Full endoscopic versus open discectomy for sciatica: randomised controlled non-inferiority trial.

OBJECTIVE: To assess whether percutaneous transforaminal endoscopic discectomy (PTED) is non-inferior to conventional open microdiscectomy in reduction of leg pain caused by lumbar disc herniation. DESIGN: Multicentre randomised controlled trial with non-inferiority design. SETTING: Four hospitals in the Netherlands. PARTICIPANTS: 613 patients aged 18-70 years with at least six weeks of radiating leg pain caused by lumbar disc herniation. The trial included a predetermined set of 125 patients receiving PTED who were the learning curve cases performed by surgeons who did not do PTED before the trial. INTERVENTIONS: PTED (n=179) compared with open microdiscectomy (n=309). MAIN OUTCOME MEASURES: The primary outcome was self-reported leg pain measured by a 0-100 visual analogue scale at 12 months, assuming a non-inferiority margin of 5.0. Secondary outcomes included complications, reoperations, self-reported functional status as measured with the Oswestry Disability Index, visual analogue scale for back pain, health related quality of life, and self-perceived recovery. Outcomes were measured until one year after surgery and were longitudinally analysed according to the intention-to-treat principle. Patients belonging to the PTED learning curve were omitted from the primary analyses. RESULTS: At 12 months, patients who were randomised to PTED had a statistically significantly lower visual analogue scale score for leg pain (median 7.0, interquartile range 1.0-30.0) compared with patients randomised to open microdiscectomy (16.0, 2.0-53.5) (between group difference of 7.1, 95% confidence interval 2.8 to 11.3). Blood loss was less, length of hospital admission was shorter, and timing of postoperative mobilisation was earlier in the PTED group than in the open microdiscectomy group. Secondary patient reported outcomes such as the Oswestry Disability Index, visual analogue scale for back pain, health related quality of life, and self-perceived recovery, were similarly in favour of PTED. Within one year, nine (5%) in the PTED group compared with 14 (6%) in the open microdiscectomy group had repeated surgery. Per protocol analysis and sensitivity analyses including the patients of the learning curve resulted in similar outcomes to the primary analysis. CONCLUSIONS: PTED was non-inferior to open microdiscectomy in reduction of leg pain. PTED resulted in more favourable results for self-reported leg pain, back pain, functional status, quality of life, and recovery. These differences, however, were small and may not reach clinical relevance. PTED can be considered as an effective alternative to open microdiscectomy in treating sciatica. TRIAL REGISTRATION: NCT02602093ClinicalTrials.gov NCT02602093.

Effects of a water extract of Lepidium meyenii root in different models of persistent pain in rats.

Lepidium meyenii (Walp.), commonly called maca, is an Andean crop belonging to the Brassicaceae family. Maca hypocotils are habitually consumed as customary food as well as traditional remedies for pathological conditions such as infertility. Moreover, the characterization of maca extracts revealed the presence of compounds that are able to modulate the nervous system. Aimed to evaluate the efficacy of L. meyenii in persistent pain, the present study analyzed the effects of a commercial root extract from maca in different animal models reproducing the most common causes of chronic painful pathologies. A qualitative characterization of this commercial extract by high performance liquid chromatography-mass spectrometry and tandem mass spectrometry analyses allowed us to confirm the presence of some macamides known as bioactive constituents of this root and the absence of the main aromatic glucosinolates. The acute oral administration of maca extract is able to reduce mechanical hypersensitivity and postural unbalance induced by the intra-articular injection of monoiodoacetate and the chronic-constriction injury of the sciatic nerve. Furthermore, L. meyenii extract reverts pain threshold alterations evoked by oxaliplatin and paclitaxel. A good safety profile in mice and rats was shown. In conclusion, the present maca extract could be considered as a therapeutic opportunity to relieve articular and neuropathic pain.

Modified Percutaneous Lumbar Foraminoplasty and Percutaneous Endoscopic Lumbar Discectomy: Instrument Design, Technique Notes, and 5 Years Follow-up.

BACKGROUND: Conventional percutaneous endoscopic lumbar discectomy (PELD) with an "inside-outside" technique has 4.3% - 10.3% surgical failure rate, especially in central herniated discs (HDs), migrated HDs, and axillary type HDs. PELD with foraminoplasty has been used for complex HDs. Percutaneous lumbar foraminoplasty (PLF), which is performed with a trephine or bone reamer introduced over a guidewire without a protective working cannula in the original Tessys technique, can quickly cut the hypertrophied bony structure under fluoroscopic guidance, and risk injury to the exiting and traversing nerve roots. STUDY DESIGN: A prospective cohort study. SETTING: Hospital and outpatient surgical center. OBJECTIVE: To evaluate the outcome and safety of modified PLF-PELD with a specially designed instrument for complex uncontained lumbar HDs. METHOD: From April of 2007 to April of 2009, 148 patients with uncontained lumbar HDs were treated with modified PLF-PELD. Magnetic resonance imaging (MRI) checkup was performed the next morning after the operation. Outcomes of symptoms were evaluated by follow-up interviews at 3 months, 6 months, one year, and 5 years after surgery. Low back pain and leg pain were measured by visual analog scale (VAS) score (1 - 100). Functional outcomes were assessed by using the Oswestry Disability Index (ODI) and modified MacNab criteria. RESULTS: Follow-up data were obtained from 134 cases, including 14 cases on L3-4, 78 cases on L4-5, and 42 cases on L5-S1. One hundred-eight cases were prolapse type, while 26 cases were sequestration type. Pre-operative symptoms and deficits included nerve root dermatome hypoesthesia in 98 patients (73%), nerve root myotome muscle weakness in 32 patients (23%), and weakening or disappearance of tendon reflex in 43 patients (32%). No case required conversion to an open procedure during the surgery. Low back pain and leg pain were significantly relieved immediately after surgery in all patients. MRI examination showed adequate removal of HD in all patients. VAS scores and ODI values were significantly lower at all time points after surgery than before surgery. The percentage of pain relief in leg pain was significantly higher than that in low back pain (P < 0.01). But there was no significant correlation between duration of the preoperative symptoms and the percentage of pain relief. MacNab scores at 5 years after surgery were obtained from 134 patients. Seventy-five cases were rated "excellent"; 49 were rated "good," Five patients experienced heavier low back pain, thus being classified as "fair." Five cases with recurrence were rated "poor." Preoperative and postoperative (5 years follow-up) related nerve root function status was compared. Sensation and muscle strength recovered significantly (P < 0.01), while tendon reflex was not changed (P = 0.782). No patients had infections. Five patients were complicated with dysesthesia in distribution of the exiting nerve that was all operated at L5-S1. Complaints were reduced one week after treatment with medium frequency pulse electrotherapy. Five cases required a revision surgery after recurrence. LIMITATIONS: This is an observational clinical case series study without comparison. CONCLUSION: Modified PLF-PELD with a specially designed instrument is a less invasive, effective and safe surgery for complex uncontained lumbar DH.Key words: Lumbar disc herniation, minimally invasive treatment, foraminoplasty, percutaneous endoscopic lumbar discectomy.

[Sciatica. From stretch rack to microdiscectomy]. / Ischias. Von der Streckbank zur Mikrodiskektomie.

In ancient times as well as in the Middle Ages treatment options for discogenic nerve compression syndrome were limited and usually not very specific because of low anatomical and pathophysiological knowledge. The stretch rack (scamnum Hippocratis) was particularly prominent but was widely used as a therapeutic device for very different spinal disorders. Since the beginning of the nineteenth century anatomical knowledge increased and the advances in the fields of asepsis, anesthesia and surgery resulted in an increase in surgical interventions on the spine. In 1908 the first successful lumbar discectomy was initiated and performed by the German neurologist Heinrich O. Oppenheim (1858-1919) and the surgeon Fedor Krause (1857-1937); however, neither recognized the true pathological condition of discogenic nerve compression syndrome. With the landmark report in the New England Journal of Medicine in 1934, the two American surgeons William Jason Mixter (1880-1958) and Joseph Seaton Barr (1901-1963) finally clarified the pathomechanism of lumbar disc herniation and furthermore, propagated discectomy as the standard therapy. Since then interventions on intervertebral discs rapidly increased and the treatment options for lumbar disc surgery quickly evolved. The surgical procedures changed over time and were continuously being refined. In the late 1960s the surgical microscope was introduced for spinal surgery by the work of the famous neurosurgeon Mahmut Gazi Yasargil and his colleague Wolfhard Caspar and so-called microdiscectomy was introduced. Besides open discectomy other interventional techniques were developed to overcome the side effects of surgical procedures. In 1964 the American orthopedic surgeon Lyman Smith (1912-1991) introduced chemonucleolysis, a minimally invasive technique consisting only of a cannula and the proteolytic enzyme chymopapain, which is injected into the disc compartment to dissolve the displaced disc material. In 1975 the Japanese orthopedic surgeon Sadahisa Hijikata described percutaneous discectomy for the first time, which was a further minimally invasive surgical technique. Further variants of minimally invasive surgical procedures, such as percutaneous laser discectomy in 1986 and percutaneous endoscopic microdiscectomy in 1997, were also introduced; however, open discectomy, especially microdiscectomy remains the therapeutic gold standard for lumbar disc herniation.

Trigger point-related sympathetic nerve activity in chronic sciatic leg pain: a case study.

Sciatica has classically been associated with irritation of the sciatic nerve by the vertebral disc and consequent inflammation. Some authors suggest that active trigger points in the gluteus minimus muscle can refer pain in similar way to sciatica. Trigger point diagnosis is based on Travel and Simons criteria, but referred pain and twitch response are significant confirmatory signs of the diagnostic criteria. Although vasoconstriction in the area of a latent trigger point has been demonstrated, the vasomotor reaction of active trigger points has not been examined. We report the case of a 22-year-old Caucasian European man who presented with a 3-year history of chronic sciatic-type leg pain. In the third year of symptoms, coexistent myofascial pain syndrome was diagnosed. Acupuncture needle stimulation of active trigger points under infrared thermovisual camera showed a sudden short-term vasodilatation (an autonomic phenomenon) in the area of referred pain. The vasodilatation spread from 0.2 to 171.9 cm(2) and then gradually decreased. After needling, increases in average and maximum skin temperature were seen as follows: for the thigh, changes were +2.6°C (average) and +3.6°C (maximum); for the calf, changes were +0.9°C (average) and +1.4°C (maximum). It is not yet known whether the vasodilatation observed was evoked exclusively by dry needling of active trigger points. The complex condition of the patient suggests that other variables might have influenced the infrared thermovision camera results. We suggest that it is important to check if vasodilatation in the area of referred pain occurs in all patients with active trigger points.

Evaluation of the analgesic effect of dextromethorphan and its interaction with nitric oxide on sciatic nerve ligated rats.

The symptoms of neuropathic pain are often intractable because they are poorly relieved by conventional analgesics. This therapeutic area remains one of the least satisfactorily managed by current drugs. Effective therapy for this type of pain is lacking, and the underlying mechanisms are poorly understood. The present study was undertaken to determine the effect of sciatic nerve ligation on inducing neuropathic pain and to understand the mechanisms involved, and the effect of, an L-nitro-arginine methyl ester (L-NAME)/dextromethorphan combination therapy on reducing neuropathic pain. According to our results, L-NAME and dextromethorphan showed analgesic properties, but only 100 mg/kg L-NAME had an additive effect on the analgesic effects of dextromethorphan. Our observations support the idea that N-methyl-D-aspartate/nitric oxide pathways play an important role in the development of such sciatic nerve ligated-evoked pathological pain conditions, thus this combination therapy could be used instead of conventional treatment.

[Patient satisfaction with spinal cord stimulation for failed back surgery syndrome]. / Satisfacción del paciente con síndrome de dolor de raquis postquirúrgico portador de un sistema de neuroestimulación medular.

INTRODUCTION: The incidence of failed back surgery syndrome is about 40%. We studied the efficacy of and patient satisfaction with use of a spinal cord stimulator to treat this syndrome. MATERIAL AND METHODS: A period of 72 months of experience with implanted spinal cord stimulators was analyzed in this observational, descriptive study of patients who were included retrospectively. Patients met criteria for failed back surgery syndrome according to the taxonomy of the International Association for the Study of Pain. A chi2 test was used to compare qualitative variables. Results for quantitative variables were compared by analysis of variance. Statistical significance was set at P < 0.05. RESULTS: Thirty-four patients were studied. Both lumbar back and radicular pain assessed on a visual analog scale (VAS) decreased significantly from the mean overall score of 6. As time passed, fewer patients felt the system met their expectations. More patients said the system met their expectations in the first months after implantation (73.5%) than at a later interview (55.9%). Seventeen complications were reported, the most common being mechanical difficulties with the implanted stimulator. None of the complications were serious. Use of additional medication to control pain decreased in 38.2% of the cases. A total of 73.5% of the patients considered the implanted stimulator to be beneficial and 67.6% would have a spinal cord stimulator implanted again. CONCLUSIONS: Spinal cord stimulation improves lumbar back pain in patients with failed back surgery syndrome and reduces the amount of additional medication taken to control pain. It is important for patients to adjust their expectations about the implanted stimulator.

Satisfacción del paciente con síndrome de dolor de raquis postquirúrgico portador de un sistema de neuroestimulación medular / Patient satisfaction with spinal cord stimulation for failed back surgery syndrome

INTRODUCCIÓN: El síndrome de dolor de raquis postquirúrgico (SDRPQ) presenta una incidencia de hasta un 40% tras cirugía lumbosacra. Estudiamos la eficacia y satisfacción de los pacientes portadores de un sistema de neuroestimulación de la médula espinal. MATERIAL Y MÉTODO: Estudio observacional, retrospectivo, descriptivo de 72 meses de duración en pacientes portadores de un neuroestimulador medular con criterios de taxonomía descritos por la IASP para SDRPQ. Estudio estadístico Chi cuadrado para variables cualitativas y ANOVA para las cuantitativas. Significativos valores de p < 0,05. RESULTADOS: Se incluyeron 34 pacientes. Encontramos una disminución significativa del dolor en la EVA tanto para la lumbalgia como para el dolor radicular (EVAglobal con una media de 6). Encontramos una disminución en el ajuste de las expectativas respecto al sistema al transcurrir el tiempo. Un porcentaje superior de pacientes expresan ajuste adecuado a sus expectativas, 73,5% en los primeros meses del implante y 55,9% al momento de la entrevista respectivamente. Se recogieron un total de 17 complicaciones, ninguna grave, siendo las más frecuentes las mecánicas relacionadas con el sistema implantado. La medicación coadyuvante para controlar el dolor disminuyó en un 38,2% de los casos. El 73,5% de los pacientes encontró beneficioso el sistema implantado y el 67,6% se implantaría nuevamente otro sistema de neuroestimulación medular. CONCLUSIONES: La neuroestimulación medular proporciona mejoría al dolor lumbar en pacientes con SDRPQ y disminuye la ingesta de medicación coadyuvante para controlar el dolor. Es importante ajustar las expectativas del paciente ante el sistema implantado

INTRODUCTION: The incidence of failed back surgery syndrome is about 40%. We studied the efficacy of and patient satisfaction with use of a spinal cord stimulator to treat this syndrome. MATERIAL AND METHODS: A period of 72 months of experience with implanted spinal cord stimulators was analyzed in this observational, descriptive study of patients who were included retrospectively. Patients met criteria for failed back surgery syndrome according to the taxonomy of the International Association for the Study of Pain. A X2 test was used to compare qualitative variables. Results for quantitative variables were compared by analysis of variance. Statistical significance was set at P<0.05. RESULTS: Thirty-four patients were studied. Both lumbar back and radicular pain assessed on a visual analog scale (VAS) decreased significantly from the mean overall score of 6. As time passed, fewer patients felt the system met their expectations. More patients said the system met their expectations in the first months after implantation (73.5%) than at a later interview (55.9%). Seventeen complications were reported, the most common being mechanical difficulties with the implanted stimulator. None of the complications were serious. Use of additional medication to control pain decreased in 38.2% of the cases. A total of 73.5% of the patients considered the implanted stimulator to be beneficial and 67.6% would have a spinal cord stimulator implanted again. CONCLUSIONS: Spinal cord stimulation improves lumbar back pain in patients with failed back surgery syndrome and reduces the amount of additional medication taken to control pain. It is important for patients to adjust their expectations about the implanted stimulator

Arthroscopic release of the piriformis muscle under local anesthesia for piriformis syndrome.

We developed a minimally invasive technique of releasing the piriformis muscle under endoscopic control for entrapment neuropathy of the sciatic nerve because of tension and contraction of the piriformis muscle. This surgical technique was performed in patients who fulfilled at least 5 of 9 diagnostic criteria we established and who did not respond to conservative therapy for 6 months or more. Although a cavity was maintained using a disposable syringe (10 mL) with a cut tip, an arthroscope (4 mm in diameter) was inserted at an oblique viewing angle of 30 degrees, and the muscle was identified. The area from the musculotendinous junction to the muscle was gradually incised using a special scraper. In particular, pain disappeared simultaneously with release of the piriformis muscle during surgery. With this technique, an adequate cavity can be produced and maintained in a manner similar to that in posterior endoscopic surgery for intervertebral disc herniation. This technique is useful for reducing postoperative pain and allows early return to activity.

Sciatica and the lumbar disk syndrome: a historic perspective.

The dynamics of the human spine mark the lumbar disk syndrome and accompanying sciatic complaints as long-standing afflictions of our species. Although Greco-Roman erudition suitably described the ailment, uneven diagnostic and therapeutic acumen confused inquiry for many centuries. Only with the 19th Century advent of improved clinical facilities, pathologic correlation, and active surgical exploration did real insight commence. Not, however, until the 1934 landmark publication of Mixter and Barr was the herniated lumbar disk indicated as a major cause of sciatica. Despite such advances, numerous unresolved issues still surround this disease.