<?xml version="1.0" encoding="us-ascii"?>
<!-- Created by Merrill Corporation -->
<!-- Generated by Fujitsu Interstage XWand B0160 -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrldt="http://xbrl.org/2005/xbrldt">
  <link:roleRef roleURI="http://www.aastrom.com/role/BalanceSheet" xlink:type="simple" xlink:href="astm-20111231.xsd#BalanceSheet" />
  <link:roleRef roleURI="http://www.aastrom.com/role/StatementOfIncome" xlink:type="simple" xlink:href="astm-20111231.xsd#StatementOfIncome" />
  <link:roleRef roleURI="http://www.aastrom.com/role/CashFlows" xlink:type="simple" xlink:href="astm-20111231.xsd#CashFlows" />
  <link:roleRef roleURI="http://www.aastrom.com/role/StatementOfStockholdersEquity" xlink:type="simple" xlink:href="astm-20111231.xsd#StatementOfStockholdersEquity" />
  <link:calculationLink xlink:type="extended" xlink:role="http://www.aastrom.com/role/BalanceSheet">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_Assets" xlink:label="Assets" xlink:title="Assets" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="AssetsCurrent" xlink:title="AssetsCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="Assets" xlink:to="AssetsCurrent" xlink:title="calculation: Assets to AssetsCurrent" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="CashAndCashEquivalentsAtCarryingValue" xlink:title="CashAndCashEquivalentsAtCarryingValue" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="CashAndCashEquivalentsAtCarryingValue" xlink:title="calculation: AssetsCurrent to CashAndCashEquivalentsAtCarryingValue" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="ReceivablesNetCurrent" xlink:title="ReceivablesNetCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="ReceivablesNetCurrent" xlink:title="calculation: AssetsCurrent to ReceivablesNetCurrent" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OtherAssetsCurrent" xlink:label="OtherAssetsCurrent" xlink:title="OtherAssetsCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="OtherAssetsCurrent" xlink:title="calculation: AssetsCurrent to OtherAssetsCurrent" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="PropertyPlantAndEquipmentNet" xlink:title="PropertyPlantAndEquipmentNet" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="Assets" xlink:to="PropertyPlantAndEquipmentNet" xlink:title="calculation: Assets to PropertyPlantAndEquipmentNet" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="LiabilitiesAndStockholdersEquity" xlink:title="LiabilitiesAndStockholdersEquity" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="LiabilitiesCurrent" xlink:title="LiabilitiesCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="LiabilitiesCurrent" xlink:title="calculation: LiabilitiesAndStockholdersEquity to LiabilitiesCurrent" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:title="AccountsPayableAndAccruedLiabilitiesCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesCurrent" xlink:to="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:title="calculation: LiabilitiesCurrent to AccountsPayableAndAccruedLiabilitiesCurrent" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AccruedEmployeeBenefitsCurrent" xlink:label="AccruedEmployeeBenefitsCurrent" xlink:title="AccruedEmployeeBenefitsCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesCurrent" xlink:to="AccruedEmployeeBenefitsCurrent" xlink:title="calculation: LiabilitiesCurrent to AccruedEmployeeBenefitsCurrent" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="LongTermDebtCurrent" xlink:title="LongTermDebtCurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesCurrent" xlink:to="LongTermDebtCurrent" xlink:title="calculation: LiabilitiesCurrent to LongTermDebtCurrent" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_WarrantsAndRightsOutstanding" xlink:label="WarrantsAndRightsOutstanding" xlink:title="WarrantsAndRightsOutstanding" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesCurrent" xlink:to="WarrantsAndRightsOutstanding" xlink:title="calculation: LiabilitiesCurrent to WarrantsAndRightsOutstanding" order="4.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="LongTermDebtNoncurrent" xlink:title="LongTermDebtNoncurrent" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="LongTermDebtNoncurrent" xlink:title="calculation: LiabilitiesAndStockholdersEquity to LongTermDebtNoncurrent" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="StockholdersEquity" xlink:title="StockholdersEquity" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="StockholdersEquity" xlink:title="calculation: LiabilitiesAndStockholdersEquity to StockholdersEquity" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_CommonStockValue" xlink:label="CommonStockValue" xlink:title="CommonStockValue" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="CommonStockValue" xlink:title="calculation: StockholdersEquity to CommonStockValue" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="RetainedEarningsAccumulatedDeficit" xlink:title="RetainedEarningsAccumulatedDeficit" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="RetainedEarningsAccumulatedDeficit" xlink:title="calculation: StockholdersEquity to RetainedEarningsAccumulatedDeficit" order="2.0" weight="1.0" />
  </link:calculationLink>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.aastrom.com/role/StatementOfIncome">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="NetIncomeLossAvailableToCommonStockholdersBasic" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="OperatingIncomeLoss" xlink:title="OperatingIncomeLoss" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:to="OperatingIncomeLoss" xlink:title="calculation: NetIncomeLossAvailableToCommonStockholdersBasic to OperatingIncomeLoss" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_SalesRevenueNet" xlink:label="SalesRevenueNet" xlink:title="SalesRevenueNet" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="OperatingIncomeLoss" xlink:to="SalesRevenueNet" xlink:title="calculation: OperatingIncomeLoss to SalesRevenueNet" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_SalesRevenueGoodsNet" xlink:label="SalesRevenueGoodsNet" xlink:title="SalesRevenueGoodsNet" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="SalesRevenueNet" xlink:to="SalesRevenueGoodsNet" xlink:title="calculation: SalesRevenueNet to SalesRevenueGoodsNet" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_ResearchAndDevelopmentAgreements" xlink:label="ResearchAndDevelopmentAgreements" xlink:title="ResearchAndDevelopmentAgreements" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="SalesRevenueNet" xlink:to="ResearchAndDevelopmentAgreements" xlink:title="calculation: SalesRevenueNet to ResearchAndDevelopmentAgreements" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_RevenueFromGrants" xlink:label="RevenueFromGrants" xlink:title="RevenueFromGrants" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="SalesRevenueNet" xlink:to="RevenueFromGrants" xlink:title="calculation: SalesRevenueNet to RevenueFromGrants" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_CostsAndExpenses" xlink:label="CostsAndExpenses" xlink:title="CostsAndExpenses" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="OperatingIncomeLoss" xlink:to="CostsAndExpenses" xlink:title="calculation: OperatingIncomeLoss to CostsAndExpenses" order="2.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_CostOfGoodsSold" xlink:label="CostOfGoodsSold" xlink:title="CostOfGoodsSold" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="CostsAndExpenses" xlink:to="CostOfGoodsSold" xlink:title="calculation: CostsAndExpenses to CostOfGoodsSold" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="ResearchAndDevelopmentExpense" xlink:title="ResearchAndDevelopmentExpense" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="CostsAndExpenses" xlink:to="ResearchAndDevelopmentExpense" xlink:title="calculation: CostsAndExpenses to ResearchAndDevelopmentExpense" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="SellingGeneralAndAdministrativeExpense" xlink:title="SellingGeneralAndAdministrativeExpense" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="CostsAndExpenses" xlink:to="SellingGeneralAndAdministrativeExpense" xlink:title="calculation: CostsAndExpenses to SellingGeneralAndAdministrativeExpense" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="NonoperatingIncomeExpense" xlink:title="NonoperatingIncomeExpense" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:to="NonoperatingIncomeExpense" xlink:title="calculation: NetIncomeLossAvailableToCommonStockholdersBasic to NonoperatingIncomeExpense" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_ChangesInFairValueOfWarrants" xlink:label="ChangesInFairValueOfWarrants" xlink:title="ChangesInFairValueOfWarrants" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NonoperatingIncomeExpense" xlink:to="ChangesInFairValueOfWarrants" xlink:title="calculation: NonoperatingIncomeExpense to ChangesInFairValueOfWarrants" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OtherNonoperatingIncome" xlink:label="OtherNonoperatingIncome" xlink:title="OtherNonoperatingIncome" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NonoperatingIncomeExpense" xlink:to="OtherNonoperatingIncome" xlink:title="calculation: NonoperatingIncomeExpense to OtherNonoperatingIncome" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_InvestmentIncomeInterest" xlink:label="InvestmentIncomeInterest" xlink:title="InvestmentIncomeInterest" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NonoperatingIncomeExpense" xlink:to="InvestmentIncomeInterest" xlink:title="calculation: NonoperatingIncomeExpense to InvestmentIncomeInterest" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_InterestExpense" xlink:label="InterestExpense" xlink:title="InterestExpense" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NonoperatingIncomeExpense" xlink:to="InterestExpense" xlink:title="calculation: NonoperatingIncomeExpense to InterestExpense" order="4.0" weight="-1.0" />
  </link:calculationLink>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.aastrom.com/role/CashFlows">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetCashProvidedByUsedInContinuingOperations" xlink:label="NetCashProvidedByUsedInContinuingOperations" xlink:title="NetCashProvidedByUsedInContinuingOperations" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:label="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:title="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInContinuingOperations" xlink:to="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:title="calculation: NetCashProvidedByUsedInContinuingOperations to NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="NetIncomeLossAvailableToCommonStockholdersBasic" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to NetIncomeLossAvailableToCommonStockholdersBasic" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="DepreciationDepletionAndAmortization" xlink:title="DepreciationDepletionAndAmortization" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="DepreciationDepletionAndAmortization" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to DepreciationDepletionAndAmortization" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="GainLossOnSaleOfPropertyPlantEquipment" xlink:title="GainLossOnSaleOfPropertyPlantEquipment" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="GainLossOnSaleOfPropertyPlantEquipment" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to GainLossOnSaleOfPropertyPlantEquipment" order="3.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:label="AmortizationOfFinancingCostsAndDiscounts" xlink:title="AmortizationOfFinancingCostsAndDiscounts" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="AmortizationOfFinancingCostsAndDiscounts" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to AmortizationOfFinancingCostsAndDiscounts" order="4.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="ShareBasedCompensation" xlink:title="ShareBasedCompensation" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="ShareBasedCompensation" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to ShareBasedCompensation" order="5.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_ChangesInFairValueOfWarrants" xlink:label="ChangesInFairValueOfWarrants" xlink:title="ChangesInFairValueOfWarrants" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="ChangesInFairValueOfWarrants" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to ChangesInFairValueOfWarrants" order="6.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_InventoryWriteDown" xlink:label="InventoryWriteDown" xlink:title="InventoryWriteDown" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="InventoryWriteDown" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to InventoryWriteDown" order="7.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_IssuanceOfStockAndWarrantsForServicesOrClaims" xlink:label="IssuanceOfStockAndWarrantsForServicesOrClaims" xlink:title="IssuanceOfStockAndWarrantsForServicesOrClaims" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="IssuanceOfStockAndWarrantsForServicesOrClaims" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to IssuanceOfStockAndWarrantsForServicesOrClaims" order="8.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="ProvisionForDoubtfulAccounts" xlink:title="ProvisionForDoubtfulAccounts" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="ProvisionForDoubtfulAccounts" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to ProvisionForDoubtfulAccounts" order="9.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_IncreaseDecreaseInReceivables" xlink:label="IncreaseDecreaseInReceivables" xlink:title="IncreaseDecreaseInReceivables" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="IncreaseDecreaseInReceivables" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to IncreaseDecreaseInReceivables" order="10.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="IncreaseDecreaseInInventories" xlink:title="IncreaseDecreaseInInventories" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="IncreaseDecreaseInInventories" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to IncreaseDecreaseInInventories" order="11.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_IncreaseDecreaseInOtherCurrentAssets" xlink:label="IncreaseDecreaseInOtherCurrentAssets" xlink:title="IncreaseDecreaseInOtherCurrentAssets" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="IncreaseDecreaseInOtherCurrentAssets" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to IncreaseDecreaseInOtherCurrentAssets" order="12.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:title="IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" order="13.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities" xlink:label="IncreaseDecreaseInEmployeeRelatedLiabilities" xlink:title="IncreaseDecreaseInEmployeeRelatedLiabilities" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="IncreaseDecreaseInEmployeeRelatedLiabilities" xlink:title="calculation: NetCashProvidedByUsedInOperatingActivitiesContinuingOperations to IncreaseDecreaseInEmployeeRelatedLiabilities" order="14.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:label="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:title="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInContinuingOperations" xlink:to="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:title="calculation: NetCashProvidedByUsedInContinuingOperations to NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_OrganizationalCostsActivity" xlink:label="OrganizationalCostsActivity" xlink:title="OrganizationalCostsActivity" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="OrganizationalCostsActivity" xlink:title="calculation: NetCashProvidedByUsedInInvestingActivitiesContinuingOperations to OrganizationalCostsActivity" order="1.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_PaymentsToAcquireShortTermInvestments" xlink:label="PaymentsToAcquireShortTermInvestments" xlink:title="PaymentsToAcquireShortTermInvestments" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="PaymentsToAcquireShortTermInvestments" xlink:title="calculation: NetCashProvidedByUsedInInvestingActivitiesContinuingOperations to PaymentsToAcquireShortTermInvestments" order="2.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments" xlink:label="ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments" xlink:title="ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments" xlink:title="calculation: NetCashProvidedByUsedInInvestingActivitiesContinuingOperations to ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="PaymentsToAcquirePropertyPlantAndEquipment" xlink:title="PaymentsToAcquirePropertyPlantAndEquipment" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="PaymentsToAcquirePropertyPlantAndEquipment" xlink:title="calculation: NetCashProvidedByUsedInInvestingActivitiesContinuingOperations to PaymentsToAcquirePropertyPlantAndEquipment" order="4.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:title="ProceedsFromSaleOfPropertyPlantAndEquipment" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:title="calculation: NetCashProvidedByUsedInInvestingActivitiesContinuingOperations to ProceedsFromSaleOfPropertyPlantAndEquipment" order="5.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:label="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:title="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInContinuingOperations" xlink:to="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:title="calculation: NetCashProvidedByUsedInContinuingOperations to NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromIssuanceOfPreferredStockAndPreferenceStock" xlink:label="ProceedsFromIssuanceOfPreferredStockAndPreferenceStock" xlink:title="ProceedsFromIssuanceOfPreferredStockAndPreferenceStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="ProceedsFromIssuanceOfPreferredStockAndPreferenceStock" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to ProceedsFromIssuanceOfPreferredStockAndPreferenceStock" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromIssuanceOrSaleOfEquity" xlink:label="ProceedsFromIssuanceOrSaleOfEquity" xlink:title="ProceedsFromIssuanceOrSaleOfEquity" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="ProceedsFromIssuanceOrSaleOfEquity" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to ProceedsFromIssuanceOrSaleOfEquity" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromIssuanceOfWarrants" xlink:label="ProceedsFromIssuanceOfWarrants" xlink:title="ProceedsFromIssuanceOfWarrants" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="ProceedsFromIssuanceOfWarrants" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to ProceedsFromIssuanceOfWarrants" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromRepaymentsOfRestrictedCashFinancingActivities" xlink:label="ProceedsFromRepaymentsOfRestrictedCashFinancingActivities" xlink:title="ProceedsFromRepaymentsOfRestrictedCashFinancingActivities" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="ProceedsFromRepaymentsOfRestrictedCashFinancingActivities" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to ProceedsFromRepaymentsOfRestrictedCashFinancingActivities" order="4.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:label="ProceedsFromIssuanceOfLongTermDebt" xlink:title="ProceedsFromIssuanceOfLongTermDebt" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="ProceedsFromIssuanceOfLongTermDebt" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to ProceedsFromIssuanceOfLongTermDebt" order="5.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_RepaymentsOfLongTermDebt" xlink:label="RepaymentsOfLongTermDebt" xlink:title="RepaymentsOfLongTermDebt" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="RepaymentsOfLongTermDebt" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to RepaymentsOfLongTermDebt" order="6.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities" xlink:label="ProceedsFromPaymentsForOtherFinancingActivities" xlink:title="ProceedsFromPaymentsForOtherFinancingActivities" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="ProceedsFromPaymentsForOtherFinancingActivities" xlink:title="calculation: NetCashProvidedByUsedInFinancingActivitiesContinuingOperations to ProceedsFromPaymentsForOtherFinancingActivities" order="7.0" weight="1.0" />
  </link:calculationLink>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.aastrom.com/role/StatementOfStockholdersEquity">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockholdersEquityPeriodIncreaseDecrease" xlink:label="StockholdersEquityPeriodIncreaseDecrease" xlink:title="StockholdersEquityPeriodIncreaseDecrease" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="NetIncomeLossAvailableToCommonStockholdersBasic" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to NetIncomeLossAvailableToCommonStockholdersBasic" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodValueCommonStockForCashServicesAndLicenseRights" xlink:label="StockIssuedDuringPeriodValueCommonStockForCashServicesAndLicenseRights" xlink:title="StockIssuedDuringPeriodValueCommonStockForCashServicesAndLicenseRights" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueCommonStockForCashServicesAndLicenseRights" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueCommonStockForCashServicesAndLicenseRights" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodValueSeriesAPreferredStock" xlink:label="StockIssuedDuringPeriodValueSeriesAPreferredStock" xlink:title="StockIssuedDuringPeriodValueSeriesAPreferredStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueSeriesAPreferredStock" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueSeriesAPreferredStock" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodValueSeriesEPreferredStock" xlink:label="StockIssuedDuringPeriodValueSeriesEPreferredStock" xlink:title="StockIssuedDuringPeriodValueSeriesEPreferredStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueSeriesEPreferredStock" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueSeriesEPreferredStock" order="4.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="StockIssuedDuringPeriodValueShareBasedCompensation" xlink:title="StockIssuedDuringPeriodValueShareBasedCompensation" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueShareBasedCompensation" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueShareBasedCompensation" order="5.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:label="AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:title="AdjustmentsToAdditionalPaidInCapitalWarrantIssued" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to AdjustmentsToAdditionalPaidInCapitalWarrantIssued" order="6.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_AdjustmentsToAdditionalPaidInCapitalPaymentReceivedUnderShareholderNoteReceivable" xlink:label="AdjustmentsToAdditionalPaidInCapitalPaymentReceivedUnderShareholderNoteReceivable" xlink:title="AdjustmentsToAdditionalPaidInCapitalPaymentReceivedUnderShareholderNoteReceivable" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="AdjustmentsToAdditionalPaidInCapitalPaymentReceivedUnderShareholderNoteReceivable" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to AdjustmentsToAdditionalPaidInCapitalPaymentReceivedUnderShareholderNoteReceivable" order="7.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="StockIssuedDuringPeriodValueNewIssues" xlink:title="StockIssuedDuringPeriodValueNewIssues" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueNewIssues" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueNewIssues" order="8.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:label="StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:title="StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" order="9.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:title="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" order="10.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodValueConvertiblePreferredStock" xlink:label="StockIssuedDuringPeriodValueConvertiblePreferredStock" xlink:title="StockIssuedDuringPeriodValueConvertiblePreferredStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueConvertiblePreferredStock" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueConvertiblePreferredStock" order="11.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodValueCommonStock" xlink:label="StockIssuedDuringPeriodValueCommonStock" xlink:title="StockIssuedDuringPeriodValueCommonStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueCommonStock" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueCommonStock" order="12.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:label="StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:title="StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" order="13.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:label="StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:title="StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" order="14.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueStockDividend" xlink:label="StockIssuedDuringPeriodValueStockDividend" xlink:title="StockIssuedDuringPeriodValueStockDividend" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodValueStockDividend" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodValueStockDividend" order="15.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xlink:label="StockRepurchasedAndRetiredDuringPeriodValue" xlink:title="StockRepurchasedAndRetiredDuringPeriodValue" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockRepurchasedAndRetiredDuringPeriodValue" xlink:title="calculation: StockholdersEquityPeriodIncreaseDecrease to StockRepurchasedAndRetiredDuringPeriodValue" order="16.0" weight="-1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:label="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:title="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodSharesCommonStockForCashServicesAndLicenseRights" xlink:label="StockIssuedDuringPeriodSharesCommonStockForCashServicesAndLicenseRights" xlink:title="StockIssuedDuringPeriodSharesCommonStockForCashServicesAndLicenseRights" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesCommonStockForCashServicesAndLicenseRights" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesCommonStockForCashServicesAndLicenseRights" order="1.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodSharesSeriesAPreferredStock" xlink:label="StockIssuedDuringPeriodSharesSeriesAPreferredStock" xlink:title="StockIssuedDuringPeriodSharesSeriesAPreferredStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesSeriesAPreferredStock" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesSeriesAPreferredStock" order="2.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodSharesSeriesEPreferredStock" xlink:label="StockIssuedDuringPeriodSharesSeriesEPreferredStock" xlink:title="StockIssuedDuringPeriodSharesSeriesEPreferredStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesSeriesEPreferredStock" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesSeriesEPreferredStock" order="3.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:title="StockIssuedDuringPeriodSharesShareBasedCompensation" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesShareBasedCompensation" order="4.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="StockIssuedDuringPeriodSharesNewIssues" xlink:title="StockIssuedDuringPeriodSharesNewIssues" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesNewIssues" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesNewIssues" order="5.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:title="StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" order="6.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodSharesConvertiblePreferredStock" xlink:label="StockIssuedDuringPeriodSharesConvertiblePreferredStock" xlink:title="StockIssuedDuringPeriodSharesConvertiblePreferredStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesConvertiblePreferredStock" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesConvertiblePreferredStock" order="7.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="astm-20111231.xsd#astm_StockIssuedDuringPeriodSharesCommonStock" xlink:label="StockIssuedDuringPeriodSharesCommonStock" xlink:title="StockIssuedDuringPeriodSharesCommonStock" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesCommonStock" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesCommonStock" order="8.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:label="StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:title="StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" order="9.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:label="StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:title="StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" order="10.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_PreferredStockDividendsShares" xlink:label="PreferredStockDividendsShares" xlink:title="PreferredStockDividendsShares" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="PreferredStockDividendsShares" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to PreferredStockDividendsShares" order="11.0" weight="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xlink:label="StockRepurchasedAndRetiredDuringPeriodShares" xlink:title="StockRepurchasedAndRetiredDuringPeriodShares" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:to="StockRepurchasedAndRetiredDuringPeriodShares" xlink:title="calculation: StockIssuedDuringPeriodSharesPeriodIncreaseDecrease to StockRepurchasedAndRetiredDuringPeriodShares" order="12.0" weight="1.0" />
  </link:calculationLink>
</link:linkbase>
