Current evidence on potential of adipose derived stem cells to enhance bone regeneration and future projection

Table 1 Summary of the clinical trials involving treatment of the bone defects using adipose-derived stem cells

Bone defect treated	Study duration and length of follow up	n	Intervention	ADSCs source	ADSCs number	Outcome	Ref.
Avascular necrosis of hip, osteoarthritis of hip/knee/ankle, spinal disc herniation	2009-2012, 30 mo	91	Intraarticular injection of SVF with PRP	Autologous SVF from abdominal tumescent liposuction	10 mL of SVF	No evidence of neoplasm, no serious adverse events, common adverse events (swelling of injected joints, tenosynovitis, and tendonitis) were either successfully managed or self-limited, established safety of ADSCs	Pak et al[29]
Upper arm fracture in elderly patients (62-84 yr)	2012-2014, 6 mo	8	SVF seeded porous silicated-hydroxyapatite microgranules with fibrin hydrogel implant	Autologous SVF from abdominal tumescent liposuction	800 microliters of SVF	Evidence of osteogenesis at graft site; circumstantial evidence for direct contribution of SVF cells to fracture healing	Saxer et al[30]
Large cranial defect	2008-2010, 12 mo	4	ADSCs-seeded β-tricalcium phosphate implant	Autologous ADSC from abdominal subcutaneous liposuction	15 × 106 cells	Noted equivalence between newly generated tissue and native bone	Thesleff et al[31]
Large cranial defect	2008-2016, approximately 7 yr	5	ADSCs-seeded β-tricalcium phosphate implant	Autologous ADSC from abdominal subcutaneous liposuction	15 × 106 cells	This study was long term follow up of Thesleff et al[31]; unsatisfactory long-term outcome with significant resorption	Thesleff et al[32]
Cranio-maxillofacial hard-tissue defects	2012-2014, up to 52 mo	13	ADSCs-seeded bioactive glass or β-tricalcium phosphate scaffolds, at times with recombinant hBMP-2	Autologous ADSC from anterior abdominal wall liposuction	Up to 160 × 106 cells	Majority of patients achieved satisfactory clinical and radiographic results; three experienced significant resorptions of the ADSCs graft	Sándor et al[33]
Long bone nonunion from bone tumor resection or pseudoarthrosis	2012-2014, 39 mo	6	ADSCs seeded decellularized bone matrix	Subcutaneous autologous ADSCs	Up to 200 × 106 cells	50% of the patients achieved bone regeneration and union	Dufrane et al[34]
Maxillary sinus floor elevation	2009-2015, 36 mo	10	SVF seeded β- tricalcium phosphate implant	Autologous SVF from abdominal tumescent lipo-aspiration	20 × 106 cells	Experimental group exhibited significantly more bone healing compared to control	Prins et al[35]
Alveolar cleft osteoplasty	2015-2016, 6 mo	10	Lateral ramus cortical bone plate with ADSCs-mounted natural bovine bone mineral	Autologous ADSCs from buccal fat pad	1.0 × 106	No significant different in bone regeneration found between experimental group and controls	Khojasteh et al[36]
Mandibular fracture	2010-2015, 12 wk	20	Direct application of ADSCs	Autologous ADSCs	Unreported	Significantly more osteogenesis in ADSCs-treated group compared to control	Castillo-Cardiel et al[37]
Nonunion following subtalar arthrodesis	2010-2016, 24 mo	140	ADSC-seeded partially demineralized bone matrix	Allograft ADSCs	Unreported	Inferior bone union rate in ADSCs treated group compared to autograft; equivalent clinical evaluations	Myerson et al[38]

ADSCs: Adipose-derived stem cells; SVF: Stromal Vascular Fraction; PRP: Platelet-rich plasma.