Shoulder pain is a common complaint over the paralytic side of stroke patients. We suggest that
ultrasound examination should be arranged for hemiplegic shoulders in the presence of pain unresponsive to
medication and physical therapy. Ultrasound-guided dual target corticosteroid injection can be introduced over
the rotator cuff interval and subdeltoid bursa in case of rotator cuff pathologies. Otherwise, suprascapular nerve
block can be performed under ultrasound guidance. Furthermore, the physician should examine whether there
is pain associated with increased spasticity, which can be managed by shock wave therapy or botulinum toxin
intra-muscular injection. Finally, if the patients have developed symptoms of complex regional pain syndrome,
ultrasound-guided cervical sympathetic ganglion block should be taken into consideration.

corticosteroid ； shock wave ； botulinum toxin

Shoulder pain is a common complaint over the paralytic side of stroke patients, with a prevalence ranging between 22% and 47% [1]. Hemiplegic shoulder pain hampers motor recovery of the affected upper extremity, leading to extended hospital stay and delayed functional independence. Based on a recent bibliometric analysis investigating the hotspots of publications for post-stoke pain [2], the largest cluster of reference co-citation analysis was labeled as “hemiplegic shoulder pain.” Likewise, the citation most pertinent to the aforementioned cluster was the article entitled “Persistent shoulder pain in the first 6 months after stroke: results of a prospective cohort study.” [3] When we used the Sigma value to identify the innovative references [3], three of the five most novel citations were relevant to post-stroke shoulder pain, which were published in journals belonging to the categories of rehabilitation and clinical neurology. Therefore, hemiplegic shoulder pain is not only a clinically important issue but also a research focus as well.

Ultrasound has become one of the most useful tools for the evaluation of shoulder pathologies [4]. A previous ultrasound study revealed that shoulders at the hemiplegic side were more likely to have tenosynovitis of the biceps long head tendon and subdeltoid bursitis, compared with the nonhemiplegic side [5]. Therefore, we suggest that ultrasound examination should be arranged for hemiplegic shoulders in the presence of pain unresponsive to medication and physical therapy. Once relevant pathologies (effusion or tendinopathy) over the biceps long head, subdeltoid bursa, and rotator cuff tendons are detected, ultrasound-guided dual target injection with 40 mg triamcinolone acetonide and 3 mL 1% lidocaine can be introduced over the rotator cuff interval and subdeltoid bursa [6]. A randomized controlled trial showed that this approach had a longer effective duration than the traditional subacromial injection for shoulder impingement syndrome [6]. Another benefit is, for sure, the simultaneous treatment of the biceps long head tendon and subdeltoid bursa, which are the two most commonly involved structures in hemiplegic shoulders.

Nevertheless, if there are no relevant pathologies identified on shoulder ultrasonography, suprascapular nerve block can be performed under ultrasound guidance, which has also been incorporated in a recent protocol for management of stiff painful shoulders after stroke [7]. According to a recent network meta-analysis investigating injection therapies for hemiplegic shoulder pain [8], suprascapular nerve block ranked first in terms of pain relief at the 4th week after intervention. The main concern of suprascapular nerve block is its short effective duration. In this sense, the physician should examine whether there is pain associated with increased spasticity. Based on another network meta-analysis investigating post-stroke spasticity management [9], the antispasticity effect of extracorporeal shock wave was comparable to botulinum toxin injection. Shock wave, as a noninvasive therapy, can be employed as the first line to decrease spasticity-related shoulder pain. If the treatment outcome is not optimal, intramuscular botulinum toxin injection can be applied subsequently. Furthermore, a previous meta-analysis also proved the benefits of intrabursal or intraarticular botulinum toxin injection for the treatment of chronic shoulder joint and myofascial pain, partly owing to the decreased release of substance P [10]. Therefore, the residual botulinum toxin solution can be administered to the subdeltoid bursa or glenohumeral joint for better pain relief.

Finally, if the patients have developed symptoms of complex regional pain syndrome, ultrasound-guided cervical sympathetic ganglion block should be taken into consideration [11,12]. Before the physician introduces the injectate underneath the prevertebral fascia overlying the longus coli muscle, the power or color Doppler mode must be turned on to scrutinize nearby neurovascular structures (e.g., vagus nerve, common carotid, and vertebral arteries). The flow diagram of interventional pain management is provided in Figure 1, which is easy to follow and facilitates early relief of hemiplegic shoulder pain.

The study was made by (1) the research funding of the Community and Geriatric Medicine Research Center, National Taiwan University Hospital, BeiHu Branch, Taipei, Taiwan; (2) Ministry of Science and Technology (MOST 106-2314-B-002-180-MY3, 109-2314-B-002-114-MY3 and 109-2314-B-002-127), and (3) Taiwan Society of Ultrasound in Medicine.

Figure 1. Flow Diagram of Interventional Management for Hemiplegic Shoulder Pain
Abbreviations: BoNT, botulinum toxin; CRPS, complex regional pain syndrome; LHBT, the long head of the biceps tendon; SASD, subacromi-
al-subdeltoid bursa.