New near-nerve needle nerve conduction technique: differentiating epicondylar from cubital tunnel ulnar neuropathy.

At the elbow, the ulnar nerve is compressed most commonly either in the epicondylar groove or at the cubital tunnel. While conventional electrodiagnosis may localize an ulnar neuropathy to the elbow, separating epicondylar syndrome (tardy ulnar nerve palsy) from cubital tunnel syndrome is more difficult. We describe a new method using a near-nerve needle technique for distinguishing these two types of ulnar neuropathy at the elbow. We placed three active needle electrodes across the elbow: the first was 4 cm above, and the second and third were 1.5 cm and 6 cm below the medial epicondyle, respectively. The latter two points were chosen because of the presence of the cubital tunnel in this segment. Sensory, motor, and mixed nerve conduction studies (NCS) were performed on these two segments (elbow segment and cubital tunnel segment) in 26 normal nerves and normal data were established. We also present 7 cases of epicondylar ulnar nerve palsy and 1 case of cubital tunnel syndrome in which we were able to confirm the diagnosis with the present method. In 3 cases of epicondylar ulnar nerve palsy, the present method accurately localized the lesion when other methods failed. We believe that this method will be helpful in distinguishing cubital tunnel syndrome from epicondylar ulnar nerve palsy, especially in early ulnar neuropathy in which only sensory fibers are involved.     

Simple decompression of the ulnar nerve at the elbow via proximal and distal mini skin incisions

The purpose of the present study was to describe a new minimally invasive surgical technique for decompression of the ulnar nerve at the elbow for treatment of cubital tunnel syndrome. Four patients underwent surgical treatment for cubital tunnel syndrome. Preoperative clinical states were classified by using the McGowan grading system and the postoperative states were recorded by using the Wilson and Krout grading system. Preoperative and last follow-up electromyographic results were also recorded. At the last follow-up, three patients were recorded as excellent and one patient was recorded as good according to Wilson and Krout grading system. One patient showed improvement in sensory nerve conduction velocity another showed improvement in motor nerve conduction velocity at the last follow-up. We conclude that simple decompression of the ulnar nerve at elbow via proximal and distal mini skin incisions is an effective, technically simple and safe surgical method in the treatment of cubital tunnel syndrome.     

The cubital tunnel syndrome: diagnosis and precise localization

The cubital tunnel syndrome is a subgroup of ulnar neuropathies arising at the elbow, with nerve entrapment under the aponeurosis connecting the two heads of the flexor carpi ulnaris muscle. To separate this condition more clearly from tardy ulnar palsy, the clinical and electrophysiological features of 9 patients are presented, 6 of whom had the syndrome bilaterally. There was no history of trauma and no clinical or roentgenographic evidence of joint deformity in any of the patients. In 9 of the 15 ulnar nerves, abnormal conduction was localized to the level of the cubital tunnel (1.5 to 3.5 cm distal to the medial epicondyle). The findings were confirmed intraoperatively in 7 patients and corresponded to a tight band compressing the ulnar nerve and causing narrowing at the cubital tunnel with swelling proximally. This syndrome represents a common and distinct subgroup of ulnar neuropathies at the elbow.     

Ultrasound Diagnosis of Double Crush Syndrome of the Ulnar Nerve by the Anconeus Epitrochlearis and a Ganglion

Double compression of the ulnar nerve, including Guyon''s canal syndrome associated with cubital tunnel syndrome caused by the anconeus epitrochlearis muscle, is a very rare condition. We present a case of double crush syndrome of the ulnar nerve at the wrist and elbow in a 55-year-old man, as well as a brief review of the literature. Although electrodiagnostic findings were consistent with an ulnar nerve lesion only at the elbow, ultrasonography revealed a ganglion compressing the ulnar nerve at the hypothenar area and the anconeus epitrochlearis muscle lying in the cubital tunnel. Careful physical examination and ultrasound assessment of the elbow and wrist confirmed the clinical diagnosis prior to surgery.     

Applied anatomical study of the vascularized ulnar nerve and its blood supply for cubital tunnel syndrome at the elbow region

Cubital tunnel syndrome is often accompanied by paresthesia in ulnar nerve sites and hand muscle atrophy. When muscle weakness occurs, or after failure of more conservative treatments, anterior transposition is used. In the present study, the ulnar nerve and its blood vessels were examined in the elbows of 18 adult cadavers, and the external diameter of the nutrient vessels of the ulnar nerve at the point of origin, the distances between the origin of the vessels and the medial epicondyle of the humerus, and the length of the vessels accompanying the ulnar nerve in the superior ulnar collateral artery, the inferior ulnar collateral artery, and the posterior ulnar recurrent artery were measured. Anterior transposition of the vascularized ulnar nerve was performed to treat cubital tunnel syndrome. The most appropriate distance that the vascularized ulnar nerve can be moved to the subcutaneous tissue under tension-free conditions was 1.8 ± 0.6 cm(1.1–2.5 cm), which can be used as a reference value during the treatment of cubital tunnel syndrome with anterior transposition of the vascularized ulnar nerve.     

Symptomatic epineural ganglion cyst of the ulnar nerve in the cubital tunnel: a case report and brief review of the literature

An unusual case of pain and weakness in the hand and forearm due to a ganglion cyst of the ulnar nerve at the elbow is presented. The patient was managed initially as a case of cervical disc disease and cervical spondylosis and later as a case of carpal tunnel syndrome at an another institution. Cervical radiography and cervical magnetic resonance imaging scans were inconclusive. Neurosurgical referral revealed tenderness at the right cubital tunnel, weakness of the right hand and forearm muscles, and sensory deficit along the medial border of the forearm and the hand. The diagnosis of ulnar nerve compression at the elbow was made. Nerve conduction studies of the ulnar nerve at the elbow confirmed the diagnosis. A ganglion cyst of the ulnar nerve was excised microsurgically with a complete postoperative sensory motor recovery.     

Riche-Cannieu anastomosis and a paradoxical preservation of thenar muscles in carpal tunnel syndrome: a case report]

A 72-year old woman had been suffered from a dysesthesia in the left median nerve distribution, followed by a dysesthesia in the right ulnar distribution. Neurological examination revealed weakness in the right intrinsic hand muscles with the ipsilateral thenar and hyothenar atrophy. Paradoxical preservation of the left thenar muscles was a clinical challenge. Nerve conduction studies disclosed bilateral carpal tunnel syndrome and the right cubital tunnel syndrome. In needle electromyography, however, the left abductor pollicis brevis and opponens pollicis muscles had normal motor unit potentials without denervation activity. The needle recording of the left abductor pollicis brevis muscle showed a good motor response with a negative deflection by the left ulnar nerve stimulation, indicating an ulnar to median nerve innervation, i.e., Riche-Cannieu anastomosis. A Riche-Cannieu anastomosis in a setting of a median or ulnar nerve injury can produce confusing clinical and electrodiagnostic findings. We reviewed clinical findings, electrophysiological data, and the impact of a Riche-Cannieu anastomosis in median nerve injury.     

Anterior subcutaneous transposition of the ulnar nerve improves neurological function in patients with cubital tunnel syndrome

Although several surgical procedures exist for treating cubital tunnel syndrome, the best surgical option remains controversial. To evaluate the efficacy of anterior subcutaneous transposition of the ulnar nerve in patients with moderate to severe cubital tunnel syndrome and to analyze prognostic factors, we retrospectively reviewed 62 patients(65 elbows) diagnosed with cubital tunnel syndrome who underwent anterior subcutaneous transposition. Preoperatively, the initial severity of the disease was evaluated using the Mc Gowan scale as modified by Goldberg: 18 patients(28%) had grade IIA neuropathy, 20(31%) had grade IIB, and 27(42%) had grade III. Postoperatively, according to the Wilson Krout criteria, treatment outcomes were excellent in 38 patients(58%), good in 16(25%), fair in 7(11%), and poor in 4(6%), with an excellent and good rate of 83%. A negative correlation was found between the preoperative Mc Gowan grade and the postoperative Wilson Krout score. The patients having fair and poor treatment outcomes had more advanced age, lower nerve conduction velocity, and lower action potential amplitude compared with those having excellent and good treatment outcomes. These results suggest that anterior subcutaneous transposition of the ulnar nerve is effective and safe for the treatment of moderate to severe cubital tunnel syndrome, and initial severity, advancing age, and electrophysiological parameters can affect treatment outcome.     

Intraoperative electroneurography: management of ulnar neuropathy at the elbow

At the elbow the ulnar nerve may be compressed either in the retrocondylar groove or at the cubital tunnel. Optimal surgical therapy should be directed at the specific site of involvement. Intraoperative electroneurography performed in conjunction with 19 ulnar nerve explorations helped localize the precise site of compression. Of the primary procedures, abnormality was at the retrocondylar groove in 9, cubital tunnel in 4, both locations in 3, and at an unusual distal point in 1; 12 anterior subcutaneous transpositions, 4 cubital tunnel releases, and 1 distal decompression resulted. Intraoperative studies helped identify residual compression in two patients undergoing reexploration. Although routine electrodiagnosis may localize an ulnar neuropathy to the elbow, reliably separating retrocondylar from cubital tunnel compression is more difficult. Preoperatively, percutaneous serial short increment studies were more accurate than simple "inching" in predicting the site of compression.     

不同类型前置术治疗尺神经肘管卡压综合征

目的 对比不同类型前置术治疗尺神经肘管卡压综合征的临床疗效.方法 回顾性分析278例尺神经肘管卡压综合征病人的临床资料,按McGowan法分级后,随机行尺神经皮下前置术(皮下前置术)139例,"Z"字形改良肌下前置术(肌下前置术)139例.检测尺神经横截面积(CSA)、神经运动传导速度(MCV),感觉传导速度(SCV )、神经干动作电位(NAP)变化,比较两种术式的疗效.结果 McGowan Ⅰ级病人,术后 CSA,MCV,SCV,NAP均较术前明显改善(P <0.05),但两种术式间各参数和术后优良率差异均无统计学意义(P > 0.05).McGowan Ⅱ,Ⅲ级病人术后CSA,MCV,SCV,NAP均较术前明显改善(P<0.05),且两种术式间各参数和术后优良率差异均有统计学意义(P <0.05).结论 皮下前置术适于尺神经肘管卡压综合征McGowan Ⅰ级病人,而肌下前置术更适用于McGowan Ⅱ,Ⅲ级病人.     

The cubital tunnel syndrome: Treatment with simple decompression

Twelve patients with progressive cubital tunnel syndrome were treated with simple decompression of the ulnar nerve. The clinical and electrophysiological responses to treatment are described.     

Ulnar nerve lesions associated with the carpal tunnel syndrome

Electrophysiological studies were performed on median and ulnar nerves in 234 cases of carpal tunnel syndrome. Abnormalities of the ulnar nerve sensory action potential were found in 39·3% of cases. The amplitude of the ulnar nerve sensory action potential was related to the amplitude of the median nerve sensory action potential, and to the median nerve motor conduction velocity in the forearm. The findings suggest that in a significant proportion of patients with carpal tunnel syndrome, a more generalized subclinical neuropathy may be present.     

Neuromuscular ultrasound in common entrapment neuropathies

Neuromuscular ultrasound involves the use of high‐resolution ultrasound to image the peripheral nervous system of patients with suspected neuromuscular diseases. It complements electrodiagnostic studies well by providing anatomic information regarding nerves, muscles, vessels, tendons, ligaments, bones, and other structures that cannot be obtained with nerve conduction studies and electromyography. Neuromuscular ultrasound has been studied extensively over the past 10 years and has been used most often in the assessment of entrapment neuropathies. This review focuses on the use of neuromuscular ultrasound in 4 of the most common entrapment neuropathies: carpal tunnel syndrome, ulnar neuropathy at the elbow and wrist, and fibular neuropathy at the knee. Muscle Nerve 48:696–704, 2013     

Surgical treatment of common entrapment neuropathies in the upper limbs

Entrapment neuropathies of the upper extremity are common, debilitating conditions. Most patients with these neuropathies are readily diagnosed on purely clinical grounds and may be effectively managed with nonoperative measures. However, the broad differential diagnosis often necessitates electrodiagnostic testing and radiographic imaging to clarify the situation. This review focuses on three of the most common entrapment neuropathies in the upper limbs: carpal tunnel syndrome (median nerve entrapment at the wrist), cubital tunnel syndrome (ulnar nerve entrapment at the elbow), and radial tunnel syndrome (posterior interosseous nerve entrapment). Anatomical considerations, patient evaluation, indications for surgical intervention, options for surgical approaches, outcomes, and complications are discussed.     

Cubital Tunnel Syndrome, Associated With Synovial Chondromatosis

A 62-year-old female patient suffered from numbness and resting pain in the right ring and little fingers for 3 years. We confirmed cubital tunnel syndrome with electrodiagnostic study and performed the operation. We found seven firm consistent nodules, compressing the overlying the ulnar nerve, proximal to the medial epicondyle in the operation field. Histological finding showed synovial chondromatosis. We report a rare case of a patient with cubital tunnel syndrome caused by synovial chondromatosis.     

A reliable technique for ultrasound‐guided perineural injection in ulnar neuropathy at the elbow

Introduction: Ulnar neuropathy at the elbow (UNE) is a common peripheral compression neuropathy and, in most cases, occurs at 2 sites, the retroepicondylar groove or the cubital tunnel. With regard to a potential therapeutic approach with perineural corticosteroid injection, the aim of this study was to evaluate the distribution of injection fluid applied at a standard site. Methods: We performed ultrasound‐guided (US‐guided) perineural injections to the ulnar nerve halfway between the olecranon and the medial epicondyle in 21 upper limbs from 11 non‐embalmed cadavers. In anatomic dissection we investigated the spread of injected ink. Results: Ink was successfully injected into the perineural sheath of the ulnar nerve in all 21 cases (cubital tunnel: 21 of 21; retroepicondylar groove: 19 of 21). Conclusion: US‐guided injection between the olecranon and the medial epicondyle is a feasible and safe method to reach the most common sites of ulnar nerve entrapment. Muscle Nerve 56 : 237–241, 2017     

Electrophysiological studies in mild idiopathic carpal tunnel syndrome

Many techniques have been reported to improve the diagnosis of carpal tunnel syndrome (CTS), but there is no agreement on the diagnostic yield of these different methods. We used an electrophysiological protocol including the assessment of the orthodromic sensory conduction velocity of the median nerve along the carpal tunnel, comparison of median and ulnar sensory conduction between the ring finger and wrist, short segment incremental median sensory nerve conduction across the carpal tunnel recording from the III digit ('inching test'), the study of the refractory period of transmission (RPT) and calculation of the distoproximal ratio obtained by dividing the nerve conduction velocity in the median nerve between the third digit and the palm and between the palm and wrist in 41 patients with mild CTS (75 symptomatic hands) and in 45 control subjects. The distoproximal ratio calculation was the most sensitive technique (81%), but was also the least specific. The 'inching test', even though less sensitive, had the advantage of localising focal abnormalities of the median nerve along the carpal tunnel. RPT was abnormal in patients with recent symptoms. Combining the different techniques, an overall sensitivity of 92% was reached, 11% higher than the yield of the single best test suggesting that a multimodal approach could be useful. The best procedure for electrodiagnosis of mild CTS was to combine the median/ulnar comparison test with calculation of the disto-proximal ratio.     

Comparison of median and ulnar sensory nerve action potentials in the diagnosis of the carpal tunnel syndrome

Recording of median and ulnar digital sensory nerve action potentials in normal subjects showed that the ratio of the median (index finger) to ulnar (little finger) potential amplitude was consistently greater than one. In 15 patients with the carpal tunnel syndrome (seven bilateral) this ratio was found to be less than one for all but two of the 22 clinically affected hands, including three of the four hands with a normal motor latency to threshold stimulation and four of the five hands with a normal sensory conduction. It is concluded that the estimation of the ratio of the median to ulnar sensory potential amplitude is a sensitive test in the diagnosis of the carpal tunnel syndrome and is particularly useful in those patients who show a normal motor latency and sensory conduction.     

Usefulness of the median terminal latency ratio in the diagnosis of carpal tunnel syndrome

ObjectiveThe sensitivity of the median terminal latency (MTL) ratio was compared to that of standard conduction techniques for diagnosing carpal tunnel syndrome (CTS).MethodsWe analyzed 153 patients (274 hands) with clinically suspected CTS and 100 volunteers. Median motor conduction velocity and sensory nerve conduction velocity (MCV and SCV, respectively) were evaluated using traditional methods. The wrist–palm (W–P) MCV and two motor distal latency differences (LDs) between the median and ulnar nerves were measured. The MTL ratio was calculated by dividing the MTL-W by MTL-P. The ratio of distal to proximal conduction (disto-proximal ratio) was calculated.ResultsThe sensitivity of the motor nerve conducting technique was 77.7% in the W–P MCV, 72.6% in the median thenar–ulnar thenar LD, 63.9% in the median thenar–ulnar hypothenar LD, 59.9% in the MTL-P, 60.2% in the MTL-W, and 81.8% in the MTL ratio. The sensitivity of the median sensory nerve conduction method was 89.1% in the W-second F segment, 89.1% in the W-third F segment, 90.5% in the W–P segment, and 92.3% in the disto-proximal ratio of the third finger.ConclusionsThe disto-proximal ratio in the third finger was the most sensitive. Among the motor conduction studies, the MTL ratio was the most sensitive.SignificanceThese ratios can facilitate accurate diagnosis of patients with CTS.     

Axonal degeneration of the ulnar nerve secondary to carpal tunnel syndrome: fact or fiction?

The distribution of sensory symptoms in carpal tunnel syndrome is strongly dependent on the degree of electrophysiological dysfunction of the median nerve. The association between carpal tunnel syndrome and ulnar nerve entrapment is still unclear. In this study, we measured ulnar nerve function in 82 patients with carpal tunnel syndrome. The patients were divided into group I with minimal carpal tunnel syndrome (n = 35) and group II with mild to moderate carpal tunnel syndrome (n = 47) according to electrophysiological data. Sixty-one age- and sex-matched subjects without carpal tunnel syndrome were used as a control group. There were no significant differences in ulnar sensory nerve peak latencies or conduction velocities from the 4th and 5th fingers between patients with carpal tunnel syndrome and the control group. The ulnar sensory nerve action potential amplitudes from the 4th and 5th fingers were lower in patients with carpal tunnel syndrome than in the control group. The ratios of the ulnar sensory nerve action potential amplitudes from the 4th and 5th fingers were almost the same in patients with carpal tunnel syndrome as in the control group. These findings indicate that in patients with minimal to moderate carpal tunnel syndrome, there is some electrophysiological evidence of traction on the adjacent ulnar nerve fibers. The findings do not indicate axonal degeneration of the ulnar nerve.