A painless complete abdominal wall palsy with groin and thigh paresthesiae related to traffic accident injury.

INTRODUCTION: No case of complete unilateral abdominal wall palsy, occurring after a traffic accident, was found in the literature data. We report one case. CASE REPORT: A 32-year-old woman was treated for a large abdominal hernia by mesh prosthesis nine years after a traffic accident injury. Surgery led to an iatrogenic lesion of the right lateral femoral cutaneous nerve (LFCN). During the electrodiagnostic examination for the LFCN lesion, abdominal wall palsy was diagnosed. Analysis of the patient's history and clinical, electrophysiological, and imaging data revealed that this abdominal wall palsy was related to a tear of the T10 to L2 anterior roots, plexus or nerves, a consequence of the violent deceleration during the car crash. CONCLUSION: This report highlights the importance of clinical examination, electrodiagnosis and imaging in diagnosing abdominal wall palsy.

Sonography and electrodiagnosis in carpal tunnel syndrome diagnosis, an analysis of the literature.

We present a review of the international literature concerning sonography for the diagnosis of carpal tunnel syndrome (CTS). Analysis of the results and comparison with electrodiagnostic data provide a sensible albeit personal view on the relevance of sonography and whether it competes or is complementary to electrodiagnosis (EDX). Although EDX is considered as the gold standard for CTS diagnosis, one author chose surgical results to define CTS. The normal and threshold mean values for sonography are particularly variable from one study to another. The standard deviation (S.D.), when compared to mean values, makes normal and abnormal data overlap considerably and produces many false negatives when the specificity is high, and many false positives when the sensitivity is high. In fact, sonography is non-interpretable in only 10 to 15% of the population, and it affirms the median nerve lesion at the wrist in 55% of cases when EDX does it in more than 90% with common tests. Further more the specificity of sonography leads to a false positive diagnosis in 1 case out of 5 versus 1 out of 40 with EDX. The main conclusion is that there is no competition but rather a complementarity between sonography and EDX: sonography is certainly an efficient imaging technique but cannot replace proper EDX performed for upper limb paresthesiae. Namely, sonography can answer only one out of the 8 questions a complete EDX answer: Are sonographic images compatible with a median nerve lesion at the wrist? The answer to this solely question can be obtain with a partial EDX using a single conduction test (motor or sensitive), then duration and cost will be comparable to sonography but will be both more sensitive and specific. Finally, one must kept in mind that the final aim of all examinations in CTS is to determine the cause(s) of upper limb paresthesiae, not simply if there is a median nerve lesion at wrist or not.

[Entrapment neuropathies involving the ulnar nerve at the wrist (and into the hand) and the peroneal nerve]. / Neuropathies compressives du nerf ulnaire au poignet (et dans la main) et du nerf fibulaire commun. Données récentes.

We report our experience with patients who underwent surgery for entrapment neuropathies involving the ulnar nerve at the wrist and into the hand and the peroneal nerve. For the ulnar nerve, the cause of the lesion was identified in all patients, generally a cyst which had developed in the Guyon canal. The patients usually recovered completely. For the peroneal nerve, there was a wide variety of causes, with mucoid cysts frequently involved. Recovery was often incomplete, because of the very marked initial axonal damage. We emphasized the need for rapid diagnosis and surgical treatment.

The long thoracic nerve conduction study revisited in 2006.

OBJECTIVE: To compare the reliability and feasibility of recording long thoracic nerve (LTN) conductions either with surface or needle electrodes. METHODS: The nerve conduction studies were carried out bilaterally on 40 control subjects. The LTN was first stimulated at the axilla and recorded with surface electrodes located on the 7th or 8th digitations of the serratus anterior (SA), then stimulated at Erb's point and recorded with a needle inserted in the 6th or 7th digitations of the SA. For each method, the latency and amplitude of the motor action potential were recorded. RESULTS: Responses were recorded on both sides for each patient. With surface recording, the mean latency was 2.2 +/- 0.30 ms, and the mean amplitude was 5.3 +/- 2.4 mV. With needle recording, the mean latency was 3.65 +/- 0.45 ms, and the mean amplitude was 8.95 +/- 4 mV. CONCLUSIONS: This study demonstrates that both techniques are reliable, feasible, and correlate well. SIGNIFICANCE: Our study shows surface recording of nerve conduction should be favored because it is non-traumatic, less uncomfortable for the patient, and less prone to pitfalls. Nevertheless, in pathological cases, both techniques should be used at initial and follow-up examinations in order to better assess axonal loss and nerve conduction impairment.

Frequency of neurogenic thoracic outlet syndrome in patients with definite carpal tunnel syndrome: an electrophysiological evaluation in 100 women.

OBJECTIVE: The aim of this work was to evaluate the frequency of lower brachial plexus lesions as true neurogenic thoracic outlet syndrome (NTOS) in women with carpal tunnel syndrome (CTS). METHODS: This was a prospective and descriptive study. The CTS was clinically and electrodiagnostically defined in each patient. The conduction of ulnar and medial antebrachial cutaneous nerves (MABCN) was bilaterally studied to evaluate the function of lower brachial plexus. One hundred women with 176 median nerve lesions at wrist were studied. Patients with ulnar nerve lesion at elbow or wrist were excluded. The sensory nerve action potential (SNAP) of ulnar nerve was abnormal when the interside amplitude ratio was greater than 1.66 or when its amplitude was smaller than 8 microV. The SNAP of MABCN was abnormal when the interside amplitude ratio was greater than 1.66 with both techniques (antidromic and orthodromic) or when its amplitude was smaller than 8 and 6 microV for non-obese patients, respectively, less and more than 60 years old. RESULTS: The mean SNAP amplitude of ulnar and MABC nerves was normal compared with control subjects, and none of the 100 women with CTS had an abnormal interside amplitude ratio for one or both nerves. In 7-10 cases, all of which were either obese or elderly patients, SNAP amplitude of MABCN was decreased, but the interside amplitude ratio remained normal. CONCLUSIONS: On the basis of tests considered quite sensitive (70%) and specific (100%), the occurrence of true NTOS is lower than 1/100 in woman with definite CTS. SIGNIFICANCE: These results demonstrate that there is no appreciable link between CTS and true NTOS. There is no need for the systematic MABCN testing had in CTS patients.

Symptoms of thoracic outlet syndrome in women with carpal tunnel syndrome.

OBJECTIVE: To evaluate the frequency of symptoms and signs suggestive of thoracic outlet syndrome (TOS) in women aged 60 years or less, with unambiguous carpal tunnel syndrome (CTS). METHODS: The CTS was clinically and electrodiagnostically defined in 100 upper limbs. Clinical and electrophysiological symptoms and signs suggestive of TOS, true neurogenic TOS (NTOS) and disputed NTOS were tested in each upper limb. The 100 idiopathic median nerve lesions at the wrist occurred in 61 successive and unselected women. Women with ulnar nerve entrapment, root lesions and polyneuropathies were excluded. The main outcome measures were clinical symptoms and signs suggestive of TOS and NTOS as electrodiagnostic evaluation of the lower brachial plexus. RESULTS: In the 100 upper limbs with definite CTS, no major symptoms and signs suggestive of TOS and NTOS were found. On the contrary, moderate and mild clinical symptoms and signs suggestive of disputed NTOS were frequently found, even if no electrodiagnostically definite major or minor lower brachial plexus lesion was found. CONCLUSIONS: This study demonstrates the low specificity of clinical symptoms and signs suggestive of disputed NTOS, as they were frequently found in women with unselected and unambiguous CTS, despite no patients had definite lower brachial plexus lesion. SIGNIFICANCE: Our study shows why CTS can easily be misdiagnosed as disputed NTOS, and stresses the importance of systematic electrodiagnosis with median, ulnar, and medial antebrachial cutaneous nerve conduction studies, in order to rule out CTS, ulnar nerve, root lesion, and to establish lower brachial plexus lesion before treating NTOS.

[Idiopathic lumbosacral plexopathy]. / Plexopathie lombo-sacrée idiopathique.

INTRODUCTION: Lumbosacral plexopathy is the equivalent in the lower limbs of neuralgic amyotrophy (also known as Parsonage-Turner syndrome) in the upper limbs. It is well-known in patients with diabetes mellitus, when it is known as Bruns-Garland syndrome. CASE: We report the case of a 47-year-old woman who developed a unilateral neuropathy of the leg, neither radicular nor truncal in origin. The slow continuous improvement was not affected by any of the treatments administered. DISCUSSION: Lumbosacral plexopathy is characterized by intense pain in one or both legs, associated with motor and sensory deficits. Recovery is usually slow (6 to 36 months) and often incomplete. The electrodiagnostic examination shows important acute motor and sensory axonal loss, characterized by denervation and low-amplitude sensory action potential. Treatment generally combines analgesics with narcotic agents, neuropathic pain medication, short-term corticosteroids, and rehabilitation. In the most severe cases, long-term corticosteroids and other immunosuppressive agents may be required. This diagnosis cannot be reached until all other radicular, plexal and truncal origins have been ruled out.

Ulnar nerve lesion at the wrist and sport: A report of 8 cases compared with 45 non-sport cases.

OBJECTIVE: Reporting clinical and electrodiagnostic characteristics of sport-related ulnar neuropathies at the wrist. PATIENTS AND METHODS: Eight sport-related and 45 non-sport-related cases from 53 ulnar neuropathies at the wrist cases over 14 years. RESULTS: Sport-related ulnar neuropathies at the wrist cases were due to cycling (5 cases), kayaking (2 cases), and big-game fishing (1 case). No patient had sensory complaints in ulnar digits, and all had motor impairment. Conduction across the wrist with recording on the first dorsal interosseous muscle was impaired in all cases, with conduction block in 5. Two cyclists showed bilateral ulnar neuropathies at the wrist. All cases recovered within 2 to 6 months with sport discontinuation. Distal lesions of the deep motor branch were more frequent in sport- than non-sport-related cases. CONCLUSIONS: The 8 sport-related ulnar neuropathies at the wrist cases involved the deep motor branch. Conduction study to the first dorsal interosseous muscle across the wrist is the key to electrodiagnostics. Bilateral cases in cyclists does not require wrist imaging.

Medial antebrachial cutaneous nerve conduction study, a new tool to demonstrate mild lower brachial plexus lesions. A report of 16 cases.

OBJECTIVE: This was to demonstrate the ability to electrodiagnosed mild lower brachial plexus lesion only through abnormal medial antebrachial cutaneous nerve (MABCN) conduction study. METHODS: We report 16 cases of unilateral, atypical pains and paresthesias of the upper limbs without motor deficit or atrophy. Patients were referred as carpal tunnel syndrome in 12 cases. All patients had needle examination of the impaired upper limb from C5 to T1. Motor and sensory conductions of median and ulnar nerves were bilaterally studied. MABCN was antidromically (16 cases) and orthodromically (9 cases) studied at the elbow in the both sides. MABCN abnormality was defined by an interside amplitude ratio of the sensory nerve action potential equal or greater than 2 (mean + 3 SD). RESULTS: No patient had a definitive and accurate diagnosis, before MABCN abnormality determination. MABCN testing was abnormal in all the 16 cases with a mean interside amplitude ratio of 7.2 (mean + 25 SD), when all other motor and sensory nerve conductions were normal. All except four patients showed normal needle examination from C5 to T1. In 5 cases, an obvious cause (traumatic and neoplastic) explained the mild lower brachial plexus lesion. In 2 cases, a mild neurogenic thoracic outlet syndrome (NTOS) was confirmed by surgical findings. In the 9 other cases, the mild lower brachial plexus lesion defined by MABCN findings, was without cause and was considered as a mild NTOS. CONCLUSIONS AND SIGNIFICANCE: These 16 cases, support a new electrodiagnostic pattern to define a mild lower brachial plexus lesion: comparatively low or low MABCN SNAP amplitude, normal median and ulnar SNAP/Compound motor action potential amplitudes and normal or slightly reduced interference pattern in some C8-T1 innervated muscles. This pattern can be found in patients with 'carpal tunnel syndrome like' symptoms who have normal electro-diagnostic examination, or in patients with clinical features suggesting a lower brachial plexus lesion.

[Study of the proximal conduction of the arms using SEP and MEP]. / Etude de la conduction proximale du membre supérieur par PES et PEM.

The proximal conduction of the upper limb has been studied with the somatosensory evoked potentials (SEP) and motor evoked potentials (MEP) in 40 controls which provided normal data. The SEP allowed the sensory conduction study of the Erb/C7 segment with N9/N13 delay determination after the median nerve stimulation at the wrist, and after the ulnar nerve stimulation at the wrist (20 cases) or above the elbow (20 cases). The N9/N13 delay was 3.24 ms +/- 0.35 for the median nerve, 3.30 ms +/- 0.52 for the ulnar nerve after stimulation at the wrist and 3.30 ms +/- 0.40 after stimulation at the elbow. The Erb point potential amplitude after ulnar nerve stimulation at the elbow was always greater than after the median nerve stimulation at the wrist: 13.2 microV versus 8.8 microV. The MEP allowed the C6/axilla motor conduction study. The recording was performed on the adductor digiti quinti. The proximal motor conduction velocity was 74 m/s +/- 8 (mini 60). The conduction delay was then 3.02 ms +/- 0.3. A constant amplitude loss was observed between the axilla and the cervical spine; it was never greater than 30% in controls. Allthings considered both methods provided very complementary data on the proximal nerve conduction of the upper limb at the brachial plexus. The conduction delay in the brachial plexus was around 3 ms and was very similar to the distal motor and sensory latencies of the median nerve at the wrist. Motor conduction blocks of more than 30% and 1 ms increament of the conduction delay were regarded as pathological.

[The centimeter test: diagnostic test for beginning carpal tunnel syndrome]. / Le test centimétrique: test diagnostique du syndrome du canal carpien débutant.

This study, in 13 control subjects, assesses the normal value of the centimeter conduction delay (CCD). The mean CCD is 0.184 ms, the maximum CCD is less than 0.40 ms and the ratio between maximum and normal CCD never exceeds 2. In 47 patients with clinical features of carpal tunnel syndrome and normal classical EMG data, the centimeter test selected two groups. The first consists in 32 patients with a pathological maximum CCD varying from 0.36 to 1.10 ms and a maximum to normal CCD mean ratio of 3.75. The second group consists in 15 patients with a maximum CCD between 0.21 and 0.39 ms and a maximum to normal CCD mean ratio of 1.52.

Treatment of ulnar nerve palsy at the elbow with a night splint.

Twenty-two patients with ulnar nerve palsy at the elbow, confirmed by electromyography, were treated by a night splint which prevented flexion of the elbow beyond 60 degrees. The splint was worn all night regularly for at least six months. At a mean follow-up of 11.3 months, 17 patients had clinical and electromyographic assessment and five were contacted by telephone. There was improvement in the symptoms in every patient, including three who had failed to respond to surgical decompression. There was electromyographic improvement in 16 of the 17 patients re-examined at follow-up. The mean improvement in motor nerve conduction velocity was 6.5 m/s and in sensory nerve conduction velocity 9.5 m/s. The efficacy of this treatment suggests that nocturnal elbow flexion is an important cause of ulnar nerve lesions at the elbow.

Anterior interosseous nerve lesions. Clinical and electrophysiological features.

Lesions of the anterior interosseous nerve in the forearm are rare and often misdiagnosed as tendon injuries. A consecutive series of 13 patients with this condition referred for electrodiagnosis is reviewed. Only three had originally a correct clinical diagnosis and three were initially considered to have tendon ruptures. Five cases were of mechanical origin and seven due to 'neuritis'. All showed electrophysiological abnormalities, most commonly involving the pronator quadratus. Late spontaneous recovery was common, and only one case had surgical exploration.

Ulnar nerve compression at the wrist by a synovial cyst successfully treated with percutaneous puncture and corticosteroid injection.

A case of ulnar nerve palsy due to a conduction block in the deep motor branch at the wrist is reported. The cause was a rapidly growing synovial cyst. Ultrasonography and computed tomography were performed to determine the exact location of the cyst, which was punctured and injected with corticosteroid. Function promptly returned to normal after this procedure.

Sensitivity of the various tests for the diagnosis of carpal tunnel syndrome.

The electrophysiological results of a prospective study of 150 successive cases of carpal tunnel syndrome in 96 patients are reported to evaluate the sensitivity of nine different electrophysiological tests and thresholds for the diagnosis of carpal tunnel syndrome. The distal motor latency was > 5 ms in 35% of cases and > or = 4 ms in 55% of cases. The distal sensory latency from the PIP joint of the middle finger was up to 3.4 ms in 61% of cases. The middle finger orthodromic conduction velocity (14 cm) was < or = 45 m/s in 66% of cases and the orthodromic conduction velocity after palmar stimulation (8 cm) was < or = 45 m/s in 76%. The remaining 24% of cases were assessed by special tests such as specific median-ulnar latency difference (21%), and the centimetric test was altered in all. Highly sensitive tests are required to assess or exclude the diagnosis in one quarter of cases of carpal tunnel syndrome. Although the specific median-ulnar latency difference is the easiest test to perform, the centimetric test is the most valuable for the assessment of the mildest forms of carpal tunnel syndrome.

Nerve conduction studies after treatment for carpal tunnel syndrome.

125 cases of carpal tunnel syndrome confirmed electrophysiologically were the subject of longitudinal nerve conduction studies to assess spontaneous improvement and effect of treatment. 36 cases showed a slowly progressive deterioration which became statistically significant only on lengthy follow-up; analysis of interval tests in these cases revealed that definite improvement or rapid worsening can occur in the interim. The 56 cases studied after local corticosteroid injections showed a statistically significant improvement at one month followed by an overall progressive return to the previous abnormal values in six to 12 months, indicating only slight and temporary alteration in the natural progression of the conduction deficit. The 33 cases which underwent surgical release of the median nerve were shown to have obvious and often rapid improvement, which was sustained for at least one year after surgery.

Pregnancy-related carpal tunnel syndrome.

Clinical and electrophysiological features were studied in 52 cases of carpal tunnel syndrome (CTS) associated with 30 pregnancies. The duration of symptoms was less than 3 months before electrodiagnosis was performed. This study revealed a higher incidence of persistent, painful diurnal symptoms in pregnancy-related CTS (PRCTS) than in idiopathic CTS. PRCTS usually occurs for the first time (de novo) (24/30 cases), in primigravidas (15 cases) as well as multigravidas. The onset of symptoms was in the first or second trimester in 11 women, the third trimester in 12 women, or the post-partum period in seven women. Nerve conduction studies demonstrated evidence of an acute median nerve lesion at the wrist with motor and/or sensory conduction blocks in 20/30 women and severe denervation signs in five women.

Tinel's sign in the diagnosis of carpal tunnel syndrome.

A positive Tinel's sign was found in 63% of patients with electrophysiologically proved carpal tunnel syndrome. However, Tinel's sign was also positive in 45% of control patients. It is therefore concluded that the sign is of no diagnostic value in individual patients with suspected carpal tunnel syndrome.

Phalen's test in the diagnosis of carpal tunnel syndrome.

The wrist flexion test of Phalen has been studied in 127 patients with carpal tunnel syndrome and 20 control subjects, all of whom also had nerve conduction studies. There was a statistically significant relationship between the severity of electrical changes and the probability of a positive Phalen's test. However 34% of patients had a negative test and 20% of control subjects a positive one.

[Sural nerve neuropathy (external saphenous) linked to a disease of the small saphenous vein. Apropos of 5 cases]. / Atteinte du nerf sural (saphène externe) liée à une pathologie de la veine petite saphène. A propos de 5 cas.

Five cases of sural nerve lesion linked to small saphenous vein pathology are reported. They were due to vein stripping (4 cases) and to thrombophlebitis (1 case). The diagnosis was especially delayed in the first 4 cases, as this pathological field is quite unknown. In all the cases, only electrodiagnosis allowed to assess the diagnosis and medical care was sufficient to control the pain of these patients.