Comparing the Efficacy of Intra-articular Platelet-Rich Plasma, and Corticosteroid Injections in the Management of Frozen Shoulder: A Randomized Controlled Trial

Comparison of the effectiveness of intra-articular injection of platelet-rich plasma and corticosteroid in the treatment of frozen shoulder

Phase 3 parallel group randomized single-blinded clinical trial with two intervention groups, on 80 patients. The rand function of Excel software was used for randomization.

Patients referred to Qaem Hospital or a specialist doctor's office in Mashhad diagnosed with frozen shoulder, were treated using intra-articular injection by a shoulder surgeon in two randomly assigned groups (1. local PRP; and 2. local corticosteroid). Patients are followed up 0, 3, 6, 12, and 24 weeks post-injection. This study is single-blinded (analysts, allocation of sample data to groups).

Inclusion criteria: Unilateral shoulder pain and limited range of motion for more than one month, age over 18 years, shoulder pain for at least one month with more than one-third loss of active shoulder flexion abduction and external rotation, normal glenohumeral joint radiograph, consent to participate. Exclusion criteria: Previous shoulder trauma, chronic diseases, diabetes, malignancy, pregnancy, breastfeeding, hematologic disorders, steroid sensitivity, antitumor or immunosuppressive drugs, shoulder corticosteroid injections within the last 6 months, local shoulder infection, systemic infection, or inflammatory disease, under antiplatelet or anticoagulant treatment, unwillingness to participate.

Intervention treatment group 1: 40 patients with frozen shoulder and treatment using 8 ml of topical PRP Intervention treatment group 2: 40 patients with frozen shoulder and treatment using 40 mg/ml two cc vials, equivalent to 80 mg of corticosteroid (methylprednisolone) and 6 cc of topical lidocaine.

VAS; ROM; SPADI; and Quick DASH questionnaires.

Randomization type: simple individual The random assignment of eligible people to the study is done by a person who is independent of the research team and is not involved in the treatment process, participant follow-up, data collection, and recording. To achieve an equal number of patients in the groups under study and the least amount of difference in the number of people participating in the groups, randomization of the group is done through random numbers generated by the computer by a researcher who does not have a clinical company in the present analysis. Individuals with odd numbers are assigned to group I (PRP) and individuals with even numbers are assigned to group II (steroids). The study is designed as a study of two groups 1:1. Allocation Concealment method: The belonging of people/patients to the groups under study will be secret for the patient, doctor/interventionist, and the person evaluating the results so that the first 80 envelopes containing a card with a letter label indicating the belonging of the patients to the groups under study will be prepared and given inside opaque envelopes. These envelopes are placed by the secretary of the department, who is not involved in research and recording the outcomes under study. Data before and after the injection process will be collected and recorded by people other than the surgeon.

In this study, the analysts and allocators of the samples are blinded to the groups, and the people with other responsibilities are aware of how the groups are assigned.