努力學習: 5月 2023

https://www.theottoolbox.com/fine-motor-skills/

In-hand manipulation– In hand manipulation refers to the ability to manipulate objects within the hand. Manipulation of objects within the hand includes three aspects of mobility: translation, shift, and rotation of objects.

Translation is using your fingers to moving a little item from your palm to your finger tips (or your fingertips to squirrel the item into the palm). When you hold a coin in your palm and manipulate it to your finger tips to push it into a piggy bank or vending machine, you are demonstrating palm-to-finger translation.

Shift is moving an object using the pads of your fingers…adjusting the pencil grip is demonstrating finger shift. Another example might be manipulating a button or a zipper with the finger tips.

Rotation is rolling an object using the fingertips. Examples of rotation are rolling a pencil in your fingertips, turning a pencil over to use the eraser, or opening a bottle top by rotating the lid on your finger tips.

Wrist extension– A slightly extended wrist or neutral wrist allows for a functional grasp and optimal position of the fingers in opposition to the thumb. Wrist stability enables the fingers to manipulate objects without the wrist moving around. Proximal stability is needed for distal mobility and this applies in the wrist in relation to the hand and fingers.

Wrist stability

Arch development– Arch support in the hand is related closely to the separation of the sides of the hand. Refinement of fine motor skills in the hand (the radial side) happens when the power half (the ulnar side) is stabilized. A functional fine motor grasp and manipulation of objects is more accurate when the ring and pinky fingers are flexed (bent) into the palm. This positioning stabilizes the MCP arch and allows for control of the pointer and middle fingers. Separation of the two sides of the hand allow for more precise use of the thumb. Hand separation starts when a baby bears weight through their arm and ulnar side of the hand while carrying a toy in the radial side. This simple activity developmentally lengthens the muscles of the ulnar side.

Intrinsic hand strength– The intrinsic muscles are the muscles in the hand that define the arches of the hands, bend the knuckles, and oppose with the thumbs. Among these muscles are a group called the lumbricals. The lumbrical muscles have a job to bend (flex) the MCP joints and extend (straighten) the PIP and DIP joints. When the lumbricals are in action, the hand might look like it is holding a plate with the big knuckles bent and the fingers extended.

Thumb IP joint flexion– The thumb interphalangeal joint is responsible for flexing or bending the end of the thumb. the joint allows us to pick up very small items in pincer grasp and enables a functional tripod grasp while holding a pencil. Sometimes, kids hold their pencil with the thumb IP joint in a hyper-extended position as a result of weakness or lax ligaments and in effort to provide stability while moving the pencil. Other times, kids wrap their thumb over the pencil in a thumb wrap grasp as a result of weakness and also in attempt to provide stability in handwriting.

Thenar eminence strength (thumb side of the hand)– Separation of the sides of the hand divides the hand into halves. The thumb side has a fleshy mass below the base of the thumb called the thenar eminence. These muscles pull the thumb into a bent, flexed position and opposition. positioning stabilizes the MCP arch and allows for control of the pointer and middle fingers.

Hypo thenar eminence strength (pinkie side of the hand)- That same separation of sides divides the pinkie side of the hand. Along the length of the pinkie side is the power muscles which help with stabilization of the hand during precision tasks such as writing with a pencil or cutting with scissors. A cupped palm requires engagement of the hypothenar eminence in order to hold objects in the hand. Hand separation starts when a baby bears weight through their arm and ulnar side of the hand while carrying a toy in the radial side. This simple activity developmentally lengthens the muscles of the ulnar side.

Opposition– Opposition of the thumb means the tip of the thumb touches the tip of a finger, or the fleshy pad of the thumb touches the pad of a finger. When opposing the thumb to the fingers, small objects are able to be held and manipulated. When opposing, the thumb’s thenar muscles work to advancing and positioning objects pencil when writing, managing a button with ease, and pulling a zipper. Rotation of the thumb at the CMC joint is needed in collaboration with flexion of the MCP joint and IP joints. With a closed thumb web space and lateral pinch of the thumb versus true opposition, a child will fumble.

https://www.clinicians-view.com/University/PDF/HF01/HF01TextPreview.pdf