Session V - Knee / Tibia

Fri., 10/11/13 Knee/Tibia, PAPER #66, 3:33 pm OTA 2013

Alignment After Intramedullary Nailing of Distal Tibia Fractures Without Fibula Fixation

Anthony De Giacomo, MD; William R. Creevy, MD; Paul Tornetta, III, MD;
Boston University Medical Center, Boston, Massachusetts, USA

Background/Purpose: Recent studies have shown lower rates of malalignment after intramedullary nailing of distal tibia shaft fractures with fixation of the fibula. However, fixation of the fibula brings with it risks of its own. The purpose of this study is to evaluate the efficacy of intramedullary nailing of distal tibia fractures using modern techniques without fibula fixation in obtaining and maintaining alignment and to evaluate the level of fibula fracture and the OTA tibial fracture type on alignment.

Methods: 137 consecutive patients with distal tibia fractures form the basis of this study. Demographic data, comorbidities (smoking, diabetes mellitus), mechanism of injury, fracture characteristics (open vs closed, OTA/AO classification, presence and location of fibula fracture), canal fill ratio, and the techniques used for reduction and nailing were documented. Malalignment (occurring in the operating room) and malunion (at union) were defined as greater than 5° of angulation on the initial postoperative AP or lateral radiographs and the final radiographs after union, respectively. Complications included unplanned secondary procedures (dynamization, exchange, removal locking screws), infection, wound dehiscence and delayed/nonunion. The effect of the OTA fracture type and the presence of fibula fracture and its level on alignment were evaluated using analysis of variance.

Results: There were 137 consecutive patients (96 men and 41 women) aged 16-93 years (average 43) with 41 (30%) open and 96 (70%) closed fractures. Five patients with indirect ankle fractures were excluded. Ten were lost prior to complete union but are included in the analysis of postoperative alignment. Mechanism of injury did not predict presence or level of fibula fracture. Fibula fractures were proximal (39), at the level of (46), distal to (30), segmental (7), and absent (10) with respect to the tibia fracture. Varus/valgus and procurvatum/recurvatum angulation upon presentation was greatest when the fibula was fractured at the level of the tibia fracture (P = 0.001 and 0.028). Reaming was performed in 84% and distal locking was with two medial to lateral locking screws in 95% with 5% having an additional AP locking screw for coronal plane fracture or osteopenia. Three patients had blocking screws. 36 patients (26%) had intra-articular extension of which 20 were fixed with screws and or plate outside the nail. The ratio of the nail to narrowest canal diameter at the level of the tibia fracture averaged 1.93 (range, 0.5-3) and did not correlate with malalignment or malunion. The most common intraoperative reduction aids were nailing in relative extension, transfixion external fixation, and clamps at the fracture site. The most important factor was felt to be the ability to visualize the reduction in both planes through the point of distal locking. The overall malalignment rate was 2%. Two additional patients had hardware removal prior to union for wound complication or infection and united at 6° and 8° resulting in a final malunion rate of 3%. The OTA fracture type or level/presence of fibula fracture did not influence alignment (P = 0.8 and 0.9), malunion (P = 0.9 and 0.99), or the change in alignment during union, which averaged 0.9° and was within measurement error. There were 2 wound problems/infection, 5 delayed/nonunions, and 4 distal screw removals for irritation.

Conclusion: We found an overall low rate of both malalignment (2%) and malunion (3%) after intramedullary nailing of distal tibial shaft fracture without fibula fixation. We conclude that when techniques that allow for visualization through distal locking are used, fibula fixation is not necessary to obtain or maintain alignment. Additionally, standard two medial to lateral screws distally affords adequate stability to hold the reduction during union with a 0.9° difference in the initial postoperative and final united films.

Alphabetical Disclosure Listing

• The FDA has not cleared this drug and/or medical device for the use described in this presentation   (i.e., the drug or medical device is being discussed for an “off label” use).  ◆FDA information not available at time of printing. Δ OTA Grant.