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PubMed1975

Neurotological studies on the role of the sympathetic nervous system in the formation of traumatic vertigo of cervical origin.

To test the validity of the hypothesis that irritation of the cervical sympathetic nerves is a cause of hypertonicity of the cervical soft supporting tissues, especially the deep nuchal muscles, and that this hypertonicity is a cause of traumatic vertigo of cervical origin, we examined 44 vertigo cases with whiplash injury by testing equilibrium function and EMG discharges from the neck before and after administration of drugs affecting the sympathetic receptors. The results obtained were as follows: 1. Administration of iso-proterenol (beta-receptor stimulant) caused a significant increase in the EMG's from the injured neck muscles, in parallel with increased impairment of the righting reflex. The blindfolded vertical writing test showed the appearance or intensification of ataxia or deviation in writing when this drug was given. In contrast, administration of propranolol (beta-receptor depressor) had the opposite effects on the EMG's, the righting reflex and blindfolded vertical writing. Furthermore, the resulting changes in the EMG's and equilibrium functions were parallel with alterations in subjects' complaints, i.e., increase or decrease in neck pain and vertigo. 2. Administration of drugs affecting the alpha receptors, such as noradrenaline (alpha-receptor stimulant) and phentolamine (alpha-receptor depressor) had no appreciable effect on the EMG's, equilibrium function or the subjects' complaints. These results show that in vertigo due to whiplash injury hypertonicity of the cervical erector muscles can be induced sympathetically, and that this hypertonicity is based on over-excitement of beta receptors in the injured neck muscles, which results in vertigo of cervical origin.

Adolescent↗

PubMed2005

Gender differences in head-neck segment dynamic stabilization during head acceleration.

PURPOSE: Recent epidemiological research has revealed that gender differences exist in concussion incidence but no study has investigated why females may be at greater risk of concussion. Our purpose was to determine whether gender differences existed in head-neck segment kinematic and neuromuscular control variables responses to an external force application with and without neck muscle preactivation. METHODS: Forty (20 females and 20 males) physically active volunteers participated in the study. The independent variables were gender, force application (known vs unknown), and force direction (forced flexion vs forced extension). The dependent variables were kinematic and EMG variables, head-neck segment stiffness, and head-neck segment flexor and extensor isometric strength. Statistical analyses consisted of multiple multivariate and univariate analyses of variance, follow-up univariate analyses of variance, and t-tests (P < or = 0.05). RESULTS: Gender differences existed in head-neck segment dynamic stabilization during head angular acceleration. Females exhibited significantly greater head-neck segment peak angular acceleration (50%) and displacement (39%) than males despite initiating muscle activity significantly earlier (SCM only) and using a greater percentage of their maximum head-neck segment muscle activity (79% peak activity and 117% muscle activity area). The head-neck segment angular acceleration differences may be because females exhibited significantly less isometric strength (49%), neck girth (30%), and head mass (43%), resulting in lower levels of head-neck segment stiffness (29%). CONCLUSION: For our subject demographic, the results revealed gender differences in head-neck segment dynamic stabilization during head acceleration in response to an external force application. Females exhibited significantly greater head-neck segment peak angular acceleration and displacement than males despite initiating muscle activity earlier (SCM only) and using a greater percentage of their maximum head-neck segment muscle activity.

Acceleration↗

PubMed2006

Isometric strength of the cervical flexor, extensor, and rotator muscles in 220 healthy females aged 20 to 59 years.

STUDY DESIGN: Cross-sectional descriptive study. OBJECTIVES: To determine the maximal isometric strength of the flexor, extensor, and rotator muscles of the cervical spine in healthy females of working age to document reference values for diagnostic and rehabilitation purposes. BACKGROUND: Reference values for the isometric strength of the cervical muscles have often been based on small samples. To date, reference values for rotator muscles of the cervical spine have not been published. METHODS AND MEASURES: The group consisted of 220 volunteer healthy females in 4 age groups (20-29 years, n = 57; 30-39 years, n = 51; 40-49 years, n = 51; 50-59 years, n = 61) from Jyadskyla, Finland. Isometric cervical muscle strength in flexion, extension, and rotation was evaluated with a specially designed measurement system. RESULTS: Across all age groups, mean (+/-SD) maximal isometric neck strength was 73.8 +/- 20.0 N in flexion and 190.8 +/- 31.3 N in extension. Mean (+/-SD) rotation strength was 8.1 +/- 2.3 Nm to the right and 7.9 +/- 2.3 Nm to the left. Absolute strength values did not differ among the age groups. A weak but significant correlation between body mass and neck flexion (r = 0.31, P<.01) and extension (r = 0.25, P<.01) strength was found. Intratester reliability varied from 0.87 to 0.96. CONCLUSIONS: Women aged 20 to 59 years appear to have similar absolute isometric neck muscle strength levels. Thus these values can be used as reference for the working-age female population.

Adult↗

PubMed2001

Influence of head-down and lateral decubitus neck flexion on heart rate variability.

The purpose of this study was to examine the response of heart rate variability (HRV), a noninvasive index of autonomic control, to head-down neck flexion (HDNF), which engages both otoliths and neck muscle afferents, and to lateral decubitus neck flexion (LNF), in which neck afferents are activated, whereas otolith afferent input is not. HRV and forearm blood flow were evaluated in participants lying prone, during HDNF, lying in the lateral decubitus position, and during LNF. Compared with the prone position, HDNF resulted in lower high-frequency (46.9 +/- 7.1 vs. 62.3 +/- 6.2) and higher low-frequency (53.1 +/- 7.1 vs. 37.7 +/- 6.2) power, expressed as normalized units, along with higher low-frequency-to-high-frequency ratio (1.65 +/- 0.3 vs. 0.78 +/- 0.2), whereas LNF resulted in no alterations in HRV indexes. Furthermore, there were no significant differences in forearm blood flow or vascular resistance among any of the positions. Our data suggest that otolith organs influence autonomic modulation of the heart, supporting previous studies reporting that HDNF elicits increased sympathetic outflow. These data further suggest that HDNF results in a parasympathetic withdrawal from the heart in addition to sympathetic activation.

Adult↗

PubMed1994

Axial myoclonus mediated by the propriospinal tract: a case report.

We describe a patient with axial myoclonus. Myoclonus first occurred in the upper abdominal muscle and spread up to the neck muscle and down to the lower abdominal muscle. Physiological studies of the jerks revealed that the myoclonus arose in the thoracic spinal cord and spread slowly up and down the spinal cord at about 3 m/s. We conclude that the myoclonus is mediated by the propriospinal tract.

Adult↗

PubMed1979

Statistical analysis of an urban population of 236 patients with head and neck pain. Part II. Patient symptomatology.

A large group of patients (236) was examined for Myofascial Pain Dysfunction Syndrome. The symptoms of the patients were recorded, using as a guide the classic parameters of pain and tenderness to the head and neck muscles and temporomandibular joint, joint sounds, and limited function. Our basic data were similar to those of other studies. The significant difference of this study is the detail with which the symptoms were studied. The relationships of suspected etiology and symptoms were compared and discussed. This paper is the second of a three part series. The first part dealt with the demographic profile of our patient population. The third part will present the data dealing with treatment modalities and relief.

Adolescent↗

PubMed1989

[Response properties of the neurons in the cervical cord to stimulation of the inferior alveolar nerve in the cat].

The purpose of this study was to investigate the neuronal mechanisms of the clinical symptoms of unusual muscle stiffness and/or pain in the neck and shoulder sometimes observed in patients suffering from chronic pulpal or periodontal diseases. Physiological properties of the neurons responding to the inferior alveolar nerve stimulation (inferior alveolar nerve driven-neurons: IANDNs) were studied by recording single unit activities in the upper cervical cord in cats anesthetized with alpha-chloralose. The results were as follows: (1) IANDNs were widely distributed from the dorsal horn to the ventral horn in the gray matter of the cervical cord (C2 and C3). (2) IANDNs were subdivided into two types of neurons based on the latencies of the spike responses: fast-type (F-type) (n = 60) and slow-type (S-type) (n = 101). (3) Two possible pathways from the inferior alveolar nerve to the cervical spinal cord participating in these spike responses were assumed: one was through the trigeminal spinal nucleus and the other through Probst's tract by way of the trigeminal mesencephalic nucleus. These results suggest that the impulses originating from dental inflammatory loci might drive IANDNs in C2 or C3 and that their activities may evoke contraction of the neck muscles, resulting in their stiffness and cervical back pain.

Animals↗

PubMed1998

Neck semispinalis capitis muscle size in sitting and prone positions measured by real-time ultrasonography.

OBJECTIVE: To examine the reliability of measurements of semispinalis capitis muscle (SECM) cross-sectional area (CSA) in prone and sitting positions, and to compare the muscle size in these two positions. DESIGN: Semispinalis capitis CSA was measured twice a day on two successive days with a real-time ultrasound apparatus. SUBJECTS: Eighteen males (aged 19-34 years) and 28 females (aged 19-34 years) were studied for the reliability test. Seven males and 12 females were randomly selected to compare SECM size in sitting and prone positions. RESULTS: The intraclass correlation coefficient (ICC) for repeatability measurements was r = 0.98 for the two positions. The correlation of the CSA in sitting and in prone positions was r = 0.93 (p < 0.01). There were no significant differences between CSA, linear dimensions and shape ratio of SECM in the two positions. CONCLUSIONS: In this study SECM ultrasonography appeared to be an accurate method in both positions, and position as such had no significant effects on the SECM cross-sectional size. Such accuracy allows neck muscle evaluation in clinical diagnosis and in follow-up studies during neck rehabilitation programmes.

Adult↗

PubMed1995

EMG levels in children who suffer from severe headache.

Very little information exists about the physiology of pediatric headache and in particular, the role that skeletal musculature plays in the genesis of head pain. This study explored EMG levels in the neck and forehead in a group of 12 children who complained of severe headache. Comparisons were made with a matched group of 12 children who were headache-free. Results suggested that children with headache suffer from very tense neck muscles which may reflect high levels of anxiety.

Adolescent↗

PubMed1998

Neck afferents and muscle sympathetic activity in humans: implications for the vestibulosympathetic reflex.

We have shown previously that head-down neck flexion (HDNF) in humans elicits increases in muscle sympathetic nerve activity (MSNA). The purpose of this study was to determine the effect of neck muscle afferents on MSNA. We studied this question by measuring MSNA before and after head rotation that would activate neck muscle afferents but not the vestibular system (i.e., no stimulation of the otolith organs or semicircular canals). After a 3-min baseline period with the head in the normal erect position, subjects rotated their head to the side (approximately 90%) and maintained this position for 3 min. Head rotation was performed by the subjects in both the prone (n = 5) and sitting (n = 6) positions. Head rotation did not elicit changes in MSNA. Average MSNA, expressed as burst frequency and total activity, was 13 +/- 1 and 13 +/- 1 bursts/min and 146 +/-34 and 132 +/- 27 units/min during baseline and head rotation, respectively. There were no significant changes in calf blood flow (2.6 +/- 0.3 to 2.5 +/- 0.3 ml.100 ml-1.min-1, n = 8) and calf vascular resistance (39 +/- 4 to 41 +/- 4 units; n = 8). Heart rate (64 +/- 3 to 66 +/- 3 beats/min; P = 0.058) and mean arterial pressure (90 +/- 3 to 93 +/- 3; P < 0.05) increased slightly during head rotation. Additional neck flexion studies were performed with subjects lying on their side (n = 5), MSNA, heart rate, and mean arterial pressure were unchanged during this maneuver, which also does not engage the vestibular system. HDNF was tested in 9 of the 13 subjects. MSNA was significantly increased by 79 +/- 12% (P < 0.001) during HDNF. These findings indicate that neck afferents activated by horizontal neck rotation or flexion in the absence of significant force development do not elicit changes in MSNA. These findings support the concept that HDNF increases MSNA by the activation of the vestibular system.

Adult↗

PubMed1999

The effect of jaw clenching on the electromyographic activities of 2 neck and 2 trunk muscles.

AIMS: Symptoms of jaw dysfunction are often associated with neck muscle dysfunction or other musculoskeletal problems. This study attempted to quantify the effect of jaw clenching on the electromyographic (EMG) activity of certain neck, trunk, and jaw muscles. METHODS: The authors recorded EMG muscle activity in the sternocleidomastoid, trapezius, paravertebral, and rectus abdominis muscles in 10 university students at rest and during strong jaw clenching in supine and sitting positions. RESULTS: In both positions, jaw clenching resulted in increases in neck muscle activity ranging from 7.6 to 33 times resting muscle activity; for the trunk muscles, the increases ranged from 1.4 to 3.3 times resting activity. CONCLUSION: These results add further information to the concept of the interrelatedness of jaw, neck, and trunk muscle activity.

Adult↗

PubMed1987

Reticulo-spinal neurons participating in the control of synergic eye and head movements during orienting in the cat. II. Morphological properties as revealed by intra-axonal injections of horseradish peroxidase.

Previously we described physiological properties of pontine reticulo-spinal neurons which generate bursts and decaying tonic discharges related to eye movements and neck muscle activity during ipsiversive gaze shifts (Grantyn and Berthoz 1987). Two of these "eye-neck reticulo-spinal neurons" (EN-RSN) were labeled by intra-axonal injections of HRP. The present report provides a detailed description of their morphology with an emphasis on the topography of axon collaterals, bouton numbers, and the structure of preterminal ramifications in different target areas. The cell bodies of labeled EN-RSNs were located rostro-ventrally to the abducens nucleus. Their descending axons issued 8 and 13 collaterals (left and right EN-RSN, respectively) at different rostro-caudal levels, between the abducens nucleus and the pyramidal decussation. On the basis of the size of their cell bodies, the isodendritic type of dendritic branching and their multiple collateralization, EN-RSNs correspond to the class of "generalized" reticular neurons, often referred to as The Scheibels' neurons. Collaterals of EN-RSNs terminated in the following structures: the abducens and facial nuclei, the medial and lateral vestibular nuclei, the nn. prepositus and intercalatus, and the bulbar reticular formation. As judged from bouton numbers, the strongest connection of both neurons was with the abducens nuclei. Terminations in the rostral part of the medial vestibular and prepositus nuclei indicate that EN-RSNs may also influence oculomotor output activity through these indirect routes. In the facial nucleus, a majority of terminations was found in its medial subdivision containing motoneurons of ear muscles. However, other subdivisions were also contacted by EN-RSNs. Most terminations in the rostral bulbar reticular formation are distributed to the dorsal, gigantocellular field. Within this field, there is a substantial contribution to the zone characterized by the highest density of reticulo-spinal neurons projecting directly to neck motoneurons. Other target areas which may participate in the modulation of spinal cord activity by EN-RSNs are the ventral reticular nucleus in the caudal medulla and the lateral vestibular nucleus. EN-RSNs also establish connections with precerebellar structures: the prepositus and the paramedian reticular nuclei. The numbers of boutons on collaterals issued within 6 mm of the injection site varied between 37 and 469. The occurrence of presumed axo-somatic contacts was low (0-8.2%) and not characteristic for any particular target area. Local accumulations of boutons in the form of small and large field clusters was a common observation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed2001

Cervical dystonia pathophysiology and treatment options.

Dystonia is a syndrome of sustained involuntary muscle contractions, frequently causing twisting and repetitive movements or abnormal posturing. Cervical dystonia (CD) is a form of dystonia that involves neck muscles. However, CD is not the only cause of neck rotation. Torticollis may be caused by orthopaedic, musculofibrotic, infectious and other neurological conditions that affect the anatomy of the neck, and structural causes. It is estimated that there are between 60,000 and 90,000 patients with CD in the US. The majority of the patients present with a combination of neck rotation (rotatory torticollis or rotatocollis), flexion (anterocollis), extension (retrocollis), head tilt (laterocollis) or a lateral or sagittal shift. Neck posturing may be either tonic, clonic or tremulous, and may result in permanent and fixed contractures. Sensory tricks ('geste antagonistique') often temporarily ameliorate dystonic movements and postures. Commonly used sensory tricks by patients with CD include touching the chin, back of the head or top of the head. Patients with CD are classified according to aetiology into two groups: primary CD (idiopathic--may be genetic or sporadic) or secondary CD (symptomatic). Patients with primary CD have no evidence by history, physical examination or laboratory studies (except primary dystonia gene) of any secondary cause for the dystonic symptoms. CD is a part of either generalised or focal dystonic syndrome which may have a genetic basis, with an identifiable genetic association. Secondary or symptomatic CD may be caused by central or peripheral trauma, exposure to dopamine receptor antagonists (tardive), neurodegenerative disease, and other conditions associated with abnormal functioning of the basal ganglia. In the majority of patients with CD, the aetiology is not identifiable and the disorder is often classified as primary. Unless the aetiological investigation reveals a specific therapeutic intervention, therapy for CD is symptomatic. It includes supportive therapy and counselling, physical therapy, pharmacotherapy, chemodenervation [botulinum toxin (BTX), phenol, alcohol], and central and peripheral surgical therapy. The most widely used and accepted therapy for CD is local intramuscular injections of BTX-type A. Currently, both BTX type A and type B are commercially available, and type F has undergone testing. Pharmacotherapy, including anticholinergics, dopaminergic depleting and blocking agents, and other muscle relaxants can be used alone or in combination with other therapeutic interventions. Surgery is usually reserved for patients with CD in whom other forms of treatment have failed.

Botulinum Toxins↗

PubMed1978

Frequency-response analysis of vestibular-induced neck reflex in cat. I. Characteristics of neural transmission from horizontal semicircular canal to neck motoneurons.

1. Vestibular-induced neck muscle reflexes (vestibulocollic reflexes) were studied with frequency-response methods in unanesthetized, decerebrate cats. The horizontal semicircular canals were stimulated by oscillation of the turntable and EMG activity was recorded from neck extensor muscles. 2. The maximum firing rate of each motor unit was less than 40 spikes/s. The motor units were classified by their maximum firing rates into two groups: HF (high frequency) units which could fire above 20 spikes/s and LF (low frequency) units which could not exceed 20 spikes/s of firing. The HF units had larger gains than the LF units on the average. 3. Compound EMGs, which presumably represent activity of the whole muscle, were examined at different frequencies of stimulation. The gain of compound EMG responses depended on the spontaneous activity. When the spontaneous activity was low or too high, the gain was small. There was an intermediate spontaneous activity level at which the gain became maximal. 4. The phase lag and the gain of the frequency response were represented in a Bode diagram with respect to angular acceleration. The transfer function of the system from the vestibular nuclei to neck EMG activity was estimated by assuming a first-order lag-lead system. A phase lag of 70-80 degrees (0.05 Hz) was found between the averaged activity of vestibular nucleus neurons and cervical motor activity. A positive correlation was observed between the phase lag and the gain of each motor unit. These results cannot be attributed solely to the action of the vestibulospinal tract, but suggest the existence of a neural intergrator in the vestibulocollic reflex arc.

Action Potentials↗

PubMed2000

Muscle forces and spinal loads at C4/5 level during isometric voluntary efforts.

PURPOSE: The goal of this study was to determine neck muscle forces and spinal loads that result from isometric muscle contractions. METHODS: Electromyographic (EMG) activity of the neck musculature and a three-dimensional biomechanical model of the neck were used. The model was EMG-based and estimated muscle forces and spinal loads at the C4/5 level. EMG signals were collected from eight sites at the C4/5 level of the neck using Ag-AgCl surface electrodes from 10 adult male subjects. The subjects performed isometric contractions gradually developing to maximum efforts in flexion, extension, left lateral bending, and right lateral bending. RESULTS: During maximum voluntary contraction (MVC) trials most muscles generated high levels of EMG signal during cervical rotation. The posterior surface of the neck (trapezius) was the only electrode site at which maximum activity EMG consistently occurred by the same method (rotation) in all subjects. Variations in the EMG patterns were observed in different experiments that produced overall neck moments of equal magnitudes. With these data the model computed variations in load distribution among the agonist muscles. Consistent also with EMG distributions, the model also computed co-contractions of antagonist muscles. The average (+/- SD) magnitudes of peak moments were 28.3 (+/- 3.3) Nm in extension, 17.7 (+/- 3.1) Nm in flexion, 16.9 (+/- 2.8) Nm in left lateral bending, and 17.0 (+/- 2.9) Nm in right lateral bending. The model predicted C4/5 joint compressive forces during peak moments were 1372 (+/- 140) N in extension, 1654 (+/- 308) N in flexion, 956 (+/- 169) N in left lateral bending, and 1065 (+/- 207) N in right lateral bending. CONCLUSIONS: Results suggest that higher C4/5 joint loads than previously reported are possible during maximum isometric muscle contractions.

Adult↗

PubMed1993

Use of botulinum toxin in the treatment of cervical dystonia.

Idiopathic cervical dystonia, like other adult-onset focal dystonias, has been notoriously difficult to treat. Multiple approaches, including systemic drug treatment with anticholinergics, antidopaminergics, anticonvulsants, muscle relaxants and many other drugs as well as physiotherapy and psychotherapy, usually lead to only temporary amelioration in a minority of patients. Surgical selective EMG-controlled denervation of dystonic neck muscles produces better and, in the hands of some, lasting improvement. However, the procedure is invasive and as such less well accepted by patients. Local injections of botulinum toxin are strikingly successful in improving postural deviation and pain in about 80% of patients. They can be made on an outpatient basis and appear to be safe even over many repeat sessions. Dysphagia is potentially the most serious side-effect but can be decreased in incidence and severity by injecting lower doses, particularly into the sternomastoid. Major drawbacks at present are a lack of prospective data to establish optimal dosage and volume of injection guidelines to preserve good efficacy at a reduced risk of side-effects, and the need to continue indefinitely with repeat injections approximately every 3 months.

Botulinum Toxins↗

PubMed1985

Patterns of primary afferent termination in the external cuneate nucleus from cervical axial muscles in the cat.

Using the method of transganglionic transport of horseradish peroxidase (HRP), the distribution of primary afferent projections was examined in the external cuneate nucleus (ECN) from different muscle groups in the forequarter of the cat. The terminal zones of afferent fibers from three shoulder muscles--clavotrapezius, acromiotrapezius, and spinotrapezius--were compared to projections from suboccipital muscles, dorsal neck extensors, and muscles of the proximal forelimb. Each muscle group had a labelled terminal zone that occupied a different subvolume of the ECN. The zone labelled from trapezius muscles formed a continuous column in the ECN running from the caudal pole of the nucleus to a level 3.0 mm rostral to the obex. Terminal zones of suboccipital muscles and dorsal neck extensors formed longer columns that extended into the most rostral tip of the ECN, while those of proximal forelimb muscles formed shorter columns confined to the caudal two-thirds of the ECN. At comparable cross-sectional levels in the caudal and middle portions of the ECN, terminal zones from proximal limb muscles were located most dorsomedially, while those from shoulder muscles, dorsal neck muscles, and suboccipital muscles were located in progressively more ventral and lateral regions. The subvolume of the ECN occupied by projections from cervical axial muscles was estimated to be more than 40% of the volume of the nucleus, suggesting that the ECN has a major role in the transmission of sensory information from axial musculature to the cerebellum. Following exposure of all muscle nerves to tracer, a second labelled zone was also identified close to the ECN in the descending vestibular nucleus at transverse levels 2.0-3.0 mm rostral to the obex. Here, reaction product was concentrated around a circumscribed collection of medium-sized, multipolar cells.

Afferent Pathways↗

PubMed1998

Cortico-cortical inhibition of the motor cortical area projecting to sternocleidomastoid muscle in normals and patients with spasmodic torticollis or essential tremor.

OBJECTIVES: To investigate whether the cortico-cortical inhibition originally reported for the human hand motor area is present in the motor cortex for sternocleidomastoid muscle (SCM) and to evaluate the amount of inhibition in spasmodic torticollis and essential tremor. METHODS: Subjects were 14 normal healthy volunteers, 10 patients with spasmodic torticollis and 5 with essential tremor involving neck muscles. A paired-pulse magnetic stimulation was performed for the SCMs and first dorsal interosseous muscles (FDIs). RESULTS: In normal subjects, a subthreshold magnetic conditioning stimulus suppressed responses to a suprathreshold magnetic test stimulus when their interval was 1-5 ms in SCM. This indicates that the similar cortico-cortical inhibitory mechanism is present in the motor cortex for SCM as in the hand motor area. In the patients with spasmodic torticollis, the cortico-cortical inhibitory effect was reduced or absent in SCM, but normal in the FDI. In contrast, in patients with essential tremor, normal cortico-cortical inhibition was seen in both the SCM and FDI. CONCLUSIONS: The cortico-cortical inhibitory mechanisms of the motor cortex for SCM can be studied by a paired-pulse magnetic stimulation method. Our result of reduced cortico-cortical inhibition in torticollis patients suggests abnormal excitability (hyperexcitable or disinhibited) of the motor cortex for SCM in spasmodic torticollis.

Adult↗