. The RMQ demonstrated a ceiling effect. Approximately 180 patients are needed for a subsequent head-to-head comparison study of the measures. Conclusions. The BPFS appears to have sound measurement properties, and a formal head-to-head comparison study with the RMQ is warranted.

Intertester reliability of McKenzie's classifications of the syndrome types present in patients with low back pain.

The McKenzie system for examining and treating patients with low back pain is frequently used by clinicians. The primary purpose of this multicenter study was the determine the intertester reliability of assessments of patients with low back pain when physical therapists used the McKenzie method. A second purpose was to determine if previous postgraduate training in the McKenzie system affects reliability. Some therapists had previously undertaken postgraduate training in the McKenzie system. All therapists were given written descriptions of the McKenzie method and the criteria used to classify patients, Classifications were made on 363 patients with low back pain by randomly paired physical therapists in eight clinics. The Kappa value on agreement of patient classification was 0.26, which suggests poor reliability. Therapists agreed on which syndrome was present 39% of the time. Previous postgraduate training did not reliability. The results suggest that assessments of the syndrome present in patients; with low back pain appear to be unreliable when using the McKenzie system.

Findings of extensive variation in the types of outcome measures used in hip and knee replacement clinical trials: A systematic review

OBJECTIVE To describe the extent of variation in outcome measure usage in hip and knee replacement randomized trial literature, and to summarize this variation in the context of the International Classification of Functioning, Disability, and Health (ICF) conceptual model created by the World Health Organization (WHO). METHODS We used a defined search strategy in Medline and EMBase databases to identify articles published from January 2000 to February 2007. Studies were reviewed if they were randomized trials with a >or=6-week followup and if they used noninvasive outcome measures of impaired joint function or whole-person limitations in daily activities or functional status. The WHO ICF model was used to categorize outcome measures. RESULTS Of 972 studies, 160 were included for review. Of these, 82 were conducted on patients with hip replacements, 75 on patients with knee replacements, and 3 on patients with both. The most common outcome measure in knee trials was the American Knee Society score (used in 48% of reviewed studies), and in hip trials was the Harris hip score (52.4%). At least 20 different outcome measures were used in the hip trials, and at least 14 different measures were used in knee trials. The primary outcome was identified in only 24% of trials. CONCLUSION We found extensive variation in outcome measures across trials and saw inconsistency across the components of the WHO ICF model. To improve interpretability, future work should determine whether consensus can be developed for a standardized set of outcome measures for hip and knee replacement trials.

Impact of Demographic and Impairment-Related Variables on Disability Associated with Plantar Fasciitis:

Background: Plantar fasciitis is a common foot disorder that impacts many functional activities. Research that quantifies the impact that plantar fasciitis has on function is lacking. In addition, little is known about which variables are associated with disability in patients with plantar fasciitis. The first purpose of this study was to determine if age, gender, body mass index, pain intensity, chronicity of symptoms, or ankle dorsiflexion range of motion was associated with disability in patients with plantar fasciitis. The second purpose was to describe the impact that plantar fasciitis has on functional status in the context of five functional domains: household activities of daily living, usual work and hobbies, nonweightbearing activities, walking-related activities, and running-related activities. Methods: Fifty consecutive patients diagnosed with unilateral plantar fasciitis were recruited. Demographic and impairment data were collected and all patients completed the Lower Extremity Functional Scale (LEFS), a validated self-report measure of disability. Multiple regression analysis was used to describe the association between the variables and disability. Graphs depicting five domains of function derived from the LEFS were generated to describe the extent of disability. Results: Body mass index (BMI) was the only variable that was significantly associated with disability (F = 9.87, p = .003). Measures of pain intensity, ankle dorsiflexion, age, gender, chronicity, and time spent weightbearing were not related to disability. Plantar fasciitis showed distinct patterns of disability depending on the functional domain that was assessed. Conclusions: With the exception of BMI, impairment and demographic variables do not predict the extent of functional loss in patients with plantar fasciitis. The most likely domains of function to be at least moderately affected in patients with plantar fasciitis are running-related activities and usual work or hobbies.

Pain Coping Skills Training for Patients With Elevated Pain Catastrophizing Who Are Scheduled for Knee Arthroplasty: A Quasi-Experimental Study

OBJECTIVES To (1) describe a behavioral intervention designed for patients with elevated pain catastrophizing who are scheduled for knee arthroplasty, and (2) use a quasi-experimental design to evaluate the potential efficacy of the intervention on pain severity, catastrophizing cognitions, and disability. DESIGN Quasi-experimental nonequivalent control group design with a 2-month follow-up. SETTING Two university-based orthopedic surgery departments. PARTICIPANTS Adults (N=63) scheduled for knee replacement surgery who reported elevated levels of pain catastrophizing. Patients were recruited from 2 clinics and were assessed prior to surgery and 2 months after surgery. INTERVENTIONS A group of 18 patients received a psychologist-directed pain coping skills training intervention comprising 8 sessions. The other group, a historical cohort of 45 patients, received usual care. MAIN OUTCOME MEASURES Western Ontario and McMaster Universities Arthritis Index Pain and Disability scores, as well as scores on the Pain Catastrophizing Scale. RESULTS Two months after surgery, the patients who received pain coping skills training reported significantly greater reductions in pain severity and catastrophizing, and greater improvements in function as compared to the usual care cohort. CONCLUSIONS Pain catastrophizing is known to increase risk of poor outcome after knee arthroplasty. The findings provide preliminary evidence that the treatment may be highly efficacious for reducing pain, catastrophizing, and disability, in patients reporting elevated catastrophizing prior to knee arthroplasty. A randomized controlled trial is warranted to confirm these effects.