Background and Goal of Study: 
Chronic shoulder pain (CSP) can be secondary to multiple musculoskeletal disorders, such as adhesive capsulitis, arthrosis, frozen shoulder, acromioclavicular joint syndrome, rotator cuff tendinopathy and fullthickness rotator cuff tears. To provide pain relief and to facilitate functional rehabilitation of patients suffering CSP, suprascapular nerve block (SSNB) can be made as a useful treatment. The objective of our study is to retrospectively evaluate the analgesic effect of SSNB with local anesthetics combined with corticoids and pulsed radiofrequency (PRF). 

Materials and Methods: 
We studied retrospectively a cohort of 50 consecutive patients receiving suprascapular nerve block for chronic shoulder pain between January 2014 and January 2017. Ultrasound-guided SSNB was performed with a mixture of ropivacaine 0,2% (4ml) + triamcinolone 40mg and PRF for 240 seconds. We evaluate demographic characteristics and Numerical Rating Scale (NRS) before and after nerve block at 1 month and 3 months. We consider significant pain relief if reduction of NRS is >30%. 

Results and Discussion: 
Demographic characteristics; mean age 76±3 years old, 82% of women and 18% men. The mean NRS score of 50 patients before technique was 7,8±0,3. The mean NRS scores at 1-month were 4,3±0,7 (NRS>45% mean reduction), 34 (68%) patients had significant pain relief with mean NRS 3±0.55. At 3-month follow-up NRS was 5,4±0,8, from them 24 patients (48%) still had significant pain relieve with mean NRS 2.9±0.76. No adverse side effects were observed.
Results shows that SSNB may be a treatment approach for patients suffering CSP providing a significant pain relief in 68% of patients at 1-month and 48% at 3-months. SNB effect is short-lived showing an increase in mean NRS score at 3-months. 

Conclusions: 
The use of SSNB with local anesthetics and corticoids combined with PRF achieves a reduction of NRS for 12 weeks in our patients with no complications reported. However, we cannot conclude that it was the corticoid or PRF that caused the improvement. With this result we are starting a clinical assay comparing SSNB with corticoids versus PRF to conclude if we can avoid corticoid treatment to prevent its adverse effects. 

References: 
Liu A, Zhang W, Sun M, Ma C, Yan S. Evidence-based Status of Pulsed Radiofrequency Treatment for Patients with Shoulder Pain: A Systematic Review of Randomized Controlled Trials. Pain Practice, 16, 4 (2016) 518-525


02 / Suprascapular block for chronic shoulder pain, retrospective evaluation of results