Osteoarthritis (OA) of the knee is the commonest joint disorder in the elderly,
with a prevalence of about 30% in adults aged >60 years [1
]. About half of these subjects will show symptoms such as joint pain, stiffness, effusion and limitation of joint function. With our aging population, the prevalence of OA in the “developed” world is expected to increase. It is anticipated that OA will become the fourth leading cause of disability in the coming decades [2
The etiology of knee OA is multifactorial and includes generalized constitutional factors (e.g., aging, sex, obesity, heredity, and reproductive variables), local adverse mechanical factors (e.g., joint trauma, occupational and recreational abuse, alignment, and postmeniscectomy), and geographic factors. There is a significant genetic component to the prevalence of knee OA, with heritability estimates from twin studies of 0.39–0.65 independent of known environmental or demographic confounders [3
]. Genetic variations lead to chondrocyte alterations resulting in osteoarthritis [4
Diagnostic criteria for OA of the knee include patient history, physical examination, and radiologic and laboratory findings [6
]. However, the standard radiograph alone allows in most patients definitive diagnosis of knee OA. Other radiological modalities such as computer tomography, ultrasound imaging, MRI and bone scan can provide alternative or supplementary information [7
The OA Research Society International (OARSI) has published global, evidence-based, consensus recommendations for the treatment of OA of the hip and knee [8
]. Of the 51 modalities of treatment addressed in the OARSI recommendations, 35 have been systematically reviewed including a wide range of nonsurgical methods (e.g., physiotherapy, bracing, education, weight reduction, viscosupplementation, corticoid injections, analgesia, other anti-inflammatory treatments, etc.). Initial treatment of knee OA should be conservative. Only if symptoms persist after the appropriate use of nonsurgical treatment, surgery should be considered. Surgical treatment options are arthroscopic debridement, cartilage repair surgery, osteotomy with axis-correction, and unicompartmental or total knee arthroplasty (TKA). We will focus on the latest.
Surgical indication and choice of treatment is based on symptoms (e.g., pain and knee function), OA stage, and patient-related factors such as age, level of physical activity, and patient's comorbidities. Radiological evidence of OA alone (joint space narrowing, osteophytes, etc.) does not justify surgical intervention, which is indicated only in combination with relevant symptoms. Finally, it is the patient's degree of suffering, in correlation to radiological evidence of OA, which determines the time point of surgery. It is important that indication with OA, surgery is always a relative indication. Only in case of progressive knee instability associated to OA surgical treatment (total knee arthroplasty) should not be unnecessary delayed. The choice of surgical treatment, however, underlies in general practice personal, regional, and industry-influenced preferences as indications for different surgical and nonsurgical treatment modalities interfere with each other.
The present paper will discuss accepted surgical treatment options in knee OA. We focus on the latest developments, indications, and the chosen treatment's efficiency.