Orthotics in Cerebral Palsy

Original Editor - Ghassan Husni Ali and Simon Lalor as part of ICRC Cerebral Palsy Content Development Project

Lead Editors - Kim Jackson, Naomi O'Reilly, Asma Alshehri, Lucinda hampton, Rucha Gadgil, Admin, Simisola Ajeyalemi, Scott Buxton, George Prudden, Amrita Patro, Samuel Winter, Jess Bell, Olajumoke Ogunleye and Carin Hunter

Introduction

Why are the interdisciplinary team members convinced to use the orthoses as part of the treatment plan? Because of the comprehensive understanding of the CP patients, concentrating on the function limitations has a great effect on the new range of improved designs of orthoses to improve the outcome for the benefit of the patient.
In 1994 during the consensus conference held in Duke University, ISPO identifies the goals of the lower limb orthotic management of CP. The identified goals can also be applied in postural impairments of the trunk and upper limbs.
⦁ To correct and/or prevent deformity
⦁ To provide a base of support
⦁ To facilitate training in skills
⦁ To improve the efficiency of gait
It is important that the interdisciplinary team check the patient’s functional limitations according to the GMFCS in order to plan the treatment. The type and design of the orthosis is decided accordingly and can be changed periodically depending on the improvement of the patient condition.

Types of Orthotics

Under the International Standard terminology, orthoses are classified by an acronym describing the anatomical joints which they contain. For example, an ankle foot orthosis ('AFO') is applied to the foot and ankle, a thoracolumbosacral orthosis ('TLSO') affects the thoracic, lumbar and sacral regions of the spine. It is also useful to describe the function of the orthosis.
Types of orthoses which can be used for individuals with Cerebral Palsy are:

Foot Orthoses (FO)

Foot orthotics do not prevent deformity. They provide a better contact of the sole of the foot with the ground.

Supramalleoler orthosis (SMO)

This orthosis extends to just above the malleoli and to the toes. Consider in mild dynamic equinus, varus and valgus instability.

University of California Biomechanics Laboratory Orthosis (UCBL)
The medial side is higher than the lateral, holds the calcaneus more firmly, supports the longitudinal arch. Prescribed for hind and midfoot instability.

Ankle Foot Orthoses (AFO)

The AFO is the basic orthosis in CP and is a crucial piece of equipment for many children with spastic diplegia. The main function of the AFO is to maintain the foot in a plantigrade position. This provides a stable base of support that facilitates the function and also reduces tone in the stance phase of the gait. The AFO supports the foot and prevents drop foot during swing phase. If worn at night, a rigid AFO may prevent contracture. AFOs provide a more energy efficient gait. The brace should be simple, light but strong. It should be easy to use. Most importantly it should provide and increase functional independence.
There are various types of the AFO.

Solid AFO 

The solid or rigid AFO allows no ankle motion, it covers the back of the leg completely and extends from just below the fibular head to metatarsal heads. The solid AFO enables heel strike in the stance phase and toe clearance in the swing phase. It can improve knee stability in ambulatory children. It also provides control of varus/ valgus deformity. Solid AFOs provides ankle stability in the standing frame in non-ambulatory children.

Posterior leaf spring AFO

A PLSO is a rigid AFO trimmed behind the malleoli’s to provide flexibility at the ankle and allows passive ankle dorsiflexion during the stance phase. A PLSO provides smoother knee-ankle motion during walking while preventing excessive ankle dorsiflexion Varus-valgus control is also poor because it is repeatedly deformed during weight bearing. A PLSO is an ideal choice in mild spastic equinus. Do not use it with patients who have crouch gait and pes valgus.

GRAFO or FRO (Ground Reaction or Floor Reaction AFO) 

This AFO is made with a solid ankle, the upper portion wraps around the anterior part of the tibia proximally with a solid front over the tibia. The rigid front provide strong ground reaction support for patients with weak triceps surae. The foot plate extends to the toes. The ankle may be set in slight plantar flexion of (2-3 degrees) if more corrective force at the knee is necessary. Use the GRAFO in patients with quadriceps weakness or crouch gait. It is an excellent brace for patients with weak triceps surae following hamstring lengthening. Children with static or dynamic knee flexion contractures (more than 15 degrees) do not get benefit out of it and do not tolerate the GRAFO.

Anti-recurvatum AFO

This special AFO is molded in slight dorsiflexion or has the heel built up slightly to push the tibia forward to prevent hyperextension during stance phase. Consider prescribing this AFO for the treatment of genu recurvatum in hemiplegic or diplegic children. Anti-recurvatum AFOs may be solid or hinged depending on the child’s tolerance.

Hinged AFO

Hinged AFOs have a mechanical ankle joint usually preventing plantar flexion, but allowing relatively full dorsiflexion during the stance phase of gait. They provide a more normal gait because they permit dorsiflexion in stance phase of the gait, thus making it easier to walk on uneven surfaces and stairs. This is the best AFO for most ambulatory patients. Adjust the plantar flexion stop in (3- 7 degrees) dorsiflexion to control knee hyperextension in stance in children with genu recurvatum. The hinged AFO is contraindicated in children who do not have passive dorsiflexion of the ankle because it may force the midfoot joints into dorsiflexion and cause midfoot break deformity. Knee flexion contractures and triceps weakness are other contraindications where a hinged AFO may increase crouch gait.

The AFO may be fitted with a hinge that allows 10 degrees passive
dorsiflexion while preventing plantar flexion. This creates a more
natural gait

Knee Orthoses

Knee orthoses are used as resting splints in the early postoperative period and during therapeutic ambulation. There are two types of knee orthoses, the knee immobilizer and the plastic knee-ankle foot orthosis (KAFO). The use of such splints protects the knee joint, prevents deformity recurrence after multilevel lengthening and enables a safer start to weight bearing and ambulation after surgery.
Knee immobilizers
Knee immobilizers are made of soft elastic material and hold only the knee joint in extension, leaving the ankle joint free. Consider using them in the early postoperative period after hamstring surgery and rectus tendon transfers.
Consider the knee immobilizer after hamstring surgery.

Plastic KAFOs

Plastic resting KAFOs extend from below the hips to the toes and stabilize the ankle joint as well as the knee. They are more rigid and provide better support to the ankle and the knee in the early postoperative phase. Knee-ankle-foot orthoses with metal uprights and hinged joints (KAFOs) were developed and used extensively in the 1950s and 60s for children with poliomyelitis. Though KAFOs are still used for ambulation in poliomyelitis and myelomeningocele where there is a need to lock the knee joint, they are not useful for the child with CP because they disturb the gait pattern by locking the knee in extension in the swing phase. Donning the KAFO on and off takes a lot of time and they are difficult to wear. For these reasons, KAFOs for functional ambulation have disappeared from use in children with CP. Use anti recurvatum AFOs or GRAFOs for knee problems in ambulatory children.

Use the plastic KAFO at night and in the early postoperative period after
Multi-level surgery to protect the extremity while allowing early mobilization.

Hip Abduction Orthoses

Consider using hip abduction orthoses in children with hip adductor tightness to protect hip range of motion and prevent the development of subluxation. One clear indication for hip abduction orthoses is the early period after adductor lengthening.

Spinal Orthoses

There are various types of braces used for spinal deformity. This braces are not prescribed in order to stop the progression of scoliosis but to provide better sitting balance. As most children with scoliosis need spinal surgery to establish and maintain sitting balance in the long run. A thoraco-lumbo-sacral brace helps the child to sit better during the growth spurt period when spinal deformity becomes apparent, progresses fast and the child out grows custom molded seating devices quickly. Children who are not candidates for surgery for different reasons may use spinal braces instead of seating devices for better sitting.

Upper Extremity Bracing

The indications of bracing in the shoulder and elbow are very limited. An example of a resting splint is a thermoplastic resting wrist and hand splint which keeps the wrist in 10-20 degrees extension, the metacarpal phalangeal joint(MPJ) in 60 degrees flexion and the interphalangeal joint( IPJ) in extension. This type of splint is used at night and during periods of inactivity with the hope of preventing deformity. An example of a functional splint is an opponents splint, which can be used in everyday activities. Hand orthoses may inhibit the active use of the extremity and effect sensation of the hand in a negative way. Use them only in the therapy setting or at school and take them off during other times in the day.

Resting Hand Splint Copy right Smith& Nephew

Functional Hand Splint copy right Smith & Nephew
These are the most known type of orthoses used in one stage of the CP treatment plan, bearing in mind with CP a periodical orthosis assessment has to be done in order to decide if there is a need for changing the design or type.

Orthotic Prescription

Lower Limb Orthoses for Ambulatory Children (GMFCS I, II and III)

Ambulatory children with Cerebral Palsy often present with numerous gait deviations that
primarily result from the loss of selective motor control, decreased muscle strength
and abnormal muscle tone . These motor disorders of Cerebral Palsy are frequently accompanied by disturbances of sensation, perception, cognition, communication, behaviour and epilepsy . Hence, the orthotic management of ambulatory children with Cerebral Palsy requires comprehensive rehabilitation using age-appropriate interventions that encompass the ICF domains of body function and structure, activity and participation, personal and environmental factors . Orthoses are used to manage the secondary musculoskeletal problems of muscle contracture and bony deformity. Without appropriate orthotic intervention, detrimental changes to the gait and function of the child with Cerebral Palsy will occur over less than two years .

A diagnosis of CP does not correlate with any clearly defined rehabilitative intervention strategies, nor does it correlate with a defined set of expected outcomes for the child and family . To provide effective orthotic intervention for children with Cerebral Palsy it is important to clearly identify the functional abilities of each child in order to establish the aims of any orthotic intervention. Through a consensus conference in 1994, the International Society of Prosthetics and Orthotics (ISPO) identified the aims of lower limb orthotic management of cerebral palsy as:

1. To correct and/or prevent deformity.
2. To provide a base of support.
3. To facilitate training in skills.
4. To improve the efficiency of gait 

A literature review conducted by Figuerdo et. al and a report from the ISPO Cerebral Palsy Consensus Conference of 2008 criticised the evidence base relating to the orthotic management of children with Cerebral Palsy. Both documents identified a relatively low amount of research that dealt specifically with the orthotic management of children with Cerebral Palsy.

They also found many of these studies employed poor methodologies causing the evidence to be of a lower scientific quality. Hence, it was recommended in both the literature review and the consensus conference that future studies have more robust methodologies and provide more in-depth descriptions of the participant presentations, the methods used and the orthotic interventions provided  . This will allow the results from future studies to be transferrable to clinical practice.

The incomplete reporting of orthoses in the scientific literature was highlighted as a major area of concern in the literature review and the consensus report. Many studies evaluating the efficacy of orthotic intervention in children with Cerebral Palsy simply described the orthosis being tested as an ‘AFO’. Without sufficient details on the construction material, trim lines used and alignment of the AFOs, it is impossible to replicate the orthosis and allow an orthotist to transfer the orthotic design to their own clinical practice. Ridgewell et al.  produced a systematic literature review to evaluate the level and quality of detail reported about participants, devices and testing protocols to generate best practice guidelines for reporting of orthoses in future studies examining children with Cerebral Palsy. They reiterated that many of the papers failed to provide sufficient information that could allow the synthesis of the information to contribute to the orthotic evidence base.
The body of knowledge on the efficacy of AFOs will gradually grow using well designed studies and provided homogenous patient groups are measured, relevant outcome measures are used and the AFOs evaluated in the study are unambiguously mechanically characterised . Despite some shortcomings in the current literature, there is sufficient evidence available to establish 4 key points on the efficacy of the orthotic management of children with Cerebral Palsy:
1. AFOs provide positive influences on the temporal spatial characteristics, kinematics and kinetics of gait in children with Cerebral Palsy.
2. AFOs can reduce metabolic cost and the energy expenditure of walking.
3. AFOs provide positive effects on ability and function.
4. ‘Tuning’ the AFO and footwear combination (AFO-FC) is critical to optimise the biomechanical benefits of the orthosis and enable positive influences on the knee and hip joints.

Lower Limb Orthoses for Non-Ambulatory Children (Pre-standing and GMFCS IV and V)

Hip Instability (GMFCS IV and V)

Hip subluxation and dislocation due to spasticity is the second most common musculoskeletal deformity seen in children with CP. The GMFCS level of the child is strongly associated with hip displacement, as the lower levels of motor function have increased predictive rates of hip displacement. The overall incidence has been described in the literature at around 35% with variances of around 1% of children with spastic hemiplegia affected up to 75% of children with spastic quadriplegia . Hip displacement that leads to subluxation is associated with greater functional activity limitations, increased pain, development of pelvic obliquity and in turn progressive scoliosis.
There is no evidence that hip abduction orthoses prevent progressive hip displacement over time. A randomized control trial monitored children over one year and compared the use of botulinum toxin type A (BoNT-A) to the adductors and hamstrings and a variable hip abduction orthosis (SWASH) (Figure1) with a control group that received physiotherapy but no orthoses on gross motor function, hip displacement and surgery rates. There were no significant differences between the groups at one year follow up in either the control group or those that received BoNT-A and a hip abduction orthosis. A long term follow-up of three years to this original study found that BoNT-A and hip abduction bracing does not reduce the need for surgery or improve hip development at skeletal maturity .

Figure 1: A Sitting Walking and Standing Hip (SWASH) orthosis that provides variable abduction throughout hip extension and flexion. The hip abduction provided is wide during sitting, but narrow during standing or walking.

http://www.leeprosthetic.com/images/products/po_swash_brace.jpg

While hip abduction orthoses cannot prevent the development and progression of hip displacement and subluxation, they may improve sitting posture, symmetry and comfort in non-ambulant children. Ambulant children may also gain some benefit from hip orthoses that control adduction by decreasing the effects of a scissoring gait, leading to increased standing stability and gait efficiency. There is little evidence to support the widespread provision of a hip abduction orthoses for children with CP. The prescription of hip orthoses for both ambulant and non-ambulant children must be on a case by case basis. The prescription must be intrinsically linked to pre-determined rehabilitation goals and objectively assessed with appropriate outcome measures. If it is found that the hip abduction orthosis is not achieving the rehabilitation goals wear should be stopped.

Ankle Foot Orthoses (GMFCS IV and V)

Children in GMFCS levels IV and V will spend a large amount of their time in seated positions, meaning they are more likely to develop flexion contractures. It has been found that maintaining a spastic muscle in maximum extension for 6-8 hours can help to reduce the development of flexion contractures . AFOs for this group of children are often prescribed to manage the resultant equinus deformity at the foot and ankle with the functional goals of ensuring the child is able to use a standing frame and perform assisted standing transfers if appropriate. However, the gastrocnemius muscle is a bi-articulate muscle, meaning that it crosses both the knee and ankle joints. To provide an appropriate stretch of the gastrocnemius muscle, it is crucial the knee is held in maximum extension with the foot and ankle in maximum dorsiflexion. Therefore, AFOs must be combined with another orthosis such as a stiffened fabric gaiter (Figure 2) or a 3 point knee brace to ensure the gastrocnemius is stretched. AFOs may also be used to manage coronal and transverse plane deformities of the foot in children with GMFCS levels IV and V. Mobile deformities including rear foot varus/valgus and forefoot abduction/adduction and supination/pronation, may be corrected in the casting process and controlled using solid AFOs. Any fixed deformity must be accommodated and maintained in their ‘best’ corrected or most neutral position.

Figure 2:a stiffened fabric wrap around knee gaiter that helps to maintain the knee in extension
http://www.abilitymattersdirect.co.uk/leg-and-arm-gaiters-immobilisers

Spinal Orthoses (GMFCS IV and V)

Children with CP who are more limited in their functional ability are at a greater risk of developing combinations of scoliosis, lordosis and kyphosis. The more severe the deficit, the more likely is spinal deformity to occur, the earlier the age of onset, and curves are likely to be more severe. The progression of the curve becomes more apparent during spinal growth and will continue into adult life. In general, if a child with CP is able to walk, then the chances of developing a severe scoliosis is much less likely compared with wheelchair dependent children. Scoliosis in children with CP has been linked to the effects of gravity when they are placed in a seated position for long periods of time .
The use of spinal orthoses is first line treatment for children with CP who have a related spinal deformity. There is a little evidence to support the use of spinal bracing and provision is on an individual case basis. Any prescription of a spinal orthosis must be combined with the use of seating and sleep systems and also include the use of a standing frame and/or orthoses to help reduce the effects of gravity on the spine and digestive system in the seated position.

Figure 3:A rigid thermoplastic Thoraco Lumbar Sacral Orthosis (TLSO) used to provide 3 dimensional control of scoliosis.
http://www.massgeneral.org/ortho/assets/images/pediatrics/bracing-blue-brace.jpg

Rigid thermoplastic spinal braces (Thoraco Lumbar Spinal Orthoses (Figure 3)) similar to those used to manage idiopathic scoliosis, are often not well tolerated by children with Cerebral Palsy as there has been reports of reduced tolerance due to pressure sores and skin irritation . TLSOs that are made of more flexible material such as polyethelyne, have been found to be better tolerated and provide improved head and trunk control, improved postural position and increased sitting stability  . Although spinal curves appear to progress in most non-ambulant children with Cerebral Palsy, there is a small cohort fitted with a semi-rigid TLSO that experience either slowing of the rate of progression or halting of curve progression. It appears that the more flexible curves respond better to orthotic intervention and this is a good predictor for prescription of a spinal orthosis.

⦁ The HELP Guide to Cerebral Palsy, by: Nadrie Breker, Selim Yalcin. Pages 47-51.
⦁ Orthotic Management of Children with Cerebral Palsy, By: Christopher Morris, MSc, SR Orth. JPO, 2002 Vol. 14, Num. 4, pp.150-158.
⦁ ISPO Report of consensus on lower limb orthotics management of Cerebral Palsy. Nov. 1994, edited by: David N. Condie& Barry Meadows.