For patients suffering of osteoarthritis, only analgesic treatments such as anti-inflammatory drugs and cortisone infiltrations provide significant but temporary relief of their pain. The objective is to compare the analgesic effect of 2 infiltrations: Cingal (sodium hyaluronate and triamcinolone) versus cortisone (triamcinolone). It is anticipated that the Cingal infiltration will have a greater analgesic effect than a simple cortisone infiltration in patients with moderate to severe osteoarthritis of the shoulder.

Method:

• Randomized controlled trial
• Monocentric
• Randomization will be done using sealed envelopes

Osteoarthritis is a degenerative joint disease. The progressive erosion of cartilage generates inflammation, pain, and progressive deterioration of joint mobility. Synthetic molecules similar to hyaluronic acid have made it possible to offer patients the option of visco-supplementation by intra-articular injection. It decreases inflammation and pain. CINGAL (Anika Therapeutics, Inc., Bedford, MA), which combines the lubricating action of hyaluronic acid and the anti-inflammatory action of triamcinolone hexacetonide, is one of the available treatments. Several studies have demonstrated the effectiveness of hyaluronic acid in the relief of gonarthrosis. However, the efficacy between an infiltration of hyaluronic acid combined with triamcinolone and a corticosteroid infiltration for glenohumeral osteoarthritis is hardly reviewed in scientific studies.

Primary objective: To compare the analgesic effect of two different infiltrations.

Secondary outcome: To evaluate the patient's functional ability

It is anticipated that a CINGAL infiltration will have a greater beneficial effect than a simple cortisone infiltration in patients with mild to severe shoulder OA.

84 patients with moderate to severe shoulder osteoarthritis will be recruited to receive intra-articular infiltration of CINGAL or cortisone. The infiltration will be randomly assigned. A standard x-ray and magnetic resonance imaging examination will be performed before the infiltration. Demographic data, medical history and 2 questionnaires will be completed prior to infiltration.

Once the evaluation is completed, the patient is randomized and referred to radiology to receive his infiltration under fluoroscopy by a radiologist assigned to the project. Two electronic questionnaires and a medication diary will be sent to the patient at 1, 3 and 6 months post-infiltration.

Inclusion Criteria:

• A clinical examination that confirms the radiological diagnosis of moderate to severe primary shoulder osteoarthritis, stage II and above, according to the Samilson-Prieto classification.
• Patients aged between 20 and 90 years.
• A patient with bilateral shoulder osteoarthritis will choose the side of the infiltration, only one side can be chosen to participate in the study.
• The patient must have a clinical pain threshold of a minimum of 4/10 on the visual analogue scale.
• The patient must have the cognitive ability to read and fill out the questionnaires.
• The patient must be able to read and understand French or English

Exclusion Criteria:

• Presence of a transfixing rotator cuff tear assessed on MRI.
• No previous shoulder reconstruction surgery.
• Pregnant woman.
• A patient who has received a cortisone infiltration within 6 months prior to the start of the study.
• A patient who has received a platelet-rich plasma or a hyaluronic acid infiltration within 12 months prior to the start of the study.
• Diagnosis of avascular necrosis.
• Disease affecting the studied joint (systemic inflammatory disease, history of septic arthritis, osteonecrosis, etc.)
• Suspicion or presence of active local infectious process.
• Presence or suspicion of neoplasia or local metastasis.
• Severe trauma to the shoulder ( ≤ 3 months)
• Significant cognitive impairment or insufficient language proficiency to adequately answer the questionnaires.
• Any other serious medical condition that does not allow participation in the study or may be a contraindication to cortisone injection.