PubMed · 10691085
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
C G Macias. 2000. Radial head subluxation.. https://doi.org/10.1111/j.1553-2712.2000.tb00533.x
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
According to the equilibrium point theory, the control of posture and movement involves the setting of equilibrium joint positions (EP) and the independent modulation of stiffness. One model of EP control, the alpha-model, posits that stable EPs and stiffness are set open-loop, i.e. without the aid of feedback. The purpose of the present study was to explore for the elbow joint the range over which stable EPs can be set open-loop and to investigate the effect of co-contraction on intrinsic low-frequency elbow joint stiffness (K (ilf)). For this purpose, a model of the upper and lower arm was constructed, equipped with Hill-type muscles. At a constant neural input, the isometric force of the contractile element of the muscles depended on both the myofilamentary overlap and the effect of sarcomere length on the sensitivity of myofilaments to [Ca2+] (LDCS). The musculoskeletal model, for which the parameters were chosen carefully on the basis of physiological literature, captured the salient isometric properties of the muscles spanning the elbow joint. It was found that stable open-loop EPs could be achieved over the whole range of motion of the elbow joint and that K (ilf), which ranged from 18 to 42 N m.rad(-1), could be independently controlled. In the model, LDCS contributed substantially to K (ilf) (up to 25 N m.rad(-1)) and caused K (ilf) to peak at a sub-maximal level of co-contraction.
Explore the source record for details and available documents.
Bipolar dislocation injury of the forearm is rarely documented. It is a combined forearm injury with trauma on the elbow side and on the side of the wrist joint. We describe two different cases of this complex dislocation. The first patient suffered from a Monteggia-like dislocation fracture with transscaphoid dislocation of the wrist. The second person had an acute longitudinal radioulnar membrane dissociation after elbow dislocation with an additional scapholunate tendon rupture. The difficult management of these injuries is illustrated by these cases.