Establishment of a qualified integrated care system after total knee arthroplasty as a role of regional rheumatoid and degenerative arthritis centers.

BACKGROUND: The geriatric population and advanced knee osteoarthritis are rapidly increasing in Korea, and the socioeconomic burden of total knee arthroplasty (TKA) is increasing. This study aimed to analyze the demographic, clinical and socioeconomic characteristics of patients who underwent TKA and to differentiate the factors affecting participation in inpatient-intensive rehabilitation programs after TKA in the Jeju regional rheumatoid and degenerative arthritis center established by the government. METHODS: This retrospective cohort study included 845 patients (735 females; 72.0 ± 5.8 years) diagnosed with primary osteoarthritis (OA) of the knee who underwent elective unilateral primary TKA between January 2013 and June 2016. Demographic, clinical, and socioeconomic characteristics, including age, body mass index, obesity, length of stay, OA severity, underlying disease, education level, occupation, and location of residence were reviewed. Patients were allocated to the TKA-only group (home discharge) and to the TKA + rehab group (participation in post-TKA rehabilitation). The variables were analyzed and compared before and after the establishment of the center and according to participation in intensive rehabilitation. RESULTS: Patients who underwent TKA were mostly female, in the 60 s, and had a high prevalence of comorbidities and obesity. After the rehabilitation center's establishment, the intensive post-TKA participation increased profoundly from 3% to 59.2%. Participants after the center establishment had lower mean BMI and a higher proportion of K-L grade 4 compared to those before the center establishment. The location of residence was the only factor differentiating the participation in the intensive rehabilitation. CONCLUSION: The regional rheumatoid and degenerative arthritis center was appropriate to satisfy the high unmet need for participating in the intensive rehabilitation after TKA and to execute the qualified integrated post-TKA care system. Policy support should ensure the early rehabilitation and a qualified integrated care system and prepare for the increased burden of revision. Future longitudinal studies should be conducted to assess the long-term effect of the integrated post-TKA rehabilitation program on functional outcomes and patient survivorship free from revision.

Comorbidities in Patients With End-Stage Knee OA: Prevalence and Effect on Physical Function.

OBJECTIVE: To investigate the prevalence of comorbidities and their effect on physical function, quality of life (QOL), and pain, in patients with end-stage knee osteoarthritis (OA). DESIGN: A cross-sectional study. SETTING: A rehabilitation facility at university hospital. PARTICIPANTS: Patients (N=577; 503 women and 74 men) diagnosed with end-stage knee OA between October 2013 and June 2018. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Comorbidities were as follows: osteoporosis, presarcopenia, degenerative spine disease, diabetes, and hypertension. All patients completed the following performance-based physical function tests: stair-climbing test (SCT), 6-minute walk test (6MWT), timed Up and Go (TUG) test, and gait analysis. Self-reported physical function and pain were measured using Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and a visual analog scale (VAS), respectively, and self-reported QOL was measured using EuroQoL 5 dimensions (EQ-5D) questionnaire. RESULTS: Univariate analyses revealed that patients with osteoporosis had significantly higher scores in SCT ascent, SCT descent, TUG, WOMAC pain tests, and lower scores in 6MWT, gait speed, and cadence tests than those without osteoporosis. Patients with presarcopenia recorded higher scores in SCT ascent, TUG, EQ-5D, and lower scores in 6MWT and gait speed tests than those without presarcopenia. Patients with degenerative spine disease showed higher scores in WOMAC pain and lower scores in gait speeds than those without degenerative spine disease. Patients with diabetes showed higher scores in SCT ascent than those without diabetes, and patients with hypertension showed lower scores in 6MWT than those without hypertension. After adjusting age, sex, and body mass index, SCT descent retained significant association with osteoporosis, SCT ascent showed independent association with presarcopenia and diabetes, and WOMAC pain revealed significant association with degenerative spine disease. CONCLUSION: The results confirm associations between comorbidities, performance-based and self-reported physical functions, and QOL in patients with end-stage knee OA.

Effects of Dexmedetomidine on Serum Interleukin-6, Hemodynamic Stability, and Postoperative Pain Relief in Elderly Patients under Spinal Anesthesia.

The beneficial effects of dexmedetomidine (DEX) have not been extensively investigated in elderly patients receiving spinal anesthesia. This study evaluated the effects of intravenous DEX infusion on stress and hemodynamic response, as well as on postoperative analgesia in elderly patients undergoing total knee arthroplasty (TKA). We randomly allocated 45 adult patients to 3 patient groups (n=15 each): uni-saline group patients underwent unilateral TKA with saline administration, uni-DEX group patients underwent unilateral TKA with DEX administration, and bilateral-DEX group patients underwent bilateral TKA with DEX administration. Serum interleukin-6 (IL-6) levels were significantly lower in the bilateral-DEX group than in the uni-saline group 6 and 24h postoperatively, and were negatively correlated with total DEX dosage 24h postoperatively. Bradycardia occurred more frequently in the uni-DEX and bilateral-DEX groups than in the uni-saline group. The total dose of required supplementary analgesics was significantly higher in the uni-saline group than in the uni-DEX and bilateral-DEX groups 6h postoperatively. The results indicate that perioperative intravenous DEX administration decreases postoperative serum IL-6 levels in patients undergoing bilateral TKA, and has a postoperative analgesic effect in patients undergoing unilateral or bilateral TKA.

Preoperative physical performance predictors of self-reported physical function and quality of life in patients scheduled for total knee arthroplasty.

[Purpose] To determine the preoperative self-reported and performance-based physical function of patients with end-stage knee osteoarthritis who awaited total knee arthroplasty. The preoperative physical performance factors that predicted self-reported physical function and quality of life were also identified. [Subjects and Methods] All adults with end-stage knee osteoarthritis awaiting surgery were enrolled. Before surgery, self-reported disease-specific physical function and self-reported pain were measured using the Western Ontario McMaster Universities Osteoarthritis Index, self-reported quality of life was measured using the EuroQOL five dimensions questionnaire, and physical performance tests were performed, the 6 minute walk test, the timed up-and-go test, instrumental gait analysis, and measurement of isometric knee flexor and extensor strength of the surgical and nonsurgical knees. [Results] In total, 55 adults (49 females; 73.3 ± 6.1 years) were included. This study showed that several preoperative self-reported and physical performance factors were predictive of self-reported physical function and quality of life. [Conclusion] In patients with end-stage knee osteoarthritis, preoperative pain and dynamic balance ability were the most powerful predictors of self-reported physical function. Preoperative pain and exercise tolerance were the most powerful predictors of quality of life. Preoperative rehabilitation strategies that focus on dynamic balance, aerobic, and resistance exercises may improve surgical outcomes.

Trend in hip fracture incidence and mortality in Korea: a prospective cohort study from 2002 to 2011.

This prospective longitudinal cohort study was to assess the 10-yr hip fracture incidence and mortality trend of person ≥50 yr of age between 2002 and 2011 of eight hospitals in Jeju Island. Sex-specific incidence rate (per 100,000 person-years) were calculated based on that estimated for the population in the United States in 2008. Poisson and logistic regressions were used to examine trends in incidence and mortality. There was a 101% increase in the number of hip fractures from 151 in 2002 to 304 in 2011. The crude incidence of hip fractures in the Jeju population ≥50 yr of age increased from 126.6/100,000 to 183.7/100,000. The fracture incidence in the population standardized to the 2008 population in the United States increased from 100.6/100,000 for men and 194.4/100,000 for women in 2002 to 114.2/100,000 for men and 278.4/100,000 for women in 2011. The annual increasing incidence rate of hip fracture was 4.3% (5.3% in women and 2.2% in men). Poisson regression did not show significant trends in the mortality rates for all age groups or for both genders. The total number of hip fractures increased two-fold and the incidence rate of hip fractures increased markedly during the 10-yr study period.

The effect of mechanical massage on early outcome after total knee arthroplasty: a pilot study.

[Purpose] The aim of this study was to evaluate the efficacy of mechanical massage via Endermologie(®) after total knee arthroplasty in reducing edema and pain and improving knee range of motion, in the early postoperative period. [Subjects and Methods] Eighteen patients with knee edema following total knee arthroplasty were randomly assigned to the intervention group (n=8) or the control group (n=10). The intervention group received mechanical massage therapy using Endermologie(®) and the control group received conventional physical therapy for 20 minutes a day, 5 times a week from the seventh day postsurgery. Clinical assessments included active knee flexion and extension range of motion, knee pain using a numeric rating scale, the operated limb circumference, the soft tissue cross-sectional area using ultrasonography, the extracelluar fluid volume, and single frequency bioimpedance analysis at 5 kHz using bioelectrical impedance spectroscopy. [Results] Both groups showed significant reduction in edema and pain, and improvement in active knee flexion at the end of treatment. There were no significant inter-group differences before or after treatment. [Conclusion] Mechanical massage could be an alternative way of managing knee edema after total knee arthroplasty in early postoperative recovery.

Revision of ceramic head fracture after third generation ceramic-on-ceramic total hip arthroplasty.

We performed 24 revisions of fractures of third generation ceramic heads. The stem was not changed in 20 revisions; a new ceramic-on-ceramic bearing was used in four and a metal-on-polyethylene bearing in 16. The stem was changed in four revisions; a new ceramic-on-ceramic bearing was used in three and a metal-on-polyethylene bearing in one. During the follow-up of 57.5 months, complications occurred in five hips among the 20 stem retained revisions: a fracture of the new ceramic head in two, metallosis with pseudocyst in two, and femoral osteolysis with stem loosening in one. However, there were no complications in the four revisions where the stem was changed. Revision surgery after ceramic head fracture shows high rates of early complications. We recommend stem revision in cases of THA failure due to fracture of a modern ceramic head.

Morbidity and mortality in Jeju residents over 50-years of age with hip fracture with mean 6-year follow-up: a prospective cohort study.

This prospective cohort study was performed to estimate the morbidity and mortality with 790 patients over 50-yr of age that sustained a femoral neck or intertrochanteric fracture from 2002 to 2006, followed-up for a mean of 6 yr (range, 4 to 9 yr). Crude and annual standardized mortality ratios (SMRs) were calculated; and mortalities in the cohort and the age and sex matched general population were compared. The risk factors on mortality and activities pre- and post-injury were assessed. Accumulated mortality was 16.7% (132 patients) at 1 yr, 45.8% (337 patients) at 5 yr, and 60% (372 patients) at 8 yr. SMR at 5 yr post-injury was 1.3 times that of the general population. Multivariate analysis demonstrated that age (OR, 1.074; 95% CI, 1.050-1.097; P<0.001), woman (OR, 1.893; 95% CI, 1.207-2.968; P=0.005), and medical comorbidity (OR, 1.334; 95% CI, 1.167-1.524 P<0.001) were independently associated with mortality after hip fracture. Only 59 of the 150 patients (39.3%) who were able to ambulate normally outdoors at preinjury retained this ability at final follow-up. Patients with a hip fracture exhibits higher mortality at up to 5 yr than general population. Age and a preinjury comorbidity are associated with mortality.

Giant extra-articular synovial osteochondromatosis of the sinus tarsi: a case report.

A 32-year-old male presented with painful swelling of the sinus tarsi that occurred during daily activities. Diagnostic imaging suggested the presence of a large synovial osteochondromatosis that blocked subtalar motion with deformity of the adjacent bone. The large bony mass was excised, and normal subtalar motion was achieved.

Functional outcomes and length of stay with early and high-intensity rehabilitation after simultaneous bilateral total knee arthroplasty.

BACKGROUND: Length of stay and functional outcomes after total knee arthroplasty (TKA) are related to the timing and intensity of post-operative rehabilitation. OBJECTIVE: To determine the effectiveness of early and high-intensity rehabilitation after simultaneous bilateral TKA. METHODS: Prospective cohort data of 156 patients (11 men and 145 women; average age 72.0 ± 5.6 years) who underwent simultaneous bilateral primary TKA were analyzed. The intervention group (n= 82) underwent a high-intensity rehabilitation (phase II) after early postoperative standard rehabilitation (phase I) between June 2019 and May 2021. The control group (n= 74) underwent a lower-intensity rehabilitation (phase II) after phase I rehabilitation between July 2017 and May 2019. The timed up-and-go (TUG) test, timed stair climbing test (SCT), 6-minute walk test, isometric knee extensor and flexor strength of both knees, knee flexion and extension range of motion, Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) for pain, stiffness, and functional levels, and the EuroQol five-dimension questionnaire were assessed preoperatively and 6 weeks after TKA. RESULTS: The average length of hospital stay was shortened by 5.7 days (p< 0.001). Phase II rehabilitation started earlier in the intervention group than in the control group (7.7 ± 1.3 vs 13.5 ± 2.0, p< 0.001). Compared with the control group, the intervention group showed significant improvements in the measures of mobility (WOMAC-function and SCT) and strength (isometric strength of both knee extensors and flexors) 6 weeks after TKA by statistically controlling for age and preoperative functional status. CONCLUSION: This study demonstrated that early and high-intensity rehabilitation could achieve functional improvement and shorten the length of hospital stay.

The combination of osteoporosis and low lean mass correlates with physical function in end-stage knee osteoarthritis: A retrospective observational study.

We aimed to investigate the prevalence of osteoporosis and low lean mass, either together or in isolation, and their association with physical function, pain, and quality of life (QOL) in patients with end-stage knee osteoarthritis (OA). This retrospective cross-sectional observational study included 578 patients (77 males and 501 females) diagnosed with end-stage knee OA. Patients were divided into 4 groups based on body composition parameters: control, osteoporosis, low lean mass, and osteoporosis + low lean mass. All participants underwent performance-based physical function tests, including a stair climbing test (SCT), a 6-minute walk test, a timed up and go test, and instrumental gait analysis, to examine spatiotemporal parameters. Self-reported physical function and pain levels were measured using the Western Ontario McMaster Universities Osteoarthritis Index and visual analog scale, respectively. Self-reported QOL was measured using the EuroQOL 5 dimensions (EQ-5D) questionnaire. Of 578 patients, 268 (46.4%) were included in the control group, 148 (25.6%) in the osteoporosis group, 106 (18.3%) in the low lean mass group, and 56 (9.7%) in the osteoporosis + low lean mass group. Analysis of variance revealed that the scores for the osteoporosis + low lean mass group in the SCT-ascent, SCT-descent, and timed up and go test were significantly higher, whereas those for the 6-minute walk test, gait speed, and cadence were significantly lower than those for the other groups (P < .05). After adjusting for age, sex, and body mass index, multiple linear regression analysis identified SCT-ascent (ß = 0.140, P = .001, R2 = 0.126), SCT-descent (ß = 0.182, P < .001, R2 = 0.124), gait speed (ß = -0.116, P = .005, R2 = 0.079), and cadence (ß = -0.093, P = .026, R2 = 0.031) as being significantly associated with osteoporosis + low lean mass. Thus, osteoporosis + low lean mass correlates with poor physical function, but not pain and QOL, in patients with end-stage knee OA.

Orthopedic surgeon's awareness can improve osteoporosis treatment following hip fracture: a prospective cohort study.

Through retrospective Jeju-cohort study at 2005, we found low rates of detection of osteoporosis (20.1%) and medication for osteoporosis (15.5%) in those who experienced hip fracture. This study was to determine the orthopedic surgeons' awareness could increase the osteoporosis treatment rate after a hip fracture and the patient barriers to osteoporosis management. We prospectively followed 208 patients older than 50 yr who were enrolled for hip fractures during 2007 in Jeju-cohort. Thirty four fractures in men and 174 in women were treated at the eight hospitals. During the study period, orthopedic surgeons who worked at these hospitals attended two education sessions and were provided with posters and brochures. Patients were interviewed 6 months after discharge using an evaluation questionnaire regarding their perceptions of barriers to osteoporosis treatment. The patients were followed for a minimum of one year. Ninety-four patients (45.2%) underwent detection of osteoporosis by dual energy x-ray absorptiometry and 67 (32.2%) were prescribed medication for osteoporosis at the time of discharge. According to the questionnaire, the most common barrier to treatment for osteoporosis after a hip fracture was patients reluctance. The detection and medication rate for osteoporosis after hip fracture increased twofold after orthopedic surgeons had attended the intervention program. Nevertheless, the osteoporosis treatment rate remains inadequate.

Associations Between Obesity With Low Muscle Mass and Physical Function in Patients With End-Stage Knee Osteoarthritis.

OBJECTIVE: To investigate the prevalence of obesity with low muscle mass and its impact on physical function, quality of life (QOL) and pain in patients with end-stage knee osteoarthritis over 65 years old. METHODS: In this cross-sectional study, we assessed a total of 562 patients. After separating the group into males and females, we divided patients into 4 further groups: normal BMI with normal muscle mass, obesity with normal muscle mass, normal BMI with low muscle mass and obesity with low muscle mass. All patients completed stair climbing test (SCT), 6-minute walk test, timed up and go test (TUG), instrumental gait analysis, Western Ontario McMaster Universities Osteoarthritis Index, VAS, and EuroQOL 5 dimensions questionnaire. RESULTS: Obesity with low muscle mass was diagnosed in 6 males subjects (7.8%) and 9 female subjects (1.9%). Patients with obesity and low muscle mass performed the SCT-ascent and descent significantly slower than other body composition groups in both males and females. TUG in males and gait speed in females were also significantly slower in the obesity with low muscle mass group. Stepwise multiple linear regression analysis revealed that in males, obesity with low muscle mass was significantly predictive of SCT ascent (ß = 0.409, p < 0.001), SCT-descent (ß = 0.405, p < 0.001), and TUG (ß = 0.283, p = 0.009), and in females, obesity with low muscle mass was significantly predictive of SCT-ascent (ß = 0.231, p < 0.001), SCT-descent (ß = 0.183, p < 0.001), and gait speed (ß=-0.129, p = 0.004). CONCLUSIONS: This study confirms that the combination of obesity and low muscle mass is associated with impaired physical function in patients with end-stage knee osteoarthritis.

Performance-based physical function correlates with walking speed and distance at 3 months post unilateral total knee arthroplasty.

BACKGROUND: After total knee arthroplasty (TKA), walking speed and distance are main concerns of patients. RESEARCH QUESTION: Which physical functions affect walking speed and distance after TKA? METHODS: Cross-sectional data from 149 patients who underwent unilateral primary TKA and completed performance-based physical function tests. Instrumental gait evaluation for spatiotemporal parameters, isometric knee extensor and flexor strength of both knees, 6-minute walk test (6MWT), timed up-and-go (TUG) test, timed stair climbing test (SCT), and knee flexion and extension range of motion (ROM) of surgical knee were examined. Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and EuroQol five dimensions (EQ-5D) questionnaires were also performed. RESULTS: Univariate analyses revealed that post-operative walking speed showed significant positive correlations with cadence, stride length, propulsion index of surgical and non-surgical knee, peak torque (PT) of the extensor of surgical and non-surgical knee and flexor of surgical and non-surgical knee, 6MWT, EQ-5D, and significant negative correlations with gait cycle duration, TUG, SCT-ascent and descent, and WOMAC-pain scores. Post-operative walking distance had significant positive correlations with walking speed, cadence, stride length, swing phase duration, propulsion index of surgical and non-surgical knee, PT of the extensor of surgical and non-surgical knee, EQ-5D, and significant negative correlation with gait cycle duration, double support duration, TUG, SCT-ascent and descent. In the multivariate linear regression analyses, TUG, cadence, stride length and propulsion index of non-surgical knee were factor correlated with post-operative walking speed. The SCT-ascent and descent, TUG and propulsion index of surgical knee were factor correlated with post-operative walking distance. SIGNIFICANCE: Physical performance factors correlated with walking speed and distance at 3 months after surgery. Based on these observations, rehabilitation of bilateral muscle strength and functional mobility would be important for functional recovery after unilateral TKA.

Influence of Comorbidities on Short-Term Functional Outcomes After Unilateral Total Knee Arthroplasty.

OBJECTIVE: The aim of the study was to determine the effect of comorbidities on physical function and quality of life of patients at 3 mos after total knee arthroplasty. DESIGN: Data from 140 patients who underwent a primary unilateral total knee arthroplasty were examined retrospectively. Comorbidities were osteoporosis, presarcopenia, degenerative spine disease, diabetes, and hypertension. All patients completed the following: range of motion, stair climbing test, 6-min walk test, Timed Up and Go Test, peak torque of the knee extensor and flexor, instrumental gait analysis, Western Ontario McMaster Universities Osteoarthritis Index, and EuroQoL five-dimension questionnaire. RESULTS: Univariate analyses revealed that osteoporosis led to a significantly longer time to complete the stair climbing test-ascent, stair climbing test-descent, and Timed Up and Go Test and to lower scores for the 6-min walk test and peak torque of the knee extensor. Patients with degenerative spine disease showed significant negative scores for knee extension range of motion. Diabetes showed a negative correlation with peak torque of the knee extensor and knee flexion range of motion, as well as a higher Western Ontario McMaster Universities Osteoarthritis Index-stiffness score. Multivariable linear regression analysis showed that Western Ontario McMaster Universities Osteoarthritis Index-stiffness remained independently associated with diabetes. Six-minute walk test, Timed Up and Go Test, stair climbing test-ascent, and peak torque of the knee extensors showed a significant association with osteoporosis. CONCLUSIONS: Comorbidities, particularly osteoporosis and diabetes, affect short-term functional outcomes 3 mos after total knee arthroplasty.

Autologous chondrocyte implantation in the knee using fibrin.

Autologous chondrocyte implantation (ACI) is widely used to treat symptomatic articular cartilage injury of the knee. Fibrin ACI is a new tissue-engineering technique for the treatment of full-thickness articular cartilage defects, in which autologous chondrocytes are inserted into a three-dimensional scaffold provided by fibrin gel. The objective of this study is to document and compare mean changes in overall clinical scores at both baseline and follow-up. Fibrin ACI was used to treat deep cartilage defects of the femoral condyle in 30 patients. There were 24 men and 6 women with a median age of 35 years (range 15-55) and with a mean defect size of 5.8 cm(2) (range 2.3-12). Clinical and functional knee evaluations were performed using different scoring systems, MRI was performed 24 months postoperatively, and arthroscopy was performed 12 months postoperatively. All patients achieved clinical and functional status improvements following surgery (P < 0.01). The mean scores of the Henderson classification (MRI evaluation) significantly improved from 14.4 to 7 (P = 0.001), and no graft-associated complications were noted. Arthroscopic assessments performed 12 months postoperatively produced nearly normal (grade II) International Cartilage Repair Society scores in 8 of the 10 study patients. Fibrin ACI offers the advantages of technical simplicity, minimal invasiveness, a short surgery time, and easier access to difficult sites than classical ACI. Based on the findings of this clinical pilot study, we conclude that fibrin ACI offers a reliable means of treating articular cartilage defects of the knee.

Physical Performance Correlates with Self-Reported Physical Function and Quality of Life in Patients at 3 Months after Total Knee Arthroplasty.

BACKGROUND: Although total knee arthroplasty (TKA) is an effective treatment for knee osteoarthritis, assessment of postoperative outcomes remains unclear. This study aimed to identify postoperative physical performance factors that are correlated with self-reported physical function and quality of life (QoL) at 3 months after unilateral TKA. METHODS: In total, 158 patients who underwent unilateral primary TKA completed performance-based physical function tests at 3 months after surgery, including Stair Climbing Tests (SCT), 6-Minute Walk Tests (6MWT), Timed Up and Go tests (TUG), and instrumental gait analysis. We also measured the isometric knee flexor and extensor strengths of the operated and non-operated knees. Self-reported physical function and QoL were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Euro-QoL Five Dimensions (EQ-5D) questionnaire, respectively. RESULTS: Bivariate analyses showed that WOMAC function and EQ-5D were correlated with age, other self-reported measures, and performance-based measures. The WOMAC pain (r=0.71, p<0.001) showed a high positive correlation. While the EQ-5D (r=-0.7, p<0.001) showed a highly negative correlation with WOMAC function, WOMAC pain (r=-0.67, p<0.001) showed a moderately negative correlation with EQ-5D. In multivariate linear regression analyses, WOMAC pain, peak torque of the flexor of the non-operated knee, and reductions in extensor and stride length were associated with self-reported physical function, whereas WOMAC pain, SCT ascent, and cadence were associated with postoperative QoL. CONCLUSIONS: Physical performance factors were significantly associated with self-reported physical function and QoL in patients at 3 months after unilateral TKA. These findings suggest that performance-based physical function could be used to assess outcomes after TKA.

Effects of body weight support and gait velocity via antigravity treadmill on cardiovascular responses early after total knee arthroplasty.

To investigate the effects of body weight support (BWS) and gait velocity on cardiovascular responses during walking on an antigravity treadmill early after unilateral and bilateral total knee arthroplasty (TKA).This study was a cross-sectional study design. Fifty patients (7 males and 43 females; average age, 72.0 ±â€Š5.1 years) at 4 weeks after unilateral (n = 25) and bilateral (n = 25) primary TKA were enrolled in the study. Subjects walked on an antigravity treadmill at speeds of 2.5 km/hour and 3.5 km/hour with 3 levels (50%, 25%, and 0%) of BWS. Cardiovascular responses were monitored by measuring oxygen consumption (VO2), heart rate (HR), systolic and diastolic blood pressure (SBP/DBP), the respiratory exchange ratio (RER), and rate pressure product (RPP). Borg rating of perceived exertion (RPE) and a visual analog scale (VAS) of knee pain were recorded immediately after each trial.There were no significant differences in cardiovascular responses between the unilateral and bilateral TKA groups. In the repeated measures Analysis of Variance, VO2 levels, HR, RPP, RPE, RER, and VAS were significantly increased in proportion to 3 levels (50%, 25%, and 0%) of BWS for unilateral and bilateral TKA groups, respectively. Meanwhile, SBP and DBP were unaffected by differences in BWS. At 3.5 km/hour, VO2, RPE, and RER values were statistically greater than those at 2.5 km/hour under the same BWS conditions.We found that the reduction in the metabolic demand of activity, coupled with positive pressure on the lower extremities, reduced VO2 and HR values as BWS increased.Cardiovascular responses vary according to BWS and gait velocity during antigravity treadmill walking. BWS rather than gait velocity had the greatest effect on cardiovascular responses and knee pain.

Preoperative physical factors that predict stair-climbing ability at one month after total knee arthroplasty.

OBJECTIVE: To identify preoperative physical performance factors that predict stair-climbing ability at 1 month after total knee arthroplasty. DESIGN: Prospective cohort study. SETTING: University-based rehabilitation centre. SUBJECTS: Eighty-four patients who underwent a primary unilateral total knee arthroplasty Methods: Before and 1 month post-operation, the patients completed physical performance tests, including a stair-climbing test, a 6-minute walk test, a Timed Up-and-Go test, tests of the isometric flexor and extensor strength of the operated and non-operated knees, and instrumental gait analysis. Disease-specific physical function was measured by the Western Ontario McMaster Universities Osteoarthritis Index. RESULTS: Correlation analysis showed that postoperative stair-climbing test scores were significantly correlated with preoperative physical performance and function. Linear regression analysis showed that postoperative stair-ascent scores were correlated with preoperative Timed Up-and-Go test scores and peak torque of the extensor of the operated knee. Postoperative stair-descent scores were positively correlated with preoperative stair-descent scores and age. CONCLUSION: The results show that preoperative balance ability and quadriceps strength in the operated knee could influence postoperative stair-climbing ability at 1 month after total knee arthroplasty. These findings will be useful for developing pre- and post-operative rehabilitation strategies for improving stair-climbing ability in the early stages after total knee arthroplasty.

Bilateral Quadriceps Muscle Strength and Pain Correlate With Gait Speed and Gait Endurance Early After Unilateral Total Knee Arthroplasty: A Cross-sectional Study.

OBJECTIVE: The aim of this study was to determine the correlations between objective performance-based physical function, self-reported physical function, quality of life, and gait function at 1 mo after unilateral total knee arthroplasty. DESIGN: Cross-sectional data from 195 patients who underwent unilateral primary total knee arthroplasty were analyzed. The isometric knee extensor and flexor strength of both knees, gait parameters, 6-min walk test, timed up-and-go test, timed stair-climbing test, knee flexion and extension range of motion of surgical knee, Western Ontario McMaster Universities Osteoarthritis Index pain, stiffness, and functional levels, EuroQol five-dimensions questionnaire, and visual analog scale for knee pain were assessed. RESULTS: In bivariate analyses, both postoperative gait speed and gait endurance had significant positive correlations with postoperative peak torque of the extensor and flexor of both knees, cadence, stride length, and significant negative correlation with timed up-and-go, stair-climbing test ascent, stair-climbing test descent, visual analog scale, Western Ontario McMaster Universities Osteoarthritis Index pain, stiffness, and function levels. In the linear regression analyses, postoperative peak torque of the extensors of both knees and VAS for knee pain were factors correlated with postoperative gait speed and gait endurance. CONCLUSIONS: Quadriceps muscle strength of both knees and knee pain were important factors correlated with gait function early after total knee arthroplasty.