A Survey on the Choice of Spinal Cord Stimulation Parameters and Implantable Pulse Generators and on Reasons for Explantation.

Objective: Spinal Cord Stimulation (SCS) is a vital treatment for chronic intractable pain. In the last few years, the field has undergone dramatic changes in new waveform and frequency introduction as well as device miniaturization. It is important to understand contemporary practice patterns regarding these parameters. Methods: We surveyed the active membership of Spine Intervention Society (SIS), and American Society of Regional Anesthesia (ASRA) on their practices regarding various aspects of Spinal Cord Stimulation therapy. Here we report on SCS waveform usage, battery types, and causes of explant in this cohort of providers. Results: There was similar degree of usage of tonic, burst, and 10 kHz usage at 71.5%, 74.1% and 61.7% respectively. Dorsal root ganglion stimulation was used by 32.6% and other modes of stimulation by 13.5%. Rechargeable systems were often or always used by 67.2% whereas 10% never used a rechargeable system. Most common cause of explant was loss of effectiveness, reported by 53.7%. Conclusion: There has been significant adoption of new waveforms in daily practice of spinal cord stimulation therapy and there is robust mixed usage of new waveforms and frequencies. Rechargeable systems are the most commonly used but primary cell is also used in significant numbers. Loss of efficacy remains the most common cause of explant for the majority of practitioners. This survey establishes practice patterns of SCS usage regarding these important variables against which future changes can be gauged.

Post Dural Puncture Headache, Managed with Epidural Blood Patch, Is Associated with Subsequent Chronic Low Back Pain in Patients: a Pilot Study.

PURPOSE OF REVIEW: Post dural puncture headache (PDPH) is a relatively common complication which may occur in the setting of inadvertent dural puncture (DP) during labor epidural analgesia and during intentional DP during spinal anesthetic placement or diagnostic lumbar puncture. Few publications have established the long-term safety of an epidural blood patch (EBP) for the treatment of a PDPH. RECENT FINDINGS: The aim of this pilot study was to examine the association of chronic low back pain (LBP) in patients who experienced a PDPH following labor analgesia and were treated with an EBP. A total of 146 patients were contacted and completed a survey questionnaire via telephone. The EBP group was found to be more likely to have chronic LBP (percentage difference 20% [95% CI 6-33%], RR 2.6 [95% CI 1.3-5.2]) and also LBP < 6 (percentage difference 24% [95% CI 9- 37%], RR 2.3 [95% CI 1.3-4.1]). There were no significant differences in the severity and descriptive qualities of pain between the EBP and non-EBP groups. Our findings suggest that PDPH treated with an EBP is associated with an increased prevalence of subsequent low back pain in parturients. The findings of this pilot study should spur further prospective research into identifying potential associations between DP, EBP, and chronic low back pain.

Epidural Blood Patch does not Contribute to the Development of Chronic Low Back Pain in Patients who Undergo Lumbar Punctures: A Pilot Study.

Purpose of Review: Post dural puncture headache (PDPH) is a known and relatively common complication which may occur in the setting of patients undergoing lumbar punctures (LP) for diagnostic or therapeutic purposes, and is commonly treated with an epidural blood patch (EBP). There have been few publications regarding the long-term safety of EBP for the treatment of PDPH. Recent Findings: The aim of this pilot study was to examine any association of chronic low back pain (LBP) in patients who experienced a PDPH following a LP, and were treated with an EBP. A total of 49 patients were contacted and completed a survey questionnaire via telephone. There was no increased risk of chronic LBP in the dural puncture group receiving EBP (percentage difference 1% [95% CI -25% - 26%], RR: 0.98 [95% CI 0.49 - 1.99]) compared to the dural puncture group not receiving EBP. There were no significant differences in the severity and descriptive qualities of pain between the EBP and non-EBP groups. Both groups had higher prevalence of back pain compared to baseline. Summary: Our findings suggest that dural puncture patients undergoing EBP do not experience low back pain with increased frequency compared to dural puncture patients not undergoing EBP. Higher prevalence of LBP compared to baseline and compared to general population was seen in both groups. However, this pilot study is limited by a small sample size and no definitive conclusion can be drawn from this observation. The findings of this study should spur further prospective research into identifying potential associations between LP, EBP and chronic low back pain.

Long-Term Outcomes of Post Dural Puncture Headache Treated With Epidural Blood Patch: A Pilot Study.

Background: Post dural puncture headache (PDPH) is a known complication which may occur in the setting of patients undergoing lumbar punctures (LP) for diagnostic or therapeutic purposes. The gold standard for treating a PDPH is an epidural blood patch (EBP). There have been few publications evaluating the long-term outcomes of PDPH treated with EBP. The aim of this pilot study was to examine the incidence of chronic headaches in dural puncture patients who received EBP versus those who did not. Methods: A retrospective case control study was performed at a single large center institution. Forty-nine patients who had intentional dural puncture were identified on chart review and completed a survey questionnaire via phone interview: twenty-six of these patients required a subsequent EBP, while twenty-three did not. The primary outcomes were the development and prevalence of chronic headaches after the procedures. There was no statistically significant difference in the prevalence of current headaches between the EBP group and Non-EBP group (54% vs. 52% p = 0.91). There were no significant differences in the rates of severity and descriptive qualities of headache between the EBP and non-EBP groups. There was higher incidence of tinnitus in the PDPH patients. Summary: This pilot study demonstrates that patients who received an EBP for treatment of a PDPH following LP are no more likely to experience chronic headaches compared to patients who do not receive an EBP. However, both the EBP group and Non-EBP group had high incidence of chronic headaches which may be related to dural puncture or a baseline trait of this cohort given the recall bias. There is a suggestion that tinnitus could be a long-term residual symptom of PDPH treated with EBP.

Novel Single Puncture Approach for Simplicity 3 Sacral Plexus Radiofrequency Ablation: Technical Note.

UNLABELLED: Radiofrequency (RF) ablation of the lateral sacral plexus has been used for the treatment of sacroiliac joint pain including as an adjunct to other palliative therapies for the treatment of painful osseous metastasis. The treatment goal is targeted ablation of the dorsal lateral branches of S1-S4. Though several techniques have been described, the Simplicity III (Neurotherm, Middleton, MA) system allows for ablation to be achieved with a single RF probe by utilizing a multi-electrode curved RF probe to create a continuous ablation line across all sacral nerves. In the standard approach, there is sequential introduction of a spinal needle along the desired ablation tract for local anesthesia followed by separate placement of the ablation probe. Though fluoroscopic guidance is utilized, multiple needle passes increase the risk of complication such as bowel perforation or probe insertion through a neural foramen. It may also extend procedure time and increase radiation dose. We illustrate a technique for Simplicity III RF ablation of the dorsal sacral plexus using a modified Seldinger approach for treatment of a patient with sacroiliac joint pain due to osseous renal cell carcinoma metastasis. The desired ablation tract is initially anesthetized via a hollow micropuncture needle. The needle is then exchanged for a peelaway sheath. The RF probe is inserted through the peelaway sheath thus ensuring the probe is placed precisely along the previously anesthetized tract allowing the procedure to be completed using a single percutaneous puncture. We believe that this approach decreases the risks of bowel perforation, patient discomfort as a result of multiple percutaneous punctures, and procedure time. KEY WORDS: Simplicity 3, sacral plexus ablation, image-guided approach, modified Seldinger, chronic sacral pain, thin wall introducer needle.

Understanding the educational value of first-year medical students' patient encounter data.

BACKGROUND: Many medical schools use patient-encounter logs to track students' clinical experiences, but few have investigated the student-user perspective to understand how students enter, review, and use patient-encounter information. AIMS: This study examines first-year medical students' use of a web-based tracking system and whether students thought logging patient-encounters was educationally valuable. METHODS: This mixed-methods study uses data from student encounter log entries, a focus group with first-year students, and a survey. Data analysis involved descriptive statistics for quantitative data, qualitative content analysis of students' free-response entries in the logs, and thematic analysis for focus group and survey responses. RESULTS: Most students logged at least one encounter (90%), but used the system substantially less than expected. Focus group and survey data indicated that students found minimal educational value in the encounter tracking system as designed, but identified several ways in which the system could be improved to better support their learning. Suggestions included clearer guidelines for use, better integration into the curriculum, a mentoring process, and provision of benchmarks or target number of specific encounter types. CONCLUSION: Student-user perspectives are crucial in optimizing information collected through patient-encounter tracking systems, and can improve both the functionality and the educational value of such systems.

Self-adjusting, isostatic exoskeleton for the human knee joint.

A knee-joint exoskeleton design that can apply programmable torques to the articulation and that self-adjusts to its physiological movements is described. Self-adjustment means that the articular torque is automatically produced around the rotational axis of the joint. The requirements are first discussed and the conditions under which the system tracks the spatial relative movements of the limbs are given. If these conditions are met, the torque applied to the joint takes into account the possible relative movements of the limbs without introducing constraints. A prototype was built to demonstrate the applicability of these principles and preliminary tests were carried out to validate the design.