BACKGROUND: Elderly patients suffering from complex, non-reconstructable fractures of the proximal humerus are commonly treated by primary implantation of a shoulder endoprosthesis. One of the most critical factors for success or failure of treatment is still the refixation of the tuberosities. METHOD: Using sheep infraspinatus tendons with attached tuberosities three different suture materials were investigated. For 2 of the suture materials 4 tests were accomplished and 5 tests were carried out for the third suture material. A material testing machine was used to perform cyclic loading tests (20 mm/min, Fmin=50 N, Fmax=100 N, respectively after 50 cycles: Fmax+50 N until failure). RESULTS: The results showed large variations in the average maximum forces (152.4 N for suture 1, 219.9 N for suture 2 and 452.3 N for suture 3). All tests showed a high initial lengthening and caused incision-like defects in the bone or tendon and led to failure and high displacement of the tuberosities. CONCLUSION: Due to these results suture materials have a limited usefulness for refixation of tuberosities as an increased risk of obstruction for bony consolidation can result.
BACKGROUND: Elderly patients suffering from complex, non-reconstructable fractures of the proximal humerus are commonly treated by primary implantation of a shoulder endoprosthesis. One of the most critical factors for success or failure of treatment is still the refixation of the tuberosities. METHOD: Using sheep infraspinatus tendons with attached tuberosities three different suture materials were investigated. For 2 of the suture materials 4 tests were accomplished and 5 tests were carried out for the third suture material. A material testing machine was used to perform cyclic loading tests (20 mm/min, Fmin=50 N, Fmax=100 N, respectively after 50 cycles: Fmax+50 N until failure). RESULTS: The results showed large variations in the average maximum forces (152.4 N for suture 1, 219.9 N for suture 2 and 452.3 N for suture 3). All tests showed a high initial lengthening and caused incision-like defects in the bone or tendon and led to failure and high displacement of the tuberosities. CONCLUSION: Due to these results suture materials have a limited usefulness for refixation of tuberosities as an increased risk of obstruction for bony consolidation can result.
Authors: G Russell Huffman; John M Itamura; Michelle H McGarry; Long Duong; Jeremy Gililland; James E Tibone; Thay Q Lee Journal: J Shoulder Elbow Surg Date: 2008-01-30 Impact factor: 3.019
Authors: Takashi Yanagawa; Cheryl J Goodwin; Kevin B Shelburne; J Erik Giphart; Michael R Torry; Marcus G Pandy Journal: J Biomech Eng Date: 2008-04 Impact factor: 2.097