Background: OSTEOARTHRITIS is a major public health consideration which leads to disability because of chronic pain, stiffness, sleeping disorder and depression. Among the herbal products Psidium Guajava L. fruit could be regarded as a potential natural remedy due to its anti-oxidant characteristics. The aim of this study was to evaluate the healing effect of Psidium Guajava L. fruit on OSTEOARTHRITIS of the knee in rats. Methods: Forty male Sprague-Dawley rats with induced OSTEOARTHRITIS by intra-articular injection of 500U of type 2 collagenase in the left knee were recruited in four treatment groups (n=10): (A) control, (B) Piascledine (10mg/kg) as positive control, (C) oral administration of hydro-alcoholic extract of Psidium Guajava L. fruit (500mg/kg), and (D) oral administration hydro-alcoholic extract of Psidium Guajava L. fruit (1000mg/kg). After 8 weeks of daily administration, the outcome was evaluated by histopathological and radiographic assessments. The data were analyzed using Kruskal-Wallis nonparametric in SPSS version 23. 00, and P<0. 05 was considered statistically significant. Results: Psidium Guajava extract exhibited good radical scavenging activities with IC50 of 0. 46 ± 0. 13 mg/mL (quercetin as a positive control). Histopathological assessments of the cartilage showed smooth and continuous articular surface with columnar cell distribution in the experimental group that received 1000mg/kg Psidium Guajava L. fruit hydro-alcoholic extract which healed better than others, especially in the control group (p-value =0. 02). The radiological assessments of the knee joints showed similar findings in histopathological assessment. Conclusion: Psidium Guajava L. fruit hydro-alcoholic extract might be regarded as an effective complementary and alternative treatment for OSTEOARTHRITIS of the knee in rats.

Arthritis of the knee is a common problem: 2% of United States population older than 17 years of age and 40% of Americans over 65 years age have clinically relevant arthritis of the knee. Degenerative arthritis is a progressive disease in active patients. Over loading the articular cartilage is harmful for cartilage nutrition.Maintaining the knee in a position without motion, like casting, for a long time deteriorates cartilage. The reduction of body mass and avoiding stair climbing and descending is a fundamental concept in prevention and treatment of knee arthritis.Analgesics without anti-inflammatory properties such as acetaminophen, are the initial medications used to treat degenerative arthritis of the knee.Nonsteroidal anti-inflammatory medications are the most commonly used drugs for treatment of degenerative arthritis of the knee joint. Cox I anti-inflammatory medications are less expensive and more effective, but has more, hepatic, GI and renal side effects.Cox 2 anti-inflammatory medications are more expensive, less effective and have less side effects. Cost-effective, risk-benefit matters should be considered in prescribing these medications.Nutritional supplement such as glucosamine and chondroitin sulfate have not shown any effect on cartilage regeneration in long term studies.Acute episodes of degenerative arthritis of the knee with pain and effusion can be treated by aspiration and intra articular steroid injections. However corticosteroid injections can increase the risk of damage to articular cartilage, should not repeat more than three to four times a year. Comparing intra-articular Hyaloronan injections with corticosteroids were found to be slower, more expensive and higher risk of local inflammatory response and overall no superiority.Quadriceps exercise, hamstring stretching and weight reduction has value in the treatment for arthritis of the knee joint.Knee braces like unloaded knee braces, elastic bandages provide a feeling of increased support and pain relief in patients. Shoe inserts like wedges decrease the forces on involved side and decrease the pain of patients.