What does the posterior interosseous nerve innervate. The nerve was wrapped in perineural fat.

What does the posterior interosseous nerve innervate. For some authors, the deep branch of the radial nerve is the same as the posterior interosseous nerve. Nov 13, 2015 · This article will focus on the five terminal nerve branches of the brachial plexus which supply the upper limb. The anterior interosseous Jul 5, 2023 · What is a Supinator Syndrome? Supinator syndrome, also known as posterior interosseous nerve syndrome, is a condition characterized by compression or irritation of the posterior interosseous nerve as it passes through the supinator muscle of the forearm. At what point does the deep br. A terminal branch of the radial nerve, the deep branch, innervates the remaining muscles of the posterior forearm. It carries fibers from the C7 and C8 spinal nerves and supplies the majority of the muscles in the posterior compartment of the forearm. The superficial branch is mostly sensory. When performing this procedure through a dorsal approach we have been impressed by anatomic variations of the AIN. Upon entering The posterior interosseous nerve (PIN) is a deep branch of the radial nerve and is principally a motor nerve. This rare form of peripheral neuropathy involves disruption of the anterior interosseous nerve, a distal motor and sensory branch The nerve reaches the anterior surface of the interosseous membrane and travels with the anterior interosseous artery to the PQ where it penetrates the muscle proximally and passes deep to the belly to innervate the muscle. The nerve can be traumatized in proximal fractures of the radius and ulna, but the more common May 1, 2023 · Posterior interosseous nerve syndrome is a compressive neuropathy of the posterior interosseous nerve which innervates the extensor compartment of the forearm. The motor branches of the radial nerve innervate the long and medial heads of triceps brachii muscle, anconeus muscles, brachialis (lateral half), brachioradialis, and extensor carpi radialis longus muscles. The tibial nerve is the larger of the two branches of the sciatic nerve. The posterior interosseous nerve, also known as the dorsal interosseous nerve, is the continuation of the deep branch of the radial nerve after it penetrates the supinator muscle. It originates from the C7 and C8 nerve roots of the brachial plexus and innervates the muscles that extend the wrist and fingers, as well as some of the muscles that supinate the forearm. 2. It carries fibres from the C7 and C8 spinal nerves and supplies the majority of the muscles in the posterior compartment of the forearm. Study with Quizlet and memorize flashcards containing terms like Another name for the Posterior interosseous nerve is what?, What does the posterior interosseous nerve innervate?, What does the anterior interosseous nerve innervate? and more. It then passes over the abductor pollicis longus muscle origin to travel along the posterior interosseous membrane. Posterior Interosseous Nerve (PIN) Syndrome is a pathology that involves pain and/or motor weakness as a result of nerve compression. Innervated by the posterior interosseous nerve. 1). It innervates the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial compartment of the forearm and the associated joints and overlying skin. It provides motor and sensory innervation to the arm and forearm and sensory innervation to the hand. It starts anterior to the lateral epicondyle of the humerus and travels through the two heads of the supinator before curving around the lateral and posterior sides of the radius as it reaches the posterior compartment of the forearm. It accompanies the anterior interosseous artery along the anterior of the interosseous membrane of the forearm, in the interval between the Supplied Structures The radial nerve is a mixed nerve that carries both motor and sensory innervation. The posterior antebrachial interosseous nerve is generally considered to be a branch or continuation of the terminal deep branch of radial nerve; however, some authors use these names of these nerves interchangeably. At the level of the extensor retinaculum, the PIN was consistently found on the radial wall of the fourth dorsal compartment covered by a sturdy fascia. In this article, we aim to review our current understanding of the etiology, pathology, diagnosis, treatment options, and published outcomes of atraumatic PIN palsy. When the radial nerve is The posterior interosseous nerve may pass over instead of perforating the supinator muscle. Radial nerve Abstract Objective The purpose of this anatomical study was to analyze the possibility of transferring radial nerve branches to the supinator muscle to reinnervate the posterior interosseous nerve (PIN) originating from the C7–T1 roots. When compressed, the patient can present with posterior interosseous nerve Origin The posterior interosseous nerve of the forearm is a continuation of the deep branch of radial nerve as it passes between the two heads of supinator muscle. Each Nov 5, 2023 · The deep branch of the radial nerve normally passes between the supinator's heads, where it becomes the posterior interosseous nerve and innervates the posterior forearm muscles. Jul 24, 2023 · The anterior interosseous nerve (AIN) is predominantly a motor neuron. One example is thumb Sep 27, 2022 · Radial Nerve Entrapment Radial nerve injury or compression can occur anywhere along the nerve’s path which might cause extensor or supinator muscle denervation. It contains mainly fibers from the anterior rami of spinal nerves C8 and T1, but may sometimes carry C7 fibers as well. This article explores the causes, signs and symptoms, and management of this entrapment. The posterior interosseous nerve (PIN) is purely motor except for sensory fibers from the muscles it innervates and joint structures. Jul 8, 2010 · I’ve made it the “ A -OK” sign, instead of just the “OK” sign, because the “A” will help to remind you about its innervation…the A nterior interosseous nerve (AIN) the AIN is a pure motor branch of the median nerve; just like the posterior interosseous nerve is a pure motor continuation of the deep branch of the radial nerve. It most commonly due to a compression at the radial tunnel. Also, this remains responsible for innervating most of the muscles in the forearm. In the distal arm the radial nerve innervates the brachialis, brachioradialis, and extensor carpi radialis longus and brevis muscles. In the distal lateral arm, the radial nerve pierces the lateral intermuscular septum passing from the posterior to the anterior compartment of the arm. It passes between the two heads of the supinator and comes to lie intimately with the proximal radius. Although its chief importance is muscular innervation, the radial nerve also carries sensory information from a significant portion of the posterior arm, forearm, and hand. The posterior interosseous nerve supplies motor innervation to the posterior forearm. Posterior interosseous nerve syndrome is a neuropathic compression of the posterior interosseous nerve where it passes through the radial tunnel. &nbsp; Summary origin: one of two terminal branches of the posterior cord Nov 21, 2023 · The deep branch is a motor branch that passes between the heads of the supinator muscle and becomes the posterior interosseous nerve to innervate the muscles of the posterior compartment of the forearm. In the proximal arm, the radial nerve innervates the medial and lateral heads of the triceps and the anconeus. Blood supply Extensor pollicis brevis receives its blood supply from the posterior interosseous artery and perforating branches of the anterior interosseous artery. The nerve was wrapped in perineural fat. Blood supply The radial nerve is a nerve in the human body that supplies the posterior portion of the upper limb. Methods Thirty members of 15 cadavers, all male, prepared with an intra-arterial glycerol and formaldehyde solution injection, were dissected. Background: This study attempted to clarify the innervation pattern of the muscles of the distal arm and posterior forearm through cadaveric dissection. Posterior interosseous nerve decompressed The supinator m. Nov 3, 2023 · Abductor pollicis longus is innervated by the posterior interosseous nerve (C7, C8), which is a continuation of the deep branch of the radial nerve. Aug 6, 2024 · Study with Quizlet and memorize flashcards containing terms like Which nerve innervates all muscles in the anterior compartment of the arm?, Which nerve innervates the palmar surface of the lateral three and one-half digits?, Which nerve supplies skin on the posterior surface of the forearm and the dorsolateral surface of the hand? and more. Additionally, there are two terminal branches, namely the superficial and the deep branches. Epidemiology Compressive neuropathies of t Nov 15, 2017 · Relations --------------- The posterior interosseous nerve runs in close proximity to the posterior interosseous artery, which also passes along the posterior aspect of the interosseous membrane. When does the radial nerve become the PIN? Mar 2, 2022 · The nerve does not provide cutaneous branches. It plays a role in the medial rotation of the arm and contributes to stabilizing the shoulder joint. Medial nerve: Crossed by brachial artery from lateral to medial just above the elbow to lie medial to brachial artery in cubital fossa. Aug 8, 2023 · 1. From the Study with Quizlet and memorize flashcards containing terms like What are the branches of the median nerve?, What does the anterior interosseous nerve innervate?, What does the Palmar cutaneous nerve innervate? and more. While the nerve descends through the proximal forearm, it courses between the flexor pollicis longus and flexor digitorum profundus muscles. It contains motor fibers which originate from the anterior horns of the C7-C8 cervical segments of the spinal cord. The radial nerve is a nerve in the human body that supplies the posterior portion of the upper limb. Nov 10, 2019 · This video presentation demonstrates the dorsal approach to the radius, importance of the anatomy. It is the largest branch, and it innervates the triceps brachii and anconeus muscles in the arm. Aug 15, 2016 · The posterior interosseous nerve (PIN) is susceptible to a number of traumatic and atraumatic pathologies. It innervates three muscles in the forearm, and an isolated palsy of these muscles is known as AIN Syndrome. The proximal forearm is the most typical area of compression where the posterior interosseous branch Posterior interosseous nerve C6, C7 roots -> innervate the supinator muscle; it provides outward rotation (supination) of the forearm. Once the deep branch exits underneath the supinator muscle, it is referred to as the posterior interosseous nerve. It is considerably diminished in size compared to the deep branch of the radial nerve. The Muscles with PIN The posterior interosseous nerve innervates Oct 30, 2023 · The anterior interosseous nerve is a branch of the median nerve. In contrast, the ulnar nerve innervates a portion of the forearm and the majority of the hand intrinsic muscles, which are crucial for precise and coordinated hand movements. <br />The second part of the video emphasizes the possible entrapment sides of the nerve and decompression of it. Mar 24, 2024 · Posterior Interosseous Nerve (PIN) Palsy is a syndrome characterised by a reduction in extensor movements of the fingers. The deep branch of the radial nerve or posterior interosseous nerve, is entirely motor. This tiny nerve arises from the posterior aspect of the median nerve, between the two heads of the pronator teres muscle. This study investigated Oct 7, 2024 · The posterior interosseous nerve, also known as the dorsal interosseous nerve, is the continuation of the deep branch of the radial nerve after it penetrates the supinator muscle. Lumbricals Extend the interphalangeal joints of the fingers. Methods: Thirty-five cadavers were dissected to expose the radial nerve in the forearm. Name an example of how this could happen A poorly fitted crutch If the radial nerve was injured at the axilla, name the motor functions that would be affected Jul 24, 2023 · The anterior interosseous nerve (AIN) is predominantly a motor neuron. From its origin, the ulnar nerve courses distally through the axilla, arm and forearm into the hand. AI generated definition based on: Essential Clinically Applied Anatomy of the Peripheral Nervous System in the Limbs, 2015 The deep motor branch and its direct continuation as the posterior interosseous nerve (a C7-C8 motor nerve and a branch of the radial nerve) travels between the two heads of the supinator muscle innervating the supinator as well as the remaining wrist, finger, and thumb extensors in the posterior compartment of the forearm. The nerve changes its name to posterior antebrachial interosseous nerve after it has crossed the supinator muscle. Wrist denervation via resection of the distal anterior interosseous nerve (AIN) and the posterior interosseous nerve (PIN) is an effective treatment for chronic wrist pain. Dec 29, 2022 · The posterior interosseous nerve, or deep branch of the radial nerve, is exclusively motor. Aug 20, 2023 · The last contribution of the median nerve to the thumb is from the anterior interosseous nerve, which travels outside of the carpal tunnel and supplies the flexor pollicis longus. It quickly bifurcates into two terminal branches - the anterior interosseous artery and the posterior interosseous artery - which descend on either side of the interosseous membrane. We will cover their anatomy and function, as well as the clinical features you would expect to find with a nerve injury. Posterior interosseous neuropathy Just distal to the elbow the radial nerve bifurcates into the superficial radial sensory and the posterior interosseous branches. &nbsp; Summary origin: one of two terminal branches of the posterior cord May 12, 2025 · Blood Supply and Innervation Forearm: Supplied by the anterior and posterior interosseous arteries (branches of the ulnar artery). Nov 3, 2023 · Extensor digiti minimi is innervated by the posterior interosseous nerve (C7, C8), which is a continuation of the deep branch of the radial nerve. When compressed, the patient can present with posterior interosseous nerve Abstract A thorough knowledge of the anatomy of the terminal branch of the posterior interosseous nerve (PIN) and its relationship to the anterior interosseous nerve (AIN) is essential in facilitating regional anesthetic blocks and planning surgical exposures for wrist surgery and arthrodesis of wrist and proximal row carpectomy. &nbsp; Summary origin: one of two terminal branches of the posterior cord. It innervates the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial compartment of the forearm and the associated joints and overlying skin. The fibers of the nerve originate from spinal cord segments C7 and C8. It may supply the anconeus muscle, extensor carpi radialis brevis (36% of cases), and the opposed surfaces of the middle and index fingers. Epidemiology Compressive neuropathies of t The posterior interosseous nerve is a nerve in the forearm. These nerve roots form the brachial plexus which divides to form the medial and lateral cords and then converge to form the median nerve. Jun 23, 2023 · Summary In summary, the posterior interosseous nerve is a branch of the radial nerve that passes through the forearm along with the posterior interosseous artery. Aug 11, 2023 · The posterior interosseous nerve is a motor branch of the radial nerve that arises in the posterior forearm. We describe a case of a posterior interosseous neuropathy presenting with the typical ‘finger drop’ and partial ‘wrist drop’. Study with Quizlet and memorize flashcards containing terms like innervation for anterior arm, innervation for posterior arm, innervation for anterior forearm and more. Innervated by nearby branches of the radial and median nerves. The muscles of the forearm can be quite daunting to learn. The goal of this study was to describe anatomical variations and clinical implications of anterior interosseous nerve. Strictly speaking, the deep branch of the radial nerve innervates brachioradialis and extensor carpi radialis longus muscles, and then descends between the two heads of supinator muscle. In general, the etiology of atraumatic PIN palsy can be divided into mechanical, which is caused by an extrinsic Apr 4, 2025 · Anterior interosseous nerve (AIN) is a terminal motor branch of the median nerve, which runs deep in the forearm along with the anterior interosseous artery. It carries fibers from the C7 and C8 spinal nerves and supplies the The Posterior Interosseous Nerve is a branch of the radial nerve which supplies muscle innervation to the muscles of the posterior forearm responsible for supination of the wrist as well as extension of the wrist, hand and fingers Jul 23, 2010 · The posterior interosseous nerve (PIN) is one of those nerves learned best by knowing the exceptions. this could lead to pain, weakness, dysfunction, or paresthesias and numbness along the sensory distribution of the nervus radialis. The median nerve primarily provides motor innervation to the flexor muscles of the forearm and hand, controlling wrist flexion and movement of the first three fingers. Oct 30, 2023 · Innervation Extensor digitorum is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8). The anterior interosseous nerve provides motor innervation to the deep muscles in the anterior compartment of the forearm, including: Flexor pollicis longus Flexor digitorum profundus - lateral aspect only (the medial aspect of this muscle is supplied by the ulnar nerve) Pronator quadratus The terminal branch of the anterior interosseous nerve travels through the posterior surface of the Apr 2, 2017 · median nerve AIN branch to FDP branch to FPL branch to pronator quadratus Course arises 5-8 cm distal to lateral epicondyle passes between two heads of pronator teres runs along the volar surface of the FDP courses distally along the interosseous membrane terminates in PQ near wrist joint Motor Innervation Motor deep forearm muscles Mar 13, 2025 · The posterior interosseous nerve (PIN) originates as the deep branch of the radial nerve and emerges after traversing the supinator muscle, continuing its course along the posterior compartment of the forearm to innervate the extensor muscles. Study with Quizlet and memorize flashcards containing terms like What are the nerve roots for the radial nerve?, The radial nerve is the largest branch of what cord?, What nerve is the largest branch of the posterior cord? and more. Study with Quizlet and memorize flashcards containing terms like Where does median it travel?, where does median nerve pass?, Where does the median nerve run? and more. In the arm, it courses posterior to the humerus in the spiral groove and penetrates the lateral intermuscular septum to exit the spiral groove and lie anterior to the lateral condyle beneath the brachioradialis muscle. In parts of the medical community, Radial Tunnel Syndrome and PIN Syndrome are one in the same, while in other parts they are different diagnoses with the same nerve involvement (Posterior Interosseous Nerve). Anatomic dissections relating the posterior interosseous nerve to the carpus, and the etiology of dorsal wrist ganglion pain. The posterior interosseous nerve provides motor innervation to the supinator muscle and the extensor muscles of the wrist and hand, including the Lateral elbow and forearm pain can be maddening for racket athletes. Sep 10, 2018 · Accordingly, the posterior interosseous nerve (PIN) branches off the radial nerve. Due to its innervation field, the median nerve enables us to perform both coarse and fine movements of the upper limb. It is the continuation of the deep branch of the radial nerve, after this has crossed the supinator muscle. Its nerve roots come from C8 and T1. Feb 2, 2013 · The lower subscapular nerve is defined as a nerve originating from the fifth and sixth cervical nerves that innervates the subscapularis muscle and the teres major muscle. The terminal branch of the posterior interosseous nerve travels distally into the floor of the 4th dorsal compartment of the wrist to innervate the dorsal wrist capsule. It originates from the brachial plexus, carrying fibers from the posterior roots Jul 24, 2023 · The anterior interosseous nerve (AIN) is predominantly a motor neuron. 4. Aug 29, 2025 · Posterior interosseous nerve syndrome&nbsp;is a nerve compression neuropathy of the posterior interosseous branch of the radial nerve, which affects the innervation of the forearm extensor compartment. The posterior interosseous nerve is a deep continuation of the deep radial motor nerve, one of two terminal branches arising 3–4 cm proximally to the supinator muscle in the forearm. Aug 29, 2025 · The posterior interosseous nerve, also known as the dorsal interosseous nerve, is the continuation of the deep branch of the radial nerve after it penetrates the supinator muscle. It is a branch of the median nerve, which is formed from the roots of the fifth, sixth, seventh, and eighth cervical nerves as well as the first thoracic nerve. Involve fascicles forming posterior interosseous nerve Clinical features Similar to PIN syndrome Early: Pain in some patients Course: May progress to involve more proximal muscles Frequency in PIN clinical syndromes: Up to 80% Brachial neuritis Mononeuritis multiplex Multifocal motor neuropathy Superficial radial nerve Nosology Cheiralgia The posterior interosseous nerve branching from the radial nerve (C6) Innervates the Supinator muscle Nov 3, 2023 · Extensor pollicis brevis is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8). Results The PIN proceeded distally on the interosseous membrane in the distal forearm together with the posterior branch of the interosseous artery. The distal supinator margin. 61 It ends by sending sensory afferent branches to the intercarpal, radiocarpal, and distal radioulnar joints. The common interosseous artery is a short but vital arterial branch arising from the ulnar artery in the proximal forearm. We shall also consider the clinical correlations of damage to the radial nerve. Study with Quizlet and memorize flashcards containing terms like Radial nerve arises from which cords of the brachial plexus?, what compartment does the radial nerve supply initially?, in the posterior compartment of the arm, where is the radial nerve? and more. Forearm supination is often preserved in radial neuropathy Jul 17, 2025 · The radial nerve is one of five main branches of the brachial plexus. Lateral two parts (2nd and 3rd fingers) innervated by median nerve. Radial nerve The radial nerve is the terminal branch of the posterior cord of the brachial plexus (C5–C8, T1). is transacted and the whole course of the posterior interosseous nerve within the muscle is visualized. Nov 3, 2023 · Innervation The innervation of all dorsal interossei is carried by the deep branch of ulnar nerve, derived from nerve roots C8 and T1. <br />Also emphasize the anatomy of the posterior interosseous nerve, how to identify and protect to nerve while exposing the proximal part of the bone radius. Aug 30, 2016 · The radial nerve is the “great extensor” of the upper arm, innervating nearly all the extensor movements in the upper extremity. 80 Aug 29, 2025 · Posterior interosseous nerve syndrome&nbsp;is a nerve compression neuropathy of the posterior interosseous branch of the radial nerve, which affects the innervation of the forearm extensor compartment. The skin that overlies the muscles is supplied by the roots C6-C8. Nerve routes Nerve route to Extensor Carpi Radialis Brevis Nerve route to Extensor Digitorum All Nerve route to Extensor Digiti Minimi Nerve route to Extensor Carpi Ulnaris Nerve route to Supinator Nerve route to Abductor Pollicis Longus Nerve route to Extensor Pollicis Brevis Nerve route to Extensor Pollicis Longus Nerve route to Extensor Indicis Key Points: Assess radial innervated muscles; check for posterior interosseous nerve branch versus radial nerve proper function: Branches of the radial nerve provide elbow extension, occasional elbow flexion (variably through the brachioradialis muscle as well as a branch to the brachialis muscle), supination of the forearm (although the biceps muscle innervated by musculocutaneous nerve is May 6, 2024 · Innervation The posterior interosseous nerve that innervates the muscle is a branch of the radial nerve, with nerve roots in spinal nerves C7 and C8. In part I of this series on posterior interosseous nerve dysfunction, Chris Mallac explains how PIN injuries differ from typical 'tennis elbow' and offers thoughts on the differential diagnosis of forearm pain in athletes. Nov 3, 2023 · Extensor digitorum is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8). The anterior interosseous nerve (volar interosseous nerve) is a branch of the median nerve that supplies the deep muscles on the anterior of the forearm, except the ulnar (medial) half of the flexor digitorum profundus. It follows a route along the ventral surface of the interosseous membrane, sending branches to the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) until reaching the pronator quadratus (PQ Aug 2, 2021 · The anterior interosseous nerve also known as the volar interosseous nerve&nbsp;arises from the median nerve in the forearm and supplies the flexor pollicis longus, pronator quadratus and the lateral portion of flexor digitorum profundus. When compressed, the patient can present with posterior interosseous nerve Oct 21, 2022 · The posterior interosseous nerve (PIN) is purely motor except for sensory fibers from the muscles it innervates and joint structures. In this article, we shall look at its anatomical course, motor and sensory functions, and the clinical significance of the nerve. Results All The posterior interosseous nerve passes through an arch within the proximal supinator, called the arcade of Frohse, so indicate that it is a potential posterior interosseous nerve entrapment site. The posterior interosseous nerve passes through an arch within the proximal supinator, called the arcade of Frohse, so indicate that it is a potential posterior interosseous nerve entrapment site. In this case, the PIN innervates all the muscles on the dorsal side of the forearm, EXCEPT the brachioradialis, extensor carpi radialis longus (ECRL), and anconeus. It begins anterior to the lateral epicondyle of the humerus and enters the posterior compartment of the forearm through the two heads of the supinator where it curves around the lateral and posterior surfaces of the radius. In some cases of spontaneous paralysis of the nerve, releasing this fibrous band released pressure on the nerve and restored function [3] Considerably diminished in size, it descends as the posterior interosseous nerve. Apr 21, 2024 · The median nerve is one of the major peripheral nerves of the upper limb, originating from the brachial plexus. (Also flex the MCPs of 2nd to 5th fingers). These branches supply deep structures of the forearm, wrist, and hand and play an The posterior interosseous nerve (PIN) innervates the posterior compartment muscle of the forearm and is a continuation of the deep branch of the radial nerve. Objectives -We conducted a study aimed to determine outcomes of patients undergoing a stand-alone posterior interosseous nerve or anterior/posterior interosseous nerve neurectomy for idiopathic wrist pain in patients who responded to preoperative injection. Blood supply The 1st dorsal interosseous muscle receives vascular supply from the first dorsal metacarpal branch of the radial artery. The posterior interosseous nerve (PIN) is the main distal branch of the radial nerve. At the palmar aponeurosis, the median nerve splits into radial and ulnar divisions, which further separate into the common palmar digital branches. Posterior interosseous nerve (C7-8) is a branch of the radial nerve that supplies motor innervation to the forearm extensor muscles Compression or injury can cause an isolated PIN palsy [1] More proximal pathologies can cause a combined palsy More common in body builders and laborers due to repetitive pronosupination Causes Peripheral neuropathy Anatomy of Posterior Interosseous Nerve (PIN) It is a branch of the radial nerve. Anterior interosseous nerve: Splits pronator teres and runs between flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP). Apr 29, 2023 · Along its course in the arm region, the radial nerve provides muscular branches that innervate the triceps brachii, anconeus, and brachioradialis muscles. [1] This may result in paresis or paralysis of the digital and thumb extensor muscles, resulting in an inability to extend the thumb and fingers at their metacarpophalangeal joints. of the radial nerve become termed the posterior interosseous nerve for the remainder of its course? Nov 2, 2023 · Median nerve: Origin and course The median nerve is a branch of the brachial plexus that supplies most of the superficial and deep flexors in the forearm, thenar and lumbrical muscles. May 21, 2025 · Motor Innervation Motor common extensors ECRB (often from radial nerve proper, but can be from PIN) Extensor digitorum communis (EDC) Extensor digiti minimi (EDM) Extensor carpi ulnaris (ECU) deep extensors Supinator Abductor pollicis longus (APL) Extensor pollicus brevis (EPB) Extensor pollicus longus (EPL) Extensor indicis proprius (EIP The posterior interosseous nerve supplies all the muscles of the posterior compartment of the forearm, except anconeus muscle, brachioradialis muscle, and extensor carpi radialis longus muscle. It supplies motor innervation to the majority of muscles in the posterior compartment of the forearm. Jun 30, 2022 · Tibialis posterior is innervated by the tibial nerve which arises from the L4 and L5 spinal nerves. The deep branch or the radial is a pure motor nerve with symptoms including weakness of finger extension, pain over the lateral elbow, and area of the radial The posterior interosseous nerve (PIN) innervates the posterior compartment muscle of the forearm and is a continuation of the deep branch of the radial nerve. The radial nerve innervates the triceps muscle, brachioradialis Jul 17, 2025 · The radial nerve is one of five main branches of the brachial plexus. In this article, we shall look at the applied anatomy of the nerve - its anatomical course, motor functions and cutaneous innervation. Jul 5, 2023 · The ulnar nerve is a terminal branch of the medial cord of the brachial plexus. The posterior interosseous nerve of forearm (Posterior antebrachial interosseous nerve) is a continuation of the deep branch of the radial nerve after it penetrates the supinator muscle and innervates the muscles in the posterior compartment of the forearm. Leg: Supplied by the anterior tibial artery, which passes through the proximal opening. The radial nerve arises from the brachial plexus posterior cord from roots C5-Th1. May 20, 2024 · The radial nerve is a major peripheral nerve of the upper limb. It usually has an insidious onset, often presenting with weakness in finger and thumb extension. Gross Jul 17, 2025 · The radial nerve is one of five main branches of the brachial plexus. PIN palsy is a rare syndrome characterized by reduced ability to extend the fingers, weakened extension and abduction of the thumb and wrist extension with a radial drift. The spinal accessory nerve is cranial nerve XI, and innervates the trapezius muscle, which elevates and depresses the scapula. After passing around the radial head the nerve, it crosses and enters the supinator muscle. Blood Supply The posterior interosseous artery supplies the superior surface of the extensor indicis. It is a mixed nerve and provides motor innervation to various muscles of the forearm and hand Feb 18, 2023 · The posterior interosseous artery itself descends on the posterior surface of the interosseous membrane alongside the posterior interosseous nerve (from the radial nerve) between the supinator (superficially) and abductor pollicis longus (deeply) muscles, supplying both. It also gives sensation to certain areas of the skin of the hand. Ulnar nerve: Between flexor carpi ulnaris (FCU) and flexor digitorum profundus (FDP). The anterior interosseous The posterior interosseous nerve is the terminal motor branch of the radial nerve that innervates the extensor carpi ulnaris and the extensors of the thumb and fingers. It supplies the deep muscles of the anterior forearm - flexor pollicis longus, lateral half of flexor digitorum profundus and pronator quadratus. [4][5] The posterior interosseous nerve is a branch of the radial nerve in the forearm. The nerve can be traumatized in proximal fractures of the radius and ulna, but the more common etiology is compression of the nerve as it passes through the supinator muscle. We describe a case of a posterior interosseous neuropathy presenting with the Aug 28, 2025 · PINS occurs when muscles innervated by the posterior interosseous nerve are affected secondary to entrapment of the posterior interosseous nerve by 1 of several structures (Fig. The radial nerve also gives rise to branches that supply the brachioradialis and extensor carpi radialis longus (muscles of the posterior forearm). History and etymology It is named after the German anatomist Fritz Frohse (1871-1916) 3. The posterior interosseous nerve provides muscular branches to extensor carpi Aug 29, 2025 · The posterior interosseous nerve, also known as the dorsal interosseous nerve, is the continuation of the deep branch of the radial nerve after it penetrates the supinator muscle. [2] Nov 7, 2015 · forearm posterior compartment winds around radial neck within substance of muscle to posterior compartment of forearm interosseous membrane reaches interosseous membrane of forearm and ends as sensation to dorsal wrist capsule dorsal wrist capsule Motor Innervation Motor common extensors ECRB (often from radial nerve proper, but can be from PIN) The radial nerve and its branches—the deep radial nerve, which continues as the posterior interosseous nerve—innervate all the posterior muscles of the arm and forearm, as might be expected based on their posterior location. Close to its The posterior terminal branch provides motor innervation to the posterior deltoid and teres minor and sensory innervation to the skin over the inferior deltoid via the upper lateral cutaneous nerve of the arm. The supinator muscle is responsible for turning the forearm from pronation (palm down) to supination (palm up). Apr 21, 2024 · The anterior interosseous nerve is a motor branch of the median nerve. May 1, 2023 · The posterior interosseous nerve supplies motor innervation to the posterior forearm. 73 Trauma, such as Nov 19, 2024 · Related pathology The deep branch of the radial nerve may become entrapped in the arcade of Frohse, leading to posterior interosseous nerve syndrome. The radial nerve is a branch of the posterior cord of the brachial plexus. Introduction: The anterior interosseous nerve (AIN) is the main branch originating from the median nerve, responsible for innervating muscles in the anterior compartment of the forearm. PIN (posterior interosseous nerve) syndrome is one of the compression neuropathies of the radial nerve near the elbow or in the forearm. Detailed understanding of the anatomy of the radial nerve helps explain the clinical presentation. It divides into two terminal branches: superficial and deep. It provides motor innervation to the deep muscles of the posterior compartment of the forearm, facilitating various hand and wrist movements. At the wrist, it passes through the 4th extensor compartment to terminate on the dorsal wrist Study with Quizlet and memorize flashcards containing terms like 5 terminal branches of the brachial plexus, what muscles does the musculocutaneous branch supply?, what muscles does the median branch supply? Cutaneous? and more. Relations --------------- The posterior interosseous nerve runs in close proximity to the posterior interosseous artery, which also passes along the posterior aspect of the interosseous membrane. These are the musculocutaneous nerve, the axillary nerve, the radial nerve, the median nerve and the ulnar nerve. Here the nerve divides into two terminal branches: the cutaneous superficial radial nerve that supplies the skin of the radial dorsal aspect of the hand and distal forearm, and the primarily motor posterior interosseous nerve. It is about 5–8 cm distal to the lateral epicondyle and 4 cm distal to the medial epicondyle. Apr 18, 2021 · The posterior interosseous nerve (PIN) is purely motor except for sensory fibers from the muscles it innervates and joint structures. The nerve fibers originate from cervical segments C7 and C8 in the spinal column. Medial two parts (4th and 5th fingers) innervated by ulnar nerve. Dec 18, 2023 · PIN compression syndrome is a compressive neuropathy of the PIN which affects the nerve supply of the forearm extensor compartment. It branches from the median nerve in the proximal forearm just below to the elbow joint. It innervates most of the extensor muscles of the forearm and contains deep sensory fibres directed to the ligaments and joints of the wrist. 1–3 Potential causes include PIN or radial nerve lesions or entrapment of the PIN as it passes through the Posterior Interosseous NervePosterior Interosseous Nerve Origin: C6, C7, C8 roots, arising as a branch from the Radial Nerve Muscles Innervated After the nerve passes the level of the elbow it becomes referred to as the deep motor branch of the radial nerve and innervates the forearm extensors muscles excluding the brachioradialis and extensor carpi radialis longus/brevis. The radial nerve arises from the posterior cord of the brachial plexus. In complete anterior interosseous nerve palsy, the patient is unable to flex the distal phalanx of the thumb and index finger; in The anterior interosseous nerve (AIN) is the terminal motor branch of the median nerve. The branch of the radial nerve that supinates the forearm is called the Posterior interosseous nerve Excessive pressure on the radial nerve can cause damage within the axilla. The terminal branch of posterior interosseous nerve: a useful donor for digital nerve grafting. Here, it also gives off two sensory branches (posterior brachial cutaneous nerve and lateral inferior cutaneous brachial nerve) that innervate the skin of the posterior aspect of the arm as well as its inferior lateral aspect. May 1, 2023 · The posterior interosseous nerve is a branch of the radial nerve, which comes off the posterior cord of the brachial plexus. 3. The posterior interosseous nerve is the terminal motor branch of the radial nerve that innervates the extensor carpi ulnaris and the extensors of the thumb and fingers. The anatomic descriptions of PIN vary among different authors. This is an uncommon condition and very challenging to diagnose. sbmnc cjufddrj ehzzsw lvfyl kmlzj dypih mjuxzlm hkdo jidkuc yganc