Gghu

1. PREHENSION

2. • Prehension activities involves grasping or taking hold
of an object between any 2 surfaces of hand. Thumb
paticipate in most but not all the prehension
activities.
Prehensi
on
Power
grip
(full
hand
Precision
handling
(finger thumb
prehension)

3. POWER GRIP PRECISION
Forceful act resulting in flexion of
all finger joints. The thumb acts
as a stabilizer to the object held
in fingers or palm.
Skillful placement of an object
between fingers or between
finger & thumb. No
involvement of palm.
Phases • Opening of hand
• Positioning the fingers
• Bringing the fingers to the
object
• Maintaining the static phase
• Opening of hand
• Positioning the fingers
• Bringing the fingers to the
object
Object is grasped to move
through space by some
proximal joints
Fingers & thumb grasps the
object to manipulate it
within the hand
Thumb is generally adducted. Thumb is generally abducted.

5. POWER GRIP
• Fingers function to clamp on or hold an object into the
palm.
• Fingers sustain flexion position that varies in degree with
size, shape & weight of the object; palmar arches around
it.
• Thumb – serves as additional surface to finger
palm by adducting against the object.
• Different power grips –
• Cylindrical grip
• Spherical grip
• Hook grip
• Lateral prehension

6. • Involves use of all finger
flexors
• FDP works predominantly
• Interossei muscles –
primary MCP flexors,
abductors/adductors
• Thumb usually comes
arround the object
• FPL & thenarmuscles-
flexion & adduction of thumb.
l /
CYLINDRICAL
GRIP

7. • Abductor digiti minimi-Flex and abduct 5th mcp joint
• Opponent digiti minimi and flexor digiti minimi-opposition
and flexion of 5th mcp joint
• Cylindrical grasp is typically performed with the wrist in
neutral flexion/extension and slight ulnar deviation
• Eg:turning a door knob,Holding a glass,etc

8. • Most respect to
cylindrical grip but
greater spread of
fingers to encompass
the object.
• More activity of
interosseus
for e.g. holding a ball.
SPHERICAL
GRIP

9. • Specialised form
of prehension-
function
primarily of
fingers.
• Major activity of
FDP &FDS.
• Load –more distally
FDP, proximally
(FDS)
• Thumb- moderate to
full extension.
• E.g. - carrying a
briefcase.
HOOK GRIP

10. • Contact between
two fingers.
• MCP & IP joint- in
extension as
contigious MCP
joint simultaneously
abduct & adduct
• Extensor
musculature pre
dominates.
• E.g. holding a paper
LATERAL
PREHENSION

11. PRECISION
HANDLING
• Require much finer motor control & more dependent
on intact sensation.
• In “two–jaw chuck”,onejaw is thumb( abducted &
rotated) & 2nd jaw is by distal tip, the pad or the
side of finger.
• 3 varieties of prcesion are –
• Pad to pad prehension
• Tip to tip prehension
• Pad to side prehension.

12. • Involves opposition of pad
or pulp of thumb to pad or
pulp of finger.
• The pad has greatest
concentration of tactile
corpuscles.
• MCP & proximal IP joint
of the finger –partially
flexed
• Distal IP joint- extended or
slightly flexed.
• Thumb- CMC flexion,
abduction & rotation; MCP
& IP joint partially flexed or
extended.
• E.g. holding a foreceps
PAD TO PAD P
REHENSION

13. • Muscle activity
almost same to pad
to pad prehension
with some key
differences like IP
joint of the
fingers & the
thumb have range &
force to create full
flexion.
• MCP joint of
opposing finger
deviates ulnarly.
• E.g. holding a pen.
TIP TO TIP
PREHENSION

14. • Key grip or lateral
pinch.
• Between thumb &
side of index finger
• Thumb-more adducted
& less rotated least
precise form of
precesion handling.
• Eg.holding a key
SIDE TO SIDE
PREHENSION

15. FUNCTIONAL POSITION OF WRIST
& HAND
• The functional position is –
• Wrist complex in slight extension (20°) &
slight ulnar deviation (10°)
• Fingers moderately flexed at MCP joint (45°) &
proximal ip joint (30°) & slightly flexed at distal
IP joint
• It is the position in which all wrist muscles are
under equal tension.