Kensuke Ochi

Use of isolated mature osteoblasts in abundance acts as desired-shaped bone regeneration in combination with a modified poly-DL-lactic-co-glycolic acid (PLGA)-collagen sponge

Controlled regeneration of bone or cartilage has recently begun to facilitate a host of novel clinical treatments. An osteoblast line, which we isolated is able to form new bone matrix in vivo within 2 days and exhibits a mature osteoblast phenotype both in vitro and in vivo. Using these cells, we show that cuboidal bones can be generated into a predesigned shaped‐bone with high‐density bone trabeculae when used in combination with a modified poly‐DL‐lactic‐co‐glycolic acid (PLGA)‐collagen sponge. PLGA coated with collagen gel serves as a good scaffold for osteoblasts. These results indicate that mature osteoblasts, in combination with a scaffold such as PLGA‐collagen sponge, show promise for use in a custom‐shaped bone regeneration tool for both basic research into osteogenesis and for development of therapeutic applications.

Surgical treatment of spontaneous posterior interosseous nerve palsy: a retrospective study of 50 cases.

We have reviewed 38 surgically treated cases of spontaneous posterior interosseous nerve palsy in 38 patients with a mean age of 43 years (13 to 68) in order to identify clinical factors associated with its prognosis. Interfascicular neurolysis was performed at a mean of 13 months (1 to 187) after the onset of symptoms. The mean follow-up was 21 months (5.5 to 221). Medical Research Council muscle power of more than grade 4 was considered to be a good result. A further 12 cases in ten patients were treated conservatively and assessed similarly. Of the 30 cases treated surgically with available outcome data, the result of interfascicular neurolysis was significantly better in patients < 50 years old (younger group (18 nerves); good: 13 nerves (72%), poor: five nerves (28%)) than in cases > 50 years old (older group (12 nerves); good: one nerve (8%), poor: 11 nerves (92%)) (p < 0.001). A pre-operative period of less than seven months was also associated with a good result in the younger group (p = 0.01). The older group had a poor result regardless of the pre-operative delay. Our recommended therapeutic approach therefore is to perform interfascicular neurolysis if the patient is < 50 years of age, and the pre-operative delay is < seven months. If the patient is > 50 years of age with no sign of recovery for seven months, or in the younger group with a pre-operative delay of more than a year, we advise interfascicular neurolysis together with tendon transfer as the primary surgical procedure.

Three-dimensional anthropometric analysis of the glenohumeral joint in a normal Japanese population

BACKGROUND An understanding of normal glenohumeral geometry is important for anatomical reconstruction in shoulder arthroplasty. Unfortunately, the details of the glenohumeral joint in Asian populations have not been sufficiently evaluated. The purpose of this study was to evaluate the 3-dimensional geometry of the glenohumeral joint in the normal Japanese population and to clarify its morphologic features. METHODS Anthropometric analysis of the glenohumeral joint was performed using computed tomography scans of 160 normal shoulders from healthy Japanese volunteers. The glenohumeral dimensions and orientation were analyzed 3-dimensionally. Sex differences and correlations between sides and among the respective parameters in the glenohumeral dimensions were evaluated. RESULTS The normal Japanese humeral head has an average width of 41.4 mm, thickness of 13.2 mm, diameter of 42.9 mm, retroversion of 32°, and inclination of 135°. The glenoid has an average height of 31.5 mm, width of 23.1 mm, diameter of 62.0 mm, retroversion of 0°, and inferior inclination of 2°. The values of the glenohumeral dimensions were uniform in men and women, and the humeral head and glenoid were larger in men than in women. The glenohumeral size was well correlated between the 2 sides, and there were direct correlations among the heights, humeral length, humeral head size, and glenoid size. CONCLUSIONS The present study revealed the glenohumeral geometry in the normal Japanese population. The present results would be useful to determine the size of implants and to improve the design of shoulder prostheses that reflect the normal anatomy of the Asian glenohumeral joint.

Fascicular constrictions in patients with spontaneous palsy of the anterior interosseous nerve and the posterior interosseous nerve.

Abstract There is no definition for fascicular constrictions of the spontaneous anterior interosseous nerve palsy (sAINP) and spontaneous posterior interosseous nerve palsy (sPINP). One surgeon has evaluated his findings in our 32 patients of sAINP/sPINP using either photographs or video tapes and proposed a definition. All patients had interfascicular neurolysis, and 87 case reports of “fascicular constriction” were also evaluated. Fascicular constriction was defined as every instance of thinning in the fascicle regardless to its extent. Thinning as a result of extrinsic compression was excluded. The fascicular constrictions were divided into four types: recessed, recessed-bulging, rotation, and rotation-bulging constriction. Two independent surgeons went through our findings to verify their repeatability. The relation between the fascicular constrictions and age at the onset of palsy was evaluated using Students t test. We found 54 fascicular constrictions, with many variations. However, they could all be categorised by our method. The repeatability among the independent authors was 96%. The age at the onset of palsy was significantly younger in rotation-bulging than in rotation constriction (p = 0.0003). Our definition of describing fascicular constrictions was accurate, and should help to provide consensus in describing these palsies.

Recent Trends in Orthopedic Surgery Aiming to Improve Quality of Life for Those with Rheumatoid Arthritis: Data from a Large Observational Cohort

Objective. To describe current trends in the numbers of rheumatoid arthritis (RA)-related surgeries. Methods. The number of operations was determined for patients with RA in a large observational cohort [Institute of Rheumatology, Rheumatoid Arthritis (IORRA)] enrolled from 2001 to 2012. Results. The total number of operations peaked in 2002 and gradually decreased thereafter, but began to increase again in 2008. The number of total knee replacements has decreased since 2003, while the number of wrist and foot arthroplasties and the number of artificial finger prosthesis surgeries have increased gradually. Conclusion. Our results suggest that the number of orthopedic surgeries may change in response to changes in the drug therapy for RA.

Ulnar nerve strain at the elbow in patients with cubital tunnel syndrome: effect of simple decompression

Simple decompression of the ulnar nerve at the elbow has not been shown to reduce nerve strain in cadavers. In this study, ulnar nerve strain at the elbow was measured intraoperatively in 11 patients with cubital tunnel syndrome, before and after simple decompression. Statistical analysis was performed using a paired Student’s t-test. Mean ulnar nerve strain before and after simple decompression was 30.5% (range 9% to 69%) and 5.5% (range −2% to 11%), respectively; this difference was statistically significant (p < 0.01) with a statistical power of 96%. Simple decompression reduced ulnar nerve strain in all patients by an average of 24.5%. Our results suggest that the pathophysiology of cubital tunnel syndrome may be multifactorial, being neither a simple compression neuropathy nor a simple traction neuropathy, and simple decompression may be a favourable surgical procedure for cubital tunnel syndrome in terms of decompression and reduction of strain in the ulnar nerve.

Risk factors for established vertebral fractures in Japanese patients with rheumatoid arthritis: Results from a large prospective observational cohort study.

Abstract Objective. The aim of this study was to evaluate the associations between potential risk factors and the occurrence of established vertebral fractures in Japanese patients with rheumatoid arthritis (RA). Methods. A total of 10,469 patients with RA were enrolled in a prospective, observational study from 2000 to 2011. Self-reported vertebral fractures were verified using patients medical records and radiographs. Cox proportional hazards models were used to analyze independent contributions of various risk factors for established vertebral fracture occurrence. Results. During a mean follow-up of 5.8 years, established vertebral fractures in 170 patients were verified with medical records and radiographs. Multivariate Cox regression analyses estimated that the hazards ratios of sustaining vertebral fractures increased by 1.84 for female gender, 1.72 for every 10 years of increased age, 1.26 for Disease Activity Score in 28 joints (DAS28), 1.44 for Japanese Health Assessment Questionnaire-Disability Index (J-HAQ-DI), 2.21 for history of any previous fractures, and 1.09 for daily prednisolone dose (mg/day). Conclusion. We confirmed the associations between vertebral fractures and advanced age, J-HAQ-DI, and high daily prednisolone dose; and found significant correlations between vertebral fractures and female gender, DAS28, and history of any previous fracture in Japanese RA patients.

Shoulder internal rotation elbow flexion test for diagnosing cubital tunnel syndrome

BACKGROUND Shoulder internal rotation enhances symptom provocation attributed to cubital tunnel syndrome. We present a modified elbow flexion test--the shoulder internal rotation elbow flexion test--for diagnosing cubital tunnel syndrome. METHODS Fifty-five ulnar nerves in cubital tunnel syndrome patients and 123 ulnar nerves in controls were examined with 5 seconds each of elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests before and after treatment (surgery in 18; conservative in others). For the shoulder internal rotation elbow flexion test position, 90° abduction, maximum internal rotation, and 10° flexion of the shoulder were combined with the elbow flexion test position. The test was considered positive if any symptom for cubital tunnel syndrome developed <5 seconds. Influence of the shoulder internal rotation elbow flexion test was evaluated by nerve conduction studies in 10 cubital tunnel syndrome nerves and 7 control nerves. RESULTS The sensitivities/specificities of the 5-second elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests were 25%/100%, 58%/100%, and 87%/98%, respectively. Sensitivity differences between the shoulder internal rotation elbow flexion test and the other two tests were significant. Shoulder internal rotation elbow flexion test results and cubital tunnel syndrome symptoms were significantly correlated. Influence of the shoulder internal rotation elbow flexion test on the ulnar nerve was seen in 8 of 10 cubital tunnel syndrome nerves but not in controls. CONCLUSIONS The 5-second shoulder internal rotation elbow flexion test is specific, easy and quick provocative test for diagnosing cubital tunnel syndrome.

Comparison of Shoulder Internal Rotation Test With the Elbow Flexion Test in the Diagnosis of Cubital Tunnel Syndrome

PURPOSE To compare the shoulder internal rotation test-a new, provocative test-with the elbow flexion test in the diagnosis of cubital tunnel syndrome (CubTS). METHODS Twenty-five patients with CubTS were examined before and after surgery with 10 seconds each of the elbow flexion and shoulder internal rotation tests. Fifty-four asymptomatic individuals and 14 neuropathy patients with a diagnosis other than CubTS were also examined as control cases. For the shoulder internal rotation test, the patients upper extremity was kept at 90° abduction, maximum internal rotation, and 10° flexion at the shoulder, with 90° elbow flexion and neutral position of the forearm and wrist, with finger extension. Test results were considered positive if any slight symptom attributable to CubTS occurred within 10 seconds. Extraneural pressure inside the cubital tunnel was intraoperatively measured with the positions of both the elbow flexion and shoulder internal rotation tests, in 15 of the CubTS cases. Statistical analyses were performed using Students t-test with a confidence level of 95%. RESULTS The preoperative sensitivity in CubTS cases was 80% in the 10-second shoulder internal rotation test and 36% in the 10-second elbow flexion test, and these differences were significant. None of the control cases had positive results in either test. All the CubTS cases improved with surgery; after surgery, neither test provoked symptoms in any surgical patient. The extraneural pressure increased in both provocative positions with no significant difference. CONCLUSIONS Positive results for the 10-second shoulder internal rotation test were more sensitive than that for the elbow flexion test of the same duration and seemed specific to CubTS.

Association between the elbow flexion test and extraneural pressure inside the cubital tunnel

PURPOSE The elbow flexion test is a standard, provocative diagnostic test for cubital tunnel syndrome (CubTS). The purpose of this study was to investigate the association between the elbow flexion test and the degree of extraneural pressure in the cubital tunnel of CubTS patients. METHODS Extraneural pressure on the ulnar nerve in the cubital tunnel was evaluated using 0.7-mm thickness catheter during surgery of 25 CubTS cases and compared with the results of preoperative elbow flexion testing. Statistic analysis was performed using Students t-test with a confidence level of 95% (p < .05). RESULTS Forty-eight percent of the patients were positive for the elbow flexion test. Mean extraneural pressure was significantly higher in maximum elbow flexion than in maximum elbow extension (p < .001). No significant association was seen between the result of 45 seconds of the elbow flexion test and the extraneural pressure in the cubital tunnel induced by maximum elbow flexion (p = .45). CONCLUSIONS Our results suggested that the mechanism of provocation of symptoms of CubTS by the elbow flexion could not be explained simply by dynamic pressure in the cubital tunnel, and other pathophysiological factors could also be contributing. TYPE OF STUDY/LEVEL OF EVIDENCE Diagnostic III.