Stacked 1/3 Tubular Plates for Fixation of Pediatric Forearm Fractures: A Biomechanical Study.

Introduction: Among operatively treated pediatric forearm fractures, many different fixation constructs are described. The goal of this study was to define the biomechanical properties of a double stacked 1/3 tubular plate construct used by the senior author for some fractures and to review available literature regarding the use of stacked plates. Methods: Biomechanical testing was performed by 4-point bending of three different plate constructs: 1/3 tubular plate, stacked 1/3 tubular plates, and 2.7 mm LC-DCP plate. Five test specimens were evaluated for each of the three plate constructs. From stress-strain curves, flexural stiffness (N/mm), force to cause plastic deformation (N), and force to cause 10° bend (N) were calculated and compared using standard t-test statistics. Results: Key outcome parameter means (± SD) for the three plate constructs (1/3 tubular plate, stacked 1/3 tubular plates, and 2.7 mm LC-DCP plate) were reported respectively as follows: flexural stiffness (55.4 ± 3.5 N/mm, 131.7 ± 3.5 N/mm, 113.3 ± 12.1 N/mm), force to cause plastic deformation (113.6 ± 11.0 N, 242.1 ± 13.0 N, 192.2 ± 17.9 N), and force to cause a 10° bend (140.0 ± 8.4 N, 299.4 ± 14.1 N, 265.5 ± 21.2 N). Mean values of all three measures were significantly larger for the stacked 1/3 tubular plates than for the other plate constructs. Conclusions: The stacked 1/3 tubular plate construct was biomechanically superior to the other plate constructs tested. Stacked plating significantly improved stiffness of the fracture fixation construct supporting the use of this technique in selected trauma cases.

Cut Cortical Screw Purchase in Diaphyseal Bone: A Biomedical Study.

Introduction: During fracture osteosynthesis, traumatologists may remove screws which are too long, cut the excess length from the screw tip, then reinsert the cut screw (CS) to minimize implant waste. The purpose of this study was to determine if this practice influences screw purchase. Methods: Using an axial-torsion load device, the maximal insertion torque (MIT) required to insert 3.5 mm stainless steel cortical screws into normal and osteoporotic bone models was measured. MIT was determined in three different test conditions: (1) long screw (LS) insertion; (2) LS insertion, removal, and insertion of a normal-length screw (NS); and, (3) LS insertion, removal, cutting excess length from the screw tip, and reinserting the CS. Results: In the normal bone model, mean (± SD) MIT of LS insertion was 546 ± 6 Newton-centimeters (N-cm) compared to 496 ± 61 N-cm for NS reinsertion and 465 ± 69 N-cm for CS reinsertion. In the osteoporotic bone model, MIT of LS insertion was 110 ± 11 N-cm, whereas the values for NS and CS reinsertions were 98 ± 9 N-cm and 101 ± 12 N-cm, respectively. There was no significant difference in MIT between CS and NS reinsertions in the osteoporotic bone analog. Conclusions: Cutting excess length from a 3.5 mm stainless steel cortical screw did not decrease its purchase regardless of bone density. During osteosynthesis, orthopaedists may remove screws which are too long, cut the screw tip, and reinsert the shortened screw as a cost-saving measure without compromising fracture fixation.

Comparative Analysis of Topical Versus Intravenous Administration of Epsilon-Aminocaproic Acid on Blood Management in Total Knee Arthroplasty.

Introduction: Although the use of antifibrinolytics to reduce perioperative blood loss during total knee arthroplasty (TKA) has shown unequivocal benefit in regard to blood conservation, the best route of administration remains in question. This study tested the hypothesis that topical delivery of epsilon-aminocaproic acid (EACA) was superior to intravenous (IV) administration in the setting of primary TKA. Methods: This cross-sectional study included a six-year retrospective chart review of TKA patients done by a single surgeon. Post-operative hemoglobin levels and the incidence of blood transfusions were compared among three patient subgroups: no EACA, topical EACA, or IV EACA. Key outcome measures included post-operative hemoglobin, need for post-operative transfusion, and length of hospital stay. Results: Of the 668 patients included in this study, 351 (52.5%) received IV EACA, 298 (44.6%) received topical EACA, and 19 (2.8%) received no EACA. For the three-way comparisons, significant differences were observed for post-operative mean hemoglobin on day one (p < 0.001), day two (p < 0.001), and day three (p = 0.004), with consistently higher means for participants in the topical group. Eight patients required transfusions in the IV EACA group, but none were needed in the topical EACA group (p = 0.027). Length of stay was shortest for patients in the topical group, with 66% hospitalized for two days, while 84% of the IV group remained hospitalized for three days (p < 0.001). Conclusions: The topical delivery of EACA is superior to IV administration with respect to blood conservation for patients undergoing primary TKA.

Early Versus Delayed Mobilization Post-Operative Protocols for Primary Lateral Ankle Ligament Reconstruction: A Systematic Review and Meta-Analysis.

INTRODUCTION: Lateral ankle instability represents a common orthopaedic diagnosis. Nonoperative treatment through focused physical therapy provides satisfactory results in most patients. However, some patients experience persistent chronic lateral ankle instability despite appropriate nonoperative treatment. These patients may require stabilization, which can include primary lateral ligament reconstruction with a graft to restore ankle stability. Optimal post-operative rehabilitation of lateral ankle ligament reconstruction remains unknown, as surgeons vary in how long they immobilize their patients post-operatively. The aim of this review was to provide insight into early mobilization (EM) versus delayed mobilization (DM) post-operative protocols in patients undergoing primary lateral ankle ligament reconstructions to determine if an optimal evidence-based post-operative rehabilitation protocol exists in the literature. METHODS: Following PRIMSA criteria, a systematic review/meta-analysis using the PubMed/Ovid Medline database was performed (10/11/1947 - 1/28/2020). Manuscripts that were duplicates, non-lateral ligament repair, biomechanical, and non-English language were excluded. Protocols were reviewed and divided into two categories: early mobilization (within three weeks of surgery) and delayed mobilization (after three weeks of surgery). Functional outcome scores (American Orthopedic Foot and Ankle Society Score (AOFAS), Karlsson scores), radiographic measurements (anterior drawer, talar tilt), and complications were evaluated using weighted mean differences (pre- and post-operative scores) and mixed-effect models. RESULTS: After our search, twelve out of 1,574 studies met the criteria for the final analysis, representing 399 patients undergoing lateral ankle reconstruction. Using weighted mean differences the DM group showed superior AOFAS functional scores compared to the EM group (28.0 (5.5) vs. 26.3 (0.0), respectively; p < 0.001), although sample size was small. Conversely, no significant differences were found for Karlsson functional score (p = 0.246). With regards to radiographic outcome, no significant differences were observed; anterior drawer was p = 0.244 and talar tilt was p = 0.937. A meta-analysis using mixed-effects models confirmed these results, although heterogeneity was high. CONCLUSIONS: While there are some conflicting results, the findings indicated the timing of post-operative mobilization made no difference in functional outcomes or post-operative stability for patients undergoing lateral ankle ligament reconstruction. Because heterogeneity was high, future studies are needed to evaluate these protocols in less diverse patient groups and/or more consistent techniques for lateral ankle ligament reconstruction.

Enhancing Splinting Confidence through Inter-Residency Education: An Educational Workshop.

INTRODUCTION: The initial treatment for many orthopaedic injuries is splinting. Unfortunately, formal musculoskeletal training is limited in primary care leading to deficiencies in competency and confidence. Suboptimal splints can result in complications such as skin break-down, worsening of deformity, and increased pain. Our orthopaedic surgery clinic often cares for patients who initially present to an emergency department or primary care clinic for their orthopaedic injury. Previous studies have shown that a high number of splints are applied improperly in the primary care setting, which could result in in avoidable skin complications and fracture instability. METHODS: Orthopaedic surgery residents held a splinting workshop for family medicine residents. The workshop involved didactic and skills portions. Pre- and post-surveys were administered using a 10-point scale to assess confidence in applying three common splints. The data were analyzed using student's t-test and qualitative feed-back. RESULTS: Confidence in applying and molding each splint type improved significantly (p < 0.05). Knowledge in splint construction improved significantly as well (p < 0.05). Subjective feedback was positive. CONCLUSION: These results showed inter-residency education can increase residents' confidence in skill-based medical care significantly. The results are encouraging and should facilitate further collaboration between multispecialty residency programs to improve patient care. Further investigation is needed to determine how well skills gained in workshop are retained.

Near-simultaneous bilateral reverse total shoulder arthroplasty for the treatment of bilateral fracture dislocations of the shoulder.

A man in his mid-80s presented with bilateral posterior fracture dislocations of the humerus after suffering a seizure. He had Parskinson's disease and lived with his wife at home. His left shoulder was not felt to be reconstructable. The initial treatment plan was to perform reverse total shoulder arthroplasty (rTSA) on the left and non-operatively reduce his right shoulder. A left rTSA was performed, but his right shoulder was unstable due to a glenoid fracture and soft tissue instability. In order to preserve the patient's quality of life, a right rTSA was performed 4 days later. In the follow-up period, the patient was able to regain enough pain-free range of motion on activities of daily living. The patient died from complications of Parkinson's disease 10 months postoperatively.

Effect of Ultrasound Frequency and Treatment Duration on Antibiotic Elution from Polymethylmethacrylate Bone Cement.

INTRODUCTION: The objective of this study was to evaluate the effect of ultrasound frequency and treatment duration on antibiotic-impregnated polymethylmethacrylate (PMMA) antibiotic elution rates and mechanical strength. METHODS: Two batches of PMMA were prepared: one with five grams of vancomycin powder and one without. Each batch was divided into two frequency groups: kHz and MHz. Each frequency group was divided into two duration groups: two minutes and ten minutes. Elution samples were measured daily using flow injection analysis. After one week of elution, ultrasound treatments were done daily until each group's average concentration fell below those of non-ultrasound control groups. After elution testing, compression testing determined mechanical properties. Paired t-tests were used to compare daily elution amounts to baseline values. Univariate ANOVAs were used to test for effects of both frequency and treatment duration on antibiotic elution amounts and on mechanical properties. RESULTS: All ultrasound treatments resulted in significant increases in antibiotic elution. Frequency and duration had significant effects of increasing antibiotic elution (p < 0.001). The kHz group produced significantly greater antibiotic elution than the MHz group (p < 0.001). The 10-minute duration produced significantly greater antibiotic elution than the two-minute duration (both p < 0.001). Frequency and duration did not have significant effects on yield stress (p = 0.841 and p = 0.179, respectively). Frequency had a significant effect (p = 0.024) on modulus, but duration did not (p = 0.136). CONCLUSIONS: Ultrasound frequency and treatment duration significantly affect antibiotic elution from PMMA which may be helpful for treatment of periprosthetic joint infections during revision arthroplasty.