Factors Predicting the Duration of Effectiveness of Viscosupplementation in Knee Arthosis

Study Overview
=================
Brief Summary
-----------------
Knee osteoarthritis is a frequent condition whose prevalence is estimated at 7.6% of the French population aged 40 to 75, or approximately 2 million individuals . Viscosupplementation (VS) is a symptomatic treatment of knee osteoarthritis recommended by a large number of learned societies. It consists of the intra-articular injection (IA) of hyaluronic acid (HA), to reduce knee pain by restoring normal joint homeostasis impaired by endogenous HA deficiency. The IA administration of HA can be performed using 2 protocols: repeated weekly injections (3, sometimes 5 injections) and single injections. To date and there is no argument to favor either protocol. Regardless of the formula used, the safety of HA is excellent (RR of adverse reaction versus saline = 1.01, 95% CI 0.96-1.07, P = 0.6). The indication for viscosupplementation is the symptomatic treatment of mild to moderate knee osteoarthritis after failure and / or intolerance of analgesics or nonsteroidal anti-inflammatory drugs (NSAIDs). In this indication, after HA injection the responder rate is in the order of 70% to 75% at 6 months and approximately 50% at 12 months. However, the predictors of the duration of effectiveness of SV are still unknown. The objective of the study is to research the factors influencing the duration of the effectiveness of SV, under real life conditions.

Official Title
-----------------
Factors Predicting the Duration of Effectiveness of Viscosupplementation in Knee Arthosis

Conditions
-----------------
Knee Osteoarthritis

Intervention / Treatment
-----------------
* Other: none intervention


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: All adult outpatients, of both sexes, regardless of age, with a doctor-accepted diagnosis of knee OA and who have been treated with SV within the past 3 years Exclusion Criteria: Patients who have not been treated with SV in the past 3 years. Patients who have been treated with VS for an indication other than osteoarthritis of the knee. Patients in whom the assessment could not be performed reliably

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: none intervention|none intervention|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Investigate the factors influencing the duration of the effectiveness of SV, under real-life conditions | Duration (in weeks) during which the patient was satisfied with the treatment | At inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Research for predictive factors will be carried out on the duration of satisfaction | Research for predictive factors will be carried out on the duration of satisfaction | At inclusion | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
viscosupplementation