The contribution of inner electron excitation to the electronic stopping power of palladium for protons.

The electronic stopping power of palladium (Pd) for protons is investigated based on time-dependent density functional theory combined with Ehrenfest molecular dynamics simulations. The electronic stopping power of Pd with explicitly considering inner electrons for protons is calculated and the excitation mechanism for the inner electrons of Pd is revealed. The velocity proportionality of the low-energy stopping power of Pd is reproduced. Our study verified that the inner electron excitation contributes significantly to the electronic stopping power of Pd in the high energy range, which is strongly dependent on the impact parameter. The electronic stopping power obtained from the off-channeling geometry is in quantitative agreement with the experimental data in a wide velocity range, and the discrepancy around the stopping maximum is further reduced by considering the relativistic correction on the binding energy of inner electrons. The velocity dependence of the mean steady-state charge of protons is quantified, and the results showed that the participation of 4p-electrons reduces the mean steady-state charge of protons, and consequently decreases the electronic stopping power of Pd in the low energy range.

PBQ-Enhanced QUIC: QUIC with Deep Reinforcement Learning Congestion Control Mechanism.

Currently, the most widely used protocol for the transportation layer of computer networks for reliable transportation is the Transmission Control Protocol (TCP). However, TCP has some problems such as high handshake delay, head-of-line (HOL) blocking, and so on. To solve these problems, Google proposed the Quick User Datagram Protocol Internet Connection (QUIC) protocol, which supports 0-1 round-trip time (RTT) handshake, a congestion control algorithm configuration in user mode. So far, the QUIC protocol has been integrated with traditional congestion control algorithms, which are not efficient in numerous scenarios. To solve this problem, we propose an efficient congestion control mechanism on the basis of deep reinforcement learning (DRL), i.e., proximal bandwidth-delay quick optimization (PBQ) for QUIC, which combines traditional bottleneck bandwidth and round-trip propagation time (BBR) with proximal policy optimization (PPO). In PBQ, the PPO agent outputs the congestion window (CWnd) and improves itself according to network state, and the BBR specifies the pacing rate of the client. Then, we apply the presented PBQ to QUIC and form a new version of QUIC, i.e., PBQ-enhanced QUIC. The experimental results show that the proposed PBQ-enhanced QUIC achieves much better performance in both throughput and RTT than existing popular versions of QUIC, such as QUIC with Cubic and QUIC with BBR.

Distinct stress-related medial prefrontal cortex activation in women with depression with and without childhood maltreatment.

BACKGROUND: Emerging evidence has highlighted the moderating effect of childhood maltreatment (CM) in shaping neurobiological abnormalities in major depressive disorder (MDD). However, whether neural mechanisms underlying stress sensitivity in MDD are affected by the history of CM is unclear. METHODS: Two hundred and thirteen medication-free female participants were recruited for a functional magnetic resonance imaging study assessing the effects of psychosocial stress on neural responses. The Montreal Imaging Stress Task was administrated to 44 female MDD patients with CM (MDD/CM), 32 female MDD patients without CM (MDD/noCM), 43 female healthy controls (HCs) with CM (HC/CM), and 94 female HCs without CM (HC/noCM). A CM (CM, noCM) × diagnosis (MDD, HC) whole-brain voxel-wise analysis was run to assess putative group differences in neural stress responses. RESULTS: A significant CM × Diagnosis interaction emerged in the medial prefrontal cortex (mPFC). Bonferroni-corrected simple effects analysis clarified that (1) the MDD/CM group had less mPFC deactivation than the HC/CM group, (2) the MDD/noCM group exhibited greater mPFC deactivation than the HC/noCM group, and (3) the MDD/CM group exhibited less mPFC deactivation relative to the MDD/noCM group. In addition, the mPFC-seed psychophysiological interaction analysis revealed that individuals in the CM groups had significantly greater stress-related mPFC-left superior frontal gyrus and mPFC-right posterior cerebellum connectivity relative to the noCM groups. CONCLUSIONS: Findings highlight distinct neural abnormalities in MDD depending on prior CM history, particularly potentiated stress-related mPFC recruitment among MDD individuals reporting CM. Moreover, CM history was generally associated with the disruption in functional connectivity centered on the mPFC.

Congenital Contracture of the Ulnar Digits and Its Differentiation From Ischemic Contracture.

PURPOSE: To describe the clinical features, radiologic findings, differential diagnosis, and surgical treatment of a congenital flexion deformity of the middle, ring, and little fingers. The cause of the condition is the aberrant origin of the flexor digitorum profundus, leading to a congenital contracture of the ulnar digits. METHODS: We reviewed 8 patients with congenital contracture of the ulnar digits. The mean age at the time of surgery was 14 years. An examination revealed a flexion contracture of the middle, ring, and small fingers. Plain radiographs, 3-dimensional computed tomography, magnetic resonance imaging, and ultrasound were used to characterize bony and soft tissue pathology. Surgical treatments included resection of the aberrant origin and a muscle-sliding procedure. RESULTS: Bony prominence on the proximal ulna was seen in the plain radiographs and/or 3-dimensional computed tomography. A cord that extended from this bony prominence to the tendons of flexor digitorum profundus was revealed in the magnetic resonance imaging. The bony prominence and the cord were also seen using ultrasound. The median time of patient follow-up was 1.7 years. A simple resection of the tendinous origin only resulted in a release in 2 patients who were 4 years old. Older patients required a further muscle-sliding procedure. The average grip strength ratio on the contralateral side was 82%. CONCLUSIONS: Congenital contracture of the ulnar digits is a new congenital flexion deformity involving the middle, ring, and small fingers. Bony prominence on the proximal ulna is the key finding for establishing its diagnosis and distinguishing it from an ischemic contracture. We recommend treating this surgically at 12 years of age or older after the phase of rapid growth of the extremities. We recommend the resection of the aberrant origin, combined with a muscle-sliding procedure, as the treatment of choice, even for young patients. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic V.

An improved PCR-CTPP assay for the detection of ADH1B Arg48His polymorphism.

BACKGROUND: ADH1B Arg48His polymorphism is associated with the development of alcohol-related diseases. In this study, we aimed to explore an improved polymerase chain reaction with confronting two-pair primers (PCR-CTPP) assay for the detection of ADH1B Arg48His polymorphism. METHODS: A mismatch was introduced at the 3' end of each of the two allele-specific to increase the specificity of the reaction. But beyond that, a new mismatch at-3 positions of outer primers was designed to decrease the efficiency of the aforementioned primers and depresses the amplification of an internal nonspecific DNA control. A total of 180 samples from healthy volunteers Han Chinese were tested to evaluate this new assay. RESULTS: The protocol of PCR-CTPP was successful for genotyping of ADH1B Arg48His. The results from the improved PCR-CTPP assay were confirmed by Sanger sequencing, and correct genotyping rates were 100%.The genotype frequencies were 49.44% (89 cases) for His/His, 46.67% (84 cases) for Arg/His, and 3.89% (seven cases) for Arg/Arg respectively. CONCLUSIONS: This improved PCR-CTPP assay is simple, rapid, cost-effective, and reliable, specific for the detection of ADH1B Arg48His polymorphism in most clinical diagnostic laboratories.

Endometriosis Mimicking Soft-Tissue Neoplasms: A Potential Diagnostic Pitfall.

Endometriosis is a common gynecological disorder most often involving the pelvic region. Although it is rare, endometriosis occurring outside of the peritoneal cavity most commonly occurs within scars of the abdominal wall, but it has been reported in the lungs, pleura, kidneys, brain, and the extremities. Herein, we present 2 cases of endometriosis, including 1 case of endometriosis of the wrist that clinically mimicked a soft-tissue neoplasm and 1 case of right-groin endometriosis mimicking synovial sarcoma during the initial pathological interpretation of findings on fine needle aspiration. We also report on a third patient with synovial sarcoma to demonstrate a diagnostic pitfall. To our knowledge, endometriosis within the skeletal muscle of the wrist has not been previously reported in the literature. A literature review was performed, and we discuss how this diagnostic pitfall may be avoided. We review the techniques for diagnosing synovial sarcoma and the importance of a high index of suspicion for endometriosis when investigating any soft-tissue mass in a female patient of reproductive age. Adequate pathological evaluation in conjunction with the correlating clinical and radiological information should help facilitate an accurate diagnosis.

Classification of Hamate Fractures: An Analysis of 247 Patients with Hamate Fractures.

Background: We devised a new classification of hamate fractures named the TOUCH classification. Each letter of this acronym depicts a fracture type - Type I (Transverse fracture), Type II (Open and/or complex fracture), Type III (Ulnar/medial tuberosity fracture), Type IV (Coronal fracture) and Type V (Hook fracture). Each fracture type was further divided into two or three subtypes (a, b, and/or c) based on degree of severity. The aim of this study is to classify the hamate fractures treated at our centre using this classification. Methods: A retrospective review of all patients with hamate fractures treated at our hospital between 2003 and 2022 was done. Patient data with regard to age, gender, mechanism of injury, injured limb and any associated injuries was collected. Hamate fractures were classified based on the TOUCH classification. Results: A total of 247 patients with hamate fractures were included. Patients in the age group of 20-40 years accounted for 73.6% of all fractures. Female patients accounted for only 6.9% of all fractures and 76.5% of women with hamate fractures were older than 40 years. The incidence of hamate fracture tended to increase with age in women. The most common mechanism of injury was a fall (69 patients). The injury involved the right upper limb in 195 patients. And 164 patients had associated injuries in the same upper limb. Type III (coronal fracture of the hamate body) accounted for 57.4%, followed by type V (hook of hamate fracture) in 26.7% of patients. Conclusions: The TOUCH classification could cover all kinds of hamate fractures. It is easy to remember and may guide surgeons in considering treatment options. Level of Evidence: Level IV (Diagnostic).

Clinical Features and Classification of Proximal Carpal Fracture Dislocation Through the Radiocarpal Joint.

Background: The most common types of wrist dislocation are trans-scaphoid lunate dislocation (TLD) and trans-scaphoid perilunate dislocation, in which the lunate and proximal scaphoid are dislocated through the midcarpal joint. There is another rare type of dislocation in which the proximal carpi are dislocated through the radiocarpal joint. The purpose of this study is to examine the clinical features of this type of dislocation. Methods: Six cases of the proximal carpal fracture dislocation via the radiocarpal joint were retrospectively reviewed. All patients underwent open reduction and internal fixation with the ligament reconstruction. A Mayo wrist score was assigned to each patient based on the assessment of pain, functional status, range of motion and grip strength at the last follow-up. Clinical subjective evaluation of function and pain was assessed using the patient-rated wrist evaluation (PRWE) method. Results: All patients were male and injured with a median age of 33.5 years. The median follow-up period was 10 months. There were three types of dislocations: Scaphoid fracture dislocation, TLD and scaphoid-lunate dislocation. All patients had satisfactory results with an average PRWE of 7.2 ± 4.7. The preoperative VAS was 6.7 ± 1.0 and the postoperative VAS was 0.7 ± 0.7 (p < 0.01). Postoperative grip strength accounted for 89.2% ± 9.8% of the contralateral side; the Mayo wrist score averaged 90.0 ± 6.5, with four patients obtaining excellent and two good results. Conclusions: Fracture dislocation of the proximal carpal bones through the radiocarpal joint is an independent type of wrist dislocation that tends to occur in young men with high-energy impact. The wrist is most often injured in a pronation hyperextension position. If treatment is timely and appropriate, the prognosis is quite good. Level of Evidence: Level IV (Therapeutic).

Role of Vickers Ligament in the Pathogenesis of Madelung Deformity.

OBJECTIVE: The Vickers ligament is thought to hinder the growth of palmar ulnar radius by tethering the lunate to the radius, leading to Madelung deformity. The purpose of this study was to clarify the nature of the Vickers ligament and investigate its pathogenesis in Madelung deformities based on our observation of the Vickers ligament. METHODS: All 22 patients (33 wrists) with Madelung deformities treated surgically between 2018 and 2022 were included. The diagnosis was confirmed radiographically in all patients. The three-dimensional computed tomography (3D-CT) data of 16 patients (19 wrists) were available. Magnetic resonance imaging (MRI) data were available for 9 patients (14 wrists). Wrist arthroscopy was used in 4 patients. The Vickers ligament was resected and submitted for histopathological examination in 8 patients. Radiographic outcomes, 3D-CT, MRI, arthroscopy, surgical findings, and histopathology of the Vickers ligament were evaluated. RESULTS: The 3D-CT revealed that the Vickers ligament originated in the metaphysis and formed a metaphyseal defect at the palmar ulnar radius. In the sequential MR coronal images, the Vickers ligament could be divided into 3 branches, extending to the lunate, triquetrum and ulnar styloid. Arthroscopy and surgical findings revealed that the nature of the Vickers ligament was the stretched palmar ligament of the wrist. The histopathology results revealed ligamentous tissue and fibrocartilaginous metaplasia with a structure similar to that of the triangular fibrocartilage complex (TFCC). CONCLUSIONS: The Vickers ligament is not a separate aberrant ligament. The nature of the Vickers ligament is a combination of the stretched TFCC ligament (palmar radioulnar ligament, ulnotriquetral ligament and ulnolunate ligament) and radiolunate ligament. The possible pathogenesis of Madelung deformity might be focal early epiphyseal closure at the middle part of the sigmoid notch, which leads to focal growth retardation of the radius and pulls palmar ligaments proximally to form the Vickers ligament.

Sex-specific resting state brain network dynamics in patients with major depressive disorder.

Sex-specific neurobiological changes have been implicated in Major Depressive Disorder (MDD). Dysfunctions of the default mode network (DMN), salience network (SN) and frontoparietal network (FPN) are critical neural characteristics of MDD, however, the potential moderating role of sex on resting-state network dynamics in MDD has not been sufficiently evaluated. Thus, resting-state functional magnetic resonance imaging (fMRI) data were collected from 138 unmedicated patients with first-episode MDD (55 males) and 243 healthy controls (HCs; 106 males). Recurring functional network co-activation patterns (CAPs) were extracted, and time spent in each CAP (the total amount of volumes associated to a CAP), persistence (the average number of consecutive volumes linked to a CAP), and transitions across CAPs involving the SN, DMN and FPN were quantified. Relative to HCs, MDD patients exhibited greater persistence in a CAP involving activation of the DMN and deactivation of the FPN (DMN + FPN-). In addition, relative to the sex-matched HCs, the male MDD group spent more time in two CAPs involving the SN and DMN (i.e., DMN + SN- and DMN-SN + ) and transitioned more frequently from the DMN + FPN- CAP to the DMN + SN- CAP relative to the male HC group. Conversely, the female MDD group showed less persistence in the DMN + SN- CAP relative to the female HC group. Our findings highlight that the imbalance between SN and DMN could be a neurobiological marker supporting sex differences in MDD. Moreover, the dominance of the DMN accompanied by the deactivation of the FPN could be a sex-independent neurobiological correlate related to depression.

A Cadaveric Feasibility Study of an Automatic Multi-Degrees of Freedom Surgical Robot for Percutaneous Scaphoid Guide Pin Insertion.

Background: Percutaneous fixation of scaphoid fractures need accurate guide pin insertion. The emergence of computer-assisted navigation and robotic surgery may provide a promising solution to this problem. Methods: This study presents the development of an automatic multi-degrees of freedom (DOF) surgical robot with computer-assisted navigation system, focusing on percutaneous scaphoid guide pin insertion. Using this device, along with a 3D fluoroscopy unit, we have conducted an experimental study on 10 cadavers for percutaneous scaphoid guide pin insertion to verify the feasibility and reliability of the system. Results: The mean operative duration was 29.1 (SD 4.3) minutes. The cadavers required no more than two attempts to achieve desired wire placement, with the mean positioning-error being 2.0 (SD 0.3) mm and the mean angle-deviation 3.6 (SD 0.7)°. Throughout the study, a mean of 2.2 full-cycle fluoroscopy attempts was required for each cadaver during surgery, and no preoperative CT scan was needed. Conclusions: The outcomes show that using the automatic surgical robot to perform the percutaneous scaphoid guide pin insertion is feasible and desired results can be achieved.

Intravenous immunoglobulin is safe and effective in controlling pre-existing paraneoplastic neuromuscular diseases in cancer patients treated with immune checkpoint inhibitors: two case reports and literature review.

Immune checkpoint inhibitors cause rare but potentially fatal neuromuscular complications, leading to a concern to use these agents in cancer patients with pre-existing autoimmune or inflammatory neuromuscular diseases. We report two such patients with paraneoplastic dermatomyositis and "seronegative" paraneoplastic demyelinating neuropathy, respectively, who have been successfully treated with immune checkpoint inhibitor monotherapy as well as maintenance intravenous immunoglobulin. While controlling the paraneoplastic or autoimmune neuromuscular diseases, the use of intravenous immunoglobulin did not compromise the anti-cancer effect of immune checkpoint inhibitor.

Trait- and state-like co-activation pattern dynamics in current and remitted major depressive disorder.

BACKGROUND: Distinguishing between trait- and state-like neural alternations in major depressive disorder (MDD) may advance our understanding of this recurring disorder. We aimed to investigate dynamic functional connectivity alternations in unmedicated individuals with current or past MDD using co-activation pattern analyses. METHODS: Resting-state functional magnetic resonance imaging data were acquired from individuals with first-episode current MDD (cMDD, n = 50), remitted MDD (rMDD, n = 44), and healthy controls (HCs, n = 64). Using a data-driven consensus clustering technique, four whole-brain states of spatial co-activation were identified and associated metrics (dominance, entries, transition frequency) were analyzed with respect to clinical characteristics. RESULTS: Relative to rMDD and HC, cMDD showed increased dominance and entries of state 1 (primarily involving default mode network (DMN)), and decreased dominance of state 4 (mostly involving frontal-parietal network (FPN)). Among cMDD, state 1 entries correlated positively with trait rumination. Conversely, relative to cMDD and HC, individuals with rMDD were characterized by increased state 4 entries. Relative to HC, both MDD groups showed increased state 4-to-1 (FPN to DMN) transition frequency but reduction in state 3 (spanning visual attention, somatosensory, limbic networks), with the former metric specifically related to trait rumination. LIMITATIONS: Further confirmation with longitudinal studies are required. CONCLUSIONS: Regardless of symptoms, MDD was characterized by increased FPN-to-DMN transitions and reduced dominance of a hybrid network. State-related effect emerged in regions critically implicated in repetitive introspection and cognitive control. Asymptomatic individuals with past MDD were uniquely linked to increased FPN entries. Our findings identify trait-like brain network dynamics that might increase vulnerability to future MDD.

Persistent Ventral Anterior Cingulate Cortex and Resolved Amygdala Hyper-responses to Negative Outcomes After Depression Remission: A Combined Cross-sectional and Longitudinal Study.

BACKGROUND: Major depressive disorder (MDD) is a highly prevalent mood disorder affecting more than 300 million people worldwide. Biased processing of negative information and neural hyper-responses to negative events are hallmarks of depression. This study combined cross-sectional and longitudinal experiments to explore both persistent and resolved neural hyper-responses to negative outcomes from risky decision making in patients with current MDD (cMDD) and remitted MDD (rMDD). METHODS: A total of 264 subjects participated in the cross-sectional study, including 117 patients with medication-naïve, first-episode current depression; 45 patients with rMDD with only 1 episode of depression; and 102 healthy control subjects. Participants completed a modified balloon analog risk task during functional magnetic resonance imaging. In the longitudinal arm of the study, 42 patients with cMDD were followed and 26 patients with rMDD were studied again after 8 weeks of antidepressant treatment. RESULTS: Patients with cMDD showed hyper-responses to loss outcomes in multiple limbic regions including the amygdala and ventral anterior cingulate cortex (vACC). Amygdala but not vACC hyperactivity correlated with depression scores in patients with cMDD. Furthermore, amygdala hyperactivity resolved while vACC hyperactivity persisted in patients with rMDD in both cross-sectional and longitudinal studies. CONCLUSIONS: These findings provide consistent evidence supporting differential patterns of amygdala and vACC hyper-responses to negative outcomes during depression remission. Amygdala hyperactivity may be a symptomatic and state-dependent marker of depressive neural responses, while vACC hyperactivity may reflect a persistent and state-independent effect of depression on brain function. These findings offer new insights into the neural underpinnings of depression remission and prevention of depression recurrence.

Sex-specific neural responses to acute psychosocial stress in depression.

Major Depressive Disorder (MDD) is characterized by increased stress sensitivity. Emerging findings in healthy adults suggest that stress responses within limbic/striatal-prefrontal regions are moderated by sex and unfold over time. Thus, we hypothesized that stress response abnormalities in MDD might be affected by sex and stress exposure time. The Montreal Imaging Stress Task was administered to 124 unmedicated patients with first-episode MDD (76 females) and 243 healthy controls (HC; 137 females) during functional magnetic resonance imaging (fMRI). Based on prior studies, amygdala, hippocampus, medial orbitofrontal cortex (mOFC), nucleus accumbens (NAc) and dorsolateral prefrontal cortex (dlPFC) were selected as a priori regions of interest. In a complementary approach, we probed the effects of stress on the frontoparietal network (FPN) and a network including the amygdala, NAc and anterior cingulate cortex (ACC). Across groups, males exhibited higher dlPFC activity and right FPN amplitude than females. Relative to female HCs, the female MDD group had less deactivation in limbic/striatal regions (amygdala, NAc, hippocampus, Amygdala-NAc-ACC network). Furthermore, unlike female HCs, the female MDD group failed to show a significant increase of deactivation over stress exposure time in the amygdala, mOFC and NAc. Our findings confirm the importance of considering sex differences when investigating neural stress responses. Case-control differences in neural stress responses observed in females (but not males) provide insights into sex differences in the etiology and pathophysiology of depression. The failure to deactivate limbic/NAc regions in depressed females point to dysfunction of adaptive stress responses over stress exposure time.

Identification of Novel FBN2 Variants in a Cohort of Congenital Contractural Arachnodactyly.

Congenital contractural arachnodactyly (CCA) is a rare autosomal dominant disorder of connective tissue characterized by crumpled ears, arachnodactyly, camptodactyly, large joint contracture, and kyphoscoliosis. The nature course of CCA has not been well-described. We aim to decipher the genetic and phenotypic spectrum of CCA. The cohort was enrolled in Beijing Jishuitan Hospital and Peking Union Medical College Hospital, Beijing, China, based on Deciphering disorders Involving Scoliosis and COmorbidities (DISCO) study (http://www.discostudy.org/). Exome sequencing was performed on patients' blood DNA. A recent published CCA scoring system was validated in our cohort. Seven novel variants and three previously reported FBN2 variants were identified through exome sequencing. Two variants outside of the neonatal region of FBN2 gene were found. The phenotypes were comparable between patients in our cohort and previous literature, with arachnodactyly, camptodactyly and large joints contractures found in almost all patients. All patients eligible for analysis were successfully classified into likely CCA based on the CCA scoring system. Furthermore, we found a double disease-causing heterozygous variant of FBN2 and ANKRD11 in a patient with blended phenotypes consisting of CCA and KBG syndrome. The identification of seven novel variants broadens the mutational and phenotypic spectrum of CCA and may provide implications for genetic counseling and clinical management.

[Clinical classification and treatment experience of wrist gouty arthritis].

OBJECTIVE: To explore the clinical characteristics, clinical classification, and treatment of wrist gouty arthritis. METHODS: The clinical data of 24 patients with wrist gouty arthritis and complete follow-up between April 2011 and August 2020 were retrospectively analyzed. There were 21 males and 3 females; the first onset age was 21-72 years, with a median age of 50 years. There were 15 cases of simple wrist joint disease, and 9 cases of other joints (hand, knee, ankle, metatarsophalangeal joint) involvement; 19 cases of wrist joint as the first site. Except for 1 patient with a medical history of 21 years, the time from onset to diagnosis in the remaining 23 patients was 7 days to 9 years, with a median time of 2 months. According to the clinical manifestations, imaging manifestations, lesion range, and intraoperative wrist arthroscopy manifestations of wrist gouty arthritis, they were classified into 5 types from mild to severe. Among the 24 patients, 13 were type Ⅰ, 2 were type ⅡA, 3 were type ⅡB, 2 were type ⅢA, 3 were type Ⅳ, and 1 was type Ⅴ. The time from first onset to diagnosis for type Ⅰ and type Ⅱ patients was (12.7±40.1) months, and for type Ⅲ-Ⅴ patients was (152.0± 88.5) months, the difference was significant ( t=-4.355, P=0.001). Thirteen patients with type Ⅰ received conservative treatment (including diet, exercise, lifestyle intervention, and medication), and 11 patients with type Ⅱ-Ⅴ received surgical treatment (including 1 case of arthroscopic synovial membrane and gout crystal clearing, 1 case of ligament repair, 5 cases of lesion debridement/artificial bone grafting and filling, 3 cases of wrist fusion, and 1 case of tophicectomy). Before and after treatment, the visual analogue scale (VAS) score was used to evaluate the improvement of wrist joint pain; and the range of motion of the wrist joint (including palmar flexion, dorsal extension, radial deviation, and ulnar deviation) was evaluated. RESULTS: Thirteen conservatively treated patients were followed up 10 months to9 years, with an average of 2.2 years. The VAS scores before treatment and at last follow-up were 6.8±0.7 and 2.9±0.9, respectively, and the difference was significant ( t=12.309, P=0.000). During follow-up, there was no wrist bone and wrist joint damage; wrist joint range of motion basically reached normal. At last follow-up, the wrist joint palmar flexion, dorsal extension, radial deviation, and ulnar deviation significantly improved when compared with the values before treatment ( P<0.05). Eleven surgically treated patients were followed up 5 months to 9 years, with an average of 4.9 years. The swelling and pain of all patients fully relieved, and the VAS scores were 7.3±0.8 before operation, 2.7±0.6 at 1 month after operation, and 2.5±0.6 at last follow-up, which significantly improved after operation ( P<0.05); there was no significant difference between 1 month after operation and last follow-up ( P>0.05). Excluded 3 patients who underwent wrist fusion, the other 8 patients had significantly improved wrist joint palmar flexion, dorsal extension, radial deviation, and ulnar deviation at last follow-up ( P<0.05). The patient's subjective satisfaction with the surgical results reached 100%. CONCLUSION: A missed diagnosis or misdiagnosis of wrist gouty arthritis will greatly damage the wrist stability and functions. Early and proper interventions can effectively retard the progress of the disease. For the late-stage cases, a staged surgical protocol is recommended.

Histopathology Findings of the Lunate in Stage III Kienböck's Disease.

Background: The etiology and natural history of Kienböck's disease remain unclear. Traditionally it has been defined as avascular necrosis of the lunate. The authors tried to demonstrate different tissue distribution, the area ratio of necrotic tissue and vessel counts inside the whole Kienböck lunate to reveal a dynamic process of the lunate collapse. Methods: Five lunates from patients with stage III Kienböck's disease and one cadaveric lunate not involved by Kienböck's disease were sampled. They were sectioned, H&E stained, and evaluated. The thickness of trabecular bone and the area of necrotic tissue were measured with Image-Pro Plus. The number of vessels was counted manually. Results: In the normal lunate, the bone trabeculae showed a uniform distribution with fatty marrow filled the interspace between the trabeculae. In the lunates with Kienböck disease, the trabeculae fracture and necrosis located in the central part with massive fibrous granular tissue proliferation. There were also some chondroid metaplasia at the palmar and dorsal ends. The trabeculae of the lunates of the Kienböck's disease [0.188 mm (0.153 mm, 0.236 mm)] was significantly thicker than the normal lunates [0.146 mm (0.124 mm, 0.164 mm)]. The necrosis was localized around the fracture sites instead of the whole lunate. The mean necrosis area only accounts for 16.3% ± 8.9% of the whole section. Such kind of focal necrosis is quite similar to those around the traumatic fracture ends of other bones. Even in stage III Kienböck lunates, the vessels are quite abundant (221 ± 42 in one sagittal section), while the vessels inside the normal lunate were 352 ± 28. Conclusions: There is neither massive nor obvious generalized avascular bone necrosis in our histopathology observations. The focal necrosis and vessel damage were more likely associated with the broken trabeculae inside the lunate. Based on our histopathology observations, we suggested that the progressive process of Kienböck's disease could be described as lunate nonunion advanced collapse instead of avascular necrosis.