Session VIII - Femur/Knee

*Plating of Femoral Shaft Fractures: Traditional ORIF versus Submuscular Fixation

Dennis Vogt, MD; Michael Zlowodzki, MD; Peter A. Cole, MD; Philip J. Kregor, MD; Vanderbilt University Medical Center, Nashville, Tennessee, USA; and the University of Mississippi Medical Center, Jackson, Mississippi, USA (a-Synthes, AO Research Foundation)

Purpose: Indications for plate fixation of a femoral shaft fracture include associated femoral neck fracture, associated acetabular fracture, vascular injury, associated spinal fracture, young age (adolescent), and multisystem trauma. Published series of traditional plate fixation of the femur note rates of up to 69% primary bone grafting, 13% infection, 15% nonunion, 68% late complications, and 25% secondary surgical procedures. A shift >from traditional plating to submuscular plating has thus ensued. This series entails an all-inclusive review of the plate fixation experience by two orthopaedic trauma surgeons in a 5-year period at a university trauma center. Specifically, a comparison was performed of reduction quality, union rates, and infection rates between traditional plate fixation and submuscular fixation.

Methods: Between June 1996 and May 2001, 40 acute diaphyseal femoral fractures in 37 patients were managed by using dynamic compression plating via traditional "biologic" plating with a formal lateral incision (N = 19), or submuscular plate fixation using only a proximal and distal incision (N = 21). Traditional plating was exclusively used prior to February 1999; submuscular plating was done exclusively after that date. No bone grafting was used for either group. Indications for plate fixation included multi-trauma in 16 patients, ipsilateral femoral neck fracture in 7 patients, ipsilateral acetabular fracture in 5 patients, spinal fracture in 4 patients, adolescence in 4 patients, vascular injury in 2 patients, and pregnancy in 2 patients. Fractures were classified according to the AO/OTA classification. Blinded quantitative assessment of reduction quality was performed without knowledge of operative technique. Malreductions were defined as more than 3° varus/valgus malalignment or more than 10 mm of translation or both. Infectious complications were defined as the need for any irrigation and debridement or prolonged antibiotic use. Average follow-up was 15 months.

Results: Of the 40 fractures, there were 6 AO/OTA classification 32-A2, 17 A3, 11 B2, 5 B3, 1 C2, and 3 C3 femoral shaft fractures. There were 8 open fractures (4 type I, 2 type II, 1 type IIIA, 1 type IIIC) and 32 closed fractures. The average patient age was 26 years (range, 14 to 53). No significant demographic differences were seen between the two groups. In assessing reduction quality, there were no malreductions in the traditional plating group and six in the submuscular plating group. The deformities included five cases of more than 10-mm sagittal plane (lateral radiograph) deformity and one case of 5° of excess valgus deformity. Complications in the traditional plating group included one nonunion and two infections requiring staged irrigation and debridements, antibiotic bead placement, and administration of intravenous antibiotics. No infections or nonunions were noted in the submuscular group. However, there were two cases in the submuscular group of excessive callus formation requiring quadriceptoplasty and one case requiring manipulation under anesthesia. Full weight bearing was achieved at an average of 16 weeks in the traditional plating group and 15 weeks in the submuscular group.

Discussion and Conclusion: Current dogma suggests that submuscular plate fixation is superior to traditional "biologic" plating techniques. These results represent the 5-year experience of two fellowship-trained orthopaedic trauma surgeons experienced with traditional and submuscular plating. Six of 20 (30%) of the submuscular plating group had a malreduction and 3 of 20 (15%) required further operative intervention secondary to excessive callus formation. In contrast, these complications were not seen in the traditional open-plating group. However, two significant infections (11%) and one nonunion (5%) were seen in the open traditional plating group. In conclusion, submuscular plating of the femur is associated with a high malreduction rate but may lessen complications of infection and malunion.