Menu Close

Teaching attachment for Watanabe “Type No. 21” Arthroscope

Health Sciences · Robert W. Jackson Arthroscopy

A metal optical instrument consisting principally of a locking mechanism for attachment to the eyepiece of a Watanabe “Type No. 21” Arthroscope, as well as two eyepieces located at right angles to each other. The eyepieces can rotate freely relative to the locking mechanism.

Accession Number: 2021.JAC.98

Alternative Name:

Primary Materials: Stainless Steel, Glass


Stamped or engraved near the locking mechanism: “SHINKO”

Dimensions (cm):

Height = 15.5, Width = 5.5, Length = 14.5


An arthroscope is an optical instrument for viewing the interior of a joint during a surgical operation. Its development made possible minimally invasive surgery for many knee operations. It significantly improved diagnoses and healing times for many knee conditions. Specialized arthroscopes may also be used on smaller joints.

The teaching attachment permits a second view to directly observe the operation through the instrument. Such teaching attachments became obsolete when video cameras were first attached to the arthroscope eyepiece.

Note that Robert Jackson likely played a role in developing this teaching attachment. (See “Historical Notes” field below.)


This artifact is in good cosmetic condition. Both of the stems leading to the two eyepieces have small but noticeable scratches.

Associated Instruments:

Manufacturer: Shinko Optical Co., Tokyo, Japan.

Date of Manufacture: c. 1960s


The Robert W. Jackson Arthroscopy Collection was acquired by the University of Toronto from Dr. Jackson’s family on November 12th, 2020.

Additional Information and References:

DeMaio, Marlene. “Giants of Orthopaedic Surgery: Masaki Watanabe MD.” Clinical Orthopaedics and Related Research 471, no. 8 (August 2013): 2443–48.

Robert W. Jackson (corresponding author), William Clifford Roberts, MD “Robert Wilson Jackson, OC, MD, FRCS, FRCSC, FRCS(Ed): a conversation with the editor.” Baylor University Medical Center Proceedings. 2002 Apr; 15(2): 171–184. (Online version archived November 7, 2022)

The “History of the IAA” page of the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) provides a detailed account of the early development of the field of arthroscopy. (archived October 24, 2022).

Historical Notes:

The first arthroscopic surgery was performed by Dr. Kenji Takagi of Tokyo in 1918 using a commercial cytoscope (the Charriere No. 22). In 1931, Takagi produced the first in a series of prototype arthroscopes. (See DeMaio 2013 for a detailed account). The first production arthroscope, the “Type No. 21,” was developed by a student of Takagi, Masaki Watanabe in 1959. Manufactured by Shinko Optical Co. of Tokyo Japan, it became the first production arthroscope.

Watanabe scopes were used by Dr. Robert R. Jackson at the Tokyo Teishin Hospital where he studied under Dr. Watanabe in 1964-65. Jackson was involved in introducing the arthroscope to his North American colleagues. He also helped to establish a North American distributor for the arthroscopes. This was Professional Orthopaedic Supplies, Ltd, located in Mississauga, Ontario. Along with M. Watanabe, S. Takeda, and H. Ikeuchi, he developed an English translation of the related trade literature.

Note that Robert Jackson likely had a role in developing the teaching attachment. In the interview published in Jackson and Roberts 2002, Jackson notes: “… When I arrived, [Masaki Watanable] had only one viewing apparatus. Together, we developed sidebars (beam splitters), so both of us could look into the joint simultaneously. A little later we devised flexible teaching attachments so the surgeon could have 70% of the light, and those trainees viewing through a fiber optic cable could have 30% of the light. It was a very crude apparatus at that time.”

The Type 21 arthroscope encompassed a set of apparatus that was usually sold as a boxed set. This set included two arthroscope “telescopes,” one forward looking, the other providing a side view. Both had an electrical connection to supply current from a transformer unit to a tiny halogen bulb. The forward-looking telescope used a separate “bulb carrier” fitted between the scope and its corresponding sheath. On the side-looking unit, the bulb was integrated into the telescope. Both scopes had a corresponding sheath that facilitated insertion into the incision. The sheaths had stopcocks providing entry points for a saline irrigation system that was used to distend the joint during operation.

The arthroscope set included two trocar needles, used to create the keyhole incisions, as well as a blunt obturator and a pair of narrow forceps with biopsy punch tips. It also included consumables such as extra rubber seals and light bulbs. A number of accessories were also available, including a teaching adapter that added a second eyepiece, a camera adapter and an adapted film camera, and a formalin gas chamber for disinfecting the instrument, and other components.

This early instrument presented several challenges. Its integrated incandescent bulb gave off heat and could break, requiring careful removal of the glass shards. The telescopes had to be disinfected using formalin gas; accidental autoclaving would damage the instrument, which could not be repaired in North America.

Watanabe developed at least two further arthroscopes. The Type 22, introduced in 1967, replaced the incandescent bulb with fiber optic illumination. The Type 25, introduced in 1970, was a narrow 2mm arthroscope that was developed for the arthroscopy of small joints. Neither example is represented in this collection. However, the Type 25 was developed into the “Needlescope” for sale in North America. There are two examples in this collection. 

  • Donated to UTSIC