Pain Generators of the Lumbar Spine

In vivo measurement of intradiscal pressure changes related to thrust and non-thrust spinal manipulation in an animal model: a pilot study

BACKGROUND

The intervertebral disc is a known back pain generator and is frequently the focus of spinal manipulative therapy evaluation and treatment. The majority of our current knowledge regarding intradiscal pressure (IDP) changes related to spinal manual therapy involves cadaveric studies with their inherent limitations. Additional in vivo animal models are needed to investigate intervertebral disc physiological and molecular mechanisms related to spinal manipulation and spinal mobilization treatment for low back disorders.

METHODS

Miniature pressure catheters (Millar SPR-1000) were inserted into either the L4-L5 or L5-L6 intervertebral disc of 3 deeply anesthetized adult cats (Oct 2012-May 2013). Changes in IDP were recorded during delivery of instrument-assisted spinal manipulation (Activator V® and Pulstar®) and motorized spinal flexion with/without manual spinous process contact.

RESULTS

Motorized flexion of 30° without spinous contact decreased IDP of the L4-L5 disc by ~ 2.9 kPa, while physical contact of the L4 spinous process decreased IDP an additional ~ 1.4 kPa. Motorized flexion of 25° with L5 physical contact in a separate animal decreased IDP of the L5-L6 disc by ~ 1.0 kPa. Pulstar® impulses (setting 1-3) increased IDP of L4-L5 and L5-L6 intervertebral discs by ~ 2.5 to 3.0 kPa. Activator V® (setting 1-4) impulses increased L4-L5 IDP to a similar degree. Net changes in IDP amplitudes remained fairly consistent across settings on both devices regardless of device setting suggesting that viscoelastic properties of in vivo spinal tissues greatly dampen superficially applied manipulative forces prior to reaching deep back structures such as the intervertebral disc.

CONCLUSIONS

This study marks the first time that feline in vivo changes in IDP have been reported using clinically available instrument-assisted spinal manipulation devices and/or spinal mobilization procedures. The results of this pilot study indicate that a feline model can be used to investigate IDP changes related to spinal manual therapy mechanisms as well as the diminution of these spinal manipulative forces due to viscoelastic properties of the surrounding spinal tissues. Additional investigation of IDP changes is warranted in this and/or other in vivo animal models to provide better insights into the physiological effects and mechanisms of spinal manual therapy at the intervertebral disc level.

Oxygen-Ozone Therapy Associated with Alpha Lipoic Acid Plus Palmitoylethanolamide and Myrrh versus Ozone Therapy in the Combined Treatment of Sciatic Pain Due to Herniated Discs: Observational Study on 318 Patients

BACKGROUND

The aim of our observational study is to compare the therapeutic efficacy of combined treatment of oxygen-ozone therapy and oral treatment with alpha-lipoic acid (ALA) + palmitoylethanolamide (PEA) and myrrh in patients with peripheral neuropathic pain (sciatica) on radicular disc conflict from disc herniation and the results obtained with oxygen-ozone treatment alone.

METHODS

We enrolled 318 patients with the neuroradiological diagnosis of disc herniation performed with computed tomography (CT) or magnetic resonance imaging (MRI) and symptoms characterized by low back pain complicated by sciatica, which we divided into two groups. Group A was composed of 165 patients who were treated only with oxygen-ozone therapy with CT-guided intraforaminal technique, while the remaining 153 (Group B) have undergone combined oral treatment with ALA + PEA and myrrh. Follow-up visits for the evaluation of the clinical outcome of the treatment were conducted after 60 ± 8 days using a modified version of McNab's method.

RESULTS

At the clinical check-up, 126/165 patients included in Group A had a complete remission of pain (76.4%), while in Group B, 119/153 (77.8%) had a complete remission of pain.

CONCLUSION

The results highlight how the treatment associated with ozone therapy and oral administration of alpha-lipoic acid + palmitoylethanolamide and myrrh is preferred over the simple treatment with only ozone in such patients in the phase of greatest acuity of the disease, where the pain appears to be better controlled.

Effect of time of day on height loss response variability in asymptomatic participants on two consecutive days

Ergonomists measure height loss in relation to loads imposed on the spine. It is difficult to interpret whether height loss responses recorded on different days are accurate due to natural daily fluctuations in height loss and measurement variability. The objective of this research was to investigate whether the variability of height loss in the sitting position is affected by time of day and to analyse day-to-day variability in asymptomatic participants. Fifty asymptomatic participants attended two sessions (morning and afternoon) of stadiometry testing on four separate days. The results showed that a variability of height loss response changes in excess of 0.886 mm in morning and 1.128 mm in afternoon between days indicates that an intervention itself has influenced height loss. Future investigations on height loss in sitting should take these results into consideration to confidently state that an intervention has influenced height loss response at each time of day. Practitioner summary: Daily fluctuation creates difficulties when interpreting whether height losses recorded on different days and times are intervention related. Seated stadiometry measures on different days and times of day demonstrated specific levels of natural variation. Changes above 0.886 mm (morning) and 1.128 mm (afternoon) can be attributed to intervention effects. Abbreviations: LBP: low back pain; SEM: standard error of measurement; MeanSDs: means of standard deviations.

Changes in Spinal Height After Manual Axial Traction or Side Lying: A Clinical Measure of Intervertebral Disc Hydration Using Stadiometry

OBJECTIVES

The purpose of this study was to determine the immediate effects of a manual therapy technique consisting of axial traction compared with side lying on increased spine height after sustained loading.

METHODS

Twenty-one asymptomatic participants were included. Participants either received manual therapy technique consisting of manual axial traction force for 2 consecutive rounds of 3 minutes or sustained side lying for 10 minutes. Spine height was measured using a commercially available stadiometer. Spinal height change was determined from measurements taken after loaded walking and measurements taken after manual therapy. A paired t test was performed to determine if a manual therapy technique consisting of axial traction increased spinal height after a period of spinal loading.

RESULTS

A significant increase in height was found after both manual therapy technique and sustained side lying (P < .0001). The mean height gain was 8.60 mm using 3-dimensional axial separation.

CONCLUSION

This study is an initial attempt at evaluating the biomechanical effects of manual therapy technique consisting of axial traction. Both manual axial traction force and sustained side-lying position were equally effective for short-term change in spine height after a loaded walking protocol among healthy asymptomatic individuals. This study protocol may help to inform future studies that evaluate spine height after loading.

Promise, progress, and problems in whole disc tissue engineering

Intervertebral disc degeneration is frequently implicated as a cause of back and neck pain, which are pervasive musculoskeletal complaints in modern society. For the treatment of end stage disc degeneration, replacement of the disc with a viable, tissue-engineered construct that mimics native disc structure and function is a promising alternative to fusion or mechanical arthroplasty techniques. Substantial progress has been made in the field of whole disc tissue engineering over the past decade, with a variety of innovative designs characterized both in vitro and in vivo in animal models. However, significant barriers to clinical translation remain, including construct size, cell source, culture technique, and the identification of appropriate animal models for preclinical evaluation. Here we review the clinical need for disc tissue engineering, the current state of the field, and the outstanding challenges that will need to be addressed by future work in this area.

Interaoperative use of epidural methylprednisolone or bupivacaine for postsurgical lumbar discectomy pain relief: a randomized, placebo-controlled trial

BACKGROUND

Many patients with lumbar disc surgery experience postoperative back and radicular pain, delaying hospital discharge and resumption of normal activity. Some surgeons have used intraoperative epidural corticosteroids and local anesthetics to decrease pain following surgery for a herniated lumbar disc. Controversies still exist regarding the benefits of these drugs. The present study was meant to compare the effects of the intraoperative administration of epidural methylprednisolone and bupivacaine with that of normal saline (placebo) in lumbar disc surgery for postoperative pain control.

PATIENTS AND METHODS

One hundred fifty patients with single level herniated nucleus pulposus (L4-L5 or L5-S1), which was refractory to 6 weeks of conservative management, were divided randomly in three groups. A standard hemipartial lamimectomy and discectomy was performed on all patients. At the end of the surgery, before the closure of fascia, 40 mg methylprednisolone with 3 mL normal saline for group 1, 2 mL bupivacaine 5% with 2 mL normal saline for group 2 and 4 mL normal saline for group 3 were instilled onto the epidural and exposed nerve root. Postoperative back and radicular pain intensity was assessed by a visual analogue scale (VAS) before and at 24, 48, 72, and 96 hours after surgery.

RESULTS

There was no significant difference in back and radicular pain intensity between the three groups.

CONCLUSION

Intraoperative administration of epidural methylprednisolone or bupivacaine does not relieve postoperative back and radicular pain.

Cervical interlaminar epidural steroid injection for neck pain and cervical radiculopathy: effect and prognostic factors

OBJECTIVE

To verify the usefulness of a fluoroscopy guided cervical interlaminar epidural steroid injection (CIESI) in patients with neck pain and cervical radiculopathy and to evaluate outcome predictors.

DESIGN

We retrospectively analyzed 91 patients from July 2004 to June 2005 in whom CIESI was initially performed for neck pain and cervical radiculopathy. Therapeutic effects were evaluated 2 weeks after the administration of CIESI, and CIESI effectiveness was graded using a five-point scale, namely, whether the pain had disappeared, was much improved, slightly improved, the same, or aggravated. We also used a visual analog scale (VAS) for the clinical evaluation. According to documentation and follow-up charts, we categorized treatments as effective or ineffective. Possible outcome predictors, namely, diagnosis (spinal stenosis vs herniated disc), primary symptoms (neck pain vs radiculopathy vs both), age, gender, and duration of pain (more or less than 6 months) were also analyzed. Fisher's exact test, the chi-square test, and multiple logistic regression analysis were used for the statistical analysis.

PATIENTS

After their medical records had been reviewed, 76 patients were included in this study. Inclusion criteria were: the availability of a cross-sectional image, such as a CT scan or an MR image, and a follow-up record after injection.

RESULTS AND CONCLUSIONS

The medical records of 76 patients (male:female = 41 : 35) of mean age 53.1 years (range 32 years to 82 years) were reviewed. Two weeks after injection, 55 patients (72.4%) had experienced effective pain relief. Patients with herniated discs had significantly better results than patients with spinal stenosis (86.1% vs 60.0%) (P < 0.05). Other non-significant predictors of an improved outcome included: a symptom duration of <6 months, a young age, and the presence of cervical radiculopathy. Multiple regression analysis showed that the only factor that was significantly associated with outcome was the cause of the pain, i.e., herniated disc or spinal stenosis. Fluoroscopy guided CIESI is a safe and effective means of treating patients with neck pain and cervical radiculopathy. The most important outcome predictor was cause of pain, and patients with herniated disc experienced better pain relief than those with spinal stenosis.