Subacromial decompression versus diagnostic arthroscopy for shoulder impingement: a 5-year follow-up of a randomised, placebo surgery controlled clinical trial

Objectives To assess the long-term efficacy of arthroscopic subacromial decompression (ASD) by comparing it with diagnostic arthroscopy (primary comparison), a placebo surgical intervention, and with a non-operative alternative, exercise therapy (secondary comparison). Methods We conducted a multicentre, three group, randomised, controlled superiority trial. We included 210 patients aged 35–65 years, who had symptoms consistent with shoulder impingement syndrome for more than 3 months. 175 participants (83%) completed the 5 years follow-up. Patient enrolment began on 1 February 2005 and the 5-year follow-up was completed by 10 October 2018. The two primary outcomes were shoulder pain at rest and on arm activity measured with Visual Analogue Scale (VAS). Minimally important difference (MID) was set at 15. We used a mixed-model repeated measurements analysis of variance with participant as a random factor, the baseline value as a covariate and assuming a covariance structure with compound symmetry. Results In the primary intention to treat analysis (ASD vs diagnostic arthroscopy), there were no between-group differences that exceeded the MID for the primary outcomes at 5 years: the mean difference between groups (ASD minus diagnostic arthroscopy) in pain VAS were −2.0 (95% CI −8.5 to 4.6; p=0.56) at rest and −8.0 (−17.3 to 1.3; p=0.093) on arm activity. There were no between-group differences in the secondary outcomes or adverse events that exceeded the MID. In our secondary comparison (ASD vs exercise therapy), the mean differences between groups (ASD minus exercise therapy) in pain VAS were 1.0 (−5.6 to 7.6; p=0.77) at rest and −3.9 (−12.8 to 5.1; p=0.40) on arm activity. There were no significant between-group differences for the secondary outcomes or adverse events. Conclusions ASD provided no benefit over diagnostic arthroscopy (or exercise therapy) at 5 years for patients with shoulder impingement syndrome.


FIMPACT Investigators 3
Table S1 Trajectories of the primary outcomes at 3, 6, 12, 24 months and 5 years (ASD vs. DA) 5 Table S2 Trajectories of the secondary outcomes at 3, 6, 12, 24 months and 5 years (ASD vs. DA) 6 Table S3 Sensitivity analyses of the primary and secondary outcomes concerning the primary comparison (ASD vs. DA) 8 Table S4 Unblindings, treatment conversions, and reoperations 9 Table S5 Trajectories of the primary outcomes at 3, 6, 12, 24 months and 5 years (ASD vs. ET) 10 Table S6 Trajectories of the secondary outcomes at 3, 6, 12, 24 months and 5 years (ASD vs. ET) 11 Table S7 Sensitivity analyses of the primary and secondary outcomes concerning the secondary comparison (ASD vs. ET) 13 Table S8 Frequency of missing data at 3, 6, 12, 24 months and 5 years 14 Exercise Therapy (ET) Protocol Table S1 Trajectories of the primary outcomes at 3, 6, 12, 24 months and 5 years (ASD vs. DA) The table shows the mean values and between-group differences in VAS pain scores at the 3, 6, 12, 24-month and 5-year follow-ups with 95% confidence intervals. The trajectories are estimated using a mixed-effects model repeated measures (MMRM) ANOVA with adjustment for baseline imbalance. N denotes the number of subjects.

years
Pain VAS at rest 6.2 (1.6 to 10.8) 54 8.2 (3.5 to 12.8) 54 -2.0 (-8.5 to 4.6) Pain VAS on arm activity 12.4 (5.8 to 19.0) 54 20.4 (13.8 to 26.9) 54 -8.0 (-17.3 to 1. 3) The between-group differences may not exactly equal the differences in change in the scores between the ASD and DA groups because of the adjustment for baseline imbalance in the MMRM analyses. A negative between-group difference means that the participants in the ASD group reported a lower pain level.
The minor discrepancies in the results of the ASD group in this Table S2 and in the Table S6 are due to the adjustment for baseline imbalance when analysing change from baseline. The adjustment differs based on which groups are included in the model. The between-group differences may not exactly equal the differences in change in the scores between the ASD and DA groups because of the adjustment for baseline imbalance in the MMRM analyses. N/A = not applicable. For all variables, a higher score indicates a better treatment outcome. The table shows the between-group differences at the 5-year follow up. The estimated effect indicates the mean difference, ASD minus DA. The analyses were carried out using a mixed model repeated measures (MMRM) ANOVA with adjustment for baseline imbalance.  † The per protocol population is the subset of the intention to treat population who received the treatment they were randomised to and who did not receive any other treatment, i.e. the patients with a treatment conversion have been excluded (ASD: n = 59, DA: n = 54). ‡ The as treated population is defined according to the treatment the participants received, i.e. the 9 participants who originally received DA and the 14 participants who originally received ET, but due to persistent symptoms requested unblinding and subsequently received ASD, have been included in the ASD population (ASD: n = 83, DA: n = 54).  Table S5 Trajectories of the primary outcomes at 3, 6, 12, 24 months and 5 years (ASD vs. ET) The table shows the mean values and between-group differences in VAS pain scores at the 3, 6, 12, 24-month and 5year follow-ups with 95% confidence intervals. The trajectories are estimated using a mixed-effects model repeated measures (MMRM) ANOVA with adjustment for baseline imbalance. N denotes the number of subjects.

years
Pain VAS at rest 6.3 (1.5 to 11.0) 59 5.3 (0.8 to 9.8) 68 -1.0 (-5.6 to 7.6) Pain VAS on arm activity 12.6 (6.1 to 19.2) 59 16.5 (10.3 to 22.6) 68 -3.9 (-12.8 to 5.1) The between-group differences may not exactly equal the differences in change in the scores between the ASD and DA groups because of the adjustment for baseline imbalance in the MMRM analyses. A negative between-group difference means that the participants in the ASD group reported a lower pain level.
The minor discrepancies in the results of the ASD group in this Table S6 and in the Table S2 are due to the adjustment for baseline imbalance when analysing change from baseline. The adjustment differs based on which groups are included in the model.

, 12, 24 months and 5 years (ASD vs. ET)
The table shows the mean values and between-group differences in VAS pain scores at the 3, 6, 12 ,24-month and 5year follow-ups with 95% confidence intervals. The trajectories are estimated using a mixed-effects model repeated measures (MMRM) ANOVA with adjustment for baseline imbalance. N denotes the number of subjects. The between-group differences may not exactly equal the differences in change in the scores between the ASD and ET groups because of the adjustment for baseline imbalance in the MMRM analyses. N/A = not applicable. For all variables, a higher score indicates a better treatment outcome.

Table S7 Sensitivity analyses of the primary and secondary outcomes concerning the secondary comparison (ASD vs. ET)
The table shows the between-group differences at the 5-year follow-up. The estimated effect indicates the mean difference, ASD minus ET. The analyses were carried out using a mixed model repeated measures (MMRM) ANOVA with adjustment for baseline imbalance.

Variable
FAS Estimated effect (95% CI)* P value Per protocol Estimated effect (95% CI) † P value As treated Estimated effect (95% CI) ‡ P value Pain VAS at rest 1.0 (-5.6 to 7.6) 0.77 0.2 (-6.5 to 6.9) 0.96 -1.5 (-8.2 to 5.1) 0.65 Pain VAS at activity -3.9 (-12.8 to 5.1) 0.40 -3.6 (-12.9 to 5.7) 0.45 -3. † The per protocol population is the subset of the full analysis set population who received the treatment they were randomised to and who did not receive any other treatment, i.e. the patients with a treatment conversion have been excluded (ASD: n = 59, ET: n = 56). ‡ The as treated population is defined according to the treatment the participants received, i.e., the 9 participants who originally received DA and the 15 participants who originally received ET, but due to persistent symptoms requested unblinding and subsequently received ASD, have been included in the ASD population (ASD: n = 83, ET: n = 56).  The n values denote the number of participants allocated to each treatment group. The frequencies include both missing data and withdrawn subjects. Sit. Place your hand on the front of the opposite shoulder. Feel your shoulder with your fingers making sure that the shoulder does not come forward. Move your shoulder gently 1 cm back and 2 cm up. Later on, exercise is done without palpation or visual confirmation of movement.
Sit. Place your hand on the front of the opposite shoulder. Feel your shoulder with your fingers. Move your shoulder gently 1 cm forward and 2 up from resting position. Later on, exercise is done without palpation or visual confirmation of movement.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Lying on your back with elbows straight. Use one arm to lift the other arm up keeping it as close to the ear as possible.
Repeat 10 times. Lying on your back with elbows against your body and at a right angle. Hold a stick in your hands. Move the stick sideways thus pushing the arm to be exercised outwards.
Stand with arms behind your back. Grasp the wrist of the arm you want to exercise. Slide your hands up the back.
Repeat 10 times. Stand sideways against a wall with your upper arm close to your side and elbow at a right angle. Push the forearm to the side against the wall. Hold approx. 5 secs.
Stand in a doorway with you elbow close to your body and bent at a right angle. Place your hand against the wall. Push your hand inwards against the wall. Hold 5 secs. Relax.
Stand with your upper arm close to your side, elbow at a right angle and the back of your hand against a wall. Push the back of your hand against the wall. Hold approx. 5secs.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Sit. Place your hand on the front of the opposite shoulder. Feel your shoulder with your fingers making sure that the shoulder does not come forward. Move your shoulder gently 1 cm back and 2 cm up. Later on, exercise is done without palpation or visual confirmation of movement.
Sit. Place your hand on the front of the opposite shoulder. Feel your shoulder with your fingers. Move your shoulder gently 1 cm forward and 2 up from resting position. Later on, exercise is done without palpation or visual confirmation of movement.
Stand facing a rubber exercise band with your knees and hips slightly bent. Pull the band alternately with the left and right hand keeping the pelvis still.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Repeat 3 x 3 times.
Stand in a doorway with you elbow close to your body and bent at a right angle. Place your hand against the wall. Push your hand inwards against the wall. Hold 5 secs.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Stand with your upper arm close to your side, elbow at a right angle and the back of your hand against a wall. Push the back of your hand against the wall. Hold approx. 5 secs.
Stand sideways against a wall with your upper arm close to your side and elbow at a right angle. Push the forearm to the side against the wall. Hold approx. 5 secs.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Sit or stand holding on to a rubber exercise band with both hands. Pull the band with both arms pushing the shoulder blades together.
Stand straight holding an exercise band. Move your arm forward, pulling the band. Slowly return.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Repeat 3 x 15-25 times.
Stand keeping your upper arm close to the side and elbow at a right angle. Hold a rubber exercise band. Pull the band toward your stomach and hold for 5 secs.
Hold an exercise band with both hands. Pull the band outwards to about 45-60 degrees with back of your hand leading the movement. Hold for 5 secs.
Repeat 3 x 15-25 times BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s)

Phase IV (9-12 weeks)
Stand or sit with the hand of the arm to be exercised on your opposite hip. Hold on to a rubber exercise band. Pull the band up towards the opposite side.
Stand with your arm up and out to the side. Hold a rubber exercise band. Pull the band down and across your body letting your thumb lead the movement.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Alternatively, Sit on a chair with your arm lifted to the side and your elbow at a right angle supported on a table. Hold on to a rubber exercise band which is fastened behind you. Pull the band keeping elbow bent and resting on the table.
Stand keeping your upper arm close to the side and elbow at a right angle. Hold a rubber exercise band. Pull the band toward your stomach.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s) Alternatively, Sit on a chair with your arm lifted out to the side and elbow at a right angle supported on a table. Hold on to a rubber exercise band which is in front on you. Pull the band keeping your elbow bent and resting on the table.
Stand keeping your upper arm close to the side and elbow at a right angle. Hold a rubber exercise band. Pull the band by turning your forearm outwards.
BMJ Publishing Group Limited (BMJ) disclaims all liability and responsibility arising from any reliance Supplemental material placed on this supplemental material which has been supplied by the author(s)