Outcome of carpal tunnel release--correlation with wrist and wrist-palm anthropomorphic measurements.

Wrist and wrist-palm measurements have been associated with the diagnosis of carpal tunnel syndrome. We found no reported study about how this correlation affects the outcome after surgery. We investigated the role of the measurements in predicting outcome after open carpal tunnel release. A total of 131 patients (88 female, 43 male) responded to our postal questionnaire using the Boston Carpal Tunnel assessment (65% response rate) at a minimum of 9 months post-operatively. Symptom and functional scores showed a strong correlation. There was no statistical difference in the outcome between wrist ratio (≥0.7 vs <0.7), wrist-palm ratio (≥0.41 vs <0.41) and gender, but a better functional score was very weakly correlated with a higher wrist ratio. A very large study would be needed to show any statistical correlation between both measurement and outcome.

An unusual cause of locking after total knee replacement.

Locking after total knee replacement is uncommon and is generally caused by the formation of fibrous tissue around the patella. We report an unusual cause of locking resulting from intermittent occlusion of the popliteal artery, which was tethered to cement at the posterior aspect of the tibial component.

The Essex-Lopresti lesion: a variant with a bony distal radioulnar joint injury.

The Essex-Lopresti lesion is an unusual injury, consisting of a radial head or neck fracture, distal radioulnar joint (DRUJ) injury and interosseous membrane rupture. To date, all reported Essex-Lopresti lesions have consisted of soft tissue injuries at the DRUJ. We present a case of an Essex-Lopresti lesion with a bony variant, in which the DRUJ injury consisted of an ulnar head fracture associated with radial head fracture and acute proximal migration of the radius. The management involved plating of the ulnar head fracture and titanium replacement of the radial head.

A review of wound healing following Maquet osteotomy.

Maquet osteotomy can be associated with an unacceptably high incidence of wound complications that may be as high as 37%. A consecutive series of 42 Maquet osteotomies has been performed between 1990 and 2002 by a single surgeon without a single wound problem or infection and this series is the subject of this report. The use of an anterolateral incision reduces the damage to the major lymphatics minimising the risk of wound oedema. Identification and preservation of the feeding musculocutaneous vessels on the lateral and medial sides facilitates extensive but safe mobilisation of the skin flaps permitting an easy closure over a substantially elevated tibial tubercle. The use of an anterolateral incision with knowledge of the blood supply of the leg has eliminated the wound complications associated with the standard anteromedial incision reported previously in the literature. This approach, preserving the blood supply and lymphatic drainage, avoids skin necrosis and wound dehiscence, obviates any requirement for plastic surgical procedures such as releasing incisions or skin grafts and minimises the risk of infection and osteomyelitis.

Phase-conjugate reflection from a temporal dielectric boundary.

Electromagnetic theory predicts the generation of a backward-traveling wave when the velocity of a forward-propagating electromagnetic field inside a dielectric medium varies as a function of time. The backward wave is a phase-conjugate replica of the incident field and possesses some interesting properties. The mechanism giving rise to the phase-conjugate wave is a temporal analog of the Fresnel reflection that occurs when an electromagnetic field encounters a spatial dielectric boundary. We derive the dependence of the phase-conjugate reflectivity on the rate of change of the dielectric constant and show the difficulty of observing this type of phase-conjugate wave.

Structural studies on HCN oligomers.

NMR spectral studies on the HCN oligomers suggest the presence of carboxamide and urea groupings. The release of CO2, H2O, HCN, CH3CN, HCONH2 and pyridine on pyrolysis is consistent with the presence of these groupings as well as carboxylic acid groups. No basic primary amine groupings could be detected with fluorescamine. Hydrazinolysis of the HCN oligomers releases 10% of the amino acids normally released by acid hydrolysis. The oligomers give a positive biuret test but this is not due to the presence of peptide bonds. There is no conclusive evidence for the presence of peptide bonds in the HCN oligomers. No diglycine was detected on partial hydrolysis of the HCN oligomers at pH 8.5 suggesting that HCN oligomers were not a source of prebiotic peptides.

Spatial convolution and correlation of optical fields via degenerate four-wave mixing.

A nonlinear optical technique is described that performs, essentially instantaneously, the functions of spatial correlation and convolution of spatially encoded waves. These real-time operations are accomplished by mixing spatially dependent optical fields in the Fourier-transform plane of a lens system. The use of a degenerate four-wave mixing scheme eliminates (in the Fresnel approximation) phase-matching restrictions and (optical) frequency-scaling factors. Spatial bandwidth-gain considerations and numerical examples, as well as applications to nonlinear microscopy, are presented.