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      <link:roleType id="WarrantsTables" roleURI="http://si-bone.com/role/WarrantsTables">
        <link:definition>2308301 - Disclosure - Warrants (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
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  <xsd:element abstract="true" id="sibn_A2018EmployeeStockPurchasePlanMember" name="A2018EmployeeStockPurchasePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_A2018EquityIncentivePlanMember" name="A2018EquityIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_AdjustmentstoAdditionalPaidinCapitalSharebasedCompensationVestingOfEarlyExercisedStockOptions" name="AdjustmentstoAdditionalPaidinCapitalSharebasedCompensationVestingOfEarlyExercisedStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_AvailableForSaleDebtSecuritiesCurrentAccumulatedGrossUnrealizedGainBeforeTax" name="AvailableForSaleDebtSecuritiesCurrentAccumulatedGrossUnrealizedGainBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="sibn_AvailableForSaleDebtSecuritiesCurrentAccumulatedGrossUnrealizedLossBeforeTax" name="AvailableForSaleDebtSecuritiesCurrentAccumulatedGrossUnrealizedLossBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_AvailableForSaleDebtSecuritiesCurrentAmortizedCostBasis" name="AvailableForSaleDebtSecuritiesCurrentAmortizedCostBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_AvailableForSaleDebtSecuritiesNoncurrentAccumulatedGrossUnrealizedGainBeforeTax" name="AvailableForSaleDebtSecuritiesNoncurrentAccumulatedGrossUnrealizedGainBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="sibn_AvailableForSaleDebtSecuritiesNoncurrentAccumulatedGrossUnrealizedLossBeforeTax" name="AvailableForSaleDebtSecuritiesNoncurrentAccumulatedGrossUnrealizedLossBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_AvailableForSaleDebtSecuritiesNoncurrentAmortizedCostBasis" name="AvailableForSaleDebtSecuritiesNoncurrentAmortizedCostBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_ClassOfWarrantOrRightNumberOfWarrantsOrRightsConverted" name="ClassOfWarrantOrRightNumberOfWarrantsOrRightsConverted" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_CommonStockWarrantsMember" name="CommonStockWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_ComputerAndOfficeEquipmentMember" name="ComputerAndOfficeEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_DebtInstrumentClosingFeePercentage" name="DebtInstrumentClosingFeePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="sibn_DebtInstrumentCovenantMinimumCashBalance" name="DebtInstrumentCovenantMinimumCashBalance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_DebtInstrumentPeriodicPaymentInterestOnlyPeriod" name="DebtInstrumentPeriodicPaymentInterestOnlyPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_DebtInstrumentPrepaymentPenaltyPercentage" name="DebtInstrumentPrepaymentPenaltyPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="sibn_DebtPrepaymentPenaltyPeriodAxis" name="DebtPrepaymentPenaltyPeriodAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_DebtPrepaymentPenaltyPeriodDomain" name="DebtPrepaymentPenaltyPeriodDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_DebtSecuritiesAvailableForSaleNoncurrentAbstract" name="DebtSecuritiesAvailableForSaleNoncurrentAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_DebtSecuritiesAvailableforsaleNoncurrentTerm" name="DebtSecuritiesAvailableforsaleNoncurrentTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_EmployeeStockPurchasePlanSharesMember" name="EmployeeStockPurchasePlanSharesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_LiabilityForEarlyExerciseOfOptionsCurrent" name="LiabilityForEarlyExerciseOfOptionsCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="sibn_MarketableSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" name="MarketableSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="sibn_MarketableSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" name="MarketableSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_MarketableSecuritiesAmortizedCost" name="MarketableSecuritiesAmortizedCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="sibn_MarketableSecuritiesFairValue" name="MarketableSecuritiesFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="sibn_PharmakonTermLoanMember" name="PharmakonTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PrepaymentPenalty3148MonthsMember" name="PrepaymentPenalty3148MonthsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PrepaymentPenalty4960MonthsMember" name="PrepaymentPenalty4960MonthsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_RedeemableConvertiblePreferredStockWarrantsMember" name="RedeemableConvertiblePreferredStockWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_SantaClaraCaliforniaMember" name="SantaClaraCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsEarlyExerciseCommonStockSubjectToRepurchase" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsEarlyExerciseCommonStockSubjectToRepurchase" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="sibn_ShareSubjectToRepurchaseMember" name="ShareSubjectToRepurchaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_SharebasedCompensationArrangementbySharebasedPaymentAwardAnnualIncreaseInSharesReservedAsPercentageOfPriorYearSharesOutstanding" name="SharebasedCompensationArrangementbySharebasedPaymentAwardAnnualIncreaseInSharesReservedAsPercentageOfPriorYearSharesOutstanding" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="sibn_StockIssuedDuringPeriodAmountRestrictedStockUnits" name="StockIssuedDuringPeriodAmountRestrictedStockUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodSharesIssuanceOfCommonStockUponExerciseOfUnvestedStockOptions" name="StockIssuedDuringPeriodSharesIssuanceOfCommonStockUponExerciseOfUnvestedStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodSharesRestrictedStockUnits" name="StockIssuedDuringPeriodSharesRestrictedStockUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodValueIssuanceOfCommonStockUponExerciseOfUnvestedStockOptions" name="StockIssuedDuringPeriodValueIssuanceOfCommonStockUponExerciseOfUnvestedStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_VestingOfEarlyExercisedStockOptions" name="VestingOfEarlyExercisedStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedDecemberTwentySecondTwentySixteenMember" name="WarrantsIssuedDecemberTwentySecondTwentySixteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedJulyNineteenthTwentyThirteenMember" name="WarrantsIssuedJulyNineteenthTwentyThirteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedMarchFirstTwentySeventeenMember" name="WarrantsIssuedMarchFirstTwentySeventeenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedNovemberNinthTwentyFifteenMember" name="WarrantsIssuedNovemberNinthTwentyFifteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedNovemberTwentySixthTwentyFourteenMember" name="WarrantsIssuedNovemberTwentySixthTwentyFourteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedOctoberTwentiethTwentyFifteenMember" name="WarrantsIssuedOctoberTwentiethTwentyFifteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsLiabilityMember" name="WarrantsLiabilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_WarrantsOutstandingFairValueOnDateOfIssuanceOrConversion" name="WarrantsOutstandingFairValueOnDateOfIssuanceOrConversion" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
</xsd:schema>