Factors Affecting Outcomes of Hindfoot Fusion Nails for Acute Injury: A Multicenter Study

OBJECTIVE: – To evaluate the effect of joint preparation and patient factors on outcomes and complications in patients treated acutely with hindfoot fusion nails for ankle and pilon fractures.METHODS: – Design: – Retrospective chart review.Setting: – Thirteen US trauma centers and 2 UK trauma centers.Patient Selection Criteria: – Ankle and pilon fractures (AO-OTA types A-C) from 2010 to 2020 acutely treated definitively with hindfoot fusion nail were reviewed. Patients at least 18 years old and with minimum 6 months follow-up or earlier diagnosis of complication were included. Exclusion criteria included nonambulatory at baseline, prior internal fixation that failed and underwent revision, and prior tibiotalar or subtalar arthrodesis.Outcome Measurements and Comparisons: – The primary outcome was final postoperative ambulatory status. Secondary outcomes were infectious and fracture-related complications.RESULTS: – One hundred forty-nine patients (75 men; 74 women; age 20–99; median 63 years) were treated for ankle (104) or pilon (45; 8A, 13B, 24C) fractures. Eighty-five patients (44%) had open fractures and 55 (37%) had diabetes. Thirty-six patients (24%) had joint preparation at the time of surgery. Forty-five (30%) were made weight bearing as tolerated postoperatively; the median time to mobilize was 1.5 days (0–210) and to full weight bearing was 35 days (0–1462). Fifty-seven patients (85%) returned to their preinjury ambulatory status, which was not affected by joint preparation (50% vs. 59%, P = 0.327). Joint preparation led to higher articular fusion rates (94% vs. 24%; P = 0.001) and fewer hardware removals (19% vs. 42%, P = 0.013), but trended toward a higher fracture nonunion rate (19% vs. 8%, P = 0.053). Forty-five patients (30%) had infectious complications, 60 (40%) had a fracture-related complication, and 67 (45%) had additional procedures. Open fractures did not lead to any differences in superficial or deep infection. Insulin-dependent diabetes was associated with higher rates of infectious complications (31% vs. 15%, P = 0.028) and amputation (17% vs. 4%, P = 0.029).CONCLUSIONS: – Hindfoot fusion nails for acute ankle and pilon injuries had high complication rates. More complications occurred in patients with insulin-dependent diabetes. While 95% regained ambulation, only 57% returned to preoperative status. Joint preparation led to higher rates of articular fusion (94% vs. 24%, P < 0.001) but not fracture union (81% vs. 66%, P = 0.106).LEVEL OF EVIDENCE: – Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.