Feasibility of Ultrasound-Guided Suprascapular Nerve Block in Improving Shoulder Motion and Pain Post-Surgery in Breast Cancer Survivors: A Randomized Control Trial

Abstract

Patients with locally advanced breast cancer post-mastectomy complain of shoulder pain and restricted shoulder movement. The role of suprascapular nerve block (SSNB) in such patients needs to be explained as it may help in improving their quality of life along with pain relief. This study aims to evaluate the effect of ultrasound-guided suprascapular nerve block (SSNB) in improving shoulder motion and pain following surgery and compare its effect with exercise group. This study is a randomized controlled trial. Forty-eight patients were enrolled in the study who were referred from the endocrine surgery department, and they were randomized into two groups. Group A underwent ultrasound-guided (USG-guided) SSNB and Group B underwent an exercise program only. Each group had 24 patients who complained of pain and restricted shoulder range of motion (ROM). The outcome measures were assessed using the Mann–Whitney test for visual analog score and unpaired t-test for shoulder ROM and Quick Disabilities of Arm, Shoulder, and Hand (Q-DASH) questionnaire score. All patients (n = 48) had modified radical mastectomy. The mean age was 44 ± 9.44 years and all were female gender. The improvement was noted in both the groups, but in intergroup comparison, Group A patients had significant improvement in VAS, Q-DASH score, shoulder flexion, and abduction immediately and at the 4th week follow-up (p = 0.001). No adverse effect was reported. A small sample size and no blinding reduce the strength of the study. USG-guided SSNB in post-mastectomy patients is proven to be an effective, safe, and economically accepted treatment for low-resource countries like India.

Breast cancer is one of the most common cancers worldwide with over 2 million cases diagnosed every year. In India, it accounts for 15.4% of all cancers and about 27.7% of all female cancers [1]. The 5-year survival rate is 89% in patients with cancer (Ca) breast with improving medical management [2].

Since advancements in treatment approach, the mortality has declined, but the morbidity related to it has increased; one of them is functional impairment of the shoulder joint which negatively hampers the quality of life (QoL) of Ca breast survivors. Surgical procedures including modified radical mastectomy (MRM) and axillary lymph node dissection (ALND) have been associated with significant post-mastectomy pain and functional impairment of the upper extremity. There was a 9% and 68% prevalence of shoulder and arm pain respectively following surgery [3–6].

The factors responsible for pain and restricted motion of the shoulder are incisional pain, strain in muscle, fear of pain during range of motion, axillary web syndrome, and post-mastectomy pain syndrome.

Pain leads to discomfort and restricted movement of the upper limb, and protective upper extremity posture leads to altered motor control adaptation which in turn causes alteration in scapulothoracic and shoulder girdle biomechanics and shoulder problems [3].

Pain control is the initial and most important step in the rehabilitation of post-mastectomy pain. The persistence of pain is the most consistent factor which leads to shoulder dysfunction and decreases the QoL of breast cancer survivors. Medications like amitriptyline, nortriptyline, gabapentin, pregabalin, and lidocaine patch have been used to relieve pain in such patients. In refractory cases, where the pain is not subsided by medication, a local nerve block can be planned [7, 8].

These are some of the nerve blocks that can be given to relieve shoulder pain: stellate ganglion block, SSNB, subacromial block, intercostal nerve block, serratus plane block, botulinum toxin injection, and cervical epidural injection [9, 10].

SSNB is one the safest intervention modalities which seems to be helpful in relieving pain in chronic shoulder pathology, adhesive capsulitis, and shoulder pain following stroke and after thoracotomy.

Suprascapular nerve block helps to relieve pain and improve shoulder mobility as it innervates 70% shoulder joint and also carries somatic afferent and autonomic fibers. The shoulder is also innervated by the axillary nerve, but due to its anatomical location, it is difficult to block it; therefore, SSNB is the nerve of choice for giving block.

Materials and Methods

A randomized controlled study was conducted at the Physical Medicine Rehabilitation Department in a tertiary care center in northern India. Forty-eight patients with known cases of Ca breast who underwent breast surgery and developed pain and restricted shoulder range of motion were enrolled in the indoor/outdoor facility of endocrine surgery at the same tertiary center. They were divided into two groups on the basis of a computer-generated randomized table. The study duration was 12 months. Informed consent was taken after explaining the procedure and its complications. Ethical clearance was taken from Institutional Research Committee 919/Ethics/2021.

All patients with breast cancer surgery who were planned for breast surgery were assessed for preoperative shoulder pathology. As usual care following surgery, women were recommended to start gentle upper limb exercises, either active-assisted or passive. Two weeks post-surgery patients are referred to the PMR department for a rehabilitation program. Patients were counseled, and an active rehabilitation program was started to prevent lymphedema and restricted range of motion; then, they were advised for regular follow-up every 3–4 months. Patients who do not take part in active rehabilitation or who lost regular follow-up landed in shoulder restriction and pain. Those patients who fulfilled the inclusion criteria were enrolled in the study. The study was conducted according to Consolidated Standards of Reporting Trials (CONSORT) guidelines (Fig. 1).

Fig. 1.

CONSORT diagram

The following are the inclusion criteria: (1) age > 18 years and < 65 years, (2) diagnosed with primary breast cancer who underwent surgery (MRM or breast conservative surgery with or without ALND or SLNB), (3) painful and limited shoulder motion leading to difficulty in proper positioning of the upper extremity, (4) patients willing to participate in the study.

The following are the exclusion criteria: (1) history with uncontrolled diabetes mellitus; (2) pre-existing shoulder dysfunction before breast surgery; (3) previous treatment (physical therapy, medical treatment, or injection) for incidental shoulder problem; (4) lymphedema of arm and breast following surgery; (5) patient diagnosed with adhesive capsulitis, impingement syndrome, fracture of humerus, dislocation of shoulder joint, and upper extremity nerve injury; (6) local inflammation at the site of injection; (7) skin disease at the site of injection; (8) any allergy to local anesthetic drugs; (9) patient not willing to participate in the study.

Sample Size

There were a total of 48 patients; each group of 24 patients was included.

Methodology

Patients with pain and restricted shoulder range of motion after 2 weeks of following Ca breast surgery were enrolled and randomized into two groups. Group A received USG-guided SSNB followed by an exercise program whereas Group B received only an exercise program.

Outcome Measures

Before planning for SSNB, patients were assessed to rule out any other shoulder pathology and to measure baseline parameters: shoulder range of motion by goniometer, active range of motion noted in all the planes—flexion, extension, abduction, adduction, internal rotation, external rotation. Assessment of pain by visual analog scale (VAS) was done (endpoints: no pain-unbearable pain).

The Disabilities of Arm, Shoulder, and Hand Questionnaire, which is a valid and reliable instrument in breast cancer survivors, was used to assess disability index of Ca breast survivors. Questions were asked to assess difficulty level, and then, it was graded on 100-point scale, with a higher score indicating a great disability.

Procedure

Equipment—B mode real-time ultrasonography was equipped with linear transducer, 23 gauge 60-mm needle, Inj. triamcinolone 20 mg, and Inj. bupivacaine 0.5% 4 ml.

The patient was made to sit comfortably in a relaxed position with a flexed cervical spine and adducted affected arm. Ultrasound probe 5–13 MHz linear transducer was taken. Keep the transducer parallel to the spine of the scapula moving from medial to lateral, until the suprascapular notch is reached (Fig. 2). The suprascapular nerve was visualized at approximately 4–5 cm depth under the transverse scapular ligament as an ovoid hyper-echoic structure. By in-plane approach, a 23G spinal needle was inserted in the mediolateral direction at an angle of 30–45° to the vertical, until the needle tip pierced the deep fascia of the supraspinatus muscle and transverse scapular ligament; a mixture of 20-mg triamcinolone and 4-ml 0.5% bupivacaine was injected slowly under B mode-guided visualization into the area around the nerve (Fig. 3).

Fig. 2.

In-plane approach for SSNB

Fig. 3.

USG imaging of SSNB. TM, trapezius muscle; SM, supraspinatus muscle; SN, suprascapular nerve

All patients were advised structured home-based exercise program [11–13] (pendulum exercise, wall walking, shoulder roll, ROM exercise of shoulder—active, active-assisted exercise, and passive stretching of shoulder flexion and abductors) at a frequency of two to three times a day for 6 days a week, 15- to 30-s duration of each exercise, and each repeated for ten times for 4 weeks.

Follow-up and Data Analysis

Group A patients who underwent USG-guided SSNB were assessed immediately post-procedure for shoulder ROM and VAS and then again reassessed at the 4th week post-procedure for shoulder ROM, VAS, and Q-DASH score. Group B patients were advised to a structured exercise program, and then, they were assessed at 4th week for shoulder ROM, VAS, and Q-DASH score.

All the relevant data collected were entered in the master chart and analyzed using appropriate statistical procedures and SPSS Statistics Windows software version 24.0. Armonk, NY: IBM Corp. Mean, standard deviation, and quantitative variables were used for the descriptive study. Unpaired t-test was used for all parameters except VAS for which the Man-Whitney test was used.

Results

Forty-eight female patients were included in this study with a mean age of 43.58 ± 9.44. All patients (n = 48) underwent modified radical mastectomy with axillary lymph node dissection and shoulder range of motion. The severity of pain was assessed pre-procedure and immediate post-procedure SSNB, whereas shoulder ROM, pain severity, and DASH score were assessed pre-procedure and at 4th week post-procedure. Pain and shoulder flexion were improved immediately post-procedure (Table 1).

Table 1.

Pre- and immediate post-procedure comparison SSNB (IR internal rotation, ER external rotation, VAS visual analog score)

Variables	Pre-procedure	Immediate post-procedure	p-value
Shoulder flexion (degree)	100.83 ± 30.63	113.17 ± 26.48	< 0.001
Shoulder extension (degree)	44.79 ± 20.30	45.00 ± 12.28	0.533
Shoulder abduction (degree)	97.50 ± 29.38	110.21 ± 23.15	0.162
Shoulder adduction (degree)	47.08 ± 6.90	47.08 ± 6.90	0.804
Shoulder IR (degree)	60.00 ± 12.16	59.38 ± 13.54	0.061
Shoulder ER (degree)	80.00 ± 18.18	83.54 ± 15.36	0.274
VAS	6.75 ± 1.87	4.75 ± 2.01	0.006

There was also statistically significant improvement noted in VAS score, DASH score, and shoulder flexion and abduction at the 4th week post-procedure in Group A (Table 2).

Table 2.

Intergroup comparison at 4th week (IR internal rotation, ER external rotation, VAS visual analog score)

Variables	Group A	Group B	p-value
Shoulder flexion (degree)	151.25 ± 16.50	131.42 ± 24.49	0.002
Shoulder extension (degree)	55.83 ± 7.76	55.83 ± 7.17	1.000
Shoulder abduction (degree)	150.00 ± 16.94	131.33 ± 25.08	0.004
Shoulder adduction (degree)	50.00 ± 0.00	50.00 ± 0.00	0.155
Shoulder IR (degree)	67.92 ± 5.88	69.17 ± 2.82	0.353
Shoulder ER (degree)	93.54 ± 8.6	91.25 ± 11.19	0.450
VAS	1.29 ± 1.16	2.54 ± 1.56	0.003
Quick DASH score (%)	34.54 ± 8.55	44.75 ± 7.62	< 0.001

No serious complication was observed. Patients who were not able to receive radiotherapy all received radiotherapy after getting improvement in shoulder range of motion. The overall QoL was improved in Ca breast survivors.

Discussion

The results show clear-cut benefits from SSNB along with the exercise program in Ca breast survivors who presented with pain and restricted shoulder ROM.

Suprascapular nerve block has been widely used for various shoulder pathologies like frozen shoulder, degenerative shoulder condition, and shoulder post-operative pain-related conditions.

In our study, all patients (n = 48) were female, with a mean age of 45 years. Beyaz et al. in year 2016 did a cross-sectional study of the prevalence of post-mastectomy pain, and they found that the prevalence was around 64% in ages between 45 and 55 years [14]. The possible explanation can be because of the incidence of breast cancer which is found to be higher in the pre-menopausal age group, and there are more invasive and aggressive tumors that require extensive surgical treatment, which in turn leads to more post-op complications with higher chances of post-mastectomy pain.

Fabro et al. in a study on the incidence and risks of post-mastectomy pain syndrome found that the incidence of post-mastectomy pain at 6 months was as high as 52.9% in post-mastectomy women [15]. This is similar to our study in which the prevalence of post-mastectomy pain was reported higher at 6–8 months, resulting in difficulty in upper extremity function, hampering the ADL and negatively affecting the QoL.

The baseline values of shoulder ROM (flexion, extension, abduction, adduction, internal rotation, and external rotation) were similar in both groups. The post-procedure improvement was noted in both groups in all six motions of the shoulder that is flexion, extension, abduction, adduction, external rotation, and internal rotation.

However, in intergroup comparison, Group A (SSNB + exercise program for shoulder mobilization) had more significant improvement in shoulder flexion at 4th week (p = 0.002) and abduction at 4th week (p = 0.004) in comparison to Group B. The mean shoulder flexion pre-procedure in Group A was 100.83 ± 30.63 which increased to 151.25 ± 16.50 at 4th week, whereas in Group B, the pre-procedure mean was 107.92 ± 23.77, and it increased to 131.42 ± 24.49 at 4th week. Significant changes were observed in intragroup shoulder flexion at post-procedure (p < 0.001) and at 4th week (p < 0.001). Similarly, the mean abduction was 97.50 ± 29.38 in Group A which increased to 150.00 ± 16.94 at 4th week. The significant changes were observed at post-procedure (p = 0.002) and at 4th week (p < 0.001) in shoulder abduction.

The most common affected range was shoulder flexion, abduction, and external rotation which limits the functional position of the shoulder joint limiting ADL.

The earliest limitation was found to be within 15 days to 1 month after surgery, and it was reported higher in patients who developed post-op complications like wound infection, dehiscence, revision of surgery, not taking part in an active rehabilitation program, and who receive radiotherapy.

The pathophysiology behind restricted ROM of shoulder post-mastectomy was scar tissue formation, fibrosis, and anterior thoracic and axillary region soft tissue shortening. Further chronic inflammation and broken tissue integrity lead to the development of tension and pain in the shoulder joint capsule [16].

The thickened coracohumeral ligament (CHL) was found to be responsible for limiting the external rotation of the shoulder, and the restriction of internal rotation of the shoulder was believed to be related to posterior capsular tightness [17].

The result of the SSNB group in improving shoulder ROM in other shoulder pathologies was consistent with many studies [3, 18–23]. The possible explanation is that pain relief achieved by nerve blockage might be an important factor for the response to the treatment as patients were able to perform exercise with less difficulty; hence, SSNB can be taken as a valuable adjunction therapy.

In terms of pain reduction, using VAS both groups had significant improvement (p < 0.001). However, in Intergroup comparison, Group A that is when SSNB was followed by an exercise program had a more significant difference in VAS score at 4th week (p = 0.003) post-procedure.

The mean pre-procedure VAS in Group A (SSNB + exercise program) was 6.75 ± 1.87, and it reduced to 4.75 immediately post-procedure, and further, it reduced to 1.29 at 4th week post-procedure with a significant difference (p < 0.001).

The SSNB mixture we used in our study had bupivacaine (local anesthetic agent) in it; hence, the immediate effect could be explained by its effect and the triamcinolone (steroid) which acts by inhibiting the action of enzymes such as phospholipase A which causes pain by neural irritation; it also blocks C fibers which leads to less pain transmission to pain which further adds therapeutic effect in pain (Fig. 4).

Fig. 4.

SSNB primary relieves shoulder pain which breaks vicious cycle and improves ROM of shoulder

Another study by Jones and Chattopadhyay [24] found that the duration of benefit of nerve blockage was longer than the pharmacological effect of the drug and proposed that this effect might be associated with desensitization due to decreased peripheral nociceptive input or decreased central sensitivity in nociceptive neurons localized in the dorsal horn; this could explain the sustained and superior benefits of nerve block in our study, and we can assume that this is why suprascapular nerve block group had maximum and sustained changes in VAS score till the end of the 4th week. The prolonged action of SSNB was explained in many studies in improving pain and shoulder ROM in various shoulder pathologies [25–27].

Since exercise programs for shoulder mobilization have also shown significant improvement in VAS scores without the use of pain medication on a regular basis, hence, they can be used as first-line therapy in rehabilitation program.

Mohammed [28] also supported our study in which he concluded that there was a decrease in pain level as well as an improvement in functional status and overall quality of life with a home-based exercise program in post-mastectomy patients.

In our study, Group A had significant improvement in DASH score post-intervention at 4th week post-procedure (p < 0.001). The mean Quick DASH score was 53.92 ± 16.02 in Group A which decreased to 34.54 ± 8.55 at the 4th week, in comparison to Group B in which the mean was 49.29 ± 10.15 in Group B which decreased to 44.75 ± 7.62 at 4th week. A higher DASH score indicates a higher disability, pain, motion restriction, or fear of activity.

Limitation of Study

A small sample size and no blinding reduce the strength of the study.

Conclusion

This study showed that USG-guided SSNB is a low-cost, effective, safe, and promising treatment in post-mastectomy women for fast recovery of restricted ROM of shoulder and pain and reduces the time spent at the hospital; further, it has economic benefits as patients can return to work sooner without the need for hospitalization or spending much time in physical therapy session at hospitals.

To the best of our knowledge, this was the first study done in India, in which we had used USG-guided SSNB in post-mastectomy patients, which proved to be an effective and economically accepted treatment for low socioeconomic populations also.

We confirm that this work is original and has not been published elsewhere, nor it is currently under consideration for publication elsewhere. We believe this article may help health professionals and medical researchers to better understand the topic and this information may be useful for further studies.

Ethics Approval and Consent to Participate

Informed consent was taken after explaining the procedure and its complications. Ethical clearance was taken from Institutional Research Committee 919/Ethics/2021. RCT registration no.: REF/2021/06/044289.

Declarations

Conflict of Interest

The authors declare no competing interests.