G. R. Nattrass

The Functional Mobility Scale (FMS).

We devised a new Functional Mobility Scale (FMS) to describe functional mobility in children with cerebral palsy, as an aid to communication between orthopaedic surgeons and health professionals. The unique feature of the FMS is the freedom to score functional mobility over three distinct distances, chosen to represent mobility in the home, at school and in the wider community. We examined the construct, content, and concurrent validity of the FMS in a cohort of 310 children with cerebral palsy by comparing the FMS to existing scales and to instrumented measures of physical function. We demonstrated the scale to be both valid and reliable in a consecutive population sample of 310 children with cerebral palsy seen in our tertiary referral center. The FMS was useful for discriminating between large groups of children with varying levels of disabilities and functional mobility and sensitive to detect change after operative intervention.

Analgesic effects of botulinum toxin A: a randomized, placebo-controlled clinical trial.

Postoperative pain in children with spastic cerebral palsy (CP) is often attributed to muscle spasm and is difficult to manage using opiates and benzodiazepines. Adductor‐release surgery to treat or prevent hip dislocation in children with spastic CP is frequently performed and is often accompanied by severe postoperative pain and spasm. A double‐blinded, randomized, placebo‐controlled clinical trial of 16 patients (mean age 4.7 years) with a mainly spastic type of CP (either diplegic or quadriplegic in distribution) was used to test the hypothesis that a significant proportion of postoperative pain is secondary to muscle spasm and, therefore, might be reduced by a preoperative chemodenervation of the target surgical muscle by intramuscular injection of botulinum toxin A (BTX/A). Compared with the placebo, BTX/A was found to be associated with a reduction in mean pain scores of 74% (P<0.003), a reduction in mean analgesic requirements of approximately 50% (P<0.005), and a reduction in mean length of hospital admission of 33% (P<0.003). It was concluded that an important component of postoperative pain in the patient population is due to muscle spasm and this can be managed effectively by preoperative injection with BTX/A. These findings may have implications for the management of pain secondary to muscle spasm in other clinical settings.

Correction of severe crouch gait in patients with spastic diplegia with use of multilevel orthopaedic surgery.

BACKGROUND Severe crouch gait in patients with spastic diplegia causes excessive loading of the patellofemoral joint and may result in anterior knee pain, gait deterioration, and progressive loss of function. Multilevel orthopaedic surgery has been used to correct severe crouch gait, but no cohort studies or long-term results have been reported, to our knowledge. METHODS In order to be eligible for the present retrospective cohort study, a patient had to have a severe crouch gait, as defined by sagittal plane kinematic data, that had been treated with multilevel orthopaedic surgery as well as a complete clinical, radiographic, and instrumented gait analysis assessment. The surgical intervention consisted of lengthening of contracted muscle-tendon units and correction of osseous deformities, followed by the use of ground-reaction ankle-foot orthoses until stable biomechanical realignment of the lower limbs during gait was achieved. Outcome at one and five years after surgery was determined with use of selected sagittal plane kinematic and kinetic parameters and valid and reliable scales of functional mobility. Knee pain was recorded with use of a Likert scale, and all patients had radiographic examination of the knees. RESULTS Ten subjects with severe crouch gait and a mean age of 12.0 years at the time of surgery were studied. After surgery, the patients walked in a more extended posture, with increased extension at the hip and knee and reduced dorsiflexion at the ankle. Pelvic tilt increased, and normalized walking speed was unaltered. Knee pain was diminished, and patellar fractures and avulsion injuries healed. Improvements in functional mobility were found, and, at the time of the five-year follow-up, fewer patients required the use of wheelchairs or crutches in the community than had been the case prior to intervention. CONCLUSIONS Multilevel orthopaedic surgery for older children and adolescents with severe crouch gait is effective for relieving stress on the knee extensor mechanism, reducing knee pain, and improving function and independence.

High- or low-technology measurements of energy expenditure in clinical gait analysis?

The repeatability of energy‐expenditure measurements were studied in five children and four adults without disabilities using the Cosmed K4 (high technology). The ability to detect change in measurements was compared between this instrument and the Physiological Cost Index (PCI; low technology). The results of repeatability (95% range) for oxygen cost were 13.1% in children and 13% in adults. In contrast, the SD of PCI was 6 to 72% of the mean in adults and wider in children (91%; 95% range). The validity of PCI as an outcome measure was questioned. In addition, 177 children with motor disability were prospectively studied using the Cosmed K4. Previous experience with the Cosmed K2 (intermediate technology) helped to develop a practical and repeatable protocol for testing children with disability using the Cosmed K4. The protocol commenced with 5 minutes of rest to achieve baseline values of heart rate and oxygen consumption, followed by 10 minutes of continuous walking at a self‐selected speed on a 10–metre level oval walking track. The test concluded with 5 minutes of rest to monitor the return to baseline values. Ninety‐one percent of the children with disability quickly reached a steady‐state of oxygen consumption and carbon‐dioxide production. The carbon‐dioxide sensor in the Cosmed K4 has enabled a new group of severely involved children with cerebral palsy (9%) to be defined. These children have been termed ‘physiologically marginal ambulators’.

Accuracy of intramuscular injection of botulinum toxin A in juvenile cerebral palsy: a comparison between manual needle placement and placement guided by electrical stimulation.

Most clinicians who perform botulinum toxin A injections for children with cerebral palsy do so using the “free-hand” or manual technique without using radiologic or electrophysiologic guidance to aid needle placement. The objective of this study was to investigate the accuracy of manual needle placement compared with needle placement guided by electrical stimulation. A total of 1,372 separate injections for upper and lower limb spasticity were evaluated in 226 children with cerebral palsy. The accuracy of manual needle placement compared with electrical stimulation was acceptable only for gastroc-soleus (>75%); it was unacceptable for the hip adductors (67%), medial hamstrings (46%), tibialis posterior (11%), biceps brachii (62%), and forearm and hand muscles (13% to 35%). The authors recommend using electrical stimulation or other guidance techniques to aid accurate needle placement in all muscles except the gastroc-soleus. Further study is needed to determine whether more accurate injecting will lead to better functional outcomes and more efficient use of botulinum toxin A.

Does botulinum toxin a combined with bracing prevent hip displacement in children with cerebral palsy and "hips at risk"? A randomized, controlled trial.

BACKGROUND Cerebral palsy is the most common cause of childhood physical disability in developed countries, affecting two children per 1000 live births. Hip displacement affects about one-third of children with cerebral palsy and may result in pain, deformity, and impaired function. The prevention of hip displacement has not been studied in a randomized trial as far as we know. METHODS A randomized, controlled trial was conducted to examine the effect of intramuscular injections of botulinum toxin A combined with use of a variable hip abduction brace on the progression of hip displacement in children with cerebral palsy. The patients in the treatment group received injections of botulinum toxin A to the adductor and hamstring muscles every six months for three years and were prescribed a hip abduction brace to be worn for six hours per day. In the control group, no hip bracing was used nor were injections performed. The primary outcome measure was hip displacement from the acetabulum as determined by serial measurements of the migration percentage. RESULTS Ninety children with bilateral cerebral palsy and so-called hips at risk (a migration percentage of >10% but <40%) were entered into the study. Fifty-nine patients were boys, and the mean age was three years. Progressive hip displacement, as determined by serial measurements of the migration percentage, was found in both the treatment and control groups. The rate of hip displacement was reduced in the treatment group by 1.4% per year (95% confidence interval, -0.6% to 3.4%; p = 0.16) when weighted for the uncertainty in rates due to the differing numbers of migration percentage measurements per subject. CONCLUSIONS There may be a small treatment benefit for the combined intervention of intramuscular injection of botulinum toxin A and abduction hip bracing in the management of spastic hip displacement in children with cerebral palsy. However, progressive hip displacement continued to occur in the treatment group, and our data do not support recommending this treatment.

Hip surveillance in children with cerebral palsy: IMPACT ON THE SURGICAL MANAGEMENT OF SPASTIC HIP DISEASE

We studied prospectively the impact of a hip surveillance clinic on the management of spastic hip disease in children with cerebral palsy in a tertiary referral centre. Using a combination of primary clinical and secondary radiological screening we were able to detect spastic hip disease at an early stage in most children and to offer early surgical intervention. The principal effect on surgical practice was that more preventive surgery was carried out at a younger age and at a more appropriate stage of the disease. The need for reconstructive surgery has decreased and that for salvage surgery has been eliminated. Displacement of the hip in children with cerebral palsy meets specific criteria for a screening programme. We recommend that hip surveillance should become part of the routine management of children with cerebral palsy. The hips should be examined radiologically at 18 months of age in all children with bilateral cerebral palsy and at six- to 12-monthly intervals thereafter. A co-ordinated approach by orthopaedic surgeons and physiotherapists may be the key to successful implementation of this screening programme.

Hip displacement in spastic cerebral palsy: Repeatability of radiologic measurement

Radiologic measures of migration percentage (MP) and acetabular index (AI) taken from plain radiographs of the pelvis are the most commonly used tools for determining hip displacement and management options in children with cerebral palsy and spastic hip disease. This study determined interrater and intrarater reliability of MP and AI on pelvic radiographs chosen to represent a wide range of age (11 months to 8 years 5 months), MP (0%–56%), and AI (9°–33°). The study demonstrated that an experienced rater would be expected to measure MP on a single radiograph to within ±5.8% of the true value and a change in MP between two radiographs taken at different times to within ±8.3% of the true value. Similarly for AI, the measurement error for a typical rater would be within ±2.6°on a single reading and ±3.7° if recording change between two occasions. The authors believe that the results indicating true change are acceptable in clinical practice, provided treatment decisions are based on a series of radiographs taken at 6-month intervals, methods and training are standardized, and consistent raters are used.

The effect of botulinum toxin type A and a variable hip abduction orthosis on gross motor function: a randomized controlled trial.

Hip displacement is the second most common deformity after equinus in children with cerebral palsy (CP), and may result in dislocation, pain, fixed deformity and loss of function. We studied the combined effects of intramuscular injections of botulinum toxin type A (BTX‐A) to the adductors and hamstrings and a variable hip abduction orthosis (SWASH), on gross motor function, hip displacement and progression to surgery, in a randomized clinical trial. Thirty‐nine children, with bilateral spastic cerebral palsy, and mean age 3 years + 2 months (range 1 year + 7 months–4 years +10 months) entered the trial. Gross Motor Function Classification System (GMFCS) levels were as follows: one child was level II, 11 were level III, 13 were level IV and 14 were level V. After concealed randomization, 20 were allocated to the control group and 19 to the intervention group. Thirty‐five children completed the follow up at 1 year. The novel intervention group received up to 4.0 U BOTOX®/kg/muscle, 16 U/kg/body weight every 6 months plus the use of a SWASH brace. The control group received clinical best practice comprising physiotherapy but no hip abduction bracing. Both groups showed improvements in total Gross Motor Function Measure (GMFM) score [mean 6.0% BTX‐A group; 6.1% Control; 95% CI – 6.7, 6.5 (NS)], however, there was no additional treatment effect for the study group. There were similar improvements on GMFM goal scores and GMFM‐66 scores, but again no additional treatment effect was observed. Multiple regression of change in total GMFM by GMFCS classification for each group showed greater improvement in the total scores from baseline in the BTX‐A/SWASH treated group than the control group. In the first year, nine children (two in the intervention group and seven in the control group) required soft tissue surgery because of progressive hip migration in excess of 40%. A longer‐term follow up of a larger cohort may be required to determine the effect of the combined treatment on hip displacement.

Femoral derotation osteotomy in spastic diplegia: PROXIMAL OR DISTAL?

We describe the results of a prospective study of 28 children with spastic diplegia and in-toed gait, who had bilateral femoral derotation osteotomies undertaken at either the proximal intertrochanteric or the distal supracondylar level of the femur. Preoperative clinical evaluation and three-dimensional movement analysis determined any additional soft-tissue surgery. Distal osteotomy was faster with significantly lower blood loss than proximal osteotomy. The children in the distal group achieved independent walking earlier than those in the proximal group (6.9 +/- 1.3 v 10.7 +/- 1.7 weeks; p < 0.001). Transverse plane kinematics demonstrated clinically significant improvements in rotation of the hip and the foot progression angle in both groups. Correction of rotation of the hip was from 17 +/- 11 degrees internal to 3 +/- 9.5 degrees external in the proximal group and from 9 +/- 14 degrees internal to 4 +/- 12.4 degrees external in the distal group. Correction of the foot progression angle was from a mean of 10.0 +/- 17.3 degrees internal to 13.0 +/- 11.8 degrees external in the proximal group (p < 0.001) compared with a mean of 7.0 +/- 19.4 degrees internal to 10.0 +/- 12.2 degrees external in the distal group (p < 0.001). Femoral derotation osteotomy at both levels gives comparable excellent correction of rotation of the hip and foot progression angles in children with spastic diplegia.