Musculoskeletal Imaging • Original Research Vignesh et al. Ultrasound-Guided Percutaneous Treatment of Calcific Tendinitis
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Musculoskeletal Imaging Original Research
Efficacy of Ultrasound-Guided Percutaneous Needle Treatment of Calcific Tendinitis K. Nithin Vignesh1 Adam McDowall1 Nicole Simunovic2 Mohit Bhandari2 Hema N. Choudur 3 Vignesh KN, McDowall A, Simunovic N, Bhandari M, Choudur HN
OBJECTIVE. The purpose of this study was to conduct a systematic review of the efficacy of ultrasound-guided needle lavage in treating calcific tendinitis. MATERIALS AND METHODS. Two independent assessors searched medical databases and screened studies for eligibility. RESULTS. Eleven articles were included. Heterogeneity among included studies precluded meta-analysis. Results of randomized controlled trials suggested no difference in pain relief between needle lavage and other interventions, but the studies were of low quality. CONCLUSION. Additional high-quality evidence is required to determine the relative efficacy of ultrasound-guided needle lavage in the management of calcific tendinitis of the rotator cuff.
C
Keywords: calcific tendinitis, shoulder rotator cuff, systematic review, ultrasound-guided needle lavage DOI:10.2214/AJR.13.11935 Received August 21, 2013; accepted after revision April 25, 2014. M. Bhandari is funded in part by the Canada Research Chair. 1
McMaster University, Hamilton, ON, Canada.
2
Department of Clinical Epidemiology and Biostatistics, McMaster University, 293 Wellington St N, Ste 110, Hamilton, ON, Canada, L8L 8E7. Address correspondence to M. Bhandari ([email protected]). 3 Department of Radiology, McMaster University, Hamilton, ON, Canada.
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148
alcific tendinitis of the rotator cuff accounts for 7% of shoulder pain among adults [1–4]. Characterized by acute or chronic inflammation around crystal hydroxyapatite on the rotator cuff tendons, this disease usually affects adults older than 30–40 years [5]. The supraspinatus tendon appears to be most susceptible, being affected as much as 80% of the time [6]. The cause of the calcification is not clear [6]. Calcific tendinitis of the rotator cuff seriously affects patients’ independence, quality of life, and mobility for daily tasks. Understanding the efficacy of treatment options is imperative in improving patient care. Calcific tendinitis is considered a selfhealing condition in which the calcifications spontaneously resolve. The development of calcific tendinitis can be understood in terms of stages. First, the precalcific stage is asymptomatic and involves cellular changes at specific sites such that there is a predisposition to calcium deposition [7]. Next, calcium coalesces into deposits in the calcific stage [7]. An initial resting phase in which no pain is experienced is followed by a resorptive phase, which is the most painful [7]. Finally, there is a postcalcific stage in which the calcium disappears from the tendon, and no pain is experienced [7]. Some patients may have recurrent pain and disability that requires treatment, because their condition does not progress spontaneous-
ly from the calcific to the postcalcific stage. Nonoperative treatment is first indicated for such patients and may include therapeutic exercise and nonsteroidal antiinflammatory drugs for pain, extracorporeal shockwave therapy, and corticosteroid injection [5, 8, 9]. For patients whose condition does not improve with nonoperative treatment, removal of the calcification may be facilitated by ultrasound-guided needle lavage [6, 10, 11]. This minimally invasive treatment involves the use of one or two needles to perform lavage with or without aspiration of calcium deposits with an ultrasound probe to image the calcifications in real time [6, 11]. Calcifications can subsequently be fragmented and their removal facilitated by saline lavage. The advantages of sonography are that it is highly sensitive and that clinicians can accurately visualize and localize rotator cuff calcifications without exposure to harmful radiation from fluoroscopy, which was traditionally used through barbotage [10]. Calcifications can subsequently be fragmented and their removal facilitated by saline lavage. The size and softness of the calcification can be easily assessed and documented with ultrasound, allowing objective comparisons [2, 10]. The status of the surrounding tendon, including procedure-related tears, can also be accurately assessed, though procedure-related tears are infrequent. A tendon tear before the procedure is a contraindication to this in-
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Ultrasound-Guided Percutaneous Treatment of Calcific Tendinitis tervention. Overall, the benefit of revisiting this treatment method lies in its simplicity and relatively low risk to patients [2, 10]. Ultrasound-guided needle lavage probably has not been widely used because of a lack of comparisons of its effectiveness with that of alternative interventions with long-term findings, and no standard of care seems to exist. We undertook a systematic review to evaluate the efficacy of ultrasound-guided needle lavage compared with all other forms of treatment of calcific tendinitis of the rotator cuff.
TABLE 1: Search Strategy Term No.
Search Term
very low quality. Any discrepancies in quality assessment between the two reviewers were resolved through discussion when necessary.
1
Calcific tendinitis.mp.
2
exp Calcinosis/
Assessing Reviewer Agreement
3
Tendinitis.mp.
4
Calcification.mp.
5
Term 1 or 2 or 3 or 4
6
Humans/
7
Rotator Cuff/
8
Term 6 or 7
Materials and Methods Eligibility Criteria
9
Ultrasound.mp.
We established a priori eligibility criteria. No restrictions were placed on whether a study was published or unpublished, the type of study, or language. We included studies if they were conducted with patients with calcific tendinitis of the shoulder rotator cuff and if ultrasound-guided needle lavage was at least one of the interventions.
10
Lavage.mp.
11
Therapeutic Irrigation/
12
Sonography.fs.
13
Needle*.mp.
14
Term 9 or 10 or 11 or 12 or 13
15
Terms 5 and 8
16
Terms 14 and 15
During the study screening process, each reviewer graded each candidate study as include, exclude, or unsure. Reviewer agreement for these grades was assessed separately for three groups: studies excluded on the basis of the title alone, studies excluded on the basis of the title and the abstract, and studies in which the full-text version was reviewed. Reviewer agreement for each of these three groups was assessed with a weighted kappa statistic. This statistic addresses the possibility of chance agreement and is recognized as a widely accepted measure of agreement [14]. It is a means of emphasizing the differences that occur across major categories when multiple descriptors are used [14]. Practically speaking, the difference between include and exclude is more meaningful than that between include and unsure and should be treated as such in the statistical analysis. Nonweighted kappa statistics would otherwise treat all disagreements equally, which would bias the agreement values. In general, a kappa value of 0–0.2 indicates slight agreement; 0.21–0.4, fair agreement; 0.41–0.6, moderate agreement; and 0.61–0.8, substantial agreement. A score higher than 0.8 reflects almost perfect agreement [15]. An intraclass correlation coefficient (ICC) was calculated to determine interobserver agreement in the assessment of the methodologic quality of the included studies. We decided a priori that an ICC of 0.65 or greater should be accepted as adequate agreement. Both weighted kappa statistic and ICC were calculated with the statistical package SPSS (version 21.0.0, IBM SPSS).
Search Methods We searched the following databases: Ovid MEDLINE In-Process and Other Nonindexed Citations and Ovid MEDLINE (1946–2013), Ovid EMBASE (1980–2013), and Cochrane Central Register of Controlled Trials. In Cochrane and MEDLINE, subject-specific search strategies were combined to attain the most relevant results (Fig. 1). The search terms used in this review are shown in Table 1. One trial registry, ClinicalTrials.gov, was also reviewed to identify any potentially eligible ongoing or completed trials. No unpublished studies were located in the search.
Study Selection Two of us independently conducted title, abstract, and full-text screening based on a priori eligibility criteria. We discussed any discrepancies in inclusion choice and reached a consensus in all cases.
Data Collection and Extraction Process Two of us independently extracted all relevant information in the included studies. We extracted study characteristics, including study design, location, interventions studied, sample size of each arm, and outcomes, using a detailed data extraction form. Any differences in data extraction were resolved through discussion between us. We extracted the measure of central tendency (e.g., mean) and dispersion characteristic (e.g., range), when available, for all continuous variables. Outcomes of interest were as follows: pain measured with a scale or score before and after the intervention, degree of movement of the rotator cuff of the shoulder before and after the intervention,
and calcification size (diameter) of the deposits on the rotator cuff. Percentage changes were calculated for both ultrasound-guided needle lavage and other interventions to provide a standardized comparison of treatment effect.
Quality Assessment Two of us independently assessed the methodologic quality of each eligible study. Case-control and cohort study methodologic quality was assessed with the Newcastle-Ottawa scales for case-control and cohort studies [12]. These scales are used to grade studies on the basis of selection and comparability of the case and control groups and for ascertainment of exposure and follow-up. They are widely regarded as valid tools for assessing the quality of the two study types. On the scale, a maximum score of 9 can be awarded. We established a priori that a score of 8 or higher reflects high quality; 5–7, moderate quality; and 4 and lower, low quality. Case series included in our review were considered level 4, or low-quality, evidence overall. The randomized controlled trials included in this review were assessed for quality with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scale [13]. The scale is used to assess quality on the basis of allocation and blinding, follow-up, degree of consistency of effect between or within studies, and generalizability of outcomes to the population of interest. On the GRADE scale, randomized controlled trials can score a maximum of 7. In our study, a score of 4 points or more was regarded as high quality; 3, moderate; 2, low; and 1 or 0,
Results Results of the Search Our initial electronic search yielded 9771 articles from the MEDLINE, EMBASE, and Cochrane databases (Fig. 1). After removal of duplicate studies, 6681 articles were identified for screening. The screening was conducted in a stepwise manner based on title alone, title and abstract, and full text. On completion of the screening process, 11 articles were found eligible for this review. Despite attempts to contact the authors of two trials identified at ClinicalTrials.gov for more information, there was no response. Reviewer Agreement The two reviewers had substantial agreement across title (κ = 0.69; 95% CI, 0.62– 0.76), abstract (κ = 0.72; 95% CI, 0.55–0.89),
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Vignesh et al.
MEDLINE (n = 4450)
Cochrane (n = 0)
shows, all of the randomized controlled trials included in this study were of very low or low methodologic quality.
EMBASE (n = 5321) 3090 Duplicate articles
Title review (n = 6681)
Abstract review (n = 58)
Full-text review (n = 31)
Included trials (n = 11)
20 Studies excluded: • 11 abstracts and full texts were not available • 1 ultrasound was used as an imaging technique without needle lavage • 8 did not describe outcomes, but described surgical procedures
Fig. 1—Flowchart shows search method.
and full-text review (κ = 0.80; 95% CI, 0.63– 0.98). Agreement between reviewers in quality assessment was very good (ICC, 0.86; 95% CI, 0.31–0.98). Study Characteristics The sample sizes of the included studies ranged from 30 to 462 patients. Study designs included three randomized controlled trials, two cohort studies, one retrospective chart review, and five case series, all of which were generally low in quality (Table 2). Outcome measures among studies included pain, degree of movement, and calcification size. Heterogeneity among included studies precluded meta-analysis. Evidence for Ultrasound-Guided Needle Lavage: Randomized Controlled Trials Three randomized controlled trials were identified as eligible for inclusion in our review (n = 310 for the ultrasound-guided needle lavage arm, n = 313 for the comparator interventions arm) [5, 11, 16]. As Table 3 shows, all randomized controlled trials showed a decrease in pain after ultrasoundguided needle lavage, but only Zhu et al. [16] found the reduction in pain to be statistically significant (p ≤ 0.05) compared with
150
that achieved with ultrasound-guided needle punctures without aspiration. Sconfienza et al. [11] found no significant difference in outcome with different temperatures of saline solution used for ultrasound-guided needle lavage. Krasny et al. [5] found that combining high-energy shockwave therapy with ultrasound-guided needle lavage was associated with significantly greater reduction in pain and calcium deposition. As Table 2
Evidence for Ultrasound-Guided Needle Lavage: Observational Studies Three observational studies [2, 17, 18] were included in this review (n = 217). Chiou et al. [17] and De Zordo et al. [18] reported reductions in calcification size when ultrasound-guided needle lavage was used. Chiou et al. found that compared with conservative treatment, ultrasound-guided needle lavage was statistically superior in reducing chronic but not acute pain. Serafini et al. [2] found no statistical difference in pain reduction or degree of movement improvement when they compared ultrasound-guided needle lavage with no treatment (control group). These results are summarized in Table 3. The observational studies included in this review were deemed to be of low methodologic quality. Evidence for Ultrasound-Guided Needle Lavage: Case Series The case series (n = 264) in this review showed measurable reduction in pain and disability after treatment with ultrasoundguided needle lavage [6, 8, 10, 19]. Yoo et al. [9] (n = 30) explored the effects of ultrasound-guided needle lavage with corticosteroid injection on degree of improvement in movement and reduction in calcification size. Across the case series studies, ultrasoundguided needle lavage showed promise as a treatment option for relieving pain, improving degree of movement, and reducing calcification size. The detailed findings of each study are shown in Table 3.
TABLE 2: Characteristics of Included Studies Study Alna et al. 2001 [10]
Design Case series
Location Canada
Sample Size 30
Quality Score Low
Fusaro et al. 2011 [6]
Case series
Italy
106
Low
Farin et al. 1996 [19]
Case series
Finland
58
Low
Yoo et al. 2010 [9]
Case series
South Korea
30
Low
del Cura et al. 2007 [8]
Case series
Spain
70
Low
Chiou et al. 2001 [17]
Cohort (3 treatment groups)
Taiwan
40, 28, and 32
Low (3a)
Serafini et al. 2009 [2]
Cohort study
Italy
151 and 68
Low (3a)
Sconfienza et al. 2012 [11]
Randomized control trial
Italy
229 and 233
Very low (1b)
Krasny et al. 2005 [5]
Randomized control trial
Austria
40 and 40
Low (2b)
Zhu et al. 2008 [16]
Randomized control trial
China
41 and 40
Very low (1b)
De Zordo et al. 2011 [18]
Case-control
Canada
34
Low (3a)
aNewcastle-Ottawa scale.
bGrading of Recommendations Assessment, Development and Evaluation (GRADE) score.
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Ultrasound-Guided Percutaneous Treatment of Calcific Tendinitis
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TABLE 3: Results of Included Studies Categorized by Hierarchy of Evidence
Study
Range of Pain Motion Reduction in Improvement Improvement Calcification for 1 y (%) (%) (%)
Intervention
Randomized controlled trials (highest order of evidence) Sconfienza et al. [11]
Krasny et al. [5]
Zhu et al. [16]
Ultrasound-guided needle lavage with warm saline solution
66a
NA
NA
Ultrasound-guided needle lavage with room temperature saline solution
65
NA
NA
High-energy shockwave therapy
89 (4.1 mo)
55
NA
Ultrasound-guided needle lavage followed by high-energy shockwave therapy
99 (4.1 mo)
71
NA
Ultrasound-guided needle punctures
47b
NA
NA
Ultrasound-guided needle puncture and aspiration
51b
NA
NA
1, Conservative treatment of chronic pain; 2, conservative treatment of acute pain
NA
NA
50
Ultrasound-guided needle lavage
NA
NA
50
Observational studies (middle-order evidence) Chiou et al. [17]
Serafini et al. [2] De Zordo et al. [18]
No treatment
70 (10 y)
37 (10 y)
NA
Ultrasound-guided needle lavage
48 (10 y)
20 (10 y)
NA
Ultrasound-guided needle lavage
NA
NA
62 (with ≥ 80% reduction)
Case series (lowest order of evidence) Alna et al. [10]
Ultrasound-guided needle lavage
30 (1 mo)
NA
31
Fusaro et al. [6]
Ultrasound-guided needle lavage
31 (1 mo)
41
NA
Farin et al. [19]
Ultrasound-guided needle lavage
NA
NA
74
del Cura et al. [8]
Ultrasound-guided needle lavage
69
NA
NA
Yoo et al. [9]
Ultrasound-guided needle lavage with corticosteroid injection
NA
64
59
Note—NA = not available. aImprovement in visual analog scale score. bSix-month follow-up available.
Discussion Although the existing studies have shown ultrasound-guided needle lavage to be a promising treatment option, our systematic review showed insufficient evidence to conclude that ultrasound-guided needle lavage is superior to other methods evaluated for the management of calcific tendinitis. Owing to variations in treatment approaches and lack of high-quality evidence, the observed reductions in pain, disability, and calcification size and improvement in degree of move-
ment found in some studies cannot be conclusively attributed to ultrasound-guide needle lavage alone. The effect observed may be a result of natural recovery processes over time. Furthermore, needle fenestration may be contributing to the observed therapeutic effect [20]. Fenestration, in which a needle is passed repeatedly through the affected tendon, appears to relieve symptoms in individuals with chronic tendinosis or tendinopathy [20]. This treatment differs from those included in this review in that it does not in-
volve lavage with saline solution or aspiration of calcifications. It may be a confounder, however, because it entails a similar technique. Serafini et al. [2] observed no significant difference in pain after a follow-up period of 10 years. The randomized controlled trials in this review were of low quality and did not show statistically significant differences in treatment effect for ultrasoundguided needle lavage. Limitations Our systematic review had limitations. Most of the available evidence was of low quality and observational. Observational studies are prone to selection bias, information bias, analytic bias, and differential loss to follow-up. Confounders and a lack of control groups may play a role in exaggerating treatment effects. Furthermore, although we made efforts to communicate with authors of studies for which no full text was available or through trial registries, we were not successful and were not able to incorporate unpublished research into our findings. Therefore, our review may be subject to publication bias because the true effect among all existing studies cannot be fully determined. Implications Further high-quality research is necessary to determine the efficacy of ultrasound-guided needle lavage as a treatment option for calcific tendinitis of the rotator cuff. Overall, however, ultrasound-guided needle lavage may be indicated because of its apparent low risk and its minimally invasive nature [9, 21]. In addition, the procedure is low in cost, relatively easy for clinicians to perform on an outpatient basis, and requires minimal time. Ultrasoundguided needle lavage may be effective if the appropriate, eligible patient is identified [9, 21]. In particular, patients with soft solitary calcifications smaller than 1 cm in diameter without tendon tears tend to respond well to this treatment [6, 10, 11]. Removing the source of impingement, namely, the calcium deposits on the rotator cuff tendons, remains a key objective of treatment of calcific tendinitis [6, 10, 11]. This ultimately is the goal of ultrasound-guided needle lavage, whereas other interventions focus more on the symptoms of pain and disability [6, 10, 11]. Although these benefits do exist and the results of the included studies suggest ultrasound-guided needle lavage may have a positive therapeutic effect, it is difficult to ascertain whether it is superior to other interventions.
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Vignesh et al. Planning a Future Trial Considering the lack of high-quality evidence to support ultrasound-guided needle lavage, we highlight the need for a properly conducted randomized controlled trial and the characteristics of such a trial. Overall, such a trial is justified to determine the effectiveness of treatment of patients whose condition does not improve with nonoperative treatment and remains in the calcific stage [7]. Evidence suggests that 30% of patients who undergo nonoperative treatment have persistent symptoms [22]. Certain factors appear to contribute to the negative prognosis of these patients, including high volume of calcium deposits, bilateral occurrence, localization at the anterior portion of the acromion, and medial (subacromial) extension [22]. Furthermore, it has been previously described that other treatment options, such as needling and removal of calcific deposits, should be considered if the nonoperative treatment fails after 6 months [22]. Thus, the best course of treatment of patients with chronic painful shoulders from persistent calcific tendinitis should be elucidated. First, a randomized controlled trial should include patients with the diagnosis of calcific tendinitis of the rotator cuff and allocate them to one of two treatment arms. One of these arms must be ultrasound-guided needle lavage treatment, and the other, needle fenestration treatment alone (no lavage). Because of the lack of proper randomization sequences and allocation concealment existent in the studies included in this review, a future trial should blind participants and assessors, given that clinicians and surgeons cannot be blinded to the treatment group to which a patient is assigned. In addition, efforts should be made in the allocation process to ensure a balance in patient characteristics between the two study groups. The two interventions between which comparisons of effectiveness would be made could be ultrasound-guided needle lavage and conservative treatment. A large enough number of patients would have to be recruited to ensure sufficient statistical power and the capture of significant results.
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Conclusion Overall our review highlights the need for more high-quality randomized controlled trials comparing ultrasound-guided needle lavage with all other forms of treatment to determine the true efficacy of this minimally invasive interventional procedure. References 1. Speed CA, Hazleman BL. Calcific tendinitis of the shoulder. N Engl J Med 1999; 340:1582–1584 2. Serafini G, Sconfienza LM, Lacelli F, Silvestri E, Aliprandi A, Sardanelli F. Rotator cuff calcific tendonitis: short-term and 10-year outcomes after two-needle US-guided percutaneous treatment— nonrandomized controlled trial. Radiology 2009; 252:157–164 3. Uhthoff HK, Sarkar K. Calcifying tendinitis. Baillieres Clin Rheumatol 1989; 3:567–581 4. Mole D, Gonzalvez M, Roche O, Scarlat M. Introduction to calcifying tendinitis. In: Gazielly DF, Gleyze P, Thomas T, eds. The cuff. Paris, France: Elsevier, 1997:141–143 5. Krasny C, Enenkel M, Aigner N, Wlk M, Landsiedl F. Ultrasound-guided needling combined with shock-wave therapy for the treatment of calcifying tendonitis of the shoulder. J Bone Joint Surg Br 2005; 87:501–507 6. Fusaro I, Orsini S, Diani S, Saffioti G, Zaccarelli L, Galetti S. Functional results in calcific tendinitis of the shoulder treated with rehabilitation after ultrasonic-guided approach. Musculoskelet Surg 2011; 95(suppl 1):S31–S36 7. Kachewar SG, Kulkarni DS. Calcific tendinitis of the rotator cuff: a review. J Clin Diagn Res 2013; 7:1482–1485 8. del Cura JL, Torre I, Zabala R, Legorburu A. Sonographically guided percutaneous needle lavage in calcific tendinitis of the shoulder: short and longterm results. AJR 2007; 189:[web]W129–W134 9. Yoo JC, Koh KH, Park WH, Park JC, Kim SM, Yoon YC. The outcome of ultrasound-guided needle decompression and steroid injection in calcific tendinitis. J Shoulder Elbow Surg 2010; 19:596–600 10. Alna R, Cardinal E, Bureau NJ, Aubin B, Brassard P. Calcific shoulder tendinitis: treatment with modified US-guided fine-needle technique. Radiology 2001; 221:455–461
11. Sconfienza LM, Bandirali M, Serafini G, et al. Rotator cuff calcific tendonitis: does warm saline solution improve the short-term outcome of double-needle US-guided treatment? Radiology 2012; 262:560–566 12. Wells GA, Shea B, O’Connell D, et al. The Newcastle-Ottawa scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. Ottawa Hospital Research Institute website. www. ohri.ca/programs/clinical_epidemiology/oxford. asp. Accessed March 1, 2013 13. Guyatt GH, Oxman AD, Vist GS, et al. GRADE: an emerging consensus of rating quality of evidence and strength of recommendations. BMJ 2008; 336:924–926 14. Cohen J. Weighted kappa: nominal scale agreement with provision for scaled disagreement or partial credit. Psychol Bull 1968; 70:213–220 15. Viera AJ, Garrett JM. Understanding interobserver agreement: the kappa statistic. Fam Med 2005; 37:360–363 16. Zhu J, Jiang Y, Hu Y, Xing C, Hu B. Evaluating the long-term effect of ultrasound-guided needle puncture without aspiration on calcifying supraspinatus tendinitis. Adv Ther 2008; 25:1229–1234 17. Chiou HJ, Chou YH, Wu JJ, et al. The role of high-resolution ultrasonography in management of calcific tendonitis of the rotator cuff. Ultrasound Med Biol 2001; 27:735–743 18. De Zordo T, Ahmad N, Ødegaard F, et al. USguided therapy of calcific tendinopathy: clinical and radiological outcome assessment in shoulder and non-shoulder tendons. Ultraschall Med 2011; 32(suppl 1):S117–S123 19. Farin PU, Rasanen H, Jaroma H, Harju A. Rotator cuff calcifications: treatment with ultrasoundguided percutaneous needle aspiration and lavage. Skeletal Radiol 1996; 25:551–554 20. Chiavaras MM, Jacobson JA. Ultrasound-guided tendon fenestration. Semin Musculoskelet Radiol 2013; 17:85–90 21. Oliva F, Via AG, Maffulli N. Physiopathology of intratendinous calcific deposition. BMC Med 2012; 10:95 22. Ogon P, Suedkamp NP, Jaeger M, Izadpanah K, Koestler W, Maier D. Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder. Arthritis Rheum 2009; 60:2978–2984
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Musculoskeletal Imaging Original Research
Efficacy of Ultrasound-Guided Percutaneous Needle Treatment of Calcific Tendinitis K. Nithin Vignesh1 Adam McDowall1 Nicole Simunovic2 Mohit Bhandari2 Hema N. Choudur 3 Vignesh KN, McDowall A, Simunovic N, Bhandari M, Choudur HN
OBJECTIVE. The purpose of this study was to conduct a systematic review of the efficacy of ultrasound-guided needle lavage in treating calcific tendinitis. MATERIALS AND METHODS. Two independent assessors searched medical databases and screened studies for eligibility. RESULTS. Eleven articles were included. Heterogeneity among included studies precluded meta-analysis. Results of randomized controlled trials suggested no difference in pain relief between needle lavage and other interventions, but the studies were of low quality. CONCLUSION. Additional high-quality evidence is required to determine the relative efficacy of ultrasound-guided needle lavage in the management of calcific tendinitis of the rotator cuff.
C
Keywords: calcific tendinitis, shoulder rotator cuff, systematic review, ultrasound-guided needle lavage DOI:10.2214/AJR.13.11935 Received August 21, 2013; accepted after revision April 25, 2014. M. Bhandari is funded in part by the Canada Research Chair. 1
McMaster University, Hamilton, ON, Canada.
2
Department of Clinical Epidemiology and Biostatistics, McMaster University, 293 Wellington St N, Ste 110, Hamilton, ON, Canada, L8L 8E7. Address correspondence to M. Bhandari ([email protected]). 3 Department of Radiology, McMaster University, Hamilton, ON, Canada.
AJR 2015; 204:148–152 0361–803X/15/2041–148 © American Roentgen Ray Society
148
alcific tendinitis of the rotator cuff accounts for 7% of shoulder pain among adults [1–4]. Characterized by acute or chronic inflammation around crystal hydroxyapatite on the rotator cuff tendons, this disease usually affects adults older than 30–40 years [5]. The supraspinatus tendon appears to be most susceptible, being affected as much as 80% of the time [6]. The cause of the calcification is not clear [6]. Calcific tendinitis of the rotator cuff seriously affects patients’ independence, quality of life, and mobility for daily tasks. Understanding the efficacy of treatment options is imperative in improving patient care. Calcific tendinitis is considered a selfhealing condition in which the calcifications spontaneously resolve. The development of calcific tendinitis can be understood in terms of stages. First, the precalcific stage is asymptomatic and involves cellular changes at specific sites such that there is a predisposition to calcium deposition [7]. Next, calcium coalesces into deposits in the calcific stage [7]. An initial resting phase in which no pain is experienced is followed by a resorptive phase, which is the most painful [7]. Finally, there is a postcalcific stage in which the calcium disappears from the tendon, and no pain is experienced [7]. Some patients may have recurrent pain and disability that requires treatment, because their condition does not progress spontaneous-
ly from the calcific to the postcalcific stage. Nonoperative treatment is first indicated for such patients and may include therapeutic exercise and nonsteroidal antiinflammatory drugs for pain, extracorporeal shockwave therapy, and corticosteroid injection [5, 8, 9]. For patients whose condition does not improve with nonoperative treatment, removal of the calcification may be facilitated by ultrasound-guided needle lavage [6, 10, 11]. This minimally invasive treatment involves the use of one or two needles to perform lavage with or without aspiration of calcium deposits with an ultrasound probe to image the calcifications in real time [6, 11]. Calcifications can subsequently be fragmented and their removal facilitated by saline lavage. The advantages of sonography are that it is highly sensitive and that clinicians can accurately visualize and localize rotator cuff calcifications without exposure to harmful radiation from fluoroscopy, which was traditionally used through barbotage [10]. Calcifications can subsequently be fragmented and their removal facilitated by saline lavage. The size and softness of the calcification can be easily assessed and documented with ultrasound, allowing objective comparisons [2, 10]. The status of the surrounding tendon, including procedure-related tears, can also be accurately assessed, though procedure-related tears are infrequent. A tendon tear before the procedure is a contraindication to this in-
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Ultrasound-Guided Percutaneous Treatment of Calcific Tendinitis tervention. Overall, the benefit of revisiting this treatment method lies in its simplicity and relatively low risk to patients [2, 10]. Ultrasound-guided needle lavage probably has not been widely used because of a lack of comparisons of its effectiveness with that of alternative interventions with long-term findings, and no standard of care seems to exist. We undertook a systematic review to evaluate the efficacy of ultrasound-guided needle lavage compared with all other forms of treatment of calcific tendinitis of the rotator cuff.
TABLE 1: Search Strategy Term No.
Search Term
very low quality. Any discrepancies in quality assessment between the two reviewers were resolved through discussion when necessary.
1
Calcific tendinitis.mp.
2
exp Calcinosis/
Assessing Reviewer Agreement
3
Tendinitis.mp.
4
Calcification.mp.
5
Term 1 or 2 or 3 or 4
6
Humans/
7
Rotator Cuff/
8
Term 6 or 7
Materials and Methods Eligibility Criteria
9
Ultrasound.mp.
We established a priori eligibility criteria. No restrictions were placed on whether a study was published or unpublished, the type of study, or language. We included studies if they were conducted with patients with calcific tendinitis of the shoulder rotator cuff and if ultrasound-guided needle lavage was at least one of the interventions.
10
Lavage.mp.
11
Therapeutic Irrigation/
12
Sonography.fs.
13
Needle*.mp.
14
Term 9 or 10 or 11 or 12 or 13
15
Terms 5 and 8
16
Terms 14 and 15
During the study screening process, each reviewer graded each candidate study as include, exclude, or unsure. Reviewer agreement for these grades was assessed separately for three groups: studies excluded on the basis of the title alone, studies excluded on the basis of the title and the abstract, and studies in which the full-text version was reviewed. Reviewer agreement for each of these three groups was assessed with a weighted kappa statistic. This statistic addresses the possibility of chance agreement and is recognized as a widely accepted measure of agreement [14]. It is a means of emphasizing the differences that occur across major categories when multiple descriptors are used [14]. Practically speaking, the difference between include and exclude is more meaningful than that between include and unsure and should be treated as such in the statistical analysis. Nonweighted kappa statistics would otherwise treat all disagreements equally, which would bias the agreement values. In general, a kappa value of 0–0.2 indicates slight agreement; 0.21–0.4, fair agreement; 0.41–0.6, moderate agreement; and 0.61–0.8, substantial agreement. A score higher than 0.8 reflects almost perfect agreement [15]. An intraclass correlation coefficient (ICC) was calculated to determine interobserver agreement in the assessment of the methodologic quality of the included studies. We decided a priori that an ICC of 0.65 or greater should be accepted as adequate agreement. Both weighted kappa statistic and ICC were calculated with the statistical package SPSS (version 21.0.0, IBM SPSS).
Search Methods We searched the following databases: Ovid MEDLINE In-Process and Other Nonindexed Citations and Ovid MEDLINE (1946–2013), Ovid EMBASE (1980–2013), and Cochrane Central Register of Controlled Trials. In Cochrane and MEDLINE, subject-specific search strategies were combined to attain the most relevant results (Fig. 1). The search terms used in this review are shown in Table 1. One trial registry, ClinicalTrials.gov, was also reviewed to identify any potentially eligible ongoing or completed trials. No unpublished studies were located in the search.
Study Selection Two of us independently conducted title, abstract, and full-text screening based on a priori eligibility criteria. We discussed any discrepancies in inclusion choice and reached a consensus in all cases.
Data Collection and Extraction Process Two of us independently extracted all relevant information in the included studies. We extracted study characteristics, including study design, location, interventions studied, sample size of each arm, and outcomes, using a detailed data extraction form. Any differences in data extraction were resolved through discussion between us. We extracted the measure of central tendency (e.g., mean) and dispersion characteristic (e.g., range), when available, for all continuous variables. Outcomes of interest were as follows: pain measured with a scale or score before and after the intervention, degree of movement of the rotator cuff of the shoulder before and after the intervention,
and calcification size (diameter) of the deposits on the rotator cuff. Percentage changes were calculated for both ultrasound-guided needle lavage and other interventions to provide a standardized comparison of treatment effect.
Quality Assessment Two of us independently assessed the methodologic quality of each eligible study. Case-control and cohort study methodologic quality was assessed with the Newcastle-Ottawa scales for case-control and cohort studies [12]. These scales are used to grade studies on the basis of selection and comparability of the case and control groups and for ascertainment of exposure and follow-up. They are widely regarded as valid tools for assessing the quality of the two study types. On the scale, a maximum score of 9 can be awarded. We established a priori that a score of 8 or higher reflects high quality; 5–7, moderate quality; and 4 and lower, low quality. Case series included in our review were considered level 4, or low-quality, evidence overall. The randomized controlled trials included in this review were assessed for quality with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scale [13]. The scale is used to assess quality on the basis of allocation and blinding, follow-up, degree of consistency of effect between or within studies, and generalizability of outcomes to the population of interest. On the GRADE scale, randomized controlled trials can score a maximum of 7. In our study, a score of 4 points or more was regarded as high quality; 3, moderate; 2, low; and 1 or 0,
Results Results of the Search Our initial electronic search yielded 9771 articles from the MEDLINE, EMBASE, and Cochrane databases (Fig. 1). After removal of duplicate studies, 6681 articles were identified for screening. The screening was conducted in a stepwise manner based on title alone, title and abstract, and full text. On completion of the screening process, 11 articles were found eligible for this review. Despite attempts to contact the authors of two trials identified at ClinicalTrials.gov for more information, there was no response. Reviewer Agreement The two reviewers had substantial agreement across title (κ = 0.69; 95% CI, 0.62– 0.76), abstract (κ = 0.72; 95% CI, 0.55–0.89),
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Vignesh et al.
MEDLINE (n = 4450)
Cochrane (n = 0)
shows, all of the randomized controlled trials included in this study were of very low or low methodologic quality.
EMBASE (n = 5321) 3090 Duplicate articles
Title review (n = 6681)
Abstract review (n = 58)
Full-text review (n = 31)
Included trials (n = 11)
20 Studies excluded: • 11 abstracts and full texts were not available • 1 ultrasound was used as an imaging technique without needle lavage • 8 did not describe outcomes, but described surgical procedures
Fig. 1—Flowchart shows search method.
and full-text review (κ = 0.80; 95% CI, 0.63– 0.98). Agreement between reviewers in quality assessment was very good (ICC, 0.86; 95% CI, 0.31–0.98). Study Characteristics The sample sizes of the included studies ranged from 30 to 462 patients. Study designs included three randomized controlled trials, two cohort studies, one retrospective chart review, and five case series, all of which were generally low in quality (Table 2). Outcome measures among studies included pain, degree of movement, and calcification size. Heterogeneity among included studies precluded meta-analysis. Evidence for Ultrasound-Guided Needle Lavage: Randomized Controlled Trials Three randomized controlled trials were identified as eligible for inclusion in our review (n = 310 for the ultrasound-guided needle lavage arm, n = 313 for the comparator interventions arm) [5, 11, 16]. As Table 3 shows, all randomized controlled trials showed a decrease in pain after ultrasoundguided needle lavage, but only Zhu et al. [16] found the reduction in pain to be statistically significant (p ≤ 0.05) compared with
150
that achieved with ultrasound-guided needle punctures without aspiration. Sconfienza et al. [11] found no significant difference in outcome with different temperatures of saline solution used for ultrasound-guided needle lavage. Krasny et al. [5] found that combining high-energy shockwave therapy with ultrasound-guided needle lavage was associated with significantly greater reduction in pain and calcium deposition. As Table 2
Evidence for Ultrasound-Guided Needle Lavage: Observational Studies Three observational studies [2, 17, 18] were included in this review (n = 217). Chiou et al. [17] and De Zordo et al. [18] reported reductions in calcification size when ultrasound-guided needle lavage was used. Chiou et al. found that compared with conservative treatment, ultrasound-guided needle lavage was statistically superior in reducing chronic but not acute pain. Serafini et al. [2] found no statistical difference in pain reduction or degree of movement improvement when they compared ultrasound-guided needle lavage with no treatment (control group). These results are summarized in Table 3. The observational studies included in this review were deemed to be of low methodologic quality. Evidence for Ultrasound-Guided Needle Lavage: Case Series The case series (n = 264) in this review showed measurable reduction in pain and disability after treatment with ultrasoundguided needle lavage [6, 8, 10, 19]. Yoo et al. [9] (n = 30) explored the effects of ultrasound-guided needle lavage with corticosteroid injection on degree of improvement in movement and reduction in calcification size. Across the case series studies, ultrasoundguided needle lavage showed promise as a treatment option for relieving pain, improving degree of movement, and reducing calcification size. The detailed findings of each study are shown in Table 3.
TABLE 2: Characteristics of Included Studies Study Alna et al. 2001 [10]
Design Case series
Location Canada
Sample Size 30
Quality Score Low
Fusaro et al. 2011 [6]
Case series
Italy
106
Low
Farin et al. 1996 [19]
Case series
Finland
58
Low
Yoo et al. 2010 [9]
Case series
South Korea
30
Low
del Cura et al. 2007 [8]
Case series
Spain
70
Low
Chiou et al. 2001 [17]
Cohort (3 treatment groups)
Taiwan
40, 28, and 32
Low (3a)
Serafini et al. 2009 [2]
Cohort study
Italy
151 and 68
Low (3a)
Sconfienza et al. 2012 [11]
Randomized control trial
Italy
229 and 233
Very low (1b)
Krasny et al. 2005 [5]
Randomized control trial
Austria
40 and 40
Low (2b)
Zhu et al. 2008 [16]
Randomized control trial
China
41 and 40
Very low (1b)
De Zordo et al. 2011 [18]
Case-control
Canada
34
Low (3a)
aNewcastle-Ottawa scale.
bGrading of Recommendations Assessment, Development and Evaluation (GRADE) score.
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Ultrasound-Guided Percutaneous Treatment of Calcific Tendinitis
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TABLE 3: Results of Included Studies Categorized by Hierarchy of Evidence
Study
Range of Pain Motion Reduction in Improvement Improvement Calcification for 1 y (%) (%) (%)
Intervention
Randomized controlled trials (highest order of evidence) Sconfienza et al. [11]
Krasny et al. [5]
Zhu et al. [16]
Ultrasound-guided needle lavage with warm saline solution
66a
NA
NA
Ultrasound-guided needle lavage with room temperature saline solution
65
NA
NA
High-energy shockwave therapy
89 (4.1 mo)
55
NA
Ultrasound-guided needle lavage followed by high-energy shockwave therapy
99 (4.1 mo)
71
NA
Ultrasound-guided needle punctures
47b
NA
NA
Ultrasound-guided needle puncture and aspiration
51b
NA
NA
1, Conservative treatment of chronic pain; 2, conservative treatment of acute pain
NA
NA
50
Ultrasound-guided needle lavage
NA
NA
50
Observational studies (middle-order evidence) Chiou et al. [17]
Serafini et al. [2] De Zordo et al. [18]
No treatment
70 (10 y)
37 (10 y)
NA
Ultrasound-guided needle lavage
48 (10 y)
20 (10 y)
NA
Ultrasound-guided needle lavage
NA
NA
62 (with ≥ 80% reduction)
Case series (lowest order of evidence) Alna et al. [10]
Ultrasound-guided needle lavage
30 (1 mo)
NA
31
Fusaro et al. [6]
Ultrasound-guided needle lavage
31 (1 mo)
41
NA
Farin et al. [19]
Ultrasound-guided needle lavage
NA
NA
74
del Cura et al. [8]
Ultrasound-guided needle lavage
69
NA
NA
Yoo et al. [9]
Ultrasound-guided needle lavage with corticosteroid injection
NA
64
59
Note—NA = not available. aImprovement in visual analog scale score. bSix-month follow-up available.
Discussion Although the existing studies have shown ultrasound-guided needle lavage to be a promising treatment option, our systematic review showed insufficient evidence to conclude that ultrasound-guided needle lavage is superior to other methods evaluated for the management of calcific tendinitis. Owing to variations in treatment approaches and lack of high-quality evidence, the observed reductions in pain, disability, and calcification size and improvement in degree of move-
ment found in some studies cannot be conclusively attributed to ultrasound-guide needle lavage alone. The effect observed may be a result of natural recovery processes over time. Furthermore, needle fenestration may be contributing to the observed therapeutic effect [20]. Fenestration, in which a needle is passed repeatedly through the affected tendon, appears to relieve symptoms in individuals with chronic tendinosis or tendinopathy [20]. This treatment differs from those included in this review in that it does not in-
volve lavage with saline solution or aspiration of calcifications. It may be a confounder, however, because it entails a similar technique. Serafini et al. [2] observed no significant difference in pain after a follow-up period of 10 years. The randomized controlled trials in this review were of low quality and did not show statistically significant differences in treatment effect for ultrasoundguided needle lavage. Limitations Our systematic review had limitations. Most of the available evidence was of low quality and observational. Observational studies are prone to selection bias, information bias, analytic bias, and differential loss to follow-up. Confounders and a lack of control groups may play a role in exaggerating treatment effects. Furthermore, although we made efforts to communicate with authors of studies for which no full text was available or through trial registries, we were not successful and were not able to incorporate unpublished research into our findings. Therefore, our review may be subject to publication bias because the true effect among all existing studies cannot be fully determined. Implications Further high-quality research is necessary to determine the efficacy of ultrasound-guided needle lavage as a treatment option for calcific tendinitis of the rotator cuff. Overall, however, ultrasound-guided needle lavage may be indicated because of its apparent low risk and its minimally invasive nature [9, 21]. In addition, the procedure is low in cost, relatively easy for clinicians to perform on an outpatient basis, and requires minimal time. Ultrasoundguided needle lavage may be effective if the appropriate, eligible patient is identified [9, 21]. In particular, patients with soft solitary calcifications smaller than 1 cm in diameter without tendon tears tend to respond well to this treatment [6, 10, 11]. Removing the source of impingement, namely, the calcium deposits on the rotator cuff tendons, remains a key objective of treatment of calcific tendinitis [6, 10, 11]. This ultimately is the goal of ultrasound-guided needle lavage, whereas other interventions focus more on the symptoms of pain and disability [6, 10, 11]. Although these benefits do exist and the results of the included studies suggest ultrasound-guided needle lavage may have a positive therapeutic effect, it is difficult to ascertain whether it is superior to other interventions.
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Vignesh et al. Planning a Future Trial Considering the lack of high-quality evidence to support ultrasound-guided needle lavage, we highlight the need for a properly conducted randomized controlled trial and the characteristics of such a trial. Overall, such a trial is justified to determine the effectiveness of treatment of patients whose condition does not improve with nonoperative treatment and remains in the calcific stage [7]. Evidence suggests that 30% of patients who undergo nonoperative treatment have persistent symptoms [22]. Certain factors appear to contribute to the negative prognosis of these patients, including high volume of calcium deposits, bilateral occurrence, localization at the anterior portion of the acromion, and medial (subacromial) extension [22]. Furthermore, it has been previously described that other treatment options, such as needling and removal of calcific deposits, should be considered if the nonoperative treatment fails after 6 months [22]. Thus, the best course of treatment of patients with chronic painful shoulders from persistent calcific tendinitis should be elucidated. First, a randomized controlled trial should include patients with the diagnosis of calcific tendinitis of the rotator cuff and allocate them to one of two treatment arms. One of these arms must be ultrasound-guided needle lavage treatment, and the other, needle fenestration treatment alone (no lavage). Because of the lack of proper randomization sequences and allocation concealment existent in the studies included in this review, a future trial should blind participants and assessors, given that clinicians and surgeons cannot be blinded to the treatment group to which a patient is assigned. In addition, efforts should be made in the allocation process to ensure a balance in patient characteristics between the two study groups. The two interventions between which comparisons of effectiveness would be made could be ultrasound-guided needle lavage and conservative treatment. A large enough number of patients would have to be recruited to ensure sufficient statistical power and the capture of significant results.
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Conclusion Overall our review highlights the need for more high-quality randomized controlled trials comparing ultrasound-guided needle lavage with all other forms of treatment to determine the true efficacy of this minimally invasive interventional procedure. References 1. Speed CA, Hazleman BL. Calcific tendinitis of the shoulder. N Engl J Med 1999; 340:1582–1584 2. Serafini G, Sconfienza LM, Lacelli F, Silvestri E, Aliprandi A, Sardanelli F. Rotator cuff calcific tendonitis: short-term and 10-year outcomes after two-needle US-guided percutaneous treatment— nonrandomized controlled trial. Radiology 2009; 252:157–164 3. Uhthoff HK, Sarkar K. Calcifying tendinitis. Baillieres Clin Rheumatol 1989; 3:567–581 4. Mole D, Gonzalvez M, Roche O, Scarlat M. Introduction to calcifying tendinitis. In: Gazielly DF, Gleyze P, Thomas T, eds. The cuff. Paris, France: Elsevier, 1997:141–143 5. Krasny C, Enenkel M, Aigner N, Wlk M, Landsiedl F. Ultrasound-guided needling combined with shock-wave therapy for the treatment of calcifying tendonitis of the shoulder. J Bone Joint Surg Br 2005; 87:501–507 6. Fusaro I, Orsini S, Diani S, Saffioti G, Zaccarelli L, Galetti S. Functional results in calcific tendinitis of the shoulder treated with rehabilitation after ultrasonic-guided approach. Musculoskelet Surg 2011; 95(suppl 1):S31–S36 7. Kachewar SG, Kulkarni DS. Calcific tendinitis of the rotator cuff: a review. J Clin Diagn Res 2013; 7:1482–1485 8. del Cura JL, Torre I, Zabala R, Legorburu A. Sonographically guided percutaneous needle lavage in calcific tendinitis of the shoulder: short and longterm results. AJR 2007; 189:[web]W129–W134 9. Yoo JC, Koh KH, Park WH, Park JC, Kim SM, Yoon YC. The outcome of ultrasound-guided needle decompression and steroid injection in calcific tendinitis. J Shoulder Elbow Surg 2010; 19:596–600 10. Alna R, Cardinal E, Bureau NJ, Aubin B, Brassard P. Calcific shoulder tendinitis: treatment with modified US-guided fine-needle technique. Radiology 2001; 221:455–461
11. Sconfienza LM, Bandirali M, Serafini G, et al. Rotator cuff calcific tendonitis: does warm saline solution improve the short-term outcome of double-needle US-guided treatment? Radiology 2012; 262:560–566 12. Wells GA, Shea B, O’Connell D, et al. The Newcastle-Ottawa scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. Ottawa Hospital Research Institute website. www. ohri.ca/programs/clinical_epidemiology/oxford. asp. Accessed March 1, 2013 13. Guyatt GH, Oxman AD, Vist GS, et al. GRADE: an emerging consensus of rating quality of evidence and strength of recommendations. BMJ 2008; 336:924–926 14. Cohen J. Weighted kappa: nominal scale agreement with provision for scaled disagreement or partial credit. Psychol Bull 1968; 70:213–220 15. Viera AJ, Garrett JM. Understanding interobserver agreement: the kappa statistic. Fam Med 2005; 37:360–363 16. Zhu J, Jiang Y, Hu Y, Xing C, Hu B. Evaluating the long-term effect of ultrasound-guided needle puncture without aspiration on calcifying supraspinatus tendinitis. Adv Ther 2008; 25:1229–1234 17. Chiou HJ, Chou YH, Wu JJ, et al. The role of high-resolution ultrasonography in management of calcific tendonitis of the rotator cuff. Ultrasound Med Biol 2001; 27:735–743 18. De Zordo T, Ahmad N, Ødegaard F, et al. USguided therapy of calcific tendinopathy: clinical and radiological outcome assessment in shoulder and non-shoulder tendons. Ultraschall Med 2011; 32(suppl 1):S117–S123 19. Farin PU, Rasanen H, Jaroma H, Harju A. Rotator cuff calcifications: treatment with ultrasoundguided percutaneous needle aspiration and lavage. Skeletal Radiol 1996; 25:551–554 20. Chiavaras MM, Jacobson JA. Ultrasound-guided tendon fenestration. Semin Musculoskelet Radiol 2013; 17:85–90 21. Oliva F, Via AG, Maffulli N. Physiopathology of intratendinous calcific deposition. BMC Med 2012; 10:95 22. Ogon P, Suedkamp NP, Jaeger M, Izadpanah K, Koestler W, Maier D. Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder. Arthritis Rheum 2009; 60:2978–2984
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