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Published on: November 13, 2016
Infection rates and risk factors with magnetic intramedullary lengthening nails
Sandeep S Bains1, Jeremy A Dubin1, Connor Green2,3,4
1Lifebridge Health, Sinai Hospital of Baltimore, Rubin Institute for Advanced Orthopedics, Baltimore, MD, USA.
Introduction:
Surgical site infection (SSI) related to magnetic intramedullary lengthening nails (MILNs) can lead to delayed consolidation or loss of limb function, resulting in deleterious effects to a patient's quality of life. With the rise of MILNs, we sought to determine the incidence rate and risk factors for infection during limb lengthening with MILNs.
Methods:
We reviewed a consecutive series of patients who underwent femoral and/or tibial lengthening with an MILN at a single institution between 2012 and 2020 (n = 420). SSI was defined according to CDC-NHSN criteria (including superficial and deep infections) with postoperative surveillance time of 12 months. Demographic, health metrics, comorbidities, limb- and surgery-related factors, were assessed as potential risk mediators of SSI.
Results:
Incidence of SSI was 3.3 % (14/420). This was divided into superficial (0.5 %,2/420) and deep (2.9 %, 12/420) infections. Of deep infections, 75 % (9/12) were osteomyelitis. Of the 14 limbs that developed SSI, 57 % (8/14) had a history of prior external fixation in the same limb and 38 % (5/14) had a previous infection of the same limb. A subanalysis of patients with a history of prior external fixation in the same bone was associated with SSI, as compared to those without previous external fixation. None of the surgery-related infection risk factors reached statistical significance.
Discussion And Conclusion:
The total incidence of infection with MILNs was 3.3 % at 24 months follow-up. The risk of deep infection was 2.9 %. Patients with a history of previous external fixation and prior infection show an independent association with increased rate of infection recurrence in the same bone. These patients could be considered a high-risk group for developing deep tissue infection. Potential algorithms include prolonged oral antibiotics after MILN insertion or simultaneous injection of absorbable antibiotic at the time of the nail insertion.
Insights
Surgical site infections (SSIs) occur in 3.3% of patients undergoing limb lengthening with magnetic intramedullary lengthening nails (MILNs). Prior external fixation or infection significantly increases the risk of deep infection, suggesting a high-risk group.
Area of Science:
- Orthopedic surgery
- Infectious disease
- Biomaterials
Background:
- Surgical site infections (SSIs) following magnetic intramedullary lengthening nail (MILN) procedures can severely impact patient quality of life.
- The increasing use of MILNs necessitates a clear understanding of infection rates and associated risk factors.
Purpose of the Study:
- To determine the incidence rate of SSIs in patients undergoing limb lengthening with MILNs.
- To identify risk factors associated with the development of SSIs during MILN procedures.
Main Methods:
- Retrospective review of 420 patients who underwent femoral and/or tibial lengthening with MILNs (2012-2020).
- Infection classification based on CDC-NHSN criteria, with 12-month postoperative surveillance.
- Analysis of demographic, comorbidity, and limb/surgery-specific factors as potential risk factors for SSI.
Main Results:
- Overall SSI incidence was 3.3% (14/420), with deep infections accounting for 2.9% (12/420), predominantly osteomyelitis (75%).
- A history of prior external fixation (57%) or previous infection (38%) in the same limb was significantly associated with SSI.
- No surgery-related factors reached statistical significance for SSI risk.
Conclusions:
- The overall infection rate for MILN limb lengthening is 3.3%, with a 2.9% risk of deep infection.
- Patients with prior external fixation or infection in the same bone represent a high-risk group for recurrent infections.
- Consideration of prolonged antibiotics or antibiotic-eluting nail insertion may be beneficial for high-risk patients.
