Shigeaki Wakita

Chemonucleolysis with calpain I in rabbits.

Calpain I is a calcium-dependent cysteine proteinase that has been recently shown to degrade proteoglycan in vitro. The authors injected calpain I, which was purified from human red blood cells, into the intervertebral discs of rabbits. Roentgenograms showed disc space narrowing 1 week after the injection. Histologically, proteoglycan of the nucleus pulposus and anulus fibrosus decreased and notochordal cells in the nucleus pulposus almost disappeared. Biochemical data of the nucleus pulposus showed that the amounts of smaller proteoglycans increased 1 and 4 weeks after the injection. Eight weeks after the injection, histologic and biochemical data showed recovery compared with the data 1 week after injection. These findings show that caipain I is as potent an enzyme as chondroitinase ABC and has milder chemonucleolytic action than chymopapain. Regarding its possible clinical application, autogenous calpain I as purified from the patients own red blood cells may have advantages over chymopapain and chondroitinase ABC in that it will prevent anaphylactic reaction.

Diagnosis by ultrasound of congenital dislocation of the hip joint.

Two hundred thirty-four hips of 117 babies from one day to 18 months of age were examined ultrasonographically for congenital dislocation of the hip joint. Ten hips in eight babies were dislocated or subluxated and there were 11 hip dysplasias in seven babies. In the normal hip, the adaptation between the acetabulum and the femoral head is well demonstrated, and there is no apparent interposition of the limbus between the acetabular roof and the cartilaginous head. In the dislocated hip, the protrusion of the acetabular rim is not so clear as that of the normal hip, and the limbus is seen to be interpositioned between the acetabular roof and the cartilaginous head. In severe cases, the acetabular rim is hidden under the shade of the femoral head. Ultrasonography is an effective method of determining the incidence of dislocation and of diagnosing hip subluxation as well as dysplasia and does not have the hazards of x-ray examination.