Distal Injection Research Articles

Computed tomographic evaluation of the proximity of needles placed for perineural anesthesia of the palmar digital nerves to synovial structures in the foot: an ex vivo study.

Potential synovial penetration following palmar digital nerve blocks has not been investigated. To evaluate the proximity of needles placed for palmar digital nerve blocks to nearby synovial structures using computed tomography (CT). Descriptive observational study. In 18 cadaver forelimbs, sequential injection of the navicular bursa (NB), distal interphalangeal joint (DIPJ) and digital flexor tendon sheath (DFTS) was performed using 3, 5 and 10 mL diluted radiodense contrast medium, respectively. After each synovial injection, 25 gage needles were placed over the palmar digital nerves at the proximal aspect of the ungular cartilages (distal injections) and 1 cm further proximally (proximal injections), and CT examination was performed. Subsequently, needles were removed, and the synovial structures further distended with the same volume as for the first injection. Perineural needle placement and image acquisition were repeated. The distance between the needle tip and adjacent synovial structures was measured (mm) in reconstructed images. Results were analyzed in separate general linear mixed models, to determine the effect of needle position and synovial distension on the distance from the tip of the needle to the NB, DFTS and DIPJ. Synovial penetration was confirmed following 12/420 (3%) needle placements (NB n = 5, 1 after proximal and 4 after distal injections; DIPJ n = 2, DFTS n = 2, NB or DIPJ n = 3, all after distal injections). The mean distance from the needle tip to the NB and DIPJ was significantly smaller after the second distension (NB: p = 0.025; DIPJ: p < 0.001) and with the distal needle placements (NB: p < 0.001; DIPJ: p < 0.001). For the DFTS, the distance from the needle tip was significantly smaller with the proximal needle placements (p = 0.001). Ex-vivo study. There is a small risk of synovial penetration when performing palmar digital nerve blocks, especially when distension of adjacent synovial structures is present.

Adductor canal block techniques do not lead to involvement of sciatic nerve branches: a radiological cadaveric study

IntroductionLow and high volume mid-thigh (ie, distal femoral triangle) and distal adductor canal block approaches are frequently applied for knee surgical procedures. Although these techniques aim to contain the injectate...

Retrograde sclerotherapy of male varicocele with veno-venous shunts - incidence and management: a single-centre experience.

The aim of our study is to compare the incidence of veno-venous shunts in male varicocele and evaluate the possibility to exclude them with manual compression or/and scrotal ligation in order to carry out the procedure of retrograde sclero-embolization. In our retrospective study, all patients undergone retrograde sclerotherapy for varicocele in our Interventional Radiology Unit in the last four years were evaluated. Collaterals toward other venous shunts were identified and how many and which patients would be able to complete the procedure safely were considered. Of the 91 patients, as many as 22 (i.e., 24.17%) patients presented anatomical variants, consisting on shunting into left iliac vein (9 [9.89%]), lumbar left veins (3 [3.29%]), right iliac vein (1 [1.09%]), both iliac veins (1 [1.09%]), left femoral vein (1 [1.09%]) or a more proximal portion of the ISV itself without shunting (3 [3.29%]). Patients with duplication could benefit from a more distal injection in order to prevent back-flow; of the 19 left, nine successfully underwent sclerotherapy with manual compression or/and scrotal ligation, whereas in 10 flow through the collaterals could not be interrupted and patients were demanded for surgery. Many patients with abnormal communications between the internal spermatic vein and the iliac veins (that is, shunts towards the iliac veins) may as well undergo retrograde sclerotherapy safely if compression/ligation is applied. No large previous study highlighted the impact of veno-venous shunts in technical feasibility of retrograde sclerotherapy of varicocele.

Comparison of Distal and Proximal Local Steroid Injection for Carpal Tunnel Syndrome: a Systematic Review and Meta-analysis of Randomized Controlled Trials.

Local steroid injection (LSI) in the carpal tunnel is a mainstay of conservative treatment in patients with carpal tunnel syndrome (CTS). Currently, clinicians generally perform a conventional proximal approach (PA) or novel distal approach (DA) for LSI. Recent systematic reviews comparing the two injection methods are lacking. This systematic review and meta-analysis aimed to assess whether LSI using the DA was superior to PA in treating patients with CTS. Databases including Pubmed, Embase, and the Cochrane library were searched up to 30 May 2022 to identify relevant randomized controlled trials (RCTs) comparing the DA with the PA steroid injection in patients with CTS. The outcomes mainly included Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQs) and Functional Status Scale (BCTQf), visual analog scores (VAS), electrophysiological outcomes, pain of injection, duration of injection, or adverse events. Five RCTs involving 339 patients were identified. Pooled analysis showed that the DA group took less time [mean difference (MD) -19.91; 95% CI -34.48 to -5.35; P = 0.007] and acquired better sensory nerve action potential amplitude [standardized mean difference (SMD) -0.37; 95% CI -0.62 to -0.11; P = 0.005]. The two groups were not significantly different in terms of BCTQs and BCTQf, VAS, other electrophysiological outcomes, pain of injection, or adverse events (P > 0.05). Although providing similar improvement in pain relief or function improvement, the distal approach is superior to the proximal approach in terms of timing, without increasing other side effects. Further high-quality randomized studies are required to confirm these results.

Neospora caninum inhibits tumor development by activating the immune response and destroying tumor cells in a B16F10 melanoma model

BackgroundMelanoma is a malignant tumor with a high mortality rate. Some microorganisms have been shown to activate the immune system and limit cancer progression. The objective of this study is to evaluate the anti-melanoma effect of Neospora caninum, a livestock pathogen with no pathogenic activity in humans.MethodsNeospora caninum tachyzoites were inoculated into a C57BL/6 mouse melanoma model by intratumoral and distal subcutaneous injections. Tumor volumes were measured, and cell death areas were visualized by hematoxylin and eosin staining and quantified. Apoptosis in cell cultures and whole tumors was detected by propidium iodide (PI) and TUNEL staining, respectively. Cytokine and tumor-associated factor levels in tumors and spleens were detected by real-time quantitative polymerase chain reaction. Infiltration of macrophages and CD8+ T cells in the tumor microenvironment (TME) were detected by immunohistochemistry with anti-CD68 and anti-CD8 antibodies, respectively. Finally, 16S rRNA sequencing of mice cecal contents was performed to evaluate the effect of N. caninum on gut microbial diversity.ResultsIntratumoral and distal subcutaneous injections of N. caninum resulted in significant inhibition of tumor growth (P < 0.001), and more than 50% of tumor cells were dead without signs of apoptosis. Neospora caninum treatment significantly increased the mRNA expression levels of IL-12, IFN-γ, IL-2, IL-10, TNF-α, and PD-L1 in the TME, and IL-12 and IFN-γ in the spleen of tumor-bearing mice (P < 0.05). An increase in the infiltration of CD8+ T cells and macrophages in the TME was observed with these cytokine changes. Neospora caninum also restored the abundance of gut microbiota Lactobacillus, Lachnospiraceae, Adlercreutzia, and Prevotellaceae associated with tumor growth, but the changes were not significant.ConclusionNeospora caninum inhibits B16F10 melanoma by activating potent immune responses and directly destroying the cancer cells. The stable, non-toxic, and efficacious properties of N. caninum demonstrate the potential for its use as a cancer treatment.Graphical

Accuracy of a CBCT-based virtual injection software for vessel detection during hepatic arterial embolization

PurposeTo assess the accuracy, sensitivity, positive predictive value (PPV) and interobserver agreement of a virtual injection (VI) software that simulates selective arterial injection from nonselective cone-beam CT (CBCT) arteriography. MethodsFrom March 2019 to May 2020, 20 consecutive patients in whom a nonselective injected CBCT and a selective CT angiography (CTA) were completed in the same procedure, were retrospectively included. The position of the microcatheter tip used for selective CTA injection was identified. The VI was simulated from the exact same point on the nonselective CBCT and the two volumes were merged. VI was compared to the real injection on the selective CTA. Three interventional radiologists evaluated the accuracy using a 6-point scale (Perfect; Good; Fair; Incorrect Origin; False Negative; Non existing). Sensitivity, PPV, and Fleiss’ kappa were calculated. Numerical variables were presented as means ± standard deviations. ResultsTwenty procedures and 195 vessel segments were analyzed. Most vessels were 4th order (57/195; 29%) and 5th order (96/195; 49%). VI was classified as perfect to good in 96.8% ± 1.4 of 1st–3rd order arteries and in 83.4% ± 0.4 of 4th–5th order arteries. Interobserver agreement was substantial (Fleiss’ kappa = 0.79; 95% confidence interval = 0.73–0.84, P < 0.01). False negatives were reported with a mean of 9.4% ± 0.3. Average sensitivity was 90.6% ± 0.3 and average PPV was 92.7% ± 0.02. Fourteen false positives were noted. ConclusionCBCT-based VI software accurately simulated distal injections in the liver with high sensitivity and a substantial interobserver agreement.

89 Do Corticosteroid and Local Anaesthetic Hip Injections Administered Proximal or Distal to The Zona Orbicularis Have an Effect on Patient Satisfaction?

Abstract Aim Pubofemoral and ischiofemoral ligaments blend to make zona orbicularis. Zonaorbicularis has been suggested to force fluid from peripheral compartment to central compartment in unidirectional flow. This study aims to assess whether injection of corticosteroid with local anaesthetic injected either proximal or distal to the zona orbicularis has effect on patient satisfaction. Method This retrospective study investigated consecutive patients undergoing ultrasound guided hip injections at a single centre in the UK between November 2018 and March 2019. Patients were identified using IMPAX© picture archiving and communications system. Radiographs were assessed to see if radiopaque dye and therefore corticosteroid and local anaesthetic had been injected proximal or distal to the zona orbicularis. Clinic letters were accessed on the electronic patient record and we recorded whether patients had pain relief at 24 hours and 2 weeks following hip injection. Results 133 Patients were identified during the study period, of which 40 were included. At 24 hours post-injection 72% of patients were satisfied and 28% were unsatisfied, for which there was 76% and 70% satisfaction for proximal and distal injections respectively (p = 0.63). At 2 weeks post-injection 45% of patients were satisfied and 55% of patients unsatisfied, for which there was 47% and 44% satisfaction for proximal and distal injections respectively (p = 0.9). Conclusions Overall patient satisfaction is high following hip corticosteroid and local anaesthetic injection. No difference was found between injections proximal and distal to the zona orbicularis. Further research is needed to quantify the association between proximal and distal injections.

Efficacy of Distal Intracoronary Epinephrine and Glycoprotein IIb/IIIa Inhibitors in the Treatment of No-reflow during Percutaneous

Background: No-reflow is considered a major percutaneous coronary intervention complication, especially in primary PCI. A variety of medications have been studied for no-reflow treatment, including intracoronary nitrates, verapamil, adenosine, glycoprotein IIb/IIIa inhibitors, and epinephrine. Glycoprotein IIb/IIIa inhibitors and epinephrine are the two most promising agents for the treatment of no-reflow. Aim of work: evaluating epinephrine and glycoprotein IIb/IIIa inhibitors efficacy in treating no-reflow through local distal intracoronary injection in comparison to traditional intracoronary administration in the guiding catheter. Subjects and methods: 30 patients undergoing PCI complicated by no-reflow phenomenon. Patients were randomized to either group I where they were treated by local distal intracoronary injection of GP IIb/IIIa inhibitor and epinephrine or to group II where they received the same medications via the traditional intracoronary injection. Primary outcomes were TIMI flow, corrected TIMI frame count and TMPG, and major adverse cardiac events within 48 hours was the secondary outcome. Results: Group I had significantly superior angiographic outcomes than group II. As regards TIMI II-III flow, 86.7% of patients achieved it in versus 53.3% in group II, CTFC was 8.2versus 9.9, and in group I, 80% of patients achieved TMPG II-III, compared to 46.7 % in group II. MACE was insignificantly different between both groups. Diabetes mellitus was found to be the only predictor to be negatively associated with TIMI flow. Conclusion: Distal coronary artery local injection of a combination of GP IIb/IIIa inhibitors and epinephrine achieved superior angiographic outcomes in the treatment of refractory no-reflow in comparison with traditional intracoronary administration of the same medications.

Administration of rabies immunoglobulin: Improving evidence-based guidance for wound infiltration.

Rabies virus causes a fatal infection of the brain and spinal cord, accounting for approximately 59,000 deaths globally each year. Rabies postexposure prophylaxis (PEP), including both rabies immunoglobulin (RIG) and vaccination, is administered to 55,000 patients annually in the United States. With a nearly 100% case fatality rate, the optimal administration of rabies PEP cannot be understated. Updated rabies PEP guidelines issued by the World Health Organization (WHO) in 2018 recognized that local wound infiltration of RIG is the primary mechanism of protection, and the WHO now recommends only infiltration of wounds without distal intramuscular injection. We highlight potential points of failure involving wound infiltration of RIG, small-volume doses, and large-volume doses that may lead to suboptimal care and discuss implications of recent shifts toward evidence-based guidelines using wound type and RIG volumes.

Indices de sécurité d’une recanalisation antérograde d’occlusion coronaire chronique sans injection controlatérale en première intention. À propos d’une série consécutive de 39 cas

IntroductionCurrent guidelines for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) recommend dual coronary angiography. Aim of the studyEvaluate CTO-PCI with a single approach using safety indices through the microcatheter. Population and methodsProspective observational study with a consecutive inclusion of 39 patients (mean age of 67 years) treated by antegrade approach without scheduled contralateral angiography. Following safety indices were collected: blood backflow, distal coronary pressure waveform, selective distal contrast injection. ResultsTechnical success was obtained in 90% of the cases. Balloon dilation was used in 38% of the cases before placement of the microcatheter. Dual angiography was necessary in three cases (8%). A blood backflow and cyclic changes of the distal coronary pressure waveform were noticed in 87% and 84% of the cases, with a positive predictive value of 97% and 79% respectively, for a microcatheter location in the true lumen. Selective distal contrast injection was done in 36 cases with a visualization of the true lumen in 35 cases. One major complication was observed (3%). ConclusionCTO-PCI with a single approach is feasible using safety indices to limit the risks of major complication. The principle of a systematic dual angiography as advocated in current guidelines may deserve to be revisited.

Characterization of an Adapted Murine Model of Intrauterine Inflammation–Induced Preterm Birth

Preterm birth (PTB) affects nearly 15 million infants each year. Of these PTBs, >25% are a result of inflammation or infection. Animal models have improved our understanding of the mechanisms leading to PTB. Prior work has described induction of intrauterine inflammation in mice with a single injection of lipopolysaccharide (LPS). Herein, we have improved the reproducibility and potency of LPS in the model using two injections distal to the cervix. An in vivo imaging system revealed more uniform distribution of Evans Blue Dye using a double distal injection (DDI) approach compared with a single proximal injection (SPI). Endotoxin concentrations in vaginal lavage fluid from SPI dams were significantly higher than from DDI dams. At equivalent LPS doses, DDI consistently induced more PTB than SPI, and DDI showed a linear dose-response, whereas SPI did not. Gene expression in myometrial tissue revealed increased levels of inflammatory markers in dams that received LPS DDI compared with LPS SPI. The SPI group showed more significant overexpression in cervical remodeling genes, likely due to the leakage of LPS from the uterine horns through the cervix. The more reliable PTB induction and uniform uterine exposure provided by this new model will be useful for further studying fetal outcomes and potential therapeutics for the prevention of inflammation-induced PTB.

Interdigital injection of botulinum toxin for patients with Raynaud phenomenon

Botulinum toxin injection has demonstrated to be a simple and cost-effective option in pain reduction, promoting healing of digital ulcers, and decreasing the frequency of vasospastic attacks in patients with Raynaud phenomenon.1,2 A universal injection technique and optimal dose to achieve adequate symptom control are lacking. Some of the reported procedures, such as proximal and distal palmar injection techniques, are painful and often require sedation or anesthetic blockade.

The Effect of Botulinum Toxin Injections on Gross Motor Function for Lower Limb Spasticity in Children with Cerebral Palsy.

The aim of this study was to investigate the use of botulinum toxin type A (BoNT-A) injections and their efficacy on gross motor function for lower limb spasticity in children with spastic cerebral palsy (CP). This retrospective study included 919 injection occasions from 591 children with CP who received a lower limb BoNT-A injection between 2006 and 2016. The Gross Motor Function Measure (GMFM-88), the Modified Ashworth Scale, and the Modified Tardieu Scale were administered before and after injections. Injections were predominantly administered to children under the age of 6 years. The most common muscle injection site was the calf muscle for dynamic foot deformity. The second most commonly injected muscle was the hip adductor among 2–3 year olds and the hamstring muscle among 4–6 year olds. Distal injections were predominantly administered to high-functioning children, whereas proximal injections were typically administered to low-functioning children. Multilevel injections were mostly administered to midfunctioning children. GMFM-88 scores significantly increased post-injection for both high- and low-functioning groups. Younger age at injection and distal injection type were associated with larger improvements on the GMFM-88 at both short- and midterm follow-up. The target muscles for injection varied depending on gross motor functioning and age. Younger age at injection and distal injection type were significantly related with greater gain in gross motor function.

Opioid- and Motor-sparing with Proximal, Mid-, and Distal Locations for Adductor Canal Block in Anterior Cruciate Ligament Reconstruction

The ideal location for single-injection adductor canal block that maximizes analgesia while minimizing quadriceps weakness after painful knee surgery is unclear. This triple-blind trial compares ultrasound-guided adductor canal block injection locations with the femoral artery positioned medial (proximal adductor canal), inferior (mid-adductor canal), and lateral (distal adductor canal) to the sartorius muscle to determine the location that optimizes postoperative analgesia and motor function. The hypothesis was that distal adductor block has (1) a superior opioid-sparing effect and (2) preserved quadriceps strength, compared with proximal and mid-locations for anterior cruciate ligament reconstruction. For the study, 108 patients were randomized to proximal, mid-, or distal adductor canal injection locations for adductor canal block. Cumulative 24-h oral morphine equivalent consumption and percentage quadriceps strength decrease (maximum voluntary isometric contraction) at 30 min postinjection were coprimary outcomes. The time to first analgesic request, pain scores, postoperative nausea/vomiting at least once within the first 24 h, and block-related complications at 2 weeks were also evaluated. All patients completed the study. Contrary to the hypothesis, proximal adductor canal block decreased 24-h morphine consumption to a mean ± SD of 34.3 ± 19.1 mg, (P < 0.0001) compared to 64.0 ± 33.6 and 65.7 ± 22.9 mg for the mid- and distal locations, respectively, with differences [95% CI] of 29.7 mg [17.2, 42.2] and 31.4 mg [21.5, 41.3], respectively, mostly in the postanesthesia care unit. Quadriceps strength was similar, with 16.7%:13.4%:15.3% decreases for proximal:mid:distal adductor canal blocks. The nausea/vomiting risk was also lower with proximal adductor canal block (10 of 34, 29.4%) compared to distal location (23 of 36, 63.9%; P = 0.005). The time to first analgesic request was longer, and postoperative pain was improved up to 6 h for proximal adductor canal block, compared to mid- and distal locations. A proximal adductor canal injection location decreases opioid consumption and opioid-related side effects without compromising quadriceps strength compared to mid- and distal locations for adductor canal block in patients undergoing anterior cruciate ligament reconstruction.

The Modified Ultrasound-Guided Distal-to-Proximal Carpal Tunnel Injection With Median Nerve Hydrodissection: A Retrospective Safety Review of 827 Procedures.

Objective: The aim of this report is to describe a new ultrasound guided technique for carpal tunnel injection and median nerve hydrodissection using distal to proximal approach. Methods: From 2015 to 2019, 827 consecutive injections by distal-to-proximal approach were included using coding information to check for post-procedural skin hypopigmentation, hematoma, seroma, nerve injury, or vascular injury. Results: There were no occurrences of post-procedural skin-hypopigmentation, hematoma or seroma formation, or neurovascular injury. Conclusions: The distal approach carpal tunnel injection is a safe and effective method. It may directly inject the medication into carpal tunnel to avoid skin hypopigmentation from steroid side effect with previous report method, also it may release adhesion of median nerve with surrounding soft tissue by hydrodissection. It helps median nerve compression at outlet of carpal tunnel.

Evaluation of the iPACK block injectate spread: a cadaveric study

Background and objectivesUltrasound-guided infiltration of the interspace between the popliteal artery and capsule of the knee (iPACK) block, a new regional analgesic technique, is believed to relieve posterior knee pain,...

Feasibility and safety of cryoballoon ablation for atrial fibrillation in patients with congenital heart disease

BACKGROUNDThe prevalence of atrial fibrillation (AF) is on the rise in the aging population with congenital heart disease (CHD). A few case series have described the feasibility and early outcomes associated with radiofrequency catheter ablation of AF centered on electrically isolating pulmonary veins (PV) in patients with CHD. In contrast, cryoballoon ablation has not previously been studied in this patient population despite its theoretical advantages, which include a favorable safety profile and shorter procedural time.AIMTo assess the safety and feasibility of cryoballoon ablation for AF in an initial cohort of patients with CHD.METHODSThe study population consisted of consecutive patients with CHD and cryoballoon ablation for AF at the Montreal Heart Institute between December 2012 and June 2017. Procedural complications, acute success, and 1-year freedom from recurrent AF after a single procedure with or without antiarrhythmic drugs were assessed. Procedures were performed under conscious sedation. Left atrial access was obtained via a single transseptal puncture or through an existing atrial septal defect (ASD). Cryoballoon occlusion was assessed by distal injection of 50% diluted contrast into the pulmonary vein. At least one 240-second cryothermal application was performed upon obtaining complete pulmonary vein occlusion. Following ablation, patients were routinely followed at outpatient visits at 1, 3, 6, and 12 mo, and then annually.RESULTSTen patients, median age 57.9 (interquartile range 48.2-61.7) years, 60% female, met inclusion criteria and were followed for 2.8 (interquartile range 1.4-4.5) years. Two had moderately complex CHD (sinus venosus ASD with partial anomalous pulmonary venous return; aortic coarctation with a persistent left superior vena cava), with the remainder having simple defects. AF was paroxysmal in 8 (80.0%) and persistent in 2 (20.0%) patients. The pulmonary vein anatomy was normal in 6 (60.0%) patients. Four had left common PV (n = 3) and/or 3 right PV (n = 2). Electrical pulmonary vein isolation (PVI) was acutely successful in all. One patient had transient phrenic nerve palsy that recovered during the intervention. No major complication occurred. One year after a single ablation procedure, 6 (60%) patients remained free from AF. One patient with recurrent AF had recovered pulmonary vein conduction and underwent a second PVI procedure. A second patient had ablation of an extra-pulmonary vein trigger for AF.CONCLUSIONCryoballoon ablation for AF is feasible and safe in patients with simple and moderate forms of CHD, with an excellent acute success rate and modest 1-year freedom from recurrent AF.

Communication between the distal interphalangeal joint and the navicular bursa in the horse at Computed Tomography Arthrography.

Diffusion of drugs injected into the distal interphalangeal joint or the navicular (podotrochlear) bursa can influence diagnosis and treatment of foot pain. Previous anatomical and radiographic studies of the communication between these synovial structures have produced conflicting results and did not identify the location of any communication if present. This anatomic study aimed to assess the presence and site of communication between the distal interphalangeal joint and the navicular bursa in the horse by computed tomography arthrography. Sixty-six pairs of cadaver forelimbs were injected with contrast medium into the distal interphalangeal joint and imaged by computed tomography arthrography. The presence of a communication, location of the communication and additional structural changes were assessed. Navicular bursa opacification occurred in 7 distal limbs (5.3%) following distal interphalangeal joint injection. One limb showed a communication through the T-ligament and 6 limbs showed a communication through the distal sesamoidean impar ligament. In 3 cases, the communication through the distal sesamoidean impar ligament was associated with a distal border fragment. Our study showed that communication between the distal interphalangeal joint and navicular bursa is uncommon and inconsistent. Clinically, the presence of a communication could (1) influence the interpretation of diagnostic analgesia of the distal interphalangeal joint or the navicular bursa by facilitating the diffusion of local anaesthetic between these structures; (2) allow the drug and its potential adverse effects to spread from the treated synovial cavity to the non-targeted synovial cavity; (3) be responsible for the failure of joint drainage in the case of sepsis.

Enlarged Areas of Pain and Pressure Hypersensitivityby Spatially Distributed Intramuscular Injections ofLow-Dose Nerve Growth Factor

Intramuscular injection of nerve growth factor (NGF) causes muscle hyperalgesia without immediate pain. This double-blinded, randomized study assessed pain and muscle hypersensitivity after a single-site bolus NGF injection (5 µg) compared with 5 spatially distributed, low-dose NGF injections (1 µg, 4 cm distance) into the tibialis anterior (TA) muscles in 20 healthy subjects. Injection pain was rated on a visual analog scale. Reports of muscle pain with functional tasks (Likert scale score) and the presence of spontaneous pain were collected daily by using a diary. Pressure pain threshold (PPT), overall pain intensity (numerical rating scale), and pain areas following the TA contraction were collected at baseline; 3 hours; and 1, 3, 7, 14, and 21 days postinjection. Low immediate visual analog scale scores were associated with both injection protocols. Likert scale scores showed moderate pain intensities but no spontaneous pain, until day 12, for both injection protocols (P < .05). Reduced PPTs at the 5- and 1-µg injection sites were found after 3 hours, lasting until day 7 (P < .05). The 1-µg injection provoked decreased PPTs at day 1 (P = .036) at the proximal injection site and at day 1 (P = .02) and day 3 (P = .01) at the distal injection site. The TA muscle contraction resulted in larger pain areas and higher numerical rating scale scores at day 3 for the distributed injections compared with the single-site injection (P < .001).Perspective: Spatially distributed low-dose NGF injections induced prolonged pain, mechanical muscle hypersensitivity, and enlarged contraction-evoked pain areas. These features mirror some clinical muscle pain conditions in which diffuse pain areas and muscle hypersensitivity are present during the activities of daily living. Low-dose NGF injections may be useful for further studies of prolonged pain conditions.

ONE-POINT PROXIMAL INJECTION TECHNIQUES FOR DE QUERVAIN'S DISEASE: A CADAVERIC STUDY

PURPOSE:To investigate the success rate of dye injection into the first extensor compartment of the wrist with the one-point proximal injection technique. METHODS:Thirty-seven wrists from 19 cadavers were included in the study. The skin overlying the first extensor compartment was removed. The methylene blue was injected directly in the first extensor compartment at the point 3 cm proximal to the palpated radial styloid. The first extensor compartment was explored to identify the dispersion of dye. The success result was determined as diffusion of dye into both subcompartment of APL and EPB. The anatomical variation of the first extensor compartment and the related structure were also investigated. RESULTS: A separated compartment was found in 20 of 37 dissected cadaveric wrists. Complete and incomplete septum was presented in 7 wrists and 13 wrists, respectively. The success rate of proximal injection technique in the septum group was 90%. CONCLUSIONS:Higher success rate was observed when compare to the more distal single injection technique reported in the previous study. The proximal injection technique may use as an alternative method for steroid injection in the patient with de Quervain’s disease.