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PubMed2001

Vaginal palpation of pelvic floor muscle strength: inter-test reproducibility and comparison between palpation and vaginal squeeze pressure.

BACKGROUND: Vaginal palpation is commonly used in clinical practice to teach and evaluate pelvic floor muscle strength, and several grading systems have been developed. The aim of the present study was to test inter-rater reproducibility of the modified Oxford grading system and compare results from vaginal palpation with squeeze pressure measurement. METHODS: Twenty female physical therapy students, mean age 25.1 years (range 21-38) participated in the study. Two experienced physical therapists conducted the palpation test in random order. Muscle strength was classified according to a 6-point scale (modified Oxford grading system). Results from the palpation test were compared with measurement of vaginal squeeze pressure using a vaginal balloon connected to a fiberoptic microtransducer (Camtech AS, Sandvika, Norway). To ensure validity of pressure measurement only contractions with simultaneous observation of inward movement of the perineum were registered. RESULTS: The inter-rater reliability for vaginal palpation was 0.70 measured by Spearman's rho (p<0.01). Cohen's Kappa was kappa=0.37 (SEM 0.16). There was agreement between the physical therapists in nine subjects (45%). In all but one subject the disagreement was one category. Mean maximal strength for the group was 19.7 cm H2O (95% CI: 16.5-22.9). There were no differences between weak, moderate, good and strong muscle contraction classified by palpation test when comparing results from the vaginal squeeze pressure (p=0.66). CONCLUSIONS: Vaginal palpation is mandatory when teaching correct pelvic floor muscle contraction. However, the present results indicate that the method is not reproducible, sensitive and valid to measure PFM strength for scientific purposes.

Adult↗

PubMed1990

Two theories of muscle strength augmentation using percutaneous electrical stimulation.

Electrical stimulation of muscle is a commonly used, well-substantiated strategy that physical therapists use to augment strength in patients with muscle weakness. Two distinctly different theories of strength augmentation using percutaneous muscle stimulation are presented. The first theory proposes that augmentation of muscle strength with electrically elicited muscle contractions occurs in a similar manner to augmentation of muscle strength with voluntary exercise. Electrically elicited muscle contractions of relatively high intensity with low numbers of repetitions strengthen muscle proportionally to the external load on the muscle in a manner that is equivalent to voluntary contraction. The second theory proposes that augmentation of muscle strength using percutaneous stimulation is fundamentally different from augmentation of strength with voluntary exercise. This theory uses the physiological differences between electrically elicited and voluntary contractions, such as the reversal of motor unit recruitment order, as a basis for argument. Both theories are partially substantiated using published literature. Strategies for testing both theories are also presented.

Electric Stimulation Therapy↗

PubMedDate not supplied

Isometric muscle strength and quantitative electromyography of back muscles in wrestlers and tennis players.

The isometric motor performance of the trunk muscles was studied in 10 male wrestlers and 9 male tennis players, all of whom were elite athletes. Isometric flexion, extension, and lateral bending were performed. The motor output, including fatigue, was studied by means of a load cell and using electromyography. The wrestlers were found to have symmetrical strength and were stronger in all measured directions, especially in side bending (flexion, 852 N; extension, 951 N; right and left side bending, 759 N and 744 N, respectively), than the tennis players and normal subjects of any published study. The development of fatigue in the erector spinae muscles, as evaluated by spectral analysis of the myoelectric signal, was not symmetrical and was significant bilaterally at the lumbar level and on the right side at the thoracic level. As expected, the tennis players had asymmetrical isometric strength. They were stronger in left side bending than right side bending (643 N compared with 557 N, P less than 0.01), and stronger in extension than flexion (835 N compared with 638 N, P less than 0.01). The development of fatigue in the erector spinae muscles was significant bilaterally at the lumbar level and on the left side at the thoracic level. The development of fatigue in the tennis players was less than that of the wrestlers except for the left thoracic measurement site. Our conclusions are that tennis players appear to be relatively weak in trunk flexion. The wrestlers displayed a development of fatigue that was asymmetrical and was of nearly the same degree as the tennis players, but on the opposite side.

Adult↗

PubMed1996

Effects of laparoscopic cholecystectomy on global respiratory muscle strength.

Laparoscopic cholecystectomy has a better postoperative outcome than the traditional open technique, which has been shown to significantly affect respiratory muscle function. The aim of this study was to investigate the effects of laparoscopic surgery on respiratory function, and particularly that of the respiratory muscles. Respiratory muscle strength was assessed in 26 patients who underwent laparoscopic cholecystectomy and in 25 who underwent open cholecystectomy by measuring mouth pressure during maximum static inspiratory (PImax) and expiratory (PEmax) efforts. PImax, PEmax, and blood gases were measured 24 h preoperatively (-24 h) as well as 24 h (+24 h) and 48 h (+48 h) postoperatively. FEV1 and FVC were measured at -24 h and +48 hr, and the ratio of FEV1 to FVC (FEV1/FVC) was calculated. PImax decreased at +24 h and +48 h in both groups, but this decrease was significantly greater in the patients who had open surgery, (p < 0.01, and p < 0.005, respectively). Similarly, PEmax was significantly smaller in the open- than in the laparoscopic-surgery group (p < 0.0001) at +48 h. Spirometric indices showed a more severe restrictive defect at +48 h after open surgery than after laparoscopy (p = 0.01). The arterial oxygen tension (PaO2) was significantly greater in the laparoscopic- than in the open-surgery group at +24 h (p < 0.007). Laparoscopic cholecystectomy caused smaller decreases in respiratory muscle strength than did open surgery. This accords with the hypothesis of phrenic nerve inhibition during open surgery. The results are of clinical importance, since they may explain the different outcomes with the two techniques.

Adult↗

PubMed2005

Relationship between muscle strength in various isokinetic movements and kick performance among soccer players.

AIM: The present study was carried out to examine relationships between muscular strength and ball velocity with respect to 3 different approach angles and focussing on both the kicking leg and the supporting leg among soccer players of different skill levels. METHODS: Fourteen university soccer players were divided into 2 groups (superior group, average group), and kicked the ball with maximal effort towards a target 15 m away. The angles of approach to the stationary ball varied in 3 directions (free, 1.57, 2.36 rad to the kick direction). Mean ball velocity and the success rate of striking the target with the ball were measured. Maximal isokinetic and concentric muscular strength was measured in terms of motions of the knee Ext/Flex, hip Ext/Flex and hip Abd/Add using an isokinetic dynamometer. RESULTS: The mean ball velocity at free and 1.57 rad approach angles related significantly with hip Add but not with knee Ext strength for the kicking leg. In contrast, the ball velocity at an approach angle of 2.36 rad significantly correlated with knee Ext and hip Flex of the kicking leg. Although ball velocity at the free and the 1.57 rad approach angles showed no relation to strength of the supporting leg, the ball velocity at the 2.36 rad approach angle showed a significant relationship with knee Flex, hip Ext and hip Abd strength of the supporting leg. Furthermore, the superior group had more strength variables related to performance than the average group. CONCLUSIONS: Different approach angles would alter the requirement on muscle strength potential of both kicking and supporting leg during kicking. Especially an angled approach to the kick direction could require greater hip extension and abduction strength on the supporting leg for a higher capability for stabilizing body balance. Besides, skill level may alter the importance of muscle strength requirement to kick performance.

Adult↗

PubMed1981

Relationship between respiratory muscle strength and vital capacity during partial curarization in awake subjects.

To determine the relationship between respiratory muscle strength and changes in normal vital capacity (VC), graded levels of muscle weakness were produced in six healthy supine male subjects by four successive doses of d-tubocurarine (0.05 mg/kg each). The maximal effect of d-tubocurarine abolished hand-grip strength and ability to sustain head lift for 5 s, but VC was decreased to only 66 +/- 3 per cent of control. At each level of weakness decreases in VC were significantly less than were decreases in respiratory muscle strength (RMS) monitored by maximum static inspiratory and expiratory pressures. The first dose decreased RMS to 86 +/- 3 per cent of control, but VC was unchanged. Following the second dose,, VC (97 +/- 4 per cent). The VC after the third dose was still 85 +/- 3 per cent of control, while RMS had decreased to 58 +- 2 per cent. Following the final dose of d-tubocurarine (cumulative total 0.20 mg/kg), RMS was 39 +/- 2 per cent of control, compared with VC, 66 +/- 3 per cent of control. The relationship between VC and RMS was curvilinear and conformed to predictions based on the static mechanical characteristics of the normal respiratory system. These findings demonstrate that while VC is relatively spared during partial curarization, this sparing of VC does not indicate a similar extent of preserved RMS. Rather, it reflects the relative ease with which weakened respiratory muscles are able to drive the normal respiratory system in the supine subject. The same weakened muscles may be unable to generate sufficient force to handle mechanical challenges such as coughing and vomiting.

Adult↗

PubMed1994

Muscle strength and fiber adaptations to a year-long resistance training program in elderly men and women.

BACKGROUND: To study the effects of resistance training on muscle strength and size in older people, we enrolled 8 men and 17 women (mean age 68.2 +/- 1 SEM) into a one-year exercise trial. METHODS: Subjects were randomly assigned to exercise or control groups. Muscle biopsies were obtained from 11 subjects (8 exercisers/3 controls) at baseline and after 15 weeks; exercisers underwent another biopsy at 30 weeks. After testing maximum strength using the 1-RM method, the exercisers began a 12-exercise circuit (3 sets of 8 repetitions at 75% of 1-RM), 3 times a week. The controls repeated the strength testing every 15 weeks. They were asked to continue usual activities and not to start any exercise program. RESULTS: With exercise, muscle strength increased, average increases ranging from 30% (hip extensors) to 97% (hip flexors). Strength increased rapidly over 3 months, then plateaued for the duration of the experiment. No strength changes were observed in sedentary controls. Cross-sectional area of type 1 muscle fibers increased in exercisers by 15 weeks (29.4 +/- 1%, p < .02) and after 30 weeks (58.5 +/- 13.7%, p < .002) compared to baseline. Type 2 fiber area did not change at 15 weeks, but increased by 30 weeks of training (66.6 +/- 9.5%, p < .0002). CONCLUSIONS: These results suggest that prolonged moderate to high intensity resistance training may be carried out by healthy older adults with reasonable compliance, and that such training leads to sustained increases in muscle strength. These improvements are rapidly achieved and are accompanied by hypertrophy of both type 1 and type 2 muscle fibers.

Aged↗

PubMed1999

Movement velocity dependent muscle strength in Parkinson's disease.

We measured isokinetic muscle strength of knee extension and flexion in 18 patients with Parkinson's disease who showed marked laterality in symptom severity and compared strength between the sides in the same patient. In all patient groups, the maximum peak torque of the more affected side was significantly less than for the less affected side at 15 revolutions per minute (r.p.m.) and 30 r.p.m. with the difference between the sides being larger at 30 r.p.m. than at 15 r.p.m., while at 5 r.p.m. there were no significant differences between sides. In the Yahr stage I group, the maximum peak torque in both extension and flexion at each velocity showed no significant difference between the sides. In contrast, in the stage II and III groups the maximum peak torque at 5 r.p.m. showed no significant difference between the sides, while at 15 r.p.m. and 30 r.p.m. these values showed a tendency and a significant difference between the sides, respectively, with the more affected side being weaker. These results suggest that muscle weakness in patients with Parkinson's disease increases with performance velocity, especially as the disease progresses.

Acceleration↗

PubMed2003

Eccentric muscle strength in functional ankle instability.

PURPOSE: To investigate muscle strength in subjects with unilateral functional ankle instability, with the specific aim of determining whether eccentric strength deficits exist. METHODS: Isokinetic invertor and evertor torques were assessed eccentrically and concentrically at speeds of 60 and 120 degrees.s(-1) in 16 subjects with unilateral ankle instability. Absolute peak torque values were compared between the injured and noninjured limbs to determine whether strength deficits existed. RESULTS: No eccentric or concentric evertor strength deficit was found in the injured limb. Interestingly, for the injured limb, a significant interaction effect was found whereby eccentric inversion strength was reduced. CONCLUSION: Functional ankle instability is not associated with deficits in evertor strength. Deficits in eccentric invertor strength were found, and this may contribute to the symptoms of functional ankle instability. Weak invertors may contribute to functional ankle instability because of a reduced ability to assist in controlling lateral displacement of the shank over the weight-bearing foot. Excess lateral postural sway outside of the base of support results in the foot's medial border rising from the floor once the limits of closed chain eversion is reached, which may result in the foot being forced into rapid inversion.

Adolescent↗

PubMed1993

Muscle strength in osteoporotic versus normal women.

Strong back muscles contribute to good posture and skeletal support. Osteoporosis, being a metabolic bone disease, should not affect muscle strength. In this study we were interested in comparing the back extensor strength (BES) of osteoporotic and normal women. Fifty-five women ages 40-85 years who had a documented diagnosis of osteoporosis and were referred for initiation of proper exercise programs were included in our study after meeting the inclusion criteria. They all had evaluation of their posture, back and upper extremity strength, and physical activity score through our Rehabilitation of Osteoporosis Program--Exercise (ROPE). In addition, to avoid the interference of pain on application of maximal effort, we did not include subjects with acute back pain or those who experienced back pain with maximal effort during the testing trial. BES for osteoporotic women ranged from 16 to 65 lb (mean +/- SD, 36.5 +/- 15.5) for ages 40-59 years, 9 to 55 lb (mean +/- SD, 29.9 +/- 10.6) for ages 60-69 years, 6 to 52 lb (mean +/- SD, 24.3 +/- 10.2) for ages 70-79 years, and 17 to 27 lb (mean +/- SD, 21.2 +/- 4.2) for ages 80 years or older. Comparison of these data with the BES of 25 normal women, with statistical adjustment for age, demonstrated that the osteoporotic women had significantly lower BES than the normal women. A longitudinal study of a larger group of women would be of great interest for clarifying whether the weakness of back extensors precedes and, indeed, contributes to compression fractures of the spine.

Adult↗

PubMed1992

Trunk-muscle strength during concentric and eccentric contraction: a comparison between healthy subjects and patients with chronic low-back pain.

The physical evaluation and exercise program of trunk muscles in patients with chronic low-back pain (CLBP) is still controversial. Many studies have been performed in the isometric and/or concentric contraction mode. Few data, however, have been reported on trunk-muscle strength during eccentric contraction, which plays a significant role in functional activities. To evaluate whether trunk-muscle strength on eccentric contraction could be applicable to the assessment and exercise of the patients with CLBP, trunk strength was measured in 20 healthy men and 16 healthy women, as well as 15 male and 10 female patients with CLBP. Maximum voluntary concentric and eccentric strength was measured during attempted flexion and extension in a seated position. In the healthy subjects, the maximum torque of extensors was greater than that of the flexors during both concentric and eccentric contraction (p less than 0.05). In flexors and extensors, maximum torque exerted on the eccentric contraction was always greater than that on the concentric contraction (p less than 0.05). Although strength was likely to be weaker in the patients with CLBP than in the healthy subjects, there were no statistical differences between the two groups. In terms of the flexor/extensor ratio of maximum torque, there were also no statistical significances between the two groups in either contraction mode. In the flexors, correlation coefficient (r) between concentric and eccentric torque was 0.84 for the healthy subjects and 0.48 for the CLBP subjects (p less than 0.05). In the extensors, the coefficient was 0.90 for the healthy patients and 0.71 for the CLBP patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

High voltage electrical stimulation in the augmentation of muscle strength: effects of pulse frequency.

This study was designed to determine the effects of pulse frequency (20pps, 45pps, 80pps) on subjects' voltage tolerance, delayed muscle soreness, and muscle strength gained following 6 weeks of electrical stimulation. Thirty healthy men (mean age = 22 years) were randomly assigned to three groups. Subjects in group 1 (n = 10), group 2 (n = 10), and group 3 (n = 10) had their right quadriceps femoris muscles electrically stimulated with a high-voltage pulsed galvanic stimulator present at pulse frequencies of 20pps, 45pps, and 80pps, respectively. The left limb of each subject served as the control. For all the groups, the duty cycle of the stimulator was set at 10 seconds on and 50 seconds off during the stimulation. At each training session, the maximal tolerable voltage for each subject was monitored. Ten maximum contractions was allowed at each training session. Muscle soreness perception was evaluated 48 hours after stimulation using a 10-point visual analog scale. Electrical stimulation was administered three times a week for 6 weeks. For each subject, the average voltage output and muscle soreness rating were computed at the end of each week. With a cable tensiometer, the knee extension isometric force of both limbs was evaluated before training and at the end of the second, fourth, and sixth weeks of the study and 3 weeks after training. Repeated measure's analysis of variance was used to determine significant differences in the dependent variables. The results showed that the maximum voltage tolerance, muscle soreness ratings, and muscle strength gained by the three groups are not significantly (p > .05) different.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Relationship of body composition, muscle strength, and aerobic capacity to bone mineral density in older men and women.

We evaluated the relationship of body composition, maximal aerobic capacity (VO2max), and muscle strength to bone mineral density in 91 healthy men and women, age 61-84 years. Lean body mass was estimated from two independent measures of fat mass, bioelectrical impedance and skinfold thickness. VO2max was determined by treadmill ergometry with direct measurement of oxygen consumption. Grip and back strength were measured by isometric dynamometry. Mineral density of lumbar spine and midradius were measured by dual- and single-photon absorptiometry. Men had significantly greater lean mass, muscle strength, aerobic capacity, and bone density than women. In women, grip strength correlated with forearm and spine density (r = 0.37, r = 0.28, p less than 0.05). In men, grip strength correlated with forearm density (r = 0.47, p less than 0.05), and back strength was significantly correlated with both spine (r = 0.46, p less than 0.01) and forearm density (r = 0.46, p less than 0.01). In women, neither forearm nor spine density correlated significantly with aerobic capacity. In men, midradius density did not correlate significantly with oxygen consumption, but the simple correlation between spine density and VO2max was significant (r = 0.41, p less than 0.05). Back strength and VO2max were significantly related in men (r = 0.47, p less than 0.01). By stepwise multiple regression, back strength emerged as the most robust predictor of spine mineral, accounting for 19% of the variation in bone density. Addition of VO2max to the regression did not add significant predictive value. However, when VO2max was expressed per kilogram lean body mass, both back strength and VO2max contributed significantly to the prediction of spine density in men, and the coefficient of determination R2 increased to 0.30. We conclude that body mass and grip strength, but not aerobic capacity, significantly predict bone density in elderly women. In elderly men, back strength is a more robust predictor of axial bone density than traditional expressions of aerobic capacity, but VO2max per kilogram lean mass and back strength both make significant contributions to the prediction of spine mineral density. The applicability of these results to younger men and women is uncertain.

Aged↗

PubMed2005

[Effect of inspiratory muscle training on muscle strength and quality of life in patients with chronic airflow limitation: a randomized controlled trial].

OBJECTIVE: Chronic airflow limitation (CAL) is a significant cause of illness and death. Inspiratory muscle training has been described as a technique for managing CAL. The aim of the present study was to evaluate the effectiveness of inspiratory muscle training on improving physiological and functional variables. PATIENTS AND METHODS: Randomized controlled trial in which 35 patients with CAL were assigned to receive either an experimental (n=17) or control (n=18) intervention. The experimental intervention consisted of 2 months of inspiratory muscle training using a device that administered a resistive load of 40% of maximal static inspiratory mouth pressure (PImax). Inspiratory muscle strength, exercise tolerance, respiratory function, and quality of life were assessed. RESULTS: Significant improvement in inspiratory muscle strength was observed in the experimental training group (P=.02). All patients improved over time in both groups (P<.001). PImax increased by 8.9 cm H2O per month of training. Likewise, the health-related quality of life scores improved by 0.56 points. CONCLUSION: Use of a threshold loading device is effective for strengthening inspiratory muscles as measured by PImax after the first month of training in patients with CAL. The long-term effectiveness of such training and its impact on quality of life should be studied in a larger number of patients.

Breathing Exercises↗

PubMed2006

Force steadiness, muscle activity, and maximal muscle strength in subjects with subacromial impingement syndrome.

We investigated the effects of the subacromial impingement syndrome (SIS) on shoulder sensory-motor control and maximal shoulder muscle strength. It was hypothesized that both would be impaired due to chronic shoulder pain associated with the syndrome. Nine subjects with unilateral SIS who remained physically active in spite of shoulder pain and nine healthy matched controls were examined to determine isometric and isokinetic submaximal shoulder-abduction force steadiness at target forces corresponding to 20%, 27.5%, and 35% of the maximal shoulder abductor torque, and maximal shoulder muscle strength (MVC). Electromyographic (EMG) activity was assessed using surface and intramuscular recordings from eight shoulder muscles. Force steadiness was impaired in SIS subjects during concentric contractions at the highest target force level only, with muscle activity largely unaffected. No between-group differences in shoulder MVC were observed. The present data suggest that shoulder sensory-motor control is only mildly impaired in subjects with SIS who are able to continue with upper body physical activity in spite of shoulder pain. Thus, physical activity should be continued by patients with SIS, if possible, to avoid the loss in neural and muscle functions associated with inactivity.

Adult↗

PubMed1995

Bone mass, muscle strength, and different body constitutional parameters in adolescent boys with a low or moderate exercise level.

This study was conducted to evaluate the association between muscle strength of the thigh, different body constitutional parameters, and bone mineral density (BMD) in adolescents. The subjects were 26 healthy adolescent boys, age 15.9 +/- 0.3 years, not training for more than 3 h per week. BMD was measured in total body, head, humerus, spine, femur, and tibia/fibula. Univariate correlations were measured between the explanatory parameters height, weight, body mass index (BMI), fat mass, lean body mass, quadriceps strength, hamstrings strength, and each BMD site using Pearson's coefficient of correlation. The explanatory variables were also used in a multivariate analysis to explain each BMD site. There was a high degree of concordance when comparing the two methods of analysis. Using the multivariate analysis, quadriceps strength and lean body mass showed significant independent correlations to all BMD sites measured, the correlations being stronger for the adjacent femur and tibia/fibula than for the distant humerus and head. Hamstrings strength correlated significantly and independently with tibia/fibula BMD and spine BMD. Fat mass, BMI, and weight correlated significantly and independently to all BMD sites except femur. This study demonstrates a general relationship between BMD and different body constitutional parameters and muscle strength of the thigh.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

PubMed2001

Does glucose tolerance affect elderly persons' balance, gait or muscle strength?

The aim of this study was to find out if there are associations between the deterioration of glucose tolerance and balance, gait or muscle strength among non-institutionalised northern Finnish subjects aged 70 years or over. 79% of the eligible 483 subjects participated in the study (n = 379; of whom 141 were men). 14 % (n = 19) of the men had previously diagnosed diabetes, 9% had undiagnosed diabetes, and 32% had impaired glucose tolerance (IGT). The corresponding figures for the women were 19% (n = 46), 9% (n = 21) and 35% (n = 84). The proportion of the female subjects with good balance tended to decrease along with the deterioration of the glucose tolerance status and there was a trend that disturbances in gait (walking speed, step length among the women) increased along with the deterioration of glucose tolerance. A greater proportion of the previously diagnosed diabetic subjects had decreased thenar (p = 0.09), interosseus (p = 0.00), tibialis anterior (p = 0.003), tibialis posterior (p = 0.07) and peroneus (p = 0.03) muscle strength and decreased or missing biceps (p = 0.019) and quadriceps (p = 0.010) tendon reflexes. More of the subjects with abnormal glucose tolerance had weakening of the abdominal muscles compared to the persons with normal glucose tolerance (NGT) (p = 0.001). A greater proportion of the previously diagnosed diabetic subjects had abnormal vibration sense in the sternum compared to the subjects with NGT (p = 0.028) and the tendency was similar for undiagnosed diabetes. As a majority of the abnormal findings in this study were made among the previously diagnosed diabetic patients, the long duration of hyperglycemia probably contributes to the development of these disturbances. Therefore, early detection and active treatment of hyperglycemia might prevent or at least delay the development of signs of diabetic neuropathy among elderly subjects.

Adult↗

PubMed2005

Isokinetic muscle strength of the trunk and bilateral knees in young subjects with lumbar disc herniation.

STUDY DESIGN: Cross-sectional study comparing normal subjects and patients with lumbar disc herniation. OBJECTIVE: To evaluate trunk and knee muscle strength in patients with L4-L5 and/or L5-S1 disc herniation. SUMMARY OF BACKGROUND DATA: Numerous studies have shown that patients with low back pain have weaker trunk muscles. The strength of trunk and knee muscles has not been investigated simultaneously in patients with lumbar disc herniation. METHODS: Forty-one controls and 2 patients were included. Isokinetic strength of the trunk and bilateral knees was tested on a calibrated isokinetic testing machine (Biodex System 3 Pro) regardless of the laterality of the radiculopathy. The testing was carrying out at two different velocities: 60 degrees and 120 degrees per second. RESULTS: Total trunk strength and knee strength were significantly lower in these patients (4.34 +/- 1.06 and 4.06 +/- 1.16 vs. 6.21 +/- 1.05 and 5.83 +/- 1.09 Nm/kg at 60 degrees and 120 degrees per second, respectively, P < 0.001). In patients with unilateral sciatica, there was no significant difference (P > 0.05) in unilateral knee strength between sciatica-involved and -uninvolved limbs (1.89 +/- 0.5, 1.08 +/- 0.45, 1.48 +/- 0.58, 0.93 +/- 0.41 vs. 1.68 +/- 0.45, 0.91 +/- 0.38, 1.41 +/- 0.48, 0.79 +/- 0.39 Nm/kg in sciatica-uninvolved vs. sciatica-involved limbs during extension and flexion at 60 degrees and 120 degrees per second, respectively). Total trunk strength was significantly correlated with total knee strength in both groups. CONCLUSIONS: In the patients with lumbar disc herniation, muscle strength of the trunk and knees was decreased to a similar extent. Weaker knee strength was found on either side of the lower extremity in the patients with unilateral sciatica, regardless of its location.

Adult↗