Adaptive patterns of movement during stair climbing in patients with knee osteoarthritis

The purpose of this study was to determine if there is a distinctive characteristic in the pattern of movement (forward trunk lean to reduce demand on the quadriceps muscle) during stair climbing in patients with knee osteoarthritis (OA) that is associated with the severity of the disease. Twenty‐three patients with radiographically diagnosed knee OA and 20 physically active adults performed stair ascending trials without support at their self‐selected speed. Standard gait analysis was used to calculate three‐dimensional lower extremity joint kinematics and kinetics. Forward trunk lean, or trunk flexion, was defined as the sagittal plane projection of the angle between a line connecting the midpoint of the trans‐acromion line and the midpoint of the trans‐iliac crest line and the global vertical axis. Patients with more severe knee OA (KL ≥ 3) had greater forward trunk lean (+6.3°, p = 0.045) and lower knee net quadriceps moments (?35.2%, p = 0.001) than controls. In more severe patients, the forward trunk lean was correlated with a reduction in the net quadriceps moment during stair climbing (R² = 0.590, p = 0.006). The results of this study identified a distinctive compensatory pattern of movement to reduce the quadriceps demand during stair climbing in patients with more severe knee OA by increasing forward trunk lean. Assessing forward trunk lean during stair climbing may be a useful functional marker for evaluating osteoarthritis status and quadriceps function that appears to be a more sensitive indicator of disease severity than perceived pain. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:325–329, 2009     

Stair dimension affects knee kinematics and kinetics in patients with good outcome after TKA similarly as in healthy subjects

Joint biomechanics during stair walking may contain important information on functional deficits in patients with orthopaedic conditions but depend on the stair dimension. The goal of this study was to compare knee kinematics and kinetics between patients with good outcome 2 years after total knee arthroplasty (TKA) and age‐matched controls during stair ascent and descent at two different stair heights. Principal component analysis was used to detect differences in gait mechanics between 15 patients and 15 controls at different stair conditions. Linear mixed models showed differences in knee kinematic and kinetic patterns (in flexion/extension and abduction/adduction) between stair heights. The knee adduction angle was more affected by stair heights in stair ascending whereas knee adduction moment and knee power were more affected during stair descent. Some stair by height and subject effects were small but not significant. Overall, good outcome after TKA is reflected in close‐to‐normal knee biomechanics during stair walking. Specific stair configuration must be considered when comparing joint biomechanics between subject groups and studies. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1753–1761, 2016.     

Functional comparison of posterior cruciate-retained versus cruciate-sacrificed total knee arthroplasty

Gait of 11 patients with bilateral paired posterior cruciate-retaining and cruciate-sacrificing total knee arthroplasties (TKA) was studied preoperatively and two years postoperatively on walking and stair climbing. Five-year clinical and roentgenographic examinations were included in the study. Differences between the two prostheses were noted both in level walking and in stair climbing. On level walking, cruciate-sacrificed TKA had more flexion in loading response and increased flexion and varus moments with increased muscle activity of quadriceps and biceps femoris. Abnormal gaits common to both types of knee were decreased flexion in stance and decreased single-limb stance. Both knees had a stiff-legged gait during stance. On stairs, the cruciate-sacrificed TKA substituted soleus muscle activity for knee stability. The single-limb stance and range of motion were similar for both knees. In clinical terms, the cruciate-sacrificed TKA is less efficient and has greater medial loading and higher joint reaction forces that may affect durability of the prosthesis. The five-year knee scores, patient satisfaction, and roentgenographic examinations were equal for both sets of knees.     

The effects of the rotating-hinge total knee replacement on gait and stair stepping.

We studied 7 younger and 5 older patients who had rotating-hinge total knee replacements, 10 patients who had semiconstrained total knee replacements, and 8 younger and 11 older healthy control subjects to determine the effects of the rotating-hinge device on gait and stair stepping. The younger patients with the rotating-hinge device had few significant differences from the younger control subjects during gait or stair stepping. The older patients with the rotating-hinge device had several significant differences from both the older control subjects and subjects with the semiconstrained device during gait and stair stepping. Nevertheless, the proportions of older patients with the 2 devices who were able to perform the step-on activity for the highest step were the same.     

A comparison of isokinetic strength testing and gait analysis in patients with posterior cruciate-retaining and substituting knee arthroplasties

Fourteen patients with a posterior-stabilized prosthesis in one knee and a posterior cruciate-retaining prosthesis in the contralateral knee and both scoring good or excellent on the Hospital for Special Surgery (HSS) knee scale were evaluated by isokinetic muscle testing and comprehensive gait analysis at a mean follow-up of 98 months after arthroplasty. The average HSS knee score (93 points) and the average Knee Society score (94 points) were the same for the cruciate-retaining and posterior-stabilized knees. No differences were noted between the cruciate-retaining and the posterior stabilized knees with respect to isokinetic muscle testing parameters (peak torque, endurance, angle of peak torque, and torque acceleration energy) for both quadriceps and hamstrings. No significant differences were found between the cruciate-retaining and the posterior-stabilized knees with regard to gait parameters, knee range of motion, and electromyographic waveforms during level walking and stair climbing. Cruciate-retaining and posterior-stabilized total knee prostheses perform equally well during level gait and stair climbing.     

Hip biomechanics during stair ascent and descent in people with and without hip osteoarthritis

Hip osteoarthritis (OA) is often associated with pain and impaired function. Understanding biomechanical alterations in patients with hip OA during challenging activities such as stair use is important to inform treatments. The aim of this study was to determine whether kinematics and kinetics during stair ambulation differed between people with hip OA and healthy controls. Fifteen participants with symptomatic and radiographic hip OA and 15 asymptomatic healthy controls underwent 3‐D motion analysis during stair ascent and descent. Trunk, pelvis, and hip kinematics as well as hip kinetics were evaluated. Analyses were performed unadjusted and adjusted for speed and leg length. In both the unadjusted and adjusted analyses, participants with hip OA ascended stairs with less hip range of motion in all three planes and a lower peak external rotation moment compared to controls. In the unadjusted analysis, hip OA participants descended stairs with greater ipsilateral trunk lean, less sagittal plane range of motion, lower peak extension moment, lower peak external rotation moment, and greater hip adduction moment impulse compared to controls. In the adjusted results, peak internal rotation moment and hip adduction moment impulse were greater in hip OA participants compared to controls. Findings show that individuals with hip OA display limited range of hip joint movement, particularly during stair ascent, and overall indicate the use of strategies (e.g., trunk lean; lower peak external rotation moment; higher adduction moment impulse) that implicate altered hip abductor function. Future research is required to further understand the implications of these findings on hip OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1505–1514, 2017.

     

Relationships between varus–valgus laxity of the severely osteoarthritic knee and gait,instability, clinical performance,and function

Increased varus–valgus laxity has been reported in individuals with knee osteoarthritis (OA) compared to controls. However, the majority of previous investigations may not report truly passive joint laxity, as their tests have been performed on conscious participants who could be guarding against motion with muscle contraction during laxity evaluation. The purpose of this study was to investigate how a measure of passive knee laxity, recorded when the participant is under anesthesia, is related to varus–valgus excursion during gait, clinical measures of performance, perceived instability, and self‐reported function in participants with severe knee OA. We assessed passive varus–valgus knee laxity in 29 participants (30 knees) with severe OA, as they underwent total knee arthroplasty (TKA). Participants also completed gait analysis, clinical assessment of performance (6‐min walk (6 MW), stair climbing test (SCT), isometric knee strength), and self‐reported measures of function (perceived instability, Knee injury, and Osteoarthritis Outcome Score (KOOS) a median of 18 days before the TKA procedure. We observed that greater passive varus–valgus laxity was associated with greater varus–valgus excursion during gait (R ² = 0.34, p = 0.002). Significant associations were also observed between greater laxity and greater isometric knee extension strength (p = 0.014), farther 6 MW distance (p = 0.033) and shorter SCT time (p = 0.046). No relationship was observed between passive varus–valgus laxity and isometric knee flexion strength, perceived instability, or any KOOS subscale. The conflicting associations between laxity, frontal excursion during gait, and functional performance suggest a complex relationship between laxity and knee cartilage health, clinical performance, and self‐reported function that merits further study. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1644–1652, 2017.

     

Gait after unilateral total knee arthroplasty: Frontal plane analysis

After unilateral total knee arthroplasty (TKA), osteoarthritis (OA) in the non‐operated knee often progresses. The altered gait mechanics exhibited by patients after TKA increase the loading on the non‐operated knee and predispose it to disease progression. Therefore, our objective was to examine the potentially detrimental changes in frontal plane kinetics and kinematics during walking in patients who underwent unilateral TKA. Thirty‐one subjects 6 months after TKA, 24 subjects 1 year after unilateral TKA, and 20 control subjects were recruited. All subjects underwent 3D gait analysis. In the TKA groups, the non‐operated knee had a higher adduction angle and higher dynamic loading, knee adduction moment and impulse, compared to the operated knee. This increased loading may be an underlying reason for OA progression in the non‐operated knee. Measures of loading in the control knee did not differ from that of the non‐operated knee in the TKA group, but the TKA group walked with shorter step length. While the non‐operated knee loading was not different from controls, there may be greater risk of cumulative loading in the non‐operated knee of the TKA group given the shorter step length. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:647–652, 2011     

Change in intersegmental foot and ankle motion after a high tibial osteotomy in genu varum patients

High tibial osteotomy (HTO) is a well‐established treatment for medial compartment knee osteoarthritis (OA), which shifts the weight‐bearing axis from the medial to the lateral side of the knee. As the adjacent ankle joint may be directly affected by the change in biomechanics, this study aimed to evaluate the change in the intersegmental foot and ankle motion after HTO in patients with genu varum. The study included 24 patients who underwent HTO, and 48 older healthy participants as a control group. Segmental foot kinematics were evaluated using a 3D multisegment foot model, and gait data of temporal and spatial parameters were obtained. After HTO, normalized stride length significantly increased with a tendency for increases in gait speed. In hallux kinematics relative to the forefoot, the sagittal motions of both the patients and the control group were similar throughout the majority of the gait cycle. In forefoot kinematics relative to the hindfoot, the pre‐HTO state revealed significant pronation throughout the gait cycle, while the post‐HTO state showed a similar position and motion to the control group. In hindfoot kinematics relative to the tibia, coronal motions of the pre‐HTO state showed supination throughout the gait cycle, while supination during the stance phase decreased after HTO. Genu varum patients with medial compartment knee OA showed different gait parameters and intersegmental motion during gait when compared with age‐ and gender‐matched controls. The effect of HTO was demonstrated by the normalization of midfoot compensation in patients with genu varum.     

Knee kinematics in medial osteoarthritis during in vivo weight‐bearing activities

Dynamic knee kinematics were analyzed for medial osteoarthritic (OA) knees in three activities, including two types of maximum knee flexion. Continuous x‐ray images of kneeling, squatting, and stair climbing motions were taken using a large flat panel detector. CT‐derived bone models were used for the model registration‐based 3D kinematic measurements. Three‐dimensional joint kinematics and contact locations were determined using two methods: bone‐fixed coordinate systems and by interrogation of CT‐based bone model surfaces. The femur exhibited gradual external rotation with knee flexion for kneeling and squatting activities, and gradual internal rotation with knee extension for stair climbing. From 100° to 120° flexion, contact locations showed a medial pivot pattern similar to normal knees. However, knees with medial OA displayed a femoral internal rotation bias and less posterior translation when compared with normal knees. A classic screw‐home movement was not observed in OA knees near extension. Decreased variability with both activities and methods of calculation were demonstrated for all three activities. In conclusion, the weight‐bearing kinematics of patients with medial OA differs from normal knees. Pathological changes of the articulating surfaces and the ligaments correspond to observed abnormalities in knee kinematics. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1555–1561, 2009     

Tibio-femoral loading during human gait and stair climbing.

Surgical intervention of the knee joint routinely endeavors to recreate a physiologically normal joint loading environment. The loading conditions resulting from osteotomies, fracture treatment, ligament replacements, and arthroplasties of the knee are considered to have an impact on the long term clinical outcome; however, knowledge regarding in vivo loading conditions is limited. Using a previously validated musculoskeletal lower limb model, we predicted the tibio-femoral joint contact forces that occur in the human knee during the common daily activities of walking and stair climbing. The average resultant peak force during walking was 3.1 times body weight (BW) across four total hip arthroplasty patients. Inter-individual variations proved larger than the variation of forces for each patient repeating the same task. Forces through the knee were considerably larger during stair climbing than during walking: the average resultant peak force during stair climbing was 5.4 BW although peaks of up to 6.2 BW were calculated for one particular patient. Average anteroposterior peak shear components of 0.6 BW were determined during walking and 1.3 BW during stair climbing. These results confirm both the joint contact forces reported in the literature and the importance of muscular activity in creating high forces across the joint. The magnitudes of these forces, specifically in shear, have implications for all forms of surgical intervention in the knee. The data demonstrate that high contact and shear forces are generated during weight bearing combined with knee flexion angles greater than approximately 15 degrees. Clinically, the conditions that produce these larger contact forces should be avoided during post-operative rehabilitation.     

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.     

Stair Ambulation Biomechanics Following Total Knee Arthroplasty: A Systematic Review

The purpose of this review was to summarize the biomechanical adaptations during stair ambulation that occur after total knee arthroplasty (TKA). Articles were identified by searching PubMed and Web of Science. During stair ascent, knee flexion angle at heel strike and walking velocity were reduced in TKA subjects compared to controls. Results of other variables were not consistent between studies. During stair descent only one study found any differences for knee moments in the sagittal and frontal plane between TKA subjects and controls. Other results during stair descent were not consistent between studies. Differences in methods can partially explain discrepancies between studies in this review. More studies with consistent and improved methods are needed in order to provide better understanding of stair ambulation following TKA.     

Walking, chair rising, and stair climbing after total knee arthroplasty: patellar resurfacing versus nonresurfacing

During the past decade, the technology and design of knee joint prostheses has progressed considerably. However, there is still much controversy on whether resurfacing the patella during routine total knee arthroplasty (TKA) is necessary. This study compares the biomechanics of the lower limb in patients after TKA with and without patellar resurfacing during level walking, stair climbing, and chair rising. Eighteen patients who underwent TKA by two different surgeons using the same prosthesis were studied after full rehabilitation while walking, stair climbing, and chair rising. Patients were divided between those who were resurfaced and those who were not resurfaced. An aged-matched control population was recruited for comparison. The Hospital for Special Surgery Knee Rating Scale was used to gather clinical information. Kinematic and kinetic parameters were collected using a 5-camera Motion Analysis System and an AMTI OR6-5 force platform. For level walking, patients were asked to walk at a self-selected speed down an 8-m walkway. For stair climbing, patients were asked to climb a 4-step staircase without handrail support and for chair rising, patients were asked to rise from a chair that was positioned at the height of their knee joint line. Five trials for each side were recorded for averaging and statistical analysis. Temporal-spatial parameters and kinematic and kinetic variables at the knee joint were tested for significance using the repeated measures analysis of variance (ANOVA). There were no significant differences in the biomechanics of walking, stair climbing, or chair rising between patients after TKA with and without a resurfaced patella.     

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.     

Rapid changes in gait, musculoskeletal pain, and quality of life after bariatric surgery

BackgroundJoint pain is a common musculoskeletal complaint of morbidly obese patients that can result in gait abnormalities, perceived mobility limitations, and declining quality of life (QOL). It is not yet known whether weight loss 3 months after bariatric surgery can induce favorable changes in joint pain, gait, perceived mobility, and QOL. Our objectives were to examine whether participants who had undergone bariatric surgery (n = 25; laparoscopic Roux-en-Y gastric bypass or laparoscopic adjustable gastric banding) demonstrate improvements in joint pain, gait (speed, stride/step length, width of base of support, toe angles, single/double support, swing and stance time, functional ambulatory profile), mobility, and QOL by 3 months compared with nonsurgical controls (n = 20). The setting was an orthopedics laboratory at a university hospital in the United States.MethodsThe present study was a prospective, comparative study. Numeric pain scales (indicating the presence and severity of pain), mobility-related surveys, and the Medical Outcomes Study short-form 36-item questionnaire (SF-36) were completed, and gait and walking speed were assessed at baseline and at month 3.ResultsThe bariatric group lost an average of 21.6 ± 7.7 kg. Significant differences existed between the 2 groups at month 3 in step length, heel to heel base of support, and the percentage of time spent in single and double support during the gait cycle (all P <.05). The severity of low back pain and knee pain decreased by 54% and 34%, respectively, with no changes in the control group (P = .05). The walking speed increased by 15% in the bariatric group (108–123 cm/s; P <.05) but not in the control group. Compared with the control group, fewer bariatric patients perceived limitations with walking and stair climbing by month 3. The bariatric group had a 4.8-cm increase in step length, 2.6% increase in single support time during the gait cycle, and 2.5-cm reduction in the base of support (all P <.05). The SF-36 physical component scores increased 11.8 points in the bariatric group compared with the control group, which showed no improvement by month 3 (P <.0001).ConclusionsImprovements in some, but not all, gait parameters, walking speed, and QOL and of perceived functional limitations occur by 3 months after a bariatric procedure.     

Validation of outcome measures in patients with patellofemoral syndrome

This project was supported by a grant from the Physiotherapy Foundation of Canada. The purpose of this study was to determine the reliability and validity of the following outcome measures in a group of 18 patients with patellofemoral pain syndrome: the visual analog pain scale (VAS), a functional index questionnaire (FIQ), selected temporal components of gait on level walking and ascending stairs, knee joint angle on downhill walking, and electromyographic activity of the quadriceps during stair climbing. Subjects were tested at initial assessment (time 0), after 24 hours (time 1), and after clinically significant improvement, following a course of treatment (time 2). Using the intraclass correlation coefficient (r1), the VAS (r1 = 0.603) and FIQ (r1 = 0.483) exhibited poor day-to-day reliability (time 0 versus time 1). However an ANOVA between time 0 and time 2 showed them to be valid measures for detection of clinical change (p < 0.01). No differences in the gait variables were observed from time 0 to time 1 or time 2, suggesting that gait analysis may not be sensitive enough to detect changes in pain and function in this patient population. J Orthop Sports Phys Ther 1989;10(8):302-308.     

Gait and function in patients with a femoral endoprosthesis after tumor resection

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.