Current status and future prospects of the Japanese orthopaedic association national registry (JOANR), Japan's first national registry of orthopaedic surgery.

The Japanese Orthopaedic Association National Registry (JOANR) is Japan's first national registry of orthopaedic surgery, which has been developed after having been selected for the Project for Developing a Database of Clinical Outcome approved by the Health Policy Bureau of the Ministry of Health, Labour and Welfare. Its architecture has two levels of registration, one being the basic items of surgical procedure, disease, information on surgeons, surgery-related information, and outcome, and the other being detailed items in the affiliated registries of partner medical associations. It has a number of features, including the facts that, because it handles medical data, which constitute special care-required personal information, data processing is conducted entirely in a cloud environment with the imposition of high-level data security measures; registration of the implant data required to assess implant performance has been automated via a bar code reader app; and the system structure enables flexible collaboration with the registries of partner associations. JOANR registration is a requirement for accreditation as a core institution or partner institution under the board certification system, and the total number of cases registered during the first year of operation (2020) was 899,421 registered by 2,247 institutions, providing real-world evidence concerning orthopaedic surgery.

Further investigation of the rapid-onset and short-duration action of the G protein-biased µ-ligand oliceridine.

TRV130 (oliceridine), a G protein-biased ligand for µ-opioid receptor, has recently been synthesized. It is considered to have strong antinociceptive effects and only minor adverse effects. However, whether or not oliceridine actually exhibits an ideal pharmacological profile as an analgesic has not yet been fully clarified in animal studies. This study examined the pharmacological profile of oliceridine in cells and animals. Oliceridine (10 µM) did not produce any µ-opioid receptor internalization in cells even though it increased impedance, which reflects the activation of Gi protein using the CellKey™ system, and inhibited the formation of cAMP. In mice, oliceridine (0.3-10 mg/kg) produced a dose-dependent antinociceptive effect with a rapid-onset and short-duration action in the hot-plate test, as well as antihyperalgesia after sciatic nerve ligation without the development of antinociceptive tolerance using the thermal hyperalgesia test. On the other hand, oliceridine inhibited gastrointestinal transit. Furthermore, oliceridine produced rapid-onset hyperlocomotion at antinociceptive doses; sensitization developed in mice and an emetic effect was observed in ferrets. These results indicate that, although oliceridine may produce dopamine-related behaviors even through selective stimulation of the G-protein-biased µ-opioid receptor pathway, it still offers advantages for breakthrough pain without antinociceptive tolerance with adequate doses.

Synergistic effects of MDMA and ethanol on behavior: Possible effects of ethanol on dopamine D2 -receptor-related signaling.

Polydrug abuse is common among drug abusers. In particular, psychostimulants are often taken with ethanol, and the combination of 3,4-methylenedioxymethamphetamine (MDMA) and alcohol is one of the most common forms of polydrug abuse. However, the mechanism by which these drugs influence behavior remains unclear. The present study was designed to delineate the mechanisms that underlie the effects of the interaction between MDMA and ethanol on behavior in rodents. The combination of MDMA with ethanol enhanced their locomotor-increasing, rewarding, and discriminative stimulus effects without enhancing their effects on the release of dopamine from the nucleus accumbens in rodents. In addition, ethanol potently enhanced locomotor activity produced by the dopamine receptor agonist apomorphine in mice. In antagonism tests, the dopamine D1 -receptor antagonist SCH23390, but not the D2 -receptor antagonist haloperidol, completely suppressed hyperlocomotion induced by MDMA. However, hyperlocomotion induced by the co-administration of MDMA and ethanol was potently suppressed by haloperidol. These results suggest that the synergistic effects of MDMA and ethanol are mediated through dopamine transmission, especially through postsynaptical regulation of D2 -receptor-mediated functions.

Outcomes of conservative treatment for bony mallet fingers.

BACKGROUND: The treatment strategy for bony mallet fingers remains controversial. The outcomes of conservative treatment were investigated in this study. In addition, the time to bone union, and gap between the bone fragment and distal phalanx are discussed. METHODS: The subjects were 26 patients (27 fingers) with bony mallet fingers (20 males and 6 females, mean age: 46.0 years old, the mean limitation of extension of the distal interphalangeal (DIP) joint: - 20.2°). In conservative treatment, splinting was applied for 6 weeks, followed by 2-week taping. The time to bone union, range of motion of the DIP joint, and the Crawford classification on the final follow-up were investigated. In addition, the bone fragment occupation rate was evaluated on plain radiography on the first examination. Furthermore, the gap on the first examination and after splinting. The relationship between the gap and bone union period was also investigated. RESULTS: The mean time from injury to bone union was 170.2 days, the mean range of motion of the DIP joint was - 8.5° in extension and 60.9° in flexion, and the Crawford classification was Excellent for 22 fingers, Good for 2, Fair for 2, and Poor for 1. On the first examination, the mean bone fragment occupation rate was 44.0%. The mean gap on the first examination was 1.1 mm and this was significantly narrowed to 0.8 mm after splinting (p < 0.01). No significant correlation was noted between the time to bone union and gap on the first examination (p = 0.16), however, a significant positive correlation was noted between them after splinting (p < 0.01). CONCLUSIONS: This study suggested that a favorable clinical outcome can be achieved by conservative treatment. Moreover, the bone union period decreased as the gap after splinting decreased, being significantly correlated.

Anatomical-positional relationship between the bone structure of the distal radius and flexor pollicis longus tendon using ultrasonography.

PURPOSE: In this study, using an ultrasonography, we investigated the positional relationship between the volar bone cortex of distal radius and flexor pollicis longus (FPL) tendon in the distal radius of healthy subjects. METHODS: The subjects were 32 healthy volunteers (56 wrists) (Age 32.9 ± 8.5, 16 males and 16 females). Their wrists were imaged by an ultrasonography. The distances between the watershed line (WS) and FPL (A), between the distal margin of pronator quadratus (DMPQ) and FPL (B), between the FPL and volar radial bone cortex at the maximum muscle belly of the PQ muscle right below the sliding region of the FPL tendon (C), and between the WS and DMPQ (D) were measured. RESULTS: All these parameters showed a normal distribution. When the correlation among the parameters was investigated, a correlation with an index of the physique, BMI, was noted in A (P < 0.01), B (P < 0.01), and C (P < 0.01), but no correlation was noted only in D (P = 0.59). CONCLUSIONS: Our results were suggested that when distal radius fracture is treated with a distal plate placement, the appropriate placement can be achieved by applying about 3 mm additional dissection of soft tissue on the volar bone cortex distal to the DMPQ.

Evaluation of the pulley function of the hamulus of the hamate for the flexor tendons.

PURPOSE: The aim of this study was to measure the curvature radii of the finger flexor tendons on CT acquired using tendon conditions to examine whether the hamulus of the hamate functions as a pulley of the flexor tendon. METHODS: The subjects were 20 healthy volunteers (40 hands) (14 males and 6 females, mean age: 27.5 years old). Their hands were imaged in extension and flexion of the fingers on CT. The curvature radii of the little and middle finger flexor tendons at the hamulus of the hamate were calculated. RESULTS: The curvature radii of the little and middle finger flexor tendons were 24.8 ± 7.3 and 327.1 ± 343.9 mm in finger extension, respectively, and 21.3 ± 5.3 and 265.1 ± 202.9 mm in finger flexion, respectively. The curvature radius of the little finger flexor tendon was significantly smaller than that of the middle finger flexor tendon in both finger extension and flexion (P < 0.01). CONCLUSIONS: Our study suggested that the hamulus of the hamate functions as a pulley for the little finger flexor tendon.

Preoperative timed single leg standing time is associated with the postoperative activity of daily living in aged disabled patients with end-stage knee osteoarthritis at six-months after undergoing total knee arthroplasty.

OBJECTIVES: The aim of the present study was to investigate the effect size (ES) of total knee arthroplasty (TKA) for the symptoms and lower limb function and identify preoperative factor(s) associated with the post-operative activity of daily living (ADL) in aged patients with end-stage knee OA undergoing TKA. METHODS: Fifty-nine aged patients with end-stage knee OA (mean age: 74.6 years) were enrolled in this study. The symptoms and lower limb function of the patients were evaluated using the Japanese Knee Osteoarthritis Measure (JKOM), the timed up and go (TUG) test and timed single-legged stance test with eyes open (TSLS) before and after six months from the operation. RESULTS: While the ES of TKA for the improvement of pain was 2.83, the ES of TKA for the improvement of ADL, TUG and TSLS were 1.30, 0.59, and 0.49, respectively. While the post-operative ADL score was not associated with the preoperative ADL or pain scores, it was associated with the preoperative TUG and TSLS scores. A multiple regression analysis revealed that the one preoperative factor associated with the postoperative ADL was the TSLS. CONCLUSION: The preoperative TSLS is associated with the postoperative ADL in aged disabled patients with end-stage knee OA.

Lumbar artery branches coursing vertically over the intervertebral discs of the lower lumbar spine: an anatomic study.

PURPOSE: Bleeding from the lumbar artery is a potential complication during the transpsoas approach to the lower lumbar intervertebral discs. In this anatomic study, the morphological relationships between the branches of the lumbar artery and the lower intervertebral disc were investigated to assess the risk of injury to the branches of the lumbar segmental arteries. METHODS: We studied 88 sites (86 lumbar arteries) at the third and fourth lumbar vertebrae bilaterally in 22 formalin-fixed cadavers. The branches of the lumbar artery coursing along the lateral sides of the lower intervertebral disc [muscular branch, anastomotic branch, and branch supplying the spinal nerve and plexus (BSNP)] and the iliolumbar artery running upward over the L4-5 disc were identified. Branches crossing the intervertebral discs vertically were evaluated. RESULTS: Muscular branches with a lumen structure longer than 2 cm coursed vertically over the middle third of the intervertebral disc in 3 of 88 sites (3.4 %). Anastomotic branches ran downward in 13 of 88 (14.8 %), and iliolumbar arteries ran upward on the posterior third of the lateral sides of the disc in 2 of 88 (2.3 %). BSNPs ran downward through the posterior third of the disc at 18 of 88 sites (20.5 %). Overall, the arterial branches coursed vertically over the posterior third of the lateral sides of the intervertebral discs in approximately 30 % of subjects. CONCLUSIONS: Lumbar artery branches coursed vertically over the middle third and the posterior third of the lateral sides of the intervertebral discs in approximately 3 and 30 % of subjects, respectively.

Establishment of opioid-induced rewarding effects under oxaliplatin- and Paclitaxel-induced neuropathy in rats.

The rewarding effects of µ-receptor agonists can be suppressed under several pain conditions. We recently showed that clinically used µ-receptor agonists possess efficacies for relieving the neuropathic pain induced by chemotherapeutic drug in rats; however, it is possible that the use of µ-receptor agonists may trigger the rewarding effects even under chemotherapeutic drug-induced neuropathic pain. Nevertheless, no information is available regarding whether µ-receptor agonists produce psychological dependence under chemotherapeutic drug-induced neuropathic pain. Therefore, we examined the effects of neuropathy induced by chemotherapeutic drugs on the rewarding effects of morphine, oxycodone, and fentanyl in rats. Repeated treatment with oxaliplatin or paclitaxel produced neuropathy as measured by the von Frey test. Rewarding effects produced by antinociceptive doses of µ-receptor agonists were not suppressed under oxaliplatin- or paclitaxel-induced neuropathy. Furthermore, the morphine-induced increase in the release of dopamine from the nucleus accumbens, which is a critical step in the rewarding effects of µ-receptor agonists, was not altered in paclitaxel-treated rats. These results suggest that the rewarding effects of µ-receptor agonists can still be established under oxaliplatin- or paclitaxel-induced neuropathic pain. Therefore, patients should be carefully monitored for psychological dependence on µ-receptor agonists when they are used to control chemotherapeutic drug-induced neuropathic pain.

Correlation of the total superoxide dismutase activity between joint fluid and synovium in end-stage knee osteoarthritis.

Recently, we found significantly reduced total superoxide dismutase (SOD) activity in the cartilage of patients with end-stage knee osteoarthritis (OA). In this study, we aimed to evaluate the SOD activity in serum, joint fluid, cartilage, and synovial membrane samples collected from 52 patients with end-stage knee OA who underwent total knee arthroplasty. The relationship between the total SOD activity in each tissue was evaluated using Spearman's rank correlation coefficient. The joint fluid total SOD activity was used as the objective variable, and its association with the serum, cartilage, and synovial total SOD activities was evaluated using multiple linear regression analysis. Univariate analysis revealed that joint fluid total SOD activity was positively correlated with synovial total SOD activity. Multiple linear regression analysis using joint fluid total SOD activity as the objective variable showed a positive association with synovial total SOD activity (ß = 0.493, adjusted R2 = 0.172, P < 0.01). In patients with end-stage knee OA, the state of the synovial total SOD activity is better reflected by the total SOD activity in the joint fluid than that in the cartilage. Joint fluid total SOD activity may serve as a biomarker for the treatment and prevention of synovitis.

Association between dietary variety status and sarcopenia as defined by the Asian Working Group for Sarcopenia 2019 consensus in older outpatients at a hospital specializing in geriatric medicine: A cross­sectional study with baseline data of prospective cohort study (JUSTICE­TOKYO study).

To the best of our knowledge, little is known about the association between dietary variety status and sarcopenia in university-affiliated geriatric hospital in elderly. The present study aimed to investigate, in a multidisciplinary setting, the prevalence of sarcopenia and association between dietary variety status and sarcopenia in older outpatients at Juntendo Tokyo Koto Geriatric Medical Center (Tokyo, Japan). Between October 2020 and December 2021, a cross-sectional study of outpatients aged ≥65 years [458 male (44%) and 584 female (56%); mean age, 78.2±6.1 years] was conducted to assess prevalence of sarcopenia, according to Asian Working Group for Sarcopenia 2019 criteria, and the relationship between dietary variety status and sarcopenia. Patient profile, comorbidities, drug use, neuropsychological data, abdominal symptoms, pulmonary function and dietary variety status were collected. Of 1,042 subjects, there were 223 (21.4%) with [142 male (63.7%) and 81 female (36.3%); mean age, 80.6±6.3 years] and 819 (78.6%) without sarcopenia [316 male (38.6%) and 503 female (61.4%); mean age, 77.6±5.8]. In multivariate analysis, older age, male sex, low body mass index, high Brinkman Index and phase angle, low quality of life, history of daycare use, diabetes mellitus, osteoporosis and low Mini-Mental State Examination and Dietary Variety Score were related to sarcopenia. The prevalence of sarcopenia was higher in than in community-dwelling individuals. Dietary variety status was associated with sarcopenia.

Clinical Efficacy of Melon GliSODin® for the Treatment of Aging-Related Dysfunction in Motor Organs-A Double Blind, Randomized Placebo-Controlled Study.

BACKGROUND: Locomotive syndrome is a concept proposed in Japan involving decreased mobility due to osteoarthritis, osteoporosis, and sarcopenia. This double-blind, randomized study aimed to investigate the effects of superoxide dismutase (SOD)-rich melon extract (Melon GliSODin®) on locomotive syndrome. METHODS: For 6 months, we administered oral Melon GliSODin® (500.4 mg/day) or a placebo to 24 and 22 women, respectively (aged 50-80 years), with knee or lower back discomfort or pain. Using baseline and 6-month data, changes in the Verbal Rating Scale and in subjective symptoms (determined using the Japanese Knee Osteoarthritis Measure, Locomo 25, the Roland-Morris Disability questionnaire, and the Chalder Fatigue Scale) were assessed, along with various oxidative markers, antioxidants, inflammatory markers, renal and liver function biochemical markers, bone metabolism markers, body composition, and motor function. RESULTS: Oral Melon GliSODin® administration tended to be associated with a larger improvement in subjective symptom scores, a reduction in oxidative markers (malondialdehyde and diacron reactive oxygen metabolites) and tumor necrosis factor-α, and a significant increase in non-fat mass between baseline and 6 months. However, no statistically significant differences were observed between the groups for outcomes at 6 months. CONCLUSIONS: Melon GliSODin® tended to improve the subjective symptoms of participants who had knee or lower back pain or discomfort. Melon GliSODin® administration may help to prevent the progression of locomotive syndrome. Future studies involving larger sample sizes and more stringent randomization protocols are needed to determine differences between the placebo and Melon GliSODin® groups.

Influence of Smoking in the Clinical Outcomes of Distal Radius Fractures.

Introduction There are various studies that reviewed the effect of cigarette smoking in fracture healing process. Nonunion, delayed union, and residual pain are the significant risk factors associated with smoking and fracture healing. Little has been known about the impact of smoking in distal radius fracture healing. We intend to explore in brief the effect of smoking in distal radius fracture healing and comparing it with nonsmokers having the same fracture fixation and analyze the outcomes with respect to fracture healing and return of function. Materials and Methods Of the total 186 patients, 92 were included in the study with ( n = male: 31, female: 61) mean age of 60.2 years. They were divided into two groups: smoking ( n = 43) and nonsmoking ( n = 49). All had surgical fixation of the distal radius with volar locking plate and started on early mobilization. The range of motion of the wrist, grip, visual analog scale, quick disabilities of the arm and shoulder and hand score, Mayo wrist score, and bone healing period were noted between these two groups and compared with statistical analysis. Results The mean follow-up period was 8.7 months. There was a significant association of young age and male patients having distal radius fractures in the smoking group ( p < 0.05). All fractures healed well in both groups without complications. There was no significant difference between these two groups in terms of range of motion, grasp, bone healing period, and functional outcomes. Conclusion Despite the well-known fact that, smoking has negative implications in the fracture healing process, we found group of patients (smoking and nonsmoking) with distal radius fractures treated by volar locking plates healed well with good radiological union and excellent functional outcome There is no significant influence of smoking in distal radius fracture fixation.

Correction of humpback and DISI deformities by vascularized bone grafting in patients with scaphoid nonunion.

INTRODUCTION: Although vascularized bone grafting (VBG) using 1, 2 intercompartmental supraretinacular artery (1, 2 ICSRA) is effective for scaphoid nonunion, dorsal intercalated segment instability (DISI) deformity persists even after correction of humpback deformity (HD). The purpose of this retrospective study was to evaluate the correction of HD and DISI deformity after 1, 2 ICSRA VBG for scaphoid nonunion. METHODS: We treated 18 patients (mean age: 25.8, 16 males and 2 females) with scaphoid nonunion using a 1, 2-ICSRA VBG between January 2010 and December 2018. The average time from injury to surgery was 20.0 (3-120) months. The nonunions were located at the waist in all patients. The correction of HD and DISI deformity was investigated on the preoperative images and images at the last examination. RESULTS: In all patients, the correction of HD was positively correlated with that of DISI deformity. Moreover, we focused on the time from injury to surgery and evaluated changes in HD and DISI deformity according to the time to surgery. As a result, changes in HD and DISI deformity were positively correlated in patients with a shorter time to surgery but were not correlated when the time to surgery exceeded 5 months. CONCLUSIONS: These results suggest that DISI deformity can be corrected by correcting HD when the time from injury to surgery is short, but that correction is difficult if the time to surgery is prolonged.

Enhancement of the rewarding effects of 3,4-methylenedioxymethamphetamine in orexin knockout mice.

Orexinergic neurons, which are closely associated with narcolepsy, regulate arousal and reward circuits through the activation of monoaminergic neurons. Psychostimulants as well as 5-HT-related compounds have potential in the treatment of human narcolepsy. Previous studies have demonstrated that orexin receptor antagonists as well as orexin deficiencies affect the pharmacological effects of psychostimulants. However, little information is available on the consequences of psychostimulant use under orexin deficiency. Therefore, the present study was designed to investigate the abuse liability of psychostimulants in orexin knockout (KO) mice. In the present study, conditioned place preferences induced by methamphetamine and methylphenidate were not altered in orexin KO mice. Interestingly, we found that MDMA induced a conditioned place preference in orexin KO mice, but not in wild type (WT) mice. In addition, MDMA produced methylphenidate/methamphetamine-like discriminative stimulus effects in orexin KO mice, but not WT mice. Increases in 5-HT and dopamine release in the nucleus accumbens induced by MDMA were not altered by knockout of orexin; the steady-state level of G protein activation was higher in the limbic forebrain of orexin KO mice. In substitution tests using a drug discrimination procedure, substitution of 5-HT1A receptor agonist for the discriminative stimulus effects of methylphenidate was enhanced in orexin KO mice. These findings indicate that the orexinergic system is involved the rewarding effects of psychostimulants. However, there is a risk of establishing rewarding effects of psychostimulants even under orexin deficiency. On the other hand, deficiencies in orexin may enhance the abuse liability of MDMA by changing a postsynaptic signal transduction accompanied by changes in discriminative stimulus effects themselves.

A Survey of the Median Nerve Elasticity after Volar Locking Plate Fixation Using Ultrasound Elastography.

Introduction Median nerve disorder is one of the complications after surgery using volar locking plate (VLP) for distal radius fracture (DRF). In this study, elasticity of the median nerve was quantified using ultrasound elastography (EG) (real-time tissue EG) and compared between the operation and healthy sides in patients after surgery for DRF using VLP. Materials and Methods The subjects of this study were 28 patients (4 males and 24 females; mean age: 58.5 years) who could be followed up for more than 6 months after surgery for DRF and were able to be examined by EG. We evaluated median nerve elasticities on the operation and healthy sides using EG on the final follow-up. Results The median nerve strain ratios were 3.97 ± 2.99 on the operation side and 3.91 ± 1.51 on the healthy side, showing no significant difference in elasticity of the median nerve between the operation and healthy sides. Conclusion Median nerve disorder, which is a complication after surgery with VLP, can be objectively detected using EG capable of evaluating median nerve elasticity externally to detect medial nerve degeneration while degeneration of the median nerve. Thus, EG may be used as a useful diagnostic tool to prevent complications and decide on appropriate timing of VLP extraction.

Clinical Outcomes in Distal Radius Fractures Accompanied by Volar Lunate Facet Fragments: A Comparison between Dorsal and Volar Displaced Fractures.

Background: The treatment strategy for distal radius fractures accompanied by volar lunate facet fragment is controversial. In most cases, only the bone fragment size was discussed and a plate for distal placement is selected due to the accompanying volar lunate facet fragment regardless of the direction of bone fragment displacement. In this study, we divided distal radius fractures accompanied by volar lunate facet fragment into dorsal and volar displaced fractures, and treated these surgically based on different treatment strategies. Methods: The subjects were 25 patients with distal radius fractures accompanied by volar lunate facet fragment treated by reduction and fixation using a volar locking plate (VLP) (male: 14, female: 11, mean age: 57.8 years old). A proximal VLP (PVLP) was selected for 13 dorsal displaced fractures and a distal VLP (DVLP) was selected for 12 volar displaced fractures. The range of motion, VAS, Q-DASH, and Mayo score were evaluated at 12 months after surgery, and compared. Results: No significant difference due to the difference in the direction of displacement was noted in the range of motion, VAS, Q-DASH, or Mayo score at 12 months after surgery and there were no perioperative complications. In addition, no re-displacement of volar lunate facet fragment was noted after surgery in any patient and bone fusion was observed. Conclusions: Reduction and fixation with a PVLP are possible even for dorsal displaced distal radius fractures accompanied by volar lunate facet fragment. For the volar displaced distal radius fractures, a favorable postoperative outcome is possible by applying a DVLP to the distal ulnar.