Isokinetic Trunk Extensor Research Articles

Assessment of isokinetic trunk muscle strength and its association with health-related quality of life in patients with degenerative spinal deformity

BackgroundA considerable portion of the elderly population are increasingly afflicted by degenerative spinal deformity (DSD), which seriously affects patient health-related quality of life (HRQoL). HRQoL index is used across many studies to show correlations between radio-graphical alignment, disability, and pain in patients with DSD. However, imaged structural deformity represents only one aspect for consideration, namely, the disability effect of DSD. We assessed the isokinetic strength of trunk muscle in patients with degenerative spinal deformity (DSD), and investigated its relationship with HRQoL.MethodsIn total, 38 patients with DSD (DSD group) and 32 healthy individuals (control group) were recruited. Both groups were homogeneous for age, weight, height and body mass index (BMI). Assessments were performed using the isokinetic dynamometer IsoMed-2000; trunk extensor, flexor strength and flexion/extension (F/E) ratios were explored concentrically at speeds of 30°, 60° and 120° per second. The grip strength of both hands was measured using a hand-held dynamometer. Visual analogue scale (VAS) scores, the Oswestry Disability Index (ODI), a Roland-Morris disability questionnaire (RDQ), and a 36-item Short Form Health Survey (SF-36) evaluated patient HRQoL. Correlations between trunk strength and HRQoL were analyzed.ResultsWhen compared with the control group, the DSD group showed lower trunk extensor strength at three velocity movements, and higher F/E ratios at 60° and 120°/s (p < 0.05). Both groups exhibited similar trunk flexor strength and grip strength (p > 0.05). In DSD group, trunk extensor strength at 60°/s was negatively associated with ODI and RDQ (p < 0.05). A negative relationship between trunk flexor strength at 120°/s and ODI was also recorded (p < 0.05). In addition, trunk extensor strength at 60°/s and trunk flexor strength at 120°/s were positively correlated with physical functioning and role-physical scores according to the SF-36 (p < 0.05).ConclusionsWe identified isolated trunk extensor myopathy in DSD, which causes an imbalance in trunk muscle strength. Isokinetic trunk extensor strength at 60°/s and trunk flexor strength at 120°/s can predict disability, and decrease physical HRQoL in DSD patients.

Isokinetic evaluation of the trunk muscle strength in housewives with fibromyalgia: a cross-sectional study

BackgroundIt is known that physical activity and muscular performance are reduced in fibromyalgia (FM) syndrome. This study aims to compare the performance of trunk muscles in women with FM and healthy controls and evaluate the correlation between trunk muscle strength and FM severity.MethodsForty-six patients with FM and 42 age- and body mass index-matched healthy housewives without FM were included in the FM and control groups, respectively. The Fibromyalgia Impact Questionnaire (FIQ) was used for the assessment of FM severity. The pain intensity was evaluated using the visual analogical scale (VAS). An isokinetic dynamometer was used to measure the isokinetic trunk muscle strength. The peak torque (PT) values were recorded. The psychological status of the patients was evaluated using the Beck Depression Inventory.ResultsThere was no statistically significant difference in terms of age, BMI, and BDI scores in two groups (p > 0.05, for all). The isokinetic trunk extensor PT values were significantly lower in the FM group (p = 0.002 for 60°/s, and p < 0.001 for 90°/s and 120°/s) than control group. There was a statistically significant negative correlation between FIQ score and isokinetic extensor muscle parameters.ConclusionThe results indicate that trunk extensor muscles were significantly weaker in FM patients. Trunk extensor muscle strength decreased as FM severity increased in FM patients.

Trunk muscles strength as a risk factor for nonspecific low back pain: a pilot study.

ObjectiveTo investigate the effects of asymptomatic back muscle weakness and spinal deformity on low back pain (LBP).MethodsSixty healthy subjects without LBP participated in this study. Radiography and an isokinetic/isometric dynamometer were used to respectively measure spinal scoliosis/lordosis and the strength of the trunk flexors/extensors. After 2 years, 48 subjects visited the hospital again and LBP episodes, its severity and the Korean version of the Oswestry Disability Index were assessed. Differences between the group with LBP and the group without LBP were evaluated and the association with LBP incidence and severity was determined.ResultsSex, age, and trunk strength were significantly different in both group. Sex and age were significantly positive associated with LBP incidence. The isometric trunk flexor and extensor strength, maximum isokinetic trunk flexor and extensor strength were significantly and negatively associated with the LBP severity. The maximum isokinetic trunk extensor and maximum isometric trunk extensor strength was significantly negative associated with the LBP incidence.ConclusionLBP incidence is associated with isometric and isokinetic trunk extensor weakness, whereas LBP severity is associated with age, sex, isokinetic trunk extensor and flexor weakness, isometric trunk extensor and flexor weakness.

The effect of inversion traction on pain sensation, lumbar flexibility and trunk muscles strength in patients with chronic low back pain

BACKGROUND: Effectiveness of inversion traction has been revealed in patients with chronic low back pain (CLBP), however, it is still unknown as to which angles of inversion traction positively affect patients with CLBP. OBJECTIVE: To investigate the angle-effects of inversion traction on pain sensation, lumbar flexibility, and trunk muscles (flexors and extensors) strength in patients with CLBP after an 8 week treatment program. METHODS: Forty-seven women suffering nonspecific CLBP for 23.00 ± 5.45 weeks were included prospectively and randomized into 3 groups: supine group (SG; n = 15), inversion �30 ◦ group (I30G; n = 18), and inversion �60 ◦ group (I60G; n = 14), respectively. Each group completed a 3-minute × 3-set inversion traction protocol at 0 ◦ ,i nverted�30 ◦ ,o r inverted�60 ◦ , respectively for 4 days a week during 8 weeks. The outcome measures included rating of pain using the visual analogue scale (VAS), flexibility of lumbosacral joint, and the isokinetic strength of the trunk flexors and extensors at 60 ◦ /s. RESULTS: Pain was significantly improved after 8 weeks. The reductions observed in VAS scores were lower in the I60G compared with the changes in I30G and SG. Significant interaction effects were observed in trunk flexion and extension particularly in the I60G condition. There was also a significant increase in the extensor peak torque of the I60G. CONCLUSIONS: Inversion traction at angle of �60 ◦ reduced back pain or discomfort and improved lumbar flexibility and isokinetic trunk extensor strength in patients with CLBP following an 8 week program. Therefore, this treatment modality may be suitable for patient groups of similar CLBP phenomenology.

Association Between Trunk Muscle Strength and Low Back Pain in Collegiate Wrestlers Without Lumbar Disc Degeneration

ABSTRACTLow back pain (LBP) and radiological abnormalities of the lumbar region including lumbar disc degeneration (LDD) frequently occur in wrestlers. Many research studies have described the relationship between trunk muscles and LBP. LDD is associated with trunk muscle strength and the disability level of chronic LBP. The participants enrolled in the present study included 51 Japanese collegiate wrestlers. Isokinetic trunk extensor and flexor strength was measured. The disability level of LBP was evaluated by a questionnaire on activities of daily living. Each disc from L1/2 to L5/S1 was assessed by MRI using a comprehensive LDD grading system. Irrespective of the grade of LDD, all participants were divided into two groups: 20 wrestlers (39%) were assigned to the LDD group and 31 (61%) were assigned to the non-LDD group. Negative correlation coefficients and significant differences between trunk extensor strength and the disability level of LBP were observed only in the non-LDD group. Thus, the disabil...

Trunk Muscle Strength And Muscle Cross-sectional Areas In Collegiate Wrestlers And Judo Players

The importance of trunk muscles in sports has been pointed out and their characteristics should differ depending on types of athletics. Although wrestling and judo have some similar aspects such as contact sports, the weight-classes system, movement etc., specific characteristics should be emerged. PURPOSE This study evaluated isokinetic trunk extensor and flexor strength, the cross-sectional areas of trunk muscles and physical characteristics, and compared there between collegiate wrestlers and judo players. METHODS The subjects were 30 male collegiate wrestlers and 14 judo players. Physical characteristics and isokinetic trunk extensor and flexor muscle strength using a Biodex System 3 (60, 90, 120deg/sec) were measured. The peak torques of trunk extensor and flexor muscle strength by dividing with each subject's body weight in the best trial, and the extensor/flexor ratio were used to evaluate their trunk muscle strength parameters. Magnetic resonance imaging (MRI) was also used to assess the trunk muscle cross-sectional areas obtained through the center of the L3/4 lumbar disc. We assigned five areas to the cross-section of the trunk muscles because the borderlines were unclear (rectus abdominis, internal and external obliques, psoas major, quadratus lumborum, erector spinae and multi.dus muscles). Statistical significance was positive at the 5% level using the unpaired t-test. RESULTS The sport history of judo players was significantly longer than that of wrestlers (P<0.001). The trunk flexor strength of wrestlers was significantly higher than that of judo players at 120 deg/sec (P<0.01). The cross-sectional areas of trunk muscles per bodyweight also demonstrated a significant difference between wrestlers and judo players (Rectus Abdominis; wrestling >judo, P<0.05, Obliques; wrestling <judo, P<0.05, Quadratus Lumborum; wrestling <judo, P<0.01). The larger trunk muscle areas in wrestlers probably relate to trunk flexion and/or extension movements. On the other hand, the larger trunk muscle areas in judo players may seem to contribute to trunk rotational movements. CONCLUSIONS This study indicates that different characteristics of trunk muscles exist even in the two similar sports. Such information should be useful for specific conditionings in each sport.

Comparison of Trunk Muscle Strength in Collegiate Wrestlers with Lumbar Intervertebral Disc Degeneration

1402 We reported at the 50th ACSM annual meeting that collegiate wrestlers without radiological abnormalities (RA) showed a significant relationship between trunk extensor strength and the level of low back pain. The same tendency could not be observed in wrestlers with RA. However, the RA group showed a variety of abnormalities. PURPOSE: For further characterization of the RA group, we particularly focused on the lumbar intervertebral disc degeneration (DD). We examined whether wrestlers with DD have lower trunk extensor strength than those without DD. Also, we confirmed the relationship between trunk extensor strength and the disability level of low back pain in wrestlers with DD. METHODS: The subjects were 41 male collegiate wrestlers. To focus on DD, we excluded the wrestlers who had RA other than DD. Based on the MR imaging, the three intervertebral lumbar discs from L3 to S1 were assessed. We classified the 41 wrestlers into two groups: the DD and the non-DD groups. Isokinetic trunk extensor strength was measured at three angular velocities (60, 90, 120°/sec). The indicators of trunk extensor strength were determined as peak torque, average torque, average power and work. All the trunk extensor strength parameters were divided by the subject's body weight. The functional disability level of low back pain was estimated by using a questionnaire developed by Osaka City University (the OCU test). Scores on the OCU test increased as the level of pain increased. Analyses were conducted using the unpaired t-test and Spearman's rank test. Statistical significance was positive at the 5% level. RESULTS: Without considering the level of low back pain, there were 12 wrestlers with low back pain (48%) in the DD group (N = 25) and 4 (25%) in the non-DD group (N = 16). The DD group showed a statistically significant low trunk extensor strength in most of the parameters compared with the non-DD group (peak torque at 90°/sec; P<0.01, 120°/sec; P<0.01, average torque at 90°/sec; P<0.01, 120°/sec; P<0.01, work at 60°/sec; P<0.05, 90°/sec; P<0.05, 120°/sec; P<0.01 and average power at 120°/sec; P<0.05). Body weight in the DD group was significantly heavy (P<0.05). On the contrary, trunk extensor strength did not significantly correlate with the disability level of low back pain in the DD group. CONCLUSION: We concluded that collegiate wrestlers with lumbar intervertebral disc degeneration show greater incidence of both low back pain and low trunk extensor strength. One of the reasons for the absence of significant correlation between disability level and extensor strength might be the overall low trunk muscle strength in the DD group.

Comparison of Trunk Muscle Strength in Collegiate Wrestlers with Lumbar Intervertebral Disc Degeneration

1402 We reported at the 50th ACSM annual meeting that collegiate wrestlers without radiological abnormalities (RA) showed a significant relationship between trunk extensor strength and the level of low back pain. The same tendency could not be observed in wrestlers with RA. However, the RA group showed a variety of abnormalities. PURPOSE: For further characterization of the RA group, we particularly focused on the lumbar intervertebral disc degeneration (DD). We examined whether wrestlers with DD have lower trunk extensor strength than those without DD. Also, we confirmed the relationship between trunk extensor strength and the disability level of low back pain in wrestlers with DD. METHODS: The subjects were 41 male collegiate wrestlers. To focus on DD, we excluded the wrestlers who had RA other than DD. Based on the MR imaging, the three intervertebral lumbar discs from L3 to S1 were assessed. We classified the 41 wrestlers into two groups: the DD and the non-DD groups. Isokinetic trunk extensor strength was measured at three angular velocities (60, 90, 120°/sec). The indicators of trunk extensor strength were determined as peak torque, average torque, average power and work. All the trunk extensor strength parameters were divided by the subject's body weight. The functional disability level of low back pain was estimated by using a questionnaire developed by Osaka City University (the OCU test). Scores on the OCU test increased as the level of pain increased. Analyses were conducted using the unpaired t-test and Spearman's rank test. Statistical significance was positive at the 5% level. RESULTS: Without considering the level of low back pain, there were 12 wrestlers with low back pain (48%) in the DD group (N = 25) and 4 (25%) in the non-DD group (N = 16). The DD group showed a statistically significant low trunk extensor strength in most of the parameters compared with the non-DD group (peak torque at 90°/sec; P<0.01, 120°/sec; P<0.01, average torque at 90°/sec; P<0.01, 120°/sec; P<0.01, work at 60°/sec; P<0.05, 90°/sec; P<0.05, 120°/sec; P<0.01 and average power at 120°/sec; P<0.05). Body weight in the DD group was significantly heavy (P<0.05). On the contrary, trunk extensor strength did not significantly correlate with the disability level of low back pain in the DD group. CONCLUSION: We concluded that collegiate wrestlers with lumbar intervertebral disc degeneration show greater incidence of both low back pain and low trunk extensor strength. One of the reasons for the absence of significant correlation between disability level and extensor strength might be the overall low trunk muscle strength in the DD group.

Reliability of the Isokinetic Trunk Extensor Test, Biering-Sørensen Test, and Åstrand Bicycle Test

A reliability study was performed. To determine the intersession reproducibility of the isokinetic trunk extensor strength test, the Biering-Sørensen test, and the Astrand test by calculation of the intraclass correlation coefficient and the critical difference. Several physical measurements have been used in clinical evaluation of patients with chronic low back pain. Reliability can be evaluated by calculation of either intraclass correlation coefficient or critical difference, but interpretation of the results may vary depending on which method is used. For this study, 31 patients with chronic low back pain carried out the isokinetic trunk extensor test, the Biering-Sørensen test, and the Astrand test as also did age- and gender-matched healthy individuals. Measurements were performed in three separate sessions at the same time of the day and by the same experienced examiner. The intervals between the sessions were 5 to 10 days. The isokinetic tests showed a learning effect between Tests 1 and 2. For the isokinetic test, the critical difference increased with increased angular velocities from 28% to 63% in the patients and from 27% to 39% in the healthy subjects. The critical differences for the patients and the healthy individuals were 57% vs 54% for the Biering-Sørensen test and 21% vs 23% for the Astrand test, respectively. The intraclass correlation coefficient ranged from 93% to 98% in the patients and 80%-98% in the healthy individuals. The reliability was found to be acceptable for the Astrand test and the isokinetic test at 60 degrees per second, as evaluated by the critical difference. All the tests were highly reliable according to the intraclass correlation coefficient, except for Biering-Sørensen test for healthy individuals. The critical difference is the preferable measure because calculation of the intraclass correlation coefficient may give a misleading high estimate of reliability.

Trunk extensor and flexor strength measured by the Cybex 6000 dynamometer. Assessment of short-term and long-term reproducibility of several strength variables.

Isokinetic trunk extensor and flexor strength (peak torque, total work, power acceleration time, and torque acceleration energy) at 30 degrees/sec, 120 degrees/sec, and 180 degrees/sec and isometric extensor and flexor peak torque were measured in 24 healthy women. Measurements were performed in three separate sessions at the same time of day and by the same experienced examiner. The number of days between Session 1 and Session 2 and between Session 1 and Session 3 ranged from 1 to 7 (median, 2 days) and from 23 to 48 (median, 32 days), respectively. The test results were not revealed before all sessions were completed. To determine the intrasession, short-term, and long-term reproducibility of several trunk strength variables measured by the Cybex 6000 isokinetic dynamometer (Lumex, Inc., Ronkonkoma, NY). Only few and insufficient data regarding the reproducibility of trunk strength measurements exist. Previous studies have focused on coefficients of correlation to express reproducibility. Correlations, however, are misleading and inappropriate for this purpose. The critical difference is the difference between two results that would be statistically significant when applied to a reference group in steady state. The critical difference in percentage is calculated as 2.77 X coefficient of variation (%). Isokinetic dynamometry (Cybex 6000). Reproducibility was expressed as pooled coefficients of variation, individual coefficients of variation, and critical differences. Substantial between-subject variation of coefficients of variation was found for all strength variables; for example, the 80% central range for individual coefficients of variation for long-term reproducibility of extensor strength measurements at 30 degrees/sec ranged from 2.5% to 19.5%. Critical differences calculated using the pooled variances for long-term reproducibility were higher than 20% for all measures, mounting to 80% for acceleration time. Strength testing is of limited value in the individual subject because of considerable day-to-day variability. This finding has important clinical implications.