Long-term patient reported outcomes after revision surgery for lower extremity nonunion: A retrospective cohort study.

INTRODUCTION: Ongoing lower extremity long-bone nonunion is a devastating condition and associated with substantial patient morbidity. There is limited evidence regarding physical and mental function after surgical management of lower extremity nonunions. The purpose of this study was to assess general physical and mental health and lower extremity specific physical function of patients that underwent surgery for a lower extremity long-bone nonunion. METHODS: One-hundred and twenty-four adult patients who underwent successful surgical management for a lower extremity long-bone nonunion between June 2002 and December 2021 were evaluated at an average follow-up of 8.6 years (interquartile range [IQR]: 4 - 12). General physical and mental health was assessed with the Short-Form 12 (SF-12) physical (PCS) and mental (MCS) component summaries, and lower extremity specific physical function with the Lower Extremity Functional Scale (LEFS). Multivariable linear regression was performed to identify variables that were independently associated with outcomes. RESULTS: The median LEFS was 50 (IQR: 37 - 63) and the median SF-12 PCS was 43 (IQR: 33 - 52), which are both lower than normative population scores (LEFS: 77 and PCS: 51, p < 0.0001). The median SF-12 MCS was 50, which was comparable to the normative population score of 51 (p < 0.0001). The number of previous surgeries before the index nonunion treatment (p = 0.018 and p = 0.041) and the number of revision surgeries after the index nonunion treatment (p = 0.022 and p = 0.041) were associated with lower LEFS and SF-12 PCS scores. CONCLUSION: At an average of 8.6 years after lower extremity nonunion surgery that led to bone healing, patients continue to report lower general and lower extremity specific physical functioning compared to the normative population. The number of surgical attempts to obtain definitive healing was associated with compromised physical function scores. Mental health scores may return close to normative population scores. These results can be used to inform patients and guide treatment strategies and healthcare policies.

Characteristics and Outcomes of Occult Infections in Presumed Aseptic Nonunions: A Retrospective Cohort Study.

OBJECTIVES: To determine (1) the rate of positive cultures in presumed aseptic nonunions, (2) the rate and microbial spectrum of positive cultures that represented occult infection, and (3) rates of nonunion healing. DESIGN: Retrospective cohort study. SETTING: Tertiary referral center. PATIENTS SELECTION CRITERIA: Adult patients with a presumed aseptic nonunion treated with single-stage revision between 2002 and 2022. OUTCOME MEASURES AND COMPARISONS: The rate of positive cultures compared for 2 protocols: old: 1-2 samples cultured 7 days versus new: 5 samples cultured 14 days. The rate of positive cultures meeting occult infection criteria with the new protocol (≥2 samples with phenotypically indistinguishable microorganisms, or ≥1 sample with a high virulent microorganism). Nonunion healing rates between protocols and between groups based on culture results with the new protocol. RESULTS: One hundred seventy-nine patients were included. The rate of positive cultures was 14% (n = 15/105) with the old protocol and 51% (n = 38/74) with the new protocol (P < 0.001). With the new protocol, the rate of positive cultures meeting occult infection criteria was 19% (n = 14/74), and coagulase-negative staphylococci (48%) and Cutibacterium acnes (38%) were the most common microorganisms. Nonunion healing rates after the primary revision did not differ between protocols (old: 82% vs. new: 86%, P = 0.41) and groups based on culture result (sterile: 86% vs. occultly infected: 93%, P = 0.66). The final overall nonunion healing rate was 97%. CONCLUSIONS: Occult infections were identified in 1 in 5 presumed aseptic nonunions using a standardized protocol with 5 intraoperative samples cultured 14 days and were predominantly caused by slow growing, gram-positive microorganisms. The local spectrum and antimicrobial sensitivity of occult infections should be considered when developing empiric antimicrobial protocols. Patients with presumed aseptic nonunions can expect high healing rates, regardless of the culture result. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.