Intramedullary nailing of proximal tibia fractures--an anatomical study comparing three lateral starting points for nail insertion.
BACKGROUND
Intramedullary nailing is challenging in proximal tibia fractures, associated with high rates of malalignment. To date, no studies report the potential of lateral tibia nail insertion to correct primary valgus malalignment, commonly seen in proximal quarter fractures.


METHODS
18 fresh-frozen cadaver lower extremities were used to simulate an AO/OTA 41-A3 fracture. Six nails (Expert Tibial Nailing System, Synthes, Salzburg, Austria) were inserted at the lateral third, six nails at the middle third and six nails at the medial third of the lateral tibia plateau. After nail insertion, alignment in the coronal plane was recorded.


RESULTS
Mean varus malalignment was dependent on the entry point at the lateral tibia plateau. Mean varus malalignment was 16 degrees if nails were inserted at the lateral third, 10 degrees at the middle third and 4 degrees after nail insertion at the medial third. If nails were inserted from the medial third, valgus malalignment was recorded in two specimens.


CONCLUSIONS
The effect of correction of coronal malalignment in proximal tibia fractures is dependent on the point of nail entry at the lateral plateau. Primary valgus deformation up to 20 degrees can be corrected by inserting tibia nails at the lateral third of the lateral tibia plateau. Surgeons should be aware of possible varus deformity and valgus malalignment despite lateral nail insertion.
Weninger
Patrick
P
Lorenz Boehler Trauma Hospital, Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Cluster for Tissue Regeneration, Donaueschingenstrasse 13, 1200 Vienna, Austria. patrick.weninger@gmx.net
Tschabitscher
Manfred
M
Traxler
Hannes
H
Pfafl
Veronika
V
Hertz
Harald
H
D000328:Adult; D001696:Biomechanical Phenomena; D001858:Bone Nails; D002102:Cadaver; D005260:Female; D005594:Fracture Fixation, Intramedullary / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D017759:Fractures, Malunited / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008953:Models, Anatomic; D019919:Prosthesis Implantation / Q000379:methods*; D013978:Tibial Fractures / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome