by Mr Nikhil Shah, Consultant Trauma and Orthopaedic Surgeon
Total knee replacements (TKR) performed for severe painful knee arthritis (figure 1) in well-selected patients are generally successful operations in improving the pain levels and mobility. However there remains a significant proportion of patients who are unhappy with the outcome of their new knee. Recent studies show that apart from claims for technical errors, there has also been a rise in claims for non-specific dissatisfaction.
This percentage of patient dissatisfaction is approximately 20-25% (range 10-50%) in published literature. That means every 5th patient with TKR could potentially be dissatisfied or even bitterly disappointed with the outcome. The satisfaction levels are even lower in younger patients, who are coming up for knee replacements with increasing incidence. This may happen even if the surgery is deemed to be otherwise successful using objective parameters and is technically well-performed.
It is important to understand the reasons for dissatisfaction to try and minimize the number of unhappy patients. Patients expect pain relief, improved walking, return to work and sports, and improved feeling of well-being. However, studies show that many patients are overly optimistic and have unrealistic expectations of the expected outcomes after TKR.
Patient satisfaction is difficult to define and even more difficult to measure. It encompasses unfulfilled expectations, incomplete pain relief, reduced movement, persistent limp, problems returning to work or to an active lifestyle, complications, and also their overall experience of the healthcare system under which they had the surgery.
It is recognised that physical as well as psychological factors (pre-existing depression, somatization dysfunction) both contribute to dissatisfaction. Health related factors such as multiple previous knee operations, medical comorbidities, and high BMI are associated with lower satisfaction. It is well-recognised that performing a total knee replacement for less severe grades of osteoarthritis in patients who are otherwise functioning quite well, is also linked to dissatisfaction.
Persistent residual pain is one of the most common reason for dissatisfaction in clinical practice and also a common reason for litigation. A painful total knee replacement needs thorough evaluation to find out if there is a correctable cause such as infection, loosening of the components, instability, malalignment, or patellar maltracking. However there can be persistent pain even in a well-aligned and well-fixed joint. Complex regional pain syndrome can be an infrequent but important cause of post-operative pain which is quite difficult to treat.
Another common reason for dissatisfaction is stiffness, or failure to obtain the range of movement the patient expected. This can be due to technical problems or due to a condition called arthrofibrosis which leads to scar formation inside the knee replacement.
Dissatisfaction may lead to compromise of the doctor- patient relationship and can be a reason for litigation. It is important to carefully select patients and avoid total knee replacements with lower grades of arthritis as shown in many studies. It is important to appreciate the role of conservative management in early stages of arthritis or to consider other joint preserving options in the appropriate indications. Managing expectations and thorough counselling is vital. Patients must understand the goals and limitations of surgery. It is worth spending time to explain the importance of correcting modifiable risk factors such as smoking and high body mass index. A good preoperative patient education programme is also very helpful in preparing the patient for surgery. Preoperative counseling regarding the risks of incomplete pain relief could substantially reduce the number of unhappy patients and legal claims.
Mr Nikhil Shah
Consultant Trauma and Orthopaedic Surgeon Wrightington Hospital