OTA 1997 Posters - Tibia Fractures
Increased Complications in Proximal Tibial Fractures Treated by IM Nailing
Peter Schandelmaier, MD, Prof. Christian Krettek, MD, Anette Kohl, Joachim Rudolf, Prof. Harald Tscherne, MD
Hannover Medical School, Hannover, Germany
Purpose: Proximal tibial fractures treated by IM nailing have significantly more complications and malunion compared to mid-shaft fractures.
Material and Methods: In a prospective study of 185 acute tibial shaft fractures which were treated from 1988 to 1994 by an AO unreamed tibial nail (URTN), we selected 83 cases on the basis of the starting point of the fracture and length of the fracture. We considered all fractures beginning within the proximal 30% of the tibia as proximal fractures (16 cases). Sixty-seven cases we considered as mid-shaft (beginning distal to 30% of tibial length, and ending proximal to 70% of tibial length). The fracture length and location was measured on the postoperative x-ray of the whole leg and calculated as percent of total tibial length. The insertion angles and starting point on the tibia plateau was measured on the postoperative x-rays. The fractures were classified according to the AO classification. Soft tissue damage was graded according to Tscherne for closed injuries and according to Gustilo for open injuries. Follow-up was done until healing of the fracture at 6 weeks interval. Three months after bony union a last follow-up examination was done. The functional outcome was assessed with the Karlstrom and Olerud Score. Sixteen cases with beginning of the fracture within the proximal 30% of the tibia were compared to 67 fractures where the beginning was distal to the 30% of tibial length, and which ended proximal to 70% of tibial length. We had 35 closed and 48 open fractures. No case of penetrating trauma was included. In the proximal group we had 12 B-type fractures and 4 C-type fractures. The mid-shaft group had 12 A-type, 46 B- and 9 C-type fractures according to the AO classification.
| Results | Proximal fracture | Mid-shaft fracture |
| N | 16 | 67 |
| Valgus deformity 5° - 10° | 5 | 1 |
| Varus deformity 5° - 10° | 1 | 3 |
| recurvatum deformity 5° - 10° | 3 | 2 |
| anterior apex deformity 5° - 10° | 6 | 1 |
| change of treatment | 6 | 6 |
| intraoperatively comminution of fracture | 3 | 2 |
| bolt failure proximal | 1 | 9 |
| bolt failure distal | 0 | 2 |
| bone graft | 3 | 5 |
Results: Both groups did not show statistically significant differences for age, polytrauma score, additional injury. We had no significant difference regarding operating time (108 min vs. 138 min). Drill bit breakage happened in 3 cases in the proximal group and in two cases in the distal group. 70% had multiple injuries. The incidence of apex anterior angulation and valgus deformities was significantly higher in the proximal group. We used additional fixation in 7/16 cases of the proximal group to eliminate possible toggling. The average time to bony healing did not differ between the two groups, as was the functional outcome.
Discussion: A significant problem in proximal tibial fractures remains anterior apex deformity. Change of treatment plan to a second IM nail did not always lead to excellent position. We used poller screws in 7 patients. These screws prevent redisplacement. A medial and anterior entry point of the nail predisposes to valgus and anterior apex deformities.
Conclusions: The treatment of proximal tibial fractures by IM nailing shows significantly more valgus and anterior apex angulation. The incidence of bolt failure was not different between the two groups. To prevent malunion additional 'poller screws' seem to be helpful.