Reinald Brunner

Comparison of a dynamic and a hinged ankle–foot orthosis by gait analysis in patients with hemiplegic cerebral palsy

We studied the effect of a dynamic ankle-foot orthosis (d-AFO) on gait in 12 hemiplegic cerebral palsy patients. Sagittal plane kinematic and kinetic data of walking with the d-AFO were compared with walking barefoot, walking in a hinged ankle-foot orthosis (h-AFO) with a plantarflexion block and normal values. All patients had excessive plantarflexion and initial toe contact when walking barefoot. The d-AFO did not improve gait significantly whereas the h-AFO did. The benefits of controlling plantarflexion by a longer lever arm fror the h-AFO to the proximal calf included a heel-toe gait pattern, reduced plantarflexion, increased step and stride length and reduced power absorption.

Joint stiffness and gait pattern evaluation in children with Down syndrome

Hypotonia, ligament laxity and motor alterations are characteristic for patients with Down syndrome (DS). The purpose of this study was the evaluation of typical gait pattern of subjects with Down syndrome and the quantification of their joint stiffness, connected with ligament laxity and hypotonia, as a possible compensation. 98 children with DS (mean age: 11.7 years; range: 6-15 years) and 30 healthy children (control group (CG); mean age: 11 years; range: 5-13 years) underwent full 3D gait analysis at self-selected speed. Subjects with DS walked with more hip flexion during the whole gait cycle, knee flexion in stance phase, a limitation of the knee range of motion, and plantarflexion of the ankle at initial contact. Ankle power was limited as evident in terminal stance and pre-swing, represented by a low propulsive capacity at push-off, too. Hip joint stiffness was increased in general in patients with DS versus normal subjects while ankle joint stiffness revealed a lower value instead.

Evaluating upper body movements during gait in healthy children and children with diplegic cerebral palsy.

Movements of the lower limbs during gait have been analysed extensively whereas data on upper body movements are scarce. The aim of this study was to evaluate upper body movements during gait in nine healthy children and 10 children with diplegic cerebral palsy. Children were investigated using a full-body marker set to calculate the upper body kinematics of trunk and arms. When the healthy children were compared with the children with cerebral palsy, the latter compensated more for their gait deviations and were less stable. This was expressed by their greater variability in arm movements and increased movements at the thorax. The thorax showed an increased forward tilt with greater range of motion over the gait cycle. The shoulders were more abducted with increased elbow flexion. Gait analysis with the full-body marker set has offered prospects for a better understanding of compensatory mechanisms for the pathological gait pattern in children with diplegic cerebral palsy.

Acute effects of intramuscular aponeurotomy on rat gastrocnemius medialis: Force transmission, muscle force and sarcomere length

Acute effects of intramuscular aponeurotomy on muscle force and geometry as a function to muscle length were studied in rat m. gastrocnemius medialis (GM). Acutely after aponeurotomy, activation of the muscle at increasing lengths (acute trajectory) showed a spontaneous and progressive but patial tearing of the connective tissue interface between the fibres inserting directly proximally and distally to the location of the section. After this the muscle consisted morphologically of a stable proximal and a distal part (post-aponeurotomy). Post-aponeurotomy mean active sarcomere length within fibres of the proximal part was shown to be unaffected. In contrast, mean sarcomere length within the distal part was reduced substantially after aponeurotomy. However active sarcomeres in the distal part were still attaining higher lengths with increasing muscle lengths (p<0.005), indicating myofascial force transmission through the intact part of the connective tissue interface of the muscle parts. Post-aponeurotomy optimum muscle force was reduced substantially to less than 45% of pre-aponeurotomy values. During the acute trajectory the muscle yielded approximately 20% higher forces than post-aponeurotomy, indicating that myofascial force transmission was related to the area of connective tissue interface. It is concluded that after aponeurotomy of the proximal aponeurosis of rat GM, fibres without direct myotendinous connection to the origin of the muscle are still able to contribute to muscle force. As the magnitude of reduction in muscle force can only be explained partially by the spontaneous rupture of the connective tissue interface between proximal and distal muscle part, other factors causing a decrease of muscle force are present. Clinical implication of acute effects of intramuscular aponeurotomy are discussed.

Effects of plantarflexion on pelvis and lower limb kinematics

Modelling the effect of soleus and gastrocnemius contractions against the floor resistance in a forward dynamics simulation revealed that hip flexion, internal rotation and adduction together with external pelvic rotation could be attributed to a direct, but distant effect of triceps surae contraction. Knee flexion smoothed out the effect. To validate this clinically relevant biomechanical observation, ankle plantar flexion was correlated with hip and pelvic rotation retrospectively in children with spastic cerebral palsy. In 49 children with spastic hemiplegia, plantar flexion showed a significant correlation with increased pelvic retraction and hip internal rotation. In contrast, in 47 children with spastic diplegia no significant effect of the triceps surae on hip and pelvis kinematics was found. Bilateral hip and knee flexion in diplegia appeared to prevent the proximal effect of the triceps surae seen in the hemiplegics. In diplegia triceps surae overactivity did not appear to be a significant cause of internal rotation gait.

Tibialis anterior tendon shortening in combination with Achilles tendon lengthening in spastic equinus in cerebral palsy

Equinus is the commonest deformity in cerebral palsy (CP). Many different surgical procedures have been described for the treatment of spastic equinus. In long standing equinus deformities the tibialis anterior muscle becomes elongated which is one reason for muscle weakness. Surgical tendon shortening of the tibialis anterior tendon was therefore introduced to rebalance muscle strength. All patients with CP who had a tibialis anterior tendon shortening (TATS) in combination with a tendo Achilles lengthening (TAL) were included in this study. A total of 29 patients had 30 surgical interventions (21 hemiplegic patients: 14 boys/7 girls, age 9-22 years; mean 15.2 years; 5 diplegics and 3 quadriplegics; 5 boys/3 girls, age 7-37.5 years; mean 14.8 years). Fifteen patients had additional surgery (soft tissue or bony procedures). The TATS was performed at the distal insertion with transosseous tendon fixation in the medial cuneiform bone at the original place. Movement Analysis Profile (MAP) for ankle dorsi-/plantarflexion, Gait Profile Score (GPS), Gait Deviation Index (GDI), and Gillette Gait Index (GGI) improved significantly for all patients compared pre- to postoperatively. In 93% of the patients active dorsiflexion of the ankle was possible postoperatively. We conclude that TATS in combination with TAL in spastic equinus in CP is a safe procedure and improves but not completely corrects foot positioning during gait. For the treatment of spastic equinus in CP we recommend shortening of the elongated antagonist (TATS) in combination with lengthening of the short agonist (TAL) for achieving optimal postoperative function.

The pediatric LCP hip plate for fixation of proximal femoral osteotomy in cerebral palsy and severe osteoporosis.

Background Hip dislocation or subluxation together with poor nutrition, reduced weight bearing, and osteoporosis is a frequent condition in severe cerebral palsy (CP). Severe osteoporosis may cause difficulties in fixing a proximal femoral osteotomy with a conventional blade plate. The Pediatric locking compression plate (LCP) Hip Plate system offers better grip and more stable fixation. Methods Fifty-three proximal femoral osteotomies, alone or as part of a more complex surgical intervention, were performed in 28 patients (17 boys and 11 girls, age at surgery average 10.4 y, 3 to 19 y). All children suffered from CP (24 quadriplegics, 2 diplegics, and 2 hemiplegics) with Gross Motor Function Classification System levels: 3× III, 3× IV, and 22× V. This cohort was compared with a historical (conventional AO blade plate) group (38 patients with 53 operative interventions, 24 girls and 14 boys, age at surgery average 9.8 y, 3 to 18.5 y, Gross Motor Function Classification System levels: 4× III, 5× IV, and 29× V; 34 quadriplegics, 3 diplegics, and 1 hemiplegic). Results The operative interventions of both cohorts that are performed are comparable considering the average amount of varisation and derotation. Operations with the conventional AO blade plate were 17.2 minutes shorter on average and the blood loss was 45.6 mL less on average. Radiologically, 19.6% of the patients had signs of complete consolidation with the LCP Hip Plate 6 weeks after surgery (vs. 91.1% of the patients of the historical cohort, P <0.001) but all osteotomies in both groups were completely consolidated by 12 weeks. In the LCP cohort in 3 patients (10.7%) full weight bearing was allowed immediately after the operation. Conclusions Both implants, the Pediatric LCP Hip Plate and the conventional AO blade plate, produce similar results regarding fixation and correction of the neck-shaft angle. The consolidation rate 6 weeks postoperatively using the LCP plate is lower than with the conventional blade plate, whereas equivalent healing at 3 months was found. Hence, LCP plate removal is recommended not earlier than 6 months after surgery despite good callus formation on x-ray. Level of Evidence Level III.

Acute and long-term effects on muscle force after intramuscular aponeurotic lengthening.

Intramuscular aponeurotic lengthening of muscles or intramuscular tenotomy involves bisecting the connective tissue fibers of the aponeurosis or tendon within the muscle belly. Because of its superficial location in the muscle, the aponeurosis may be bisected without damaging muscle fibers. Despite the existence of common operative methods for gaining length in short muscles, the effects on force and muscle function have not been studied. For this purpose animal experiments were performed. The medial gastrocnemius muscle of six male Wistar rats was lengthened by cutting the proximal aponeurosis at 50% of its length perpendicularly to the collagen fibers. The length gain was maintained by 3 days of cast immobilization at maximal dorsiflexion of the ankle. The long-term effect of the treatment was studied after 6 weeks and compared with 10 untreated controls and with six sham operated animals. The muscle was isolated in situ, and the force length characteristics were determined. In the untreated controls, the aponeurotomy was performed and the length force experiment was repeated to study the acute effects. The aponeurotic lengthening led acutely to a temporary loss of force because of an incomplete connection of the distal part of the muscle to the proximal insertion, but force recovered completely within 6 weeks. Although results from animal experiments cannot be transferred directly to humans, the principles of physiology are similar. Thus, for clinical use, aponeurotic lengthening should be considered if muscle force needs to be preserved. However, the drop of muscle force after surgery must be respected when mobilizing the patient during the postoperative rehabilitation program.

Acute effects of intramuscular aponeurotomy and tenotomy on multitendoned rat EDL: Indications for local adaptation of intramuscular connective tissue

Intervention with the continuity of the tendon and part of the muscle fibers allows investigation of myofascial force transmission. The present study investigates the effects of proximal aponeurotomy on length‐force characteristics and the geometry of the extensor digitorum longus (EDL) muscle, and compares those effects with the effects of both distal tenotomy (TT) and intramuscular fasciotomy (IF) of the EDL. After proximal aponeurotomy, the intramuscular connective tissue ruptured spontaneously below the location of intervention. Due to this rupturing, a gap developed within the proximal aponeurosis. The fibers that were continuous with the tendon at only one end were substantially shorter than before the intervention. Optimum muscle force was reduced by 29%. After distal TT (of heads II–IV) a gap developed within the muscle belly. This gap increased at higher muscle lengths. However, the length of the gap was much smaller than after aponeurotomy. Despite the TT‐related gap, there was no rupturing of intramuscular connective tissue at the interface between heads IV and V, as there was after proximal aponeurotomy. The effects of TT on length‐force characteristics and on lengths of fibers continuous with the tendon at only one end were much less compared to the effects of aponeurotomy. Subsequent IF for two‐thirds the length of the interface between heads IV and V resulted in changes similar to the effects of proximal aponeurotomy plus rupture. The contrast regarding the occurrence of intramuscular connective tissue rupture indicates increased failure strength of the intramuscular connective tissue at distal locations. It is hypothesized that for multitendoned muscles in vivo, local shear and stress deformations will initiate local adaptation of the intramuscular connective tissue. Anat Rec 266:123–135, 2002.

Best Clinical Practice in Botulinum Toxin Treatment for Children with Cerebral Palsy

Botulinum toxin A (BoNT-A) is considered a safe and effective therapy for children with cerebral palsy (CP), especially in the hands of experienced injectors and for the majority of children. Recently, some risks have been noted for children with Gross Motor Classification Scale (GMFCS) of IV and the risks are substantial for level V. Recommendations for treatment with BoNT-A have been published since 1993, with continuous optimisation and development of new treatment concepts. This leads to modifications in the clinical decision making process, indications, injection techniques, assessments, and evaluations. This article summarises the state of the art of BoNT-A treatment in children with CP, based mainly on the literature and expert opinions by an international paediatric orthopaedic user group. BoNT-A is an important part of multimodal management, to support motor development and improve function when the targeted management of spasticity in specific muscle groups is clinically indicated. Individualised assessment and treatment are essential, and should be part of an integrated approach chosen to support the achievement of motor milestones. To this end, goals should be set for both the long term and for each injection cycle. The correct choice of target muscles is also important; not all spastic muscles need to be injected. A more focused approach needs to be established to improve function and motor development, and to prevent adverse compensations and contractures. Furthermore, the timeline of BoNT-A treatment extends from infancy to adulthood, and treatment should take into account the change in indications with age.