Does Subacromial Injection With Glutamate Receptor Antagonist, Ketamine, Attenuate Pain in Rotator Cuff Tendinopathy?

Helse Møre og Romsdal HF

Status and phase: Completed; Phase 3; Phase 2

Conditions: Rotator Cuff Tendinitis; Chronic Pain

Treatments: Drug: NaCl 9%; Drug: Ketalar

Study type: Interventional

Funder types: Other

Identifiers

NCT02967640

2012/1199

2012-002782-35 (EudraCT Number)

Details and patient eligibility

About

The hypothesis of the present study is that in patients with rotator cuff tendinopathy a specific pharmacological blocking of peripheral glutamate-receptor N-methyl-d-aspartate receptor type1 (NMDAR) glutamate receptors will result in pain alleviation. Activated NMDAR1 has been demonstrated to be crucial for pain regulation in various pain disorders, and in biopsies from patients with tendinopathy, NMDAR1 was found to be activated.

To test this hypothesis a specific NMDA receptor antagonist, ketalar (ketamine), will be injected guided by ultrasound into the subacromial space in patients with rotator cuff tendinopathy, and subsequently the pain response will be assessed.

Enrollment: 14 patients

Sex: All

Ages: 40+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• diagnosis of rotator cuff tendinopathy by exercise-related shoulder pain with positive impingement tests as described by Hawkins and Neers, and MRI findings consistent with tendinopathy.
• Symptom duration at least 1 year to ensure neuronal ingrowth and NMDAR expression

Exclusion criteria

• previous surgery in any shoulder.
• previous cortisone use, either as injections or orally
• symptoms or signs of cervicobrachialgia or polyneuropathy
• full thickness rotator cuff ruptures verified by MRI
• primary inflammatory mediated pain, hence, patients with glenohumeral arthrosis, glenohumeral arthritis or systemic disorders predisposing for arthritis
• a central component of pain perception manifested by radiating pain in the involved limb; implying worse outcome after subacromial decompression.
• pregnancy
• breastfeeding
• reduced liver function (Increased serum bilirubin, ASAT or ALAT), decompensated heart failure (NYHA class 3-4)
• increased intracranial pressure or disease of the central nervous system (CNS)
• chronic alcoholism
• epilepsy
• psychiatric disease, increased intraocular pressure
• acute intermittent porphyria
• hyperthyroidism
• use of thyroid hormones
• upper respiratory tract infections
• pneumonia
• intracranial lesions
• acute head injuries
• ocular injuries
• hydrocephalus
• risk factors predisposing for intra-articular bleeding
• increased risk of infection

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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14 participants in 2 patient groups, including a placebo group

Ketalar

Experimental group

Description:

ketalar injection, subacromial

Treatment:

Drug: Ketalar

Drug: NaCl 9%

Placebo

Placebo Comparator group

Description:

physiological sodium chloride (NaCl 9%) injection, subacromial

Treatment:

Drug: Ketalar

Drug: NaCl 9%