There's no bigger name in health care than Johnson & Johnson (JNJ 1.49%), and the company's justified its fame through a history of strong, stable performance. J&J did it again in the second quarter, as the company's adjusted earnings managed to top Wall Street's expectations, even as revenue came in a little short.

The firm's medical-device division performed surprisingly well, as sales picked up by 9.6% year over year. However, J&J's giant acquisition of orthopedics power Synthes last year has provided the spark to an otherwise lackluster segment in recent quarters. Is this device business really as strong as the company's earnings have shown? Motley Fool contributor Dan Carroll explains how J&J's medical devices have been performing -- and whether or not you should be cautious about this standout company's results.