Lumbar Radiculopathy

Definition/Description

Lumbar radiculopathy is a disease in wich pain is caused in the lower back and hip radiating down the back of the thigh into the leg. It is caused by damage to one of the lower spines, ranging from L1 to S1. This damage is caused by compression of the nerve roots which exit the spine. The compression can lead to tingling, radiating pain, numbness, paraesthesia and occasional shooting pains. Radiculopathy can occur in any part of the spine, but it is most common in the lower back (lumbar radiculopathy) and in the neck (cervical radiculopathy). It is less commonly found in the middle portion of the spine (thoracic radiculopathy).[1]

Radiculopathy is not the same as “radicular pain” or “nerve root pain”. Radiculopathy and radicular pain commonly occur together, but radiculopathy can occur in the absence of pain and radicular pain can occur in the absence of radiculopathy.[2]

Radiculopathy can be defined as the whole complex of symptoms that can rise from nerve root pathology, including anaesthesia, paresthesia, hypoesthesia, motor loss and pain.

Radicular pain and nerve root pain can be defined as a single symptom (pain) that can arise from one or more spinal nerve roots.[3] Lumbar radiculopathy is a disorder of the spinal nerve roots from L1 to S1.

Clinically Relevant Anatomy

The vertabral column consists of 33 vertebrae divided in five regions: a cervical, thoracic, lumbar, sacral and coccygeal region. The lumbar region counts 5 vertebrae and is located in the lower back between the thorax and sacrum. The lumbar vertebrae have massive bodies that are much larger than the other vertabrae.[4]The foramina vertebralis is also bigger and the facies articularis of the processus articularis inferior are turned outwards. These structures of the lumbar vertebrae have been developed to allow forward and backward movements of the lumbar spine.[5]

The intervertebral discs provide a strong attachment between the vertebral bodies. They are important to supply movement between neighboring vertebrae but they also have a bouncy deformability that allows them to serve as shock absorbers. Each intervertebral disc consist of an annulus fibrosus, an outer fibrous part that is composed of concentric lamellae and the nucleus pulposus.[6] (LOE 5)

The lumbar plexus originates from the first four lumbar ventral rami and forms a triangular shape. The first lumbar ventral ramus is divided in the n.iliohypogastricus and the n.ilioinguinalis. They go through the anterior part of the m. quadratus lumborum. These nerves are the only elements of the lumbar plexus in contact with this muscle. The n.genitofemoralis and the n.cutaneous femoralis lateralis originates from the second lumbar ventral ramus (L2-L3).[7]

The n.genitofemoralis descended on the ventral aspect of the m. psoas major while the n.cutaneous femoralis lateralis crossed the lateral border of the m.psoas major.[6][7]

The large posterior divisions of the ventral rami of L2-L3-L4 unites to the n.femoralis. These nerve leaves the m.psoas major from the postero-lateral border. Then the nerve travels in the gutter between the m.psoas major and the m.iliacus.[6]

The anterior division of L2-L3-L4 are smaller and give rise to the n.obturatorius (L2-L3-L4). The n.obturatorius is the innermost nerve of the plexus lumbalis. This nerve leaves the m.psoas major on his interna land posterior side between L5 and S1.[6][7](LOE 5)

The n.isciadicus originates from the L4-S3 roots in the form of two nerve trunks. These two nerves are the n.tibialis and the n.peroneus communis.[8]  

Epidemiology /Etiology

Lower back pain is severely common in general population, but lumbar radiculopathy has only been reported with an incidence of 3 to 5%. [3]
5-10% of patients with low back pain have sciatica. the annual prevalence of disc related sciatica in general population is estimated at 2,2%. [9]

Prognosis is in the most cases favourable, the most pain and related disabilities resolves within two weeks.[9](LOE 1A) But at the same time a substantial group (30%) continues to have pain for one year or longer.[9]

Lumbar radiculopathy is a disease that commonly arises with significant socioeconomical consequences. The discal origin of a lumbar radiculopathy incidence is around 2%. Out of a 12.9% incidence of low back complaints within working population, 11% is due to lumbar radiculopathy.[10] (LOE 5)
The prevalence of lumbosacral radiculopathy has been situated from 9.9% to 25%.[11]

Risk factors for radiculopathy are activities that place an excessive or repetitive load on the spine. Patients involved in heavy labour or contact sports are more prone to develop radiculopathy than those with a more sedentary lifestyle.  

Radiculopathy is caused by compression or irritation of the nerves with resultant pain, weakness, and/or sensor impairment in the affected nerve root, may be from direct trauma or from chemical irritation to the affected nerve root[11]. This can be due to mechanical compression of the nerve by a disk herniation, a bone spur (osteophytes) from osteoarthritis, or from thickening of surrounding ligaments. As people age, their spines are subject to increasing degeneration which can cause herniated discs and similar problems such as spinal stenosis, leading to lumbar radiculopathy.

Lumbar spinal stenosis can be caused by congenital abnormalities or degenerative changes. 

These degenerative changes are a result from either a trauma, infection or in rare cases tumours. Lumbar stenosis can be described as the narrowing of the spinal canal and compressing the nerve caused by the underlying causes as mentioned above.[3]
Scoliosis can cause the nerves on one side of the spine to become compressed by the abnormal curve of the spine.

Clinical Presentation

Lumbar radiculopathy is caused by:

  • herniated disc with nerve root compression (90%). [9]
  • lumbar stenosis [9] 
  • tumours (less often)[9]
  • underlying diseases like infections. (Imaging is indicated here) [9]
  • lateral recess stenosis and radiculitis [2]


In patients under 50 years, a herniated disc is the most frequent cause. After the age of 50, radicular pain is often caused by degenerative changes in the spine (stenosis of the foramen intervertebrale). [3] Risk factors for acute lumbar radiculopathy are:[9]

  • age (peak 45-64 years)
  • smoking
  • mental stress
  • strenuous physical activity (frequent lifting)
  • driving (vibration of whole body)

Indication for sciatica / symptoms: [9]

  • unilateral leg pain greater than low back pain, leg pain follows a dermatomal pattern[9](LOE 1A) [4] (LOE 2B)
  • pain traveling below knee to foot or toes
  • numbness and paraesthesia in the same area
  • traight leg raise positive, induces more pai

Clinical presentation depends on the cause of the radiculopathy and which nerve roots are being affected. Also important is the nature (sharp, dull, piercing, throbbing, stabbing, shooting, burning) and localisation of the pain[5](LOE 1C). Some patients reports beside radicular leg pain also neurological signs such as paresis, sensory loss or loss of reflexes. If not present, this is not a radiculopathy.

Clinical presentation for radiculopathy from each lumbar nerve root: 
Dermatomes.jpg
Nerve Root Dermatomal area Myotomal area Reflexive changes
L1 Inguinal region Hip flexors
L2 Anterior mid-thigh Hip flexors
L3 Distal anterior thigh Hip flexors and knee extensors Diminished or absent patellar reflex
L4 Medial lower leg/foot Knee extensors and ankle dorsiflexors Diminished or absent patellar reflex
L5 Lateral leg/foot Hallux extension and ankle plantar flexors Diminished or absent achilles reflex 
S1 Lateral side of foot Ankle plantar flexors and evertors Diminished or absent achilles reflex 

Differential Diagnosis

Radicular syndrome/ Sciatica: a disorder with radiating pain in one or more lumbar or sacral dermatomes, and can be accompanied by phenomena associated with nerve root tension or neurological deficits.[2]

  • Pseudoradicular syndrome
  • Thoracic disc injuries
  • Lumbosacral disc injuries
  • Low back pain
  • Spinal stenosis
  • Cauda equina
  • Inflammatory/metabolic causes[10]: Diabetes, Ankylosing spondylitis, Paget’s disease, Arachnoiditis, Sacroidosis
  • trochanteric bursitis
  • intraspinale synovial cysts

Diagnostic Procedures 

Clinical evaluation:

  • X-rays: to identify the presence of a trauma or osteoarthritis and early signs of a tumor or an infection
  • EMG: useful in detecting radiculopathies but they have limited utility in the diagnosis. In patients with clinical suspicion of lumbosacral radiculopathy and normal MRI findings, EMG may help in diagnosing nerve root involvement in patients with otherwise unexplained leg pain.[9]
  • MRI: used to see if disc herniation and nerve root compression are present in patients with clinical suspicion of lumbosacral radiculopathy.[11]

Outcome measures

  • Roland Morris Disability Questionnaire (RMDQ):
    The Roland Morris Disability Quenstionnaire assess changes in functional status after treatment in patients with low back pain. The Questionnaire is a widly used health status.[2][3]
  • Back Pain Functional Scale:
    A scale for self-report measure that evaluates functional ability in people with back pain.[4]
  • The Maine-Seattle Back Questionnaire: 
    A 12-item disability questionnaire for evaluating patients with lumbar sciatica or stenosis.[5] 
  • Fear Avoidance Belief Questionnaire (FABQ): this questionnaire is developed by Waddell to investigate fear-avoidance beliefs among LBP patients in the clinical setting.[6]
  • Oswestry Low Back Pain Disability Questionnaire:
    considered as ‘the golden standard’ to measure the permanent functional disability of the lower back. [2]
  • The Quebec back pain disability scale (QBPDS):
    used to measure the functional disability for patients with lower back pain. [3]

Examination

Diagnosed by history taking and physical examination.[9] Motor, sensory and reflex function should be assessed to determine the affected nerve root level.[9]
If the patients reports the typical unilateral radiating pain in the leg and there is one or more positive neurological test result the diagnosis of sciatica seems justified.[9]
Diagnosed by history taking and physical examination.[9]Motor, sensory and reflex function should be assessed to determine the affected nerve root level. [7]

Clinical evaluation of lumbosacral radiculopathy begins with:

Medical history (type, location and duration of symptoms, presence of subjective weakness and dysesthesia, current therapy, dermatomal radiation, absence of work) and physical examination: dermatomal sensory loss, myotomal weakness, straight leg raise[8][9], Crossed Straight Leg Raise Test, Femoral Nerve Stretch Test and reflexes.
if the patients report the typical unilateral radiating pain in the leg and there is one or more positive neurological test result, the diagnosi of sciatica seems justified. [9]

Straight Leg Raise test (Lasègue test):
The best known clinical test is the straight-leg raising test[10] The supine SLR is more sensitive than the seated SLR when it comes to the diagnosis of lumbar disc herniation with radiculopathy. A pooled sensitivity for straightleg raising test was 0. 91 (95% CI 0.82-0.94), a pooled specificity 0.26 (95% CI 0.16-0.38)[10]. The test is based on stretching of the nerves in the spine[11]

Crossed Straight Leg Raise Test (Crossed Lasègue test):

A test for the containment and exclusion of lumbar radiculopathy. For the cross straight leg raising test a pooled sensitivity was 0.29 (95% CI 0.24-0.34), pooled specificity was 0.88 (95% CI 0.86-0.90)[10](LOE 1A). The test is based on stretching of the nerves in the spine.[11](LOE 1A)
Femoral Nerve Stretch Test:
For the Femoral Nerve Stretch Test, the patient lies prone with the knee passivley flexed to the thigh. The test is positive if the patient experiences anterior thigh pain. This test causes a downward and slightly lateral movement of the femoral nerve, its nerve root and the intradural rootlet.[9] (LOE 4)

Specific vertebral level
To diagnose an L4 radiculopathy the clinician placed emphasis on the femoral nerve stretch test, the straight leg raise test, the knee reflex, sensory loss in the L4 dermatome and the muscle power for the ankle dorsiflexion.

To diagnose an L5 radiculopathy, the clinician focused on the straight leg raise test, sensory loss in the L5 dermatome, and the muscle power for the hip abduction, ankle dorsiflexion, ankle eversion, and the big toe extension.

For an S1 radiculopathy the clinician emphasized the straight leg raise test, the ankle reflex, sensory loss in the S1 dermatome, and the muscle power for hip extension, knee flexion, ankle plantarflexion, and ankle eversion.[9]

[12]
[13]

Medical Management

Lumbar radicular syndrome can be treated in a conservative or a surgical way. The international consesus says that in the first 6-8 weeks, conservative treatment is indicated.[3]. Surgery should be offered only if complaints remain present for at least 6 weeks after a conservative treatment.[4] .

Conservative

The conservative treatment is primarily aimed at pain reduction and includes the use of analgesics, non-steroidal anti-inflammatory drugs[5], muscle relaxants and oral steroids (prednisone)[9] . But also other conservative treatments, such as traction, manipulation, ultrasound, hot packs, acupuncture[6], or corsets have been widely discussed. Also the value of bed rest was examined in patients with sciatica; results suggest that advice for bed rest is not as effective as advice to stay active for people with low-back pain.[7] . By research the majority of radiculopathy patients respond well to this conservative treatment, and symptoms often improve within six weeks to three months.

There is a new study that has been published in 2016. This study reveals that appropriate use of EI (= epidural injections) to treat sciatica could significantly improve the pain score and functional disability score, which leads to significant decrease in surgical rate. Additionally, EI’s with or without steroids are clinically effective, fast, safe and a less expensive treatment method as compared to surgical intervention. [7]

In a study with 532 patients to evaluate the effect of non-steroidal anti-inflammatory drugs, or Cox-2 inhibitors, we can conclude that the drugs have a significant effect on acute radicular pain compared with placebo.[5] But other studies say that there are no positive effects on lumbar radicular pain.[8]

There are several studies that have investigated the effect of acupuncture in people with acute lumbar radicular pain. Acupuncture would have a positive effect on the pain intensity, and pain threshold.).[6]

Among patients with acute lumbar radiculopathy, oral steroids (prednisone) will relieve them from pain and improve function.[10]

In an study entitled ‘Effectiveness of conservative treatments for the lumbosacral radicular syndrome: a systematic review’[2], 30 trials were included to evaluate the effects of injections, traction, physical therapy and manipulation as treatment for the lumbosacral radicular syndrome. They have come to the following conclusions:

  • At short term there is no evidence in favour of traction when compared to sham (fake) traction or other conservative treatments.[8]
  • At short term there is no evidence in favour of physical therapy compared to inactive treatment (bedrest), other conservative treatments or surgery.[9] (LOE 1B)
  • At short term there is no evidence in favour of manipulation compared to other conservative treatments or chemonucleolysis.[2]

Surgical

A surgical intervention for sciatica is called a discectomy and focuses on removal of disc herniation and eventually a part of the disc. [9]

90% of all patients who have had surgery for lumbar disc herniation underwent discectomy alone, although the number of spinal fusion procedures has greatly increased. Additionally, the complication rate of simple discectomy is reported at less than 1%. Next to simple discectomy and spinal fusion, there are 3 other surgical treatments which can be applied in patients with disc herniation: 1) chemonucleolysis 2) percutaneous discectomy 3) microdiscectomy. [5]

When we compare the surgical (50%) vs nonoperative (50%) treatment for lumbar radicular pain in a study with 501 patients, we can conclude that patients in both the surgery and the nonoperative treatment groups improved substantially over a 2-year period.[11] However, in the group who received the conservative treatment (active physical therapy, education/counseling with home exercise instruction, and nonsteroidal anti-inflammatory drugs), 30% of the patients underwent the surgery at the end of the study.[11]

Physical Therapy Management

To reduce the pain we need to take care of the underlying problem. The main problem is that the nerve is pinched in the intervertebral foramen.

In an acute phase there is moderate evidence for spinal manipulationfor symptomatic relief[7][8] . Only low level evidence was found for manipulations of chronic lumbar radiculopathy. [10] Because the pain is due to a narrowing of the intreverterbral foramen a normal traction of the lower spine will also relieve the pain [5]

Beside relieving the pain the patient also needs muscle training, more specific stabilisation. In the literature you can find a lot of exercises for people with low back pain. The Pilates exercises are not only working for stabilisation but also for the awareness of the body.[9] An exercise that is known to relieve the pain in the lower back is the McKenzie exercise. [11] The main goals of the therapy are reducing the pain. A first thing the patient needs to learn is the awareness of his body (back school) [5] it reduces the pain.

Exercise therapy can have a beneficial effect. It is often a first line treatment. However, until now, evidential value for this is lacking.[4][5]. In a randomised study, they wanted to demonstrate what the effect was after a 52 week rehabilitation program; first exercise therapy in combination with conservative therapy and on the other hand only the conservative treatment. (79% versus 56% Global Perceived Effect, respectively). A systematic review conclude that traction and exercise therapy are effective.[8]

Physical therapy can include mild stretching and pain relief modalities, conditioning exercise and ergonomic program. A comprehensive rehabilitation program includes postural training, muscle reactivation, correction of flexibility and strength deficits, and subsequent progression to functional exercises.[14]

Moderate evidence favors stabilization exercises over no treatment, manipulation over sham manipulation, and the addition of mechanical traction to medication and electrotherapy. There was no difference among traction, laser, and ultrasound.[11]

When a patient complains about instability, core stability is really important. Core stabilisation exercise (CSE) with the abdominal drawing-in manoeuvre (ADIM) technique are commonly used. These exercises activate the deep abdominal muscles with minimal activity of the superficial muscles.[8]

Core stabilisation exercises

Isolated transversus abdominis and lumbar multifidus training
1. Train transversus abdominis muscle activation in a prone lying position without spinal and pelvic movements for 10 seconds with ten repetitions. Keep respiration normal. You gently draw in the lower anterior abdominal wall below the navel level (abdominal drawing-in maneuver) with supplemented contraction of pelvic floor muscles, control your breathing normally, and have no movement of the spine and pelvis while lying prone on a couch with a small pillow placed beneath your ankles. Train lumbar multifidus muscle activation in an upright sitting position. You raise the contralateral arm while performing the abdominal drawing-in maneuver in a sitting position on a chair.

Integrated transversus abdominis and lumbar multifidus training light activities
2. Perform cocontraction of transversus abdominis and lumbar multifidus muscles while sitting on a chair. You use the index and middle fingers to palpate contraction of transversus abdominis muscle and the opposite two fingers to palpate contraction of lumbar multifidus muscle. This exercise progresses from 10- to 60-second holds of cocontraction for ten repetitions. Train cocontraction of these muscles with trunk forward and backward while sitting on a chair and keeping your lumbar spine and pelvis in a neutral position. The second exercise this week required 10-second holds with ten repetitions.

3. Perform cocontraction of the two muscles in a crooked lying position with both hips at 45 degrees and both knees at 90 degrees. Then you abduct one leg to 45 degrees of hip abduction and hold it for 10 seconds.
Train cocontraction of these muscles in a crooked lying position with both hips at 45 degrees and both knees at 90 degrees. Then you slide a single leg down until the knee is straight, maintain it for 10-second holds and then slide it back up to the starting position.

4. Perform cocontraction of the two muscles while sitting on a balance board. You perform cocontraction of the muscles with trunk forward, backward, and sideways while sitting on a balance board and keeping your lumbar spine and pelvis in a neutral position. You perform each pose for 10-second holds with ten repetitions.

Integrated transversus abdominis and lumbar multifidus training heavier activities
5. Perform cocontraction of the two muscles while raising the buttocks off a couch from a crooked lying position until your shoulders, hips, and knees are straight. You sustain this pose for 10 seconds and then lower the buttocks back down to the couch with ten repetitions.
Train muscle cocontraction while raising the buttocks off a couch from a crooked lying position with one leg crossed over the supporting leg. You raise the buttocks off the couch until the shoulders, hips, and knees are straight. You sustain this pose for 10 seconds and then lower the buttocks back down to the couch with ten repetitions.

6. Perform cocontraction of the two muscles while raising a single leg from a four-point kneeling position and keeping your back in a neutral position. You sustain this pose for 10 seconds and then return the leg to the starting position with ten repetitions.
Train muscle cocontraction while raising an arm and alternate leg from a four-point kneeling position and keeping your back in a neutral position. You sustain this pose for 10 seconds and then return to the starting position with ten repetitions.

7. Perform cocontraction of the two muscles in a standing position while a mini ball is behind your upper back and against the wall. You flex the hip and knee of one leg to 90 degrees. Sustain this pose for 10 seconds and then return to the starting position with ten repetitions.
Train the muscle cocontraction in a standing position with ankle movement. Perform ankle movement in the forward-backward direction while keeping your lumbar spine in a neutral position. Sustain this pose for 10 seconds and then return to the starting position with ten repetitions.

Integrated transversus abdominis and lumbar multifidus training in pain aggravating activities
8–10. Perform muscle cocontraction while walking at normal, faster and fastest speed for 5 minutes at weeks 8, 9, and 10 respectively. In addition, choose two aggravating activities or tasks that you anticipate would cause pain or instability and perform muscle cocontraction while doing these activities or tasks without having pain. Each aggravating activity or task is performed for 2.5 minutes.

References

  1. Trond Iversen et al.;Accuracy of physical examination for chronic lumbar radiculopathy; BMC musculoskeletal disorders; 2013; 14: 206 LOE: 1B
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Nikolai Bogduk ;On the definition and physiology of back pain, referred pain, and radicular pain; University of Newcastle; 2009; 17-19:206 LOE: 5
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Pain patterns and descriptions in patients with radicular pain: Does the pain necessarily follow a specific dermatome?;Donald R Murphy*1,2,3, Eric L Hurwitz4, Jonathan K Gerrard5 and Ronald Clary6 LOE: 3B
  4. 4.0 4.1 4.2 4.3 4.4 Keith L. Moore et al.; Clinically oriented anatomy seventh edition; Wolters Kluwer; p 556-632; 2014; LOE: 5
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 Valentyn Serdyuk; Scoliosis and spinal pain sydrome: new understanding of their origin and ways of successful treatment;Byword books; p47; 2014 LOE: 5
  6. 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Winnie A. P. et al.;The inguinal paravascular technic of lumbar plexus anesthesia: the 3 in 1 block; Anesthesia & Analgesia; p989-996; 1973 LOE: 5
  7. 7.0 7.1 7.2 7.3 7.4 7.5 7.6 Juliana Farny et al.; Anatomy of the posterior approach to the lumbar plexus block; Canadian Journal of Anaesthesia; p 480-485; 1994 LOE: 5
  8. 8.0 8.1 8.2 8.3 8.4 8.5 8.6 Jerry D. Vloka et al.; The division of the scatic nerve in the popliteal fossa: anatomical implications for popliteal nerve blockade; departemnts of clinical anesthesiology;1992: 215-7; 2001 LOE: 3B
  9. 9.00 9.01 9.02 9.03 9.04 9.05 9.06 9.07 9.08 9.09 9.10 9.11 9.12 9.13 9.14 9.15 9.16 9.17 9.18 9.19 9.20 9.21 9.22 Coster S., de Bruijn S.F.R.M., Tavy D.L.J.,Diagnostic value of history, physical examination and needle electromyography in diagnosing lumbosacral radiculopathy, Journal of neurology, 2009 LOE: 4
  10. 10.0 10.1 10.2 10.3 10.4 10.5 10.6 Tarulli AW, Raynor EM. Lumbosacral radiculopathy. Neurol Clin 2007; 25(2): 387–405. LOE: 5
  11. 11.0 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8 Kennedy DJ et al. The role of core stabilization in lumbosacral radiculopathy. Phys Med Rehabil Clin N Am. 2011 Feb LOE: 4
  12. Physiotutors. Myotomes Lower Limb | Peripheral Neurological Examination. Available from: https://www.youtube.com/watch?v=ptO9ZvsUPDg
  13. Physiotutors. Dermatomes Lower Limb | Peripheral Neurological Examination. Available from: https://www.youtube.com/watch?v=SzAyUsA25MQ
  14. Kennedy DJ et al. The role of core stabilization in lumbosacral radiculopathy. Phys Med Rehabil Clin N Am. 2011 Feb LOE: 4