Kendrick E. Lee

Tuberculosis presenting as carpal tunnel syndrome

A 44-year-old man presented with typical symptoms, signs, and laboratory findings of carpal tunnel syndrome. Mycobacterium tuberculosis was cultured from the flexor tenosynovium excised at surgery. Tuberculosis should be considered in the differential diagnosis of carpal tunnel syndrome with unexplained chronic synovitis. The diagnosis may be missed unless a tissue specimen is analyzed specifically with acid-fast stain and culture. Therapy should include excision of involved synovium, early postoperative mobilization, and appropriate chemotherapy.

Proximal femoral epiphysiolysis in the neonate.

Seven neonates with eight proximal femoral epiphysiolyses were reviewed. Pain elicited by leg motion was the common diagnostic finding in all. Radiography showed lateralization of the shaft similar to congenital hip dysplasia. However, the acetabular index was normal in all but one child. Arthrography confirmed the diagnosis, showing a located proximal femoral epiphysis and a laterally displaced, externally rotated proximal metaphysis. Treatment usually consisted of traction followed by abduction splinting. The long-term results were excellent in six fractures. Growth complications included angular deformation (bowing) in one patient and coxa vara due to localized premature epiphysiodesis in one patient. Duplication of the lesion in stillborn cadavers showed that the fracture was usually a type 1 physeal injury traversing the entire physis beneath both the capital femur and the greater trochanter. The periosteal sleeve was intact posteriorly and still attached to the proximal physis. However, in two instances there was comminution (rather than crushing) of the epiphysis, physis, and metaphysis medially, which might explain the residual varus deformation and premature growth arrest seen infrequently as complications of this particular proximal femoral injury. An experimental animal model also duplicated these morphologic observations.

Shear fractures through the capital femoral physis of the skeletally immature rabbit.

Summary Shear fractures were created through the capital femoral physes of rabbits 2, 4, 6, 10, and 14 weeks of age. Biomechanically, the load to complete failure (i.e., fracture) increased with maturation. The load to failure increased with increasing area of the capital femoral physis. The shear stress increased with age and then began to plateau at 10 weeks of age. Histologically, the zone of failure involved the columnar zone in the specimens from rabbits 2–6 weeks old, progressed to the junction of the columnar and hypertrophic zones in the specimens from 10-week-old rabbits, and occurred within the zone of hypertrophy in the specimens from 14-week-old rabbits. Fractures progressed from a type I physeal fracture in the specimens from rabbits 4–6 weeks old to a type II physeal/metaphyseal fracture in the specimens from older animals, with the metaphyseal fragment increasing in size with increasing chondroosseous maturation of the specimen.

Histologic patterns of capital femoral growth plate fracture in the rabbit: the effect of shear direction.

Summary Growth plate fractures were produced in vitro in the rabbit capital femoral physis by applying shear loading parallel to the physeal complex in four different directions. Load-displacement curves were recorded and histologic sections were prepared from each specimen. Different histologic patterns were observed with different directions of shear loading. The histologic level within the growth plate through which the fracture propagated varied with each specimen and with the different directions of shear loading. The “classical” pattern of failure through the hypertropic cellular zone of the physis was not uniformly seen. The mechanical patterns of failure also varied with the direction of shear loading. The shear strength of the physeal complex was significantly greater with anterior to posterior loading than with posterior to anterior loading. The possible factors contributing to this mechanical anisotropy are discussed, and the literature on related studies is reviewed.

Infantile cortical hyperostosis with intramedullary lesions.

A case report of an infant with the clinical, radiological, and histological presentations of infantile cortical hyperostosis is presented. Besides the classically described subperiosteal thickening, the present patient radiographically also had well-circumscribed intramedullary lytic lesions in both proximal tibial metaphyses, which subsequently disappeared in 3 months. These lesions have not been previously described in the literature. Resolution of these lesions suggests they may be part of the radiological picture of infantile cortical hyperostosis and probably may be managed by observation.