Mechanical resistance of gastric bands - comparison between new bands and bands within the patient for at least two years.
BACKGROUND
Morbid obesity is a rapidly increasing health risk in industrialized countries, and is associated with serious co-morbidities. Since conservative medical therapies fail to sustain significant weight loss, adjustable gastric banding (AGB) has become an established therapy for morbid obesity. To our knowledge there have been no trials assessing whether gastric bands implanted in the patient for some time can withstand the same mechanical stress as a new band.


METHODS
The mechanical resistance of unused and used gastric bands was tested through the Tensile Test, to evaluate if a material is strong and rigid enough to withstand the loads experienced in use. 9 bands were tested, 2 of which were unused.


RESULTS
The tested new Swedish AGB (SAGB) resisted 361 Newtons (N, 36.8 kg) until tearing, and the new LAGB (Inamed) 157 N (16 kg). The 7 SAGB which had been in a patient for at least 2 years, pulled apart at a mechanical stress of 250.6 N (25.54 kg).


CONCLUSIONS
The new SAGB had a higher mechanical tensile strength than any of the used bands placed in the body for 2 years.
Lanthaler
M
M
Department of General and Transplant Surgery, University Hospital of Innsbruck, Innsbruck Austria.
Schwienbacher
F
F
Tembler
J
J
Weiss
H
H
Mittermair
R
R
Aigner
F
F
Nehoda
H
H
D005260:Female; D015391:Gastroplasty; D006801:Humans; D008297:Male; D008422:Materials Testing; D019736:Prostheses and Implants; D013314:Stress, Mechanical; D013718:Tensile Strength