Sit Skier Fitting
KanSki cages come in fifteen different size combinations. Three heights: short, medium and tall; and five widths: 13” – 17”. When fitting a skier to a cage look at four issues to decide on the proper seat.
(1) What is the competency level of your skier? The higher the cage, the easier it is to edge the ski but the more unstable it becomes. The lower the cage, the more stable it is, but the skier may drag the cage or his/her hip in the water if s/he wants to turn (edge) hard. Start beginning skiers in the shortest cage their height will allow. After they progress, fit them to taller cages.
(2) How tall is your skier? The skier’s height is accommodated by cage height and footplate placement. Ideally, when the skier is in the cage the back of his/her knees or underside of his/her thighs should be slightly weight bearing on the top of the knee bar.
(3) How wide is your skier? There are ways to estimate the correct cage size for your skiers without bringing out a tape measure and physically measuring each student. If they are using a wheelchair, ask what width it is. Check to see if their chair is a good fit (no more than a finger width extra on both sides) and subtract one inch to get the estimated cage size. Another trick is to ask what waist size they wear. A person with a 30” – 34” waist will fit nicely in a 14” cage. These are gross estimations, and only experience with fitting will expedite the sizing process. The only sure way to fit skiers is for them to get into the cage before they get into the water. A proper fitting cage requires that the student slide his/her hips at an angle in order to get past the top rail. The student will need to “wiggle” one hip at a time and not drop straight through. In other words, the top rail is narrower than the users’ hip width. There should be slight contact between the skier’s torso and the top rail.
(4) What cage sizes do you have available? Most programs do not have all fifteen cage sizes, so you will need to use the equipment that is available to you. You can always adapt a cage to the needs of your skier. If the cage is too wide or short, try padding the cage with foam or a rolled up towel and secure with duct tape. For wide cages, pad the top hip rail so there is slight contact with the torso and knees. For short cages, pad the knee bar both under the skier’s knee and at the side of the knees so the legs do not move from side to side. It is very important to avoid the “floppy knee” syndrome in order for your skier to have proper control.
Sling placement is another crucial fitting concern. As mentioned before, the lower the skier is the more stable s/he will feel but the more s/he will drag during a turn. The sling should be as low as possible for the beginning skier and raised as the skier progresses. Extreme caution should be taken to insure that no part of the skier’s posterior comes in contact with the metal supports of the cage! At least two fingers space must be maintained between the skier and the frame. As the sling is raised for an advanced skier, make sure to allow enough slack in the sling for the skier to get his/her hips below the top rail.
Lowering the sling is another way to accommodate a tall skier. Beginning skiers that are long legged will need a taller cage than a skier of equal ability but shorter in height. By lowering the sling, the beginning skier still has the stability offered by the lower center of gravity but will have better contact with the knee bar behind his/her knees.
If is also possible to “level” a person with scoliosis or hemiplegia by raising or lowering one side of the sling. If the skier tends to sit leaning to one side, lower the opposite side of the sling by loosening the sling strap one to two inches. The same applies if the student has a gross strength discrepancy. Lower the sling on the student’s weakest side.
To accommodate small adults or children, it maybe necessary to turn your lowest cage backwards. The cage narrows at the back and by reversing it you get a low super narrow cage. This setup is also used for individuals with fused knees or hip joints, short lower limbs, extreme spasticity, or any disability that will not allow the user to sit with his/her legs over the standard knee bar. Another use for the reversed cage setup is to give back support to someone when a quadback is not available. With the cage in the reverse position the sling should be adjusted so it is almost level with the front bar. CAUTION: in the reverse position the cage tapers radically toward the knees. Be sure the skier is capable of getting out of the cage independently in the event of a fall!
CAGE PLACEMENT ON THE SKI
The fore/aft adjustment of the cage on the ski allows you to balance the skier over the ski. If the skier is moved too far forward or is heavier in the legs than the average size skier, then the ski will “plow” and feel as if it will nose in. Conversely, if the skier is moved too far back, has concentrated weight farther back (i.e., a double leg amputee) or is sitting straight up and back, the ski will porpoise (rock up and down) uncontrollably.
Start with the cage in the middle of the five base holes. This will serve the majority of your average size skiers and become a reference point for any changes. Double leg amputees may need to be moved to the front hole. Students that have difficulty leaning forward or staying forward may also need to utilize one of the two forward mounting holes. Students that have severe leg spasticity that may cause pressure on the tip of the ski may need a cage placement using the back holes.
Skiers come in all sizes and weights. Experimentation with your program’s equipment is the only true cage placement. Watch the attitude of the ski after it planes and modify the cage placement based on how it reacts on the water. The water will break approximately at the skier feet when the ski is properly balanced.
Outriggers are fitted to a ski when extra stability is required. They can be attached to any ski but are usually placed on a wide stable ski (such as the Freedom). The skier you are fitting may have poor balance or coordination, or they may be frightened to the point where a successful “no fall” lesson is mandatory. The outriggers’ supports are sandwiched between the cage and the ski. The amount of stability the outriggers provide are controlled by their degree of angle to the water. Much as training wheels for a bicycle, the outriggers can be set at almost 90 degrees to the skier (parallel to the water) for the most stability or bent up to 45 degrees to offer more control (less stability) for the advancing student.
FIXED HANDLE AND QUADGRIPS
For individuals with poor or no grip an adapted handle or grip should be attached to the ski or cage. For spinal cord related quadriplegics the skier may have a strong elbow flexion which may be useful for holding a set of quadgrips. Experiment with the placement of the grips to utilize the skier’s abilities and to find the most comfortable position.
Sometimes the easiest and best adapted grip device results from securing a ski handle to the starting block. Place the knotted handle in the starting block and wrap the long end of the rope (the end that goes to the towboat) around the tip of the ski, behind the block, and back through the starting block. The knotted handle will be held secure in the block by the pressure from the pull of the towboat. It may be necessary to place a different knot in the rope to accommodate the skier’s need to hold the handle. The skier is able to support him/herself with the chance of it releasing. This extra support can also be useful to assist the skier to lean in the direction s/he wishes to turn.
When a student does not have the cognitive ability to know when it is appropriate to pull the handle out of the starting block, there is a technique for locking the handle in front of the block, under the towrope. Place the knotted bridle through the starting block with the knot behind the block as usual. Take the handle and place it in front of the block under the towline. The pressure from the towboat will keep the handle in place and out of reach of our student. This handle placement will not affect the starting block.
A quadback is attached to a sit ski when there is concern that the skier may lose his/her grip (or do not have a functional grip) and fall back out the rear of the cage. Attach the base supports as directed by the product directions. Be sure to use side straps (suspenders) to support the back. The upright tubing is not strong enough to support the weight of a skier without the suspenders firmly attached to the front of the cage.
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