[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Upper limb](https://durgical.com/en/anatomy/region/upper-limb/) › Interosseous membrane [Joints and ligaments](https://durgical.com/en/anatomy/system/joints-and-ligaments/) · [Upper limb](https://durgical.com/en/anatomy/region/upper-limb/) # Interosseous membrane The interosseous membrane is a strong sheet joining the radius and ulna along the forearm; it ties them together and passes load between them. Official name: Interosseous membrane of the forearm [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=upper_limb&select=interosseous_membrane_forearm&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A tough sheet between the radius and the ulna along the forearm. ## What it does Ties the two bones together and passes load from the radius to the ulna. ## Key points - Essex-Lopresti injury: a radial head fracture with a torn interosseous membrane and a disrupted distal radioulnar joint, so the [radius](https://durgical.com/en/anatomy/radius/) slides proximally - Divides the forearm into the anterior (flexor) and posterior (extensor) compartments; the anterior and posterior interosseous nerves and arteries run on its two faces - The posterior interosseous vessels pass backward above its upper edge, below the oblique cord; near its lower end the anterior interosseous artery pierces it to reach the back of the forearm - Pronation and supination turn the radius around an [axis](https://durgical.com/en/anatomy/axis/) from the centre of the radial head to the head of the [ulna](https://durgical.com/en/anatomy/ulna/); both radioulnar joints must move together ## Key facts **Attaches** Interosseous borders of the radius and ulna (fibres run down and medially from radius to ulna) **Function** Transfers load from the radius to the ulna; separates the compartments; tightest in mid-prone position ## Relations **In front** Deep flexors: [flexor digitorum profundus](https://durgical.com/en/anatomy/flexor-digitorum-profundus/) (FDP), [flexor pollicis longus](https://durgical.com/en/anatomy/flexor-pollicis-longus/) (FPL) and, distally, [pronator quadratus](https://durgical.com/en/anatomy/pronator-quadratus/); the [anterior interosseous nerve](https://durgical.com/en/anatomy/anterior-interosseous-nerve/) and artery lie directly on it **Behind** Deep extensors: [abductor pollicis longus](https://durgical.com/en/anatomy/abductor-pollicis-longus/) (APL), [extensor pollicis brevis](https://durgical.com/en/anatomy/extensor-pollicis-brevis/) (EPB), [extensor pollicis longus](https://durgical.com/en/anatomy/extensor-pollicis-longus/) (EPL) and [extensor indicis](https://durgical.com/en/anatomy/extensor-indicis/), with the [posterior interosseous nerve](https://durgical.com/en/anatomy/posterior-interosseous-nerve/) and artery **Above** A gap between its upper edge and the [oblique cord](https://durgical.com/en/anatomy/oblique-cord/), below the radial tuberosity, through which the posterior interosseous vessels pass **Below** Ends just above the distal radioulnar joint, deep to pronator quadratus ## How to find it It cannot be felt. In dissection it appears once the deep flexors or deep extensors are lifted off the bones; on ultrasound it is a thin bright line bridging the radius and ulna on a transverse scan of the mid-forearm. ## Examination - Radius pull test (during surgery, with the radial head fractured or removed): the radius is pulled along its axis; proximal migration beyond a few millimetres suggests a torn membrane, and more still suggests [TFCC](https://durgical.com/en/anatomy/triangular-fibrocartilage-complex/) injury as well ## On imaging On X-ray the clue to a membrane tear is indirect: a radial head fracture with the radius shortened at the wrist (positive ulnar variance). Ultrasound and MRI can show the central band torn or lax. ## Clinical notes - In an Essex-Lopresti injury, treating only the radial head fracture (or excising the radial head) lets the radius migrate proximally, with ulnar-sided wrist pain - After forearm shaft fractures, malunion, scarring of the membrane or a bony bridge across it (radioulnar synostosis) limits pronation and supination - In chronic longitudinal instability the central band can be rebuilt with a tendon graft or a suture construct, usually together with restoring the radial head ## Test yourself Think of the answer, then tap the question to see it. ## Which way do the fibres of the forearm interosseous membrane run, and what does that achieve? Down and medially from radius to ulna, transferring load from the radius to the ulna. ## What is the Essex-Lopresti injury? A radial head fracture with a torn interosseous membrane and a disrupted distal radioulnar joint, so the radius slides proximally. ## What does the forearm interosseous membrane separate, and what runs on its two faces? The anterior (flexor) and posterior (extensor) compartments; the anterior and posterior interosseous nerves and arteries run on its faces. ## Why is excising the radial head alone harmful in an Essex-Lopresti injury? With the interosseous membrane torn, the radius migrates proximally, causing ulnar-sided wrist pain. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/interosseous-membrane-of-the-forearm/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** membrana interossea antebrachii TA2 1761 **Official Spanish (DeCS)** Membrana interósea del antebrazo **English (TA2)** Interosseous membrane of the forearm ## Related - [Anterior interosseous nerve](https://durgical.com/en/anatomy/anterior-interosseous-nerve/) - [Interosseous arteries](https://durgical.com/en/anatomy/interosseous-arteries-of-the-forearm/) - [Radius](https://durgical.com/en/anatomy/radius/) - [Ulna](https://durgical.com/en/anatomy/ulna/) Sources: Terminologia Anatomica (TA2); [Anatomy, Shoulder and Upper Limb, Forearm Bones](https://www.ncbi.nlm.nih.gov/books/NBK545260/); [Anatomy, Shoulder and Upper Limb, Proximal Radio-Ulnar Joint](https://www.ncbi.nlm.nih.gov/books/NBK551614/); Anatomía humana (4.ª ed.), tomo 1, cap. 57: Antebrazo. Aparato de la pronosupinación. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/interosseous-membrane-of-the-forearm/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/interosseous-membrane-of-the-forearm/