Unique skin findings in a case of the A3 pulley trigger finger due to an osteochondroma

Trigger finger is usually caused by stenosing tenosynovitis and hypertrophy of the retinacular sheath, and the most common site of tendon triggering is the A1 pulley. Although the A3 pulley trigger finger has been described in a few cases caused by hypertrophy of the retinacular sheath and ganglion, associated skin findings have not been reported to date. Herein, we report a rare case of the A3 pulley trigger finger due to osteochondroma with unique skin findings in a 50-year-old woman. In this case, we observed a V-shaped skin depression on the palmar side of the proximal interphalangeal joint of the right middle finger during finger locking. Additionally, we observed bilateral linear skin depressions on the sides of the proximal phalange. These findings might be caused by the traction force on the A3 pulley, connected to the skin via the Grayson and Cleland ligaments, which are fibrous tissues that connect the skin and tendon sheath.

Effect of Reveromycin A on experimental tooth movement in OPG-/- mice

In osteoprotegerin-deficient (OPG-/-) mice, osteoclast activity causes bone resorption to outpace bone formation, leading to the development of severe osteoporosis. Such mice are therefore useful for investigating the alveolar bone of patients with osteoporosis. Reveromycin A (RM-A) was recently identified as the unique agent acting on osteoclast activation. This study aimed to analyze the effect of RM-A on the orthodontic treatment of OPG-/- mice (a model of osteoporosis patients with high levels of bone turnover). We examined alveolar bone remodeling in OPG-/- and wild-type (WT) mice during continuous tooth movement. The orthodontic force was induced by means of a Ni-Ti closed-coil spring to move the maxillary first molar for 14 days. RM-A sodium salt (1 mg/kg) was administered intraperitoneally twice daily. In OPG-/- mice, the tooth movement distance was longer, alveolar bone resorption was enhanced, the osteoclast count was greater, and serum alkaline phosphatase and tartrate-resistant acid phosphatase levels were higher relative to those in WT mice. However, the administration of RM-A in OPG-/- mice reduced these parameters. We conclude that RM-A normalizes bone metabolism and loss of alveolar bone during continuous tooth movement in OPG-/- mice.

Effect of long-term physical exercise of peripheral nerve: comparison of nerve conduction study and ultrasonography

AIM

The aim of this study was to assess the effects of long-term physical exercise on peripheral nerve using both nerve conduction study (NCS) and ultrasonography (US).

METHODS

The authors measured nerve conduction study and ultrasonography in 15 male (mean, 20±1.5 years) handball players and 13 male (mean, 21.3±1.9 years) control subjects. Cross-sectional area of the median nerve was evaluated using ultrasonography at the carpal tunnel and 6 cm proximal to the wrist, and the ulnar nerve at 6 cm proximal to the wrist crease, 2 cm proximal to the medial epicondyle, the epicondyle, and 2 cm distal to epicondyle.

RESULTS

US shows significantly increased cross-sectional area of both median and ulnar nerve in the players compared with that in the controls, and the latency times in both nerves were significantly delayed in the players compared with that in the controls. Cross-sectional area of the median nerve showed a significant correlation with latency (r=0.330, P<0.01).

CONCLUSION

This study suggests that the players have a tendency toward having both median and ulnar motor nerve damage in the wrist or elbow region although they are asymptomatic.