Rotational Stability of Proximally Unlocked Retrograde Femoral Nail In Damage Control Surgery – Biomechanical Study

BACKGROUND: This biomechanical study was performed to look into the rotational stability of retrograde femoral intramedullary nail when it is used without proximal locking as a damage control device for management of femoral shaft fractures in emergency situations. This study compares this technique with the accepted methods for femoral shaft fixations in damage control surgeries. An alternative technique of using lateral compression screw to provide additional rotational stability is described.METHODS: Experiments were divided into four different sets. Distally locked retrograde nail was passed across the fracture without any proximal fixation in set 1, a compression screw passed from lateral cortex in set 2, a proximal locking screw fixation in set 3. In set 4, Saw bone was fixed with external fixator.The lateral compression screw group was further sub divided into three subgroups based on the amount of torque applied manually.The torsion test was applied to create an rotational displacement of 10 degrees and the maximum load required to create the rotational displacement was noted.RESULTS: Application of a compression screw improved the rotational stability significantly in comparison to no proximal locking. In the subgroup III of lateral compression screw application, the rotational stability was found to be equivalent to stability achieved with Nail with proximal locking and was found to be greater in comparison to external fixator application.CONCLUSION: This study shows that the addition of a lateral compression screw significantly improves rotational stability and has the potential to be used in emergency lifesaving procedures.

Excessive Derotational K-Wire Angulation Decreases Compression by Headless Compression Screw

Background Scaphoid fracture is the most common carpal bone fracture. Open reduction internal fixation of scaphoid fractures typically undergo stabilization by a single headless compression screw (HCS). During screw insertion, a derotational Kirschner wire (K-wire) is often placed for rotational control of the near and far fragment. Questions/purposes The aim of this study was to determine if there is an angle of derotational K-wire placement in relation to the axis of a HCS that compromises the amount of compression generated at a fracture site by the HCS. We hypothesize that increased off-axis angle will lead to decreased compression across the fracture site. Methods A Cellular Block 20 rigid polyurethane foam (Sawbones, Vashon, WA) scaphoid model was created to eliminate variability in bone mineral density in cadaveric bone. MiniAcutrak HCS screws (Acumed, Hillsboro, OR) were used for testing. Three conditions were tested: (1) HCS with derotational wire inserted parallel to the HCS (zero degrees off-axis); (2) HCS with derotational wire inserted 10 degrees off-axis; and (3) HCS with derotational wire inserted 20 degrees off-axis. Results A statistically significant difference in the mean compression of the control group (56.9 N) was found between the mean compression with the derotational K-wire placed 20 degrees off-axis (15.2 N) (p = 0.001). Conclusions Compression at the fracture site could be impeded by placing an excessively angulated off-axis derotation wire prior to insertion of the HCS. Clinical Relevance Our study adds a new detail to the optimal technique of HCS placement in scaphoid fractures to improve compression and fracture union.

Physicochemical properties of extruded ready-to-eat snack from unripe plantain blends, pineapple by-products and stevia

The aim of this research was to evaluate the effect of extrusion temperature (ET 120 – 180 °C), feed moisture content (FMC 16 - 25 g/100 g), pineapple by-products proportion (PBP) (0 - 30 g/100 g) in the unripe plantain flour, and the stevia content (STC 0 - 5 g/100 g) on the physicochemical properties and sensory acceptance of ready-to-eat extruded snacks, through a central compound design, using a single-screw extruder with a compression screw ratio of 3:1. The results were analyzed by response surface. The increase in FMC, PBP and STC decreased (p < 0.05) the expansion index (EI). The increase in ET decreased (p < 0.05) the apparent density (AD), water absorption index (WAI), water solubility index (WSI) and total color difference (ΔE). The increase in FMC decreases EI, WAI, and increase AD and WSI (p < 0.05). The Increase in PBP decreased EI, WSI, and increase AD, hardness (H) and ΔE (p < 0.05). The increase in STC decreased (p < 0.05) EI, and increase AD and H. The treatments with greater general acceptability were those that contained 15 and 30 g/100 g of PBP and STC 2.5 g/100 g, and they were obtained at ET 150ºC and 20.5 g/100 g of FMC, without affecting the physicochemical properties.

Compression Screw Fixation of Lunate Fracture: Case Report and Review of the Literature

Background Isolated traumatic lunate fractures without other surgical carpal bone or ligamentous injuries are extremely rare, with few published reports available to guide management. Lunate fracture management is controversial, and depends on concurrent injuries of adjacent carpal bones, ligaments, risk of ischemia, and displacement. Case Description A 48-year-old right hand dominant man suffered a crush injury to the left hand caught between a forklift and a metal shelf. Radiographs and computed tomography imaging of the left hand and wrist were significant for a displaced Teisen IV fracture of the lunate. A dorsal ligament sparing approach was utilized to access, reduce, and fixate the fracture using a headless compression screw. After immobilization and rehab, at 9 months after initial injury, the patient was back to work on full duty without restriction and pleased with the results of his treatment. Literature Review A literature review of lunate fracture compression screw fixation was performed and revealed a total of three reports indicating successful treatment of fractures, with patients returning to full activity. Clinical Relevance Lunate fractures are rare, often missed, and treating these injuries can be challenging, particularly in the setting of acute trauma. Based on our limited experience, we believe that open reduction and internal fixation of isolated Teisen IV lunate fractures with a headless compression screw is a viable treatment modality with satisfactory outcomes.

Comparison of 4 Different Fixation Strategies for Midfoot Arthrodesis: A Retrospective Comparative Study

Background Midfoot arthrodesis is a common procedure performed both for arthritis and correction of deformity. The optimal fixation for midfoot arthrodesis has not been established, though numerous studies have been investigating the fixation techniques of midfoot arthrodesis. The purpose of this study was to compare the union rate of midfoot arthrodesis using 4 different fixation strategies and investigate risk factors of nonunion following midfoot arthrodesis. Methods A retrospective chart review was performed for patients who underwent midfoot joint arthrodesis between January 2014 and May 2019. The rates of nonunion and postoperative complication were compared among 4 different fixation constructs: staple fixation, compression plate fixation, compression plate with lag screw fixation, and compression screw fixation. Predictors of nonunion following midfoot arthrodesis were investigated through a multivariable logistic regression analysis. A total of 95 patients (99 feet), including 240 midfoot joints were included in this study. The mean follow-up period was 78.4 weeks. Results Overall, bony union was achieved in 86 out of 99 (86.9%) patients, which included 218 out of 240 (90.8%) midfoot joints. A significant difference in the nonunion rate according to the type of fixation construct was found ( P = .011); the compression screw alone fixation construct was noted to have a significantly higher nonunion rate than other fixation constructs. Diabetes mellitus (odds ratio [OR] = 0.179 [95% CI: 0.059, 0.542]), the type of fixation construct (compression screw alone; OR =1.789 [95% CI: 1.071, 2.978]), lack of adjuvant bone graft (OR = 2.803 [95% CI: 1.081, 7.268], and postoperative nonanatomical alignment (OR = 3.937 [95% CI: 1.278, 12.126]) were identified as independent predictors of nonunion following midfoot arthrodesis. Conclusion The rate of nonunion following midfoot arthrodesis among 4 different commonly used fixation constructs was compared in this study. Risk factors of nonunion were investigated revealing that diabetes mellitus, compression screw fixation alone, lack of adjuvant bone graft, and postoperative nonanatomical alignment are independent predictors of nonunion following midfoot arthrodesis. Levels of Evidence: Level III: Comparative cohort study

Safety and Efficacy of Medial Plate in First Metatarsophalangeal Joint Arthrodesis

Background. Arthrodesis of the first metatarsophalangeal joint (MTP-1) is a recognized and effective procedure in advanced osteoarthritis of this joint. Fixation with a dorsal plate and a compression screw has been described as the most stable. Nevertheless, the frequency of revision procedures after MTP-1 arthrodesis has been reported to exceed 10% in some reports. The need for revision surgery is mostly related to the fixation material used and concern both its destabilization and a conflict between the implants and soft tissues. Therefore, there is still scope for developing new stabilization methods for the MTP-1 joint. Materials and methods. With the approval of the relevant Bioethics Committee, we conducted a pilot clinical trial to assess the safety and efficacy of the use of the medial plate in MTP-1 fusion. Twenty patients qualified for treatment due to osteoarthritis of the metatarsophalangeal joint were evaluated. The clinical results of the surgical treatment were assessed at least one year after the surgery. Results. The mean AOFAS MTP-IP score increased from 35.29±18.76 to 75.59±12.15. The mean EFAS score in­creased from 9.24±5.73 to 18.35±5.66. Pain level as per a VAS decreased from 6.24±1.48 to 1.59±2.58. A total of 18 patients were satisfied with the procedure, with the remaining 2 patients reporting the result as unsatisfactory. Two revision procedures were performed, both due to migration of the fixation material. Conclusions. 1. The clinical results of MTP-1 arthrodesis with the medial plate are comparable to the results in the litera­ture. 2. It can be concluded that the use of the medial plate in arthrodesis of the MTP-1 joint is safe and effective, and is a va­­luable alternative to existing methods.