Shares in

Hanger Orthopedic Group

(HGR)

surged Monday ahead of its second-quarter earnings report, which the company abruptly postponed last week.

Last Monday, Hanger delayed its postmarket close report by a week to "complete certain accounting reviews."

Shares today jumped 97 cents, or 22%, to $5.39 in trading volume approaching twice the daily average of 393,000 shares. The stock went from $9.54 last Monday to $4.42 at the end of last week on the heels of the announcement.

The Bethesda, Md.-based company last Monday said the "accounting matters have no relation to the allegations of billing discrepancies at the patient care center in West Hempstead, N.Y., and preliminary findings of the independent investigation are being announced in a separate news release."

The billing discrepancies first became public in June when

WNBC-TV

in New York reported that the company was "facing investigation for allegedly stealing from Medicare, Medicaid and insurance companies." The report, paraphrasing a Hanger employee, said "thousands of patient files are forged or nonexistent."

Hanger, at the time, said it has "been made aware of alleged billing irregularities" by an employee at one of its 608 medical outlets and "in conjunction with its outside counsel, has initiated a prompt and thorough investigation of these allegations."

The company later said it had been subpoenaed by federal prosecutors in New York and also received a request for information from the

Securities and Exchange Commission

.

Since then, shareholders have filed lawsuits against the company, alleging it artificially inflated the price of its stock through fraudulent actions.

Analysts expect the company to earn 34 cents a share.

Hanger describes itself as "the world's premier provider of orthotic and prosthetic patient-care services." It has operations in 44 states and the District of Columbia, with 3,115 employees.