Rasch analysis of the carpal tunnel syndrome instrument.

BACKGROUND: The carpal tunnel syndrome instrument (CTSI) is the most widely used patient-reported outcome measure (PROM) in carpal tunnel syndrome (CTS). However, CTSI is an ordinal-type questionnaire and might have caused misinterpretations of the PROM between surgical outcomes of CTS (Camitz and extra/open carpal tunnel release). PURPOSE: This study aims to convert the CTSI to an interval scale using Rasch analysis (RA) and evaluate the outcome differences between the original and transformed scales. STUDY DESIGN: Prospective control study. METHODS: Four hundred twenty-four patients with 567 CTSs had been interviewed for CTSI perioperatively and treated with either endoscopic/open carpal tunnel release or Camitz tendon transfer. Each CTSI was analyzed for dimensionality, fit statistics, and a transformation of the ordinal-to-interval scale by RA. We compared the two groups perioperative scores of three CTSI versions (original 11-item, modified 8-item, and transformed 8-item). RESULTS: Based on the RA, the original CTSI was not unidimensional. We identified two dimensions. After removing misfit items, the perioperative course of each score by three versions of each dimension was compared (Repeated 2-factor analysis of variance). The transformed interval scales of CTSI provided different assessments of score changes from the ordinal scale of CTSI analyses. CONCLUSIONS: Original CTSI consisted of ordinal scale items that yielded different conclusions than scores converted to interval scale by Rasch analysis. CTSI should convert into an interval scale after reclassifying dimensionality by Latent Factor Analysis and removing misfit items.

Distal radioulnar joint translation evaluated by maximum intensity projection images of computed tomography.

This study compared distal radioulnar joint (DRUJ) translation measured using the subluxation ratio (SR) method between maximum intensity projection (MIP) and conventional CT images on 30 wrists with ulnar positive variance. The results show that DRUJ translation can be reliably evaluated with MIP.

Plexiform Schwannoma of Digital Nerve.

Plexiform schwannoma is an uncommon benign tumour that grows in a plexiform pattern. We report a 47-year-old man with a mass on the palmar aspect of the metacarpophalangeal joint of the right index finger that had been growing gradually for more than 10 years. The mass was palpated from the distal carpal tunnel to the ulnar aspect of the proximal interphalangeal joint of the index finger, with tingling and numbness sensation. The tumour was a multinodular tumour involving the first common palmar digital nerve to the ulnar proper palmar digital nerve. It was resected and reconstructed with a sural nerve graft. Plexiform schwannoma is rare in the digital nerve, with only six cases reported. Generally, classic schwannomas can be enucleated without causing neurologic deficits; however, plexiform schwannoma may require nerve resection. There have been reports of recurrence of plexiform schwannoma; definitive resection and long-term follow-up are necessary. Level of Evidence: Level V (Therapeutic).

Arthroscopic Removal of a Missed Wooden Foreign Body in the Metacarpophalangeal Joint.

We report a case of a missed wooden foreign body in the metacarpophalangeal (MP) joint of the right little finger following a workplace injury. The patient presented to our institution with a persisted pain and limited range of motion of the MP joint 1 week following the injury. Plain radiographs detected no foreign body or fractures. However, detailed examination as ultrasonography (USG) and computed tomography revealed the presence of a foreign body of 10 × 1.5 mm size in the MP joint capsule. The excision of the radiolucent foreign body was performed arthroscopically and was confirmed successful removal using intraoperative USG. The foreign body was recognized as a wooden piece. The patient was immediately pain free postoperatively and regained full range of motion. Arthroscopy can be a practical, reliable method to remove a radiolucent foreign body located in a small joint in a minimally invasive manner, and USG can help surgeons confirm no remnants left.

Re-evaluation of the Indications for the Camitz Procedure in Severe Carpal Tunnel Syndrome.

PURPOSE: The modified Camitz procedure has been used to improve thumb opposition in patients with severe carpal tunnel syndrome (CTS), although its indications remain controversial. This study compared the functional recovery of thumb opposition following carpal tunnel release with and without a concomitant Camitz procedure. We used the Carpal Tunnel Syndrome Instrument questionnaire (CTSI) and the compound muscle action potential of the abductor pollicis brevis (APB-CMAP) to assess the recovery. METHODS: Five hundred sixty-seven hands underwent surgical treatment for CTS following electrophysiologic studies and the CTSI. The procedures included carpal tunnel release (either endoscopic carpal tunnel release [ECTR] or open carpal tunnel release [OCTR]) and OCTR with a Camitz procedure. One hundred thirty-six patients with absent preoperative APB-CMAP constituted the material of our study. The CTSI and APB-CMAP recoveries between the "ECTR/OCTR group" and the "Camitz group" were compared before surgery and at three, six, and 12 months after surgery. RESULTS: There were no statistically significant differences in recovery between the "ECTR/OCTR group" and the "Camitz group" according to the three scales of CTSI (symptom severity scale, functional state scale, and FS-2 item, buttoning clothes: an alternative test of thumb opposition) and the APB-CMAP. CONCLUSION: Carpal tunnel release procedures resulted in the useful recovery of thumb opposition without the need for Camitz, even if APB-CMAP did not fully recover. The action of the other synergistic muscles acting on the thumb and the sensory recovery may have contributed to the recovery of thumb opposition. The Camitz procedure also may be only rarely indicated for hands affected by severe CTS. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Examination of Conditions for External Quality Control in Identification of Microorganisms using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was approved for medical use in 2011 and is currently used as a rapid, accurate and lowcost technique for bacterial identification. External quality control for medical analysis is monitored using tests of the Japanese Association of Medical Technologists and Prefectural Association of Clinical Laboratory Technologists and through user surveys of reagent and equipment manufacturers. However, external quality control of bacterial typing using MS is not performed. Therefore, we examined procedures for evaluating quality control of bacterial typing using an identification reliability index at 38 facilities.

Examination of conditions for regular internal quality control in identification of microorganisms using MALDI-TOF MS.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was approved for medical use in 2011, and is currently used as a rapid, accurate and low-cost technique for bacterial identification. Microbiological testing and internal accuracy control in Japan are mainly implemented in accordance with the standards of the Clinical and Laboratory Standards Institute (CLSI). However, few facilities perform internal accuracy control of bacterial identification by MALDI-TOF MS. Therefore, we examined the procedures for internal accuracy control of bacterial identification using MALDI-TOF MS in daily work at clinical laboratories in the seven hospitals.

Detection of microbial genes in a single leukocyte by polymerase chain reaction following laser capture microdissection.

Although isolation and identification of bacteria in a clinical specimen constitute essential steps for the diagnosis of bacterial infection, positive results of the bacterial culture are not always attained, despite observing the bacteria by Gram staining. As bacteria phagocytosed by the leukocytes are considered as the causative agents of infectious diseases, this study aims to introduce a new approach for the collection of only bacteria phagocytosed by the neutrophils in an animal model using laser capture microdissection (LCM) followed by the DNA identification using polymerase chain reaction (PCR). We inoculated representative bacteria (Escherichia coli and Staphylococcus aureus) into the abdominal cavities of specific pathogen-free C57BL/6 J mice. After 6 h inoculation, we collected the fluid samples from the peritoneal cavities of mice and demonstrated peritonitis by the increase of neutrophils. Then, we smeared the neutrophils on the membrane slides and collected single-cell phagocytosing bacteria by LCM. The supernatant of the cell lysate was supplied for the PCR reaction to amplify the 16S rRNA gene, and we validated the DNA sequences specific for the inoculated bacteria. In addition, PCR using specific primers for E. coli and S. aureus identified each species of bacteria. Hence, this study suggests that the combination of LCM and PCR could be a novel approach to determine bacteria in infectious diseases. Nevertheless, further investigation is warranted to test various additional bacterial taxa to demonstrate the general applicability of this method to clinical samples.

Multi-step genomic dissection of a suspected intra-hospital Helicobacter cinaedi outbreak.

Helicobacter cinaedi is an emerging pathogen causing bacteraemia and cellulitis. Nosocomial transmission of this microbe has been described, but detailed molecular-epidemiological analyses have not been performed. Here, we describe the results of a multi-step genome-wide phylogenetic analysis of a suspected intra-hospital outbreak of H. cinaedi that occurred in a hospital in Japan. The outbreak was recognized by the infectious control team (ICT) of the hospital as a sudden increase in H. cinaedi bacteraemia. ICT defined this outbreak case based on 16S rRNA sequence data and epidemiological information, but were unable to determine the source and route of the infections. We therefore re-investigated this case using whole-genome sequencing (WGS). We first performed a species-wide analysis using publicly available genome sequences to understand the level of genomic diversity of this under-studied species. The clusters identified were then separately analysed using the genome sequence of a representative strain in each cluster as a reference. These analyses provided a high-level phylogenetic resolution of each cluster, identified a confident set of outbreak isolates, and discriminated them from other closely related but distinct clones, which were locally circulating and invaded the hospital during the same period. By considering the epidemiological data, possible strain transmission chains were inferred, which highlighted the role of asymptomatic carriers or environmental contamination. The emergence of a subclone with increased resistance to fluoroquinolones in the outbreak was also recognized. Our results demonstrate the impact of the use of a closely related genome as a reference to maximize the power of WGS.

Development of a simple and practical method of discrimination between Vibrio furnissii and V. fluvialis based on single-nucleotide polymorphisms of 16S rRNA genes observed in V. furnissii but not in V. fluvialis.

Vibrio furnissii and V. fluvialis are closely related, the discrimination of which by conventional biochemical assay remains a challenge. Investigation of the sequence of the 16S rRNA genes in a clinical isolate of V. furnissii by visual inspection of a sequencing electropherogram revealed two sites of single-nucleotide polymorphisms (SNPs; positions 460 A/G and 1261 A/G) in these genes. A test of 12 strains each of V. fluvialis and V. furnissii revealed these SNPs to be common in V. furnissii but not in V. fluvialis. Divergence of SNP frequency was observed among the strains of V. furnissii tested. Because the SNPs described in V. furnissii produce a difference in the target sequence of restriction enzymes, a combination of polymerase chain reaction (PCR) of the 16S rRNA genes using conventional primers and restriction fragment length polymorphism analysis using Eco RV and Eae I was shown to discriminate between V. fluvialis and V. furnissii. This method is simple and alleviates the need for expensive equipment or primer sets specific to these bacteria. Therefore, we believe that this method can be useful, alongside specific PCR and mass spectrometry, when there is a need to discriminate between V. fluvialis and V. furnissii.

Extraintestinal infection of Helicobacter cinaedi induced by oral administration to Balb/c mice.

Although Helicobacter cinaedi was initially considered an opportunistic pathogen in immunocompromised patients, it was later shown to also infect immunocompetent and healthy individuals. Sporadic bacteremia due to H. cinaedi has frequently been reported; however, whether the bacterium can be translocated after passage through the intestinal mucosa remains unclear. In the present study, a preclinical small animal model that faithfully reproduces H. cinaedi infection in humans was developed. Balb/c male mice were orally inoculated with a single dose of 6.8 × 107 CFU of a human clinical H. cinaedi strain. The organism persistently colonized the intestinal tract of the mice, particularly the cecum and colon, for at least 56 days, and the bacteria were excreted in the feces. Although inoculated bacteria were recovered from the spleen, liver, kidney, lung, bladder and mesenteric lymph nodes during the first 2 weeks of bacteremia, the organism was not isolated from these organs after 4 weeks, suggesting that complement- and antibody-mediated serum sensitivity account for the relatively low frequency of systemic infection. However, H. cinaedi was isolated from the biceps femoris, triceps branchii, latissimus dorsi, and trapezius muscles beyond 2 weeks after infection and after production of specific anti-H. cinaedi IgM and IgG antibodies. The present findings suggest that experimental infection of Balb/c mice with H. cinaedi may be a useful model for further studies of H. cinaedi pathogenesis, prophylaxis or therapeutic interventions in vivo.

The pathogenic potential of Helicobacter cinaedi isolated from non-human sources: adherence, invasion and translocation ability in polarized intestinal epithelial Caco-2 cells in vitro.

Helicobacter cinaedi infection has been recognized as an increasingly important emerging disease in humans. Infection with H. cinaedi causes bacteremia, cellulitis and enteritis. H. cinaedi has been isolated from non-human sources, including dogs, cats and rodents; however, it remains unclear whether animal strains are pathogenic in humans and as zoonotic pathogens. In this study, H. cinaedi isolates were recovered from a dog and a hamster, and the ability of these isolates to adhere to, invade and translocate across polarized human intestinal epithelial Caco-2 cells was examined in vitro. To better understand the pathogenic potential of animal H. cinaedi isolates, these results were compared with those for a human strain that was isolated from a patient with bacteremia. The animal and human strains adhered to and invaded Caco-2 cells, but to a lesser degree than the C. jejuni 81-176 strain, which was used as a control. The integrity of tight junctions was monitored by measuring transepithelial electrical resistance (TER) with a membrane insert system. The TER values for all H. cinaedi strains did not change during the experimental periods compared with those of the controls; however, translocation of H. cinaedi from the apical side to the basolateral side was confirmed by cultivation and H. cinaedi-specific PCR, suggesting that the H. cinaedi strains translocated by transcellular route. This study demonstrated that H. cinaedi strains of animal origin might have a pathogenic potential in human epithelial cells as observed in a translocation assay in vitro with a human isolate.

Rapid identification and subtyping of Helicobacter cinaedi strains by intact-cell mass spectrometry profiling with the use of matrix-assisted laser desorption ionization-time of flight mass spectrometry.

Helicobacter cinaedi infection is recognized as an increasingly important emerging disease in humans. Although H. cinaedi-like strains have been isolated from a variety of animals, it is difficult to identify particular isolates due to their unusual phenotypic profiles and the limited number of biochemical tests for detecting helicobacters. Moreover, analyses of the 16S rRNA gene sequences are also limited due to the high levels of similarity among closely related helicobacters. This study was conducted to evaluate intact-cell mass spectrometry (ICMS) profiling using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as a tool for the identification of H. cinaedi. A total of 68 strains of H. cinaedi isolated from humans, dogs, a cat, and hamsters were examined in addition to other Helicobacter species. The major ICMS profiles of H. cinaedi were identical and differed from those of Helicobacter bilis, which show >98% sequence similarity at the 16S rRNA sequence level. A phyloproteomic analysis of the H. cinaedi strains examined in this work revealed that human isolates formed a single cluster that was distinct from that of the animal isolates, with the exception of two strains from dogs. These phyloproteomic results agreed with those of the phylogenetic analysis based on the nucleotide sequences of the hsp60 gene. Because they formed a distinct cluster in both analyses, our data suggest that animal strains may not be a major source of infection in humans. In conclusion, the ICMS profiles obtained using a MALDI-TOF MS approach may be useful for the identification and subtyping of H. cinaedi.

Obturator nerve injury associated with femur fracture fixation detected during gracilis muscle harvesting for functioning free muscle transfer.

A rare case is reported in which injury of the motor nerve of the gracilis (obturator nerve) was detected during its harvesting for functioning free muscle transfer. The probable cause of this rare injury was considered to be accidental penetration while drilling for a proximal locking screw in intramedullary nailing during previous femur fracture surgery.