Safety and Efficacy Study of Autologous Concentrated Bone Marrow Aspirate (cBMA) for Critical Limb Ischemia (CLI)

Inclusion Criteria: * Unilateral or bilateral lower extremity ischemia due to advanced peripheral arterial disease * Unsuitable for revascularization * Minor tissue loss (Rutherford Category 5) or ischemic rest pain (Rutherford Category 4) with ABI ≤ 0.6, or TBI ≤ 0.4, or TcPO2 ≤ 50 mm Hg * Competent to give consent * No current malignancy or history of previous malignancy within the last five years, with the exception of adequately treated non-melanoma skin cancer (evidence of standard preventative cancer screenings required) Exclusion Criteria: * Major tissue loss (Rutherford Category 6) * Diabetics on oral or insulin therapy with uncontrolled or untreated proliferative retinopathy (evidence of retinal exam required) * Poorly controlled diabetes mellitus with HbA1C \> 10% (evidence of HbA1C test required) * Uncompensated congestive heart failure (New York Heart Association Class IV) and/or other conditions that preclude general anesthesia * Myocardial infarction or stroke within last 90 days * Elevated liver function tests (AST or ALT more than twice normal upper limit) * Renal disease (creatinine \> 2.5 mg/dl) or chronic hemodialysis * White blood cell count \< 3,000/µL or \> 15,000/µL, platelet count \< 100,000/µL, or hematocrit \< 32% * Topical growth hormone therapy within last 90 days, or injected growth hormone therapy within last 180 days * Disease of central nervous system and/or other conditions that impair cognitive function * Two or more episodes of pulmonary embolus with a documented DVT in index leg or history of DVT in index leg without evidence of clot resolution * Current infection of index leg * Pregnant women (negative urine pregnancy test required) * Lower extremity venous disease with pitting edema in index leg * Recent history (in the 6 months prior to screening) of bone marrow disease or treatment with any medication or procedure which adversely affects the bone marrow and would prohibit transplantation * Current osteomyelitis in index leg * Existing HIV diagnosis * Organ transplant recipients * Known terminal disease process with life expectancy less than one year * Severe concomitant disease(s) or any additional condition(s) which the investigator feels constitute(s) criteria for exclusion of a particular subject * Major amputation required within 30 days * Inclusion in any other clinical study that may affect the outcome of this study * Uncorrected stenosis(es) of greater than 50% in the common and/or external iliac artery and/or common femoral artery of the index leg.