Fine wire versus locking plate fixation of type C pilon fractures

The successful treatment of high energy pilon fractures (AO-OTA 43C) can be achieved with a fine wire circular external fixator (CEF) or locking plate construct (ORIF). There is no consensus on whether ORIF or CEF achieves superior outcomes, and both have unique complications. We report early to mid-term outcomes comparing type C pilon fractures treated with ORIF and CEF.

An 8-year retrospective review was performed on all patients who underwent ORIF or CEF for closed 43C fractures in a tertiary orthoplastic centre. Outcomes included unplanned return to theatre prior to union including superficial and deep surgical site infections (SSI), non-union and post-traumatic osteoarthritis (PTOA) needing fusion.

76 patients underwent ORIF and 59 patients had CEF, with a mean follow-up of 2 years. 7/76 (9.2%) patients who underwent ORIF had a superficial SSI; 2 patients (2.6%) required a formal debridement for deep SSI; none required a flap. 13/59 patients (22%) had a pin track infection following CEF. With the numbers available, there was no significant difference in rates of unplanned return to theatre before bone healing (ORIF 7/76, 9.2%, CEF 9/59, 15.2%, p = 0.7), rates of mal-union (1.7% CEF, 3.9% ORIF, p = 0.7), deep SSI (p = 0.9), time to union (ORIF: 8.1 months v CEF 10.8 months, p = 0.51), non-union (p = 0.24) and fusion for PTOA (ORIF: 6/76, CEF 2/59, p = 0.46).

With correct patient selection, both ORIF and CEF offer equivalent and favourable early to mid-term outcomes with regard to deep SSI, non-union, mal-union and PTOA. Although statistically insignificant, ORIF with more than 2 plates carries a risk of superficial and deep SSI, whilst CEF is associated with a 22% pin track infection rate. These unique risks must be discussed with the patient as part of a shared decision-making process.