The sciatica is the clinical translation of suffering from a root (L5 or SI) of the sciatic nerve in the lumbar spine. The origin of this monoradicular pain is usually compression, itself a row, in the vast majority of cases, a herniated disc.More rarely, this compression is related to another pathology “mechanical” (arthrosis, spondylolisthesis, etc.), optionally associated with disc pathology, or an “inflammatory” pathology (sciatica “symptomatic” or “secondary” Original especially tumor or infectious).

Lomboradiculaires other pathologies (cruralgia, neuralgia fémorocutanée) is the differential diagnosis of sciatica.


In practice, the approach to radicular pain allure of a lower limb is threefold: to affirm the sciatica; assert its discogenic; and search a deficit neurological complication, possibly warranting urgent treatment. These three steps are of course simultaneous bedside.

Physical examination:


He stated (see Spinal Pain):

– Installation mode pain and terrain of occurrence;

– Mechanical or inflammatory schedule;

– Seniority of pain, his progressive profile, its functional impact, topography;

– A possible impulsivity lumbar pain and / or sciatic cough, sneeze or the defecation;

– The possible existence of general signs, sphincter disorders or extraspinal clinical manifestations.

The precise description of the topography possibly clarifies immediately concerned root:

– Sciatica L5: buttock (sometimes painful arrow groin), posterolateral opposite thigh, outer side of the knee, anterolateral aspect of the leg, lateral malleolus (sometimes with pain strap around the ankle), dorsum of the foot and first toe;

– Sciatica SI: buttocks, posterior thigh, popliteal, calf, heel, sole and outer edge of the foot until the last two toes.

This is especially the foot, where the pain is associated with paresthesia willingly, that the topographical distinction between L5 and SI is possible.

Sometimes sciatica pain has a more unusual path:

– Truncated sciatica, usually in the thigh, more often than SI L5;

– Sciatica suspended, with pain in the buttock, thigh disappearing and taking in the leg or foot, of diagnosis more difficult.

Physical examination:

He’s looking for :

– A contraction of the paraspinal muscles with possible analgesic deviation bayonet and / or lumbar blocking anteflexion;

– A Lasegue, which is the acute onset or exacerbation of spontaneous sciatica pain to passive elevation of the lower limb in extension, with the patient supine. The angle between the lower limb and the plane of the bed is measured and proves a good monitoring element of evolution.

The existence of a Lasegue Crusader (Wake Up sciatic pain by operating Lasègue on lower limb contralateral) is highly suggestive of disk herniation. The sign of Lasegue root may be replaced by a sign of lumbar Lasegue less “specific” of disc pathology;

– Painful midpoints and latérovertébraux on palpation or a sign of the bell;

– The presence of objective neurological signs: a decrease or disappearance Achilles reflex, indicating a compression of the SI root (no deep tendon reflex corresponding to L5)

– Superficial hypoesthesia in maneuvering the peak-key, usually discrete and distal (foot)

– Above all, motor weakness, rarely significant (usually between 3 and 4 side), usually distal, high value-locator:

• L5 in the territory, where the existence of paresis is common for one or more of the following muscles: extensor hallucis longus, extensor digitorum longus, lateral peroneal (external rotation of the foot), tibialis anterior (dorsiflexion foot) and gluteus medius (thigh abduction). For the record, the highlight of a defi cit of the gluteus medius, combined with that of other above-mentioned muscles, helps affirm the root origin, as opposed to distal cit challenge of a lesion of the peroneal, which obviously respects the gluteus medius,

• S1 in the territory, where the existence of a motor impairment is rarer: flexor hallucis longus, flexor of the toes, plantar flexion of the foot, tibialis posterior, triceps sural;

– A compression of the cauda horse sphincter disorders, hypoesthesia in the saddle, hypotonia of the anal sphincter;

– Finally, the clinical examination must be complete, especially if a secondary sciatica is suspected.

Additional examinations first line:

In the absence of gravity waves (significant neurological deficit or Quick Install, syndrome-tail horse) or suspicion of secondary sciatica, it is not necessary to use additional explorations in a context of sciatica common early in evolution.For some, it is worth asking at least:

– A metering sedimentation rate;

– Some standard radiographs of the lumbar spine + clichés face and profile of the pelvis.

Differential diagnosis:

The diagnosis of sciatica, mainly clinical, is usually easy. However, before the state, should be eliminated:

– Some non-neurological locoregional disease;

– Other lomboradiculaires pathologies;

– Exceptional non radicular sciatica.

Locoregional non-neurological diseases:

Hip diseases, particularly osteoarthritis can cause pain projected to the rear side and / or outer thigh, rarely exceeding the knee. In this context, tendinitis insertion trochanteric

the average gluteal tendon readily manifested by painful radiation to the outside of the thigh and knee, or even of the leg, which can be mistaken for sciatica L5.

Pathologies inflammatory sacroiliac are causing buttock pain, often supplemented with radiating pain in the posterior thigh.

Subsequent joint syndromes, mainly L4 / L5 and L5 / S1, reflecting the suffering of the facet joints most often osteoarthritic origin, willingly associate with low back pain (see Spinal Pain) projected pain in the buttocks, trochanteric regions the groin and back of thighs.

The claudication of chronic peripheral arterial disease is usually easily distinguished from lameness of sensorimotor root origin.

Lomboradiculaires other pathologies:

The cruralgie is, after sciatica, the most common root pathology in lower limb.

It differs from sciatica by:

– The topography of pain: anterior thigh and knee of the internal (L3 root) or anterolateral aspect of the thigh, knee anterior and antero-medial leg (L4 root);

– Lack of Lasegue but the revival of spontaneous radicular pain to maneuver Leri: leg flexion on the thigh of a patient in the prone position;

– The reduction or abolition of the patellar reflex, especially when cruralgie L4;

– The possible existence of a challenge cit engine: psoas (flexion of the thigh on the trunk) for infringement L3, quadriceps (knee extension) or tibialis anterior Breach L4.

Lomboradiculaires other diseases are much rarer:

– Obturator neuralgia (L2 and L3): pain inside thigh ± challenge cit hip adductors;

– Fémorocutanée neuralgia (or m éralgie paresthetica) with dysesthesia of the outside leg and hypoesthesia “racket” on the same level;

– Neuralgia génitocrurale.

Sciatic not root:

By sciatic plexus injury (sacral plexus) are rare and usually secondary to pelvic neoplasm or local radiotherapy.

Sciatic nerve block are secondary to a tumor of the trunk of the sciatic nerve (schwannoma or neurinoma), truncal a compression in the buttock by a hematoma, abscess or muscle tumor, direct trauma to the nerve during a intramuscular injection, or a stretch in a hip dislocation context (or prosthesis).

Posterior sciatic cordonales are exceptional (tabes, multiple sclerosis).

Severity Diagnosis:

Sometimes sciatica requires urgent surgical intervention, preceded by a neuroradiology imaging.

Sciatica hyperalgic:

Sciatica hyperalgic defines a severe intensity pain, permanent insomniante not improved by bed rest, nonsteroidal anti-inflammatory drugs (NSAIDs), including intravenous infusion, and analgesics, including morphine.

Paralyzing sciatica:

Sciatica paralyzing (and not parésiante) is accompanied by a challenge cit below 3 engine and of one or more muscle groups depending on the relevant root.

Sometimes paralysis, complete or substantially complete, occurs immediately or very quickly, possibly coinciding with the disappearance of sciatic pain. This trend can be related to root lesion of ischemic type, very poor prognosis, even in case of rapid response.

Syndrome-tail horse:

The syndrome of the tail-to-horse (sometimes limited to a hemisyndrome) associates, the sciatic pain, different negative symptoms should know by track interview and physical examination:

– Urinary incontinence or rétentionnelles events;

– Anal sphincter incontinence with hypotonia;

– incapacity ;

– Hypoesthesia in the saddle.


Pain operating in a mechanical rhythm:

The occurrence of mechanical sciatica should suggest looking first and foremost a root of discogenic compression.

The responsibility of a herniated disc is indeed engaged in more than 90% of cases of sciatica.

Original sciatica disc:

Clinical arguments:

These arguments are found in the interrogation and physical examination:

– Youth (under 60 years);

– Exposed profession, sports activities; sudden or rapid onset after any triggering event;

– Repeated low back pain history;

– Impulsivity pain;

– Sciatica monoradicular;

– Deviation analgesic bayonet and / or blocking lumbar flexion;

– Sign direct root Lasègue and / or crossed;

– Preserved condition and apyrexia.

Eventually, plain radiographs are normal or mundane found degenerative signs and absence of inflammatory syndrome.

Iconographic arguments:

The neuroradiology imaging allows direct visualization (CT, MRI, or discography) or indirect (myelography) of the herniated disc. These reviews are of interest before completion of a surgery on a hernia in an emergency context or in the case of a rebel sciatica medical treatment.

* To scan :

The scanner, made without IV injection of iodine remains neuroradiological examination of choice in first intention. It allows to study the L3 / L4 discs, L4 / L5 and L5 / S1 (or the overlying discs express indication of the prescriber).

The herniated disc is visible as a posterior bulging disc in the spinal canal, sometimes median but more often lateralized, contacting a root of the sciatic nerve, it can suppress or cover.

A very lateral extent possible, foraminal or extraforaminal. Similarly, the herniated disc can migrate vertically behind the vertebral body or suspension underlying. Finally, in very large hernias, a fragment can detach and migrate away from the disc space that gave birth (excluding hernia).

The main drawback of the scanner is that it is performed in a recumbent patient can then ignore or underestimate herniated discs called “positional” appearing only sitting or standing (rare event).

* Magnetic resonance imaging:

MRI, which includes sagittal and transverse sections, suffering from the same complaint that the scanner (examination done coated). It sometimes allows the diagnosis of hernia unknown to the scanner. Most importantly, it allows more accurately assess the measurements of the lumbar canal and in the case of diagnostic uncertainty, allows to formally rule out other diseases (intraductal tumor, for example). Finally, it is the only feasible examination in exploration of sciatica during pregnancy (after 3 months).

* Radiculography:

Radiculography (or lumbar myelography) corresponds to the opacification of the dural sheath and root sheaths from such animals by injection into the cerebrospinal fluid of an iodinated product. Unlike MRI and scanner, it enables the implementation of dynamic views in a sitting and standing position. It also can search a herniated disc and specify the canal measurements in scoliosis patients as well as patients who underwent lumbar instrumented arthrodesis (CT artifacts and MRI). Finally, it allows a cytological and biochemical study of cerebrospinal fluid taken early in the exam.The visualization of the herniated disc is indirect, it being suspected that its consequences: repression or amputation of a root sheath, delivery of the dural sheath.

The disadvantages of this procedure are numerous: invasive examination, exposing the risks of infection, allergy to iodine and lumbar postponction syndrome, non-visualization of very lateral hernia and foraminal extraforaminal.

* Discography:

Discography, possibly coupled to the scanner (disco-scanner), has not much guidance since abandoning Chemonucleolysis.

Clinical forms:

Surgical emergencies are relatively rare: hyperalgesia sciatica, sciatica and paralyzing syndrome-tail horse. A scanner is required before surgery.

Sciatica biradiculaire (L5 and S1 on the same side) can be linked to a large median hernia L5 / S1 (compression S1 to its emergence), with lateral extension (L5 compression in its passage through the foramen L5 / S1). Sciatica (L5 or S1) bilateral or rocking may be related with a large median hernia, compressing the two roots to their emergence.

The exclusion of a herniated disc can be suspected clinically before disappearance of back pain coinciding with a sharp increase in sciatic pain and the possible appearance of a challenge cit engine. This phenomenon of exclusion may also correspond to a spontaneous recovery mode.

Finally, sciatica recurrence is always possible in a subject that has already undergone surgical discectomy. It may be then a hernia on another floor or recurrent hernia surgery in stage (3% of cases). In the latter case, the confirmation of recurrence based on the realization of a CT and / or MRI, without then with intravenous injection of a contrast agent (iodine for computed tomography and magnetic contrast agent for the MRI), to distinguish postoperative epidural fibrosis, which “takes the contrast” (as vascularized), a genuine disc recurrence, which does not take it.

Other etiologies “mechanical”:

It is essentially degenerative pathologies of facet joint origin, willingly associated with discarthrosiques changes.

The facet joint origin symptomatology is characterized mainly by: the field: patient beyond 50 years, often hyperlordotique;

– The concept of chronic low back pain progressively worsening, with pain in bar or frankly lateralized, increased by prolonged sitting and trampling;

– The existence of referred pain (buttocks, trochanteric region, groin, back of thighs).

The existence of a genuine radicular sciatica in this context is much rarer and not unequivocal mechanism. It differs from the sciatica by:

– Its very gradual and occurred without triggering factor;

– Its very mechanical and not impulsive; the possible association with neurogenic claudication device, reminiscent of lumbar spinal stenosis;

– Lack of Lasegue (lumbar or radicular) and segmental stiffness of the spine.

Plain radiographs gladly reveal signs of facet joint osteoarthritis: hypertrophy and condensation facet joints, pinching or loss of the joint space interfacettaire. Degenerative spondylolisthesis, usually anterolisthesis type of L4 on L5, it often associates, as well as signs of degenerative disc disease or signs of instability in the anteroposterior and lateral plane.If a scanner is made in this context because, for example, a rebel sciatic medical treatment, it may possibly be:

– Joint original posterior osteophytes and / or rétrocorporéale, the development of root canal can be pathogenic to a nerve root;

– A synovial cyst developed from a facet joint articulation, sometimes responsible for a root compression in the corresponding foramen;

– Especially an acquired narrowing of the spinal canal, often of mixed origin, slipped (staggered protrusions) and facet joint osteoarthritis, suspected on clinical (peripheral neurogenic claudication) and confirmed by CT, MRI or at best lumbar myelography (made referred mostly preoperative).

In this context, a degenerative spondylolisthesis is often observed and increases the ductal stricture;

– Finally, we must mention the spondylolisthesis “congenital” L5 on SI, complicating mostly bilateral spondylolysis of L5, easily highlighted on the oblique impacts. Spondylolisthesis is probably congenital but readily increased by some sports with repeated efforts in lordosis (classical dance), or trauma. It may be asymptomatic or, conversely, cause chronic low back pain, sometimes supplemented with sciatica, the mechanism is not unique (disc herniation associated foraminal narrowing, fibrous nodule at the site of spondylolysis, etc. .).

Inflammatory pain evolving on pace:

Besides the inflammatory pace of sciatic pain, there is often more suggestive arguments sciatica “symptomatic” or “secondary”

– The field: elderly patient neoplastic potential antecedent notion of impaired general condition ± fever;

– The absence of triggering circumstance and progressive worsening;

– The character eventually pluriradiculaire (stepped and / or bilateral) of neurological involvement;

– The existence of an inflammatory syndrome;

– The existence of suspicious radiological lesions.

These symptoms call for further explorations and asking, in particular, a bone scan and especially MRI of the lumbar spine. This can then be:

– Spondylodiscitis;

– A malignant bone tumor pathology (cf. spinal pain).

Other conditions can cause pain lomboradiculaires inflammatory pace:

– Spondyloarthritis;

– The meningoradiculitis, the first of which Lyme disease, whose evocation involves performing a lumbar puncture, in search of an increase in CSF protein and lymphocytosis, and serology (blood and cerebrospinal fluid ).


Sciatica disc:


Medical treatment:

The rest is needed in acute period, but its duration should be as short as possible, and strict bed rest, once strongly advocated, is now deprecated.

* General Drug Treatments:

Analgesics are usually level I or II (WHO classifi cation). Exceptionally (sciatica hyperalgesia), level III analgesics (morphine) may be necessary.

NSAIDs are usually prescribed orally. For the record, intramuscular administration, known more rapidly effective than the oral route, does bring in a modest gain at the cost of possible complications (hematoma, abscess). In contrast, intravenous administration (ketoprofen), usually in hospital, is interesting in very acute sciatica.

Oral corticosteroids, started usually at a dose of 1 mg / kg / day and then gradually reduced over a fortnight, may be proposed if ineffi effectiveness of NSAIDs.

Muscle relaxants (Myolastan®, Panos®, Valium) are interesting as much for their decontracturing properties for their sedative properties and should therefore be prescribed at night. In this context, the Rivotril®, which is an anticonvulsant, is also readily prescribed. Other muscle relaxants, sedatives less, can be administered during the day (Miorel®, Coltramyl®).

* Local Drug Treatments:

These are the epidural, which can be made in consultation or hospitalization.

Most often they are practiced by interspinous route, but can also be made by the first sacral foramen or sacrococcygeal hiatus. In all cases, the aseptic precautions must be drastic. The most commonly used product is the Hydrocortancyl® 125 mg. Infiltration, the number of 1 to 3 are performed every few days.

The intrathecal infiltration (Luccherini) requires a hospital stay of 24 hours. This technique is not widely used because of the risk of post-dural-puncture headache, and especially cerebral thrombophlebitis rare but extremely serious or even fatal.

* Physical treatments and dietary measures:

An orthosis can be recommended, often in conjunction with a infiltrative treatment.

It consists of the preparation, the patient himself, a removable lombostat (Velcro closure) resin or other thermoformable material, kept a month on average.

Quitting lombostat can be relayed by a more flexible lumbar support belt.

Physiotherapy in a double interest. In the acute phase, it is only sedative and relaxant (massages, physiotherapy, parafango).

Distance to the acute phase (usually after a period of at least three weeks), it rather proprioceptive vocation, with strengthening the midsection, sub-pelvic relaxation and learning lumbar locking techniques. The term rehabilitation is then taken literally, it up to the patient’s participation in the lessons taught by “back schools”.

Whatever support type, rehabilitation should ideally include advice concerning the professional life (change of means of transport, crowding heavy loads uprisings, adaptation of the workplace or outplacement) and leisure life (stop harmful sports, change to the technical gesture, gymnastics advice and alternative sports activities).

In this context, finally, weight reduction should always be recommended.

The elongation of vertebral table are practically abandoned. Finally, spinal manipulation and osteopathic techniques were “theoretically” no place in the treatment of sciatica original disc, running the risk of a sudden worsening symptoms (excluding hernia).

The debate on these techniques is inexhaustible.

Non-medical treatments:

This is the surgical pathological disc, sciatica reserved for rebels to at least 6 weeks of medical treatment or properly led to complicated sciatica.

It must be, in any case, preceded by a neuroradiological exploration to confirm the herniated disc and the reality of the nerve root.

Most importantly, the removal of the herniated disc and disc it came from should apply to cases of true sciatica, and not to patients with low back pain without associated disc nerve root compression. While it is often very effective on the sciatic pain, it is little or no on lower back pain, even being rather purveyor of chronic low back pain of facet joint origin.

Surgery is indicated in emergency in case of complicated sciatica (sciatic paralyzing syndrome-tail horse) or with a delay, in case of sciatica resistant to medical treatment. It always is, whatever the technique, excision of the hernia, complete with a disc curettage as complete as possible (discectomy), to limit the risk of recurrence.

The gesture is performed under general anesthesia or epidural anesthesia. It is effective in 90% of cases, the price of a low morbidity (spondylitis, wounds dura mériennes, postoperative motor deficits, etc.). Postoperative epidural fibrosis is commonplace and probably non-pathogenic.

Finally, the main complication of surgery is chronic low back pain of facet joint origin, related to disc space narrowing.

In this context, some techniques “preventive” of postoperative back pain are being evaluated (interbody cages).


In case of complicated sciatica, surgical discectomy is an undeniable urgency,

If sciatica uncomplicated discogenic, treatment should be primarily medical: First of drug (NSAID and corticosteroids) and infiltrative, outpatient or inpatient. In 80% of cases, this support allows the healing sciatica within 1 to 2 months.The initiation of a proprioceptive rehabilitation away from the acute episode part in preventing recurrence.

In 20% of cases, sciatica is refractory to medical treatment, yet properly conducted and duration suffi cient, requiring resort to surgery.

Sciatica herniated not mechanical:

If symptomatic narrowing of the spinal canal, concerning mostly elderly patients, treatment should be as long as medical possible, that is to say, medicated, infiltrative (interest intradural infiltrations) and physiotherapy (rehabilitation focusing on postures in delordosis). If unsuccessful, with gradual reduction in the walking, decompressive laminectomy one to be discussed. A spinal fusion may be needed in case of degenerative spondylolisthesis of L4 on L5.