Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Hanger (NYSE: HGR), a provider of orthotic and prosthetic patient care services, tumbled as much as 11% after the company reported disappointing first-quarter results after the closing bell last night.

So what: For the quarter, Hanger reported an increase in revenue of 2.7% to $235.6 million as a 3.5% increase in its patient care segment more than offset a small sales decline in its product and services segment. Adjusted earnings, however, dipped to $0.19 per share from $0.27 per share in the year-ago period. Hanger, like many of its earnings report predecessors, blamed the tough winter and a difficult reimbursement environment for its challenging results. By comparison, Wall Street had expected Hanger to deliver $0.25 in adjusted EPS on $243.6 million in revenue.

Looking ahead, the company's full-year guidance also failed to impress. Hanger anticipates reporting full-year revenue of $1.1 billion-$1.12 billion, in-line with current expectations for $1.12 billion, but just $2.01-$2.11 in EPS, which is below the $2.16 that the Street was projecting.

Now what: The good news for Hanger, if there is a bright side to its earnings report, is that the weather is largely unpredictable and not a cause for investor concern. Its reimbursement worries, however, could extend for some time as the Centers for Medicare and Medicaid Services has made it quite clear that it plans to reduce government-sponsored reimbursements over the long term. This is going to make growth for companies like Hanger difficult to come by in the interim. Although Hanger isn't particularly expensive at 13 times forward earnings, I'm having a tough time seeing where its growth and catalysts are going to come from. As such, I believe it's a stock I'd be perfectly happy monitoring from the sidelines.