Effect of derotation osteotomy of the femur on hip and pelvis rotations in hemiplegic and diplegic children

Clinical and Gait Parameters Related to Pelvic Retraction in Patients with Spastic Hemiplegia

Pelvic retraction during walking is a common finding seen in patients with spastic hemiplegia. However, potential factors related to this condition have not been comprehensively examined in a systemic manner in previous studies. The purpose of this study was to elucidate any clinical and gait parameters related to pelvic retraction in patients with hemiplegic cerebral palsy. A total of 212 independent ambulatory patients were enrolled in the study. Group I consisted of 113 patients who had persistent pelvic retraction, and Group II of 99 with a normal range of pelvic rotation throughout the gait cycle as evidenced by kinematic analysis. A multivariate logistic regression analysis using a clustering technique was performed, with use of eight gait factors and five clinical factors. Decreased ankle dorsiflexion, increased hip internal rotation, increased anterior pelvic tilt, the Winters classification type II, and asymmetrical posturing of the upper extremity during gait were found to be related to pelvic retraction. This is the only study including a broader array of assessment domains of both clinical and gait parameters with a considerably large and homogenous population with hemiplegia. Further studies will be needed to see whether the rectification of those parameters may improve abnormal gait and pelvic retraction in hemiplegia.

Changes in gait parameters after femoral derotational osteotomy in cerebral palsy patients with medial femoral torsion

Medial femoral torsion (MFT) is a common pathologic gait in cerebral palsy (CP) children that can be corrected by femoral derotational osteotomy (FDO). It is not clearly known as to how much various gait parameters change after FDO. The aim of this study was to quantify changes in gait parameters after FDO. The study group included 19 young CP patients (28 limbs, age<20 years, average age: 13.2 years) with symptomatic MFT, treated with distal FDO. The study group was divided into two groups: the unilateral FDO group (UG) and the bilateral FDO group (BG). The mean degree of derotation was 24.6° (25.0° for UG, 24.4° for BG). Pre-FDO and post-FDO values of Staheli's rotational profiles and kinematic data were compared. A paired t-test and Pearson's correlation were used for statistical analysis. The mean internal hip rotation was 71.4±6.9° before surgery and 48.6±10.7° after surgery in the UG (P<0.05) and it was 63.8±15.8° before surgery and 40.9±9.2° after FDO in the BG (P<0.05). The change in the foot progression angle (FPA) was 12.9° in the UG group (P<0.05) and 12.6° in the BG group (P<0.05). The degree of FPA had changed by about a half of the surgical derotation angle. Changes in the mean hip rotation during gait were 14.8° in the UG (P<0.05) and 6.7° in the BG (P<0.05) groups. The overall pelvic rotation was not changed after surgery. However, in patients with preoperative compensatory pelvic rotation of more than 5°, there was a change of 5.3±4.8° in the UG and 6.6±1.54° in the BG after surgery (P<0.05). There was also a trend showing that the younger the patient, the more the pelvic rotation changed (P=0.069). In-toeing gait because of MFT improved with FDO in CP patients. The expected degree of postoperative correction of FPA and hip rotation is about a half of the FDO degree. The degree of compensatory pelvic rotation should be considered to determine the correction angle of FDO, especially in young patients with preoperative pelvic rotation of more than 5°.

A Systematic Review of the Effects of Single-Event Multilevel Surgery on Gait Parameters in Children with Spastic Cerebral Palsy

BACKGROUND

Three-dimensional gait analysis (3DGA) is commonly used to assess the effect of orthopedic single-event multilevel surgery (SEMLS) in children with spastic cerebral palsy (CP).

PURPOSE

The purpose of this systematic review is to provide an overview of different orthopedic SEMLS interventions and their effects on 3DGA parameters in children with spastic CP.

METHODS

A comprehensive literature search within six databases revealed 648 records, from which 89 articles were selected for the full-text review and 24 articles (50 studies) included for systematic review. The Oxford Centre for Evidence-Based Medicine Scale and the Methodological Index for Non-Randomized Studies (MINORS) were used to appraise and determine the quality of the studies.

RESULTS

Except for one level II study, all studies were graded as level III according to the Oxford Centre for Evidence-Based Medicine Scale. The MINORS score for comparative studies (n = 6) was on average 15.7/24, while non-comparative studies (n = 18) scored on average 9.8/16. Nineteen kinematic and temporal-distance gait parameters were selected, and a majority of studies reported improvements after SEMLS interventions. The largest improvements were seen in knee range of motion, knee flexion at initial contact and minimal knee flexion in stance phase, ankle dorsiflexion at initial contact, maximum dorsiflexion in stance and in swing phase, hip rotation and foot progression angles. However, changes in 3DGA parameters varied based on the focus of the SEMLS intervention.

DISCUSSION

The current article provides a novel overview of a variety of SEMLS interventions within different SEMLS focus areas and the post-operative changes in 3DGA parameters. This overview will assist clinicians and researchers as a potential theoretical framework to further improve SEMLS techniques within different SEMLS focus groups. In addition, it can also be used as a tool to enhance communication with parents, although the results of the studies can't be generalised and a holistic approach is needed when considering SEMLS in a child with spastic CP.

The effect of postural control and balance on femoral anteversion in children with spastic cerebral palsy

[Purpose] The aim of the study was to investigate the relationships between femoral anteversion and functional balance and postural control in children with spastic cerebral palsy. [Subjects and Methods] Twenty children with spastic cerebral palsy (mean age=12.4 ± 4.5) with grosss motor functional classification system levels I, II, and III were recruited for this study. Functional balance was evaluated using the Pediatric Balance Scale, postural control was evaluated using the Trunk Control Measurement Scale, and femoral anteversion was assessed with a handheld goniometer using the great trochanter prominence method. [Results] The results indicated that there was significant correlation between femoral anteversion and Trunk Control Measurement Scale dynamic reaching score. There were no significant correlation between femoral anteversion and the Trunk Control Measurement Scale static sitting balance, Trunk Control Measurement Scale selective movement control, total Trunk Control Measurement Scale and Pediatric Balance Scale results. [Conclusion] Increased femoral anteversion has not correlation with functional balance, static sitting, and selective control of the trunk. Femoral anteversion is related to dynamic reaching activities of the trunk, and this may be the result of excessive internal pelvic rotation. It is important for the health professionals to understand that increased femoral anteversion needs to be corrected because in addition to leading to femoral internal rotation during walking, it also effects dynamic reaching activities of spastic children with cerebral palsy.

Do changes in torsional magnetic resonance imaging reflect improvement in gait after femoral derotation osteotomy in patients with cerebral palsy?

PURPOSE

Femoral derotation osteotomy (FDO) is commonly used to correct internal rotation gait (IRG) in spastic diplegia. The purpose of this study was to investigate whether the extent of intraoperative derotation is reflected in changes in static (clinical ROM and anteversion angle measured on torsional MRI) and dynamic parameters (transverse plane kinematics in three-dimensional gait analysis) after FDO in children with spastic diplegia.

METHODS

In a prospective study, 30 children with spastic diplegia and IRG were treated with FDO as part of a multilevel surgery and were examined pre- and postoperatively clinically, by three-dimensional gait analysis and by torsional MRI according to a standardised protocol.

RESULTS

A correlation (r = 0.317, p = 0.015) between the extent of intraoperative derotation and mean hip rotation in stance as well as the anteversion angle measured on torsional MRI (r = 0.454, p < 0.001) was found. However, no significant correlation was observed between anteversion angle (tMRI) and mean hip rotation in stance, either before or after FDO.

CONCLUSIONS

Significant improvements were found in IRG after FDO, confirming the results of previous studies. There was no correlation between the anteversion measured on MRI and the mean hip rotation in stance in 3D gait analysis before or after FDO. Thus, the data suggest that if the intraoperative extent of derotation is determined only by the anteversion angle, the result will not be better after FDO. It might only help to avoid retroversion and indicate the maximum amount of femoral derotation. In this study the extent of the intraoperative derotation was orientated at the preoperative midpoint of rotation. Based on the small, but significant correlation between the clinical midpoint and the mean hip rotation in stance in the gait analysis, determination of the intraoperative extent of derotation according to the mean hip rotation in stance seems to give the best results.

Coronal plane knee moments improve after correcting external tibial torsion in patients with cerebral palsy

BACKGROUND

External tibial torsion causes an abnormal axis of joint motion relative to the line of progression with resultant abnormal coronal plane knee moments and affects lever arm function of the foot in power generation at the ankle. However, it is unclear whether surgical correction of the tibial torsion corrects the moments and power.

QUESTIONS/PURPOSES

We evaluated whether surgical correction of external tibial torsion in patients with cerebral palsy would correct the abnormal coronal plane knee moments and improve ankle power generation.

METHODS

We studied 22 patients (26 limbs) with cerebral palsy (Gross Motor Function Classification System Level I or II) who underwent distal internal rotation osteotomies for correction of external tibial torsion as part of a multilevel surgical intervention. There were 10 males and 12 females with a mean age at surgery of 14 years (range, 6.8-20.9 years). All patients had pre- and postoperative standardized clinical evaluation and computerized three-dimensional gait analysis. Minimum followup was 9 months (average, 13 months; range, 9-19 months).

RESULTS

On physical examination, the mean (± SD) transmalleolar axis improved from 43° ± 10° preoperatively to 20° ± 7° postoperatively. Mean knee rotation improved kinematically from 40° ± 9° preoperatively to 21° ± 9° postoperatively. Twenty-two of 26 limbs (88%) improved in one or both peaks of the abnormal coronal plane knee moments. Ankle power generation did not change from preoperative (1.6 ± 0.7 W/kg) to postoperative (1.6 W/kg).

CONCLUSIONS

Correction of external tibial torsion in ambulatory patients with cerebral palsy improves the kinematic and kinetic deviations identified by gait analysis.

LEVELS OF EVIDENCE

Level IV, therapeutic series. See Guidelines for Authors for a complete description of levels of evidence.

Transverse plane rotation of the foot and transverse hip and pelvic kinematics in diplegic cerebral palsy

External rotation of the foot associated with mid-foot break is a commonly observed gait abnormality in diplegic CP patients. Previous studies have shown a correlation between equinus and internal hip rotation in hemiplegic patients. This study aimed to determine if there was a correlation between the amount of transverse plane rotation in diplegic CP patients using kinematic data from standardised gait analysis. Lower limb data of 134 ambulant children with diplegic CP was analysed retrospectively determining the maximum change in foot, hip and pelvis rotation during loading response. Highly significant negative correlations (P=<0.001) were found between foot and hip movements and foot and pelvic movements. Equinus at initial contact diminished the foot:hip correlation while it enhanced the foot:pelvic correlation. There was less external rotation of the foot in equinus patients (P=0.012) and more external rotation of the pelvis in the equinus group (P=<0.001). This data reveal a correlation between transverse plane rotation at foot level to that at the hip and pelvis. The likely biomechanical explanation is relatively excessive transverse external rotation of the foot due to abnormalities such as mid-foot break. When under load, where the foot is fixed to the floor, internal rotation of the entire leg occurs. This is due to lever arm disease as a result of the relatively shortened foot and inefficiency of the plantar-flexion knee-extension couple. Equinus modulates the effect. When treating such patients, lever arm deformities at all levels must be considered to result in the best outcome and prevent recurrences.

New clinical and research trends in lower extremity management for ambulatory children with cerebral palsy

Cerebral palsy (CP) is the most prevalent physical disability in childhood and includes a group of disorders with varying manifestations. This article focuses on current and future intervention strategies for improving mobility and participation during the lifespan for ambulatory children with CP. The provision and integration of physical therapy and medical and orthopedic surgery management focused primarily on the lower extremities are discussed here. Some of the newer trends are more intense and task-related exercise strategies, greater precision in tone identification and management, and a shift towards musculoskeletal surgery that focuses more on promoting dynamic bony alignment and less on releasing or lengthening tendons. Advances in basic and clinical science and technology development are changing existing paradigms and offering renewed hope for improved functioning for children with CP who face a lifelong disability with unique challenges at each stage in life.

Residual pelvic rotation after single-event multilevel surgery in spastic hemiplegia

Our aim in this retrospective study of 52 children with spastic hemiplegia was to determine the factors which affected the amount of residual pelvic rotation after single-event multilevel surgery. The patients were divided into two groups, those who had undergone femoral derotation osteotomy and those who had not. Pelvic rotation improved significantly after surgery in the femoral osteotomy group (p < 0.001) but not in the non-femoral osteotomy group. Multiple regressions identified the following three independent variables, which significantly affected residual pelvic rotation: the performance of femoral derotation osteotomy (p = 0.049), the pre-operative pelvic rotation (p = 0.003) and the post-operative internal rotation of the hip (p = 0.001). We concluded that there is a decrease in the amount of pelvic rotation after single-event multilevel surgery with femoral derotation osteotomy. However, some residual rotation may persist when patients have severe rotation before surgery.

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.

Influence of thigh cluster configuration on the estimation of hip axial rotation

The non-invasive estimation of hip axial rotation is prone to error. Most of this is likely to originate from soft tissue artefact (STA) at the thigh. The purpose of this study was to evaluate the relative performance of four different thigh cluster configurations. Three were novel configurations whilst one represented the Helen Hayes convention. Twenty able-bodied adults performed two alternative motor tasks involving hip axial rotation: gait and an isolated longitudinal rotation task. Kinematic data were acquired using a three-dimensional motion analysis system (VICON 512, Oxford Metrics, Oxford, England). Indirect criteria were used to evaluate STA. Hip axial rotation kinematic profiles during gait were highly sensitive to thigh cluster configuration. For the longitudinal rotation task, the various thigh clusters were only capable of estimating, at best, up to 60% of the reference amount of movement. The Helen Hayes convention was associated with the greatest degree of STA. Whilst none of the clusters represented an optimal solution, a non-rigid configuration on the distal thigh provided a more favourable alternative. The main limitation associated with this study was the absence of a true gold standard measure of hip axial rotation. Until future work provides further insight, one must remain cautious when using estimates of hip axial rotation for purposes of research or clinical interpretation.

Internal rotation gait in spastic diplegia--critical considerations for the femoral derotation osteotomy

The purpose of this study was to assess under- and overcorrection following femoral derotation osteotomy (FDO) in spastic diplegic children with functionally compromising internally rotated gait, especially with respect to asymmetry. A total of 30 children with spastic diplegia and internally rotated gait underwent multilevel surgery including FDO and were assessed pre- and 1 year postoperatively by clinical examination and instrumented gait analysis. The amount of derotation was determined intra-operatively based on the neutral midpoint between passive internal and external hip rotation and was controlled with K-wires. Sixteen patients showed an asymmetry in mean hip rotation in stance of more than 10 degrees preoperatively. Accordingly, all legs were classified as the more or the less involved side. Improvement parameters were established for the evaluation of over- and undercorrection. For the clinical midpoint, no significant difference in change and improvement was found between the sides. The mean hip rotation in stance improved significantly in the more involved side with few incidences of mal-correction (13%). The less involved side, however, got worse due to a high occurrence of over- and undercorrections (59%). Hence the clinical midpoint as indication criterion does not give sufficient information about the functional alignment of the distal femur during gait, especially in legs with mild involvement. The study underlines the importance of gait analysis for indication in addition to the clinical midpoint. Taking into account the precision of gait analysis data and derotation amount, we suggest FDO to be carried out if the mean internal hip rotation in stance exceeds 15 degrees .

Gait classification in children with cerebral palsy: a systematic review

This systematic review of the literature evaluates the validity of existing classifications of gait deviations in children with cerebral palsy (CP). Numerous efforts have been made to develop classification systems for gait in CP to assist in diagnosis, clinical decision-making and communication. The internal and external validity of gait classifications in 18 studies were examined, including their sampling methods, content validity, construct validity, reliability and clinical utility. Half of the studies used qualitative pattern recognition to construct the gait classification and the remainder used statistical techniques such as cluster analysis. Few adequately defined their samples or sampling methods. Most classifications were constructed using only sagittal plane gait data. Many did not provide adequate guidelines or evidence of reliability and validity of the classification system. No single classification addressed the full magnitude or range of gait deviations in children with CP. Although gait classification in CP can be useful in clinical and research settings, the methodological limitations of many classifications restrict their clinical and research applicability.

Soft tissue surgery for equinus deformity in spastic hemiplegic cerebral palsy: effects on kinematic and kinetic parameters

The purpose of this study was to evaluate how soft tissue surgery for correcting equinus deformity affects the kinematic and kinetic parameters of the ankle and proximal joints. Sixteen children with spastic hemiplegic cerebral palsy and equinus deformities (age range 3-16 years) were included. Soft tissue surgeries were performed exclusively on the ankle joint area in all subjects. Using computerized gait analysis (Vicon 370 Motion Analysis System), the kinematic and kinetic parameters during barefoot ambulation were collected preoperatively and postoperatively. In all 16 children, the abnormally increased ankle plantar flexion and pelvis anterior tilting on the sagittal plane were significantly improved without a weakening of push-off (p < 0.05). In a group of 8 subjects with a recurvatum knee gait pattern before operation, the postoperative kinematic and kinetic parameters of the knee joint were significantly improved (p < 0.05). In a group of 8 subjects with ipsilateral pelvic external rotation before operation, the postoperative pelvic deviations on the transverse plane were significantly decreased (p < 0.05). These findings suggest that the soft tissue surgery for correcting equinus deformity improves not only the abnormal gait pattern of the ankle, but also that of the knee and pelvis.

Multilevel orthopaedic surgery in group IV spastic hemiplegia

Most children with spastic hemiplegia have high levels of function and independence but fixed deformities and gait abnormalities are common. The classification proposed by Winters et al is widely used to interpret hemiplegic gait patterns and plan intervention. However, this classification is based on sagittal kinematics and fails to consider important abnormalities in the transverse plane. Using three-dimensional gait analysis, we studied the incidence of transverse-plane deformity and gait abnormality in 17 children with group IV hemiplegia according to Winters et al before and after multilevel orthopaedic surgery. We found that internal rotation of the hip and pelvic retraction were consistent abnormalities of gait in group-IV hemiplegia. A programme of multilevel surgery resulted in predictable improvement in gait and posture, including pelvic retraction. In group IV hemiplegia pelvic retraction appeared in part to be a compensating mechanism to control foot progression in the presence of medial femoral torsion. Correction of this torsion can improve gait symmetry and function.