Gait and function in patients with a femoral endoprosthesis after tumor resection: 18 patients evaluated 12 years after surgery

We performed gait analysis in 18 patients with a femoral endoprosthesis: 12 distal, 3 proximal and 3 total. Follow-up after surgery was mean 12 (0.6-19) years. The gait parameters measured were walking velocity, step length, duration of stance phase and swing phase. Goniometry of the hip, knee and ankle in both legs was determined during free-paced walking. The functional outcome score of the Musculoskeletal Tumor Society (MSTS) and the Ambulation score were also assessed in all patients. The mean free-paced walking velocity was 88% of normal. The step length of the uninvolved leg was longer than that of the involved one. The swing phase of the involved leg was longer than that of the uninvolved leg, and the stance phase of the involved leg was shorter than that of the uninvolved leg. Goniometry showed three abnormal patterns in the involved leg: a stiff knee gait in 10 patients, a flexed knee gait in 6, and an abnormal flexion-extension pattern in the hip in 9. Goniometry of the uninvolved leg was normal. The mean MSTS score was 22 points (72%). This showed a significant positive correlation to the Ambulation score, but no correlation to any of the temporal variables. Our findings indicate that the time of load on the involved leg, whether conscious or not, is reduced. Follow-up studies are needed to evaluate the effects of the asymmetrical gait pattern observed and the abnormal goniometric results on the development of endoprosthesis-related complications.     

Walking pattern in 9 women with hip dysplasia 18 months after periacetabular osteotomy

Background Periacetabular osteotomy improves radiographic predictors of osteoarthrosis and diminishes pain and functional impairment. No changes in function quantified by gait analysis have yet been documented. We evaluated the functional outcome of periacetabular osteotomy in relation to gait.

Methods The gait pattern of 9 women (median age 39 years) with hip dysplasia who were treated with unilateral periacetabular osteotomy was analyzed before periacetabular osteotomy and an average of 1.5 years afterwards. Data were collected using 5 video cameras and 2 force plates. An inverse dynamics approach was used to calculate sagittal joint angles and moments in the stance phase.

Results Postoperatively, all subjects walked with an increased extension of the knee joint during the entire stance phase compared to the preoperative movement pattern.

Interpretation The subjects achieved a more upright walking pattern but continued to relieve the hip joint by maintaining a reduced flexor moment.     

Gait analysis of spastic walking in patients with cervical compressive myelopathy

To assess neurological status and to evaluate the effect of surgical decompression in patients with cervical myelopathy, we performed computerized gait analysis in 24 patients with cervical compressive myelopathy who showed spastic walking. Gait analysis was repeated during neurological follow-up that averaged 32.4 months. The gait pattern in patients with severe myelopathy was characterized by hyperextension of the knee in the stance phase without plantar flexion of the ankle in the swing phase, significantly reduced walking speed and step length, prolonged stance phase duration and decreased single-stance phase duration, and increased step width. The angle of flexion of the knee joint in the stance phase was significantly correlated with the Japanese Orthopaedic Association (JOA) score. Postoperative neurological improvement was associated with increased walking speed and decreased extension angle of the knee joint (single-stance phase and swing phase). Postoperatively, 12 patients had normalized extension of the knee in stance phase and their walking speed, cadence, stance phase duration, and single-stance phase duration, as well as step length and width, showed nonsignificant differences from these parameters in healthy controls. Our results show that kinesiological gait analysis is clinically useful for the functional assessment of the severity of spastic walking in cervical myelopathy.     

Electromyographic and gait analysis of forty-three patients after rotationplasty

BACKGROUND: Rotationplasty is considered to be a treatment option for patients who have had a primary malignant bone tumor of the distal part of the femur or the proximal part of the tibia. The present study was performed to evaluate the muscle activity, the kinetics (range of motion of the hip and knee joints), and the kinematics (joint moments) after rotationplasty and to determine whether there was an association between these parameters and the functional outcome. METHODS: Forty-three patients who had been managed with rotationplasty for the treatment of a femoral or tibial bone tumor were evaluated clinically and functionally. The mean age (and standard deviation) at the time of follow-up was 24.4 +/- 10.7 years (range, eight to sixty-eight years), the mean age at the time of the procedure was 17.8 +/- 10.2 years (range, seven to sixty-three years), and the mean duration of follow-up was 6.7 +/- 4.9 years (range, 0.7 to eighteen years). Instrumented gait and electromyographic analyses were performed. The qualitative data were compared with the functional outcome, which was determined with the functional evaluation score of the Musculoskeletal Tumor Society. RESULTS: Gait analysis revealed a fairly normal walking pattern with a slight limp and a lateral lean of the trunk over the ipsilateral limb that led to a reduced joint moment in the hip (moment on involved side, 68 percent [compared with a control group]; moment on uninvolved side, 81 percent). The ranges of motion of the hips (uninvolved side, 42.0 +/- 8.2 degrees; involved side, 42.4 +/- 8.0 degrees) and the knees (uninvolved side, 59.7 +/- 5.0 degrees; involved side [former ankle joint], 58.1 +/- 11.6 degrees) were symmetrical even though the knee-motion pattern of the involved limb indicated a slightly reduced extensor mechanism in 51 percent (twenty-two) and a markedly reduced extensor mechanism in 35 percent (fifteen) of the forty-three patients. Electromyography revealed function of the muscles of the involved limb, with comparable amplitudes in the involved and uninvolved limbs. The leg muscles of the involved limb were active in the stance phase (the soleus and the lateral and medial heads of the gastrocnemius) and the swing phase (the peroneus longus and the tibialis anterior) according to their function in relation to the new knee joint. The patients had a good functional result, with a mean score of 23.9 +/- 2.7 of 30 points. With the numbers available for study, we could not show the duration of follow-up to be related to the overall outcome, but the age at the time of the operation was related to the total functional score as well as to gait and walking ability (p < 0.05). CONCLUSIONS: The results of the electromyographic and gait analyses demonstrated good functional restoration of gait following rotationplasty.     

Further Development of Hybrid Functional Electrical Stimulation Orthoses

Abstract: In this study two aspects of hybrid functional electrical stimulation (FES) orthoses were investigated: joint motion constraints and FES control strategies. First, the effects of joint motion constraints on the gait of normal subjects were investigated using modern motion analysis systems, including electromyogram (EMG) and heart rate measurements. An orthosis was developed to impose joint motion constraints; the knee and ankle could be fixed or free, and the hip joint could rotate independently or coupled, according to a preset flexion-extension coupling ratio (FECR). Compared with a 1:1 hip FECR, a 2:1 hip FECR was associated with a reduced energy cost and increased speed and step length. The knee flexion during swing significantly reduced energy cost and increased walking speed. Ankle plantar flexion reduced the knee flexing moment during the early stance phase. Second, trials on 3 paraplegic subjects were conducted to implement some of these findings. It appeared that the 2:1 FECR encouraged hip flexion and made leg swing easier. A simple FES strategy increased walking speed and step length and reduced crutch force impulse using fixed orthotic joints.     

Surgical treatment of knee dysfunction in cerebral palsy

The prerequisites for normal gait are: (1) stability in the stance phase of gait, (2) clearance of the foot in the swing phase, (3) proper foot preposition in swing, and (4) an adequate step length. In the stance phase, the knee provides shock absorption and energy conservation; in the swing phase, it allows foot clearance. To accomplish these functions, the knee must extend fully in stance and flex approximately 60 degrees in swing. Consequently, balanced muscle action at the hip, knee, and ankle joints, combined with adequate acceleration from the hip flexor and triceps surae muscles, is essential. In the crouch gait of spastic cerebral palsy, hamstring lengthening alone often converts the flexed-knee gait to an extended-knee, stiff-legged gait with inadequate swing-phase knee flexion. This unwanted conversion is due to cospasticity of the quadriceps and hamstring muscles. Restoration of normal knee function in patients with spastic paralysis is more successful when fractional hamstring lengthening is combined with a transfer of the distal rectus femoris tendon to either the iliotibial band or the distal tendon of the semitendinosus.     

全身关节过度活动患者步行时膝关节步态图特征

目的研究全身关节过度活动(GJH)患者平地行走及下坡步行时膝关节步态图特征。 方法招募18～24岁健康大学生志愿者(排除膝关节外伤史等),分为全身关节过度活动组(GJH组,Beighton评分5分,21人)和正常组(49人)。采集性别、身高、体重等信息,使用国际膝关节评分(IKDC)2000、Lysholm评分等问卷调查膝关节功能,测量Beighton评分系统的指标。采用三维运动分析系统测量受试者平地行走和下坡步行时的膝关节运动学参数。 结果屈伸自由度上,平地行走时GJH组和正常组无明显差异,但在下坡步行时,在摆动相GJH组较正常组表现出更大的屈曲角度,最大屈曲角度：(67.40±5.48)°vs (62.27±6.57)°(t＝－2.961,P<0.01)。与正常组相比,在内外旋和前后位移自由度上,无论是平地行走还是下坡行走,GJH组均表现出较大的外旋角度和前向位移,平地支撑相中期12%前后位移：(0.73±0.45)mm vs(0.23±0.27)mm(t ＝－4.713,P<0.001),且在下坡行走时,外旋角度和前向位移,支撑相中期12%前后位移：(0.78±0.62)mm vs (0.20±0.36)mm(Z＝－3.873,P<0.001),增大更明显。 结论GJH患者在下坡步行时表现出更明显的步态参数的变化,以适应功能需求更高的下坡运动,可能是由膝关节周围肌肉来代偿的。针对步态参数的异常,可通过步态再训练及关节稳定性训练,以增强关节过度活动患者膝关节周围肌肉力量,从而增强膝关节的稳定性。     

The functional use of the reciprocal hip mechanism during gait for paraplegic patients walking in the Louisiana State University reciprocating gait orthosis.

Reciprocally linked orthoses used for paraplegic walking have some form of linkage between the two hip joints. It has been assumed that flexion of the swinging leg is driven by extension of the stance leg. The aims of this study were to investigate the moments generated around the hip joint by the two cables in a Louisiana State University Reciprocating Gait Orthosis (LSU-RGO). Six (6) subjects were recruited from the Regional Spinal Injuries Centre at Southport, who were experienced RGO users. The cables were fitted with strain gauged transducers to measure cable tension. Foot switches were used to divide the gait into swing and stance phases. A minimum of 20 steps were analysed for each subject. Moments about the hip joint for each phase of gait were calculated. There were no moments generated by the front cable in 4 of the subjects. In only 2 subjects did the cable generate a moment that could assist hip flexion during the swing phase. These moments were very low and at best could only have made a small contribution to limb flexion. The back cable generated moments that clearly prevented bilateral flexion. It was concluded that the front cable, as used by these experienced RGO users, did not aid flexion of the swinging limb.     

Rectus transfer in spastic diplegia

Objectives  

Change of function of the rectus femoris through medial transfer of its distal tendon. This procedure transforms a hip flexor and knee extensor into a hip and knee flexor. Thus the muscle acts as a hip flexor during the terminal stance phase and swing phase and as a knee flexor during the swing phase. This permits the foot to clear the ground and to improve the spastic gait.     

Improvement in function after valgus bracing of the knee. An analysis of gait symmetry

The use of a valgus brace can effectively relieve the symptoms of unicompartmental osteoarthritis of the knee. This study provides an objective measurement of function by analysis of gait symmetry. This was measured in 30 patients on four separate occasions: immediately before and after initial fitting and then again at three months with the brace on and off. All patients reported immediate symptomatic improvement with less pain on walking. After fitting the brace, symmetry indices of stance and the swing phase of gait showed a consistent and immediate improvement at 0 and 3 months, respectively, of 3.92% (p = 0.030) and 3.40% (p = 0.025) in the stance phase and 11.78% (p = 0.020) and 9.58% (p = 0.005) in the swing phase. This was confirmed by a significant improvement at three months in the mean Hospital for Special Surgery (HSS) knee score from 69.9 to 82.0 (p < 0.001). Thus, wearing a valgus brace gives a significant and immediate improvement in the function of patients with unicompartmental osteoarthritis of the knee, as measured by analysis of gait symmetry.     

Impulse-forces during walking are not increased in patients with knee osteoarthritis

Background Impulsive forces in the knee joint have been suspected to be a co-factor in the development and progression of knee osteoarthritis. We thus evaluated the impulsive sagittal ground reaction forces (iGRF), shock waves and lower extremity joint kinematics at heel strike during walking in knee osteoarthritis (OA) patients and compared them to those in healthy subjects.

Subjects and methods We studied 9 OA patients and 10 healthy subjects using three-dimensional gait analyses concentrated on the heel strike. Impulse GRF (iGRF) was measured together with peak accelerations (PA) at the tibial tuberosity and sacrum. Sagittal lower extremity joint angles at heel strike were extracted from the gait analyses. As OA is painful and pain might alter movement strategies, the patient group was also evaluated following pain relief by intraarticular lidocaine injections.

Results The two groups showed similar iGRF, similar tibial and sacral PA, and similar joint angles at heel strike. Following pain relief, the OA patients struck the ground with more extended hip and knee joints and lower tibial PA compared to the painful condition. Although such changes occurred after pain relief, all parameters were within their normal ranges.

Interpretation OA patients and healthy subjects show similar impulse-forces and joint kinematics at heel strike. Following pain relief in the patient group, changes in tibial PA and in hip and knee joint angles were observed but these were still within the normal range. Our findings make us question the hypothesis that impulse-forces generated at heel strike during walking contribute to progression of OA.     

Effective gait patterns for offloading the medial compartment of the knee

Gait modification offers a noninvasive option for offloading the medial compartment of the knee in patients with knee osteoarthritis. While gait modifications have been proposed based on their ability to reduce the external knee adduction moment, no gait pattern has been proven to reduce medial compartment contact force directly. This study used in vivo contact force data collected from a single subject with a force‐measuring knee replacement to evaluate the effectiveness of two gait patterns at achieving this goal. The first was a “medial thrust” gait pattern that involved medializing the knee during stance phase, while the second was a “walking pole” gait pattern that involved using bilateral walking poles commonly used for hiking. Compared to the subject's normal gait pattern, medial thrust gait produced a 16% reduction and walking pole gait a 27% reduction in medial contact force over stance phase, both of which were statistically significant based on a two‐tailed Mann–Whitney U‐test. While medial thrust gait produced little change in lateral and total contact force over the stance phase, walking pole gait produced significant 11% and 21% reductions, respectively. Medial thrust gait may allow patients with knee osteoarthritis to reduce medial contact force using a normal‐looking walking motion requiring no external equipment, while walking pole gait may allow patients with knee osteoarthritis or a knee replacement to reduce medial, lateral, and total contact force in situations where the use of walking poles is possible. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 1016–1021, 2009     

Trans-tibial amputee gait: time-distance parameters and EMG activity

Gait analysis of trans-tibial (TT) amputees discloses asymmetries in gait parameters between the amputated and sound legs. The present study aimed at outlining differences between both legs with regard to kinematic parameters and activity of the muscles controlling the knees. The gait of 14 traumatic TT amputees, walking at a mean speed of 74.96 m/min, was analysed by means of an electronic walkway, video camera, and portable electromyography system. Results showed differences in kinematic parameters. Step length, step time and swing time were significantly longer, while stance time and single support time were significantly shorter on the amputated side. A significant difference was also found between knee angle in both legs at heel strike. The biceps femoris/vastus medialis ratio in the amputated leg, during the first half of stance phase, was significantly higher when compared to the same muscle ratio in the sound leg. This difference was due to the higher activity of the biceps femoris, almost four times higher than the vastus medialis in the amputated leg. The observed differences in time-distance parameters are due to stiffness of the prosthesis ankle (the SACH foot) that impedes the normal forward advance of the amputated leg during the first half of stance. The higher knee flexion at heel strike is due to the necessary socket alignment. Unlike in the sound leg, the biceps femoris in the amputated leg reaches maximal activity during the first half of stance, cocontracting with the vastus medialis, to support body weight on the amputated leg. The obtained data can serve as a future reference for evaluating the influence of new prosthetic components on the quality of TT amputee's gait.     

腰椎间盘突出症患者步态观察与分析

运用频闪摄影计算机图象分析方法观察分析了９例腰椎间盘突出症的步态运动，并与正常人进行了对比。结果发现，患者整个步态周期延长，患肢站立相延长、摆动相相对缩短。患肢髂膝踝水平与垂直位移范围减小、速度变慢，这些变化可为评定病痛程度与治疗效果提供重要参考。     

Correlations Between Changes in Gait and in Clinical Status After Knee Arthroplasty

Twenty-six knee arthroplasties in 22 subjects were studied clinically and in a gait laboratory before and on one or more occasions after surgery. The purpose was to identify changes in gait characteristics and relate them to changes in the clinical situation of the patients.

The gait patterns of the patients changed following surgery mainly with respect to their time-distance characteristics; stride length, cadence, time of swing, and time of support. Positive correlations were noted between these gait changes and the patient's pain, his limp, and his walking distance. It is concluded that the information obtained in a sophisticated gait laboratory is of limited value to the surgeon in his clinical assessment.     

Dermatome electrical stimulation as a therapeutic ambulatory aid for incomplete spinal cord injured patients

Electrical stimulation of the L-3,4 dermatome during treadmill walking is proposed as a gait training modality in incomplete spinal cord injured patients. The dermatome stimulation proved to be efficient in diminishing the extensor tone occurring after loading of the paralyzed limb during the stance phase of walking and resulting in improved flexion of the leg during the swing phase.     

Disarticulation of the knee in children. A functional assessment

We assessed the functional abilities of six patients who had had disarticulation of nine knees during childhood by analyzing their gait using electrocardiographic telemetry. Those who were more than five years old were further studied by timing them as they ran the fifty-yard (45.7-meter) dash and by testing the strength of the musculature of the hip girdle using a Cybex dynamometer. The physiological cost-index of Butler et al. was used to assess energy consumption. Three patients had had unilateral disarticulation and three had had bilateral disarticulation. Kinematic studies showed persistent bilateral abduction of the hip throughout the gait cycle in all six patients. The flexion-extension arc of the hip was decreased in the three who had had bilateral disarticulation. Increased flexion of the hip was noted on the normal side and decreased flexion, on the affected side in those who had had unilateral disarticulation. Phase reversal of pelvic obliquity was noted in the amputees who had had bilateral disarticulation. The prosthetic knee showed good flexion during the swing phase. All patients showed a mild decrease in the velocity of gait and in the length of step and stride. The patients who had had unilateral disarticulation showed decreased duration of the bilateral stance and single stance phases and increased duration of the swing phase. Those who had had bilateral disarticulation of the knee had a normal distribution of the components of the gait cycle: bilateral stance, single stance, and swing. The physiological cost-index for all six was within the normal range, indicating minimum energy handicap.(ABSTRACT TRUNCATED AT 250 WORDS)     

Kinetic and kinematic characteristics of gait in patients with medial knee arthrosis

We compared the mechanics of gait in 13 patients with early medial arthrosis (OA) of the knee and 13 normal controls, by measuring gait events, kinematic and kinetic parameters. In the OA group, walking velocity, cadence and stride length were reduced and stride time and double support time accordingly increased on both sides, the overall stance phase was prolonged in the OA group, but the stance phase and swing phase peak flexion were reduced. The varus in the stance phase and the valgus in the swing phase were increased. The extensor moment in the loading response was increased and the flexor moment at late stance reduced in the OA group. Patients with OA had a greater valgus (abductor) and internal rotation moment during the stance phase. The times to second vertical force peak (VFP) were similar in the two groups. Values of VFP1 and VFP2 were lower in the OA group. Our findings indicate that computerized gait analysis can be used to reveal various mechanical abnormalities accompanying arthrosis of the knee joint at an early stage. Some of these abnormalities may have etiologic implications, but others may represent secondary changes developed in part as a compensatory mechanism in knee OA.     

Kinetic and kinematic characteristics of gait in patients with medial knee arthrosis

We compared the mechanics of gait in 13 patients with early medial arthrosis (OA) of the knee and 13 normal controls, by measuring gait events, kinematic and kinetic parameters. In the OA group, walking velocity, cadence and stride length were reduced and stride time and double support time accordingly increased on both sides, the overall stance phase was prolonged in the OA group, but the stance phase and swing phase peak flexion were reduced. The varus in the stance phase and the valgus in the swing phase were increased. The extensor moment in the loading response was increased and the flexor moment at late stance reduced in the OA group. Patients with OA had a greater valgus (abductor) and internal rotation moment during the stance phase. The times to second vertical force peak (VFP) were similar in the two groups. Values of VFP1 and VFP2 were lower in the OA group. Our findings indicate that computerized gait analysis can be used to reveal various mechanical abnormalities accompanying arthrosis of the knee joint at an early stage. Some of these abnormalities may have etiologic implications, but others may represent secondary changes developed in part as a compensatory mechanism in knee OA.