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Journal of Shoulder and Elbow Surgery

Effectiveness of physical therapy in treating atraumatic full-thickness rotator cuff tears: a multicenter prospective cohort study

Published:March 28, 2013DOI:https://doi.org/10.1016/j.jse.2013.01.026

      Purpose

      To assess the effectiveness of a specific nonoperative physical therapy program in treating atraumatic full-thickness rotator cuff tears using a multicenter prospective cohort study design.

      Materials and methods

      Patients with atraumatic full-thickness rotator cuff tears who consented to enroll provided data via questionnaire on demographics, symptom characteristics, comorbidities, willingness to undergo surgery, and patient-related outcome assessments (Short Form 12 score, American Shoulder and Elbow Surgeons score, Western Ontario Rotator Cuff score, Single Assessment Numeric Evaluation score, and Shoulder Activity Scale). Physicians recorded physical examination and imaging data. Patients began a physical therapy program developed from a systematic review of the literature and returned for evaluation at 6 and 12 weeks. At those visits, patients could choose 1 of 3 courses: (1) cured (no formal follow-up scheduled), (2) improved (continue therapy with scheduled reassessment in 6 weeks), or (3) no better (surgery offered). Patients were contacted by telephone at 1 and 2 years to determine whether they had undergone surgery since their last visit. A Wilcoxon signed rank test with continuity correction was used to compare initial, 6-week, and 12-week outcome scores.

      Results

      The cohort consists of 452 patients. Patient-reported outcomes improved significantly at 6 and 12 weeks. Patients elected to undergo surgery less than 25% of the time. Patients who decided to have surgery generally did so between 6 and 12 weeks, and few had surgery between 3 and 24 months.

      Conclusion

      Nonoperative treatment using this physical therapy protocol is effective for treating atraumatic full-thickness rotator cuff tears in approximately 75% of patients followed up for 2 years.

      Level of evidence

      Keywords

      Rotator cuff tears are extremely common, affecting at least 10% of persons aged older than 60 years in the United States.
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      By use of 2010 US census data, this equates to over 5.7 million persons.

      Werner CA. The older population. 2010 Census Briefs. C201 OBR-09. US Department of Commerce, Economics and Statistics Administration, US Census Bureau. Available from: URL: http://www.census.gov/prod/cen2010/briefs/c2010br-09.pdf. Accessed September 12, 2012.

      Industry estimates suggest that rotator cuff surgeries are performed on between 75,000 and 250,000 patients per year in the United States.
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      These data show that fewer than 5% of patients with rotator cuff tears in the United States are treated surgically.
      Interestingly, in patients who do have surgical repair of rotator cuff tears, the failure rate is between 25% and 90%,
      • Bishop J.
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      Prospective evaluation of the effect of rotator cuff integrity on the outcome of open rotator cuff repairs.
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      • et al.
      Surgically repaired massive rotator cuff tears: MRI of tendon integrity, muscle fatty degeneration, and muscle atrophy correlated with intraoperative and clinical findings.
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      Prediction of rotator cuff repair results by magnetic resonance imaging.
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      • Hodler J.
      • Gerber C.
      MR imaging after rotator cuff repair: full-thickness defects and bursitis-like subacromial abnormalities in asymptomatic subjects.
      yet patients whose repairs fail report satisfaction levels and outcome scores that are nearly indistinguishable from those whose repairs are intact.
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      • Seroyer S.T.
      • Frank R.M.
      • et al.
      Does the literature confirm superior clinical results in radiographically healed rotator cuffs after rotator cuff repair?.
      Because most patients in these studies undergo postoperative physical therapy, it is conceivable that the postoperative physical therapy may be responsible for the improvements in outcome. Finally, a number of retrospective case series
      • Ainsworth R.
      • Lewis J.S.
      Exercise therapy for the conservative management of full thickness tears of the rotator cuff: a systematic review.
      and 1 randomized controlled trial
      • Moosmayer S.
      • Lund G.
      • Seljom U.
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      • Hennig T.
      • Tariq R.
      • et al.
      Comparison between surgery and physiotherapy in the treatment of small and medium-sized tears of the rotator cuff; a randomized controlled study of 103 patients with one-year follow up.
      have suggested that nonoperative treatment of full-thickness rotator cuff tears may be successful in some patients.
      These data led to the hypothesis that physical therapy may be effective in treating patients with symptomatic atraumatic full-thickness rotator cuff tears. In 2009, we published a systematic review on the effectiveness of exercise on treating rotator cuff impingement syndrome and offered a synthesized physical therapy protocol.
      • Kuhn J.E.
      Exercise in the treatment of rotator cuff impingement: a systematic review and a synthesized evidence-based rehabilitation protocol.
      The specific objectives of this multicenter prospective cohort study are (1) to determine the effectiveness of this rehabilitation protocol in treating patients with atraumatic rotator cuff tears, with failure defined as patients electing to have surgery, and (2) to determine the effect of this nonoperative physical therapy protocol on patient-reported measures of outcome.

      Materials and methods

      The MOON (Multicenter Orthopaedic Outcomes Network) Shoulder Group is a team of 16 fellowship-trained orthopaedic surgeons and research personnel from 9 geographically dispersed sites within the United States, representing both academic and private practice patient environments. This group was formed to conduct large multicenter studies on conditions of the shoulder.
      From May 2004 through October 2006, the MOON Shoulder Group met regularly to formulate research questions of interest; develop and standardize radiographic and magnetic resonance imaging (MRI) protocols; assemble validated behavioral and patient-oriented outcome assessment forms for data collection; and conduct validation studies on MRI classification of rotator cuff tears,
      • Spencer E.E.
      • Dunn W.R.
      • Wright W.R.
      • Wolf B.
      • Spindler K.P.
      • McCarty E.
      • et al.
      Interobserver agreement in the classification of rotator cuff tears using magnetic resonance imaging.
      rotator cuff tear classification based on arthroscopic videos,
      • Kuhn J.E.
      • Dunn W.R.
      • Ma B.
      • Wright R.W.
      • Jones G.
      • Spencer E.E.
      • et al.
      Interobserver agreement in the classification of rotator cuff tears.
      and radiographic findings associated with rotator cuff disease.
      • Baumgarten K.
      • Carey J.L.
      • Aboud J.A.
      • Jones G.L.
      • Kuhn J.E.
      • Wolf B.R.
      • et al.
      Reliability of determining and measuring acromial enthesophytes.
      In addition, the group performed systematic reviews of the literature to evaluate postoperative rotator cuff repair rehabilitation,
      • Baumgarten K.M.
      • Vidal A.F.
      • Wright R.W.
      Rotator cuff repair rehabilitation: level I and II systematic review.
      summarize the literature regarding indications for surgical treatment of rotator cuff tears,
      • Oh L.S.
      • Wolf B.R.
      • Hall M.P.
      • Levy B.A.
      • Marx R.G.
      Indications for rotator cuff repair. A systematic review.
      • Wolf B.R.
      • Dunn W.R.
      • Wright R.W.
      Indications for repair of full-thickness rotator cuff tears.
      and determine the effectiveness of physical therapy in treating rotator cuff disease and develop a standard physical therapy protocol based on the evidence.
      • Kuhn J.E.
      Exercise in the treatment of rotator cuff impingement: a systematic review and a synthesized evidence-based rehabilitation protocol.
      With regard to atraumatic rotator cuff tears, the indications for surgery are not clear,

      Dunn WR, An A, Khazzam MS, Baumgarten KM, Bishop JY, Brophy RH, et al. Symptoms of pain do not correlate with rotator cuff tear severity. Presented at the American Academy of Orthopaedic Surgeons Annual Meeting, San Diego, CA, February 16, 2011.

      • Oh L.S.
      • Wolf B.R.
      • Hall M.P.
      • Levy B.A.
      • Marx R.G.
      Indications for rotator cuff repair. A systematic review.
      • Wolf B.R.
      • Dunn W.R.
      • Wright R.W.
      Indications for repair of full-thickness rotator cuff tears.
      and our research group could not develop standard indications for surgery by consensus. Therefore, the group decided to conduct a prospective cohort study on the nonoperative treatment of atraumatic full-thickness rotator cuff tears using the physical therapy protocol derived from the systematic review.
      • Kuhn J.E.
      Exercise in the treatment of rotator cuff impingement: a systematic review and a synthesized evidence-based rehabilitation protocol.
      We expected that some patients would be successfully treated and decline surgical intervention whereas nonoperative treatment would fail in others and they would undergo rotator cuff repair. By identifying features that distinguish these groups, we expect to have insight into appropriate indications for surgery. This article documents the demographic data of this cohort and reports on the success of nonoperative treatment in the first 422 patients enrolled in this study who have follow-up of at least 12 weeks.

       Inclusion and exclusion criteria

      All patients aged 18 to 100 years with shoulder symptoms and MRI-documented, atraumatic, full-thickness rotator cuff tears were invited to participate. Any patient with a history of an injury leading to his or her presenting symptoms was excluded. Other exclusion criteria included pain related to the cervical spine, scapular pain, previous shoulder surgery, glenohumeral arthritis, inflammatory arthritis, adhesive capsulitis, previous proximal humeral fracture, bilateral rotator cuff tears, and dementia.

       Protocol

      All patients who met inclusion criteria were offered an opportunity to enroll in the study. At the initial visit, patients completed a questionnaire that detailed demographic data and included validated patient-reported outcome measures (Short Form 12 [SF-12] score,
      • Ware J.E.
      • Kosinski M.
      • Keller S.D.
      A 12-Item Short-Form Health Survey: construction of scales and preliminary tests of reliability and validity.
      American Shoulder and Elbow Surgeons [ASES] score,
      • Richards R.R.
      • An K.-N.
      • Bigliani L.U.
      • Friedman R.J.
      • Gartsman G.M.
      • Gristina A.G.
      • et al.
      A standardized method for the assessment of shoulder function.
      Western Ontario Rotator Cuff [WORC] index score,
      • Kirkley A.
      • Alvarez C.
      • Griffin S.
      The development and evaluation of a disease-specific quality-of-life questionnaire for disorders of the rotator cuff: the Western Ontario Rotator Cuff Index.
      Single Assessment Numeric Evaluation [SANE] score,
      • Williams G.N.
      • Gangel T.J.
      • Arciero R.A.
      • Uhorchak J.M.
      • Taylor D.C.
      Comparison of the single assessment numeric evaluation and two shoulder rating scales. Outcomes measures after shoulder surgery.
      and Shoulder Activity Scale
      • Brophy R.H.
      • Beauvais R.L.
      • Jones E.C.
      • Cordasco F.A.
      • Marx R.G.
      Measurement of shoulder activity level.
      ). Physicians performed a standard physical examination and reviewed radiographs and MRI images for each patient and then recorded information on standard Teleform data collection forms (Cardiff, Vista, CA, USA).

       Physical therapy program

      Patients were given 2 instructive rehabilitation books (Appendix 1, available on the journal’s website at www.jshoulderelbow.org)—one for physical therapists and another for home-based physical therapy written at the eighth-grade level with an accompanying DVD. This physical therapy program was derived from a systematic review of the literature that showed that exercise was effective in treating impingement syndrome.
      • Kuhn J.E.
      Exercise in the treatment of rotator cuff impingement: a systematic review and a synthesized evidence-based rehabilitation protocol.
      The specific exercises included daily range of motion (postural exercises, active-assisted motion, active training of scapular muscles, active range of motion); daily flexibility (anterior and posterior shoulder stretching); and strengthening 3 times per week (rotator cuff and scapula exercises). Therapists were instructed to provide manual mobilization exercises as needed, because there is evidence to support their use in impingement,
      • Kuhn J.E.
      Exercise in the treatment of rotator cuff impingement: a systematic review and a synthesized evidence-based rehabilitation protocol.
      and to progress the patient to a home therapy program when ready. Heat and cold were recommended as modalities, but ultrasound was not. Patients completed a compliance diary regarding their physical therapy visits and the frequency of home therapy events.
      Patients returned after performing the therapy program for 6 weeks. At that point, patients were given 3 options: (1) If they considered themselves “cured,” no additional treatment or formal follow-up was prescribed. (2) If they were “improved,” patients continued the physical therapy program for another 6 weeks. (3) If they were “no better,” they could elect to have surgery. Patients could choose to have surgery at any time in the course of treatment.

       Outcome measures

      Patient demographic information including age, gender, race, employment status, workers’ compensation or automobile claims, tobacco history, and comorbidities was collected at entry into the study. Data on whether the patients had undergone surgery for their rotator cuff tear were collected at each follow-up time point. The following patient-related measures of outcome were collected at study entry, 6 weeks, 12 weeks, 1 year, and 2 years: SF-12 score,
      • Ware J.E.
      • Kosinski M.
      • Keller S.D.
      A 12-Item Short-Form Health Survey: construction of scales and preliminary tests of reliability and validity.
      ASES score,
      • Richards R.R.
      • An K.-N.
      • Bigliani L.U.
      • Friedman R.J.
      • Gartsman G.M.
      • Gristina A.G.
      • et al.
      A standardized method for the assessment of shoulder function.
      WORC index score,
      • Kirkley A.
      • Alvarez C.
      • Griffin S.
      The development and evaluation of a disease-specific quality-of-life questionnaire for disorders of the rotator cuff: the Western Ontario Rotator Cuff Index.
      SANE score,
      • Williams G.N.
      • Gangel T.J.
      • Arciero R.A.
      • Uhorchak J.M.
      • Taylor D.C.
      Comparison of the single assessment numeric evaluation and two shoulder rating scales. Outcomes measures after shoulder surgery.
      and Shoulder Activity Scale.
      • Brophy R.H.
      • Beauvais R.L.
      • Jones E.C.
      • Cordasco F.A.
      • Marx R.G.
      Measurement of shoulder activity level.
      At the initial visit, physicians completed a data collection form that included findings from the physical examination, as well as interpretation of radiographs and MRI grading of the rotator cuff tear.
      • Spencer E.E.
      • Dunn W.R.
      • Wright W.R.
      • Wolf B.
      • Spindler K.P.
      • McCarty E.
      • et al.
      Interobserver agreement in the classification of rotator cuff tears using magnetic resonance imaging.
      Physical examination data were also collected at the 6- and 12-week visits.

       Statistical methods

      Most epidemiologic data are presented as descriptive data in table form. Comparisons of patient-related outcome scores were analyzed with a Wilcoxon signed rank test with continuity correction. Failure of nonoperative treatment data is presented as descriptive data and was analyzed with a Kaplan-Meier survivorship curve. Statistical analysis was performed with free open-source R statistical software (R Foundation for Statistical Computing, Vienna, Austria).

      Results

       Enrollment

      The group saw 2233 rotator cuff tear patients during the enrollment period. Of these patients, 1280 were excluded for the following reasons: acute tears (38%), previous surgery (11%), bilateral disease (8%), neck disorders (6%), frozen shoulder (2%), dislocation (3%), rheumatoid disease (1%), and fracture (1%). Of the remaining 953 patients eligible to enroll in the study, 452 (47%) elected to do so. These 452 patients are followed up as a prospective cohort with rolling entry into the study. Of this group, 30 patients withdrew from the study. This report is based on 422 patients for whom we have follow-up data at a minimum of 3 months and with up to 2 years’ follow-up for 90% of the cohort (n = 381).
      The mean age of patients who enrolled was 62 years, whereas the mean age of those who did not was 58 years (P < .001). Equal numbers of men and women enrolled, whereas of those who did not enroll, men predominated (63%). This difference was statistically significant (P < .001).

       Demographic data for study population

      The mean age of the study population was 62.6 years (range, 31-90 years), with 206 men (51%) and 194 women (49%). The dominant arm was affected in 68% of subjects. The right arm was affected in 70% of subjects. With regard to tobacco use, 89.5% were nonsmokers. Other demographic features, including race, ethnicity, education level, and employment status, are listed in Table I, Table II, Table III, Table IV. Many patients had comorbidities, with hypertension, back pain, and osteoarthritis most common (Table V). Geographically, the patient mix was fairly well distributed (Table VI). Interestingly, only 18% of patients reported a family history of rotator cuff problems, whereas 60% did not. With regard to treatment before enrolling in the study, 23% of patients had already tried some physical therapy, 40% had received injections, and 80% had tried nonsteroidal anti-inflammatory drugs.
      Table IRace characteristics of study population
      RaceNo. (%)
      White345 (86)
      Black32 (8)
      Asian12 (3)
      American Indian6 (1.5)
      Hawaiian1 (<1)
      No answer8 (2)
      Table IIEthnicity of study population
      EthnicityNo. (%)
      Hispanic11 (2.5)
      Not Hispanic319 (80)
      No answer70 (17.5)
      Table IIIEducation level of study population
      Education levelNo. (%)
      No high school14 (3.5)
      Some high school15 (4)
      High school graduate/GED96 (24)
      Some college85 (21)
      Associate degree20 (5)
      Bachelor’s degree77 (19)
      Graduate degree92 (23)
      No answer1 (<1)
      Table IVEmployment status of study population
      Employment statusNo. (%)
      Full time187 (47)
      Part time38 (9.5)
      Retired130 (32.5)
      Homemaker17 (4)
      Unemployed6 (1.5)
      Disabled21 (5)
      No answer1 (<1)
      Table VComorbidities of study population
      ComorbiditiesNo. (%)
      Hypertension197 (49)
      Back pain146 (36.5)
      Osteoarthritis/degenerative arthritis133 (33)
      Other medical problems102 (25.5)
      Depression69 (17)
      Heart disease62 (15.5)
      Diabetes54 (13.5)
      Rheumatoid arthritis32 (8)
      Cancer30 (7.5)
      Ulcer/stomach disease27 (7)
      Lung disease24 (6)
      Anemia/other blood disease20 (5)
      Kidney disease13 (3)
      Liver disease7 (2)
      Table VIGeographic distribution of study population
      SiteNo. (%)
      Vanderbilt University, Nashville, TN, USA92 (23)
      The Ohio State University, Columbus, OH, USA84 (21)
      Washington University in St Louis, St Louis, MO, USA40 (10)
      Knoxville Orthopaedic Clinic, Knoxville, TN, USA40 (10)
      Orthopaedic Institute, Sioux Falls, SD, USA36 (9)
      University of California, San Francisco, CA, USA36 (9)
      Hospital for Special Surgery, New York, NY, USA30 (8)
      University of Colorado, Denver, CO, USA27 (7)
      University of Iowa, Iowa City, IA, USA15 (4)

       MRI features of rotator cuff tears

      Superior humeral head migration was recognized on MRI in 15% of patients. Tears involving only the supraspinatus were seen in 70% of patients (Table VII). Tear size was minimal in 48% of patients and was retracted to the mid humeral head in 33.5% of patients (Table VIII).
      Table VIIMRI size of tear based on number of tendons involved
      Tendon involvementNo. (%)
      Supraspinatus only281 (70)
      Supraspinatus and infraspinatus83 (21)
      Supraspinatus, infraspinatus, and teres minor3 (<1)
      Subscapularis2 (<1)
      Supraspinatus and subscapularis20 (5)
      Supraspinatus, infraspinatus, and subscapularis7 (2)
      Unknown4 (1)
      Table VIIIDegree of rotator cuff retraction in coronal plane on MRI
      Degree of retractionNo. (%)
      Minimal191 (48)
      Mid humeral134 (33.5)
      Glenohumeral52 (13)
      Medial to glenoid19 (5)
      Unknown4 (1)

       Compliance with physical therapy program

      Overall, 77.7% of patients submitted their physical therapy compliance diaries. In the first 6 weeks of treatment, most patients performed both supervised and home physical therapy. Patients averaged only 8 supervised physical therapy visits over the first 6 weeks. During the second 6 weeks of physical therapy, a higher proportion of patients did only home therapy, with a mean of 7 visits of supervised therapy over the 6-week period (Table IX).
      Table IXCompliance with physical therapy program
      No. who returnedNo therapySupervised and homeSupervised onlyHome onlyMean No. of supervised visits
      1-6 wk230/291 (79%)41805418
      7-12 wk143/206 (69%)2661677

       Improvements in range of motion

      Average active range of motion progressively improved over the 12-week period of treatment, notably for forward elevation and abduction (Table X).
      Table XImprovement in active range of motion during treatment
      Active motionBaseline (N = 452)6 wk (n = 402)12 wk (n = 399)
      Forward elevation (°)149.8163.3162.9
      Abduction (°)136.8154.9154.7
      External rotation at side (°)52.955.655.8
      Internal rotation at side (°)56.756.958.3
      External rotation at 90° of abduction (°)74.880.380.9
      Internal rotation at 90° of abduction (°)45.346.452.3

       Improvements in patient-reported measures of outcome

      Statistically and clinically significant improvements were noted over the 12-week period of treatment for the ASES, WORC, and SANE scores (Table XI). No clinically important change was noted for the SF-12 domains or the Shoulder Activity Scale.
      Table XIPatient-reported measures of outcome
      Assessment toolBaseline (N = 452)6 wk (n = 402)P value12 wk (n = 399)P value
      SF-12 MCS40.340.6.3640.8.895
      SF-12 PCS35.335.6<.000136.1<.0001
      ASES score54.578.0<.000183.7<.0001
      WORC score47.262.5<.000169.7<.0001
      SANE score46.662.7<.000170.3<.0001
      Marks Activity Scale9.910.2.09610.0.47
      MCS, mental component score; PCS, physical component score.
      Patient-reported measures of outcome are compared with baseline scores with P values.

       Failure of nonoperative treatment: surgery rates

      The cohort of patients was collected over a 3-year period, and this report is a cross-sectional study of the cohort when all members of the cohort had reached 1-year follow-up and 75% of the cohort had reached 2-year follow-up. The data presented are a cross-sectional evaluation of patients in the cohort based on different time points as of March 2012.
      All patients in the cohort have reached the 6-week time point (n = 422). Of this group, we have data on 402 patients (95%) at 6 weeks. Of this group, 35 patients (9%) had elected to have surgery within 6 weeks of starting the physical therapy program (Fig. 1).
      Figure thumbnail gr1
      Figure 1Six-week data. The entire cohort of 422 patients has reached the 6-week follow-up point. Of this group, 20 patients (5%) were lost to follow-up. Of the 402 patients remaining, 35 had surgery (9%).
      All of the patients in the cohort have reached the 12-week follow-up point, and we have complete data on 399 (95%). An additional 24 patients elected to have surgery between 6 and 12 weeks after starting the physical therapy program; as such, the total number of patients who had decided to have surgery at 12 weeks was 59 (15%) (Fig. 2).
      Figure thumbnail gr2
      Figure 2Twelve-week data. The entire cohort of 422 patients has reached the 12-week follow-up point. Of this group, 23 (5%) were lost to follow-up. Of the 399 patients remaining, 59 had surgery (15%).
      All patients in the cohort have reached the 1-year follow-up point. We have data on 396 (94%). At 1-year follow-up, 82 patients (21%) had elected to undergo surgery (Fig. 3).
      Figure thumbnail gr3
      Figure 3One-year data. The entire cohort of 422 patients has reached the 1-year follow-up point. Of this group, 26 (6%) were lost to follow-up. Of the 396 patients remaining, 82 had surgery (20%).
      As of March 2012, 381 of the 422 patients in the cohort (90%) had reached the 2-year follow-up point. Of this group, 319 patients had data available (84% follow-up). Of this group, 82 patients had decided to have surgery (26%) (Fig. 4).
      Figure thumbnail gr4
      Figure 4Two-year data. As of March 2012, 381 patients have been enrolled in the study for at least 2 years. Of this group, 62 (16%) were lost to follow-up. Of the 319 patients remaining, 82 had surgery (26%).
      Kaplan-Meier survivorship analysis shows that patients who elect to undergo surgery do so within 12 weeks. If a patient avoids surgery in the first 12 weeks, he or she is unlikely to undergo surgery at a later time point, up to 2 years (Fig. 5).
      Figure thumbnail gr5
      Figure 5Kaplan-Meier survival analysis curve: failure of physical therapy as a treatment for atraumatic rotator cuff tears. It should be noted that the physical therapy program fails in most patients and they elect to have surgery between 6 weeks (42 days) and 12 weeks (84 days) after initiating the therapy program.

      Discussion

      The key findings of this study are that physical therapy is effective in the nonoperative treatment of atraumatic full-thickness rotator cuff tears as shown by the surprisingly low rate of surgery, as well as the significant improvements in validated patient-related scores of outcome. It is interesting to note that in most patients in whom nonoperative treatment failed, this failure occurred within the first 12 weeks. It is also of interest that only approximately 1 supervised physical therapy visit per week was required during the typical 12-week course of treatment.
      Limitations of this study include the potential for selection bias (eg, patients who are less interested in surgery may be more inclined to participate, or the decision to have surgery may be influenced by the type of insurance a patient may have) or performance bias (some patients may have received medications, acupuncture, or other pain-relieving treatments that we did not examine). Moreover, generalizability may be limited because patients who presented with a history of trauma were excluded from the study. In addition, this report is a cross-sectional study of the data as they stand today. The data could potentially change as the cohort continues to move through time.
      Despite these potential limitations, our study included patients from multiple practices across the United States, has 400 subjects, and was performed as a prospective cohort study. As such, for atraumatic rotator cuff tears, the results of this study may be generalized to the US population.
      Substantial variation has been noted geographically in the frequency of rotator cuff surgery,
      • Vitale M.G.
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      • Arons R.R.
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      Geographic variations in the rates of operative procedures involving the shoulder, including total shoulder replacement, humeral head replacement, and rotator cuff repair.
      as well as in orthopaedic surgeons’ approaches to individual case scenarios.
      • Dunn W.R.
      • Schackman B.R.
      • Walsh C.
      • Lyman S.
      • Jones E.C.
      • Warren R.F.
      • et al.
      Variation in orthopaedic surgeons’ perceptions about the indications for rotator cuff surgery.
      As a result, the indications for rotator cuff repair are not clearly defined or accepted.
      • Oh L.S.
      • Wolf B.R.
      • Hall M.P.
      • Levy B.A.
      • Marx R.G.
      Indications for rotator cuff repair. A systematic review.
      • Wolf B.R.
      • Dunn W.R.
      • Wright R.W.
      Indications for repair of full-thickness rotator cuff tears.
      Patients who present with shoulder pain without a history of an injury and an MRI-documented rotator cuff tear present a dilemma to physicians because there are few data to help make decisions regarding appropriate treatment.
      Clearly, larger tears were once small, and progression has been documented in some patients.
      • Maman E.
      • Harris C.
      • White L.
      • Tomlinson G.
      • Shashank M.
      • Boynton E.
      Outcome of non-operative treatment of symptomatic rotator cuff tears monitored by magnetic resonance imaging.
      • Melis B.
      • DeFranco M.J.
      • Chuinard C.
      • Walch G.
      Natural history of fatty infiltration and atrophy of the supraspinatus muscle in rotator cuff tears.
      • Melis B.
      • Wall B.
      • Walch G.
      Natural history of infraspinatus fatty infiltration in rotator cuff tears.
      • Yamaguchi K.
      • Tetro A.M.
      • Blam O.
      • Evanoff B.A.
      • Teefey S.A.
      • Middleton W.D.
      Natural history of asymptomatic rotator cuff tears: a longitudinal analysis of asymptomatic tears detected sonographically.
      • Zingg P.O.
      • Jost B.
      • Sukthankar A.
      • Buhler M.
      • Pfirrmann C.W.A.
      • Gerber C.
      Clinical and structural outcomes of nonoperative management of massive rotator cuff tears.
      It is known that asymptomatic tears may become symptomatic
      • Yamaguchi K.
      • Tetro A.M.
      • Blam O.
      • Evanoff B.A.
      • Teefey S.A.
      • Middleton W.D.
      Natural history of asymptomatic rotator cuff tears: a longitudinal analysis of asymptomatic tears detected sonographically.
      and that in patients with bilateral rotator cuff tears where one is symptomatic and the other is not, the symptomatic tears is typically larger.
      • Yamaguchi K.
      • Ditsios K.
      • Middleton W.D.
      • Hildebolt C.F.
      • Galatz L.M.
      • Teefey S.A.
      The demographic and morphological features of rotator cuff disease. A comparison of asymptomatic and symptomatic shoulders.
      This information would lead some surgeons to recommend surgery for all patients with rotator cuff tears. However, it is also known that progression can occur without the development of symptoms.
      • Yamaguchi K.
      • Tetro A.M.
      • Blam O.
      • Evanoff B.A.
      • Teefey S.A.
      • Middleton W.D.
      Natural history of asymptomatic rotator cuff tears: a longitudinal analysis of asymptomatic tears detected sonographically.
      Unfortunately, the literature does not identify the risks for progression of rotator cuff tear size or for predicting in which patients symptoms will develop.
      One randomized controlled trial compared rotator cuff repair with nonoperative treatment in patients with rotator cuff tears less than 3 cm in size.
      • Moosmayer S.
      • Lund G.
      • Seljom U.
      • Svege I.
      • Hennig T.
      • Tariq R.
      • et al.
      Comparison between surgery and physiotherapy in the treatment of small and medium-sized tears of the rotator cuff; a randomized controlled study of 103 patients with one-year follow up.
      In this study, the Constant scores at 12 months were significantly better in the surgery group (76.8 vs 66.8); however, of the 51 patients randomized to their therapy group, only 9 patients (17%) had failure and elected to have surgery. These data parallel the findings in our study and suggest that surgical treatment may not be necessary for many individuals.
      Prevalence data support this contention. On the basis of multiple cadaveric and MRI studies, a conservative estimate would suggest that 10% of Americans aged over 60 years have full-thickness rotator cuff tears.
      • Reilly P.
      • Macleod I.
      • Macfarlane R.
      • Windley J.
      • Emery R.J.H.
      Dead men and radiologists don’t lie: a review of cadaver and radiologic studies of rotator cuff tear prevalence.
      This would mean that nearly 6 million Americans have full-thickness rotator cuff tears. A generous estimate of the number of rotator cuff repairs performed each year in the United States is 250,000,
      • McCormick H.
      ArthroCare closes opus medical acquisition.
      which would mean that fewer than 5% of all of the full-thickness rotator cuff tears that exist in the US population are treated surgically.
      Multiple case series report success rates with nonoperative treatment to range between 59% and 85%; however, these studies are subject to selection bias and are retrospective in design, and many of these studies include only those patients with massive tears in whom surgery cannot be performed.
      • Ainsworth R.
      • Lewis J.S.
      Exercise therapy for the conservative management of full thickness tears of the rotator cuff: a systematic review.
      One prospective cohort study of 103 shoulders with rotator cuff tears treated without surgery showed lasting pain relief 13 years after diagnosis, and 72% of patients had no disturbance in activities of daily living
      • Kijima H.
      • Minagawa H.
      • Nishi T.
      • Kikuchi K.
      • Shimada Y.
      Long-term follow up of rotator cuff tear treated conservatively.
      ; however, those who had pain or functional loss tended to be younger at the time of diagnosis.
      Our prospectively collected data enrolling all patients with atraumatic rotator cuff tears suggest that physical therapy is highly effective at improving symptoms. On the basis of the prevalence data described earlier, the majority of patients with rotator cuff tears either are asymptomatic or have minimal symptoms, and it seems that the physical therapy program used in this protocol may bring patients to a relatively asymptomatic state.
      This research has raised many questions. First, it would be important to know exactly what the risk factors are that would predict progression of known rotator tears or development of symptoms. Equally important would be information that allows us to predict which repaired tears are likely to fail. This information would certainly help surgeons and patients make informed decisions regarding surgery.
      The nature of the patient’s symptoms and the patient’s expectations of treatment are important to appreciate when one is making decisions regarding surgery for rotator cuff tears. Most patients will present to the physician with pain as a chief complaint. Preliminary analysis of data from this study have shown that the severity of the rotator cuff tear has no correlation with the severity of pain

      Dunn WR, An A, Khazzam MS, Baumgarten KM, Bishop JY, Brophy RH, et al. Symptoms of pain do not correlate with rotator cuff tear severity. Presented at the American Academy of Orthopaedic Surgeons Annual Meeting, San Diego, CA, February 16, 2011.

      or the duration of symptoms.

      Unruh KP, Dunn WR, Kuhn JE, Sanders R, An AQ, Baumgarten KM, et al. Relationship between duration of rotator cuff tear symptoms and patient presentation features. Presented at the American Shoulder and Elbow Surgeons Open Meeting, February 11, 2012, San Francisco, CA.

      Interestingly, patients with failed rotator cuff repairs report outcome scores that are not significantly different from scores in patients whose repairs have healed,
      • DeFranco M.J.
      • Bershadsky B.
      • Ciccone J.
      • Yum J.K.
      • Iannotti J.P.
      Functional outcome of arthroscopic rotator cuff repairs: a correlation of anatomic and clinical results.
      • Jost B.
      • Pfirmann C.W.
      • Gerber C.
      Clinical outcome after structural failure of rotator cuff repairs.
      • Klepps S.
      • Bishop J.
      • Lin J.
      • Cahlon O.
      • Strauss A.
      • Hayes P.
      • et al.
      Prospective evaluation of the effect of rotator cuff integrity on the outcome of open rotator cuff repairs.
      • Ko S.H.
      • Friedman D.
      • Seo D.K.
      • Jun H.M.
      • Warner J.J.
      A prospective therapeutic comparison of simple suture repairs to massive cuff stitch repairs for treatment of small- and medium-sized rotator cuff tears.
      • Oh J.H.
      • Kim S.H.
      • Ji H.M.
      • Jo K.H.
      • Bin S.W.
      • Gong H.S.
      Prognostic factors affecting anatomic outcome of rotator cuff repair and correlation with functional outcome.
      • Slabaugh M.A.
      • Nho S.J.
      • Grumet R.C.
      • Wilson J.B.
      • Seroyer S.T.
      • Frank R.M.
      • et al.
      Does the literature confirm superior clinical results in radiographically healed rotator cuffs after rotator cuff repair?.
      unless the outcome score includes a large component for strength (eg, Constant score), in which case healed repairs have better scores.
      • Moosmayer S.
      • Lund G.
      • Seljom U.
      • Svege I.
      • Hennig T.
      • Tariq R.
      • et al.
      Comparison between surgery and physiotherapy in the treatment of small and medium-sized tears of the rotator cuff; a randomized controlled study of 103 patients with one-year follow up.
      • Slabaugh M.A.
      • Nho S.J.
      • Grumet R.C.
      • Wilson J.B.
      • Seroyer S.T.
      • Frank R.M.
      • et al.
      Does the literature confirm superior clinical results in radiographically healed rotator cuffs after rotator cuff repair?.
      The physical therapy program in this study was highly effective in alleviating patient symptoms despite the fact that patients continued to have tears in the rotator cuff. This leads one to believe that pain may not be the best indication for rotator cuff repair. Weakness or loss of function may be a better indication for surgery than pain. Further analysis of this cohort will be undertaken to identify those features that distinguish patients who decided to have surgery from those who did not. These data should provide some insight into the features that predict failure of nonoperative treatment and should help clarify indications for surgery.

      Conclusions

      This large, multicenter prospective cohort study has shown that a specific physical therapy protocol can be very effective in treating symptoms in patients with atraumatic full-thickness rotator cuff tears. If failure is defined as patients electing to have surgery, then this program is successful in approximately 75% of patients at 2-year follow-up. Interestingly, much of the physical therapy was done at home, with patients averaging slightly more than 1 physical therapy visit per week. Physical therapy is not ideal for all patients, and some will elect to undergo surgery early. Others may be at risk for symptom or rotator cuff tear progression. Decisions regarding surgery should be made individually with each patient but should include information that the physical therapy program used in this study is highly effective in alleviating symptoms.

      Acknowledgments

      The authors acknowledge the following research personnel from their respective institutions: Brooke Rode, BA, at Vanderbilt University; Linda Burnworth, Amanda Haas, MA, and Deb Hanson at Washington University in St Louis; Carla Britton, PhD, at the University of Iowa; Samuel Chu, Jessica Ryu, Patrick Grimm, Kaitlyn Lillemoe, and Brian Boyle at the Hospital for Special Surgery; Angela Pedroza, BS, at The Ohio State University; May Shishido at the University of California–San Francisco; Kari Caspers at the Orthopaedic Institute; and Lori Sharp, PA-C, and Jeff Jarnigan, PA-C, at Knoxville Orthopaedic Clinic.

      Disclaimer

      Brian G. Holloway reports that he has received royalties, stock, and consultant fees from Tornier for work related to the subject of this article.
      Grant L. Jones reports that he has received research grants from Biomet and Genzyme for work related to the subject of this article.
      The other authors, their immediate families, and any research foundations 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.
      This work was supported by the following funding agencies: Arthrex (unrestricted research gift); NFL Charities (medical research grant); National Institutes of Health (grant No. 5K23-AR05392-05 from the National Institute of Arthritis and Musculoskeletal and Skin Diseases ); American Orthopaedic Society for Sports Medicine Career Development Award ; and Pfizer (Scholars Grant in Clinical Epidemiology).

      Supplementary data

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