This study was performed in accordance with the provisions of the Declaration of Helsinki 1995 (as revised in 2013). The unilateral wrists and ankles of 16 late-term fetuses of gestational age 30–40 weeks and crown-rump length 255–325 mm had been cut into semiserial sections of 200–300 micron intervals and stained with hematoxylin and eosin, as described [5 (link), 8 (link)]. The sectional plane was sagittal in four wrists and ten ankles, frontal in six wrists and horizontal in six wrists and six ankles.
All fetuses were part of the collection of the Department of Anatomy, Akita University and had been donated by their families to the Department in 1975–1985 and preserved in 10% w/w neutral formalin solution for more than 30 years. Data on these specimens included the date of donation and the number of gestational weeks, but did not include the name of the family, obstetrician or hospital or the reason for abortion. The use of these specimens for research was approved by the Akita University Ethics Committee (No. 1428). Dr. Hiroshi Abe, Emeritus Professor at Akita University, kindly permitted us to use these materials. Before routine procedures for embedding in paraffin, the fetal limb specimens were decalcified by incubation at room temperature in Plank-Rychlo solution (AlCl2/6H2O, 7.0 w/v%; HCl, 3.6 w/v%; HCOOH, 4.6 w/v%) for 3–7 days. Most photographs for histology were taken with a Nikon Eclipse 80 (Nikon, Tokyo, Japan), whereas photographs at ultra-low magnification (objective lens less than ×1) were obtained using a high-grade flat scanner with translucent illumination (Epson scanner GTX970; Epson, Tokyo, Japan).
Unilateral wrists and ankles were dissected from the cadavers of 15 elderly individuals, mean age 82 years (range, 75–97 years) at time of death. All cadavers had been donated to Tokyo Dental College for research and education on human anatomy, and had been fixed by arterial perfusion of 10% v/v formalin solution and stored in 50% v/v ethanol solution for more than 3 months. The use of cadavers for research was approved by the ethics committee of Tokyo Dental College (No. 932). The cause of death in all individuals was ischemic disease of the heart or brain. For dissection, the carpal tunnel and extensor tendon sheathes at the wrist was opened and the retinaculum at the ankle was removed to expose long tendons of the flexor and fibular muscles. After labeling the joint surfaces, photographs were taken of the wrist and ankle tendons. Deep flexor tendons were visualized after cutting and retraction of the superficial tendons.
All fetuses were part of the collection of the Department of Anatomy, Akita University and had been donated by their families to the Department in 1975–1985 and preserved in 10% w/w neutral formalin solution for more than 30 years. Data on these specimens included the date of donation and the number of gestational weeks, but did not include the name of the family, obstetrician or hospital or the reason for abortion. The use of these specimens for research was approved by the Akita University Ethics Committee (No. 1428). Dr. Hiroshi Abe, Emeritus Professor at Akita University, kindly permitted us to use these materials. Before routine procedures for embedding in paraffin, the fetal limb specimens were decalcified by incubation at room temperature in Plank-Rychlo solution (AlCl2/6H2O, 7.0 w/v%; HCl, 3.6 w/v%; HCOOH, 4.6 w/v%) for 3–7 days. Most photographs for histology were taken with a Nikon Eclipse 80 (Nikon, Tokyo, Japan), whereas photographs at ultra-low magnification (objective lens less than ×1) were obtained using a high-grade flat scanner with translucent illumination (Epson scanner GTX970; Epson, Tokyo, Japan).
Unilateral wrists and ankles were dissected from the cadavers of 15 elderly individuals, mean age 82 years (range, 75–97 years) at time of death. All cadavers had been donated to Tokyo Dental College for research and education on human anatomy, and had been fixed by arterial perfusion of 10% v/v formalin solution and stored in 50% v/v ethanol solution for more than 3 months. The use of cadavers for research was approved by the ethics committee of Tokyo Dental College (No. 932). The cause of death in all individuals was ischemic disease of the heart or brain. For dissection, the carpal tunnel and extensor tendon sheathes at the wrist was opened and the retinaculum at the ankle was removed to expose long tendons of the flexor and fibular muscles. After labeling the joint surfaces, photographs were taken of the wrist and ankle tendons. Deep flexor tendons were visualized after cutting and retraction of the superficial tendons.
