A biomechanical approach to distal radius fractures for the emergency radiologist

Evaluating the biomechanical performance of Ti6Al4V volar plates in patients with distal radius fractures

Purpose: This study aimed to investigate the biomechanical performance of three Ti6Al4V volar plates with the latest designs using a finite element model. Methods: An AO type 23-A3 distal radius fracture and the models of T plate (2.4 mm LCP Volar Distal Radius Plate), V plate (2.4 mm LCP Two-Column Volar Distal Radius Plate) and π Plate (2.4 mm Volar Rim Distal Radius Plate) (all from Depuy Synthes, West Chester, PA, USA, Ti6Al4V) were built in 3D-matic software. After assembling the internal fixation and fractures, we imported these models into the finite element analysis software (ABAQUS). An axial loading of 100 N was added to the distal end of each model. The displacements of total models and implants, the principal strains and the von Mises stresses in the plates were calculated and compared to capture the biomechanical features of the three plates. Results: The T plate, V plate and π plate represented a model displacement of 0.8414 mm, 1.134 mm and 1.936 mm, respectively. The T plate was with the implant displacement of 0.7576 mm, followed by the V plate (0.8802 mm) and the π plate (1.545 mm). The T plate had the smallest principal strain of 0.23%, the V plate showed an intermediate level of 0.28%, and the π plate had a value of 0.72%. The least peak von Mises stress was observed in the V plate with 263.6MPa, and this value was 435.6 MPa and 1050 MPa in the T plate and π plate, respectively. Conclusion: The biomechanical features of three Ti6Al4V volar locking plates in an AO type 23-A3 fracture were described in our analysis. The T plate and the V plate showed similar biomechanical performance while the π plate represented worse performance than the other two plates.

Relationship Between Carpal Bone Morphology and Distal Radius Fracture Pattern

Abstract Background: In this study, we examined whether carpal bones (lunate, hamate, capitate) morphologies and fourth metecarp-capitate articulation have an effect on the distal radius fracture pattern. Methods: 206 patients who applied to the emergency department with distal radius fracture between 2016-2020 were included in the study. Preoperative and pre-reduction x-ray films of the patients were examined. Lunate, hamate, capitate morphologies and 4.metacarp articulation analyzed and classified. Distal radius fracture types were classified according to AO and Fernandez. The relationship between carpal bone morphology and distal radius fracture type was analyzed. Results: This study consisted of 101 men and 103 women. AO fracture types and carpal bone morphologies (lunate joint type according to Viegas, lunate type according to Zapico, capitate morphology, hamate morphology and capitate-4 metacarpal joint morphology) did not differ significantly (p > 0.05). Fernandez fracture types and carpal bone morphologies (lunate joint type according to Viegas, lunate type according to Zapico, capitate morphology, hamatum morphology and capitate-4.metacarp joint morphology) were compared, there was no significant difference (p > 0.05). Conclusion: As a result, no clear relationship could be demonstrated between carpal bone morphology and distal radius fracture pattern.

Recognizing Isolated Ulnar Fractures as Potential Markers for Intimate Partner Violence

PURPOSE

This study aimed to assess the incidence of intimate partner violence (IPV) in women with isolated ulnar fractures and compare the injury characteristics in victims of IPV with those who sustained the same fractures due to other causes.

METHODS

Electronic health records from three level I trauma centers were queried to identify a cohort of women, aged 18 to 50, sustaining isolated ulnar fractures from 2005 to 2019. Radiographs were reviewed for fracture location, comminution, and displacement. Demographic data, number of visits to the emergency department, and documentation of IPV were also collected. Patients were stratified into four groups based on clinical chart review: confirmed IPV, possible IPV, not suspected for IPV, and not IPV. Historical imaging analysis for IPV prediction was also performed.

RESULTS

There were 62 patients, with a mean age of 31 years (IPV: 12 confirmed, 8 possible, 8 suspected not IPV, 34 confirmed not IPV). Comparative analysis with and without suspected cases demonstrated IPV to be associated with nondisplaced fractures (95% versus 43%; P < .001 and 91% versus 44%; P = .012). Confirmed cases were also associated with homelessness (46% versus 0%; P < .001), and the number of documented emergency department visits (median 7.0; interquartile range 2.0-12.8 versus 1.0; interquartile range 1.0-2.0; P < .001). Formal documentation of IPV evaluation was completed in only 14 of 62 (22.5%) patients. Historical imaging analysis predicted IPV in 8 of 12 (75%) confirmed IPV cases.

CONCLUSION

Up to one-third of adult women sustaining isolated ulnar fractures may be the victims of IPV. Lack of displacement on radiographs, frequent emergency department visits, and homelessness would favor IPV etiology.

Application of 3D-printed and patient-specific cast for the treatment of distal radius fractures: initial experience

BACKGROUND

Distal radius fracture is common in the general population. Fracture management includes a plaster cast, splint and synthetic material cast to immobilise the injured arm. Casting complications are common in those conventional casting technologies. 3D printing technology is a rapidly increasing application in rehabilitation. However, there is no clinical study investigating the application of a 3D-printed orthopaedic cast for the treatment of bone fractures. We have developed a patient-specific casting technology fabricated by 3D printing. This pioneering study aims to use 3D-printed casts we developed for the treatment of distal radius fractures, to provide the foundation for conducting additional clinical trials, and to perform clinical assessments.

METHOD

Ten patients with ages between 5 and 78 years are involved in the clinical trial. Patients are applied 3D-printed casts we developed. Orthopaedic surgeons carried out a six-week follow-up to examine clinical outcomes. Two questionnaires were developed for the assessment of clinical efficacy and patients' satisfaction. These questionnaires are completed by physicians and participating patients.

RESULTS

A 3D-printed cast creates a custom-fitted design to maintain the fractured bone alignment. No loss of reduction is found in all patients. Compartment syndrome and pressure sores are not present. Patient comfort gets positive scores on the questionnaire. All (100%) of the patients opt for the 3D-printed cast instead of the conventional plaster cast.

DISCUSSION

A patient-specific, 3D-printed cast offers a proper fit to immobilise an injured arm and holds the fracture reduction appropriately. A custom-fitted structure reduces the risk of pressure-related complications due to the high and concentrated local stress. The ventilated and lightweight design minimises interference with a patient's daily activities and reduces the risk of cutaneous complications. Patients express a strong preference for using a 3D-printed cast instead of a plaster cast. Limitations of the novel cast include a slight odour after heavy sweating and the relatively high cost due to the limitations of current 3D printing technologies.

CONCLUSIONS

This pioneering study is the first clinical trial on the application of a 3D-printed cast for the treatment of forearm fractures. The novel casting technology heals the fracture effectively without casting complications. The 3D-printed cast is patient-specific and ventilated as well as lightweight, and it features both increased patient comfort and satisfaction.

[Distal radius fracture of the adult : Diagnostics and therapy]

Fractures of the distal radius are very common. The majority of patients are elderly females. High impact trauma are often responsible for fractures in young men. Clinical and radiological diagnostics, including computer-assisted tomography (CAT) scan, are generally sufficient. The indication for conservative treatment is still recommended for specific fracture patterns. Application of palmar locking plates after open reduction proved to be efficacious for the majority of fracture patterns. Furthermore, precise detection and treatment of concomitant lesions are mandatory in order to prevent complications.

A preliminary exploration of ulnar variance in healthy wrists at a tertiary hospital in Jeddah

Objectives:

To gain preliminary insight by exploring ulnar variance changes in a Saudi-based sample.

Methods:

This 6-month (December 2013 to June 2014) cross-sectional study was conducted on a randomly selected healthy adult volunteers with a sample size of 104, at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Posteroanterior (PA), anteroposterior (AP), and PA grip views are taken. The variables of interest were the PA, AP, and PA fist measurements of both right and left wrists. An independent t-test was used to compare means between groups.

Results:

A total of 104 volunteers were recruited. Among 17 participants who had a negative ulnar variance on right PA views, a significantly high proportion (n=9; 56.2%) maintained a negative value on fist views; 7 participants (43.8%) had a neutral ulnar variance while none (0%) had a positive value (p<0.001). Similarly, a significant proportion of participants who had neutral, or positive values on right PA views maintained the same values on right fist views (p<0.001). On radiographs of the right wrist, the ulnar variance decreased with a change in wrist position, with an absolute difference in magnitude of 2.13 (p<0.001) between PA and AP views. Similarly, the ulnar variance on the left side decreased significantly between PA and AP views (absolute difference in magnitude, 1.68; p<0.001).

Conclusions:

Ulnar variance changes in our sample are similar to what is reported in the literature.