Median neuropathy is a term describing the injury to the median nerve along its path from the brachial plexus to the distal forearm. The nerve is most susceptible to injury within the carpal tunnel. The term carpal tunnel syndrome is used to describe median nerve injury at that site, but median neuropathy can occur through numerous other mechanisms, which is why a thorough diagnostic workup is necessary.
Presentation
The clinical presentation of median neuropathy depends on the location where the median nerve is injured. In the vast majority of cases, however, the carpal tunnel is the site where the injury occurs, and the term "carpal tunnel syndrome" is used as a distinct clinical entity to describe the pathophysiological and clinical changes [1]. Several risk factors have been established, such as diabetes mellitus (a significantly higher incidence rate is observed compared to the general population), genetic predisposition, female gender, and profound occupational wrist efforts [1] [2]. Most important symptoms are a pain of the hand (the thumb and the first two and a half fingers are innervated by the median nerve) and the wrist that often wakes patients at night, and is accompanied by paresthesias. Additionally, sensory loss in the abovementioned fingers on the palmar side of the hand and weakness or wasting of the thenar muscles (opponens pollicis, flexor pollicis brevis and abductor pollicis brevis) are signs of severe median nerve injury [1] [2] [3]. The dominant hand is more frequently affected, but a bilateral presentation may be observed as well. [3] [4]. Apart from the carpal tunnel, the antecubital fossa is also an important site where median neuropathy can originate from, with most common causes being the injury during intravenous injection or cannulation, and trauma [4].
Entire Body System
- Pain
It may be a difficult diagnosis to make, as it often presents with arm pain that is diffuse and can present as radiating pain to the elbow or even pain radiating down further into the wrist or hand. [drlox.com]
The most common symptom is mild to moderate aching pain in the proximal forearm, sometimes described as tiredness and heaviness. Use of the arm may cause a mild or dull aching pain to become deep or sharp. [clinicalgate.com]
The patient may also have pain at rest (especially at night), weakness in the thumb, and thenar atrophy. [mitchmedical.us]
For more information on Pain Management Topics and keywords Go to PainExam.com David Rosenblum, MD specializes in Pain Management and is the Director of Pain Management at Maimonides Medical Center and AABP Pain Managment For evaluation and treatment [painexam.libsyn.com]
- Swelling
Patients with significant soft-tissue swelling and symptoms or signs of median nerve dysfunction are especially at risk for worsening neuropathy after closed reduction and closely applied cast immobilization or after open reduction. [ncbi.nlm.nih.gov]
Applying ice, compression, and elevation to a soft tissue injury will help to reduce swelling, in turn reducing pressure on the median nerve. [sportsinjuryclinic.net]
Recovery Immediately following surgery, you will be encouraged to elevate your hand above your heart and move your fingers to reduce swelling and prevent stiffness. You should expect some pain, swelling, and stiffness after your procedure. [orthoinfo.aaos.org]
- Soft Tissue Swelling
Patients with significant soft-tissue swelling and symptoms or signs of median nerve dysfunction are especially at risk for worsening neuropathy after closed reduction and closely applied cast immobilization or after open reduction. [ncbi.nlm.nih.gov]
The possible causes of the compression include the tape over the volar forearm used to affix the arms to the padded arm board, an unexpected venous tourniquet effect in the face of third spacing, or generalized soft tissue swelling. [anesthesiology.pubs.asahq.org]
- Localized Edema
An existing anatomic abnormality, whether congenital or traumatic, can increase the predisposition to the development of AINS, especially if the area is challenged with concurrent localized edema. [emedicine.medscape.com]
Musculoskeletal
- Fracture
The mechanism of injury includes compression of the nerve by the displaced fracture, contusion of the nerve at the time of fracture or reduction, or the development of a compartment syndrome. [ncbi.nlm.nih.gov]
Herzberg G (2008) Perilunate and axial carpal dislocations and fracture-dislocations. J Hand Surg [Am] 33:1659–1668 CrossRef Google Scholar 2. [link.springer.com]
- Tinel's Sign
A Tinel’s sign is present in more than half of CTS cases; however, false-positive Tinel’s signs are common in the general population. [clinicalgate.com]
In the report by Wieman and Patel ( 28 ) on 33 limbs in 26 patients, 32 had a positive Tinel sign, yet 19 of 26 responded and 7 with positive Tinel signs did not. [care.diabetesjournals.org]
Signs include a positive Tinel's sign at the wrist (tingling in median nerve distribution on percussion over ventral wrist), positive Phalen's sign (similar findings within 45 seconds after placing patient's wrist in maximal flexion), pain or paresthesias [mitchmedical.us]
References:[3][2] Diagnostics Physical examination Bottle sign In the case of carpal tunnel syndrome, the following signs are also present: Tinel's sign Phalen's sign Diagnostic procedures References:[2][4] Treatment Avoid repetitive wrist activities [amboss.com]
- Muscle Weakness
[…] within the muscle itself.1) Significant weakness rare, mild weakness of FPL and APB most common6 Muscle bulk of pronator teres may be greater in symptomatic volar forearm Anterior interosseous syndrome Weakness may be detected in the FPL, pronator quadratus [now.aapmr.org]
Common symptoms include pain, numbness, and muscle weakness at the site of the nerve. Nerve compression syndromes are often caused by repetitive injuries. [healthline.com]
Multifocal motor neuropathy in a 45-year-old female patient with nonspecific muscle weakness of the right arm. [pubs.rsna.org]
For example, as the muscles in the legs aren't being used regularly, they can become very weak. As the muscles support the bones, muscle weakness can affect bone development. [nhs.uk]
Common signs and symptoms include numbness and tingling in feet or hands; burning pain in the arms and legs; sharp, jabbing, or electriclike pain; extreme sensitivity to touch; lack of coordination; muscle weakness or paralysis if motor nerves are affected [fortherecordmag.com]
- Thenar Muscle Atrophy
Thenar muscle atrophy (chronic injury) Recurrent branch of median nerve: Innervates muscles of the thenar eminence Damaged with lacerations of the radial-sided wrist and proximal palm Results in loss of thumb flexion, opposition, and abduction without [amboss.com]
muscle atrophy may occur. [fpnotebook.com]
Physical examination showed bilateral thenar muscle atrophy and muscle weakness of the abductor pollicis brevis, which was more prominent in the left hand. Tendon reflexes were normal and symmetric. [thenerve.net]
Atrophy 62. CLINICAL FEATURES SYMPTOMS Pain paresthesia tingling Awakens the pt. at night SIGNS Decreased grip strength Thenar muscle atrophy Tinels sign 63. [slideshare.net]
- Wrist Pain
The patients with ACTS initially had normal sensation and subsequently developed objective sensory loss (2-point discrimination greater than 15 mm) in the median nerve distribution associated with severe wrist pain. [ncbi.nlm.nih.gov]
Characterized by hand and wrist pain, CTS is a symptomatic distal median nerve neuropathy at the wrist and is the most commonly encountered entrapment neuropathy. [practicalpainmanagement.com]
If you have limited wrist motion or wrist pain, your doctor may order x-rays to exclude other causes for your symptoms, such as arthritis, ligament injury, or a fracture. Magnetic resonance imaging (MRI) scans. [orthoinfo.aaos.org]
Clinical Findings.— Patients with carpal tunnel syndrome experience a burning wrist pain, which may radiate either proximally to the shoulder and neck region or distally into the fingers. [pubs.rsna.org]
Psychiatrical
- Suggestibility
This pattern, preserved distal sensory action potential and abnormal peripheral SEPs were suggesting the presence of proximal sensory block conduction without wallerian degeneration. [ncbi.nlm.nih.gov]
It might be suggested that there was a possible median nerve axonal deterioration also. [hindawi.com]
Neurologic
- Peripheral Neuropathy
Routinely performed tests would have missed median neuropathy at wrist with concomitant peripheral neuropathy in 59 (37.3%) hands. [ncbi.nlm.nih.gov]
There was no correlation between peripheral neuropathy and gender (p=0.696). Conclusion: Despite the detailed neurological examination, subclinical peripheral neuropathy can be seen in patients with Behçet’s disease. [journal.turkderm.org.tr]
Alcohol consumption has a significant correlation with peripheral neuropathy (p=0.019). Conclusion: Exposure to vibration caused disorders in peripheral nerves system such as motor and sensory neuropathy, axonopathy, and CTS-induced vibration. [scholar.ui.ac.id]
December 17, 2012 Coding for Peripheral Neuropathy For The Record Vol. 24 No. 23 P. 25 Peripheral neuropathy involves damage to the peripheral nerves, which send information to and from the brain and spinal cord to other parts of the body. [fortherecordmag.com]
- Paresthesia
The physical examination must include two tests - flexion of the wrist to 90 degrees for 1 minute, which could result in paresthesia (known as the Phalen's sign) and percussion of the nerve at the carpal tunnel (the onset of paresthesia indicates a positive [symptoma.com]
[…] pain Neck pain Shaking or ringing the hands Pain/paresthesias associated with driving or holding a phone, book, or newspaper Perception of paresthesias involving all five digits Paresthesias radiating from neck and shoulder down the arm Sensory disturbance [clinicalgate.com]
A 33 year-old-man with paresthesia in first three fingers of the right hand after minor trauma of the arm was examined electrophysiologically. The proximal sensory median neuropathy was isolated which it is unusual in traumatic lesion. [ncbi.nlm.nih.gov]
[…] what is not affected in CTS what symptoms are first in CTS sensory paresthesias, later motor refers to a reduced sense of touch or sensation, or a partial loss of sensitivity to sensory stimuli. [quizlet.com]
Common symptoms include numbness and paresthesias in the sensory distribution of the median nerve (palmar surface of thumb, index finger, and middle finger; radial side of ring finger; radial two thirds of palm). [mitchmedical.us]
- Radiculopathy
We present two cases of proximal median neuropathy (PMN) associated with cervical radiculopathy which we diagnosed in our EMG laboratory over a short period of time. [ncbi.nlm.nih.gov]
Diagnostic Considerations CTS versus C6 or C7 radiculopathy Cervical radiculopathy usually causes neck and shoulder pain and restricted neck movements in acute radiculopathy. Cervical radiculopathy has absence of nocturnal pain and paresthesias. [emedicine.medscape.com]
Evaluation and treatment of suspected radiculopathy. Figure 3. Evaluation and treatment of suspected radiculopathy. Figure 4. Evaluation and treatment of suspected polyneuropathy (eg, multifocal mononeuropathy). Figure 4. [jaoa.org]
The peripheral lesions that enter into the differential diagnosis include median neuropathy in the region of the elbow, brachial plexopathy, and cervical radiculopathy. [clinicalgate.com]
- Cervical Radiculopathy
We present two cases of proximal median neuropathy (PMN) associated with cervical radiculopathy which we diagnosed in our EMG laboratory over a short period of time. [ncbi.nlm.nih.gov]
Diagnostic Considerations CTS versus C6 or C7 radiculopathy Cervical radiculopathy usually causes neck and shoulder pain and restricted neck movements in acute radiculopathy. Cervical radiculopathy has absence of nocturnal pain and paresthesias. [emedicine.medscape.com]
“Considering the extreme rarity of proximal median neuropathy, its association in both cases with cervical root disease supports the notion that the cervical radiculopathy may have predisposed the nerve to a second lesion along its course, resulting in [chiro-trust.org]
The peripheral lesions that enter into the differential diagnosis include median neuropathy in the region of the elbow, brachial plexopathy, and cervical radiculopathy. [clinicalgate.com]
- Clumsiness
Typically this causes pins-and-needles in the fingers, clumsiness, pain or numbness and later, weakness. Interestingly, different people report a wide range of symptoms and some may be in the forearm or even upper arm. [williamblake.com.au]
The patient may describe clumsiness or dropping objects. 3 Extremes of wrist flexion and extension in a constricted canal as the result of high force, high repetition, vibration or awkward posture (also observed with dystonia, athetosis or catatonia) [practicalpainmanagement.com]
[…] that grows in the wrist Infections Obesity If your body keeps extra fluids during pregnancy or menopause Rheumatoid arthritis Diseases that have abnormal deposits of protein in the body (amyloidosis) Symptoms Symptoms may include any of the following: Clumsiness [printer-friendly.adam.com]
[…] teres syndrome PTS can present with: - volar pain of the proximal lower arm - paresthesia of the volar forearm and the radial three digits and radial aspect of the fourth digit - weakness, on the other hand, is variable, often with unspecified grip clumsiness [neurologyneeds.com]
Compressive Insidious onset Pain is less severe and worsened by repetitive activity Slowly progressive weakness, loss of dexterity, clumsiness, and fatigue Surgical decompression may provide relief7,8 Inflammatory Acute onset Pain can be severe but short [now.aapmr.org]
Workup
The diagnosis of a median neuropathy can be made successfully if all steps during workup are conducted properly, including a detailed patient history, a careful physical examination, and laboratory or imaging studies in the diagnosis is unclear. Firstly, information regarding the onset and severity of symptoms, as well as their location and duration, is of essential importance to the physician. The physical examination must include two tests - flexion of the wrist to 90 degrees for 1 minute, which could result in paresthesia (known as the Phalen's sign) and percussion of the nerve at the carpal tunnel (the onset of paresthesia indicates a positive Tinel's sign) [2] [3]. If these measures do not provide enough clinical evidence, additional investigations include electromyography, nerve conduction studies, magnetic resonance imaging (MRI) and high-resolution ultrasonography (HRUS), a useful adjunctive method for the diagnosis of median neuropathy, being inexpensive, non-invasive and readily available [2] [5]. Because diabetes mellitus is an important risk factor for carpal tunnel syndrome, blood glucose levels should be evaluated in all patients who present with signs and symptoms suggestive of this condition [1] [2].
Treatment
Corrective osteotomy without carpal tunnel release is a sufficient treatment for neuropathy in malunited distal radius fractures. [ncbi.nlm.nih.gov]
As you consider any treatment, discuss them with your physician. [drlox.com]
See treatment for carpal tunnel syndrome References:[3][2] Median nerve neuropathy Summary Etiology Clinical features Anatomical principles Diagnostics Treatment [amboss.com]
Prognosis
Careful clinical evaluation and discerning evaluation of electrodiagnostic studies are helpful in determining the prognosis of recovery with nonoperative and operative management. [ncbi.nlm.nih.gov]
Outlook (Prognosis) Symptoms often improve without surgery. But more than one half of cases eventually need surgery. Even if surgery is successful, full healing can take months. [printer-friendly.adam.com]
These women may benefit from taking a higher daily dose of folic acid before they consider becoming pregnant. top What is the prognosis? Children with spina bifida can lead active lives. [ninds.nih.gov]
When this type of defect is detected, parents should seek out a multi-disciplinary team of specialists, including a pediatric neurosurgeon, to understand the condition and prognosis as well as to make an informed decision on the course of the pregnancy [aans.org]
In selected cases, nerve conduction studies at the onset of symptoms may provide insights into localization, mechanism, and prognosis. References Dhuner K: Nerve injuries following operations: A survey of cases occurring during a 6 year period. [anesthesiology.pubs.asahq.org]
Etiology
Contrary to earlier studies, this report demonstrates that GH-induced CTS is not an age-related phenomenon and alerts physicians to include GH abuse as a possible etiology of median neuropathy in athletes. [ncbi.nlm.nih.gov]
Etiology Traumatic: e.g., fractures (humerus fracture causing proximal lesion), carpal bone dislocations, or penetrating injuries (gunshots, lacerations, etc) Chronic compression; : e.g., in the carpal tunnel (see carpal tunnel syndrome; ) or between [amboss.com]
Etiological and pathological findings favored the conception of this disorder as some type of localized rheumatic disease. Immobilization of the wrist by a splint and administration of hydrocortisone relieved the symptoms in many cases. [jamanetwork.com]
Etiology This entrapment is more common in patients who are obese, wear tight underwear or pants, or who have diabetes. [casemed.case.edu]
Epidemiology
Level of Evidence : Level III, prognostic study Keywords Perilunate dislocations Perilunate fracture-dislocations Epidemiology Median neuropathy Carpal tunnel release This is a preview of subscription content, log in to check access. [link.springer.com]
Anterior interosseous nerve syndrome AINS is a rare entrapment syndrome, with comparatively little robust epidemiological data. AINS is said to account for less than 1% of neuropathies of the upper limb. [neurologyneeds.com]
PROXIMAL DIABETIC NEUROPATHY (PDN) OF THE LOWER LIMBS Clinical and epidemiological aspects – Diabetic patients, usually over the age of 50, may present proximal neuropathy of the lower limbs characterized by a variable degree of pain and sensory loss [scielo.br]
Epidemiologic and genetic aspects of spina bifida and other neural tube defects. Dev Disabil Res Rev. 2010;16(1):6-15. doi: 10.1002/ddrr.93. Review. Bassuk AG, Kibar Z. Genetic basis of neural tube defects. [ghr.nlm.nih.gov]
Pathophysiology
SIGNIFICANCE: Assessment of nerve conduction across the common entrapment sites could provide new insights into the pathophysiology of diabetic neuropathy related to metabolic factors. [ncbi.nlm.nih.gov]
In the vast majority of cases, however, the carpal tunnel is the site where the injury occurs, and the term "carpal tunnel syndrome" is used as a distinct clinical entity to describe the pathophysiological and clinical changes. [symptoma.com]
The pathophysiology of this type of lesion is mainly mechanical: a repeated and prolonged compression may develop either directly by the contracting muscle itself or by fixation against more rigid osteoligamentous tissues; the movements performed by our [jnnp.bmj.com]
The pathophysiology is not completely understood but can be considered compression of the median nerve traveling through the carpal tunnel. [ocneurosurgery.com]
It is believed that hyperglycemia alone can not explain all the pathophysiology of nerve injury and among the factors potentially involved the development stand to insulin resistance (IR) and abnormal lipid metabolism. [bdtd.ibict.br]
Prevention
All members of the Industrial Injuries and Prevention Committee of the American Society for Surgery of the Hand provided electrodiagnostic reports from their office practices indicating an electrodiagnosis of CTS or median neuropathy at the wrist. [ncbi.nlm.nih.gov]
Strict control of blood sugar levels is necessary to prevent further median nerve damage. [livestrong.com]
A focused neurophysiological approach is mandatory to reach the proper diagnosis and start specific treatment early enough to prevent possible irreversible hand function disabilities. [semanticscholar.org]
References
- Horinouchi S, Deguchi T, Arimura K, et al. Median neuropathy at the wrist as an early manifestation of diabetic neuropathy. J Diabetes Investig. 2014;5(6):709-713.
- Bland JDP. Carpal tunnel syndrome. BMJ. 2007;335(7615):343-346.
- Thatte MR, Mansukhani KA. Compressive neuropathy in the upper limb. Indian J Plast Surg. 2011;44(2):283-297.
- Melli G, Chaudhry V, Dorman T, Cornblath DR. Perioperative bilateral median neuropathy. Anesthesiology. 2002;97(6):1632-1634.
- Ginn SD, Cartwright MS, Chloros GD, et al. Ultrasound in the diagnosis of a median neuropathy in the forearm: case report. J Brachial Plex Peripher Nerve Inj. 2007;2:23.