Study on the impact of kinesiophobia after Total knee replacement on the rehabilitation of patients during hospitalization

doi:10.21203/rs.3.rs-4112352/v1

Objective:This study aims to investigate the influence of kinesiophobia on the rehabilitation outcomes of patients undergoing knee replacement surgery during their hospital stay.

Methods:The study conveniently selected patients who underwent unilateral knee replacement at a tertiary hospital in Baoding City between June 2021 and December 2021.A self-designed questionnaire was utilized to gather data on the patients' general demographic and disease information, while the Tampa Scale for Kinesiophobia (TSK) was employed to identify postoperative kinesiophobia. Out of the total sample, 33 patients scored above 37 points on the TSK, while 35 patients scored 37 points or below.The Numerical Rating Scale (NRS) was utilized to assess pain levels in two groups of patients at various time points post-surgery: upon returning to the ward after surgery (T1), the first day after surgery (T2), the second day after surgery (T3), the third day after surgery (T4), resting pain in the knee joint on the fifth postoperative day (T5), and on the day of discharge (T6). The flexion of the knee joint was measured in two groups of patients on the first postoperative day (T1^*), the third postoperative day (T2^*), the fifth postoperative day (T3^*), and the day of discharge (T4^*).The first time out of bed activities of the two groups of patients were compared, along with the results of the 2-Minute Walk Test (2-MWT) on the day of discharge and the postoperative hospital stay.

Results:The pain scores of patients in the kinesiophobia group were consistently higher than those in the non-kinesiphobia group at all time points (P<0.05). There were observed time effect, Between-group effects, and interaction effects (P<0.05). Additionally, the active knee flexion of patients in the kinesiphobia group was found to be smaller compared to the non-kinesiophobia group at each time point (P<0.05), There were observed time effect, Between-group effects, and interaction effects (P<0.05). Patients in the kinesiophobia group also exhibited delayed time to first get out of bed, shorter activity time and distance, as well as higher pain scores during activities, in comparison to those in the non-kinesiophobia group (P<0.05). Furthermore, patients with kinesiophobia walked shorter distances in the 2-minute walk test on the day of discharge and had longer hospitalization times than their non-kinesiophobia counterparts (P<0.05).

Conclusion:Kinesiophobia following knee replacement surgery has a significant impact on the rehabilitation outcomes of patients while they are hospitalized. It is important for healthcare professionals to promptly recognize and address this issue in order to enhance the rehabilitation progress of these patients during their hospital stay.

Health sciences/Signs and symptoms/Pain

Health sciences/Health care/Quality of life

Total knee arthroplasty(TKA) is considered the most effective treatment for the end-stage of knee osteoarthritis[1]. Postoperative rehabilitation exercises play a crucial role in enhancing joint function and mobility, as well as increasing patient satisfaction with the treatment. Failure to properly perform rehabilitation exercises can significantly hinder the patient's recovery of knee joint function. Failure to properly perform rehabilitation exercises can significantly hinder the patient's recovery of knee joint function.Research findings indicate that approximately 30% of individuals who undergo knee replacement surgery experience adverse effects, including significant lower limb pain and dysfunction in the knee join[2].Kinesiophobia is a unique phenomenon where patients experience an exaggerated and irrational fear of physical activity or exercise due to prolonged chronic pain, resulting in heightened pain sensitivity [3]. This condition significantly impacts the long-term prognosis of the knee joint and is considered an important independent factor[4].The impact of kinesiophobia on the efficacy of in-hospital rehabilitation exercises for patients post knee replacement surgery is not well understood. This study aims to address this gap and serve as a valuable reference for future interventional research in the field of clinical medicine.

Ethical approval

Ethical approval was obtained from the Ethics Committee of Baoding No.1 Central Hospital(2021-016).All study protocols were conformed to the principle of the Declaration of Helsinki.Written informed consents was obtained from each participant after study explanation.

Research object

Sixty-eight patients with knee osteoarthritis were conveniently recruited from a tertiary hospital in Baoding City between June 2021 and December 2021 and underwent knee replacement surgery. Inclusion criteria for this study include meeting the diagnostic criteria for knee osteoarthritis, undergoing primary unilateral knee replacement surgery, being between the ages of 50-80 years old, having no cognitive impairment, providing informed consent, and being able to cooperate with the investigation. Exclusion criteria involve suffering from serious heart, lung, kidney, or other important organ diseases, having diseases of the nervous system or musculoskeletal system that affect movement, or refusing to participate in the investigation.

Observed indicator

The questionnaire was developed by the research team based on a review of the literature and input from experts. It includes demographic and disease-related information such as gender, age, education level, marital status, main caregiver, chronic diseases, affected limbs, years of pain, pain score, preoperative knee flexion, body mass index (BMI), and duration operation time. The Tampa Scale for Kinesiophobia (TSK) consists of 17 items scored on a 4-point Likert scale ranging from 1 to 4. A score above 37 indicates kinesiophobia. The Numerical Rating Scale (NRS) for pain assesses pain levels on a scale of 0-10, with 0 indicating no pain, 1-3 mild pain, 4-6 moderate pain, and 7-10 severe pain.Active flexion of the knee joint involves the patient lying supine with the lower limbs extended as the starting point. The knee joint is then actively flexed to its maximum angle, and a long-arm protractor is used to measure the angle between the line connecting the greater trochanter of the femur to the lateral femoral condyle and the line connecting the lateral femoral condyle to the lateral malleolus. Record the time when the patient first gets out of bed, including the interval between returning to the ward after surgery and the first time they get out of bed, activity duration, activity distance, and pain level during the activity. On the day of discharge, perform the 2-Minute Walk Test (2-MWT) with a walking aid and record the distance traveled. Lastly, record the postoperative hospitalization time as the number of days from the second day after surgery to the patient's discharge date.

Research process

This study has been approved by the Ethics Committee of Baoding No.1 Central Hospital. Informed consent forms were signed by all participating patients. The patient's responsible nurse collected and filled out the general information questionnaire after the patient's admission to the hospital. Surgeries were conducted by a team of surgeons, with general anesthesia administered before the procedure. Adductor canal block was performed under ultrasound guidance. Prior to surgery, a pneumatic tourniquet was applied to the affected limb, with the pressure set between 40 kPa and 45 kPa. All surgeries utilized the medial approach to the patella, completed osteotomy, and employed Biomet Vaguard PS series prostheses.No drainage tube was left postoperatively. Following the operation, a rehabilitation exercise instruction manual will be provided to the patient by the nurse, while the attending doctor will guide them on the exercise techniques. The manual outlines daily postoperative rehabilitation exercises such as ankle pump exercises, quadriceps isometric exercises, passive and active knee flexion exercises, and specifies the frequency and duration of these exercises. The day after the patient regained consciousness and returned to the ward, the research team distributed the TSK rating scale to the patient, who completed it on site. In cases where the patient had difficulty understanding certain items, the research team members clarified them before the patient filled them out.The patient's pain level at rest was evaluated on multiple days postoperatively, including the first postoperative day (T1), second postoperative day (T2), third postoperative day (T3), fifth postoperative day (T4), and the day of discharge (T5). When the patient first got out of bed, they were accompanied by the responsible nurse, a research team member, and a family member. The research team recorded the time of activity initiation, duration, distance covered, and pain level during the activity.The patient's knee joint active flexion was measured by the attending physician on the first postoperative day (T1^*), third postoperative day (T2^*), fifth postoperative day (T3^*), and the day of discharge (T4^*) during ward rounds. Additionally, a 2-minute walk test was conducted on the morning of discharge under the supervision of the attending doctor, responsible nurse, a research team member, and a family member. The test was performed with the assistance of a walker, and the patient was instructed to complete it as quickly as tolerated. The postoperative hospitalization time was recorded by the research team members based on the patient's medical records.

Statistical analysis

SPSS 21.0 statistical software and GraphPad were utilized for data processing and statistical analysis. Group comparisons of count data were conducted using the chi-square or Fisher exact test and presented as numbers and percentages. For normally distributed measurement data, the mean ± standard deviation was reported, with group comparisons made using the independent sample t-test. The rank sum test was applied for data not adhering to normal distribution. Changes in postoperative pain level and active flexion of the knee joint were assessed using repeated measures analysis of variance. A p-value <0.05 was considered statistically significant.

A total of 68 patients were included in this study. Of these, 33 patients were classified in the kinesiophobia group (TSK>37 points) and 35 patients in the non-kinesiophobia group (TSK≤37 points). Upon comparing the general information of the two patient groups, no statistical differences were observed. Refer to Table 1 for detailed results.

Table 1：Comparison of general date of the two groups（n＝68）

	TSK≤37	TSK＞37	c²/t	P
	n=35	n=33
Gender			0.084	0.772
Male	15	13
Female	20	20
Age(year)			-1.212	0.230
	64.05±2.62	64.72±1.87
Education lever			1.975	0.578
Primary school	15	16
Junior school	10	12
Senior high school	7	4
College degree or above	3	1
Marriage			0.101	0.751
Married	31	30
Else	4	3
Nationality			0.006	0.940
The Han nationality	32	31
Else	3	2
Primary caregiver			1.853	0.396
Spouse	24	25
Offspring	11	7
Others	0	1
Other chronic diseases			0.197	0.906
None	5	6
1-2	17	15
3 or more	13	12
Surgical limb			0.003	0.983
Left knee	16	15
Right knee	19	18
Duration of knee pain			0.502	0.778
＜1year	6	5
1year--3year	21	19
＞3year	8	9
Preoperative pain score			0.848	0.399
	3.85±1.03	3.63±1.11
Preoperative knee flexion			1.092	0.279
	90.15±5.21	91.22±4.35
BMI(kg/m²)			-1.701	0.094
	23.60±1.28	24.63±3.25
Duration of the operation（h）			-0.635	0.528
	2.52±1.24	2.58±1.37

The knee joint resting pain scores of the two groups of patients at different time points after surgery were compared using repeated measures analysis of variance. Both sets of data met the criteria for normality and homogeneity of variances, with the Mauchly sphericity test yielding a result of P < 0.01. As the sphericity assumption was not met, the results of the multivariate test were considered. The analysis revealed a statistically significant time effect (F=131.297, p<0.01), indicating a decreasing trend in postoperative knee pain for both patient groups over time. Furthermore, the interaction between the time factor and grouping was also statistically significant (F=5.116, P<0.01), suggesting that the presence of kinesiophobia influenced the trajectory of pain intensity reduction over time in both groups. Figure 1 illustrates that the decline in postoperative pain scores for patients in the kinesiophobia group was less pronounced compared to those in the non-kinesiophobia group. Additionally, the inter-group effect was found to be statistically significant (F=15.016, P<0.01), highlighting a significant difference in pain scores between the two groups at each time point. Detailed results can be found in Table 2.

Table 2: Repeated measures analysis of variance results of resting pain score at different time points between the two groups after surgery

	T1	T2	T3	T4	T5	T6	Time effect	Inter-group effect	Interaction effect
Kinesiophobia group	6.8±0.9	6.4±0.9	5.9±0.7	5.4±1.0	4.3±1.1	3.2±0.8	131.297^△△	15.016^△△	5.116^△
Non-Kinesiophobia group	6.3±1.2	5.8±0.5	5.2±0.6	4.5±0.8	3.4±1.0	2.3±0.7
t-value	2.249	2.820	5.201	3.179	3.974	4.048
p-value	0.018	0.006	＜0.05	＜0.05	＜0.05	＜0.05
^△p＜0.01，^△△p＜0.001

The comparison of postoperative active knee flexion between two groups of patients at different time points was conducted using repeated measures analysis of variance. Both sets of data met the criteria for normality and homogeneity of variances, with the Mauchly sphericity test resulting in P < 0.01. As the sphericity assumption was not met, the results of the multivariate test were considered. The analysis revealed that the time factor had a statistically significant effect (F=428.297, p<0.01), indicating that active knee flexion tended to increase over time for both patient groups. Additionally, the interaction between the time factor and grouping was statistically significant (F = 16.549, p < 0.01), suggesting that the presence of kinesiophobia influenced the rate of knee flexion improvement over time in both groups. Figure 2 illustrates that patients in the kinesiophobia group exhibited a weaker increase in active knee flexion compared to those in the non-kinesiophobia group postoperatively. The between-group difference was statistically significant (F=66.025, p<0.01), indicating a significant variation in active knee flexion between the two patient groups at each time point. Specific results can be found in Table 3.

Table 3 Repeated measures analysis of variance results of active knee flexion at different time points between the two groups after surgery

	T1^*	T2^*	T3^*	T4^*	Time effect	Inter-group effect	Interaction effect
Kinesiophobia group	27.12±6.81	41.75±5.88	69.15±5.47	93.66±6.19	628.258^△△	16.546^△△	66.025^△△
Non-Kinesiophobia group	32.15±4.15	50.20±6.49	81.27±4.17	105.35±5.61
t-value	-5.966	-8.272	-9.947	-6.001
p-value	＜0.05	＜0.05	＜0.05	＜0.05
^△p＜0.01，^△△p＜0.001

When comparing the initial activities of patients in the kinesiophobia group with those in the non-kinesiophobia group, it was observed that patients in the kinesiophobia group took longer to get out of bed after surgery. Additionally, they had shorter durations for their first time getting out of bed and reported higher pain scores during this activity. These differences were found to be statistically significant. Furthermore, patients in the kinesiophobia group had longer postoperative hospitalization days compared to those in the non-kinesiophobia group, with a statistically significant variance. On the day of discharge, patients in the kinesiophobia group walked shorter distances in the 2-Minute Walk Test (2-MWT) in comparison to the non-kinesiophobia group, with statistical significance. Detailed results can be found in Table 4.

Table 4 Comparison of the first out-of-bed activity, postoperative hospitalization days, and 2-MWT results on the day of discharge between the two groups

	First time to get out of bed（h）	Duration of first activity（min）	Distance of first activity （m）	Pain score of first activity	Postoperative hospital stay（d）	2-MWT on day discharge（m）
Kinesiophobia group	35.39±9.81	4.12±1.36	21.50±4.33	6.4±1.11	8.11±1.35	38.26±7.50
Non-Kinesiophobia group	28.20±10.29	5.80±1.96	30.23±6.05	5.7±1.01	7.20±0.90	50.12±5.21
t-value	2.779	-4.006	-2.780	3.663	4.225	-5.217
p-value	0.032	＜0.05	＜0.05	＜0.01	0.01	＜0.05

Postoperative pain significantly influences early rehabilitation exercises in patients following knee replacement surgery[5]. This study revealed that patients in the kinesiophobia group experienced higher pain scores compared to those in the non-kinesiophbia at multiple time points (T1, T2, T3, T4, T5, and T6), with statistically significant differences. Pain perception is subjective and influenced not only by the underlying disease but also by the individual's psychological state, which is a crucial factor to consider[6].Factors such as prosthetic implantation, bone and soft tissue damage, joint swelling, and the use of tourniquets during knee replacement surgery can contribute to postoperative pain in patients [7]. Patients with kinesiophobia, however, tend to be more sensitive to pain and may experience heightened pain perception[8]. Additionally, these patients often exhibit poor pain coping strategies and low self-efficacy [9], potentially explaining why they report higher pain scores than those without kinesiphobia. Research finding has demonstrated a positive correlation between patients' pain scores and levels of kinesiophobia, indicating that higher TSK scores are associated with lower pain thresholds[10]. The findings of this study further support this relationship.

Early mobilization following joint replacement surgery can lead to increased muscle strength, reduced adhesion of surrounding tissues, improved joint stability, enhanced incision healing, better venous return in the lower limbs, prevention of postoperative deep vein thrombosis, and decreased hospitalization time and medical costs[]. Early ambulation is a key aspect of the enhanced recovery after surgery(ERAS) program.The study findings indicate that patients in the kinesiophobia group had a later first time out of bed (35.39h vs 28.29h), shorter activity time (4.12min vs 5.80min), and shorter activity distance (21.50m vs 30.23m) compared to those in the non-kinesiophobia group. Additionally, patients in the kinesiophobia group reported higher pain scores during activities (6.4 vs 5.7).Patients with kinesiophobia avoid active activities post-surgery due to concerns that movement may worsen pain or lead to re-injury of the knee joint. Research indicates that misconceptions about pain, uncertainty regarding the benefits of early exercise, and fear of prosthesis dislodgement are key factors influencing these individuals' avoidance of early physical activity[12].

The findings of this study indicate that patients in the kinesiophobia group exhibited significantly smaller active flexion of the knee joint at T1^*, T2^*, T3^*, and T4^* time points compared to those in the non-kinesiophobia group. This highlights the importance of knee flexion as a key prognostic indicator for functional recovery and satisfaction following knee replacement surgery in patients with osteoarthritis[13]. Specifically, patients require a minimum of 67° of knee flexion for walking on level ground, 90° for ascending stairs, 83° for descending stairs, and 115° for standing up from a sofa[14].Some scholars have noted that an increase of one point in the TSK score of patients following knee replacement surgery is associated with a decrease in knee flexion of approximately 1/2-2/3 degrees[15]. Apart from surgical factors, factors such as BMI, preoperative knee joint mobility, and postoperative active exercise also play a role in determining knee flexion after surgery[16]. Patients with kinesiophobia tend to avoid and fear exercise due to their unique psychological characteristics.In this study, medical staff conveyed postoperative exercise methods to patients and emphasized the importance of early exercise. However, due to human resource constraints, it was challenging to monitor the frequency and intensity of patients' daily exercises. As a result, evaluating and ensuring the quality of their exercise completion posed difficulties. The current shortage of medical staff and rehabilitation resources leads to a lack of supervision over patients' spontaneous exercise behavior, which often results in poor compliance. Patients may fail to adhere to the prescribed items, frequency, and intensity of the rehabilitation plan, or may stop exercising on their own accord[17].

The results of the 2-minute walk test on the day of discharge indicated that patients in the kinesiophobia group had a shorter walking distance compared to those in the non-kinesiophobia group. Previous research demonstrated that higher levels of kinesiophobia in patients were associated with shorter distances covered in the 2-minute walk test[18]. Apart from factors like lower limb muscle strength and joint function, the willingness of patients to exercise also played a significant role in the results of the walking test. Patients with kinesiophobia often have a tendency to avoid movement due to misconceptions such as fear of pain or exacerbating injuries, leading to reduced exercise motivation. This reluctance to engage in physical activity can impact the effectiveness of active rehabilitation exercises, resulting in poor recovery of quadriceps muscle strength and knee joint function, ultimately affecting the 2-minute walk test outcomes on the day of discharge.

The discharge criteria in this study focused on successful incision healing, achieving 90° of active knee flexion, and absence of serious postoperative complications. Patients in the kinesiophobia group had slightly longer hospitalization times compared to those in the non-kinesiophobia group. Patients in the non-kinesiophobia group initiated exercise earlier and experienced better exercise outcomes, which facilitated incision healing, reduced postoperative complications, and enhanced postoperative muscle strength and knee joint function. Consequently, their recovery outperformed that of patients in the kinesiophobia group, allowing them to meet discharge criteria sooner.

The study's limitations include the use of a sample from a single source and the inability to test the patient's muscle strength due to restrictions in research conditions.

Kinesiophobia following knee replacement surgery can have a substantial impact on the success of rehabilitation exercises during the hospital stay. It is crucial for clinical medical professionals to promptly recognize and address this issue in patients, ensuring collaboration among various departments such as anesthesiology, rehabilitation, and psychology. Developing specific measures and protocols is essential to enhance the rehabilitation outcomes for these individuals while they are in the hospital.

Data availability

The datasets used and analyzed during the current study are available from the figshare (https://figshare.com). Doi:10.6084/m9.figshare.25422769

Author Contribution

Yao and Zhang wrote the main manuscript text.Cui and Guo made contributions to statistics and methodology.All authors reviewed the manuscript.

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No competing interests reported.

Study on the impact of kinesiophobia after Total knee replacement on the rehabilitation of patients during hospitalization

Status:

Version 1

Abstract

Figures

Introduction

Methods and analysis

Results

Discussion

Conclusion

Declarations

Author Contribution

References

Additional Declarations

Status:

Version 1