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4.9mm Direct View Arthroscope (Watanabe “Type No. 21”)

Health Sciences · Robert W. Jackson Arthroscopy

A metal optical instrument (arthroscope) consisting of several components.

The arthroscope has a black coloured eyepiece with a knurled edge. At the opposite end, a cylindrical stem leads to a forward-looking lens.

The arthroscope is inserted into a bulb carrier. The bulb carrier clamps onto a narrow rod protruding from the eyepiece of the microscope with a knurled knob. There is an electrical port for connecting the bulb carrier to an external power supply. There is a bulb fitted into the socket at the tip of the bulb carrier.

The arthroscope and bulb carrier are then inserted into a sheath. A rotating collar on the sheath locks the two elements into place. This sheath has a valve for attaching an irrigation system.

Accession Number: 2021.JAC.94

Alternative Name:

Primary Materials: Stainless Steel, Glass


Engraved or moulded in white lettering around the perimeter of the arthroscope eyepiece: “SHINKO KOKI 4552”

Dimensions (cm): Height = 5, Width = 5, Length = 16.5.


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.


This example is in excellent cosmetic condition and appears to be intact.

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.

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.

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