Biomedical subjects

I J Alexander

Publications and source records attributed to I J Alexander.

22 records · Page 2Linked to original sources

PubMed1987

Morton's neuroma: a review of recent concepts.

A number of new concepts in the pathology, diagnosis, and management of Morton's metatarsalgia have been presented in the recent literature. Probably as many questions as answers have been generated by these publications. The taut transverse metatarsal ligament appears to play a critical role compressing the interdigital nerve but the exact pathomechanics producing the neuroma and the role of the intermetatarsal bursa remain unclear. Electrodiagnostic techniques for this condition are in the early development stage and may be clinically applicable in the near future. Support for and recommendation against the preoperative injection of the intermetatarsal bursa and interdigital nerve area have been discussed. The necessity of interdigital neurectomy has been questioned but currently in North America, simple transverse metatarsal ligament division has not been widely utilized. Continued studies along these lines should improve our understanding of Morton's metatarsalgia, increase our diagnostic accuracy, and facilitate more effective management.

Bursa, Synovial↗

PubMed1987

Aggressive fibromatosis of the plantar aspect of the foot. A case report.

Distinguishing superficial plantar fibromatosis from deep fibromatosis of the plantar aspect of the foot is difficult both clinically and histologically. An illustrative case is presented. Clinical factors suggestive of aggressive fibromatosis include presentation at an age younger than 20 years, tumor dimension exceeding 3 cm (without prior surgical excision), and multicentric occurrence in the affected limb. On histological review, the absence of nodule formation favors the diagnosis of deep aggressive fibromatosis.

Adult↗

PubMed1984

Knee joint effusion and quadriceps reflex inhibition in man.

This study was designed to elucidate the role of effusion in producing the reflex inhibition, and subsequent atrophy, of quadriceps musculature following knee trauma. In particular, consideration was given to determining the extent, threshold and linearity of inhibition of the motoneuron pool induced by experimental introduction of small increments of 0.9% physiological saline (up to 60ml) into the joint space of the knee in ten healthy subjects. Inhibition of the quadriceps muscle motoneuron pool was indirectly assessed through recording Hoffmann (H) reflexes evoked from vastus medialis, lateralis and rectus femoris. All ten subjects showed a significant (p less than 0.05) reduction in H-reflex amplitude following the introduction of saline: vastus medialis reduced to 55.7 +/- 4.3% of its control 0ml value, rectus femoris to 69.1 +/- 6.1% and vastus lateralis to 65.3 +/- 4.0%. Post hoc analyses of the H-reflex amplitudes at each increment of simulated effusion revealed the threshold for reflex inhibition of the vastus medialis to be between 20 and 30ml of saline and for rectus femoris and vastus lateralis to be between 50 and 60ml. These procedures were repeated on eight subjects following an injection of the anesthetic lidocaine (1%) to the intra-articular space of their knee joints but there was no significant reduction in H-reflex amplitude. Linear relationships were found to adequately describe the relationships between the volume of effusion and intra-articular pressure; and volume of effusion and reduction in H-reflex amplitude.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Nerve supply of the human knee and its functional importance.

This investigation utilized gross dissections, histological preparations, and neurophysiologic experiments to gain an improved understanding of the innervation of the human knee. Anatomical illustrations represent the findings of dissections of 15 fresh amputation specimens. Neurohistologic preparations using silver staining techniques demonstrate the rich innervation of the soft tissues of the knee, and a variety of specialized receptors are identified. In 10 subjects with normal knees, and experimentally produced knee effusion of 60 cc was found to result in profound inhibition of reflexly evoked quadriceps contraction. Clinical implications of the anatomical and physiologic data are discussed.

Axons↗