In Vivo Metacarpophalangeal Joint Kinematics After Silicone Implant Arthroplasty in Patients With Rheumatoid Arthritis.

PURPOSE: The aim of this study was to determine the potential mechanism of implant fracture using 3-dimensional motion analysis of patients with rheumatoid arthritis. METHODS: Active flexion motion in 9 hands (34 fingers) of 6 female patients with rheumatoid arthritis who previously underwent hinged silicone metacarpophalangeal joint arthroplasty was examined using 4-dimensional computed tomography. Positions of the proximal phalanges relative to the metacarpals were quantified using a surface registration method. The deformation of the silicone implant was classified in the sagittal plane in the maximum flexion frame. The longitudinal bone axis of the proximal phalanx and the helical axis of the proximal phalanx were evaluated in 3-dimensional coordinates based on the hinge of the silicone implant. RESULTS: Nineteen fingers were classified into group 1, in which the silicone implant moved volarly during flexion without buckling of the distal stem. Twelve fingers were classified into group 2, in which the distal stem of the silicone implant buckled. Three fingers were classified into group 3, in which the base of the distal stem had already fractured. Quantitatively, the longitudinal bone axes of the proximal phalanges were displaced from dorsal to volar in the middle stage of flexion and migrated in the proximal direction in the late phase of flexion. The helical axes of the proximal phalanges were located on the dorsal and proximal sides of the hinge, and these tended to move in the volar and proximal directions as the metacarpophalangeal joint flexed. CONCLUSIONS: Volar and proximal translation of the proximal phalange was observed on 4-dimensional computed tomography. CLINICAL RELEVANCE: Proximal displacement of the bone axis late in flexion appears to be a contributing factor inducing implant fractures, because the pistoning motion does not allow the implant to move in the proximal direction.

Risk Factors Contributing to Early Implant Fracture in Silicone Metacarpophalangeal Joint Arthroplasty for Patients With Rheumatoid Arthritis.

PURPOSE: To identify the risk factors associated with early implant fracture of silicone metacarpophalangeal (MCP) joint arthroplasty using the volar hinge silicone implant for patients with rheumatoid arthritis. METHODS: We retrospectively reviewed 113 fingers of 31 hands that underwent MCP joint arthroplasty between 2008 and 2014, with a minimum follow-up of 3 years,. An implant fracture within 3 years after surgery was regarded as an early implant fracture. Patient records were reviewed for potential risk factors of age, affected fingers, ulnar drift angle, and range of motion of the MCP joint before surgery and 1 year after surgery. Candidate risk factors were compared at the level of the digit and at the patient level. RESULTS: With fracture of the implants as the end point, Kaplan-Meier estimated survival rate was 74.3% at 3 years and 67.9% at 5 years. Early implant fracture was detected in 29 fingers. Bivariate analyses showed significant associations between early implant fracture and MCP joint arc of motion before surgery, MCP joint flexion range 1 year after surgery, and MCP joint arc of motion 1 year after surgery. Multiple logistic regression analysis showed that increased MCP joint flexion range 1 year after surgery was an independent risk factor for early implant fracture. CONCLUSIONS: Increasing MCP joint flexion range was associated with increased fractures of the implants. We propose that the MCP joint flexion range should be restricted to less than 60° in postoperative rehabilitation; it is necessary to educate the patient to permanently avoid excessive flexion of the MCP joint. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Anatomical features of the aortic root in aortic stenosis and a novel approach for transcatheter aortic valve implantation.

A narrow and calcified sinotubular junction (STJ) represents a risk for ascending aortic dissection after balloon-expandable transcatheter aortic valve implantation (TAVI). The aim of this study was to assess computed tomography (CT)-based aortic root morphology in patients with aortic stenosis (AS), and to evaluate the feasibility of a two-step inflation technique that we devised for TAVI using the SAPIEN 3 in patients with a narrow and calcified STJ. We retrospectively analyzed the STJ diameter (STJD) as well the as aortic annulus diameter (AAD) and STJ calcification using CT imaging in 412 patients undergoing TAVI. We defined a "narrow STJ" as a minimum STJD that was smaller than the diameter corresponding to a 10% oversized annulus area, and a "calcified STJ" as an STJ calcification angle > 90°. A "narrow and calcified STJ" was identified in 54 patients (13.1%) of patients. Among them, we performed TAVI using the two-step inflation technique with SAPIEN 3 in 20 patients and compared with 11 patients that underwent the conventional inflation procedure. Two-step inflation was successfully performed without ascending aortic dissection in all 20 patients. The effective orifice area index at discharge in these 20 patients was similar to that in 11 patients who underwent the conventional inflation procedure for a "narrow and calcified STJ" [1.40 (1.20-1.51) vs. 1.33 (1.18-1.41) cm2/m2, p = 0.23]. Although further assessment is required, the two-step inflation technique with the SAPIEN 3 is feasible for a narrow and calcified STJ.

Involvement of the K+-Cl- co-transporter KCC2 in the sensitization to morphine-induced hyperlocomotion under chronic treatment with zolpidem in the mesolimbic system.

Benzodiazepines are commonly used as sedatives, sleeping aids, and anti-anxiety drugs. However, chronic treatment with benzodiazepines is known to induce dependence, which is considered related to neuroplastic changes in the mesolimbic system. This study investigated the involvement of K(+) -Cl(-) co-transporter 2 (KCC2) in the sensitization to morphine-induced hyperlocomotion after chronic treatment with zolpidem [a selective agonist of γ-aminobutyric acid A-type receptor (GABAA R) α1 subunit]. In this study, chronic treatment with zolpidem enhanced morphine-induced hyperlocomotion, which is accompanied by the up-regulation of KCC2 in the limbic forebrain. We also found that chronic treatment with zolpidem induced the down-regulation of protein phosphatase-1 (PP-1) as well as the up-regulation of phosphorylated protein kinase C γ (pPKCγ). Furthermore, PP-1 directly associated with KCC2 and pPKCγ, whereas pPKCγ did not associate with KCC2. On the other hand, pre-treatment with furosemide (a KCC2 inhibitor) suppressed the enhancing effects of zolpidem on morphine-induced hyperlocomotion. These results suggest that the mesolimbic dopaminergic system could be amenable to neuroplastic change through a pPKCγ-PP-1-KCC2 pathway by chronic treatment with zolpidem.

Detection of left coronary ostial obstruction during transcatheter aortic valve replacement by coronary flow velocity measurement in the left main trunk by intraoperative transesophageal echocardiography.

BACKGROUND: Coronary obstruction is a rare but catastrophic complication of transcatheter aortic valve replacement (TAVR) and occurs mostly at the left coronary artery (LCA) ostium. However, some patients do not show any clinical findings, and thus, its detection is sometimes difficult. The peak diastolic flow velocity in left main coronary artery (LM) was reportedly increased in significant stenosis lesions. We evaluated the effectiveness of measuring blood flow velocities in LM by transesophageal echocardiography (TEE) for the detection of LCA ostial obstruction during a TAVR procedure. METHODS: A total of 1105 consecutive patients who underwent TAVR in Sendai Kousei Hospital between September 2014 and December 2020 were enrolled. The LM blood flow velocity was measured at pre- and post-valve implantation. RESULTS: Among the 1105 patients, 9 had LCA ostial obstruction. The peak LM blood flow velocity at post-TAVR [0.90 (0.39-1.15) vs. 0.37 (0.28-0.50) m/s; p = 0.0046) was significantly higher in 9 patients who had LCA ostial obstruction, compared with the remaining 1096 patients who had not (controls), although no significant difference was observed before the TAVR procedures between the two groups. The post- to pre-TAVR LM flow velocity ratio [2.26 (1.31-3.42) vs. 1.06 (0.82-1.36); p = 0.0030] was also significantly higher in patients with LCA obstruction, compared to the controls. Furthermore, the post- to pre-TAVR LM blood flow velocity ratio was >2.0 in all six hemodynamically stable patients with LCA obstruction, whereas <2.0 in all three patients with LCA obstruction who showed hemodynamic collapse at post-TAVR procedure. CONCLUSION: Coronary blood flow velocity in LM significantly increased in hemodynamically stable LCA obstruction patients. The intraprocedural TEE measurement of the LM flow velocities would be potentially useful to detect asymptomatic and hemodynamically stable LCA ostial obstruction.

En face view of the transcatheter heart valve from deep right-anterior-oblique cranial position for coronary access after transcatheter aortic valve implantation: a case series.

BACKGROUND: Coronary access after transcatheter aortic valve implantation (TAVI) is challenging due to the changes in aortic geometry. The perpendicular (long-axis) view of the transcatheter heart valve (THV) is usually used as the primary fluoroscopic angle. However, it does not always provide sufficient information on the rotational axis needed for selective coronary ostia engagement. The en face (short-axis) view from the deep right-anterior-oblique cranial position gives us additional information about three-dimensional spatial relationship of the THV and coronary ostia. CASE SUMMARY: We present three cases of coronary access after TAVI. We were successful in the use of the 'en face' view along with the perpendicular view in these cases. DISCUSSION: The use of the en face view complements that of the perpendicular long-axis view since it allows the understanding of the three-dimensional spatial relationship of the THV and the coronary ostia during fluoroscopy and control of catheter manipulation in two directions (up/down for perpendicular and clockwise/counterclockwise for en face view). We believe that the en face view helps improve the technical success of coronary access after TAVI.

Three-dimensional alignment of the upper extremity in the standing neutral position in healthy subjects.

BACKGROUND: Though alignment of the spine and lower extremities in the standing neutral position has been evaluated, a few studies evaluating the alignment of the upper extremities have also been made. This study assessed the normal alignment of the upper extremities in the standing neutral position and clarified the three-dimensional angular rotations of the upper extremity joints. METHODS: Computed tomography (CT) images of 158 upper extremities from 79 healthy volunteers were prospectively acquired in the standing neutral position using an upright CT scanner. Three-dimensional coordinate systems of the thorax, scapula, humerus, and forearm were designated, and three-dimensional angular rotations of the scapulothoracic, glenohumeral, and elbow joints were calculated. RESULTS: The median angle of the scapulothoracic joint was 9.2° (interquartile range [IQR], 5.2°-12.5°) of upward rotation, 29.0° (IQR, 24.9°-33.3°) of internal rotation, and 7.9° (IQR, 4.3°-11.8°) of anterior tilt. The median angle of the glenohumeral joint was 4.5° (IQR, 0.9°-7.8°) of abduction, 9.0° (IQR, 2.2°-19.0°) of internal rotation, and 0.3° (IQR, - 2.6°-3.1°) of extension. The median angle of the elbow joint was 9.8° (IQR, 6.9°-12.4°) of valgus, 90.2° (IQR, 79.6°-99.4°) of pronation, and 15.5° (IQR, 13.2°-18.1°) of flexion. Correlations in angular rotation values were found between the right and left upper extremities and between joints. CONCLUSIONS: This study clarified the three-dimensional angular rotation of upper extremity joints in the standing neutral position using an upright CT scanner. Our results may provide important insights for the functional evaluation of upper extremity alignment.

Delivery balloon volume positively correlates with the diameter and effective orifice area of implanted SAPIEN 3.

BACKGROUND: In transcatheter aortic valve replacement (TAVR) using SAPIEN 3 (S3) (Edwards Lifesciences, Irvine, CA, USA), some clinicians decrease or increase the delivery balloon volume (VOL) when deploying S3 or conducting post-dilatation. However, the effects of controlling VOL on transcatheter heart valve diameter (THVD) and valve function remain unclear. We assessed associations among VOL, THVD, and effective orifice area (EOA) of S3. METHODS: We enrolled patients undergoing TAVR using 23- and 26-mm S3 in Sendai Kousei Hospital between 2017 and 2019. VOL was controlled based on preprocedural computed tomography and intraprocedural transesophageal echocardiography (TEE). THVD were defined as the diameters of transcatheter heart valve at mid-level measured by TEE. RESULTS: In enrolled 332 patients (23-mm, n = 188; 26-mm, n = 144), one (0.3%) and two (0.6%) developed annulus rupture and moderate/severe paravalvular leak, respectively. VOL at deployment was positively correlated with THVD on deployment (23-mm, r = 0.44, p < 0.001; 26-mm, r = 0.57, p < 0.001) and EOA (23-mm, r = 0.23, p = 0.0019; 26-mm, r = 0.22, p = 0.0094). In multiple regression analyses, VOL and post-dilatation were significant determinants of THVD, although aortic annulus area, calcium volume, and pre-dilatation were not. The areas under the receiver operating characteristic curve that were used to evaluate the accuracy of the index obtained by dividing THVD by body surface area (indexed THVD) to predict patient-prosthesis mismatch (PPM) were 0.744 and 0.811 in the 23- and 26-mm cohorts, respectively. A cut-off indexed THVD of ≤11.5 and 12.1 mm/m2 well predicted PPM (23-mm, odds ratio, 5.20; 95% confidence interval, 1.33-20.3; 26-mm, odds ratio 14.1, 95% confidence interval 2.40-81.0). CONCLUSION: VOL was positively correlated with THVD and EOA. Smaller indexed THVD was associated with a higher incidence of PPM. Controlling VOL under on-site THVD evaluation may be useful in reducing the PPM incidence.

Quantitative analysis of metacarpophalangeal joints during active flexion using four-dimensional computed tomography.

BACKGROUND: The metacarpophalangeal joint has a unique morphology with a high degree of freedom. However, few studies have analyzed the kinematics of fingers owing to the rapid movement of the small bones involved. The in-vivo kinematics of metacarpophalangeal joints were analyzed by four-dimensional computed tomography (4DCT) and associated with its morphology. METHODS: The flexion motion of the fingers of bilateral hands in 10 volunteers were examined using 4DCT. Iterative surfaces were registered to trace the surface of the proximal phalanges with respect to metacarpals. Rotation angles were calculated using Euler/Cardan angles. FINDINGS: In the index finger, the proximal phalange supinated to a maximum flexion of 40° and then pronated, and its range of rotation was larger than the previous reports. In the other fingers, the proximal phalanges continued to supinate during flexion. The helical axis of the proximal phalange passed a point extremely close to the center point of bilateral condyles, and it moved toward the proximal and palmar directions until the middle stage of flexion and toward the proximal and dorsal directions during the late stage of flexion. The translation of the rotation axis was larger in the ring and little fingers. INTERPRETATION: The rotation in the index finger was larger than previously reported. The helical axes moved in the dorsal direction and proximally during the latter phase of the flexion. These results can be employed to better understand the causes of implant failure of the metacarpophalangeal joints.

Nationwide Distribution of Bovine Influenza D Virus Infection in Japan.

Cattle are major reservoirs of the provisionally named influenza D virus, which is potentially involved in the bovine respiratory disease complex. Here, we conducted a serological survey for the influenza D virus in Japan, using archived bovine serum samples collected during 2010-2016 from several herds of apparently healthy cattle in various regions of the country. We found sero-positive cattle across all years and in all the prefectural regions tested, with a total positivity rate of 30.5%, although the positivity rates varied among regions (13.5-50.0%). There was no significant difference in positivity rates for Holstein and Japanese Black cattle. Positivity rates tended to increase with cattle age. The herds were clearly divided into two groups: those with a high positive rate and those with a low (or no) positive rate, indicating that horizontal transmission of the virus occurs readily within a herd. These data demonstrate that bovine influenza D viruses have been in circulation for at least 5 years countrywide, emphasizing its ubiquitous distribution in the cattle population of Japan.

Implication of mGlu5 receptor in the enhancement of morphine-induced hyperlocomotion under chronic treatment with zolpidem.

Long-term exposure to zolpidem induces drug dependence, and it is well known that the balance between the GABAergic and glutamatergic systems plays a critical role in maintaining the neuronal network. In the present study, we investigated the interaction between GABAA receptor α1 subunit and mGlu5 receptor in the limbic forebrain including the N.Acc. after treatment with zolpidem for 7 days. mGlu5 receptor protein levels were significantly increased after treatment with zolpidem for 7 days, and this change was accompanied by the up-regulation of phospholipase Cß1 and calcium/calmodulin-dependent protein kinase IIα, which are downstream of mGlu5 receptor in the limbic forebrain. To confirm that mGlu5 receptor is directly involved in dopamine-related behavior in mice following chronic treatment with zolpidem, we measured morphine-induced hyperlocomotion after chronic treatment with zolpidem in the presence or absence of an mGlu5 receptor antagonist. Although chronic treatment with zolpidem significantly enhanced morphine-induced hyperlocomotion, this enhancement of morphine-induced hyperlocomotion was suppressed by treating it with the mGlu5 receptor antagonist MPEP. These results suggest that chronic treatment with zolpidem caused neural plasticity in response to activation of the mesolimbic dopaminergic system accompanied by an increase in mGlu5 receptor.