NuVasive Inc. posted third-quarter sales of $94.9 million, up 41.8 percent over the $66.9 million the San Diego-based firm posted during the same period last year.

NuVasive, which is developing what it calls “minimally disruptive” spine surgery techniques, said its net income for the three months ended Sept. 30 rose to $5.1 million, compared with a net loss of $23.1 million during the third quarter of 2008.

Much of that increase can be chalked up to reduced operating expenses. NuVasive slashed its sales, marketing and administrative expenses as a share of revenues by nearly 19 percent and cut total operating expenses by nearly 42 percent.

The company raised its full-year guidance, predicting revenues of $365 million to $367 million, up from a previous forecast of $360 million to $365 million for 2009.

Earnings per share also got a boost, to $0.11-$0.14, compared with the $0.06-$0.08 from the previous guidance.