Table 5.

FMEA/FMECA of the pre-bioprinting phase and cell preparation sub-phase.

Step	Activity	Failure Mode	Potential Cause	Possible Consequences	O	S	D	RPN	Mitigation Actions
MSC selection type	Clinical need evaluation/Source choice	Inappropriate cell type selection	Inadequate cell response	Impaired chondroprotective cell potential	5	8	8	320	Definition of new selection criteria
MSC culture	Cell isolation	Microbial contamination Cell death/low cell growth Non-idoneous cell number/passage Impaired cell phenotype	Human error, low instrument performance Improper culture conditions Sample variability	No adequate cell availability to continue the process Delay in experimental plan	4	10	2	80	Periodic instrument controls (calibration) Optimization of culture conditions Definition of strict criteria for sample processing Personnel training
	Cell characterization	Microbial contamination Cell death/low cell growth Non-idoneous cell number/passage Impaired cell phenotype	Human error, low instrument performance Improper culture conditions Sample variability	No adequate cell availability to continue the process Delay in experimental plan	5	9	2	90	Periodic instrument controls (calibration) Optimization of culture conditions Definition of stricter criteria for sample processing Personnel training
MSC culture	Cell expansion	Microbial contamination Cell death/low cell growth Non-idoneous cell number/passage Impaired cell phenotype	Human error, low instrument performance Improper culture conditions Sample variability	No adequate cell availability to continue the process Delay in experimental plan	8	6	2	96	Periodic instrument controls (calibration) Optimization of culture conditions Definition of stricter criteria for sample processing Personnel training
MSC suspension preparation	Cell harvest	Low cell growth	Human error Improper culture conditions Sample variability	Lower than planned yield A high amount of cell death Delay in the experimental plan	4	6	2	48	Optimization of culture conditions Definition of more stringent criteria for sample processing Personnel training
	Cell characterization	Impaired cell phenotype/function	Improper culture conditions	Wrong/non-idoneous cell population	6	9	2	108	Periodic instrument controls (calibration) Optimization of culture conditions Optimization of culture conditions
	Medium definition for cell suspension	Impaired cell viability	Improper culture conditions	High cell death during post-printing phase	6	10	6	360	Optimization of culture medium for cell suspension