Top muscles I. lower limb They are divided into groups based on regional affiliation (topography) and the functions performed by them. Muscles of the upper limb (Fig. No. 87, 88, 89, 90, 91, 92) It is customary to divide on the muscles of the shoulder belt and the muscles of the free upper limb: shoulder, forearm and brushes. Muscles of the lower limb (Fig. No. 85, 86, 93, 94, 95, 96, 97, 98, 99, 100, 101,102,103) - on the muscles of the pelvic belt (pelvis) and the free lower limb: hips, legs and feet. At the same time, between the muscles of the upper limb and the lower, it is impossible to carry out a complete analogy due to the difference in the structure and functions of the belts and the free parts of the limbs. Due to the specifics of the bone function, the shoulder belt are connected to the skeleton of the body moving and have special muscles acting on the collar and especially on the blade. Due to this, the blade and the clavicle have great freedom of movements. On the lower limb, the pelvic belt is firmly, almost motionless, connects to the spine in the sacratling joint.
For better assimilation of a wide variety of extremities muscles, we consider their graultial structure on topography and the function executable (see schema 1).
Muscles of the shoulder belt(Fig. No. 83, 87, 88) are located around the shoulder joint and provide him with a full amount of movements (with the participation of some breast and back muscles). All 6 muscles of this group begin on the bones of the shoulder belt and are attached to the shoulder bone.
1) The deltoid muscle begins from the lateral third of the clavicle, the acromion and the uks of the blades. It is attached to the deltoid pugishness of the shoulder bone. The front of the muscle flexions shoulder, the average - assigns, the rear - extension of the shoulder.
2) The oversight muscle begins on the venge of the spawth of the same name, attached to the large tubercle of the shoulder bone. Takes the shoulder, being a synergist of the middle beams of the deltoid muscle.
3) The sibid muscle begins on the venge of the blade of the same name, attached to the large tuberculk bark. Rotates the shoulder dust.
4) A small round muscle begins from the lateral edge of the blade, attached to a large tuberculus of the shoulder bone. Synergist of the Salt Muscle, i.e. Rotates the shoulder dust.
5) A large round muscle begins from the lateral edge and the lower corner of the blade, attached to the crest of a small tubercle of the shoulder bone. Pulls the shoulder of the book and the Zada, at the same time rotating it inside.
6) The sublock muscle begins from the Snacks of the same name and is attached to the small tubercle of the shoulder bone and its crest. Synergist of a big round muscle and wide back muscles: raised hand lowers, lowered his hand rotates inside.
Deltoid (m. deltoideus) (Fig. 90, 101, 104, 106, 111, 112, 113, 114) takes the shoulder of the duck to the horizontal plane, while the front muscle bundles pull the hand forward, and the rear - back. This is the thick muscle of the triangular shape, covering the shoulder joint and partly the muscles of the shoulder. Its large bundles fanually converge towards the top of the triangle, pointing down. The muscle begins on the axis of the blades, the acromion and the lateral part of the clavicle, and is attached to the deltoid perturbation of the shoulder bone. Under the bottom surface of the muscles there is a fake-shaped bag (bursa subdeltoidea).
Tight muscle (m. Supraspinatus) (Fig. 102, 114) has a triangular shape and lies in a supervolorate of a blade, camping directly under the trapezoid muscle. The oversight muscle raises his shoulder and pulls the shoulder joint capsule, not allowing her pinching. The point of the start of the muscle is on the surface of the tight hole, and the location of the attachment is on the top platform of a large tubercle of the shoulder bone and on rear surface Shoulder joint capsules.
Safety muscle (m. infraspinatus) (Fig. 101, 102, 104, 114) turns the shoulder of the duck, the hand raised turns back and pulls the shoulder joint capsule. This is the flat muscles of the triangular shape that fills the entire sirebo. Its the upper part is covered by the trapezoidal and deltoid muscles, and the lower - wide muscle back and big round muscle. The suitable muscle begins on the wall of the suitable fifth and the rear surface of the blade, and it is attached to the middle platform of a large tubercle of the shoulder bone and the shoulder joint capsule. At the place of its attachment to the shoulder bone there is a docking bag of the siretteel muscle (Bursa Subtendinea MM. Infraspinati).
| Fig. 111. 1 - muscle lifting a blade; 2 — deltoid; 3 - Small diamond muscle; 4 - Malaya breast muscle; 5 - sublock muscle; 6 - a large diamond muscle; 7 - big breast muscle; 8 - front gear muscle; 9 - wide back muscle; 10 - Kryvumoid shoulder muscle; 11 - three-headed shoulder muscles: a) long head, b) medial head; 12 - double-headed arm arm; 13 - shoulder muscle; 14 - Round Pronator; 15 - aponeurosis two-headed arm muscles; 16 - the shoulder muscle; 17 - forearm fascia |
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| Fig. 112. Shoulder muscles and shoulder belts front view 1 - Double-headed shoulder muscle: a) short head, b) long head; 2 - deltoid muscle; 3 - sublock muscle; 4 - Kryvoid-Shoulder Muscle; 5 - Big Round Muscle; 6 - Three-headed shoulder muscle: a) long head, b) medial head; 7 - shoulder muscle; 8 - tendon double-headed arm muscles |
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| Fig. 113. Shoulder muscles and shoulder belts side view 1 - supervoloral fascia; 2 - share fascia; 3 - Big Round Muscle; 4 - deltoid muscle; 5 - Three-chapping shoulder muscle: a) long head, b) side head, c) medial head; 6 - double-headed shoulder muscle; 7 - shoulder muscle; 8 - tendon of the trial muscles of the shoulder; 9 - the shoulder muscle; 10 - long ray wrist extension; 11 - elbow muscle; 12 - forearm fascia |
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| Fig. 114. Muscles shoulder and shoulder belt Rear view 1 - supervoloral fascia; 2 - supervoloral muscle; 3 - share fascia; 4 - Salt muscle; 5 - Small round muscle; 6 - Big Round Muscle; 7 - deltoid muscle; 8 - Three-headed shoulder muscle: a) long head, b) side head, c) medial head; 9 - tendon of the trial muscles of the shoulder; 10 - the shoulder muscle; 11 - long ray sprier of wrist; 12 - elbow muscle; 13 - forearm fascia |
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Small round muscle (m. Teres minor) (Fig. 101, 102, 104, 114) turns the shoulder of the shower, at the same time slightly removing it back, and pulls the shoulder joint capsule. Oblong, rounded muscle form, top part Which is adjacent to the suitable muscle, the front part is covered with a deltoid muscle, and the back part is a large round muscle. The start point is located on the rear surface of the blade below the siretteel muscle, and the place of the attachment is on the lower seat of the large mole of the shoulder bone and the rear surface of the shoulder joint capsule.
Big round muscle (m. Teres Major) (Fig. 101, 104, 105, 112, 113, 114) turns the shoulder inside and pulls it back, leading a hand to the body. The oblong flat muscle adjacent to the widest muscle of the back and partially covered with it in the backyard. In the outdoor department, a large round muscle is covered with a deltoid muscle. The start point is the rear surface of the blade at its lower angle, the place of attachment is the comb of a small tubercle of the shoulder bone. Near the fastening site there is a trunk bag of a large round muscle (Bursa Subtendinea Mm. Teretis Majoris).
Podlopean muscle (m. Subscapularis) (Fig. 105, 111, 112) rotates the shoulder inside and takes part in its delivering to the body. Flat wide muscle of triangular shape, filling the entire subupathy hole. It begins on the surface of the subband pits, and ends on a small tubercle of the shoulder bone and on the front surface of the shoulder joint capsule.
At the fastening site there is a small docking bag of the subband muscle (Bursa Subtendinea Mm. Subscapularis).
a - front view; b, in - rear view;
1 - supervolor muscle; 2-speed muscle; 3 - Small round muscle; 4 - Big Round Muscle; 5 - the long head of the shoulder double muscle; 6 - lateral head of the three-headed muscles of the shoulder; 7 - the medial head of the three-headed muscles of the shoulder; 8 - radial nerve in the playry non-canal; 9 - the sublock muscle; 10 - Kryvumoid-Shoulder Muscle; 11 is a triangular hole; 12 - four-sided hole.
Big round muscle (T. TERES MAJOR)starts from the dorsal surface of the lower corner of the blade; It is attached to the crest of a small tubercal tube.
Function:reducing, the muscle performs in the form of elevation of a rounded form when the enclosed shoulder is given, pulls the shoulder back, participates in bringing, the pronation and extension of the shoulder bone, rotates inside and leads to the body.
Innervation:
Podlopean muscle(t. subscapularis)it is located on the front surface of the blade, filling the subband pamph. Starts from the rib surface of the blade and the subband fascia; It is attached to the small tubercle of the shoulder bone and the articular capsule.
Function: Reducing together with the previous muscles, it produces shoulder lead; Acting insulated, is his Pronator, rotates the shoulder inside, penetrates, leads his shoulder to the body and pulls the capsule.
Since this muscle is multiple, it has a significant lifting force.
Innervation: Podleopartic nerve, C V -C VI.
Muscles that produce movements of the shoulder belt.Schematically movement of the shoulder belt (blades and clavicle) are divided into:
1. Movement forward and backward with the brave of the spawood from the spinal column and bringing it to it.
2. Raising and lowering the blade and clavicle.
3. Movement of the blade around the sagittal axis by the bottom angle in the medial and lateral side.
4. Circular motion The lateral end of the clavicle and at the same time the blade.
Six functional muscle groups participate in these movements.
Movement forward shoulder belt Muscles produce, which crosses the vertical axis of the breast and clearable joint and are located in front of it. These include breast muscles:
1) the big breast, acting on the belt of the upper limb through the shoulder bone;
2) Small breast;
3) Front gear.
Big thoracic muscle (t. Pectoralis Major) It has a significant thickness and width. It covers the top ribs in front and is involved in the formation of the anterior wall of the armpit. And refers to the muscles that go from the body to the free upper limb.
Muscles of the chest and shoulder, carrying out the movement of the shoulder belt.
1 - deltoid muscle; 2 - big breast muscle; 3 - double-headed arm arm; 4 - small breast muscle; 5 - plug-in muscle; 6 - Kryvoid-Shoulder Muscle; 7 - Shoulder muscle.
The big breast muscle pulls forward the blade and removes it from the spinal column. This feature is side.
Basically it participates in the movements of the shoulder bone. If the torso is fixed, then this muscle leads, penetrates and begins the shoulder bone. The lower muscle department can also help rabbing ribs by participating in breathing mechanism.
From the shape of a large breast muscle, the external form of the front surface of the upper body of the body depends largely.
With good development of this muscle and thin skin during the reduction of the muscles, not only its upper and lower boundaries are clearly visible, but also the direction of its separate beams.
Big Big Muscle Building
One of the features of the building of the big breast muscle is that its lower bundles go to the middle and the upper not only from the bottom, but also behind. On the shoulder bone, the lower beams are attached higher than the top moving from the clavicle. Thanks to such a feature of the structure, the upper and lower beams when the shoulder lead is evenly stretched and somewhat unchecked, which is especially well expressed when rising hands up.
Small thoracic muscle Located under the big chest and moves the shoulder belt forward and down, and also participates in the rotation of the blade by the lower angle in the medial side (to the spinal pole). If the shovel is fixed, then this muscle raises the ribs and contributes to the expansion chest When inhaling.
Front gear muscle Located on the lateral surface of the chest and covered with large and small breast muscles. This is the main muscle, moving the blade of the Kepened and laterally. The lower teeth of this muscle lower the shovel and pull its lower corner not only down, but also ahead. In addition, the upper and lower teeth can produce opposite actions, rotating the shovel that the upper, then the lower angle of the shock. The front, the toothed muscle is especially clear when the hand raised. Covering the side surface of the chest, this muscle is the medial wall of the axillary fifth.
Traffic back of the shoulder beltmuscles crossing the vertical axis of the breast and clearable joint and behind it. This muscle group includes:
1) trapezoidal muscle;
2) diamond muscle, big and small;
3) The widest muscles of the back.
Movement up shoulder beltmuscles are carried out that intersect the sagittal axis of the breast-clearable joint and lie with the lateral side of it. They go to the shovel and the clavicle from top to bottom.
Rising shoulder belts are produced by the following muscles:
1) the upper beams of the trapezoidal muscle, which pulls up the lateral end of the clavicle and the acromion of the blade;
2) muscle racoping;
3) diamond muscles, with decomposition of which there is some component, directed upwards;
4) Breast-curable-cottage muscle, which, attaching one of his head to the clavicle, pulls it, and, therefore, the shovel is up.
60. Muscles, discharge and leading shoulder.
Shop shoulder: Deltaid muscle, supervolor muscle.
Deltoid
Tight muscle It begins with a supervoloral fossa of the blade and covering its fascia, and attaching to the large tuberculus of the shoulder bone and partly to the shoulder joint capsule. The muscle feature is to lead the shoulder and pull the articular capsule of the shoulder joint.
Lead shoulder: Big breast muscles, wide back muscle, sublock muscle, suitable muscle.
Big thoracic muscle
Shorty muscle back
Podlopean muscle
Safety muscle
61. Muscles that supine and penetrate shoulder.
Turn the shoulder of the dudder:deltaid muscle (rear bundles), big round muscle, suitable muscle.
Deltoid It starts from the clavicle (the front of the muscle), the acromion (middle part) and the ush of the blades (rear part), and is attached to the deltoid peerness of the shoulder bone. If an alternately works alternately, then its back part, then there is a movement of the upper limb forward and backward, i.e. Flexion and extension. If the muscle is tightened with everything entirely, then its front and rear parts form a relay, on the board of which coincides with the direction of the fibers of the middle part of the muscle, contributing to the shoulder lead to the horizontal level.
Big round muscle It starts from the lower angle of the blade and is attached to the ridge of a small tubercle of the shoulder bone often with one tendon with the widest muscles of the back. Reducing, a large round muscle performs in the form of elevation of a rounded form when the enclosed shoulder is brought. The function of the muscle is to bring, pronation and extension of the shoulder bone.
Safety muscle It starts from the suitable fifth blade. In addition, the site of the beginning of this muscle is the share of fascia. It is attached to the large tubercle of the shoulder bone. The function of the share muscle lies in bringing, supination and extension of the shoulder in shoulder Sustain.
Turn the shoulder inside: Deltaid muscle (front beams), big thoracic muscle, wide back muscle, big round muscle, sublock muscle.
Deltoid
Big thoracic muscle It begins from the medial half of the clavicle (crooking part), the front surface of the sternum and cartilage parts of the upper five or six ribs (sternum-rib), the front wall of the vagina's direct abdominal muscle (abdominal part) and attached to the crest of a large tubercle of the shoulder bone. It belongs to the muscles that go from the body to the free upper limb. This muscle pulls forward the blade and takes it from the spinal column. But this feature is side. Basically it participates in the movements of the shoulder bone. If the torso is fixed, then this muscle leads, penetrates and begins the shoulder bone.
Shorty muscle back It begins on the spawn processes of the lower five-six breast vertebrae, all lumbar, upper sacrats, and from the back of the ileum, four teeth of four lower edges, is attached to the ridge of the small tubercle of the shoulder bone. Leading and penetrating the shoulder bone, it causes lowering the belt of the upper limb and bringing the blades to the spinal pole; The part of the muscle that starts from the ribs can lift them and have some effect on an increase in the amount of the chest when inhaling.
Big round muscle
Podlopean muscle Located on the front surface of the blade, filling the sublocking hole, from which it begins. Muscle is attached to a small tuberculk bone. It makes the shoulder; Acting is isolated, it is his pronator.
Muscles, moving shoulder belt, is a trapezoidal, diamond-shaped, front gentle, raising the blade, small breast.
Trapezoidal muscle (Fig. 34, Table II) Lies the floor of the skin on the back surface of the neck and back. From the back it is visible almost all, in the angle is visible on the side, partly in front - above the clavicle and on the sides of the neck. Together with the deltoid muscle, it forms the shape and silhouette of the upper part of the body - the so-called "shoulders", plastically tying their heads with the neck and with a shoulder belt. Together with his pair in the form, this muscle remotely resembles a trapezoid or a hood back, which was previously called a hooded muscle; separately it looks like an elongated triangle. It starts from the occipital bone, from the spiny processes of cervical and all breast vertebrae. The upper fibers are drawn down, close the rear and side of the rift of the blade, wrapped forward and attached to the upper edge of the outdoor end of the clavicle. The average fibers cover the supervature muscle of the blades and are attached to the upper edge of the bladder asset and to the acromion. From the bottom of the fibers rise in the form of a wedge, throw themselves through the edge of the blades and, bias, partly the stripe muscle, are attached to the inner end of the vanes of the blade. Around the masculous processes of the VI-VII cervical vertebra, the muscle tendon lies in the form of a triangle, which with its pair forms a diamond-shaped depression; In the middle of it protrude these iste processes. The muscle forms tendons at the lower end and next to the bladder rowers; All this often affects the relief of the back.
Act. Attracts the spatula to the spine, while reducing the upper part lifts the shovel and the clavicle together with the raising of the blade, producing "shrug" (see Fig. 3).
Fig. 34. Muscles of the shoulder belt, back, neck and pelvis. BUT - view of the right and rear:
/ - Trapezoid muscle, 2 - VII cervical vertebra 3 - acromion 4 - The vertebral edge of the blade. 5 - Delta muscle. 6 - The angle of the blade (covered with the widest muscle of the back). 7 - the edge of the front toothed muscle covered with the widest muscle. 8 - The widest muscle of the back. 9 - spine. 10- Rear iliac aksu. II - iliac crest. / 2-cresses. 13- average jagged muscle. 14 - Large jagged muscle. 15 - Consipient pocket. 16 - big spit. 17 - Muscle strain of wide fascia. 18 - Outdoor abdominal muscle. 19- rib arc
- 20 - front gear muscle.
- 21 - Rhombid muscle, 22 - Big round muscle. 23 - Small round muscle. 24 - Lucky muscle. 25 - Long head three-headed muscles. 26- The inner head of the three-headed muscles. 27 - the outer head of the three-headed muscle. 28- biceps. 29 - blasting 30 - breast-key
superior muscle;
B. - Right blade with muscles (muscles removed: trapezoid, deltoid and widest back muscle):
/ - Spine. 2 - front gear muscle. 3 - The angle of the blade. 4 - Big round muscle. 5 - vertebral edge of the blade 6 - Small Round Muscle: 7 - Long Muscle, 8 - brachial bone. 9 - acromion. 10 - collarbone. // - Holistic muscle. / 2th blade, 13 - Rhombid muscle. 14 - Muscle raising the blade
Fig. 35 muscle trapezoid and front gear (schemes). BUT - The shoulder is highly up with the rotation of the blade (the widest muscles of the back are removed):
/ - Trapezoidal m. (Upper and lower se parts - both are tense). 2 - Deltaida m. 3 - acromion. 4 - About the blades. 5 - the blade (the lower part of it due to the turn protrudes). 6 -Furning gear muscle is tense. 7 - ribs, 8 - Spine. 9- Border of chest
when exhaling;
B. - The layout of the front gear muscle of the blade and chest (incision): J - sternum. 2 - Rib. 3- Front gear muscle. 4 - Podlopean muscle. 5 - shoulder bone. 6 - Shovel. 7 - diamond muscle. 8 - Spine
The lower cut of the muscle interacts with the raising of the blade while driving up and down. For gymnastic exercises In the hands (for example, on the bars), the lower sections of the trapezoid muscles seem to hang the torso to the blades. This is well noticeable if you observe the model, tightened on the hands between two chairs (actions in which the muscle participates in conjunction with others is described below).
Rhombid muscle (Fig. 34, B). Lies on both sides of the spine, almost all covered trapezoidal. It starts from the spiny processes of the two lower cervical and four-top breast vertebrae, the lacker of the dust and a few books (reminding the form of a rhombus) and is attached to the spawn vertebral edge.
Act. Attracts the spatula to the spine.
Front gear muscle (Fig. 34, 35). Lies on the front, side and rear surface of the ribs. Covered at the top and front of the big thoracic muscle, behind the shovel and the wide muscle of the back (through which the relief of the front gear) is partly visible under the skin in the armpit and below it, alternating with the teeth of the external braid muscle of the abdomen (see Illosh. Laocoon).
It begins 9-10 muscle teeth from 9 upper ribs. The teeth merge into the muscle, which passes between the shovel and edges and is attached to the spinal edge of the blade.
Act. Pulls the shovel forward, produces the introduction described in the introduction (see p. 7, Fig. 2) Hand drawing. At the same time, the working length of the hand becomes larger due to the extension of the shovel, the distance between the spine and the acromion increases, and the distance between the acromion and the yapper remains unchanged. Participates in the complex movements described below.
Fig. 36. Right half of the chest (removed the big breast muscle, the widest muscle of the back and the muscles of the abdomen):
I. - Breast-crooking-cottage muscle. 2 - trapezoidal. 3 - clavicle. 4 - acromion. 5 - Cravoid processed blades, b-small breast muscle. 7 - Deltaid muscle. 8 - Short head double muscle. 9-viscose muscle. 10 - Podlopean muscle. // - Big breast muscle (cropped). 12- Long head double muscle. 13 - The outdoor head of the three-headed muscles, 14 - Front gear muscle. 15 - Shoulder muscle. 16 - Round Pronator. / 7 - tendon double muscle. 18 - radius brush flexor, / 9 - radial brush extensors, 20 - Pirogovskaya fascia 21 - Rib arc. 22 - sternum. 23 - Intercostal muscles. 24 - Japper Vpadina
Muscle - lift the blade (Fig. 34, 42). Lies vertically, partly covered with a trapezoid muscle. It begins from the transverse processes of the four top cervical vertebrae and is attached to the inner corner of the blade.
Act. Pulls the shovel up, interacts with the lower part of the trapezoid muscle.
Small breast muscle (Fig. 36). Lies on the front surface of the chest, covered with a large thoracic muscle.
It starts from II-V ribs in four teeth, goes up and attached to the beak blades of the blade.
Act. Pulls the book and forward with a beak arbitrariness, pressing the top of the blades to the chest and raising its lower angle.
The described five muscles are attached to the blade from different sides and form a powerful muscular apparatus, which is adjacent to the spring stretched between the shovel and the chest. Straightening from different sides, they elastically fix the shovel in relation to the chest, shocking the external pressure and push transmitted through the hand to the shovel during the work of the hand or with shocks (applied by the working hand). The muscles also fix the shovel when the hand needs a solid fixed support, for example, when holding gravity, when the body is harvested on hand. In addition, interacting, they move the blade in any direction; At the same time, some muscles act passively as the clamps, while others pull the shovel (drawing hands, shrug.).
Special attention deserves the movement of the shoulder belt when lifting hands. As already mentioned, lift shoulder in shoulder Sustain stops. As soon as the hand reaches a horizontal level. The further lifting of the hands up occurs due to the rotation of the blade (see Fig. 35, 25). The shoulder is fixed in the shoulder joint, and the shovel turns in the following way. The upper part of the trapezoid muscle, shrinking, pulls against itself the acromion with the outer end of the clavicle, and they rise. The lower part of the trapezoidal muscle is also strained and pulls down the inner end of the blade Axes - it is lowered. At the same time, the lower pendants of the front gear muscle are reduced and the lower angle of the blade is pulled to themselves - it moves forward and up. Consequently, the blade begins to rotate on the surface of the chest so, whose articular area with a fixed shoulder rises up. At the same time, the lower corner of the blade also rises and departs the duck - it can be forgiven, as it acts on the side of the chest, covered with their muscles raised (see Table I).
This movement is clearly visible on the back, especially with embossed muscles: tense and relief of the upper part of the trapezoid muscle, is also tense and embedded its lower plot. The front gear muscle is also tense, and the reliefs and its visible to the skin of the teeth, if you look at the side and in front, as well as its edge, covered with the widest musk of the back. If you become behind the model, this movement on the right blade will occur against the movement of the clockwise, and on the left - on the movement of the clockwise.
Of the described five muscles, only a trapezoid muscle and anterior gear have plasticity. The trapezoid muscle lies entirely under the skin, and all its changes are clearly visible. It is also noticeable to the relief arising from the places corresponding to the transitions of muscle tissue into the tendon: around the VII cervical vertebra, near the blade asset, at the lower end of the muscle.
The front toothed muscle is not visible entirely - under the skin only 4-5 of its lower teeth are lying. But, being a fixer of the blade, the muscle acquires greater power and the appropriate relief in people of physical work and gymnasts, since all the movements of hands associated with great tension are invariably reflected on the shovel and on the locking muscles. Therefore, people with embossed muscles of the front gear muscle will be relief at any movement of the hand associated with a large voltage: lifting gravity over his head, focusing on hand, with hand (for example, cutting, work hammer, etc.). Sleepy people have muscle teeth can even be visible even with ordinary hand movements associated with the blade. In addition, the relief is also the bottom edge of the muscle, Kosos back from the IX rib to the shovel and covered with the widest muscle of the back; With a strong voltage, it acts as a slash roller.