Plantar Plate

So-called turf toe describes a sprain of the first metatarsophalangeal joint in which there is partial or complete disruption of the plantar plate, presenting with persistent hyperextension of the proximal phalanx. Similar to the volar plate in the hand, the... 

Fig. 17.46a,b. Turf toe. Schematic drawings illustrate the pathomechanism of this condition, a During normal dorsiflexion of the first metatarsophalangeal joint, the plantar plate (asterisk) is subjected to stretching forces (double-headed arrow) as a result of tension applied to the plantar capsule, b With excessive extension (curved white arrows), the metatarsal neck (MH) impinges on the base of the proximal phalanx (Ph) and transmits excessive tension (double-headed arrow) to the plate causing its disruption. 

Blitz NM, Christensen JC, Ford LA (2002) Plantar plate ruptures of the second metatarsophalangeal joint. J Foot Ankle Surg 41 138-139... 

Blitz NM, Ford LA, Christensen JC (2004) Plantar plate repair of the second metatarsophalangeal joint technique and tips. J Foot Ankle Surg 43 266-270 Bodner G, Stockl B, Fierlinger A et al (2005) Sonographic findings in stress fractures of the lower limb preliminary findings. Eur Radiol 15 356-359... 

Yao L, Cracchiolo A, Farahani K et al (1996) Magnetic resonance imaging of plantar plate rupture. Foot Ankle Int... 

The dynamic distributed load that corresponds to the vertical ground reaction force can be evaluated with the use of a flat, two-dimensional array of small piezoresistive sensors. OveraU resolution of the transducer is dictated by the size of the individual sensor ceU. Sensor arrays configured as shoe insole inserts or flat plates offer the clinical user two measurement alternatives. Although the currently available technology does afford the clinical practitioner better insight into the quahtative force distribution patterns across the plantar surface of the foot, its quantitative capabiKty is limited because of the challenge of caKbration and signal drift (e.g., sensor creep). 

Nociception pain perception can be measured in rodents by a variety of procedures whereby aversive stimulation is applied externally either by heat or electrical stimulation to the tail or paws (tail flick, hot plate, plantar test) or internally by injection into the peritoneum of chemicals (acetic acid, phenylbenzoquinone). Inflammation pain can also be induced by injecting chemicals (carrageenan, formalin) into the paws. More complex approaches induce neuropathic pain by surgical lesions, usually to the sciatic or spinal nerve. For safety pharmacology purposes, usually only the simpler procedures are used. For example, with the hot plate test [18] the animal is placed onto a heated metal plate (54°C) within a vertical cylinder, and the latency to licking its front paws is measured over a short period. 

Zellmer, S., and Lasch, J. (1997). Individual variation of human plantar stratum comeum lipids, determined by automated multiple development of high performance thin layer chromatography plates. J. Chromatogr., B Biomed. Appl. 691 321-329. Zieloff, K. (1995). Automation in thin layer chromatography and good laboratory practice (GLP). Oesterr. Chem. Z. 96 120-122. 

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