Modifications of a MacLaren Buggy Major for Orthopedic Seat Inserts
EDWARD L. BARBER, B.A.
The MacLaren Buggy Major* has been used for some time at the Rehabilitation Engineering Center of Children's Hospital at Stanford. It offers an attractive, lightweight, folding stroller base to which an individually fitted orthopedic seat insert can be attached ( Figure 1 , Figure 2 , Figure 3 , and Figure 4 ). The main drawback we have encountered is that when the stroller is open for use, its seat is fixed in 90 degrees of hip flexion and the seat back is reclined 60 degrees above the horizontal, thus offering no freedom for variation.
Most of the children seen here need at least two positions of inclination: 1) for maximum hand control, and 2) for resting. Pictured in Figure 3 and Figure 4 is a 12-year-old cerebral palsied boy with tension athetosis. He requires positioning at 90 degrees above the horizontal for hand function and school activities, plus positioning at 70 degrees above the horizontal for dining and resting.
To accomplish this adjustment the MacLaren Buggy is modified by shearing off the aluminum rod cap and removing the U-bracket and aluminum rod from the seat bottom ( Figure 5 ). The removed aluminum rod is then replaced with two pop-rivets so as to reattach the remaining bracket on the seat bottom, as shown in Figure 6 . The seat bottom is now free to be positioned in any degree of hip flexion, or as in this case folded flat against the seat back ( Figure 3 and Figure 4 ), thus allowing for attachment of the seating insert by means of the aluminum bracket shown in Figure 7 .
The seat insert is made of 12.5-mm (1/2-in.) ash plywood. It is padded to meet the individual's therapeutic requirements. A steel rod bolted through the buggy's lower back ( Figure 7 ) serves as the point of articulation. A cold-rolled-steel square tube is used for the upper strut, which fixes the angles of inclination. Pivoted on the insert, the tube is notched where it crosses the aluminum arm of the buggy at the required angles of inclination, and it is held in place by Velcro straps.
The footrest for this application must be adjustable to two positions, to compliment the two-position insert. Like the insert, it is constructed of 12.5-mm ash plywood. It is hung over the lower front aluminum cross member and is removable. The main footrest is fitted with the chair in its upright position. Then, to accommodate the reclined position, a swing-down platform is constructed from a hinged piece of plywood padded with ethylfoam of a thickness to achieve proper foot support ( Figure 3 and Figure 4 ).
To allow the child to participate in floor activities, a floor base is constructed to receive the insert. This base places the child at the proper height for his legs and is constructed strong enough to withstand the child's contractures ( Figure 8 and Figure 9 ).
Most children also require trays. Trays can be attached either directly to the seat insert or to the buggy itself. While no tray has been constructed specifically for the child discussed above, Figures 10 and 11 show examples of trays constructed at this center for other children. The trays can be made of ash plywood and coated with sealer, or they can he made of Lexan polycarbonate plastic. The latter, although more expensive, is preferred for durability, cleanliness, and transparency, which allows the child to look through the tray and therefore avoids blocking part of his world from view.
In all of the modifications made to the MacLaren Buggy and in the devices which we attach to it, the original themes must remain. The buggy and orthopedic MacLaren Buggy Major seat insert system must be attractive, as lightweight as practical, and must still allow the buggy to fold flat**.
- When fastening the wood parts together, use screws and a white wood glue (i.e., "Elmer's Glue-All").
- When fabricating the metal parts, break all sharp edges and then file smooth.
- To finish, an exterior stain was used (i.e., Olympic Ash).
- While the maximum interior (uprights) dimension is supplied, all others are dependent upon the patient and his/her orthopedic requirement.
- The upholstery was put on after all modifications to foam were made. A number of fittings were needed over a period of one month to adjust the insert to the patient.
- The illustrated footrest worked quite well for this patient, but each footrest should be constructed uniquely for the specific needs of the patient concerned.
Figures 10 and 11 were furnished by Ann Yamane, Mobility Assistant, Children's Hospital at Stanford.
* MacLaren Buggy Major made by Andrew MacLaren, Ltd., Barby nr. Rugby, England. Imported into the United States and distributed by MED-Medical and Hospital Equipment, 1215 S. Harlem, Forest Park, IL 60130; and Robin Aids, 3353 Broadway, Vallejo, CA 94590.
** Inquiries regarding details of the recommended modifications should be referred to the author at 710 North Lake Shore Dr., Chicago, IL 60611.