Ichiro Okutsu

Endoscopic management of carpal tunnel syndrome.

This article describes a subcutaneous endoscopic operative procedure for carpal tunnel syndrome and analyzes its effectiveness using electrophysiological data. Subcutaneous transverse carpal ligament release under universal subcutaneous endoscope (USE) was performed using local anesthesia without pneumotourniquet in 54 hands of 45 patients since June 1986. The mean follow-up period was 13.8 months. Sensory disturbances began to subside immediately after the operation and disappeared within 2 months in all cases. After the disappearance of sensory disturbances, we performed postoperative electrophysiological studies in 27 patients (33 hands). Postoperative electrophysiological data were significantly improved in all cases. Patients did not suffer from any serious complications such as motor branch injuries of the median nerve, hypesthesia of the palm, or injuries of the superficial palmar arch. From these results, we conclude that the transverse carpal ligament can be safely incised by this procedure.

Dynamic external finger fixator for fracture dislocation of the proximal interphalangeal joint

The treatment of fracture dislocations of the proximal interphalangeal joint often results in pain and stiffness. A small dynamic external finger fixator was designed to maintain the reduced position of the dislocated middle phalanx and allow early active range-of-motion exercise. Four patients with acute unstable fracture dislocations and three with old malunited fracture dislocations of the proximal interphalangeal joint were treated with this apparatus. The average range of the proximal interphalangeal joint motion with this device was 88 degrees. The average follow-up period was 21 months.

Evaluation of carpal canal pressure in carpal tunnel syndrome

Preoperative electrophysiologic testing and intraoperative carpal canal pressure measurements were performed on 957 hands in 647 patients with clinical signs of carpal tunnel syndrome. Fifty-five symptomatic hands in 48 patients were normal in both distal sensory latency and distal motor latency preoperatively. Carpal canal pressure was, however, significantly elevated compared to control data in all 55 hands. After complete subcutaneous release of the carpal canal using the Universal Subcutaneous Endoscope system, carpal canal pressure was reduced to within the normal control range. Clinical symptoms of carpal tunnel syndrome improved in all 55 hands. Postoperative electrophysiologic data remained within normal range in patients who agreed to receive electrophysiologic examinations.

Three-loop technique for A2 pulley reconstruction

A three-loop technique of secondary A2 pulley reconstruction has been developed by the authors. This method was applied to six fingers of six patients. The average follow-up period was 21 months and ranged from a minimum of 9 months to a maximum of 3 years. Total active motion of metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints improved by 30 degrees on the average from the preoperative 175 degrees to the postoperative 205 degrees. Similarly, tip palm distance showed an improvement of 10 mm on the average from the preoperative 32 mm to the postoperative 22 mm. Satisfactory grip functions were restored for all patients after the secondary pulley reconstruction.

Effects of endoscopic release of the transverse carpal ligament on carpal canal volume

Ten hands in 10 patients with carpal tunnel syndrome were treated by subcutaneous transverse carpal ligament release using the Universal Subcutaneous Endoscope system. We analyzed the morphologic changes of the carpal canal with magnetic resonance imaging (0.064 T) before and after the operation. The axial plane, which includes the beak of the trapezium and the hook of the hamate, was selected for analysis. The soft tissue boundaries of the carpal canal were outlined at the plane. The cross-sectional area of the carpal canal was 232 +/- 49 mm2 before surgery and 320 +/- 108 mm2 after surgery. There was a 33% +/- 15% increase of the carpal canal cross-section after transverse carpal ligament release. The transverse carpal ligament became more outwardly convex after the operation. The endoscopic procedure is effective for increasing the cross-sectional area and volume of the carpal canal.

Transient osteoporosis of the hip. Magnetic resonance imaging.

Magnetic resonance (MR) images of seven hips were reviewed in six patients with transient osteoporosis of the hip. The MR images of the affected joint showed increased joint fluid and diffuse signal abnormalities in the marrow of the femoral head, corresponding to a decreased signal intensity on T1-weighted images and an increased signal intensity on T2-weighted images. The MR images at the time of clinical improvement showed regression of the abnormalities. These MR abnormalities reflect the pathophysiology of this condition.

Complete Endoscopic Carpal Tunnel Release in Long-Term Haemodialysis Patients

The roof of the carpal tunnel (or canal) consists of the distal portion of the flexor retinaculum, the flexor retinaculum (or the transverse carpal ligament) and the proximal portion of the flexor retinaculum. We tried to determine which anatomical structures were relevant to complete endoscopic carpal tunnel decompression in long-term haemodialysis patients with carpal tunnel syndrome. Carpal tunnel pressure was measured using the continuous infusion technique before and after endoscopic release of the flexor retinaculum, distal portion of the flexor retinaculum and the proximal portion of the flexor retinaculum respectively in 257 hands. We concluded that release of the distal portion of the flexor retinaculum, in addition to the flexor retinaculum, is essential for complete carpal tunnel decompression in long-term haemodialysis patients.

MR demonstration of intraosseous beta-2-microglobulin amyloidosis

We present a case of intraosseous beta-2-microglobulin amyloidosis of a patient receiving long-term hemodialysis. Magnetic resonance imaging clearly demonstrated intraosseous amyloid deposits as hypointense masses in the femoral head.

Measurement of carpal canal and median nerve pressure in patients with carpal tunnel syndrome.

Carpal tunnel syndrome is a compression neuropathy wherein the median nerve is compressed inside of the carpal canal. Its diagnosis is made clinically, electrophysiologically, and sometimes by carpal canal pressure measurement. The objective of surgical management of this condition is the decompression of the median nerve. We usually measure carpal canal pressure preoperatively and postoperatively using a continuous infusion technique for diagnoses as well as for postoperative evaluation of decompression following our Universal Subcutaneous Endoscope system procedure. To evaluate whether our procedure effectively decompressed the median nerve, we measured intraneural pressure preoperatively and postoperatively in the resting position, with active power grip, and in the Okutsu test position. Correlation between the carpal canal pressure and intraneural median nerve pressure was statistically analyzed using the Kendall rank correlation coefficient (n = 157 hands). A significant correlation was present preoperatively in resting position and postoperatively with active power grip and in the Okutsu test position. Because of this correlation, we conclude that our endoscopic operative procedure effectively decompresses the median nerve and that simple carpal canal pressure measurement is sufficient to confirm diagnoses and to evaluate the status of postoperative decompression.

Coracoacromial ligament release for shoulder impingement syndrome using the Universal Subcutaneous Endoscope system

We developed a new operative procedure of coracoacromial ligament release for shoulder impingement syndrome. The operative procedure was confirmed by cadaveric studies and applied to clinical cases in 40 shoulders of 37 patients who suffered from shoulder impingement without bony abnormalities. The subacromial space was observed under local anesthesia using the Universal Subcutaneous Endoscope (USE) system on an outpatient basis. A popping phenomenon was observed between the coracoacromial ligament and the greater tuberosity of the humerus, which was covered by the rotator cuff, and the coracoacromial ligament was resected with a rongeur under endoscopic visualization in all shoulders. Resection of the coracoacromial ligament relieved the impingement and clinical signs, as in open or arthroscopic resection of the coracoacromial ligament. Resection of the coracoacromial ligament using the USE system is a safe and less-stressful surgical invasion than open or standard arthroscopic resection of the coracoacromial ligament.