Pronated Grip View With Wrist Deviation: A Pilot Study on the Effect on Ulnocarpal Relationships

Background We hypothesize that different positions of the wrist in the coronal plane makes the carpus susceptible to ulnar impaction. Methods We prospectively enrolled 10 adult volunteers and obtained fluoroscopic images of each wrist in 12 different positions using a standardized protocol. Distances from the ulna to the lunate (UL) and ulna to the triquetrum (UT) were digitally measured as was the portion of the lunate surface area that was uncovered (LUR) with wrist deviation. Results A wrist position of Pronation, Neutral Deviation, and Grip (P-ND-G) significantly shortened the ulnocarpal distance when compared to a position of Neutral Rotation, Neutral Deviation, and No Grip (NR-ND-NG). Radial deviation during pronation and gripping (Pronated, Radial Deviation, Gripping [P-RD-G]) resulted in the lowest mean UL distance (1.2 mm). UT distance was minimized by a position of ulnar deviation during a pronated grip (Pronated, Ulnar Deviation, Gripping [P-UD-G]) (3.1 mm). The lunate becomes more uncovered with radial deviation. Conclusion Radial deviation minimizes the UL distance while ulnar deviation minimizes the UT distance during a wrist position of pronation and gripping. Further, there is more proximal lunate surface area uncoverage during all positions of radial deviation compared to ulnar deviation.

The Pelves of Sunghir 1, 2, and 3

The pelvis forms the interface between the trunk and the lower limb, as well as supporting the pelvic viscera, and as such its size and morphology reflect a diversity of biological pressures. Aspects of the Sunghir pelvic remains relating to the assessment of sex (pubic morphology, greater sciatic notch shape) and age (auricular surface, epiphyses) are presented in chapter 6, and the features of the sacrum (and coccyx) that are more strictly axial are discussed in chapter 10. The discussion here is concerned with the overall configurations of the Sunghir pelvic remains and more detailed aspects related to function. Given the male sex of Sunghir 1 and the prepubescent ages of Sunghir 2 and 3, reproductive issues beyond those related to sex assessment are not relevant to these remains. Unfortunately, the pelvis for which comparative data and biomechanical models of function exist, that of the adult male Sunghir 1, is the least complete, sufficiently so as to prevent the articulation of the elements. In contrast, the two immature pelves are quite complete, despite problems with reassembly given their immature status. Yet assessing their proportions is inhibited by issues of growth and development. The pelvis of Sunghir 1, as with most of its trunk (chapter 10), suffered extensively from vertical compres­sion in situ. The pubic bones are absent, and the ilia and ischia sustained considerable damage, much of which has been restored in wax. For example, the left acetabular rim is largely intact, but the lunate surface and acetabular notch are blended together with wax, obscuring details. The sacrum retains neither of its alae intact to the auricular surface. The Sunghir 2 and 3 pelves, in contrast, are largely present, with varying degrees of edge damage and loss of the thinner cortical bone, especially within the iliac fossae of Sunghir 3. However, both pelves retain their more cranial sacra, at least one intact sacroiliac articulation, and variable portions of the ischia and pubic bones. The primary difficulties in assessing the Sunghir 2 and 3 pelves derive from their immature status.

Prosthetic Modeling of the Femoral Head Based on Reverse Method

In this paper, a new method for reconstructing the model of the necrotic femoral head is presented. It can reconstruct the optimal femoral head prosthesis model utilizing the reverse technology. This new method not only affords a theoretical model for the accurate operation position fixing in orthopaedic clinic, but also provides an innovative practical means for the individualized manufacturing of artificial femoral head prosthesis.The femoral head is regarded as a sphere. Then, the femoral head's configuration is reconstructed by means of fitting using the data points on the unspoiled acetabulum lunate surface. A spatial dynamic analysis is implemented, it is proved that the sphere fitting model can well satisfy the spatial motion relation between the femoral head and the acetabulum. The experiment results show that this method can well reconstruct the femoral head model of the target patient.

Altered Patterns of Subchondral Bone Mineralization in Kienböck’s Disease

The pattern of subchondral bone density, which is supposed to reflect the long-term distribution of stress, was investigated in both wrist joints of nine healthy young subjects and seven patients suffering from Kienböck’s disease by means of CT osteoabsorptiometry. Two density maxima were found on the distal articular surface of the radius in the healthy subjects, corresponding to the position of the scaphoid and the lunate. Our relative quantitative results showed three different physiological types of stress indicated by the predominantly monocentric density maxima either on the scaphoid or the lunate surface of the radius and the symmetrical distribution of the mineralization. In Kienböck’s disease no type of mineralization predominated. In the progressive stages the lunate density maximum was absent. The overall mineralization was generally less than in controls. Changes in the pattern of mineralization were also found on the contralateral side.