A 12-month prospective exploratory study of muscle and fat characteristics in individuals with mild-to-moderate hip osteoarthritis.

BACKGROUND: Reductions in lower extremity muscle strength, size and quality and increased fat content have been reported in advanced hip osteoarthritis (OA). Whether these differences are also evident at earlier stages of the disease and the extent to which they might develop over time is unclear. The main purpose of this 12-month exploratory prospective study was to compare changes in muscle and fat characteristics in individuals with mild-to-moderate hip OA and healthy controls. METHODS: Fourteen individuals with mild-to-moderate symptomatic and radiographic hip OA (n = 9 unilateral; n = 5 bilateral), and 15 healthy controls similar in age and sex without symptoms or radiographic hip OA were assessed at baseline and at 12-month follow-up. Maximal voluntary isometric strength of the hip and knee muscle groups was assessed using an isokinetic dynamometer. Lower extremity lean and fat mass were assessed using dual-energy x-ray absorptiometry, and thigh muscle and fat areas and thigh muscle density were assessed using peripheral quantitative computed tomography. RESULTS: Knee extension (p = 0.01), hip extension (p < 0.01), hip flexion (p = 0.03), and hip abduction (p < 0.01) strength, lower extremity lean mass (p < 0.01), thigh muscle area (p = 0.03), and thigh muscle density (p < 0.01) were significantly lower in hip OA compared to controls. Hip extension (p < 0.05), hip flexion (p = 0.03), and hip abduction (p = 0.03) strength significantly declined over the follow-up period in the hip OA group. CONCLUSIONS: Pre-existing deficits in hip muscle strength in individuals with mild-to-moderate hip OA were accentuated over 12-months, though no changes in symptoms or joint structure were observed. A longer follow-up period is required to establish whether strength deficits drive clinical and structural decline in these patients. Interventions to prevent or slow declines in strength may be relevant in the management of mild-to-moderate hip OA.

Individuals with mild-to-moderate hip osteoarthritis exhibit altered pelvis and hip kinematics during sit-to-stand.

BACKGROUND: Performance of the sit-to-stand (STS) task is compromised in individuals with advanced hip osteoarthritis (OA). Understanding how STS performance is altered in individuals with mild-to-moderate hip OA may inform interventions to improve function and slow disease progression. RESEARCH QUESTION: Do trunk, pelvis, and hip biomechanics differ during a STS task between individuals with mild-to-moderate hip OA and a healthy, age-matched control group? METHODS: Thirteen individuals with mild-to-moderate symptomatic and radiographic hip OA and seventeen healthy, age-matched controls performed a standardized STS task. Data were acquired using a three-dimensional motion capture system. The primary outcome measures were task duration, sagittal and frontal plane trunk, pelvis, and hip joint angles, and sagittal and frontal plane trunk and hip joint moments. Comparisons of lower-limb measures were between the most affected side in the hip OA group and a randomly chosen limb for the control group, termed the index limb, prior to and following lift-off from the chair. RESULTS: Participants with mild-to-moderate hip OA took longer to perform the STS task compared to controls. Prior to lift-off, the hip OA group exhibited greater posterior pelvic tilt, greater pelvic rise on the index side and less hip joint flexion relative to controls. Following lift-off, the hip OA group exhibited greater pelvic rise on the index side compared to controls. SIGNIFICANCE: Individuals with mild-to-moderate hip OA exhibit subtle alterations in movement strategy compared to healthy controls when completing a STS task similar, to a small extent, to adaptations reported in advanced stages of the disease. Interventions to target these features and prevent further decline in physical function may be warranted in the management of mild-to-moderate hip OA while the opportunity remains.

Individuals with mild-to-moderate hip osteoarthritis have lower limb muscle strength and volume deficits.

BACKGROUND: Individuals with advanced hip osteoarthritis (OA) exhibit generalized muscle weakness of the affected limb and so clinical practice guidelines recommend strength training for the management of hip OA. However, the extent and pattern of muscle weakness, including any between-limb asymmetries, in early stages of the disease are unclear. This study compared hip and knee muscle strength and volumes between individuals with mild-to-moderate symptomatic and radiographic hip OA and a healthy control group. METHODS: Nineteen individuals with mild-to-moderate symptomatic and radiographic hip OA (n = 12 unilateral; n = 7 bilateral) and 23 age-matched, healthy controls without radiographic hip OA or hip pain participated. Isometric strength of the hip and knee flexors and extensors, and hip abductors and adductors were measured. Hip and thigh muscle volumes were measured from lower limb magnetic resonance images. A full-factorial, two-way General Linear Model was used to assess differences between groups and between limbs. RESULTS: Participants in the hip OA group demonstrated significantly lower knee flexor, knee extensor, hip flexor, hip extensor and hip abductor strength compared to controls and had significantly lower volume of the adductor, hamstring and quadriceps groups, and gluteus maximus and gluteus minimus muscles, but not tensor fasciae latae or gluteus medius muscles. There were no between-limb strength differences or volume differences within either group. CONCLUSIONS: Atrophic, bilateral hip and knee muscle weakness is a feature of individuals with mild-to-moderate hip OA. Early interventions to target muscle weakness and prevent the development of strength asymmetries that are characteristic of advanced hip OA appear warranted.

Hip joint mechanics during walking in individuals with mild-to-moderate hip osteoarthritis.

The purpose of this case-control study was to characterise hip joint kinematics and moments during gait in people with mild-to-moderate hip osteoarthritis (OA). Eligible participants were allocated to the hip OA group (n=27) or the age-matched control group (n=26) based on radiographic and symptomatically defined inclusion criteria. Participants walked barefoot along a 10-m walkway at their self-selected gait speed. Trajectories of 43 markers attached to the trunk, pelvis, upper and lower limbs were recorded using a 12-camera motion capture system. Ground reaction force data were simultaneously collected. Individuals in the hip OA group had a 10% higher body mass, 13% slower self-selected walking speed, 10% shorter step length, 2% and 9% longer relative stance and double support duration (% stride) respectively, 41% lower sagittal plane hip range of motion, and 28% and 45% lower peak sagittal and transverse plane hip joint moments respectively during gait compared to controls (p<0.05). The finding that individuals with mild-to-moderate hip OA experienced less net hip joint loading over a reduced range of hip motion for a longer proportion of the gait cycle when walking at their preferred gait speed suggest that the mechanics of the hip joint are altered in hip OA, and could have implications for disease progression through altered mechano-biological processes within the joint.

Changes in functional capacity of patients two years after coronary artery bypass grafting surgery.

OBJECTIVE: To check changes in the functional capacity of patients undergoing coronary artery bypass grafting (CABG) by testing six-minute walk test (6MWT) following two years. METHODS: A prospective cohort study where 215 patients were enrolled who underwent CABG, 13 did not meet the criteria for inclusion. 202 patients were evaluated preoperatively, 13 died during hospitalization and 6 in the follow up of two years. Four patients were considered lost follow up. This study followed 179 patients for two years classified into active and sedentary, according to physical activity in leisure time and to the 6MWT preoperatively and 2 years later. RESULTS: One hundred and twenty patients were evaluated in the day before CABGS, being 67% male with an average age of 63 (+/- 9.75) years. Before surgery and 2 years later, 52 were active and the 6MWT distances performed had been 359m (+/- 164.47) and 439m (+/- 171.34), respectively; P= 0.016. Forty five patients were classified as sedentary before and 2 years after surgery. The 6MWT distances walked before and after surgery had been 255m (+/- 172.15) and 376m (+/- 210.92), respectively; P < 0.001. Eighty two patients transited between these two groups, 71 passed from sedentary to active and had walked before and after surgery 289m (+/- 157.15) and 380m (+/- 125.44), respectively; P= 0.001. The 11 patients who were active and passed to the sedentary group walked 221m (+/- 191.91) and 384m (+/- 63.73), respectively; P= 0.007. CONCLUSION: The functional capacity of the patients submitted to CABGS had a significant improvement in a medium period of follow-up.

Alterações na capacidade funcional de pacientes após dois anos da cirurgia de revascularização do miocárdio / Changes in functional capacity of patients two years after coronary artery bypass grafting surgery

OBJETIVO: Verificar alterações na capacidade funcional dos pacientes que se submetem à cirurgia de revascularização do miocárdio (CRM) por meio do teste de caminhada de seis minutos (TC6) no seguimento de dois anos. MÉTODOS: Estudo de coorte prospectivo, no qual foram arrolados 215 pacientes submetidos a CRM, 13 não preencheram os critérios de inclusão. Foram 202 pacientes avaliados no pré-operatório, 13 morreram no período da internação e seis no seguimento de dois anos. Quatro pacientes foram considerados perdas de seguimento. Foram acompanhados 179 pacientes no período de 2 anos, classificados em ativos e sedentários, conforme a prática de atividade física no tempo livre e submetidos ao TC6 no préoperatório e 2 anos depois. RESULTADOS: Dos 202 pacientes avaliados no pré-operatório da CRM, 67 por cento eram do sexo masculino, com idade média de 63 (± 9,75) anos. Pré e após 2 anos da CRM, 52 pacientes se mantiveram ativos e as distâncias caminhadas foram 359m (± 164,47) e 439m (± 171,34), respectivamente, P= 0,016. A distância caminhada no pré e pós-operatório, dos 45 pacientes que permaneceram sedentários, foi, respectivamente, 255m (± 172,15) e 376m (± 210,92) P<0,001. Oitenta e dois pacientes transitaram entre estes dois grupos, 71 passaram de sedentários para ativos e caminharam 289m (± 157,15) no pré e 380m (± 125,44) no pós-operatório, P= 0,001; os 11 pacientes que eram ativos e passaram a sedentários caminharam no pré 221m (± 191,91) e, no pós-operatório, 384m (± 63,73) P= 0,007. CONCLUSÃO: A capacidade funcional dos pacientes submetidos à CRM melhorou de forma importante no seguimento de médio prazo.

OBJECTIVE: To check changes in the functional capacity of patients undergoing coronary artery bypass grafting (CABG) by testing six-minute walk test (6MWT) following two years. METHODS: A prospective cohort study where 215 patients were enrolled who underwent CABG, 13 did not meet the criteria for inclusion. 202 patients were evaluated preoperatively, 13 died during hospitalization and 6 in the follow up of two years. Four patients were considered lost follow up. This study followed 179 patients for two years classified into active and sedentary, according to physical activity in leisure time and to the 6MWT preoperatively and 2 years later. RESULTS: One hundred and twenty patients were evaluated in the day before CABGS, being 67 percent male with an average age of 63 (± 9.75) years. Before surgery and 2 years later, 52 were active and the 6MWT distances performed had been 359m (± 164.47) and 439m (± 171.34), respectively; P= 0.016. Forty five patients were classified as sedentary before and 2 years after surgery. The 6MWT distances walked before and after surgery had been 255m (± 172.15) and 376m (± 210.92), respectively; P < 0.001. Eighty two patients transited between these two groups, 71 passed from sedentary to active and had walked before and after surgery 289m (± 157.15) and 380m (± 125.44), respectively; P= 0.001. The 11 patients who were active and passed to the sedentary group walked 221m (± 191.91) and 384m (± 63.73), respectively; P= 0.007. CONCLUSION: The functional capacity of the patients submitted to CABGS had a significant improvement in a medium period of follow-up.