Abstract
INTRODUCTION:: Different hypotheses have been proposed for the pathophysiology of anterior interosseous nerve (AIN) palsy: compression, fascicular constriction or nerve inflammation (Parsonage-Turner Syndrome). We hypothesized that critical reinterpretation of electrodiagnostic studies (EDX) and MRIs of patients with a diagnosis of AIN palsy could provide insight into the pathophysiology and treatment. MATERIALS AND METHODS:: A retrospective review was performed of all patients with a diagnosis of non-traumatic AIN palsy and an upper extremity MRI performed at our institution. The original EDX and MRI reports were re-interpreted by a neuromuscular neurologist and musculoskeletal radiologist respectively, both blinded to our hypothesis. RESULTS:: One hundred and twenty-three patients were identified with non-traumatic AIN palsy. Of these, 16 patients met the inclusion criteria as having “isolated” AIN palsy. Physical examination revealed weakness in muscles not innervated by the AIN in 5 cases (31%) and EDX abnormalities not related to the AIN were found in 9 cases (60%). The initial MRI report described atrophy in muscles not innervated by the AIN or nerve enlargement different from the AIN in 8 cases (50%). In all cases, reinterpretation of the MRIs demonstrated atrophy in at least one muscle not innervated by the AIN and did not reveal any evidence of compression of the AIN. CONCLUSION:: All patients in our series with presumed isolated AIN palsy had MRI evidence of a more diffuse muscle involvement pattern, without any radiologic signs of nerve compression of the AIN branch itself. These data strongly support an inflammatory pathophysiology.
| Original language | English (US) |
|---|---|
| Journal | Plastic and Reconstructive Surgery |
| DOIs | |
| State | Accepted/In press - Jul 5 2016 |
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ASJC Scopus subject areas
- Surgery
Cite this
Reinterpretation of Electrodiagnostic Studies and MRIs in Patients with Non-Traumatic “Isolated” Anterior Interosseous Nerve Palsy. / Maldonado, Andrés A.; Amrami, Kimberly K.; Mauermann, Michelle M; Spinner, Robert J.
In: Plastic and Reconstructive Surgery, 05.07.2016.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Reinterpretation of Electrodiagnostic Studies and MRIs in Patients with Non-Traumatic “Isolated” Anterior Interosseous Nerve Palsy
AU - Maldonado, Andrés A.
AU - Amrami, Kimberly K.
AU - Mauermann, Michelle M
AU - Spinner, Robert J.
PY - 2016/7/5
Y1 - 2016/7/5
N2 - INTRODUCTION:: Different hypotheses have been proposed for the pathophysiology of anterior interosseous nerve (AIN) palsy: compression, fascicular constriction or nerve inflammation (Parsonage-Turner Syndrome). We hypothesized that critical reinterpretation of electrodiagnostic studies (EDX) and MRIs of patients with a diagnosis of AIN palsy could provide insight into the pathophysiology and treatment. MATERIALS AND METHODS:: A retrospective review was performed of all patients with a diagnosis of non-traumatic AIN palsy and an upper extremity MRI performed at our institution. The original EDX and MRI reports were re-interpreted by a neuromuscular neurologist and musculoskeletal radiologist respectively, both blinded to our hypothesis. RESULTS:: One hundred and twenty-three patients were identified with non-traumatic AIN palsy. Of these, 16 patients met the inclusion criteria as having “isolated” AIN palsy. Physical examination revealed weakness in muscles not innervated by the AIN in 5 cases (31%) and EDX abnormalities not related to the AIN were found in 9 cases (60%). The initial MRI report described atrophy in muscles not innervated by the AIN or nerve enlargement different from the AIN in 8 cases (50%). In all cases, reinterpretation of the MRIs demonstrated atrophy in at least one muscle not innervated by the AIN and did not reveal any evidence of compression of the AIN. CONCLUSION:: All patients in our series with presumed isolated AIN palsy had MRI evidence of a more diffuse muscle involvement pattern, without any radiologic signs of nerve compression of the AIN branch itself. These data strongly support an inflammatory pathophysiology.
AB - INTRODUCTION:: Different hypotheses have been proposed for the pathophysiology of anterior interosseous nerve (AIN) palsy: compression, fascicular constriction or nerve inflammation (Parsonage-Turner Syndrome). We hypothesized that critical reinterpretation of electrodiagnostic studies (EDX) and MRIs of patients with a diagnosis of AIN palsy could provide insight into the pathophysiology and treatment. MATERIALS AND METHODS:: A retrospective review was performed of all patients with a diagnosis of non-traumatic AIN palsy and an upper extremity MRI performed at our institution. The original EDX and MRI reports were re-interpreted by a neuromuscular neurologist and musculoskeletal radiologist respectively, both blinded to our hypothesis. RESULTS:: One hundred and twenty-three patients were identified with non-traumatic AIN palsy. Of these, 16 patients met the inclusion criteria as having “isolated” AIN palsy. Physical examination revealed weakness in muscles not innervated by the AIN in 5 cases (31%) and EDX abnormalities not related to the AIN were found in 9 cases (60%). The initial MRI report described atrophy in muscles not innervated by the AIN or nerve enlargement different from the AIN in 8 cases (50%). In all cases, reinterpretation of the MRIs demonstrated atrophy in at least one muscle not innervated by the AIN and did not reveal any evidence of compression of the AIN. CONCLUSION:: All patients in our series with presumed isolated AIN palsy had MRI evidence of a more diffuse muscle involvement pattern, without any radiologic signs of nerve compression of the AIN branch itself. These data strongly support an inflammatory pathophysiology.
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U2 - 10.1097/PRS.0000000000002689
DO - 10.1097/PRS.0000000000002689
M3 - Article
C2 - 27391838
AN - SCOPUS:84978033561
JO - Plastic and Reconstructive Surgery
JF - Plastic and Reconstructive Surgery
SN - 0032-1052
ER -