Overview
Shoulder surgery — particularly rotator cuff repair — is associated with some of the most severe postoperative pain in elective orthopaedic surgery. Up to 70% of patients experience severe pain in the first 24 hours. Pain arises from the complex innervation of the shoulder joint, primarily the suprascapular nerve (~70% of articular innervation) and the axillary nerve (~30%), with contributions from the lateral pectoral, subscapular, and musculocutaneous nerves.
The main clinical challenge is managing two distinct pain phases: intense early pain (0–12h, well-controlled by regional blocks) and the rebound pain phenomenon (12–24h) when the block wears off. Adequate oral multimodal analgesia must be established before block offset to prevent this spike.
PROSPECT 2019 summary (Toma et al., Anaesthesia 2019): Paracetamol + NSAIDs + IV dexamethasone as basic multimodal analgesia. Interscalene block (ISB) is first-choice regional technique — continuous ISB favoured over single-shot for major procedures. Suprascapular nerve block ± axillary nerve block as motor-sparing alternative. Arthroscopic technique preferred over open when surgically appropriate. Opioids as rescue only.
Analgesic Pathway
- Paracetamol 1g PO
- COX-2 inhibitor (e.g. celecoxib 200 mg PO)
- ISB or SSNB + axillary nerve block pre-op
- Gabapentin 300 mg — selected patients (chronic pain, opioid tolerant)
- GA or regional (ISB alone for arthroscopic)
- Dexamethasone 8 mg IV
- Paracetamol 1g IV (if not given pre-op)
- Arthroscopic approach preferred where possible
- Continuous ISB catheter — major open procedures
- Intraarticular steroid injection — insufficient evidence
- Paracetamol 1g QDS regular
- NSAID / COX-2 regular (≤5 days)
- Opioid PRN rescue (oxycodone 5–10 mg)
- Oral analgesia established BEFORE block wears off
- Cryotherapy to shoulder
- Intraarticular local anaesthetic — limited evidence
✓ Recommended | ◎ Optional/conditional | ✗ Not recommended. Based on PROSPECT 2019.
Systemic Analgesia
Paracetamol + NSAIDs/COX-2 + IV dexamethasone perioperatively. Regular dosing is critical — must be established before the nerve block wears off to prevent rebound pain. Dexamethasone extends block duration by 6–8h and reduces opioid requirements.
| Agent | Dose | Route | Frequency | Notes |
|---|---|---|---|---|
| Paracetamol | 1 g | IV/PO | QDS | Regular throughout — not PRN |
| Celecoxib | 200 mg | PO | BD | COX-2 preferred — less GI risk; ≤5 days |
| Ibuprofen | 400 mg | PO | TDS | Non-selective NSAID; add PPI |
| Dexamethasone | 8 mg | IV | Single intraop | Extends ISB duration by 6–8h; antiemetic |
| Oxycodone IR | 5–10 mg | PO PRN | 4–6h | Rescue only — avoid regular prescription |
Regional Analgesic Strategy
Regional analgesia is essential for shoulder surgery — systemic analgesia alone is insufficient for the first 12–24h. The choice of block depends on the procedure complexity, respiratory reserve, and whether motor sparing is required.
Interscalene Block (ISB)
PROSPECT ✓ First-lineGold standard for shoulder analgesia. Blocks C5–C6 (and often C7) — excellent coverage for rotator cuff, arthroplasty, and open shoulder surgery. Phrenic nerve palsy inevitable.
Suprascapular + Axillary Nerve Block
PROSPECT ✓ AlternativeMotor-sparing alternative to ISB. SSNB blocks ~70% of shoulder innervation; adding axillary nerve block provides more complete coverage. No phrenic nerve palsy.
Continuous ISB Catheter
PROSPECT ✓ Major proceduresPROSPECT favours continuous ISB over single-shot for major open procedures. Provides sustained analgesia over 48–72h, avoiding rebound pain. Requires catheter management skills.
ISB contraindicated in: Contralateral phrenic nerve palsy · contralateral pneumonectomy · severe respiratory disease (FEV₁ <50%) · bilateral block intended. In these patients, use suprascapular + axillary nerve block combination instead — equivalent analgesia without respiratory compromise.
Interscalene Block (ISB)
Anatomy
The interscalene block targets the brachial plexus at the level of the trunks (C5–C7), between the anterior and middle scalene muscles. At this level, C5 and C6 are most reliably blocked — providing complete shoulder coverage. The phrenic nerve (C3–5) runs on the anterior scalene and is blocked in virtually 100% of cases, causing ipsilateral hemidiaphragm palsy.
Technique — Ultrasound-Guided
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Position & probe placement
Patient supine or semi-recumbent, head turned 45° away. Linear probe (10–15 MHz) placed transversely in the posterior triangle of the neck at the level of the cricoid cartilage. Identify the sternocleidomastoid (SCM) anteriorly and the scalene muscles.
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Identify the plexus
Between the anterior and middle scalene muscles, the brachial plexus roots/trunks appear as 2–3 hypoechoic oval structures (a "traffic light" appearance at C5–C6 level). The carotid artery is medial — confirm with Doppler.
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In-plane needle insertion — posterior to anterior
Insert the needle posteriorly, advance in-plane through the middle scalene into the interscalene groove. Target the C6 root (middle of the "traffic light"). Aspirate before each injection.
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Injection
Inject 10–20 mL in 5 mL increments. Observe spread surrounding C5 and C6 roots. Injection pressure monitoring recommended — stop if high pressure (possible intraneural injection).
Dosing
| Agent | Concentration | Volume | Onset | Duration | Notes |
|---|---|---|---|---|---|
| Ropivacaine | 0.5% | 15–20 mL | 10–20 min | 10–16 h | Standard single-shot choice |
| Ropivacaine | 0.375% | 15–20 mL | 15–25 min | 8–14 h | Lower concentration — less motor block |
| Bupivacaine | 0.5% | 10–15 mL | 15–25 min | 14–20 h | Longer duration; reduce volume in elderly |
| Levobupivacaine | 0.5% | 10–15 mL | 15–25 min | 14–20 h | Preferred over bupivacaine in frail patients |
Continuous catheter infusion: Ropivacaine 0.2% at 5–10 mL/h ± 5 mL bolus PRN. IV dexamethasone 8 mg extends single-shot duration by 6–8h.
Suprascapular + Axillary Nerve Block
The combination of suprascapular nerve block (SSNB) + axillary nerve block (ANB) is recommended when ISB is contraindicated (respiratory disease, contralateral phrenic palsy) or when motor sparing is a priority. Provides analgesia without phrenic nerve involvement.
Suprascapular Nerve Block — Dosing
Target: suprascapular notch or spinoglenoid notch (posterior approach, ultrasound-guided). The suprascapular nerve supplies ~70% of shoulder joint innervation.
| Agent | Concentration | Volume | Duration | Notes |
|---|---|---|---|---|
| Ropivacaine | 0.5% | 10 mL | 8–14 h | Standard; supraspinous fossa approach |
| Bupivacaine | 0.5% | 10 mL | 12–18 h | Longer duration — useful for overnight analgesia |
Axillary Nerve Block — Dosing
Target: posterior aspect of the surgical neck of humerus or quadrilateral space. Provides coverage of the deltoid and inferior shoulder capsule (~30% of innervation).
| Agent | Concentration | Volume | Duration |
|---|---|---|---|
| Ropivacaine | 0.5% | 10 mL | 8–14 h |
| Bupivacaine | 0.5% | 10 mL | 12–18 h |
Managing Rebound Pain
Rebound pain occurs in 40–80% of patients after single-shot ISB for shoulder surgery — typically at 12–18h when the block wears off. Pain can be severe and difficult to manage. It is caused by the abrupt transition from complete sensory blockade to full afferent input, combined with central sensitisation during surgery.
Prevention strategy
- Start oral multimodal analgesia before block wears off — paracetamol + NSAID should be given intraoperatively and regular doses scheduled for that evening
- IV dexamethasone 8 mg — extends block by 6–8h, giving more time for oral analgesia to take effect
- Continuous ISB catheter for major procedures — eliminates rebound altogether
- Patient education — warn patients that severe pain is possible as the block wears off; ensure rescue opioid prescription available at home
- Gabapentinoids (selected patients only) — some evidence for attenuating rebound pain in opioid-tolerant or chronic pain patients
Not Recommended
Limited and inconsistent evidence. Short duration of action, chondrotoxicity concerns with certain agents (especially bupivacaine). Not recommended as routine.
Insufficient evidence for postoperative pain benefit after shoulder surgery to justify routine use.
Insufficient evidence for routine use in all patients. May be considered in selected patients (chronic pain, opioid-tolerant) but not recommended universally. Sedation and dizziness risk significant.
Bilateral interscalene blocks cause bilateral phrenic nerve palsy — severe respiratory compromise and potential respiratory failure. Absolutely contraindicated. Use alternative techniques for contralateral shoulder.
Practical Analgesic Protocol
References
- Toma O, Persoons B, Pogatzki-Zahn E, Van de Velde M, Joshi GP; PROSPECT Working Group. PROSPECT guideline for rotator cuff repair surgery: systematic review and procedure-specific postoperative pain management recommendations. Anaesthesia. 2019;74(10):1320–1331. PMID 31468551 ↗
- ESRA PROSPECT. Rotator Cuff Repair Surgery 2019. esraeurope.org ↗
- Hussain N, Brull R, McCartney CJL, et al. Phrenic nerve block complication rate with interscalene brachial plexus block: a systematic review. Anesth Analg. 2021;132(3):702–710.
- Desmet M, Braems H, Reynvoet M, et al. IV and perineural dexamethasone are equivalent in increasing the analgesic duration of a single-shot interscalene block with ropivacaine for shoulder surgery: a prospective, randomized, placebo-controlled study. Br J Anaesth. 2013;111(3):445–452.
- Abdallah FW, Halpern SH, Aoyama K, Brull R. Will the real benefits of single-shot interscalene block please stand up? A systematic review and meta-analysis. Anesth Analg. 2015;120(5):1114–1129.
- Wiegel M, Gottschaldt U, Hennebach R, et al. Complications and adverse effects associated with continuous peripheral nerve blocks in orthopaedic patients. Anesth Analg. 2007;104(6):1578–1582.
- Olausson A, Naucler E, Lundblad M, et al. Rebound pain after single-shot peripheral nerve block. Reg Anesth Pain Med. 2022;47(10):614–623.