## 4 Discussion
### Study Limitations  
A key limitation of this study is the low number of cadavers used for validating the implants. Each implant is tested only on one hand. Future work will use more cadavers to validate the implant's mechanical efficacy at whole-hand grasp task strength and stability. Additionally, more live animal validation and regulatory work are required before moving to our first in-human trials.  
Conceptualization, S.C.R., K.J., F.J.V.-C. and R.B.; methodology, S.C.R., W.S.Y., K.J., J.C.C., V.R.H., F.J.V.-C. and R.B.; software, S.C.R. and K.J.; validation, S.C.R., W.S.Y., K.J., J.C.C., N.R.L.-M., V.R.H., F.J.V.-C. and R.B.; formal analysis, S.C.R., F.J.V.-C. and R.B.; investigation, S.C.R., W.S.Y., K.J., N.R.L.-M., V.R.H., F.J.V.-C. and R.B.; resources, S.C.R., W.S.Y., F.J.V.-C. and R.B.; data curation, S.C.R., W.S.Y. and F.J.V.-C.; writing--original draft preparation, S.C.R., W.S.Y., K.J., J.C.C., N.R.L.-M., V.R.H., F.J.V.-C. and R.B.; writing--review and editing, S.C.R., W.S.Y., K.J., J.C.C., N.R.L.-M., V.R.H., F.J.V.-C. and R.B.; visualization, S.C.R. and R.B.; supervision, F.J.V.-C. and R.B.; project administration, S.C.R., F.J.V.-C. and R.B.; funding acquisition, S.C.R., F.J.V.-C. and R.B. All authors have read and agreed to the published version of the manuscript.  
This work was partially funded by the US Department of Defense Congressionally Directed Medical Research Program grant number MRI50091 awarded to [PERSON] and [PERSON], National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health grant numbers R01-AR050520 and R01-AR052345, National Institute of Neurological Diseases and Stroke grant number R21-NS113613 and Defense Advanced Research Project Agency L2M grant number W911 NF1820264, and National Science Foundation awarded CRCNS US-Japan Award number 2113096 to [PERSON]. Additionally, some work in this manuscript was partly funded by National Science Foundation CAREER award number 1554739 to [PERSON]. Finally, this work was also partially funded by the University of Southern California Graduate School's Research Enhancement Fellowship awarded to [PERSON].  
The data collected during this study and the code used to process it are available on reasonable requests made to the corresponding author.  
The authors thank [PERSON] and [PERSON] for assisting us with the setup of the cadaver studies, [PERSON] for assisting us with the preparation of the fresh-frozen human cadaver specimens, [PERSON] for helping set up motion-capture and robotic dry-run tests, [PERSON] for illustrating our setup Figures 3 and 4, and [PERSON] and [PERSON] for volunteering his time to proofread the manuscript. The authors express their gratitude to the Hand Biomechanics Lab for their donation of the Agee-WristJacks(r).  
**Conflicts of Interest**: The research conducted in this work relies on patented designs for the passive mechanisms implanted between the FDP tendons and the ECRL muscle (U.S. Patents 9,925,035 and 10,595,984) granted to [PERSON] and [PERSON] along with [PERSON]. [PERSON] and [PERSON] hold equity in OrthoMechanica, Inc. that seeks to commercialize the developed implants. Hand Biomechanics Lab contributed some of the equipment--Agee-WristJacks(r) and bone pins--used in this study.