RELEVANCE OF OSTEOTOMY AND IMPLANT CHARACTERISTICS IN INTER- AND SUBTROCHANTERIC OSTEOTOMIES - EXPERIMENTAL EXAMINATION UNDER ALTERNATING AND STATIC LOAD AFTER STABILIZATION WITH DIFFERENT DEVICES INCLUDING GAMMA-NAIL OSTEOSYNTHESIS

Authors
Citation
W. Friedl, RELEVANCE OF OSTEOTOMY AND IMPLANT CHARACTERISTICS IN INTER- AND SUBTROCHANTERIC OSTEOTOMIES - EXPERIMENTAL EXAMINATION UNDER ALTERNATING AND STATIC LOAD AFTER STABILIZATION WITH DIFFERENT DEVICES INCLUDING GAMMA-NAIL OSTEOSYNTHESIS, Archives of orthopaedic and trauma surgery, 113(1), 1993, pp. 5-11
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Orthopedics,Surgery
ISSN journal
0936-8051
Volume
113
Issue
1
Year of publication
1993
Pages
5 - 11
Database
ISI
SICI code
0936-8051(1993)113:1<5:ROOAIC>2.0.ZU;2-O
Abstract
The put-pose of this experimental examination was to determine the loa d-bearing capacity (LBC) of different inter- and subtrochanteric fract ures under alternating physiological and static loads. These fractures are typical injuries of the geriatric patient, and full LBC restorati on is needed for mobilisation. From patients over 60 years old at the time of death, 301 femora were obtained and randomly allocated to the following osteotomy (OT) groups: A(1), flat and steep OT; A(2), OT wit h 2/3 and complete medial cortical defect; reversed inter- (A(3)) and subtrochanteric OT; subtrochanteric resection and double plate compoun d osteosynthesis (DPCO); and the control group (no OT). Following oste osynthesis various devices were tested: condylar plate, 130 degrees an gle nail plate, 145 degrees angle nail plate, double T profile angle n ail plate, 135 degrees DHS, 150 degrees DHS after valgisating displace ment OT, Ender nails, gamma nail and Orthofix external fixator. The fe mora were tested under alternating physiological load and under static load. The load-bearing capacity (LBC) was 5141 +/- 1621 N in flat A(1 ) OT, 4502 +/- 1621 N in steep A(1) OT and 3767 +/- 1500 N in A(2) OT with partial defect. In reversed intertrochanteric OT the LBC was 3770 +/- 1798 N and in the reversed subtrochanteric OT, 5308 +/- 2330 N. I n Az OT with complete medial defect, only the gamma nail (5672 +/- 726 N) and the DHS after valgisating displacement OT (7261 +/- 1794 N) sh owed a high LBC and no alternating load instability. After subtrochant eric resection and DPCO (7415 +/- 1840 N) the LBC was the same as that of the control femora (7271 +/- 1941 N). The influence of the type of OT on the LBC and instability under alternating physiological load is also dependent on the implant characteristics. Only gamma nail osteos ynthesis shows a high LBC in all types of OT, so it can be recommended as a single device for all inter- and subtrochanteric fractures of th e elderly. In pathological subtrochanteric fractures involving metasta ses resection, the DPCO should be used because of the very high LBC. W hen the gamma nail is not used, only with a differentiated therapy reg imen for the various types of inter- and subtrochanteric OT can a phys iological LBC restoration be obtained.