None listed
Conditions
Brief summary
The primary aim of this study is to map the sensory distribution pattern and area of sensory overlap of the posterior antebrachial, medial antebrachial and lateral antebrachial cutaneous nerves (PABCN, MABCN, LABCN) of the forearm following an ultrasound-guided local anaesthetic block. The secondary aim is to map any sensory block that occurs in the hand. Results from the study will enhance our current understanding of the variability of cutaneous sensory innervation. It may clarify why some local anaesthetic nerve blocks do not produce the expected area of cutaneous sensory anaesthesia. It will benefit pain physicians when investigating and managing the cause of symptoms of injury to the cutaneous nerves of the forearm. Forearm flaps are often used by plastic surgeons to repair soft tissue defects. Sensory deficits often occur over the skin at the donor site. The results of this study will help with sensory matching when designing forearm flaps for reconstructive surgery
Interventions
This study is designed to precisely map the distribution pattern, area of sensory overlap and any proximal extension into the hand of the three antebrachial cutaneous nerves of the forearm. This has not been previously reported. The posterior ante-brachial cutaneous nerve (PABCN) medial ante-brachial cutaneous nerve (MABCN) and lateral ante-brachial cutaneous nerve (LABCN) will be located with ultrasound and separately blocked with local anaesthetic (lidocaine). The total cutaneous sensory block
This study is designed to precisely map the distribution pattern, area of sensory overlap and any proximal extension into the hand of the three antebrachial cutaneous nerves of the forearm. This has not been previously reported. The posterior ante-brachial cutaneous nerve (PABCN) medial ante-brachial cutaneous nerve (MABCN) and lateral ante-brachial cutaneous nerve (LABCN) will be located with ultrasound and separately blocked with local anaesthetic (lidocaine). The total cutaneous sensory block area (CSBA) for each individual nerve will be mapped. Sensation will be tested using a Neuropen. This device is used in the screening of peripheral neuropathy. Overlapping areas of innervation in the forearm and hand will be reported as a percentage of the total CSBA. Areas of the forearm that remain unblocked will be reported as a percentage of the total CSBA. Sensory mapping will be done for all three nerves on separate occasions. The time to complete mapping will be less than 15 minutes. The total duration of the study will be approximately one hour on 3 separate days. On the fourth day the study time will be less than 5 minutes. Mapping will be done by the PI. The PI is a senior anaesthetist with 20 years experience in regional anaesthesia. There will be no movement required of the participants for mapping. The local anaesthetic drug lidocaine will be used to anaesthetise the nerves using a small needle introduced through the skin. The purpose of the study is to mapping the sensory distribution of the cutaneous nerves of the forearm.
Sponsors
Concord Repatriation General Hospital
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Educational / counselling / training
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy volunteers, male and female aged 18-65, BMI 18-35 kg/m2.
Exclusion criteria
Known allergy to local anaesthetic drugs; injury, deformity or previous surgery to the right arm or cutaneous nerves of the forearm; pain or pre-exiting neurological deficit of the right arm; identifying features on the arm such as tattoos, moles, scars or birthmarks.
Outcome results
None listed