Radial Collateral Ligament Laxity of Thumb Metacarpophalangeal Joint Following Trapeziometacarpal Arthrodesis.

PURPOSE: Trapeziometacarpal (TM) arthrodesis may increase adduction motion of the thumb metacarpophalangeal (MCP) joint, causing radial collateral ligament laxity. Stability of the MCP joint is important to the long-term functional outcome after TM arthrodesis. This study assessed preoperative and postoperative radial collateral ligament laxity using dynamic radiographs to confirm whether laxity was exacerbated after surgery and examined whether there is a relationship between the fixation angle of arthrodesis and the degree of laxity. METHODS: Forty-four thumbs in 33 patients who underwent TM arthrodesis and were followed for at least 5 years were studied. Dynamic radiographs in radial adduction-abduction and palmar adduction-abduction were obtained. We defined the midpoint of arc of motion as the fixation angle of arthrodesis in the radial and palmar planes. We measured the intersection angle between longitudinal axis of the first metacarpal (M1) and that of thumb proximal phalanx (P1). P1M1 angle in a palmar adduction view of dynamic radiographs reflected radial collateral ligament laxity in palmar adduction (adduction P1M1 angle). We subtracted a preoperative adduction P1M1 angle from a postoperative adduction P1M1 angle and defined its value as an exacerbated adduction P1M1 angle. RESULTS: Adduction P1M1 angle increased from 9° ± 5° to 18° ± 10°. The median exacerbated adduction P1M1 angle was 7°. Ten thumbs (23%) developed ulnar subluxation of MCP joint in the palmar adduction view of dynamic radiographs. Among them, two thumbs developed osteoarthritis of MCP joint (5%). Fixation angle of the arthrodesis was a mean of 35° ± 7° and 32° ± 9° in the radial arc and palmar arc planes, respectively. There was a positive correlation between increasing adduction P1M1 angle and TM arthrodesis in an increasingly palmarly abducted position. CONCLUSIONS: Radial collateral ligament laxity of thumb MCP joint was exacerbated after TM arthrodesis. Greater fixation angle in palmar abduction resulted in more laxity of the joint. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Functioning Free Muscle Transplantation to Restore Finger Movement for Sequalae of Volkmann Ischemic Contracture.

Volkmann ischemic contracture (VIC) is a devastating condition that results from neglected compartment syndrome, which leads to prolonged ischemia, irreversible tissue necrosis, and various degrees of muscle and nerve damage, causing serious motor and sensory functional implications for the limb and a spectrum of diseases associated with worsening deformities. A thorough understanding of the anatomy and VIC pathophysiology is needed to plan an appropriate strategy. Functioning free muscle transplantation (FFMT) can restore finger movement in a paralyzed limb but requires a three-staged approach to maximize the benefits of FFMT, leading to meaningful finger extrinsic function.

Fingertip Replantation: Surgical Technique, Tips, and Tricks.

SUMMARY: Replantation of fingertip amputations restores the original tissue and is the ideal treatment to provide the best aesthetic and functional outcome. However, successful fingertip replantation is considered challenging because it requires supermicrosurgery techniques. This article provides a detailed surgical technique for fingertip replantation and the authors' preferences and recommendations. In the authors' experience, the most important factors for successful fingertip replantation are meticulous vascular dissection, reliable arterial repair, and venous anastomosis to avoid postoperative venous congestion. Proximal arterial dissection until pulsatile bleeding is encountered avoids the zone of vascular injury, and is particularly important in crush or avulsion amputations. Distal arterial dissection is performed until undamaged intima is identified. The authors believe anastomosis to the central artery is reliable even in a Tamai zone II amputation. When an arterial defect is present, the authors recommend using a vein graft to anastomose to the central artery. In addition, the authors highly recommend at least one venous anastomosis to avoid postoperative venous congestion. In Tamai zone I, available veins can be found on the palmar side of the pulp. It is important to search directly below the dermis and remove adipose tissue around the vessels to secure space for anastomosis. The authors consider nerve suture in Tamai zone I and II replantations inessential, because spontaneous sensory recovery can be expected. Postoperative management of venous congestion, spasm in artery, and arterial thrombosis are as important as surgery.

Self-Consistent Picture of the Mass Ejection from a One Second Long Binary Neutron Star Merger Leaving a Short-Lived Remnant in a General-Relativistic Neutrino-Radiation Magnetohydrodynamic Simulation.

We perform a general-relativistic neutrino-radiation magnetohydrodynamic simulation of a one second-long binary neutron star merger on the Japanese supercomputer Fugaku using about 85 million CPU hours with 20 736 CPUs. We consider an asymmetric binary neutron star merger with masses of 1.2M_{⊙} and 1.5M_{⊙} and a "soft" equation of state SFHo. It results in a short-lived remnant with the lifetime of ≈0.017 s, and subsequent massive torus formation with the mass of ≈0.05M_{⊙} after the remnant collapses to a black hole. For the first time, we find that after the dynamical mass ejection, which drives the fast tail and mildly relativistic components, the postmerger mass ejection from the massive torus takes place due to the magnetorotational instability-driven turbulent viscosity in a single simulation and the two ejecta components are seen in the distributions of the electron fraction and velocity with distinct features.

Management of bone loss in acute severe open tibial fractures: a retrospective study of twenty nine cases-a treatment strategy with bone length preservation.

PURPOSE: The present study investigated the outcomes of bone loss associated with acute open tibial fractures classified as Gustilo-Anderson classification grade III B (GIIIB) using a bone length preservation strategy. METHODS: Among acute GIIIB open tibial fractures, 29 limbs of 29 patients requiring bone loss treatment were included. The reconstruction methods for bone loss were selected among the Masquelet technique (MT), bone transport (BT), acute shortening followed by gradual lengthening (ASGL), and free vascularized fibula graft (FVFG). Primary outcome measures were the rate of bone union and time to bone union. RESULTS: The median radiographic apparent bone gap (RABG) was 46.75 mm. Bone loss was treated with ASGL only in two patients in whom it was not possible to cover large soft tissue defects by a single free latissimus dorsi (LD) myocutaneous flap (with the serratus anterior (SA) muscle). The other 27 patients underwent soft tissue reconstruction and bone loss treatment with the preservation of bone length, including the MT for 23, BT for six, and FVFG for one. The bone union rate was 75.9%, and the median time to bone union was six months. Salvage surgeries were performed on all seven patients with nonunion; all of whom eventually achieved bony union. CONCLUSION: Bone loss associated with acute GIIIB open tibial fractures were treated with "bone length preservation" if the size of the soft tissue defect was less than the size that was covered by a single LD myocutaneous flap (with the SA muscle).

Light-Induced Condensation of Biofunctional Molecules around Targeted Living Cells to Accelerate Cytosolic Delivery.

The light-induced force and convection can be enhanced by the collective effect of electrons (superradiance and red shift) in high-density metallic nanoparticles, leading to macroscopic assembly of target molecules. We here demonstrate application of the light-induced assembly for drug delivery system with enhancement of cell membrane accumulation and penetration of biofunctional molecules including cell-penetrating peptides (CPPs) with superradiance-mediated photothermal convection. For induction of photothermal assembly around targeted living cells in cell culture medium, infrared continuous-wave laser light was focused onto high-density gold-particle-bound glass bottom dishes exhibiting plasmonic superradiance or thin gold-film-coated glass bottom dishes. In this system, the biofunctional molecules can be concentrated around the targeted living cells and internalized into them only by 100 s laser irradiation. Using this simple approach, we successfully achieved enhanced cytosolic release of the CPPs and apoptosis induction using a pro-apoptotic domain with a very low peptide concentration (nM level) by light-induced condensation.

Arthrodesis for Primary Osteoarthritis of Trapeziometacarpal Joint Using Multiple Kirschner Wires and Tension Band Wire in Female Patients Older than 40.

Background: The purpose of this study was to evaluate the results of arthrodesis with multiple Kirschner (K)-wires and tension band wire for primary osteoarthritis of trapeziometacarpal (TM) joint in female patients aged 40 years or older. Methods: We retrospectively obtained data regarding all female patients 40 years or older who underwent TM joint arthrodesis for TM joint osteoarthritis with K-wires and tension band wire over a 10-year period from 2009 till 2019. Thumb length, active range of motion (ROM) at the metacarpophalangeal (MCP) joint, active ROM of radial and volar adduction and abduction and key pinch strength was measured. Patient-reported outcomes were assessed using a pain and satisfaction questionnaire and the DASH score. We also recorded postoperative complications. Results: The study included 60 thumbs in 49 patients with an average age 60 years and a mean follow-up of 40 ± 21 months. All but one thumb had radiographic evidence of fusion within 6 months and the union rate was 98%. Key pinch strength increased from 2.3 to 4.9 kg after surgery. Total arc of motion in radial adduction-abduction decreased from 16° to 10°. Total arc of motion in volar adduction-abduction decreased from 25° to 9°. One patient experienced attritional rupture of the flexor pollicis longus tendon attributed to a K-wire penetration into the carpal tunnel. Although 46 thumbs (77%) had no or mild hardware-related symptoms, they underwent hardware removal after solid bone union. In 23 thumbs with follow-up period longer than 48 months, two thumbs developed scaphotrapeziotrapezoid joint arthritis and two thumbs developed metacarpophalangeal joint arthritis. Conclusions: We found that arthrodesis with multiple K-wires and tension band wire is a valuable option in the management of trapeziometacarpal joint osteoarthritis in female patients aged 40 years or older. Level of Evidence: Level IV (Therapeutic).

Psychometric Evaluation of the Disabilities of the Arm, Shoulder and Hand Outcome Questionnaire for Brachial Plexus Injury Using Rasch Analysis.

Background: Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire is the most widely used patient-reported outcome measure (PROM) for assessment of upper extremity disability assessment. However, DASH is a multidimensional measurement with different difficulty levels and ratio apportionment of the items categorised by ordinal scale. This has caused a misinterpretation of the total disability scores. We created a modified DASH adapted to the Rasch model. The aim of this study is to compare the functional recovery and quality of life (QOL) improvement and to assess the validity of the original DASH and modified DASH between C56/C567, C5-8 and total types of brachial plexus injury (BPI) following surgical reconstruction. Methods: A total of 183 BPI patients who underwent reconstructive surgery were evaluated for functional recovery using the range of motion and power of the affected limb, and improvement in QOL with DASH. The collected data were analysed using Rasch measurement theory to detect the misfit items. The original and modified DASH were compared under the three different types of BPI after item reduction by removing the misfit items. Results: There were significant differences in functional recovery between three types of palsy. However, PROM using DASH score with or without misfit items (12 items) did not show any significant differences. Conclusions: DASH is not suitable for comparison of upper extremity disabilities even after being corrected mathematically due to the inclusion of items from many different domains unequally. Therefore, each item of the function (with or without compensation of the uninjured hand), pain and impact to the patients should be evaluated separately. Level of Evidence: Level IV (Prognostic).

Comminuted Dorsal Ulnar Fragment in Distal Radius Fractures Treated Using the Integrated Compression Screw With a Mini-Plate.

Stabilization for displaced dorsoulnar fragments in distal radius fractures is challenging to treat with conventional volar locking plates alone. The integrated compression screw combined with a volar locking plate has been introduced as an additional tool to stabilize the dorsoulnar fragment and has been reported to work effectively. However, the compression screw is unable to stabilize a comminuted dorsal ulnar fragment; therefore, it is necessary to consider using an additional dorsal plate. We have developed a modified surgical technique to stabilize a comminuted dorsal intra-articular fragment by combining the integrated compression screw with a mini-plate as a washer or a buttress.

Tension Reducing Muscle Stretch Protocol to Obtain Full Distal Tendon Excursion: A New Rehabilitation Protocol after Flexor Tendon Repair.

Background: Flexor tendon rehabilitation protocols minimize repair tension by limiting range of movement to prevent tendon rupture. The resultant muscle contracture inhibits finger extension, increases resistance in tendon gliding distally, and progress to proximal interphalangeal (PIP) joint flexion contracture. This study describes our new rehabilitation protocol, the Tension Reducing Muscle Stretch (TRMS), designed to prevent flexor muscle contracture and obtain full distal tendon excursion. Methods: We reviewed retrospectively 14 fingers in 13 consecutive patients with primary repair of complete zone I or II flexor digitorum profundus (FDP) tendon rupture were treated with our protocol between 2007 and 2019. Our rehabilitation following FDP 4-strand repairs consisted of three steps. The first step comprised of exercises from traditional protocols such as Duran, Kleinert, Synergistic-wrist-motion, and Place-and-hold. The second step comprised the TRMS exercise to prevent the onset of muscle contracture. Anatomically, FDP tendons arise from the same FDP muscle belly. TRMS involved placing the affected finger in full passive flexion while unaffected fingers were passively extended to full extension. This made the affected FDP muscle stretched. The final step incorporated the early active flexion motion exercise, in which simple fisting was performed, from a fully extended position. Results: The mean total active motion at the final follow up was 235° (range 170-265). Using the Strickland criteria, eight achieved excellent, four had good, two had fair results. The mean angle of passive extension deficit at the PIP joint at four weeks after surgery was -7° (-30-0), and at the final follow up was -3° (-20-0). No tendon repair was ruptured. Conclusions: This protocol reduced tension in the affected tendon muscle and encouraged tendon excursion distal to the repair site without complications. It allows full tendon excursion and prevents PIP joint contractures.

The Device of Ethylene Vinyl Acetate Sheet for Trismus Caused by Bilateral Mandible Fractures.

Trismus is commonly caused by temporomandibular joint disorders and maxillofacial fractures. We report the case of a 62-year-old woman with trismus and difficulty in mastication caused by bilateral mandibular fractures. She had a maximal interincisal opening distance (MID) of 22 mm. Mouth-opening training was administered using a novel dental mouth-training device custom-made using ethylene vinyl acetate sheets and according to the dentition and extent of mouth-opening of the patient. After 2 months of training, the MID increased to 42 mm. With adequate training, this device is effective in treating trismus due to scarring.

Damage-free light-induced assembly of intestinal bacteria with a bubble-mimetic substrate.

Rapid evaluation of functions in densely assembled bacteria is a crucial issue in the efficient study of symbiotic mechanisms. If the interaction between many living microbes can be controlled and accelerated via remote assembly, a cultivation process requiring a few days can be ommitted, thus leading to a reduction in the time needed to analyze the bacterial functions. Here, we show the rapid, damage-free, and extremely dense light-induced assembly of microbes over a submillimeter area with the "bubble-mimetic substrate (BMS)". In particular, we successfully assembled 104-105 cells of lactic acid bacteria (Lactobacillus casei), achieving a survival rate higher than 95% within a few minutes without cultivation process. This type of light-induced assembly on substrates like BMS, with the maintenance of the inherent functions of various biological samples, can pave the way for the development of innovative methods for rapid and highly efficient analysis of functions in a variety of microbes.

Upper Extremity Volume/Total Body Volume Ratio for Evaluation of Upper Extremity Lymphedema.

BACKGROUND: Measurement of extremity volume is the most commonly used method for evaluation of lymphedema. However, volumetry would be inappropriate for comparing patients with different physiques, because body-type significantly affects extremity volume. Thus, we cannot evaluate using absolute values. To overcome this problem, we developed a simple index of proportion of the upper-extremity volume to total body volume (upper-extremity volume/total body volume ratio [UVR]) for body type-corrected volume evaluation of upper-extremity lymphedema. The purpose of this study was to compare upper-extremity volume and UVR in nonedematous upper extremities and to establish normative values of UVR in adult women. METHODS: Eighty-five normal female subjects were included in this study. The average age was 38 ± 12 years, and the average body mass index (BMI) was 21.4 ± 2.9. Volumetry of both upper extremities using water displacement method was tested in all subjects. Upper-extremity volume/total body volume ratio was calculated by dividing upper-extremity volume by total body volume. Total body volume was calculated by dividing body weight (g) by body density (g/mL). We used linear regression equation (body density = 1.0560 - 0.0005 × age) to calculate body density. RESULTS: UVR of 170 upper extremities averaged 2.580 ± 0.202%. Although there was significant relationship between upper-extremity volume and BMI, there was no relationship between UVR and BMI. CONCLUSIONS: Although further studies are necessary to establish usefulness of UVR, UVR has a potential to allow better body type-corrected volume evaluation for upper-extremity lymphedema.

Long-Term Outcomes of Successful Fingertip Replantation: A Follow-Up of at Least 10 Years.

BACKGROUND: The purpose of this study was to evaluate the long-term outcome of successful fingertip replantations with more than 10 years of follow-up after surgery. METHODS: A total of 34 successfully replanted digits in 31 patients with a mean period to follow-up of 16.5 years were included in this study. The main outcome measures were time to return to work, pain, cold intolerance, sensory recovery, nail deformity, grip strength, range of motion of the thumb interphalangeal or finger distal interphalangeal joint, fingertip atrophy, nonunion, bone shortening, use in activities of daily living, and patient satisfaction. RESULTS: None of the patients reported chronic pain. No cold intolerance was experienced in 32 digits. Semmes-Weinstein monofilament testing showed recovery of protective sensation in 27 digits. The moving two-point discrimination test showed excellent or good recovery in 91 percent of the patients. Sensory recovery was satisfactory, and there was no significant difference regardless of nerve repair or injury type. Moderate to severe nail deformity was found in six digits. Fingertip atrophy was evaluated by comparing the volume of the replanted fingertip with the contralateral digit. The volume was 82 ± 17 percent of the contralateral normal side. There was no significant difference in the volume comparing the level of amputation, injury type, or incidence of postoperative vascular complication. Ninety-seven percent of the patients were satisfied with the results. CONCLUSION: Long-term outcome of fingertip replantation more than 10 years after surgery was found to be favorable.

A Bilobed Pedicled Groin Flap for Reconstruction of Forearm Skin Defects following Replantation.

The versatility of a pedicled groin flap can be further increased by raising it in a bilobed fashion. This allows the flap to cover both the volar and dorsal surfaces of a hand or forearm defect. A 48-year-old man sustained an avulsion amputation of his right forearm by a rolling machine in a workplace accident. Replantation of the right forearm was performed, and the postoperative course was uneventful. Unfortunately, the wound healing was complicated by circumferential marginal skin necrosis, which was confined to the distal forearm. A bilobed pedicled groin flap was performed for the wound coverage because reconstruction with a free flap would be very risky as the vessels were avulsed from the proximal part of the forearm. A good functional recovery of the hand and fingers was noted at 12 months' follow-up. The advantages of a bilobed pedicle groin flap are that it allows coverage of both the volar and dorsal surfaces at one setting and primary closure of the donor site is possible. Furthermore, a long tube-shaped pedicle in this flap can reduce the patient discomfort and prevent finger stiffness by allowing a range of motion exercise. In conclusion, the bilobed pedicled groin flap is a useful option to cover soft tissue defects involving both the volar and dorsal surfaces over the mid- to distal forearm, especially when the free flap is contraindicated.

Contralateral Obturator Nerve to Femoral Nerve Transfer for Restoration of Knee Extension After Acute Flaccid Myelitis: A Case Report.

CASE: A 7-year-old boy presented with left femoral and obturator nerves (ONs) palsy after an asthmatic attack with a viral prodrome, and his right lower limb was unaffected. He was diagnosed with acute flaccid myelitis (AFM) after positive spinal magnetic resonance imaging findings. After contralateral ON to femoral nerve transfer (CONFNT), his left quadriceps was reinnervated at 5.5 months, full knee extension was recovered at 14 months, and good functional outcomes were achieved at 31 months. CONCLUSIONS: This first clinical report on CONFNT demonstrated a feasible good alternative in treating young patients with AFM with unilateral L2-L4 palsy and short duration of deficit.

Surgical Reconstruction for Upper-Extremity Paralysis Following Acute Flaccid Myelitis.

Acute flaccid myelitis (AFM) is a debilitating illness that is defined by the sudden onset of flaccid paralysis in the extremities with spinal magnetic resonance imaging (MRI) demonstrating a longitudinal lesion confined to the gray matter. The purpose of this study was to report the types of upper-extremity palsy and outcomes of surgical reconstruction in patients with AFM. METHODS: Eight patients with a median age at onset of 3.8 years (range, 2.3 to 9.9 years) were identified. There was loss of shoulder abduction and external rotation in all patients, loss of elbow flexion in 5 patients, complete or partial loss of hand function in 3 patients, and spinal accessory nerve palsy in 2 patients. All patients underwent surgical reconstruction, which was categorized into 3 main groups: nerve transfer, secondary muscle transfer, and free muscle transfer. RESULTS: The median follow-up period was 39 months (range, 30 to 94 months). Four patients obtained ≥90° of shoulder abduction whereas the other 4 patients had shoulder abduction of ≤70°. The 5 patients who received free muscle transfer or nerve transfer to restore elbow function obtained ≥140° of elbow flexion. Two patients treated with free muscle transfer to restore finger function obtained satisfactory total active motion of the fingers (180°). CONCLUSIONS: The patterns of paralysis and the strategy and outcomes of surgical reconstruction for patients with AFM differed from those for traumatic and obstetric brachial plexus palsy. All patients had loss of shoulder abduction, and 2 had spinal accessory nerve palsy. Restoration of shoulder function was unpredictable and depended on the quality of the donor nerves and recovery of synergistic muscles. Restoration of elbow and hand function was more consistent and satisfactory. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete list of levels of evidence.

Isolation and characterization of Vasa in the frog Rana rugosa.

We cloned a cDNA encoding Vasa, a member of the DEAD (Asp-Glu-Ala-Asp) family of proteins, from the ovary of the frog Rana rugosa. Comparative alignment of amino acid sequences with known Vasa from several species of vertebrate showed that the R. rugosa orthologue shares eight conserved regions with Vasa from other vertebrates. Vasa gene expression was restricted to the testis and ovary among ten different tissues examined. Vasa expression showed no sexual dimorphism during sex determination in R. rugosa, but became higher in the ovary thereafter. By Western blot analysis, a single Vasa band with a molecular weight of 80.9 kDa was detected. The same antibody immunohistochemically detected Vasa in a few cells in the embryonic endoderm at stage 15; the beginning of closure of neural folds, and in the cytoplasm of spermatogonia in the testis, and oocytes in the ovary of tadpoles at stage XX; marked by one or both forelegs protruded. Together, these results suggest that Vasa is a highly specific marker of germ cells and hence useful for studies of germ cell specification and function in amphibians as it already is in other species of both invertebrates and vertebrates such as Drosophila and zebrafish.