Innovative treatments for back pain

Radiation of pain: psychophysical evidence for a population coding mechanism in humans

ABSTRACT

The spread of pain across body locations remains poorly understood but may provide important insights into the encoding of sensory features of noxious stimuli by populations of neurons. In this psychophysical experiment, we hypothesized that more intense noxious stimuli would lead to spread of pain, but more intense light stimuli would not produce perceptual radiation. Fifty healthy volunteers (27 females, 23 males, ages 14-44 years) participated in this study wherein noxious stimuli (43, 45, 47, and 49°C) were applied to glabrous (hand) and hairy skin (forearm) skin with 5-second and 10-second durations. Also, visual stimuli displayed on the target bodily area were used as a control. Participants provided pain (and light) spatial extent ratings as well as pain (and light) intensity ratings. In the extent rating procedure, participants adjusted the extent of the square displayed on the screen with the extent of pain (or light) that they experienced. Pain extent ratings showed statistically significant radiation of pain indicated by 12.42× greater spatial spread of pain (pain extent) than the area of the stimulation with 49°C (P < 0.001), in contrast to visual ratings, which closely approximated the size of the stimulus (1.22×). Pain radiation was more pronounced in hairy than glabrous skin (P < 0.05) and was more pronounced with longer stimulus duration (P < 0.001). Pain intensity explained only 14% of the pain radiation variability. The relative independence of the pain radiation from pain intensity indicates that distinct components of population coding mechanisms may be involved in the spatial representation of pain vs intensity coding.

Radiation of pain: Psychophysical evidence for a population coding mechanism in humans

The spread of pain across body locations remains poorly understood but may provide important insights into the encoding of sensory features of noxious stimuli by populations of neurons. In this psychophysical experiment, we hypothesized that more intense noxious stimuli would lead to spread of pain, but more intense light stimuli would not produce perceptual radiation. Fifty healthy volunteers (27 females, 23 males, ages 14-44) participated in this study wherein noxious stimuli (43, 45, 47 and 49°C) were applied to glabrous (hand) and hairy skin (forearm) skin with 5s and 10s durations. Also, visual stimuli displayed on the target bodily area were utilized as a control. Participants provided pain (and light) spatial extent ratings as well as pain (and light) intensity ratings. In the extent rating procedure, participants adjusted the extent of the square displayed on the screen with the extent of pain (or light) which they experienced. Pain extent ratings showed statistically significant radiation of pain indicated by 12.42× greater spatial spread of pain (pain extent) than the area of the stimulation with 49°C (p<0.001), in contrast to visual ratings which closely approximated the size of the stimulus (1.22×). Pain radiation was more pronounced in hairy than glabrous skin (p<0.05) and was more pronounced with longer stimulus duration (p<0.001). Pain intensity explained only 14% of the pain radiation variability. The relative independence of the pain radiation from pain intensity indicates that distinct components of population coding mechanisms may be involved in the spatial representation of pain versus intensity coding.

Acceptability of multimodal and multidisciplinary group-based program for chronic low back pain: a qualitative study

BACKGROUND

The Programa d'Atenció Integral pels Pacients amb Dolor Crònic (PAINDOC) is a multimodal and multidisciplinary group-based program that integrates pain neuroscience education, mindfulness meditation, pain psychotherapy, Empowered Relief, and therapeutic exercise. It serves as a therapeutic option for individuals with chronic low back pain, providing them with comprehensive adaptive strategies for pain management.

OBJECTIVE

This qualitative study explores participants' retrospective acceptability of the PAINDOC Program.

METHODS

To ensure demographic variability and information power, a purposive sampling approach was applied. Twelve participants were interviewed through three focus groups, supplemented with four individual semi-structured interviews. Data was analyzed using reflexive thematic analysis and evaluated based on the Therapeutic Framework of Acceptability.

RESULTS

Participants provide positive feedback regarding active pain coping strategies and improved self-management. While certain aspects of the Program were more emphasized, participants integrated tools from all components. Strategies included pain reconceptualization, positive self-talk, or problem-solving. The Program's ethicality was closely linked to individual values and may also be influenced by time constraints of certain program elements, the immediate effects of specific approaches, participant perceptions, and individual preferences.

CONCLUSIONS

The findings provide valuable insights into the acceptability of the PAINDOC Program, guiding future improvements and the development of similar interventions.

"My Back is Fit for Movement": A Qualitative Study Alongside a Randomized Controlled Trial for Chronic Low Back Pain

A new wave of treatments has emerged to target nervous system alterations and maladaptive conceptualizations about pain for chronic low back pain. The acceptability of these treatments is still uncertain. We conducted a qualitative study alongside a randomized controlled trial to identify perceptions of facilitators or barriers to participation in a non-pharmacological intervention that resulted in clinically meaningful reductions across 12 months for disability compared to a sham intervention. We conducted semi-structured interviews with participants from the trial's active arm after they completed the 12-week program. We included a purposeful sample (baseline and clinical characteristics) (n = 20). We used reflexive thematic analysis informed by the Theoretical Framework of Acceptability for health care interventions. We identified positive and negative emotional/cognitive responses associated with treatment acceptability and potential efficacy, including emotional support, cognitive empowerment, readiness for self-management, and acceptance of face-to-face and online components designed to target the brain. These findings suggest the importance of psychoeducation and behavior change techniques to create a positive attitude towards movement and increase the perception of pain control; systematic approaches to monitor and target misconceptions about the interventions during treatment; and psychoeducation and behavior change techniques to maintain the improvements after the cessation of formal care. PERSPECTIVE: This article presents the experiences of people with chronic low back pain participating in a new non-pharmacological brain-targeted treatment that includes face-to-face and self-directed approaches. The facilitators and barriers of the interventions could potentially inform adaptations and optimization of treatments designed to target the brain to treat chronic low back pain.

Watch Your Back: Development and Usability of a Visual Feedback System for People with Low Back Pain – A Single Subject Usability Study

Background To find effective treatments for low back pain remains a major challenge in physical therapy. Numerous treatment methods currently exist, but the use of real-time visual feedback is a promising new therapeutic approach. The opportunities for its implementation and use require further research.

Objective To develop a video-supported system for visual feedback and to test its usability.

Method The prototype of a video-based system for visual feedback was developed and tested on a person with persistent unspecific lumbar back pain. The system was evaluated through an interview with the subject and the system usability scale (SUS).

Results The subject was optimistic about the system’s functionality. He was astonished to see his own back while moving, which triggered positive emotions. He also found the apparatus comfortable to wear. The system achieved a value of 77.5 out of 100 on the SUS, which represents good usability.

Conclusion By means of technical adjustments to avoid a delay in transmission and an exact positioning of the monitor, further improvements in the usability can be achieved. More research will be required to evaluate the efficacy of the developed system in the treatment of lumbar back pain.

Pain Management through Neurocognitive Therapeutic Exercises in Hypermobile Ehlers-Danlos Syndrome Patients with Chronic Low Back Pain

Background

The hypermobile type of Ehlers-Danlos syndrome (hEDS) is likely the most common hereditary disorder of connective tissue mainly characterized by joint hypermobility. Patients with hEDS suffer joint pain, in particular low back pain, commonly resistant to drug therapy. The aim of this research was to evaluate a neurocognitive rehabilitation approach based not only on the motion and function recovery but also on the pain management.

Methods

In this nonrandomized clinical trial, eighteen hEDS patients (4 males and 14 females) with mean age 21 years (range 13-55) were recruited and evaluated before and after three months of rehabilitation treatment.

Results

The outcome scores showed significant statistical results after treatment in reducing pain symptoms (numerical rating scale, P = 0.003; McGill (total score), P = 0.03), fatigue (fatigue severity scale, P = 0.03), fear of movement (Tampa scale, P = 0.003), and pain-associated disability (Oswestry disability index, P = 0.03).

Conclusion

The clinical results observed in our study seem to confirm the role of a specific neurocognitive rehabilitation program in the chronic pain management in the Ehlers-Danlos syndrome; the rehabilitation treatment should be tailored on patient problems and focused not only in the recovery of movement but also on pain perception.

Relevance of a novel external dynamic distraction device for treating back pain

Low back pain is a common, expensive, and disabling condition in industrialized countries. There is still no consensus for its ideal management. Believing in the beneficial effect of traction, we developed a novel external dynamic distraction device. The purpose of this work was to demonstrate that external distraction allows limiting the pressure exerted in standing-up position on the lower intervertebral discs. Numerical and cadaveric studies were used as complementary approaches. Firstly, we implemented the device into a numerical model of a validated musculoskeletal software (Anybody Modeling System) and we calculated the lower disc pressure while traction forces were applied. Secondly, we performed an anatomical study using a non-formalin preserved cadaver placed in a sitting position. A pressure sensor was placed in the lower discs under fluoroscopic control through a Jamshidi needle. The intradiscal pressure was then measured continuously at rest while applying a traction force of 200 N. Both numerical and cadaveric studies demonstrated a decrease in intradiscal pressures after applying a traction force with the external device. Using the numerical model, we showed that tensile forces below 500 N in total were sufficient. The application of higher forces seems useless and potentially deleterious. External dynamic distraction device is able to significantly decrease the intradiscal pressure in a sitting or standing position. However, the therapeutic effects need to be proven using clinical studies.

Hypnosis Enhances the Effects of Pain Education in Patients With Chronic Nonspecific Low Back Pain: A Randomized Controlled Trial

The potential benefits of combining pain education (PE) with clinical hypnosis (CH) has not yet been investigated in individuals with chronic pain. A total of 100 patients with chronic nonspecific low back pain were randomized to receive either: 1) PE alone, or 2) PE with CH. Outcomes were collected by a blinded assessor at 2 weeks and 3 months after randomization. The primary outcomes were average pain intensity, worst pain intensity (both assessed with 11-point numeric rating scales), and disability (24-item Roland Morris Disability Questionnaire) at 2 weeks. At 2 weeks, participants who received PE with CH reported lower worst pain intensity (mean difference = 1.35 points, 95% confidence interval [CI] = .32-2.37) and disability (mean difference = 2.34 points, 95% CI = .06-4.61), but not average pain intensity (mean difference = .67 point, 95% CI = -.27 to 1.62), relative to participants who received PE alone. PE with CH participants also reported more global perceived benefits at 2 weeks (mean difference = -1.98 points, 95% CI = -3.21 to -.75). At 3 months, participants who received PE with CH reported lower worst pain intensity (mean difference = 1.32 points, 95% CI = .29-2.34) and catastrophizing (mean difference = 5.30 points, 95% CI = 1.20-9.41). No adverse effects in either treatment condition were reported. To our knowledge, this is the first trial showing that additional use of hypnosis with PE results in improved outcomes over PE alone in patients with chronic nonspecific low back pain.

PERSPECTIVE

This study provides evidence supporting the efficacy of another treatment option for teaching patients to self-manage chronic low back pain that has a relatively low cost and that can be offered in groups.