Can We Predict the Need for Unplanned Reoperation After Nonunion Repair?

Microbiome of infected fracture nonunion: Does it affect outcomes?

BACKGROUND

Infected fracture nonunions often require prolonged treatment and recovery courses. It is unclear whether the bacterial microbiome influences the time to healing as well as the eradication of infection. The goals of this study are (1) to assess the bacterial microbiome affecting infected nonunions and (2) to evaluate the effects of bacterial speciation on associated outcomes.

METHODS

Between 2006 and 2022, data from 551 adult patients from a single academic institution who presented with a fracture nonunion were analyzed retrospectively for infection. All patients underwent revision surgery with three sets of cultures obtained intra-operatively. Patients with significant intra-operative cultures were grouped into gram-positive and gram-negative culture cohorts. These patients were managed with a standardized protocol involving surgical debridement, nonunion site fixation, and culture-directed antibiotic treatment. Primary outcome was time to fracture union. Secondary outcomes included number of re-operations and eventual amputation or reconstructive surgery.

RESULTS

56 nonunion patients (10 %) were diagnosed with an infected nonunion (44 g-positive, 12 g-negative). Of these, 3 g-positive patients received an amputation or arthroplasty procedure prior to fracture union, and seven were lost to follow-up. There were no significant differences in age, gender, or nonunion site between cohorts. Most nonunions occurred in the lower extremity. The most common bacteria were staph species (54.3 %). 36 g-positive and 10 g-negative patients achieved fracture union. Time to union was on average 158.4 days longer in the gram-negative cohort-but did not reach statistical significance (446.8 days gram-positive, 662.3 days gram-negative, p = 0.69). There was no difference in re-operation rates (1.9 % gram-positive, 2.2 % gram-negative, p = 0.84).

CONCLUSIONS

Patients with infected nonunions had wide-ranging bacterial contamination that were treated successfully using a standardized protocol. However, patients with any gram-negative culture trended toward a delay in time to union.

Risk Factors for 30-Day Unplanned Re-Operation in Pediatric Upper Extremity Surgery: A National Surgical Quality Improvement Program (NSQIP)-Pediatric Analysis

Introduction The unplanned re-operation rate has been used as one marker of procedure quality in numerous surgical sub-fields. The purpose of this study was to determine independent risk factors for unplanned re-operations within 30 days following pediatric upper extremity surgery. Methods Pediatric patients who had a primary upper extremity procedure from 2012 to 2019 were identified in the National Surgical Quality Improvement Program-Pediatric database. The procedures included percutaneous fixation of supracondylar humerus fractures, open treatment of humeral condylar fractures, tendon sheath incision, repair of syndactyly, and reconstruction of polydactyly. Patients were categorized by those who had unplanned return to the operating room within 30 days and patients who did not. Patient demographics, clinical characteristics, and medical co-morbidities were evaluated for their association with re-operation using bivariate and multivariate analysis. Results A total of 27,536 pediatric patients underwent primary upper extremity surgeries; of these, 290 (1.1%) required an unplanned re-operation. After controlling for potential confounding variables on multivariable regression analysis, American Society of Anesthesiologists (ASA) class III-V (OR 15.89; p<0.001), inpatient procedure (OR 1.29; p=0.044), emergent/urgent triage (OR 3.75; p<0.001), longer operative time (OR 1.01; p<0.001), and prolonged hospital stay (OR 1.01; p=0.010) were independent predictors for re-operation. Conclusion This study demonstrates that the national rate of 30-day unplanned re-operation in pediatric upper extremity surgeries is low overall. The greatest risk factors for unplanned re-operation were ASA class III-V, inpatient setting, emergent/urgent triage, longer operative time, and prolonged hospital stay. This knowledge can help further improve patient outcomes through risk stratification and preoperative planning.

Hallmarks of peripheral nerve function in bone regeneration

Skeletal tissue is highly innervated. Although different types of nerves have been recently identified in the bone, the crosstalk between bone and nerves remains unclear. In this review, we outline the role of the peripheral nervous system (PNS) in bone regeneration following injury. We first introduce the conserved role of nerves in tissue regeneration in species ranging from amphibians to mammals. We then present the distribution of the PNS in the skeletal system under physiological conditions, fractures, or regeneration. Furthermore, we summarize the ways in which the PNS communicates with bone-lineage cells, the vasculature, and immune cells in the bone microenvironment. Based on this comprehensive and timely review, we conclude that the PNS regulates bone regeneration through neuropeptides or neurotransmitters and cells in the peripheral nerves. An in-depth understanding of the roles of peripheral nerves in bone regeneration will inform the development of new strategies based on bone-nerve crosstalk in promoting bone repair and regeneration.