Efficacy of Suprascapular Nerve Block on the Tolerability and Effectiveness of Shoulder Hydrodistension in Patients With Adhesive Capsulitis: A Randomized Clinical Trial
Phase: NA
Conditions: Adhesive Capsulitis, Adhesive Capsulitis of Unspecified Shoulder, Adhesive Capsulitis, Shoulder, Frozen Shoulder, Shoulder Pain, Shoulder Stiffness
Sponsor: Universidade do Porto

Protocol -  Approval  15/1/2026 
 
Eﬃcacy of suprascapular nerve block on the tolerability and eﬃcacy of shoulder 
hydrodistension in paƟents with adhesive capsuliƟs: randomizes clinical trial 
________________________________________ 
2. Principal InvesƟgator 
Name: João Paulo Castro 
Contact: jpcastro@med.up.pt 
 
Under the supervision of: 
Professor José Paulo Andrade 
Full Professor at the Faculty of Medicine of the University of Porto 
Professor Iva Brito 
Senior Consultant in Rheumatology at the Local Health Unit of São João EPE and Invited 
Professor at the Faculty of Medicine of the University of Porto 
 
Porto – January 2026 
 
IdenƟﬁcaƟon of the Research Unit 
Physical Medicine and RehabilitaƟon Service of the Local Health Unit of São João, EPE 
________________________________________ 
3. ScienƟﬁc jusƟﬁcaƟon and context 
Adhesive capsuliƟs of the shoulder is a frequent pathology, characterized by pain and 
progressive limitaƟon of joint mobility, with a signiﬁcant impact on the quality of life and 
funcƟonality of paƟents (1). Shoulder joint hydrodistension is considered one of the treatments 
of choice, demonstraƟng eﬀecƟveness in reducing pain and improving range of moƟon. 
However, the procedure can be painful, which may limit its tolerability and potenƟally the 
therapeuƟc aggressiveness required for eﬀecƟve capsular distension (2, 3). 
 
Suprascapular nerve block, using local anestheƟcs such as ropivacaine, is a known technique 
for controlling shoulder pain (4, 5). Its use prior to hydrodistension may: 
• Reduce pain during the procedure 
• Improve paƟent tolerance 
• Allow greater capsular distension 

• PotenƟally improve clinical outcomes and prognosis 
To date, there is limited and heterogeneous evidence on the impact of this block as an adjunct 
to hydrodistension, jusƟfying the performance of this clinical trial. 
 
________________________________________ 
4. Study ObjecƟves 
Main ObjecƟve 
To evaluate the evoluƟon of shoulder pain and mobility in paƟents with adhesive capsuliƟs 
undergoing hydrodistension, with or without suprascapular nerve block. 
 
Pain will be assessed using the Numerical Pain Scale (NRS), and shoulder mobility will be 
assessed by goniometry of joint ranges of moƟon. 
 
Assessments will be conducted at three points in Ɵme: 
• Before the procedure (baseline) 
• 1 month aŌer the procedure 
• 3 months aŌer the procedure 
Secondary objecƟves 
To evaluate the impact of the intervenƟon on psychological, funcƟonal, and quality of life 
dimensions, namely: 
• Anxiety and depression, assessed using the Hospital Anxiety and Depression Scale (HADS) 
• Kinesiophobia, assessed using the Tampa Scale for Kinesiophobia 
• Health-related quality of life, assessed using the EQ-5D-5L 
• Upper limb funcƟonality, assessed using the QuickDASH and the Shoulder Pain and Disability 
Index (SPADI) 
These variables will be assessed at two points in Ɵme: 
• Baseline 
• 3 months aŌer the procedure 
AddiƟonally, the need for physiotherapy and its duraƟon aŌer the procedure will be evaluated. 
 
________________________________________ 
5. Study Design 
• ProspecƟve clinical trial 

• Randomized 
• Two parallel arms 
• Open-label 
• Single intervenƟon 
________________________________________ 
6. Study PopulaƟon 
Inclusion Criteria 
• Adults ≥ 18 years 
• Clinical diagnosis of adhesive capsuliƟs of the shoulder 
• Persistent pain and funcƟonal limitaƟon despite iniƟal conservaƟve treatment 
• Ability to understand and sign informed consent 
Exclusion Criteria 
• Known allergy to ropivacaine or methylprednisolone 
• AcƟve local or systemic infecƟon 
• Uncontrolled coagulopathy or anƟcoagulaƟon 
• Recent prior surgery of the aﬀected shoulder 
• Neurological disease aﬀecƟng the upper limb 
• Pregnancy 
 
Sample size (calculaƟon and assumpƟons) 
Proposed primary endpoint: pain and mobility 3 months aŌer hydrodistension (Numerical Pain 
Scale, NRS 0–10). 
Clinical hypothesis: suprascapular nerve block reduces pain during the procedure. 
AssumpƟons for calculaƟon (conservaƟve and clinically plausible): 
• Clinically relevant minimum diﬀerence (Δ): 2 points on the VAS 
• Standard deviaƟon (SD): 2.5 (typical variability in procedural pain) 
• Two-tailed test, α = 0.05; Power (1−β) = 80% 
 
Result of the calculaƟon (comparison of means, 2 groups): 
• Approximately 25 parƟcipants per group are needed (total 50) 
Adjustment for losses/dropouts (≈15%) 

• 25 / (1−0.15) ≈ 29.4 → rounding: 30 per group 
• Proposed ﬁnal sample size: 60 parƟcipants (30+30) 
________________________________________ 
7. RandomizaƟon 
ParƟcipants will be randomly assigned in a 1:1 raƟo to: 
• Control Group: Isolated hydrodistension 
• IntervenƟon Group: Suprascapular nerve block followed by hydrodistension 
RandomizaƟon will be performed using a previously generated random sequence. 
 
________________________________________ 
8. IntervenƟons 
8.1 Shoulder Hydrodistension (both groups) 
Performed anteriorly, with intracapsular injecƟon of: 
• 20 ml of saline soluƟon 
• 4 ml of ropivacaine 
• 40 mg of methylprednisolone 
________________________________________ 
8.2 Suprascapular Nerve Block (intervenƟon group) 
Performed prior to hydrodistension, consisƟng of an injecƟon of: 
• 5 ml of ropivacaine 
The block will be performed in the suprascapular notch, on the posterior aspect of the 
shoulder, according to a standardized technique. 
 
There will be no sham intervenƟon. 
 
________________________________________ 
9. Concomitant Treatments 
Physiotherapy aŌer the procedure is permiƩed and not restricted by the protocol. In general, 
the duraƟon of physiotherapy is expected to be shorter aŌer eﬀecƟve hydrodistension. 
 
________________________________________ 
10. Outcome EvaluaƟon 

EvaluaƟon Times 
Outcomes will be evaluated at three disƟnct Ɵmes: 
• Before the procedure (baseline) 
• 1 month aŌer the procedure 
• 3 months aŌer the procedure 
Pain during the procedure will be evaluated exclusively at the Ɵme of the clinical act. 
 
Primary Outcome 
• Pain and mobility, assessed using the Numerical Pain Scale (NRS, 0–10), 3 months aŌer 
hydrodistension. 
 
Pain 
• Shoulder pain at rest and/or with movement, as assessed by the Numerical Pain Scale (NRS) 
• Assessed at baseline, 1 month, and 3 months 
 
Shoulder Mobility 
• Assessment of joint range of moƟon (ﬂexion, abducƟon, external rotaƟon, and internal 
rotaƟon), measured by goniometry 
• Assessed at baseline, 1 month, and 3 months 
 
Secondary Outcomes 
Shoulder and Upper Limb FuncƟonality 
• Shoulder Pain and Disability Index (SPADI) 
• Quick Arm, Shoulder, and Hand DisabiliƟes (QuickDASH) 
• Assessed at baseline and at 3 months 
 
Health-Related Quality of Life 
• Assessed using the EQ-5D-5L 
• Assessed at baseline and at 3 months 
 
Psychological Dimension 
• Anxiety and depression, assessed using the Hospital Anxiety and Depression Scale (HADS) 

• Kinesiophobia, assessed using the Tampa Scale for Kinesiophobia 
• Assessed at baseline and at 3 months 
 
Physical Therapy 
• Need for physical therapy aŌer the procedure (yes/no) 
• DuraƟon of physical therapy, measured in number of sessions or weeks of treatment 
 
Safety 
• SystemaƟc recording of adverse events, including: 
o Prolonged pain 
o Hematoma 
o InfecƟon 
o Transient or persistent neurological deﬁcit 
o Adverse reacƟons to the drugs used 
Adverse events will be classiﬁed according to severity, causal relaƟonship with the procedure, 
and need for addiƟonal intervenƟon. 
 
________________________________________ 
11. Safety and Risks 
Risks of hydrodistension 
• Transient pain 
• Hematoma 
• InfecƟon (rare) 
• Adverse drug reacƟons 
AddiƟonal risks of suprascapular block 
• Local pain or discomfort 
• Hematoma 
• Transient numbness or weakness of the shoulder 
• Accidental vascular puncture 
• Adverse reacƟons to ropivacaine 
• Nerve injury (extremely rare) 

All procedures will be performed by an experienced professional, respecƟng safety and asepsis 
standards. 
 
________________________________________ 
 
12. Expected Beneﬁts 
• Possible reducƟon of pain associated with the procedure 
• Improved tolerability of hydrodistension 
• PotenƟal improvement in clinical outcomes 
• ContribuƟon to scienƟﬁc knowledge Direct individual beneﬁt is not guaranteed. 
 
________________________________________ 
13. Ethical ConsideraƟons 
• ParƟcipaƟon is voluntary 
• ParƟcipants may leave the study at any Ɵme without clinical detriment 
• The study complies with the principles of the DeclaraƟon of Helsinki 
• WriƩen informed consent will be obtained before any procedure 
________________________________________ 
14. Data ProtecƟon and GDPR 
Data will be processed in accordance with the GDPR 
ParƟcipants will be idenƟﬁed by code 
Only the research team will have access to idenƟﬁable data 
Data will be used exclusively for scienƟﬁc purposes 
ParƟcipants may exercise their legal rights over the data at any Ɵme 
The anonymity and conﬁdenƟality of parƟcipants will be safeguarded. The paƟent will be 
entered without any reference to their name. The parƟcipant number will correspond to the 
clinical informaƟon in a separate database, which will only be used for the proposed purpose, 
aŌer supervision by Master João Paulo Castro and the service director. For analysis purposes, 
the parƟcipant number will be deleted. 
 
All informaƟon entered into the database will be recorded in the medical record. 
 

Rules of Ethical Conduct and Good PracƟces will be observed to ensure compliance with the 
precepts of the DeclaraƟon of Helsinki, the ConvenƟon on Human Rights and Biomedicine, the 
guidelines of the Council for InternaƟonal OrganizaƟons of Medical Sciences, and the Guide to 
Good Clinical PracƟces. 
 
15. Data Management and PreservaƟon 
Data will be stored in a secure physical and/or digital medium for the legally required period 
and subsequently destroyed. 
 
PaƟent characterizaƟon will be performed, including demographic data, clinical symptoms and 
associated comorbidiƟes, as well as a descripƟon of the surgical techniques used and adverse 
events that occurred (Appendix 1). 
Data collecƟon will be carried out by Master João Paulo Castro, through clinical interviews and 
consultaƟon of paƟent records. 
 
StaƟsƟcal data processing will be performed by Master João Paulo Castro. According to the 
General Data ProtecƟon RegulaƟon (GDPR), data collecƟon will be carried out through 
registraƟon in a protected Excel spreadsheet, and no paƟent idenƟﬁcaƟon data will be 
transferred. Each parƟcipant will be uniquely idenƟﬁed by a code number, which will be 
subsequently deleted. 
The data will be exported in .xls and .sav formats, compaƟble with appropriate staƟsƟcal 
soŌware, i.e., R, SPSS, Stata, and MicrosoŌ Excel. 
 
16. Funding and Conﬂicts of Interest 
The study does not involve external funding or known conﬂicts of interest. 
No addiƟonal costs are foreseen for the Local Health Unit of São João, EPE, beyond the usual 
study and provision of materials recommended for the treatment of the aforemenƟoned 
pathologies. 
 
There will be no abuse of hospital resources or any others, which will be determined by the 
management of the Physical Medicine and RehabilitaƟon service. 
 
17. DisseminaƟon of results 
The results may be presented at scienƟﬁc conferences and published in indexed scienƟﬁc 
journals with an impact factor, always guaranteeing the anonymity of the parƟcipants. 
 
________________________________________ 

18. Schedule (operaƟonal esƟmate) 
Total esƟmated duraƟon: ~12 months 
1. PreparaƟon and ethical approval (Months 0–2) 
• Submission to the Ethics CommiƩee and response to any requests for clariﬁcaƟon 
• Final versions: InformaƟon/Consent Sheet, CRF (case report form) and database 
2. Recruitment and inclusion (Months 3–8) 
• ConsecuƟve screening of eligible paƟents in consultaƟon/referral 
• RandomizaƟon and performance of the procedure (block +/− hydrodistension) 
3. Clinical follow-up (Months 3–10) 
• Standardized post-procedure assessments at deﬁned Ɵmes (D0, 1 month and 3 months) 
4. StaƟsƟcal analysis and wriƟng (Months 10–12) 
• Closing the database, ﬁnal analysis, submission to congress/journal 
 
Bibliograﬁa: 
1. 
Brindisino F, Garzonio F, Turolla A, Andriesse A, Pulina F, Cucchi D, et al. PerspecƟves, 
percepƟons, and expectaƟons of subjects with frozen shoulder: a web-based Italian survey. 
Arch Physiother. 2024;14:116-30. 
2. 
Konarski A, Narayanasamy K, Coghlan J, Chung T, Andrews M, Bell S. A Double Blind 
Randomised Controlled Trial Comparing Glenohumeral CorƟsone With and Without 
HydrodilataƟon in PaƟents With Frozen Shoulder. ANZ J Surg. 2025;95(10):2162-70. 
3. 
Wang JC, Tsai PY, Hsu PC, Huang JR, Wang KA, Chou CL, et al. Ultrasound-Guided 
HydrodilataƟon With Triamcinolone Acetonide for Adhesive CapsuliƟs: A Randomized 
Controlled Trial Comparing the Posterior Glenohumeral Recess and the Rotator Cuﬀ Interval 
Approaches. Front Pharmacol. 2021;12:686139. 
4. 
Goﬃn P, Forthomme B, Lecoq JP, Benmouna K, Kaux JF, Fontaine R. EvaluaƟon of 
intensive rehabilitaƟon under conƟnuous suprascapular nerve blockade for the treatment of 
refractory adhesive shoulder capsuliƟs. Case series. Rev Esp Anestesiol Reanim (Engl Ed). 
2022;69(10):625-31. 
5. 
Sa Malheiro N, Afonso NR, Pereira D, Oliveira B, Ferreira C, Cunha AC. [Eﬃcacy of 
ultrasound guided suprascapular block in paƟents with chronic shoulder pain: retrospecƟve 
observaƟonal study]. Braz J Anesthesiol. 2020;70(1):15-21.