Use of a Multiply Adjustable Hip-Control Orthosis in Cerebral Palsy *
BY Y. CHALLENOR, M.D.**
During the last 10 years we have found a significant role for a hip-control orthosis which combines the following features:
- Adjustable adduction with unlimited abduction
- Adjustable limitation to internal rotation with free external rotation
- Free flexion and extension for ambulation or sitting, with a lock available for night positioning at zero-degree extension
- Asymmetric adjustability of the above features for the child with asymmet-
- ric spasticity.
For mild to moderate spasticity the orthosis is best used as an ambulatory alignment control and to supplement physical therapy. For severe spasticity its more favored use is for sitting alignment control, or as a night-positioning orthosis.
A frequent need in aligning the lower extremities of the ambulatory child with cerebral palsy is a combination of control for hip adduction and internal rotation caused by spasticity. The adduction tends to produce a valgus alignment at the knee and to potentiate pronation at the subtalar joint. On many occasions, correction of hip alignment produces significant control of these secondary deformities at the knee and subtalar joints. The goals of an orthotist approaching this problem would be to limit hip adduction and internal rotation while providing minimal limitation of other planes of motion at the hip, and to do so without stimulating further adductor spasticity (Figure 1) .
In 1966 Garrett described a hip-control orthosis which controlled adduction while allowing free abduction 1 . In 1975 several modifications of this hip-control orthosis were described, including I) a screw to adjust abduction, 2) medial condylar extension with the aim of contributing to internal rotation control, and 3) a plunger lock at hip level to allow locking the hip at full extension for standing or sleeping 2 .
Since 1973 we have used a multiply adjustable hip-control orthosis combining the features noted above as well as a more active control of internal rotation 3 . We find that the medial condylar extensions alone do not control internal rotation, although they have the alternate benefit of distributing the pressures needed to control adduction over as wide an area as possible. This wide distribution of pressure prevents stimulation of more adduction spasticity, which can sometimes occur with narrow thigh bands. The additional control of internal rotation is adjustable by a set screw (Figure 2) . Other design variations can include an adjustable pelvic band or a plastic molded pelvic band for more accurate alignment control (Figure 3) . The individual adjustments on each side are easily adaptable for the needs of a child with asymmetric spasticity.
This device is applicable to children with some standing balance and control of weight shifting and reciprocation, with mild-to-moderate hip adductor and/or internal rotator spasticity, particularly if the problem is accentuated by fatigue during the course of the day. It is also applicable to the child whose quality of gait improves with modest manual control from a therapist, but who loses this degree of control without manual facilitation. While the device is primarily used for hip control during ambulation, it can readily be adjusted into greater degrees of abduction for control of hip adductor spasticity during sitting or during sleep. The device is less effective for children with severe spasticity in the standing position, but it can be used with severe spasticity in sitting or lying positions. It is our observation that the type of hip internal rotation which is sharply limited to the toe-off portion of gait (often associated with a burst of medial hamstring activity on EMG kinesiologic studies) is also less well controlled.
In many cases the adequate control of hip alignment decreases valgus stress at the knee and markedly reduces the tendency to pronation at the subtalar joint (Figure 4) . However, if these secondary problems are not fully corrected, use of an appropriately supportive shoe and/or foot-ankle orthosis may be considered. It should be emphasized that the orthosis is an alignment-control device which has an important role in supplementing therapy. However, while the orthosis can control adductor and internal rotation spasticity, it cannot change weight-shifting ability nor the ability to dissociate flexion and extension for reciprocation. Thus, these particular components of gait would need physical therapy rather than orthotic attention. The orthosis also has a role in gait retraining after surgery as well as in maintaining surgical results by its use as a night-positioning orthosis. On rare occasions, we have had children who had excessive abduction after obdurator neurectomy and adductor tenotomy. In these few children the orthosis was used without the set screw adjustable features in order to control mediolateral alignment without impeding flexion and extension (Figure 3) . We have found it advantageous to keep on hand many stock orthoses which are adjustable for length and pelvic-band girth for short-term use, or for evaluation of orthotic effect prior to prescription3.
The basic orthotic components are available from: Hosmer Dorrance Corporation P.O. Box 37 Campbell, CA 95008. These components include the adjustable adduction-stop feature and the cam lock. However, at the time the orthotist attaches the joints to the pelvic band, the external rotation hinge and screw for adjustment must be added.
- Garrett, A. L., M. Lister, and J. Bresnan, New concepts in bracing for cerebral palsy. Phys Ther, 46:7:728-733, July 1966.
- Messinger, A. L., and C. W. Haviland, A new hip-action adjustable abduction orthosis. Inter-Clin Inform Bull, 14:1:1-4, 1975.
- Challenor, Y. B., Orthoses for children, chap. 18 in: The Child with Disabling Illness. W. B. Saunders Pub., Philadelphia, 1974.
*Text of a paper presented at the American Academy of Cerebral Palsy and Developmental Medicine annual meeting in Boston, Massachusetts, October 1980
** Director, Department of Rehabilitation Medicine, and Associate Clinical Professor of Rehabilitation Medicine, Columbia College of Physicians & Surgeons, New York, New York