The symptoms of ulnar nerve entrapment are manifested in the hand and forearm. The chief complaint of patients are numbness and paresthesia (prickling and tingling sensation) in the ring (fourth) and small (fifth) fingers, ulnar side of the hand (palm), and pain in the elbow. As the disorder advances, the mobility of the hand and affected fingers become impaired due to weakness of the muscles in the area. This results in difficulty with pinching motion between the thumb and index finger (as when picking objects) and grip with the hand. In the chronic stage, patients may present with an ulnar "claw hand" described as curling up of the small and ring fingers (metacarpophalangeal joint in extension and interphalangeal in flexion) secondary to a dysfunction or imbalance between extrinsic and intrinsic muscles of the hand.

Current provocative tests used to diagnose ulnar nerve entrapment include Tinel‘s test, elbow flexion, pressure (compression) per se, elbow flexion combined with pressure, and palpation of affected area for nerve tenderness and thickening. Yet, the specificity and sensitivity of these tests as diagnostic indicator for an entrapped ulnar nerve remains below the standards.

Classification of cubital tunnel syndrome according to severity of symptoms:

Grade I: Mild

• Infrequent paresthesia
• Decreased sensitivity to stimulation of palmar and dorsal surfaces of the small finger, and medial aspect of the ring finger
• Normal motor functions

Grade II: Moderate

• Persistent paresthesia
• Hypoesthesia of the palmar and dorsal surfaces of the small finger and medial aspect of the ring finger
• Mild muscle weakness innervated by the ulnar nerve
• Evidence suggestive of early muscular atrophy

Grade III: Severe symptoms

• Marked paresthesia
• Sensory loss of the palmar and dorsal surfaces of the small finger and medial aspect of the ring finger
• Functional and motor difficulties
• Atrophy of intrinsic muscles of the hand
• Claw hand ("Hand of Benediction")

Symptoms manifestation caused by entrapment and impingement of the ulnar nerve at the Guyon’s canal consist of:

• Atrophy of muscles, mainly the hypothenar and interossei with sparing of the thenar muscles
• Weak finger abduction and adduction movement (interossei)
• Weak thumb adduction movement (adductor pollicis)
• Sensory loss and pain involving the palmar surface of the small finger and medial aspect of the ring finger

• Inflammation

  Treatment Local steroid injection reduces inflammation and pain Nonoperative treatment Early conservative treatment is key for reducing the symptoms of ulnar nerve entrapment. [pathologies.lexmedicus.com.au]

  Medication to treat inflammation and pain may also be necessary. [neuroendomke.com]

  Tendonitis and inflammation in these flexors can press on the nerve, which might be caused by overuse, misalignment in technique, or repetitive trauma. [musicianshealthcollective.com]

  For those who continue to have problems despite these treatments, consideration may be given to an injection in the area of nerve compression/inflammation. If symptoms are persistent or severe, surgery may be considered. [sportsmedicine.mayoclinic.org]

• Disability

  It is the cause of considerable pain and disability for patients. When appropriately diagnosed, this condition may be treated by both conservative and operative means. [doi.org]

  The extent of the deformity and disability depends on the site of the lesion. [patient.info]

  […] neurodynamic test (ULTT3) may increase the patient’s symptoms Diagnostic Tests for Ulnar Nerve Entrapment Imaging for OA, bone spurs, or bone cysts Nerve Conduction Studies (EMG) If fracture/dislocation is suspected, plain film x-ray Outcome Measures[12] Disabilities [physio-pedia.com]

  Such treatment in MMN may worsen symptoms, potentially leading to progressive motor symptoms, including muscle weakness, atrophy, and significant motor disability. [touchneurology.com]

• Hand Pain

  Abstract Ulnar nerve entrapment at the elbow is a common cause of arm and hand pain, paresthesias, and weakness. Its characteristics and the appropriate diagnostic tests should be known to all primary care physicians. [ncbi.nlm.nih.gov]

  Numbness or tingling in the hand is the most common symptom Especially the small and ring fingers Many patients notice the symptoms at night, when resting their elbow on a hard surface, and with heavy use Some patients notice weakness in their hand Pain [newwestsportsmedicine.com]

  Common symptoms of ulnar nerve entrapment are: Numbness in the hand, ring finger (third finger from your thumb) and little finger Hand pain Hand and thumb clumsiness caused by muscle weakness The symptoms of ulnar nerve entrapment may be similar to symptoms [stmarysmaine.com]

  Common symptoms are: Numbness in your hand, ring finger (third finger from your thumb) and little finger Hand pain Hand and thumb clumsiness caused by muscle weakness The symptoms of cubital tunnel syndrome may be similar to symptoms of other medical [ohsu.edu]

  Abstract Ulnar nerve entrapment can be a cause of elbow, wrist, and hand pain. The ulnar nerve travels through several canals or tunnels, and, like the better-known carpal tunnel syndrome, these tunnels can cause entrapment. [link.springer.com]

• Forearm Pain

  Some patients also have forearm pain. [aafp.org]

  Common signs and symptoms of the condition include: Feeling of weakness or tenderness of the hand A tingling sensation on the palms and fingers Increased sensitivity to cold within the hand or forearm Pain within the elbow joint How is Ulnar Nerve Entrapment [dovemed.com]

  Symptoms indicative of recurrent ulnar nerve entrapment include pain, tingling, numbness, or cold intolerance in the ring and little finger, which may be associated with pain and a positive Tinel sign at the elbow and weakness in the forearm or hand [ncbi.nlm.nih.gov]

• Arm Pain

  Other common tennis elbow symptoms can include arm stiffness and difficulty in extending and straightening your arm(especially in the morning), arm pain performing simple tasks such as shaking someones hand, turning a doorknob or difficulty in even holding [tenniselbowtips.com]

  Nerves, like the ulnar nerve, also carry signals back to the brain about sensation in the arm, forearm and hand. Therefore neuropathy may also present as numbness, pain and tingling sensations. [healthhype.com]

• Heart Block

  Heart block, enlargement of the heart wall, enlargement of heart, slight oxygen deprivity - ASA. Levothyroxine - lazy thyroid. Gabapentin - neuropathy. Clonazepam, lithium, quetiapine, quetiapine XR, escitalopram - depression. [community.diabetes.org]

• Arthritis

  Imaging studies: X-rays can help identify things such as arthritis or a fracture. Ultrasound can reveal if there is impaired movement of the ulnar nerve. [tariqjaved.com]

  This article originally appeared in Cleveland Clinic Arthritis Advisor. [health.clevelandclinic.org]

  If diabetes, injury and arthritis are present they are given medical priority. [pathologies.lexmedicus.com.au]

  The cause of most cases is unknown, although the condition may accompany a history of elbow fracture, dislocation, arthritis or repeated minor trauma. [uclahealth.org]

• Muscle Weakness

  If conservative treatment fails to provide relief, or if there is muscle weakness, surgery to relieve pressure on the nerve may be recommended. Get Relief for Your Orthopaedic Pain Today! [ksfortho.com]

  Pain and sensory changes respond better than muscle weakness and atrophy. [uclahealth.org]

  Symptoms also include a weak grip, difficulty controlling movement, and pain or tenderness. If left untreated this condition could escalate to muscle weakness and permanent injury to the arm or hand. [hss.edu]

  If conservative methods do not improve your symptoms, or if the nerve compression is causing muscle weakness or damage in your hand, your doctor may recommend surgery. Nerve gliding exercises. [youtube.com]

  Decreased grip and pinch strength and muscle weakness. Tenderness along the inside of the elbow. The majority of the diagnosis is in the history. Symptoms are often quite typical. [orthosports.com.au]

• Elbow Pain

  The patient contacted our department with chronic, diffuse bilateral elbow pain irradiating into both forearms. She experienced typical nocturnal paresthesias involving digit IV and V of both hands. [ncbi.nlm.nih.gov]

  Duration of symptoms was only 2 months, the patient was 28 years old, and medial elbow pain was very pronounced. Neurophysiologic tests are used for the diagnosis and confirmation of ulnar neuropathy at the elbow. [doi.org]

  Symptoms This entrapment causes pain, numbness and/or tingling in the little finger and half of the ring finger, elbow pain and hand weakness. Early symptoms may be purely weakness. Often the symptoms are made worse by cold temperature. [uclahealth.org]

  Topic Resources Cubital tunnel syndrome is compression or traction of the ulnar nerve at the elbow. Symptoms include elbow pain and paresthesias in the ulnar nerve distribution. [msdmanuals.com]

• Osteophyte

  - Medial Epicondyle: nerve may be irritated by medial epicondyle osteophytes; - Cubital tunnel (FCU Aponeurosis) - roof of cubital tunnel is formed by aponeurosic attachment of 2 heads of FCU, which spans in arcade like manner from medial epicondyle [wheelessonline.com]

  Etiology Specific causes of nerve compression at the cubital tunnel include: overuse subluxation/dislocation of the ulnar nerve from congenital laxity in fibrous tissue extrinsic compression humeral fracture with loose bodies or callus formation osteophytic [radiopaedia.org]

  […] and denervation has not yet occurred poor prognosis correlates most with intrinsic muscle atrophy ulnar nerve decompression and anterior transposition indications failed in situ release throwing athlete patient with poor ulnar nerve bed from tumor, osteophyte [orthobullets.com]

  The nerve can become entrapped in the cubital tunnel of the elbow during heavy manual work or following a previous poorly healed supracondylar fracture of the humerus or due to osteophytic encroachment in osteoarthritis. [patient.info]

• Muscular Atrophy

  If no muscle weakness and no muscular atrophy exist, conservative measures with immobilization of the elbow, padding and splinting of the elbow and analgesic-anti-inflammatory drugs can be tried. [uniklinikum-saarland.de]

  Significant functional and motor impairment Muscle atrophy of the hand intrinsics Possible digital clawing of fourth and fifth digits (Sign of Benediction) Guyon's Canal Syndrome symptoms include: Muscular atrophy - Primarily the hypothenar muscles and [physio-pedia.com]

  Alternatively, subcutaneous transposition is frequently used in the case of athletes (gymnasts) whose activity involves throwing and who do not present muscular atrophy. [symptoma.com]

  Advanced neuropathy is indicated by muscular hypotrophy or atrophy of the intrinsic muscles innervated by the ulnar nerve. Typically, atrophy initially involves the first dorsal interosseous muscle and then extends to the hypothenar muscles. [parjournal.net]

  muscular atrophy by the clustering index method. [researchmap.jp]

• Tingling

  The tingling and numbness in the hands accompanied by burning is a nerve symptom and specifically a nerve symptom from the ulnar nerve, a nerve which innervates some of the muscles of the hand as well as the forearm. [southplattesentinel.com]

  Compression of the ulnar nerve at the elbow manifests itself by tingling at the hand’s two last fingers as well as weakness in the hand. [arthroscopie-membre-superieur.eu]

  It can become trapped on the inside of the elbow, which is what causes that tingling sensation. [pthealth.ca]

  Similar to the phenomenon of a person’s arm “going to sleep,” or “hitting your funny bone,” a pinched ulnar nerve can result in tingling, pain and numbness. [hopkinsmedicine.org]

  Usually the tingling you get when bumping the nerve last a few seconds only but the ulnar nerve also can be the cause of more serious and permanent problems in the fingers and hand. [orthosports.com.au]

• Cervical Radiculopathy

  METHODS: We calculated the ratio between FDI-CV and ADM-CV (IN-RATIO) in 60 consecutive UNE patients, 40 norms, and 16 patients with lower cervical radiculopathy. [ncbi.nlm.nih.gov]

  Cubital tunnel syndrome may be confused with proximal nerve compression such as that caused by thoracic outlet syndrome (TOS) or C8-T1 cervical radiculopathy (see table Motor and Reflex Effects of Spinal Cord Dysfunction by Segmental Level). [msdmanuals.com]

• Numbness of the Hand

  The tingling and numbness in the hands accompanied by burning is a nerve symptom and specifically a nerve symptom from the ulnar nerve, a nerve which innervates some of the muscles of the hand as well as the forearm. [southplattesentinel.com]

  You may experience: Tingling and numbness in little and ring fingers (especially at night). Numbness in your hand when the elbow is bent (holding the phone to your ear). Difficulty using your hand for day to day activities. [orthosports.com.au]

  Symptoms of this problem include: Tingling of the little and ring fingers Numbness of the hand when the elbow is bent Reduced hand coordination Reduced hand strength Tenderness at the inside of the elbow Pain along the inside of the shoulder blade Your [poadocs.com]

  Symptoms of ulnar nerve entrapment include: Numbness in the ring and little fingers, particularly at night Numbness in the hand, particularly when the elbow is bent Muscle weakness Decreased coordination Tenderness on the inside of the elbow Diagnosis [neuroendomke.com]

• Paresis

  Thus, the decrease of sensation disturbance and loss of strength (paresis) can take a long time. In case cubital tunnel syndrome has caused atrophy, the improvement is often incomplete. [betaklinik.de]

  However, concomitant alcoholism, diabetes mellitus, and isoniazid treatment make their course poorer. [2] A case of tuberculous radiculitis in the lumbosacral region resulting in flaccid paresis of the lower limbs has been reported by Myllylδ et al ., [annalsofian.org]

• Hand Paralysis

  Ulnar nerve entrapment with deficit : hand sensibility is diminished and muscle wasting affects some muscles of the thumb, hand paralysis and deformity can occur: this is called the ulnar claw. [arthroscopie-membre-superieur.eu]

Clinical assessments often suffice to establish the diagnosis of ulnar nerve entrapment. However, conduction studies are recommended when clinical findings are unclear and when surgery is being considered as part of the treatment strategy.

Electrodiagnostic studies consisted of nerve conduction study and often times needle electromyography (EMG), are useful in validating the diagnosis of ulnar nerve entrapment and establishing baseline results and in ruling out other possible causes of peripheral nervous system disorder [19].

MRI and ultrasonography are also useful confirmatory tests for ulnar nerve entrapment [20] [21] [22] [23] [24]. For instance, ultrasonography serves to detect altered ultrasound waves and thickened ulnar nerve, a commonly observed presentation of ulnar nerve entrapment. On the other hand, MRI shows enlarged nerve and increased signal intensity on T2-weighted or short T1 inversion recovery (STIR) sequences [21]. The results of MRI may vary with the specific cause.

Treatment of ulnar nerve entrapment involves night splinting, with elbow extended at 45 degrees, and use of elbow pad at daytime. Surgery is recommended if symptoms fail to improve or resolve with conservative treatment.

Indications for surgical decompression of ulnar nerve entrapment:

• Symptoms do not improve after 6-12 weeks.
• Development of palsy or paralysis
• Evidence of persistent lesion such as muscle wasting or curling of ring and small fingers (claw hand)

The method of choice for ulnar nerve entrapment at the elbow is decompression with anterior transposition. The ulnar nerve is transferred to a suitable site away from the original lesion while being stretched a few centimeters to decrease the tension imposed upon it when the elbow is flexed [25]. The primary advantage is that transfers the ulnar nerve from an unsuitable bed to one that is less scarred. However, this method is more technically complicated than simple ulnar compression and with it comes the risk of devascularization of the nerve.

Alternatively, subcutaneous transposition is frequently used in the case of athletes (gymnasts) whose activity involves throwing and who do not present muscular atrophy. The procedure is simple and appropriate for resolving subluxation and traction on the nerve [26]. However, the nerve may be hypersensitive on account of its new superficial location and the blood supply to the nerve may be disrupted with the transposition.

Submuscular transposition has been shown to have the least recurrences with severe ulnar nerve compression [27]. It allows transferring of the nerve to an unscarred bed. The procedure is appropriate for patients who are emaciated, preventing hypersensitivity of the nerve in case of subcutaneous transposition. Anterior submuscular transposition is considered the method of choice for athletes who throw. It is, however, technically demanding where extensive dissection is involved and postoperative outcome is poor, with 5-10 percent risk of elbow flexion contracture. Surgical dissection may result in extensive scarring which will make revision difficult in case of recurrence.

Successful surgical intervention has been achieved in 85 to 95 percent of cases, although the benefit is more for sensory rather than for motor functions. Prognosis is influenced by the following observations:

• Motor amplitude of 10 percent of normal indicates low probability of full recovery.
• Nerve regeneration with pain and paresthesia may occur, which are believed due to random generation of impulses of diseased nerves.
• An enlarged ulnar nerve (diameter more than 3.5 mm) at the elbow observed on the initial sonogram is linked to persistent symptoms or signs, with or without treatment [14].
• The result of treatment does not correlate with the baseline clinical features or duration of symptoms prior to treatment.
• Motor conduction velocity diminished or blocked across the elbow signifies good prognosis [15].

Poor surgical prognosis is associated with: age (if more than 50 years); coexisting diabetes or other peripheral polyneuropathy; muscle wasting and denervated ulnar nerve supplied muscles; unresponsive sensory function of the ulnar nerve; and postoperative positioning of the ulnar nerve in connection to the medial epicondyle [16] [17] [18].

The ulnar nerve is vulnerable at the elbow and, rarely, the wrist. A major cause of cubital tunnel syndrome is the habit of leaning on the elbow. Another cause is repeated, excessive flexion of the elbow as seen in baseball pitchers (particularly sliders), which is detrimental to the medial elbow ligaments. Cubital tunnel syndrome is less prevalent than carpal tunnel syndrome.

Conditions that may contribute to ulnar nerve entrapment at or near the elbow are as follows:

• Metabolic dysfunctions as in diabetes
• Temporary surgical closure of the brachial artery [7]
• Subdermal insertion of contraceptive implant [8]
• Transient immobilization under anesthesia
• Venipuncture [9]
• Hemophilia [10] 
• Blunt trauma
• Deformities of limbs and joints as in rheumatoid arthritis
• Nutritional deficiency resulting in muscle atrophy and loss of adipose tissue
• Cigarette smoking [11]

Conditions that may contribute to ulnar nerve entrapment at in the wrist area or Guyon's canal are as follows:

• Blunt injuries
• Fractures
• Presence of ganglionic cysts or tumors
• Aberrant artery
• Idiopathic (hitherto unknown causes)

Cubital tunnel syndrome is primarily seen in individuals who tend to lean on their elbows habitually or who are subjected to repeated flexion of the elbows in the performance of their tasks. The repetitive stress can lead to entrapment and/or compression of the ulnar nerve in the cubital tunnel, the passage formed by the convergence of the medial epicondyle with the flexor carpi ulnaris and ligaments of the olecranon process of the ulna.

Guyon’s canal syndrome is caused by excessive pressure on the wrist and hand such as in weight lifting, holding on to a handlebar in cycling or construction equipment, hence the term, "handle bar palsy". The ulnar nerve becomes sequestered in the canal of Guyon situated between the hook of the hamate and the transverse carpal ligament. Activities that predispose to this syndrome are frequent or too much gripping, twisting, repetitive wrist and hand motions, keeping the hand flexed and the ulna deviated for long periods of time as in gymnastics or manual labor.

Ulnar nerve entrapment at the elbow is alternatively referred to as UNE. UNE is considered the second most common among the various types of focal neuropathy. The most common focal neuropathy is found at the carpal tunnel, also known as the median neuropathy at the wrist.

A study in Italy estimated the annual overall incidence of UNE was 24.7 cases per 100,000 person years, nearly twice as much in men, 32.7 per 100,000 compared to 17.2 per 100,000 in women [12]. From an extensive database obtained from general practice in the United Kingdom, the annual incidence of ulnar neuropathy involving all anatomic locations was 25.2 per 100,000 for men and 18.9 per 100,000 in women [13].

The cubital tunnel syndrome and Guyon's canal syndrome or ulnar tunnel syndrome affect the elbow and the wrist, respectively. Of these two sites, the elbow is more prone to the disorder than the latter. The ulnar nerve may be sequestered when the large bones of the upper extremity (radius, ulna, or humerus) sustain a fracture. Pathology of blood vessels, though rarely, can also cause compression of the ulnar nerve.

Factors responsible for ulnar nerve neuropathy include:

• Excessive and prolonged use of the wrist and elbow
• Dislocation/subluxation of the ulnar nerve from inborn defect in fibrous tissue
• Callus formation from fracture of the humerus
• Osseous outgrowth from the epicondyle or olecranon
• Impingement from an accessory muscle (anconeus epitrochlearis), soft tissue (tumor), ganglionic cyst, hematoma or osteochondroma
• Inflammation of synovial membrane (as in rheumatoid arthritis)
• Infection (e.g. tuberculosis)
• Thickened cubital tunnel ligament

In summary, cubital tunnel syndrome is impingement of the ulnar nerve, caused by prolonged compression of the elbow against a hard surface, fracture of the bones of the forearm and upper arm, excessive flexion of the elbow, bone, and vascular pathologies at the elbow area. Guyon’s canal syndrome is impingement of the ulnar nerve, caused by excessive pressure on the wrist as when holding on to the handle bar in cycling or weight-lifting, or the jackhammer by the construction worker, fracture of the forearm and upper arm bones, and vascular and bone pathologies. Trauma, abnormalities, or pathological conditions in other sites may also contribute to ulnar nerve neuropathy.

The best way to prevent ulnar nerve entrapment from becoming a serious health problem is to seek medical attention as soon as any symptom of pain, tingling, numbness, or difficulty of movement referable to the elbow and wrist, the ring (fourth) and small (fifth) fingers in particular, are suspected. These may be experienced by athletes or gymnasts, construction workers, or any person habitually and excessively using the hand or forearm in performing certain tasks. Consultation with an occupational therapist can help identify the cause of ulnar nerve entrapment.

Ulnar nerve entrapment is the second most frequent abnormality of the peripheral nervous system in the upper limb, after that of the median nerve [1] [2].

Entrapment of the ulnar nerve most likely occurs at the site of elbow region, specifically the cubital tunnel [3], or in the epicondylar (ulnar) groove. The second most probable site of entrapment is at or adjacent to the wrist, particularly at the Guyon's canal [1] [4] [5] [6]. Nerve entrapment is also likely to occur in the forearm, either below the wrist and within the hand, or just above the below.

Ulnar nerve entrapment is caused by habitual or occupational activities that impose excessive stress on the upper extremities such as in sports or manual labor. Predisposing factors are multifarious - traumatic, metabolic, nutritional, idiopathic, deformities, tumors, or iatrogenic. Diagnosis is based on clinical assessment, MRI, ultrasonography and some new techniques such as electromyography. Treatment is conservative or surgical. Prevention is through avoidance of overuse or inappropriate use of the upper extremities.

Ulnar nerve entrapment is a functional disorder whereby the nerve is pinched or compressed by adjoining tissues as it passes through the wrist or elbow, causing pain, and later, more pronounced symptoms. It is the second most common cause of ulnar neuropathy (after the median nerve entrapment).

Two main sites involved are the cubital tunnel or the epicondylar groove at the elbow and Guyon's canal at the wrist. However, impingement may also occur in the forearm between the wrist and the elbow, in the hand, or proximal part of the upper arm.

Impingement or injury of the ulnar nerve may manifest as loss of sensory function and paralysis of the muscles supplied by the nerve. Patients may complain of paresthesia along the ring (fourth) and small (fifth) fingers, with difficulty of hand grip. In advanced stages, there is loss of intrinsic motor function and wasting in the hand, or claw hand (curling of the ring and small fingers). As the ulnar nerve bifurcates at the wrist, only the opponens pollicis, superficial head of the flexor pollicis brevis, and lateral 2 lumbricals are functioning.

Initially, conservative (nonsurgical) treatment is prescribed. Otherwise, if symptoms persist and in the event of continuing weakness or loss of motor function, surgical intervention should be considered. Several surgical strategies are available, with proven satisfactory outcomes.

1. Aguiar PH, Bor-Seng-Shu E, Gomes-Pinto F, Almeida- Leme RJ, Freitas AB, Martins RS, et al. Surgical management of Guyon’ s canal syndrome, an ulnar nerve entrapment at the wrist: report of two cases. Arq Neuropsiquiatr. 2001 Mar;59(1):106-11.
2. Spinner M, Spencer PS. Nerve compression lesions of the upper extremity. A clinical and experimental review. Clin Orthop Relat Res. 1974 Oct; 46-67. 
3. Campbell WW, Pridgeon RM, Riaz G, Astruc J, Sahni KS. Variations in anatomy of the ulnar nerve at the cubital tunnel: pitfalls in the diagnosis of ulnar neuropathy at the elbow. Muscle Nerve. 1991 Aug;14(8):733-8.
4. Szabo RM, Steinberg DR. Nerve Entrapment Syndromes in the Wrist. J Am Acad Orthop Surg. 1994 Mar;2(2):115-123.
5. Elhassan B, Steinmann SP. Entrapment neuropathy of the ulnar nerve. J Am Acad Orthop Surg. 2007 Nov; 15(11):672-81.
6. Pearce C, Feinberg J, Wolfe SW. Ulnar neuropathy at the wrist. HSS J. 2009 Sep;5(2):180-3; quiz 184-5.
7. Swenson JD, Hutchinson DT, Bromberg M, Pace NL. Rapid onset of ulnar nerve dysfunction during transient occlusion of the brachial artery. Anesth Analg. 1998 Sep; 87(3):677-80.
8. Marin R, McMillian D. Ulnar neuropathy associated with subdermal contraceptive implant. South Med J. 1998 Sep; 91(9):875-8.
9. Masoorli S, Angeles T, Barbone M. Danger points. How to prevent nerve injuries from venipuncture. Nursing. 1998 Sep; 28(9):34-9; quiz 40.
10. Chang C, Shen M. Mononeuropathy multiplex in hemophilia: an electrophysiologic assessment. Eur Neurol. 1998 Jul; 40(1):15-8.
11. Richardson JK, Jamieson SC. Cigarette smoking and ulnar mononeuropathy at the elbow. Am J Phys Med Rehabil. 2004 Sep; 83(9):730-4.
12. Mondelli M, Giannini F, Ballerini M, et al. Incidence of ulnar neuropathy at the elbow in the province of Siena (Italy). J Neurol Sci. 2005; 234:5.
13. Latinovic R, Gulliford MC, Hughes RA. Incidence of common compressive neuropathies in primary care. J Neurol Neurosurg Psychiatry. 2006; 77:263.
14. Osborne GV. The surgical treatment of tardy ulnar neuritis. J Bone Joint Surg Am. 1957; 39B:782.
15. Beekman R, Wokke JH, Schoemaker MC, Lee ML, Visser LH. Ulnar neuropathy at the elbow: follow-up and prognostic factors determining outcome. Neurology. 2004 Nov 9; 63(9):1675-80.
16. Mandelli C, Baiguini M. Ulnar nerve entrapment neuropathy at the elbow: decisional algorithm and surgical considerations. Neurocirugia (Astur). 2009 Feb; 20(1):31-8.
17. Terzis JK, Kokkalis ZT. Outcomes of secondary reconstruction of ulnar nerve lesions: our experience. Plast Reconstr Surg. 2008 Oct; 122(4):1100-10.
18. Terzis JK, Kostopoulos VK. Vascularized ulnar nerve graft: 151 reconstructions for posttraumatic brachial plexus palsy. Plast Reconstr Surg. 2009 Apr; 123(4):1276-91.
19. American Association of Electrodiagnostic Medicine, Campbell WW. Guidelines in electrodiagnostic medicine. Practice parameter for electrodiagnostic studies in ulnar neuropathy at the elbow. Muscle Nerve Suppl. 1999; 8:S171.
20. Filler AG, Maravilla KR, Tsuruda JS. MR Neurography and muscle MR imaging for image diagnosis of disorders affecting the peripheral nerves and musculature. Neurol Clin. 2004; 22:643.
21. Andreisek G, Crook DW, Burg D, et al. Peripheral neuropathies of the median, radial, and ulnar nerves: MR imaging features. Radiographics. 2006; 26:1267.
22. Koenig RW, Pedro MT, Heinen CP, et al. High-resolution ultrasonography in evaluating peripheral nerve entrapment and trauma. Neurosurg Focus. 2009; 26:E13.
23. Bäumer P, Dombert T, Staub F, et al. Ulnar neuropathy at the elbow: MR neurography--nerve T2 signal increase and caliber. Radiology. 2011; 260:199.
24. Beekman R, Visser LH, Verhagen WI. Ultrasonography in ulnar neuropathy at the elbow: a critical review. Muscle Nerve. 2011; 43:627.
25. Kleinman WB. Cubital tunnel syndrome: anterior transposition as a logical approach to complete nerve decompression. J Hand Surg Am. 1999 Sep; 24(5):886-97.
26. Macnicol MF. The results of operation for ulnar neuritis. J Bone Joint Surg Br. 1979 May; 61-B (2):159-64.
27. Janes PC, Mann RJ, Farnworth TK. Submuscular transposition of the ulnar nerve. Clin Orthop Relat Res. 1989 Jan; 225-32.