UNASSIGNED: Intramuscular (IM) injections deliver a plethora of drugs. The majority of IM-related literature details dissolution and/or pharmacokinetic (PK) studies, using methods with limited assessments of post-injection events that can impact drug fate, and absorption parameters. Food and Drug Association guidelines no longer require preclinical in vivo modeling in the U.S.A. Preclinical animal models fail to correlate with clinical outcomes, highlighting the need to study, and understand, IM drug fate in vitro using bespoke models emulating human IM sites. Post-IM injection events, i.e. underlying processes that influence PK outcomes, remain unacknowledged, complicating the application of in vitro methods in preclinical drug development. Understanding such events could guide approaches to predict and modulate IM drug fate in humans.
UNASSIGNED: This article reviews challenges in biorelevant IM site modeling (i.e. modeling drug fate outcomes), the value of technologies available for developing IM injectables, methods for studying drug fate, and technologies for training in performing IM administrations. PubMed, Web-of-Science, and Lens databases provided papers published between 2014 and 2024.
UNASSIGNED: IM drug research is expanding what injectable therapeutics can achieve. However, post-injection events that influence PK outcomes remain poorly understood. Until addressed, advances in IM drug development will not realize their full potential.

BACKGROUND: In recent years, there has been growing interest in the use of hyaluronic acid (HA) for the treatment of premature ejaculation (PE). The efficacy of this treatment is quite controversial.
OBJECTIVE: This study intended to evaluate the efficacy and safety of glans penis augmentation with HA gel for PE.
METHODS: This systematic review includes randomized controlled trials (RCTs), primary clinical trials, prospective and retrospective studies, case series, and case reports. Searches in Embase, PubMed, Cochrane, Web of Knowledge, and ClinicalTrials.gov were performed blindly by 2 reviewers.
RESULTS: Intravaginal ejaculation latency time (IELT), questionnaires about PE, glans circumference (millimeters), and adverse events.
RESULTS: Thirteen studies were included in the evaluation: 4 RCTs, 8 prospective observational studies, and 1 restrospective study. The number of patients who received HA gel on the glans penis was 706. According to the results of 2 placebo-controlled RCTs, HA gel treatment significantly improved IELT at the end of the first month (mean difference [MD], 65.44 seconds). In the first month after the HA gel injection procedure, IELT increased vs before the procedure (MD, 176.18 [95% CI, 146.89-205.48]; P < .001, I2 = 83%). When the IELT values ​​were compared at 6 months after HA gel application, IELT improved vs before the procedure (MD, 143.93 [95% CI, 124.78-163.09]; P < .001, I2 = 82). The glans circumference expanded by approximately 1.5 cm after the procedure (MD, 14.82 mm [95% CI, 12.75-16.90]; P < .001, I2 = 65%). When the side effect profile of other studies was examined, side effects were observed in 91 patients after HA gel injection applied to 598 patients (15.22%). Among these side effects, the most common were pain (n = 46, 7.69%), bulla/nodule formation (n = 25, 4.18%), and ecchymosis (n = 20, 3.34%).
CONCLUSIONS: While HA shows promise as a therapeutic option for PE, ongoing research is essential to elucidate its clinical utility, mechanisms of action, and comparative efficacy.

BACKGROUND: Contracture and thickening of the coracohumeral ligament (CHL) occur in patients with adhesive capsulitis. This adversely affects the movement and function of the shoulder joint. There is limited evidence that explores the effectiveness of an isolated steroid injection into CHL in combination with physical therapy. This prospective randomized control trial aimed to evaluate the clinical effects of ultrasound-guided corticosteroid injection compared to a sham injection into the CHL in subjects with adhesive capsulitis.
METHODS: Forty patients (23 males, 52.2 ± 8 years of age) with unilateral adhesive capsulitis (with 5.4 ± 2 months mean duration of symptoms) were randomly assigned to either the experimental or control group. Both groups received ultrasound-guided injections into the CHL. The experimental group (n=20) received corticosteroids and the control group (n=20) received a sham lidocaine injection. All subjects underwent supervised conventional physical therapy three times a week for 3 months. Subjects were evaluated for improvements in pain, range of motion, and disability at 6 and 12 weeks as compared to pre-injection baseline measurements. Data were compared statistically across groups and times at p<0.05. The CHL thickness was compared at baseline across sides using paired t-tests.
RESULTS: The experimental group showed statistically greater improvements in pain, functional scores, flexion, abduction, internal and external rotation range of motion at 12 weeks compared to the control group. Pain reduction was observed in both groups at 6 and 12 weeks, but the experimental group exhibited significantly greater reductions. The CHL was significantly thicker on the affected side as compared to the unaffected side (p<0.001).
CONCLUSIONS: This study partially supported the hypothesis. Notably, significant improvements in pain, range of motion, and functional scores were observed at 12 weeks in the experimental group. The greater improvements in pain and external rotation may have resulted in lower disability scores in the experimental group. The results emphasize the importance of targeted intervention into the CHL.

UNASSIGNED: Patellar tendonitis (PT) is a common degenerative disease of the patellar tendon that seriously affects the sports careers of elite athletes and activities of daily living of sports enthusiasts. Injection therapy is a prevalent invasive treatment for PT.
UNASSIGNED: This work comprehensively analyzes various injection treatments for PT that consider agent type and characteristics, frequency, and assessment timepoints by meta-analysis.
UNASSIGNED: PubMed, Embase, and the Cochrane Library were sources of data.
UNASSIGNED: Randomized controlled trials (RCTs) analyzing the effect of various injection strategies on the treatment of patients with PT were considered.
UNASSIGNED: Systematic review and meta-analysis.
UNASSIGNED: Level 2.
UNASSIGNED: First author, year of publication, research location, registration information, patient type, sample size, age, sex, intervention, control treatment, and follow-up period in each study were extracted.
UNASSIGNED: Nineteen RCTs were included in the analysis. In the network meta-analysis of Victorian Institute of Sports Assessment-Patellar (VISA-P) outcomes, polidocanol (standardized mean difference (SMD), 6.52; 95% CI 4.75, 8.30; P < 0.01), tenocyte-like cells (SMD, 4.08; 95% CI 2.92, 5.25; P < 0.01), and leukocyte-poor platelet-rich plasma (LP-PRP) plus high-volume image-guided injection (HVIGI) (SMD, 1.56; 95% CI 0.62, 2.50; P < 0.01) were significantly superior to noninjection conservative treatment, mainly at the 6-month follow-up timepoint. For visual analog scale results, multiple dry needling (DN) (SMD, -1.78; 95% CI -2.56, -1.00; P < 0.01), LP-PRP (SMD, -0.71; 95% CI -1.31, -0.12; P = 0.02), and LP-PRP plus HVIGI (SMD, -1.31; 95% CI -2.22, -0.39; P < 0.01) were significantly superior to blank, which was also mainly at the 6-month timepoint.
UNASSIGNED: Injection-related treatments: polidocanol, tenocyte-like cells, LP-PRP, and multiple DN showed potential short (1-3 months) or medium (6 months)-term treatment benefits. There is still no evidence for injection interventions with long-term therapeutic benefit.

Baxter\'s neuropathy is one of the overlooked causes of chronic heel pain. Diagnosing neuropathy in Baxter\'s can be challenging due to its potential occurrence as a secondary condition to other common syndromes that cause heel pain, such as plantar fasciitis, calcaneal spur, hypertrophic muscle, tenosynovitis, space-occupying lesions or trauma. Ultrasound is a reliable and easily accessible device that guides injections for the treatment of Baxter\'s neuropathy. We have written this letter as a guide, especially for beginner and professional pain specialists.

A 78-year-old woman presented to the dermatologist with linear hypopigmentation four weeks after a local corticosteroid injection. Corticosteroid injections are commonly used for various musculoskeletal conditions refractory to other conventional treatments. We discuss a case report of a patient with linear hypopigmentation in the perilymphatic distribution due to local corticosteroid injection for the treatment of carpal tunnel syndrome (CTS). Providers who routinely inject corticosteroids should discuss this rare complication prior to injections.

BACKGROUND: With the increasing use of autologous fat (AF) grafting in plastic surgery, the occurrence of complications has garnered the attention from plastic surgeons. This study aims to estimate the cerebral complications following facial AF graft injection objectively and systematically with newly published literature.
METHODS: A comprehensive literature search was conducted systematically on PubMed, Embase, Web of Science, Cochrane, and ClinicalTrials.gov for articles published between 2000 and 2023. A systematic review and meta-analysis were performed in accordance with PRISMA guidelines.
RESULTS: A total of 11 articles comprising of 37 participants were included, all of which are case reports. For AF facial filling, the incidence rate of cerebral embolism among cases of cerebral and ocular embolism was found to be 60% (95% CI 0.41-0.79). The incidence of cerebral embolism presenting with initial symptoms of unconsciousness was 69% (95% CI 0.48-0.9), with limb movement disorders was 55% (95% CI 0.26-0.84), and with vision loss was 30% (95% CI 0.12-0.49). The incidence of cerebral embolism with ophthalmic artery occlusion was 36% (95% CI 0.20-0.53), compared to was 71% (95% CI 0.48-0.95) without ophthalmic artery occlusion.
CONCLUSIONS: AF grafting is generally safe and minimally invasive. However, with its widespread use as facial injection filling for cosmetic enhancement, the incidence of cerebral complications, such as cerebral infarction, has also increased. It is imperative to properly manage high-risk factors for cerebral embolism during the perioperative period to prevent its occurrence.
METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

OBJECTIVE: To investigate the utility of preprocedural paracetamol on reducing pain scores post office-based laryngeal procedures.
METHODS: Prospective, controlled before-after comparative study.
METHODS: Controlled prospective before-after study.
METHODS: A retrospective analysis was performed of 100 patients who underwent office-based laryngeal procedures without preprocedural analgesia at our center to establish a control group. Age, sex, procedure type, and amount of substance used were documented as well as postprocedural pain score. Pain scores were recorded every 5 minutes for 30 minutes following office-based laryngeal procedures. A prospective arm of this study was then performed in which every patient undergoing office-based laryngeal procedures at our center between September 2019 and December 2020 was administered 1000 mg of paracetamol prior to their procedure. The postprocedure pain scores of the 2 groups were then compared.
RESULTS: A hundred patients were included in the retrospective arm and 75 patients were included in the prospective arm, receiving 1000 mg of paracetamol a median of 45 (interquartile range: 30-53) minutes prior to their procedure. The 2 groups were matched for age, sex, and type of laryngeal procedure. Both nonanalgesia and analgesia groups demonstrated a similar proportion of patients who experienced any pain (47% and 48%, respectively) postprocedurally. The prospective arm of this study however reported a statistically significant reduction in the magnitude of their pain scores at all points postprocedurally (P = .005).
CONCLUSIONS: Paracetamol preprocedurally reduces the severity of pain in office-based laryngeal procedures and would be a useful consideration for patients who are likely to experience significant postprocedural pain.
METHODS: Level 3.

The silicone rubber injection technique was first described in 1999 and has been used in the vascular study of neurology and head and neck dissection. Silicone rubber is durable, flexible, and inexpensive. However, the original silicone rubber injection formula perfuses poorly into the pelvis and extremities. We present a simple modification to the silicone rubber injection technique, showcasing its effectiveness in studying the vascular structures in the pelvis and extremities. We used an ordinary mold-making silicone rubber. The new formula involves mixing the silicone rubber with silicone thinner, acetone, catalyst, and resin color. The mixture is then injected into the artery until the color becomes visible under the skin. The specimen is left at room temperature for 0.5-1 h for the silicone rubber to harden. With our technique, the silicone rubber substance perfuses adequately into small arterial perforators and can penetrate into the subdermal plexus. The smallest subdermal arteries identified under a light microscope measured 6 μm. The modified silicone rubber injection technique has proven to be a valuable tool in anatomical education and surgical training.

Hallux rigidus is a degenerative arthritic condition affecting the first metatarsophalangeal joint. Prevalence in patients aged 50 years and above is estimated at 20% to 30%, with a portion being symptomatic. Conservative treatment\'s efficacy is linked to initial pain levels; though shoe modifications and insoles are commonly recommended, their true effectiveness lacks strong evidence. Injection therapy, including corticosteroids and hyaluronic acid, demonstrates varied outcomes, with about 50% of patients undergoing surgery within 1 to 2 years. The condition\'s etiology remains elusive, but recent biomechanical hypotheses hold promise.