Purpose: The purpose of this systematic review was to detect the reliability of the currently available magnetic resonance imaging measurements used in the evaluation of repaired rotator cuff.
Methods: Search was performed using major electronic databases from their inception to February 2014. All studies reporting post-operative magnetic resonance assessment after rotator cuff repair were included. After the identification of available magnetic resonance criteria, reliability studies were further analysed. Descriptive statistics were used to summarize findings. Methodological quality was assessed using the Quality Appraisal of Reliability Studies checklist.
Results: One hundred and twenty studies were included in the review. Twenty-six different criteria were identified. Ten studies reported inter-observer reliability, and only two assessed intra-observer reliability of some of the identified criteria. Structural integrity was the most investigated criterion. The dichotomized Sugaya's classification showed the highest reliability (k = 0.80-0.91). All other criteria showed moderate to low inter-observer reliability. Tendon signal intensity and footprint coverage showed a complete discordance. Intra-observer reliability was high for the presence of structural integrity, and moderate to low for all other criteria. Methodological quality was high only for one study and moderate for three studies.
Conclusions: Twenty-six different criteria described by multiple classification systems have been identified for the magnetic resonance assessment of rotator cuff after repair. Reliability of most of them has not been analysed yet. With the data available, only the presence of structural integrity showed good intra- and inter-observer agreement.
Level of evidence: Systematic review of descriptive and qualitative studies, Level IV.