Thoracic Outlet Syndrome Caused by a Primary Tumour in the Brachial Plexus.

Thoracic outlet syndrome (TOS) caused by a primary brachial plexus tumour is very rare. A male politician in his 40s presented with numbness, left limb pain and positive Wright and Roos test results. Magnetic resonance imaging (MRI) revealed a tumour located just below the clavicle, compressing the subclavian artery during left arm elevation. Despite concerns regarding postoperative nerve deficits, surgery was performed because of worsening symptoms during the election campaigns. The pathology report revealed a schwannoma. Few reports have described TOS caused by primary tumours of the brachial plexus. While the decision to perform surgery for primary tumours of the brachial plexus requires careful consideration, surgery may be indicated in cases where the tumour location causes such symptoms. Level of Evidence: Level V (Therapeutic).

Evaluation of Restricted Motion Area of the Median Nerve in Patients with Carpal Tunnel Syndrome: A New Measurement Method Using an Ultrasonographic Video Image.

Background: The precise etiology of carpal tunnel syndrome (CTS) remains unclear. One of the accepted factors for CTS is the restriction of the median nerve. Previous reports using ultrasound had only observed and measured the movement of parts of the median nerve. In this study, we aimed to elucidate the difference in the movement of the entire median nerve in patients with CTS (before and after surgery) and healthy volunteers using a new measurement method. Methods: We expressed the amount of movement of the entire nerve by a new method creating the motion area of the median nerve (MAMn) from an ultrasonographic video image on the computer. We compared the MAMn, the real MAMn (RMMn) (the value obtained by subtracting the nerve cross-sectional area from the MAMn), and mobile ratio (MR) (the value obtained from dividing the MAMn by the nerve cross-sectional area) between six wrists of six cases of CTS (before and at an average of 3.5 months after surgery) and six wrists of six healthy volunteers. Results: During passive wrist flexion, the average MAMn, RMMn, and MR of healthy cases were 23.1 mm2, 16.4 mm2, and 3.52, respectively. The average MAMn, RMMn, and MR of cases of CTS were respectively 11.8 mm2, 5.4 mm2, and 1.86 preoperatively; and 16.2 mm2, 7.3 mm2, and 1.87, postoperatively. The MAMn, RMMn, and MR decreased more significantly in patients with CTS than in healthy volunteers (p < 0.01). The MAMn and RMMn increased postoperatively (p < 0.05), but the MR remained low. Conclusions: The new measurement method revealed that the mobility of the entire median nerve was significantly restricted in cases of CTS compared to healthy participants. However, after surgery, nerve restriction was not restored despite improvements in symptoms, suggesting that decreases in nerve mobility contribute to CTS but are not a direct cause of symptoms.

Isolated Axillary Nerve Rupture due to Closed Nondislocating Injury of the Shoulder in Contact Sports: A Report of 2 Cases.

CASE: Axillary nerve rupture without shoulder joint fracture or dislocation in contact sports is very rare. To date, there has been no detailed report on such cases. We present 2 rare cases of axillary nerve rupture in contact sports who were successfully treated with free nerve grafting. CONCLUSION: In contact sports, the deltoid muscle is sometimes paralyzed temporarily after a collision. However, similar to our cases, the axillary nerve can be lacerated without fracture or dislocation. It is necessary to watch the course of paralysis carefully and consider nerve reconstruction if it does not recover.

The Tenosynovitis of Fingers Associated with Transthyretin Amyloidosis.

Background: Amyloidosis treatment has advanced rapidly along with the discovery of drugs to prevent amyloid deposition. Therefore, it is vital to detect amyloidosis at an early stage. Wild-type transthyretin, which can cause carpal tunnel syndrome, may also cause finger tenosynovitis. However, the correlation between wild-type transthyretin amyloid and finger tenosynovitis is unclear. Here, we investigated pathological and clinical findings for 20 patients with finger tenosynovitis who underwent operation at our hospital to determine the frequency of transthyretin amyloid deposition in idiopathic finger tenosynovitis. Methods: To check for the presence of amyloid deposition, all specimens (tendon synovium tissue or flexor tendon sheath) resected during the operation were stained by the direct fast scarlet method. Amyloid-positive specimens were evaluated by immunohistochemical staining using an anti-transthyretin antibody. Patient characteristics were evaluated with respect to amyloid presence. Results: Thirteen (65%) of 20 finger tenosynovitis cases had amyloid deposition. Nine (69.2%) of the 13 amyloid-positive cases exhibited extensive transthyretin staining and were considered to have transthyretin amyloid. Amyloid deposition was more frequent in men. The mean number of fingers with tenosynovitis was significantly higher in amyloid-positive cases (3.8 fingers) than in amyloid-negative cases (2.0 fingers). Conclusions: Men with multiple finger tenosynovitis tended to have transthyretin amyloid deposition. Our results support that multiple finger tenosynovitis may serve as an initial indication of evaluation for transthyretin amyloidosis.

Optimized Dosing Schedule Based on Circadian Dynamics of Mouse Breast Cancer Stem Cells Improves the Antitumor Effects of Aldehyde Dehydrogenase Inhibitor.

Although malignant phenotypes of triple-negative breast cancer (TNBC) are subject to circadian alterations, the role of cancer stem cells (CSC) in defining this circadian change remains unclear. CSC are often characterized by high aldehyde dehydrogenase (ALDH) activity, which is associated with the malignancy of cancer cells and is used for identification and isolation of CSC. Here, we show that the population of ALDH-positive cells in a mouse 4T1 breast tumor model exhibits pronounced circadian alterations. Alterations in the number of ALDH-positive cells were generated by time-dependent increases and decreases in the expression of Aldh3a1 Importantly, circadian clock genes were rhythmically expressed in ALDH-negative cells, but not in ALDH-positive cells. Circadian expression of Aldh3a1 in ALDH-positive cells was dependent on the time-dependent release of Wingless-type mmtv integration site family 10a (WNT10a) from ALDH-negative cells. Furthermore, antitumor and antimetastatic effects of ALDH inhibitor N,N-diethylaminobenzaldehyde were enhanced by administration at the time of day when ALDH activity was increased in 4T1 tumor cells. Our findings reveal a new role for the circadian clock within the tumor microenvironment in regulating the circadian dynamics of CSC. These results should enable the development of novel therapeutic strategies for treatment of TNBC with ALDH inhibitors.Significance: This seminal report reveals that circadian dynamics of CSC are regulated by the tumor microenvironment and provides a proof of principle of its implication for chronotherapy in TNBC. Cancer Res; 78(13); 3698-708. ©2018 AACR.

Circadian Clock in a Mouse Colon Tumor Regulates Intracellular Iron Levels to Promote Tumor Progression.

Iron is an important biological catalyst and is critical for DNA synthesis during cell proliferation. Cellular iron uptake is enhanced in tumor cells to support increased DNA synthesis. Circadian variations in DNA synthesis and proliferation have been identified in tumor cells, but their relationship with intracellular iron levels is unclear. In this study, we identified a 24-h rhythm in iron regulatory protein 2 (IRP2) levels in colon-26 tumors implanted in mice. Our findings suggest that IRP2 regulates the 24-h rhythm of transferrin receptor 1 (Tfr1) mRNA expression post-transcriptionally, by binding to RNA stem-loop structures known as iron-response elements. We also found thatIrp2mRNA transcription is promoted by circadian clock genes, including brain and muscle Arnt-like 1 (BMAL1) and the circadian locomotor output cycles kaput (CLOCK) heterodimer. Moreover, growth in colon-26(Δ19) tumors expressing the clock-mutant protein (CLOCK(Δ19)) was low compared with that in wild-type colon-26 tumor. The time-dependent variation of cellular iron levels, and the proliferation rate in wild-type colon-26 tumor was decreased by CLOCK(Δ19)expression. Our findings suggest that circadian organization contributes to tumor cell proliferation by regulating iron metabolism in the tumor.

Impact of phrenic nerve paralysis on the surgical outcome of intercostal nerve transfer.

Brachial plexus injuries (BPI) can be complicated by diaphragmatic paralysis (DP). This study determined the influence of DP on biceps brachii (BB) recovery after intercostal nerve transfer (ICNT) for BPI and investigated the respiratory complications of ICNT. The study included 100 patients, 84 showing no DP in preoperative and early postoperative chest radiographic images (non-DP group) and 16 with DP that persisted for over one year after surgery (DP group). The postoperative reinnervation time did not differ between groups. BB strength one year after surgery was lower in the DP group than non-DP group (p = 0.0007). No differences were observed 2-3 years after surgery. In the DP group, four patients had respiratory symptoms that affected daily activities and their outcomes deteriorated (p = 0.04). Phrenic nerve transfer should not be combined with ICNT in patients with poor respiratory function because of the high incidence of respiratory complications.

A comparison of muscle strength testing for great toe extension.

BACKGROUND: Although extensor hallucis longus (EHL) strength has been identified as a primary predictor of L5 nerve root radiculopathy and deep peroneal nerve palsy, assessment of EHL strength is commonly overlooked. This is mainly due to the lack of an objective and accurate method for evaluation, since manual muscle testing (MMT) has not been well utilized. A study of the reliability of evaluating MMT in various toe positions was performed. METHODS: To determine the reliability and validity of MMT for great toe extension, 40 normal volunteers (80 toes) with good muscle strength were recruited. Each subject was examined with MMT at the MTP joint (MTPp) and IP joint with various positions of the MTP joint (maximal extension: IPp-e, neutral position: IPp-n, maximal flexion: IPp-f) by two examiners. Inter-observer reproducibility was calculated for each MMT by κ values. Correlations between the great toe length and great toe extensor strength in each position, and between the angle in maximal extension of the MTP and great toe extensor strength in each position were examined using Spearman's correlation test. RESULTS: Great toe extensor strength was highly maintained in MTP measurement. Correct detections in each position (MTPp, IPp-e, IPp-n, IPp-f) were 96.3 and 96.3; 45.0 and 32.5%; 53.8 and 33.8%; and 50.0 and 61.5% for the first and second observer, respectively. The inter-observer variability for great toe extensor strength was highly maintained in MTP measurement (κ values = 1.00). The κ value of each position was 0.69, 0.35, and 0.28 for IPp-e, IPp-n, and IPp-f, respectively. There were no correlations between great toe length or angle in extension of the MTP and great toe extensor strength in each position. CONCLUSION: This study demonstrated that MTPp was much superior to the IP joint in the MMT procedure for great toe extension.