Median Nerve: Anterior Interosseous Nerve Syndrome
Anterior interosseous nerve syndrome is a rare form of median nerve compression. Along with pronator syndrome, it comprises a small percentage of compression neuropathies in the upper extremity. Symptomatically, these disorders can encompass a range of symptoms from disruptions of normal sensation through profound weakness of the forearm musculature innervated by the anterior interosseous nerve. Initial treatment is nonsurgical with good results from activity modification and muscle stretching. When nonoperative treatment fails, both open and endoscopic surgery may be considered. In general, an endoscopic approach offers decreased morbidity and quicker return to sport. The endoscopic approach is technically demanding, and surgeons should be comfortable with soft tissue endoscopy techniques before approaching release of the AIN in this manner. Good results can be expected from either approach with proper selection of surgical candidates. Patients can be anticipated to make a full return to sports.
KeywordsAIN Pronator syndrome Median nerve Compression Lacertus fibrosus
Conflicts of Interest: John Lubahn has no conflicts of interest to disclose; Nicolai Baecher has no conflicts of interest to disclose.
Preoperative exam demonstrating weakness of the FPL and FDP to the index, as well as weakness to the FCR (MP4 69120 kb)
Demonstration of a completed open AIN release with concomitant release of the lacertus fibrosus (MP4 36530 kb)
Endoscopic release of the pronator teres (WMV 17042 kb)
Endoscopic release of the fibrous FDS arch. Part 1 (WMV 13159 kb)
Endoscopic release of the fibrous FDS arch. Part 2 (WMV 21206 kb)
Postoperative demonstration of FDS and FPL strength after open AIN release compared to symptomatic contralateral side (MP4 8103 kb)
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