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Radiologic course of the calcific deposits in calcific tendinitis of the shoulder: Does the initial radiologic aspect affect the final results?
J Shoulder Elbow Surg (2010) 19, 267-272
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Radiologic course of the calcific deposits in calcific tendinitis of the shoulder: Does the initial radiologic aspect affect the final results? Nam Su Cho, MD, Bong Gun Lee, MD, Yong Girl Rhee, MD* Shoulder & Elbow Clinic, Department of Orthopaedic Surgery, Kyung Hee University School of Medicine, Seoul, Korea Hypothesis: Although conservative treatment is the first option for the treatment of calcific tendinitis, only a few reports have described its results, without documenting the radiologic changes over time of calcific deposits. We hypothesized that conservative treatment for calcific tendinitis of the shoulder would produce good clinical results in most patients and that the initial radiologic appearance of calcific deposits would not affect the final results. Materials and methods: The study enrolled 87 consecutive patients (92 shoulders) who were diagnosed with calcific tendinitis and underwent conservative treatment. The mean age at the time of first visit was 53.2 years. The mean follow-up period was 16.1 months. Results: At the final follow-up, the Constant score increased to 83.64 points from a mean of 76.17 points at initial visit (P < .001). The score on the University of California, Los Angeles (UCLA) Shoulder Rating Scale improved from 23.42 to 29.69 points (P < .001), and there were 7 excellent (8%), 59 good (64%), and 26 poor (28%) results. Eleven shoulders (12%) revealed complete resolution of calcific deposits; 46 (50%) decreased in size; 18 (20%) had no change in size; and 17 (18%) increased in size. Discussion: Most patients in calcific tendinitis require treatment due to very severe shoulder pain, and conservative treatment may take precedence over operative treatment. Radiologic changes of calcific deposits report varying results depending on treatment methods. This study suggested that good radiologic results may be expected without performing special therapies. Conclusion: Conservative treatment for calcific tendinitis of the shoulder showed clinically significant improvement, with 72% of excellent or good results regardless of the location, radiologic type and size, and initial symptoms of calcific deposits. By radiologic type, 46% of the calcific deposits had a tendency to become more cloudy and inhomogeneous than initial findings, and 62% presented complete resolution or decrease in the size. Level of evidence: Level II, Retrospective Study, Prognostic Study. Ó 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Keywords: Shoulder; calcific tendinitis, conservative, radiologic
*Reprint requests: Yong Girl Rhee, MD, Department of Orthopaedic Surgery, Kyung Hee University School of Medicine, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-702, Korea. E-mail address: [email protected] (Y.G. Rhee).
Calcific tendinitis is a common rotator cuff disorder that causes severe pain in the shoulder. Although the prevalence of calcific tendinitis is high, its etiology and pathogenesis have remained unclear. Calcific tendinitis is observed most frequently in the tendon of the supraspinatus, but is also
1058-2746/2010/$36.00 - see front matter Ó 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. doi:10.1016/j.jse.2009.07.008
268 reported in the infraspinatus and subscapularis.6,13,26 The inflammatory reaction to a calcific deposit formed inside or around the rotator cuff is known to cause acute or chronic pain. Calcific tendinitis often heals spontaneously or is treated by conservative methods with good results.6,19,20,28 In some patients, calcific deposit removal is through open16,30 or arthroscopic1,7 procedures, with varying results. Most recently, the result of extracorporeal shock-wave therapy (ESWT)14,15,24 has been reported, but it still requires a longer-term follow up. Although conservative treatment is the first option for calcific tendinitis,12,20,28 only a few studies have followed its clinical results and have not documented over time the radiologic changes or the extent of resolution of a calcific deposit. The purpose of our study was to report the clinical results of conservative treatment in calcific tendinitis of the shoulder and to clarify the radiologic changes and natural course of calcific deposits. We hypothesized that conservative treatment for calcific tendinitis of the shoulder would produce good clinical results in most patients and that the initial radiologic appearance of calcific deposits would not affect the final results.
Materials and methods No Ethical or Investigational Review Board approval was obtained for this study because this study was retrospective in nature.
Patient selection The study enrolled 87 consecutive patients (92 shoulders) who had been treated for calcific tendinitis by conservative methods and followed up at our clinic between June 1997 and July 2005. Each patient had simple radiographs and medical records and was monitored for more than 1 year. There were 18 men (20%) and 74 women (80%). The mean age at the time of first visit was 53.2 years (range, 26-78 years). The right shoulder was involved in 72 and the left in 20. The dominant shoulder was involved in 81 and the nondominant in 11. Mean follow-up was 16.1 months (range, 12-42 months). For conservative treatment, nonsteroidal anti-inflammatory drugs (NSAIDs) were administered and passive shoulder stretching exercises were performed. Patients mainly performed home rehabilitation self-exercises. From the initial visit, the patients started passive range of motion (ROM) exercises, including pendulum exercises, passive forward flexion, external rotation, cross-body adduction, and internal rotation to the back. They performed passive ROM exercises in a tolerable range at first and were instructed to do the exercises 3 times a day, 10 rounds each time, until passive motion had been completely recovered.
Clinical and radiologic evaluations Subjective pain at rest and during active shoulder motions was measured with the visual analog scale (VAS), with 0 indicating no pain and 10 indicating extremely severe pain. Active shoulder motions,
N.S. Cho et al. including forward flexion, external rotation at the side, internal rotation to the back, and abduction were measured with the patient in the seated position at the initial visit and at the final follow-up. Each measurement was repeated 2 times by the first author (N.S.C.), and the average value of measurements was recorded. The Constant score5 and the University of California at Los Angeles (UCLA) Shoulder Rating Scale8 were used for clinical assessment. At the final follow-up, patients were asked to evaluate their subjective satisfaction with the treatment on a 100-point scale, with 100 indicating full satisfaction. On day 0 and at follow-up, standardized anteroposterior (AP) radiographs were taken in neutral, internal, and external rotation, together with axillary and supraspinatus-outlet views to determine the size, morphology, and location of the calcific deposits. Exposure parameters were kept constant for all radiographs, as follows: tube voltage of 63e68 kVp, 16e20 mAs, and focus-film distance of 100 cm. From the center of a calcific deposit, the long and the short axis were measured. The size of a calcific deposit was defined by multiplying the long axis by the short axis. Each measurement was repeated 3 times by first author, and the average value of measurements was recorded. According to the classification of Gartner and Simons on radiographs,10 the calcific deposits were classified into type I (sharply outlined and densely structured), type II (sharply outlined and inhomogeneous or homogenous with no defined border), and type III (cloudy and transparent in structure). During the follow-up, the changes in radiologic aspects of the calcifications, including type, size, and location, were determined using a standardized method.
Statistical analysis The Wilcoxon signed rank test was performed to assess the difference in results at the initial visit and at the final follow-up. The Mann-Whitney U test was used to compare the results between the groups. SPSS 12.0 software (SPSS, Chicago, IL) was used for all statistical analyses, with the a level set at 0.05.
Results Pain The VAS score for pain at rest decreased from a mean of 1.69 (range, 0e4) at the first visit to 0.81 (range, 0e3) at the final follow-up. The VAS for pain during motion reduced remarkably to 2.69 (range, 0e5) from the mean of 6.36 (range, 3e10) at the initial visit. The improvement of pain at rest (P < .001) and during motion (P < .001) was statistically significant.
Range of motion The mean active ROM at the initial visit was 151.9 (range, 100 e175 ) of forward flexion, 43.5 (range 5 e80 ) of external rotation, T10 (range, T4eL5) of internal rotation, and 156.4 (range 30 e180 ) of abduction. At the final follow-up, the mean ROM improved to 169.4 (range 130 e180 ), 57.4 (range 30 e80 ), T7 (range T4eL4), and 162.3 (range 85 e180 ), respectively. The
Radiologic course in calcific tendinitis Table I
269
Change of radiologic type of calcific deposit
Table II
Change of size of calcific deposit
Initial type, No. (%)
Initial size, No. (%)
Last type)
No.
I (n ¼ 46)
II (n ¼ 35)
III (n ¼ 11)
I II III
26 26 40
20 (43) 11 (24) 15 (33)
6 (17) 13 (37) 16 (46)
0 (0) 2 (18) 9 (82)
)According
to the classification of Gartner and Simons on radiographs,10 the calcific deposits were classified into type I (sharply outlined and densely structured), type II (sharply outlined and inhomogeneous or homogenous with no defined border), and type III (cloudy and transparent in structure).
improvement at the final follow-up was statistically significant for forward flexion (P ¼ .003), external rotation (P ¼ .087), internal rotation (P ¼ .017), and abduction (P ¼ .058).
Clinical assessment The Constant score at the final follow-up increased to 83.64 points (range, 67e91 points) from the mean of 76.17 points (range, 57-89 points) at the initial visit (P < .001). The UCLA score improved from 23.42 points (range, 18e28 points) to 29.69 points (range, 20e33 points; P < .001), and there were 7 excellent (8%), 59 good (64%), and 26 poor (28%) results. At the final follow-up, the mean subjective score of patient satisfaction was 81 points (range, 55e100 points).
Radiologic results On day 0, calcific deposits were located in the tendon of the supraspinatus in 70 shoulders (76%), the infraspinatus in 15 (16%), and the subscapularis in 7 (8%). By radiologic classification, 46 were type I, 35 were type II, and 11 were type III. At the final follow-up, 26 shoulders were type I, 26 were type II, and 40 were type III (Table I). At the final follow-up of the 46 shoulders that were type I on day 0, 20 (43%) remained type I, 11 (24%) became type II, and 15 (33%) became type II. The 35 shoulders that were type II were transformed into 13 (37%) type II, 6 (17%) type I, and 16 (46%) type III. Of the 11 type III shoulders, only 2 (18%) were changed to type II, and the other 9 (82%) remained as type III. On radiologic observation, types I and II gradually were changed to types II and III with time. Overall, 42 of the total shoulders (46%) showed a more cloudy and inhomogeneous calcific deposit than what was observed from initial radiographs. The mean size of calcific deposits on day 0 was 106 mm2 (range, 10e560 mm2). Deposits were sized smaller than 50 mm2 in 28 shoulders (30%), between 51 and 100 mm2 in 52 (57%), and larger than 101 mm2 in 12 (13%). At the final follow-up, 50 shoulders (54%) had a deposit sized smaller than 50 mm2; 29 (32%) were
50 mm2 51-100 mm2 101 mm2 Last size
No. (n ¼ 28)
(n ¼ 52)
(n ¼ 12)
Complete resolution Decrease in size No change in size Increase in size
11 46 18 17
5 28 7 12
0 7 3 2
6 11 8 3
(21) (39) (29) (11)
(10) (54) (13) (23)
(0) (58) (25) (17)
between 51 mm2 and 100 mm2; and 13 (14%) were larger than 101 mm2. Eleven shoulders (12%) revealed complete resolution of calcific deposits, 46 (50%) had decreased in size, 18 (20%) had no change in size, and 17 (18%) increased in size (Table II).
Comparison by location of calcific deposits Regardless of the location of calcific deposits, all patients reported improvements at the final follow-up in the VAS score at rest and during motion, ROM, Constant score, and UCLA score (Table III). In the patients with a calcific deposit located in the supraspinatus tendon, the Constant score increased from 78.33 on day 0 to 84.11 at the final follow-up (P ¼ .041). The UCLA score also improved from 23.89 to 29.3 (P ¼ .013). In the patients with a calcific deposit in the infraspinatus tendon, the Constant score rose from 68.67 to 80.67 (P ¼ .004) and the UCLA score from 22 to 31.5 (P ¼ .002). In the patients with a deposit in the subscapularis tendon, the Constant score improved from 71.67 to 85.33 (P ¼ 0.035) and the UCLA score from 22 to 29.67 (P ¼ .026). For statistical analysis, we divided the patients into a first group with a calcific deposit located in the supraspinatus tendon (70 shoulders) and a second group with a calcific deposit in the infraspinatus or subscapularis tendon (22 shoulders). At the final follow-up, the supraspinatus tendon group showed a significantly lower increase in the Constant score than the other group (P ¼ .016). However, there was no statistically significant difference in the UCLA score between the 2 groups (P ¼ .067).
Comparison by initial radiologic classification All the shoulders, regardless of the initial radiologic classification of a calcific deposit, showed improvements at the final follow-up in VAS at rest and during motion, ROM, Constant score, and UCLA score (Table IV). For statistical analysis, the shoulders were divided into a group with a well-defined homogeneous deposit (type I; n ¼ 46) and the other group with a poorly defined inhomogeneous deposit (type II and III; n ¼ 46). The two groups presented no statistically significant difference in Constant (P ¼ .111) and UCLA scores (P ¼ .118).
270
N.S. Cho et al.
Table III
Comparison by location of calcific deposit Supraspinatus (n ¼ 70)
Infraspinatus (n ¼ 15)
Subscapularis (n ¼ 7)
Score
Initial
Last
Initial
Last
Initial
Last
Constant UCLA
78.33 23.89
84.11 29.30
68.67 22.00
80.67 31.50
71.67 22.00
85.33 29.67
UCLA, University of California, Los Angeles.
Table IV deposit)
Comparison by initial radiologic type of calcific I (n ¼ 46)
II (n ¼ 35)
III (n ¼ 11)
Score
Initial
Last
Initial
Last
Initial
Last
Constant UCLA
73.78 22.39
82.44 29.89
78.29 24.29
84.43 29.43
79.50 25.00
86.25 29.75
UCLA, University of California, Los Angeles. )According to the classification of Gartner and Simons on radiographs,10 the calcific deposits were classified into type I (sharply outlined and densely structured), type II (sharply outlined and inhomogenous or homogenous with no defined border), and type III (cloudy and transparent in structure).
Comparison by size of calcific deposits At the final follow-up, all shoulders improved, regardless of the size of a calcific deposit in every evaluation performed (Table V). There was no statistically significant difference in the Constant score and the UCLA score between the 28 shoulders in the first group with a calcific deposit sized smaller than 50 mm2 (P ¼ .520) and the 64 shoulders in the second group with a deposit larger than 51 mm2 (P ¼ .612).
Comparison by extent of initial symptoms According to the pain measured during motion on day 0, the shoulders were divided into a group that had a VAS score of 7 or higher (n ¼ 48) and a second group with a VAS score of 6 or lower (n ¼ 44). Both groups presented improvements at the final follow-up in every evaluation, but there was no statistically significant difference between the 2 groups in Constant (P ¼ .661) and UCLA scores (P ¼ .950).
Discussion Calcific tendinitis is most commonly observed in the shoulder joint, particularly in the tendon of supraspinatus. Plenk19 reported that 82% of calcific deposits studied were located in the supraspinatus, and Bosworth3 suggested the incidence at supraspinatus and infraspinatus tendons combined to be 90%. Particularly in the tendon of supraspinatus, a calcific deposit develops in the area 1.5 to
2.0 cm away from the greater tuberosity of the humerus. This area is known as the ‘‘zone of stress’’ because it shows poor vascularity hemodynamically.2,11,25,30 In addition, calcific deposits are mostly bilateral and affect women more often than men.6,13 In our previous study on arthroscopic procedures for the treatment of calcific tendinitis,21 we reported 66% of calcific deposits in the supraspinatus, 17% in the infraspinatus, and 17% in the subscapularis. In the present study of conservative treatment, 76% of the deposits were located in the supraspinatus tendon, indicating similar results with previous reports. By sex, the incidence was much higher in women (80%) than in men (20%). The mechanism of calcific tendinitis has been unclear. The most widely accepted view is the reduction of regional oxygen tension and the resulting hypoxia, which transforms tenocytes into chondrocytes and increases intratendinous pressure, causing a calcific deposit.4,32 In 1990 Uhthoff et al31 described that the calcific deposit formed inside the tendon and reabsorbed through spontaneous phagocytosis led to severe pain. In 1997 Uhthoff et al30 explained the progression of calcific tendinitis in 3 phases: precalcific, calcific, and postcalcific stages. The calcific stage is subdivided into formative, resting, and resorption stages. The resorption stage is where phagocytic resorption takes place and the rotator cuff presents severe hyperemia, causing acute or hyper acute pain. This is the general progression of the patient with calcific tendinitis. Radiologic changes of calcific deposits report varying results depending on treatment methods. Needle aspiration and lavage performed under ultrasound or fluoroscopy has shown rates of elimination between 28% and 76%.9,10,17,18 In cases of ESWT, the elimination rate was also wide, with 15% to 70%, even though the rate of disintegration and resorption increased with higher levels of shock waves and longer periods of follow-up.14,22-24,29,33 On the other hand, in our previous study on arthroscopic treatment of calcific tendinitis, the deposits were completely removed in 72% of the shoulders studied.21 In the present study, we observed that type I and type II deposits by the classification of Gartner and Simons changed to type II and type III over time in most of the shoulders. Overall, the calcific deposits became more cloudy and inhomogeneous in 46% (42 shoulders); in addition, calcific deposits were completely removed in 12% and removed or reduced in size in 62%. Although the removal rate of calcific deposits was lower than that of
Radiologic course in calcific tendinitis Table V
271
Comparison by initial size of calcific deposit 50 mm2 (n ¼ 28)
51-100 mm2 (n ¼ 52)
101 mm2 (n ¼ 12)
Score
Initial
Last
Initial
Last
Initial
Last
Constant UCLA
76.82 23.64
85.82 30.73
76.65 23.60
82.10 29.30
72.80 22.20
85.00 29.00
UCLA, University of California, Los Angeles.
other therapies, the deposits decreased in size in more than 60% of the total shoulders in our study. This result suggested that good radiologic results may be expected without performing special therapies. Many authors have already stated the irrelevance of the size of a calcific deposit to the severity of symptoms.6,13 A very small-sized deposit can cause severe pain, whereas a large-sized deposit only results in slight symptoms. Our study also confirmed that the size of a calcific deposit and its radiologic change did not have significant correlations to clinical results. Thus, even if conservative treatment for calcific tendinitis showed a relatively low removal rate of calcific deposits, it can still be the primary treatment method for calcific tendinitis because radiologic results do not have direct correlations to clinical results. Bosworth3 and Rupp et al27 reported that spontaneous healing occurred in 6.4% to 32.0% of patients with calcific tendinitis. Most patients require treatment due to very severe shoulder pain, however; and conservative treatment may take precedence over operative treatment. NSAIDs therapy has been the main conservative method. Other methods include steroid injection, mild shoulder passive stretching exercises, ESWT,14,15,24 and needle aspiration and lavage. We applied various conservative methods suitable to each patient. For those who complained of severe pain despite the treatment, limited arthroscopic or open procedures were performed. Because conservative treatments in our study showed good results regardless of the location, radiologic type and size, and initial symptoms of calcific deposits, one needs to make a careful decision when other therapies and operative treatments are being considered. A weakness of our study was that although we used a standardized method for radiologic analysis, a subtle difference in magnifications might be applied to each radiograph that was taken, and the shape of the deposit was usually irregular. This may have caused errors in measuring the size of calcific deposits. The best way is to measure the area by digitizing the radiographs. In reality, however, it is almost impossible to precisely measure the actual size of a calcific deposit. Thus, in an effort to minimize such measuring errors on the radiographs, the same author repeated each measurement 3 times and the average value of measurements was recorded. In addition, being retrospective in nature, our study has limitations similar to other retrospective studies. Finally, only those patients whose simple radiographs were monitored for more than 1 year were enrolled for this
study. Because several patients without more than a year of radiographic follow-up were excluded, only 87 patients (92 shoulders) of those who had had conservative treatment became final study cohort. However, these patients were randomly selected from a consecutive series and thus were considered consecutive, which prevented the patient selection bias. In conclusion, conservative treatment in calcific tendinitis of the shoulder showed clinically significant improvement, with 72% of excellent or good results. The location of the calcific deposits, initial radiologic type and size, and the extent of initial symptom did not affect the clinical results. In the radiologic type, 46% had a tendency to become more cloudy and inhomogeneous than initial findings, and 62% revealed complete resolution or a decrease in the size of deposits. Because conservative treatment showed good results in most patients, it can be considered as the primary treatment method for calcific tendinitis.
Disclaimer The authors of this article, their immediate families, and any research foundation with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.
References 1. Ark JW, Flock TJ, Flatow EL, Bigliani LU. Arthroscopic treatment of calcific tendonitis of the shoulder. Arthroscopy 1992;8:183-8. 2. Bateman JE. The neck and shoulder. Philadelphia, PA: WB Saunders; 1978. 3. Bosworth DM. Calcium deposits in the shoulder and subacromial bursitis: a survey of 12,122 shoulders. JAMA 1941;116:2477-82. 4. Codman EA. The shoulder: rupture of the supraspinatus tendon and other lesions in or about the subacromial bursa. Boston, MA: Thomas Todd; 1934. 5. Constant CR, Murley AH. A clinical method of functional assessment of the shoulder. Clin Orthop Relat Res 1987;214:160-4. 6. DePalma AF, Kruper JS. Long term study of shoulder joints afflicted with and treated for calcific tendinitis. Clin Orthop Relat Res 1961;20: 61-72. 7. Ellman H. Arthroscopic subacromial decompression: analysis of one to three year results. Arthroscopy 1987;3:173-81. 8. Ellman H, Hanker G, Bayer M. Repair of the rotator cuff: end-result study of factors influencing reconstruction. J Bone Joint Surg Am 1986;68:1136-44.
272 9. Farin PU, Rasanen H, Jaroma H, Harju A. Rotator cuff calcifications: treatment with ultrasound-guided percutaneous needle aspiration and lavage. Skeletal Radiol 1996;25:551-4. 10. Gartner J, Simons B. Analysis of calcific deposits in calcifying tendinitis. Clin Orthop Relat Res 1990;254:111-20. 11. Hurt G, Baker CL Jr. Calcific tendinitis of the shoulder. Orthop Clin North Am 2003;34:567-75. 12. Jerosch J, Strauss JM, Schmiel S. Arthroscopic treatment of calcific tendinitis of the shoulder. J Shoulder Elbow Surg 1998;7:30-7. 13. Lippmann RK. Observations concerning the calcific cuff deposit. Clin Orthop Relat Res 1961;20:49-60. 14. Loew M, Daecke W, Kusnierczak D, Rahmanzadeh M. Shock wave therapy is effective for chronic calcifying tendonitis of the shoulder. J Bone Joint Surg Br 1999;81:863-7. 15. Loew M, Jurgowski W, Mau HC, Thomsen M. Treatment of calcifying tendinitis of rotator cuff by extracorporeal shock waves: a preliminary report. J Shoulder Elbow Surg 1995;4:101-6. 16. McLaughlin HL. The selection of calcium deposit for operation: the technique and results of operation. Surg Clin North Am 1963;43:1501-4. 17. Noel E, Carrillon Y, Gaillard T, Bouvier M. Needle aspiration irrigation in calcifying tendonitis of the cuff. In: Gazielly DF, Gleyze P, Thomas T, editors. The cuff. Paris: Elsevier; 1997. p. 152-7. 18. Pfister J, Gerber H. Chronic calcifying tendonitis of the shoulder: therapy by percutaneous needle aspiration and lavage: a prospective open study of 62 shoulders. Clin Rheumatol 1997;16:269-74. 19. Plenk HP. Calcifying tendinitis of the shoulder. Radiology 1952;59: 384-9. 20. Re LP, Karzel RP. Management of rotator cuff calcifications. Orthop Clin North Am 1993;24:125-32. 21. Rhee YG, Kim YH, Park MS. Arthroscopic treatment in calcific tendinitis of the shoulder. J Korean Shoulder Elbow Soc 2000;3:68-74.
N.S. Cho et al. 22. Rompe JD, Burger R, Hopf C, Eysel P. Shoulder function after extracorporeal shock wave therapy for calcific tendonitis. J Shoulder Elbow Surg 1998;7:505-9. 23. Rompe JD, Rumler F, Hopf C, Nafe B, Heine H. Extracorporeal shock wave therapy for calcifying tendinosis of the shoulder. Clin Orthop Relat Res 1995;321:196-201. 24. Rompe JD, Zoellner JZ, Nafe B. Shock wave therapy versus conventional surgery in treatment of the calcifying tendonitis of the shoulder. Clin Orthop Relat Res 2001;387:72-82. 25. Rothman RH, Parke WW. The vascular anatomy of the rotator cuff. Clin Orthop Relat Res 1965;41:176-86. 26. Rowe CR. Calcific tendinitis. Instr Course Lect 1985;34:196-8. 27. Rupp S, Seil R, Kohn D. Tendinosis calcarea of the rotator cuff. Orthopade 2000;29:852-67. 28. Sabeti-Aschraf M, Dorotka R, Goll A, Trieb K. Extracorporeal shock wave therapy in the treatment of calcific tendinitis of the rotator cuff. Am J Sports Med 2005;33:1365-8. 29. Seil R, Rupp S, Hammer DS, Ensslin S, Gebhardt T, Kohn D. Extracorporeal shock wave therapy in tendinosis calcarea of the rotator cuff: comparison of different treatment protocols. Z Orthop Ihre Grenzgeb 1999;137:310-5. 30. Uhthoff HK, Loehr JW. Calcific tendinopathy of the rotator cuff: pathogenesis, diagnosis and management. J Am Acad Orthop Surg 1997;5:183-91. 31. Uhthoff HK, Sarkar K. Calcifying tendinitis. In: Rockwood CA Jr, Matsen FA 3rd, editors. The shoulder. Philadelphia, PA: WB Saunders; 1990. p. 774-90. 32. Uhthoff HK, Sarkar K, Maynard JA. Calcifying tendinitis: a new concept of its pathogenesis. Clin Orthop Relat Res 1976;118:164-8. 33. Wang CJ, Ko JY, Chen HS. Treatment of calcifying tendonitis of the shoulder with shock wave therapy. Clin Orthop Relat Res 2001;387:83-9.
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Radiologic course of the calcific deposits in calcific tendinitis of the shoulder: Does the initial radiologic aspect affect the final results? Nam Su Cho, MD, Bong Gun Lee, MD, Yong Girl Rhee, MD* Shoulder & Elbow Clinic, Department of Orthopaedic Surgery, Kyung Hee University School of Medicine, Seoul, Korea Hypothesis: Although conservative treatment is the first option for the treatment of calcific tendinitis, only a few reports have described its results, without documenting the radiologic changes over time of calcific deposits. We hypothesized that conservative treatment for calcific tendinitis of the shoulder would produce good clinical results in most patients and that the initial radiologic appearance of calcific deposits would not affect the final results. Materials and methods: The study enrolled 87 consecutive patients (92 shoulders) who were diagnosed with calcific tendinitis and underwent conservative treatment. The mean age at the time of first visit was 53.2 years. The mean follow-up period was 16.1 months. Results: At the final follow-up, the Constant score increased to 83.64 points from a mean of 76.17 points at initial visit (P < .001). The score on the University of California, Los Angeles (UCLA) Shoulder Rating Scale improved from 23.42 to 29.69 points (P < .001), and there were 7 excellent (8%), 59 good (64%), and 26 poor (28%) results. Eleven shoulders (12%) revealed complete resolution of calcific deposits; 46 (50%) decreased in size; 18 (20%) had no change in size; and 17 (18%) increased in size. Discussion: Most patients in calcific tendinitis require treatment due to very severe shoulder pain, and conservative treatment may take precedence over operative treatment. Radiologic changes of calcific deposits report varying results depending on treatment methods. This study suggested that good radiologic results may be expected without performing special therapies. Conclusion: Conservative treatment for calcific tendinitis of the shoulder showed clinically significant improvement, with 72% of excellent or good results regardless of the location, radiologic type and size, and initial symptoms of calcific deposits. By radiologic type, 46% of the calcific deposits had a tendency to become more cloudy and inhomogeneous than initial findings, and 62% presented complete resolution or decrease in the size. Level of evidence: Level II, Retrospective Study, Prognostic Study. Ó 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Keywords: Shoulder; calcific tendinitis, conservative, radiologic
*Reprint requests: Yong Girl Rhee, MD, Department of Orthopaedic Surgery, Kyung Hee University School of Medicine, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-702, Korea. E-mail address: [email protected] (Y.G. Rhee).
Calcific tendinitis is a common rotator cuff disorder that causes severe pain in the shoulder. Although the prevalence of calcific tendinitis is high, its etiology and pathogenesis have remained unclear. Calcific tendinitis is observed most frequently in the tendon of the supraspinatus, but is also
1058-2746/2010/$36.00 - see front matter Ó 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. doi:10.1016/j.jse.2009.07.008
268 reported in the infraspinatus and subscapularis.6,13,26 The inflammatory reaction to a calcific deposit formed inside or around the rotator cuff is known to cause acute or chronic pain. Calcific tendinitis often heals spontaneously or is treated by conservative methods with good results.6,19,20,28 In some patients, calcific deposit removal is through open16,30 or arthroscopic1,7 procedures, with varying results. Most recently, the result of extracorporeal shock-wave therapy (ESWT)14,15,24 has been reported, but it still requires a longer-term follow up. Although conservative treatment is the first option for calcific tendinitis,12,20,28 only a few studies have followed its clinical results and have not documented over time the radiologic changes or the extent of resolution of a calcific deposit. The purpose of our study was to report the clinical results of conservative treatment in calcific tendinitis of the shoulder and to clarify the radiologic changes and natural course of calcific deposits. We hypothesized that conservative treatment for calcific tendinitis of the shoulder would produce good clinical results in most patients and that the initial radiologic appearance of calcific deposits would not affect the final results.
Materials and methods No Ethical or Investigational Review Board approval was obtained for this study because this study was retrospective in nature.
Patient selection The study enrolled 87 consecutive patients (92 shoulders) who had been treated for calcific tendinitis by conservative methods and followed up at our clinic between June 1997 and July 2005. Each patient had simple radiographs and medical records and was monitored for more than 1 year. There were 18 men (20%) and 74 women (80%). The mean age at the time of first visit was 53.2 years (range, 26-78 years). The right shoulder was involved in 72 and the left in 20. The dominant shoulder was involved in 81 and the nondominant in 11. Mean follow-up was 16.1 months (range, 12-42 months). For conservative treatment, nonsteroidal anti-inflammatory drugs (NSAIDs) were administered and passive shoulder stretching exercises were performed. Patients mainly performed home rehabilitation self-exercises. From the initial visit, the patients started passive range of motion (ROM) exercises, including pendulum exercises, passive forward flexion, external rotation, cross-body adduction, and internal rotation to the back. They performed passive ROM exercises in a tolerable range at first and were instructed to do the exercises 3 times a day, 10 rounds each time, until passive motion had been completely recovered.
Clinical and radiologic evaluations Subjective pain at rest and during active shoulder motions was measured with the visual analog scale (VAS), with 0 indicating no pain and 10 indicating extremely severe pain. Active shoulder motions,
N.S. Cho et al. including forward flexion, external rotation at the side, internal rotation to the back, and abduction were measured with the patient in the seated position at the initial visit and at the final follow-up. Each measurement was repeated 2 times by the first author (N.S.C.), and the average value of measurements was recorded. The Constant score5 and the University of California at Los Angeles (UCLA) Shoulder Rating Scale8 were used for clinical assessment. At the final follow-up, patients were asked to evaluate their subjective satisfaction with the treatment on a 100-point scale, with 100 indicating full satisfaction. On day 0 and at follow-up, standardized anteroposterior (AP) radiographs were taken in neutral, internal, and external rotation, together with axillary and supraspinatus-outlet views to determine the size, morphology, and location of the calcific deposits. Exposure parameters were kept constant for all radiographs, as follows: tube voltage of 63e68 kVp, 16e20 mAs, and focus-film distance of 100 cm. From the center of a calcific deposit, the long and the short axis were measured. The size of a calcific deposit was defined by multiplying the long axis by the short axis. Each measurement was repeated 3 times by first author, and the average value of measurements was recorded. According to the classification of Gartner and Simons on radiographs,10 the calcific deposits were classified into type I (sharply outlined and densely structured), type II (sharply outlined and inhomogeneous or homogenous with no defined border), and type III (cloudy and transparent in structure). During the follow-up, the changes in radiologic aspects of the calcifications, including type, size, and location, were determined using a standardized method.
Statistical analysis The Wilcoxon signed rank test was performed to assess the difference in results at the initial visit and at the final follow-up. The Mann-Whitney U test was used to compare the results between the groups. SPSS 12.0 software (SPSS, Chicago, IL) was used for all statistical analyses, with the a level set at 0.05.
Results Pain The VAS score for pain at rest decreased from a mean of 1.69 (range, 0e4) at the first visit to 0.81 (range, 0e3) at the final follow-up. The VAS for pain during motion reduced remarkably to 2.69 (range, 0e5) from the mean of 6.36 (range, 3e10) at the initial visit. The improvement of pain at rest (P < .001) and during motion (P < .001) was statistically significant.
Range of motion The mean active ROM at the initial visit was 151.9 (range, 100 e175 ) of forward flexion, 43.5 (range 5 e80 ) of external rotation, T10 (range, T4eL5) of internal rotation, and 156.4 (range 30 e180 ) of abduction. At the final follow-up, the mean ROM improved to 169.4 (range 130 e180 ), 57.4 (range 30 e80 ), T7 (range T4eL4), and 162.3 (range 85 e180 ), respectively. The
Radiologic course in calcific tendinitis Table I
269
Change of radiologic type of calcific deposit
Table II
Change of size of calcific deposit
Initial type, No. (%)
Initial size, No. (%)
Last type)
No.
I (n ¼ 46)
II (n ¼ 35)
III (n ¼ 11)
I II III
26 26 40
20 (43) 11 (24) 15 (33)
6 (17) 13 (37) 16 (46)
0 (0) 2 (18) 9 (82)
)According
to the classification of Gartner and Simons on radiographs,10 the calcific deposits were classified into type I (sharply outlined and densely structured), type II (sharply outlined and inhomogeneous or homogenous with no defined border), and type III (cloudy and transparent in structure).
improvement at the final follow-up was statistically significant for forward flexion (P ¼ .003), external rotation (P ¼ .087), internal rotation (P ¼ .017), and abduction (P ¼ .058).
Clinical assessment The Constant score at the final follow-up increased to 83.64 points (range, 67e91 points) from the mean of 76.17 points (range, 57-89 points) at the initial visit (P < .001). The UCLA score improved from 23.42 points (range, 18e28 points) to 29.69 points (range, 20e33 points; P < .001), and there were 7 excellent (8%), 59 good (64%), and 26 poor (28%) results. At the final follow-up, the mean subjective score of patient satisfaction was 81 points (range, 55e100 points).
Radiologic results On day 0, calcific deposits were located in the tendon of the supraspinatus in 70 shoulders (76%), the infraspinatus in 15 (16%), and the subscapularis in 7 (8%). By radiologic classification, 46 were type I, 35 were type II, and 11 were type III. At the final follow-up, 26 shoulders were type I, 26 were type II, and 40 were type III (Table I). At the final follow-up of the 46 shoulders that were type I on day 0, 20 (43%) remained type I, 11 (24%) became type II, and 15 (33%) became type II. The 35 shoulders that were type II were transformed into 13 (37%) type II, 6 (17%) type I, and 16 (46%) type III. Of the 11 type III shoulders, only 2 (18%) were changed to type II, and the other 9 (82%) remained as type III. On radiologic observation, types I and II gradually were changed to types II and III with time. Overall, 42 of the total shoulders (46%) showed a more cloudy and inhomogeneous calcific deposit than what was observed from initial radiographs. The mean size of calcific deposits on day 0 was 106 mm2 (range, 10e560 mm2). Deposits were sized smaller than 50 mm2 in 28 shoulders (30%), between 51 and 100 mm2 in 52 (57%), and larger than 101 mm2 in 12 (13%). At the final follow-up, 50 shoulders (54%) had a deposit sized smaller than 50 mm2; 29 (32%) were
50 mm2 51-100 mm2 101 mm2 Last size
No. (n ¼ 28)
(n ¼ 52)
(n ¼ 12)
Complete resolution Decrease in size No change in size Increase in size
11 46 18 17
5 28 7 12
0 7 3 2
6 11 8 3
(21) (39) (29) (11)
(10) (54) (13) (23)
(0) (58) (25) (17)
between 51 mm2 and 100 mm2; and 13 (14%) were larger than 101 mm2. Eleven shoulders (12%) revealed complete resolution of calcific deposits, 46 (50%) had decreased in size, 18 (20%) had no change in size, and 17 (18%) increased in size (Table II).
Comparison by location of calcific deposits Regardless of the location of calcific deposits, all patients reported improvements at the final follow-up in the VAS score at rest and during motion, ROM, Constant score, and UCLA score (Table III). In the patients with a calcific deposit located in the supraspinatus tendon, the Constant score increased from 78.33 on day 0 to 84.11 at the final follow-up (P ¼ .041). The UCLA score also improved from 23.89 to 29.3 (P ¼ .013). In the patients with a calcific deposit in the infraspinatus tendon, the Constant score rose from 68.67 to 80.67 (P ¼ .004) and the UCLA score from 22 to 31.5 (P ¼ .002). In the patients with a deposit in the subscapularis tendon, the Constant score improved from 71.67 to 85.33 (P ¼ 0.035) and the UCLA score from 22 to 29.67 (P ¼ .026). For statistical analysis, we divided the patients into a first group with a calcific deposit located in the supraspinatus tendon (70 shoulders) and a second group with a calcific deposit in the infraspinatus or subscapularis tendon (22 shoulders). At the final follow-up, the supraspinatus tendon group showed a significantly lower increase in the Constant score than the other group (P ¼ .016). However, there was no statistically significant difference in the UCLA score between the 2 groups (P ¼ .067).
Comparison by initial radiologic classification All the shoulders, regardless of the initial radiologic classification of a calcific deposit, showed improvements at the final follow-up in VAS at rest and during motion, ROM, Constant score, and UCLA score (Table IV). For statistical analysis, the shoulders were divided into a group with a well-defined homogeneous deposit (type I; n ¼ 46) and the other group with a poorly defined inhomogeneous deposit (type II and III; n ¼ 46). The two groups presented no statistically significant difference in Constant (P ¼ .111) and UCLA scores (P ¼ .118).
270
N.S. Cho et al.
Table III
Comparison by location of calcific deposit Supraspinatus (n ¼ 70)
Infraspinatus (n ¼ 15)
Subscapularis (n ¼ 7)
Score
Initial
Last
Initial
Last
Initial
Last
Constant UCLA
78.33 23.89
84.11 29.30
68.67 22.00
80.67 31.50
71.67 22.00
85.33 29.67
UCLA, University of California, Los Angeles.
Table IV deposit)
Comparison by initial radiologic type of calcific I (n ¼ 46)
II (n ¼ 35)
III (n ¼ 11)
Score
Initial
Last
Initial
Last
Initial
Last
Constant UCLA
73.78 22.39
82.44 29.89
78.29 24.29
84.43 29.43
79.50 25.00
86.25 29.75
UCLA, University of California, Los Angeles. )According to the classification of Gartner and Simons on radiographs,10 the calcific deposits were classified into type I (sharply outlined and densely structured), type II (sharply outlined and inhomogenous or homogenous with no defined border), and type III (cloudy and transparent in structure).
Comparison by size of calcific deposits At the final follow-up, all shoulders improved, regardless of the size of a calcific deposit in every evaluation performed (Table V). There was no statistically significant difference in the Constant score and the UCLA score between the 28 shoulders in the first group with a calcific deposit sized smaller than 50 mm2 (P ¼ .520) and the 64 shoulders in the second group with a deposit larger than 51 mm2 (P ¼ .612).
Comparison by extent of initial symptoms According to the pain measured during motion on day 0, the shoulders were divided into a group that had a VAS score of 7 or higher (n ¼ 48) and a second group with a VAS score of 6 or lower (n ¼ 44). Both groups presented improvements at the final follow-up in every evaluation, but there was no statistically significant difference between the 2 groups in Constant (P ¼ .661) and UCLA scores (P ¼ .950).
Discussion Calcific tendinitis is most commonly observed in the shoulder joint, particularly in the tendon of supraspinatus. Plenk19 reported that 82% of calcific deposits studied were located in the supraspinatus, and Bosworth3 suggested the incidence at supraspinatus and infraspinatus tendons combined to be 90%. Particularly in the tendon of supraspinatus, a calcific deposit develops in the area 1.5 to
2.0 cm away from the greater tuberosity of the humerus. This area is known as the ‘‘zone of stress’’ because it shows poor vascularity hemodynamically.2,11,25,30 In addition, calcific deposits are mostly bilateral and affect women more often than men.6,13 In our previous study on arthroscopic procedures for the treatment of calcific tendinitis,21 we reported 66% of calcific deposits in the supraspinatus, 17% in the infraspinatus, and 17% in the subscapularis. In the present study of conservative treatment, 76% of the deposits were located in the supraspinatus tendon, indicating similar results with previous reports. By sex, the incidence was much higher in women (80%) than in men (20%). The mechanism of calcific tendinitis has been unclear. The most widely accepted view is the reduction of regional oxygen tension and the resulting hypoxia, which transforms tenocytes into chondrocytes and increases intratendinous pressure, causing a calcific deposit.4,32 In 1990 Uhthoff et al31 described that the calcific deposit formed inside the tendon and reabsorbed through spontaneous phagocytosis led to severe pain. In 1997 Uhthoff et al30 explained the progression of calcific tendinitis in 3 phases: precalcific, calcific, and postcalcific stages. The calcific stage is subdivided into formative, resting, and resorption stages. The resorption stage is where phagocytic resorption takes place and the rotator cuff presents severe hyperemia, causing acute or hyper acute pain. This is the general progression of the patient with calcific tendinitis. Radiologic changes of calcific deposits report varying results depending on treatment methods. Needle aspiration and lavage performed under ultrasound or fluoroscopy has shown rates of elimination between 28% and 76%.9,10,17,18 In cases of ESWT, the elimination rate was also wide, with 15% to 70%, even though the rate of disintegration and resorption increased with higher levels of shock waves and longer periods of follow-up.14,22-24,29,33 On the other hand, in our previous study on arthroscopic treatment of calcific tendinitis, the deposits were completely removed in 72% of the shoulders studied.21 In the present study, we observed that type I and type II deposits by the classification of Gartner and Simons changed to type II and type III over time in most of the shoulders. Overall, the calcific deposits became more cloudy and inhomogeneous in 46% (42 shoulders); in addition, calcific deposits were completely removed in 12% and removed or reduced in size in 62%. Although the removal rate of calcific deposits was lower than that of
Radiologic course in calcific tendinitis Table V
271
Comparison by initial size of calcific deposit 50 mm2 (n ¼ 28)
51-100 mm2 (n ¼ 52)
101 mm2 (n ¼ 12)
Score
Initial
Last
Initial
Last
Initial
Last
Constant UCLA
76.82 23.64
85.82 30.73
76.65 23.60
82.10 29.30
72.80 22.20
85.00 29.00
UCLA, University of California, Los Angeles.
other therapies, the deposits decreased in size in more than 60% of the total shoulders in our study. This result suggested that good radiologic results may be expected without performing special therapies. Many authors have already stated the irrelevance of the size of a calcific deposit to the severity of symptoms.6,13 A very small-sized deposit can cause severe pain, whereas a large-sized deposit only results in slight symptoms. Our study also confirmed that the size of a calcific deposit and its radiologic change did not have significant correlations to clinical results. Thus, even if conservative treatment for calcific tendinitis showed a relatively low removal rate of calcific deposits, it can still be the primary treatment method for calcific tendinitis because radiologic results do not have direct correlations to clinical results. Bosworth3 and Rupp et al27 reported that spontaneous healing occurred in 6.4% to 32.0% of patients with calcific tendinitis. Most patients require treatment due to very severe shoulder pain, however; and conservative treatment may take precedence over operative treatment. NSAIDs therapy has been the main conservative method. Other methods include steroid injection, mild shoulder passive stretching exercises, ESWT,14,15,24 and needle aspiration and lavage. We applied various conservative methods suitable to each patient. For those who complained of severe pain despite the treatment, limited arthroscopic or open procedures were performed. Because conservative treatments in our study showed good results regardless of the location, radiologic type and size, and initial symptoms of calcific deposits, one needs to make a careful decision when other therapies and operative treatments are being considered. A weakness of our study was that although we used a standardized method for radiologic analysis, a subtle difference in magnifications might be applied to each radiograph that was taken, and the shape of the deposit was usually irregular. This may have caused errors in measuring the size of calcific deposits. The best way is to measure the area by digitizing the radiographs. In reality, however, it is almost impossible to precisely measure the actual size of a calcific deposit. Thus, in an effort to minimize such measuring errors on the radiographs, the same author repeated each measurement 3 times and the average value of measurements was recorded. In addition, being retrospective in nature, our study has limitations similar to other retrospective studies. Finally, only those patients whose simple radiographs were monitored for more than 1 year were enrolled for this
study. Because several patients without more than a year of radiographic follow-up were excluded, only 87 patients (92 shoulders) of those who had had conservative treatment became final study cohort. However, these patients were randomly selected from a consecutive series and thus were considered consecutive, which prevented the patient selection bias. In conclusion, conservative treatment in calcific tendinitis of the shoulder showed clinically significant improvement, with 72% of excellent or good results. The location of the calcific deposits, initial radiologic type and size, and the extent of initial symptom did not affect the clinical results. In the radiologic type, 46% had a tendency to become more cloudy and inhomogeneous than initial findings, and 62% revealed complete resolution or a decrease in the size of deposits. Because conservative treatment showed good results in most patients, it can be considered as the primary treatment method for calcific tendinitis.
Disclaimer The authors of this article, their immediate families, and any research foundation with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.
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