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Concept: Ulnar nerve entrapment


To evaluate T2-signal of high-resolution MRI in distal ulnar nerve branches at the wrist as diagnostic sign of guyon’s-canal-syndrome (GCS).

Concepts: Forearm, Ulnar nerve, Carpal tunnel, Ulnar artery, Ulnar nerve entrapment, Ulnar canal, Guyon's canal syndrome


Purpose: Snapping ulnar nerve syndrome (dislocation of the ulnar nerve over the medial epicondyle) is one of many causes of ulnar neuropathy at the elbow. This preliminary study was performed to search for sonographic signs suggesting the presence of this condition.Methods and Materials: We retrospectively investigated 11 patients with snapping ulnar nerve syndrome (SNAP) in comparison with an age-matched group of 20 patients with idiopathic cubital tunnel syndrome (SNU). Patients were grouped according to the presence of paretic or merely sensory deficits. Nerve cross section area (CSA) and thickness of outer epineurium (ET) was measured and correlated with neurological findings. Statistical differences were evaluated with the Mann-Whitney U-Test.Results: 5 SNAP (10 SNU) patients had sensory symptoms only, 6 SNAP (10 SNU) patients had paretic deficits. CSA in sensory SNU was 0.14 cm2, in paretic SNU 0.19 cm2, in sensory SNAP 0.15 cm2 and in paretic SNAP 0.14 cm2. ET in sensory SNU was 0.85 mm, 0.8 mm in paretic SNU, 1.05 mm in sensory SNAP and 1.1 in paretic SNAP. Differences in CSA were not significant depending on symptoms or group, differences in ET were not significant depending on symptoms but on group (SNAP versus SNU) at α = 0.05.Conclusion: A thickened, hyperechoic outer epineurium in a patient with ulnar neuropathy at the elbow might be a statistically significant differential feature of snapping ulnar nerve syndrome and should be involved in a further functional sonographic evaluation during flexion/extension of the elbow.

Concepts: Statistics, Statistical significance, Humerus, Upper limb anatomy, Ulnar nerve, Median nerve, Cubital tunnel, Ulnar nerve entrapment


OBJECTIVE: This study aims to investigate the involvement of the peripheral nervous system in Ehlers-Danlos syndromes/hypermobility type patients with particular attention to entrapment syndromes. METHODS: We consecutively enrolled Ehlers-Danlos syndromes/hypermobility type patients. Patients underwent clinical, neurophysiological and ultrasound evaluations. Dynamic ultrasound evaluation was also performed in healthy subjects as control group. RESULTS: Fifteen Ehlers-Danlos syndromes/hypermobility type patients and fifteen healthy subjects were enrolled. Most of patients presented tingling, numbness, cramps in their hands or feet. Clinical evaluation was normal in all patients. One patient was affected with carpal tunnel syndrome and one with ulnar nerve entrapment at elbow. One patient had an increased and hypoechoic ulnar nerve at elbow at ultrasound evaluation. Dynamic ultrasound evaluation of ulnar nerve at elbow showed, in patients, twelve subluxations and three luxations. In the control group dynamic evaluation showed one case of ulnar nerve luxation. CONCLUSION: Statistical analysis showed a significant difference in the occurrence of ulnar nerve subluxation and luxation between patients and control subjects. SIGNIFICANCE: The study shows an inconsistency between symptoms and neurophysiological and ultrasound evidences of focal or diffuse nerve involvement. The high prevalence of ulnar nerve subluxation/luxation at elbow in Ehlers-Danlos syndromes/hypermobility type patients could be explained by the presence of Osborne ligament laxity.

Concepts: Nervous system, Syndromes, Paresthesia, Wrist, Carpal tunnel, Carpal tunnel syndrome, Median nerve, Ulnar nerve entrapment


Endoscopic cubital tunnel release was originally described in 1989 by Tsai, and his technique has been modified by other surgeons including Mirza and Cobb. In 2006, Hoffmann and Siemionow described an endoscopic technique quite different from Tsai’s original description. Instead of working from the “inside out,” Hoffmann’s technique is performed through an incision similar to that which would be used for an in situ release of the ulnar nerve. The main difference being that the nerve can be explored and decompressed 10 cm proximal and distal to the arcuate ligament as the surgeon looks down on the nerve and the surrounding tissues while viewing the anatomy through a camera attached to a soft tissue endoscope that is inserted in the wound. The arcuate (Osborne’s) ligament is released under direct vision much like a standard in situ decompression. Using a blunt dissection instrument, a workspace is created proximally and distally to the cubital tunnel. Next an illuminated speculum is introduced, the nerve is directly visualized between 4 and 5 cm proximal and distal to the cubital tunnel, and potential compressive forearm fasciae or fibrous bands are released. Finally, a 15-cm, 30° soft tissue endoscope is introduced into the incision, and viewing the internal anatomy on a video monitor, the decompression continues using longer scissors. Any potential bleeding is controlled with a long bayonet bipolar cautery. The authors discuss indications, contraindications, and the surgical technique. Postoperative management and associated complications are also discussed.

Concepts: Surgery, Tissues, Surgeon, Ulnar nerve, Ulnar artery, Cubital tunnel, Ulnar nerve entrapment, Cauterization


BACKGROUND:: Both open and retractor-endoscopic ulnar nerve decompression have been shown to yield good results; a comparative evaluation of the techniques is lacking. Objective: To compare the results of open and endoscopic surgery in cubital tunnel syndrome. METHODS:: One hundred fourteen patients undergoing open (n=59) and endoscopic (n=55) decompression of the ulnar nerve for CbTS were retrospectively compared. The long-term and the short-term outcomes were compared with respect to the time until return to full activity and the duration of postoperative pain. Additionally, matched pairs between the two groups were chosen for analysis (n= 34). RESULTS:: Long-term results in the open versus endoscopic groups, respectively, were: 54.2% vs 56.4%- excellent, 23.8% vs 32.7%- good, 20.3% vs 9.1%- fair, and 1.7% vs 1.8%- poor. For the matched pairs, the results returned similar significance levels (p=0.84). The times until return to full activity in the open versus the endoscopic groups were: 18.6% vs 76.4% (2-7 days), 55.9% vs 10.9% (7-14 days), and 25.4% vs 12.7% (> 14 days) (p<0.001 between non-matched & matched pairs). The durations of postoperative pain in the open versus the endoscopic groups were: 45.8% vs 67.3% (1-3 days), 42.5% vs 25.4% (3-10 days), and 11.7% vs 7.3% (> 10 days) (p=0.04 non-matched and p=0.05 matched pairs). CONCLUSION:: There are no significant differences in long-term outcomes after open and retractor-endoscopic in situ decompressions of the ulnar nerve in cubital tunnel syndrome. The short-term results are significantly better in endoscopic surgery.

Concepts: Time, Cohort study, Statistical significance, Ulnar nerve, Median nerve, Ulnar artery, Cubital tunnel, Ulnar nerve entrapment


Study Design Systematic review with meta-analysis. Background Neural mobilization (NM) or neurodynamics is a movement-based intervention aimed at restoring the homeostasis in and around the nervous system. The current level of evidence for NM is largely unknown. Objectives To determine the efficacy of NM for musculoskeletal conditions with a neuropathic component. Methods Databases were searched for randomised trials investigating the effect of NM for neuro-musculoskeletal conditions. Standard methods for article identification, selection and quality appraisal were used. Where possible, studies were pooled for meta-analysis. Primary outcomes were pain, disability and function. Results Forty studies were included in this review, of which 17 had a low risk of bias. Meta-analyses could only be performed on self-reported outcomes. For chronic low back pain, disability (Oswestry (0-50): mean difference -9.26; 95%CI: -14.50 - -4.01; p=0.0001) and pain (Intensity (0-10): mean difference -1.78; 95%CI: -2.55 - -1.01; p=0.0001) improved following NM. For chronic neck-arm pain, pain improved (Intensity (0-10): mean difference -1.89; 95%CI: -3.14 - -0.64; p=0.0003) following NM. For carpal tunnel syndrome, NM was not effective for most clinical outcomes (p>0.11), but showed positive neurophysiological effects (e.g., reduced intraneural oedema). Due to a scarcity of studies or conflicting results, the effect of NM remains uncertain for various conditions, such as post-operative low back pain, cubital tunnel syndrome and lateral epicondylalgia. Conclusion This review reveals benefits of NM for back and neck pain, but the effect of NM for other conditions remains unclear. Due to the limited evidence and varying methodological quality, conclusions may change over time. Level of Evidence Level 1. J Orthop Sports Phys Ther, Epub 13 Jul 2017. doi:10.2519/jospt.2017.7117.

Concepts: Nervous system, Low back pain, Evidence-based medicine, Randomized controlled trial, Neuroscience, Meta-analysis, Carpal tunnel syndrome, Ulnar nerve entrapment


The aim of the present study was to investigate a new clinical classification of cubital tunnel syndrome that provides an improved basis for the clinical diagnosis and treatment of the disease. Retrospective analysis was performed on 341 patients with cubital tunnel syndrome. Based on the etiology, signs and symptoms, neurophysiological tests and computed tomography (CT) imaging, a new clinical classification was proposed. The patients enrolled in the study were treated according to the new classification. According to the new classification, cubital tunnel syndrome cases were divided into types I-IV. Treatment for patients with type I consisted of rest, immobilization or physiotherapy, while patients with type II received simple ulnar neurolysis. Type III patients underwent ulnar neurolysis with expansion of the ulnar nerve sulcus or ulnar nerve anterior transposition surgery. Type IV patients represented a subgroup of cubital tunnel syndrome cases caused by factors other than degenerative joint diseases, including cysts, tumors, traumatic fracture, deformity and elbow deformity. Patients of this type received appropriate surgical treatment according to the specific etiology. Based on previous classifications that relied on sensation and strength symptoms, a new clinical classification of elbow tunnel syndrome has been established in the present study that adopts a CT imaging evaluation index. The new classification is reasonable, simple and practical, and therapies based on this classification are more targeted than those based on previous classifications.

Concepts: Medicine, The Canon of Medicine, Humerus, Ulnar nerve, Median nerve, Ulnar artery, Cubital tunnel, Ulnar nerve entrapment


Carpal tunnel syndrome, a median nerve entrapment neuropathy, is characterized by sensorimotor deficits. Recent reports have shown that this syndrome is also characterized by functional and structural neuroplasticity in the primary somatosensory cortex of the brain. However, the linkage between this neuroplasticity and the functional deficits in carpal tunnel syndrome is unknown. Sixty-three subjects with carpal tunnel syndrome aged 20-60 years and 28 age- and sex-matched healthy control subjects were evaluated with event-related functional magnetic resonance imaging at 3 T while vibrotactile stimulation was delivered to median nerve innervated (second and third) and ulnar nerve innervated (fifth) digits. For each subject, the interdigit cortical separation distance for each digit’s contralateral primary somatosensory cortex representation was assessed. We also evaluated fine motor skill performance using a previously validated psychomotor performance test (maximum voluntary contraction and visuomotor pinch/release testing) and tactile discrimination capacity using a four-finger forced choice response test. These biobehavioural and clinical metrics were evaluated and correlated with the second/third interdigit cortical separation distance. Compared with healthy control subjects, subjects with carpal tunnel syndrome demonstrated reduced second/third interdigit cortical separation distance (P < 0.05) in contralateral primary somatosensory cortex, corroborating our previous preliminary multi-modal neuroimaging findings. For psychomotor performance testing, subjects with carpal tunnel syndrome demonstrated reduced maximum voluntary contraction pinch strength (P < 0.01) and a reduced number of pinch/release cycles per second (P < 0.05). Additionally, for four-finger forced-choice testing, subjects with carpal tunnel syndrome demonstrated greater response time (P < 0.05), and reduced sensory discrimination accuracy (P < 0.001) for median nerve, but not ulnar nerve, innervated digits. Moreover, the second/third interdigit cortical separation distance was negatively correlated with paraesthesia severity (r = -0.31, P < 0.05), and number of pinch/release cycles (r = -0.31, P < 0.05), and positively correlated with the second and third digit sensory discrimination accuracy (r = 0.50, P < 0.05). Therefore, reduced second/third interdigit cortical separation distance in contralateral primary somatosensory cortex was associated with worse symptomatology (particularly paraesthesia), reduced fine motor skill performance, and worse sensory discrimination accuracy for median nerve innervated digits. In conclusion, primary somatosensory cortex neuroplasticity for median nerve innervated digits in carpal tunnel syndrome is indeed maladaptive and underlies the functional deficits seen in these patients.

Concepts: Brain, Magnetic resonance imaging, Somatosensory system, Ulnar nerve, Carpal tunnel, Carpal tunnel syndrome, Median nerve, Ulnar nerve entrapment


Cubital tunnel syndrome is the second most common upper extremity compressive neuropathy. In recent years, rates of surgical treatment have increased, and the popularity of in situ decompression has grown. Nonsurgical treatment, aiming to decrease both compression and traction on the ulnar nerve about the elbow, is successful in most patients with mild nerve dysfunction. Recent randomized controlled trials assessing rates of symptom resolution and ultimate success have failed to identify a preferred surgical procedure. Revision cubital tunnel surgery, most often consisting of submuscular transposition, may improve symptoms. However, ulnar nerve recovery after revision cubital tunnel surgery is less consistent than that after primary cubital tunnel surgery.

Concepts: Hospital, Surgery, Anesthesia, Upper limb anatomy, Ulnar nerve, Median nerve, Cubital tunnel, Ulnar nerve entrapment


We describe an unusual case of ulnar nerve compression (cubital tunnel syndrome) caused by synovial protrusion in primary synovial chondromatosis of the elbow in a 59-year-old man. Magnetic resonance imaging is a useful tool for diagnosing this rare condition. Surgical excision of the intra-articular multiple loose bodies and ulnar nerve decompression were performed. The clinician should be aware of primary synovial chondromatosis as one of the causative factors of cubital tunnel syndrome.

Concepts: Surgery, Nuclear magnetic resonance, Magnetic resonance imaging, Ulnar nerve, Median nerve, Ulnar artery, Cubital tunnel, Ulnar nerve entrapment