Factors Influencing the Improvement of Gait Ability After Total Hip Arthroplasty

We aimed to investigate the factors influencing gait improvement in the patients who had undergone total hip arthroplasty. We performed gait analysis on 43 female patients with unilateral hip osteoarthritis. All the patients were analyzed before and at 2, 6, and 12 months after the surgery. There were significant reductions in spatiotemporal parameters in the patients with hip osteoarthritis compared with the control group. The mean values of the spatiotemporal parameters of the patients showed considerable improvement by 12 months after surgery; however, they did not reach the same values as those observed in the healthy subjects. The stage of osteoarthritis and the changes in the leg-length discrepancies were the factors that most influenced gait improvement after total hip arthroplasty throughout the follow-up period.     

Changes in Mediolateral Postural Control Mechanisms During Gait After Total Knee Arthroplasty

BackgroundPatients who have total knee arthroplasty (TKA) likely suffer from decreased postural stability because of postoperative changes in musculoskeletal structure and loss of proprioception. The purpose of this experimental biomechanical study was to determine if patients who have TKA improve their dynamic postural control during walking after TKA as compared with before TKA. The secondary purpose was to assess changes in postural control between post-TKA patients and healthy controls.MethodsTwenty-three patients who had primary knee osteoarthritis scheduled to undergo unilateral or bilateral TKA were prospectively enrolled. Each patient was tested at 3 months, 6 months, and 12 months after TKA. Ten healthy controls matched for age, sex, and body mass index were selected from a database of previous healthy volunteers without knee osteoarthritis. Ten Vicon cameras and four AMTI force platforms were used to collect the marker and center of pressure (COP) data while participants performed gait.ResultsInitial improvement in the double stance ratio was found by 6 months after TKA compared with before TKA. Patients showed improved postural control as evidenced by a faster mediolateral COP velocity and decreased double stance ratio at 12-month post-TKA compared with pre-TKA (P < .05). However, patients who underwent TKA exhibited limited ability to maintain consistent COP movement during walking with increased variability in COP parameters as compared with controls (P < .05).ConclusionPatients exhibited improvement in dynamic postural control after TKA with time, but had higher variability in COP parameters during gait than controls. It is possible that therapy aimed to improve proprioceptive balance after TKA may improve dynamic postural control.     

No functional impairment after Robodoc total hip arthroplasty

The Robodoc total hip replacement procedure requires a wider exposure of the proximal femur, especially of the greater trochanter, than the standard procedure. Moreover, the leg must be placed in a rigid leg-holder apparatus to obtain fixation in maximal hip adduction and external rotation. This may impair the hip abductors and reduce hip abduction in the mid- and terminal stance phase of the cycle. In this study we compared patients after Robodoc and conventional total hip arthroplasty with three-dimensional gait analysis (VICON System, Oxford Metrics, Oxford, U.K.) to assess the kinematics of the pelvis and hip. 25 patients underwent total hip replacement by means of the Robodoc total hip arthroplasty system, 25 patients were treated with conventional total hip replacement, and 40 healthy volunteers served as controls. None of the patients undergoing total hip replacement, robotic or conventional, obtained normal kinematic gait patterns 6 months after surgery. However, the reduction in hip abduction did not differ significantly in patients undergoing robotic or conventional total hip arthroplasty, which suggests that the robotic procedure did not impair hip abductor function more than the conventional method. n     

No functional impairment after Robodoc total hip arthroplasty: gait analysis in 25 patients

The Robodoc total hip replacement procedure requires a wider exposure of the proximal femur, especially of the greater trochanter, than the standard procedure. Moreover, the leg must be placed in a rigid leg-holder apparatus to obtain fixation in maximal hip adduction and external rotation. This may impair the hip abductors and reduce hip abduction in the mid- and terminal stance phase of the cycle. In this study we compared patients after Robodoc and conventional total hip arthroplasty with three-dimensional gait analysis (VICON System, Oxford Metrics, Oxford, U.K.) to assess the kinematics of the pelvis and hip. 25 patients underwent total hip replacement by means of the Robodoc total hip arthroplasty system, 25 patients were treated with conventional total hip replacement, and 40 healthy volunteers served as controls. None of the patients undergoing total hip replacement, robotic or conventional, obtained normal kinematic gait patterns 6 months after surgery. However, the reduction in hip abduction did not differ significantly in patients undergoing robotic or conventional total hip arthroplasty, which suggests that the robotic procedure did not impair hip abductor function more than the conventional method.     

Clinical study of arthroplasties for osteoarthritic hip by quantitative gait analysis: Comparison of total hip arthroplasty and bipolar endoprosthetic arthroplasty

The present study was undertaken to serially observe the gait of patients after hip arthroplasty, using quantitative gait analysis, and to compare the gait in patients after total hip arthroplasty (THA) with the gait in patients after bipolar endoprosthetic arthroplasty (BEA). The subjects were 53 women with unilateral osteoarthritis of the hip. Thirty-one (mean age, 59.5 years) of them underwent THA and 22 (mean age, 58.0 years) underwent BEA. The stance time and characteristic parameters calculated from the vertical component of the floor reaction force (FRF) were analyzed via the use of a FRF plate. The stance time, which indirectly represents the walking speed, decreased for 1 year after THA and for 3 years after BEA. The decrease in this parameter was greater on the unaffected side than on the affected side. The deceleration effect and the weighing-off effect are useful indicators for the observation of gait recovery. Significant differences in these indicators between the unaffected and affected sides were seen for 1 year after THA and for 3 years after BEA. These findings indicate that the cadence and balance of the gait recovers earlier after THA than after BEA.A summary of this paper was presented at the 21st Annual Meeting of the Japanese Society for Clinical Biomechanics and Related Research and at the 67th Annual Meeting of the Japanese Orthopaedic Association.     

Quantitative gait analysis of patients with bilateral hip osteoarthritis excluding the influence of walking speed

Background The purpose of this study was to investigate gait characteristics of patients with bilateral hip osteoarthritis (BHO) independent of walking speed. Methods We measured gait parameters in 12 BHO patients during free walking activities and in 12 normal adults during both free walking and slow walking activities using a three-dimensional computerized gait analysis system. Results Patients with BHO had a lower walking speed, step length, and cadence than normal subjects during free walking. When compared with normal subjects walking at a slow speed, the walking speed difference among BHO patients disappeared, although BHO patients retained a relatively high cadence. Kinematic and kinetic factor analysis of BHO patients at free speed compared to normal subjects walking at a slow speed showed a forward-tilted pelvic angle in the BHO patients that dropped to that of the ipsilateral side during the stance phase. The peak extension and abduction angle of the hip and the peak abduction moment of the hip were all low, whereas the peak generation power of the ankle was high in BHO patients. Conclusions Gait characteristics of patients with BHO, independent of walking speed, were as follows: (1) increased cadence and ankle generation power; (2) reduced step width, hip extension, and abduction angle as well as a lower hip abduction moment; (3) maintained forward tilting of the pelvis during gait cycle; and (4) appearance of a dropped pelvis during the stance phase.     

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     

The influence of walking speed on kinetic and kinematic parameters in patients with osteoarthritis of the hip using a force-instrumented treadmill and standardised gait speeds

BACKGROUND: It is difficult to identify objective parameters for assessing the joint function when dealing with the evaluation of orthopaedic procedures, especially endoprosthetic hip replacement. Clinical gait analysis enables parameters of force and movement to be quantified. However, the influence of gait speed on these parameters has hardly been taken into consideration so far. The objective of the present study was therefore to investigate the effect of gait speed on gait parameters and to simplify the clinical conditions in patients with osteoarthritis of the hip by determining a standardised gait speed. METHODS: A total of 28 patients with severe unilateral osteoarthritis of the hip were investigated at different gait speeds. The gait analysis equipment used consisted of an infinitely adjustable treadmill with force plates and an infrared video system. A special control mechanism permitted adjustment of the treadmill speed to a patient's self-determined pace. RESULTS: The mean gait speed of all patients with osteoarthritis of the hip was set at 2.20 km/h (0.61 m/s). Eight of the 10 gait parameters assessed increased significantly with changing gait speed. Pathological changes in gait patterns were found at the three gait speeds investigated, with the changes more accentuated at higher speeds. CONCLUSIONS: Dependence of gait parameters on gait speed could be concluded for a group of patients and for control subjects. Use of a force-instrumented treadmill is necessary for the setting of a standard gait speed, which should be set as high as achievable by patients without inducing pain and problems of coordination or balance. With the usage of standardised speeds, clinical gait analysis becomes easier to perform. Furthermore, one can assess the expected biomechanical advantages of newer prostheses, thus providing the surgeon with a basis for further decisions.     

A prospective functional outcome and motion analysis evaluation of the hip abductors after femur fracture and antegrade nailing

OBJECTIVE: To determine if dynamic hip abductor weakness during gait, evaluated through component measures of hip kinematics and hip kinetics, demonstrate longitudinal improvement after antegrade intramedullary nailing of femoral shaft fractures and if these improvements correlate with patient reported functional outcomes. DESIGN: Prospective patient protocol. SETTING: University-based, level I trauma center. PATIENTS: Eight nonconsecutive, isolated femur fracture patients. INTERVENTION: Antegrade intramedullary nailing of isolated femoral shaft fractures. MAIN OUTCOME MEASURE: Hip kinematics (hip abduction angle and ipsilateral lateral trunk lean), hip kinetics (hip abductor moment), and patient-reported functional outcome measures (Short Form-Musculoskeletal Function Assessment Survey) were assessed at 2 time points [Time1=independent ambulation without ambulatory aide, 2.0 (+/-0.6) months; Time2=approximately 6 months after injury with clinical and radiographic fracture healing, 7.2 (+/-1.5) months]. RESULTS: After surgical fixation of a femoral shaft fracture, subjects demonstrated significant time-dependent, negative effects on gait secondary to dynamic hip abductor weakness measured in terms of hip kinematics [hip abduction angle (P=0.012) and lateral trunk lean (P=0.046)] and hip kinetics [hip abductor moment (P=0.029 at loading response; P=0.022 at terminal stance)]. A significant improvement in the dysfunction index was found between the early and late assessments (21.3+/-15.0, 6.5+/-8.9, P=0.008). At late assessment of functional outcome (22.5+/-3.7 months), a significant correlation was observed between the dysfunction index and hip kinematics (ipsilateral trunk lean) at both Time1 (R=-0.811, P=0.015) and Time2 (R=-0.713, P=0.047). CONCLUSIONS: After isolated femur fracture, patients treated with antegrade intramedullary nailing demonstrated a significant negative effect on hip kinematics and kinetics, and this effect was time-dependent. Early postsurgical ipsilateral trunk lean correlated with long-term functional outcome scores; therefore, excessive frontal plane movement during gait in the early postoperative stages may be indicative of a poorer self-reported longer-term functional outcome.     

Knee biomechanics early after knee replacement surgery predict abnormal gait patterns 12 months postoperatively

An abnormal flexor moment pattern is often evident following total knee replacement (TKR) surgery. We investigated whether such a pattern at 12 months post-surgery could be predicted using biomechanical gait measures assessed before surgery and at 4 months post-surgery. Thirty two TKR patients were evaluated and classified as normal (biphasic pattern) or abnormal (flexor moment pattern) at each time point. Biomechanical parameters collected before surgery and at 4 months post-surgery were then explored for their ability to predict gait patterns at 12 months post-surgery. The gait pattern at 4 months was significantly associated with the 12 month post-surgery gait pattern, with over half of those with a flexor moment pattern at 4 months retaining this pattern at 12 months. Discriminant function analysis indicated that peak knee flexion during early stance, peak knee extension, and peak knee extension moment at 4 months post-surgery were independent predictors of the gait pattern at 12 months. Thus, an abnormal knee flexor moment pattern at 12 months post-surgery can be predicted by biomechanical analysis 4 months after surgery. Therefore, interventions aimed at improving active extension may need to be implemented early after surgery to restore a normal gait pattern.     

Objective measures of gait following revision hip arthroplasty. First medium-term results 2.6 years after surgery

AIM: The purpose of the study was to identify the functional impairments after revision arthroplasty by gait analysis. METHODS: This retrospective study compared 33 patients (mean age 58.5 years) who have undergone revision of an acetabular component (mean follow-up 2.6 years) with a group of normal control subjects. Gait analysis including recording of the three dimensional kinetics and kinematics was performed in all patients. Surface electromyography of seven leg and trunk muscles were registered bilaterally. The vertical ground reaction forces were determined by two force plates. These data were correlated with the Harris Hip Score, the d'Aubigné Score and the radiographic analysis (centre of rotation). RESULTS: The analysis revealed a decreased hip range of motion during gait (p < 0.0001). In the sagittal plane there was a significant decrease in the hip extension at the end of the stance phase (p < 0.0001). The control group reached a mean extension of - 7.6 degrees, the operated patients were limited by the extension deficit (+ 9.1) in step length (p < 0.0016) and velocity (p < 0.0001). Kinetic parameters indicated a reduced hip abductor moment (p < 0.0001). Compensation of gait instability was observed in an extended stance phase (p = 0.0389). The hip muscle activity was increased to stabilize the impaired hip. The changed kinematic parameters are observed with secondary impairments in knee extension and reduced dorsiflexion in ankle motion (p < 0.0001). Neither the Harris Hip score (77.8 points) nor the d'Aubigné score (14.9 points) were associated with the motion analysis (p > 0.05). Deterioration in kinematics are indicated by cranialisation of the centre of rotation (p = 0.18). However, medial movement of the centre of rotation does not influence the kinematic data (p > 0.05). CONCLUSION:Despite sufficient satisfactory clinical data the gait analysis confirmed objective impairments of the operated hip and neighboring joints. Gait instability is revealed in a decreased hip extension and deficient hip abduction.     

Gait compensations in patients with osteoarthritis of the hip and their relationship to pain and passive hip motion

This study related mechanisms of gait compensations to the level of pain and to limitations in passive motion in patients with osteoarthritis of the hip. Joint motion, moments, and intersegmental forces were calculated for 19 patients with unilateral osteoarthritis of the hip (12 men and seven women) and for a group of normal subjects (12 men and seven women) with a similar age distribution. The patients who had osteoarthritis walked with a decreased dynamic range of motion (17 ± 4°) of the hip and with a hesitation or reversal in the direction of the sagittal plane motion as they extended the hip. The patients with a hesitation or reversal in motion had a greater loss in the range of motion of the hip during gait (p < 0.004) and a greater passive flexion contracture (p < 0.022) than those with a smooth pattern of hip motion. This alteration in the pattern of motion was interpreted as a mechanism to increase effective extension of the hip during stance through increased anterior pelvic tilt and lumbar lordosis. The patients who had osteoarthritis of the hip walked with significantly decreased external extension, adduction, and internal and external rotation moments (p < 0.008). The decreased extension moment was significantly correlated with an increased level of pain (R = 0.78; p < 0.001). This finding suggests that decreasing muscle forces (hip flexors) may be one mechapism used to adapt to pain.     

Positive outcomes following gait therapy intervention for hip osteoarthritis: A longitudinal study

Footwear‐generated biomechanical manipulation of lower‐limb joints was shown to beneficially impact gait and quality of life in knee osteoarthritis patients, but has not been tested in hip osteoarthritis patients. We examined a customized gait treatment program using a biomechanical device shown in previous investigations to be capable of manipulating hip biomechanics via foot center of pressure (COP) modulation. The objective of this study was to assess the treatment program for hip osteoarthritis patients, enrolled in a 1‐year prospective investigation, by means of objective gait and spatiotemporal parameters, and subjective quality of life measures. Gait analysis and completion of questionnaires were performed at the start of the treatment (baseline), and after 3, 6, and 12 months. Outcome parameters were evaluated over time using linear mixed effects models, and association between improvement in quality of life measures and change in objective outcomes was tested using mixed effect linear regression models. Quality of life measures improved compared to baseline, accompanied by increased gait speed and cadence. Sagittal‐plane hip joint kinetics, kinematics, and spatiotemporal parameters changed throughout the study compared to baseline, in a manner suggesting improvement of gait. The most substantial improvement occurred within 3 months after treatment initiation, after which improvement approximately plateaued, but was sustained at 12 months. Speed and cadence, as well as several sagittal‐plane gait parameters, were significant predictors of improvement in quality of life. Clinical significance: Evidence suggests that a biomechanical gait therapy program improves subjective and objective outcomes measures and is a valid treatment option for hip osteoarthritis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2222–2232, 2017.

     

Short-term Recovery of Balance Control after Total Hip Arthroplasty

Hip osteoarthritis leads to chronic pain and deteriorated joint function, which affect weightbearing and balance during gait. THA effectively restores hip function but it is not known whether THA restores balance during gait. We hypothesized patients would have greater frontal plane and smaller sagittal plane center of mass-center of pressure inclination angles preoperatively compared with control subjects, and THA would improve these inclination angles by 16 weeks postsurgery. Compared with control subjects, we observed greater frontal plane inclination angles and smaller sagittal plane angles preoperatively, indicating gait imbalance. These inclination angles were improved postoperatively, providing better balance control. Despite improvement, patients differed in frontal and sagittal plane inclination angles compared with control subjects. This suggests residual deficits in dynamic balance control in patients undergoing THA before and up to 4 months after surgery. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.     

Thoracic vertebral body fracture after total hip replacement in diffuse idiopathic skeletal hyperostosis

This article describes the critical clinical sequelae of a patient with diffuse idiopathic skeletal hyperostosis who sustained an acute iatrogenic thoracic vertebral body fracture with subsequent spinal cord injury after a total hip replacement, with a final lethal course.A 57-year-old woman was referred to the authors' institution after undergoing a total hip replacement in the supine position for secondary osteoarthritis. Postoperatively, the patient had symptoms of an incomplete paraplegia. Computed tomography scan and magnetic resonance imaging revealed diffuse idiopathic skeletal hyperostosis and an acute unstable fracture of T11 with spinal contusion. A posterior spinal fusion of T10-L1 with laminectomy of T11 was performed immediately on admission. Postoperatively, no improvement of the neurological deficit was observed. After developing multiorgan failure while in intensive care, the patient died 2 months after the total hip replacement.The morphological and functional symptoms of diffuse idiopathic skeletal hyperostosis with the typical ossification of the longitudinal ligaments and the associated loss of bending forces of the spine were detected postoperatively. This severe case demonstrates that the surgeon must be alert to possible complications due to intraoperative maneuvers in patients with stiffened spinal disorders undergoing total hip replacement.     

Walking ability after total hip replacement. A comparison of gait analysis in unilateral and bilateral cases.

We studied 50 patients before and after unilateral total hip replacement, and compared them, using gait analysis, with 22 having staged bilateral operations. The average age of the patients was 65 years at the first operation. The mean follow-up was 53 months for the unilateral cases and 27 months, after the second THR, for the bilateral cases. The average interval between first and second THR was 24 months. Patients with bilateral hip disease did not gain optimal function, even on the first side, until both hips had been replaced. Unilateral replacement gave better gait analysis results than did either side after bilateral procedures.     

Hip and knee replacement after longstanding hip arthrodesis

This study determined whether patients with severe knee disease below a hip arthrodesis can be treated successfully with total knee replacement alone or whether such patients require total hip arthroplasty followed by knee replacement. Eighteen patients who had hip arthrodesis for a mean of 33 years underwent total hip replacement alone, total knee replacement alone, or a combination of both. The Harris hip score improved from a mean of 55.3 to a mean of 86.9 points at 45 months after total hip arthroplasty. The Hospital for Special Surgery knee score improved from a mean of 33 to a mean of 78 points in patients who had total knee replacement after total hip arthroplasty. The Hospital for Special Surgery knee score improved from a mean of 35 to a mean of 44 points in patients having total knee replacement alone below a hip arthrodesis. The followup after total knee replacement averaged 53 months. These data suggest that a knee replacement alone in a patient with a fused hip is unlikely to provide a satisfactory result. Patients with severe knee disease below hip arthrodesis require total hip arthroplasty followed by knee replacement. This applies even when severe osteoarthritis of the knee is the primary complaint.     

Effects of intramuscular psoas lengthening on pelvic and hip motion in patients with spastic diparetic cerebral palsy

The effects of intramuscular psoas lengthening on gait in cerebral palsy patients have been the subject of debates, and the indications for such procedure are still controversial. The purpose of this study was to evaluate the effects of intramuscular psoas lengthening on sagittal plane pelvic and hip motion in patients with spastic diparetic cerebral palsy and identify the factors linked to the best possible outcome. A retrospective study was performed in 26 independent ambulatory patients. All of them had undergone an intramuscular psoas lengthening over the pelvic brim. The mean age at the time of surgery was 11.10 years, and most cases went through additional simultaneous procedures. A complete gait analysis was performed before and, on average, at 17.69 months (range, 6-39 months) after surgery. The Thomas test values, maximum hip extension in stance, and pelvic tilt were analyzed before and after surgical intervention, and the results were statistically compared. The most significant postoperative effect was the reduction of pelvic range of motion (P < 0.01). Reduction of anterior pelvic tilt was observed only in those patients with no previous need of an external aid (P < 0.01), and the studied group did not show a significant improvement of hip extension at terminal stance. According to the results, intramuscular psoas lengthening was useful in reducing pelvic range of motion at the sagittal plane, but this study also suggests that pelvic and hip disruptions of the same plane (sagittal) seem to have a multifactorial etiology. The use of external assistive devices in patients with balance problems may lead to increased anterior pelvic tilt as well as reduction of hip extension at terminal stance.     

髋关节置换术中下肢不等长的预防

目的探讨预防或减少髋关节置换术后下肢不等长的有效方法。方法选取需行髋关节置换的患者40例,随机分为实验组和对照组,每组20例。术前测量双下肢长度差异值,实验组术中使用自行设计的下肢等长测量装置,根据术前测量值调节手术侧肢体长度;对照组采用常规手术方法。术后第2天测量患者双下肢长度差异值。术后6个月通过问卷调查,对患者进行满意度调查及患髋的Harris评分。结果术后6个月两组患者均满意,但在满意程度上存在差异;实验组与对照组术后双下肢长度差异值比较,差异有统计学意义（P〈0.05）;实验组与对照组术后患髋Harris评分,差异无统计学意义（P〉0.05）。结论在髋关节置换术中使用下肢等长测量装置,可有效减少或消除髋关节置换术后双下肢不等长,提高患者的满意度。