Anatomical features of the proximal end of the radius and its implications for implant design.

PURPOSE: The proximal radio-ulnar joint allows supination and pronation of the forearm and the humeroradial joint allows flexion and extension movements at the elbow joint. Although the proximal end of the radius is less common than other fractures, it is more common nowadays due to the prolongation of life expectancy, increased incidence of osteoporosis. There have been reports in the literature that success has not been achieved due to the lack of anatomical fit of the prosthesis. Knowledge of the morphometric features of the proximal end of the radius is important for the design of anatomically and biomechanically appropriate prostheses. METHODS: In this study, measurements of head and neck of radius, and radial tuberosity were measured in 80 dry radii. Parameters important for prosthesis design were analysed and their correlations examined. RESULTS: The shapes of radial head was found 36% oval and 64% circular. The mean heights of the radial head at anterior, posterior, medial, and lateral sides were 8.52 ± 1.32 mm, 9.02 ± 1.23 mm, 9.20 ± 1.59 mm, 8.05 ± 1.13 mm, respectively. The mean depth of articular facet were 1.85 ± 0.37 mm. It was determined that there was no high correlation between the parameters affecting the prosthesis design. CONCLUSIONS: Morphological and morphometric features of the proximal radius are important for prosthesis design and implantation. The ideal radial head prosthesis design is challenging due to numerous parameters, wide ranges and low correlation, although modular designs facilitate compatibility. The widespread use of 3D printing technologies is expected to reduce the potential complications associated with prosthesis applications.

Estimating the optimal entry point of the antegrade femoral nailing: Previous and novel morphometric measurements.

OBJECTIVE: This anatomical study aimed to investigate the possible relationships between the proximal femur parameters and verify the optimal entry point in line with the medullary canal. METHODS: Both in single image series and 3D-MPR views, 63 femur bones were evaluated. One-millimeter multidetector computed tomography scans were collected and assessed by OsiriX-Lite version 8 and Horos v3.3.5. Entry point locations, projected and true femoral neck-shaft, anteversion, and newly defined nail entrance angles were measured. RESULTS: The entry points of 16 femurs were placed at the tip of the greater trochanter, and the remaining 47 femurs were in the trochanteric fossa (i.e., piriformis fossa). Thirty-three of the entry points found in the trochanteric fossa were overlapped by the greater trochanter. When the parameters of the right and left sides were compared, it was found that; projected neck angle, nail entrance angle, and the differences between true neck angle and nail entrance angle were found significantly different. The relationship between nail entrance angle and entry point localization was assessed, and the probability of the entry point being at the tip of the greater trochanter is 63 times greater when the NEA is below 90. CONCLUSION: This study has demonstrated that the ideal entry point for straight nails, which is based on the anatomic axis of the femur, is found mainly at the trochanteric fossa, and the greater trochanter overlapped 70.21% of them. LEVEL OF EVIDENCE: Level IV, Diagnostic Study.

Tendon of Flexor Carpi Radialis in carpal tunnel: a radiologic and cadaveric study

Background/aim: Carpal tunnel is an important anatomical passage that carries the flexor tendons into the hand. As there is still no consensus about its contents among the anatomy textbooks, the main purpose of this study was to identify the relations of the flexor carpi radialis tendon in the carpal tunnel. Materials and methods: This retrospective study was completed in April 2018 at authors' university's hospital. Seventy-four female and 44 male patients' wrists without any pathology were examined by using magnetic resonance images. The series of axial sections where the pisiform exist were evaluated by using T1 sequence and the structures in the carpal tunnel were identified. Results: Results of this study showed that the tendon of the flexor carpi radialis was found above the flexor retinaculum within its own septal compartment in all patients. Conclusion: According to the results, tendon of flexor carpi radialis crosses the wrist region superficial to the carpal tunnel. Thus, tendon of flexor carpi radialis doesn't have any effect on the carpal tunnel syndrome. Further cadaveric studies would be useful for identifying the contents of the carpal tunnel and morphological organization of the wrist.