Biomedical subjects

Jari P A Arokoski

Publications and source records attributed to Jari P A Arokoski.

12 recordsLinked to original sources

PubMed2006

Low metacarpal index predicts hip fracture: a prospective population study of 3,561 subjects with 15 years of follow-up.

BACKGROUND: Metacarpal index (MCI), measured from hand radiographs as the ratio between combined cortical thickness and bone diameter, has been suggested for assessment of bone mass and risk of osteoporotic fracture. We studied MCI for its ability to predict hip fractures. METHODS: Hand radiographs were taken and MCI determined in 3,561 subjects from a representative population sample of 8,000 Finns who were 30 years of age or over in 1978-80. Record linkage to the National Hospital Discharge Register identified 117 subjects who had been hospitalized for primary treatment of hip fracture by the end of 1994. RESULTS: High age, low body mass index, tall stature and smoking at baseline showed, independently of each other, significant associations with low MCI. Low MCI was a strong predictor of hip fracture. When adjusted for all potential confounding factors, the relative risk of hip fracture per decrement of MCI by one standard deviation (0.1) was 1.5 (95% CI 1.2-1.8). INTERPRETATION: Low MCI is associated with known risk factors of osteoporosis and predicts hip fracture. Since hand radiographs are easily available at low cost, measurements of MCI can be used as an alternative approach to find osteoporotic individuals with a high risk of hip fracture.

Absorptiometry, Photon↗

PubMed2006

The effect of small doses of botulinum toxin a on neck-shoulder myofascial pain syndrome: a double-blind, randomized, and controlled crossover trial.

OBJECTIVES: Myofascial pain syndrome is a common cause of muscular pain in the shoulder-neck region. Injections of large amounts of botulinum toxin A have been found to be beneficial for the alleviation of myofascial pain, but large doses of this toxin may cause paresis of the muscle and other adverse events. The aim of this work was to determine the effect of small doses (5 U) of botulinum toxin A (BTA) injected directly into the painful trigger points of the muscles, using a double-blind crossover technique. METHODS: On the basis of the empirical criteria proposed for diagnosis of myofascial pain syndrome, 31 patients suffering from myofascial pain in the neck-shoulder region were studied. The patients received either botulinum toxin A or physiological saline injections on 2 occasions 4 weeks apart. The total dose varied from 15 to 35 U of botulinum toxin A [28+/- 6 U (mean+/- SD)]. The follow-up measurements were carried out at 4 weeks after each treatment. Neck pain and result of treatment were assessed with questionnaires. The pressure pain threshold was determined using a dolorimeter. RESULTS: Neck pain values decreased from 4.3+/- 2.4 to 3.3+/- 2.0 after saline injections and from 4.1+/- 2.1 to 3.3+/- 2.2 after botulinum toxin A. The pressure pain threshold values increased from 5.2+/-1.6 to 5.9+/-1.5 and from 5.7+/-1.6 to 5.9+/-1.6 after injections with saline and botulinum toxin A, respectively. No statistically significant changes in the neck pain and pressure pain threshold values occurred between the botulinum toxin A and saline groups. After the first injections, the subjective result of treatment was significantly (P=0.008) in favor of botulinum toxin A, and after the second injections, the subjective result was better for saline, but the difference was not statistically significant (P=0.098). There was no significant difference in the prevalence of side effects between saline and botulinum toxin A. CONCLUSIONS: Our study shows that there was no difference between the effect of small doses of botulinum toxin A and those of physiological saline in the treatment of myofascial pain syndrome.

Adult↗

PubMed2005

Wireless on-line electromyography in recording neck muscle function: a pilot study.

AIM: The surface electromyography (SEMG) records muscle activity without causing pain and therefore it can be used in the on-line kinetic evaluation of rehabilitation methods. The cables are a problem in the clinical work. The aim of this pilot study was to introduce a wireless on-line SEMG method in the measurements of neck muscle activity and preliminarily evaluate its usability in dynamic exercises in a healthy and a neck pain subject. METHOD: The bilateral wireless on-line SEMG measurements were performed at the level C4-C5 of the cervical spine. The subjects (one healthy 32-year-old female and one neck pain patient, 35-year-old female) were performing slow cervical flexions with eyes open. The angle of the flexion was measured with inclinometer. RESULTS: In healthy subjects, the SEMG curve demonstrated clear flexion-relaxation rhythm whereas in the patient the rhythm was blurred. The SEMG signal quality was, however, good in both cases. CONCLUSION: Wireless on-line SEMG method seems promising in daily clinical work for the measurements of neck muscle activity.

Journal Article↗

PubMed2005

Feasibility of the use of a novel soft tissue stiffness meter.

Simple but objective measurement of soft tissue consistency would be advantageous in the assessment of many neurological, lymphostatic and venous disorders. The aim of the present study was to evaluate the feasibility of using a novel hand-held computerized soft tissue stiffness meter (STSM). The STSM describes the soft tissue stiffness (STS) in the form of the instantaneous force (N) by which the tissue resists the constant deformation produced by a cylindrical intender. Firstly, the STSM was used to test elastomer samples with known mechanical properties. In the in vivo assessment, 12 healthy, nondisabled adults (age range, 24-57 years) and 16 subjects with chronic myofascial neck pain syndrome (age range, 27-55 years) were studied. To study the reproducibility (coefficient of variation (CV(%))) of the method, the measurement sites were either marked with a marker pen (marked points) or localized anatomically (unmarked points). Measurements were made from the dorsal forearm (Arm), trapezius (Tra), levator scapulae (Lev), infraspinatus (Inf) and deltoideus (Del) muscle areas. STS in the forearm was studied during different types of short-term relative isometric loading of the muscle as well as during venous occlusion. STS values of the myofascial trigger points in the Lev muscles were evaluated bilaterally. A linear, positive relationship was found between the indenter force (N) and the dynamic compressive modulus (MPa) of elastomer stiffness (r(2) = 0.90, n = 9). Intra- and interrater CVs of marked and unmarked sites varied between 4.31% and 12.06%. STS increased linearly along the relative muscle load (r(2) = 0.96) and nonlinearly during the venous occlusion (r(2) = 0.97). Statistically significant regional variation of STS was found between the different measurement sites (p < 0.05). In conclusion, STSM can evaluate tissue stiffness quantitatively and yield reproducible data.

Adult↗

PubMed2005

Postural control in male patients with hip osteoarthritis.

Earlier studies have demonstrated that postural control is worse in patients with knee osteoarthritis (OA) than in control subjects, whereas little information is available about the postural control in patients with hip OA. The aim of this study was to investigate the standing balance in different test conditions in men with hip OA and to compare the results with those of age- and sex-matched healthy controls. Twenty-seven volunteers 47-64-year-old men with hip OA and 30 randomly selected, healthy age-matched men were tested using the sensory organisation test (SOT). The center point of force velocity (CPFV (cm/s)) was also determined during one- and two-footed standing. There was no difference between the patients and controls in the SOT test, in the strategy analysis or during one-footed standing. There were no significant differences in CPFV values between the better and worse hip side. Fatiguing exercise had no effect on two-footed CPFV with eyes open, but when the eyes were closed both two and one-footed CPFV values were significantly increased (p<0.01-0.05) in both groups. No differences were found in fatiguing exercise between control and OA subjects with eyes open or closed or in one-footed trials. In OA patient's subjective pain was related to increasing CPFV (p<0.05). In conclusion, the hip OA had no effect on static balance in men.

Humans↗

PubMed2005

Increased bone mineral content but not bone mineral density in the hip in surgically treated knee and hip osteoarthritis.

OBJECTIVE: The inverse relationship between the occurrence of osteoarthritis (OA) and osteoporosis is controversial. Some investigators have found higher bone mineral density (BMD) in the hips, lumbar spine, and other skeletal sites of patients with OA; others have not. We investigated the relationship between BMD and OA. METHODS: We compared the BMD, bone mineral content (BMC), and projected area of the femoral neck (FN) and trochanter (TR) of 99 women with a validated diagnosis of primary OA from the Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) cohort, with 2012 controls. The measurements were made twice in women aged 47-59 years in 1989-91, and then repeated in 1994-98. RESULTS: After correction for age, body mass index (BMI), menopausal status, and hormone replacement therapy use before inclusion, we found no significant difference in femoral BMD of the OA patients compared with controls at baseline and at 5-year followup (FN +2.7%, +4.6%, respectively; nonsignificant). However, the BMC was significantly higher in all regions of interest in OA patients at baseline [FN +8.3% (p = 0.004); TR +13.3% (p = 0.017)]. The projected area of FN was also significantly higher at baseline and followup in OA patients (FN +3.7%, +3.9%, respectively; p < 0.001). The projected area of the bones increased in all subjects over the followup period. The BMD decrease rate was higher in OA patients for all regions of interest during followup. CONCLUSION: Hip BMD of women treated surgically for hip or knee OA was not different from that of healthy controls when measured twice with a 5-year interval. However, at 5-year followup, OA can be accompanied by an increase in bone size or changes in shape, and faster loss of BMD.

Absorptiometry, Photon↗

PubMed2004

Effects of vocationally oriented medical rehabilitation for aircraft maintenance personnel--a preliminary study of long-term effects with 5-year follow-up.

Changes in the physical capacity, musculoskeletal symptoms, and perceived work ability of Finnish Air Force maintenance personnel were studied after vocationally oriented medical rehabilitation (VOMR). Twenty persons with chronic musculoskeletal symptoms in their back or neck took part in VOMR courses. The measurements were carried out at the beginning of the rehabilitation course and after two follow-up periods (0.5 and 5 years). The subjects worked most of the time in a bent position and often with their backs twisted and their arms above their shoulders. The severity of low-back pain and the number of days of sick leave decreased significantly (p < 0.05-0.01) during the 5-years follow-up. Also the exercise breaks at work increased (p < 0.01). After half a year of medical rehabilitation the measured range of the cervical spine and the dynamic and endurance strength of the upper and lower extremities was greater (p < 0.05-0.001) than at the beginning of the rehabilitation. There were no statistically significant differences in the use of physical therapy, experienced work strain, physical exercise or maximal oxygen consumption during the follow-up. This is a preliminary follow-up study lasting 5 years showed some significant changes in physical capacity, musculoskeletal symptoms and work ability. However, controlled studies are needed to evaluate these preliminary findings of this kind of rehabilitation model.

Adult↗

PubMed2004

Estimation of femoral head bone density using magnetic resonance imaging: comparison between men with and without hip osteoarthritis.

Bone changes are thought to be one important etiological element in the pathogenesis of hip osteoarthritis (OA). The magnetic resonance imaging (MRI)-derived T2* relaxation time has been shown to provide information about bone mineral status of the femoral neck. The aim of this study was to test the hypothesis that the MRI-derived T2* relaxation time of the proximal femur in hip OA differs from that seen in healthy subjects. Based on the American College of Rheumatology criteria regarding classification of the OA of the hip, 27 men (aged 47-64 yr) with unilateral or bilateral hip OA and 30 age-matched randomly selected healthy men were studied. Bone mineral density (BMD), bone mineral content (BMC), and bone width of the femoral neck were measured with dual-energy X-ray absorptiometry (DXA). Subsequently, T2* measurements were performed with a 1.5-T scanner (Siemens Magnetom 63SP; Erlangen, Germany). A single 10-mm-thick coronal slice was generated on the femur, with a repetition time of 60 ms and nine echo times (4-20 ms) to derive T2* values. T2* measurements were performed from the different region of interests (ROIs) from the femoral neck and head. T2* relaxation times showed significant negative correlations with BMC, BMD (r = -0.401 to -0.794; p < 0.05-0.001). T2* relaxation time values revealed no significant differences between the groups in the femoral neck and in the head of the femur, whereas it was 12% lower (p < 0.01) in OA subjects than in controls in acetabulum. There were no significant differences in the T2* relaxation time values between the radiographic OA subgroups. Our findings suggest that hip OA is not associated with an increase of BMD in the femoral neck or in the head of the femur.

Absorptiometry, Photon↗

PubMed2004

Osteoarthritis in the carpometacarpal joint of the thumb. Prevalence and associations with disability and mortality.

BACKGROUND: This study was designed to investigate the prevalence of osteoarthritis in the carpometacarpal joint of the thumb in adults thirty years of age or older in Finland. METHODS: Between 1978 and 1980, a representative population sample of 8000 Finns thirty years of age or older were invited to have a comprehensive health examination; 90% accepted. Hand radiographs were made of 3595 subjects. Since the examination, the subjects have been followed systematically to assess work disability and mortality by reviewing registers covering the whole population. RESULTS: The age-adjusted prevalence of thumb carpometacarpal osteoarthritis of Kellgren grade 2, 3, or 4 was 7% for men and 15% for women. After adjustment for age, sex, and other alleged risk factors, body mass index was found to be directly proportional to the prevalence of thumb carpometacarpal osteoarthritis in both sexes. The adjusted odds ratio was 1.29 (95% confidence interval, 1.15 to 1.43) per 5-kg/m(2) increment in body mass index. No significant association was found between the physical workload history and thumb carpometacarpal osteoarthritis. Restricted mobility of the thumb and local tenderness and swelling were frequently found in conjunction with radiographic evidence of thumb carpometacarpal osteoarthritis. Advanced (grade-3 or 4) thumb carpometacarpal osteoarthritis predicted the total mortality rate in men (adjusted relative risk, 1.32; 95% confidence interval, 1.03 to 1.69). Radiographic signs of thumb carpometacarpal osteoarthritis did not predict work disability. CONCLUSIONS: and CLINICAL RELEVANCE: Obesity is a strong determinant of thumb carpometacarpal osteoarthritis in both sexes. The effect of thumb carpometacarpal osteoarthritis on disability and mortality in the general population is modest. Because of the rarity of ensuing disability, carpometacarpal osteoarthritis of the thumb is likely to be underdiagnosed in clinical practice.

Adult↗

PubMed2002

Activation of paraspinal and abdominal muscles during manually assisted and nonassisted therapeutic exercise.

OBJECTIVE: To assess the activities of the paraspinal and abdominal muscles during manually assisted therapeutic exercises (MATEs) and nonassisted therapeutic exercises (NATEs) that are used in the initial phases of the progressive exercise programs designed for the treatment of low back pain. DESIGN: Thirteen healthy subjects volunteered in the study. Surface electromyography (EMG) was recorded. The recorded EMG signal was averaged and normalized to the maximal EMG amplitude obtained during the maximal voluntary contraction (%EMGmax). RESULTS: In general, the %EMGmax values were higher during NATEs than during MATEs. Sitting seemed to activate lumbar L5 level paraspinal muscles to the same extent as MATEs. CONCLUSION: MATEs require only minimal trunk muscle activities, and thus, they may not be sufficiently intense to improve the trunk muscle performance. NATEs require high trunk muscle activities that are adequate for improving the trunk muscle performance, but they may cause high compressive loading of the lumbar spine, and if unchecked, this can aggravate low back pain.

Adult↗

PubMed2002

Comparison of DXA and MRI methods for interpreting femoral neck bone mineral density.

The aim of the study was to improve the practical implementation of the dual X-ray absorptiometry (DXA) by converting the areal bone mineral density BMD (BMD(areal)) to volumetric BMD using magnetic resonance (MR) imaging (MRI) because a failure to control for the femoral neck size can lead to erroneous interpretation of BMD values. We also evaluated the feasibility of MR T2* relaxation time in assessing bone mineral status of the femoral neck. Twenty-eight randomly selected 47- to 64-yr-old healthy men were studied. The men had neither unilateral nor bilateral hip osteoarthritis according to radiographs. Bone width, mineral content (BMC), BMD(areal), and apparent volumetric BMD (BMD(vol)) of the right femoral neck were measured with DXA. The BMD(vol) was calculated by approximating the femoral neck to be cylindrical with a circular cross-section (Vol(dxa)). Volumetric measurements from MR (Vol(mri)) images of the femoral neck were also used to create a BMD measure that was corrected for the femoral neck volume (BMD(mri)). T2* measurements were performed with a 1.5-T scanner (Siemens Magnetom 63SP, Erlangen, Germany). A single 10-mm-thick coronal slice was generated on the femur with a repetition time of 60 ms, and nine echo times (4-20 ms) were used to derive T2* values. Vol(mri) correlated positively (r = 0.828, p < 0.001) with Vol(dxa). However, the Vol(mri) of the femoral neck was 18% lower than the Vol(dxa). Similarly, the BMD(mri) was related to the BMD(vol) (r = 0.737, p < 0.001). Because of the difference in the volumetric measures, the BMD(mri) of the femoral neck was 21% higher than the BMD(vol) (p < 0.001). T2* relaxation time showed a significant negative correlation with BMC, BMD(areal), BMD(vol), and BMD(mri) (r = -0.423 to -0.757, p < 0.05-0.001). In conclusion, these results are evidence that DXA-derived volume approximations by the cylinder with circular cross-section geometry may lead to lower DXA-derived BMD(vol) values, as compared to true MRI-derived volumetric bone mineral density. Thus, the BMD(vol) may not be an accurate method to calculate the true volumetric BMD in the femoral neck. Our results also suggest that the MRI-derived T2* method may be used to approximate the BMD in the proximal femur.

Absorptiometry, Photon↗

PubMed2002

Hip muscle strength and muscle cross sectional area in men with and without hip osteoarthritis.

OBJECTIVE: To study the hip muscle strength and cross sectional area (CSA) in men with hip osteoarthritis (OA) compared to age and sex matched healthy controls. METHODS: Based on the American College of Rheumatology criteria regarding classification of hip OA, 27 men (aged 47-64 yrs) with unilateral or bilateral hip OA and 30 age matched randomly selected healthy male controls were studied. The maximal isometric hip abductor, adductor, flexor, and extensor strength (Nm) at 0 degree of hip flexion in the supine position was determined with a dynamometer. The isokinetic hip flexion and extension strength (peak torque, Nm) was determined using angular velocities of 60 degrees /s and 120 degrees /s. The subjective severity of hip pain was rated by visual analog scale prior to the muscle strength test. CSA of the pelvic and thigh muscles was measured from magnetic resonance images. RESULTS: The reliability of intraclass correlation coefficients for repeated measures of muscle strength varied from 0.70 to 0.94 in controls and from 0.84 to 0.98 in subjects with OA. Hip isometric adductor and abductor strength was 25% and 31% lower (p < 0.001) in OA subjects than in controls, respectively. The hip isometric and isokinetic flexion strength was 18-22% lower (p < 0.01) in OA subjects than in controls, but extension strength did not differ between groups. In OA subjects, the hip flexion and extension isometric and isokinetic strength values were 13-22% lower (p < 0.05) on the more deteriorated side compared to the better side. CSA of the pelvic and thigh muscles did not differ between the groups. However, in OA subjects, the CSA of the pelvic and thigh muscles was 6-13% less (p < 0.05 to < 0.001) on the more severely affected hip compared to the better hip. CONCLUSION: Men with hip OA have significantly lower abduction, adduction, and flexion muscle strength than controls. The decrease of muscle size and hip pain may contribute to the decrease of muscle strength in hip OA. Other possible underlying causes of the muscle weakness need to be studied.

Anatomy, Cross-Sectional↗