Does Screw Order Matter? A Technique Tip to Prevent Loss of Fracture Reduction during Surgical Fixation of Lateral Malleolus Fractures.

When obtaining surgical fixation of lateral malleolus fractures, a cortical lag screw is commonly used to obtain anatomic reduction. Subsequently, a neutralization plate is applied. Slight loss of fracture reduction after plate placement occasionally occurs. Although this is frequently attributed to poor bone quality or suboptimal initial lag screw fixation, a frequently overlooked factor is screw order when applying the neutralization plate. The purpose of this technique tip is to highlight the biomechanical rationale behind this loss of reduction and advocate a specific screw order for lateral malleolus fixation.

Factors Associated With Implant Removal Following Plate-and-Screw Fixation of Isolated Metacarpal Fractures.

PURPOSE: The incidence of and associated risk factors for implant removal following the plate-and-screw fixation of metacarpal shaft fractures have not been well described. The primary objective of our study was to identify implant-related radiographic parameters associated with implant removal in patients treated with the plate-and-screw fixation of isolated, displaced metacarpal fractures at 2 years of follow-up. The secondary objective of our study was to identify patient-related factors associated with implant removal. METHODS: A retrospective study of all patients who underwent open treatment of a metacarpal fracture with a plate-and-screw construct from January 1, 2000, to April 30, 2019, at 2 level-1 trauma centers was conducted. After the application of exclusion criteria, we identified 138 patients with a single isolated metacarpal fracture of a nonthumb digit treated with open reduction and internal fixation using a plate-and-screw construct. Our study endpoint was the removal of the plate-and-screw construct or a minimum of 2 years of follow-up without the removal of the hardware. Twenty-three patients achieved our study endpoint as determined using their electronic medical records, and 58 additional patients were reached via telephone to confirm their implant removal status. A bivariate analysis was used to screen for factors associated with implant removal, and variables significant in the bivariate screen were included in a multivariable stepwise logistic regression model. RESULTS: Twenty-three out of 81 patients (28%) in our final cohort underwent implant removal by the final follow-up visit. In the logistic regression analysis, the distance between the plate and metacarpophalangeal joint, the distance between the plate and carpometacarpal joint, and active smoking were independently associated with implant removal. CONCLUSIONS: The proximity of metacarpal plates to adjacent joints is associated with subsequent implant removal. Patients may be counseled about the higher risk of implant removal when periarticular metacarpal plating is performed. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognosis IV.

Early Weight Bearing after Distal Femur Fracture Fixation.

OBJECTIVES: To assess outcomes following early weight bearing after distal femur fracture fixation with locked lateral plating. DESIGN: Retrospective cohort study. SETTING: Two Level 1 Academic Trauma Centers. PATIENTS/PARTICIPANTS: Patients 18 years and older with distal femur fractures treated with locked lateral plating. INTERVENTION: Early full weight bearing (defined as less than 30 days from date of surgery) versus restricted post-operative weight bearing. MAIN OUTCOME MEASUREMENTS: Composite complication comprising malunion, nonunion, surgical site infection, re-admission, or death. RESULTS: 270 distal femur fractures were reviewed, with 165 meeting inclusion criteria. 21 patients had been allowed early full weight bearing. Fractures were divided into two groups based on when full weight bearing was allowed post-operatively. The two groups had similar fractures as determined by the distribution of AO distal femur fracture and Su periprosthetic femur fracture classifications. The early weight bearing group was significantly older and more comorbid. Despite being older, more comorbid, and allowed early full weight bearing on their fracture fixation construct, there was no difference in the rate of composite complications between groups. CONCLUSION: Our data contributes to the small, but growing body of literature that has found no increased rate of fracture related complications in surgically treated distal femur fractures allowed early post-operative weight bearing. LEVEL OF EVIDENCE: Therapeutic Level III Study.

Hematoma Formation After Hip Corticosteroid Injection in a Patient with Chronic Myelomonocytic Leukemia: A Case Report.

CASE: We present a 70-year-old woman with history of chronic myelomonocytic leukemia with a right thigh hematoma after a corticosteroid hip injection. Aspiration of the hematoma was attempted, but she developed a significant transfusion requirement with paresthesias in a lateral femoral cutaneous nerve distribution, prompting transfer. Imaging demonstrated no active extravasation, and she was managed conservatively. At 8-month follow-up, she had a persistent consolidated hematoma on the right side, and she subsequently died of complications of her cancer. CONCLUSION: This case demonstrates an unusual complication from a common nonoperative modality, as well as important coagulopathies that must be considered in patients with leukemia.

Fixed (Congenital) Patellar Dislocation.

Congenital dislocation of the patella is a rare condition characterized by lateral dislocation of the patella that is irreducible without surgical correction. Although there is no clear inheritance pattern, it is associated with several congenital syndromes. Patients often demonstrate flexion contracture, loss of active knee extension, increased tibial external rotation, and absent patella in the trochlea. Treatment requires surgical management and is comprised of lateral release, medial stabilization, quadriceps lengthening, and distal realignment. Results are generally favorable after treatment; persistent flexion contracture and redislocation are the most common complications. Further study is needed to define the optimal timing and treatment strategy for this uncommon condition.

Duty cycling influences current generation in multi-anode environmental microbial fuel cells.

Improving microbial fuel cell (MFC) performance continues to be the subject of research, yet the role of operating conditions, specifically duty cycling, on MFC performance has been modestly addressed. We present a series of studies in which we use a 15-anode environmental MFC to explore how duty cycling (variations in the time an anode is connected) influences cumulative charge, current, and microbial composition. The data reveal particular switching intervals that result in the greatest time-normalized current. When disconnection times are sufficiently short, there is a striking decrease in current due to an increase in the overall electrode reaction resistance. This was observed over a number of whole cell potentials. Based on these results, we posit that replenishment of depleted electron donors within the biofilm and surrounding diffusion layer is necessary for maximum charge transfer, and that proton flux may be not limiting in the highly buffered aqueous phases that are common among environmental MFCs. Surprisingly, microbial diversity analyses found no discernible difference in gross community composition among duty cycling treatments, suggesting that duty cycling itself has little or no effect. Such duty cycling experiments are valuable in determining which factors govern performance of bioelectrochemical systems and might also be used to optimize field-deployed systems.