Alzheimer’s disease (AD) is a common and serious form of elderly dementia, but early detection and treatment of mild cognitive impairment can help slow down the progression of dementia. Recent studies have shown that there is a relationship between overall cognitive function and motor function and gait abnormalities. We recruited 302 cases from the Rehabilitation Hospital Affiliated to National Rehabilitation Aids Research Center and included 193 of them according to the screening criteria, including 137 patients with MCI and 56 healthy controls (HC). The gait parameters of the participants were collected during performing single-task (free walking) and dual-task (counting backwards from 100) using a wearable device. By taking gait parameters such as gait cycle, kinematics parameters, time-space parameters as the focus of the study, using recursive feature elimination (RFE) to select important features, and taking the subject’s MoCA score as the response variable, a machine learning model based on quantitative evaluation of cognitive level of gait features was established. The results showed that temporal and spatial parameters of toe-off and heel strike had important clinical significance as markers to evaluate cognitive level, indicating important clinical application value in preventing or delaying the occurrence of AD in the future.
ObjectiveTo explore the gait trajectory characteristics of patients after total knee arthroplasty (TKA) assisted by three-dimensional (3D) printing navigation template.MethodsTwenty female patients (20 knees) with knee osteoarthritis who were treated with TKA assisted by 3D printing navigation template between February 2017 and February 2018 were selected as the 3D printing group. The patients were 50-69 years old, with an average age of 57.2 years. The disease duration was 4-7 years, with an average of 5.6 years. The osteoarthritis was classified as Kellgren-Lawrence Ⅲ level in 5 cases and Ⅳ level in 15 cases. The preoperative hip-knee-ankle angle (HKA) was (170.8±5.6)°. All patients were varus deformity. According to age and affected side, 20 healthy female volunteers were selected as the control group. The volunteers were 51-70 years old, with an average age of 56.7 years. Preoperative HKA was (178.8±0.6)°. There was significant difference in HKA between the two groups (P>0.05). The HKA, Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and visual analogue scale (VAS) scores of the 3D printing group before and after operation were compared. At 6 months after operation, the gait trajectory characteristics of 3D printing group and control group were analyzed by Vicon gait capture system. The kinematics parameters included velocity, cadence, stride length, maximum knee flexion angle (stance), minimum knee flexion angle (stance), maximum knee flexion angle (swing), mean hip rotation angle (stance), mean ankle rotation angle (stance).ResultsThe incisions of 3D printing group healed by first intention, with no complications. All patients were followed up 7-12 months (mean, 9.0 months). The WOMAC and VAS scores at 6 months after operation were significant lower than those before operation (P<0.05). The HKA was (178.8±0.8)° at 4 weeks after operation and the difference was significant when compared with that before operation (t=39.203, P=0.000). The position of the prosthesis was good. The femoral posterior condyle osteotomy line, surgical transepicondylar axis, and patella transverse line were parallel, varus deformity was corrected, and lower limb alignment was restored to neutral position. Gait analysis at 6 months after operation showed that the differences in all kinematics parameters between the two groups were significant (P<0.05).ConclusionAssisted by 3D printing navigation template, TKA can alleviate pain symptoms and correct deformity, with satisfactory early effectiveness. Compared with healthy people, the early postoperative gait of the patients were characterized by decreasing velocity, cadence, stride length, knee flexion range, and increasing compensatory hip and ankle rotation range.
ObjectiveTo provides an objective tool to evaluate rotator cuff function in rats. MethodsSixty adult male Sprague Dawley rats, weighing (281.21± 20.12) g, were involved in this experiment. Botulinum toxin A (6 U/kg) was injected into the infraspinatus of 12 rats in Botox group. Infraspinatus tendons of 12 rats in tear group were cut by microinvasive method. Infraspinatus tendons of 12 rats in sham-operation group were exposed but not cut. No any treatment was performed on the 12 rats in normal control group. One shoulder joint of each rat was selected randomly as treatment side. After 7 days, cadence, rate of stand phase, support pressure, swing speed, stand speed, and stride length of rats in those 4 groups were measured. Treatment side and contralateral side ratio of each gait parameter was caculated. If parameters of Botox group and tear group both showed significant differences compared with those of normal control group and sham-operation group, the gait parameter was brought into rating scale as an item. Each item was assigned from 1 point to 5 points according to gait parameter. The chronic rotator cuff injury model was established in 12 rats of verification group and rating scale was used to evaluate rotator cuff function each week for 8 weeks after surgery. ResultsAll gait parameters of tear group were significantly less than those of Botox group (P＜0.05), and Botox group was significantly less than sham-operation group and normal control group (P＜0.05), but no significant difference was found between sham-operation group and normal control group (P>0.05). All gait parameters were brought into rating scale as items. All items were rated from 1 point to 5 points, so the total score was 30 points and the lowest score was 6 points. Thirty points meant normal function of infraspinatus (rotator cuff function was normal), and 6 points meant complete loss of infraspinatus function (rotator cuff function was severely damaged). Rotator cuff functional scores of rats in verification group were 27.00±1.86, 23.75±2.83, 21.33±1.92, 18.17±2.37, 13.17±1.64, 11.67±2.50, 8.17±1.27, 6.50±0.67 from the 1st week to the 8th week respectively. ConclusionThe rating scale of rat rotator cuff function may reflect the severity of rotator cuff injury and the functional status of rotator cuff to some extent in rats.
Objective To provide the objective basis for the evaluation of the operative results of vascularized greater trochanter bone flap in treating osteonecrosis of the femoral head (ONFH) by three-dimensional gait analysis. Methods Between March 2006 and March 2007, 35 patients with ONFH were treated with vascularized greater trochanter bone flap, and gait analysis was made by using three-dimensional gait analysis system before operation and at 1, 2 years afteroperation. There were 23 males and 12 females, aged 21-52 years (mean, 35.2 years), including 8 cases of steroid-induced, 7 cases of traumatic, 6 cases of alcohol ic, and 14 cases of idiopathic ONFH. The left side was involved in 15 cases, and right side in 20 cases. According to Association Research Circulation Osseous (ARCO) classification, all patients were diagnosed as having femoral-head necrosis at stage III. Preoperative Harris hip functional score (HHS) was 56.2 ± 5.6. The disease duration was 1.5-18.6 years (mean, 5.2 years). Results All incisions healed at stage I without early postoperative compl ications of deep vein thrombosis and infections of incision. Thirty-five patients were followed up 2-3 years with an average of 2.5 years. At 2 years after operation, the HHS score was 85.8 ± 4.1, showing significant difference when compared with the preoperative score (t=23.200, P=0.000). Before operation, patients showed a hip muscles gait, short gait, reduce pain gait, and the pathological gaits significantly improved at 1 year after operation. At 1 year and 2 years after operation, step frequency, pace, step length and hip flexion, hip extension, knee flexion, ankle flexion were significantly improved (P lt; 0.01). Acceleration-time curves showed that negative wave and spinous wave at acceleration-stance phase of front feet and hind feet in affected l imb were obviously reduced at 1 year and 2 years after operation. Postoperative petronas wave appeared at swing phase; the preoperative situation was three normal phase waves. Conclusion These results suggest that three-dimensional gait analysis before and after vascularized greater trochanter for ONFH can evaluate precisely hip vitodynamics variation.
【Abstract】 Objective To establ ish a three-foot weight-bearing canine model to imitate the biomechanical loading environment of the human’s hip joint. To observe and compare the kinetic changes of hind l imbs between normal and three-foot weight bearing canines. Methods Using 10 beagles, three-foot weight-bearing canine models were made by fixing unilateral wrist joints at 90º flexionally. The changes of ground reaction forces and the time of standing phases (Ts) of the hind l imbs were compared by 3-D gait analysis pre- and postoperatively. Results Canines could walk well with three l imbs after the fixation of one fore l imb. However, the gait pattern changed tremendously. The canine walked jumpily by raising its head and neck, and the bilateral hind l imbs kept contacting ground alternately. Ts of ipsilateral hind l imb was (0.48±0.04)s, and Ts of contralateral hind l imb was (0.46±0.06)s. Although, the time durations were increased a l ittle, but there were no significant differences when compared with that of normal canines (0.43±0.05)s (P gt; 0.05). The vertical ground reaction force (Fz) of ipsilateral hind l imbwas (4.63±0.85) body weight, and the Fz of contralateral hind l imb was (4.78±0.49) body weight. There were significant increases when compared with the Fz of normal canines (3.26±0.48) body weight (P lt; 0.05). The peak acceleration force of the ipsilateral hind l imb was (0.80±0.30) body weight. There was significant increase compared with that of normal canines (0.72±0.13) body weight (P lt; 0.05). The peak acceleration force of the contralateral hind l imbs was (0.68±0.22) body weight, there was no difference compared with that of normal canines (P gt; 0.05). The peak deceleration forces of the ipsilateral and contralateral hind l imbs were —(0.26±0.14) body weight and —(0.13±0.05) body weight separately. They decreased significantly when compared with that of normal canines —(0.43±0.13) body weight (P lt; 0.05). In normal canines, the upper l imbs were main load bearingl imbs, they could bear 62.8%±2.4% of body weight. However, the hind l imbs could bear only 37.2%±1.8% of body weight. On the contrary, in three-foot weight-bearing canines, the hind l imbs became the main load bearing l imbs, they could bear 59.1%±6.7% of body weight. Conclusion Three-foot weight-bearing canine model can be used as a candidate animal model to research the effects of biomechanical loading on the progression of hip joint diseases.
Objective To investigate the effect of femoral offset reconstruction on pelvic stabil ity during gait after total hip arthroplasty. Methods According to the inclusion criteria, 29 patients undergoing unilateral total hip arthroplasty between January 2000 and December 2005 were selected. There were 10 males and 19 females with an average age of 64.3 years (range, 33-75 years). The affected hips included 15 left hips and 14 right hips. The follow-up time was from 5 to 10 years (mean, 7.7 years). The Harris score was 90 to 100 (mean, 97) at last follow-up. The femoral offset ratio (FOR) was calculated by measuring the femoral offset of the bilateral hips on radiograph, and then the patients were divided into 2 groups: group A (the femoral offset of diseased hip was less than that of normal hip, n=10) and group B (the femoral offset of diseased hip was greater than that of normal hip, n=19). The pelvis kinematic variables were measured by three-dimensional gait analysis to collect the magnitude of pelvic obl ique angle (POA). Results In group A, the FOR was 0.81 ± 0.08 and the POA was (—0.42 ± 0.91)°. In group B, the FOR was 1.27 ± 0.15 and the POA was (1.02 ± 0.94)°. For the normal hip, the POA was (1.15 ± 0.85)°. The POA was significantly less in group A than in group B and the normal l imb (P lt; 0.05). The difference in POA had no significance between group B and the normal hip (P gt; 0.05). The POA was positive relative with FOR (r=0.534, P=0.003), and the regression equation was y= — 2.551+ 2.781x. Conclusion The femoral offset reconstruction is crucial to improve hip abductor function and gait.
Turning gait is very common in daily lives. However, study of turning is still limited. For researching the differences of the walking characteristics between straight gait and turning gait and between different turning strategies, and for analyzing the endopathic factor, this study selected 10 healthy young men to perform straight walking and 90° turning using two turning strategies (outside leg turning and inside leg turning). The Vicon capture system and plantar pressure capture system were used to measure gait parameters and plantar pressure parameters at the same time. The study showed that stride velocity reduced while stride time and proportion of stance time increased when turning was compared to straight walking. Inside leg turning strategy needed stronger muscle controlling and could promote turning, while outside leg turning strategy was more stable. This results will offer data for projecting gait of biped robot and provide reference value for walking rehabilitation training design and development of walking assistive equipments, etc.
Aiming at comparing the pre-operative and post-operative gait characteristics and therefore establishing post-operative rehabilitation guidance for patients with end-stage knee osteoarthritis (KOA) merged with varus deformity, this study captured the level walking and sit-to-stand trials of 9 patients with 3-dimensional motion analysis system and after which musculoskeletal multi-body dynamic analysis was conducted. The study indicated that the average range of motion (ROM) of the proposed-surgical knee was 24.4°–57.6° and that of the non-surgical knee was 22.5°–71.5°. The knee ROM of control group during level walking was 7.2°–62.4°. When the unilateral KOA patients stood up from chair to complete the sit-to-stand movement, the ground reaction forces (GRFs) symmetry was 0.72–0.85, which means that the non-surgical limb bear the majority of body weight. The GRFs of the bilateral KOA patients were smallest during the sit-to-stand movement. The strategy that the non-surgical limb dominates in loading bearing taken by the unilateral KOA patients to cover most post-operative daily activities could increase the risk of KOA among non-surgical side joints as a result of long-term excessive loading-bearing. The study, on kinematics and biomechanical characteristics of patients with KOA merged with varus deformity, could help to understand the pathogenesis of KOA merged with varus deformity from the perspective of biomechanics and to provide strong clinic guidance for the pre-operative evaluation, prevention and post-operative recovery for patients.
This paper presents a wearable exoskeleton robot system to realize walking assist function, which oriented toward the patients or the elderly with the mild impairment of leg movement function, due to illness or natural aging. It reduces the loads of hip, knee, ankle and leg muscles during walking by way of weight support. In consideration of the characteristics of the psychological demands and the disease, unlike the weight loss system in the fixed or followed rehabilitation robot, the structure of the proposed exoskeleton robot is artistic, lightweight and portable. The exoskeleton system analyzes the user's gait real-timely by the plantar pressure sensors to divide gait phases, and present different control strategies for each gait phase. The pressure sensors in the seat of the exoskeleton system provide real-time monitoring of the support efforts. And the drive control uses proportion-integral-derivative (PID) control technology for torque control. The total weight of the robot system is about 12.5 kg. The average of the auxiliary support is about 10 kg during standing, and it is about 3 kg during walking. The system showed, in the experiments, a certain effect of weight support, and reduction of the pressure on the lower limbs to walk and stand.
ObjectiveTo explore the gait trajectory characteristics and effectiveness after unicompartmental knee arthroplasty (UKA).MethodsThirty patients (30 knees) with anterior medial compartment osteoarthritis who were treated with UKA between January 2017 and December 2018 were selected as subjects (UKA group). According to age, gender, and side, 30 patients (30 knees) with knee osteoarthritis treated with total knee arthroplasty (TKA) were selected as control (TKA group). In addition to the range of motion (ROM) before operation showing significant difference between the two groups (t=4.25, P=0.00), there was no significant difference in gender, age, disease duration, sides, body mass index, and preoperative hip-knee-ankle angle (HKA), Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score between the two groups (P>0.05). The incision length, drainage volume within 24 hours after operation, and the changes of hemoglobin and albumin were recorded. The WOMAC score, ROM, and HKA before and after operation were compared between the two groups. At 1 year after operation, the gait trajectory characteristics of two groups were analyzed by Vicon three-dimensional gait capture system, and the absolute symmetry index (ASI) of the lower limbs of the two groups was calculated.ResultsThe incisions of the two groups healed by first intention, with no complications. The incision length, drainage volume within 24 hours, and the changes of hemoglobin and albumin after operation in the UKA group were significantly smaller than those in the control group (P<0.05). All patients were followed up completely, the follow-up time ranged from 13 to 20 months of UKA group (mean, 18 months) and 16 to 24 months of control group (mean, 20 months). The imaging review showed that the lower limb alignment of the two groups were restored to a neutral position, and the position of prosthesis was good. At 1 year after operation, the WOMAC score, HKA, and ROM of two groups were significantly improved when compared with those before operation (P<0.05); the postoperative WOMAC score and ROM of the UKA group were significantly better than those of the control group (P<0.05), and there was no significant difference in HKA between the two groups (t=1.54, P=0.13). Gait analysis at 1 year after operation showed that the walking speed, stride length, knee extension at mid-stance, and flexion at swing in the UKA group were significantly better than those in the TKA group (P<0.05); there was no significant difference in cadence, knee flexion at initial contact, and knee flexion at loading response between the two groups (P>0.05). The ASI of bilateral knee flexion in the UKA group was significantly greater than that in the TKA group during the initial contact and loading response period (P<0.05).ConclusionCompared with TKA, UKA has the advantages of small incision, less blood loss, and quicker functional recovery. The early gait after UKA is mainly manifested as the increase in walking speed, stride length, knee flexion at swing, and extension at mid-stance phase. From the analysis of gait symmetry, during the initial contact and loading response phase, the operation side after UKA undertakes more shock absorption and joint stabilization functions than the contralateral side.