Different perspectives of living with osteoarthritis and outcomes after knee arthroplasty

Abstract

Osteoarthritis (OA) is the most common joint disease affecting the population increasingly with age. Living with OA and pain can cause severe distress in an individual’s life and expectations of outcome after joint replacement surgery are generally high. Joint-related pain and functional loss are consequences of OA as the disease progresses and are also indications for surgery. The majority of patients undergoing a knee arthroplasty experience pain relief and are satisfied with the surgical outcome. However, there is an important minority with persistent pain and functional disability that needs to be addressed. The overall aim of this thesis was to investigate and describe individuals’ experiences of living with knee or hip OA, and their expectations of and outcomes after knee arthroplasty using both quantitative and qualitative methods.

Methods: Study I: Semi-structured interviews were conducted with 12 participants with knee OA who were scheduled for a knee arthroplasty within the next month. The interviews were transcribed verbatim and analyzed through qualitative thematic analysis. Study II. Semi-structured interviews were conducted with the same 12 participants as in study I, approximately one year after surgery. The interviews were transcribed verbatim and analyzed through qualitative thematic analysis. Study III. A total of 108 patients with knee or hip OA scheduled for a joint replacement assessed their preoperative pain and symptoms. Patient reported outcome measures were used: The Knee Injury and Osteoarthritis Outcome Score (KOOS) or the Hip Disability and Osteoarthritis Outcome Score (HOOS), a visual analogue scale (VAS) and the Pain-o-meter (POM), a survey consisting of sensory and affective pain descriptors. Preoperative radiographs were graded and analgesic use was assessed. Differences in pain expression were calculated comparing patients < 65 vs. ≥ 65 years as well as between women and men. A three-way ANOVA was used to assess differences in pain reporting with age, sex and joint as independent factors. Study IV. Sixty-five consecutive cases, where a stemmed total knee arthroplasty (TKA) was used, were clinically and radiographically evaluated with a mean follow-up of 5 years (range=2–9 years). Prosthetic survival was calculated. Of the 65 procedures, 24 were primary TKA due to knee instability and 41 were revision arthroplasties mostly due to aseptic loosening of the previous prosthesis.

Results: Study I. The overriding theme was “It’s not just a knee – but a whole life” with three categories: “Change from their earlier lives”, “Coping with knee problems” and “Ultimate decision to undergo surgery”. Knee OA was the main focus in the participants’ lives impacting their functional abilities, life quality, and mental well-being. Surgery was seen as the only solution to their problems but expectations regarding outcomes varied. Study II. The overriding theme of this study was “Striving for a silent knee” with two underlying categories: “The bumpy road to recovery” and “The presence of the future”. Not all participants were fully restored one year after surgery but were hoping for a better future. While some participants had started to accept living with knee problems, others were still hoping to improve. Additionally, some were pain-free and no longer thought about their knee – the knee had become silent. Study III. Patients < 65 years of age used more affective words, words with higher pain intensity values, and reported more symptoms (KOOS/HOOS) compared to those ≥ 65 years. However, younger patients had less severe radiographic OA than older adults and no differences were seen in VAS scores and the KOOS/HOOS pain subscale. These differences did not persist in the ANOVA with sex and joint as independent factors. Pain ratings, as measured by VAS, differed between women and men and women rated their pain higher than men. This difference persisted in the ANOVA with joint and age as independent factors. Women also reported more frequent analgesic use than men. No differences were found in radiographic severity of OA or the use of sensory and affective POM-Words between women and men. Using ANOVA with age and sex as independent factors, there was a statistically significant difference in intensity scores for sensory POM-Words where patients with knee OA reported higher intensity scores than those with hip OA. Study IV. For clinical outcome measures, the knee-related function and health-related quality of life were similar when comparing stemmed TKA used primary or as a revision TKA. However, patients in the primary group generally reported less pain and a greater proportion of these patients were satisfied or very satisfied with the surgical outcomes. The overall five-year survival rate with reoperation as endpoint was 82% (Confidence Interval=72–99) and was similar for primary and revision TKA. There were 12 surgical failures, of which 8 were reoperations due to deep infection. No TKA were loose radiographically but radiolucent lines on either the femoral or tibial side were seen in 36 cases.

Conclusions: Living with OA influences a person’s life on many levels. OA pain and functional disabilities lead to reduced spontaneity for engaging in different activities and creates a feeling of loss as the participants are forced to change how they live their lives. How OA affects a person differs between individuals and this should be taken into account when treating patients with OA. Younger patients may be more emotionally affected by pain than older patients and women may experience more pain than men without expressing greater emotional impact. However, pain is subjective and reflective of the individual’s own experience. This is why qualitative interviews and qualitative pain measurement may capture these stories more comprehensibly. Patients receiving a knee arthroplasty experience different levels of pain relief and satisfaction with surgical outcome. Some participants experience continued improvement up to one year after surgery, suggesting it may be valuable to provide continuous support throughout the postoperative period and to extend the postoperative follow-up to achieve the best possible outcome. Even after major orthopedic surgery, as with a stemmed TKA, overall patient satisfaction is high, with patients experiencing less pain. A stemmed TKA can be regarded as a good alternative when indications exist.