A blended e-health intervention for improving functional capacity in elderly patients on haemodialysis: A feasibility study.

Introduction: Physical exercise showed to be beneficial for frail older adults on haemodialysis (HD). However, there are several obstacles hindering the regular practice of exercise, such as transportation difficulties, lack of time, fatigue and comorbidities. E-health in this regard has many potential advantages and could be useful for motivating HD patients to increase their level of physical activity. The aim of this study was to evaluate the feasibility of a blended e-health intervention for elderly HD patients who individually exercise at home while under remote supervision of a physiotherapist. Material and methods: Patients over 60 years of age with sufficient cognitive and motoric resources to perform a simple physical test battery and to use a tablet-computer were recruited from four HD outpatient facilities. Following baseline assessment at home, the participants were visited by a physiotherapist (PT). The PT set an individual exercise programme and explained how to use the web-based interface. During the 12 weeks of training, the PTs remotely supervised the patients' progress. At 12 weeks follow-up a second assessment took place. Results: Twenty-two patients were recruited to participate in the study. Seven patients dropped out of the blended programme and 15 patients concluded the programme. The average training frequency of the 15 participants concluding the study was 1.5 times a week [range 0.2-5.8]. The duration of a training session was between 20 and 40 min. The usability of the system was deemed positive. Regarding the efficacy of the intervention, no significant improvement of any measured parameter was found, and effect sizes were small to medium. Conclusion: A blended e-health intervention supported by a web-based application for exercising at home under remote supervision of a PT is feasible in a HD population including older patients. However, before planning a randomized controlled trial, strategies to increase the recruitment rate and the adherence to such a blended intervention should be further developed, e.g., to improve the recruitment procedures and lower the expectable drop-out rate. Furthermore, the dosage of the blended programme should be adapted to the patients' physical performance levels in future trials.The study was registered on the website clinicaltrials.gov with ID NCT04076488.

A Pilot Observational Study Assessing Long-Term Changes in Clinical Parameters, Functional Capacity and Fall Risk of Patients With Chronic Renal Disease Scheduled for Hemodialysis.

BACKGROUND: Patients with end-stage renal disease are known to be particularly frail, and the cause is still widely seen as being directly related to specific factors in renal replacement therapy. However, a closer examination of the transitional phase from predialysis to long-term hemodialysis leads to controversial explanations, considering that the frailty process is already well-described in the early stages of renal insufficiency. This study aims to describe longitudinally and multifactorially changes in the period extending from the decision to start the replacement therapy through to the end of 2 years of hemodialysis. We hypothesized that frailty is pre-existent in the predialysis phase and does not worsen with the beginning of the replacement therapy. Between 2015 and 2018 we recruited 25 patients (72.3 ± 5.7 years old) in a predialysis program, with the expectation that replacement therapy would begin within the coming few months. METHODS: The patients underwent a baseline visit before starting hemodialysis, with 4 follow-up visits in the first 2 years of treatment. Health status, physical performance, cognitive functioning, hematology parameters, and adverse events were monitored during the study period. RESULTS: At baseline, our sample had a high variability with patients ranging from extremely frail to very fit. In the 14 participants that did not drop out of the study, out of 32 clinical and functional measures, a statistically significant worsening was only observed in the Short Physical Performance Battery (SPPB) score (p < 0.01, F = 8.50) and the number of comorbidities (p = 0.01, F = 3.94). A careful analysis, however, reveals a quite stable situation in the first year of replacement therapy, for both frail and fit participants and a deterioration in the second year that in frail participants could lead to death. CONCLUSION: Our results should stimulate a reassessment about the role of a predialysis program in reducing complications during the transitional phase, but also about frailty prevention programs once hemodialysis has begun, for both frail and fit patients, to maintain satisfactory health status.

Gait disorders in CKD patients: muscle wasting or cognitive impairment? A cross-sectional pilot study to investigate gait signatures in Stage 1-5 CKD patients.

BACKGROUND: Instrumental gait analysis in nephrology is widely neglected, although patients with chronic kidney disease (CKD) show brain changes due to cerebrovascular disease and metabolic disorders that can potentially influence gait quality. Our study assesses the association between CKD stages and gait parameters, to understand the prevalent status of brain related gait parameters (i.e. variability) and of performance related parameters (i.e. gait speed, stride length). We hypothesize that gait changes are detectable already in early stages of CKD. METHODS: Forty-five participants distributed in 5 CKD severity groups underwent an instrumental gait analysis via a triaxial accelerometer affixed to the lower trunk under single- and dual-task conditions. In addition to spatio-temporal parameters, variability and dual-task cost of gait were extracted. A battery of clinical assessments was conducted with the aim of helping to better explain the findings of the gait analysis. A correlation analysis was made to investigate a linear relation between gait parameters and CKD severity. RESULTS: Statistically significant correlations (Pearson correlation coefficient) with CKD severity were found for gait speed (p < 0.01, r = -0.55, 95% CI [-0.73;-0.30]), stride length ( p < 0.01, r = -0.40, 95% CI [-0.62;-0.12]), step length (p < 0.01, r = -0.41, 95% CI [-0.63;-0.13], coefficient of variance (CV) of step length (p = 0.01, r = 0.36, 95% CI [0.08;0.59]), gait regularity (p < 0.01, r = -0.38, 95% CI [-0.61;-0.10]), dual-task cost of gait speed (p < 0.01, r = 0.40, 95% CI [0.13;0.62]) and dual-task cost of stride time (p = 0.03, r = 0.32, 95% CI [0.03;0.57]). Adjustment for age and gender confirmed all results except for gait regularity. With increasing severity of renal failure, Handgrip strength, Time for the Expanded Timed Get Up and Go test, executive functions, haemoglobin, and haematocrit, worsen. CONCLUSIONS: The correlation of CKD severity with spatio-temporal parameters (performance indices mainly relatable to peripheral functionality) and with variability of gait (related to central factors) supported by the results of the clinical assessments, suggests that gait disturbance in CKD patients is not only due to metabolic factors that lead to muscle wasting, but also to brain changes that affect motor control. This suggests that the treatment of renal disease should include cognitive aspects in addition to metabolic and functional factors.

Stabilization after postural transitions in the elderly: Experimental study on community-dwelling subjects and nursing home residents.

BACKGROUND: Postural transitions have been identified as presenting challenging situations for the elderly. RESEARCH QUESTION: This study hypothesizes a relationship between age-related factors and postural stabilization performance after a transition movement. In particular, the controlled factors in the experiment are: 1) assistance in living (independent living for community-dwelling subjects vs. assisted living for institutionalized subjects in nursing homes); 2) age of institutionalized individuals, by comparing groups with different age ranges. METHODS: Sixty-three institutionalized individuals in nursing homes were recruited (17 in the age range 64-79; 46, including 6 drop-outs, in the age range 80-95). Moreover, seventeen (one drop out) community dwelling subjects (64-79 years) were enlisted. The study focuses on the postural stabilization phase after a "step forward" task. RESULTS: When comparing age-matched subjects from the two groups, the residents in nursing homes were characterised by a worse stabilization performance: the stabilization time more than doubled, Instability increased by 39 %, and Promptness decreased by 77 %, although there was no significant difference in the quiet erect posture between the groups. No difference was observed when comparing the two age groups of residents in the nursing homes, however a potential confounding effect has been identified in the unequal mortality rates between the two groups. SIGNIFICANCE: It is hypothesized that an individual identification of abnormal values of Instability and/or Promptness may inform different rehabilitation approaches.

Signatures of Gait Movement Variability in CKD Patients Scheduled for Hemodialysis Indicate Pathological Performance Before and After Hemodialysis: A Prospective, Observational Study.

Background: The frailty status of hemodialysis patients is well-known, but the role of the therapy in the frailty process is not yet clear. Nowadays gait analysis in nephrology is neglected, although gait performance is known to be related to frailty and kidney function. We hypothesized that gait quality and physical activity level is already affected before, and does not change because of the start of hemodialysis. Methods: Fourteen patients (72.3 ± 5.7 years old) in a pre-dialysis program underwent an instrumental gait analysis and their physical activity was monitored for a week. This protocol was repeated 3, 6, 12, and 24 months after the first hemodialysis session. Results: At baseline, our sample showed a conservative gait with pathologic gait variability, high dual-task cost, and a sedentary lifestyle. No statistically significant change was found in any parameter in the analyzed period, but there was a tendency toward an improvement of gait quality and physical activity in the first year of treatment, and a decline in the second year. Conclusion: Elderly patients in the pre-dialysis stage show a conservative gait, however variability was in a pathological range and did not change post-hemodialysis. This hints toward changes in the central nervous system due to the kidney disease. This finding suggests the importance of gait analysis in the early stages of renal disease in the diagnosis of changes in the nervous system due to kidney failure that affect gait. Early detection of these changes would potentially allow a prevention program tailored to this population to be developed.

Gait characteristics of CKD patients: a systematic review.

BACKGROUND: People with Chronic Kidney Disease (CKD) often present with prevalent gait impairment and high fall rates, particularly in advanced CKD stages. Gait impairment and its consequences is associated with increased hospital admission, institutionalization, and greater need for health care. The objective of this systematic review was to evaluate the quality of studies investigating CKD patients' gait characteristics at different CKD stages, to highlight areas of agreement and contradiction between studies reporting aspects of gait in CKD, and to discuss and emphasize gait parameters associated with fall risk. METHODS: We performed a literature search of trials in CINAHL (EBSCO), Cochrane Library, EMBASE, Medline (EBSCO), PEDro, PubMed, and Scopus databases from their inception to June 30th 2018 using a two-stage process for the identification of studies. We retrieved English-, German-, Italian-, Spanish-, Portuguese and Dutch-language articles for review. Methodological quality of randomized and non-randomized studies was assessed with an adapted version of the Downs and Black checklist. RESULTS: Thirty-one studies (22 cross-sectional with 3901 participants) and 9 longitudinal intervention studies (1 randomized control trial, 5 controlled clinical trials and 3 one-group pre-post-test; with 659 participants) were considered. The studies revealed a primary emphasis on gait speed measures within clinical tests, and a neglect of spatiotemporal gait variables. Most of the studies showed that CKD progression is associated with slowing of walking speed. No studies analysed the relation between gait parameters and fall risk. CONCLUSIONS: There was a paucity of studies investigating aspects of gait quality in patients with CKD. In the majority of studies, only gait speed is analysed as a performance indicator. The relation between gait parameters and fall risk in CKD is not investigated. We formulate several recommendations to fill the current research gap, encourage the use of standardized gait analysis protocols that include assessment of spatiotemporal parameters in clinical care of patients with CKD, aimed at prevention of mobility decline and falls risk.

Clinical validity of novel postural stabilization experimental indices based on hyperbolic transformation.

BACKGROUND: Postural stabilization is the function which allows an individual, after a transitional movement, to recover balance in a quiet erect posture. An experimental method has been proposed (Rabuffetti, 2011) and proved valid for the assessment of balance disorders in individuals with neurological diseases. It would seem that the two original indices were not fully independent since their concurrent distribution was confined by a hyperbolic boundary. RESEARCH QUESTION: A methodological advancement involving non-linear transformation techniques is required to overcome the limitations of the original approach. METHODS: A hyperbolic transformation is applied to the original indices related to the mechanics of the stabilization (instability at beginning of stabilization and time rate of stabilization), thus defining two novel indices (Instability and Promptness). These novel indices may be related to different functional domains concerning, respectively, peripheral force capacity and central nervous motor control. The validity of these novel indices is quantified by their correlation with clinical scales in an already validated group of patients with Charcot-Marie-Tooth disease (N = 47) or Multiple Sclerosis (N = 20). RESULTS: The novel indices generally improved validity compared to the original indices (+66% of indices show a statistically significant concurrent validity on a clinical scale). Moreover, Instability was more related to the Charcot-Marie-Tooth group (9 out of 12 valid correlations), and Promptness to the Multiple Sclerosis group (4 out of 5, when also considering statistical trends), in accordance to the, respectively, more peripheral and more central nature of the two neurological diseases. SIGNIFICANCE: The novel postural stabilization indices support a clinical application for two reasons: 1) they have shown improved validity, compared to the original indices, in two groups of patients affected by neurological pathologies of different nature, 2) they are more closely related, compared to the original indices, to different functional domains.

Characteristics associated with improved knee extension after strength training for individuals with cerebral palsy and crouch gait.

Muscle weakness may contribute to crouch gait in individuals with cerebral palsy, and some individuals participate in strength training programs to improve crouch gait. Unfortunately, improvements in muscle strength and gait are inconsistent after completing strength training programs. The purpose of this study was to examine changes in knee extensor strength and knee extension angle during walking after strength training in individuals with cerebral palsy who walk in crouch gait and to determine subject characteristics associated with these changes. A literature review was performed of studies published since January 2000 that included strength training, three-dimensional motion analysis, and knee extensor strength measurements for individuals with cerebral palsy. Three studies met these criteria and individual subject data was obtained from the authors for thirty crouch gait subjects. Univariate regression analyses were performed to determine which of ten physical examination and motor performance variables were associated with changes in strength and knee extension during gait. Change in knee extensor strength ranged from a 25% decrease to a 215% increase, and change in minimum knee flexion angle during gait ranged from an improvement of 9° more knee extension to 15° more knee flexion. Individuals without hamstring spasticity had greater improvement in knee extension after strength training. Hamstring spasticity was associated with an undesired increase in knee flexion during walking. Subject-specific factors such as hamstring spasticity may be useful for predicting which subjects will benefit from strength training to improve crouch gait.

Outcome tools used for ambulatory children with cerebral palsy: responsiveness and minimum clinically important differences.

This prospective longitudinal multicenter study of ambulatory children with cerebral palsy (CP) examined changes in outcome tool score over time, tool responsiveness, and used a systematic method for defining minimum clinically important differences (MCIDs). Three hundred and eighty-one participants with CP (Gross Motor Function Classification System [GMFCS] Levels I-III; age range 4-18y, mean age 11y [SD 4y 4mo]; 265 diplegia, 116 hemiplegia; 230 males, 151 females). At baseline and follow-up at least 1 year later, Functional Assessment Questionnaire, Gross Motor Function Measure, Pediatric Quality of Life Inventory, Pediatric Outcomes Data Collection Instrument, Pediatric Functional Independence Measure, temporal-spatial gait parameters, and oxygen cost were collected. Adjusted standardized response means determined tool responsiveness for nonsurgical (n=292) and surgical (n=87) groups at GMFCS Levels I to III. Most scores reaching medium or large effect sizes were for GMFCS Level III. Nonsurgical group change scores were used to calculate MCID thresholds for ambulatory children with CP. These values were verified by examining participants who changed GMFCS levels. Tools measuring function were responsive when a change large enough to cause a change in GMFCS level occurred. MCID thresholds assess change in study populations over time, and serve as the basis for designing prospective intervention studies.

Testing and reducing skindex-29 using Rasch analysis: Skindex-17.

The Skindex is a well-studied dermatology-specific health-related quality of life (HRQOL) instrument. The objective of this study was to test Skindex-29 using Rasch analysis and, if necessary, to refine it so that it would fit this item response theory based model. The Skindex-29 of 454 Italian dermatological patients was subjected to Rasch analysis to investigate threshold order, differential item functioning (DIF), and item and overall fit to the model. The Skindex-29 did not fit the Rasch model (P<0.001). The 5-point scoring system was re-grouped into three categories and demonstrated logical response order for all but one item. Rasch analyses of a combined emotion and social functioning subscale of Skindex-29 resulted in a 12-item psychosocial subscale. Five of seven items were retained in a symptoms subscale. Both subscales fitted the model (P=0.32 and 0.13, respectively) without significant individual item misfit or DIF (P>0.05). Classical psychometric properties such as response distribution, item-rest correlation, item complexity, and internal consistency of the two subscales of Skindex-17 were at least adequate. The Skindex-17 is a Rasch reduced version of Skindex-29, with two independent scores that can be used in the measurement of HRQOL in dermatological patients.

Gross Motor Function Classification System and outcome tools for assessing ambulatory cerebral palsy: a multicenter study.

The relationships between different levels of severity of ambulatory cerebral palsy, defined by the Gross Motor Function Classification System (GMFCS), and several pediatric outcome instruments were examined. Data from the Gross Motor Function Measure (GMFM), Pediatric Orthopaedic Data Collection Instrument (PODCI), temporal-spatial gait parameters, and oxygen cost were collected from six sites. The sample size for each assessment tool ranged from 226 to 1047 participants. There were significant differences among GMFCS levels I, II, and III for many of the outcome tools assessed in this study. Strong correlations were seen between GMFCS level and each of the GMFM sections D and E scores, the PODCI measures of Transfer and Mobility, and Sports and Physical Function, Gait Velocity, and Oxygen Cost. Correlations among tools demonstrated that the GMFM sections D and E scores correlated with the largest number of other tools. Logistic regression showed GMFM section E score to be a significant predictor of GMFCS level. GMFM section E score can be used to predict GMFCS level relatively accurately (76.6%). Study data indicate that the assessed outcome tools can distinguish between children with different GMFCS levels. This study establishes justification for using the GMFCS as a classification system in clinical studies.

Torque-EMG relationships in normal and spastic muscles.

The linearity of the relationship between torque and electromyographic (EMG) activation has been widely debated for years, yet remains unresolved. Despite limitations and possible inaccuracies, an assumption of linearity is often made to simplify the relationship between these variables for computational and descriptive purposes. Although typically derived from isometric test conditions, these relationships have also been extrapolated, perhaps invalidly, to conditions where joint velocity and length are changing. The purpose of this study was to examine the degree of linearity between hamstring and quadriceps torques and their respective EMG signals, and to compare the slopes of these relationships in normal and spastic muscles at varying muscle lengths and conditions. We hypothesized that relationships would be linear for all muscles tested in both subject groups; however, slopes would differ across the two muscles, the three muscle lengths tested, and the two subject groups. We further hypothesized that the degree of linearity during an isotonic task would be less than for the isometric one, particularly for patients with spasticity who may demonstrate abnormal responses to changes in muscle length. Results indicated that torque--EMG relationships were linear for all subjects during isometric contractions, regardless of group, muscle, or knee angle. However, the degree of linearity was significantly less in CP in both conditions; and within the CP group, was less during isotonic compared to isometric conditions. Slope values differed between muscles at some lengths, across muscle lengths in the quadriceps, and subjects with CP showed consistently lower slopes for all quadriceps values. These data in general support the robustness of the linear assumption in isometric conditions for the knee musculature, caution against extrapolation to isotonic conditions particularly for those with movement abnormalities, and suggest that slope differences may provide valuable insights into pathology and warrant further investigation.

Deficits in eccentric versus concentric torque in children with spastic cerebral palsy.

PURPOSE: The purposes of this study were to determine whether ambulatory children with spastic cerebral palsy (CP) had abnormal isokinetic eccentric peak torque values at the knee and ankle, and to gain further insights on the influence of spasticity on voluntary force production in this population. METHODS: Twenty-four children with spastic CP (mean = 11.1+/-2.6 yr) and twenty children of comparable age with no neuromotor pathology (mean = 10.3+/-2.6 yr) participated in an isokinetic testing protocol on a Biodex dynamometer that measured eccentric and concentric peak torques of the knee extensors, knee flexors, ankle dorsiflexors, and ankle plantarflexors. Angular velocity of the eccentric trials was 30 degrees x s(-1) and of the concentric trials was 30 degrees x s(-1), 60 degrees x s(-1), and 120 degrees x s(-1). Peak torque values were normalized by body weight and compared across groups by using ANOVA procedures. Eccentric to concentric (E/C) peak torque ratios at 30 degrees x s(-1) were computed for each muscle and compared across groups. The torque values in CP were also expressed as a percent of the mean normalized value of the comparison group and compared across conditions using repeated measures ANOVA (P < 0.05). RESULTS: Children with CP demonstrated decreased eccentric and concentric peak torques for all muscle groups tested. The relative deficit in eccentric torque was less than the concentric torque and the decrement in concentric torque across speeds was greater in CP for all muscle groups except the ankle dorsiflexors. The E/C ratios for the knee extensors and flexors were also greater in CP. CONCLUSIONS: Children with CP have diminished eccentric as well as concentric peak torques at the knee and ankle. The influence of spasticity on voluntary force production can be inferred from the bias toward greater eccentric torque and the greater decrement in concentric torque across speeds in children with spastic CP.

Spasticity versus strength in cerebral palsy: relationships among involuntary resistance, voluntary torque, and motor function.

Despite the lack of consensus of the role of spasticity in the observed motor disability in cerebral palsy (CP), alleviation of spasticity remains a primary focus in the clinical management of these patients. The purposes of this study were to: (1) quantify voluntary torque and passive resistance across speeds in the hamstrings and quadriceps muscle groups with respect to the presence of stretch responses and/or passive muscle stiffness in patients with CP compared to age-related children without disability, and (2) relate these parameters to each other and to functional performance, as measured by the Gross Motor Function Measure (GMFM), in CP. Included were 23 subjects with CP, sub-grouped by the presence or absence of stretch responses as determined by electromyography, and 9 subjects without CP. Results indicated that peak torque was considerably greater in the comparison group than for each of the CP groups and resistance was greater in the CP group with spasticity compared to the nonspastic CP group in both muscles at all speeds. Stiffness differed between the spastic CP group and the comparison group only for the quadriceps at the fastest speed. Higher passive resistance torque and stiffness were correlated with decreased voluntary torque, particularly for the antagonists, and with lower GMFM scores. In conclusion, strength and motor function are related to the magnitude of resistance torque and stiffness in CP, although the small amount of variance explained reinforces the multidimensional nature of this disorder, and the challenges inherent in managing it.

Muscle force production and functional performance in spastic cerebral palsy: relationship of cocontraction.

OBJECTIVE: To determine cocontraction's relation to strength and motor function in children with spastic cerebral palsy (CP). DESIGN: Prospective evaluation with a convenience sample of 10 subjects. SETTING: Pediatric rehabilitation center at a tertiary care hospital. PATIENTS: Ten ambulatory children with spastic CP, mean age 5 to 14yrs. MAIN OUTCOME MEASURES: A single comprehensive assessment of hamstring and quadriceps muscle strength; gait analysis while monitoring electromyographic (EMG) activity in those muscles; administration of the Gross Motor Function Measure (GMFM); heart-rate monitoring during quiet rest versus gait to compute an energy expenditure index (EEI). Cocontraction ratios and magnitudes were determined for the gait and strength testing trials using the EMG data. RESULTS: Cocontraction ratios during strength tests correlated directly with those during free gait. Cocontraction magnitude and total EMG magnitude had an inverse relationship to EEI; children with more muscle activity in the agonist and antagonist tended to be more energy efficient. Knee extensor muscle strength correlated positively with the GMFM and gait velocity. Neither cocontraction ratio nor magnitude during gait was related to strength. CONCLUSIONS: Children with CP used a similar muscle activation strategy across two different motor tasks. Strength and cocontraction were uniquely related to different aspects of motor function. Further research is needed to quantify more precisely cocontraction and force to EMG relations in this population.

Joint angular velocity in spastic gait and the influence of muscle-tendon lengthening.

BACKGROUND: Joint angular velocity (the rate of flexion and extension of a joint) is related to the dynamics of muscle activation and force generation during walking. Therefore, the goal of this research was to examine the joint angular velocity in normal and spastic gait and changes resulting from muscle-tendon lengthening (recession and tenotomy) in patients who have spastic cerebral palsy. METHODS: The gait patterns of forty patients who had been diagnosed with spastic cerebral palsy (mean age, 8.3 years; range, 3.7 to 14.8 years) and of seventy-three age-matched, normally developing subjects were evaluated with three-dimensional motion analysis and electromyography. The patients who had cerebral palsy were evaluated before muscle-tendon lengthening and nine months after treatment. RESULTS: The gait patterns of the patients who had cerebral palsy were characterized by increased flexion of the knee in the stance phase, premature plantar flexion of the ankle, and reduced joint angular velocities compared with the patterns of the normally developing subjects. Even though muscle-tendon lengthening altered sagittal joint angles in gait, the joint angular velocities were generally unchanged at the hip and knee. Only the ankle demonstrated modified angular velocities, including reduced dorsiflexion velocity at foot-strike and improved dorsiflexion velocity through mid-stance, after treatment. Electromyographic changes included reduced amplitude of the gastrocnemius-soleus during the loading phase and decreased knee coactivity (the ratio of quadriceps and hamstring activation) at toe-off. Principal component analyses showed that, compared with joint-angle data, joint angular velocity was better able to discriminate between the gait patterns of the normal and cerebral palsy groups. CONCLUSIONS: This study showed that muscle-tendon lengthening corrects biomechanical alignment as reflected by changes in sagittal joint angles. However, joint angular velocity and electromyographic data suggest that the underlying neural input remains largely unchanged at the hip and knee. Conversely, electromyographic changes and changes in velocity in the ankle indicate that the activation pattern of the gastrocnemius-soleus complex in response to stretch was altered by recession of the complex.

Asymmetric hip deformity and subluxation in cerebral palsy: an analysis of surgical treatment.

Thirty-seven cerebral palsy patients were followed with measurements of the migration index (MI), infrapelvic obliquity, and suprapelvic obliquity over a mean period of 73 months to evaluate the development of the windblown deformity. The infrapelvic asymmetry was apparent before the suprapelvic obliquity; however, 65% eventually had both. The final pattern of infrapelvic obliquity and the most subluxed hip could not be predicted from initial radiographs or from the pattern of scoliosis. Hip subluxation strongly correlated with the degree of femoral adduction and weakly with the magnitude of suprapelvic obliquity. The suprapelvic obliquity and scoliosis increased over time and influenced the final windblown appearance. Soft-tissue surgeries did not have a significant effect on the final MI. Severe abduction deformities generally followed ipsilateral adductor releases. Finally, despite improvement in the MI of the initially more subluxed hip, 33% of patients still had one hip with a MI >50%.

Interrelationships of strength and gait before and after hamstrings lengthening.

Muscle-tendon lengthenings are an essential part of the orthopaedic management of static and dynamic joint contractures associated with cerebral palsy. Although these procedures typically have a positive biomechanical effect on joint alignment, the potential negative effects of alterations in tendon length on muscle strength and gait function have not been well documented in these patients, in whom muscle weakness is a prevalent clinical symptom. The purpose of this study was to examine the change in strength values of the hamstring and quadriceps muscle groups during a 9-month postoperative period in patients who had undergone hamstring tendon lengthenings, in comparison to an operative "no hamstring surgery" control group, and to relate baseline strength and postoperative changes to gait function in these patients. Results for the "hamstring surgery" group indicated that although hamstring strength declined initially, the strength increased with time and was similar to preoperative values by 9 months. Quadriceps strength measured at 30 degrees of knee flexion increased significantly during the recovery period as a direct result of improvements in knee extension. Although hamstring surgery produced an immediate effect on passive motion and knee-joint alignment, functional improvement, as evidenced by increased stride length, was not evident until strength values approximated or exceeded preoperative values.

Muscle-tendon surgery in diplegic cerebral palsy: functional and mechanical changes.

A prospective assessment of muscle-tendon (M-T) surgery was conducted on 30 patients with spastic diplegia. Muscle-tendon surgery consisted of recessions or releases to improve gait function by correcting restricted joint motion and joint malalignment. Functional-outcome measures included the Gross Motor Function Measure (GMFM) and temporal gait factors. Kinematic gait data were evaluated to determine the mechanical effects. The mean age at surgery was 8.7 years (4-20 years), and 3.5 muscle tendon units per extremity were recessed or released at surgery. The primary kinematic change for the hip and the knee was a shift in the sagittal joint position with minimal effects on overall excursion. Changes in ankle-joint dynamics after gastrocsoleus recessions included a reduction in plantarflexion and a shift in the timing of maximal dorsiflexion to later in stance. Improvements in walking velocity and stride length were evident by 6 month after surgery. Functional changes from M-T surgery included a 25% increase in velocity and an 18% increase in stride length over preoperative values seen at 9 months after surgery. Improvements in these parameters were maintained at 2 years after surgery. The GMFM total score showed minimal change after surgery with improvements occurring primarily in the standing dimension and the walking, running, and jumping dimensions.