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E B Bodofsky

Publications and source records attributed to E B Bodofsky.

6 recordsLinked to original sources

Age and the severity of carpal tunnel syndrome.

Several studies have shown an increased incidence of Carpal Tunnel Syndrome (CTS) with increasing age, as well as a longer Median sensory latency in older CTS patients. In this study, data was analyzed from 19 patients with bilaterally normal UE EMG/NCS and no symptoms of CTS (38 hands), as well as 18 patients with unilateral CTS and 21 with bilateral CTS (60 hands) to determine the effect of age on the severity of nerve conduction abnormalities associated with CTS. Most of these parameters showed increasing severity with age. Median motor latency rises sharply with age (r = .41, p = .001), and amplitude falls (r = .34, p = .008). Median sensory rises significantly with age in CTS patients (r = .42, p = .001) and amplitude falls (r = .29, p = .022). Furthermore, the (Median-Ulnar) motor and sensory latency differences both rise with age (r = .40, p = .001, and r = .35, p = .004 respectively). This is crucial, for an increase in Median motor or sensory latency with age could represent a similar degree of pathologic slowing superimposed on normally slower conduction with age. However, the sharp rise in the (Median-Ulnar) latency differences (from 2.2 msecs at age 40 to 3.8 msecs at age 70 for motor, and 1.6 msecs to 2.5 msecs for sensory) shows that the compression is more severe with age.

Adult↗

Diagnosing mild Carpal Tunnel Syndrome with interpolation.

Carpal Tunnel Syndrome (CTS) is the most common peripheral nerve entrapment. In the diagnosis of Carpal Tunnel Syndrome, velocity is determined by either measuring the average velocity over a segment by dividing the distance by the difference in latencies. Polynomial interpolation can determine the velocity at any point along a nerve. Applying interpolation techniques correctly classified 58/60 electrophysiologically proven CTS cases (96.7%) and 36/38 normals (94.7%). Of 7 cases with CTS by standard sensory criteria alone, 6 (86%) had abnormal motor conduction using the interpolation technique. This shows that interpolation techniques can improve diagnostic accuracy in CTS. It also indicates that there is motor involvement in most cases of CTS, including a majority of cases previously classified as only sensory involvement.

Carpal Tunnel Syndrome↗

A mathematical model for peripheral nerve conduction velocity.

OBJECTIVE: To derive a mathematical model for peripheral axon geometry, and apply it to the prediction of latencies along a nerve. DESIGN: Retrospective review of data from individuals with bilaterally normal EMG/NCS, those with a diagnosis of carpal tunnel syndrome alone, and data from previous researchers. SETTING: Electrodiagnostic laboratory at a teaching hospital. SUBJECTS: Twenty-two (22) individuals with bilaterally normal EMG/NCS, and 61 hands from 40 individuals with carpal tunnel syndrome. Data from previous researchers was also utilized. RESULTS: Applying an exponentially tapering axon model to normal data yielded a formula for latency (L = kd 0.775) where k is a constant, and d is the distance from the distal end of the nerve. This formula produced a correlation of 0.777 for predicting median distal motor latencies using the proximal latency, and 0.676 for the ulnar nerve. The largest difference between predicted and actual distal latency was 0.48 msecs for the median nerve and 0.60 msecs for the ulnar nerve. This formula correctly classified as abnormal 3 (37.5%) out of 8 carpal tunnel syndrome cases with completely normal motor studies by standard criteria. This formula also agreed well with the data of other researchers, predicting normal distal latencies, F wave latencies, and identifying abnormal data. CONCLUSIONS: A single model for axon geometry based on uniform exponential tapering accurately predicts latencies for many nerves, and can detect subtle neuropathology.

Adult↗

Median nerve compression at the wrist: is it ever unilateral?

OBJECTIVE: Carpal Tunnel Syndrome (CTS) is commonly bilateral, but symptoms and EMG/NCS abnormalities may be seen unilaterally. This study was designed to determine whether there are any subclinical nerve conduction abnormalities on the "uninvolved" side. DESIGN: Statistical analysis of electrodiagnostic data. SETTING: Outpatient academic electrodiagnostic laboratory. PATIENTS: Twenty-two successive patients referred for bilateral upper extremity NCS/EMG with no symptoms or physical signs of CTS and totally normal results, and ten successive patients with an EMG/NCS diagnosis of CTS on one side, and completely normal EMG/NCS on the contralateral side. RESULTS: The median motor and sensory latencies at the wrist were significantly longer in the contralateral "uninvolved" limb than normals (median motor latency 3.75 vs. 3.30 msecs, p = 0.0005, median sensory latency 3.40 vs 3.00 msecs, p = 0.0002). Median sensory amplitude was smaller in the contralateral limb (30.5 uV vs. 41.5 uV, p = 0.0062). The (median-radial) D1 sensory latency difference was greater in the contralateral wrist (0.2 vs. 0.0 msecs, p = 0.0217). The (median-ulnar) sensory latency difference was not significantly increased (0.15 vs. 0.10 msecs, p = 0.2020). CONCLUSIONS: The contralateral limbs of patients with unilateral CTS show significant differences from normals in 4 out of 5 nerve conduction parameters. There is evidence of frequent subclinical median nerve compression in this group.

Carpal Tunnel Syndrome↗

Contraction-induced upper extremity H reflexes: normative values.

OBJECTIVES: To determine the reliability of contraction-induced upper extremity H reflexes; to calculate normal values for latency, amplitude, and side-to-side variation; and to correlate latency to arm length. DESIGN: Case series. SETTING: Electrophysiology laboratory of a tertiary care center. PARTICIPANTS: Twenty-three healthy volunteers (4 men, 19 women), aged 19 to 42. INTERVENTION: Volunteers were tested bilaterally for H reflexes in four to six upper extremity muscles during an isometric contraction. MAIN OUTCOME MEASURES: H reflex onset latency, onset to negative peak amplitude, side-to-side variation, normal ranges, and latency versus arm-length correlation. RESULTS: H reflexes were found at all 264 sites tested. Mean latencies varied from 9.5 to 27 msec. Maximum normal side-to-side variation was 1.5 to 2.7 msec. Maximum normal amplitude ratios (larger to smaller) ranged from 2.06 to 4.80. Abductor pollicis brevis (APB) and abductor digiti minimi (ADM) H reflex latencies were strongly correlated to arm length. Correlation for APB = .64 (p<.0001) and for ADM = .70 (p<.0001). CONCLUSIONS: Contraction-induced upper extremity H reflexes occur consistently in healthy adults, with latencies, amplitudes, and side-to-side variation occurring in predictable ranges.

Adult↗

A sensitive new median-ulnar technique for diagnosing mild Carpal Tunnel Syndrome.

Carpal Tunnel Syndrome (CTS) is easily the most common focal peripheral nerve compression. The primary diagnostic tool is electrodiagnosis, although 13-27% of patients with symptoms and signs of CTS have normal electrodiagnostic results. The goal of this study was to create a more sensitive and specific latency difference criteria without any additional testing beyond the minimum. Statistical theory indicates that this would occur by comparing the latency most sensitive to CTS to the least sensitive latency. Data was evaluated from 68 normal hands, 23 hands of patients with symptoms and signs of CTS but normal standard results, and 88 hands of patients with CTS symptoms and signs of CTS with the diagnosis confirmed with standard criteria. The Median Sensory latency was the most sensitive parameter, while the Ulnar Motor Latency varied least in the presence of CTS, making the (Median Sensory-Ulnar Motor) latency difference the criteria of choice. Setting a cutoff value of 0.8 msecs for this difference correctly classified all normals, and all hands with CTS by standard criteria, and classified as abnormal 19/23 (82%) of hands with symptoms and signs of CTS but negative results by standard criteria. Overall the (Median Sensory-Ulnar Motor) Latency difference is a simple, easy, sensitive and specific test for CTS.

Carpal Tunnel Syndrome↗