Sami Tarnanen

Effect of isometric upper-extremity exercises on the activation of core stabilizing muscles.

OBJECTIVE To evaluate whether isometric exercises for the upper extremities could sufficiently activate core stabilizing muscles to increase muscle strength. DESIGN Cross-sectional study. SETTING Department of physical medicine and rehabilitation at a Finnish hospital. PARTICIPANTS Healthy adult women (N=20). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Peak isometric strength of the back and abdominal muscles was measured and relative loading in 5 test exercises was evaluated by surface electromyography. RESULTS The rectus abdominis and obliquus externus abdominis were activated to the greatest degree in a bilateral shoulder extension exercise and the average surface electromyographic activity was 114% and 101% compared with the amplitude elicited during the maximal isometric trunk flexion exercise. Horizontal shoulder extension elicited the greatest activation of the longissimus and multifidus muscles. In this exercise, the activity levels of the left side multifidus and longissimus muscles were 84% and 69%, respectively, compared with the level of activity elicited during trunk extension. CONCLUSIONS Of all the exercises studied, bilaterally performed isometric shoulder extension and unilaterally performed horizontal shoulder extension elicited the greatest levels of activation of the trunk musculature. Thus, it can be assumed that these exercises elicit sufficient levels of contraction of the trunk muscles for the development of their endurance and strength characteristics in rehabilitation.

Core Muscle Activation During Dynamic Upper Limb Exercises in Women

Abstract Tarnanen, SP, Siekkinen, KM, Häkkinen, AH, Mälkiä, EA, Kautiainen, HJ, and Ylinen, JJ. Core muscle activation during dynamic upper limb exercises in women. J Strength Cond Res 26(12): 3217–3224, 2012—Although several everyday functions and sporting activities demand controlled use of the abdominal and back muscles while working with the upper limbs, the activity of core muscles during dynamic upper limb exercises in the standing position has not been studied extensively. The purpose of this cross-sectional study was to examine abdominal and back muscle activity during dynamic upper limb exercises while standing and to evaluate whether dynamic exercises are appropriate for strengthening muscles. The activation of the rectus abdominis, obliquus externus abdominis, longissimus, and multifidus muscles during dynamic bilateral or unilateral shoulder exercises with or without fixation of the pelvis was measured in 20 healthy women using surface electromyography. Trunk muscle activation during isometric maximum contraction was used as a comparative reference. With bilateral shoulder extension and unilateral shoulder horizontal adduction, abdominal muscle activity was >60% of activity during reference exercises. With unilateral shoulder horizontal abduction and shoulder extension exercises, back muscle activity was >60% of the activity level reference exercise. Muscle activation levels were 35–64% lower during shoulder horizontal adduction and abduction without fixation compared with exercises with fixation. The results indicate that upper limb exercises performed in the standing position are effective for activating core muscles. Bilateral and unilateral shoulder extension and unilateral shoulder horizontal abduction and adduction with the pelvis fixed elicited the greatest activity of the core muscles.

The early changes in trunk muscle strength and disability following lumbar spine fusion

Purpose: To analyze trunk muscle function pre- and postoperatively in patients undergoing lumbar spine fusion. Associations between changes in trunk muscle strength and disability were also studied. Method: A total of 114 patients undergoing lumbar spine fusion participated in the study. The flexion and extension strength of the trunk was measured preoperatively and 3 months after surgery using a strain-gauge dynamometer. Disability and pain during the past week was evaluated with the Oswestry disability index (ODI) and visual analog scale (VAS), respectively. Results: Preoperative trunk extension and flexion strength levels were 319 N and 436 N in males, respectively, and 160 N and 214 N in females, respectively. In females 3 months postoperatively, the trunk extension strength increased by 39 N (p < 0.001) and flexion by 38N (p < 0.001), whereas it remained unchanged in males. The preoperative extension/flexion strength ratio was 0.79 in females and 0.76 in males. Three months postoperatively, the strength ratio decreased to 0.66 in males (p = 0.02). The mean ODI improved by 47% and back pain decreased by 65% (both p < 0.001). The changes in the ODI correlated with changes in trunk extension (r = −0.38) and flexion (r = −0.43) strength. Conclusions: Patients undergoing lumbar spine fusion had low trunk muscle strength and strength imbalance. Back fusion surgery leads to considerable relief of pain and disability, but patients still have low trunk extension and flexion strength levels 3 months postoperatively. Therefore, there is need for a proper progressive strength training protocols to normalize back function. Implications for Rehabilitation Disability and pain decreased considerably during early recovery after lumbar fusion surgery. The changes in trunk muscle function were small and imbalances between the function of trunk extensor and flexor muscles still existed 3 months postoperatively. Back pain during straining was only weakly associated with strength values, indicating that the reasons for the low strength values are probably related to more than just pain inhibition. The correlation between the changes in trunk muscle strength and the changes in the ODI indicate that increase of muscle strength may decrease disability of these patients.

Randomized controlled trial of postoperative exercise rehabilitation program after lumbar spine fusion: study protocol

BackgroundLumbar spine fusion (LSF) effectively decreases pain and disability in specific spinal disorders; however, the disability rate following surgery remains high. This, combined with the fact that in Western countries the number of LSF surgeries is increasing rapidly it is important to develop rehabilitation interventions that improve outcomes.Methods/designIn the present RCT-study we aim to assess the effectiveness of a combined back-specific and aerobic exercise intervention for patients after LSF surgery. One hundred patients will be randomly allocated to a 12-month exercise intervention arm or a usual care arm. The exercise intervention will start three months after surgery and consist of six individual guidance sessions with a physiotherapist and a home-based exercise program. The primary outcome measures are low back pain, lower extremity pain, disability and quality of life. Secondary outcomes are back function and kinesiophobia. Exercise adherence will also be evaluated. The outcome measurements will be assessed at baseline (3 months postoperatively), at the end of the exercise intervention period (15 months postoperatively), and after a 1-year follow-up.DiscussionThe present RCT will evaluate the effectiveness of a long-term rehabilitation program after LSF. To our knowledge this will be the first study to evaluate a combination of strength training, control of the neutral lumbar spine position and aerobic training principles in rehabilitation after LSF.Trial registrationClinicalTrials.gov Identifier NCT00834015

Neutral Spine Control Exercises in Rehabilitation After Lumbar Spine Fusion

Abstract Tarnanen, SP, Neva, MH, Häkkinen, K, Kankaanpää, M, Ylinen, J, Kraemer, WJ, Newton, RU, and Häkkinen, A. Neutral spine control exercises in rehabilitation after lumbar spine fusion. J Strength Cond Res 28(7): 2018–2025, 2014—Lumbar spine fusion (LSF) has been reported to change the biomechanics of the spine and therefore the rehabilitation after LSF is important. In this study, the effect of selected neutral spine control exercises on activation of trunk muscles after LSF was evaluated. Muscle activity was measured by surface electromyography of the rectus abdominis, external oblique, longissimus, and multifidus muscles during 6 exercises in 22 LSF patients (mean age = 59 years; age range = 25–84 years; 50% women). Muscle activity concurrent with trunk flexion and extension during maximal voluntary isometric contraction (MVIC) was used as a reference value. Pain during the effort was assessed with a visual analog scale (VAS). The highest activity in the rectus abdominis muscles was measured during bilateral shoulder extension (51% of MVIC), and in the external oblique, it occurred during unilateral shoulder horizontal adduction (48% of MVIC) and unilateral hip extension (46% of MVIC) exercises. The highest activation of the multifidus and longissimus muscles (60–104%) was measured during bilateral shoulder flexion and modified Roman chair exercises. The mean (SD) self-reported back pain VAS scores during exercises varied from 3 (7) to 16 (26). Neutral spine control exercises activate trunk muscles and cause minimal pain and are therefore feasible exercises for home-based training to improve muscle endurance and postural control after LSF. In addition, the level of muscle activity during bilateral shoulder flexion and modified Roman chair exercises was over 60% of MVIC, justifying their use in training for strength of the trunk extensor muscles.

Trunk Muscle Strength After Lumbar Spine Fusion: A 12-Month Follow-up

Objective The aim of this study was to investigate changes in trunk muscle strength 12 months after lumbar spine fusion (LSF) compared to preoperative strength. Methods A total of 194 patients (mean±standard deviation [SD] age, 61±21 years) who underwent LSF participated in this prospective longitudinal study. Physical measurements of the participants were made before surgery and 12 months postoperatively. Isometric trunk extension and flexion strength was measured using a strain-gauge dynamometer in the standing position. Strength changes were calculated. Regression analysis was performed to explore which factors predicted strength levels at 12 months postoperatively. Results The preoperative mean±SD extension strength was 205±144 N, which increased to 258±142 N (p<0.001) at the 12-month follow-up. Flexion strength increased from 295±172 N to 364±164 N (p<0.001). The preoperative extension/flexion strength ratio was 0.75±0.38 and remained similar (0.73±0.26) at 12 months postoperatively (p=0.39). Conclusion Although trunk muscle strength increased by 26% for extension and 23% for flexion at the 12-month postoperative follow-up, both values remained objectively low. In addition, flexion strength remained higher than extension strength, which indicates an imbalance between those muscle groups. Age, severe back pain, and low trunk muscle strength before surgery predicted low trunk muscle strength at 1 year after spinal fusion.

Effectiveness of postoperative home-exercise compared with usual care on kinesiophobia and physical activity in spondylolisthesis : A randomized controlled trial

OBJECTIVE To study the effectiveness of a 12-month exercise therapy on kinesiophobia and physical activity in patients with spondylolisthesis after lumbar spine fusion. DESIGN Randomized controlled trial. SUBJECTS Patients (n = 98) with spondylolisthesis who had undergone lumbar spine fusion. METHODS All patients (mean age 59 years) had received lumbar spine fusion surgery and identical postoperative instructions. Three months postoperatively, they were randomized into an exercise group (n = 48) or usual care group (n = 50). The exercise group received 12-month progressive home-based training with regular booster sessions, and the usual care group a single session of physiotherapy instruction. Kinesiophobia was assessed with the Tampa Scale for Kinesiophobia (TSK) and physical activity by the International Physical Activity Questionnaire (IPAQ) preoperatively, 3 months after lumbar spine fusion, and at the end of the 12-month intervention. RESULTS Before the intervention, the median (first quartile; third quartile) of TSK was 32.5 (29.0; 37.0) in the exercise group and 30.0 (25.8; 36.0) in the usual care group, changing to 30.0 (25; 36) in the exercise group and to 30.5 (24; 36.3) in the usual care group (between-group p = 0.17). IPAQ metabolic equivalent minutes per week increased from 1,863 (1,040; 3,042) to 3,190 (1,634; 6,485) in the exercise group and from 2,569 (1,501; 4,075) to 3,590 (1,634; 6,484) in the usual care group (between-group p = 0.92). CONCLUSION Progressive 12-month home-exercise starting 3 months postoperatively was not superior to usual care in decreasing kinesiophobia or increasing physical activity in spondylolisthesis.

Patients Undergoing Lumbar Spine Fusion has Low Trunk Muscle Strength and Imbalance between Flexor and Extensor Muscles Preoperatively and still 1 Year after the Surgery

Introduction Lumbar spine fusion (LSF) may be performed in the treatment of several spinal disorders if conservative treatment fails. Decreased physical activity due to pain together with spinal fusion may cause muscle atrophy and therefore decrease the trunk muscle strength. Previously, the average trunk muscle strength in flexion and in extension were reported to be 564 and 629 N, respectively, in control population compared with those of 375 and 404 N in patients 2 months after disc herniation surgery (Häkkinen et al, 2003). In healthy people trunk extensor strength has been reported to be greater than flexor strength, that is, extensor/flexor strength ratio is more than 1 (Yahia et al, 2011). Objective The aim of the present study was to evaluate the influence of lumbar spine fusion to the flexion and extension strength of the trunk muscles at 1 year follow-up after the surgery. Material and Methods Altogether 195 patients (66% females, mean [SD] age 61 [12] years and body weight 78 [15] kg) undergoing instrumented LSF attended the present study. Indications for surgery were degenerative spondylolisthesis, spondylolysis, spinal stenosis, disc herniation or degeneration, postoperative conditions or scoliosis. The median (IQR) duration of preoperative back pain was 31 (18, 66) months. Isometric flexion and extension strength of the trunk muscles was measured using a strain-gauge dynamometer and back pain was measured using visual analogue scale (VAS 0–100 mm) preoperatively and at 1 year after surgery. Results Mean (SD) preoperative trunk flexion and extension strength levels were 295 (172) and 205 (144) N, respectively. A year after the surgery, mean (95% CI) trunk flexion strength increased by 69 (53–85) N (p < 0.001) and extension strength by 53 (37–70) N (p < 0.001). Mean (SD) preoperative extension/flexion strength ratio was 0.75 (0.38) and did not change during the follow-up. Flexion strength/body weight ratio increased from preoperative 0.38 (0.20) by 0.09 (0.07–0.11) and extension strength/body weight ratio from 0.27 (0.18) by 0.07 (0.05–0.09) (p < 0.001) 1 year after the surgery. Mean (SD) back pain VAS decreased from preoperative 63 (27) to 25 (26) mm at 1 year and pain intensity during flexion and extension strength measurements decreased from 41 (29) to 11(21) mm and from 55 (29) to 14 (25) mm, respectively (p < 0.001). No correlation between strength measurements and back pain was found at either time point. Conclusion The trunk muscle strength in patients with chronic back pain undergoing LSF is low. After LSF some improvement can be found, however, still 1 year after the surgery the trunk muscle strength remains low. Moreover, the flexion strength is better than extension strength, which is in contrast to results of healthy people in previous studies. Therefore, after the spinal fusion surgery the rehabilitation should aim at improving muscle strength and special attention should be paid to correct the imbalance between trunk flexion and extension muscles.

Trunk Extensor Muscle Activity during Exercises in Patients after Lumbar Fusion Surgery

Introduction The goal of postoperative rehabilitation after lumbar spine fusion (LSF) is to decrease pain and disability; however, back function should also be taken into account. Low trunk muscle strength has been reported in patients after LSF and it correlates with poor disability1. To increase the trunk muscle strength after fusion surgery the training should also include more intensive exercises. Exercises that are performed lumbar spine in a neutral position allow loading without the strain of fused segment. The purpose of present study was to determine trunk extensor muscle activity during different exercises and evaluate association between pain during loading and muscle activation in patients after LSF. Materials and Methods A total of 22 patients (50%women) with mean (SD) age of 59 (17) years who had undergone LSF 3 to 11 months earlier participated in the study. The indications for surgery were spondylolysis, degenerative olisthesis, spinal stenosis, and degenerative disk disease. Bilateral surface electromyography (EMG) activity of trunk extensor muscles (longissimus at the L1 level and multifidus at L5) was measured during dynamic upper limb exercise (bilateral shoulder flexion in the standing position). The load was individually adjusted using a pull machine so that each subject was able to perform 10 repetitions per set. In addition, lower limb exercise (right hip extension in the four-point kneeling position) with 10 repetitions and static back extension exercise (in the Biering-Sorensen test position) were studied. The starting and finishing points of the fifth repetition in the upper and lower limb exercises were determined from simultaneous EMG and video analysis, and this period was used for analysis. In static trunk extension exercise, the first 3 seconds were taken to analysis. The raw EMG signal was rectified and averaged. Then, the reference EMG activities obtained from maximal isometric trunk extension strength measurement (reference value) were used to normalize the EMG-activation levels collected for trunk muscle exercises. The intensity of back and leg pain during the past week and during the exercises was assessed by visual analogue scale (VAS, 0–100). Results The mean (SD) trunk extension strength was 341 (204) N. The highest activation in the longissimus was measured during the static back extension exercise. The activity on the right side was 104% and on the left side 83% when compared with the reference values. The corresponding values during bilateral shoulder flexion were 65 and 62%. The highest activity levels of the multifidus (62% on the right side and 64% on the left side) were also measured during the static back extension exercise. Activity levels of multifidus were 55% on the right side and 52% on the left side during bilateral shoulder flexion and 34% and 27% during right hip extension exercise. EMG activities of longissimus (p < 0.005) and left multifidus (p < 0.009) were higher during the static back extension than during the bilateral shoulder flexion exercise. The activation of longissimus and multifidus muscles was higher in the upper limb than in lower limb exercise (both p < 0.003). The average intensities of back and leg pain during past week were 19 (19) mm and 15 (20) mm, respectively. In all participants during the reference and exercises measurements, back pain was less than 16 mm and leg pain was less than 9 mm. No significant correlation was found between strength and pain in back or leg during measurements. Back pain correlated only with right side multifidus activity during static back extension exercise (r = −0.45, p < 0.04). Conclusion Static back extension exercise elicited the highest longissimus and multifidus muscle activity. Bilateral shoulder flexion exercise in the standing position also elicited muscle activity that may be high enough to develop muscle endurance and strength characteristics. All studied exercises are feasible in the postoperative rehabilitation after lumbar fusion surgery because pain intensity remained at relatively low level. All studied exercises are performed in the lumbar spine in the neutral position, thus strain of fused segment is minimized. I confirm having declared any potential conflict of interest for all authors listed on this abstract Yes Disclosure of Interest None declared Tarnanen SP, et al. 2012, Submitted