Geometrical restoration during total hip arthroplasty is related to change in gait pattern - a study based on computed tomography and three-dimensional gait analysis.

BACKGROUND: The effect of change in hip anatomy on change in gait pattern is not well described in current literature. Therefore, our primary aim was to describe and quantify changes in hip geometry and gait pattern 1 year after total hip arthroplasty (THA) in individuals with hip osteoarthritis. Our secondary aim was to explore the effect of postoperative change in femoral neck anteversion (FNA) and femoral offset and acetabular offset (FO/AO) quota on postoperative change in hip rotation and hip adduction moment during gait, respectively, 1 year after THA". METHODS: Sixty-five individuals with primary hip osteoarthritis, scheduled for THA, were analyzed in this prospective intervention study. Participants were evaluated pre- and 1 year postoperatively with computed tomography-scans, three-dimensional gait analysis, and patient-reported outcome measures. Multiple linear regressions were performed to evaluate the association between change in joint anatomy and change in gait pattern after THA. RESULTS: One year postoperatively, global offset was symmetrical between sides as a result of decreased acetabular offset and increased femoral offset on the operated side. Quality of overall gait pattern improved, and participants walked faster and with less trunk lean over the affected side. FNA and hip rotations during walking changed equally in external and internal directions after THA and change in hip rotation during walking was associated with change in FNA in the same direction. An increase in external hip adduction moments was, on the other hand, not associated with change in FO/AO quota but with a more upright walking position and increased walking speed. CONCLUSIONS: The findings of this study suggest that geometrical restoration during THA impacts postoperative gait pattern and, in addition to known factors such as FO, height of hip rotation center, and leg length discrepancy, the FNA must also be taken into consideration. TRIAL REGISTRATION: Trial registration: Clinicaltrial.gov , NCT01512550 , Registered 19 January 2012 - Retrospectively registered.

Quantifying gait deviations in individuals with rheumatoid arthritis using the Gait Deviation Index.

OBJECTIVES: In this study we evaluated the usability of the Gait Deviation Index (GDI), an index that summarizes the amount of deviation in movement from a standard norm, in adults with rheumatoid arthritis (RA). The aims of the study were to evaluate the ability of the GDI to identify gait deviations, assess inter-trial repeatability, and examine the relationship between the GDI and walking speed, physical disability, and pain. METHOD: Sixty-three adults with RA and 59 adults with typical gait patterns were included in this retrospective case-control study. Following a three-dimensional gait analysis (3DGA), representative gait cycles were selected and GDI scores calculated. To evaluate the effect of walking speed, GDI scores were calculated using both a free-speed and a speed-matched reference set. Physical disability was assessed using the Health Assessment Questionnaire (HAQ) and subjects rated their pain during walking. RESULTS: Adults with RA had significantly increased gait deviations compared to healthy individuals, as shown by lower GDI scores [87.9 (SD = 8.7) vs. 99.4 (SD = 8.3), p < 0.001]. This difference was also seen when adjusting for walking speed [91.7 (SD = 9.0) vs. 99.9 (SD = 8.6), p < 0.001]. It was estimated that a change of ≥ 5 GDI units was required to account for natural variation in gait. There was no evident relationship between GDI and low/high RA-related physical disability and pain. CONCLUSIONS: The GDI seems to useful for identifying and summarizing gait deviations in individuals with RA. Thus, we consider that the GDI provides an overall measure of gait deviation that may reflect lower extremity pathology and may help clinicians to understand the impact of RA on gait dynamics.

Change in Gait Deviation Index after anti-tumour necrosis factor-α treatment in individuals with rheumatoid arthritis: a pilot study.

OBJECTIVES: Anti-tumour necrosis factor-alpha (TNF-α) inhibitors provide fast, effective resolution of rheumatoid arthritis (RA) inflammation. In this study we aimed to quantify the impact of TNF-α treatment on gait dynamics. METHOD: The sample comprised 16 subjects [11 female, median age 56 (range 48-66) years, median disease duration 9.5 (range 4.6-20.6) years] with RA who met the American College of Rheumatology (ACR) criteria, had lower extremity involvement, did not use walking aids, and had started TNF-α treatment within 1 week of baseline gait analysis. Gait analysis focused on three-dimensional (3D) lower extremity joint kinematics, kinetics, time and distance parameters. The Gait Deviation Index (GDI) and GDI-Kinetic were calculated. Data on gait, disease activity, and physical disability were collected at baseline and at 3.5 months. RESULTS: Following treatment with TNF-α, statistically significant improvements were found in disease activity [using the 28-joint Disease Activity Score based on C-reactive protein (DAS28-CRP); median difference (m(d)) = 2.3, p < 0.01], physical disability [Health Assessment Questionnaire (HAQ) m(d) = 0.4, p < 0.01], and pain during walking [visual analogue scale (VAS) m(d) = 11.0, p < 0.05]. Reductions in gait deviations were noted (GDI m(d) = 3.7, p = 0.04; GDI-Kinetic m(d) = 4.1, p = 0.05) along with reductions in dimensionless time and distance parameters. A moderate to good negative correlation existed between baseline GDI and GDI change scores (r(s) = -0.7, p < 0.01). CONCLUSIONS: Treatment with TNF-α improved gait dynamics in adults with RA. Significant gait deviations were, however, still present after treatment. In this study, GDI and GDI-Kinetic scores appeared to be useful outcome measures to quantify changes in gait deviations after this intervention.