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Henk van Mameren

Publications and source records attributed to Henk van Mameren.

14 recordsLinked to original sources
PubMed2006

Stapedius muscle fiber characterization during postnatal development in the rat.

The stapedius muscle (SM) is reported to prevent cochlear damage by noise. Functional demands are then the ability of fast contraction with long endurance. At the end of the third postnatal week, the middle ear of the rat is completely pneumatized and according to electrophysiological data, the auditory function starts to match the adult. We investigated the developmental changes in myosin composition of SM fibres using consecutive complete SM cross-sections (taken from rats on post natal day (PND) 7, 14, 16, 21, 28, 42 and 84) which were processed by enzymehistochemistry to determine acid/alkali lability of myofibrillar adenosine triphosphatase (mATPase) and by immunohistochemistry using myosin heavy chain (MHC) antibodies (mAb). Fibres were assigned to mATPase type I, IIA, IIB, IIX or 'Miscellaneous' categories. Per mATPase category, the fibres were attributed to groups with specific MHC isoform compositions. Neonatal MHC expression could not be documented with the mAb used. However, embryonal (Emb) MHC was expressed at PND 7, very little at PND 14; at later PND fibres did not show Emb MHC. In general, the mATPase-based classification did not show large alterations after PND 21. Expression of MHC IIB, which was present in almost 50% of the fibres at PND 7 and 14, diminished to 3% at PND 84. A decrease in number of fibres expressing more than one MHC isoform was found. These results show that the SM is a precociously developing muscle compared to limb muscles and even to the diaphragm. Moreover, it is shown that the expression of the adult MHC isoform phenotype coincides with the onset of auditory function in the third postnatal week.

Adenosine Triphosphatases↗
PubMed2006

Manual therapy, physical therapy, or continued care by the general practitioner for patients with neck pain: long-term results from a pragmatic randomized clinical trial.

OBJECTIVES: The authors' goals were to compare the effectiveness of manual therapy (MT; mainly spinal mobilization), physical therapy (PT; mainly exercise therapy), and continued care by the general practitioner (GP; analgesics, counseling and education) over a period of 1 year. METHODS: One hundred eighty-three patients suffering for at least 2 weeks from nonspecific neck pain were randomized to receive a 6-week treatment strategy of MT once a week, PT twice a week, or GP care once every 2 weeks. The primary outcome measures were perceived recovery, severity of physical dysfunctioning, pain intensity, and functional disability. RESULTS: The differences between groups considered over 1 year were statistically significant (repeated measurements analyses P<0.001 to P=0.02) for all outcomes but borderline for the Neck Disability Index (P=0.06). Higher improvement scores were observed for MT for all outcomes, followed by PT and GP care. The success rate, based on perceived recovery after 13 weeks, was 72% for MT, which was significantly higher than the success rate for continued GP care (42%, P=0.001) but not significantly higher compared with PT treatment (59%, P=0.16). The difference between PT and GP approached statistical significance (P=0.06). After 1 year the success rates were 75%, 63%, and 56%, respectively, and no longer significantly different. CONCLUSIONS: Short-term results (at 7 weeks) have shown that MT speeded recovery compared with GP care and, to a lesser extent, also compared with PT. In the long-term, GP treatment and PT caught up with MT, and differences between the three treatment groups decreased and lost statistical significance at the 13-week and 52-week follow-up.

Adolescent↗
PubMed2005

Reproducibility of cervical range of motion in patients with neck pain.

BACKGROUND: Reproducibility measurements of the range of motion are an important prerequisite for the interpretation of study results. The aim of the study is to assess the intra-rater and inter-rater reproducibility of the measurement of active Range of Motion (ROM) in patients with neck pain using the Cybex Electronic Digital Inclinometer-320 (EDI-320). METHODS: In an outpatient clinic in a primary care setting 32 patients with at least 2 weeks of pain and/or stiffness in the neck were randomly assessed, in a test- retest design with blinded raters using a standardized measurement protocol. Cervical flexion-extension, lateral flexion and rotation were assessed. RESULTS: Reliability expressed by the Intraclass Correlation Coefficient (ICC) was 0.93 (lateral flexion) or higher for intra-rater reliability and 0.89 (lateral flexion) or higher for inter-rater reliability. The 95% limits of agreement for intra-rater agreement, expressing the range of the differences between two ratings were -2.5 +/- 11.1 degrees for flexion-extension, -0.1 +/- 10.4 degrees for lateral flexion and -5.9 +/- 13.5 degrees for rotation. For inter-rater agreement the limits of agreement were 3.3 +/- 17.0 degrees for flexion-extension, 0.5 +/- 17.0 degrees for lateral flexion and -1.3 +/- 24.6 degrees for rotation. CONCLUSION: In general, the intra-rater reproducibility and the inter-rater reproducibility were good. We recommend to compare the reproducibility and clinical applicability of the EDI-320 inclinometer with other cervical ROM measures in symptomatic patients.

Adult↗
PubMed2005

Do students have sufficient knowledge of clinical anatomy?

INTRODUCTION: Comparisons of anatomy knowledge levels of students from various curricula show either no differences or small differences to the detriment of innovative schools. To pass judgement on the general level of students' anatomy knowledge, we need an absolute standard. The purpose of this study was to compare students' levels of anatomy knowledge as measured by a case-based anatomy test with standards set by different groups of experts. METHODS: A modified Angoff procedure was used to establish an absolute standard against which the students' results could be evaluated. Four panels of 9 anatomists, 7 clinicians, 9 recent graduates and 9 Year 4 students, respectively, judged 107 items of an anatomy test. The students' results on these items were compared with the standards obtained by the panels. RESULTS: If the standard established by the panel of Year 4 students was used, 64% of the students would fail the test. The standards established by the anatomists, clinicians and recent graduates would yield failure rates of 42%, 58% and 26%, respectively. CONCLUSION: According to the panels' standards, many students did not know enough about anatomy. The high expectations that the Year 4 students appeared to have of their peers may contribute to students' uncertainty about their level of anatomy knowledge.

Anatomy↗
PubMed2005

The intermetatarsal and metatarsal declination angles: geometry as a source of error.

BACKGROUND: The measurements on radiographs of the foot are believed to give an objective impression of foot deformities. In patient management, the outcome of these measurements is one of the factors that the physician takes into consideration. In fact, the radiograph is a projection of three-dimensional structures and is as such liable to a certain amount of distortion. To our knowledge this distortion has not been quantified, although it seems important for the interpretation of the measurements. METHODS: First, mathematical models based on the geometry of standard anteroposterior and lateral radiographs were constructed and analyzed. Then, we simulated radiography with these models on three-dimensional data of metatarsals originating from CT scans of 10 normal volunteers. RESULTS: The distortion of the declination angles of the metatarsals was practically negligible. The intermetatarsal angles were distorted up to 5.4 degrees. The measured angles underestimated the three-dimensional angles. CONCLUSIONS: In interpreting the measurements of the metatarsal declination angles, distortion was not a factor. For intermetatarsal angles variability of distortion was only about one third of the reported interobserver variability, but it may have cumulative effects on the error of measured intermetatarsal angles. Moreover, the theoretical models predicted larger distortions in patients with deformities. In interpretation of angular measurements the physician should be aware of these pitfalls.

Adult↗
PubMed2005

Plantar pressure and sole thickness of the forefoot.

BACKGROUND: Based on earlier observations that the forefoot bears the highest plantar pressure at its center, the existence of a functional distal transverse arch in normal feet was denied, and plantar pressure was defined as merely the outcome of loading, surface area, and soft tissue. Although plantar pressure drives the changes in the foot, neither the position nor the behavior of the metatarsals during loading can be derived from plantar pressure alone. In light of this, our goal was to describe the changes in thickness in the sole and the corresponding plantar pressure during loading of the foot. METHODS: We used CT to image the foot of 10 subjects in four postures that were chosen to imitate four phases in the walking cycle. Before imaging we also recorded the plantar pressure with a pressure measuring insole on which the subjects were standing. From the data, the minimal thickness of the sole and the corresponding plantar pressure were derived. RESULTS: With the exception of the sesamoids, the thickness of the sole under the bones of the forefoot increased from lateral to medial. This persisted in all postures. Our pressure readings matched previously reported distributions. CONCLUSIONS: Depending on the point of view concerning the sesamoids, the bony prominences were placed in a geometrical arch; but they did not form a functional arch. The soft tissue underneath the heads kept the metatarsals in place; the soft-tissue thickness reflected the principle of adequate cushioning.

Adult↗
PubMed2004

The interexaminer reproducibility of physical examination of the cervical spine.

OBJECTIVE: To assess the interexaminer reproducibility of physical examination of the cervical spine. METHODS: Two physiotherapists independently judged the general mobility and the intersegmental mobility (segments C0-T2) of the neck and the pain that was provoked. Percentage agreement and Cohen's kappa expressed agreement of dichotomous variables; limits of agreement expressed agreement of continuous variables; and intraclass correlation coefficients (ICCs) expressed the reliability of continuous variables. RESULTS: Agreement for general mobility showed kappa between 0.05 and 0.61, and for the intersegmental mobility, it showed kappa values between -0.09 and 0.63. Agreement for provoked neck pain within 1 point of an 11-point numerical rating scale (NRS) varied between 46.9% and 65.7% for general mobility and between 40.7% and 75.0% for intersegmental mobility. The ICCs varied between 0.36 and 0.71 for general mobility and between 0.22 and 0.80 for intersegmental mobility. CONCLUSIONS: Despite the use of a standardized protocol to assess general mobility and intersegmental mobility of the cervical spine, it is difficult to achieve reasonable agreement and reliability between 2 examiners. Likewise, the patients are not able to score the same level of provoked pain in 2 assessments with an interval of 15 minutes.

Adult↗
PubMed2003

Does problem-based learning lead to deficiencies in basic science knowledge? An empirical case on anatomy.

INTRODUCTION: Problem-based learning (PBL) is supposed to enhance the integration of basic and clinical sciences. In a non-integrative curriculum, these disciplines are generally taught in separate courses. Problem-based learning students perceive deficiencies in their knowledge of basic sciences, particularly in important areas such as anatomy. Outcome studies on PBL show controversial results, sometimes indicating that medical students at PBL schools have less knowledge of basic sciences than do their colleagues at more traditional medical schools. We aimed to identify differences between PBL and non-PBL students in perceived and actual levels of knowledge of anatomy. METHODS: Samples of Year 4 students in all eight medical schools in the Netherlands completed a questionnaire on perceived knowledge and took part in a computerised anatomy test consisting of both clinically contextualised items and items without context. RESULTS: Problem-based learning students were found to have the same perceived level of anatomy knowledge as students at other medical schools. Differences in actual levels of knowledge were found between schools. No significant effects on knowledge levels were found for PBL schools versus non-PBL schools. CONCLUSION: The results of this study show that PBL does not result in a lower level of anatomy knowledge than more traditional educational approaches. It remains to be ascertained whether the levels students attain are adequate. Subjects for further study are the desired level of anatomy knowledge at the end of undergraduate medical education and the effectiveness of basic science learning within a clinical context and with repetition over the course of the curriculum.

Adult↗
PubMed2003

The relationship of the position of the metatarsal heads and peak plantar pressure.

We test the premise that peak plantar pressure is located directly under the bony prominences in the forefoot region. The right foot of standing volunteers was examined in three different postures by a CT-scanner. The plantar pressure distribution was simultaneously recorded. The position of the metatarsal heads and the sesamoids could be related to the corresponding local peak plantar pressures. The metatarsal heads 1, 4, and 5 had a significantly different position than the local peak plantar pressures. The average difference in distance between the position of the metatarsal heads and the peak plantar pressure showed a significant correlation: on the medial side the head was located more distally to the local peak plantar pressure, on the lateral side more proximally. The findings suggest that normal plantar soft tissue is able to deflect a load. The observations might improve insight into the function of the normal forefoot and might direct further research on the pathological forefoot and on the design of footwear.

Adult↗
PubMed2002

Manual therapy, physical therapy, or continued care by a general practitioner for patients with neck pain. A randomized, controlled trial.

BACKGROUND: Neck pain is a common problem, but the effectiveness of frequently applied conservative therapies has never been directly compared. OBJECTIVE: To determine the effectiveness of manual therapy, physical therapy, and continued care by a general practitioner. DESIGN: Randomized, controlled trial. SETTING: Outpatient care setting in the Netherlands. PATIENTS: 183 patients, 18 to 70 years of age, who had had nonspecific neck pain for at least 2 weeks. INTERVENTION: 6 weeks of manual therapy (specific mobilization techniques) once per week, physical therapy (exercise therapy) twice per week, or continued care by a general practitioner (analgesics, counseling, and education). MEASUREMENTS: Treatment was considered successful if the patient reported being "completely recovered" or "much improved" on an ordinal six-point scale. Physical dysfunction, pain intensity, and disability were also measured. RESULTS: At 7 weeks, the success rates were 68.3% for manual therapy, 50.8% for physical therapy, and 35.9% for continued care. Statistically significant differences in pain intensity with manual therapy compared with continued care or physical therapy ranged from 0.9 to 1.5 on a scale of 0 to 10. Disability scores also favored manual therapy, but the differences among groups were small. Manual therapy scored consistently better than the other two interventions on most outcome measures. Physical therapy scored better than continued care on some outcome measures, but the differences were not statistically significant. CONCLUSION: In daily practice, manual therapy is a favorable treatment option for patients with neck pain compared with physical therapy or continued care by a general practitioner.

Adolescent↗
PubMed2002

Muscle fiber type IIX atrophy is involved in the loss of fat-free mass in chronic obstructive pulmonary disease.

BACKGROUND: Although the loss of peripheral muscle mass has been shown convincingly in chronic obstructive pulmonary disease (COPD), the underlying pathogenesis remains unclear. OBJECTIVE: The aim of the present study was to determine the relations between skeletal muscle fiber types, fiber cross-sectional area (CSA), enzyme activities, and fat-free mass (FFM) in patients with COPD and in control subjects. DESIGN: In 15 patients with COPD and 15 healthy, age-matched control subjects, FFM was determined by dual-energy X-ray absorptiometry and bioelectrical impedance analysis. In biopsy specimens from the vastus lateralis fiber types, fiber CSA and activities of cytochrome oxidase (EC 1.9.3.1), succinate dehydrogenase (EC 1.3.99.1), and glycogen phosphorylase (EC 2.4.1.1) were examined immunohistochemically and histochemically. RESULTS: Compared with control subjects, patients with COPD had less FFM (49 compared with 59 kg, P = 0.030) and lower mean fiber CSA (3839 compared with 4647 microm(2), P = 0.037). A strong correlation (r = 0.87, P < 0.001) was observed between the FFM measured by bioelectrical impedance analysis and mean fiber CSA in patients with COPD. Within fiber-type categories the mean CSA of only the IIA/IIX and IIX fiber types was lower in patients than in control subjects [3358 compared with 4428 microm(2) (P = 0.022) and 2566 compared with 4248 microm(2) (P = 0.003), respectively]. In COPD, 20% of the type IIX fibers lacked stainable activities of cytochrome oxidase, succinate dehydrogenase, and glycogen phosphorylase, and this proportion correlated negatively with type IIX fiber CSA (r = -0.65, P = 0.012). CONCLUSIONS: Muscle fiber atrophy occurs in the vastus lateralis in patients with COPD and contributes to the loss of muscle mass in COPD. Atrophy is specific to fiber types IIA/IIX and IIX and is associated with a disturbed metabolic capacity.

Aged↗
PubMed2002

The paper grip test for screening on intrinsic muscle paralysis in the foot of leprosy patients.

Plantar intrinsic foot muscles provide structure to the foot during walking and thus regulate mechanical foot sole stresses. When paralyzed, for instance in leprosy patients with neuropathy of the distal part of the tibial nerve, there is a high prevalence of plantar ulceration and deformities, especially when muscle weakness goes together with loss of foot sole sensibility. These patients should get immediate care involving education, special footwear and reconstructive surgery before further foot impairment and deformity becomes manifest. Thus far, in leprosy patients little attention is paid to screening of plantar intrinsic muscles activity. This can be done with a new simple and non-invasive method, the Paper Grip Test (PGT). There are two variants for detecting intrinsic muscle weakness of the foot, PGT1 for the great toe and PGT2 for the combined lesser toes. In this study, 517 leprosy patients and 170 healthy volunteers were investigated with the PGT. Sensibility of the foot sole was tested by means of a 10 gram monofilament. Specificity to the PGT1 is found to be about 95.3% which is considered good for physical diagnostic tests. PGT2 is less specific than PGT1. Individual muscle power and understanding of the patient seems to influence the outcome of the test to a certain extent. Sensitivity can only be calculated when the diagnosis is confirmed by electromyography. Especially patients with anesthetic feet, females, older patients and patients with PN-, BB- or LL-types of leprosy appeared to have a higher prevalence of intrinsic foot muscle weakness. All results were analyzed by means of the bivariate Pearson correlation-analysis and proved to be statistically significant (p = < 0.05). It is concluded that the PGT1, more than the PGT2, is a useful screening test on the function of plantar intrinsic foot muscles in leprosy patients in hospitals and during fieldwork in developing countries.

Adult↗
PubMedDate not supplied

Effect of tube angulation on the measurement of intermetatarsal angles.

We systematically investigated the effect of tube angulation on angular distortion of the anteroposterior radiograph of the foot. Three-dimensional data from the metatarsals originating from computed tomographic scans of ten healthy volunteers were projected onto the supporting surface at various tube angulations to simulate radiography. The distortion of the intermetatarsal angles decreased from 1.2 degrees to 3.5 degrees at 20 degrees tube angulation to 0.4 degrees to 2.7 degrees at 0 degrees tube angulation. The relatively small improvement in angular measurement using 0 degrees instead of 15 degrees tube angulation would not outweigh the adverse effects of changing the standard radiographic technique. Physician awareness of this source of error when planning surgical therapy seems more important.

Adult↗