PMID- 17986887
OWN - NLM
STAT- MEDLINE
DCOM- 20080219
LR  - 20131121
IS  - 0890-5339 (Print)
IS  - 0890-5339 (Linking)
VI  - 21
IP  - 10
DP  - 2007 Nov-Dec
TI  - Intramedullary stabilization of extraarticular proximal tibial fractures: a 
      biomechanical comparison of intramedullary and extramedullary implants including 
      a new proximal tibia nail (PTN).
PG  - 701-9
AB  - OBJECTIVES: To determine in the laboratory whether there are or are not 
      differences between individual geometrical designs of intramedullary and 
      extramedullary devices used for the fixation of extraarticular proximal tibial 
      fractures. METHODS: Five devices were tested: a newly developed Proximal Tibia 
      Nail (PTN), conventional double-plate osteosynthesis (DPO), the Less Invasive 
      Stabilization System (LISS), an augmented Unreamed Tibial Nail with a 
      T-stabilization-plate (UTN + TSP), and an external fixator (ExFix). A 10-mm 
      defect osteotomy was performed on paired human tibiae, and the proximal and 
      distal ends were potted in polymethylmethacrylate cement (PMMA). Each pair of 
      bones was randomly stabilized with the new PTN in 1 tibia (Groups PTN1 through 
      PTN4) and in 1 of the 4 comparative implants in the corresponding contralateral 
      bone. A biomechanical test of the bone implant construct was then performed with 
      a vertical axial force of 350, 600, and 900 N, a bending moment of 6 Nm and a 
      bidirectional rotational strain of 8 Nm. Displacement of bone fragments was 
      measured and depicted as a force-displacement diagram. RESULTS: For axial 
      loading, significant differences were seen between the PTN 2 group compared to 
      the LISS group (P = 0.016) and the PTN 4 group compared to the ExFix group (P = 
      0.016). No statistically significant differences were seen for the PTN 1 group 
      compared to the DPO group (P = 0.125) and the PTN 3 group compared to the UTN + 
      TSP group (P = 0.453). The bending stiffness of the PTN 1-4 groups was not 
      significantly different from any of the 4 alternative implants. There was 
      comparable torsional stiffness in all implant groups except for the UTN + TSP 
      group, which was less stable and significantly different from the PTN 3 group (P 
      = 0.016). CONCLUSIONS: Given the parameters of this investigation, the new PTN 
      would theoretically provide the same mechanical stability as the DPO in axial 
      loading. Higher stability in axial loading may be present when compared to the 
      LISS or the ExFix. Further clinical investigation of this implant will determine 
      its usefulness among proximal tibial fixation devices.
FAU - Hansen, Matthias
AU  - Hansen M
AD  - Clinic for Trauma, Hand, and Reconstructive Surgery, City Hospital, Worms, 
      Germany. hansen-mainz@gmx.de
FAU - Mehler, Dorothea
AU  - Mehler D
FAU - Hessmann, Martin Henri
AU  - Hessmann MH
FAU - Blum, Jochen
AU  - Blum J
FAU - Rommens, Pol Maria
AU  - Rommens PM
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Orthop Trauma
JT  - Journal of orthopaedic trauma
JID - 8807705
SB  - IM
MH  - Biomechanical Phenomena/instrumentation
MH  - *Bone Nails
MH  - Bone Plates
MH  - *External Fixators
MH  - Fracture Fixation/*instrumentation
MH  - Fracture Fixation, Intramedullary/instrumentation
MH  - Humans
MH  - Prosthesis Design
MH  - Tibial Fractures/physiopathology/*surgery
EDAT- 2007/11/08 09:00
MHDA- 2008/02/20 09:00
CRDT- 2007/11/08 09:00
PHST- 2007/11/08 09:00 [pubmed]
PHST- 2008/02/20 09:00 [medline]
PHST- 2007/11/08 09:00 [entrez]
AID - 00005131-200711000-00006 [pii]
AID - 10.1097/BOT.0b013e31815aba5e [doi]
PST - ppublish
SO  - J Orthop Trauma. 2007 Nov-Dec;21(10):701-9. doi: 10.1097/BOT.0b013e31815aba5e.