Ulnar Neuropathy Treatment & Management

  • Author: Charles F Guardia III, MD; Chief Editor: Nicholas Lorenzo, MD   more...
 
Updated: May 18, 2011
 

Medical Care

Medical and other nonsurgical treatments can provide significant help in cases of ulnar neuropathy. Vasculitic and metabolic causes can be evaluated and diagnosed to facilitate treatment of the underlying condition.

The physician can address pain or other sensory symptoms using trials of various classes of pain medications including:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs), many classes
  • Tricyclic (and related) antidepressants
  • Anticonvulsants
  • Narcotics (generally considered to be a last resort)

Occupational therapy and work hardening programs are also beneficial. Therapists may use and design splints to restrict the range of joint motion and cushions to ameliorate the effects of pressure.[64]

Use of a night splint is a common occupational or physical therapy technique that aims to limit the flexion and extension of the elbow at night. This has shown some efficacy in clinical trials.[65] Therapists also use nerve gliding, sliding, or tensioning exercises which seek to promote smoother movements of the nerve within the cubital tunnel and to reduce adhesions and other causes of physical nerve compression.[66] A randomized, controlled study of conservative methods to treat mild and moderate ulnar neuropathy at the elbow indicated that simply giving patients information about how to avoid injuring the ulnar nerve by avoiding or reducing movements or positions that compromise the nerve produced significant symptomatic improvement. Interestingly, adding splinting or nerve-gliding treatments to the program of providing information did not add a significant additional benefit.[67, 68]

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Surgical Care

If nonsurgical methods fail, and in patients with severe and/or progressive weakness/atrophy, specific surgical techniques such as medial epicondylectomy, simple release of the flexor carpi ulnaris aponeurosis, and anterior transposition of the nerve are often beneficial in cases of ulnar neuropathy at the elbow.[69] Entrapments in Guyon canal are also amenable to surgical treatment.[2]

A Cochrane review presented results of 2 meta-analyses of 5 randomized, controlled clinical trials of surgical treatments for idiopathic ulnar neuropathy at the elbow.[67] Four of the studies addressed simple decompression compared with decompression plus transposition.[70, 71, 72, 73] These studies found no significant difference between simple decompression of the nerve and decompression with either submuscular or subcutaneous transposition. This was true both for clinical outcomes and neurophysiological outcomes (ie, nerve conduction and EMG).

One difference between the two approaches was that decompression with transposition produced more superficial and deep wound infections.[67] Two additional meta-analyses, using somewhat different meta-analytic methods, have also concluded that they can find no significant differences between the outcomes of simple decompression compared with decompression plus transposition.[74, 75] However, one of these studies, detected a trend in favor of decompression plus transposition, and the authors opined that perhaps a more highly powered study could detect a difference.[75]

The Cochrane review also examined one study that compared epicondylectomy with anterior transposition and concluded that no significant differences could be found in either clinical or neurophysiological outcomes.[67] Interestingly, patient satisfaction was higher in patients treated with epicondylectomy.[76]

Surgery is also valuable for correction or stabilization of traumatic injuries, resection of masses/cysts, and sectioning of fibrous bands.

Much more detail on the surgical approaches to these problems may be found in Ulnar Nerve Entrapment[14] and Cubital Tunnel Syndrome.[77]

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Consultations

Depending upon etiology, symptoms, and signs, referral to a neurosurgeon, hand surgeon, pain specialist, internist, physiatrist, rheumatologist, occupational therapist, and/or alternative medicine specialist may be appropriate.

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Contributor Information and Disclosures
Author

Charles F Guardia III, MD  Resident Physician, Department of Neurology, Dartmouth Hitchcock Medical Center

Charles F Guardia III, MD is a member of the following medical societies: American Academy of Neurology, American Medical Association, and Radiological Society of North America

Disclosure: Nothing to disclose.

Coauthor(s)

Stephen A Berman, MD, PhD, MBA  Professor of Neurology, University of Central Florida College of Medicine

Stephen A Berman, MD, PhD, MBA is a member of the following medical societies: Alpha Omega Alpha, American Academy of Neurology, and Phi Beta Kappa

Disclosure: Nothing to disclose.

Christina J Azevedo MD  Staff Physician, Department of Neurology, Dartmouth-Hitchcock Medical Center

Christina J Azevedo MD is a member of the following medical societies: American Academy of Neurology

Disclosure: Nothing to disclose.

Specialty Editor Board

Paul E Barkhaus, MD  Professor, Department of Neurology, Medical College of Wisconsin; Director of Neuromuscular Diseases, Milwaukee Veterans Affairs Medical Center

Paul E Barkhaus, MD is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, and American Neurological Association

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD  Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: eMedicine Salary Employment

Neil A Busis, MD  Chief, Division of Neurology, Department of Medicine, Head, Clinical Neurophysiology Laboratory, University of Pittsburgh Medical Center-Shadyside

Neil A Busis, MD is a member of the following medical societies: American Academy of Neurology and American Association of Neuromuscular and Electrodiagnostic Medicine

Disclosure: Nothing to disclose.

Selim R Benbadis, MD  Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, Tampa General Hospital, University of South Florida College of Medicine

Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association

Disclosure: UCB Pharma Honoraria Speaking, consulting; Lundbeck Honoraria Speaking, consulting; Cyberonics Honoraria Speaking, consulting; Glaxo Smith Kline Honoraria Speaking, consulting; Pfizer Honoraria Speaking, consulting; Sleepmed/DigiTrace Honoraria Speaking, consulting

Chief Editor

Nicholas Lorenzo, MD  Chief Editor, eMedicine Neurology; Consulting Staff, Neurology Specialists and Consultants

Nicholas Lorenzo, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Neurology, and American College of Physician Executives

Disclosure: Nothing to disclose.

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This is a schematic diagram of the elbow region. The 5 main sites as given by Posner are labeled 1-5. Other sites and structures are also named. The main regions of interest are circled with pastel colored arrows. Sites 2 and 3 are close together and distinguishing them by EMG and nerve conduction studies is not possible. The term ulnar groove or retrocondylar groove are used to describe this location.
This diagram shows the ulnar nerve distal to the elbow region. The dorsal ulnar cutaneous nerve (lavender) branches off the main trunk (blue). Although the course is not followed in detail after that, the lavender region on the sensory dermatome diagram shows where this sensory nerve innervates the skin. Similarly, the palmar cutaneous sensory nerve (yellow) branches off to innervate the skin area depicted in yellow. The superficial terminal branch is mostly sensory (see green colored skin on palmar surface), though it also gives a branch to the palmaris brevis muscle. The deep terminal branch has no corresponding skin area because it is solely motor innervating the muscles shown, as well as some others not explicitly depicted. Of course the nerve could be pinched or injured anywhere, but the sites listed with Roman numerals I-IV are the relatively common sites.
An example of the inching technique used to isolate conduction block in the left ulnar nerve. Note the significant amplitude drop at the 305-mm distance that correlates with a position 2 cm above the medial epicondyle. This is an example of supracondylar block. Image courtesy of AS Lorenzo, MD.
The normal median and ulnar pattern are compared with that of the 3 commonly recognized types of the Martin-Gruber anomaly.
The first 3 traces correspond to the ulnar compound muscle action potential (CMAP) amplitude while recording at the abductor digitorum quinti (ADQ) and stimulating at the wrist, below the elbow, and above the elbow, respectively. The fourth trace corresponds to stimulation of the median nerve at the elbow while recording at ADQ. Though CMAP amplitude is reduced markedly above the elbow, this is compensated by adding the response seen after stimulating the median nerve; this represents the Martin-Gruber anastomosis.
The first 3 traces correspond to stimulation of the ulnar nerve while recording at the first dorsal interosseous (FDI) muscle at the wrist, below the elbow, and above the elbow, respectively. The fourth trace corresponds to stimulation of the median nerve at the elbow while recording at FDI. This represents the Martin-Gruber anastomosis.
In people with the Martin-Gruber anomaly who do not otherwise have significant neuropathy or nerve compressions, here is what happens when the relevant nerves are stimulated. Median stimulation: Stimulation at the elbow yields a larger compound muscle action potential (CMAP) at the hypothenar muscles, the first dorsal interosseus (FDI), or the thenar muscles (or a combination of these) than does stimulation at the wrist. Ulnar stimulation: Stimulation at the wrist yields a larger CMAP at the hypothenar muscles, the FDI, or the thenar muscles (or a combination of these) than does stimulation at the elbow. Larger and smaller generally means a difference of 1.0 millivolt in amplitude or more.
The Riche-Cannieu anastomosis is a communication between the recurrent branch of median nerve and deep branch of ulnar nerve in the hand. Although it is present in 77% of hands, the extent to which it makes a detectable physiological difference is quite variable. In many hands it seems to contribute little and it does not affect the diagnostic findings at all. Probably the most common effect of the anomaly is to give an ulnar innervation to some muscles that are usually innervated by the median nerve and/or vice versa. The most extreme version of this is the very rare all ulnar hand. Two examples of the confusion this might cause are (1) a median lesion could cause denervation in a typical ulnar muscle such as the adductor digiti minimi (ADM, also called adductor digiti quinti [ADQ]) or the first dorsal interosseus and (2) an ulnar lesion could cause denervation in typically median muscles such as the flexor pollicis brevis (FPB) or the abductor pollicis brevis (APB).
Table 1. Martin-Gruber Anastomosis
TypeAnatomyMost Characteristic FindingConfirmationAdditional VerificationClinical Confusion
ICrossover fibers innervate hypothenar musclesUlnar stimulation at wrist produces larger hypothenar CMAP than stimulation at elbow.Stimulation of median nerve at elbow produces response at hypothenar muscles.Hypothenar CMAP from ulnar stimulation at wrist = Hypothenar CMAP from ulnar stimulation at elbow, plus hypothenar CMAP from median stimulation at elbow Smaller response from proximal stimulation could be mistaken for conduction block.
IICrossover fibers innervate the FDI.Ulnar stimulation at wrist produces larger FDI CMAP than stimulation at elbow.Stimulation of median nerve at elbow produces response at FDI.FDI CMAP from ulnar stimulation at wrist = FDI CMAP from ulnar stimulation at elbow plus FDI CMAP from median stimulation at elbow. Usually none because FDI is not usually a recording site. If it is used, conduction block could be suspected as in type I.
IIICrossover fibers innervate thenar muscles (typically ADP and FPB).Elbow stimulation of median nerve produces greater thenar response than does wrist stimulation.Ulnar stimulation produces thenar CMAP with initial positive deflection. It is higher with wrist stimulation than with elbow stimulation. For thenar CMAP amplitudes, median elbow stimulation amp = median wrist stimulation amp plus ulnar wrist stimulation amp – ulnar elbow stimulation amp Can complicate median nerve studies, especially involving carpal tunnel syndrome.
Abbreviations: CMAP: Compound motor (or muscle) action potential



FDI: First dorsal interosseus



ADP: Adductor pollicis



FPB: Flexor pollicis brevis



Median stimulation: Stimulation at the elbow yields a larger CMAP at the hypothenar muscles, the FDI, or the thenar muscles (or sometimes in a combination of these) than does stimulation at the wrist.



Ulnar stimulation: Stimulation at the wrist yields a larger CMAP at the hypothenar muscles, the FDI, or the thenar muscles (or sometimes in a combination of these) than does stimulation at the elbow.



Note: Larger and smaller generally means a difference of 1 millivolt in amplitude or more.



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