Effect of dry needling on radial tunnel syndrome: A case report.

This case report describes a 45-year-old male who presented with chronic right lateral elbow pain managed unsuccessfully with conservative treatment that included anti-inflammatory medication, injection, massage, exercise, bracing, taping, electro-physical agents, and manual therapy. Diagnosis of radial tunnel syndrome (RTS) was based on palpatory findings, range of motion testing, resisted isometrics, and a positive upper limb neural tension test 2b (radial nerve bias). Conventionally, the intervention for this entrapment has been surgical decompression, with successful outcomes. This is potentially a first-time report, describing the successful management of RTS with dry needling (DN) using a recently published DN grading system. Immediate improvements were noted in all the outcome measures after the first treatment, with complete pain-resolution maintained at a 6-month follow-up. A model is proposed describing the mechanism by which DN could be used to intervene for nerve entrapment interfaces.

Effect of dry needling on cubital tunnel syndrome: Three case reports.

This case series describes three patients who presented with right medial elbow pain managed unsuccessfully with conservative treatment that included medication, massage, exercise therapy, ultrasound therapy, neurodynamic mobilization, and taping. Diagnosis of cubital tunnel syndrome was based on palpatory findings, a positive elbow flexion test, and a positive Tinel's sign. Conventionally, the intervention for this entrapment has been surgical decompression, with successful outcomes. This is potentially a first-time description of the successful management of cubital tunnel syndrome with dry needling (DN) using a recently published DN grading system. The patients were seen twice a week for 2 weeks with immediate improvements noted in all the outcome measures after the first treatment session. At discharge, they were pain-free and fully functional, which was maintained up to a 6-month follow-up.

Spike Timing-Dependent Plasticity in the Long-Latency Stretch Reflex Following Paired Stimulation from a Wearable Electronic Device.

The long-latency stretch reflex (LLSR) in human elbow muscles probably depends on multiple pathways; one possible contributor is the reticulospinal tract. Here we attempted to induce plastic changes in the LLSR by pairing noninvasive stimuli that are known to activate reticulospinal pathways, at timings predicted to cause spike timing-dependent plasticity in the brainstem. In healthy human subjects, reflex responses in flexor muscles were recorded following extension perturbations at the elbow. Subjects were then fitted with a portable device that delivered auditory click stimuli through an earpiece, and electrical stimuli around motor threshold to the biceps muscle via surface electrodes. We tested the following four paradigms: biceps stimulus 10 ms before click (Bi-10ms-C); click 25 ms before biceps (C-25ms-Bi); click alone (C only); and biceps alone (Bi only). The average stimulus rate was 0.67 Hz. Subjects left the laboratory wearing the device and performed normal daily activities. Approximately 7 h later, they returned, and stretch reflexes were remeasured. The LLSR was significantly enhanced in the biceps muscle (on average by 49%) after the Bi-10ms-C paradigm, but was suppressed for C-25ms-Bi (by 31%); it was unchanged for Bi only and C only. No paradigm induced LLSR changes in the unstimulated brachioradialis muscle. Although we cannot exclude contributions from spinal or cortical pathways, our results are consistent with spike timing-dependent plasticity in reticulospinal circuits, specific to the stimulated muscle. This is the first demonstration that the LLSR can be modified via paired-pulse methods, and may open up new possibilities in motor systems neuroscience and rehabilitation. SIGNIFICANCE STATEMENT: This report is the first demonstration that the long-latency stretch reflex can be modified by repeated, precisely timed pairing of stimuli known to activate brainstem pathways. Furthermore, pairing was achieved with a portable electronic device capable of delivering many more stimulus repetitions than conventional laboratory studies. Our findings open up new possibilities for basic research into these underinvestigated pathways, which are important for motor control in healthy individuals. They may also lead to paradigms capable of enhancing rehabilitation in patients recovering from damage, such as after stroke or spinal cord injury.

Ulnar nerve transposition at the elbow under local anesthesia: a patient satisfaction study.

BACKGROUND: Ulnar nerve decompression at the elbow traditionally requires regional or general anesthesia. We wished to assess the feasibility of performing ulnar nerve decompression and transposition at the elbow under local anesthesia. METHODS: We examined retrospectively the charts of 50 consecutive patients having undergone ulnar nerve entrapment surgery either under general or local anesthesia. Patients were asked to estimate pain on postoperative days 1 and 7 and satisfaction was assessed at 1 year. RESULTS: On day 1, pain was comparable among all groups. On day 7, pain scores were twice as high when transposition was performed under general anesthesia when compared with local anesthesia. Patient satisfaction was slightly increased in the local anesthesia group. These patients were significantly more willing to repeat the surgery. CONCLUSION: Ulnar nerve decompression and transposition at the elbow can be performed under local anesthesia without added morbidity when compared with general anesthesia.

The hypoalgesic effect of remote tactile sensory modulation on the mechanical sensitivity of trigger points: A randomized controlled study.

BACKGROUND: Sensitivity of the myofascial trigger point (MTrP) can be inhibited by electrical stimulation of remote site. However, it remains unclear whether remote pain control of the MTrP occurs in the same spinal segment or in the supraspinal system. OBJECTIVES: The aims of this study were to identify whether the remote pain control occurs in the spinal segment corresponding to the MTrP or in the supraspinal system. METHODS: Test subjects (n = 10) received transcutaneous electrical nerve stimulation for 5 minutes, whereas control subjects (n = 10) received no intervention. The threshold for tactile sensory modulation at the lateral elbow was assessed using Von Frey filaments. The pressure sensitivities of MTrPs in both the infraspinatus and upper trapezius muscles were quantified by algometry. Measurements were performed at baseline and 1 and 15 minutes after the intervention. RESULTS: Increases of the tactile threshold at the remote site decreased the sensitivity of the MTrP innervated by same spinal segment. However, no changes were observed at MTrP sites innervated by contralateral fibers or those from different spinal segment. CONCLUSION: MTrP sensitivity is more strongly affected by interventions at remote ipsilateral sites in the same spinal segment than by stimulation of extra-segmental sites.

Contralaterally controlled functional electrical stimulation for recovery of elbow extension and hand opening after stroke: a pilot case series study.

OBJECTIVE: The aims of this study were to determine whether patients with moderate-to-severe upper limb hemiplegia could use contralaterally controlled functional electrical stimulation at the arm and hand (Arm+Hand CCFES) at home and to evaluate the feasibility of Arm+Hand CCFES to reduce arm and hand motor impairment. DESIGN: With Arm+Hand CCFES, the paretic elbow and hand extensors were stimulated with intensities proportional to the degree of elbow extension and hand opening, respectively, of the contralateral unimpaired side. For 12 wks, four participants with chronic (≥6 mos) upper limb hemiplegia received ∼7 hrs per week of self-administered home-based stimulation-mediated elbow extension and hand opening exercise plus ∼2.5 hrs per week of therapist-supervised laboratory-based stimulation-assisted functional task practice. Assessments of upper limb impairment were made at pretreatment, posttreatment, and 1 mo after treatment. RESULTS: All four participants were able to use the Arm+Hand CCFES system at home either independently or with very minimal assistance from a caregiver. All four participants had increases in the Fugl-Meyer score (1-9 points) and the Wolf Motor Function Test (0.2-0.8 points) and varying degrees of improvement in maximum hand opening, maximum elbow extension, and simultaneous elbow extension and hand opening. CONCLUSIONS: Arm+Hand CCFES can be successfully administered in stroke patients with moderate-to-severe impairment and can reduce various aspects of upper limb impairment. A larger efficacy study is warranted.

Startle reveals independent preparation and initiation of triphasic EMG burst components in targeted ballistic movements.

Muscles involved in rapid, targeted movements about a single joint often display a triphasic [agonist (AG1)-antagonist (ANT)-agonist (AG2)] electromyographic (EMG) pattern. Early work using movement perturbations suggested that for short movements, the entire EMG pattern was prepared and initiated in advance (Wadman WJ, Dernier van der Gon JJ, Geuze RH, Mol CR. J Hum Mov Stud 5: 3-17, 1979), whereas more recent transcranial magnetic stimulation evidence indicates that the ANT may be programmed separately (MacKinnon CD, Rothwell JC. J Physiol 528: 633-645, 2000) with execution of the bursts occurring serially (Irlbacher K, Voss M, Meyer BU, Rothwell JC. J Physiol 574: 917-928, 2006). The purpose of the current study was to investigate the generation of triphasic EMG bursts for movements of different amplitudes. In experiment 1, participants performed rapid elbow extension movements to 20° and 60° targets, and on some trials, a startling acoustic stimulus (SAS), which is thought to trigger prepared motor commands at short latency, was delivered at the onset of AG1. For short movements, this perturbation elicited ANT and AG2 early, suggesting the agonist and antagonist bursts may have been programmed independently. In contrast, the same manipulation did not disrupt EMG timing parameters for the long movements, raising the possibility that ANT and AG2 were not fully programmed in advance of movement onset. In experiment 2, an SAS was delivered later in the movement, which produced early onset of both ANT and AG2. We propose that the triphasic pattern is executed serially but believe the trigger signal for initiating the ANT burst occurs not in relation to the AG1 burst, but rather in close temporal proximity to the expected onset of ANT.

The differential role of motor cortex in stretch reflex modulation induced by changes in environmental mechanics and verbal instruction.

The motor cortex assumes an increasingly important role in higher mammals relative to that in lower mammals. This is true to such an extent that the human motor cortex is deeply involved in reflex regulation and it is common to speak of "transcortical reflex loops." Such loops appear to add flexibility to the human stretch reflex, once considered to be immutable, allowing it to adapt across a range of functional tasks. However, the purpose of this adaptation remains unclear. A common proposal is that stretch reflexes contribute to the regulation of limb stability; increased reflex sensitivity during tasks performed in unstable environments supports this hypothesis. Alternatively, before movement onset, stretch reflexes can assist an imposed stretch, opposite to what would be expected from a stabilizing response. Here we show that stretch reflex modulation in tasks that require changes in limb stability is mediated by motor cortical pathways, and that these differ from pathways contributing to reflex modulation that depend on how the subject is instructed to react to an imposed perturbation. By timing muscle stretches such that the modulated portion of the reflex occurred within a cortical silent period induced by transcranial magnetic stimulation, we abolished the increase in reflex sensitivity observed when individuals stabilized arm posture within a compliant environment. Conversely, reflex modulation caused by altered task instruction was unaffected by cortical silence. These results demonstrate that task-dependent changes in reflex function can be mediated through multiple neural pathways and that these pathways have task-specific roles.

Functional restoration of elbow extension after spinal-cord injury using a neural network-based synergistic FES controller.

Individuals with a C5/C6 spinal-cord injury (SCI) have paralyzed elbow extensors, yet retain weak to strong voluntary control of elbow flexion and some shoulder movements. They lack elbow extension, which is critical during activities of daily living. This research focuses on the functional evaluation of a developed synergistic controller employing remaining voluntary elbow flexor and shoulder electromyography (EMG) to control elbow extension with functional electrical stimulation (FES). Remaining voluntarily controlled upper extremity muscles were used to train an artificial neural network (ANN) to control stimulation of the paralyzed triceps. Surface EMG was collected from SCI subjects while they produced isometric endpoint force vectors of varying magnitude and direction using triceps stimulation levels predicted by a biomechanical model. ANNs were trained with the collected EMG and stimulation levels. We hypothesized that once trained and implemented in real-time, the synergistic controller would provide several functional benefits. We anticipated the synergistic controller would provide a larger range of endpoint force vectors, the ability to grade and maintain forces, the ability to complete a functional overhead reach task, and use less overall stimulation than a constant stimulation scheme.

A review of compressive ulnar neuropathy at the elbow.

OBJECTIVE: To review the anatomy, etiology, and symptoms associated with compressive ulnar neuropathy at the elbow and to discuss the diagnosis and treatment of this condition. DATA SOURCE: The following were searched for information relevant to cubital tunnel syndrome: MEDLINE, WorldCat, and Index to Chiropractic Literature. RESULTS: Cubital tunnel syndrome is the second most common nerve compression syndrome of the upper extremity. Clinical features of this syndrome are described along with electrodiagnostic techniques that can be used to provide evidence concerning the probable location, character, and severity of the lesion affecting the ulnar nerve. Conservative treatment of cubital tunnel syndrome is recommended for patients with intermittent symptoms and without changes in cutaneous sensation or muscle atrophy. CONCLUSION: A definitive diagnosis can best be made using clinical tests along with nerve conduction studies and electromyography, conservative treatment can be effective in treating this neuropathy in mild cases; in moderate or severe cases, surgery may be necessary.

Double peak sensory responses at submaximal stimulation.

OBJECTIVE: The objective of the study was to obtain knowledge about the different physiological situations where a double peak sensory response normally occurs and to better understand the significance of this particular sensory response. METHODS: In 14 healthy subjects, conventional orthodromic sensory nerve conduction studies were performed on the median and ulnar nerves using submaximal stimulation. Various stimulus strengths, polarity, electrode positions and local anaesthesia were used to clarify the generation of the two peaks. RESULTS: When the cathode and the anode were independently moved in distal direction, the first and the second peaks moved distally, respectively. This occurred for conventional and reversed position of the electrode. Anodal stimulation was ineffective after local skin anaesthesia. CONCLUSIONS: Our experiments seem to indicate that the double response represents the two stimulation sites, under the cathode and the anode, respectively. Obviously the double response can only occur if different axons are stimulated under the two poles. The cathode and the anode do not seem preferably to stimulate fast or slow axons. Studies with superficial anaesthesia may indicate that the cathode stimulates the sensory nerve directly while the anode mainly stimulates superficial structures, skin sensory receptors or intradermal nerve terminals.

A real-time EMG-driven virtual arm.

An EMG-driven virtual arm is being developed in our laboratories for the purposes of studying neuromuscular control of arm movements. The virtual arm incorporates the major muscles spanning the elbow joint and is used to estimate tension developed by individual muscles based on recorded electromyograms (EMGs). It is able to estimate joint moments and the corresponding virtual movements, which are displayed in real-time on a computer screen. In addition, the virtual arm offers artificial control over a variety of physiological and environmental conditions. The virtual arm can be used to examine how the neuromuscular system compensates for the partial or total loss of a muscle's ability to generate force as might result from trauma or pathology. The purpose of this paper is to describe the design objectives, fundamental components and implementation of our real-time, EMG-driven virtual arm.

Effect of stimulation in the ventral intermediate nucleus of the thalamus on limb control in Parkinson's disease: a case study.

This study focuses on upper extremity strength and movement control in a patient with Parkinson's disease who had stimulating electrodes surgically implanted in the ventral intermediate nucleus (VIM) of the left thalamus. We examined torque generation and control of movement distance in single degree-of-freedom elbow movements under three different stimulation conditions: (a) no stimulation, (b) high stimulation, in which tremor was minimized but there was also tingling and perceived weakness, and (c) moderate stimulation, in which tremor was partially reduced, but there was also a subjective sense of increased strength compared with the high-stimulation condition. The patient's ability to generate both steady torque and rapid movements was poorest with no stimulation. The patient generated the largest torques with moderate stimulation and performed the fastest movements with high stimulation. However, even with tremor minimized, the patient's electromyogram (EMG) burst patterns were not typical of those of neurologically healthy subjects, although the movements were clearly improved.

Regional anesthesia in the upper extremity.

We have attempted to formulate a guide for surgeons who operate frequently on the hand and upper extremity and who wish to learn how to provide their own local anesthesia. The methods that we have presented are those that work well in our hands and are in frequent use in our practices. We recognize very clearly that there are other methods and that these work well for other surgeons. The method itself is not of great importance (given that it is safe and effective), but the philosophy of learning is. By observation and by practice, the surgeon will gain further mastery of his specialty; we feel strongly that local anesthesia is as much or more a part of surgery than it is of any other specialty. Reading and observation are important. Dissection, whether in the operating room as part of a surgical procedure or in the anatomy laboratory or morgue, is of great benefit in learning the whereabouts and relationships of the nerves that are to be blocked. In the end, however, the surgeon simply must try the various blocks himself on his own patients. Failure is not a calamity; we have tried to emphasize that there are ways to recover with a reasonable degree of grace. The worst calamity is not to learn, not become facile with techniques that are so ideally suited to surgery in the upper extremity.