What variables should inform needle length choice for deltoid intramuscular injection? A systematic review.

OBJECTIVES: (1) Assess the distribution of skin-to-deltoid-muscle distance (SDMD) at the deltoid intramuscular (IM) injection site; (2) its relationship with demographic and anthropometric variables and (3) Consider the findings in relation to clinical guidance on IM injection, such as COVID-19 vaccines. DESIGN: Systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: MEDLINE, EMBASE, ClinicalTrials.gov, Cochrane Library, CINAHL and SCOPUS between June and July 2021 with no publication date limit. ELIGIBILITY CRITERIA: Studies reporting measurements of the SDMD in living adults aged 16 years and older, at the deltoid IM injection site, published in English were considered. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers performed each stage of screening, data extraction and quality assessments using the Joanna Briggs Institute Critical Appraisal Checklist for analytical cross sectional studies. RESULTS: 16 105 papers were identified, of which 11 studies were suitable for review, representing 1414 participants. Heterogeneity in the definition of the deltoid IM injection site, locations measured and methods of measurement precluded meta-analysis. Evidence from ultrasound SDMD measurements demonstrated some patients in all but 'underweight' body mass index (BMI) categories, may require needles longer than 25 mm for successful IM injection. Calliper measurements overestimated SDMD compared with ultrasound. Female sex, higher BMI categories and greater weight in women were associated with greater SDMD. CONCLUSIONS: The reviewed evidence was insufficient to inform definitive needle length 'cut points' for IM injection based on demographic or anthropomorphic variables. Contemporary clinical guidance currently based on this evidence, including the site of injection and choice of needle length, may result in subcutaneous administration in a small proportion of recipients, particularly if obese or of female sex. PROSPERO REGISTRATION NUMBER: CRD42021264625.

Intramuscular Neural Distribution of the Serratus Anterior Muscle: Regarding Botulinum Neurotoxin Injection for Treating Myofascial Pain Syndrome.

The serratus anterior muscle is commonly involved in myofascial pain syndrome and is treated with many different injective methods. Currently, there is no definite injection point for the muscle. This study provides a suggestion for injection points for the serratus anterior muscle considering the intramuscular neural distribution using the whole-mount staining method. A modified Sihler method was applied to the serratus anterior muscles (15 specimens). The intramuscular arborization areas were identified in terms of the anterior (100%), middle (50%), and posterior axillary line (0%), and from the first to the ninth ribs. The intramuscular neural distribution for the serratus anterior muscle had the largest arborization patterns in the fifth to the ninth rib portion of between 50% and 70%, and the first to the fourth rib portion had between 20% and 40%. These intramuscular neural distribution-based injection sites are in relation to the external anatomical line for the frequently injected muscles to facilitate the efficiency of botulinum neurotoxin injections. Lastly, the intramuscular neural distribution of serratus anterior muscle should be considered in order to practice more accurately without the harmful side effects of trigger-point injections and botulinum neurotoxin injections.

The botulinum neurotoxin for pain control after breast reconstruction: neural distribution of the pectoralis major muscle.

INTRODUCTION: The use of the botulinum neurotoxin injection is a growing area of research and clinical activity, with a focus on its role in facilitating postoperative pain management after reconstructive breast surgery. The study aimed to find out the standard injection points for botulinum neurotoxin injection by revealing the intramuscular nerve arborization of the pectoralis major. METHODS: Sihler's technique was conducted on the pectoralis major muscles (16 cadaveric specimens). The intramuscular nerve arborization was documented relative to the inferior border of the clavicle bone and lateral border of the sternum. RESULTS: After the staining, the pectoralis major was divided into fifths transversely from the inferior border of the clavicle and vertically into fifths from the lateral border of the sternum. Intramuscular nerve arborization of the pectoralis major muscle was the largest in the middle sections of the muscle belly. DISCUSSION: The results indicate that botulinum neurotoxin should be applied to the pectoralis major in certain regions. The regions of major arborization are optimal as the most effective and most reliable points for injecting botulinum neurotoxin.

Consensus recommendations for botulinum toxin injections in the spasticity management of children with cerebral palsy during COVID-19 outbreak

Spasticity is the most common motor disturbance in cerebral palsy (CP). Lockdown in the COVID-19 outbreak has profoundly changed daily routines, and similarly caused the suspension of spasticity treatment plans. Besides, the delay in botulinum toxin (BoNT) injection, which is important in the management of focal spasticity, led to some problems in children. This consensus report includes BoNT injection recommendations in the management of spasticity during the COVID-19 pandemic in children with CP. In order to develop the consensus report, physical medicine and rehabilitation (PMR) specialists experienced in the field of pediatric rehabilitation and BoNT injections were invited by Pediatric Rehabilitation Association. Items were prepared and adapted to the Delphi technique by PMR specialists. Then they were asked to the physicians experienced in BoNT injections (PMR specialist, pediatric orthopedists, and pediatric neurologists) or COVID-19 (pediatric infectious disease, adult infectious disease). In conclusion, the experts agree that conservative management approaches for spasticity may be the initial steps before BoNT injections. BoNT injections can be administered to children with CP with appropriate indications and with necessary precautions during the pandemic.