Article - Wheelchair Seating - Policy Article (A52505)

If the prefabricated seat cushion, prefabricated back cushion, or a brand name custom fabricated seat or back cushion has not received a written CVR from the PDAC or if the PDAC has reviewed and determined that the product does not meet the criteria for the code, then it must be billed with code K0669.If a product is billed to Medicare using one of the HCPCS codes that requires written CVR, but the product is not on the PCL for that particular HCPCS code, then the claim line will be denied as incorrect coding.Pediatric size positioning accessories are billed with the codes described in this policy. Codes E1025, E1026, E1027 (lateral thoracic and lateral/anterior supports) are invalid for claim submission.Code E1028 (swingaway or removable mounting hardware upgrade) may be billed in addition to codes E0953, E0955, E0956, E0957. It must not be billed in addition to code E0960. It must not be used for mounting hardware related to a wheelchair seat cushion or back cushion code.Wheelchair seat and back cushion codes are all-inclusive. Use of HCPCS code K0108 or any other HCPCS code to separately bill for added components such as the foam blocks, gel packs, air cells, or equivalent material is incorrect coding.The right (RT) and left (LT) modifiers must be used when applicable. Effective for claims with dates of service (DOS) on or after 3/1/2019, when the same HCPCS code for bilateral items (left and right) is billed on the same DOS, bill each item on two separate claim lines using the RT and LT modifiers and 1 unit of service (UOS) on each claim line. Do not use the RTLT modifier on the same claim line and billed with 2 UOS. Claims billed without modifiers RT and/or LT, or with RTLT on the same claim line and 2 UOS, will be rejected as incorrect coding.TESTING METHODOLOGYThere are two testing methods that may be used to document wheelchair seat cushion criteria: the simulation method and the human subject method. Simulation tests are used to measure loaded contour depth and bottoming out. Human subject tests are used to measure peak interface pressure.Simulation TestSimulation tests measure loaded contour depth and bottoming out. They use standardized models of the human buttocks known as cushion-loading indenters (CLIs). There are two CLIs that are used for simulation testing, a 25 mm CLI and a 40 mm CLI. Specific design features of acceptable CLIs can be found on the PDAC web site.Test method for determining 25 mm and 40 mm of contour depth:Place the test cushion on a flat, horizontal surface. Cushions with curved bases must be stable during contour measurement testing.Align the CLI so that it is centered from the sides of the cushion and so that the ischial tuberosities of the models are 11-15 cm from the rear edge of the cushion. The ischial tuberosity portion of the CLI should be aligned with the analogous portion of the test cushion.Load the CLI to 140 Newtons (31 pounds) & wait 5 minutes.Contact of the lateral buttons with the cushion indicates that the cushion has contoured to 25 or 40 mm depending on the CLI used - i.e., that it has passed the test for that trial.Repeat the test two times waiting 5 minutes between trials.A cushion must pass the respective contour test during all trials to meet the minimum criteria specified in the cushion definition section.Overload test method for measuring bottoming out:Record the height of the CLI from the horizontal surface at the end of the loaded contour depth test described above.Add 47 Newtons (10 pounds) to the CLI and record the height from the horizontal surface after 1 minute.Subtract the height at overload (#2) from the height at standard load (#1).Round the value in #3 to the nearest 5mm.Remove the overload weight and repeat the test twice, waiting 5 minutes between tests and measuring the height in #1 and #2 each time.Determine the median of the three values recorded in #4. This is the "overload deflection".If the overload deflection is greater than or equal to 5mm, then the cushion is determined not to have bottomed out during the test.Simulated use testing:There must be simulation of 12 or 18 months of use of the cushion (depending on the cushion type - see Definitions section). Following simulated use, the measurements for loaded contour depth and overload as described above must be repeated.Test report:There must be a report of the tests which includes:The name and address of the facility performing the tests and the date(s) of the tests; andThe manufacturer and brand name/number of the test cushion; andThe weight of the cushion to the nearest 250 gm; andThe width and length of the cushion; andThe temperature and relative humidity of the room where the tests are conducted; andIdentification of which CLI was used (25 mm or 40mm); andThe results of the three loaded contour depth tests and the overload deflection test prior to simulated used testing; andA description of the method used to simulate cushion use; andA statement specifying the number of months of use that were simulated; andMeasurements as described in #7 obtained after simulated use testing; andA statement attesting that the testing methodology described in this policy was followed; andThe printed name and signature of the person performing or supervising the tests and the signature date.Human Subject TestsThe ability to demonstrate that there is an important reduction in interface pressure in comparison with a standard reference cushion when tested with human subjects is the basis for this approach. Human subject tests must be performed by an entity that has received human subject testing approval from an Institutional Review Board approved by the US Department of Health and Human Services. Ten (10) wheelchair users must be studied, at least five of which must be clinically insensate on the body surface contacting the cushion.Interface pressure measurements are taken with each subject seated on the cushion being tested as well as on a standardized reference cushion (see below). The measurements are obtained with a transducer placed on top of the cushion. Subjects must be seated on the cushion and interface pressure transducer for at least 60 seconds before data is collected. The subject should be positioned in their typical posture as determined by query and independent facility judgment. Three measurements are taken on each subject on each cushion separated by a complete unloading of the cushion for at least 60 seconds.The standard reference cushion must be an uncovered 75 mm ( 5mm) thick high resiliency foam with a rated 25% indentation force deflection (IFD) equal to 45 pounds (density range of 2.6-2.9 pounds/cubic ft and IFD range of 40-49 pounds).There must be a report of the tests which includes:The name and address of the facility performing the tests and the date(s) of the tests; andThe manufacturer and brand name/number of the test cushion; andInformation about the interface pressure measurement device utilized:Manufacturer and brand nameDate of most recent calibrationPercent error of measurement at 50 and 100 mm Hg pressure; andActual 25% IFD and density of the reference cushion (obtained from the foam manufacturer or supplier) and actual thickness of the reference cushion; andInformation on each subject (coding subjects to preserve confidentiality) including:AgeHeightWeightDisabilityButtocks sensation status; andInterface pressure measurements for each subject on the test cushion and on the reference cushion:If the transducer covers the entire seating area, the entire map showing the pressure in each cell must be submitted. The anatomical locations (as determined by palpation) of the right and left ischial tuberosities and the sacrum/coccyx must be identified on each map. (Data can be submitted as a hard copy map or utilizing the device software.) or,If the transducer only covers a portion of the seat surface, measurements must be taken at the following three locations (as determined by palpation): right and left ischial tuberosities and sacrum/coccyx. The report must identify the anatomical location of each set of measurements. The report must list the pressure in each cell at each specified location. The values for the three locations are considered a single test; andThe Peak Pressure Index (PPI) for each subject on the test cushion and on the reference cushion. The PPI is determined as follows:For each test, identify the cell in the sacro-ischial zone with the highest pressure;Determine the greatest sum of pressures in the identified cell and the adjacent cells in a 9-10 square centimeter area. If there are multiple cells with the same "highest pressure", consider all of them in the determination of the "greatest sum". [Note: A 3 cm by 3 cm square or a 3.5 cm diameter circular area are examples of a 9-10 sq cm area. For example, if using an interface pressure sensing array with a cell size of 1 sq cm, 9 cells (a 3 by 3 array) are used and if using a sensing array with a cell size of 2.5 sq cm, 4 cells (a 2 by 2 array) are used.];For each test, calculate the average of the cells with the greatest sum of pressures;Calculate the average of the results obtained in step (c) for the 3 tests on the test cushion and the 3 tests on the reference cushion. These values are the PPIs for the subject on each cushion; andA statement attesting that the testing methodology described in this policy was followed; andThe printed name and signature of the person performing or supervising the tests and the signature date.To determine if the minimum performance characteristics specified in the Definitions section for a particular type of cushion have been met, calculate the average PPI for the 10 subjects on the test cushion and the average PPI for the 10 subjects on the reference cushion. Divide the average PPI on the test cushion by the average PPI on the reference cushion and multiply the value by 100 to give the percentage comparison of Peak Pressure Indexes. If the comparative pressures are less than the specified values (125% or 85% depending on the cushion), then the minimum performance characteristics with respect to pressure have been met.