CASE REPORT FORUM--Observations of Ice-Skating
Prostheses Developed for a
1-Year-Old Transtibial
Amputee
Carole St-Jean, CP(c)
Celine Goyette
ABSTRACT
The purpose of this article is to share the authors' experiences
fitting a very young figure skater who has bilateral transtibial
amputations with different components during her first seasons of skating as an amputee. Her first ice-skating prostheses incorporated modified articulated feet for children, allowing plantarfiexion with some additional dorsiflexion at the
ankle. However more movements and push-off were needed
to accommodate jumping and more difficult ice figures.
A Dual-Ankle Spring, Multi-Axial Rotation System
(D.A.S.-M.A.R.S.) unit with a Seattle Light Foot was then fitted on each prosthesis to provide torsion motion as well as
eversion, inversion, plantar- and dorsiflexion. As a result, the
subject's ice-skating abilities improved, and more precise
movements, jumps and turns were accomplished. Subjectively, these improvements were greatly appreciated by the
young skater
Introduction
During the cold winters in Canada, ice skating is a popular
sport among children; they enjoy playing hockey and figure
skating as well as recreational skating. Consequently, some
children who have amputations make it a personal goal to
learn to skate. Skating prostheses, in comparison to walking
prostheses, need special alignment. Also, they generally are
fitted with components that offer multiaxial movements at
the ankle such as the multiaxial foot (e.g., Gressinger foot)
and the Multiflex Endolite ankle. Because of their sizes
and weights, these components usually are intended for
adult prostheses.
In 1991, a 6-year-old female patient (hereinafter referred
to as M.-C.C.) lost both legs at the transtibial level and
parts of six fingers at the transphalangeal level as the result
of a meningococcus virus infection. One year after amputation, she asked the authors to fabricate ice-skating prostheses to allow her to ice-skate again. At the time, she was not
a full-time walker with her prostheses; she alternated between using her prostheses, using a wheelchair and walking
on bent knees (well-protected with volleyball pads).
The authors' first goal was to fabricate a pair of skating
prostheses that would offer M.-C.C. additional movements
at the ankle level yet provide good stability. Small prosthetic components were required to fit the 7-year-old patient. As the figure-skating skills of the patient improved, a
second pair of prostheses was fabricated with more flexible
components to increase movement at the ankle.
Method
First Pair of Skating Prostheses
The first pair of ice-skating prostheses incorporated articulated feet for children (model 1H19, size 18 cm). A posterior bumper #2F3 in the heel of the 1H19 foot allowed 27
degrees of plantarfiexion at the ankle. The articulated foot
was modified with an additional smaller bumper #2F3 in
the anterior part of the keel of the ankle and foot (see Figure 1
). This bumper allowed 14 degrees of dorsiflexion
movement.
Supracondylar sockets (laminated with orthocryl lamination resin #617H19) were then specially aligned on the
modified articulated feet. Looking in the sagittal plane, the
center of the anteroposterior measure of the socket fell in
front of the ball of the prosthetic foot. This anterior linear
displacement of the socket helped the patient maintain balance (1), turn and push off for acceleration and jumps. The
normal 5 degrees of knee flexion were provided in the
sockets. PELITE liners (3/16-inch) also were used to facilitate donning and increase comfort. Durasleeved neoprene
sleeves were used to maximize suspension.
Good dynamic alignment was important at this stage to
allow the blades of the skates to remain in proper contact
with the ice. The feet were set with neutral rotation to keep
the skates parallel during skating.
The first pair of skates used by M.-C.C. were made of
molded plastic. They provided the lateral stability necessary in the beginning stages of skating with bilateral
transtibial amputations. In addition, the blades of the skates
were modified by eliminating the first two ticks of the
blades to help prevent stumbling on the ice.
The lengths of the skating prostheses were shortened so
M.-C.C. would be the same height with her skates as with
her walking prostheses. This modification provided the patient with more stability.
Second Pair of Skating Prostheses
The second pair of transtibial skating prostheses was fabricated after a full season of skating. M.-C.C. was then 8 years
old and had improved her skating skills. Her skating instructor had asked if additional movements at the ankle
level could be provided to facilitate sharp turns and add
push-off for jumping.
By this time, M.-C.C. had become a full-time prosthetic
user. Her walking prostheses consisted of supracondylar
suspension transtibial sockets, 3/16-inch PELITE liners and
Seattle light feet for children (SLF-32). The small size of
the prosthetic feet (19 cm) limited the choice of more flexible ankle components for her new skating prostheses. The
Seattle feet were kept since they allowed adequate toe action and push-off. To the authors' knowledge, the only
"multiaxial" ankle units available in children's sizes (19 cm)
were the Dual-Ankle Spring Multi-Axial Rotation System
units. The D.A.S.-M.A.R.S. unit chosen for M.-C.C. (see
Figure 2
) provided 10 degrees of plantarfiexion, 5 degrees
of dorsiflexion and 7 degrees of torsion (rotation) in both
directions as well as eversion and inversion movements at
the ankle.
Static alignment for the second pair was similar to that of
the first pair. Because of torsion, eversion and inversion at
the ankle, dynamic alignment was critical to keep the
blades flat on the ice. Durasleeve neoprene sleeves again
were used to provide additional suspension. The new prostheses were 21/2 cm taller than the first pair to accommodate normal growth during the past year.
Softer leather skates were fitted with the new prostheses
for additional flexibility (see Figure 3
). The blades were not
modified since all blade ticks were needed for acceleration
and turns. The cosmetic appearance of the D.A.S.-M.A.R.S.
unit was not a problem since the ankle unit was hidden
within the skate.
The prostheses were tested in the prosthetic laboratory
while walking between parallel bars and then on ice.
Discussion
The first pair of skating prostheses fitted for M.-C.C. with
the modified articulated feet provided more plantarfiexion
and dorsiflexion movements at the ankle level than did the
second pair with the D.A.S.-M.A.R.S. units. The lateral stability of the first pair was good since the only movements
allowed were in the anteroposterior plane. This permitted
an easy forward propulsion from one skate to the other and
proper balance on the skates; it facilitated the process of
learning to skate with prostheses after amputations.
The second pair of skating prostheses fitted for M.-C.C.
with the D.A.S.-M.A.R.S. units provided less plantar- and
dorsiflexion movements at the ankle than the modified articulated feet. However, it allowed torsion, inversion and
eversion movements at the ankle (2). With these additional
movements, M.-C.C. accomplished more advanced ice-skating movements: forward and backward crosscuts, waltz
jumps (half revolutions), mohawk movements and spirals.
With improved skating skills, M.-C.C. could effectively
use lateral and torsion movements of the D.A.S.-M.A.R.S.
units during skating. Such ankle movements with her first
skating prostheses would have created instability and hampered the process of learning to skate with prostheses.
The D.A.S.-M.A.R.S. units with the Seattle Light Foot 32
were 150 g lighter than the modified articulated foot 1H19
with the wooden ankle. This difference in weight was slightly noticeable to M.-C.C. The limitations in movement
caused by the molded plastic skates versus those caused by
the leather ones were not assessed.
The young skater greatly preferred the second pair of
skating prostheses with the D.A.S.-M.A.R.S. units. Since using these prostheses, she has completed four figure-skating
levels in her skating club.
Conclusion
Lateral stability appears to be important when fitting skating prostheses to bilateral amputees learning to skate with
prostheses. By using modified articulated feet as previously described, additional dorsiflexion movements at the ankle seem to facilitate elementary skating.
As skating skills improve, prosthetic components that offer additional lateral and torsion movements may facilitate
more advanced skating. In this case, the D.A.S.-M.A.R.S.
units were sufficient since they were durable and offered adequate movements for ice skating. The same technical and
clinical choices could be applied for roller-skating or in-line
skating.
Being able to skate motivated M.-C.C. to use her walking
prostheses full-time. It also allowed her to participate in
skating activities enjoyed by other children. As a result of
the modifications described, the patient gained renewed
feelings of satisfaction and success.
Acknowledgments
The authors wish to thank The War Amputees of Canada for providing funding for the skating prostheses and M. Jerome Voisin
(Acadian Prosthetic and Orthotic Aids Inc.) for his technical advice about the D.A.S.-M.A.R.S. units.
CAROLE ST-JEAN, CP(c), is a Canadian-certified prosthetist at
the prosthetic department for children at Marie-Enfant Hospital,
5200 Belanger est, Montreal Quebec Canada, and at the Montreal Rehabilitation Institute, 6300 Darlington, Montreal, Quebec,
Canada.
CéLINE GOYETTE is a prosthetist-orthotist at the prosthetic
department for children at Marie-Enfant Hospital.
References:
- Kegel B. Physical fitness. Sports and recreation for those
with lower-limb amputation or impairment. J Rehab, Res and
Devel Service, Clin Supp 1985; 1.
- Voisin P. Dual-Ankle Springs (D.A.S.) foot-ankle system.
Orth and Pros Spring 1987; 41:1:27-31.
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