What happened

Spine surgery solutions specialist NuVasive (NASDAQ:NUVA) outpaced the market last month by gaining 18% compared to a 3% spike in the S&P 500, according to data provided by S&P Global Market Intelligence.

The rally put shareholders back into positive territory for the year, with the stock up 17% in the past 12 months compared to a 2% gain in the broader market.

A surgeon in the operating room.

Image source: Getty Images.

So what

Investors were happy with the fourth-quarter earnings results NuVasive published late in the month that showed sales rising 6% as net income improved to $36 million, or $0.69 per share, from $29 million, or $0.56 per share a year earlier. Its surgical support division was the company's fastest-growing segment, but the spinal hardware unit pulled those gains lower due to an overall weak selling environment.

Now what

Management's outlook for the 2019 fiscal year predicts only modest sales growth, but continued market share gains assuming a flat industry for spinal surgery solutions. NuVasive plans to make targeted investments in advancing strategic initiatives including its implant systems and surgical solutions platform.

Balancing those needs with cost discipline should deliver non-GAAP operating profit of between 15% and 15.5% of sales, executives said, up slightly from the past year's 15.1% result.