Pronator Syndrome and Anterior Interosseous Nerve Syndrome

The Journal of the American Academy of Orthopaedic Surgeons (Impact Factor: 2.53). 05/2013; 21(5):268-75. DOI: 10.5435/JAAOS-21-05-268
Source: PubMed


Dysfunction of the median nerve at the elbow or proximal forearm can characterize two distinct clinical entities: pronator syndrome (PS) or anterior interosseous nerve (AIN) syndrome. PS is characterized by vague volar forearm pain, with median nerve paresthesias and minimal motor findings. AIN syndrome is a pure motor palsy of any or all of the muscles innervated by that nerve: the flexor pollicis longus, the flexor digitorum profundus of the index and middle fingers, and the pronator quadratus. The sites of anatomic compression are essentially the same for both disorders. Typically, the findings of electrodiagnostic studies are normal in patients with PS and abnormal in those with AIN syndrome. PS is a controversial diagnosis and is typically treated nonsurgically. AIN syndrome is increasingly thought to be neuritis and it often resolves spontaneously following prolonged observation. Surgical indications for nerve decompression include persistent symptoms for >6 months in patients with PS or for a minimum of 12 months with no signs of motor improvement in those with AIN syndrome.

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    • "known as pronator syndrome (PS) and under the ligament of Struthers [9] [10] [11] [12] [13]. Median nerve entrapment under ligament of Struthers is very rare [1]. "
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    ABSTRACT: Aim of the work: The aim of the present study was to detect subclinical pronator syndrome (PS) in patients with carpal tunnel syndrome (CTS) with the utility of the anterior interosseous/median (AIM) score. Patients and methods: The present study included 90 clinically diagnosed CTS hands and 60 asymptomatic hands of healthy volunteers as a control group. Clinical examination was done for all patients. The following tests were done: (1) Sensory nerve conduction studies: median and ulnar nerves; (2) Motor nerve conduction studies: median and ulnar nerves as well as the anterior interosseous nerve recording the pronator quadratus muscle with calculation of the AIM score. AIM score is a ratio of the antecubital motor latency of the anterior interosseous nerve to that of the median nerve. Results: There were 71 CTS hands (78.9%) with a median distal latency (DL) exceeding the reference value and the AIM score was decreased in 63 (70%) of them. Eight hands (8.9%) had a prolonged median DL associated with an AIM score within the reference range raising the probability of having PS. Five (5.6%) of these eight hands had electrophysiological findings in consistency with an established PS. The sensitivity of AIM for the concomitant detection of PS with CTS was 100% and the specificity 95.4%. None of the controls had PS. Conclusions: Subclinical PS is found in CTS patients and could be searched for electrophysiologically in those patients with evidence of moderate to severe degrees of CTS and the AIM score is useful in this aspect.
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    ABSTRACT: The supracondylar process is a congenital bone projection on the distal anteromedial humerus often associated with a ligament of Struthers, a fibrous connection between the process and medial epicondyle. It is largely asymptomatic and only on rare occasions presents with neurovascular compression resulting in a supracondylar process syndrome. This case report describes a 28-year-old woman with supracondylar process syndrome, and our management. The topic is further explored with a literature review of 43 reported cases. Analysis of the case reports indicates that isolated median nerve injuries are the most common. Other presentations such as fractures, vascular compromise, and ulnar nerve involvement are less frequent.
    No preview · Article · Jun 2014 · The Journal Of Hand Surgery
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    ABSTRACT: This review discusses key diagnostic points and treatment guidelines for compression neuropathies of the wrist, forearm, and elbow. Recent treatment progress is reviewed, controversies are highlighted, and consensus is summarized. Limited or mini-open releases and endoscopic carpal tunnel releases are considered equally safe and efficient. Both methods are currently mainstays of surgical treatment.
    No preview · Article · Jul 2014 · Clinics in Plastic Surgery
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