Treatment of a Ballistic Radius Fracture with Segmental Bone Loss Using the Masquelet Technique in a Child: A Case Report.

CASE: A 4-year-old boy sustained an accidental self-inflicted gunshot wound to the left forearm. Radiographs revealed a comminuted mid-diaphyseal ballistic radius fracture with a critical-sized bone defect. The fracture was treated with the placement of a flexible intramedullary nail and antibiotic cement spacer, followed by second-stage bone grafting and open reduction and internal fixation of the radius 6 weeks later. Four months after the second-stage procedure, the radial defect healed appropriately without complications. CONCLUSION: In this case of a pediatric comminuted mid-diaphyseal radius fracture with bone loss, the induced membrane technique resulted in healing across a critical-sized bone defect.

Topical Antibiotic Powder and Nonunion Risk in Surgically Treated Tibial Plateau and Pilon Fractures.

INTRODUCTION: High-energy periarticular tibia fractures are challenging injuries with a significant risk of complications. Postoperative infection rates, although improved, remain unacceptable. Intrawound topical antibiotic (TA) application has been popularized to reduce postoperative infections. Although TA may minimize infections, it remains unclear whether TAs have any impact on the development of nonunion. Recent investigations of TA use in fracture care have questioned its efficacy in vivo and suggested a potentially deleterious effect on fracture healing. This study investigates the impact of TA on nonunion rates in surgically treated high-energy periarticular tibia fractures. METHODS: Retrospective analysis of surgically treated periarticular tibia fractures at a single Level 1 trauma center was conducted. Intervention in question was the clinical effect of intrawound TA powder application at definitive closure. A total of 222 high-energy periarticular tibia fractures were included, 114 with TA use and 108 without. The primary outcome was the occurrence of nonunion, with secondary outcomes being superficial and deep postoperative surgical site infections. RESULTS: Twenty-seven patients (12.1%) were diagnosed with nonunions (14 pilons and 13 plateaus). There was no statistically significant difference in nonunion rates among patients who received topical antibiotics (15.8%) versus the group of patients who did not (8.3%) ( P = 0.23). Odds of developing nonunion was significant for open injuries (odds ratio 6.16, P < 0.001) and patients with a provisional external fixator (odds ratio 8.72, P = 0.03) before definitive fixation. No notable difference in the number of superficial and deep infections was identified between groups. CONCLUSION: The use of TA in high-energy periarticular tibia fractures showed no statistically significant increase in nonunion rates but did not conclusively rule out nonunion as a possible effect of intrawound TA. Additional large-scale multicenter prospective studies are needed to confirm these findings. The current body of literature regarding high-energy periarticular tibia fractures does suggest that TAs lower the risk of postoperative infections, but the nonunion risk remains unclear. LEVEL OF EVIDENCE: Level III, Retrospective Cohort Study.

Dynamics of data-driven microstates in bipolar disorder.

Many of the existing models of mood in bipolar disorder can largely be divided into two camps, tracking mood as either a discrete or continuous variable. Both groups rely upon certain assumptions, with most considering only aggregate scores on clinical instruments. In this study, we propose a novel framework that combines elements from both discrete and continuous mood models, using a machine learning pipeline to detect subtle patterns across individuals. Latent factors are constructed from assessments at the item level, then clustered into groups referred to as microstates. Transitions between microstates are captured via a discrete-time Markov chain, allowing for characterization of mood's dynamic nature. Key findings include a factor mapping heavily onto irritability and aggression, as well as a hierarchical pattern of microstates within depression and mania. Validity of these results is confirmed by reproduction in an unseen data set from a separate subject cohort.

Intramedullary Nail for a Distal Tibia Fracture.

Extraarticular fractures of the distal tibia have historically been treated with open reduction and fixation with plates and screws. This technique requires a more extensive dissection and comes with a higher risk of wound complications than intramedullary nail fixation. This article and the accompanying video demonstrate the use of closed reduction and suprapatellar nail fixation appropriate for the treatment of most extraarticular distal tibial fractures. A variety of treatment decisions are discussed, including the nail insertion method, fixation of associated fibular fractures, and postoperative immobilization.

Vertical Shear Pelvic Ring Injury Adjacent to Retained Pelvic Hardware: A Case Report.

CASE: A 47-year-old obese woman presented with a vertical shear (VS) pelvic ring injury after a motor vehicle accident around her previous posterior pelvic hardware. The patient underwent closed reduction with percutaneous posterior screw fixation using combined fluoroscopy and O-arm (Medtronic). CONCLUSION: A rare case of VS pelvic injury with indwelling posterior pelvic hardware does not automatically preclude placement of percutaneous sacroiliac and transiliac-transsacral screws. Combining fluoroscopic imaging and O-arm enables safe screw placement, saving patients from invasive surgeries.

Comparison of reamed long and short intramedullary nail constructs in unstable intertrochanteric femur fractures: A biomechanical study.

OBJECTIVES: There is no definitive evidence to guide clinicians in their decision-making for implant choice regarding long or short intramedullary nails for unstable fracture patterns. Historically short nails were associated with higher rates of perisprothetic fractures which seem to have improved with newer designs. Long intramedullary nails have higher blood loss and time under anesthesia. The purpose of this study was to assess stability of long and short intramedullary nail constructs in unstable intertrochanteric fracture patterns to better elucidate if unstable intertrochanteric fractures are amenable to treatment with short intramedullary nails. METHODS: This study utilized composite model femurs which were assigned to either a comminuted or reverse obliquity fracture pattern, then subsequently assigned to implantation with either a long or short intramedullary nail. All the samples were reamed to the level of the distal femur and instrumented with the appropriate nail. Axial and torsional stiffness as well as axial load to failure values were determined using a servohydraulic loading system. RESULTS: Short nail constructs exhibited significantly greater axial stiffness in A1 fractures and torsional stiffness in A3 fractures when compared with long nails. There was no significant difference between axial load to failure between long nails and short nails. DISCUSSION: We found no significant difference in axial load to failure values between long and short intramedullary nail fixation in 2 unstable intertrochanteric fracture patterns in a composite femur model. Short nails exhibited greater stiffness in axial loads in the A1 pattern and torsional stiffness in the A3 pattern. This suggests short or long intramedullary nails could be appropriately employed for fixation of unstable intertrochanteric hip fracture patterns.

Examination Under Anesthesia for Evaluation of Hip Stability in Posterior Wall Acetabulum Fractures.

Posterior wall fractures of the acetabulum are the most common acetabular fracture pattern. Stable, congruous hips are amenable to nonoperative management, whereas any instability in the hip is an indication for operative management of the posterior wall fracture. Stability cannot adequately be predicted by static imaging alone. Therefore, the dynamic stress examination under anesthesia remains the gold standard in determining hip stability to guide treatment. This case-based video demonstrates a systematic technique for performing an examination under anesthesia and explains how to interpret the fluoroscopic imaging to differentiate stable and unstable hips.

Autologous Bone Graft Harvest Using the Reamer-Irrigator-Aspirator.

Initially developed to reduce intramedullary pressures during long bone intramedullary nail placement, the reamer-irrigator-aspirator (RIA) can be used to harvest large volume autologous bone graft from the intramedullary canal of a long bone. This case-based surgical technique video demonstrates the appropriate techniques that should be applied while using the RIA to obtain autologous bone graft from the femur. A large volume of bone graft, generally between 30 and 90 cm, can be obtained using a single RIA procedure. The bone graft harvested from the intramedullary canal is excellent regarding its biochemical properties, with several studies reporting higher levels of growth factors and stem cells when compared with iliac crest bone graft. Surgical technique is key to maximize bone graft harvest, as well as to avoid complications including iatrogenic fracture, intraarticular penetration, and fragmentation of either the reamer head from the drive shaft or the guide wire. Pearls and pitfalls regarding sizing of the reamer head, determination of starting point, guide wire placement, reamer advancement, and diligent use of fluoroscopic imaging are highlighted during this video. Finally, outcomes regarding healing of long bone defects when using RIA-derived autologous bone graft and reduction in postoperative pain at the graft donor site are briefly reviewed.

Scientific Understanding of the Induced Membrane Technique: Current Status and Future Directions.

OBJECTIVES: To review the most recent basic science advances made in relation to the induced membrane technique and how those relate to clinical practice, applications, and future research directions. DESIGN: Review of the literature. SETTING: Any trauma center which might encounter large segmental bone defects. ARTICLES REVIEWED: Basic science articles that looked at characteristics of the induced membrane published in the past 30 years. INTERVENTION: None.

Incarcerated fracture fragments of Longevity polyethylene liners after total hip arthroplasty.

Highly cross-linked polyethylene liners are widely used in total hip arthroplasty because they experience lower wear rates than conventional polyethylene liners. However, the cross-linking process does decrease the resistance of polyethylene to fatigue failure and fracture. This report describes 2 cases of highly cross-linked polyethylene liner fracture occurring in association with hip dislocation and unsuccessful closed reduction consequent to blockage by an incarcerated liner fragment. These cases highlight the known polyethylene fracture risk factors of thin and unsupported polyethylene and large bearing sizes. They also reinforce the importance of a careful evaluation of postreduction radiographs for the presence of a concentric reduction and provide a possible explanation for postoperative hip instability, multiple dislocations, and incomplete seating of the femoral head on attempts at closed reduction.

Multiple macroenzymes in a patient with AIDS: diagnosis using ultrafiltration.

OBJECTIVES: Multiple immunoglobulin-bound enzymes (macroenzymes) are reported for the first time in an individual with AIDS. Possible causes and suitable methods of detection are addressed. METHODS: An asymptomatic man with a history of AIDS with hypergammaglobulinemia and elevated creatine kinase, amylase, and liver enzyme concentrations was evaluated before enrollment in a clinical trial. Macroenzymes were considered a possible source of these elevated concentrations. RESULTS: Polyethylene glycol (PEG) precipitation and ultrafiltration (UF) were used to evaluate the presence of seven macroenzymes. PEG results suggested the presence of six of seven macroenzymes tested, while UF revealed three. UF results supported the clinical presentation. CONCLUSIONS: A previous report shows that in cases of excess immunoglobulin, PEG coprecipitates monomeric enzymes along with serum globulins, causing false-positive reporting of macroenzymes. This may explain the discrepancy between PEG and UF results in the presence of hypergammaglobulinemia, making UF a better method of detection in these circumstances.