The effects of dual plating on the vascularity of the distal femur

Abstract

Aims Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity. Methods A total of eight cadaveric lower limb pairs were arbitrarily assigned to either 1) isolated lateral plating, or 2) lateral and medial plating of the distal femur, with four specimens per group. Contralateral limbs served as matched controls. Pre- and post-contrast MRI was performed to quantify signal intensity enhancement in the distal femur. Further evaluation of intraosseous vascularity was done with barium sulphate infusion with CT scan imaging. Specimens were then injected with latex medium and dissection was completed to assess extraosseous vasculature. Results Quantitative MRI revealed a mean reduction of 21.2% (SD 1.3%) of arterial contribution in the lateral plating group and 25.4% (SD 3.2%) in the dual plating group (p = 0.051); representing a mean decrease in arterial contribution of 4.2%. The only significant difference found between both experimental groups was regionally, at the lateral aspect of the distal femur with a mean drop in arterial contribution in the lateral plating group of 18.9% (SD 2.6%) versus 24.0% (SD 3.2%) in the dual plating group (p = 0.048), representing a mean decrease in arterial contribution of 5.1%. Gross dissection revealed complete destruction of periosteal vessels underneath either medial or lateral plates in both groups. The network of genicular branches contributing to the posterior and distal femoral condyles was preserved in all specimens. A medial vascular pedicle was found dividing from the superficial femoral artery at a mean 12.7 cm (SD 1.7) proximal to the medial epicondyle and was undisrupted in the dual plating group. Conclusion Lateral locking-plate application resulted in mean 21.2% reduction in distal femur vascularity. Addition of medial plates did not further markedly decrease vascularity. As such, the majority of the vascular insult occurred with lateral plating alone. Supplemental medially based fixation did not lead to marked devascularization of the distal femur, and should therefore be considered in the setting of comminution and poor bone stock in distal femoral fractures. Further clinical research is required to confirm the results of this study. Cite this article: Bone Joint J 2020;102-B(4):530–538.

“A Modified Anterolateral Swashbuckler Approach for Distal Femoral Fractures: Description and Outcomes”

“…The authors sample size is small in order to draw conclusions applicable to the general population: although they did not encounter any di culties in patellar mobilization during the surgical procedures, this statement should be veri ed and supported by future cadaveric studies [37]. In support of the authors conclusions, a contrast enhanced knee MRI study could be useful to verify the integrity of the peri-patellar circulation and a doppler ultrasound study could verify the intra-patellar blood ow [38] [39]. Another limitation of the current study is the difference in the skin incision between the current authors and Starr et al [13] and by Beltran et al [19]: the current authors decided to make a skin incision 2 cm lateral to the patellar tendon.…”

Three-dimensional computed tomography mapping and analysis of distal femur fractures (AO/OTA types 33A, 33B, and 33C)

“…The biomechanical study proved that the medial plate opposed varus stress of the lower limb, shared part of stresses from the lateral plating (20), and thus increased the fracture stability (18). Rollick et al (24) reported that an addition of a plate to the medial side of the distal femur after a laterally based plate did not further influence the vascularization of the femur. Besides the lateral surgical approach, additional medial exposure may be needed for severely comminuted supracondylar fractures in which the medial plate is required.…”

Modified use of the proximal humeral internal locking system (PHILOS) plate for distal femoral nonunions

“…The application of medial distal femoral plates has been controversial because of the concern for damage to the branching arteries of the deep femoral artery (DFA) and the distal femur nerves. Cadaveric studies suggest however, that medial plate application can be performed safely [22,23].…”