Marc Vanderthommen

Hamstring muscle strain recurrence and strength performance disorders

We determined the frequency of strength disorders in 26 athletes with a history of hamstring muscle injury and recurrent strains and discomfort. We also assessed the effectiveness of rehabilitation to correct muscle performance. After concentric and eccentric isokinetic assessment, 18 athletes were found to have strength deficits, as determined by statistically selected cutoffs of peak torque, bilateral differences, and the flexors/quadriceps ratio. The discriminating character of the eccentric trial was demonstrated, combining a preferential eccentric peak torque deficit and a significant reduction of the mixed eccentric flexors/concentric quadriceps ratio. The athletes with muscle imbalances followed a rehabilitation program individually adapted from their strength profile. Treatment length was from 10 to 30 sessions and resulted in isokinetic parameter normalization in 17 of 18 subjects. Isokinetically corrected subjects were observed for 12 months after return to athletics. None sustained a clinically diagnosed hamstring muscle reinjury. Subjective intensity of pain and discomfort were significantly reduced, and they all returned to their prior level of competition. These results demonstrate that persistent muscle strength abnormalities may give rise to recurrent hamstring injuries and discomfort. An individualized rehabilitation program emphasizing eccentric training based on specific deficits contributes to a decrease in symptoms on return to sports.

Electrical stimulation as a modality to improve performance of the neuromuscular system

Transcutaneous neuromuscular electrical stimulation (NMES) can modify the order of motor unit recruitment and has a profound influence on the metabolic demand associated with producing a given muscle force. Because of these differences, interventions that combine NMES with voluntary contractions can provide beneficial outcomes for some individuals. The adaptations evoked by NMES are not confined to the activated muscle but also involve neural adaptations through reflex inputs to the spinal cord and supraspinal centers.

Spatial Distribution of Blood Flow in Electrically Stimulated Human Muscle: A Positron Emission Tomography Study

Neuromuscular electrical stimulation (NMES) was studied with positron emission tomography (PET) and H215O in the quadriceps muscle of 11 men. The subjects were submitted to simultaneous bilateral isometric contraction (5 s)–rest (5 s) cycles for 12 min, with a workload corresponding to 5% of quadriceps maximal isometric voluntary torque (QMIVT) for one thigh (5%T) and 10% of QMIVT for the other (10%T). Scans were centered at the electrodes and tissue blood flow (TBF) was evaluated in square regions of interest (ROIs) (3.5 cm2) in the transverse section (TS) of both thighs. The mean TBF reached 8.9 mL min−1 100 g−1 in the TS of the 5%T and 11.5 mL min−1 100 g−1 in the TS of the 10%T (P > 0.05). A negative linear relationship was found for both thighs between the ROI–electrode distance and the TBF (P ≤ 0.009). The mean percentage of activated ROIs (TBF > 5 mL min−1 100 g−1) was lower in the 5%T than in the 10%T (50.6% vs. 62.2%; P = 0.017). With NMES, the pattern of spatial recruitment appears linked to electrode proximity and is spatially extended. These results confirm the utility of combining NMES with voluntary exercise in the treatment of atrophied muscle.

Effectiveness of a semi-intensive multidisciplinary outpatient rehabilitation program in chronic low back pain

OBJECTIVES To evaluate the efficacy of a semi-intensive multidisciplinary outpatient program complying with the requirements of the Belgian National Institute for Health and Disability Insurance and intended for patients with chronic low back pain. METHODS We included 262 patients with nonspecific chronic low back pain, among whom 136 (73 women and 63 men) with a mean pain duration of 11.3 years completed the outpatient program (36 sessions each lasting 2h). The program consisted of education about back-sparing techniques, interventions by an occupational therapist and psychologist, and physical reconditioning. Three sessions (sessions 1, 18, and 36) were used to evaluate pain intensity, functional impairment, kinesiophobia, cognitive knowledge, knowledge of appropriate spinal movement technique, and physical performance (trunk muscle strength and endurance, mobility of the pelvis and lumbar spine, and aerobic capacity). RESULTS All study variables were significantly improved at study completion compared to baseline: pain intensity was decreased by 44%, functional impairment by 40%, and kinesiophobia by 11% whereas knowledge was improved by 59%, back-sparing technique by 95%, trunk muscle strength by 40% on average, trunk extensor muscle endurance by 90%, mobility by 8%, and aerobic capacity by 18%. CONCLUSIONS A semi-intensive multidisciplinary outpatient program was beneficial in patients with chronic low back pain. Careful patient selection and increased patient involvement in the program may help to improve adherence.

A Positron Emission Tomography Study of Voluntarily and Electrically Contracted Human Quadriceps

Keywords: muscular blood flow; positron emission tomography; nuclear magnetic resonance

Relationship between different measures of pain-related fear and physical capacity of the spine in patients with chronic low back pain

BACKGROUND CONTEXT It has been controversially stated that pain-related fear is a more important determining factor for disability in chronic low back pain (CLBP) than pain or physical impairment in itself. So far, the relationship between psychological and physiological determinants of chronic pain, that is, pain-related fear and physiological abilities, remains unclear. PURPOSE To evaluate whether pain-related fear assessed by different tools (both task specific and non task specific) is related to physical capacity measured by specific spine tests and, secondarily, to explore the relationship between different pain-related fear assessment tools. STUDY DESIGN/SETTING Cross-sectional study. PATIENT SAMPLE Fifty patients with CLBP (50% women; meanage [standard deviationage]: 44.2 [9.5 years]). OUTCOME MEASURES Physical capacity by means of three specific spine tests, that is, the finger-floor distance test (flexibility), a maximal isometric strength test of trunk extensor muscles (strength), and the Sorensen test (endurance). Pain-related fear by means of self-report measures, that is, the Tampa Scale for Kinesiophobia (TSK), the Photograph Series of Daily Activities (PHODA), and a fear visual analog scale (FVAS) tailored to the spine tests. METHODS Participants were asked to complete the TSK and PHODA and to perform the three spine tests. Right before performing each of the spine tests, an FVAS was filled out. Linear regression analyses controlling for gender and age were performed to study the association between the pain-related fear measurements and the results of the spine tests. To investigate the relationship between the pain-related fear measurements, correlation tests were performed. RESULTS The linear regression analyses revealed that neither the TSK and PHODA scores nor the FVAS scores were significantly related to the physical capacity measurements. The correlational tests showed no significant correlation between the PHODA, TSK, and FVAS scores. CONCLUSIONS The present study shows that neither the task-specific tool (FVAS) nor the non task-specific questionnaires (TSK and PHODA) were significantly correlated to the spine tests in patients with CLBP. This is contrary to earlier evidence according to which physical capacity is inversely related to the level of pain-related fear, and it suggests that one should not draw conclusions about physical capacity based on pain-related fear scores. Furthermore, the different assessment tools for pain-related fear were surprisingly not correlated with each other.

Cryotherapy in rheumatic diseases

Joint Bone Spine - In Press.Proof corrected by the author Available online since samedi 26 novembre 2011

Benefits of a Physical Training Program After Back School for Chronic Low Back Pain Patients

Objectives: Compare a treatment combining a back school program and physical training with a treatment consisting of only a back school program undertaken by chronic low back pain [CLBP] patients. Methods: Forty CLBP patients [21 females] completed an educational back school program. Once ended, 17 subjects [the Education-Physical Group [EPG]] started physical training sessions attended twice a week [90 minutes] for six weeks. The others constituted the Education Group [EG]. All subjects performed three tests: the pain visual analog scale, the Dallas questionnaire assessing quality of life, and an ergonomic test at the beginning [Day [D] 1], at the end [D21] of the back school program, and three months later [D120]. The EPG also carried out physical tests at the start and at the end of the physical training. Results: At D21, no significant difference in pain and Dallas scores appeared, although patients of both groups performed the ergonomic test significantly better. At D120, the decrease of pain intensity and the quality of life improvement were significant in both groups [P < 0.05]. The extent of the pain intensity decrease was significantly higher in the EPG compared to the EG. The EPG displayed improvements in most physical assessments [P < 0.05]. Only the increase of knee extensors strength correlated significantly with the improvements of quality of life and ergonomic function scores. Conclusions: This study supports positive effects of a back school program for CLBP patients. Additional physical training sessions lead to lower pain intensity, greater improvement of quality of life than back school sessions only, as well as improvement of muscle performances. The increase of the knee extensors strength might have helped to decrease the pain and improve the quality of life.

Le comportement gestuel du patient lombalgique fréquentant une école du dos: analyse préliminaire d'un test d'évaluation

Objective The purpose of this study was to evaluate the efficiency of a back school program on the gesture behaviour of patients with low back pain.

Cardiovascular Responses to Static Assessments of Trunk Muscles

ABSTRACT. Objectives: To investigate the cardiovascular responses to standard static assessments of strength and endurance of trunk extensor muscles. Methods: Trunk extensor performances of 10 healthy men, age 48.2 ± 5.6 years, and 10 healthy women, age 49 ± 5.7 years, were assessed by means of a maximum static strength test [consisting in maximal voluntary contractions [MVC] performed with a specific dynamometer], and two static endurance tests [the Sorensen test, and a 50 percent MVC test]. Heart rate [HR], auscultatory systolic blood pressure [SBP], and diastolic blood pressure [DBP] were recorded throughout the tests. Results: The MVCs induced significant increases of HR and SBP [mean peak values averaging 90 [female] to 95 [male] beats per minute [bpm] and 133 [female] to 141 [male] mmHg]. The HR, SBP, and DBP values increased significantly across time throughout both endurance static tests. At the end of these tests, mean HR, SBP, and DBP reached 114 to 122 bpm, 172 to 185 mmHg, and 112 to 120 mmHg, respectively. Genders differed significantly with regard to holding times [longer in females], but a gender effect was only found on SBP [higher in males]. HR and SBP increases were significantly higher in males than in female subjects. Conclusions: The strength test seems less demanding than expected, though our results need to be confirmed. Standard static endurance tests yield sizeable functional stress on the cardiovascular system. Our study emphasizes the need to exclude subjects with cardiac trouble from such efforts and suggests the relevance of monitoring cardiovascular parameters if tests are performed until exhaustion.