Although gait and posture vary among children with cerebral palsy (CP), certain patterns can be identified and classified by clinicians using various assessment tools. In general, spastic motor patterns remain relatively consistent from day to day, but they may change over time due to aging and therapeutic interventions.1
One of the most common changes with age is the transition from toe walking, which occurs due to overactivity of the gastrocnemius muscle, to a crouch gait pattern, characterized by increased hip and knee flexion and ankle dorsiflexion.2 This transition is commonly observed in children with spastic diplegia or spastic quadriplegia, but it may be accelerated by an uncontrolled lengthening of the heel cord.3,4
There are differences that can be observed in gait patterns between CP subtypes. In spastic hemiplegia, the involvement is more pronounced in the lower limb, often leading to true equinus gait (toe walking). In contrast, spastic diplegia and quadriplegia tend to involve proximal muscles more severely, resulting in patterns such as apparent equinus gait or crouch gait.5
It is essential to distinguish between gait patterns and postural patterns, as postural abnormalities are typically more visible during the mid- and late-stance phases of walking.
The most widely accepted classification of gait patterns in spastic hemiplegia is the one proposed by Winters et al.5 This classification is based on sagittal plane kinematics and divides spastic hemiplegia into four primary gait patterns.
In type 1 hemiplegia, there is a foot drop that is noted most clearly in the swing phase of gait due to inability to selectively control the ankle dorsiflexors during this part of the gait cycle. There is no calf contracture and therefore during stance phase, ankle dorsiflexion is relatively normal. This gait pattern is uncommon and is typically observed following prior calf lengthening procedures, as described by Winters et al.5 The only management required is a leaf spring AFO. Spasticity management and contracture surgery are not required.
Type 2 hemiplegia is the most frequently observed form in clinical settings and is marked by true equinus caused by spasticity or contracture of the gastrocnemius-soleus complex. This results in persistent ankle plantarflexion during stance and often coexists with foot drop during swing due to weakness in the dorsiflexors. The two subtypes are:
2a: Equinus with a neutral knee and extended hip
2b: Equinus with knee hyperextension (recurvatum) and extended hip
The excessive activity of the plantarflexion-knee extension mechanism may lead to full knee extension or recurvatum.6 Management commonly involves botulinum toxin type A (BTX-A) injections, which are especially effective in young children, and supplemental casting when mild contractures are present.
Orthotic support is essential to address foot drop and enhance the outcomes of BTX-A. In the presence of knee recurvatum, a hinged AFO with a plantarflexion stop or leaf spring AFO is preferred. Surgical intervention, such as tendo Achillis or gastrocnemius lengthening, is reserved for severe fixed contractures. Equinovalgus deformities can be managed initially by calf injection and an AFO. Calf injection often improves AFO tolerance and efficacy type.
Type 3 hemiplegia is defined by gastroc-soleus spasticity or contracture, limited ankle dorsiflexion during swing, and a flexed, stiff-knee gait due to combined hamstring and quadriceps overactivity. Management includes BTX-A injections for the gastroc-soleus and hamstrings to reduce spasticity, followed by surgical lengthening if contractures develop. The most effective long-term treatment for stiff knee is medial hamstring lengthening combined with rectus femoris transfer to the semitendinosus.7,8
Type 4 hemiplegia presents with significant proximal involvement, resembling the gait seen in spastic diplegia, but with pronounced asymmetry due to its unilateral nature, often including pelvic retraction. In the sagittal plane, the child exhibits equinus, stiff-knee flexion, hip flexion, and anterior pelvic tilt. In the coronal plane, there is hip adduction, and in the transverse plane, notable internal rotation. Management strategies for distal issues are similar to those used in type 2 and type 3 hemiplegia. However, due to the high incidence of hip subluxation, thorough radiographic hip assessment is essential.9 Effective treatment typically involves adductor muscle lengthening and femoral external rotation osteotomy to address hip alignment. Failure to correct hip adduction and internal rotation often leads to failure of distal interventions and poor functional outcomes.
The patterns of knee involvement in spastic diplegia described by Sutherland and Davids are an excellent basis for classifying postural and gait patterns in spastic diplegia, with modifications to better reflect clinical observations.10 This classification considers the entire sagittal plane, including the pelvis, hip, knee, and ankle, rather than isolating individual joints. It also integrates the concept that a stiff-knee pattern may appear within other gait types, rather than being a distinct category on its own. The classification is organized from early patterns dominated by calf spasticity (equinus) to more advanced or progressive patterns involving hip flexors and hamstrings (crouch gait), reflecting typical changes seen with growth or after interventions.
A key factor in understanding these gait deviations is the presence of torsional deformities and foot abnormalities, often linked with muscle-tendon contractures. These issues are collectively referred to as lever arm disease.1 Muscles function most efficiently when acting on straight, properly aligned bones. When there is medial femoral torsion, lateral tibial torsion, or foot deformities like valgus and abduction, the mechanical advantage of muscles is reduced, leading to inefficient gait and compensatory movement patterns.
An essential biomechanical principle discussed is the plantarflexion-knee extension couple, which explains how foot position influences knee motion during stance. A stable foot aligned with the direction of walking allows the gastroc-soleus complex to effectively control forward progression of the tibia. This alignment creates a ground reaction force anterior to the knee, which helps extend the knee and reduces reliance on the quadriceps.
Conversely, weakness or over-lengthening of the gastroc-soleus muscles, combined with a malpositioned or deformed foot, can lead to crouch gait. Correcting foot alignment, addressing tibial torsion, and using ground reaction AFOs can help restore the integrity of the plantarflexion-knee extension couple and improve gait mechanics.
When the younger child with diplegia begins to walk with or without assistance, calf spasticity is frequently dominant, resulting in a true equinus gait with the ankle in plantarflexion throughout stance and the hips and knees extended. True equinus may be hidden by the development of recurvatum at the knee. The patient can stand with the foot and the knee in recurvatum.11 The equinus is real but hidden. BTX-A can be very effective for gastrocnemius spasticity to improve stability in stance. A more stable base of support can be enhanced using hinged AFOs. A few children with diplegia remain with a true equinus pattern throughout childhood and, if they develop flexed contracture, may eventually benefit from isolated gastrocnemius lengthening.12 The persistence of this pattern is unusual and seen in only a small minority of children with diplegia. It is more common in children with spasticity, secondary to spinal lesions (e.g., hereditary spastic paraparesis).
The jump gait pattern is commonly observed in children with spastic diplegia and involves proximal muscle involvement, including spasticity of the hamstrings and hip flexors in addition to calf muscles. In this gait pattern, the ankle typically presents in equinus, while the knee and hip remain in flexion throughout stance and swing phases. An associated stiff-knee component is frequently present due to excessive rectus femoris activity during swing, which limits knee flexion and contributes to inefficient gait mechanics.
This description aligns with the classification proposed by Sutherland and Davids, who emphasize the presence of a stiff knee in jump gait.10 Conversely, Miller et al. describe a variant where the ankle appears neutral rather than in equinus.11
As the child grows older and gains weight, several biomechanical changes can occur that reduce the effectiveness of the plantarflexion-knee extension couple, leading to a shift in gait patterns.2,10,13 Equinus may gradually decrease as hip and knee flexion increase, often resulting in a phase known as apparent equinus, where the child appears to be walking on their toes.6,11 However, observational gait analysis may mistakenly interpret this as true equinus, whereas sagittal plane kinematics reveal that the ankle has a normal range of dorsiflexion but excessive flexion at the hip and knee throughout the stance phase.
At this stage, weakening the gastrocnemius through BTX-A injections or surgical lengthening can be counterproductive, as it may lead to crouch gait and impair overall function. Instead, management should prioritize addressing proximal muscle involvement, particularly the hamstrings and iliopsoas, which may benefit from spasticity treatment or musculotendinous lengthening.14
Crouch gait is characterized by excessive dorsiflexion or calcaneus positioning at the ankle, combined with excessive flexion at the knee and hip. It is commonly observed in children with more severe cases of spastic diplegia and is the predominant gait pattern in those with spastic quadriplegia. Unfortunately, the most frequent cause of crouch gait in children with spastic diplegia is progressive crouch gait, which is challenging to manage. Treatment typically involves lengthening of the hamstrings and iliopsoas, the use of a ground reaction AFO, and correction of associated bony deformities such as medial femoral torsion, lateral tibial torsion, and foot stabilization. In younger children, isolated heel cord lengthening can sometimes be performed; however, if spasticity or contractures of the hamstrings and iliopsoas are not identified and properly managed, this procedure may lead to a rapid increase in hip and knee flexion, exacerbating the crouch gait pattern.11 This results in an inefficient, high-energy gait that often leads to anterior knee pain and patellar pathology during adolescence. Frequent BTX-A injections targeting the gastroc-soleus complex, without addressing hamstring and iliopsoas spasticity or providing adequate orthotic support, can further worsen the condition, making long-term mobility and functional independence increasingly difficult.
The following tables provide clinical recommendations for the selection of AFOs based on specific gait classifications in children with spastic cerebral palsy. They include specifications for various orthotic designs, as well as guidance on alignment and key functional components.
The degree of the orthosis effect is denoted as follows:
Very strong effect: ++++
Strong effect: +++
Moderate effect: ++
Mild effect: +
User has no severe internal or external rotation and no severe foot drop
Orthosis Recommendation
Alignment: 0 degrees
Height: slightly above lateral malleolus
User has low activity/weight and no severe rotation
Orthosis Recommendation
Alignment: 0-3 degrees
Height: ¼ to ⅓ of the lower leg
Soft heel strike, flexible forefoot
Ankle joint: free or neutral
User has low activity/weight and slight knee hyperextension
Orthosis Recommendation
Alignment: 3-5 degrees
Height: ⅓ to ½ of the lower leg
Firm heel strike, flexible forefoot
Ankle joint: free or 3-5 degrees
User has low activity/weight and slight knee hyperextension
Orthosis Recommendation
Alignment: 3-5 degrees
Height: ½ of the lower leg
Firm heel strike, flexible forefoot
Ankle joint: free or 3-5 degrees
User has Low activity/weight and slight knee flexion
Orthosis Recommendation
Height: ½ lower leg
Firm heel strike, flexible forefoot
Ankle joint: 0 degrees/ 7 degrees
Not specified (insufficient support for crouch gait patterns)
User has low to high activity/weight, no severe rotation, mild foot deformity, and no contractures
Orthosis Recommendation
Alignment: 0–3 degrees
Height: Standard- Elastic dorsal closure possible
Standard heel strike, flexible forefoot
Ankle joint: standard (varies by fabrication)
Same as type 1 plus slight knee hyperextension
Orthosis Recommendation
Alignment: 3–5 degrees
Height: Standard
Same orthotic features as type 1
Same as type 2
Orthosis Recommendation
Alignment: 3–5 degrees
Height: Standard
Same orthotic features as type 1
User has low to high activity/weight, no severe rotation, mild foot deformity, and no contractures
Orthosis Recommendation
Alignment: 0–3 degrees
Height: Standard
Soft heel strike, flexible forefoot
Ankle joint: standard (varies by fabrication)
Same as type 1 plus slight knee hyperextension
Orthosis Recommendation
Alignment: 5–7 degrees
Height: Standard
Same orthotic features as type 1
Same as type 2
Orthosis Recommendation
Alignment: 5–7 degrees
Height: Standard
Same orthotic features as type 1
Same as type 1 and slight knee flexion
Orthosis Recommendation
Alignment: 0–3 degrees
Same orthotic features as type 1
User has low to high activity/weight, mild internal/external rotation, slight knee hyperextension
Orthosis Recommendation
Alignment: 5–7 degrees
Height: Over gastrocnemius
Firm heel strike, flexible forefoot
Ankle joint: 0 degrees/5–7 degrees/free
User has Low to high activity/weight – Mild internal/external rotation
Orthosis Recommendation
Alignment: 5–7 degrees
Height: Over gastrocnemius
Stiff heel strike, flexible forefoot
Ankle joint: 0 degrees/5–7 degrees/free
User has low to high activity/weight, slight knee flexion, mild internal/external rotation
Orthosis Recommendation
Alignment: 0–3 degrees
Height: Over gastrocnemius
Soft heel strike, stiff forefoot
Ankle joint: 0 degrees/5–7 degrees/free
User has Low to high activity/weight and mild internal/external rotation acceptable
Orthosis Recommendation
Alignment: 3-5 degrees
Height: Over gastrocnemius (with condyle embedding if needed)
Soft heel strike, flexible forefoot
Ankle joint: free/ 0 degrees
User has low to high activity/weight, mild internal/external rotation, slight knee hyperextension
Orthosis Recommendation
Alignment: 5-7 degrees
Height: Over gastrocnemius
Firm heel strike, flexible forefoot
Ankle joint: 0 degrees/5–7 degrees/free
User has low to high activity/weight, mild internal/external rotation acceptable
Orthosis Recommendation
Alignment: 5–7 degrees
Height: Over gastrocnemius
Stiff heel strike, flexible forefoot
Ankle joint: 0 degrees/5–7 degrees/free
User has low activity/weight, mild internal/external rotation, slight knee flexion
Orthosis Recommendation
Alignment: 0-3 degrees
Height: Over gastrocnemius
Soft heel strike, stiff forefoot
Ankle joint: 5 degrees/0-3 degrees/7 degrees
User has low activity/weight, mild internal/external rotation, slight knee flexion
Orthosis Recommendation
Alignment: 0-3 degrees
Height: Over gastrocnemius
Soft heel strike, stiff forefoot
Ankle joint: 5 degrees/0-3 degrees/7 degrees
AFOs are essential tools in the multidisciplinary approach to treating gait disorders in spastic CP. Their success depends on accurate gait classification, careful patient profiling, and appropriate orthotic selection tailored to each individual’s clinical presentation and functional goals. Future research should continue to explore long-term outcomes, user compliance, and technological advancements to further refine orthotic interventions for this population.
Nader Ibrahim is an O&P student at New Cairo Technological University, Egypt. This research was completed as a project during his studies.