- Anatomy:
- this nerve is deep motor branch of radial nerve & supplies all of extrinsic wrist extensors except for the ECRL;
- radial nerve enters the anterior compartment of the arm lying deeply between brachialis medially & BR & ECRL laterally;
- PIN passes thru supinator muscle in its course from anterior to the posterior surface of the forearm;
- PIN supplies ECRB & supinator before entering arcade of Froshe;
- this arcade is fibrotendinous structure at proximal origin of supinator;
- it is the most common site for entrapment of the nerve;
- this arcade is absent in full term fetuses but is present in 30% of adults & may develop in response to repeated rotary
movement of forearm;
- note: w/ humerus frx it is important to know whether there is radial nerve palsy;
- first branches distal to the fracture site will be the ECRB and supinator muscles, and these will be the first muscle to be
re-innervated;
- infront of lateral epicondyle it divides into its 2 terminal branches, superficial radial nerve and the PIN;
- in 25% of pts, PIN actually touches dorsal aspect of radius opposite bicipital tuberosity;
- plates placed high on dorsal surface of radius may trap nerve underneath
- Posterior Interosseous Nerve Compression Syndrome:
The terminal branch of posterior interosseous nerve: a useful donor for digital nerve grafting.
Posterior interosseous nerve palsies
Posterior interosseous nerve: an anatomic study of potential nerve grafts.
A study of the posterior interosseous nerve (PIN) and the radial tunnel in 30 Thai cadavers.
Analgesic benefit, functional outcome, and patient satisfaction after partial wrist denervation
Long-Term Follow-Up Evaluation of Denervation of the Wrist.
Anatomic considerations regarding the posterior interosseous nerve at the elbow