TY  - JOUR
A1  - Hackl, Michael
A1  - Buess, Eduard
A1  - Kammerlohr, Sandra
A1  - Nacov, Julia
A1  - Staat, Manfred
A1  - Leschinger, Tim
A1  - Müller, Lars P.
A1  - Wegmann, Kilian
T1  - A "comma sign"-directed subscapularis repair in anterosuperior rotator cuff tears yields biomechanical advantages in a cadaveric model
JF  - The american journal of sports medicine
N2  - Background:
Additional stabilization of the “comma sign” in anterosuperior rotator cuff repair has been proposed to provide biomechanical benefits regarding stability of the repair.
Purpose:
This in vitro investigation aimed to investigate the influence of a comma sign–directed reconstruction technique for anterosuperior rotator cuff tears on the primary stability of the subscapularis tendon repair.
Study Design:
Controlled laboratory study.
Methods:
A total of 18 fresh-frozen cadaveric shoulders were used in this study. Anterosuperior rotator cuff tears (complete full-thickness tear of the supraspinatus and subscapularis tendons) were created, and supraspinatus repair was performed with a standard suture bridge technique. The subscapularis was repaired with either a (1) single-row or (2) comma sign technique. A high-resolution 3D camera system was used to analyze 3-mm and 5-mm gap formation at the subscapularis tendon-bone interface upon incremental cyclic loading. Moreover, the ultimate failure load of the repair was recorded. A Mann-Whitney test was used to assess significant differences between the 2 groups.
Results:
The comma sign repair withstood significantly more loading cycles than the single-row repair until 3-mm and 5-mm gap formation occurred (P≤ .047). The ultimate failure load did not reveal any significant differences when the 2 techniques were compared (P = .596).
Conclusion:
The results of this study show that additional stabilization of the comma sign enhanced the primary stability of subscapularis tendon repair in anterosuperior rotator cuff tears. Although this stabilization did not seem to influence the ultimate failure load, it effectively decreased the micromotion at the tendon-bone interface during cyclic loading.
Clinical Relevance:
The proposed technique for stabilization of the comma sign has shown superior biomechanical properties in comparison with a single-row repair and might thus improve tendon healing. Further clinical research will be necessary to determine its influence on the functional outcome.
Y1  - 2021
U6  - http://dx.doi.org/10.1177/03635465211031506
SN  - 1552-3365
SN  - 0363-5465
VL  - 49
IS  - 12
SP  - 3212
EP  - 3217
PB  - Sage
CY  - London
ER  - 
TY  - JOUR
A1  - Hackl, Michael
A1  - Nacov, Julia
A1  - Kammerlohr, Sandra
A1  - Staat, Manfred
A1  - Buess, Eduard
A1  - Leschinger, Tim
A1  - Müller, Lars P.
A1  - Wegmann, Kilian
T1  - Intratendinous Strain Variations of the Supraspinatus Tendon Depending on Repair Technique: A Biomechanical Analysis Regarding the Cause of Medial Cuff Failure
JF  - The American Journal of Sports Medicine
Y1  - 2021
U6  - http://dx.doi.org/10.1177/03635465211006138
SN  - 1552-3365
SN  - 0363-5465
VL  - 49
IS  - 7
SP  - 1847
EP  - 1853
PB  - Sage
CY  - London
ER  -