A 72-year-old female with past medical history of hypertension and type-II diabetes mellitus presents to the ambulatory clinic complaining of right shoulder pain four months after having a left middle cerebral artery stroke. She reports moderate pain and stiffness in the right shoulder, and describes the pain as a dull ache that is present at rest and worse with shoulder abduction. She has no prior history of shoulder pain. On exam, the patient has right sided hemiplegia, increased tone in the pectoralis and subscapularis muscles, with adduction and internal rotation of the right arm and shoulder. Modified Ashworth Scale is 2/4 with arm abduction and external rotation. The patient has restricted passive external rotation of the right arm to 45 degrees, compared with 90 degrees on the left. The shoulder pain is exacerbated when trying to put her right hand behind her neck. She has no allodynia or changes in temperature sensation.

 
Questions

1. If the patient described above had pain originating at the shoulder status post stroke, what typical symptoms would you expect? What signs and symptoms are less likely to be because of the stroke?

Signs and symptoms of shoulder pain after stroke include:

• Stiffness
• Pain with motion (especially abduction)
• Shoulder drooping (due to subluxation)
• Spasticity of the SITS (supraspinatus, infraspinatus, teres minor, subscapularis) muscles, most frequently with a pattern of internal rotation, adduction of the shoulder, and flexion at the elbow¹
• Numbness
• Tingling
• Asymmetry
• Swelling
• Tenderness
• Decreased range of motion²
  

Signs and symptoms that are less likely to be from the stroke include:

• Sudden onset shoulder/arm pain along with sudden onset chest pain points toward a cardiac etiology and myocardial infarction must be on the differential
• Sudden onset pulling sensation of the shoulder along with respiratory distress points toward a pulmonary embolism
• Shoulder pain in the setting of a cough should trigger workup for pneumonia and lung cancer
• Masses felt around the shoulder on palpation are less likely to be present status post stroke and more likely to be of tumor etiology³
  

2. What proportion of stroke survivors suffer from hemiplegic shoulder pain?

As the most common pain disorder after stroke, many studies have aimed to quantify the incidence of hemiplegic shoulder pain in stroke patients. The range reported in the literature is from 16-84%, with most widely accepted to be around 70%.

One of the earliest studies to quantify this included 50 patients with hemiplegia following stroke, and found that 36 had shoulder pain (72%), and that range of shoulder external rotation was significantly related.⁴ This finding was supported by a prospective longitudinal study that found 72% of patients with hemiplegia after stroke (n=219) experienced HSP at least once over the course of one year, which occurred much more in patients with spasticity than flaccidity (85% vs 18%).⁵ In comparison, a more recent prospective population based study of 301 patients who had had strokes found that 10% reported shoulder pain at baseline, which had increased to 29% at a 12-month follow-up, with peak onset and severity at four months.⁶

The range of incidence reported in the literature is likely related to the nonuniform onset of HSP and the varying time course, as well as the way in which the pain is measured, either with movement or at rest.

3. The patient above asks why she has pain after the stroke. What do you tell her?

There are a variety of factors and pathologies contributing to the presence of shoulder pain after stroke. These can be broadly divided into neurologic and mechanical categories. Neurologic factors involve injury to the nerves, such as with a brachial plexus injury, muscle spasticity or weakness, and sensitization of the nervous system to pain signals. Mechanical factors involve injury to the muscles, bones, and structures that make up the shoulder joint, such as a subluxation, adhesive capsulitis, or injury to the muscles that make up the rotator cuff.⁷ The shoulder stabilizes the supraspinatus and deltoid muscles, so if the shoulder is injured, these muscles will be affected. Patients have a mix of these categories, which overall decreases the stability of the shoulder complex and leads to a painful condition.

Based on this patient’s presentation and time since her injury, the largest contributor to her shoulder pain is most likely her spasticity. Studies have shown that there is a much higher proportion of patients with spastic hemiplegia who experience shoulder pain versus those with flaccid hemiplegia (85 vs 18%)⁵. Additionally, the loss of motor function due to increased tone in the adductor muscles may also have led to a component of shoulder impingement and muscle strain or contractures which are also contributing to her pain.⁸

4. How do you diagnose hemiplegic shoulder pain after a stroke? What tests can you do?

The diagnosis of HSP is a typically a clinical one, primarily based on the history and physical exam. Clarifying the patient’s history of shoulder pain prior to the stroke, any history of trauma, or surgeries to the shoulder are all very important. All evaluations should start with a thorough shoulder examination, including passive and active range of motion, strength testing, sensation, reflexes, and glenohumeral joint instability, with comparison to the unaffected side. Noting the patient’s strength and sensation will help in determining the etiology by characterizing it as central, peripheral, focal, or diffuse.⁷ Grading any spasticity that is present is also very important in patients with post-stroke hemiplegia.

When performing the physical exam, certain maneuvers have been found to be predictive of HSP. A study by Rajaratnam et al investigating physical exam findings in 135 acute post-stroke patients, including 30 with shoulder pain at rest, found that there were three maneuvers that when positive, successfully predicted presence of HSP. These were the Neer test, hand-behind-neck, and a difference in passive external rotation of greater than 10 degrees compared to the unaffected shoulder (sensitivity 96.7%, specificity 99%).⁹

Ryerson and Levit developed a categorization system for HSP to assist with differentiating causes that are intrinsic to the shoulder joint itself versus outside the shoulder complex. The four categories they identified were as follows:¹⁰

1. Joint pain
2. Muscle pain
3. Altered sensitivity
4. CRPS-1
   

This framework can be useful to keep in mind when examining a patient with suspected HSP to identify what factors are most heavily contributing to the presentation and potentially tailor treatment to musculoskeletal or nervous system dysfunction. Beyond the history and physical exam, diagnostic imaging can also be used to help elicit underlying contributors to the HSP. X-ray, MRI, and ultrasound can all be used to identify pathologic features and guide treatment.

5. What initial treatment options would you recommend for this patient?

The initial treatment option depends on the root cause of the shoulder pain. Below is a list of common initial treatment options, depending on the cause of the shoulder pain after stroke.

1. Poor positioning/immobility of the shoulder for many days/weeks:

• In a double-blind, randomized, placebo-controlled study published in 2017, Kinesio taping (worn for three weeks) was shown to have greater reductions in shoulder pain and improvement in shoulder flexion, external, and internal rotation.¹¹ Positioning techniques such as wheelchair arm supports, pillows, and slings are also effective. Massage therapy, acupuncture, and ROM exercises have also shown to improve shoulder pain.

2. Frozen Shoulder (adhesive capsulitis):

• Anti-inflammatory medications to help reduce swelling and inflammation
• Physical therapy targeted at full ROM exercises: Spencer osteopathic manipulative technique¹²
• Heat/ice
• Steroid injections for short term pain relief in the first four to six weeks¹³ 
• Calcitonin: stimulates the release of endorphins¹³

3. Subluxation:

• Heat/ice
• Rest for four weeks
• Sling for comfort
• Avoid pushing/pulling exercise; avoid abduction beyond 90 degrees
• PT after four weeks of rest¹⁴

4. Spasticity:

• Medications commonly used: baclofen, dantrolene, and tizanidine
• Braces/splints
• Physical therapy
• Toxin injections^15,16

5. Neuropathy:

• Topicals: lidocaine patches
• Medications: pregabalin (Lyrica), gabapentin, amitriptyline, nortriptyline, desipramine, duloxetine
• Other therapies: isosorbide dinitrate spray, transcutaneous electrical nerve stimulation, complementary and alternative medicine therapies, relaxation techniques, like yoga, non-prescription hand and foot braces, orthotics.¹⁷

6. If initial conservative treatment options fail, what interventions would like to do for this patient?

If none of the rehabilitation and compensation techniques mentioned above provide relief, surgery may be recommended and is typically used as a last resort. If the patient has adhesive capsulitis, the goal of surgery is to stretch and release the stiffened joint capsule. Surgery for a subluxation would be done to repair ligaments, tendons, and bony fractures that may have occurred during the injury. Given that this patient is presenting with significant spasticity involving her internal rotators, she might benefit from surgical treatment if nerve blocks to the affected muscles have not been successful. Surgeries for spasticity would include placing an intrathecal baclofen pump or selective dorsal rhizotomy that rebalances electrical signals sent to the spinal cord by cutting select nerve roots. For a patient with neuropathy of the shoulder, surgery would oftentimes focus on suprascapular nerve release.¹⁸

References

1. Hefter H, Jost WH, Reissig A, et al. Classification of posture in poststroke upper limb spasticity: a potential decision tool for botulinum toxin A treatment? Int J Rehabil Res. 2012;35(3):227-233. https://doi.org/10.1097/MRR.0b013e328353e3d4. 

2. Treister AK, Hatch MN, Cramer SC, et al. Demystifying post-stroke pain: from etiology to treatment. PMR. 2017;9(1):63-75. https://doi.org/10.1016/j.pmrj.2016.05.015.   

3. Torres-Parada M, Vivas J, Balboa-Barreiro V, et al. Post-stroke shoulder pain subtypes classifying criteria: towards a more specific assessment and improved physical therapeutic care. Braz J Phys Ther. 2020;24(2):124-134. https://doi.org/10.1016/j.bjpt.2019.02.010. 

4. Bohannon RW, Larkin PA, Smith MB, et al. Shoulder pain in hemiplegia: statistical relationship with five variables. Arch Phys Med Rehabil. 1986;67(8):514-516.

5. Van Ouwenaller C, Laplace PM, Chantraine A. Painful shoulder in hemiplegia. Arch Phys Med Rehabil. 1986;67(1):23-26.

6. Adey-Wakeling Z, Arima H, Crotty M, et al. Incidence and associations of hemiplegic shoulder pain poststroke: prospective population-based study. Arch Phys Med Rehabil. 2015;96(2):241-247.e1. https://doi.org/10.1016/j.apmr.2014.09.007. 

7. Vasudevan JM, Browne BJ. Hemiplegic shoulder pain: an approach to diagnosis and management. Phys Med Rehabil Clin N Am. 2014;25(2):411-437. https://doi.org/10.1016/j.pmr.2014.01.010. 

8. Wilson RD, Chae J. Hemiplegic Shoulder Pain. Phys Med Rehabil Clin N Am. 2015;26(4):641-655. https://doi.org/10.1016/j.pmr.2015.06.007. 

9. Rajaratnam BS, Venketasubramanian N, Kumar PV, et al. Predictability of simple clinical tests to identify shoulder pain after stroke. Arch Phys Med Rehabil. 2007;88(8):1016-1021. https://doi.org/10.1016/j.apmr.2007.05.001.   

10. Ryerson S, Levit K. The Shoulder in Hemiplegia. In: Donatelli RA, ed. Physical Therapy of the Shoulder (Fourth Edition). Churchill Livingstone; 2004:263-288. https://doi/org/10.1016/B978-044306614-6.50011-9. 

11. Huang YC, Chang KH, Liou TH, et al. Effects of Kinesio taping for stroke patients with hemiplegic shoulder pain: A double-blind, randomized, placebo-controlled study. J Rehabil Med. 2017;49(3):208-215.  https://doi.org/10.2340/16501977-2197. 

12. Phansopkar P, Qureshi MI. An Integrated Physical Therapy Using Spencer’s Technique in the Rehabilitation of a Patient With a Frozen Shoulder: A Case Report. Cureus. 2023;15(6):e41233. https://doi.org/10.7759/cureus.41233.

13. Treatment Strategy for Frozen Shoulder. Clin Orthop Surg. 2019;11(3):249-257. https://doi.org/10.4055/cios.2019.11.3.249. 

14. Misamore GW, Sallay PI, Didelot W. A longitudinal study of patients with multidirectional instability of the shoulder with seven- to ten-year follow-up. J Shoulder Elbow Surg. 2005;14(5):466-470. https://doi.org/10.1016/j.jse.2004.11.006.  

15. Jacinto J, Camões-Barbosa A, Carda S, et al. A practical guide to botulinum neurotoxin treatment of shoulder spasticity 1: Anatomy, physiology, and goal setting. Frontiers in Neurology. 2022;13. https://doi.org/10.3389/fneur.2022.1004629. 

16. Hecht JS. Subscapular nerve block in the painful hemiplegic shoulder. Arch Phys Med Rehabil. 1992;73(11):1036-1039.

17. Bates D, Schultheis BC, Hanes MC, et al. A Comprehensive Algorithm for Management of Neuropathic Pain. Pain Med. 2019;20(Suppl 1):S2-S12. https://doi.org/10.1093/pm/pnz075. 

18. Ghodadra N, Nho SJ, Verma NN, et al. Arthroscopic decompression of the suprascapular nerve at the spinoglenoid notch and suprascapular notch through the subacromial space. Arthroscopy. 2009;25(4):439-445. https://doi.org/10.1016/j.arthro.2008.10.024.