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Dive into the research topics where Jun-ichi Ishikawa is active.

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Journal of Hand Surgery (European Volume) | 1996

Clinical results of treatment of triangular fibrocartilage complex tears by arthroscopic debridement

Akio Minami; Jun-ichi Ishikawa; Naoki Suenaga; Toshihiko Kasashima

In order to determine indications for arthroscopic debridement and the management of triangular fibrocartilage complex (TFCC) tears, we reviewed 16 wrists retrospectively. The mean patient age was 30 years, with a range of 20 to 53 years. The follow-up period averaged 35 months. Two groups were identified: post-traumatic tears (n = 11) and degenerative tears (n = 5). The results of arthroscopic debridement were compared and analyzed based on the preoperative and postoperative evaluation of pain, range of motion, grip strength, return to work, patient acceptance, and complications. Failures were further evaluated to determine identifiable lesions or anatomic defects associated with poor results. Patients with positive ulnar variance and lunotriquentral interosseous ligament tears had a poor clinical outcome. Good results correlated with grip strength; all patients with post-traumatic TFCC tears had excellent results, while those with degenerative TFCC tears did poorly.


Journal of Hand Surgery (European Volume) | 1995

The Sauvé-Kapandji procedure for osteoarthritis of the distal radioulnar joint

Akio Minami; Katsunori Suzuki; Naoki Suenaga; Jun-ichi Ishikawa

The Sauvé-Kapandji procedure has been performed in 15 patients with primary and secondary osteoarthritis of the distal radioulnar joint. The average age of the patients was 45 years (range, 31-63 years). There were 12 men and 3 women. The follow-up period averaged 2 years and 11 months. Postoperative pain relief was good in all wrists. The preoperative range of motion of the wrist joint averaged 50 degrees extension and 44 degrees flexion. Forearm motion averaged 66 degrees pronation and 64 degrees supination. Postoperatively, the range of motion improved to 55 degrees extension and 51 degrees flexion at the wrist and forearm motion improved to 78 degrees pronation and 82 degrees supination. Although all wrists also showed an increased grip strength and improved range of motion over preoperative values, these did not have statistical significance. Postoperative x-ray evaluation showed an unstable proximal stump and radioulnar convergence in 12 wrists. Our clinical and x-ray film findings suggest that the Sauvé-Kapandji procedure is a satisfactory procedure for patients with osteoarthritis of the distal radioulnar joint.


Hand Surgery | 2005

Treatments of osteoarthritis of the distal radioulnar joint: long-term results of three procedures.

Akio Minami; Norimasa Iwasaki; Jun-ichi Ishikawa; Naoki Suenaga; Kazunori Yasuda; Hiroyuki Kato

Sixty-one wrists in 61 patients with osteoarthritis of the distal radioulnar joint treated by three consecutive procedures (20 Darrach, 25 Sauvé-Kapandji and 16 hemiresection-interposition arthroplastic procedures) were retrospectively evaluated. We preferred to perform Darrachs procedure in even the early stages of osteoarthritis of the distal radioulnar joint prior to introduction of Sauvé-Kapandji and hemirestion-interposition arthroplastic procedures. Subsequently the hemirestion-interposition arthroplasty was indicated when the triangular fibrocartilage cartilage was intact or could be reconstructed and the Sauvé-Kapandji when the triangular fibrocartilage complex could not be reconstructed or there was positive ulnar variance of more than 5 mm even though the triangular fibrocartilage complex was functional. Patients age at operation averaged 59.8 years. There were 36 men and 25 women. There were 38 primary and 23 secondary osteoarthritis cases. Post-operative pain, range of motion, grip strength, return to work status; and radiographic results were evaluated. At the five- to 14-year (average, ten years) follow-up evaluation, relief of pain from Darrach procedure was inferior to the Sauvé-Kapandji procedure and hemiresection-interposition arthroplasty although this was not statistically significant. After both the Sauvé-Kapandji procedure and hemiresection-inteposition arthroplasty, post-operative improvements in flexion and extension of the wrist had statistical significance. Post-operative improvements in pronation and supination of the forearm showed statistical significances after all procedures. Improvements of post-operative grip strength and return to an original job in the Sauvé-Kapandji procedure and hemiresection-interposition arthroplasty were statistically superior to those with a Darrachs procedure. There were many post-operative complications following the Darrachs procedure. Darrachs procedure is better indicated for severe osteoarthritic changes of the distal radioulnar joint in elderly patients. We believe the operative indications between the Sauvé-Kapandji procedure and hemiresection-interposition arthroplasty are best determined prior to surgery by the existence and status of the triangular fibrocartilage complex and the amount of the positive ulnar variance.


Journal of Biomechanics | 1997

Feasibility of using a magnetic tracking device for measuring carpal kinematics

Jun-ichi Ishikawa; Glen L. Niebur; Shigeharu Uchiyama; Ronald L. Linscheid; Akio Minami; Kiyoshi Kaneda; Kai Nan An

While several different methods have been used to measure carpal kinematics, biplanar radiography is generally considered to be the most accurate and popular one. However, biplanar radiography is tedious and so only pseudo-dynamic kinematics can be measured. Recently, magnetic tracking system has been developed for the measurement of joint kinematics which is versatile and easy to use and so the possibility of measuring motions dynamically. In this study, the capability of a magnetic tracking device to accurately measure carpal kinematics was investigated by comparing it with biplanar radiography. The kinematics of the third metacarpal, scaphoid, and lunate in five fresh cadaveric specimens were measured using both methods as the wrists were placed in eight positions. The finite screw rotation of each bone with respect to the distal radius during selecting the seven wrist motions was calculated for both measuring techniques and compared. In general, the kinematics for all three bones measured by using either magnetic tracking device or biplanar radiography was identical and showed no statistical difference. The averaged differences ranged from 0.0 to 2.0 degrees. These differences were due to the potential effect of the weight of the sensors and the interference of the attaching rod to the surrounding tissue. It is concluded that the application of the magnetic tracking device to carpal kinematics is warranted, if proper technical procedures as suggested are followed.


Journal of Bone and Joint Surgery, American Volume | 2007

Tumor Location Affects the Results of Simple Excision for Multiple Osteochondromas in the Forearm

Jun-ichi Ishikawa; Hiroyuki Kato; Fumio Fujioka; Norimasa Iwasaki; Naoki Suenaga; Akio Minami

BACKGROUND The effectiveness of excision of osteochondromas in controlling the progression of forearm and wrist deformity remains an issue of controversy. The purpose of this study was to analyze the effectiveness of tumor excision in the correction of forearm and wrist deformity due to multiple osteochondromas in children, with an interpretation of the results based on different patterns of deformity. METHODS Fourteen forearms in thirteen children with a follow-up of more than twenty-four months (average, fifty-three months) were included in the study. The forearms were divided into two groups on the basis of the location of the tumor and the pattern of deformity. In Group 1 (six forearms), the osteochondroma was only in the distal aspect of the ulna and caused compression of the radius. In Group 2 (eight forearms), tumors were in both the distal aspect of the ulna and the ulnar side of the distal part of the radius and were in contact with each other. Radial length, ulnar shortening, radial bowing, the radial articular angle, and carpal slip were measured as radiographic parameters. Ulnar shortening and radial bowing were expressed as a percentage of the radial length to make it possible to compare data between the individuals. Each parameter was evaluated before surgery and at the time of final follow-up. RESULTS In Group 1, the percentage of ulnar shortening and the percentage of radial bowing had improved at the time of final follow-up; however, in Group 2, both the radial articular angle and the percentage of radial bowing had deteriorated significantly after the tumor excision (p = 0.049 and p = 0.017, respectively), even though the percentage of ulnar shortening showed no change. CONCLUSIONS The effectiveness of simple excision of osteochondromas of the distal aspect of the forearm is influenced by the tumor location and is related to the pattern of the deformity. Simple tumor excision can correct the forearm deformity in patients with an isolated tumor of the distal part of the ulna. Conversely, in patients with tumors involving the distal part of the ulna and the ulnar side of the distal end of the radius, tumor excision alone is a less promising procedure for the correction of the deformity. LEVEL OF EVIDENCE Prognostic Level IV.


Hand Surgery | 2009

RADIOLUNATE FUSION WITH DISTRACTION USING CORTICOCANCELLOUS BONE GRAFT FOR MINIMIZING DECREASE OF WRIST MOTION IN RHEUMATOID WRISTS

Tatsuya Masuko; Norimasa Iwasaki; Jun-ichi Ishikawa; Hiroyuki Kato; Akio Minami

Radiolunate fusion is a limited carpal fusion procedure used for patients with rheumatoid arthritis. However, this procedure inevitably causes decreases in range of motion, especially wrist flexion. Linscheid and Dobyns described the possibility of minimizing the decrease in motion at the radiocarpal joint by slight distraction of the joint. We hypothesized for our modified procedure that a corticocancellous bone graft was inserted between the radius and the lunate with a small amount of over-correction could provide slight distraction of radioscaphoid joint and protect the joint from decreased range of motion after arthrodesis. Twelve wrists in ten patients with rheumatoid arthritis underwent radiolunate fusion. Mean age at operation was 53 years old and mean follow-up period was 5.7 years. Clinical evaluation and radiological assessment showed that decrease in range of motion was minimized compared with other procedures. Because our modified procedure can minimize decrease in motion, it is recommended.


Journal of Hand Surgery (European Volume) | 2006

Stabilization of the proximal ulnar stump in the Sauvé-Kapandji procedure by using the extensor carpi ulnaris tendon : Long-term follow-up studies

Akio Minami; Norimasa Iwasaki; Jun-ichi Ishikawa; Naoki Suenaga; Hiroyuki Kato


Journal of Hand Surgery (European Volume) | 2005

Influence of Distal Radioulnar Joint Subluxation on Restricted Forearm Rotation After Distal Radius Fracture

Jun-ichi Ishikawa; Norimasa Iwasaki; Akio Minami


International Orthopaedics | 1995

Hemiresection-interposition arthroplasty for osteoarthritis of the distal radioulnar joint

Akio Minami; Katsunori Suzuki; Naoki Suenaga; Jun-ichi Ishikawa


Journal of Orthopaedic Science | 2011

Non-vascularized bone graft with Herbert-type screw fixation for proximal pole scaphoid nonunion.

Hiroyuki Matsuki; Jun-ichi Ishikawa; Norimasa Iwasaki; Shigeharu Uchiyama; Akio Minami; Hiroyuki Kato

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