# Analysis of Spatiotemporal Gait Variables before and after Unilateral Total Knee Arthroplasty
## 4 Discussion  
This study compared the spatiotemporal gait parameters of the TKA, pre- and post-surgery, and examined the influence of the surgical side and participant's lateral dominance on these variables. After TKA, the surgical limb showed improvements in all variables related to gait, except stance time and swing time. Furthermore, the study revealed that better gait performance was obtained when surgery was performed on the non-dominant limb. Six months after surgery, participants reported improvements in extension ROM, daily activities, and reduced pain and stiffness, based on clinical parameter results. These findings are in accordance with the literature [6; 18; 29; 34]. According to [PERSON] et al. [35] after TKA, patients experience diminished pain levels and heightened daily functioning, resulting in decreased reaction time and improved movement control. Additionally, it is crucial to acknowledge that TKA contributes to the correction of axes deformities \begin{table}
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Table 3: Median and (IQR) of the difference between the spatiotemporal variables of gait pre- and post-surgery of the operated dominant and non-dominant limbs. Results in square brackets represent the relative percentual variation from pre-surgery. and joint alignment, with the rehabilitation program playing a pivotal role in modifying sensorimotor function. As expected, after surgery, participants demonstrated greater confidence when walking, evidenced by improvements in spatiotemporal variables, except for stance and swing times. However, it is important to consider the time after the surgery as a factor that can influence these results. In this study, the aim was to evaluate patients at a time frame set to allow the real examination of the surgery's clinical and functional impact. [PERSON] et al. [6] found that walking speed improvement was evident 6 months after surgery. Also, [PERSON] et al. [15] reported improvement in walking speed not sooner than 6 months after TKA. This persisted for up to 13 months after surgery, after which time a decline started to show [15]. Other studies showed that, despite improvements in patients' perception about their walking abilities, pain, and ROM, objective gait measures did not improve between both three and 18 months after surgery [12; 14]. Based on the presented literature, it can be suggested that walking speed may take several months to improve after TKA and this benefit may be lost over time. However, this is a significant positive finding because even minimal improvement of 0.1 m/s in walking speed has been associated with better functional outcomes [17]. Another improvement presented in this study is related to stride length and stride cadence which have been shown to both be reduced in KOA patients [18]. According to the KOA severity scale of [PERSON] et al. [20], a shorter stride length with a lower cadence is indicative of a higher functional severity grade. Our findings are supported by others, like [PERSON] et al. [6], that found a significant increase in stride length after TKA. Since both characteristics were improved by TKA in both limbs in our study, we can sustain that a primary TKA can have a positive functional outcome. When considering the dominance of the lower limb (right for all the participants) and the surgical side, our findings showed an improvement in the gait parameters, especially when the non-dominant limb was operated. The literature has considered laterality as an additional explanation for the functional behavior of the lower limbs during the gait, with the gait asymmetry reflecting a natural functional difference between limbs [22]. Given that both characteristics were improved by TKA in our study, we can postulate that TKA may produce positive functional outcomes in both limbs, potentially contributing to a reduction in the severity of KOA.