chap 13

pinch grip

(type of pad to pad grip) * involves thumb & one finger (usually index finger) *holding a coin

three-jaw chuck

(type of pad to pad grip) *involves thumb & 2 fingers (usually index & middle fingers) *most common of all precision grips *holding a pen or pencil

lumbrical grip (AKA: plate grip)

*MCP flexed & PIP &DIP joints extended, thumb opposes the fingers holding an object horizontal *AFLACK *used when need to keep something horizontal(plate or tray)

cylindrical grip

*has all fingers flexed around the object, thumb is wrapped around object in opposite direction often overlapping the fingers. ex) hammer, racquet,wheelbarrow handle,flashlight *(variation) 5th finger joints flexed most, 2nd finger joint only partly flexed.thumb lies // & against the handle, wrists in slight ulnar deviation. This grip allows a forceful but more control of tool. ex) golf club, screwdriver

pad to side grip (AKA: lateral prehension)

*has the pad of the extended thumb pressing an object against the radial side of index finger *strong grip but allows less fine movements *UE prostheses adapts this type of grip *a person who has lost opposition but has retained thumb adduction can grasp & hold small objects (like a key)

side to side grip

*requires adduction of 2 fingers (usually index & middle) *weak grip, doesn't permit much precision * holding a cigarette, pen (not writing) *thumb is not involved

pad to pad grip

bringing pads of fingers & thumb together

3 common power grips

cylindrical, spherical, hook

primary function for the hand

grasp or prehension: means the hand id designed to hold or manipulate objects

spherical grip

has all fingers & thumb abducted around an object, fingers are spread apart, palm of hand not involved * holding apple or a doorknob, picking up a glass by its top

hook grip

involves 2nd through 5th fingers flexed around an object in a hooklike manner. mcp joints are extended & PIP & DIP joints are in some degree of flexion * thumb not involved so person can only do hook grip if lost thumb (med nerve) *holding on to handle like a suitcase, wagon, bucket

tip to tip grip ( AKA: pincer grip)

involves bringing the tip of the thumb up against the tip of another digit usually the index finger, to pick up a small object such as a pin (sewing) or coin (flat side)

2 types of prehension

power grips and precision grip

power grip

used when an object must be held FORCEFULLY while being moved about by a proximal joint muscles (holding a hammer or doorway) *often a power grip involves an isometric contraction w/no movement occurring between the hand &object being held

precision grip (aka: precision prehension)

used when an object must be manipulated in a finer type movement such as holding a pen or threading a needle *tend to hold hold the object btw the tips of fingers & thumb