The present study evaluated prospectively the QoL after TKA in a cohort of 204 patients, and examined the effect of socio-demographic characteristics.
Our study demonstrated that the quality of life in patients with end stage arthritic knees presents significant differences among genders [25
]. WOMAC scores were significantly worse in women preoperatively and at 6
weeks after surgery. By the third postoperative month the WOMAC score differences among genders fully resolved [28
]. Also according to KSS measuring scale, women had significantly lower preoperative scores, but with equivalent improvement postoperatively when compared with men, at any follow-up interval. These gender differences observed preoperatively have been attributed to a delayed access of the women to surgical management for their arthritic knee until their symptoms were more severe than in men [7
]. The lower rate of the improvement observed at the 6
weeks follow-up in women may be due to the more severe preoperative disability of women and thus, to the longer periods needed to achieve improvement similar to men.
This study also demonstrated that older age does not affect negatively the functional outcome after TKA [7
]. However, the small number of older patients precludes any definite conclusions. According to the literature, the effect of obesity on the outcome of knee replacement is unclear [33
]. In the present study obese patients reported more pain, functional limitations and depressed mood before the surgical procedure, but obesity was not a significant predictor of pain and functional limitations one year after the index operation, suggesting that obesity is not related to the short-term outcome. However, the power to detect a significant BMI effect on pain and functional limitations at 12
months postoperatively was limited (power
12% and 23%, respectively), and therefore, the results should be interpreted with caution. Similarly these findings cannot address long-term concerns regarding potential premature joint failure. It must also be noted that patients with morbid obesity (BMI
) were not offered the option of TKA from the surgeons of the present series, during the study period.
In the present study, it was hypothesized that patients living in rural areas, which reflects a lower socioeconomic and educational status and limited or no access to rehabilitation facilities, were more likely to have access barriers or underutilization of health care services especially in the early postoperative period that would consequently impact their outcome after a TKA [37
]. According to our findings, residents of rural areas do not appear to have a worse outcome following TKA. A possible explanation is that access to all public medical services is equivalent and is not limited for patients of lower socioeconomic background. In addition, routine visits to the outpatient department during the follow-up period also offered the opportunity of a close patient-surgeon contact, provided information about the rehabilitation process even in cases with own care for physical therapy, and eliminated patients insecurity and lack of knowledge and care.
Some studies demonstrated that social support might play an important role in moderating the effects of pain, physical disability, and depression in patients with osteoarthritis [40
]. In addition, patients consider social support as an important factor when they are deciding the operative treatment with TKA and its timing [42
]. In the present study, patients that were married or living with others did not have a better QoL compared to those not married and living alone [43
]. A possible explanation is that other family members, friends or neighbours take care of those patients with weak social support, as the Greek public health system does not offer formal community services as district nurses, home help and care or day centre attendance. The mechanism of social support on TKA outcomes needs further investigation.
Chronic pain and depression are closely related to each other and many studies attempted to reveal the causality [44
]. Based on the assessment tools employed in our study we found a high prevalence of depression among patients preoperatively (44.2%; 9 males and 81 females) [48
]. However after the surgical procedure, levels of depression changed significantly over the course of the study, and 12
months after surgery a small amount of patients (7.35%; 3males and 12 females) remained in depressed mood. This suggests that depressed mood might be related to the levels of chronic pain and disability and is amenable to significant improvement when pain is alleviated and function is resumed after successful TKA. More evidence is needed to draw safe conclusions regarding this association.
months postoperatively the TKA lead to a significant reduction in pain, stiffness, functional disability and depressed mood with the pain dimension showing the greatest improvement, although only 5% of patients complained for mild chronic pain without obvious concomitant clinical or radiographic sights that might explain this symptom. The greatest improvement was seen in all measurements within the first 3 postoperative months with smaller changes thereafter. However, at 6
weeks after surgery patients still experienced functional limitations and stiffness despite significant improvements in pain. The finding of limited early functional recovery is consistent with the findings from other studies suggesting that after an initial period of functional limitation patients improved by 3
months after surgery [10
]. These findings have important implications for patients and their families regarding the expected physical dependencies after surgery and should stimulate a physician – patient discussion about the particular needs for assistance in the daily routine mainly for single individuals for the first 2
months after discharge from the hospital.
Based on our data, we can conclude that the baseline WOMAC pain and function scores are a strong determinant of the respective post-operative scores at 12
months. The same conclusions apply to the CES-D10 score.
We acknowledge however that this study was presents certain limitations such as the involvement of only two centres; therefore a multicenter research is needed for generalization of the results. In addition, the low proportion of males and the narrow age range of our patients, limited the usefulness of the results with respect to gender and age. The social support variable was created based upon the patients-reported preoperative living and marital status, which is only a crude measure of social support. In addition, the patients’ postoperative living conditions and marital status was not specifically investigated. Further studies need to explore these variables. The strengths of the study are its prospective design, the high rate of return to follow-up (90.2% at one year) and the use of a trained independent research assistant who recruited patients and followed them at each assessment.