On 2014 Jul 09, Mathias Wellmann commented:

Comment regarding Kukkonen et al. Treatment of non-traumatic rotator cuff tears. A RANDOMISED CONTROLLED TRIAL WITH ONE-YEAR CLINICAL RESULTS, Bone Joint J 2014;96-B:75–81. PMID: 24395315

Dear Authors,

we read the study with great interest und discussed the clinical implications. We think the authors did a great job respecting formal aspects (prospectively randomized design, equivalent cohort size, homogeneous patient distribution). However, there are a few aspects of the study which are potentially misleading:

1. The title of the study is misleading or to general at best. A more precise title would be: Treatment of small, well compensated non-traumatic supraspinatus tendon tears. We think a study title should be as clear as possible and should especially answer the question: What issue was studied? The study of Kukkonen et al. exclusively investigated patients with small (<10mm) supraspinatus tendon tears, which were well compensated regarding range of motion (full range of motion, inclusion criteria). In its present form the title of the study may lead to a transfer of the results to patients with decompensated full-thickness tears of the supraspinatus tendon. Such transfer is not valid and should be prevented using a more precise study title.

2. All patients with an passive external rotation <30° and an elevation <120° were excluded from the study and the limitation of elevation and external rotation was defined as stiffness. However, a loss of elevation <120° is not a sufficient criterion to define shoulder stiffness. An adequate examination would have quantified passive glenohumeral abduction and external rotation (external rotation in comparison to the contralateral unaffected side). Further, the percentage of patients excluded because of shoulder stiffness should be indicated, since this is not a very common combination in patients with atraumatic rotator cuff tears. In the given form there is a risk that the study design systematically excludes patients with restricted range of motion caused by loss of strength and pain. This is a basic issue, since these are the typical patients, in which we think about rotator cuff refixation.

3. The type of supraspinatus-tears for the patients, that were included in the study should be clearly defined (full thickness versus partial thickness tears). The authors use the term „supraspinatus tendon tear comprising <75% of the tendon insertion and documented with MRI“. Thereby it is unclear, if partial articular und bursal sided tears involving <75% of the tendon substance were also included in the study. In the results section the authors indicate the sagittal diameter of the tears treated by surgery. Does that mean, that all tears were full-thickness tears?

4. It is unclear, if any of the patients had been treated by physiotherapy previous to the inclusion, or if this was an exclusion criterion as well. How did the authors deal with patients, that were randomized to be treated by surgery but did not agree to a surgical intervention.

5. The authors did not perform a follow up MRI or even sonography to determine the rerupture rate of the rotator cuff repairs. This would have been a substantial information estimating the clinical success of rotator cuff repair. If further follow up investigations are planned in the study design, we strongly recommend to perform MRI scans.

6. The Constant Score may not be the most helpful score with regard to outcome discrimination for a patient population with „ full range of motion“, since it strongly estimates range of motion (40 points) compared to pain (15 points) and the level of daily actvities (20 points). For such patients more detailed patient reported outcomes (PROs) should be beneficial.

We recommend to revise the marked aspects to reach the highest possible scientific impact for this publication.

Mathias Wellmann on behalf of the Shoulder committee of the AGA - Society for Arthroscopy and Joint Surgery

On 2014 Jul 09, Mathias Wellmann commented:

Comment regarding Kukkonen et al. Treatment of non-traumatic rotator cuff tears. A RANDOMISED CONTROLLED TRIAL WITH ONE-YEAR CLINICAL RESULTS, Bone Joint J 2014;96-B:75–81. PMID: 24395315

Dear Authors,

we read the study with great interest und discussed the clinical implications. We think the authors did a great job respecting formal aspects (prospectively randomized design, equivalent cohort size, homogeneous patient distribution). However, there are a few aspects of the study which are potentially misleading:

1. The title of the study is misleading or to general at best. A more precise title would be: Treatment of small, well compensated non-traumatic supraspinatus tendon tears. We think a study title should be as clear as possible and should especially answer the question: What issue was studied? The study of Kukkonen et al. exclusively investigated patients with small (<10mm) supraspinatus tendon tears, which were well compensated regarding range of motion (full range of motion, inclusion criteria). In its present form the title of the study may lead to a transfer of the results to patients with decompensated full-thickness tears of the supraspinatus tendon. Such transfer is not valid and should be prevented using a more precise study title.

2. All patients with an passive external rotation <30° and an elevation <120° were excluded from the study and the limitation of elevation and external rotation was defined as stiffness. However, a loss of elevation <120° is not a sufficient criterion to define shoulder stiffness. An adequate examination would have quantified passive glenohumeral abduction and external rotation (external rotation in comparison to the contralateral unaffected side). Further, the percentage of patients excluded because of shoulder stiffness should be indicated, since this is not a very common combination in patients with atraumatic rotator cuff tears. In the given form there is a risk that the study design systematically excludes patients with restricted range of motion caused by loss of strength and pain. This is a basic issue, since these are the typical patients, in which we think about rotator cuff refixation.

3. The type of supraspinatus-tears for the patients, that were included in the study should be clearly defined (full thickness versus partial thickness tears). The authors use the term „supraspinatus tendon tear comprising <75% of the tendon insertion and documented with MRI“. Thereby it is unclear, if partial articular und bursal sided tears involving <75% of the tendon substance were also included in the study. In the results section the authors indicate the sagittal diameter of the tears treated by surgery. Does that mean, that all tears were full-thickness tears?

4. It is unclear, if any of the patients had been treated by physiotherapy previous to the inclusion, or if this was an exclusion criterion as well. How did the authors deal with patients, that were randomized to be treated by surgery but did not agree to a surgical intervention.

5. The authors did not perform a follow up MRI or even sonography to determine the rerupture rate of the rotator cuff repairs. This would have been a substantial information estimating the clinical success of rotator cuff repair. If further follow up investigations are planned in the study design, we strongly recommend to perform MRI scans.

6. The Constant Score may not be the most helpful score with regard to outcome discrimination for a patient population with „ full range of motion“, since it strongly estimates range of motion (40 points) compared to pain (15 points) and the level of daily actvities (20 points). For such patients more detailed patient reported outcomes (PROs) should be beneficial.

We recommend to revise the marked aspects to reach the highest possible scientific impact for this publication.

Mathias Wellmann on behalf of the Shoulder committee of the AGA - Society for Arthroscopy and Joint Surgery