Tai-Chang Chern

Ultrasonography for diagnosing carpal tunnel syndrome: a meta-analysis of diagnostic test accuracy

Ultrasonography is widely used to diagnose carpal tunnel syndrome (CTS), a common peripheral neuropathy, but the reported diagnostic accuracy varies. This meta-analysis focused on the diagnostic test accuracy of ultrasonography for diagnosing CTS. Structured searches of PubMed for 1990-2010 were done and the data were extracted and meta-analyzed by pooling estimates of sensitivity, specificity, likelihood ratios and diagnostic odds ratios. Diagnostic performance was also judged by using a summary receiver operating characteristic curve. Twenty-eight trials involving 3995 wrists were included. A greater cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet (CSA-I) and a greater flattening ratio at the level of the hamate were seen in CTS wrists than in control wrists. A CSA-I ≥9 mm(2) is the best single diagnostic criterion, with a diagnostic odds ratio of 40.4 (sensitivity 87.3%, specificity 83.3%).

An Ultrasonographic and Anatomical Study of Carpal Tunnel, with Special Emphasis on the Safe Zones in Percutaneous Release

We examined 40 wrists of 12 embalmed and eight fresh cadavers and defined the relative position of the flexor retinaculum to the neurovascular structure, ultrasonographic markers and safe zones by ultrasonography and anatomical dissection. Both longitudinal and transverse ultrasonographic sections clearly depicted the flexor retinaculum, neurovascular bundles, median nerve, flexor tendons and bony boundaries of the underlying joints. Topographic measurement showed [i] good correlation between the actual extent of the flexor retinaculum and the ultrasonographically determined distance between bony landmarks in all hands, and [ii] the widths and lengths of well-defined safe zones. A comparison study confirmed the accuracy of ultrasonography. We conclude that these ultrasonographic landmarks can locate the flexor retinaculum and facilitate safe and complete carpal tunnel release with open or minimally invasive techniques.

A Cadaveric and Preliminary Clinical Study of Ultrasonographically Assisted Percutaneous Carpal Tunnel Release

The aim of this study was to assess the effectiveness and safety profile of a new technique for ultrasonographically assisted percutaneous carpal tunnel release. Experiments were performed on 40 hands in 20 cadavers. We first performed a detailed ultrasonographic examination and correlation study that included surgical dissection of the transverse carpal ligament, the related neurovascular structures and the bony landmarks of the radiocarpal, midcarpal and carpometacarpal joints of the right hand. We then used the measurements we made for percutaneous carpal tunnel release of the transverse carpal ligament using intra-operative ultrasonography for guidance and a hook knife on the left-hand side. The completeness of the release and the potential risks of injury to the flexor tendon and neurovascular bundles were examined. Using real-time intra-operative ultrasonographic monitoring to clearly delineate these targets, we were able to percutaneously release the transverse carpal ligament completely in 18 (90%) of the 20 hands and partially release it in 2 without injuring any neurovascular bundles. We then performed the procedure on 91 consecutive cases of carpal tunnel syndrome and found that the sensory disturbances disappeared in 100% patients 12 mo post-operatively; only 2 hands were graded as unsatisfactory. There were no intra- or post-operative complications. Based on the results from the cadaveric studies and our successful preliminary clinical outcomes, we conclude that this method is tolerable and that its clinical application can be encouraged.

A compound heterozygous mutation of CYP27A1 gene in a Taiwanese patient with cerebrotendinous xanthomatosis

Abstract Cerebrotendinous xanthomatosis (CTX, OMIM: 213700) is a rare inherited autosomal recessive lipid storage disorder with multiple system involvement. The disease is caused by mutations in the gene encoding sterol 27-hydroxylase (CYP27A1), leading to a block in bile synthesis, with accumulation of substrates for this enzyme, including cholesterol, resulting in an increase in the conversion of cholesterol to cholestanol. Clinically, CTX is characterized by tendon xanthomas, juvenile cataracts, premature atherosclerosis, and progressive neurological deficits [1]. We report the mutation analysis of a Taiwanese patient with CTX involving only the Achilles tendon.

Synovial osteochondromatosis of the second metatarsophalangeal joint: a case report.

Synovial osteochondromatosis is usually monoarticular, involving a large joint. Common locations include the knee, elbow, shoulder, and hip. It is not very common in the ankle, and it is very rare in the smaller joints of the foot. To our knowledge, and with the exception of 4 cases that occurred in the great toe, this condition has never been described in other metatarsophalangeal joints. In this report, we presented a case of synovial osteochondromatosis in the second metatarsophalangeal joint and reviewed the literature.

Sonographically Assisted Percutaneous Removal of Screws in Dynamization of the Interlocking Intramedullary Nail

Dynamization is a method of removing the interlocking screw(s) farthest from the fracture site for improving healing in femoral and tibial fractures that show delayed healing after static interlocking nailing. We describe a simple sonographically assisted technique for percutaneous dynamization of deep‐seated impalpable screws.

Synovial fluid biomarkers: association with chronic rotator cuff tear severity and pain

BACKGROUND We tested the hypothesis that biomarkers in the synovial fluid of the glenohumeral (shoulder) joint are correlated with visual analog scale (VAS) scores, functional scores, and ultrasound findings of chronic rotator cuff tear (RCT) severity. METHODS We measured biomarkers in shoulder joint synovial fluid of 42 patients with partial-thickness (21), nonmassive full-thickness (10), and massive full-thickness (11) RCTs. Pain duration, tear severity, and VAS and functional scores were compared with interleukin (IL) 1β, IL-6, matrix metalloproteinase (MMP) 1, and MMP-13 levels. RESULTS Both MMP-1 and MMP-13 levels were significantly highest in the massive full-thickness group. MMP-13 levels were significantly different between groups, but proinflammatory cytokine IL-1β and IL-6 levels were not. However, IL-1β levels were significantly positively correlated with VAS (r = 0.66; P <.01) and functional scores (r = 0.61; P <.01), but IL-6, MMP-1, and MMP-13 levels were not. CONCLUSIONS IL-1β levels in shoulder synovial fluid correlated positively with shoulder pain and functional scores in patients with chronic RCTs. Both MMP-1 and MMP-13 levels were altered and increased with cuff tear severity.