Medial approach for tibial bone graft: anatomic study and clinical technique

The purpose of this study is to quantify the amount of bone graft material present in the proximal tibia via a lateral versus a medial approach, as well as describe an alternative technique for obtaining this bone graft material. A quantitative anatomic and statistical analysis and comparison are presented. The goal of this study is to demonstrate the advantages and simplicity associated with utilizing the proximal tibia as a bone graft harvest site in oral and maxillofacial surgery via a medial approach.

Forty lower extremities from 20 cadavers were studied. All specimens were dissected, and anatomic landmarks were recorded. Anatomic structures, including vessels, nerves, muscle attachments, articular surfaces, and their relationships to various anatomic landmarks were identified, measured with a linear millimeter ruler, and recorded. Bone harvest was accomplished using either a medial (20 extremities) or lateral (20 extremities) approach. The amount of bone available for harvest using both techniques was compared. Variables evaluated included volume of graft, age, gender, and relationships among anatomic structures.

The mean volume of bone harvested was 25.0 mL for the lateral approach and 24.9 mL for the medial approach (range, 14 to 34 mL). The Mann-Whitney U test revealed no significant difference in mean volume of graft obtained when comparing the medial and lateral approaches (P =.9250). Pearson's correlation test revealed no correlation between age (P =.089 medial and P =.174 lateral) or gender (P =.3120 medial and P =.4440 lateral). The lateral anatomic structures evaluated included the anterior tibial vessels that emerged from the interosseous hiatus 14.3 mm inferior to tibial perpendicular and 42.6 mm lateral to the tibial parallel line. The distance from the tibial perpendicular to the articular surface did not significantly differ when comparing the medial (33.65 mm) and lateral (33.25 mm) anterior tibial surfaces. The mean length of the oblique line was 17.9 mm, and the superior portion of this line was 14.65 mm above the tibial perpendicular line.

Equal amounts of bone graft material are available for harvest from the medial and lateral aspects of the proximal tibia. Knowledge of important anatomic landmarks can be used preoperatively to allow for safe dissection and harvest of autogenous bone from the proximal tibia. The dissection of medial proximal tibia and harvest of bone graft material may be accomplished efficiently with minimal chances of damage or morbidity to vital adjacent structures.