Robert Wagenmakers

Reliability and validity of the short questionnaire to assess health-enhancing physical activity (SQUASH) in patients after total hip arthroplasty

BackgroundDespite recognized benefits of regular physical activity on musculoskeletal fitness as well as general health, little is known about the physical activity behavior of patients after Total Hip Arthroplasty (THA). So far, no physical activity questionnaire has been validated in this category of patients. As the Short Questionnaire to Assess Health-enhancing physical activity (SQUASH) has been shown to be a fairly reliable and valid tool to gauge the physical activity behavior of the general Dutch adult population, we measured the reliability and relative validity of this tool in patients after THA.Methods44 patients (17 men and 27 women, mean age 71 ± 8 years) completed the SQUASH twice with an in-between period of 2 to 6 weeks (mean 3.7). Reliability was determined by calculating the Spearman correlation coefficient between the activity scores of the separate questions as well as the total activity scores from both administrations. Additionally, a Bland & Altman analysis was performed for the total activity scores. Relative validity was determined using the Actigraph™ accelerometer, worn by 39 patients (15 men and 24 women, mean age 70 ± 8 years) for a 2-week period following the second questionnaire, as a criterion measure.ResultsSpearmans correlation coefficient for overall reliability was 0.57. It varied between 0.45 and 0.90 for the separate questions. No systematic biases between readings were found. The Spearman correlation between Actigraph™ readings and total activity score was 0.67. It was 0.56 for total minutes of activity, 0.20 for time spent in light intensity activity, 0.40 for moderate activity and 0.35 for vigorous activity. Systematic bias was found between the SQUASH and the Actigraph™.ConclusionThe SQUASH can be considered to be a fairly reliable tool to assess the physical activity behavior of patients after THA. Validity was found to be comparable with those of other questionnaires, and as it is short and easy to fill in, it may prove to be a useful tool to assess physical activity in this particular subset of the population. However, the considerable systematic bias found in this study illustrates the need for further analysis of the validity of the SQUASH.

Minimally invasive and computer-navigated total hip arthroplasty: a qualitative and systematic review of the literature

BackgroundBoth minimally invasive surgery (MIS) and computer-assisted surgery (CAS) for total hip arthroplasty (THA) have gained popularity in recent years. We conducted a qualitative and systematic review to assess the effectiveness of MIS, CAS and computer-assisted MIS for THA.MethodsAn extensive computerised literature search of PubMed, Medline, Embase and OVIDSP was conducted. Both randomised clinical trials and controlled clinical trials on the effectiveness of MIS, CAS and computer-assisted MIS for THA were included. Methodological quality was independently assessed by two reviewers. Effect estimates were calculated and a best-evidence synthesis was performed.ResultsFour high-quality and 14 medium-quality studies with MIS THA as study contrast, and three high-quality and four medium-quality studies with CAS THA as study contrast were included. No studies with computer-assisted MIS for THA as study contrast were identified. Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA, with no difference in complication rates and risk for acetabular outliers. Strong evidence exists that there is no difference in physical functioning, measured either by questionnaires or by gait analysis. Moderate evidence was found for a shorter length of hospital stay after MIS THA. Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period, but that effect diminished after three months postoperatively. Strong evidence was found for an increase in operative time for CAS THA, and limited evidence was found for a decrease in intraoperative blood loss. Furthermore, strong evidence was found for no difference in complication rates, as well as for a significantly lower risk for acetabular outliers.ConclusionsThe results indicate that MIS THA is a safe surgical procedure, without increases in operative time, blood loss, operative complication rates and component malposition rates. However, the beneficial effect of MIS THA on functional recovery has to be proven. The results also indicate that CAS THA, though resulting in an increase in operative time, may have a positive effect on operative blood loss and operative complication rates. More importantly, the use of CAS results in better positioning of acetabular component of the prosthesis.

Subjects with hip osteoarthritis show distinctive patterns of trunk movements during gait-a body-fixed-sensor based analysis

BackgroundCompensatory trunk movements during gait, such as a Duchenne limp, are observed frequently in subjects with osteoarthritis of the hip, yet angular trunk movements are seldom included in clinical gait assessments. Hence, the objective of this study was to quantify compensatory trunk movements during gait in subjects with hip osteoarthritis, outside a gait laboratory, using a body-fixed-sensor based gait analysis. Frontal plane angular movements of the pelvis and thorax and spatiotemporal parameters of persons who showed a Duchenne limp during gait were compared to healthy subjects and persons without a Duchenne limp.MethodsA Body-fixed-sensor based gait analysis approach was used. Two body-fixed sensors were positioned at the dorsal side of the pelvis and on the upper thorax. Peak-to-peak frontal plane range of motion (ROM) and spatiotemporal parameters (walking speed, step length and cadence) of persons with a Duchenne limp during gait were compared to healthy subjects and persons without a Duchenne limp. Participants were instructed to walk at a self-selected low, preferred and high speed along a hospital corridor. Generalized estimating equations (GEE) analyses were used to assess group differences between persons with a Duchenne limp, without a Duchenne limp and healthy subjects.ResultsPersons with a Duchenne limp showed a significantly larger thoracic ROM during walking compared to healthy subjects and to persons without a Duchenne limp. In both groups of persons with hip osteoarthritis, pelvic ROM was lower than in healthy subjects. This difference however only reached significance in persons without a Duchenne limp. The ratio of thoracic ROM relative to pelvic ROM revealed distinct differences in trunk movement patterns. Persons with hip osteoarthritis walked at a significantly lower speed compared to healthy subjects. No differences in step length and cadence were found between patients and healthy subjects, after correction for differences in walking speed.ConclusionsDistinctive patterns of frontal plane angular trunk movements during gait could be objectively quantified in healthy subjects and in persons with hip osteoarthritis using a body-fixed-sensor based gait analysis approach. Therefore, frontal plane angular trunk movements should be included in clinical gait assessments of persons with hip osteoarthritis.

Habitual Physical Activity Behavior of Patients After Primary Total Hip Arthroplasty

Background and Purpose: Despite recognized health benefits of physical activity, little is known about the habitual physical activity behavior of patients after total hip arthroplasty (THA). The purpose of this study was to analyze this behavior and the fulfillment of guidelines for health-enhancing physical activity of these patients compared with a normative population. Subjects and Methods: The participants were 273 patients who had undergone a primary THA (minimum of 1 year postoperatively). Comparisons were made between this group and 273 age- and sex-matched individuals from a normative population. Comparisons also were made between participants with THA under 65 years of age and those 65 years of age and older and among participants with THA in different Charnley classes. Level of physical activity was assessed with the Short QUestionnaire to ASsess Health-enhancing physical activity (SQUASH). Results: No significant differences in total amount of physical activity or time spent in different categories of physical activity were found between the THA group and the normative group. Participants with THA spent significantly more minutes in activities of moderate intensity compared with the normative group. Participants with THA who were under 65 years of age were significantly more active than older participants with THA. Charnley class had significant effects on time spent at work, time spent in moderate-intensity activities, and total amount of activity, with the least activity performed by participants in Charnley class C. The guidelines were met by 51.2% of the participants with THA and 48.8% of the normative population. Female participants met the guidelines less frequently than male participants in both the combined groups (odds ratio=0.50, 95% confidence interval=0.35–0.72, P<.001) and the THA group (odds ratio=0.48, 95% confidence interval=0.28–0.80, P=.001). Discussion and Conclusion: The results suggest that patients after THA are at least as physically active as a normative population. Nevertheless, a large percentage of these patients do not meet the guidelines; therefore, they need to be stimulated to become more physically active.

Effectiveness of computer-navigated minimally invasive total hip surgery compared to conventional total hip arthroplasty: design of a randomized controlled trial

BackgroundModerate to severe osteoarthrosis is the most common indication for Total Hip Arthroplasty (THA). Minimally Invasive Total Hip Surgery (MIS) and computer-navigated surgery were introduced several years ago. However, the literature lacks well-designed studies that provide evidence of superiority of computer-navigated MIS over a conventional THA technique. Hence, the purpose of this study is to compare (cost)effectiveness of computer-navigated MIS with a conventional technique for THA. It is our hypothesis that computer-navigated MIS will lead to a quicker recovery during the early postoperative period (3 months), and to an outcome at least as good 6 months postoperatively. We also hypothesize that computer-navigated MIS leads to fewer perioperative complications and better prosthesis positioning. Furthermore, cost advantages of computer-navigated MIS over conventional THA technique are expected.Methods/designA cluster randomized controlled trial will be executed. Patients between the ages of 18 and 75 admitted for primary cementless unilateral THA will be included. Patients will be stratified using the Charnley classification. They will be randomly allocated to have computer-navigated MIS or conventional THA technique. Measurements take place preoperatively, perioperatively, and 6 weeks and 3 and 6 months postoperatively. Degree of limping (gait analysis), self-reported functional status and health-related quality of life (questionnaires) will be assessed preoperatively as well as postoperatively. Perioperative complications will be registered. Radiographic evaluation of prosthesis positioning will take place 6 weeks postoperatively. An evaluation of costs within and outside the healthcare sector will focus on differences in costs between computer-navigated MIS and conventional THA technique.DiscussionBased on studies performed so far, few objective data quantifying the risks and benefits of computer-navigated MIS are available. Therefore, this study has been designed to compare (cost) effectiveness of computer-navigated MIS with a conventional technique for THA. The results of this trial will be presented as soon as they become available.

Physical Activity Behavior of Patients 1 Year After Primary Total Hip Arthroplasty: A Prospective Multicenter Cohort Study

Background Besides the important beneficial effects of regular physical activity on general health, some of the musculoskeletal effects of physical activity are of particular interest for older adults after total hip arthroplasty (THA). However, research on physical activity behavior of patients after THA is scarce. Objective The purpose of this study was to gain insight into the physical activity behavior and fulfillment of guidelines for health-enhancing physical activity of patients 1 year after THA. Design This was a prospective multicenter cohort study. Methods To determine level of physical activity, 653 participants (response rate=77%) completed the Short QUestionnaire to ASsess Health-enhancing physical activity (SQUASH). Comparisons were made between participants in 2 age groups (≤75 and >75 years). Determinants of physical activity behavior were assessed. Results The participants were physically active a mean of 1,468 minutes per week. Most time was spent in household and leisure activities. Younger participants were physically more active than older participants. A lower body mass index was predictive of a higher level of physical activity. Participants adhered to the guidelines of health-enhancing physical activity in 67% of cases. The guidelines were met more often by younger participants, male participants, and those without problems in the lower extremities. Limitations A nonresponse analysis was not conducted; thus, there might have been a selection bias. Use of a self-administered recall questionnaire to assess physical activity behavior may have been subject to memory and recall skill limitations of the participants, and patients tend to overestimate their physical activity level. Conclusions This study gives detailed insight into the physical activity of patients 1 year after primary THA. As among the general population, a considerable number of patients were found to be insufficiently physically active.

Changes in Body Weight After Total Hip Arthroplasty: Short-term and Long-term Effects

Background Elevated body weight is associated with hip osteoarthritis (OA) and subsequently with total hip arthroplasty (THA). Patients with hip OA who are overweight often mention their restricted mobility as a factor that thwarts their attempts to be physically active and lose weight. There is some evidence that THA increases physical activity, but none for losing body weight after THA. Objective The purpose of this study was to analyze the short-term (1-year) and long-term (4.5-year) effects of a THA on body weight. Design This was an observational, multicenter cohort study. Methods For the short-term effect, all patients (N=618) were analyzed; for the long-term effect, a random subgroup (n=100) was analyzed. Preoperative and postoperative body weight and height were self-reported. Patients were categorized according to their preoperative body mass index (BMI <25 kg/m2=normal weight, 25–30 kg/m2=overweight, >30 kg/m2=obese). Clinical relevancy was set at a minimum of 5% weight loss compared with baseline. Results The mean age of the study group was 70 years (SD=8), 74% were women, and mean preoperative body mass was 79 kg (SD=14). One year after THA, a significant decrease in body weight of 1% and 3.4% occurred for the overweight and obese BMI categories, respectively. After 4.5 years, a significant decrease in body weight of 6.4% occurred for the obese BMI category. Limitations Height and weight—and thus BMI—were self-reported. Conclusion Patients in the overweight and obese groups showed a decrease, albeit not clinically relevant, in body weight after 1 year. After 4.5 years, a decrease that was relevant clinically was observed in the patients who were obese. It can be concluded that no clinically relevant reduction of weight occurred after THA, except in the long term for patients who were obese.

Comparison of Gait in Patients Following a Computer-Navigated Minimally Invasive Anterior Approach and a Conventional Posterolateral Approach for Total Hip Arthroplasty : A Randomized Controlled Trial

Minimally invasive total hip arthroplasty (MIS THA) aims at minimizing damage to muscles and tendons to accelerate postoperative recovery. Computer navigation allows a precise prosthesis alignment without complete visualization of the bony landmarks during MIS THA. A randomized controlled trial (RCT) was conducted to determine the effectiveness of a computer‐navigated MIS anterior approach for THA compared to a conventional posterolateral THA technique on the restoration of physical functioning during recovery following surgery. Thirty‐five patients underwent computer‐navigated MIS THA via the anterior approach, and 40 patients underwent conventional THA using the conventional posterolateral approach. Gait analysis was performed preoperatively, 6 weeks, and 3 and 6 months postoperatively using a body‐fixed‐sensor based gait analysis system. Walking speed, step length, cadence, and frontal plane angular movements of the pelvis and thorax were assessed. The same data were obtained from 30 healthy subjects. No differences were found in the recovery of spatiotemporal parameters or in angular movements of the pelvis and thorax following the computer‐navigated MIS anterior approach or the conventional posterolateral approach. Although gait improved after surgery, small differences in several spatiotemporal parameters and angular movements of the trunk remained at 6 months postoperatively between both patient groups and healthy subjects.

Physical Activity Participation Among Patients After Total Hip and Knee Arthroplasty

Total hip (THA) and knee arthroplasty (TKA) are successful operative interventions, yet little is known about the physical activity behavior of patients after THA/TKA. For older adults, there are beneficial effects of regular physical activity after THA/TKA. The objective of this paper is to review the benefits of physical activity after THA/TKA, the potential negative consequences of physical activity on hip or knee prosthesis, the measurement of physical activity, physical activity behavior, and the current opinion of health care professionals regarding types of physical activities recommended for patients after THA/TKA.

Compensatory Trunk Movements in Patients with Hip Osteoarthritis Accuracy and Reproducibility of a Body-Fixed Sensor-Based Assessment

This study examined the accuracy and reproducibility of a body‐fixed sensor‐based assessment for quantifying frontal plane angular movements of the (upper) thorax and pelvis of patients with hip osteoarthritis at different walking speeds. To evaluate accuracy, the angular movements of sensors attached to the thorax and pelvis of three patients were compared with results based on an optical motion analysis system. Accuracy was high, with small and consistent mean differences (<1.0 degree) and corresponding standard deviations (<1.3 degrees) between optical motion analysis system and body‐fixed sensor data. To evaluate reproducibility, angular trunk movements were assessed twice in 15 patients. Reproducibility was high (intraclass correlation coefficients ranged from 0.86 to 0.97), and the values of the mean differences between the test and retest were small, with the 95% confidence interval containing zero. This body‐fixed sensor‐based assessment is an accurate and reproducible method for quantifying frontal plane compensatory trunk movements during gait of patients with hip osteoarthritis at different walking speeds.