Therapeutic Effects of Intra-articular Botulinum Toxin Type A in Knee Osteoarthritis

Knee osteoarthritis (KOA) is an intractable and devastating consequence of degeneration that results in tremendous impact on daily activities. Painful disabling KOA occurs in more than 10% of people who are over 55 years old. Those who are severely disabled account for up to 25% of aging people and KOA is a major cause of total knee replacement [1-3]. Current osteoarthritis therapies largely rely on rest, weight loss, bracing and assistive devices, physical modalities, therapeutic exercises, and pharmacological interventions [4] which are unsatisfactory for the majority of severe disabled patients, who are left with ambulation deficit despite vigorous treatment intervention. Although numerous patients can be treated with surgery, some of them are not good candidates due to multiple co-morbidities. For these reasons, intra-articular (IA) treatments that reduce chronic joint pain and improve function is the long-term effective and safe alternative options. In a number of recent studies, pain intensity and functional performance resulted from osteoarthritis has been improved after IA injection of botulinum toxin type A (BoNT-A).