Accepted Manuscript Neuromuscular Ultrasound Imaging in Low Back Pain Patients with Radiculopathy Lydia R. Frost, MSc, Stephen H.M. Brown, PhD PII:

S1356-689X(15)00111-3

DOI:

10.1016/j.math.2015.05.003

Reference:

YMATH 1726

To appear in:

Manual Therapy

Received Date: 21 November 2014 Revised Date:

30 April 2015

Accepted Date: 12 May 2015

Please cite this article as: Frost LR, Brown SHM, Neuromuscular Ultrasound Imaging in Low Back Pain Patients with Radiculopathy, Manual Therapy (2015), doi: 10.1016/j.math.2015.05.003. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT

Neuromuscular Ultrasound Imaging in Low Back Pain Patients with Radiculopathy

Lydia R. Frosta, MSc, Stephen H.M. Browna, PhD Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario,

RI PT

a

Corresponding author: Stephen H.M. Brown

M AN U

SC

Canada

Department of Human Health and Nutritional Sciences, University of Guelph 50 Stone Rd East, Guelph, Ontario, N1G2W1, Canada

Fax: 1 519 763 5902

TE D

Phone: 1 519 824 4120 ext 53651

AC C

EP

Email: [email protected]

ACCEPTED MANUSCRIPT

ABSTRACT Background: Patients suffering from chronic low back pain with associated radiculopathy (LBPR), or sciatica, experience neuromuscular symptoms in the lower back and leg; however,

RI PT

research to date has focussed solely on the lower back.

Objectives: To expand neuromuscular research of LBP-R patients into the lower limb, using ultrasound imaging.

SC

Design: Case control study comparing LBP-R patients to matched healthy controls.

Methods: LBP-R patients with disc bulge or herniation (L3/L4 to L5/S1) resulting in unilateral

M AN U

radiculopathy (n = 17) and healthy matched controls (n = 17) were recruited. High-resolution ultrasound imaging was used to investigate sciatic nerve structure, as well as the quality (relative magnitude of fat / fibrosis infiltration) and contraction (muscle thickening) of associated musculature in the lower back (paraspinals) and lower limb (biceps femoris, gastrocnemius,

TE D

soleus).

Results: LBP-R patients had swollen sciatic nerves (increased cross sectional area), but this was not associated with evidence of reduced lower limb muscle quality. As compared to controls,

EP

LBP-R patients demonstrated less soleus muscle thickening during submaximal contraction; however, there were no impairments in the hamstring or lower back musculature.

AC C

Conclusions: Ultrasound imaging was an effective method to detect sciatic nerve swelling in mild to moderately affected LBP-R patients. Nerve swelling was not associated with poorer muscle quality, nor consistently impaired muscle contraction.

ACCEPTED MANUSCRIPT

INTRODUCTION Chronic low back pain (LBP) is a debilitating musculoskeletal disorder that affects nearly 80% of people at some point in their lifetime (Cassidy, 1998; Andersson,

RI PT

1999). Non-specific LBP is a heterogeneous condition with multiple causes and

symptoms; as such, general LBP research limits the potential for clinical application to specific patient populations. There is therefore a need to focus studies on more

SC

homogenous groups of LBP patients. One of the most common conditions associated with LBP is lumbar radiculopathy, or sciatica, with lifetime prevalence ranging from

M AN U

1.2% to 43% (Konstantinou and Dunn, 2008). Lumbar radiculopathy is often the result of a lumbar intervertebral disc bulge or herniation compressing spinal nerve roots, and resulting neuromuscular changes. Patients with LBP and associated radiculopathy (LBPR) suffer from pain in the lower back as well as pain, tingling and/or numbness down the

TE D

legs and into the feet.

To investigate neuromuscular structure in LBP-R patients, high-resolution ultrasound provides a low-cost, dynamic and reliable alternative to MRI or computed

EP

tomography (CT). Nerve and muscle ultrasound imaging accurately reflects anatomical measurements; ultrasound measures have been shown to be comparable to dissected

AC C

measurements on cadavers for both nerve (Cartwright et al, 2013) and muscle (biceps brachii, tibialis anterior (Cartwright et al, 2013); semitendinosus, biceps femoris (Kellis et al, 2009)). Previous ultrasound-based research in LBP-R patients has found an increase in sciatic nerve cross sectional area (CSA), attributed to nerve swelling in response to chronic compression (Kara et al, 2012), impaired lower back muscle thickening upon voluntary contraction (Wallwork et al, 2009) and poorer lower back muscle quality,

1

ACCEPTED MANUSCRIPT

indicated by more fat infiltration in LBP patients as compared to controls (Chan et al, 2012). Together, research on neuromuscular structure and function has demonstrated distinct

RI PT

impairments in the lower back region of LBP-R patients. However, the symptoms and

pathology of LBP-R extend beyond the lower back to follow the anatomical course of the sciatic nerve into the lower limb. Integrity of the sciatic nerve is essential to adequately

SC

and efficiently activate the lower limb musculature. The purpose of this research was

therefore to investigate nerve and muscle structure in the lower back and lower limb in a

M AN U

chronic LBP-R population. It was hypothesized that LBP-R patients would demonstrate alterations in sciatic nerve and associated lower back and lower limb muscle structure, as compared to healthy controls. Specifically, evidence of increased sciatic nerve size, muscle fat infiltration, and decreased muscle thickening upon contraction on the

TE D

radiculopathy-affected side of LBP-R patients would be present.

MATERIALS AND METHODS

EP

Participants

Individuals with LBP-R (n = 17) and matched control participants (n = 17) were

AC C

recruited (Table 1). LBP-R patients were recruited from local chiropractic and physiotherapy clinics, and matched control participants were recruited from the general community. All LBP-R participants had unilateral radiculopathy for a minimum of 3 consecutive months as a result of a diagnosed lumbar intervertebral disc bulge or herniation between vertebral levels L3-L4 to L5-S1. LBP-R patients experienced lower back pain and at least one symptom of pain, tingling, or numbness radiating down the leg

2

ACCEPTED MANUSCRIPT

and/or foot. Control participants with no history of chronic LBP, musculoskeletal disorder, or neurological deficit were matched to LBP-R patients for age, sex, mass, height, foot dominance, and physical activity status (Table 1). All participants completed

RI PT

an Oswestry Disability Index (ODI) (Vianin, 2008), a Visual Analog Score (VAS) of

pain for the lower back region and legs, a Waterloo Footedness Questionnaire (Elias et al, 1998), and a Baecke score of physical activity (Baecke et al, 1982). Institutional Research

SC

Ethics Board approval was obtained prior to data collection. Ultrasound imaging

M AN U

High-resolution ultrasound images of the sciatic nerve and muscles of the lower back and lower limb were obtained using a 6-15 MHz linear transducer (Sonosite MTurbo, Markham, ON) manually held over the skin with the location of imaging marked on the skin surface. For all tests, the experimenter alternated between right and left sides

TE D

until three images had been taken from each side; measures were later averaged across the three images for each side. Imaging in both the axial (view cross-section) and longitudinal (view thickness) planes was completed. Imaging was completed first in a

EP

relaxed state while the participant laid prone on a chiropractic bench with his/her ankles in a neutral position, followed by imaging during standardized submaximal contractions.

AC C

Imaging locations were standardized based on anatomical landmarks. The biceps

femoris and the sciatic nerve were imaged at the level of the posterior midthigh, at the point 25% along a line measured from the popliteal crease to the ipsilateral iliac crest. Longitudinal images allowed for determination of muscle thickness, measured as the linear distance between the superficial and deep fascial planes of the muscle (Figure 1A), and axial images provided a cross sectional view of the sciatic nerve and the biceps

3

ACCEPTED MANUSCRIPT

femoris muscle (Figure 1B). Imaging in this manner has been shown to be reliable for both sciatic nerve cross sectional area (Cartwright et al, 2013) and biceps femoris thickness (Kellis et al, 2009). Note that for all muscles, axial images were used to trace

RI PT

regions of interest, used for the determination of muscle quality, but not muscle cross-

sectional area. The medial gastrocnemius and soleus were imaged at a location 30% of

the tibial length from the popliteal crease to the midpoint of the medial malleolus (Cho et

SC

al, 2013). Medial gastrocnemius and soleus thickness was recorded from the longitudinal image (Figure 1C), and axial images provided a cross sectional view of medial

M AN U

gastrocnemius only (Figure 1D). The paraspinal (combined erector spinae and multifidus) muscle group was imaged at the L2/L3 vertebral level of the lower back. Longitudinal images were taken approximately 2 cm lateral to the midline, so that the spinal facet joints could be clearly identified in the image (Figure 1E). Axial images were recorded

TE D

by spanning the transducer across the spinous processes so that bilateral cross-sectional views of the paraspinal muscles could be recorded (Figure 1F). Last, the biceps brachii was imaged as an area of the body not directly affected by sciatica. This measure was

EP

performed to ensure that the patient and control groups had no baseline differences in muscle contraction or quality. Biceps brachii was imaged at a point 50% along a line

AC C

between the acromion and the elbow crease, in both axial and longitudinal planes. Imaging in a contracted state required that participants perform standardized

submaximal isometric activations of paraspinal, biceps femoris, soleus/medial gastrocnemius and biceps brachii muscles. Three repetitions of each submaximal activation were performed on each side of the body, alternating between the right and left sides to minimize fatigue. During the isometric hold of each activation, a longitudinal

4

ACCEPTED MANUSCRIPT

image of the muscle of interest (in the same location as the relaxed ultrasound imaging) was taken. Paraspinal submaximal muscle activation required participants to perform a unilateral prone arm raise with a 1 kg hand weight to activate the contralateral paraspinal

RI PT

muscle (Figure 2A). This has previously been shown to activate lumbar multifidus to

30% of maximum (Kiesel et al, 2007). Biceps femoris was activated using an isometric prone hip extension with a straight knee (Figure 2B). Activation of soleus and medial

SC

gastrocnemius required participants to rise onto their toes from a standing position,

standardized to a 5 cm heel lift. For biceps brachii activation, participants held a weight

M AN U

(6.8 kg or 4.5 kg, depending on strength capacity) in their hand with their elbow at 90degrees. In all cases, participants used the same weight on both sides of the body, therefore allowing for side-to-side comparison. Data analyses

TE D

Ultrasound image analyses were completed offline by a single experimenter using OsiriX and ImageJ software. The sciatic nerve was traced just outside the hyperechoic ring, and cross sectional area (cm2), mean echo intensity, and mean echo intensity

EP

normalized to fascia echo intensity were recorded. For all axial images of muscle, a region of interest within the cross sectional area was defined for analysis. From this

AC C

region of interest the mean echo intensity was recorded to determine the relative amount of fat or fibrosis infiltration into the muscle; fat and fibrotic tissue can be defined from muscle tissue based on a higher echo intensity (Fukumoto et al, 2011). Mean echo intensity was therefore defined as a metric of muscle quality. Additionally, the mean echo intensity of a fascial region of interest was recorded from each image and used to normalize the mean muscle and nerve echo intensity; this was done to account for any

5

ACCEPTED MANUSCRIPT

potential image-to-image differences in background brightness. Finally, longitudinal images of paraspinal, biceps femoris, soleus, medial gastrocnemius, and biceps brachii muscles (Figure 1A, 1C, 1E) in relaxed and sub-maximally contracted conditions were

RI PT

used to calculate the contraction index [muscle thickness contracted / muscle thickness

relaxed] for each muscle, bilaterally. A higher contraction index indicates that the muscle thickened more during contraction.

SC

Statistics

Normality of data was verified using the Shaprio-Wilk W statistic. One-way

M AN U

mixed model analyses of variance were completed to compare between group (control, LBP-R unaffected leg, and LBP-R affected leg) for each outcome measure. Main effects and interactions were examined. Where appropriate, Tukey-adjusted post-hoc tests of significant effects (p ≤ 0.05) were used. Control participants’ data were averaged between

TE D

their right and left leg, as there were no statistically significant differences between legs, verified using 1-way analysis of variance for each parameter. For LBP-R patients, Pearson correlations were computed between measures of LBP-R severity (ODI, VAS at

AC C

EP

the back, VAS at the affected leg, duration of symptoms), with each outcome measure.

RESULTS

Sciatic nerve

LBP-R patients had significantly greater sciatic nerve CSA on their

radiculopathy-affected side (0.66 cm2), as compared to the unaffected side (0.55 cm2) (p = 0.0001) (Figure 3). Further, the sciatic nerve of control participants (0.57 cm2) was not different in CSA than either the affected or unaffected side of LBP-R patients (Figure 3).

6

ACCEPTED MANUSCRIPT

Analysis of the sciatic nerve mean echo intensity (mean ± SE) demonstrated no significant difference on the affected side of LBP-R patients (69.7 ± 4.1) as compared to the unaffected side (72.6 ± 4.0), and again as compared to control participants (77.5 ±

was normalized to the fascia mean echo intensity. Muscle contraction index

RI PT

3.7) (p = 0.56). There was no alteration of this result when the nerve mean echo intensity

SC

With the exception of the medial gastrocnemius on the unaffected leg of LBP-R patients, all muscles increased in thickness during contraction, demonstrated by a

M AN U

contraction index above one (Figure 4). In the paraspinal and biceps femoris, the contraction index was not significantly different on the LBP-R affected side as compared to unaffected. More distally, the soleus contraction index was significantly lower on the affected side of LBP-R patients (1.04) compared to their unaffected side (1.1) (p = 0.05).

TE D

Neither the medial gastrocnemius nor biceps brachii demonstrated any between-group differences in contraction index. Muscle quality

EP

Muscle mean echo intensity did not demonstrate any between group differences for any of the measured muscles (paraspinal, biceps femoris, medial gastrocnemius or

AC C

biceps brachii) (Figure 5). When muscle echo intensity was normalized to the fascia echo intensity, there was again no significant between-group difference for any muscle. Correlations with severity Across all outcome measures, there were no statistically significant Pearson

correlations (p-value > 0.05 and |r| > ± 0.20) with ODI, VAS at the lower back, VAS at the affected leg, or symptom duration.

7

ACCEPTED MANUSCRIPT

DISCUSSION Ultrasound imaging of the sciatic nerve revealed that LBP-R patients had significantly larger CSA on their radiculopathy-affected side as compared to their

RI PT

unaffected side; confirming our hypothesis for evidence of increased sciatic nerve CSA

on the affected leg of LBP-R patients. However, we do not accept our hypothesis that the affected leg of LBP-R patients would have a larger sciatic nerve CSA than matched

SC

healthy controls, as this difference was not statistically significant. Further, we reject our hypothesis that the sciatic nerve echo intensity would be lower in LBP-R patients,

M AN U

specifically on their affected leg, relative to controls. There were no consistent differences in muscle contraction index, with the exception of soleus, nor any ultrasound imaging evidence of poorer muscle quality in LBP-R patients; therefore, these hypotheses are rejected.

TE D

Sciatic nerve

Sciatic nerve CSA was significantly larger on the radiculopathy-affected side of LBP-R patients, as compared to their unaffected side, but not compared to controls. This

EP

increase in sciatic nerve size in the affected leg of LBP-R patients is likely due to inflammation and edema resulting from chronic nerve compression (Walker et al, 2004).

AC C

Only one previously published study has reported ultrasound measurements of sciatic nerve CSA in LBP-R patients (Kara et al, 2012); in support of our findings, this previous research found a greater sciatic nerve CSA on the affected side relative to the unaffected side; they did not include a control group (Kara et al, 2012). Although there was a difference in sciatic nerve CSA between LBP-R patients on their affected and unaffected legs, there was no significant correlation between nerve

8

ACCEPTED MANUSCRIPT

CSA with measures of LBP-R severity (ODI, VAS) or duration of symptoms. Similarly, previous work did not find correlations with VAS scores; however there were negative correlations between sciatic nerve CSA and duration of symptoms, as well as the Leeds

RI PT

assessment of neuropathic symptoms and signs (LANSS) neuropathic pain score (Kara et al, 2012). It appears that sciatic nerve CSA is an excellent tool to measure and monitor

level of disability of the patient (Kara et al, 2012).

SC

edema and inflammation present in the nerve, but may not fully reflect the severity or

Sciatic nerve mean echo intensity did not significantly differ between control and

M AN U

LBP-R patients on either their affected or unaffected side. A lower nerve mean echo intensity is expected where compressive injury results in nerve inflammation and endoneurial edema (Walker et al, 2004); however no previous research has investigated this in the sciatic nerve. In contrast to more superficial nerves, the sciatic nerve does not

TE D

display a distinct ‘honeycomb’ appearance, therefore ultrasound analyses of nerve density (Tagliafico et al, 2012) or thresholding (Boom and Visser 2012) used in median and ulnar nerve imaging, were not feasible. The lack of significant differences between

EP

groups demonstrated in the sciatic nerve could indicate that mean echo intensity is not as sensitive as the more sophisticated thresholding methods, or that in this LBP-R

AC C

population there were less apparent changes in the nerve fascicular structure than in the previously published work in upper arm neuropathies. Muscle contraction index There was no statistically significant difference in paraspinal contraction index

between control and LBP-R patients on both unaffected and affected legs. The hypothesis of a smaller paraspinal contraction index in LBP-R patients on their affected side was

9

ACCEPTED MANUSCRIPT

based on previous findings of reduced multifidus contraction index in LBP patients relative to controls at L5, but not at more cranial lumbar levels L2 through L4 (Wallwork et al, 2009). Multifidus atrophy with disc-related LBP is quite localized (Barker et al,

RI PT

2004; Campbell et al, 1998), so it is possible that by imaging the paraspinals at L3 in the current study, potential differences that existed in the lower lumbar region were missed. There is MRI evidence of similar magnitudes of atrophy in erector spinae and multifidus

SC

in LBP patients (Ploumis et al, 2011); however a separate CT study in LBP patients

reported atrophy in multifidus but not erector spinae (Danneels et al, 2000). Therefore,

M AN U

imaging of only multifidus may be more locally sensitive to detect changes in LBP-R. The assessment of muscle contraction by comparing thickness in relaxed and contracted states relies on the assumption that the muscle is able to completely relax in prone lying. If LBP-R patients had higher tonic activity in a relaxed state, there would be

TE D

less increase in thickness during a standardized contraction. This could be misinterpreted as a reduced contractibility; however it would merely be a reflection of an inability to relax the muscle. Previous research, however, has indicated that there is likely no

EP

increase in resting paraspinal muscle activity in LBP patients as compared to controls (Kravitz et al, 1981; Nouwen and Bush 1984).

AC C

The contraction index results for biceps femoris were similar to those for the

paraspinals, with no significant difference between groups. It is therefore concluded that LBP-R has no effect on the contraction index of the biceps femoris muscle. There has been no prior research investigating activation of any hamstring muscle in LBP-R patients.

10

ACCEPTED MANUSCRIPT

Contraction index results for medial gastrocnemius were not as hypothesized. First, the LBP-R patients on their unaffected side had a contraction index that was below a value of one, indicating that the muscle became thinner, rather than thicker, upon

RI PT

contraction. The control participants and LBP-R patients on their affected sides both had similar, but small, magnitudes of thickening (4 to 5% relative to relaxed) upon

contraction. None of these measures were significantly different from one another.

SC

Further, one case study LBP-R patient (not included in the n = 17 reported here due to a history of back surgery) with notable unilateral calf atrophy had a nearly identical medial

M AN U

gastrocnemius contraction index on unaffected and affected sides, demonstrating a potential lack of sensitivity of this measure. Relaxed ultrasound images were taken in prone lying, whereas contracted images were taken in a standing position. This may explain why the expected magnitude of thickening of the muscle were not seen in any

TE D

group; however, the procedure was completed in the same manner for LBP-R and control participants, therefore the finding still remains that there were no between-group differences in the medial gastrocnemius contraction index.

EP

In the soleus there was distinct evidence that LBP-R patients did not increase the thickness of their radiculopathy-affected as much their unaffected side, indicating that

AC C

radiculopathy may impair muscle contraction. No prior research has investigated soleus muscle activation or contraction in LBP-R patients; this is the first evidence of impaired lower limb muscular contraction in LBP-R patients. Reduced contraction index has been previously interpreted as impaired neuromotor control (Wallwork et al, 2009), and may reflect an inability or unwillingness to voluntarily activate the muscle.

11

ACCEPTED MANUSCRIPT

Muscle quality There were no significant differences between control and LBP-R patients on their unaffected or affected side for mean echo intensity of any of the muscles measured.

RI PT

It was expected that there would be a greater mean echo intensity of the muscles of the

affected leg of LBP-R patients; this was hypothesized based on the fact that a denervated muscle experiences fat infiltration and fibrosis (Salonen et al, 1985), and both fat and

SC

fibrotic tissue are more hyperechoic (higher echo intensity) than muscle. Evidence of

increased fat infiltration into the lower back musculature (erector spinae and multifidus)

M AN U

in patients in remission of LBP has been detected using MRI to calculate a muscle-fat index (D’Hooge et al, 2012). This was detected at vertebral levels L4 and L5, but not L3 (D’Hooge et al, 2012). Further, previous research has compared the ratio of pure muscle area to total muscle area of multifidus in LBP-R patients using MRI, and found

TE D

differences between patients and controls at L4/L5 and L5/S1, but not L3/L4 (Hyun et al, 2007). In the current study, ultrasound imaging of the paraspinal muscles was completed at L3, therefore we may have not detected differences because (a) alterations in muscle

EP

quality only occurred at lower lumbar levels and not at L3, (b) ultrasound imaging mean echo intensity is not sensitive enough to detect changes in muscle fat content in LBP, or

AC C

(c) LBP-R patients did not have any muscle quality changes relative to controls. Limitations

LBP-R patients had minimal to moderate levels of disability according to the ODI

and VAS scores of pain. Much of the literature that demonstrates differences in LBP patients relative to controls has examined more severely affected LBP patients, therefore the currently investigated LBP-R patient population may not have been severely enough

12

ACCEPTED MANUSCRIPT

affected to elicit detectable differences in some measures. Second, due to limitations of the ultrasound transducer area of view, full muscle CSA was not quantified. Muscle atrophy, or decreased CSA, is one of the most commonly reported measures in MRI, CT,

RI PT

and ultrasound investigations of LBP. It would have been valuable to be able to test for unilateral atrophy in the lower back and lower limb of the LBP-R patients relative to controls.

SC

Conclusions

In conclusion, this research has expanded neuromuscular research of LBP patients

M AN U

into the lower limb to examine structural changes associated with radiculopathy. Clear evidence of sciatic nerve structural changes, markedly increased CSA on the affected relative to unaffected side of LBP-R patients, was seen. Structural changes to the nerve were not associated with impaired paraspinal, biceps femoris or medial gastrocnemius

TE D

contraction or muscle quality; however, LBP-R patients exhibited less soleus thickening during contraction on their affected side. Overall, this work highlights the clinical utility of high resolution ultrasound to detect structural changes in the sciatic nerve, but

AC C

EP

limitations in detecting associated muscular changes in the lower back and lower limb.

13

ACCEPTED MANUSCRIPT

REFERENCES

Andersson GB. Epidemiological features of chronic low-back pain. Lancet 1999;

RI PT

354:581–585.

Baecke JA, Burema J, Frijters JE. A short questionnaire for the measurement of habitual

SC

physical activity in epidemiological studies. Am J Clin Nutr 1982; 36: 936 – 942.

Barker KL, Shamley DR, Jackson D. Changes in the cross-sectional area of multifidus

Spine 2004; 29:E515–9.

M AN U

and psoas in patients with unilateral back pain: the relationship to pain and disability.

Boom J, Visser LH. Quantitative assessment of nerve echogenicity: comparison of methods for evaluating nerve echogenicity in ulnar neuropathy at the elbow. Clin

TE D

Neurophysiol 2012; 123:1446–1453.

Campbell WW, Vasconcelos O, Laine FJ. Focal atrophy of the multifidus muscle in

EP

lumbosacral radiculopathy. Muscle Nerve 1998; 21:1350–1353.

Cartwright MS, Demar S, Griffin LP, Balakrishnan N, Harris JM, Walker FO. Validity

AC C

and reliability of nerve and muscle ultrasound. Muscle Nerve 2013; 47:515 – 521.

Cassidy J D. Saskatchewan health and back pain survey. Spine 1998; 23:1860 – 1867.

Chan ST, Fung PK, Ng NY, Ngan TL, Chong MY, Tang CN, et al. Dynamic changes of elasticity, cross-sectional area, and fat infiltration of multifidus at different postures in men with chronic low back pain. Spine J 2012; 12 :381–388.

14

ACCEPTED MANUSCRIPT

Cho KH, Lee HJ, Lee WH. Reliability of rehabilitative ultrasound imaging for the medial gastrocnemius muscle in poststroke patients. Clin Physiol Funct Imaging 2013; 34: 26 –

RI PT

31.

D'hooge R, Cagnie B, Crombez G, Vanderstraeten G, Dolphens M, Danneels L.

Increased intramuscular fatty infiltration without differences in lumbar muscle cross-

SC

sectional area during remission of unilateral recurrent low back pain. Manual Therapy 2012; 17:584–588.

M AN U

Danneels LA, Vanderstraeten GG, Cambier DC, Witvrouw EE, De Cuyper HJ. CT imaging of trunk muscles in chronic low back pain patients and healthy control subjects. Eur Spine J 2000; 9:266–272.

Elias LJ, Bryden MP, Bulman-Fleming MB. Footedness is a better predictor than is

TE D

handedness of emotional lateralization. Neuropsychologia 1998; 1: 37 – 43.

Fukumoto Y et al. Skeletal muscle quality assessed from echo intensity is associated with

AC C

– 1525.

EP

muscle strength of middle-aged and elderly persons. Eur J Appl Physiol 2011; 112: 1519

Hyun JK, Lee JY, Lee SJ, Jeon JY. Asymmetric atrophy of multifidus muscle in patients with unilateral lumbosacral radiculopathy. Spine 2007; 32:598–602.

Kara M, Ozcakar L, Tiftik T, Kaymak B, Ozel S, Akkus S, et al. Sonographic evaluation of sciatic nerves in patients with unilateral sciatica. Arch Phys Med Rehabil 2012; 93:1598–1602.

15

ACCEPTED MANUSCRIPT

Kellis E, Galanis N, Natsis K, Kapetanos G. Validity of architectural properties of the hamstring muscles: Correlation of ultrasound findings with cadaveric dissection. J

RI PT

Biomech 2009; 42:2549–2554.

Kiesel KB, Uhl TL, Underwood FB, Rodd DW, Nitz AJ. Measurement of lumbar

2007; 12: 161 – 166.

SC

multifidus muscle contraction with rehabilitative ultrasound imaging. Manual Therapy

Konstantinou K & Dunn KM. Sciatica Review of Epidemiological Studies and

M AN U

Prevalence Estimates. Spine 2008; 33: 2464–2472.

Kravitz E, Moore ME, Glaros A. Paralumbar muscle activity in chronic low back pain. Arch Phys Med Rehabil 1981; 62:172-176.

TE D

Nouwen A, Bush C. The relationship between paraspinal EMG and chronic low back pain. Pain 1984; 20:109-123.

EP

Ploumis A, Michalidis N, Christodoulou P, Kalaitzoglou I, Gouvas G, Beris A. Ipsilateral atrophy of paraspinal and psoas muscle in unilateral back pain patients with

AC C

monosegmental degenerative disc disease. British Journal of Radiology 2011; 84:709– 713.

Salonen V, Lehto M, Kalimo H, Penttinen R, Aro H. Changes in intramuscular collagen and fibronectin in denervation atrophy. Muscle Nerve 1985; 8:125–131.

16

ACCEPTED MANUSCRIPT

Tagliafico A, Tagliafico G, Martinoli C. Nerve density: a new parameter to evaluate peripheral nerve pathology on ultrasound. Preliminary study. Ultrasound in Medicine &

RI PT

Biology 2012; 36:1588–1593.

Vianin M. Psychometric properties and clinical usefulness of the Oswestry Disability Index. Journal of Chiropractic Medicine 2008; 7:161 – 163.

M AN U

Clinical Neurophysiology 2004; 115:495–507.

SC

Walker FO, Cartwright MS, Wiesler ER, Caress, J. Ultrasound of nerve and muscle.

Wallwork TL, Stanton WR, Freke M, Hides JA. The effect of chronic low back pain on size and contraction of the lumbar multifidus muscle. Manual Therapy 2009; 14:496–

AC C

EP

TE D

500.

17

ACCEPTED MANUSCRIPT

TABLES

= 17) and controls (n = 17).

Sex

Baecke

Age

ODI (%)b

Height (m) Mass (kg) scorea

(M:F) 44.2 ± 14.9 6:11

1.69 ± 7.7

69.5 ± 9.2

8.2 ± 1.4

19.9 ± 12.8 2.6 ± 2.3

1.8 ± 1.2

Control 44.2 ± 15.7 6:11

1.72 ± 7.9

69.1 ± 10.8

8.4 ± 1.4

0.7 ± 1.3

0.3 ± 0.4

M AN U

LBP-R

a

Duration

VAS backc VAS legc

SC

Group

RI PT

Table 1: Participant characteristics (mean ± SD) of matched unilateral LBP-R patients (n

0.3 ± 0.4

(months) 126 ± 143

Baecke score of physical activity for work, sport and leisure activity Oswestry Disability Index, on a percentage scale; scores from 0-20% indicate minimal disability, 20-40% indicate moderate disability, 40-60% severe disability c Visual Analog Scale of pain recorded at the back and the affected leg on separate scales, on a scale of 0-10. A score of 0-0.4 indicates no pain, 0.5-4.4 indicates mild pain, 4.5-7.4 indicates moderate pain, 7.5-10 indicates severe pain

AC C

EP

TE D

b

18

ACCEPTED MANUSCRIPT

FIGURE CAPTIONS

SC

RI PT

Figure 1: Representative ultrasound images of [A] biceps femoris longitudinal, [B] biceps femoris axial and sciatic nerve (black arrow), [C] medial gastrocnemius and soleus longitudinal, [D] medial gastrocnemius and soleus axial, [E] paraspinals longitudinal, and [F] paraspinals axial, with SP (spinous process) and R (right) and L (left) sides of the body. In longitudinal images, the vertical line indicates the thickness measurement between the inferior and superior fascial planes of the muscle (medial gastrocnemius, soleus, biceps femoris) or between the facet joint (FJ) and superior fascial plane of the muscle (paraspinals). In axial images, the dashed line surrounds the muscle region of interest for determination of muscle quality. Top is superficial, and bottom is deep.

M AN U

Figure 2: Representation of the submaximal activation tasks for paraspinal [A] and biceps femoris [B] muscles. The paraspinal activation required the participants to lift their extended arm off of the table so that the wrist was 5 cm above the table, while holding a 1 kg weight in their hand. The biceps femoris activation required the participants to extended their leg at the hip so that their ankle was 15 cm above the table. Figure 3: Mean (± SE) sciatic nerve cross sectional area (cm2) for control, LBP-R patients on their unaffected leg, and LBP-R patients on their affected leg. * p < 0.05

TE D

Figure 4: Mean (± SE) ultrasound muscle contraction index of the paraspinal, biceps femoris (BF), medial gastrocnemius (MG), soleus (Sol) and biceps brachii (BB) muscles. Contraction index represents [thickness contracted / thickness relaxed]. * p = 0.05

AC C

EP

Figure 5: Muscle (± SE) mean ultrasound echo intensity for control, LBP-R patients on their unaffected leg, and LBP-R patients on their affected leg.

19

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT

• •

AC C

EP

TE D

M AN U

SC

• •

Ultrasound imaging of patients with chronic lower back pain and radiculopathy. Patients had swollen sciatic nerves, compared to controls. Less submaximal muscle thickening during contraction in the soleus of patients. No evidence of poorer muscle quality in patients. This is the first evidence of neuromuscular changes in the lower limb of patients.

RI PT



Neuromuscular ultrasound imaging in low back pain patients with radiculopathy.

Patients suffering from chronic low back pain with associated radiculopathy (LBP-R), or sciatica, experience neuromuscular symptoms in the lower back ...
3MB Sizes 2 Downloads 11 Views