Pin Site-Related Outcomes After Temporary Staging External Fixator Pin Placement Using the Self-Drilling Pin Insertion Technique.

Abstract

Objectives: To report on pin-related complications in patients who underwent temporary staging external fixation using a self-drilling pin insertion technique.

Methods:

Design: Retrospective cohort study.

Setting: Single tertiary referral level 1 trauma center.

Patient selection criteria: Adult patients were included who underwent temporary spanning external fixation of the lower extremity (AO/OTA 32, 33, 41, 42, 43, 44, 81, 82, 83, 84, and 85 fractures) using self-drilling and self-tapping pins placed using the self-drilling technique (Stryker Hoffman External Fixation System, Kalamazoo, MI) between August 1, 2015, and December 31, 2022, with a minimum follow-up of 90 days. The self-drilling technique included use of a soft tissue sleeve for pin protection in the femur and tibia, release of the tourniquet if inflated, and full speed insertion with the final turns completed by hand. Irrigation of the pin-bone interface was not typically used.

Outcome measures and comparisons: Outcome measures included pin site infection, pin loosening, loss of reduction in the external fixator, and deep infection of the primary surgical site.

Results: Two hundred sixty-five patients were included with a mean follow-up of 556 days. The mean age was 50 years (range 18-86 years). One hundred fifty-five patients (59%) were male. One thousand one hundred fifty-four total pins were placed: 289 (25%) in the femur (1 metaphyseal), 527 (46%) in the tibia (12 metaphyseal), 161 (14%) transfixion pins in the calcaneus, and 171 (15%) in the midfoot/forefoot. Seven patients (2.6%) developed a pin site infection. The infection rate for the total number of pins placed was 7 of 1154 (0.6%). One patient sustained a loss of reduction in the external fixator, and 3 pins were noted to be loose at the time of definitive fixation (2 in the tibial diaphysis and 1 in the first metatarsal shaft). In total, 35 of 265 patients (13.2%) developed deep fracture-related infection or septic nonunion in the postoperative period, none of which were associated with prior pin site infection.

Conclusions: The self-drilling technique for temporary external fixator pin insertion in this study demonstrated low rates of pin site infection, pin loosening, and loss of reduction.

Level of evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.