Anatomical classification and clinical application of thoracic paraspinal blocks

Comparison of Multiple Injection Costotransverse Block and Erector Spinae Plane Block for Post-Sternotomy Pain Relief in Pediatric Patients Undergoing Cardiac Surgery: A Prospective Randomized Comparative Study

OBJECTIVE

The aim of this study was to evaluate the efficacy of ultrasound-guided multiple injection costotransverse block (MICB) and compare it with erector spinae plane block (ESPB) for poststernotomy pain relief in pediatric cardiac surgical patients.

DESIGN

A prospective, randomized, double-blind, comparative study.

SETTING

At a single institution tertiary referral cardiac center.

PARTICIPANTS

A total of 90 children with acyanotic congenital heart disease requiring surgery via sternotomy.

INTERVENTIONS

Children were allocated randomly to 1 of the 3 following groups: ESPB (group 1), MICB (group 2), or Control (group 3). Participants in groups 1 and 2 received 4 mg/kg of 0.2% ropivacaine for bilateral ultrasound-guided block after induction of anesthesia. Postoperatively, intravenous paracetamol was used for multimodal analgesia, and fentanyl/tramadol was used for rescue analgesia.

MEASUREMENTS AND MAIN RESULTS

The modified objective pain score (MOPS) was evaluated at 0, 1, 2, 4, 6, 8, 10, and 12 hours postextubation. After all exclusions, 84 patients were analyzed. The MOPS score was found to be significantly lower in ESPB and MICB groups compared to the control group until 10 hours postextubation (p < 0.05), with no statistically significant difference at the 12th hour (p = 0.2198). The total intraoperative fentanyl consumption (p = 0.0005), need for fentanyl supplementation on incision (p < 0.0001), and need for rescue opioid requirement in the postoperative period (p = 0.034) were significantly lower in both the ESPB and MICB groups than the control group. There were no statistically significant differences in both primary and secondary outcomes between the ESPB and MICB groups.

CONCLUSION

Ultrasound-guided MICB was effective and comparable to ESPB for post-sternotomy pain management in pediatric cardiac surgical patients.

The efficacy of the ultrasound-guided retrolaminar block versus the classic paravertebral block in patients undergoing unilateral inguinal hernioplasty: a randomized controlled study

BACKGROUND

In daily surgical practice, inguinal hernioplasty is a frequent procedure that is frequently accompanied by severe postoperative pain. Multiple regional blocks have been described for analgesia after such operations. Retrolaminar block (RLB) is a paravertebral block (PVB) variant that provides excellent analgesia and reduces the risk of complications. This prospective trial compared the analgesic efficacy of PVB and RLB in the inguinal hernioplasty.

METHODS

The 56 patients included were randomly assigned into two equal groups according to the block performed under ultrasound guidance at the T12 level: PVB group (28 patients) and RLB (28 patients). Time until the first rescue analgesia was our primary outcome. Other outcomes included the time to perform the block, changes in intraoperative hemodynamic parameters, postoperative VAS, 24-h morphine consumption, the level of patient satisfaction, and the incidence of block-related complications.

RESULTS

Demographic data were comparable in the two groups. However, the time needed for the block was significantly shortened with the RLB (p < 0.001). Patients in the PVB groups expressed better pain scores and lower opioid consumption. Additionally, the time to the first call for opioid analgesia showed a significant prolongation in association with the PVB. There was no discernible difference in the frequency of adverse events and recorded MAP and HR.

CONCLUSION

The PVB has a superior perioperative analgesic profile compared to the RLB, which manifested in the prolonged duration to the first rescue analgesics, better pain scores, and less opioid consumption, with no significant increase in block-related complications.

Ultrasound-guided erector spinae plane block for perioperative analgesia in patients undergoing laparoscopic nephrectomy surgery: A randomized controlled trial

Study objective

Kidney neoplasms have a high incidence, and radical nephrectomy or partial nephrectomy are the main treatment options. Our study aims to investigate the use of ultrasound-guided erector spinae plane block for perioperative analgesia in patients undergoing laparoscopic nephrectomy surgery.

Design

Prospective, randomized, double-blind.

Setting

University hospital.

Patients

Our study included 50 patients (ASA I-III) who underwent laparoscopic nephrectomy at the hospital of Second Affiliated Hospital of Army Medical University.

Interventions

The patients were divided into two groups: the ESPB group and the control group. In the ESPB group, a mixture of 10 mL of 1% lidocaine, 10 mL of 0.7% ropivacaine, 0.5 μg/kg dexmedetomidine, and 5 mg of dexamethasone was administered. In the control group, 20 mL of 0.9% saline was administered.

Measurements

The primary outcome measure was the total consumption of sufentanil during the intraoperative period. Secondary outcome measures included visual analogue scale (VAS) pain scores at rest and during coughing at 1 h, 6 h, 12 h, 24 h, and 48 h postoperatively, intraoperative consumption of remifentanil, frequency of rescue analgesic administration, consumption of rescue analgesia and incidence of postoperative nausea and vomiting within 48 h.

Results

The ESPB group exhibited lower intraoperative consumption of sufentanil, lower consumption of rescue analgesia, as well as VAS scores at rest and during coughing within the first 24 h postoperatively, compared to the control group. However, no significant differences were observed in VAS scores at 48 h postoperatively, postoperative nausea and vomiting, or the need for postoperative rescue analgesia.

Conclusions

Ultrasound-guided ESPB performed in patients who underwent laparoscopic nephrectomy demonstrated a substantial decrease in intraoperative opioid consumption, as well as lower VAS scores at rest and during coughing in the postoperative period.

Postoperative analgesic options after spine surgery: finding the optimal treatment strategies

INTRODUCTION

Spine surgery is one of the most common types of surgeries performed in the United States; however, managing postoperative pain following spine surgery has proven to be challenging. Patients with spine pathologies have higher incidences of chronic pain and resultant opioid use and potential for tolerance. Implementing a multimodal plan for postoperative analgesia after spine surgery can lead to enhanced recovery and outcomes.

AREAS COVERED

This review presents several options for analgesia following spine surgery with an emphasis on multimodal techniques to best aid this specific patient population. In addition to traditional therapeutics, such as acetaminophen, non-steroidal anti-inflammatory medications, and opioids, we discuss intrathecal morphine administration and emerging regional anesthesia techniques.

EXPERT OPINION

Several adjuncts to improve analgesia following spine surgery are efficacious in the postoperative period. Intrathecal morphine provides sustained analgesia and can be instilled intraoperatively by the surgical team under direct visualization. Local anesthetics deposited under ultrasound guidance by an anesthesiologist trained in regional techniques also provide the opportunity for single injections or continuous analgesia via an indwelling catheter.

Surgical versus nonsurgical management of lumbar degenerative spondylolisthesis based on spinal canal cross-sectional area

Disability and pain associated with lumbar degenerative spondylolisthesis (LDS) result in a significant burden on both the healthcare costs and patients' quality of life. Currently, there exists controversy regarding employment of either nonsurgical management (NSM) or surgical management (SM) in a clinical setting. Spinal canal cross-sectional area (SCA) has been an important morphological parameter for the analysis of LDS. However, there is lack of research about the comparative value of NSM and SM according to SCA. Moreover, previous research have not yet evaluated the clinical most suitable cutoff values of SCA. The objective of this research was to evaluate the effective of NSM and SM for LDS using SCA as an objective morphological parameter. The axial T2 magnetic resonance imaging images were obtained from each patient. We collected SCA samples from 149 patients with LDS. 72 patients underwent SM and the rest did NSM. We measured SCA at the L4/5 LDS on magnetic resonance imaging using a picture archiving and communications system. We measured SCA at the intervertebral disk posterior border, turning down to reach the facet joint side on the opposite edge at the L4/5 level. The average SCA value was 114.34 ± 48.11 mm2 in the NSM group and 69.88 ± 27.87 mm2 in the SM group. Therefore, the SM group had considerably lower SCA (P < .001). In view of the effectiveness of SCA as a prediction factor of surgical option, Receiver Operating Characteristic curve analysis show the optimal cutoff value for SCA as 83.21 mm2, with 70.8% sensitivity, 71.4% specificity, and an area under the curve of 0.80 (95% CI, 0.73-0.87). The narrower the SCA, the higher the probability of SM. Thus, it is proposed that to evaluate surgical decision making, the pain physician should carefully inspect the SCA.

Ultrasound-guided erector spinae plane block for perioperative analgesia in patients undergoing laparoscopic nephrectomies surgery: a randomized controlled trial

BACKGROUND

Laparoscopic nephrectomy is a commonly utilized surgical approach for the management of renal cancer. Despite its widespread acceptance, postoperative pain management remains a significant challenge for many patients undergoing this procedure. Traditional pain management techniques, including opioid and nonsteroidal anti-inflammatory drug administration, may not provide adequate pain relief and may result in adverse effects. In recent years, erector spinae plane block (ESPB) has emerged as a promising regional anesthesia technique due to its simplicity, safety, and potential efficacy in reducing postoperative pain. ESPB has demonstrated effectiveness in reducing postoperative pain in various surgical procedures. However, the efficacy of ESPB in laparoscopic nephrectomy for renal cancer has not been extensively studied. As such, further investigation is necessary to determine the potential benefits of ESPB in this context. The addition of adjuvants such as dexmedetomidine and dexamethasone to nerve blocks has been shown to improve both the duration and quality of the block. Multiple studies have demonstrated the safety and efficacy of these adjuvants in reducing postoperative pain and opioid consumption and improving patient satisfaction. The use of dexmedetomidine and dexamethasone as adjuvants for nerve blocks represents a promising approach for enhancing regional anesthesia and analgesia. In light of these findings, we have incorporated dexmedetomidine and dexamethasone into our nerve block protocol.

METHODS

This study is a randomized controlled trial conducted at a single center, with 50 participants being randomized in a 1:1 ratio to either the ESPB group or the control group. The trial aims to investigate the efficacy of ESPB in patients diagnosed with kidney cancer who are scheduled for laparoscopic nephrectomy. The primary outcome measure is the total consumption of intraoperative sufentanil. Secondary outcomes include the VAS score at rest and during coughing at 1 h, 6 h, 12 h, 24 h, and 48 h after surgery; total intraoperative remifentanil consumption; the number of times rescue analgesia is required; and the incidence of nausea and vomiting in the first 24 h after surgery. This study is registered for a duration of 1 year and is being conducted in China.

DISCUSSION

The objective of our study is to evaluate the potential benefits of erector spinae plane block (ESPB) in patients undergoing laparoscopic nephrectomy, with a focus on the impact of dexmedetomidine and dexamethasone as adjuvants on the quality and duration of the block, as well as postoperative pain and opioid consumption. By investigating the effects of these adjuvants in the context of ESPB, we hope to contribute to the growing body of literature on the use of adjuvants in nerve blocks and provide further insight into the potential benefits of this approach for improving patient outcomes following laparoscopic nephrectomy. This trial was approved by the Ethics Committee of the Second Affiliated Hospital of Army Medical University.

TRIAL REGISTRATION

China Clinical Trial Register ChiCTR2300068578 . Registered on 20 February 2023.

The analgesic effect of transmuscular quadratus lumborum block versus erector spinae plane block for women undergoing elective Caesarean section: A randomized controlled trial

Background

We aimed to compare the analgesic effect and quality of recovery of transmuscular quadratus lumborum block (QLB) and erector spinae plane block (ESPB) in the presence of multimodal analgesia following Caesarean section.

Methods

This randomised controlled trial included full-term pregnant women who underwent elective Caesarean section under spinal anaesthesia without intrathecal morphine. The included women were randomised to receive either bilateral QLB (n = 51) or bilateral thoracic ESPB (n = 51), in addition to the control group (n = 51) who did not receive any block. All participants received regular paracetamol (1 g/6h) and diclofenac (50 mg/8 h). Intravenous morphine was used as a rescue analgesic. The primary outcome was time to first morphine requirement. Secondary outcomes included total postoperative morphine consumption and total Obstetric Quality of Recovery-11 (ObsQoR-11) score.

Results

We analysed 51, 50 and 48 patients in the QLB, ESPB and control groups, respectively. The time to first morphine requirement in both QLB and ESPB groups was longer than that in the control group (median [quartiles] time: 6 [6,12] h, 6 [6,6] h and 4 [3,4] h, respectively; p-value <0.001), without significant differences between the two former groups. The total morphine consumption in both QLB and ESPB groups was lower than that in the control group (median [quartiles]:0 [0,5] mg, 0 [0,5] mg and 25 [25,30] mg, respectively; p-value <0.001), without significant differences between the two former groups. The QLB and ESPB groups had comparable ObsQoR-11 score, and both groups' scores were higher than the control group.

Conclusion

In patients undergoing elective Caesarean section under spinal anaesthesia without intrathecal morphine, both QLB and ESPB provided superior analgesia and quality of recovery compared to the standard care, without significant difference between the two blocks.

Evaluating two approaches to the erector spinae plane block: an anatomical study

BACKGROUND AND OBJECTIVES

Studies show variable spread with thoracic erector spinae plane (ESP) injections. Injection sites vary from lateral end of the transverse process (TP) to 3 cm from the spinous process, with many not describing the precise site of injection. This human cadaveric study examined dye spread of ultrasound-guided thoracic ESP block at two needle locations.

METHODS

Ultrasound-guided ESP blocks were performed on unembalmed cadavers. Methylene blue (20 mL, 0.1%) was injected in the ESP at the medial TP at level T5 (medial transverse process injection (MED), n=7) and the lateral end of the TP between T4 and T5 (injection between transverse processes (BTWN), n=7). The back muscles were dissected, and the cephalocaudal and medial-lateral dye spread documented.

RESULTS

Dye spread cephalocaudally from C4-T12 in the MED group and C5-T11 in the BTWN group, and laterally to the iliocostalis muscle in five MED injections and all BTWN injections. One MED injection reached serratus anterior. Dorsal rami were dyed in five MED and all BTWN injections. Dye spread to the dorsal root ganglion and dorsal root in most injections, though more extensively in the BTWN group. The ventral root was dyed in 4 MED and 6 BTWN injections. Epidural spread in BTWN injections ranged from 3 to 12 levels (median: 5 levels), with contralateral spread in two cases and intrathecal spread in five injections. Epidural spread in MED injections was less extensive (median (range): 1 (0-3) levels); two MED injections did not enter the epidural space.

CONCLUSION

An ESP injection administered between TPs exhibits more extensive spread than a medial TP injection in a human cadaveric model.

Comparison of Ultrasound-Guided Versus Anatomical Landmark-Guided Thoracolumbar Retrolaminar Techniques in Canine Cadavers

The retrolaminar block was developed in humans as an easier and safer alternative to the thoracic paravertebral block. This study aims to describe an ultrasound-guided thoracolumbar retrolaminar injection in canine cadavers and compare the injectate distribution between a landmark-guided and an ultrasound-guided thoracolumbar retrolaminar technique using computed tomography. Ten canine cadavers were randomised to receive two injections each of 0.6 mL/kg of iodinated contrast at the level of the twelfth thoracic vertebra (T12): a landmark-guided retrolaminar injection was performed on one hemithorax (group B, n = 10) and an ultrasound-guided on the other hemithorax (group U, n = 10). Groups were compared using the Mann-Whitney U test. The median (range) spread of the contrast in the paravertebral space was 0 (0-3) and 1 (0-5) vertebrae in groups B and U, respectively (p = 0.038). The median (range) extent of the spread surrounding the interverbal foramina was 4 (0-5) in group B and 4 (3-5) in group U. The median (range) spread along the retrolaminar space cranial and caudal to T12 was 3 (0-6) retrolaminar segments in group B and 3 (3-4) in group U. The potential of the ultrasound-guided retrolaminar injection to provide analgesia for dogs suffering from thoracolumbar pain should be further investigated.

Efficacy of the Erector Spinae Plane Block for Quality of Recovery in Bariatric Surgery: a Randomized Controlled Trial

BACKGROUND

Postoperative pain management after bariatric surgery is difficult due to different physiological properties and high sensitivity toward opioids in patients with obesity. It has been reported that erector spinae plane block (ESPB) contributes to postoperative analgesia when applied together with multimodal analgesia.

METHODS

Eighty patients were randomized either bilateral ESPB (group E) each side or no block (group C). Our primary aim was to evaluate the effects of ESPB on the quality of recovery 24 h postoperatively in bariatric surgery by using 40-item Quality of Recovery-40 (QoR-40) questionnaire. Postoperative pain assessed using a numerical rating scale (NRS), time of additional analgesic requirement, analgesic consumption, side effects, sedation, mobilization time, and postoperative complications were evaluated as secondary outcomes.

RESULTS

Postoperative mean QoR-40 scores were found to be higher in group E (175.02 ± 11.25) than in group C (167.78 ± 18.59) at the postoperative 24th hour (P < 0.05). Pain scores at rest and during movement were higher in group C than in group E. At the postoperative 24th hour, NRS mean SD scores at rest for group C and group E were 3.25 ± 1.32 and 2.40 ± 0.96, respectively. NRS mean SD scores during movement for groups C and E were 3.88 ± 1.49 and 3.12 ± 1.30, respectively. The total amount of tramadol consumed in the first 24 h in group C and group E were mean SD: 86.40 ± 69.60 and 40.00 ± 46.96, respectively; P < 0.05.

CONCLUSIONS

ESPB improved postoperative quality of recovery, reduced NRS scores, and total analgesic consumption in patients with obesity undergoing bariatric surgery.

CLINICAL TRIAL REGISTRATION

NCT05020379.

Comparing postoperative analgesia of bilateral serratus anterior plane block and thoracic paravertebral block for children following the Nuss procedure: protocol for a randomised, double-blind, non-inferiority clinical trial

INTRODUCTION

The Nuss procedure, despite being a minimally invasive surgery, is regarded as one of the most painful surgical procedures in children, and postoperative pain control remains a major clinical issue in this population. Thoracic paravertebral nerve block (TPVB) is reported as excellent pain relief for the Nuss procedure despite its challenging performance and associated adverse effects. Serratus anterior plane block (SAPB) is a simplified and effective method for managing thoracic pain as an alternative to TPVB. However, whether SAPB can provide analgesia comparable with that provided by the TPVB approach in children undergoing the Nuss procedure is unknown.

METHODS AND ANALYSIS

This will be a prospective, randomised, double-blind, single-centre, non-inferiority trial that will enrol children aged 7-16 years subjected to the Nuss operation for pectus excavatum. In total, 74 paediatric patients will be randomly assigned to either the SAPB or TPVB group after general anaesthesia to receive ultrasound-guided regional nerve blocks (0.25% ropivacaine 2.5 mg/kg). The primary outcome will be the assessment of postoperative pain intensity at predetermined time points. The secondary outcomes will include assessing intraoperative opioid intake, consumption of analgesics within 24 hours postoperatively, time of first use of rescue analgesics, extubation time, perioperative adverse events and plasma ropivacaine concentrations across the block groups. Demographic and clinical characteristics (eg, pectus severity and the number of bars used) of the patients will be recorded. All data will be collected by investigators who are blinded to the treatment.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Ethics Committee on Biomedical Research of the West China Hospital of Sichuan University (2021-1275). During the period of the study, all procedures will be conducted following the principles of the Declaration of Helsinki. The results of the trial will be published in a peer-reviewed scientific journal.

TRIAL REGISTRATION NUMBER

ChiCTR2200056596.

Comparison between costotransverse foramen block and thoracic paravertebral block for VATS pulmonary resection: A randomized noninferiority trial

STUDY OBJECTIVE

The present study assessed whether costotransverse foramen block (CTFB) is noninferior to thoracic paravertebral block (TPVB) for postoperative analgesia in video-assisted thoracoscopic surgery (VATS) pulmonary resection.

DESIGN

Single-center, double-blinded, randomized, non-inferiority trial.

SETTING

Operating room and intensive care unit or ward in a tertiary hospital.

PATIENTS

Patients aged 20 to 80 years with American Society of Anesthesiology physical status 1 to 3 scheduled for elective VATS pulmonary resection.

INTERVENTIONS

Sixty patients were randomly allocated 1:1 to receive CTFB or TPVB using 15 mL aliquots of 0.5% ropivacaine at the T4-5 and T6-7 intercostal levels immediately after the induction of general anesthesia.

MEASUREMENTS

The primary outcome was the area under the curve (AUC) of numeric rating scale (NRS, 0 to 10) during 24 h postoperatively (noninferiority limit was 24; NRS 1 per hour). The secondary outcomes included postoperative opioid consumption, rescue analgesic use, postoperative nausea and vomiting, pulmonary function, dermatomal spread of the blockade, and quality of recovery.

MAIN RESULTS

Forty-seven patients were included for final analysis. The difference between the mean 24-h AUCs of NRS in the CTFB (34.25 ± 16.30, n = 24) and TPVB (39.52 ± 17.13, n = 23) groups was -5.27 (95% confidence interval [CI], -15.09 to 4.55), with the upper limit of 95% CI being far below the predefined noninferiority margin of 24. There was no significant difference in the dermatomal spread of the blockades between the groups, as both reached the upper and lower most levels of T3 and T7 (median). Additionally, there were no significant differences in other secondary outcomes between the two groups.

CONCLUSIONS

The analgesic effect of CTFB was noninferior to that of TPVB during 24 h postoperatively in VATS pulmonary resection. Moreover, CTFB may offer potential safety benefits by keeping the tip of the needle far from the pleura and vascular structure.

Bolus intertransverse process block and continuous erector spinae plane block for perioperative analgesic management of video-assisted thoracoscopic surgery - Three cases report

BACKGROUND

Common regional anesthesia approaches for video-assisted thoracoscopic surgery (VATS) include paravertebral block (PVB) and erector spinae plane block (ESPB). PVB is considered a deep nerve block which is contraindicated in antithrombotic therapy. ESPB is effective when administered as a bolus, as well as continuously. However, the recently proposed intertransverse process block (ITPB) ensures more effective diffusion of the local anesthetic into the paravertebral space.

CASE

We report cases of three patients who received bolus ITPB (costotransverse foramen block and mid-point transverse process-to-pleura block in one and two cases, respectively) combined with continuous ESPB when a deep nerve block could not be administered. Opioids were not required postoperatively, and all postoperative numerical rating scale scores (0-10) at rest were maintained below 4.

CONCLUSIONS

The combination of bolus ITPB and continuous ESPB may be an alternative analgesic method when deep nerve blocks are contraindicated in VATS.

Erector spinae plane block versus subcostal transversus abdominis plane block in patients undergoing open liver resection surgery: A randomized controlled trial

BACKGROUND

The aim of this study was to compare the analgesic efficacy of erector spinae plane block (ESPB) in relation to subcostal transversus abdominis plane block (TAPB) in patients undergoing open liver resection surgery.

METHODS

In this randomized controlled trial, we included adult patients undergoing open liver resection surgery. After induction of general anaesthesia, the included patients were randomized to receive either ESPB (n = 30) or subcostal TAPB (n = 30). Postoperative pain was assessed using the numeric rating scale (NRS) at rest and during cough. Intravenous morphine boluses were used for management of breakthrough pain intra- and postoperatively. The study's primary outcome was morphine consumption during the first 24 h postoperatively. Secondary outcomes included intraoperative morphine consumption, time to first postoperative morphine requirement, incidence of complications, and patient satisfaction.

RESULTS

Sixty patients were included and were available for the final analysis in this study. The intra-and postoperative morphine consumption were less in the ESPB group than the subcostal TAPB group (median [quartiles] morphine dose: 0 [0-0] vs 2 [0-5] mg, p = 0.007 and 20 [15-20] vs 25 [20-30] mg, p = 0.006, respectively). The time to first morphine requirement was longer in the ESPB group (median [quartiles]: 6.5 [5.5-6.5] h) than the subcostal TAPB group (median [quartiles]: 4.3 [1.0-6.5] h), P = 0.013. Patients in the ESPB group had lower incidence of sedation and higher level of satisfaction than the subcostal TAPB group.

CONCLUSION

In patients undergoing open liver resection surgery, ESPB provided superior analgesic properties than subcostal TAPB.

CLINICAL TRIAL REGISTRATION

NCT05253079, Principal investigator: Maha Mostafa, Date of registration: February 23, 2022. URL: https://clinicaltrials.gov/ct2/show/NCT05253079.

Current evidence of ultrasound-guided fascial plane blocks for cardiac surgery: a narrative literature review

Fascial plane blocks are useful for multimodal analgesia after cardiac surgery since they can provide effective analgesia without the serious risks associated with conventional techniques such as neuraxial hematoma and pneumothorax. This narrative review covers blocks performed at the parasternal intercostal, interpectoral, pectoserratus, serratus anterior, erector spinae, and retrolaminar planes, which are targets for fascial plane blocks in cardiac surgery. Brief anatomical considerations, mechanisms, and currently available evidence are reviewed. Additionally, recent evidence on fascial plane blocks for subcutaneous-implantable cardioverter-defibrillator implantation are also reviewed.

A new diagnostic morphological parameter for the Carpal tunnel syndrome: The palmaris longus tendon cross-sectional area

Carpal tunnel syndrome (CTS) is correlated with increased intracarpal canal pressure (ICP). The effect of palmaris longus tendon (PLT) loading on ICP is documented in previous researches. PLT loading induces the greatest absolute increase in ICP. Therefore, to analyze the connection between the PLT and CTS, we newly made the measurement of the PLT cross-sectional area (PLTCSA). We assumed that PLTCSA is a reliable diagnostic parameter in the CTS. PLTCSA measurement data were acquired from 21 patients with CTS, and from 21 normal subjects who underwent wrist magnetic resonance imaging (W-MRI). We measured the PLTCSA at the level of pisiform on W-MRI. The PLTCSA was measured on the outlining of PLT. The two different cutoff values in the analysis were determined using receiver operating characteristic (ROC) analysis. The mean PLTCSA was 2.34 ± 0.82 mm2 in the normal group and 3.97 ± 1.18 mm2 in the CTS group. ROC curve analysis concluded that the best cutoff point for the PLTCSA was 2.81 mm2, with 76.2% sensitivity, 71.4% specificity, and area under the curve of 0.88 (95% CI, 0.78-0.98). PLTCSA is a sensitive, new, objective morphological parameter for evaluating CTS.