Collagen architecture and biomechanics of gracilis and adductor longus muscles from children with cerebral palsy.

Cerebral palsy (CP) describes some upper motoneuron disorders due to non-progressive disturbances occurring in the developing brain that cause progressive changes to muscle. While longer sarcomeres increase muscle stiffness in patients with CP compared to typically developing (TD) patients, changes in extracellular matrix (ECM) architecture can increase stiffness. Our goal was to investigate how changes in muscle and ECM architecture impact muscle stiffness, gait and joint function in CP. Gracilis and adductor longus biopsies were collected from children with CP undergoing tendon lengthening surgery for hamstring and hip adduction contractures, respectively. Gracilis biopsies were collected from TD patients undergoing anterior cruciate ligament reconstruction surgery with hamstring autograft. Muscle mechanical testing, two-photon imaging and hydroxyproline assay were performed on biopsies. Corresponding data were compared to radiographic hip displacement in CP adductors (CPA), gait kinematics in CP hamstrings (CPH), and joint range of motion in CPA and CPH. We found at matched sarcomere lengths muscle stiffness and collagen architecture were similar between TD and CP hamstrings. However, CPH stiffness (R2 = 0.1973), collagen content (R2 = 0.5099) and cross-linking (R2 = 0.3233) were correlated to decreased knee range of motion. Additionally, we observed collagen fibres within the muscle ECM increase alignment during muscular stretching. These data demonstrate that while ECM architecture is similar between TD and CP hamstrings, collagen fibres biomechanics are sensitive to muscle strain and may be altered at longer in vivo sarcomere lengths in CP muscle. Future studies could evaluate the impact of ECM architecture on TD and CP muscle stiffness across in vivo operating ranges. KEY POINTS: At matched sarcomere lengths, gracilis muscle mechanics and collagen architecture are similar in TD patients and patients with CP. In both TD and CP muscles, collagen fibres dynamically increase their alignment during muscle stretching. Aspects of muscle mechanics and collagen architecture are predictive of in vivo knee joint motion and radiographic hip displacement in patients with CP. Longer sarcomere lengths in CP muscle in vivo may alter collagen architecture and biomechanics to drive deficits in joint mobility and gait function.

Creating an autoencoder single summary metric to assess gait quality to compare surgical outcomes in children with cerebral palsy: The Shriners Gait Index (SGI).

Gait for individuals with movement disorders varies widely and the variability makes it difficult to assess outcomes of surgical and therapeutic interventions. Although specific joints can be assessed by fewer individual measures, gait depends on multiple parameters making an overall assessment metric difficult to determine. A holistic, summary measure can permit a standard comparison of progress throughout treatments and interventions, and permit more straightforward comparison across varied subjects. We propose a single summary metric (the Shriners Gait Index (SGI)) to represent the quality of gait using a deep learning autoencoder model, which helps to capture the nonlinear statistical relationships among a number of disparate gait metrics. We utilized gait data of 412 individuals under the age of 18 collected from the Motion Analysis Center (MAC) at the Shriners Children's - Chicago. The gait data includes a total of 114 features: temporo-spatial parameters (7), lower extremity kinematics (64), and lower extremity kinetics (43) which were min-max normalized. The developed SGI score captured more than 89% variance of all 144 features using subject-wise cross-validation. Such summary metrics holistically quantify an individual's gait which can then be used to assess the impact of therapeutic interventions. The machine learning approach utilized can be leveraged to create such metrics in a variety of contexts depending on the data available. We also utilized the SGI to compare overall changes to gait after surgery with the goal of improving mobility for individuals with gait disabilities such as Cerebral Palsy.

HipScreen mobile app for the measurement of hip migration percentage in children with cerebral palsy: Accuracy, reliability, and discriminatory ability.

AIM: To assess the accuracy, reliability, and discriminatory ability of a mobile app for measurement of migration percentage in hip surveillance radiographs of children with cerebral palsy (CP). METHOD: The free mobile app HipScreen (www.hipscreen.org) was utilized by a diverse group of users to measure the migration percentage of 40 hips at two time points after completing an online tutorial and competency test. The mean absolute error (MAE) was calculated against the reference standard obtained on a radiology workstation. Statistical analyses included linear regression, intraclass correlation coefficient (ICC), and area under receiver-operating characteristic curve (AUC). RESULTS: Thirty-seven users completed the study, with 30 having a healthcare professional background, but only 15 with x-ray interpretation expertise. The overall MAE of migration percentage measurement using the HipScreen app was 5.72% (95% confidence interval [CI]: 5.38-6.06), with good reliability between time points (ICC = 0.83). With a migration percentage less than 30% considered as a positive case, the HipScreen app had a sensitivity of 94% (95% CI: 87-97), specificity of 66% (95% CI: 61-77), and an AUC of 0.92 (95% CI: 0.88-0.96). INTERPRETATION: Users from a broad range of backgrounds can utilize the HipScreen app to measure hip surveillance radiographs with clinically acceptable accuracy, reliability, and discriminatory ability. WHAT THIS PAPER ADDS: The HipScreen app can accurately and reliably measure migration percentage. As a screening tool, HipScreen has excellent sensitivity and discriminatory ability. A broad range of HipScreen users achieve clinically acceptable performance.

Surgical Management of Severe Equinus Deformity in Ambulatory Children With Cerebral Palsy.

BACKGROUND: Tendo Achilles lengthening (TAL) for the management of equinus contractures in ambulatory children with cerebral palsy (CP) is generally not recommended due to concerns of over-lengthening, resulting in weakness and plantar flexor insufficiency. However, in some cases, surgical correction of severe equinus deformities can only be achieved by TAL. The goal of this study is to assess the outcomes following TAL in these cases. METHODS: A retrospective cohort study of children with CP with severe equinus contractures (ankle dorsiflexion with the knee extended of -20 degrees or worse) who underwent TAL as part of a single event multilevel surgery, with preoperative and postoperative gait analysis studies. Continuous data were analyzed by paired t test, and categorical data by McNemar Test. RESULTS: There were 60 subjects: 42 unilateral, 18 bilateral CP; 41 GMFCS II, 17 GMFCS I; mean age at surgery was 10.6 years, mean follow-up was 1.3 years. Ankle dorsiflexion with the knee extended improved from -28 to 5 degrees (P<0.001). The ankle Gait Variable Score improved from 34.4 to 8.6 (P<0.001). The ankle moment in terminal stance improved from 0.43 to 0.97 Nm/kg (P<0.001). Significant improvements (P<0.001) were seen in radiographic measures of foot alignment following surgery. There were few significant differences in the outcome parameters between subjects with unilateral versus bilateral CP (eg, only the bilateral group showed improved but persistent increased knee flexion in mid-stance). CONCLUSIONS: The outcomes following TAL for the management of severe equinus deformity in ambulatory children with CP were favorable 1 year after surgery, with significant improvements in all domains measured. SIGNIFICANCE: This study does not advocate for the widespread use of TAL to correct equinus deformity in children with CP. However, it does show that good short-term outcomes following TAL are possible in properly selected subjects with severe contractures when the dosing of the surgery is optimal (correction of contracture to between 0 and 5 degrees of dorsiflexion with the knee extended) and the procedure is performed in the setting of single event multilevel surgery with subsequent proper orthotic management and rehabilitation.

Finding consensus for hamstring surgery in ambulatory children with cerebral palsy using the Delphi method.

Purpose: There is marked variation in indications and techniques for hamstring surgery in children with cerebral palsy. There is particular uncertainty regarding the indications for hamstring transfer compared to traditional hamstring lengthening. The purpose of this study was for an international panel of experts to use the Delphi method to establish consensus indications for hamstring surgery in ambulatory children with cerebral palsy. Methods: The panel used a five-level Likert-type scale to record agreement or disagreement with statements regarding hamstring surgery, including surgical indications and techniques, post-operative care, and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert-type ratings. General agreement was defined as 60%-79% falling into the highest or lowest two ratings. There was no agreement if neither of these thresholds was reached. Results: The panel reached consensus or general agreement for 38 (84%) of 45 statements regarding hamstring surgery. The panel noted the importance of assessing pelvic tilt during gait when considering hamstring surgery, and also that lateral hamstring lengthening is rarely needed, particularly at the index surgery. They noted that repeat hamstring lengthening often has poor outcomes. The panel was divided regarding hamstring transfer surgery, with only half performing such surgery. Conclusion: The results of this study can help pediatric orthopedic surgeons optimize decision-making in their choice and practice of hamstring surgery for ambulatory children with cerebral palsy. This has the potential to reduce practice variation and significantly improve outcomes for ambulatory children with cerebral palsy. Level of evidence: level V.

Anterior distal femoral hemiepiphysiodesis in children with cerebral palsy: Establishing surgical indications and techniques using the modified Delphi method and literature review.

Purpose: The purpose of this study was to develop consensus for the surgical indications of anterior distal femur hemiepiphysiodesis in children with cerebral palsy using expert surgeon opinion through a modified Delphi technique. Methods: The panel used a 5-level Likert-type scale to record agreement or disagreement with 27 statements regarding anterior distal femur hemiepiphysiodesis. Consensus was defined as at least 80% of responses being in the highest or lowest 2 of the Likert-type ratings. General agreement was defined as 60%-79% falling into the highest or lowest 2 ratings. Results: For anterior distal femur hemiepiphysiodesis, 27 statements were surveyed: consensus or general agreement among the panelists was achieved for 22 of 27 statements (22/27, 82%) and 5 statements had no agreement (5/27, 18%). There was general consensus that anterior distal femur hemiepiphysiodesis is indicated for ambulatory children with cerebral palsy, with at least 2 years growth remaining, and smaller (<30 degrees) knee flexion contractures and for minimally ambulatory children to aid in standing/transfers. Consensus was achieved regarding the importance of close radiographic follow-up after screw insertion to identify or prevent secondary deformity. There was general agreement that percutaneous screws are preferred over anterior plates due to the pain and irritation associated with plates. Finally, it was agreed that anterior distal femur hemiepiphysiodesis was not indicated in the absence of a knee flexion contracture. Conclusion: Anterior distal femur hemiepiphysiodesis can be used to treat fixed knee flexion contractures in the setting of crouch gait, but other associated lever arm dysfunctions must be addressed by single-event multilevel surgery. Level of evidence: V.

Neuraxial anesthesia for post-operative pain control after hip surgery in children with cerebral palsy and pre-existing intrathecal baclofen pumps.

PURPOSE: The purpose of this study is to describe the efficacy and adverse events of neuraxial anesthesia for post-operative pain control in non-ambulatory children with cerebral palsy with pre-existing intrathecal baclofen (ITB) pumps undergoing hip reconstructive or palliative surgery. METHODS: Twelve children (mean age 11.25 years) were included in the study with the following neuraxial anesthesia methods: indwelling epidural catheter (8 patients), neuraxial opioids administered through the side port of the ITB pump (3 patients), and single injection spinal anesthetic (1 patient). Observational pain scores and opioid requirements were quantified for all patients. RESULTS: There were no ITB pump or surgical complications at a mean follow-up of 2.2 years. The average length of stay was 6 days. Patients had good post-operative pain control with a mean observational pain score of 0.7 and mean morphine equivalent use of 0.26mg/kg/day. Four patients required anti-emetics to control nausea and three patients had urinary retention requiring repeat catheterization, but all medical complications resolved prior to discharge. CONCLUSION: Neuraxial anesthesia can effectively control post-operative pain in children with a pre-existing ITB pump. Utilizing the side port of the ITB pump for administration of neuraxial opioids is an option when epidural or spinal anesthesia is not possible.

Distal rectus femoris surgery in children with cerebral palsy: results of a Delphi consensus project.

PURPOSE: The purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method. METHODS: The panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached. RESULTS: Consensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade. CONCLUSION: This study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP. LEVEL OF EVIDENCE: V.

Outcomes of Patellar Tendon Imbrication With Distal Femoral Extension Osteotomy for Treatment of Crouch Gait.

BACKGROUND: Crouch gait is a frequent gait abnormality observed in children with cerebral palsy. Distal femoral extension osteotomy (DFEO) with the tightening of the extensor mechanism is a common treatment strategy to address the pathologic knee flexion contracture and patella alta. The goal of this study was to review the results of a patellar tendon imbrication (PTI) strategy to address quadriceps insufficiency in the setting of children undergoing DFEO. METHODS: After institutional review board approval, all patients with crouch gait treated at a single institution with DFEO and PTI were identified. Clinical, radiographic, and instrumented gait analysis data were analyzed preoperatively and at 1 year following surgery. RESULTS: Twenty-eight patients (54 extremities) with a diagnosis of cerebral palsy and crouch gait were included. Significant improvements were appreciated in the degree of knee flexion contracture, quadriceps strength, knee extensor lag, and popliteal angle (P<0.01). Knee flexion at initial contact and during mid-stance improved significantly (P<0.0001), and knee moments in late stance were significantly reduced (P<0.01). The anterior pelvic tilt, however, significantly increased postoperatively (P<0.0001). Radiographic improvements were seen in the knee flexion angle and patellar station as assessed by the Koshino Sugimoto Index (P<0.0001). Four patients (14.2%) developed a recurrence of knee flexion contracture requiring further intervention. CONCLUSIONS: PTI is a simplified and safe technique to address quadriceps insufficiency when performing DFEO. The short-term results of patients who underwent DFEO with PTI demonstrated improvements in clinical, radiographic, and gait analysis variables of the knee. Investigating long-term outcomes, comparing techniques, and assessing quality of life measures are important next steps in research. LEVEL OF EVIDENCE: Level IV-case series.

Surgical Outcomes for Severe Idiopathic Toe Walkers.

BACKGROUND: Idiopathic toe walking (ITW) is a diagnosis of exclusion and represents a spectrum of severity. Treatment for ITW includes observation and a variety of conservative treatment methods, with surgical intervention often reserved for severe cases. Previous studies reviewing treatment outcomes are often difficult to interpret secondary to a mixture of case severity. The goal of this study was to review surgical outcomes in patients with severe ITW who had failed prior conservative treatment, as well as determine differences in outcomes based on the type of surgery performed. METHODS: After IRB approval, all patients with surgical management of severe ITW at a single institution were identified. Zone II or zone III plantar flexor lengthenings were performed in all subjects. Clinical, radiographic, and motion analysis data were collected preoperatively and at 1 year following surgery. RESULTS: Twenty-six patients (46 extremities) with a diagnosis of severe ITW from 2002 to 2017 were included. Zone II lengthenings were performed in 25 extremities (mean age=9.9 y) and zone III lengthenings were performed in 21 extremities (mean age=8.6 y). At the most recent follow-up, 100% of zone III lengthening extremities and 88% of zone II lengthening demonstrated decreased severity of ITW. Six extremities required additional treatment, all of which were initially managed with zone II lengthenings. CONCLUSIONS: Severe ITW or ITW that has not responded to conservative treatment may benefit from surgical intervention. More successful outcomes, including continued resolution of toe walking, were observed in subjects treated with zone III lengthenings. LEVEL OF EVIDENCE: Level III-case series.

Indications for gastrocsoleus lengthening in ambulatory children with cerebral palsy: a Delphi consensus study.

PURPOSE: Equinus is the most common deformity in cerebral palsy (CP) and gastrocsoleus lengthening (GSL) is the most commonly performed surgery to improve gait and function in ambulatory children with CP. Substantial variation exists in the indications for GSL and surgical technique. The purpose of this study was to review surgical anatomy and biomechanics of the gastrocsoleus and to utilize expert orthopaedic opinion through a Delphi technique to establish consensus for surgical indications for GSL in ambulatory children with CP. METHODS: A 17-member panel, of Fellowship-trained paediatric orthopaedic surgeons, each with at least 9 years of clinical post-training experience in the surgical management of children with CP, was established. Consensus for the surgical indications for GSL was achieved through a standardized, iterative Delphi process. RESULTS: Consensus was reached to support conservative Zone 1 surgery in diplegia and Zone 3 surgery (lengthening of the Achilles tendon) was contraindicated. Zone 2 or Zone 3 surgery reached general agreement as a choice in hemiplegia and under-correction was preferred to any degree of overcorrection. Agreement was reached that the optimum age for GSL surgery was 6 years to 10 years and should be avoided in children aged under 4 years. Physical examination measures with the child awake and under anaesthesia were important in decision making. Gait analysis was supported both for decision making and for assessing outcomes, in combination with patient reported outcomes (PROMS). CONCLUSIONS: The results from this study may encourage informed practice evaluation, reduce practice variability, improve clinical outcomes and point to questions for further research. LEVEL OF EVIDENCE: V.

Establishing surgical indications for hamstring lengthening and femoral derotational osteotomy in ambulatory children with cerebral palsy.

PURPOSE: Surgical procedures, such as medial hamstring lengthening (MHL) and femoral derotational osteotomy (FDO), can improve the gait of children with cerebral palsy (CP); however, substantial variation exists in the factors that influence the decision to perform surgery. The purpose of this study was to use expert surgeon opinion through a Delphi technique to establish consensus for indications in ambulatory children with CP. METHODS: A 15-member panel, all established experts with at least nine years' experience in the surgical management of children with CP, was created (mean of 20.81 years' experience). All panel members also had expertise of the use of movement analysis for the assessment of gait disorders in children with CP. The group initially focused on two of the most commonly performed procedures, MHL and FDO, in an attempt to gain consensus (> 80%). This was obtained through a standardized, iterative Delphi process. RESULTS: For MHL, a total of 59 questions were surveyed: 41 indication questions and 18 outcome questions, for which there was consensus on ten indication questions and seven outcomes. For FDO, a total of 55 questions were surveyed: 43 indication questions and 12 outcome questions, for which there was consensus on 29 indication questions and eight outcomes. CONCLUSION: This study is the first to use an expert panel to identify best-practice indications for common surgical procedures of children with CP. The results from this study will allow for more informed evaluation of practice and form the basis for future improvement efforts to standardize surgical recommendations internationally. LEVEL OF EVIDENCE: Level IV.

Brazilian version of the shriners hospital upper extremity evaluation (shuee): translation, cultural adaptation, and evaluation of psychometric properties / Versão brasileira do shriners hospital upper extremity evaluation: tradução, adaptação cultural e validação das propriedades psicométricas

ABSTRACT Objective: To validate the upper limb assessments tool, Shriners Hospital Upper Extremity Evaluation (SHUEE), for individuals with hemiplegic cerebral palsy in the Brazilian population. Methods: Validation study to translate and culturally adapt the Manual and the instrument. The psychometric properties evaluated were reliability and convergent validity. Reliability was determined by internal consistency (Cronbach's α coefficient), ceiling and floor effect, sensitivity to changes, and intra- and interobserver agreement. Convergent validity was performed using the Pediatric Motor Activity Log, the self-care scale of the Pediatric Evaluation of Disability Inventory, and the Manual Ability Classification System. Results: We evaluated 21 individuals with hemiplegic cerebral palsy, with a mean age of 8.7±4.0 years. After the instrument was translated, there was no need for cultural adaptation. The total Cronbach's α coefficient was 0.887 (95% confidence interval [95%CI] 0.745-0.970). We calculated sensitivity to changes in five subjects who underwent treatment with Botulinum Toxin Type A and physical therapy, with a significant difference between pre- and post-treatment evaluations in the Spontaneous Functional Analysis and Dynamic Positional Analysis. Convergent validity showed a significant correlation of the Spontaneous Functional Analysis and Dynamic Positional Analysis with the scales evaluated. All items of SHUEE presented high intra- and interobserver agreement. Conclusions: The results revealed that the Brazilian version of the SHUEE demonstrated good reliability and convergent validity, suggesting that it is an adequate and reliable tool for individuals with hemiplegic cerebral palsy in the Brazilian population.

RESUMO Objetivo: Validar o instrumento de avaliação do membro superior, Shriners Hospital Upper Extremity Evaluation (SHUEE), para indivíduos com paralisia cerebral hemiplégica da população brasileira. Métodos: Estudo de validação no qual foi realizada tradução e adaptação cultural do manual e do instrumento. As propriedades psicométricas avaliadas foram confiabilidade e validade convergente. A confiabilidade foi determinada através da consistência interna (coeficiente α de Cronbach), efeito teto e chão, sensibilidade à mudança e concordância intra e interobservador. A validade convergente foi realizada utilizando-se o Pediatric Motor Activity Log, a escala de autocuidados do Pediatric Evaluation of Disability Inventory e o Manual Ability Classification System. Resultados: Foram avaliados 21 indivíduos com paralisia cerebral hemiplégica com idade média de 8,7±4,0 anos. Após a tradução do instrumento, não houve necessidade de adaptação cultural. O coeficiente α de Cronbach total foi de 0,887 (intervalo de confiança de 95% [IC95%] 0,745-0,970). A sensibilidade à mudança foi calculada em cinco indivíduos que realizaram aplicação de Toxina Botulínica tipo A e fisioterapia, apresentando diferença significativa entre a avaliação pré e pós-tratamento na Análise Funcional Espontânea e Análise Posicional Dinâmica. A validade convergente mostrou correlação significativa da Análise Funcional Espontânea e Análise Posicional Dinâmica com as escalas avaliadas. Todos os itens do SHUEE apresentaram concordâncias fortes, tanto na avaliação intra quanto na interobservador. Conclusões: A versão brasileira do SHUEE demonstrou um bom desempenho em relação à confiabilidade e validade convergente, sugerindo ser uma ferramenta adequada e confiável para os indivíduos com paralisia cerebral hemiplégica na população brasileira.

Guided Growth of the Proximal Femur for the Management of Hip Dysplasia in Children With Cerebral Palsy.

BACKGROUND: Progressive hip displacement is one of the most common and debilitating deformities seen in children with cerebral palsy (CP). The aim of this study was to evaluate the results of temporary medial hemiepiphysiodesis of the proximal femur (TMH-PF) using a transphyseal screw to control hip migration during growth in children with CP. METHODS: This was a retrospective study of children with CP and hip dysplasia, age 4 to 11 years and GMFCS levels III-V. There were 28 patients with 56 hips that underwent TMH-PF surgery between 2007 and 2010. Clinical and radiologic evaluation was performed preoperatively, at 6, 12, and 60 months following the index surgery. Acetabular index (AI), neck-shaft angle (NSA) and migration percentage (MP) were measured. All complications were recorded. RESULTS: All radiographic measurements were significantly improved at the final follow-up. Positive correlations were found between NSA, MP, and AI. Multiple regression analysis revealed that MP, time from surgery, and age were influenced by the decrease of the NSA. The femoral physis grew off the screw in 9 hips within 36 months. The screw head broke during attempted screw exchange in 1 hip. The remain cases (4 hips) were treated by placing a second screw parallel to the existing one. Finally, progressive subluxation occurred in 3 hips when the physis grew off the screw and were treated by skeletal reconstruction. CONCLUSIONS: TMH-PF was effective in controlling progressive subluxation of the hip in the majority of cases, obviating the need for major reconstructive surgery in these children with CP. LEVEL OF EVIDENCE: Level IV.

Quantitative Assessment of Muscle Strength Following "Slow" Surgical Lengthening of the Medial Hamstring Muscles in Children With Cerebral Palsy.

BACKGROUND: Classic teaching for surgical lengthening of muscle contractures in children with cerebral palsy (CP) has emphasized complete correction of the deformity acutely, with immobilization of the targeted muscles in the fully corrected position. Clinical experience has led to the impression that the muscles are invariably weakened by this approach. We have developed an alternative technique for correction of contractures called slow surgical lengthening (SSL). The goal of the study was to determine the physical examination, kinematic, and muscle strength outcomes following SSL of the medial hamstring muscles in children with CP. METHODS: The study group included 41 children with CP who underwent SSL of the medial hamstring muscles as part of a comprehensive single-event multilevel surgery, who had preoperative and 1-year postoperative evaluations in our Motion Analysis Center, which included quantitative assessment of isometric and isokinetic muscle strength. RESULTS: All subjects were Gross Motor Function Classification System I and II. Mean age at the time of surgery was 10.8 years. The mean popliteal angle improved by 16.2 degrees (P<0.001) following SSL of the medial hamstrings. Sagittal plane kinematics following SSL of the medial hamstrings showed improvement of knee extension at initial contact of 10.2 degrees (P<0.001), decrease of peak knee flexion in mid-swing of 3.6 degrees (P=0.014), improved minimum knee flexion in stance of 4.9 degrees (P=0.002), and no significant change in mean anterior pelvic tilt (P=0.123). Mean peak isometric knee flexion torque remained unchanged from preoperative to postoperative studies (P=0.154), whereas mean peak isokinetic knee flexion torque significantly increased by 0.076 Nm/kg (P=0.014) following medial hamstring SSL. DISCUSSION: SSL was developed based upon clinical experience and improved understanding of the pathophysiology of skeletal muscle in children with CP. The SSL technique allows the tendinous tissue to separate spontaneously at the time of recession, but does not force further acute lengthening by intraoperative manipulation, thereby minimizing the damage to the underlying muscle. It is broadly believed that muscle weakness is inevitable following surgical lengthening. The current study shows that the SSL technique does not cause weakness. LEVEL OF EVIDENCE: Level IV-therapeutic.

Outcomes of Preoperative Versus Postoperative Radiation for Heterotopic Ossification Prevention in Children With Neuromuscular Hip Dysplasia Undergoing Proximal Femoral Resection.

BACKGROUND: Few studies exist to inform the extrapolated practice of irradiating children for heterotopic ossification (HO) prevention. We report the incidence of HO formation following prophylactic preoperative compared with postoperative radiation therapy (RT) in children with neuromuscular hip dysplasia (NHD) following proximal femoral resection (PFR). METHODS: A retrospective, 2-institution chart review was performed. Eligibility was limited to patients with at least 1 year of follow-up. Evaluation included radiographic HO grading by a combined severity scale, assessment of synchronous symptoms of pain or decreased range of motion, and stratification by preoperative versus postoperative reception of RT. A control cohort included 4 nonirradiated hips with NHD after PFR. RESULTS: Twenty-five hips in 20 children met eligibility criteria. Eleven hips were irradiated preoperatively and 14 postoperatively. Radiographic evidence of post-RT development of radiographic evidence of heterotopic ossification (rHO) was found in all 25 hips and earlier in patients irradiated preoperatively (median time to rHO was 4.0 vs. 15.7 mo, P=0.03, 95% confidence interval, 0.24-21.5). There was no statistically significant difference in the development of symptomatic HO (P=0.62) between the preoperative (45.5%) and postoperative (35.7%) groups, nor in HO grade (P=0.34). Seven (28%) of the 25 hips (5 preoperative and 2 postoperative) had documentation of rHO-free intervals after surgery, with an average duration of 5.6 months, while the remaining presented with rHO at first follow-up visit. All eligible control hips (100%) developed rHO and symptomatic heterotopic ossification. CONCLUSIONS: Perioperative RT did not prevent the formation of HO in any child with NHD after PFR. Extrapolation of evidence of the efficacy of RT for HO prevention in ambulatory adults after traumatic hip injury to a population of children with central nervous system injury and NHD may be premature. Additional studies are needed to clarify optimal prevention of HO in this population. LEVEL OF EVIDENCE: Level III-therapeutic retrospective comparative study.

Management of Neuromuscular Hip Dysplasia in Children With Cerebral Palsy: Lessons and Challenges.

Optimal clinical decision making and surgical management of hip dysplasia in children with cerebral palsy (CP) requires an understanding of the underlying pathophysiology (pathomechanics and pathoanatomy), incidence, and natural history. The incidence of hip dysplasia in children with CP is directly related to the degree of motor impairment. A subluxated or dislocated hip in a child with CP can compromise the quality of life for both the child and their caregivers. The goal of this article is to highlight the events over the last 25 years that have had the greatest impact on the management of hip dysplasia in children with CP. It is my opinion that the 2 most significant advances during this time have been the development of a classification system based upon motor impairment (the Gross Motor Function Classification System), and the development of surveillance programs for hip dysplasia in children with CP. This article will contrast neuromuscular hip dysplasia with developmental dysplasia of the hip. It will be shown how the development and utilization of the Gross Motor Function Classification System has contributed to our understanding of the epidemiology and natural history of hip dysplasia in children with CP, and to the assessment of outcomes following surgical management. The impact of hip surveillance programs on early soft tissue surgeries, skeletal hip reconstructions, and the incidence of hip dislocations and salvage surgeries will be reviewed. Challenges in the implementation of hip surveillance programs in resource poor and decentralized health care delivery systems will be considered, and innovative approaches identified.

Correlation Between Standard Upper Extremity Impairment Measures and Activity-based Function Testing in Upper Extremity Cerebral Palsy.

BACKGROUND: Although the treatment of cerebral palsy should be based on improving function as assessed by measures of impairment, activity, and participation, the standard indications for surgical treatment of upper extremity cerebral palsy (UECP) are impairment measures, primarily active and passive range of motion (ROM). Recently, validated activity measures have been developed for children with UECP. The purposes of this study were to determine the relationship between impairment and activity measures in this population, and whether measures of activity correlate with each other. METHODS: A total of 37 children, ages 5 to 16 years, who met standard ROM surgical indications for UECP were evaluated with the impairment measures of active and passive ROM and stereognosis, as well as 3 activity measures [Assisting Hand Assessment (AHA), Box and Blocks test, and the Shriners Hospitals Upper Extremity Evaluation Dynamic Positional Analyses (SHUEE DPA)]. Impairment measures were correlated with activity measures using Spearman rank correlation coefficients. RESULTS: Impairment measures showed inconsistent correlation with activity measures. Of the 12 comparisons, only 4 correlated: active forearm supination (ρ=0.47, P=0.003), wrist extension (ρ=0.55, P=0.001), and stereognosis scores (ρ=0.54, P=0.001) were correlated with AHA; and wrist extension was correlated with the SHUEE DPA (ρ=0.41, P=0.01). When the results of activity tests were compared, the AHA was correlated with the Box and Blocks tests (ρ=0.63, P<0.001), and the SHUEE DPA and Box and Blocks tests were correlated with each other (ρ=0.35, P=0.04). CONCLUSIONS: The goal of surgery in UECP is to improve the child's ability to perform activities, and ultimately to participate in life situations. Impairment measures, such as ROM, were inconsistently correlated with validated measures of activity. Some activity measures correlated with each other, although they did not correlate with the same impairment measures. We conclude that impairment measures, including ROM, do not consistently predict functional dynamic ROM used to perform activities for children with UECP. Activity limitation measures may provide more appropriate indicators than impairment measures for upper extremity surgery for this population. LEVEL OF EVIDENCE: Level II-diagnostic.

Outcomes of Cutaneous Scar Revision During Surgical Implant Removal in Children with Cerebral Palsy.

BACKGROUND: Children who have had surgery involving the placement of an implant frequently undergo a subsequent surgery for hardware removal. The cosmesis of surgical scars following initial and subsequent surgeries is unpredictable. Scar incision (subsequent surgical incision through the initial scar) or excision (around the initial scar) is selected on the basis of the quality of the initial scar. The outcomes following these techniques have not been determined. METHODS: This prospective, consecutive case series was designed to compare outcomes following surgical scar incision versus excision at the time of implant removal in children with cerebral palsy. Photographs of the scars were made preoperatively and at 6 and 12 months following implant removal and were graded for scar quality utilizing the modified Stony Brook Scar Evaluation Scale (SBSES). Parental assessment of scar appearance was performed at the same time points utilizing a visual analog cosmetic scale (VACS). RESULTS: The scars that were selected for incision had significantly worse SBSES scores at 6 and 12 months following the second surgery compared with preoperative values. However, parents' VACS scores of the incised scars, although worse at 6 months, were comparable with preoperative scores at 12 months. Scars that were selected for excision had significantly worse SBSES scores at 6 months but scores that were comparable with preoperative values at 12 months. VACS scores for the excised scars were comparable at the 3 time points. CONCLUSIONS: Surgical incisions that initially healed with good scar quality generally healed well (from the parents' perspective) following subsequent incision through the previous scar. Surgical incisions that initially healed with poor scar quality did not heal better following excision of the previous scar. In such situations, surgical excision of the existing scar should occur in conjunction with additional adjuvant therapies to improve cosmesis. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Surgical management of persistent intoeing gait due to increased internal tibial torsion in children.

BACKGROUND: Intoeing gait is frequently seen in developing children, and in most cases it resolves with growth. However, persistent, extreme intoeing gait, due to increased internal tibial torsion, may disrupt gait function. At our institution, children with symptomatic intoeing gait are evaluated per a standardized protocol, which includes quantitative gait analysis. When the primary cause is increased internal tibial torsion, surgical correction by supramalleolar tibial rotational osteotomy is recommended. METHODS: The study design was a retrospective case series, with normative controls (31 children), of typically developing children with symptomatic intoeing gait who were treated by isolated supramalleolar tibial rotation osteotomy (28 children, with 45 treated extremities). Preoperative and 1-year postoperative physical examination, kinematic, kinetic, and pedobarographic data were compared. Patient-reported and parent-reported outcomes in functional and satisfaction domains were assessed by items on a 7-point questionnaire. RESULTS: Internal tibial torsion, foot progression angle, and knee rotation were normalized following tibial rotation osteotomy. Compensatory external hip rotation and external knee progression angle were significantly improved but not normalized following tibial rotation osteotomy. An increased coronal plane knee varus moment was significantly decreased following surgery. Increased sagittal and transverse plane knee moments were significantly decreased but not normalized following surgery. Significant improvements were observed with respect to tripping, falling, foot/ankle pain, and knee pain following surgery. CONCLUSIONS: Children with symptomatic intoeing gait because of increased internal tibial torsion have characteristic primary and compensatory kinematic gait deviations that result in increased loading about the knee during the stance phase of gait. Correction of the internal tibial torsion by rotation osteotomy improves, but does not normalize, all the kinematic and kinetic gait deviations associated with intoeing gait. The association between increased internal tibial torsion and degenerative arthritis of the knee in adults may be a consequence of longstanding increased loading of the knee joint due to the kinematic gait deviations seen with intoeing gait. LEVEL OF EVIDENCE: Therapeutic intervention, level III.