408 ABSTRACTS

still pictures from video images. Good slide quality and ease of use has led us to use a 380,000 pixel CCD TV camera and a video still recorder to record images on floppy disks.

Human vision calls for better picture quality in still pictures than in moving ones. In film cameras this quality depends on specifications of the film. In the magnetic recording of video, differences in the signal transferring and recording patterns on the tracks lead to differences in picture quality, circuit size, and difficulty of use. Whereas VHS, BETA, S-VHS and 8 mm videos employ amplitude modu- lation, the still video floppy system uses frequency modulation, leading to less color deviation.

Hardcopy apparatus, double scan CRT, and NTSC CRT were compared for the quality of slides they yielded. IIS results showed that hardcopy ap- paratus was best with double scan CRT and NTSC CRT following, but all proved to be significantly poorer than direct photography. When using small 1.5 or 2.7 mm arthroscopes, however, direct pho- tography may not always be best due to lighting and hand movement; in any case we believe that our system is adequate for the recording of arthroscopic exams and surgery, slides for conferences, or pic- tures for medical journals.

For the future we believe it necessary to de- velop a system in which the RGB output of the Video camera could be utilized to take in high qual- ity images directly as digital signals and use these recordings for graphic analysis by computer to pro- vide new information.

Arthroscopic Findings of Meniscal Suture of Dogs. An Experimental Study. Hitoshi Shimojyo and Toru Fukubayashi.

An experimental study of medial meniscal suture in mature dogs was undertaken and arthroscopic findings reviewed 1-12 weeks postoperatively.

One or 2 weeks postoperatively, suture sites were covered with hematoma and a hyperemic sy- novial fringe.

After 4 weeks, the hyperemic synovial fringe decreased and suture sites were observed to be al- most completely covered with fibrous tissue.

Arthroscopic and macroscopic findings were almost identical, but a few differences existed in some cases.

The Treatment of Osteochondrltis Dissecans of the Knee. Yoshinobu Watanabe, Fuho Suzu, Fumiharu

Arthroscopy, Vol. 7, No. 4, 1991

Yamashita, Hideyuki Tsuneoka, Yasusuke Hira- sawa, Kisaburo Sakakida, and Tomoyuki Kan.

We reviewed 14 patients (16 involved knees) with osteochondritis dissecans treated surgically over the past 8 years at the Hospital of Kyoto Prefectural University of Medicine.

Various surgical procedures were performed including removal of loose bodies, drilling the cra- ter, and different forms of fixing the detached car- tilage and grafting. Indications for surgical interven- tion depended on skeletal age of the patient, and size and location of the lesion.

Arthroscopic examinations were performed postoperatively. All internally fixed fragments (three cases) were covered with cartilage, but par- tially degenerative changes were observed at the articular surface. The drilled crater was occupied with fibrous tissue (two cases). Transplanted auto- genie osteochondral fragments in two patients ap- peared identical to normal cartilage when observed macroscopically and showed no signs of histologic degeneration.

All patients were asymptomatic at short-term follow-up study (from 1 to 8 years).

Arthroscopic Study of Coxarthrosi+Changes of Ar- titular Cartilage in Young Patients. Hirofumi Ohgiya, Yoshikatsu Kuroki, Susumu Saito, Shu Obara, Junji Hayashi, and Ken Yamazaki. Yoko- hama, Japan.

We reviewed arthroscopic findings of articular cartilage in young hip joints. Arthroscopy was per- formed on 46 hips in 39 cases between 11 and 29 years old. There was a correlation between stage of coxarthrosis and arthroscopic findings of acetabular cartilage. There was also a correlation between a past history of c.d.h. and arthroscopic findings of articular cartilage. There were many pathological findings in cases with capital deformity on x-ray examination compared with cases without capital deformity. In cases that demonstrate a narrowing of joint space on x-ray, normal capital cartilage arthro- scopic findings were observed, however normal ar- throscopic findings of acetabular cartilage were not. Considering these arthroscopic findings, joint space narrowing occurs mainly correlating to abnormal changes of acetabular cartilage.

Arthroscopic Examination of Osteochondral Lesions of the Talus. Masahiro Chiba, Hideki Takeuchi, and Nozomu Zmai.