Tsuyoshi Murase | Osaka University (original) (raw)

Papers by Tsuyoshi Murase

Journal of Shoulder and Elbow Surgery, Sep 1, 2019

Background: Contracture of the elbow after obstetric brachial plexus palsy (OBPP) is well known; ... more Background: Contracture of the elbow after obstetric brachial plexus palsy (OBPP) is well known; however, details of the 3-dimensional (3D) morphologic changes in the elbow joint in OBPP have not been clarified. This study aimed to clarify the 3D morphologic changes in the elbow joint by focusing on the distal humerus with flexion contracture in upper OBPP. We tested the hypothesis that the shape of the distal humerus with flexion contracture in upper OBPP is hypoplastic in the trochlea, capitellum, and olecranon fossa. Methods: We retrospectively studied 20 patients with elbow flexion contracture and residual OBPP. The approximate radius of the distal humerus, the shortest distance between the olecranon and coronoid fossa, and the size of the olecranon fossa were measured and compared between the affected and normal sides using 3D bone models to assess the distal humerus morphology. Results: The average radius of the distal humerus was smaller on the affected side than on the normal side. Furthermore, the average distance between the olecranon and coronoid fossa was greater and the average size of the olecranon fossa was smaller on the affected side than on the normal side. The size of the distal humerus was significantly smaller and the olecranon fossa was significantly shallower on the affected side. Conclusions: Consistent with our original hypothesis, the distal humerus with flexion contracture in upper OBPP was hypoplastic. The shallow olecranon fossa might prevent full extension of the elbow even though soft tissue contracture release is performed. We recommend evaluation of the morphology of the olecranon fossa to determine the treatment plan for elbow flexion contracture with OBPP.

The Journal of Hand Surgery, Sep 1, 2018

Figure 46-2AB: (A) Day 0 intraoperative nerve stimulation data indicates no change in pre-and pos... more Figure 46-2AB: (A) Day 0 intraoperative nerve stimulation data indicates no change in pre-and postsham values in SC nerves. A statistically significant increase in stimulation was observed between pre-and poststretch values in HS nerves. (B) A comparison of intraoperative nerve stimulation values at postintervention day 0 and at day 84 indicates a statistically significant recovery of stimulation values in HS nerves. No change was observed in SC nerves.

PubMed, Dec 3, 2011

ABSTRACT -

Journal of Orthopaedic Science, Sep 1, 2019

The journal of bone and joint surgery, Apr 1, 2007

We have measured the three-dimensional patterns of carpal deformity in 20 wrists in 20 rheumatoid... more We have measured the three-dimensional patterns of carpal deformity in 20 wrists in 20 rheumatoid patients in which the carpal bones were shifted ulnarwards on plain radiography. Three-dimensional bone models of the carpus and radius were created by computerised tomography with the wrist in the neutral position. The location of the centroids and rotational angle of each carpal bone relative to the radius were calculated and compared with those of ten normal wrists. In the radiocarpal joint, the proximal row was flexed and the centroids of all carpal bones translocated in an ulnar, proximal and volar direction with loss of congruity. In the midcarpal joint, the distal row was extended and congruity generally well preserved. These findings may facilitate more positive use of radiocarpal fusion alone for the deformed rheumatoid wrist.

Journal of Bone and Joint Surgery, American Volume, Nov 20, 2013

Cubitus varus deformity after a supracondylar fracture classically includes varus, extension, and... more Cubitus varus deformity after a supracondylar fracture classically includes varus, extension, and internal rotation components. However, to our knowledge, no reliable surgical method for three-dimensional corrective osteotomy has been established. We developed an intraoperative guide system involving a custom-made surgical template designed on the basis of a three-dimensional computer simulation incorporating computed tomography (CT) data. We aimed to investigate the feasibility of this novel technique for correcting cubitus varus deformity. Thirty consecutive patients (twenty-three males and seven females) with a cubitus varus deformity resulting from the malunion of a distal humeral supracondylar fracture were included in this study. Between October 2003 and May 2011, the patients underwent a three-dimensional corrective osteotomy with use of a custom-made surgical template. The patients were then followed for a minimum of twelve months. We evaluated radiographic parameters, including the humerus-elbow-wrist angle and tilting angle, as well as the ranges of motion of the elbow and shoulder at the time of the most recent follow-up. An overall clinical evaluation was performed. Bone union was achieved at a mean of four months after surgery. The mean humerus-elbow-wrist angle and tilting angle on the affected side improved significantly from 18.2° (varus) and 25.0°, respectively, before surgery, to 5.8° (valgus) and 38.0°, respectively, after surgery. Hyperextension of the elbow and internal rotation of the shoulder were normalized in all patients. Early plate breakage was observed in one patient. One patient had mild recurrence of varus deformity. Twenty-seven patients had an excellent result, three had a good result, and none had a poor result. Three-dimensional corrective osteotomy with the use of a custom-made surgical template that is designed and produced on the basis of computer simulation is a feasible and useful treatment option for cubitus varus deformity.

Osteoarthritis and Cartilage, Dec 1, 2020

Objective: To quantify the spatial distributions of cartilage and subchondral bone thickness of t... more Objective: To quantify the spatial distributions of cartilage and subchondral bone thickness of the distal radius. Design: Using 17 cadaveric wrists, three types of 3-dimensional models were created: a cartilage-bone model, obtained by laser scanning; a bone model, rescanned after dissolving the cartilage; and a subchondral bone model, obtained using computed tomography. By superimposing the bone model onto the cartilagebone and the subchondral bone models, the cartilage and subchondral bone thickness were determined. Measurements along with the spatial distribution were made at fixed anatomic points including the scaphoid and lunate fossa, sigmoid notch and interfossal ridge, and compared at each of these four regions. Results: Cartilage thickness of the interfossal ridge (0.89 ± 0.23 mm) had a larger average thickness compared to that of the scaphoid fossa (0.70 ± 0.18 mm; p ¼ 0.004), lunate fossa (0.75 ± 0.17 mm; p ¼ 0.044) and sigmoid notch (0.64 ± 0.13 mm; p < 0.001). Subchondral bone was found to be thickest at the scaphoid (2.18 ± 0.72 mm) and lunate fossae (1.94 ± 0.93 mm), which were both thicker than that of sigmoid notch (1.63 ± 1.06 mm: vs scaphoid fossa, p ¼ 0.020) or interfossal ridge (1.54 ± 0.84 mm: vs scaphoid fossa, p ¼ 0.004; vs lunate fossa, p ¼ 0.048). In the volar-ulnar sub-regions of the scaphoid and lunate fossa, the subchondral bone thickened. Conclusions: Our data can be applied when treating distal radius fractures. Cartilage thickness was less than 1 mm across the articular surface, which may give an insight into threshold for an acceptable range of step-offs. The combined findings of subchondral bone appreciate the importance of the volar-ulnar corner of the distal radius in the volar locking plate fixation.

Archives of Orthopaedic and Trauma Surgery, Aug 17, 2016

Introduction Intra-articular malunion after fractures of the distal humerus can cause pain, stiff... more Introduction Intra-articular malunion after fractures of the distal humerus can cause pain, stiffness and, consequently, osteoarthritis in the long run. Although corrective osteotomy for intra-articular malunion has been reported, it is still technically challenging and needs careful preoperative evaluation and planning. Here, we present two cases of corrective osteotomy assisted by preoperative three-dimensional (3-D) computer simulation. Materials and methods We present two cases of malunited intra-articular fracture of the distal humerus, which was treated by corrective osteotomy with the aid of 3-D computer simulation. One case was initially treated with closed reduction and pinning, and the other was initially treated with open reduction and internal fixation. Both of them had pain and severely limited range of motion in the elbow due to intra-articular malunion. 3-D models of the bilateral humeri were created on a computer using computed tomography (CT) data. The deformity was analyzed by superimposing the model of the affected humerus on the mirrored model of the contralateral normal humerus. Osteotomy, reduction and fixation were simulated preoperatively on the computer. The actual surgery was performed exactly according to the preoperative 3-D computer simulation. Results The operative procedures were performed successfully according to the computer simulation. Range-ofmotion exercises started 3 days and immediately after the surgery in cases 1 and 2, respectively. Two years after surgery, there were no complaints of pain or instability. The range of elbow motion was 5°-140°and 15°-125°in cases 1 and 2, respectively. Plain radiographs and CT scans showed good reconstruction of the articular surface. Conclusion 3-D computer simulations can be useful in preoperative planning for intra-articular corrective osteotomy for complex malunion of the distal humerus.

The Journal of Hand Surgery, Feb 1, 2018

Purpose This study primarily aimed to demonstrate the screw-home rotation of the thumb carpometac... more Purpose This study primarily aimed to demonstrate the screw-home rotation of the thumb carpometacarpal (CMC) joint and the function of surrounding ligaments during thumb oppositional motion. Methods A 3-dimensional kinematic analysis of the thumb CMC joint was conducted using data derived from computed tomography of 9 healthy volunteers. Scans were obtained in the neutral forearm and wrist position and the thumb in maximum radial abduction, maximum palmar abduction, and maximum opposition. The movements of the first metacarpal and the palmar and dorsal bases on the trapezium during thumb oppositional motion from radial abduction through palmar abduction were quantified using a coordinate system originating on the trapezium. In addition to the kinematic analyses, the length of virtual ligaments, including the anterior oblique, ulnar collateral, dorsal radial, dorsal central (DCL), and posterior oblique ligament (POL), were calculated at each thumb position. Results From radial abduction to opposition of the thumb through palmar abduction, the first metacarpal was abducted, internally rotated, and flexed on the trapezium. The palmar base of the first metacarpal moved in the palmar-ulnar direction, and the dorsal base moved in the palmar-distal direction along the concave surface of the trapezium. Although the DCL and POL lengthened, the lengths of other ligaments did not change significantly. Conclusions During thumb oppositional motion, internal rotation of the first metacarpal occurred, with the palmar base rotating primarily with respect to the dorsal base. The DCL and POL may be strained in thumb functional positions. Clinical relevance Kinematic variables indicated a screw-home rotation of the thumb CMC joint and the contribution of the dorsal ligaments to the stability of the rotation on the pivot point.

International Journal of Molecular Sciences, May 7, 2018

Ultra-fine bubbles (<200 nm in diameter) have several unique properties and have been tested in v... more Ultra-fine bubbles (<200 nm in diameter) have several unique properties and have been tested in various medical fields. The purpose of this study was to investigate the effects of oxygen ultra-fine bubbles (OUBs) on a sciatic nerve crush injury (SNC) model rats. Rats were intraperitoneally injected with 1.5 mL saline, OUBs diluted in saline, or nitrogen ultra-fine bubbles (NUBs) diluted in saline three times per week for 4 weeks in four groups: (1) control, (sham operation + saline); (2) SNC, (crush + saline); (3) SNC+OUB, (crush + OUB-saline); (4) SNC+NUB, (crush + NUB-saline). The effects of the OUBs on dorsal root ganglion (DRG) neurons and Schwann cells (SCs) were examined by serial dilution of OUB medium in vitro. Sciatic functional index, paw withdrawal thresholds, nerve conduction velocity, and myelinated axons were significantly decreased in the SNC group compared to the control group; these parameters were significantly improved in the SNC+OUB group, although NUB treatment did not affect these parameters. In vitro, OUBs significantly promoted neurite outgrowth in DRG neurons by activating AKT signaling and SC proliferation by activating ERK1/2 and JNK/c-JUN signaling. OUBs may improve nerve dysfunction in SNC rats by promoting neurite outgrowth in DRG neurons and SC proliferation.

The bone & joint journal, Feb 1, 2014

We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer... more We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer simulation of CT scans of the elbow in assisting their arthroscopic removal in patients with osteoarthritis of the elbow. A total of 20 patients were treated (19 men and one woman, mean age 38 years (19 to 55)) and followed for a mean of 25 months (24 to 29). We located the impinging osteophytes dynamically using computerised three-dimensional models of the elbow based on CT data in three positions of flexion of the elbow. These were then removed arthroscopically and a capsular release was performed. The mean loss of extension improved from 23° (10° to 45°) pre-operatively to 9° (0° to 25°) post-operatively, and the mean flexion improved from 121° (80° to 140°) pre-operatively to 130° (110° to 145°) post-operatively. The mean Mayo Elbow Performance Score improved from 62 (30 to 85) to 95 (70 to 100) post-operatively. All patients had pain in the elbow preoperatively which disappeared or decreased post-operatively. According to their Mayo scores, 14 patients had an excellent clinical outcome and six a good outcome; 15 were very satisfied and five were satisfied with their post-operative outcome. We recommend this technique in the surgical management of patients with osteoarthritis of the elbow.

Journal of Orthopaedic Science, Feb 1, 2023

Archives of Orthopaedic and Trauma Surgery, Dec 9, 2016

In the original article, co-author's given name and family name are represented incorrectly. The ... more In the original article, co-author's given name and family name are represented incorrectly. The correct name should be Kunihiro Oka.

Jbjs Essential Surgical Techniques, Mar 26, 2014

Journal of Hand Surgery (European Volume), 2018

Orthopaedic Proceedings, Feb 21, 2018

When total ankle arthroplasty (TAA) is performed, although tibial osteotomy is instructed to be p... more When total ankle arthroplasty (TAA) is performed, although tibial osteotomy is instructed to be perpendicular to long axis of tibia, there is no established index for the talar bone corrective osteotomy. Then, we have been deciding the correction angle at the plan for adjustment of the loading axis through whole lower extremities. We studied 17 TAA cases with rheumatoid arthritis (RA). X-ray picture of hip to calcaneus view (hip joint to tip of the calcaneus) defined to show more approximated loading axis has been referred for the preoperative planning. Furthermore, the data of correction angle has been reflected to pre-designed custom-made surgical guide. If soft tissue balance was not acceptable, malleolar sliding osteotomy was added. The distance between the centre of ankle joint and the axis (preD) was measured (mm) preoperatively, and the distance between the centre of prosthesis and the axis (postD) was measured postoperatively. Next, the tilting angle between tibial and talar components (defined as the index of prosthesis edge loading) were measured with X-rays during standing. Tibio Calcaneal (TC) angle was also measured pre and postoperatively. TC angle was significantly improved from 8.3±6.0° to 3.5±3.6° postoperatively (P=0.028). PreD was 12.9±9.6mm, and that was significantly improved to 4.8±6.3mm (postD) (P=0.006). Within 17 cases, 8 cases showed 0–1mm of postD, 4 cases showed 1–5mm of postD, remaining 5 cases concomitant subtalar fusion with severe valgus and varus hindfoot deformity showed over 8mm of postD. All of the 12 cases showing within 5mm of postD indicated within 13mm of preD. The tilting angle between components was 0.17±0.37° postoperatively. Taken together, pre-designed corrective talar osteotomy based on preoperative planning using hip to calcaneus view was useful to adjust the mechanical axis for replaced ankle joint in RA cases. Furthermore, after surgery, the hip to calcaneus view was useful to evaluate post-operative mechanical axis of whole lower extremities.

The Journal of Hand Surgery, Jun 1, 2017

Purpose In nonsurgical treatment for acute undisplaced or minimally displaced scaphoid waist frac... more Purpose In nonsurgical treatment for acute undisplaced or minimally displaced scaphoid waist fractures, immobilization of both wrist and thumb can be an option. However, in vivo scaphoid motion during forearm and thumb motion with the wrist immobilized in a cast has not been measured. Therefore, we examined the in vivo kinematics of the scaphoid during forearm and thumb motion with cast immobilization. Methods Ten healthy right wrists of 10 male volunteers were included. These wrists were immobilized in a short-arm spica cast with the thumb in a position of volar abduction and then were scanned with the forearm in supination, neutral rotation, and pronation using computed tomography. Next, these wrists were scanned with a forearm gauntlet cast in place with the thumb abducted radially and opposed with the forearm positioned in neutral rotation. From these data, the 3-dimensional position of the third metacarpal and scaphoid was analyzed. Results From forearm supination to pronation, the scaphoid showed 0.2 radial deviation, 0.4 pronation, and 8.3 extension. The third metacarpal showed 14.6 ulnar deviation, 6.5 pronation, and 1.6 flexion. During thumb opposition from radial abduction, the scaphoid showed 2.9 radial deviation, 0.4 supination, and 7.2 extension and the third metacarpal showed 4.5 ulnar deviation, 2.8 pronation, and 5.5 extension. Conclusions The scaphoid was not completely immobilized by either cast. However, the scaphoid motion during forearm and thumb motion was not significant. Clinical relevance Several high-quality studies have shown that undisplaced or minimally displaced scaphoid waist fractures can be successfully treated with casts. Movement of scaphoid and wrist during forearm rotation or thumb motion with a cast may not be sufficient to have a negative impact on the outcome of scaphoid fracture using a cast.

Journal of Hand Surgery (European Volume), 2018

Scientific Reports, 2021

The purpose of the study was to develop a deep learning network for estimating and constructing h... more The purpose of the study was to develop a deep learning network for estimating and constructing highly accurate 3D bone models directly from actual X-ray images and to verify its accuracy. The data used were 173 computed tomography (CT) images and 105 actual X-ray images of a healthy wrist joint. To compensate for the small size of the dataset, digitally reconstructed radiography (DRR) images generated from CT were used as training data instead of actual X-ray images. The DRR-like images were generated from actual X-ray images in the test and adapted to the network, and high-accuracy estimation of a 3D bone model from a small data set was possible. The 3D shape of the radius and ulna were estimated from actual X-ray images with accuracies of 1.05 ± 0.36 and 1.45 ± 0.41 mm, respectively.

Journal of Shoulder and Elbow Surgery, Sep 1, 2019

Background: Contracture of the elbow after obstetric brachial plexus palsy (OBPP) is well known; ... more Background: Contracture of the elbow after obstetric brachial plexus palsy (OBPP) is well known; however, details of the 3-dimensional (3D) morphologic changes in the elbow joint in OBPP have not been clarified. This study aimed to clarify the 3D morphologic changes in the elbow joint by focusing on the distal humerus with flexion contracture in upper OBPP. We tested the hypothesis that the shape of the distal humerus with flexion contracture in upper OBPP is hypoplastic in the trochlea, capitellum, and olecranon fossa. Methods: We retrospectively studied 20 patients with elbow flexion contracture and residual OBPP. The approximate radius of the distal humerus, the shortest distance between the olecranon and coronoid fossa, and the size of the olecranon fossa were measured and compared between the affected and normal sides using 3D bone models to assess the distal humerus morphology. Results: The average radius of the distal humerus was smaller on the affected side than on the normal side. Furthermore, the average distance between the olecranon and coronoid fossa was greater and the average size of the olecranon fossa was smaller on the affected side than on the normal side. The size of the distal humerus was significantly smaller and the olecranon fossa was significantly shallower on the affected side. Conclusions: Consistent with our original hypothesis, the distal humerus with flexion contracture in upper OBPP was hypoplastic. The shallow olecranon fossa might prevent full extension of the elbow even though soft tissue contracture release is performed. We recommend evaluation of the morphology of the olecranon fossa to determine the treatment plan for elbow flexion contracture with OBPP.

The Journal of Hand Surgery, Sep 1, 2018

Figure 46-2AB: (A) Day 0 intraoperative nerve stimulation data indicates no change in pre-and pos... more Figure 46-2AB: (A) Day 0 intraoperative nerve stimulation data indicates no change in pre-and postsham values in SC nerves. A statistically significant increase in stimulation was observed between pre-and poststretch values in HS nerves. (B) A comparison of intraoperative nerve stimulation values at postintervention day 0 and at day 84 indicates a statistically significant recovery of stimulation values in HS nerves. No change was observed in SC nerves.

PubMed, Dec 3, 2011

ABSTRACT -

Journal of Orthopaedic Science, Sep 1, 2019

The journal of bone and joint surgery, Apr 1, 2007

We have measured the three-dimensional patterns of carpal deformity in 20 wrists in 20 rheumatoid... more We have measured the three-dimensional patterns of carpal deformity in 20 wrists in 20 rheumatoid patients in which the carpal bones were shifted ulnarwards on plain radiography. Three-dimensional bone models of the carpus and radius were created by computerised tomography with the wrist in the neutral position. The location of the centroids and rotational angle of each carpal bone relative to the radius were calculated and compared with those of ten normal wrists. In the radiocarpal joint, the proximal row was flexed and the centroids of all carpal bones translocated in an ulnar, proximal and volar direction with loss of congruity. In the midcarpal joint, the distal row was extended and congruity generally well preserved. These findings may facilitate more positive use of radiocarpal fusion alone for the deformed rheumatoid wrist.

Journal of Bone and Joint Surgery, American Volume, Nov 20, 2013

Cubitus varus deformity after a supracondylar fracture classically includes varus, extension, and... more Cubitus varus deformity after a supracondylar fracture classically includes varus, extension, and internal rotation components. However, to our knowledge, no reliable surgical method for three-dimensional corrective osteotomy has been established. We developed an intraoperative guide system involving a custom-made surgical template designed on the basis of a three-dimensional computer simulation incorporating computed tomography (CT) data. We aimed to investigate the feasibility of this novel technique for correcting cubitus varus deformity. Thirty consecutive patients (twenty-three males and seven females) with a cubitus varus deformity resulting from the malunion of a distal humeral supracondylar fracture were included in this study. Between October 2003 and May 2011, the patients underwent a three-dimensional corrective osteotomy with use of a custom-made surgical template. The patients were then followed for a minimum of twelve months. We evaluated radiographic parameters, including the humerus-elbow-wrist angle and tilting angle, as well as the ranges of motion of the elbow and shoulder at the time of the most recent follow-up. An overall clinical evaluation was performed. Bone union was achieved at a mean of four months after surgery. The mean humerus-elbow-wrist angle and tilting angle on the affected side improved significantly from 18.2° (varus) and 25.0°, respectively, before surgery, to 5.8° (valgus) and 38.0°, respectively, after surgery. Hyperextension of the elbow and internal rotation of the shoulder were normalized in all patients. Early plate breakage was observed in one patient. One patient had mild recurrence of varus deformity. Twenty-seven patients had an excellent result, three had a good result, and none had a poor result. Three-dimensional corrective osteotomy with the use of a custom-made surgical template that is designed and produced on the basis of computer simulation is a feasible and useful treatment option for cubitus varus deformity.

Osteoarthritis and Cartilage, Dec 1, 2020

Objective: To quantify the spatial distributions of cartilage and subchondral bone thickness of t... more Objective: To quantify the spatial distributions of cartilage and subchondral bone thickness of the distal radius. Design: Using 17 cadaveric wrists, three types of 3-dimensional models were created: a cartilage-bone model, obtained by laser scanning; a bone model, rescanned after dissolving the cartilage; and a subchondral bone model, obtained using computed tomography. By superimposing the bone model onto the cartilagebone and the subchondral bone models, the cartilage and subchondral bone thickness were determined. Measurements along with the spatial distribution were made at fixed anatomic points including the scaphoid and lunate fossa, sigmoid notch and interfossal ridge, and compared at each of these four regions. Results: Cartilage thickness of the interfossal ridge (0.89 ± 0.23 mm) had a larger average thickness compared to that of the scaphoid fossa (0.70 ± 0.18 mm; p ¼ 0.004), lunate fossa (0.75 ± 0.17 mm; p ¼ 0.044) and sigmoid notch (0.64 ± 0.13 mm; p < 0.001). Subchondral bone was found to be thickest at the scaphoid (2.18 ± 0.72 mm) and lunate fossae (1.94 ± 0.93 mm), which were both thicker than that of sigmoid notch (1.63 ± 1.06 mm: vs scaphoid fossa, p ¼ 0.020) or interfossal ridge (1.54 ± 0.84 mm: vs scaphoid fossa, p ¼ 0.004; vs lunate fossa, p ¼ 0.048). In the volar-ulnar sub-regions of the scaphoid and lunate fossa, the subchondral bone thickened. Conclusions: Our data can be applied when treating distal radius fractures. Cartilage thickness was less than 1 mm across the articular surface, which may give an insight into threshold for an acceptable range of step-offs. The combined findings of subchondral bone appreciate the importance of the volar-ulnar corner of the distal radius in the volar locking plate fixation.

Archives of Orthopaedic and Trauma Surgery, Aug 17, 2016

Introduction Intra-articular malunion after fractures of the distal humerus can cause pain, stiff... more Introduction Intra-articular malunion after fractures of the distal humerus can cause pain, stiffness and, consequently, osteoarthritis in the long run. Although corrective osteotomy for intra-articular malunion has been reported, it is still technically challenging and needs careful preoperative evaluation and planning. Here, we present two cases of corrective osteotomy assisted by preoperative three-dimensional (3-D) computer simulation. Materials and methods We present two cases of malunited intra-articular fracture of the distal humerus, which was treated by corrective osteotomy with the aid of 3-D computer simulation. One case was initially treated with closed reduction and pinning, and the other was initially treated with open reduction and internal fixation. Both of them had pain and severely limited range of motion in the elbow due to intra-articular malunion. 3-D models of the bilateral humeri were created on a computer using computed tomography (CT) data. The deformity was analyzed by superimposing the model of the affected humerus on the mirrored model of the contralateral normal humerus. Osteotomy, reduction and fixation were simulated preoperatively on the computer. The actual surgery was performed exactly according to the preoperative 3-D computer simulation. Results The operative procedures were performed successfully according to the computer simulation. Range-ofmotion exercises started 3 days and immediately after the surgery in cases 1 and 2, respectively. Two years after surgery, there were no complaints of pain or instability. The range of elbow motion was 5°-140°and 15°-125°in cases 1 and 2, respectively. Plain radiographs and CT scans showed good reconstruction of the articular surface. Conclusion 3-D computer simulations can be useful in preoperative planning for intra-articular corrective osteotomy for complex malunion of the distal humerus.

The Journal of Hand Surgery, Feb 1, 2018

Purpose This study primarily aimed to demonstrate the screw-home rotation of the thumb carpometac... more Purpose This study primarily aimed to demonstrate the screw-home rotation of the thumb carpometacarpal (CMC) joint and the function of surrounding ligaments during thumb oppositional motion. Methods A 3-dimensional kinematic analysis of the thumb CMC joint was conducted using data derived from computed tomography of 9 healthy volunteers. Scans were obtained in the neutral forearm and wrist position and the thumb in maximum radial abduction, maximum palmar abduction, and maximum opposition. The movements of the first metacarpal and the palmar and dorsal bases on the trapezium during thumb oppositional motion from radial abduction through palmar abduction were quantified using a coordinate system originating on the trapezium. In addition to the kinematic analyses, the length of virtual ligaments, including the anterior oblique, ulnar collateral, dorsal radial, dorsal central (DCL), and posterior oblique ligament (POL), were calculated at each thumb position. Results From radial abduction to opposition of the thumb through palmar abduction, the first metacarpal was abducted, internally rotated, and flexed on the trapezium. The palmar base of the first metacarpal moved in the palmar-ulnar direction, and the dorsal base moved in the palmar-distal direction along the concave surface of the trapezium. Although the DCL and POL lengthened, the lengths of other ligaments did not change significantly. Conclusions During thumb oppositional motion, internal rotation of the first metacarpal occurred, with the palmar base rotating primarily with respect to the dorsal base. The DCL and POL may be strained in thumb functional positions. Clinical relevance Kinematic variables indicated a screw-home rotation of the thumb CMC joint and the contribution of the dorsal ligaments to the stability of the rotation on the pivot point.

International Journal of Molecular Sciences, May 7, 2018

Ultra-fine bubbles (<200 nm in diameter) have several unique properties and have been tested in v... more Ultra-fine bubbles (<200 nm in diameter) have several unique properties and have been tested in various medical fields. The purpose of this study was to investigate the effects of oxygen ultra-fine bubbles (OUBs) on a sciatic nerve crush injury (SNC) model rats. Rats were intraperitoneally injected with 1.5 mL saline, OUBs diluted in saline, or nitrogen ultra-fine bubbles (NUBs) diluted in saline three times per week for 4 weeks in four groups: (1) control, (sham operation + saline); (2) SNC, (crush + saline); (3) SNC+OUB, (crush + OUB-saline); (4) SNC+NUB, (crush + NUB-saline). The effects of the OUBs on dorsal root ganglion (DRG) neurons and Schwann cells (SCs) were examined by serial dilution of OUB medium in vitro. Sciatic functional index, paw withdrawal thresholds, nerve conduction velocity, and myelinated axons were significantly decreased in the SNC group compared to the control group; these parameters were significantly improved in the SNC+OUB group, although NUB treatment did not affect these parameters. In vitro, OUBs significantly promoted neurite outgrowth in DRG neurons by activating AKT signaling and SC proliferation by activating ERK1/2 and JNK/c-JUN signaling. OUBs may improve nerve dysfunction in SNC rats by promoting neurite outgrowth in DRG neurons and SC proliferation.

The bone & joint journal, Feb 1, 2014

We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer... more We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer simulation of CT scans of the elbow in assisting their arthroscopic removal in patients with osteoarthritis of the elbow. A total of 20 patients were treated (19 men and one woman, mean age 38 years (19 to 55)) and followed for a mean of 25 months (24 to 29). We located the impinging osteophytes dynamically using computerised three-dimensional models of the elbow based on CT data in three positions of flexion of the elbow. These were then removed arthroscopically and a capsular release was performed. The mean loss of extension improved from 23° (10° to 45°) pre-operatively to 9° (0° to 25°) post-operatively, and the mean flexion improved from 121° (80° to 140°) pre-operatively to 130° (110° to 145°) post-operatively. The mean Mayo Elbow Performance Score improved from 62 (30 to 85) to 95 (70 to 100) post-operatively. All patients had pain in the elbow preoperatively which disappeared or decreased post-operatively. According to their Mayo scores, 14 patients had an excellent clinical outcome and six a good outcome; 15 were very satisfied and five were satisfied with their post-operative outcome. We recommend this technique in the surgical management of patients with osteoarthritis of the elbow.

Journal of Orthopaedic Science, Feb 1, 2023

Archives of Orthopaedic and Trauma Surgery, Dec 9, 2016

In the original article, co-author's given name and family name are represented incorrectly. The ... more In the original article, co-author's given name and family name are represented incorrectly. The correct name should be Kunihiro Oka.

Jbjs Essential Surgical Techniques, Mar 26, 2014

Journal of Hand Surgery (European Volume), 2018

Orthopaedic Proceedings, Feb 21, 2018

When total ankle arthroplasty (TAA) is performed, although tibial osteotomy is instructed to be p... more When total ankle arthroplasty (TAA) is performed, although tibial osteotomy is instructed to be perpendicular to long axis of tibia, there is no established index for the talar bone corrective osteotomy. Then, we have been deciding the correction angle at the plan for adjustment of the loading axis through whole lower extremities. We studied 17 TAA cases with rheumatoid arthritis (RA). X-ray picture of hip to calcaneus view (hip joint to tip of the calcaneus) defined to show more approximated loading axis has been referred for the preoperative planning. Furthermore, the data of correction angle has been reflected to pre-designed custom-made surgical guide. If soft tissue balance was not acceptable, malleolar sliding osteotomy was added. The distance between the centre of ankle joint and the axis (preD) was measured (mm) preoperatively, and the distance between the centre of prosthesis and the axis (postD) was measured postoperatively. Next, the tilting angle between tibial and talar components (defined as the index of prosthesis edge loading) were measured with X-rays during standing. Tibio Calcaneal (TC) angle was also measured pre and postoperatively. TC angle was significantly improved from 8.3±6.0° to 3.5±3.6° postoperatively (P=0.028). PreD was 12.9±9.6mm, and that was significantly improved to 4.8±6.3mm (postD) (P=0.006). Within 17 cases, 8 cases showed 0–1mm of postD, 4 cases showed 1–5mm of postD, remaining 5 cases concomitant subtalar fusion with severe valgus and varus hindfoot deformity showed over 8mm of postD. All of the 12 cases showing within 5mm of postD indicated within 13mm of preD. The tilting angle between components was 0.17±0.37° postoperatively. Taken together, pre-designed corrective talar osteotomy based on preoperative planning using hip to calcaneus view was useful to adjust the mechanical axis for replaced ankle joint in RA cases. Furthermore, after surgery, the hip to calcaneus view was useful to evaluate post-operative mechanical axis of whole lower extremities.

The Journal of Hand Surgery, Jun 1, 2017

Purpose In nonsurgical treatment for acute undisplaced or minimally displaced scaphoid waist frac... more Purpose In nonsurgical treatment for acute undisplaced or minimally displaced scaphoid waist fractures, immobilization of both wrist and thumb can be an option. However, in vivo scaphoid motion during forearm and thumb motion with the wrist immobilized in a cast has not been measured. Therefore, we examined the in vivo kinematics of the scaphoid during forearm and thumb motion with cast immobilization. Methods Ten healthy right wrists of 10 male volunteers were included. These wrists were immobilized in a short-arm spica cast with the thumb in a position of volar abduction and then were scanned with the forearm in supination, neutral rotation, and pronation using computed tomography. Next, these wrists were scanned with a forearm gauntlet cast in place with the thumb abducted radially and opposed with the forearm positioned in neutral rotation. From these data, the 3-dimensional position of the third metacarpal and scaphoid was analyzed. Results From forearm supination to pronation, the scaphoid showed 0.2 radial deviation, 0.4 pronation, and 8.3 extension. The third metacarpal showed 14.6 ulnar deviation, 6.5 pronation, and 1.6 flexion. During thumb opposition from radial abduction, the scaphoid showed 2.9 radial deviation, 0.4 supination, and 7.2 extension and the third metacarpal showed 4.5 ulnar deviation, 2.8 pronation, and 5.5 extension. Conclusions The scaphoid was not completely immobilized by either cast. However, the scaphoid motion during forearm and thumb motion was not significant. Clinical relevance Several high-quality studies have shown that undisplaced or minimally displaced scaphoid waist fractures can be successfully treated with casts. Movement of scaphoid and wrist during forearm rotation or thumb motion with a cast may not be sufficient to have a negative impact on the outcome of scaphoid fracture using a cast.

Journal of Hand Surgery (European Volume), 2018

Scientific Reports, 2021

The purpose of the study was to develop a deep learning network for estimating and constructing h... more The purpose of the study was to develop a deep learning network for estimating and constructing highly accurate 3D bone models directly from actual X-ray images and to verify its accuracy. The data used were 173 computed tomography (CT) images and 105 actual X-ray images of a healthy wrist joint. To compensate for the small size of the dataset, digitally reconstructed radiography (DRR) images generated from CT were used as training data instead of actual X-ray images. The DRR-like images were generated from actual X-ray images in the test and adapted to the network, and high-accuracy estimation of a 3D bone model from a small data set was possible. The 3D shape of the radius and ulna were estimated from actual X-ray images with accuracies of 1.05 ± 0.36 and 1.45 ± 0.41 mm, respectively.