7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis of the Shoulder Introduction Calcific tendinitis as a source of shoulder pain initially was described more than 100 years ago as Maladie de Duplay. The disease usually is self-limiting and the natural history still is contradictory. (Rupp et al. 2000, Uhthoff and Loehr 1998). Reports concerning the incidence of the dis- ease are inconsistent. Tendon calcifications have been observed in 2.7–20% of patients without pain in their shoulders; calcifying tendinitis has been observed in as many as 17% of shoulders of patients with chronic periarthritis (Bosworth 1941, Hedtmann and Fett 1989, Rowe 1988). Bosworth (1941) describes progressive vanishing of the depos- its in 9.3% of patients within 3 years after the initial diagnosis. Wagenhäuser (1972) reports that deposits disappeared in 27.1% of his patients after 10 years. Treatment of patients with calcific tendon- itis typically is conservative (Farin et al. 1996). If the pain becomes chronic or intermittent after several months of conservative treat- ment, surgical removal has been recom- mended (Uhthoff and Loehr 1998). Success rates above 80% have been reported (Loehr and Uhthoff 1996). Recently, extracorporeal shock wave ther- apy (ESWT) has shown encouraging prelimi- nary results in the treatment of calcific depos- its (Loew et al. 1995, 1999, Rompe et al. 1995, 1998b). The goal of the current study was to compare the efficiency of open surgery and extracorporeal shock wave application (ESWA) in patients with chronic, symptomatic calcifying tendinitis of the supraspinatus ten- don (Rompe et al. 2001b). Materials and Methods Prospectively 79 consecutive patients with a chronic calcifying tendinitis of the supraspi- natus tendon were recruited between 1996 and 1998. All patients had been referred to the author’s shoulder clinic for recalcitrant shoul- der pain by local general practitioners or orthopedic practitioners. All patients had a clinical examination and anteroposterior (A- P) radiographs, acromial outlet views, sonog- raphy, and/or magnetic resonance imaging (MRI) (Wirth et al. 1990). The patients were informed about open surgical removal of the deposit and about high-energy ESWT as a nonsurgical alternative. All patients contacted their health insurance companies and asked for reimbursement of the shock wave therapy (SWT). In 29 cases reimbursement was denied and the patients had to undergo surgery. The remaining 50 patients decided to receive SWT after reimbursement had been offered. So the assignment of the patients to either group was carried out completely independent of our institution. Fig. 7.1aAnteroposterior (A-P) radiograph of a Gaertner III calcium deposit. b Axial radiograph of a Gaertner II calcium deposit. c A-P radiograph showing spontaneous disintegration within 9 weeks. a b c Table 7.1 Methods of treatment before referral to the hospital 1 Treatment Group I (n = 29) Group II (n = 50) Physiotherapy 29 50 Antiinflammatory drugs 29 43 Kryotherapy 29 38 Infiltration with local anesthetic 29 45 Infiltration with steroids 24 23 Needling 918 Radiation therapy 48 1 Number of patients Inclusion Criteria Inclusion and exclusion criteria were identi- cal. All patients reported in this study fulfilled the following criteria. Inclusion criteria were: calcareous deposit on standardized A-P radiographs of a diame- ter of at least 10 mm; the morphology of the deposit had to be homogenous in appearance and with well-defined borders (correspond- ing to Type I in the Gaertner classification of 1993), or inhomogenous in structure with a sharp outline or homogenous in structure with no defined border (corresponding to Type II in the Gaertner classification); shoul- der pain for more than 12 months; clinical signs of subacromial impingement (Hawkins and Kennedy 1980, Neer 1972): unsuccessful conservative therapy in the previous 6 months (Table 7.1); no evidence of bone- related anatomical outlet impingement or functional outlet impingement as seen on radiographs or MRI scans. Exclusion Criteria Exclusion criteria were: cloudy and transpar- ent appearance of the deposit (Type III according to Gaertner 1993); radiological signs of spontaneous resorption (Fig. 7.1); evi- dence of a Type-III acromial morphological feature according to Bigliani et al. (1982) on the outlet view of the acromion; evidence of acute subacromial bursitis; evidence of an acromial spur or acromioclavicular osteophy- tes on the A-P radiographs; evidence of rota- 7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis50 Fig. 7.2aA-P radiograph of a Gaertner III deposit. b A-P radiograph of a Gaertner III after needling and lavage. c Dissolved deposit. a b c tor cuff tears on MRI scans; evidence of func- tional impingement of the rotator cuff on sonographs or Arthro-MRI scans or both; tears of the glenohumeral ligaments of the labrum; hypertrophy of the supraspinatus muscle; dysfunction in the neck (spondylarthritis, cer- vical disc herniation) or thoracic region (hyperkyphosis, spondylarthritis); prior sur- gery to the shoulder; local degenerative dis- ease of the shoulder; rheumatoid arthritis; neurological abnormalities of the upper extremity with calcifying tendonitis; preg- nancy; infection; tumor. Group I The patients in group I underwent surgery as described below. Group I comprised 29 patients (20 women and 19 men), with a mean age of 53 years (range: 31–68 years), and a mean duration of pain of 36.1 ± 28.6 months (range: 12–60 months). There were 19 Type-I deposits and 10 Type-II deposits according to the Gaertner (1993) classifica- tion. The right shoulder was affected in 54% of the patients. Thepatientwasinabeachchairposition with a towel placed under the scapula. With the patient under general anesthesia the rota- tor cuff was exposed through a 5–6 cm–long anterior incision as for an acromioplasty. The deltoid was split parallel to its fibers for no more than 5 cm distal to its acromial attach- ment to prevent damage to the axillary nerve. After partial subdeltoid bursectomy, the rota- tor cuff was exposed. Following identification of the calcium deposit in the supraspinatus tendon either macroscopically or by fluoros- copy, the tendon was incised longitudinally and the calcium was removed by curettage (Fig. 7.3). The defect was closed by means of slowly resorbable sutures. The anterior acro- Materials and Methods 51 Fig. 7.3 Open removal of the calcific deposit. a Skin incision and division of the deltoid muscle ( 5cm).b Partial resection of the subdeltoid bursa. c Longitudinal incision of the supraspinatus tendon. d Extracted deposit. a c b d mial edge was smoothed with a rasp and a drain inserted. Then the deltoid and its fascia were reapproximated with a resorbable vicryl suture, the subcutaneous tissues were closed, and a subcuticular nonresorbable suture was applied for the skin. A sterile dressing was applied. After the operation, the arm was sup- ported by a sling, and pendulum exercises were started after removal of the drain the day after surgery. Passive assisted exercises were performed on the following 3 days, then assisted active motion was done for 4–6 weeks with no limitation on the range of motion (ROM). Group II The patients in group II underwent ESWT. Group II comprised 50 patients (28 women, 22 men), with a mean age of 49.6 ± 7.5 years (range: 31–63 years) and a mean duration of pain of 52.6 ± 54.4 months (range: 12–66 months). There were 28 Type-I deposits and 22 Type-II deposits according to the Gaertner classification. The right shoulder was affected in 56% of the patients. 7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis52 Method of Treatment High-energy ESWT was performed using an experimental device (Siemens AG, Erlangen, Germany), characterized by the integration of an electromagnetic shock wave generator in a mobile fluoroscopy unit. Once the calcium deposit was situated in the center of the C- arm (Fig. 7.4a), the shock wave unit was docked to the shoulder by means of a water- filled cylinder. Standard ultrasound gel was used as a contact medium between cylinder and skin (Fig. 4b). Three thousand impulses of 0.60mJ/mm 2 were administered under regi- nal anesthesia. Only one therapy session was undertaken with each patient. No cold ther- apy or nonsteroidal antiinflammatory drugs (NSAIDs) were allowed after the procedure. Active exercises began as an outpatient treat- mentthedayafterSWTfor4–6weeks. Fig. 7.4aDeposit in the reticule of the fluoroscopy unit of the shock wave device. b High-energy SWA using a fluoroscopy guided shock wave device in plexus anesthesia with the patient under permanent control of an anes- thesiologist. a b Method of Evaluation Follow-up evaluations were done indepen- dently of the treating orthopedic surgeon at 12 months and at 24 months.The University ofCal- ifornia at LosAngeles score for painand function of the shoulder (Kay and Amstutz 1988) was used to grade each patientbeforetreatment and at each follow-up. According to this protocol, pain and function are each rated on a scale of 1–10 points, with 1 point being the worst and 10 points being the best score. The range of active forward flexion and strength in forward flexion were scored from 0–5 points; and the patient’s satisfaction was scored from 0–5 points. The maximum score to be achieved was 35 points. The outcome score was as follows: Excellent = 33 points Good = 29–33 points Poor = 29 points. Method of Evaluation 53 Table 7.2 Points 1 according to the University of California at Los Angeles Rating System Group I Group II p-value Follow-up (months) Total Gaertner I Gaertner II Total Gaertner I Gaertner II Total Gaertner I Gaertner II 0 17.8±4.0 18.0±3.4 17.4±4.7 19.0±3.3 18.7±3.2 19.2±4.8 – – – 12 30.3±3.2 29.3±3.8 31.7±4.5 28.3±6.9 26.7±3.6 30.6±4.3 – .01 – 24 32.4±2.9 32.0±4.1 33.1±3.9 29.1±4.2 26.7±3.6 31.9±4.7 .001 .0001 – 1 Mean±standard deviation Radiological Evaluation An A-P view (Kilcoyne et al. 1989) and an out- let view of the acromion were obtained 1 day before surgery or ESWT and at 12 months after either treatment. On the A-P views, resorption was graded as none, partial, or complete by the author’s colleagues from the local Department of Radiology, who were blinded as to the treatment status and ante- cedent studies. Statistics Statistical analysis was done by the local Insti- tute of Medical Statistics and Documentation. Differences between the groups regarding pain, function, flexion, strength, and total out- come were tested by using the Wilcoxon test for two independent samples. The Fisher exact test for 2 × 2 contingency tables was used for the analysis of satisfaction and out- come, and its extended version was used to test the removal of the calcific deposits and thetimeuntilthepatientsreturnedtowork. Thecomparisonofpreoperativedatawith data from the 12-month and 24-month follow-up was done by means of the Wilcoxon signed rank test for pain, function, flexion, strength, and total outcome. Differences in time concerning the patients’ satisfaction and the outcome were done by the McNemar test. Dependencies between removal of the deposit, return to work, and outcome were tested with the Fisher exact test and its exten- sion. Differences in total outcome scores according to different radiological outcome and removal of the deposits were shown with the Wilcoxon test. The level of significance was set at 95% for each test; therefore p- values 0.05 were considered to be signifi- cant. All tests were calculated two-sided; multiple adjustment was not done. Results Rate of Follow-up At 12 months, 20 patients in group I and 45 patients in group II were examined. At 24 months, 20 patients in group I and 39 patients ingroupIIwereexamined.Theremaining patients were lost to follow-up. Regarding the epidemiolgical data, the patients who were lost to follow-up did not differ from the patients included in the current study. Clinical Outcome in the University of California Los Angeles Score The total outcome in the University of Califor- nia Los Angeles score is shown in Tables 7.2 and 7.3. The comparison of the two groups regarding point values or regarding “Excel- lent” and “Good” outcomes showed no signifi- cant difference at 12 months. At 24 months, point values were significantly higher in group I than in group II (32.4 and 29.1 points, respectively; p 0.001), and there were sig- 7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis54 Table 7.3 Outcome according to the University of California at Los Angeles Rating System 1 Group I Group II p-value Total Gaertner I Gaertner II Total Gaertner I Gaertner II Follow- up (mo) E 2 G 3 P 4 EGPEGP EGPEGPEGP Total Gaertner I Gaertner II 0 ––100––100––100 ––100––100––100 – – – 12 50 25 25 42 33 25 63 12 25 40 20 40 28 20 52 55 20 25 – .01 – 24 55 35 10 50 42 8 63 25 12 46 18 36 43 10 47 56 28 16 .05 .0001 – 1 Percentage of patients 2 Excellent 3 Good 4 Poor Fig. 7.5aA-P radiograph showing a Gaertner I cal- cium deposit (homogenous structure with well- defined borders). b A-P radiograph showing complete disintegration 12 months after SWA. a b nificantly more “Excellent” and “Good” results in group I than in group II (90% and 64%, respectively; p 0.05). Radiological Outcome Table 7.4 shows the extent of calcium elimina- tion in relation to its radiomorphological fea- tures. Group I: At 12 months, the calcium deposit had disappearded in 85% of the patients; in 15% of the patients only minor particles were observed. Results 55 Table 7.4 Elimination rates of the calcific deposit Group I Group II Elimination of deposit 1 Gaertner I (n=12) Gaertner II (n= 8) Gaertner I (n=25) Gaertner II (n=20) Complete 84% 88% 28% 70% Partial 16% 12% 36% 30% None –– 36%– 1 12-month follow-up Fig. 7.6aA-P radiograph showing a Gaertner II deposit (inhomogenous structure with well-defined border). b A-P radiograph showing complete disinte- gration 12 months after SWA. a b Group II: At 12 months, complete resorption was observed in 47% of the patients (Figs. 7.5, 7.6) and partial resorption of the calcium deposit was observed in 33% of the patients. In 20% of the patients there was no change in the radiomorphological features at all. The calcium deposit was no longer detect- able radiologically in significantly more patients in group I than in group II (p 0.0001). Complete disintegration of the calcium was found significantly more often in Gaertner Type-II deposits than in Gaertner Type-I deposits after SWT (70% and 28%, respectively; p 0.0001). Radiomorphological Features and Clinical Outcome In group I Gaertner Type-I patients achieved 29.3 points at 1 year and 32.0 points at 2 years; Gaertner Type-II patients had 31.7 pointsat1yearand33.1pointsat2years. IngroupIIGaertnerType-Ipatients achieved 26.7 points at 1 year and at 2 years. Gaertner Type-II patients had 30.6 points at 1 year and 31.9 points at 2 years. Gaertner Type-I patients showed signifi- cantly better point values in the University of California at Los Angeles score in group I than in group II at both follow-ups (all p 0.0001). There was no significant difference between Gaertner Type-II patients in group I and group II (Table 7.2). In group I patients with a Gaertner Type-I deposit had “Excellent/Good” outcomes in 75% of cases at 1 year and in 92% at 2 years. Patients with a Gaertner Type-II deposit showed “Excellent/Good” results in 75% of cases at 1 year and in 88% at 2 years. In group II 48% of the patients with a Gaert- ner Type-I deposit had “Excellent/Good” out- comesat1year,andin53%ofcasesat2years. 7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis56 Fig. 7.7 Hematoma after high-energy ESWT in the contact area of shock wave device and skin. Patients with a Gaertner Type-II deposit achieved “Excellent/Good” outcomes in 75% of cases at 1 year, and in 84% at 2 years. At both follow-ups there were significantly more “Excellent/Good” outcomes in Gaertner Type-I patients in group I than in group II (12 months: p 0.01; 24 months: p 0.0001). There was no significant difference concern- ing Gaertner Type-II patients between group I and group II (Table 7.3). Hospital Stay Patients in group I remained in hospital for an average of 12 ± 4.5 days; patients in group II for3.1±0.65days.Sotheperiodofhospital- ization was significantly shorter in group II (p 0.0001),resultinginanaveragecost advantage in group II of US$ 2970 per patient. Absence from Work After dismissal from the hospital it took patients in group I an average of 9.1 ± 11.6 weekstoreturntowork,andpatientsingroup II 2.5 ± 3.0 weeks. Absence from work was sig- nificantly shorter in group II (p 0.01), result- ing in an average cost advantage of US$ 9240 per patient. Complications Although one deep wound infection was observed in a patient from group I, no side effects except for transient subcutaneous hematomas were observed in patients from group II (Fig. 7.7). Lesions in the rotator cuff were ruled out after SWT by MRI or through ultrasonography. Subjective Rating At 24 months 55% of the patients in group I reported a complete relief from pain and 29% a significant reduction in pain. Five percent and 11% of the patients observed only slight or no improvement, respectively. In group II there 43% of patients were with- outpainand24%withasignificantreduction in pain. Four percent and 29% of the patients had a slight relief or no reduction in pain, respectively. With the numbers available we could not detect a significant difference between group I and group II. Discussion The usual conservative treatment of the chronic or subacute phase of calcifying tendi- nitis comprises physical therapy, infiltration with local anesthetics or corticosteroids, or both, and needling and lavage. Success rates reported vary between 30% and 85% (De Palma and Kruper 1961, Gaertner 1993, Har- mon 1958, Lapidus 1943, Pfister and Gerber 1994, Reichelt 1996, Wainner and Hasz 1998). In a series of 100 patients treated conserva- tively, Litchman et al. 1968 report only one patient who had to undergo surgery. The effect of ultrasonic energy is questionable (Griffin and Karselis 1982). Radiation therapy is not an acceptable mode of treatment accordingtostudiesbyChapman(1942), Young (1946), and Plenk (1952). Open surgery is regarded as a dependable and quick method to relieve the deposit. Vebostad (1975) report excellent and good results in 34 out of 43 patients (79%), and Gschwend et al. (1981) report excellent and Discussion 57 good results in 25 out of 28 patients (89%). Rubenthaler and Wittenberg (1997) observed 88% excellent and good results. Rochwerger et al . (1999), also using the open procedure, report an increase of the Constant score val- uesfrom52to89pointsafterafollow-upof 23 months. The endeavor to avoid damage to the del- toid muscle led to the development of mini- mally invasive techniques, guided by arthros- copy (Ellman 1987, Ellman and Kay 1991, Esch et al. 1988, Gartsman et al. 1988). This techni- cally demanding procedure has proved to be successful in prospective studies (Altchek et al. 1990, Ark et al. 1992, Ellman and Kay 1991, Habermeyer et al. 1998, Sachs et al. 1994). Ark et al. (1992) observed 50% excellent results. Mol´eetal . (1993) report 82% of their patients to be satisfied with the postoperative out- come. Similar to Jerosch et al. (1998) and Re and Karzel (1993), the authors show an improvement in results with an associated acromioplasty. All authors, with the exception of Tillander and Norlin (1998), stress the importance of complete removal of the cal- cicfic deposit; subacromial decompression was thought to be of minor importance. In a preliminary study, Loew et al. (1995) discuss the potential disintegrating capability of extracorporeal shock waves regarding cal- cific deposits of the rotator cuff. They pro- posed that increasing pressure within the therapeutic focus caused fragmentation and cavitation effects inside the amorphic calcifi- cations and led to disorganization and disinte- gration of the deposits. A breakthrough of the calcific masses into the adjacent subacromial bursa or local resorptive reaction of the sur- rounding tissue induced by extracorporeal shock waves possibly led to the disappearance of the deposits. The exact working mechanism remains unclear. In an in vitro study, Perlick et al. (1999b) put artificial concrements in the rotator cuff of a pig and reported that it took at least 2000–3000 impulses of an energy flux density of 0.42 mJ/mm 2 to achieve a disinte- gration of the deposit. Clinically, Loew et al. (1995) report signifi- cant improvement of symptoms in 14 out of 20 patients (70%) after two applications of 2000 shock waves of an energy flux density of 0.3 mJ/mm 2 . Radiologically, there were seven cases of complete resorption and five cases of partial disintegration. However, the follow-up was at only 12 weeks. Radiologically, these results are much better than the data reported in the author’s first preliminary series (Rompe et al. 1995) in which complete elimination of the deposit was observed in only 15% of 40 patients who were treated once with 1500 impulses of an energy flux density of 0.28 mJ/ mm 2 . Daecke et al. (1997) showed an influ- ence of two applications versus one applica- tion of 2000 shock wave impulses of an energy flux density of 0.3 mJ/mm 2 in 115 patients. Complete elimination of the deposit was seen on radiographs in 54% of patients (two treatments) and in 33% of patients (one treatment), and partial disintegration was seen in 23% of patients (one treatment) and 14% of patients (two treatments). The differ- ences in the radiological findings were signifi- cant in favor of two applications. Clinically, 54%ofpatientsversus45%ofpatientsdidnot have pain after 6 months, and 75% of patients versus 65% of patients attained at least 75% of the age- and gender-dependent values of the score of Constant and Murley (1987). How- ever, the differences between the two treat- ment groups were not statistically significant. Krischek et al. (1997) observed 50 patients for 1 year after one application of 3000 shock waves of an energy flux density of 0.28 mJ/ mm 2 . Thirty-four percent of the patients were satisfied and 18% of patients were moderately satisfied. Radiologically, deposits had been eliminated completely in eight patients, whereas 21 patients had a partial disintegra- tion. According to the Gaertner classification, they observed changes of the radiomorpho- logical features in 88% of Type-II deposits, but in only 44% in Type-I deposits. Clinically, the Constant and Murley score values improved from 60 to 76 points. Therefore, by doubling the number of applied shock waves compared with previous studies, neither an increase in the elimination rate nor an improvement in the clinical outcome was achieved. Eighteen 7 Extracorporeal Shock Wave Application in the Treatment of Chronic Calcifying Tendinitis58 . 28% 70 % Partial 16% 12% 36% 30% None –– 36%– 1 12-month follow-up Fig. 7. 6aA-P radiograph showing a Gaertner II deposit (inhomogenous structure with well-defined border). b A-P radiograph showing. with well-defined borders (correspond- ing to Type I in the Gaertner classification of 1993), or inhomogenous in structure with a sharp outline or homogenous in structure with no defined border. and Clinical Outcome In group I Gaertner Type-I patients achieved 29.3 points at 1 year and 32.0 points at 2 years; Gaertner Type-II patients had 31 .7 pointsat1yearand33.1pointsat2years. IngroupIIGaertnerType-Ipatients achieved