Revenue Recognition

Revenue is recognized when persuasive evidence of an arrangement exists, the price is fixed and determinable, delivery has occurred and there is a reasonable assurance of collection of the sales proceeds. Revenues for products are recognized when the tissue is delivered to the customer, at which time title passes to the customer. Once product is delivered, the Company has no further performance obligations. Delivery is defined as delivery to a customer location or segregation of product into a contracted distribution location. At such time, this product cannot be sold to any other customer. Fees charged to customers for storage and shipping of products are recognized as revenues when processed tissue is shipped to the customer or end user.

Cash and Cash Equivalents and Concentration

For purposes of the statement of cash flows, the Company considers all highly liquid debt instruments purchased with a maturity of three months or less to be cash equivalents. Cash and cash equivalents are maintained at financial institutions and, at times, balances may exceed federally insured limits. The Company has never experienced any losses related to these balances.

Accounts Receivable and Concentration of Credit Risk

Accounts receivable are carried at the original invoice amount less an estimate made for doubtful accounts based on a review of all outstanding amounts on a monthly basis. Management determines the allowance for doubtful accounts by regularly evaluating individual customer receivables and considering a customer’s financial condition, credit history and current economic conditions. Accounts receivable are written off when deemed uncollectible. Recoveries of accounts receivable previously written off are recorded when received. As of September 30, 2011 and December 31, 2010, there were no amounts deemed uncollectible and there was no allowance for doubtful accounts recorded.

Concentrations of credit risk with respect to accounts receivable are limited because a large number of geographically diverse customers make up the Company’s customer base, thus spreading the trade credit risk. The Company also controls credit risk through credit approvals, credit limits and monitoring procedures.

Inventories

Inventories are comprised of implantable tissue, nerve grafts, AXOGuard ^® Nerve Connector, AXOGuard^® Nerve Protector, and supplies that are valued at the lower of cost (first-in, first-out) or market and consist of the following:

Property and Equipment

Depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets as follows:

Major additions and improvements are capitalized, while replacements, maintenance and repairs, which do not improve or extend the life of the respective assets, are expensed as incurred. When assets are retired or otherwise disposed of, related costs and accumulated depreciation and amortization are removed and any gain or loss is reported as other income or expense.

Intangible Assets

Intangible assets consist primarily of license agreements for exclusive rights to use various patented and patent-pending technologies described in Note 6 and other costs related to the license agreements, including patent prosecution and protection costs. Such costs are capitalized and amortized on a straight-line basis over the underlying terms of the license agreements or estimated useful life of patents, ranging from 5 to 20 years.

Goodwill

Goodwill represents the excess of the purchase price over the fair value of net assets acquired. No impairment has been recognized during the nine months ended September 30, 2011 and 2010.

Impairment of Long-lived Assets, Including License Agreements

The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future undiscounted cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. No impairment has been recognized for the nine months ended September 30, 2011 and 2010.

Deferred Financing Costs

The Company capitalizes all third-party costs incurred, including equity-based payments, associated with the issuance of long-term debt. The costs are amortized to interest expense over the term of the debt using the effective interest method.

Advertising

Advertising costs are expensed as incurred. Advertising costs were approximately $9,118 and $1,228 for the three months ended September 30, 2011 and 2010 and $10,758 and $5,789 for the nine months ended September 30, 2011 and 2010, respectively, and are included in sales and marketing expense on the accompanying consolidated statements of operations.

Research and Development Costs

Research and Development costs are expensed as incurred.

Income Taxes

The Company has not recorded current income tax expense due to the generation of net operating losses. Deferred income taxes are accounted for using the balance sheet approach which requires recognition of deferred tax assets and liabilities for the expected future consequences of temporary differences between the financial reporting basis and the tax basis of assets and liabilities. A valuation allowance is provided when it is more likely than not that a deferred tax asset will not be realized. A full valuation allowance has been established on the deferred tax asset as it is more likely than not that future tax benefit will not be realized. In addition, future utilization of the available net operating loss carryforward may be limited under Internal Revenue Code Section 382 as a result of changes in ownership.

The Company identifies and evaluates uncertain tax positions, if any, and recognizes the impact of uncertain tax positions for which there is a less than more-likely-than-not probability of the position being upheld when reviewed by the relevant taxing authority. Such positions are deemed to be unrecognized tax benefits and a corresponding liability is established on the balance sheet. The Company has not recognized a liability for uncertain tax positions. If there were an unrecognized tax benefit, the Company would recognize interest accrued related to unrecognized tax benefits in interest expense and penalties in operating expenses. The Company’s remaining open tax years subject to examination by the Internal Revenue Service include the years ended December 31, 2007 through 2010.

Preferred Stock

The Company accounts for its preferred stock under the provisions of Accounting Standards Codification on Distinguishing Liabilities from Equity, which sets forth the standards for how an issuer classifies and measures certain financial instruments with characteristics of both liabilities and equity. This standard requires an issuer to classify a financial instrument that is within the scope of the standard as a liability or temporary equity if such financial instrument embodies an unconditional obligation to redeem the instrument at a specified date and/or upon an event certain to occur.

All or any number of the Series B, Series C, and Series D preferred stock may become redeemable by a majority of preferred shareholder approval at any time after January 7, 2015 at a redemption price determined in accordance with the Company’s Certificate of Incorporation, plus accrued and unpaid dividends. The Company has determined that its Series B, Series C, and Series D preferred stock requires temporary equity classification as its obligation to redeem these instruments are outside the control of the Company. Permanent equity classification is not currently applicable as the preferred stock is not currently redeemable but may become so in the future.

Derivative Financial Instruments

The Company accounts for derivative instruments in accordance with Accounting Standards Codification on Derivatives and Hedging, which requires additional disclosures about the Company’s objectives and strategies for using derivative instruments, how the derivative instruments and related hedging items are accounted for, and how the derivative instruments and related hedging items affect the financial statements. The Company does not use derivative instruments to hedge exposures to cash flow, market or foreign currency risk. Terms of convertible debt and equity instruments are reviewed to determine whether or not they contain embedded derivative instruments that are required to be accounted for separately from the host contract, and recorded on the balance sheet at fair value. The fair value of derivative liabilities, including freestanding warrants, is required to be revalued at each reporting date, with corresponding changes in fair value recorded in current period operating results. An evaluation of specifically identified conditions is made to determine whether the fair value of warrants issued is required to be classified as equity or as a derivative liability.

Fair Value of Financial Instruments

The respective carrying value of certain on-balance-sheet financial instruments approximated their fair values due to the short-term nature of these instruments. These financial instruments include cash, accounts receivable, accounts payable and accrued expenses. The fair value of the Company’s long-term debt approximates its carrying value based upon current rates available to the Company.

Stock-Based Compensation

Stock-based compensation cost related to stock options granted under the AC 2002 Stock Option Plan (the “Plan”—see Note 10) is measured at grant date, based on the fair value of the award, and is recognized as an expense over the employee’s requisite service period. The Company estimates the fair value of each option award issued under the Plan on the date of grant using a Black-Scholes option-pricing model that uses the assumptions noted in the table below. The Company estimates the volatility of its common stock at the date of grant based on the volatility of comparable peer companies which are publicly traded. The Company determines the expected life based on historical experience with similar awards, giving consideration to the contractual terms, vesting schedules and post-vesting forfeitures. The Company uses the risk-free interest rate on the implied yield currently available on U.S. Treasury issues with an equivalent remaining term approximately equal to the expected life of the award. The Company has never paid any cash dividends on its common stock and does not anticipate paying any cash dividends in the foreseeable future. The Company used the following weighted-average assumptions for options granted during the nine months ended September 30:

The Company estimates forfeitures when recognizing compensation expense and this estimate of forfeitures is adjusted over the requisite service period based on the extent to which actual forfeitures differ, or are expected to differ, from such estimates. Changes in estimated forfeitures are recognized through a cumulative catch-up adjustment, which is recognized in the period of change, and also impact the amount of unamortized compensation expense to be recognized in future periods. The Company did not apply a forfeiture allocation to its unvested options outstanding during the nine months ended September 30, 2011 as they were deemed insignificant.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Recent Accounting Pronouncements

In September 2011, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2011-08, Intangibles — Goodwill and Other (Topic 350) - Testing Goodwill for Impairment. ASU 2011-8 is intended to simplify the testing of goodwill for impairment by permitting an entity to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test described in Topic 350. ASU 2011-08 will become effective for fiscal years beginning after December 15, 2011, with early adoption permitted in limited circumstances. The Company is assessing the impact of ASU 2011-08 on its goodwill impairment test but do not expect an impact on its financial condition or results of operations.

In December 2010, FASB issued ASU No. 2010-29, Business Combinations (Topic 805) — Disclosure of Supplementary Pro Forma Information for Business Combinations. If a public entity presents comparative financial statements, the entity should disclose revenue and earnings of the combined entity as though the business combination that occurred during the current year had occurred as of the beginning of the comparable prior annual reporting period only. ASU 2010-29 also expands the supplementary pro forma disclosures. ASU 2010-29 is effective prospectively for business combinations for which the acquisition date is on or after the beginning of the first annual reporting period beginning on or after December 15, 2010.