Gait biomechanics and the evolution of total joint replacement

The history and evolution of total knee and total hip replacement has been influenced substantially by the knowledge obtained from gait analysis studies. Many of the mechanical problems associated with these devices have been analyzed and evaluated in terms of the mechanics of walking. The magnitude and pattern of the forces at the hip and knee joints derived from gait analysis studies have provided valuable input into the design criteria of both total hip and total knee replacements. Information generated from the gait analysis of patients with total joint replacements has provided objective criteria for assessing functional recovery following this procedure. In addition to providing a basis for design evaluation, the key to the analysis of function following joint replacement is the ability to identify functional adaptations specific to design features. Gait analysis provides a unique opportunity to obtain objective information that cannot be obtained through other clinical means and provides a means for evaluating current designs and future design modifications.     

Paraneoplastic movement disorder in a patient with non-Hodgkin's lymphoma and CRMP-5 autoantibody.

The paraneoplastic autoantibody, collapsin response-mediator protein (CRMP)-5 immunoglobulin G (IgG), is specific for neuronal cytoplasmic CRMP-5, and is usually associated with small-cell lung carcinoma or thymoma. We report on details of a movement disorder that followed anti-B-cell therapy in a patient with lymphoma, and was accompanied by CRMP-5 IgG.     

The distribution of the tumour photosensitizers Zn(II)-phthalocyanine and Sn(IV)-etiopurpurin among rabbit plasma proteins.

Zn-phthalocyanine (ZnPc) and Sn-etiopurpurin (SnET2) incorporated in unilamellar liposomes or solubilized in a Cremophor-EL emulsion have been incubated in vitro with rabbit plasma or intravenously administered to rabbits. Ultracentrifugation and chromatographic analysis of the plasma showed that ZnPc and SnET2 are mainly released to lipoproteins; within the lipoprotein family, both dyes are preferentially bound by low-density (LDL) and high-density (HDL) lipoproteins. The amount of dye bound with these two lipoprotein classes was related to their relative concentration in the plasma; in most cases a larger amount of photosensitizer was bound to HDL as compared to LDL on a protein concentration basis.     

Deprivation of form vision suppresses diurnal cycling of retinal levels of leu-enkephalin

Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth.     

Malignant colonic polyps: is polypectomy adequate treatment?

The management of patients with endoscopically removed malignant intestinal polyps is controversial. The risk of residual disease should be assessed against the risk of a surgical operation. The authors report 35 cases of malignant polyps (5.5% of 641 colonoscopically removed adenomas). Sixteen patients had carcinoma in situ and received no further treatment and 19 had invasive carcinoma (sessile in 6, pedunculated in 13). Of these 19, 7 did not undergo surgery--because of old age in 2, minimal invasion in 3, a low rectal location in 1 and refusal in 1. Twelve patients (3 with sessile, 9 with pedunculated polyps) underwent a surgical resection, and residual disease was present in 3 (25%), 1 with positive nodes. Reported criteria of increased risk of residual disease--cancer in lymphatics or veins, incomplete excision, tumour at resection margin, sessile and villous tumours--were present in nine. All three patients with residual disease had microscopically involved margins of resection. The authors believe that the increased risk of recurrence justifies the risk associated with subsequent surgical resection unless the patient is otherwise a poor operative risk.