Comparison of the effects of ultrasound- guided needle puncture,radial shock wave therapy,and combined treatments on calcific tendinitis of the shoulder: A single-blind randomized controlled trial

Abstract

BACKGROUND:

Calcific tendinitis of the shoulder is a common disorder resulting in restricted motion and pain.

OBJECTIVE:

This study compared the effects of ultrasound-guided fine-needle puncture (USNP), radial shock wave therapy (RSWT), and the combination of both treatments (COMB) on calcific tendinitis of the shoulder.

METHODS:

We enrolled 62 patients who had unilateral shoulder pain for more than 3 months. The patients were randomly divided into three groups: USNP, RSWT, and COMB. All USNP needle punctures were guided with ultrasound (US), and RSWT was delivered at 2 Hz (2000 shock waves; 0.26 mJ/mm ${}^{2}$ ) once a week for 3 weeks. The COMB group received three weekly rounds of RSWT after a single US-guided needle puncture. The primary outcome was the pain visual analog scale (VAS), and secondary outcomes were the Constant scores, 36-Item Short-Form Health Survey, and range of motion.

RESULTS:

A within-group comparison at 3 months revealed significant improvements in the pain VAS ( $p<$ 0.05, during activity) and Constant ( $p<$ 0.05) scores, but between-group comparisons revealed no statistically significant differences in the pain VAS ( $p>$ 0.05) or Constant ( $p=$ 0.089) scores. Only improvement differences in role-emotional (SF-36; $p=$ 0.01) and active external rotation ( $p=$ 0.035) were determined over time, which favored the USNP and COMB groups.

CONCLUSIONS:

Although no significant differences were observed among the groups in the treatment of calcific tendinitis of the shoulder, more satisfactory outcomes were noted in the USNP and COMB groups than in the RSWT group. Larger samples, longer follow-up times, and other treatment protocols are suggested for future studies.

Keywords

Shoulder pain tendinitis extracorporeal shockwave therapy ultrasonography

1. Introduction

Calcific tendinitis of the shoulder is a common disorder associated with inflammation around calcium hydroxyapatite crystal deposits [1]. This disorder is commonly observed in individuals between 30 and 50 years of age and is painful in 50% of patients [2]. It may also result in a considerably restricted range of motion (ROM) of the affected shoulder. Calcific tendinitis progresses through three distinct stages, namely the precalcific (metaplasia of matrix), calcific (calcification of matrix and resorption of calcific deposits), and postcalcific (reconstitution of matrix) stages.

The classification system proposed by Gartner based on radiographic findings using plain films of the shoulder consists of three types. In type I, deposits are sharply outlined and densely structured, and in type II, the deposits are similar to those in type I or have a cloudy and dense outline and are transparent; in type III, the deposits have a cloudy outline with a transparent structure [3]. Type III plaques have a tendency to resorb. Because of the progression of musculoskeletal ultrasound (US) technology, Chiou proposed another classification system of calcific tendinitis based on US findings as follows: arc-shaped, fragmented or punctate, nodular, or cystic [4]. Plaques that appear fragmented, nodular, or cystic in US images are considered to be in the resorptive phase.

In a recent systematic review [5], needling proved beneficial for patients with subacute or chronic symptoms; however, few studies have compared the effects of needling on the various stages of calcific tendinitis. The failure rate of nonsurgical therapy did not differ significantly between Gartner’s type I and II calcifications in one study [6], whereas in another study, extracorporeal shockwave therapy (ESWT) promoted the breakdown of calcific deposits in both type I and type II calcifications, with respective elimination rates of 30.8% and 61.0% [7]. Consequently, patients with these two types of calcific tendinitis were suitable for the receipt of US-guided needling or ESWT.

Patients with calcific tendinitis are typically treated conservatively, with reported success rates of 30% to 85% [8]. Arthroscopic and open procedures may be advised to curette the calcium deposits in instances in which the pain is chronic or intermittent after several months of conservative treatment; additional subacromial decompression can be performed if necessary [9, 10]. Alternatively, minimally invasive ESWT has been suggested to be an effective treatment option for calcific tendinopathy of the shoulder before surgery [11, 12]. Although ESWT has been studied extensively in relation to musculoskeletal injuries in recent decades, the precise mechanism involved in promoting tissue repair remains elusive [13]. Loew et al. reported that ESWT can induce fragmentation and cavitation of calcific deposits and promote phagocytosis; additionally, it can exert an analgesic effect by influencing pain receptors and neurotransmitters [14].

In recent years, radial shock wave therapy (RSWT) has gained popularity. A radial shock wave is a low-to-medium-energy shock wave that is pneumatically generated through the acceleration of a projectile inside the handpiece of the treatment device and then transmitted radially from the tip of the applicator to the target zone. Radial shock waves exhibit lower pressure and considerably longer rise times than do extracorporeal shock waves. In RSWT, the focal point is not concentrated on the target zone, as in ESWT, but rather on the tip of the applicator [15].

Another conservative method for treating calcific tendinopathy is US-guided fine-needle puncturing (USNP) of the calcific plaque [4, 16]. This method is easy to operate, cheap, safe, and highly successful. Although percutaneous needle aspiration with a large ( $\geqslant$ 18-gauge) needle alleviates symptoms in up to 60% of patients and resolves deposits in 40% to 74% of patients [17, 18], a large needle could cause an injury to the tendon.

A study reported promising clinical and radiological outcomes through a combination of shock wave therapy and US-guided needling [7]. Repeated needle punctures could break down calcific deposits, and RSWT induced fragmentation and cavitation, which made calcium deposits more absorbable [7]. However, few scientific studies on the combined effects of RSWT and USNP have been published. The present study compared the efficacy of USNP, RSWT, and the combination of both to treat calcific tendinitis of the shoulder.

2. Materials and methods

2.1 Design

This prospective randomized controlled trial (RCT) was approved by the institutional review board of Shin Kong Wu Ho-Su Memorial Hospital (20120801R) and registered at ClinicalTrials.gov (NCT02677103). An assignment scheme was generated from a table of random numbers. Written informed consent was obtained from all patients, who were subsequently randomly divided into three treatment groups: USNP, RSWT, and RSWT plus USNP (COMB).

2.2 Participants

Between January 2013 and December 2014, 75 patients with calcific tendinitis of the shoulder were recruited from the outpatient clinic at the Department of Physical Medicine and Rehabilitation of the authors’ institution. The inclusion criteria of this study were as follows: 1) between 20 and 75 years of age; 2) at least a 3-month history of unilateral shoulder discomfort; and 3) radiological evidence of both type I and type II calcification – as defined by Gartner – or US-based evidence of arc-shaped calcification – as defined by Chiou [4]. The exclusion criteria were pregnancy, clotting disorders, anticoagulant or antiplatelet treatment, cardiac pacemaker, chronic inflammatory joint disease, infection or tumor of the shoulder, adhesive capsulitis, hyperalgesia of the shoulder due to resorption of a calcific deposit, Garner’s type III calcification, or Chiou’s nodular or cystic calcification [4].

2.3 Interventions

All treatments were administered at the Department of Physical Medicine and Rehabilitation by a physiatrist who was familiar with both types of therapy. RSWT was delivered at 2 Hz (2000 shock waves; energy level, 0.26 mJ/mm ${}^{2}$ ) once a week for 3 weeks. Instead of nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen was prescribed as a rescue medication to avoid negative effects on tissue healing. The amount dispensed was recorded at the end of the study.

All needle punctures for the USNP and COMB groups were guided by US and performed once. A 3.8-cm-long 22-gauge needle attached to a 5-mL syringe was used for puncturing. The puncture site was sterilized with iodine, and the transducer was covered with a sterilized plastic bag. After injecting 3 cc of lidocaine (1%) into the subcutaneous tissue, muscle layer, and subdeltoid bursa, multiple punctures (10–20, depending on plaque size) were performed without aspiration or barbotage. The needle tract was monitored with US to ensure that the needle penetrated through the calcific plaque but not the rotator cuff [4]. The patients in the COMB group received three weekly rounds of RSWT after USNP.

2.4 Assessment

All assessments were performed by a masked assessor who was a trained study assistant. The patients were instructed not to reveal any treatment details to the assessor. Except for shoulder radiographs, all assessments and standard sonograms were conducted at baseline and 1.5 and 3 months after completion of the treatment.

Demographic data, namely age, sex, body weight, height, history of diabetes mellitus, and exercise habits, were recorded at baseline. Additionally, information regarding complaint duration (months), previous treatments (injections, physical therapy), and current pain medications was obtained. Occurrence of concomitant diseases and use of medications were also recorded.

Initial radiographs of the shoulder comprised anteroposterior films in neutral, internal, and external rotations. Deposits in the supraspinatus were readily visible on the films in the neutral position, whereas deposits in the infraspinatus and teres minor were most clearly observable during the internal rotation. Calcifications in the subscapularis were most clearly observable in the external rotation of the shoulder.

2.5 Outcome measures

The primary outcome measure was the visual analog scale (VAS) to assess pain. Pain was measured using three VASs (horizontal lines measuring 100 mm in length, with 0 on the left indicating no pain and 100 on the right indicating severe pain) pertaining to shoulder pain at rest, during movement, and during sleep. The pain VAS is a reliable and sensitive tool for measuring pain, with a test-retest reliability of $>$ 0.90. The responsiveness of the pain VAS in patients treated for various shoulder disorders reportedly varied from moderate to good [19].

Table 1
Demographic and clinical characteristics of the subjects

Characteristic	USNP group ( $n=$ 21)	RSWT group ( $n=$ 20)	COMB group ( $n=$ 20)	USNP vs. RSWT	USNP vs. COMB	RSWT vs. COMB
				$p$	$p$	$p$
Age (y)	58.2 $\pm$ 7.9	57.6 $\pm$ 9.4	56.6 $\pm$ 6.8	0.93	0.57	0.68
Male/female	8/13	8/12	7/13	0.90	0. 84	0.74
Weight (kg)	60.9 $\pm$ 11.2	60.3 $\pm$ 10.7	59.3 $\pm$ 9.7	0.77	0.64	0.82
Height (cm)	161.0 $\pm$ 8.1	160.7 $\pm$ 8.5	159.8 $\pm$ 7.4	0.80	0.69	0.74
Disease duration (months)	13.8 $\pm$ 21.7	21.3 $\pm$ 31.5	24.3 $\pm$ 30.1	0.33	0.06	0.37
History of diabetes mellitus	4	2	2	0.49	0.41	0.98
Exercise habits	10	10	7	0.88	0.41	0.34
Previous treatment
Injection	17	16	16	0.94	0.94	1
PT	6	6	9	0.92	0.28	0.33
NSAID	10	10	11	0.88	0.64	0.75

Abbreviations: USNP $=$ ultrasound-guided needle puncture; RSWT $=$ radial shock wave therapy; COMB $=$ combination of both treatments; PT $=$ physical therapy; NSAID $=$ non-steroidal anti-inflammatory drug. Note: Values are expressed as means $\pm$ SD or numbers. Group differences were analyzed using either a chi-squared test or Mann-Whitney U test. $P$ value $<$ 0.05, significant difference.

The secondary outcome measures in this study were the Constant scores, the 36-Item Short-Form Health Survey (SF-36) for general health status, and the ROM of the afflicted shoulder. The Constant score is a 100-point scoring system comprising 15 points for pain, 20 points for activities of daily living, 40 points for shoulder motion, and 25 points for muscle power of the affected arm [20]. The psychometric properties of the SF-36 have been established in Chinese. The SF-36 is a generic measure of quality of life comprising eight subscales: physical functioning, social functioning, role-physical (role limitations due to physical limitations), role-emotional (role limitations due to emotional problems), mental health, vitality, body pain, and general health. Each subscale generates a score between 0 and 100, with a higher score indicating superior health. Two summary scales for physical and mental health can be computed based on these eight items [21]. Following the guidelines of the American Academy of Orthopaedic Surgeons [22], active and passive ROMs were measured using a conventional goniometer; the measurements included abduction in the frontal plane, forward flexion, internal rotation, and external rotation with the arm at 0 degrees of abduction. Goniometric measurements of the shoulder maintained high reliability when performed by a physical therapist [23].

2.6 Ultrasonographic evaluation

The calcific deposit size was measured with ultrasonography at baseline and during follow-ups at 1.5 and 3 months. Resorption of the calcific deposit was graded as none, partial, or complete by a physiatrist who was blinded to the treatment modes allocated to the patients.

2.7 Statistics

The sample size was calculated by assuming the presence of differences in the primary outcome (pain VAS during activity at 3-month follow-up) among the three groups before conducting the study. Based on power calculations performed using G*Power 3.1.9.2, a total of 63 patients were required to achieve a power of 80% at a type I error level of 0.05 and effect size of 0.5.

Means and standard deviations were reported for continuous measurements. A chi-squared test and the Mann-Whitney U test were used for baseline comparisons and to measure changes in the pain VAS values during activity. No violation of normal distribution from the outcome measurements data was detected using the Kolmogorov-Smirnov test of normality. Analysis of variance for repeated measures was used to analyze the effects of time and the interaction between time and groups. Significance was set at $p<$ 0.05.

Figure 1.

Flowchart of enrolment and randomisation of the patients in this study. Abbreviations: USNP, ultrasound-guided needle puncture; RSWT, radial shock wave therapy; COMB, combination of both treatments.

Figure 2.

A case in COMB group with ultrasonography during needling of the calcific plaques in the right supraspinatus tendon (A), radial shock wave therapy (B), pre-treatment X-ray (C) and post 3-month X-ray (D). (Abbreviations: D, deltoid; SS, supraspinatus; med, medial; lat, lateral; CP, calcific plaques; $\blacktriangle$ , needle).

3. Results

3.1 Baseline characteristics

A total of 75 patients with calcific tendinitis of the shoulder were examined in this study. Thirteen patients were excluded because of adhesive capsulitis (10), anticoagulant or antiplatelet medication (2), or pregnancy (1). One participant in the RSWT group was lost to follow-up at the 1.5-month evaluation. A total of 21, 20, and 20 patients were included in the USNP, RSWT, and COMB groups, respectively (Fig. 1). No significant differences in age, sex, body weight, height, disease duration, exercise habits, history of diabetes mellitus, previous treatment (including injection and physical therapy), or current nonsteroidal anti-inflammatory drug medication use were observed among the three groups (Table 1). A patient in the COMB group is presented in Fig. 2.

3.2 Primary outcome measures

Within-group comparisons at the 1.5- and 3-month follow-ups revealed significant improvements in the pain VAS during sleep, rest, and activity (Table 2). No statistically significant differences were observed among the groups during the 1.5- and 3-month follow-up periods (Table 2). Furthermore, we analyzed the number of patients whose changes in the pain VAS (during activity) score reached the minimal clinically important difference (MCID) in each group. The MCID of the pain VAS was 1.4 cm, according to a previous study [24]. A significant difference was observed between the USNP and RSWT groups at the 1.5-month follow-up ( $p=$ 0.037), which favored the USNP group. When compared with the RSWT groups, both USNP ( $p=$ 0.031) and COMB ( $p=$ 0.013) groups had significantly more participants reaching the MCID at the 3-month follow-up (Table 3).

Table 2
Scores from questionnaires for the USNP, RSWT, and COMB groups at three evaluation times

Scores on questionnaires		Group	Evaluation time			Main effects		Interaction
			Pre-treatment	Post 1.5-month	Post 3-month	$p$ time ${}^{*}$	$p$ group ${}^{*}$	Group*time
VAS	Sleep	USNP	6.76 $\pm$ 3.40	4.14 $\pm$ 2.89	2.71 $\pm$ 2.19	$<$ 0.001 ${}^{*}$	0.477	0.871
		RSWT	5.75 $\pm$ 2.77	3.90 $\pm$ 3.51	2.65 $\pm$ 3.12
		COMB	5.60 $\pm$ 3.56	3.60 $\pm$ 2.93	1.75 $\pm$ 2.61
	Rest	USNP	4.29 $\pm$ 3.95	2.19 $\pm$ 2.71	0.95 $\pm$ 1.40	$<$ 0.001 ${}^{*}$	0.336	0.213
		RSWT	2.90 $\pm$ 2.95	0.90 $\pm$ 1.52	1.55 $\pm$ 2.31
		COMB	2.85 $\pm$ 3.62	1.05 $\pm$ 1.99	0.80 $\pm$ 2.31
	Activity	USNP	7.38 $\pm$ 2.44	4.10 $\pm$ 2.12	3.00 $\pm$ 2.53	$<$ 0.001 ${}^{*}$	0.561	0.144
		RSWT	5.50 $\pm$ 2.33	4.05 $\pm$ 2.31	3.15 $\pm$ 3.00
		COMB	6.60 $\pm$ 2.66	3.75 $\pm$ 2.29	2.70 $\pm$ 2.52
Constant score		USNP	40.95 $\pm$ 11.94	52.52 $\pm$ 14.62	62.14 $\pm$ 16.54	$<$ 0.001 ${}^{*}$	0.449	0.089
		RSWT	47.25 $\pm$ 14.73	57.45 $\pm$ 12.95	64.15 $\pm$ 16.91
		COMB	41.10 $\pm$ 10.24	56.65 $\pm$ 11.07	69.10 $\pm$ 13.54
SF-36	Physical functioning	USNP	70.95 $\pm$ 13.29	76.90 $\pm$ 15.85	82.38 $\pm$ 14.80	$<$ 0.001 ${}^{*}$	0.149	0.080
		RSWT	68.00 $\pm$ 17.50	66.25 $\pm$ 15.38	70.25 $\pm$ 16.74
		COMB	61.25 $\pm$ 20.58	70.50 $\pm$ 19.66	75.75 $\pm$ 22.38
	Role-physical	USNP	32.14 $\pm$ 38.03	50.00 $\pm$ 44.72	61.90 $\pm$ 48.49	$<$ 0.001 ${}^{*}$	0.576	0.097
		RSWT	46.25 $\pm$ 45.36	61.25 $\pm$ 44.04	52.95 $\pm$ 43.14
		COMB	17.50 $\pm$ 29.36	46.25 $\pm$ 42.36	61.25 $\pm$ 50.96
	Bodily pain	USNP	50.19 $\pm$ 21.82	61.62 $\pm$ 18.71	70.52 $\pm$ 16.55	$<$ 0.001 ${}^{*}$	0.353	0.808
		RSWT	45.95 $\pm$ 16.10	54.80 $\pm$ 14.54	62.15 $\pm$ 16.28
		COMB	45.50 $\pm$ 16.89	58.25 $\pm$ 15.12	68.15 $\pm$ 16.70
	General health	USNP	56.57 $\pm$ 23.29	53.76 $\pm$ 22.45	58.10 $\pm$ 20.10	0.370	0.248	0.180
		RSWT	57.55 $\pm$ 15.38	56.30 $\pm$ 13.86	55.15 $\pm$ 15.54
		COMB	60.55 $\pm$ 20.58	64.65 $\pm$ 21.31	68.05 $\pm$ 20.18
	Vitality	USNP	58.81 $\pm$ 15.64	55.48 $\pm$ 13.41	60.24 $\pm$ 16.69	0.117	0.726	0.160
		RSWT	54.50 $\pm$ 17.98	56.25 $\pm$ 17.46	58.38 $\pm$ 17.10
		COMB	49.50 $\pm$ 22.41	57.50 $\pm$ 19.90	55.50 $\pm$ 19.80
	Social functioning	USNP	73.81 $\pm$ 19.33	75.00 $\pm$ 22.36	79.76 $\pm$ 20.72	0.898	0.916	0.306
		RSWT	78.13 $\pm$ 16.66	77.50 $\pm$ 17.01	71.25 $\pm$ 19.49
		COMB	75.63 $\pm$ 19.65	78.75 $\pm$ 16.27	78.13 $\pm$ 17.15
	Role-emotional	USNP	65.08 $\pm$ 40.11	69.84 $\pm$ 40.70	84.13 $\pm$ 30.95	0.005 ${}^{*}$	0.589	0.010 ${}^{*}$
		RSWT	68.33 $\pm$ 43.90	75.00 $\pm$ 37.27	61.93 $\pm$ 43.68
		COMB	40.00 $\pm$ 42.71	68.33 $\pm$ 38.20	80.00 $\pm$ 42.44
	Mental health	USNP	64.76 $\pm$ 14.78	59.62 $\pm$ 17.48	63.05 $\pm$ 18.02	0.445	0.462	0.386
		RSWT	66.20 $\pm$ 17.91	65.00 $\pm$ 12.44	74.80 $\pm$ 45.99
		COMB	62.60 $\pm$ 14.35	67.20 $\pm$ 13.46	65.00 $\pm$ 15.24

Abbreviations: USNP $=$ ultrasound-guided needle puncture; RSWT $=$ radial shock wave therapy; COMB $=$ combination of both treatments; VAS $=$ visual analog scale; SF-36 $=$ 36-item Short-Form Health Survey. Note: Values are expressed as means $\pm$ SD. Treatment time effects were analyzed using Friedman’s test for each group respectively. ${}^{*}P$ value $<$ 0.05, significant difference.

Table 3

Numbers of the patients whose changes of the values in the pain VAS during activity reached the MCID

	USNP group ( $n=$ 21)	RSWT group ( $n=$ 20)	COMB group ( $n=$ 20)	USNP vs. RSWT	USNP vs. COMB	RSWT vs. COMB
				$p$	$p$	$p$
$\geqslant$ MCID (1.4) at 1.5-month	17	10	15	0.037 ${}^{*}$	0.645	0.102
$\geqslant$ MCID (1.4) at 3-month	18	11	17	0.031 ${}^{*}$	0.675	0.013 ${}^{*}$

Abbreviation: MCID $=$ minimal clinical important difference. ${}^{*}P$ value $<$ 0.05, significant difference.

3.3 Secondary outcome measures

Within-group comparisons at 1.5- and 3-month follow-ups revealed significant Constant score improvements, but no other significant difference was observed among the groups during those periods (Table 2). Between-group comparisons conducted using the SF-36 revealed nonsignificant improvements in the physical functioning, role-physical, bodily pain, and role-emotional subscales among three groups over time. Only the role-emotional subscale revealed a significant time-group interaction ( $p=$ 0.01). The improvement change in RSWT decreased over time compared with the other groups. Although nonsignificant, a similar trend was observed in the physical functioning ( $p=$ 0.08) and role-physical subscales ( $p=$ 0.097) of the SF-36 (Table 4 and Fig. 3). In the ROM analysis, all groups exhibited improvements in active and passive flexion, abduction, and external rotation, except for active internal rotation over time, but the result was not significant between groups. Only active external rotation exhibited a significant difference in the improvement change over time among the three groups (Table 4 and Fig. 3), and no side effects were observed in the patients.

Table 4
Range of motion for the USNP, RSWT, and COMB groups at three evaluation times

Scores on questionnaires		Group	Evaluation time						Main effects		Interaction
			Pre-treatment		Post 1.5-month		Post 3-month		$p$ time ${}^{*}$	$p$ group ${}^{*}$	Group*time
Active ROM	Flexion	USNP	156.05	$\pm$ 12.64	162.24	$\pm$ 17.56	167.14	$\pm$ 14	$<$ 0.001 ${}^{*}$	0.498	0.34
		RSWT	160.40	$\pm$ 17.90	165.55	$\pm$ 10.21	167.30	$\pm$ 10.82
		COMB	151.10	$\pm$ 17.34	162.55	$\pm$ 13.45	166.60	$\pm$ 10.43
	Abd	USNP	130.19	$\pm$ 39.18	138.29	$\pm$ 37.64	149.38	$\pm$ 25.08	$<$ 0.001 ${}^{*}$	0140	0.22
		RSWT	151.55	$\pm$ 25.54	152.75	$\pm$ 24.15	159.20	$\pm$ 22.44
		COMB	132.25	$\pm$ 27.33	145.85	$\pm$ 19.04	154.50	$\pm$ 19.37
	ER	USNP	56.86	$\pm$ 17.23	60.29	$\pm$ 16.81	63.90	$\pm$ 11.03	$<$ 0.001 ${}^{*}$	0.317	0.035 ${}^{*}$
		RSWT	64.65	$\pm$ 7.53	65.80	$\pm$ 9.69	64.20	$\pm$ 9.56
		COMB	61.90	$\pm$ 16.15	66.10	$\pm$ 11.65	68.55	$\pm$ 10.91
	IR	USNP	60.86	$\pm$ 8.91	63.19	$\pm$ 8.22	64.48	$\pm$ 7.04	0.858	0.378	0.558
		RSWT	67.05	$\pm$ 25.22	65.30	$\pm$ 5.08	64.85	$\pm$ 6.92
		COMB	61.65	$\pm$ 6.47	62.50	$\pm$ 6.02	62.80	$\pm$ 9.10
Passive ROM	Flexion	USNP	159.10	$\pm$ 12.59	165.05	$\pm$ 17.11	169.95	$\pm$ 13.60	$<$ 0.001 ${}^{*}$	0.375	0.558
		RSWT	162.35	$\pm$ 18.19	167.65	$\pm$ 10.04	169.80	$\pm$ 10.51
		COMB	153.30	$\pm$ 17.95	163.30	$\pm$ 14.76	167.90	$\pm$ 10.30
	Abd	USNP	132.19	$\pm$ 39.17	140.57	$\pm$ 37.80	153.76	$\pm$ 23.19	$<$ 0.001 ${}^{*}$	0.136	0.101
		RSWT	155.40	$\pm$ 24.49	154.75	$\pm$ 23.16	161.40	$\pm$ 21.87
		COMB	133.20	$\pm$ 35.03	149.20	$\pm$ 18.22	157.05	$\pm$ 18.62
	ER	USNP	58.86	$\pm$ 17.37	62.90	$\pm$ 15.43	66.86	$\pm$ 10.06	0.002 ${}^{*}$	0.344	0.133
		RSWT	65.95	$\pm$ 7.25	67.20	$\pm$ 9.04	66.50	$\pm$ 10.25
		COMB	65.70	$\pm$ 13.41	67.60	$\pm$ 11.68	69.65	$\pm$ 10.28
	IR	USNP	62.57	$\pm$ 8.78	66.14	$\pm$ 7.79	67.05	$\pm$ 6.10	$<$ 0.001 ${}^{*}$	0.578	0.843
		RSWT	63.80	$\pm$ 6.14	67.05	$\pm$ 5.26	67.15	$\pm$ 7.86
		COMB	62.05	$\pm$ 10.39	64.05	$\pm$ 6.09	65.55	$\pm$ 5.68

Abbreviations: ROM $=$ range of motion; USNP $=$ ultrasound-guided needle puncture; RSWT $=$ radial shock wave therapy; COMB $=$ combination of both treatments. Note: Values are expressed as means $\pm$ SD. Treatment time effects were analyzed using Friedman’s test for each group respectively. ${}^{*}P$ value $<$ 0.05, significant difference.

Figure 3.

Average changes in physical-functioning (SF-36), role-physical (SF-36), role-emotional and active external rotation at pre-treatment, post 1.5-month and 3-month. Abbreviations: SE-36, 36-Item Short-Form Health Survey.

3.4 Ultrasonographic findings

Calcification was observed at the long head of the biceps (1 patient), supraspinatus (53 patients), subscapularis (11 patients), and infraspinatus (10 patients) tendons. Eleven patients exhibited calcification in more than one tendon. The average calcification size was 0.99 $\pm$ 0.41 cm at baseline. After 3 months of follow-up, the calcifications had disappeared completely in 9.5%, 10%, and 10% of the patients and partially in 90.5%, 80%, and 85% of the patients in the USNP, RSWT, and COMB groups, respectively. No significant differences were noted among the three groups.

4. Discussion

A comparison between the groups indicated no significant differences in pain and shoulder functioning. Nonetheless, the USNP and COMB groups demonstrated a superior trend in pain VAS scores during activity (Table 3), some SF-36 subscales, and ROM, compared with the RSWT group during follow-up (Fig. 3). The benefits of USNP and the combined treatments could be attributed to several factors. First, USNP utilizes radiation-free image guidance to visualize calcification, thereby facilitating repeated punctures more precisely. Second, the needle’s mechanical breakdown of the calcific deposits could aid the reabsorption of the calcium particles into blood. Third, subsequent shock wave therapy could lead to further disintegration. Additionally, the temporary analgesic effects produced by lidocaine in the subcutaneous tissues and bursa in the USNP and COMB groups might have influenced the outcomes. A 2014 systematic review presented moderate evidence that US-guided needling plus ESWT was more effective than ESWT alone, but evidence regarding a comparison among ESWT, USNP, and combined treatments is limited [25]. A further meta-analysis demonstrated that USNP combined with subacromial corticosteroid injections was more effective than other treatments in terms of the Constant scores, VAS scores, and size of the calcium deposits [26]. To the best of our knowledge, this was the first study comparing RSWT, USNP, and combined treatments for calcific tendinitis of the shoulder.

Krasny et al. compared USNP followed by high-energy shockwave therapy and shockwave therapy alone in an RCT. In that study, shockwave therapy was applied only once for each patient in a fixed amount of 2500 impulses with an energy flux density of 0.36 mJ/mm ${}^{2}$ . The results revealed no statistically significant differences between the two groups when comparing the improvement of the stepwise Constant scores, but the percentage of normal and pain-free ROM of the shoulder was higher in the group receiving combined therapy [7]. In the present study, we used RSWT with 2000 impulses with an energy flux density of 0.26 mJ/mm ${}^{2}$ once a week for 3 weeks to enhance the effect of the shock wave therapy. However, the benefit of the combined treatment was nonsignificant for most of the outcome measurements for several possible reasons, including the type and settings of the shock wave therapy, number of sessions of shock waves, and differences in treatment durations and follow-up periods.

On the basis of two studies that compared US-guided needling and shock wave therapy alone, US-guided needling appeared superior to ESWT in restoring functions, providing short-term relief from pain, and accelerating the resorption of calcification [27, 28]; however, corticosteroid injections were provided to the patients in the US-guided needling group in both studies, a practice that differed from the current study. Corticosteroids can suppress inflammation and have possible analgesic effects on neuropeptides, but may cause adverse reactions such as bursa infections, tendon ruptures, and postinjection pain [29]. To eliminate possible adverse events from corticosteroids and focus on the mechanical effect of needling, we only injected lidocaine during US-guided needling.

A statistically significant difference was found in the role-emotional subscale of SF-36 and the active external rotation with time. At baseline, the scores of the role-emotional subscale were significantly lower in the COMB group than in the other groups. Because the patients were not blinded in this study, they may have had expectation bias that influenced their emotions. Although the degree change in patients’ active external rotation was statistically higher in the USNP and COMB groups, the MCID of 13 degrees was not reached [30]. Overall, a superior trend was observed in some SF-36 subscales for the USNP and COMB groups (Fig. 3), but no significant difference was noted in the ROM of the shoulder among the groups.

Because of the widespread use of high-resolution ultrasonography, several studies have examined multiple techniques to approach calcification. Among them, needle barbotage, a procedure involving repeated punctures combined with aspiration, was used most often. This technique can be performed using single or double needles, both of which present favorable outcomes [5]. However, frequent pain and discomfort were reported during the procedure because of the repeated puncturing of the skin’s surface [13]. Additionally, posttreatment complications of US-guided needling, such as frozen shoulder and subacromial bursitis, have been reported, albeit rarely [13]. Zhu et al. compared the effects of USNP with and without aspiration and revealed no significant differences in outcomes [16]. Therefore, we used single needle puncturing without aspiration in the current study to minimize discomfort and the risk of tendon injury.

RSWT has a lower peak pressure and longer rise time than focused shock wave therapy, which could reduce pain during treatment and lower the complication rate [15]. Hence, medium-energy RSWT was applied in the present study [31]. Cacchio et al. reported a high reabsorption rate of calcification after the administration of RSWT in a randomized study; nonetheless, to the best of our knowledge, no study has compared the effectiveness of radial and focused ESWT for treating calcific tendinitis [15].

One limitation of this study was the absence of a control group because of ethical concerns and difficulties in the experimental design. The natural course of calcification reabsorption could not be observed in our study. Therefore, we focused on the effects between combined therapy and a single treatment. Second, the follow-up period was only 3 months; a long-term follow-up may yield a higher resorption rate of calcium deposits [16, 32]. Third, neither the doctors nor patients were blinded because of technical limitations.

5. Conclusion

In our study, the application of USNP, RSWT, or a combined therapy regimen in the treatment of calcific tendinitis of the shoulder revealed lower pain intensity and improved function during a 3-month follow-up period than at baseline. Although no statistical significance was observed in pain, function, quality of life, or ROM among the three groups, a trend was noted in favor of the USNP and COMB groups. Additional studies with a placebo group, other treatment protocols, larger samples, and longer follow-up durations are required to validate the efficacy of these treatments.

Footnotes

Conflict of interest

The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding

This study was financially supported by Shin Kong Wu Ho-Su Memorial Hospital of Taiwan (SKH-8302-102-DR-33).

References

Pederson

Key

. Pathology of calcareous tendinitis and subdeltoid bursitis. AMA Arch Surg. 1951 Jan; 62(1): 50-63.

Bosworth

. Calcium deposits of the shoulder and subacromial bursitis: Survey of 12122 shoulders. JAMA. 1941 May; 116(22): 2477-82.

Gartner

. Tendinosis calcarea-results of treatment with needling. Z Orthop Ihre Grenzgeb. 1993 Sep-Oct; 131(5): 461-9. German.

Chiou

Chou

Hsu

Huang

Chang

. The role of high-resolution ultrasonography in management of calcific tendnonitis of the rotator cuff. Ultrasound Med Biol. 2001 Jun; 27(6): 735-43.

Gatt

Charalambous

. Ultrasound-guided barbotage for calcific tendonitis of the shoulder: A systematic review including 908 patients. Arthroscopy. 2014 Sep; 30(9): 1166-72.

Ogon

Suedkamp

Jaeger

Izadpanah

Koestler

Maier

. Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder. Arthritis Rheum. 2009 Oct; 60(10): 2978-84.

Krasny

Enenkel

Aigner

Wlk

Landsiedl

. Ultrasound-guided needling combined with shock-wave therapy for the treatment of calcifying tendonitis of the shoulder. J Bone Joint Surg Br. 2005 Apr; 87(4): 501-7.

Mouzopoulos

Stamatakos

Mouzopoulos

Tzurbakis

. Extracorporeal shock wave treatment for shoulder calcific tendonitis: A systematic review. Skeletal Radiol. 2007 Sep; 36(9): 803-11.

Rochwerger

Franceschi

Viton

Roux

Matei

. Surgical management of calcific tendinitis of the shoulder: An analysis of 26 cases. Clin Rheumatol. 1999; 18(4): 313-6.

10.

Jerosch

Strauss

Schmiel

. Arthroscopic treatment of calcific tendinitis of the shoulder. J Shoulder Elbow Surg. 1998 Jan-Feb; 7(1): 30-7.

11.

Gerdesmeyer

Wagenpfeil

Haake

Meier

Loew

Wörtler

Lampe

Seil

Handle

Gassel

Rompe

. Extracorporeal shock wave therapy for the treatment of chronic calcifying tendonitis of the rotator cuff: Randomized controlled trial. JAMA. 2003 Nov 19; 290(19): 2573-80.

12.

Oliva

GiaiVia

Maffulli

. Calcific tendinopathy of the rotator cuff tendons. Sports Med Arthrosc Rev. 2011 Sep; 19(3): 237-43.

13.

Louwerens

Veltman

van Noort

van den Bekerom

. The effectiveness of high-energy extracorporeal shockwave therapy versus ultrasound-guided needling versus arthroscopic surgery in the management of chronic calcific rotator cuff tendinopathy: A systematic review. Arthroscopy. 2016 Jan; 32(1): 165-75.

14.

Loew

Jurgowski

Mau

Thomsen

. Treatment of calcifying tendinitis of rotator cuff by extracorporeal shock waves: A preliminary report. J Shoulder Elbow Surg. 1995 Mar-Apr; 4(2): 101-6.

15.

Cacchio

Paoloni

Barile

Don

de Paulis

Calvisi

Ranavolo

Frascarelli

Santilli

Spacca

. Effectiveness of radial shock-wave therapy for calcific tendinitis of the shoulder: Single-blind randomized clinical study. Phys Ther. 2006 May; 86(5): 672-82.

16.

Zhu

Jiang

Xing

. Evaluating the long-term effects of ultrasound-guided needle puncture without aspiration on calcifying supraspinatus tendinopathy. Adv Ther. 2008 Nov; 25(11): 1229-34.

17.

Farin

Rasanen

Jarcoma

Jarju

. Rotator cuff calcifications: Treatment with ultrasound-guided percutaneous needle aspiration and lavage. Skeletal Radiol. 1996 Aug; 25(6): 551-4.

18.

Gärtner

Heyer

. Tendinosis calcarea der Schulter [Calcific tendinitis of the shoulder]. Orthopade. 1995 Jun; 24(3): 284-302. German.

19.

Boonstra

Schiphorst Preuper

Reneman

Posthumus

Stewart

. Reliability and validity of the visual analogue scale for disability in patients with chronic musculoskeletal pain. Int J Rehabil Res. 2008 Jun; 31(2): 165-9.

20.

Constant

Murley

. A clinical method of functional assessment of the shoulder. Clin Orthop Relat Res. 1987 Jan; (214): 160-4.

21.

Ware

Jr Sherbourne

. The MOS 36-item short-form health survey (SF-36), I: conceptual framework and item selection. Med Care. 1992 Jun; 30(6): 473-83.

22.

Norkin

White

. Measurement of joint motion: A guide to goniometry. Philadelphia, F.A. Davis, 2009. (ISBN No.978-0803620667).

23.

Riddle

. Goniometric reliability in a clinical setting: Shoulder measurements. Phys Ther. 1987 May; 67(5): 668-73.

24.

Tashjian

Deloach

Porucznik

Powell

. Minimal clinically important differences (MCID) and patient acceptable symptomatic state (PASS) for visual analog scales (VAS)measuring pain in patients treated for rotator cuff disease. J Shoulder Elbow Surg. 2009 Nov-Dec; 18(6): 927-32.

25.

Louwerens

Sierevelt

van Noort

van den Bekerom

. Evidence for minimally invasive therapies in the management of chronic calcific tendinopathy of the rotator cuff: A systematic review and meta-analysis. J Shoulder Elbow Surg. 2014 Aug; 23(8): 1240-9.

26.

Arirachakaran

Boonard

Yamaphai

Prommahachai

Kesprayura

Kongtharvonskul

. Extracorporeal shock wave therapy, ultrasound-guided percutaneous lavage, corticosteroid injection and combined treatment for the treatment of rotator cuff calcific tendinopathy: A network meta-analysis of RCTs. Eur J Orthop Surg Traumatol. 2017 Apr; 27(3): 381-390.

27.

Kim

Lee

Kim

Kong

. Which method is more effective in treatment of calcific tendinitis in the shoulder? Prospective randomized comparison between ultrasound-guided needling and extracorporeal shock wave therapy. J Shoulder Elbow Surg. 2014 Nov; 23(11): 1640-6.

28.

De Boer

Mocking

Nelissen

Van Kampen

Huijsmans

. Ultrasound guided Needling vs Radial Shockwave Therapy in calcific tendinitis of the shoulder: A prospective randomized trial. J Orthop. 2017 Aug 1; 14(4): 466-469.

29.

Hsieh

Lin

Hsu

Kuo

Liu

Chiang

Wang

. Comparison of the corticosteroid injection and hyaluronate in the treatment of chronic subacromial bursitis: A randomized controlled trial. Clin Rehabil. 2021 Sep; 35(9): 1305-1316.

30.

Muir

Corea

Beaupre

. Evaluating change in clinical status: Reliability and measures of agreement for the assessment of glenohumeral range of motion. N Am J Sports Phys Ther. 2010 Sep; 5(3): 98-110.

31.

Pan