Biomedical subjects

Piet M Rozing

Publications and source records attributed to Piet M Rozing.

14 recordsLinked to original sources

PubMed2006

Model-based RSA of a femoral hip stem using surface and geometrical shape models.

Roentgen stereophotogrammetry (RSA) is a highly accurate three-dimensional measuring technique for assessing micromotion of orthopaedic implants. A drawback is that markers have to be attached to the implant. Model-based techniques have been developed to prevent using special marked implants. We compared two model-based RSA methods with standard marker-based RSA techniques. The first model-based RSA method used surface models, and the second method used elementary geometrical shape (EGS) models. We used a commercially available stem to perform experiments with a phantom as well as reanalysis of patient RSA radiographs. The data from the phantom experiment indicated the accuracy and precision of the elementary geometrical shape model-based RSA method is equal to marker-based RSA. For model-based RSA using surface models, the accuracy is equal to the accuracy of marker-based RSA, but its precision is worse. We found no difference in accuracy and precision between the two model-based RSA techniques in clinical data. For this particular hip stem, EGS model-based RSA is a good alternative for marker-based RSA.

Arthroplasty, Replacement, Hip↗

PubMed2006

Comparison of high-grade and low-grade mobilization techniques in the management of adhesive capsulitis of the shoulder: randomized controlled trial.

BACKGROUND AND PURPOSE: In many physical therapy programs for subjects with adhesive capsulitis of the shoulder, mobilization techniques are an important part of the intervention. The purpose of this study was to compare the effectiveness of high-grade mobilization techniques (HGMT) with that of low-grade mobilization techniques (LGMT) in subjects with adhesive capsulitis of the shoulder. SUBJECTS: One hundred subjects with unilateral adhesive capsulitis lasting 3 months or more and a > or =50% decrease in passive joint mobility relative to the nonaffected side were enrolled in this study. METHODS: Subjects randomly assigned to the HGMT group were treated with intensive passive mobilization techniques in end-range positions of the glenohumeral joint, and subjects in the LGMT group were treated with passive mobilization techniques within the pain-free zone. The duration of treatment was a maximum of 12 weeks (24 sessions) in both groups. Subjects were assessed at baseline and at 3, 6, and 12 months by a masked assessor. Primary outcome measures included active and passive range of motion and shoulder disability (Shoulder Rating Questionnaire [SRQ] and Shoulder Disability Questionnaire [SDQ]). An analysis of covariance with adjustments for baseline values and a general linear mixed-effect model for repeated measurements were used to compare the change scores for the 2 treatment groups at the various time points and over the total period of 1 year, respectively. RESULTS: Overall, subjects in both groups improved over 12 months. Statistically significant greater change scores were found in the HGMT group for passive abduction (at the time points 3 and 12 months), and for active and passive external rotation (at 12 months). A statistically significant difference in trend between both groups over the total follow-up period of 12 months was found for passive external rotation, SRQ, and SDQ with greater change scores in the HGMT group. DISCUSSION AND CONCLUSION: In subjects with adhesive capsulitis of the shoulder, HGMTs appear to be more effective in improving glenohumeral joint mobility and reducing disability than LGMTs, with the overall differences between the 2 interventions being small.

Bursitis↗

PubMed2005

Impact of adhesive capsulitis and economic evaluation of high-grade and low-grade mobilisation techniques.

The purpose of this study was to estimate the impact of adhesive capsulitis on costs and health and to compare the cost-utility of high-grade and low-grade mobilisation techniques. In a randomised controlled trial, 92 patients with adhesive capsulitis received either high-grade mobilisation techniques or low-grade mobilisation techniques and were followed for one year. Outcome measures were quality adjusted life years (QALYs) according to the Short Form 6D (SF-6D) and societal costs estimated from cost questionnaires. Estimated costs and QALYs in both randomisation groups were similar, except for the number of treatment sessions (18.6 for high-grade mobilisation techniques versus 21.5 for low-grade mobilisation techniques), with an estimated cost difference of 105 euros in favour of high-grade mobilisation techniques (p = 0.001, 95% CI 43 euros to 158 euros). In the entire sample, the average valuation of health improved from 0.597 at baseline to 0.745 after a year. The burden due to adhesive capsulitis was estimated at 0.048 QALY and 4,521 euros per patient. About half these costs were due to absenteeism which, during the first quarter, amounted to 38% of the total working hours. In conclusion, the cost-utility analysis does not allow for an evidence-based recommendation on the preferred treatment. Based on the clinical outcome measures, high-grade mobilisation techniques are still preferred to low-grade mobilisation techniques. The estimated substantial burden, both to the patient and to society, suggests that effective early treatment of adhesive capsulitis is warranted to attempt to accelerate recovery.

Bursitis↗

PubMed2005

Limited influence of prosthetic position on aseptic loosening of elbow replacements: 125 elbows followed for an average period of 5.6 years.

BACKGROUND: Aseptic loosening of elbow replacements, seen in long-term follow-up, remains a problem. In this study, we attempted to determine the influence of cementing technique, prosthetic position, different component sizes, use of a bone plug, and intraoperative fractures on the development and progression of radiolucent lines and aseptic loosening. METHODS: We studied standard radiographs of 125 primary Souter-Strathclyde total elbow prostheses using the Wrightington method. Additionally, 104 preoperative radiographs were available for analysis. We used a Markow statistical model to detect relationships between all factors described above. RESULTS: After a mean follow-up time of 5.5 (2-19) years, 21 (17%) prostheses had loosened radiographically (10-year survival: 65%). When the humeral component was tilted more medially or more anteriorly, we found development of radiolucent lines at the medial condyle and at the posterior side of the humeral component. However, the progression of these lines was not influenced by these positions. No other prognostic factors for radiolucent lines or aseptic loosening were found. INTERPRETATION: Despite the small number of elbows studied, the weak influence of prosthetic position on aseptic loosening gives more ground for a multifactorial cause for aseptic loosening of the Souter-Strathclyde total elbow prosthesis.

Adult↗

PubMed2005

Identifying error pathways during elbow and knee replacements.

The aim of our study was to identify errors and error pathways during joint replacements and to propose improvements. A time-action and error analysis method was adapted for use during surgery. The error analysis consisted of identifying all possible errors, determining error paths presented in an error chart, quantifying errors, and determining the impact of errors. This method was used to evaluate joint replacements. We evaluated five knee and 11 elbow replacements done by two experienced surgeons. The main error for elbow replacements was caused by inadequate instruments. The main error for knee replacements was caused by inexperienced nurses being unfamiliar with guiding instruments. The time-action analysis showed a large variation in procedure duration. The main surgical limitations for both procedures were waiting caused by the cementing process and waiting caused by inexperienced scrub nurses. Our study identified errors and surgical limitations during joint replacements by using time-action and error analysis. Placement of both prostheses will benefit from new fixation techniques, a more experienced nursing staff, and more organized instrument tables.

Arthroplasty, Replacement↗

PubMed2005

Quantitative assessment of fatty degeneration in rotator cuff muscles determined with computed tomography.

OBJECTIVES: Reliable assessment of fatty degeneration of rotator cuff muscles is desirable to predict the outcome of shoulder surgery. Currently used qualitative assessments are limited by relatively high inter- and intraobserver variability. It was hypothesized that a quantitative measurement of muscle density using computed tomography (CT) was more reliable and reproducible. MATERIALS AND METHODS: Thirty shoulders from patients with rheumatoid arthritis were analyzed using parasagittal multiplanar reconstructions acquired from a 16-slice CT scanner. Three observers visually rated the severity of fatty degeneration and independently outlined the rotator cuff muscles, after which the mean density was calculated. Inter- and intraobserver agreement on both measurements was expressed by the interclass correlation coefficient (ICC) and the standard deviation of the differences (SDD) between the measurements. RESULTS: A strong correlation was found between the quantitative measure and the visual rating (R2 = 0.94; P < 0.0001). The SDD in muscle density did not exceed 2.3 Hounsfield units, and the mean rotator cuff ICC (0.98) was substantially greater than that of the visual rating (0.63). CONCLUSIONS: This study describes a reproducible method to quantify fatty degeneration of the rotator cuff muscles in CT images, with a higher interobserver agreement than the visual score, and may prove a reliable tool to evaluate the quality of the rotator cuff muscles.

Adipose Tissue↗

PubMed2005

Translation, adaptation and validation of the Shoulder Rating Questionnaire (SRQ) into the Dutch language.

OBJECTIVE: To translate and adapt the original English version of the Shoulder Rating Questionnaire (SRQ) into the Dutch language (SRQ-DLV) and evaluate its internal consistency, reliability, validity and responsiveness to clinical changes. DESIGN: Prospective study. SETTING: Outpatient departments of orthopaedics, radiology and physical therapy of an academic and a non-academic hospital. SUBJECTS: One hundred and seven patients treated for unilateral shoulder disorder (adhesive capsulitis 68, calcifying tendinitis 22, impingement syndrome or rotator cuff tear 17). METHODS: The original SRQ was translated and adapted following international guidelines. The SRQ-DLV was used among other measures of body function and structure, activities and societal participation in order to determine reliability, internal consistency, validity and responsiveness. Assessments were done at baseline and three months after treatment, with the SRQ-DLV being re-administered within one week before the baseline measurement and the start of the treatment for testing reliability. RESULTS: Cronbach's alpha for internal consistency was 0.89 for the total questionnaire and 0.81, 0.80, 0.72 and 0.84 for the domains pain, daily activities, sports/recreational activities and work, respectively. Test-retest reliability of the SRQ-DLV and its subscales ranged from 0.63 to 0.86. The summary score of the SRQ-DLV correlated with measures of shoulder function, daily activities and quality of life. Except for the work subscale of the SRQ-DLV, large effect sizes, reflecting its responsiveness to clinical changes after treatment, were found for both the summary and the subscales scores. CONCLUSIONS: Empirical data support that the SRQ-DLV is a reliable, valid and responsive measure to be used in clinical trials including Dutch patients with various shoulder disorders.

Disability Evaluation↗

PubMed2005

Factors influencing the surgical process during shoulder joint replacement: time-action analysis of five different prostheses and three different approaches.

BACKGROUND: To evaluate the per-operative process of shoulderjoint replacement, time-action analysis can be used. MATERIAL/METHODS: Forty procedures performed by 7 surgeons with different experience using 5 different prostheses and 3 different surgical approaches were analyzed. RESULTS: The surgical procedures showed a large variation in, for example, duration, tasks of team members, and protocol used. The surgical procedure was influenced by several factors, such as the prosthesis used, the surgical approach, the patient's condition, and the experience of the surgeon. Exposure of the glenoid was difficult and several retractors were needed, which were held by an extra assistant or clamped to the table or the surgeon. Two main limitations were seen in all procedures: repeated actions and waiting. Also, five errors could be identified. None of the alignment instruments was completely reliable and they allowed the surgeon to make major errors. CONCLUSIONS: Better alignment instruments, pre-operative planning techniques, and operation protocols are needed for shoulder prostheses. The training of resident surgeons should be focused on the exposure phase, the alignment of the humeral head, the exposure of the glenoid, and the alignment of the glenoid. Evaluating the surgical process using time-action analysis can be used to determine the limitations during surgical procedures. Furthermore, it shows the large variation in factors affecting surgical performance, indicating that a system approach is needed to improve surgical outcome.

Arthroplasty, Replacement↗

PubMed2004

Reliability of force direction dependent EMG parameters of shoulder muscles for clinical measurements.

OBJECTIVE: To assess the reliability of force direction dependent EMG parameters in shoulder muscles for future clinical research. DESIGN: EMG measurements of shoulder muscles including the rotator cuff were performed during isometrical external loading in various directions covering 360 degrees in a plane perpendicular to the humeral axis. BACKGROUND: Relating EMG to force direction bypasses problems associated with the unknown position and velocity dependence of the EMG signal. For clinical application, information on the reliability of force direction dependent parameters is required. METHODS: The EMG of shoulder muscles of healthy subjects was related to force direction. The activation patterns obtained where parameterised after least squares function fitting, returning three force direction dependent parameters, i.e. two on- and offset directions of the activity peak and the direction of highest EMG activity also called principal action. Within-trial, inter-trial, inter-day and inter-subject variabilities were estimated. RESULTS: With a group size of n = 10, the 95% confidence interval for inter-day measurements was found to be about +/-5 degrees on a scale of 360 degrees for the principal action and just below +/-10 degrees for the intercepts. CONCLUSION: The method allows for intra-individual measurements on different days with sufficient accuracy so that shoulder muscle co-ordination of patients before and after interventions like surgery or physical therapy can be evaluated. RELEVANCE: Quantitative data on shoulder muscle function in vivo are required to assess the effectiveness of interventions on the shoulder.

Adult↗

PubMed2002

The size of the supraspinatus outlet during elevation of the arm in the frontal and sagittal plane: a 3-D model study.

OBJECTIVE: To quantify the size of the supraspinatus outlet as it is dictated by both the three-dimensional geometry of the shoulder and the relative orientation of the humerus with respect to the scapula during motions of the arm. DESIGN: Previously obtained data of shoulder kinematics were brought into a geometrical model of the shoulder, derived from a cadaver study. BACKGROUND: Knowledge of the parameters dictating the size of the supraspinatus outlet is essential for a better understanding of the impingement syndrome of the shoulder. METHODS: A geometrical model, based on fitting spheres to various anatomical items of the shoulder was derived from three-dimensional position data of the gleno-humeral joint and coraco-acromial arch of 32 cadaver shoulders. Kinematical data were collected from 10 healthy volunteers. The geometrical and kinematical data were combined to study the supraspinatus outlet during elevation of the humerus in the frontal and sagittal plane. RESULTS: No single geometry parameter correlated significantly with the initial size of the outlet. During arm elevation, the greater tuberosity was moved away from the coraco-acromial arch quite effectively resulting in narrowing of the outlet during elevation in the frontal plane from 60 degrees to 120 degrees only. Deviations from the average were quite substantial. This was caused by kinematical and especially geometrical variability. CONCLUSION: The size of the outlet is dictated by both the geometry and kinematics of the gleno-humeral joint. Assessment of the individual susceptibility to impingement requires three-dimensional viewing techniques including three-dimensional movements of both the scapula and humerus. RELEVANCE: Little is known about etiology and pathogenesis of various shoulder disorders such as the impingement syndrome. The supraspinatus outlet plays probably a key role. More knowledge on the architecture of the outlet is required for a better understanding.

Acromioclavicular Joint↗

PubMed2002

Micromotion of the Souter-Strathclyde total elbow prosthesis in patients with rheumatoid arthritis 21 elbows followed for 2 years.

21 elbows in 18 patients with rheumatoid arthritis were treated with a Souter-Strathclyde total elbow prosthesis. 18 elbows were included in a radiostereometry (RSA) study. The aim of this clinical RSA study was to assess the three-dimensional micromotion pattern of the Souter-Strathclyde prosthesis, and thereby gain insight in the aseptic loosening process of this prosthesis. Implants were defined as at risk of aseptic loosening when the translation rate during the second postoperative year was more than 0.4 mm along one or more coordinate axes and/or the rate of rotation was more than 1 degrees about one or more coordinate axes. Clinical examination revealed an increase in the range of motion and a marked reduction in pain. The RSA showed that 8 of 18 humeral components were at risk of aseptic loosening, although no signs of such loosening-defined as a complete radiolucent line of 2 mm or more-were found on the plain radiographs. In 7 humeral components, an anterior tilt about the transverse axis was seen that resulted in an anterior translation of the proximal tip and a posterior translation of the component's trochlea. Long-term studies of the Souter-Strathclyde prosthesis, have shown that this rotation is a specific pattern of failure in some implants. None of the ulnar components was at risk for aseptic loosening. Improvements in fixation of the Souter-Strathclyde total elbow arthroplasty should focus on the humeral component. At present, the lateral flange of the implant is enlarged to improve rotational stability about the transverse and longitudinal axes. The effect of this change in design on micromotion of the Souter-Strathclyde total elbow prosthesis will be studied in a randomized RSA study comparing the new design to the existing one.

Aged↗

PubMed2002

Biomechanical evaluation of the elbow using roentgen stereophotogrammetric analysis.

The medial collateral ligament complex is the primary constraint of the elbow to valgus forces and is composed of the anterior bundle, the posterior bundle, and a transverse part. Total and partial ruptures have been described. Clinical and radiologic examinations of medial or valgus instability of the elbow are difficult. The effect of different stages of medial collateral ligament ruptures on ulnohumeral movement in cadavers was determined to rationalize the use of physical and radiologic examinations in different stages of valgus instability in vivo. Using roentgen stereophotogrammetric analysis, motion is determined between the humerus and ulna under valgus load and between the humerus and radius during maximal pronation of the forearm after various dimensions of medial collateral ligament lesions. The increase in distance between the humerus and ulna under a 15 N valgus load varied from 2.7 mm to 9.8 mm. The increase in distance between the humerus and proximal radius with the forearm in pronation in an intact specimen and after transsection of the anterior medial collateral ligament and posterior medial collateral ligament in the anterior direction was 9.7 mm. These results suggest that detection of partial ruptures with clinical and radiologic examinations is difficult. Anterior movement of the radial head can be used as an additional parameter of valgus instability.

Aged↗

PubMedDate not supplied

Evaluation of humeral head replacements using time-action analysis.

New surgical technologies are often introduced without objective evaluation of their efficiency. Commonly, their results are only related to surgical outcome and complication rate. In this study, time-action analysis was applied to evaluate the per-operative process and to measure surgical performance during 8 humeral head replacements. An overview of the operative theater and a detailed view were recorded on video simultaneously. The duration and number of actions grouped to functions, limitations, and repeated actions were determined. The duration and number of performed actions varied between procedures. The efficiency of the procedure, defined as the percentage of goal-oriented functions, was about 55%. Repeated actions were frequently observed during the alignment and insertion phase. We conclude that time-action analysis can be used to evaluate surgical performance objectively. Limitations of the surgical process that can be improved could be identified. These findings enable the evaluation of new operative techniques, protocols, and instruments.

Arthroplasty, Replacement↗

PubMedDate not supplied

Stress shielding and bone resorption in shoulder arthroplasty.

The radiographs of 64 patients with 70 humeral head replacements were reviewed for signs of stress shielding. Of these, 49 were implanted for rheumatoid arthritis and 21 for osteoarthritis. The radiographic follow-up averaged 5.3 years. Measurements of cortex thickness were performed in 4 regions along the stem of the implant, and the differences between the postoperative radiograph and the radiograph at follow-up were calculated. The size of the stem in relation to the diameter of the humerus was calculated with the use of validated measures, resulting in the relative stem size. In 6 patients (9%) a significant reduction in cortical thickness was observed in the proximal-lateral region of the humeral stem, 5 in rheumatoid patients and 1 in an osteoarthritic patient. In the stress shielding group, the relative stem size was found to be significantly higher than that in the non-stress shielding group (0.58 vs 0.48). Osteoporosis, especially present in rheumatoid arthritis, could well be a risk factor. It was concluded that stress shielding is a long-term complication of shoulder arthroplasty and that the relative stem size is an important factor in its genesis.

Adaptation, Physiological↗