Electrodiagnostic Findings in 441 Patients with Ulnar Neuropathy - a Retrospective Study

Abstract

Purpose

Ulnar neuropathy (UN) is the second most common focal neuropathy in the upper extremities. Electrodiagnostic studies (EDx), including nerve conduction study (NCS) and electromyography (EMG), are reliable tools for the diagnosis of ulnar neuropathy. We aimed to retrospectively analyze the medical records of patients diagnosed with ulnar neuropathy in a seven-year period and report our findings.

Patients and methods

In this retrospective study, documents of the patients whose ulnar nerve injury was confirmed through electrodiagnostic study in two departments of Physical Medicine and Rehabilitation were collected and demographic data, subjective complaints of the patient, the cause, and electrodiagnostic findings were extracted from each patient’s file. The following points were specifically evaluated in the electrodiagnostic records; type of injury, location, accompanying injuries, sensory nerve action potentials (SNAP) of the fifth finger, SNAP of dorsal ulnar cutaneous nerve (DUCN), compound muscle action potential (CMAP) of abductor digiti minimi (ADM) muscle, nerve conduction velocity (NCV) across elbow, patterns of muscle involvement, and the severity of insult.

Results

Out of 441 records, 305 (69.2%) were male and 68.1% were non-traumatic. Based on our clinical criteria, the intensity of the injury was mild in most cases. The elbow and forearm were the most involved regions in non-traumatic and traumatic cases respectively. Across elbow nerve conduction velocity showed decreased velocity in 71% of records. In non-traumatic cases, the most affected muscle was ADM (97%) and then FDI (85%).

Conclusion

In focal entrapments such as ulnar neuropathy, electrodiagnostic findings are very helpful in assessing location, severity, and type of injury. If a consensus is achieved for the diagnosis of UN, even retrospective studies can become valuable sources for studying UN.

Keywords:

• ulnar nerve
• electrodiagnostic study
• nerve lesion

Acknowledgements

The authors would like to thank hospital personnel who contributed to this national project.

This article has been extracted from the thesis written by Dr. Parisa Yuseffam in the School of Medicine Shahid Beheshti University of Medical Sciences (Registration No: 424m).

Abbreviations

UN, ulnar neuropathy; EDx, electrodiagnostic studies; NCS, nerve conduction study; EMG, electromyography; NCV, nerve conduction velocity; NAP, sensory nerve action potentials; DUCN, dorsal ulnar cutaneous nerve; CMAP, compound muscle action potential; ADM, abductor digiti minimi; FDP, flexor digitorum profundus; FCU, flexor carpi ulnaris; AP, adductor pollicis; UNE, ulnar neuropathy at the elbow; AAEM, American Association of Electrodiagnostic Medicine; AE, above elbow; BE, below elbow; NTI, non-traumatic injury; TI, traumatic injury; SSNCSs, short-segment nerve conduction studies.

Ethics Approval and Consent to Participate

The data of the research have been employed from hospital records of patients who have signed and stated their consent for using their not-identifying data for the aim of research. The study was approved by ethics committee of Shahid Beheshti University of Medical Sciences, Tehran, Iran

Availability of Data and Materials

The data of the research are based on hospital records that are available as a part of hospital HIS (Health Information System). It should be mentioned that in all Iranian public hospitals, data of patients are electronically recorded.

Author Contributions

Seyed Ahmad Raeissadat has designed and made definition of intellectual content. Leila Bagherzadeh searched the literature. Parisa Youseffam gathered the data and performed statistical analysis. Leila Bagherzadeh and Seyed Ahmad Raeissadat prepared the manuscript. Seyed Mansour Rayegani edited the manuscript. Mohammad Hasan Bahrami and Dariush Eliaspour reviewed and made revision on the manuscript. All authors made substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; gave final approval of the version to be published; and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.