Theuseofgaitanalysisin orthopaedic surgical treatment in children with cerebral palsy

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1 Theuseofgaitanalysisin orthopaedic surgical treatment in children with cerebral palsy Aim of treatment Correction of functional disorder Requires analysis of function Basis for decision making Basis for decision making Results from clinical(static) examination do not correlate with functional(dynamic) assessment McMulkin ML et al. Correlation of static to dynamic measures of lower extremity range of motion in cerebral palsy and control populations. 2 Clinical examination: what is possible Functional assessment: what happens Aim: correction of function Basis for decision making Normal stance Analysis of disorder in respect of normal function: ground reaction force Knowledge of normal function presupposed: joint capsule iliacus extensor moment Perry 1984 Normal function extensor moment dorsiflexor moment joint capsule gastrocnemii ischiocrurals? triceps surae: soleus gastrocnemii 1

2 Foot gastrocnemii accelerate leg for swing A.Hof,24 soleus controls position of tibia in space and accelerates centre of gravity External flexion- Tibial muscles Triceps dorsi- moment Peroneal muscles surae Spasticity 2

3 - Weakness Problem muscles: Foot: triceps surae and other foot muscles Knee: extensors Hamstrings Hip: extensors and rotators Hip: Adductors Older patients: Decompensation Young patients: Plantar flexion- knee extension couple Loss of the plantar flexion- knee extension couple(1) Loss of the plantar flexion- knee extension couple(2) Giving way of triceps Heel cord lengthening (surgical) Or fall spontaneously normal mild hyperextension unstable normal mild hyperextension Unstable (tendon overlength) 3

4 Giving way of other foot muscles (tib. post., peron. longus etc.) Lever arm dysfunction Giving way of foot muscles Tib. post. overactivity ext degrees int 4c.Footrotation 4b. Foot progression ext degrees int Knee extensor overlength/ weakness 4

5 Giving way of knee extensors Active extension lag Knee flexion deformity Problem muscles: Foot: triceps surae and other foot muscles Knee: extensors Hamstrings Hip: extensors and rotators Hip: Adductors flex Nm/kg ext flex Nm/kg ext 7b. Hip ext/flex moment 8b. Knee ext/flex moment Role of hamstrings? Correlation of knee extensor moment with knee flexor moment: Hamstrings: Hip extensors Role of hamstrings? Cocontraction of knee extensors may increase efficacy of hamstrings(hypothesis) 4765 cerebral palsy internal rotation gait Problem muscles: Foot: triceps surae and other foot muscles Knee: extensors Hamstrings Hip: extensors and rotators Hip: Adductors muscular part? not adductors/ hamstrings Arnold AS, Asakawa DJ, Delp SL: Do the hamstrings and adductors contribute to excessive internal rotation of the hip in persons with cerebral palsy? Gait Posture, 2, 3:

6 Functional hip malrotation Think of triceps surae - Older patients: Decompensation In hemiplegics not in diplegics Animation: Carlo Frigo, Politechnico, Milano Giving way of hip extensors and external rotators Hip flexion deformity Increased internal rotation Problem muscles: Foot: triceps surae and other foot muscles Knee: extensors Hamstrings Hip: extensors and rotators Hip: Adductors Hip adduction Horizontal plane kinematics ab d degrees add b. Hip ab-/adduction Pseudo-adduction (caused by pelvic motion) abd d egrees add 2b.Hip ab-/adduction True adduction 6

7 Torsions Rotational position of pelvis Rotation of hip(rotational position of knee) Offset = Torsion Amplitude = funct. component ext degrees int 2c. Hip rotation Hip rotation(kneeing in) Kneeing in ext degrees int c. Pelvic rotation Bilateral derotation? ext degrees int c. Hip rotation Torsions Tibial and foot torsions guesswork Treatment General Toe walking Foot strike Foot deformity Equinus Normal position Knee flexion Stable stance leg (enough time to prepare leg for swing) Varus- or valgus? Unstable stance leg (notimetopreparelegfor swing) 7

8 Conservative Most important stabiliser Orthosis provides stability and stretching save our soleus To prevent foot deformities Equinus foot Beware of bilateral soleus weakening Spasticity management Selective dorsal rhizotomy Treatment Spasticity Weakness praeop 6mpostop from Gage J.: The traetment of gait problems in cerebral palsy Gain of muscle length Conservative Muscle force Effect of surgical lengtheing Hypothesis Botulinum toxin(temporary weakening): ideal in functional shortening force range of motion surgical lengthening overly short normal overly long Precondition: impeding muscle/ muscle group can be defined Does not lengthen but reduces resistence atrophy atrophy Effect comes and goes length 8

9 surgical result not simulated(no lengthening) degrees Ankle %gaitcycle degrees Knee %gait cycle degrees Hip %gaitcycle Lever arm(femur): (coronal plane) anteversion reducesleverarmto75 9

10 Footasleverarm Correction of lever arm dysfunction Lever arm(tibia): Leverarmin direction of gait B A Aim: foot aligned to direction of gait Supramelleolar osteotomy for external/ internal rotation LCP-plate or external fixateur (immediate weight bearing) Plantar support Correction of lever arm dysfunction Conservative OSSA Nancy- Hylton Lever arm(foot): AFO Calcaneal lengthening (Evans) Surgical Calcaneocuboidal fusion Subtalar fusion Treatment Spasticity Weakness: tendon shortenings Achilles tendon shortening Achilles tendon shortening Prerequisite: plantarflexion of ~2 Suture under good tension Protection for 3-6 months(cast, stiff AFO all day) Problems: -Suturegivesway - Stretchability of muscle - Protection Foot preparation Difficult procedure Immediate stretching possible About6weeksof frame 1

11 Achilles tendon shortening Achilles tendon shortening Aftercare 6 weeks lower leg cast technique of suture 4 weeks without weight bearing readapation of tendon under tension Rigid AFO for 3 months, optionally longer in case of danger of relapse Full tension in 2 of plantar flexion Achilles tendon shortening Muscle shortenings in CP Conclusion out of kinematics and kinetics Preliminary results: 9a. Ankle dorsiflexion 4 degrees degrees c. Total ankle power -1-2 plant c. Total ankle power watt/kg 1 abs watt 2 gen 4 gen c. Total ankle power 4 abs gen plant plant -2 watt dorsi dorsi dorsi degrees Achilles tendon shortening (n=24) a. Ankle dorsiflexion abs 9a. Ankle dorsiflexion Adequate triceps power only in maximal dorsiflexion (tendon overlength) Adequate triceps power at correct dorsiflexion angle after heel cord shortening 4594a/c Spina bifida Re-balancing of hamstrings and knee extensors Re-balancing of hamstrings and knee extensors 2. Knee extensor shortening 2. Knee extensor shortening (+ Supracondylar extension osteotomy) (+ Supracondylar extension osteotomy) 11

12 Aftercare Spasticity Weakness 12

13 Good& consistent long term results Summary 13