Ankle Power Generation Research Articles

Longitudinal kinematic and kinetic adaptations to obstacle crossing in recent lower limb amputees

Obstacle crossing is an important activity of daily living, necessary to avoid tripping or falling, although it is not fully understood how transtibial amputees adapt to performing this activity of daily living following discharge from rehabilitation. The objective of this study was to investigate the longitudinal adaptations in obstacle crossing in transtibial amputees post-discharge from rehabilitation. Longitudinal repeated measures. Seven unilateral transtibial amputees crossed an obstacle 0.1m high positioned along a walkway while kinematic and kinetic data were recorded at 1, 3 and 6 months post-discharge. At 6 months post-discharge, walking velocity had increased (0.17 m.s(-1)) with most participants self-selecting an intact lead limb preference. During swing phase, peak knee flexion (p = 0.03) and peak knee power absorption (K4; p = 0.01) were greater with an intact versus affected lead limb preference. Having crossed the obstacle, intact limb peak ankle power generation in pre-swing (A2; p = 0.01) and knee power absorption (K3; p = 0.05) during stance phase were greater when compared to the affected limb. Obstacle crossing improved, although a greater reliance on intact limb function was highlighted. Results suggested that further improvements to locomotor performance may be obtained by increasing affected limb knee range of motion and concentric and eccentric strength of the knee extensors and flexors. The novel objective data from this study establish an understanding of how recent transtibial amputees adapt to performing obstacle crossing following discharge from rehabilitation. This allows for evidence-based clinical interventions to be developed, aimed at optimising biomechanical function, thus improving overall locomotor performance and perhaps subsequent quality of life.

“The problem with running”—Comparing the propulsion strategy of children with Developmental Coordination Disorder and typically developing children

Children with Developmental Coordination Disorder (DCD) often have difficulties running. This study compared strategies of propulsion and power generation at the ankle during late stance/early swing in both walking and running in children with and without DCD. Eleven children (six male) aged nine to 12 years with DCD were matched by sex and age with 11 typically developing (TD) children. Gait kinematics and kinetics were measured during 4 gait types; normal walking, fast walking, jogging and sprinting using three-dimensional motion analysis. Propulsion strategy during gait was calculated as ankle power divided by the sum of ankle and hip power (A2/A2+H3). The children with DCD ran slower than the TD children (mean difference [MD] when jogging 0.3m/s and sprinting 0.8m/s). Adjusting for speed, those with DCD had smaller propulsion strategy values during jogging (p=0.001) and sprinting (p=0.012), explained by reduced ankle power generation at push off (A2) (jogging, MD 2.5W/kg, p<0.001) and greater hip flexor power generation at pull off (H3) (jogging, MD 0.75W/kg, p=0.013). Similar findings were observed during sprinting. Children with DCD ran with a slow and less efficient running style compared with TD children. Physiotherapy targeting running-specific needs in relation to ankle muscle strength and coordination could enable more participation in running activities.

Mobility After Traumatic Brain Injury

Reduced balance, spasticity, contractures, muscle weakness, and motor skill levels may all contribute to mobility limitations after traumatic brain injury (TBI), yet the key physical impairments that contribute to mobility limitations remain unclear. The aim of this study was to determine which physical impairments best predict mobility performance after a period of 6 months of rehabilitation. Participants with TBI were selected if they were receiving therapy for mobility limitations but were able to walk without physical assistance. The clinical assessment included measures of balance, spasticity, and contracture, and 3-dimensional quantitative gait analysis was used to quantify joint power generation and motor skill level on 31 adults with severe TBI. Mobility outcome was quantified with the high-level mobility assessment tool. Two variables, ankle joint power generation during the push-off phase of gait and motor skill level, explained 66.5% of the variability in mobility outcome. Balance, strength, and mobility performance, all improved significantly over the 6 months of rehabilitation. Only 2 participants had contractures, which affected mobility. Balance disorders were prevalent and improved with rehabilitation, yet they contributed to only a limited extent to the level of recovery in mobility. Ankle joint power generation at push-off was the strongest predictor of mobility outcome after 6 months of rehabilitation in ambulant people with TBI.

Self-Selected Walking Speed Predicts Ability to Run Following Traumatic Brain Injury

To identify factors that predict running ability following traumatic brain injury (TBI), and to quantify performance thresholds for these predictors. Cross-sectional cohort study. One hundred fourteen people with TBI. Self-selected walking speed, the high-level mobility assessment tool, postural stability (lateral center of mass displacement), ankle power generation at push-off and quality of gait performance (Gait Profile Score). All predictor variables were all strongly associated with the ability to run. However, only self-selected walking speed contributed significantly to the final result. Investigation of performance thresholds for self-selected walking speed indicated that following TBI, people who walk at speeds of 1.0 m/s or higher are 16.9 times more likely of being able to run than for those who walk at speeds of less than 1.0 m/s. Self-selected walking speeds higher than 1.0 m/s greatly increase the likelihood of running following brain injury. The 1.0 m/s threshold, although slower than able-bodied self-selected walking speeds, may be an important indicator of the ability to run in this population.

Advanced age and the mechanics of uphill walking: A joint-level, inverse dynamic analysis

We sought to gain insight into age-related muscular limitations that may restrict the uphill walking ability of old adults. We hypothesized that: (1) old adults would exhibit smaller peak ankle joint kinetics and larger peak hip joint kinetics than young adults during both level and uphill walking and (2) these age-related differences in ankle and hip joint kinetics would be greatest during uphill vs. level walking. We quantified the sagittal plane ankle, knee, and hip joint kinetics of 10 old adults (mean±SD, age: 72±5yrs) and 8 young adults (age: 27±5yrs) walking at 1.25m/s on a dual-belt, force-measuring treadmill at four grades (0°, +3°, +6°, +9°). As hypothesized, old adults walked with smaller peak ankle joint kinetics (e.g., power generation: −18% at +9°) and larger peak hip joint kinetics (e.g., power generation: +119% at +9°) than young adults, most evident during the late stance phase of both level and uphill conditions. Old adults performed two to three times more single support positive work than young adults via muscles crossing the knee. In partial support of our second hypothesis, the age-related reduction in peak ankle joint moments was greater during uphill (−0.41Nm/kg) vs. level (−0.30Nm/kg) walking. However, old adults that exhibited reduced propulsive ankle function during level walking could perform 44% more trailing leg positive ankle joint work to walk uphill. Our findings indicate that maintaining ankle power generation and trailing leg propulsive function should be the primary focus of “prehabilitation” strategies for old adults to preserve their uphill walking ability.

Biomechanics of slow running and walking with a rocker shoe

Evidence suggests a link between the loading of the Achilles tendon and the magnitude of the ankle internal plantar flexion moment during late stance of gait, which is clinically relevant in the management of Achilles tendinopathy. Some studies showed that rocker shoes can reduce the ankle internal plantar flexion moment. However, the existing evidence is not conclusive and focused on walking and scarce in running. Sixteen healthy runners participated in this study. Lower extremity kinetics, kinematics and electromyographic (EMG) signals of triceps surae and tibialis anterior were quantified for two types of shoes during running and walking. The peak ankle plantar flexion moment was reduced significantly in late stance of running (0.27Nm/kg; p<0.001) and walking (0.24Nm/kg; p<0.001) with the rocker shoe compared to standard shoe. The ankle power generation and plantar flexion moment impulse were also reduced significantly when running and walking with the rocker shoe (p<0.001). No significant changes in the knee and hip moments were found in running and walking. A significant delay of the EMG peak, approximately 2% (p<0.001), was present in the triceps surae when walking with rocker shoes. There were no significant changes in the EMG peak amplitude of triceps surae in running and walking. The peak amplitude of tibialis anterior was significantly increased (64.7μV, p<0.001) when walking with rocker shoes. The findings show that rocker shoes reduce the ankle plantar flexion moment during the late stance phase of running and walking in healthy people.

A comprehensive evaluation of the variation in ankle function during gait in children and youth with Charcot–Marie–Tooth disease

A better understanding of gait dysfunction for children and youth with Charcot–Marie–Tooth (CMT) will assist in developing appropriate treatments and understanding prognosis for ambulation. The purpose of this retrospective study was to document the typical gait patterns in children and youth (12±4 years) with CMT using motion analysis and relate these findings back to the clinical assessment at the ankle. All patients underwent a motion analysis as a component of treatment decision-making.Lower extremity kinematics and kinetics were evaluated in comparison to a typically developing age-matched reference control group collected in the same gait laboratory. Three patient subgroups were defined based on peak ankle dorsiflexion in terminal stance: greater than typical (n=23), within typical range (n=30) and less than typical (n=13). The three subgroups showed statistically significant differences (p<0.004) in degree of impairment for ankle plantar flexor and dorsiflexor weakness and ankle plantar flexor contracture. Patients with excessive dorsiflexion in terminal stance had the greatest ankle plantar flexor weakness (median 2) and the greatest dorsiflexor weakness (median 4). Patients with less than typical dorsiflexion in terminal stance were the only patients with a plantar flexor contracture (−2±9°). Delayed peak dorsiflexion in stance was the most common kinematic finding and consistent with ankle plantar flexor weakness. All patients showed significantly less (p<0.001) peak ankle moments and power generation in terminal stance than the typically developing controls. We concluded that children and youth with CMT present differently in terms of impairment and associated gait issues which therefore require patient specific treatment strategies.

Lower Limb Biomechanics in Individuals With Knee Osteoarthritis Before and After Total Knee Arthroplasty Surgery

We investigated the biomechanical changes that occur in the lower limb following total knee arthroplasty (TKA). Lower limb joint kinematics and kinetics were evaluated in 32 patients before and 12months following TKA and 28 age-matched controls. Analysis of variance with Bonferroni-adjusted post-hoc tests showed no significant changes in knee joint kinematics and kinetics following TKA despite significant improvements in pain and function. Significant increases in peak ankle plantarflexion and dorsiflexion moments and ankle power generation were observed which may be a compensatory response to impaired knee function to allow sufficient power generation for propulsion. Differences in knee gait parameters may arise as a result of the presence of osteoarthritis and mechanical changes associated with TKA as well as retention of the pre-surgery gait pattern.

Running abnormalities after traumatic brain injury

Primary objectives: The aim of this study was to identify the type and incidence of running abnormalities following TBI when compared to a group of healthy controls (HC) and report if these abnormalities were similar to those which are present during gait.Research design: A convenience sample of 44 people with TBI receiving therapy for mobility limitations and a sample of 15 healthy controls (HCs).Main outcomes and results: Spatio-temporal, kinematic and kinetic data at self-selected walking and running speeds were collected. People with TBI ran at significantly slower self-selected speeds than HCs. At matched running speeds, people with TBI used a higher cadence and shorter step length. The most commonly observed biomechanical abnormalities occurred at the knee during stance phase. Few trunk, pelvic or hip abnormalities were detected. Ankle power generation at push-off was significantly reduced, whereas hip extensor power generation at initial contact was significantly increased.Conclusion: Many people with TBI may actually be capable of running, despite the presence of significant biomechanical abnormalities during gait. A stable trunk may be an important requirement for people following TBI to achieve running.

Threshold of equinus which alters biomechanical gait parameters in children

The main aim of this study was to define the threshold angle of equinus beyond which significant changes in 3D lower limb kinematics and kinetics occur in typically developing children and to describe these changes.A customized orthosis was fitted on the right ankle of 10 typically developing children and was adjusted to +10° ankle dorsiflexion, 0°, −10°, −20° plantarflexion and maximum plantarflexion. Gait was analyzed using an optoelectronic system. A gait velocity of 1m/s was imposed.Most of the kinematic and kinetic changes were significantly altered from the −10° condition. In the sagittal plane, the results showed increased knee flexion at initial contact, increased knee flexion or hyperextension in stance, increased hip flexion at initial contact and increased anterior pelvic tilt. Other changes included increased knee varus, reduced hip adduction and more internal foot progression. The ankle plantarflexion moment was bi-phasic during stance, peak ankle power generation was reduced, peak knee extension moment was decreased and hip extension moments increased. On the contralateral side, there was a significant increase in ankle plantarflexion at initial contact and a significant decrease in knee flexion during swing phaseat maximum plantarflexion.Although slight modifications occurred for smaller degrees of equinus, the results suggest that significant kinematic and kinetic changes occurred during gait in both limbs from 10° of plantarflexion. The results of this study also provide some indications regarding the primary causes of gait deviations and secondary compensatory strategiesin children with a clinical dorsiflexion limitation.

A comparison of running kinematics and kinetics in children with and without developmental coordination disorder

The aim of this study was to compare running gait in children with and without developmental coordination disorder (DCD). Fourteen boys with DCD (9.5±1 yr) and 14 typically developing (TD) controls (9.6±1 yr) ran at a velocity of 2.44±0.25m/s along a 15m track, with kinematic and kinetic data of the trunk and lower limb obtained for three cycles of each limb using a 12-camera Vicon MX system and AMTI force plate. Although features of the kinematic and kinetic trajectories were similar between groups, the DCD group displayed decreased peak knee extension compared with the TD group prior to initial foot contact (p=0.016). Furthermore, the DCD group displayed increased variability in sagittal plane kinematics at the hip and ankle during toe off compared with the TD group. Kinetic analysis revealed that children with DCD displayed significantly reduced knee extensor moments during the stance phase of the running cycle (p=0.033). Consequently, peak knee power absorption and ankle power generation was significantly lower in the DCD group (p=0.041; p=0.017). Furthermore, there was a trend for children with DCD to have shorter strides (p=0.052, ES=0.499) and a longer stance period than the TD controls (p=0.06, ES=0.729). These differences may have implications for the economy of running and subsequently the planning of targeted intervention programs to improve running gait in children with DCD.

Foot drop splints improve proximal as well as distal leg control during gait in Charcot‐Marie‐Tooth Disease

During walking, people with Charcot-Marie-Tooth (CMT) disease may compensate for distal weakness by using proximal muscles. We investigated the effect of different AFOs on distal leg control and proximal compensatory actions. Fourteen people with CMT were tested while wearing 3 types of ankle-foot orthosis (AFO) bilaterally compared with shoes alone. Walking was assessed using three-dimensional gait analysis. Stiffness of the splints was measured by applying controlled 5-degree ankle stretches using a motor. The results showed that each AFO significantly stiffened the ankle and increased ankle dorsiflexion at foot clearance compared with shoes alone. At push off, peak ankle power generation was reduced, but only with 1 type of AFO. A significant decrease in hip flexion amplitude during the swing phase was observed with all 3 AFOs. These results indicate that AFOs reduce foot drop and remove the need for some proximal compensatory action.

Patients with peripheral arterial disease exhibit reduced joint powers compared to velocity-matched controls

Previous studies have shown major deficits in gait for individuals with peripheral arterial disease before and after the onset of pain. However, these studies did not have subjects ambulate at similar velocities and potential exists that the differences in joint powers may have been due to differences in walking velocity. The purpose of this study was to examine the joint moments and powers of peripheral arterial disease limbs for subjects walking at similar self-selected walking velocities as healthy controls prior to onset of any symptoms. Results revealed peripheral arterial disease patients have reduced peak hip power absorption in midstance (p=0.017), reduced peak knee power absorption in early and late stance (p=0.037 and p=0.020 respectively), and reduced peak ankle power generation in late stance (p=0.021). This study reveals that the gait of patients with peripheral arterial disease walking prior to the onset of any leg symptoms is characterized by failure of specific and identifiable muscle groups needed to perform normal walking and that these gait deficits are independent of reduced gait velocity.

Stair ascent kinematics and kinetics with a powered lower leg system following transtibial amputation

During stair ascent (STA) persons with transtibial amputation (TTA) typically adopt a hip strategy to compensate for the limited ankle motion and joint power that is characteristic of conventional energy storing and returning (ESR) prosthetic feet. The purpose of this investigation was to determine if providing ankle power via a powered prosthetic device (BiOM) normalized STA kinematics and kinetics. Eleven individuals with TTA participated in two STA gait analysis sessions: (1) using an ESR foot, and (2) using the BiOM. Eleven height and weight matched able-bodied controls (CONT) were also assessed. Lower extremity peak kinematic and kinetic values were calculated at a self-selected and controlled cadence (80steps/min). Increased prosthetic limb peak ankle plantarflexion and push-up power were observed while using the BiOM as compared to ESR. Peak ankle power was not significantly different between BiOM and CONT indicating normalization of ankle power generation. However, peak ankle plantarflexion was significantly lower than CONT. Limb asymmetries including greater prosthetic limb hip flexion and power during stance, and decreased prosthetic limb knee power during stance were observed in the BiOM and ESR conditions. The results suggest that the BiOM successfully increased ankle motion and restored ankle power during STA. These differences did not, however, reduce the use of a hip strategy while ascending stairs. Additional device specific training may be necessary to utilize the full benefits of the device.

Effectiveness of AFO orthoses in children affected by cerebral palsy: Clinical evaluation does not always define patient satisfaction

alking. Healthy young subject were asked to mimic voluntarily nterior pelvic tilt during gait analysis sessions. Materials andmethods: Six healthy young adults (29±3 years ld) performed a gait analysis along a 12 meters walkway bareoot. After that, they were asked to mimic anterior pelvic tilt, Fig . Data were collected with Vicon Mx system with 8 cameras, two MTIOR6-5 forceplatformsandWave surfaceEMGsystem. Spatioemporal parameters, kinematic, kinetic and surface EMG of four ait cycles were analyzed, comparing self placed barefoot gait with oluntary anterior pelvic tilt one. Digital video acquisitions were lso performed. Results: Videoobservation:duringvoluntary anteriorpelvic tilt, he trunk tilted forward, the upper limbs tilted backward, the foot ontact was flat or on toe, Fig. 1. Kinematic: in comparison with barefoot gait the main diferences were the ankle plantar-flexion at foot contact, the nticipation of ankle plantar-flexion during late stance, a reduced aximum of knee flexion during swing, an increased hip flexion nd, of course, the requested increased anterior pelvic tilt. Kinetic: double bump and reduction of ankle dorsal-flexion oment, increased ankle power absorption and generation during arly stance, and reduced ankle power generation in late stance as observed, Fig. 2. Spatio-temporal parameters: the cadence increased from 24±5.11 steps/min to 145±14.4 steps/min; the stride time ecreased from 0.96±0.040 s to 0.84±0.078 s and consequently alking speed increased from 1.34±0.11 m/s to 1.57±0.26 m/s. he other spatio-temporal variables did not differ. EMG: triceps enveloped surface EMG diagram showed anticipaion of triceps activation during voluntary tilt, Fig. 3. Discussion: Voluntary anterior pelvic tilt facilitated the forward rojection of the upper bodywith the association of a not requested oewalking like behaviour. The kinematic, kinetic, spatio-temporal nd EMG parameters showed a pattern similar with the gait of toealkers. From the results of this work it is possible to hypothesize hat anterior pelvic tilt could be considered one of the elements acilitating toe walking. The whole body biomechanical configuation contributes to the aetiology of gait strategies. The selected daptive solution for balancing thepelvis could constrain alsodistal egments configurations.

Ankle and midfoot kinetics during normal gait: A multi-segment approach

Multi-segment foot models are increasingly being used to evaluate intra and inter-segment foot kinematics such as the motion between the hindfoot/tibia (ankle) and the forefoot/hindfoot (midfoot) during walking. However, kinetic analysis have been mainly restricted to one-segment foot models and could be improved by considering a multi-segment approach. Therefore, the aims of this study were to (1) implement a kinetic analysis of the ankle and theoretical midfoot joints using the existing Oxford Foot Model (OFM) through a standard inverse dynamics approach using only marker, force plate and anthropometric data and (2) to compare OFM ankle joint kinetics to those output by the one-segment foot plugin-gait model (PIG). 10 healthy adolescents fitted with both the OFM and PIG markers performed barefoot comfortable speed walking trials over an instrumented walkway. The maximum ankle power generation was significantly reduced by approximately 40% through OFM calculations compared to PIG estimates (p<0.001). This result was not caused by a decrease in OFM computed joint moments, but by a reduction in the angular velocity between the tibia/hindfoot (OFM) compared to the tibia/foot (PIG) (p<0.001). Additionally, analysis revealed considerable midfoot loading. One-segment foot models overestimate ankle power, and may also overestimate the contribution of the triceps surae. A multi-segment approach may help quantify the important contribution of the midfoot ligaments and musculature to power generation. We therefore recommend the use of multi-segment foot models to estimate ankle and midfoot kinetics, especially when surgical decision-making is based on the results of three-dimensional gait analysis.

Effect of the Number of Involved Spinal Cord Segments on Gait Function in Patients with Cervical Spondylotic Myelopathy

Study DesignRetrospective.PurposeTo determine the effect of severity of cervical spondylotic myelopathy (CSM) on gait parameters according to the number of involved spinal cord segments.Overview of LiteratureAlthough there are a large number of studies on CSM, almost all studies have focused on hand function and only a few studies have examined the gait function in patients with CSM.MethodsTwenty-three patients with CSM underwent magnetic resonance imaging and gait analysis. The subjects were divided into 2 groups; group I consisted of 9 patients with a single-level stenotic lesion and group II comprised 14 patients with multi-level stenotic lesions. Gait parameters were compared between the 2 groups and the normal control group.ResultsThere was no significant difference in the Japanese Orthopaedic Association score between the 2 groups. Cadence, walking speed, stride length, and step length were decreased in group II compared to group I and normal control group. Peak ankle plantar flexion moments during the stance phase and peak knee flexion angle during the swing phase were decreased in group II. Peak ankle, knee, and hi p power generation during the stance phase were decreased in group II; in addition, the peak ankle power generation was decreased in group II than in the normal control group.ConclusionsPatients with multi-level stenotic lesions had decreased gait ability compared to that in patients with a single-level stenotic lesion. The number of involved spinal cord segments can be one cause of gait deterioration in patients with CSM. Performing a gait analysis is useful for accurate evaluation of the patient.

Coronal Plane Knee Moments Improve After Correcting External Tibial Torsion in Patients With Cerebral Palsy

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. 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. 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). 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). Correction of external tibial torsion in ambulatory patients with cerebral palsy improves the kinematic and kinetic deviations identified by gait analysis. Level IV, therapeutic series. See Guidelines for Authors for a complete description of levels of evidence.

Gait pattern in myotonic dystrophy (Steinert disease): A kinematic, kinetic and EMG evaluation using 3D gait analysis

We investigated the gait pattern of 10 patients with myotonic dystrophy (Steinert disease; 4 females, 6 males; age: 41.5+7.6years), compared to 20 healthy controls, through manual muscle test and gait analysis, in terms of kinematic, kinetic and EMG data. In most of patients (80%) distal muscle groups were weaker than proximal ones. Weakness at lower limbs was in general moderate to severe and MRC values evidenced a significant correlation between tibialis anterior and gastrocnemius medialis (R=0.91). An overall observation of gait pattern in patients when compared to controls showed that most spatio-temporal parameters (velocity, step length and cadence) were significantly different. As concerns kinematics, patients' pelvic tilt was globally in a higher position than control group, with reduced hip extension ability in stance phase and limited range of motion; 60% of the limbs revealed knee hyperextension during midstance and ankle joints showed a quite physiological position at initial contact and higher dorsiflexion during stance phase if compared to healthy individuals. Kinetic plots evidenced higher hip power during loading response and lower ankle power generation in terminal stance. The main EMG abnormalities were seen in tibialis anterior and gastrocnemius medialis muscles.In this study gait analysis gives objective and quantitative information about the gait pattern and the deviations due to the muscular situation of these patients; these results are important from a clinical point of view and suggest that rehabilitation programs for them should take these findings into account.

The Effects of Femoral Derotation Osteotomy in Cerebral Palsy: A Kinematic and Kinetic Study

We attempted to quantify the effects of isolated femoral derotation osteotomies using clinical evaluation and gait analysis (kinematics and kinetics) in patients with cerebral palsy (CP). Twelve children with CP were evaluated before and 10 months after isolated femoral derotation osteotomy, and 15 healthy children were evaluated as controls. There were significant improvements on clinical examination. A better position of the hip and ankle in the transverse plane was evident and significant changes occurred in terms of hip and ankle kinetics after surgery. Improvements in kinematics and hip and ankle power are very important biomechanically. The correction of lever arm dysfunction and more physiological hip and ankle power generation result in an improvement in terms of energy consumption, leading to a more functional and economic gait pattern.