Lesson 1Path of Radial Nerve in the Armpit and Upper Arm: Relations to Armpit Blood Vessels, Upper Arm Bone Head, and Latissimus Dorsi MuscleHere we trace the radial nerve in the armpit and upper arm, explaining its connections to the armpit artery, upper arm bone head, latissimus dorsi muscle, and nearby tissues, focusing on spots where it can be pressed, injury risks, and paths for surgical access.
Relations to axillary artery and veinCourse around humeral head and neckRelations to latissimus dorsi and teres majorFascial tunnels and potential compression sitesSurgical approaches in the proximal armLesson 2Important Landmarks for Locating at Bedside and Surgical Access: Outer Elbow Bump, Radial Bone Head, Spiral Groove, Supinator TunnelThis part points out dependable surface and deep markers for finding the radial nerve and its branches, helping with bedside checks, ultrasound scans, and surgical access near the outer elbow bump, radial bone head, spiral groove, and supinator tunnel.
Palpation of lateral epicondyle and radial headLocating the spiral groove on the humerusIdentifying the supinator tunnel regionUltrasound landmarks for radial branchesSafe windows for surgical approachesLesson 3Key Small-Scale Anatomy: Outer Nerve Cover, Middle Nerve Cover, Inner Nerve Cover, Nerve Blood Vessels and Effects on Injury and HealingWe explain the small-scale structure of the radial nerve, covering outer cover, middle cover, inner cover, and blood vessels, showing how these parts react to stretching, pressing, and cutting, and how they affect regrowth, lump formation, and repair methods.
Epineurial structure and surgical handlingPerineurium and fascicular organizationEndoneurial tubes and axonal supportVasa nervorum and ischemic vulnerabilityMicroanatomy and regeneration patternsLesson 4Brachial Plexus Roots and Contribution to Radial Nerve (C5–T1): Back Cord Formation and Body VariationsThis part looks at how C5–T1 roots make the back cord and radial nerve, pointing out positions in the neck and armpit, common body variations, and how these affect weakness, feeling loss, and electrical test results.
C5–T1 root contributions to radial nerveTopography of trunks, divisions, and cordsPosterior cord formation and branching patternCommon root and cord anatomical variantsClinical impact of high or low root lesionsLesson 5Back Interosseous Nerve (PIN): Entry Through Supinator Muscle (Frohse Arch), Motor Branches to Forearm Straighteners, Usual Branching PatternHere we examine the back interosseous nerve, from entering the supinator muscle and Frohse arch to its motor branches for forearm straighteners, describing usual and varied branching and their role in specific weaknesses and surgery planning.
Entry beneath ECRB to supinatorArcade of Frohse anatomy and variantsIntramuscular course within supinatorMotor branches to wrist and finger extensorsPatterns in selective PIN palsiesLesson 6Spiral (Radial) Groove Structure: Position Relative to Upper Arm Bone, Branches to Triceps and Anconeus, Blood Vessel ConnectionsThis part studies the spiral groove part, describing its spot on the back upper arm bone, links to triceps and anconeus branches, nearby blood structures, and why this area is at risk in breaks, trapping, and surgery.
Surface and radiographic localizationRelations to triceps and anconeus branchesContact with posterior humeral cortexRadial collateral and profunda brachii vesselsRisk zones in humeral shaft fracturesLesson 7Ending Motor and Feeling Areas: Straightener Compartment Muscles, Triceps, Brachioradialis, Anconeus, Finger Straighteners, and Back Hand Feeling MapThis part maps ending motor and feeling areas, connecting each radial nerve branch to specific straightener muscles, triceps, brachioradialis, anconeus, and back hand skin zones, to aid exact bedside locating and electrical test reading.
Motor map of triceps and anconeusInnervation of wrist and finger extensorsBrachioradialis and ECRL innervation zonesDorsal hand and thumb sensory territoriesPatterns of overlap with median and ulnarLesson 8Common Body Variations Affecting Clinical Signs: High Split, Extra Branches, Changing Supply to Brachioradialis and ECUWe look at common radial nerve body variations, like high split, extra branches, and changing supply to brachioradialis and ECU, stressing how these change clinical signs, nerve conduction tests, and surgery hopes.
High radial bifurcation patternsAccessory branches to triceps or brachialisVariable innervation of brachioradialisECU and ECRB innervation variantsImpact on EMG and nerve conduction testsLesson 9Split at Outer Elbow Bump/Elbow: Surface Feeling Branch and Deep Branch (Back Interosseous Nerve) Body DetailsWe study the radial nerve split near the outer elbow bump, comparing the surface feeling branch and deep motor branch (PIN), their bundle setup, links to the radial bone head, and effects on trapping, injections, and surgery release.
Anatomy at the lateral epicondyleBranching into superficial and deep branchesRelations to radial head and joint capsuleFascicular topography at the bifurcationEntrapment and iatrogenic injury risksLesson 10Forearm Path of Surface Branch: Under-Skin Route, Branches to Back of Hand and Thumb Side BoxThis part traces the surface radial nerve along the forearm, detailing its under-skin path, tissue layers, branches to the back of the hand and thumb side box, and how this structure guides feeling tests, blocks, and surgery cuts.
Course deep to brachioradialisTransition to subcutaneous positionBranches to dorsum of hand and fingersAnatomic snuffbox relations and branchesSites of Wartenberg syndrome compression
