Biomechanics For Total Knee Arthoplasty: Changes In Knee Biomechanics And Functional Ability

Discuss about the Biomechanics for Total Knee Arthoplasty.

The article by Arnold et al., (2015) reports that knee arthroplasty is beneficial for patients at the final stage of knee osteoarthritis to improve their quality of life. The surgery is useful in eliminating abnormal joint mechanics. The researcher reported that several researches has been done on the changes in knee biomechanics after total knee arthoplasty (TKA), however there is few research on relationship between knee biomechanics and functional ability. Hence, Arnold et al., (2015) investigates on the changes in knee biomechanics after total knee arthroplasty and explores its relation of knee biomechanics during walking and physical activity. To carry out they research, they selected 15 participants who were going to have a total knee arthroplasty surgery and did a 3D gait test on them before and after of surgery to determine the movement in each person and any movement related disorders (Shull et al., 2014). Other functional activity like physical activity and use of time was assessed by 24 hour activity recall.

The researcher tried to investigate this finding because it has been found that total knee arthroplasty is associated with increased knee function and physical function, however there is little evidence exists regarding the relationship between functional ability of knees due to certain changes in the body (Howell et al., 2013). For this purpose, the research was conducted. This lack of research on the relation between elements of functional ability was their motivation for conducting the research. On analysis of similar research on the topic, the researcher found that research on physical activity after TKA were limited to simple questionnaires and this approach is inefficient in determining the frequency of improvement in functional ability. The researchers felt that the use of high resolution activity recall may help to understand the changes in knee function due to TKA. This was their motivation for carrying out research.

Their approach for investigation was to perform same midline incision TKA for all participants and same in patient physiotherapy exercises. A three dimensional gait analysis (like walking speed, peak knee flexion moment, saginal plane knee range of motions) was assessed and time spent in physical activity data were collected using 24 hour activity recall tool. The knee symptoms were judged using scales for pain, stiffness and activities of daily living. The results finding showed that after surgery significant improvement in knee biomechanics and physical activity was observed in participants. This improvement depended on total time spent daily in physical activity and energy expenditure. Hence, improvement in knee function is linked to time spent in physical activity after TKA (Arnold et al., 2015).

Abstract

The abstract of the research has clarity as it clearly introduces the background, purpose and methods employed for carrying out the research. An abstract should be brief summary of the research which a reviewer can clearly understand without reading the whole article. The credibility of the research is understood from the abstract as it clearly explains each phase of the research. It started with giving short background information on the benefits of total knee arthroplasty and the researcher immediately stated the purpose of investigation by stating that there is no valid evidence regarding the relationship between different elements functional ability after TKA (Arnold et al., 2015). The content of the study has summarize in a cohesive manner in the abstract starting from gap in similar to the topic of investigation and then moving to describing the approach used for carrying out investigation (Elo et al., 2014). However, the methods employed could have been presented in a more descriptive manner such as giving examples for certain physical activity profiles and gait analysis. This description is missing in methods part; however the researcher comes back to each type of analysis while stating the results finding in abstract. This is the only limitation of the reporting of research in abstract and it would been easily understood if the specific method were clearly stated before the research findings (Vaismoradi et al., 2013). Overall quality of the writing is good and the researcher has also taken care to inform about future scope of research in this area which is commendable.

The introduction by Arnold et al., (2015)  states the purpose of research by clearly stating what is known so far about the topic and what aspects is still ambiguous. The context of the research is clearly expressed by the researcher and it is successful in shifting audience attention to the validity of the research and what new insights the researcher can give after investigation. The introduction starts with stating the benefits of total knee arthroplasty and it describes the importance of assessment of knee function as it helps in evaluation of the success of TKA. It gives idea about hip strength and improvement in physical activity after surgery (Alnahdi et al., 2014). Any introductions of a research work should clearly state the status of research work of the area of study and the background information on the topic. For the article by Arnold et al., (2015), it is necessary to have information about current status of research analysis in knee biomechanics. An introduction can start with brief analysis of research related to knee biomechanics after total knee arthoplasty. For example Athwal et al., (2014) gives information about reason of biomechanic instability after total knee arthroplasty while Levinger et al., (2013) investigated the biomechanical changes in lower limb after TKA. All this elements were efficiently covered by the researcher in the introduction section after analysis of relevant literature. The significance of the study was mentioned by stating that biomechanical data will be a new approach to assess mobility after TKA.

Methods

The main aspect of method sections of a research article is the variable chosen for the study as this variable will only give the answer to research questions. In reviewing methodology of research by Arnold et al., (2015) it is seen that each method is relevant to assessing the biomechanics of knee movement. For example gait analysis has been done by recording three dimensional kinematics and ground reaction forces during walking. The markers fixed in thigh and hips and the variables for the gait analysis included speed of walking, peak knee flexion during initial contact and during peak flexion, knee movement during gait cycle and swing phase. The method used is commendable as it will leave no gap and provide detail analysis of relation between physical movement and knee biomechanics. Yoshida et al., (2013) has shown that quadriceps weakness is the most common post-operative impairment seen patient after TKA. Therefore the variable used for assessing quadriceps weakness in gait analysis is absolutely relevant for the area of investigation. The statistical tool was also employed for collecting use of time data for physical activity and it helped in evaluating changes in knee biomechanics by Pearson’s correlation coefficients (Arnold et al., 2015). However, the researcher would have gained more appreciation if stress were put on other physical functions such as stair climbing to get more insight into improvement of activities of daily living.

The results and discussion section must be interlinked with each other to understand the discussion presented for the research. The result of the current research on relation between knee biomechanics and physical activity after TKA is very important. Gait analysis was done before and six months after the surgery to determine the improvement in variables like stiffness, pain and activity limitations. The results finding was accurately presented in a tabular format with use of statistical values for all type of movements like swing time, knee flexion, knee range of motion, walking speed, knee flexion moment and cardence or steps/min. It was reflective of the fact that gait patterns after six months of TKA mostly improved in patients and the walking speed also increased in patients. Another significant finding was that duration of sitting time also reduced by 66 minutes per day post surgical intervention (Arnold et al., 2015). The correlation between knee symptoms and physical activity was accurately presented which was the main purpose of the study and the explanations for each were also discussed clearly by the researcher. Another study is also relevant in this regard as it explains the reason for movement asymmetries such as reduced knee excursion in the operated limb (McClelland et al., 2012)

Results

The interpretation of the findings explicitly explains the rational for each result and the reasons for a trend seen in study. Arnold et al., (2015) was successful in presenting the relation between sagittal plane knee range of movement and peak knee flexion. Positive results in this variable were associated with better ability to do chores while squatting. The researcher also explained that pain and physical activity is negatively correlated which as physical activity improved with improve in symptoms. The credibility of the research was also monitored by comparison with other research findings. However, it is recommended that increase in flexion gap should be controlled as it will lead to positive flexion on patient satisfaction after surgical intervention (Ismailidis et al., 2016). The study also gave a similar limitation of the research by stating that objectively measured knee motion can be better variables for assessing improvement in patients undergoing TKA.

The research is a significant work by the author as it provided the relations between biomechanics and physical activity. The presentation and language used for the study is succinct which clearly explains the rational for each step. The selection criteria of the sample is significant as it helps to remove biasness in the study by excluding patients with history of joint replacement or injection to the knee, patients with other conditions affecting gait and those who already had problems in walking. Another major highlight of the research is the use of research as it gives good visual presentation of the area of limbs which will be assessed during gait analysis and activity profiling. It helped reviewer to easily understand the approach taken for the research. Example of this figures are lower limb market set and model and the use of time profile (Arnold et al., 2015).  

Reference

Alnahdi, A. H., Zeni, J. A., & Snyder-Mackler, L. (2014). Hip abductor strength reliability and association with physical function after unilateral total knee arthroplasty: a cross-sectional study. Physical therapy, 94(8), 1154-1162.

Arnold, J. B., Mackintosh, S., Olds, T. S., Jones, S., & Thewlis, D. (2015). Improvements in knee biomechanics during walking are associated with increased physical activity after total knee arthroplasty: BIOMECHANICS AND ACTIVITY AFTER TKA. Journal of Orthopaedic Research, 33(12), 1818-1825. doi:10.1002/jor.22969

Athwal, K. K., Hunt, N. C., Davies, A. J., Deehan, D. J., & Amis, A. A. (2014). Clinical biomechanics of instability related to total knee arthroplasty.Clinical Biomechanics, 29(2), 119-128.

Elo, S., Kääriäinen, M., Kanste, O., Pölkki, T., Utriainen, K., & Kyngäs, H. (2014). Qualitative content analysis. Sage Open, 4(1), 2158244014522633.

Howell, S. M., Howell, S. J., Kuznik, K. T., Cohen, J., & Hull, M. L. (2013). Does a kinematically aligned total knee arthroplasty restore function without failure regardless of alignment category?. Clinical Orthopaedics and Related Research®, 471(3), 1000-1007.

Ismailidis, P., Kuster, M. S., Jost, B., Giesinger, K., & Behrend, H. (2016). Clinical outcome of increased flexion gap after total knee arthroplasty. Can controlled gap imbalance improve knee flexion?. Knee Surgery, Sports Traumatology, Arthroscopy, 1-7.

Levinger, P., Menz, H. B., Morrow, A. D., Feller, J. A., Bartlett, J. R., & Bergman, N. R. (2013). Lower limb biomechanics in individuals with knee osteoarthritis before and after total knee arthroplasty surgery. The Journal of arthroplasty, 28(6), 994-999

McClelland, J., Zeni Jr, J., Haley, R. M., & Snyder-Mackler, L. (2012). Functional and biomechanical outcomes after using biofeedback for retraining symmetrical movement patterns after total knee arthroplasty: a case report. journal of orthopaedic & sports physical therapy, 42(2), 135-144.

Shull, P. B., Jirattigalachote, W., Hunt, M. A., Cutkosky, M. R., & Delp, S. L. (2014). Quantified self and human movement: a review on the clinical impact of wearable sensing and feedback for gait analysis and intervention. Gait & posture, 40(1), 11-19.

Vaismoradi, M., Turunen, H., & Bondas, T. (2013). Content analysis and thematic analysis: Implications for conducting a qualitative descriptive study. Nursing & health sciences, 15(3), 398-405.

Yoshida, Y., Mizner, R. L., & Snyder-Mackler, L. (2013). Association between long-term quadriceps weakness and early walking muscle co-contraction after total knee arthroplasty. The Knee, 20(6), 426-431.