Effectiveness of Standardized Physical Therapy Exercises for Patients With Difficulty Returning to Usual Activities After Decompression Surgery for Subacromial Impingement Syndrome
Effectiveness of Standardized Physical Therapy Exercises for Patients With Difficulty Returning to Usual Activities After Decompression Surgery for Subacromial Impingement Syndrome: Randomized Controlled Trial David Høyrup Christiansen, Poul Frost, Deborah Falla, Jens Peder Haahr, Lars Henrik Frich, Linda Christie Andrea, Susanne Wulff Svendsen
Background. Little is known about the effectiveness of exercise programs after decom- pression surgery for subacromial impingement syndrome. For patients with difficulty returning to usual activities, special efforts may be needed to improve shoulder function.
Objective. The purpose of this study was to evaluate the effectiveness at 3 and 12 months of a standardized physical therapy exercise intervention compared with usual care in patients with difficulty returning to usual activities after subacromial decompression surgery.
Design. A multicenter randomized controlled trial was conducted.
Setting. The study was conducted in 6 public departments of orthopedic surgery, 2 departments of occupational medicine, and 2 physical therapy training centers in Central Denmark Region.
Patients. One hundred twenty-six patients reporting difficulty returning to usual activities at the postoperative clinical follow-up 8 to 12 weeks after subacromial decompression surgery participated.
Intervention. A standardized exercise program consisting of physical therapist–super- vised individual training sessions and home training was used.
Outcome Measures. The primary outcome measure was the Oxford Shoulder Score. Secondary outcome measures were the Constant Score and the Fear-Avoidance Beliefs Questionnaire.
Results. At 3 and 12 months, follow-up data were obtained for 92% and 83% of the patients, respectively. Intention-to-treat analyses suggested a between-group difference on the Oxford Shoulder Score favoring the exercise group at 3 months, with an adjusted mean difference of 2.0 (95% confidence interval��0.5, 4.6), and at 12 months, with an adjusted mean difference of 5.8 (95% confidence interval�2.8, 8.9). Significantly larger improvements for the exercise group were observed for most secondary and supplementary outcome measures.
Limitations. The nature of the exercise intervention did not allow blinding of patients and care providers.
Conclusion. The standardized physical therapy exercise intervention resulted in statisti- cally significant and clinically relevant improvement in shoulder pain and function at 12 months compared with usual care.
D.H. Christiansen, PT, PhD, Department of Occupational Medicine, Danish Ramazzini Cen- tre, Regional Hospital West Jutland–University Research Clinic, Gl Landevej 61, 7400 Herning, Denmark. Address all correspon- dence to Dr Christiansen at: David.Christiansen@vest.rm.dk.
P. Frost, MD, PhD, Department of Occupational Medicine, Danish Ramazzini Centre, Aarhus Hospi- tal, Aarhus University Hospital, Aarhus, Denmark.
D. Falla, PT, PhD, School of Sport, Exercise and Rehabilitation Sci- ences, College of Life and Environ- mental Sciences, University of Birmingham, Birmingham, United Kingdom, and Pain Clinic, Center for Anesthesiology, Emergency and Intensive Care Medicine, Uni- versity Hospital Göttingen, Göttin- gen, Germany.
J.P. Haahr, MD, MPH, Department of Occupational Medicine, Danish Ramazzini Centre, Regional Hospital West Jutland–University Research Clinic.
L.H. Frich, MD, PhD, Orthopedic Department, Odense University Hospital, Odense, Denmark.
L.C. Andrea, MD, Department of Occupational Medicine, Danish Ramazzini Centre, Regional Hospital West Jutland–University Research Clinic.
S.W. Svendsen, MD, PhD, Department of Occupational Medicine, Danish Ramazzini Cen- tre, Regional Hospital West Jut- land–University Research Clinic.
Author information continues on next page.
Research Report
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June 2016 Volume 96 Number 6 Physical Therapy f 787
Subacromial impingement syn-drome (SIS) is the most commonupper extremity musculoskeletal disorder in the working population.1
Initial treatment of SIS is nonsurgical and includes rest, nonsteroidal anti- inflammatory drugs, corticosteroid injec- tions, and different modalities of physical therapy. Surgical intervention, in the form of arthroscopic subacromial decompression, is usually reserved for patients who do not respond sufficiently to initial nonsurgical treatment.2 Data suggest 2- to 8-fold increases in surgery rates since the late 1990s,3–6 with prob- abilities of success varying between 60% and 84%.7–9
Physical therapist–supervised exercises and instructions in self-training are often used to restore shoulder function after surgery for SIS.10 There is no consensus about the most appropriate postopera- tive exercise strategy, and little is known about the effectiveness of different exer- cise programs following subacromial decompression.11–14 It is unknown whether physical therapist–supervised exercises should be offered to all patients or reserved for those with more persistent symptoms. Special efforts may be needed to facilitate return to normal function for patients who have failed to return to usual activities 8 to 12 weeks after surgery. The aim of this study was to compare the effectiveness of a stan- dardized physical therapy exercise inter- vention with usual care in patients with difficulty returning to usual activities after subacromial decompression sur- gery for SIS. We hypothesized that stan- dardized physical therapy exercises would yield superior results with respect to improvement in shoulder pain and function compared with usual care.
Method Design Overview The study was conducted within the framework of the Shoulder Intervention Project, which included a pragmatic multicenter randomized controlled trial to evaluate the effectiveness of physical therapy exercises and occupational med- ical assistance in reducing shoulder pain and improving function and in reducing postoperative work disability after arthroscopic subacromial decompres-
sion surgery for SIS.15 The trial had 4 randomization arms: (1) physical therapy exercises, (2) occupational medical assis- tance, (3) physical therapy exercises and occupational medical assistance, and (4) usual care. Patients were randomized to 1 of the 4 arms if they were employed in paid work for at least 25 hours per week. Patients who did not meet the 25 hours’ employment criterion were randomly assigned to only 1 of the 2 arms without occupational medical assistance (ie, physical therapy exercises or usual care). Accordingly, we planned to use a parallel group design to evaluate the effective- ness of the physical therapy interven- tion, treating occupational medical assis- tance as a cointervention; all patients (with and without paid work) could be included in these analyses. For patients who were employed in paid work, the effectiveness of the occupational inter- vention will be evaluated in a separate publication, with primary outcomes being sickness absence percentage at 3 months and transfer income percentage at 12 months.15
Setting and Participants Patients were recruited from the 6 public departments of orthopedic surgery in Central Denmark Region over a 3-year period until December 31, 2013. At the postoperative clinical follow-up 8 to 12 weeks after surgery, patients aged �18 to �63 years and living in the region were assessed for eligibility if they had undergone arthroscopic subacromial decompression surgery (surgical code KNBH51, KNBH91, KNBG09, KNBL39, or KNBM79 according to the Danish ver- sion of the Nordic Medico-Statistical Committee Classification of Surgical Procedures16) under a main diagnosis of SIS or acromioclavicular osteoarthritis (International Classification of Dis- eases, 10th revision17: M75.1–M75.8 or M19). Exclusion criteria were full- thickness rotator cuff tear, traumatic lesion, rheumatoid arthritis, frozen shoulder, severe fibromyalgia, glenohu- meral osteoarthritis, and insufficient Danish language skills. Until April 2012, patients also were excluded if they had previous shoulder surgery or diabetes, if they were not employed in paid work for at least 25 hours per week, and if they were not full-time sick-listed; these
[Christiansen DH, Frost P, Falla D, et al. Effec- tiveness of standardized physical therapy exercises for patients with difficulty return- ing to usual activities after decompression surgery for subacromial impingement syn- drome: randomized controlled trial. Phys Ther. 2016;96:787–796.]
© 2016 American Physical Therapy Association
Published Ahead of Print: February 25, 2016
Accepted: February 15, 2016 Submitted: November 27, 2015
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exclusion criteria were abandoned due to slow recruitment.15 Eligible patients were provided with information on the Shoulder Intervention Project. Via a tele- phone interview, patients who con- sented to be contacted were invited to participate if they reported at least slight shoulder problems doing usual activities, when assessed on a 5-level scale (no problems, slight problems, moderate problems, severe problems, and unable).18 Written informed consent was given by all patients who participated in the trial. Within 1 week after the postop- erative clinical follow-up, a baseline assessment was performed in 1 of the 2 departments of occupational medicine in Central Denmark Region (east or west center).
Randomization and Interventions Randomization took place after baseline data collection and was performed by a research secretary, who assigned partic- ipants to interventions. Computer- generated randomization (1:1 ratio) was used, with stratification by the surgical department and blocking within strata using randomly permuted block sizes of 12, 8, and 4.
Physical therapy exercise inter- vention. The intervention consisted of a standardized exercise program, which was conducted in 1 of 2 municipal training centers. The development of the intervention and details of the program have been presented elsewhere.19 Addi- tionally, a detailed manual for physical therapists and a patient pamphlet with home training instructions and a training diary are available.20 The intervention was delivered as a combination of phys- ical therapist–supervised individual train- ing sessions and home training for 8 weeks followed by home training for an additional 4 weeks. The supervised train- ing sessions lasted up to 60 minutes each. All training sessions started with aerobic exercise on a stationary bicycle, and additional manual treatment was offered in case of restricted range of motion or pain. The shoulder-specific training consisted of a core set of 7 exer- cises, each with 3 performance levels: (1) exercises focusing on activation of the scapula and rotator cuff muscles, (2)
progression in terms of starting position and range of motion, and (3) exercises in full range of motion and with higher demands on coordination and core sta- bility. Patients were scheduled to receive a minimum of 8 and a maximum of 15 training sessions (including the initial and final clinical evaluations) during the first 8 weeks. During the first 4 of these weeks, the training was typically distrib- uted with supervised sessions 2 times a week plus home training at least twice a week. During the next 4 weeks, the fre- quency of supervised sessions could be reduced and the frequency of home training increased, depending on the patient’s individual need for supervision and ability to perform the exercises. This was done to gradually make the patients more confident in handling the training themselves. Patients were informed that, in general, shoulder activities are not harmful and may lead to reduced symp- toms and improved function. Patients also were advised to be physically active at moderate-to-high intensity for at least 30 minutes at least 3 times a week,21 as physical activity is generally recom- mended in the management of musculo- skeletal pain.22,23
Each patient kept a diary for home train- ing and physical activity. The physical therapists registered any adverse events, their assessment of deviations from the exercise program, and the patient’s over- all adherence to the intervention in the manual. The latter 2 assessments were made using a 5-point scale ranging from “to a very great extent” to “to a very little extent” and from “very good” to “very poor,” respectively. The 5 intervention physical therapists had an average of 10 years (range�6–14) of experience in the management of patients with shoulder disorders and treated an average of 12 (range�7–15) patients with shoulder complaints per week. They had com- pleted 2 to 5 postgraduate courses on the treatment of shoulder disorders. Throughout the project period, a uni- form application of the intervention was supported by center-specific team meet- ings, with the presence of an investigator every second month.
Usual care. Patients in the usual care group received no intervention as part of
the study, but they were advised to con- tinue treatment as directed by the hospi- tal. At 3 months, questionnaire data were collected on the number of treatments, if any, received by physical therapists since baseline and the type of treatment received (shoulder-specific exercise instructions or supervised exercise therapy, manual therapy, or other modalities).
Cointerventions. The subgroup of patients who were employed in paid work for at least 25 hours per week could be randomized to occupational medical assistance provided by an occu- pational physician. This intervention included a standardized assessment of work instability (ie, imbalance between functional capabilities and job demands to an extent where job retention is threatened) and construction of a 3-month action plan to promote job retention. At 6 weeks, progress was eval- uated by telephone, and at the 3-month follow-up, patients were seen for a final consultation and workplace-oriented advice. Details of the occupational med- ical assistance are provided elsewhere.15
Information on treatment received from physicians, chiropractors, or other health care providers was obtained by questionnaire at the 3-month follow-up.
Outcome Measures and Follow-up The patients were assessed at baseline (8–12 weeks postsurgery) and at 3- and 12-month follow-ups. At baseline and 3 months, the patients completed a ques- tionnaire prior to a standardized shoul- der examination and physical testing. At 12 months, data were collected using a mailed questionnaire. The primary out- come measure was the validated Oxford Shoulder Score,24–28 which contains 12 items related to pain and activities of daily living summarized into a total score of 0 to 48, with 48 being the best out- come. Secondary outcome measures were the Constant Score (evaluated only at baseline and at 3 months) and the Fear-Avoidance Beliefs Questionnaire physical activity scale. The Constant Score is a 100-point system for functional assessment of the shoulder, which com- bines subjective parameters (pain and activities of daily living) and objective
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parameters (range of motion and strength), with a score of 100 points being the best outcome.29,30 The assess- ment of Constant Score was performed according to a standardized test proto- col,31 which has demonstrated accept- able intrarater and interrater reliability.32
Shoulder strength was measured with an IsoForceControl dynamometer (Medical Device Solutions AG, Oberburg, Switzer- land). The Fear-Avoidance Beliefs Ques- tionnaire physical activity scale was used in a version modified to the shoulder, yielding a 0- to 24-point score, with higher scores reflecting a higher ten- dency for fear-avoidance beliefs.33,34
According to the fear-avoidance model, pain-related fear may cause patients to avoid physical activities in order to reduce pain, and if exaggerated, this reaction pattern may increase pain and lead to disability.35 Reduction of fear avoidance might be part of the interven- tion’s mechanism of action on shoulder pain and function.36,37
We included 5 supplementary outcome measures. Health-related quality of life was measured at 3 and 12 months with the EQ-5D-3L questionnaire,38 and the measurements combined with utility val- ues derived from a general population sample to calculate an index score rang- ing from �0.6 to 1.0, with higher scores representing a better health state.39 At 3 months, the following clinical outcome measures were evaluated: maximum oxygen uptake, positive pain provoca- tion signs, and scapula dyskinesis. Maxi- mum oxygen uptake (mL O2/min/kg) was evaluated using the Astrand and Rhyming Cycle Ergometer Test (Monark 928E Pro VO2 bike, Monark Exercise AB, Vansbro, Sweden).40,41 This outcome measure was included, in part, as an incentive for the patients to follow the advice on general physical activity and because increased fitness might be part of the intervention’s mechanism of action on shoulder pain. Positive pain provocation signs were evaluated and defined as �2 positive tests out of the following: Hawkins test, modified Hawk- ins test, painful arc test, and Jobe test.42
Scapular dyskinesis was evaluated and defined in terms of a positive Scapula Dyskinesis Test with obvious signs of altered scapular movement judged by
visual inspection combined with a posi- tive Scapula Assistance Test or a positive Scapula Retraction Test showing an effect of manual correction on dysfunc- tion and symptoms.42,43 This outcome measure was included because it was thought that scapular dyskinesis might be associated with postoperative pain and disability and that reduction of altered mobility patterns might be part of the intervention’s mechanism of action. Finally, at both 3 and 12 months, the Patients’ Global Impression of Change scale scores were evaluated to assess the patients’ global impression of change in their shoulder condition. This score was assessed on a 7-point scale ranging from “much better” to “much worse.” Clinical examinations were performed by a blinded assessor, but blinding of the patients and those who provided the interventions was not possible. At 3 months, the allocation of each patient was estimated by the assessor so that the success of blinding of the assessor could be evaluated.
Data Analysis With a power of 0.8, a significance level of .05, and a total of 65 patients who received the physical therapy interven- tion and 65 patients who did not receive it, a minimal mean difference of 2.4 points in the Oxford Shoulder Score could be detected at 12 months when assuming a standard deviation of 9.0 points,25 a correlation between baseline and follow-up scores of 0.5, and a 10% dropout rate.
Main analyses were performed in accor- dance with the intention-to-treat princi- ple. Supplementary per-protocol analy- ses (ie, analyses restricted to patients who received the intervention as intended) also were performed. The effectiveness of the physical therapy intervention was estimated as mean dif- ferences between groups using linear regression models for continuous out- comes and as odds ratios using nominal logistic regression for binary outcomes and ordered logistic regression for the categorical outcome measure Patients’ Global Impression of Change scale, where the 7 original response categories were collapsed to 4. Models included the occupational intervention (yes/no/
irrelevant), center (east/west), and respective baseline values where appli- cable. The robustness of the results was investigated by sensitivity analyses (ie, assigning higher and lower scores in patients without follow-up data). For comparison with previous literature on exercise management, standardized effect size was calculated for the primary outcome (ie, the unadjusted mean differ- ence between the groups divided by the pooled standard deviation at baseline). The minimal clinically important change (MCIC) for the Oxford Shoulder Score has been estimated to be 6 points44,45; the number of patients who clinically improved and the number needed to treat were calculated based on this pre- viously reported threshold. Stata version 13 (StataCorp LP, College Station, Texas) was used.
Role of the Funding Source The study was a researcher-initiated study, primarily funded by The Danish Agency for Science, Technology and Innovation (grant number 09-066985), with co-funding from the Danish Ramazzini Centre.
Results Participants The Figure shows the flow of partici- pants from assessment of eligibility at the postoperative clinical follow-up 8 to 12 weeks after surgery and throughout the trial. Patients who declined to participate in the study did not differ from those who participated with respect to age, sex, and employment status. A total of 126 patients were randomized. Patients in the 2 comparison groups were bal- anced with respect to baseline character- istics, allocation to occupational medical assistance (Tab. 1), and baseline out- come scores (Tab. 2), except for the EQ-5D-3L index, maximum oxygen uptake, and the prevalence of patients with positive pain provocation signs.
Missing and Incomplete Data At baseline, 1 patient left 2 questions unanswered on the Oxford Shoulder Score, and 2 patients left 1 and 2 ques- tions unanswered, respectively, on the Fear-Avoidance Beliefs Questionnaire physical activity scale. This was reme- died by replacing the missing question
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by the mean value of their other responses on the scale (single mean imputation). Two patients, one who left all items on the Fear-Avoidance Beliefs Questionnaire physical activity scale unanswered at baseline and one who failed to answer the EQ-5D-3L question- naire at 3 months, were left out of the
analysis of these outcomes. For 9 patients (6 at baseline and 3 at 3-month follow-up), the maximum oxygen uptake could not be estimated due to medica- tion use, inability to perform the cycle ergometer test with enough resistance, or other health problems. Scapular dys- kinesis could not be assessed in 11
patients at baseline (Tab. 2) and in 2 patients at 3 months (one in each group), as they were not able to perform active abduction or flexion �90 degrees because of pain. Missing clinical test val- ues were not replaced. At 12 months, scores were calculated by the use of sin- gle mean imputation in one patient who left one question unanswered on the Oxford Shoulder Score and in one patient who left one question unan- swered in the Fear-Avoidance Beliefs Questionnaire physical activity scale.
Treatment Effect At 3 and 12 months, 92% and 83% of the patients, respectively, were followed up. At 3 months, intention-to-treat analysis showed a nonsignificant difference in favor of the physical therapy exercise intervention with regard to the Oxford Shoulder Score (Tab. 2). Analyses of sec- ondary and supplementary outcome measures significantly favored the exer- cise group with respect to the Constant Score, scapular dyskinesis, maximum oxygen uptake, and Patients’ Global Impression of Change scale score. At 12 months, significantly larger improve- ments were found in the physical ther- apy exercise group with respect to the Oxford Shoulder Score, the Fear- Avoidance Beliefs Questionnaire physi- cal activity scale, the EQ-5D-3L index, and the Patients’ Global Impression of Change scale (Tab. 2). The standardized effect size for the Oxford Shoulder Score was 0.74 (95% confidence interval [CI]�0.30, 1.17). More patients in the exercise group (69%) than in the usual care group (51%) improved �6 points in their Oxford Shoulder Score; the adjusted odds ratio was 2.4 (95% CI�1.0, 5.6), with a number needed to treat of 5.0 (95% CI�2.6, 48.6). When per- protocol analyses were performed, the differences in favor of the physical ther- apy exercise intervention at 3 months also reached statistical significance for the Oxford Shoulder Score, with an adjusted mean difference of 2.8 (95% CI�0.2, 5.4), and for the Fear-Avoidance Beliefs Questionnaire physical activity scale, with an adjusted mean difference of �2.4 (95% CI��4.5, �0.4).
Table 1. Baseline Characteristics of Participants According to Random Allocation to Usual Care or Physical Therapy Exercise Groupsa
Characteristic Usual Care
Group (n�66) Physical Therapy
Exercise Group (n�60)
Female 42 (63.6) 40 (66.7)
Age (y), X (SD) 49.0 (7.1) 48.1 (7.9)
Body mass index (kg/m2), X (SD) 29.8 (7.5) 28.2 (5.0)
Bilateral shoulder painb 30 (46.2) 22 (36.7)
Dominant shoulder affected 45 (68.2) 37 (61.7)
Employment status
Employed in paid work �25 h/wk 37 (56.1) 34 (56.3)
Self-employed 3 (4.6) 3 (5.0)
Unemployed 16 (24.2) 15 (25.0)
Early retirement/flexible job/disability pension 8 (12.1) 7 (11.7)
Student/on leave 2 (3.0) 1 (1.7)
Sick leave because of shoulder symptomsc 42 (63.6) 38 (63.3)
Use of analgesics within last 4 wk
Paracetamol/NSAIDs 52 (78.8) 43 (71.7)
Opioids 19 (28.8) 9 (15.0)
Postoperative exercises in first 8–12 wk
No instruction or handouts 10 (15.2) 10 (16.7)
Instruction by physical therapist in self-training 26 (39.4) 18 (30.0)
Physical therapist–supervised exercises 30 (45.5) 32 (53.3)
Number of sessions with a physical therapist, median (IQR)
1 (1–9) 3 (1–7)
Additional treatment
None 51 (77.3) 46 (76.7)
Steroid injection 6 (9.1) 4 (6.7)
Spinal manipulation/mobilization 5 (7.6) 8 (13.3)
Massage/acupuncture 4 (6.1) 2 (3.3)
Allocation to occupational medical assistanced
Occupational medical assistance 20 (30.3) 22 (36.7)
Usual care 17 (25.8) 12 (20.0)
Irrelevant 29 (43.9) 26 (43.3)
a Values are numbers (percentages) unless otherwise stated. IQR�interquartile range, NSAIDs�nonsteroidal anti-inflammatory drugs. b Data missing for one patient. c Patients sick-listed from paid work, self-employment, or unemployment. d Patients employed in paid work for at least 25 h/wk were randomly allocated to occupational medical assistance (with or without physical therapy exercises) or usual care (with or without physical therapy exercises); this was irrelevant for remaining patients.
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Table 2. Effectiveness of Physical Therapy Exercises Compared With Usual Care With Respect to Primary, Secondary, and Supplementary Outcome Measuresa
Variables Usual Care
Group Physical Therapy Exercise Group
Intention-to-Treat Treatment Effectb
Continuous outcomes, n, X, (SD) Mean difference (95% CI)
Oxford Shoulder Scorec
Baseline 66 29.1 (8.0) 60 31.0 (6.4)
3 mo 61 35.0 (9.5) 55 37.7 (7.9) 2.0 (�0.5, 4.6)
12 mo 53 34.2 (11.3) 51 41.2 (7.1) 5.8 (2.8, 8.9)
Constant Scored
Baseline 66 52.7 (13.5) 60 54.1 (15.0)
3 mo 59 63.9 (19.1) 54 70.4 (17.5) 6.7 (1.2, 12.2)
Fear-Avoidance Beliefs Questionnaire physical activity scale scoree
Baseline 65 12.6 (6.0) 60 11.3 (6.4)
3 mo 61 10.1 (7.0) 55 7.8 (6.5) �1.8 (�3.8, 0.3)
12 mo 53 10.2 (7.4) 51 6.0 (5.9) �3.3 (�5.6, �0.9)
EQ-5D-3L index scoref
Baseline 66 0.67 (0.16) 60 0.72 (0.11)
3 mo 60 0.72 (0.21) 55 0.77 (0.14) 0.04 (�0.02, 0.10)
12 mo 53 0.71 (0.24) 51 0.83 (0.14) 0.09 (0.02, 0.17)
Maximum oxygen uptake (mL O2/min/kg)
Baseline 61 26.3 (8.3) 59 29.3 (8.3)
3 mo 55 27.1 (7.6) 51 32.3 (9.6) 2.1 (0.1, 4.1)
Binary outcomes, n, X, (%) OR (95% CI)
Positive pain provocation signsg
Baseline 66 53 (80.3) 60 38 (63.3)
3 mo 55 36 (61.0) 54 23 (42.6) 0.6 (0.3, 1.3)
Scapular dyskinesish
Baseline 59 18 (30.5) 56 16 (28.6)
3 mo 52 13 (25.0) 50 4 (8.0) 0.2 (0.1, 0.8)i
Categorical outcome, n (%)
Patients’ Global Impression of Change scale score
3 mo
Worse 7 (11.5) 3 (5.5)
No change 21 (34.4) 19 (34.6)
Better 20 (32.8) 9 (16.4)
Much better 13 (21.3) 24 (43.6) 2.1 (1.0, 4.1)j
12 mo
Worse 10 (19.9) 3 (5.9)
No change 17 (32.1) 15 (29.4)
Better 12 (22.6) 10 (19.6)
Much better 14 (26.4) 23 (45.1) 2.2 (1.1, 4.6)j
a CI�confidence interval, OR�odds ratio. b Results of linear and logistic regression analyses adjusted for occupational medical assistance, center, and the respective baseline values. c Oxford Shoulder Score: 0–48. d Constant Score: 0–100. e Fear-Avoidance Beliefs Questionnaire physical activity score: 0–24. f EQ-5D-3L index score: �0.6 to 1.0. g Positive pain provocation signs defined as �2 positive of Hawkins test, modified Hawkins test, painful arc test, and Jobe test. h Scapular dyskinesis defined as a positive Scapula Dyskinesis Test (obvious signs) and a positive Scapula Assistance Test or Scapula Retraction Test. i Adjustment for occupational medical assistance and center not applicable because of few cases. j Results of ordered logistic regression analyses adjusted for occupational medical assistance and center.
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Intervention and Adherence In the east center, the number of patients treated in each municipal center and by each physical therapist was as follows: first physical therapist (n�6), second physical therapist (n�14), and third physical therapist (n�10). In the west center, one physical therapist treated all patients (n�22) (the second physical therapist substituted in only 1 or 2 ses- sions). Patients allocated to physical ther- apy exercises received a median of 12 (interquartile range�9–13) supervised training sessions. Ten patients did not receive physical therapy exercises as intended (Figure). The main reasons given by these patients were long travel- ing distance, lack of time, or a new job. Seven and 6 of the 10 patients who did not adhere provided data at 3 and 12 months, respectively.
At the final training session, 37 out of 50 patients (74%) performed at least 5 of the 7 exercises at the highest level (level C), and, on average, resistance in loaded exercises had increased by 74% (95% CI�53%, 95%). The physical therapists rated the overall patient adherence to the physical therapy exercise interven- tion as very high or high in 44 (88%) of the 50 patients who received the inter- vention. The exercise manual could only be followed to some extent for 8 patients and to a very limited extent for 1 patient. Of the 60 patients allocated to physical therapy exercises, 44 (73%) adhered. Additional manual treatment as part of the intervention was received by 34 (68%) of 50 patients who received the intervention, and the median number of sessions that included manual treatment was 2 (interquartile range�0–7). A total of 46 patients filled in their home train- ing diary; they completed their home training program an average of 2.1 (SD�0.8) times a week and performed physical activity at moderate-to-high intensity for at least 30 minutes an aver- age of 3.1 (SD�1.7) days a week over the 12-week period.
At 3 months, 48 (79%) of the 61 patients in the usual care group reported that they had received shoulder-specific exer- cise instructions or exercise therapy dur- ing the intervention period. Twenty- seven patients (44%) had received
massage/manual treatment, 7 (11%) had received acupuncture, 22 (36%) had received electrotherapy or thermother- apy, and 34 (56%) had seen a physical therapist for their shoulder problem, with a median of 8 (interquartile range�4–16) treatments received.
Cointerventions The number of patients who had con- sulted a physician for their shoulder problem during the intervention period
was significantly lower in the physical therapy exercise group than in the usual care group (5 [9%] versus 18 [30%], P�.001). No significant differences were observed between groups for the num- ber of patients who received one or more subacromial injections (6 [11%] in the physical therapy exercise group ver- sus 11 [18%] in the usual care group). Chiropractor treatment was received by 1 patient (2%) in the exercise group and 6 patients (10%) in the usual care group,
Figure. Flowchart of participants in the study. *In April 2012, when 9 patients were included in the trial, the following exclusion criteria were abandoned due to slow recruitment: previous shoulder surgery or diabetes, not employed in paid work for at least 25 hours per week, and not full-time sick-listed.
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and alternative treatment was received by 3 patients (6%) versus 7 patients (12%), with no significant differences between groups.
Adverse Events Except for muscle tenderness after train- ing and 2 cases of temporary headache in relation to training, no adverse events were noted. Two patients were reoper- ated on (one in each group) within the first 3 months (Figure).
Sensitivity Analysis and Success of Blinding Sensitivity analysis demonstrated that for the results to no longer significantly favor the intervention at 12 months, a 14-point higher mean Oxford Shoulder Score would be needed in patients who were lost to follow-up in the usual care group than in those who were lost to follow-up in the physical therapy exer- cise group. In total, 96 (85%) of 113 patients were examined by the same assessor at baseline and follow-up. The assessors correctly classified 32 patients (54%) in the usual care group and 23 patients (43%) in the physical therapy exercise group.
Discussion A standardized physical therapy exercise intervention was compared with usual care for patients with difficulty returning to usual activities after subacromial decompression surgery for SIS. At 3 months, intention-to-treat analyses showed a statistically nonsignificant dif- ference in favor of the intervention with respect to the primary outcome mea- sure, the Oxford Shoulder Score, and in per-protocol analyses, this difference was significant. At 12 months, intention- to-treat analyses demonstrated signifi- cantly larger improvement in the physi- cal therapy exercise group with respect to the Oxford Shoulder Score, fear- avoidance beliefs, health-related quality of life, and the patients’ perception of overall improvement.
The study benefited from a randomized design, high treatment adherence, vali- dated primary and secondary outcome measures, limited loss to follow-up, blinding of clinical assessors, and evalu- ation of treatment application and co-
interventions. The study had some limi- tations. The total number of 613 patients assessed for eligibility over a 3-year period was lower than expected. This lower number most likely reflected gen- eral difficulty of recruiting patients from clinical practice, rather than systematic selection, and, therefore, should not affect the generalizability of the results to patients with orthopedic conditions eval- uated for SIS. Patients could be included only if they reported at least slight prob- lems doing usual activities, and it may be questioned whether this could be defined as difficulty returning to usual activities. However, we find it unlikely that patients would agree to participate in the trial if they did not experience significant shoulder problems. The blind- ing of the outcome assessors at 3 months was successful, but the nature of exer- cise interventions did not allow blinding of patients and care providers. Informa- tion on physical therapy received by patients in the usual care group was col- lected at the 3-month follow-up. This approach might imply underestimation of the use of physical therapy, as visits to a physical therapist might have been for- gotten, but such underestimation would not explain the results in favor of the intervention. Within the first year of the trial, we widened the inclusion criteria to increase recruitment. Before that, only 9 patients had been included; therefore, the change probably only affected our results in terms of larger generalizability because the population was more repre- sentative of postoperative SIS patients of working age.
The number of missing responses to items in the questionnaires was limited, which supports the internal validity of the study findings. For the evaluation of scapular dyskinesis at 3 months, missing information was more common because the assessment could not always be per- formed due to pain provocation. Conse- quently, these results may not apply to patients with higher pain intensities and more severe limitations in shoulder func- tion. Furthermore, the validity and reli- ability of combining visual inspection and manual correction to identify scapu- lar dyskinesis have not been established. We chose to omit patients without out- come data at 3 and 12 months from the
analyses (complete case analysis).46,47
More advanced statistical approaches to handle loss to follow-up are available (ie, multiple imputation),48 but sensitivity analyses suggested that our findings were robust.
To our knowledge, this is the largest study that has evaluated physical therapy exercises after decompression surgery for SIS. Previous studies that have com- pared exercises and home training have reached contradictory results.11–14
Holmgren et al13 and Park et al14 found superior short-term effectiveness of exer- cises aiming to strengthen rotator cuff and scapular muscles compared with instructions in mobility-focused home exercises or passive modalities only (ie, electrotherapy and thermotherapy). In contrast, no short-term or long-term effects of physical therapist–supervised exercises were found compared with home training with rotator cuff strength- ening exercises11 or when more progres- sive exercise programs were compared with traditional exercise programs.12
Compared with the exercise interven- tion in previous studies, our program was initiated later because we wanted to focus our intervention efforts on patients who did not respond sufficiently to sur- gery and initial postoperative care.
We included fear-avoidance beliefs, max- imum oxygen uptake, and scapular dys- kinesis as secondary and supplementary outcome measures because they might be part of the intervention’s mechanism of action. This possibility was not contra- dicted by the reported results. Maximum oxygen uptake could further be inter- preted as a marker of adherence. Patients in the physical therapy exercise group continued to improve after the interven- tion period, whereas no further improve- ment was observed in the usual care group. Supported by a detailed patient pamphlet with home training instruc- tions, patients in the physical therapy exercise group were gradually encour- aged to handle training themselves and taught how to progress home training, maintain or improve general physical activity, and handle flare-ups, which may have contributed to this result. The observed treatment effect size for the Oxford Shoulder Score was moderate to
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large, with patients in the exercise group having 2.4 times higher odds of clinically important improvement (ie, �6 points) at 12 months, and this was found for a health condition where exercise interventions typically show small-to- moderate effects.49 At 3 months, more than half of the patients in the usual care group had received physical therapy for their shoulder problem. Nevertheless, we observed significantly greater improvement in the physical therapy exercise group across outcome measures at both 3- and 12-month follow-ups. In our opinion, this finding suggests that the standardized physical therapy exer- cise intervention could be of substantial benefit for patients with SIS who have difficulty returning to usual activities after decompression surgery.
We conducted a pragmatic trial, with the intervention delivered by general physi- cal therapists in the existing framework of public rehabilitation, and the interven- tion was compared with usual care, which often included physical therapy and shoulder-specific exercises. Conse- quently, we would expect that compara- ble results could be achieved in other physical therapy outpatient settings.
In conclusion, the results supported the effectiveness of a standardized physical therapy exercise intervention compared with usual care in patients with difficulty returning to usual activities 8 to 12 weeks after subacromial decompression surgery for SIS. Thus, the present study suggests a potential for optimizing the quality of care for patients with SIS who are surgically treated. A detailed exercise manual and a patient pamphlet allow researchers to replicate the trial and cli- nicians to apply the exercise program.
Dr Frost and Dr Svendsen conceived the project. All authors were involved in the design of the study. Assisted by Dr Frost and Dr Svendsen, Dr Christiansen developed the physical therapy intervention, performed the statistical analyses, and drafted the manu- script. All authors contributed to interpreta- tion of data and critical revision of the man- uscript. All authors read and approved the final manuscript and stand by the integrity of the entire work.
The authors thank Janne Nielsen, PT, Mette Balle Olsen, PT, Bjarne Leif Sørensen, PT, Anja Ellegaard Kjeldsen, PT, and Jesper Elia- sen, PT, who delivered the trial intervention; Anders Damgaard Møller, PT, and Klaus Dahlerup Djernes, PT, for assistance with clinical outcome assessment; and research secretaries Inge-Lis Laursen and Ann Christie Poulsen.
The study was approved by the Central Den- mark Region Committees on Biomedical Research Ethics (identification number: M-20100131) and by the Danish Data Protection Agency (journal number: 2010-41-4316).
This was a researcher-initiated study, primar- ily funded by the Danish Agency for Science, Technology and Innovation (grant number 09-066985) with co-funding from the Dan- ish Ramazzini Centre.
Trial registration: Current Controlled Trials (ISRCTN55768749).
DOI: 10.2522/ptj.20150652
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