Research Focus

　

Peripheral Nerve Injury

　

Clinical Assessment of Common Tests for Traumatic injury or pathologic change of shoulder joint

　

Electrophysiological markers & hypothermia

　

　

　

　

　

　

Peripheral Nerve Injury

　

1.     Intrafascicular electrode and peripheral nerve signal

　

2.  Novel Biodegradable Regeneration-Type Neural Interfaces for High-Resolution Stimulation and Recording from Peripheral Nerves

 

　

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Intrafascicular electrode and peripheral nerve signal

 

1. We aim to study long-term recording of nerve signal by modified intrafascicular electrodes in rabbits. Methods for long-term recording of peripheral nerve activity via intrafascicular electrodes have not been optimized. Intrafascicular electrodes with a spring-like structure demonstrated superior potential for long-term electrophysiologic monitoring over straight electrodes.

　

　

2. The residual motor pathways after amputation have not been fully elucidated. We sampled potentials from peripheral nerve stumps with intrafascicular electrodes to study residual motor transmission and explore the feasibility of nerve signal-controlled artificial limbs. The long-term amputee was able to generate motor neuron activity related to phantom limb movement. Intrafascicular electrodes can be used to monitor residual motor nerve activity in the stump and the amplitude may predict successful control of artificial limbs.

　

　

    

　

Figure (Left) Two intrafascicular electrodes surgically implanted in the radial nerve, (right) The original position of the Neural signal-controlled prosthesis and finger extension of the Nerve-signal Controlled Prosthesis Simulation Instrument was triggered during the operation by volitional control from the amputee

　

　

Publication

  1. Xiaofeng Jia, Jong Hun Ji, Steve Peterson, Jennifer Keefer, Edward G McFarland. Clinical Evaluation of the Shoulder Shrug Sign. Clin Orthop Relat Res,  2008 DOI 10.1007/s11999-008-0331-3

  2. Xiaofeng Jia, Gehua Zhen, Adrian Puttgen, Jian Zhang, Tongyi Chen. Improved long-term recording of nerve signal by modified intrafascicular electrodes in rabbits. Microsurgery 2008 28(3) 173-178

  3. Xiaofeng Jia, Gehua Zhen, Matthew A Koenig, Jian Zhang, Tongyi Chen, Zhongwei Chen. Long-term biocompatibility of intrafascicular electrodes in rabbit sciatic nerve. The 75th Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS), San Francisco, California, March 5-9, 2008

  4. Xiaofeng Jia, Tongyi Chen, Matthew A Koenig, Jian Zhang, Xiaowen Zhang, Yupu Yang, Tianpei Hu, and Zhongwei Chen. Feasibility of signal-controlled artificial limbs: Residual motor signal in peripheral nerve stumps. Platform session at The 74th Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS), Feb 14-18, 2007 San Diego, CA, USA. The Proceedings of 74th Annual Meeting of the American Academy of Orthopaedic Surgeons. Pp 545

  5. Tianpei Hu, Xiaowen Zhang, Zhonghua Zhang, Jian Zhang, Xiaofeng Jia, Xiujun Zheng, Yupu Yang, Zhongwei Chen, Xiaoming Xu, Tongyi Chen. Initial detection and analysis of neuro-information from amputee. Sheng Wu Yi Xue Gong Cheng Xue Za Zhi, 2006 Feb; 23(1):1-5

  6. Xiao-Wen ZHANG, Zhong-Hua GAO, Tian-Pei HU, Yu-Pu YANG, Xiao-Ming XU, Jian ZHANG, Xiao-Feng JIA, Xiu-Jun ZHENG, Zhong-Wei CHEN, Tong-Yi CHEN. Research on Prosthesis Controlled by Neuro-information. CHINESE JOURNAL OF BIOMEDICAL ENGINEERING, 2005 24 (5):624-628

  7. Xiaofeng Jia, Zhongwei Chen, Jian Zhang, Tongyi Chen and Yihao Zhu. The experimental study on harvesting information of sensory nerve with intrafascicular electrodes. Chinese Journal of Practical Medicine, 2004; 4(13): 1153-1155

  8. Xiaofeng Jia, Zhongwei Chen, Tongyi Chen, Jian Zhang, Xiaowen Zhang, Yang Si and Tianpei Hu. Harvesting the signals of nerves in the remaining limb of human by intrafascicular microelectrodes. Chinese Journal of Microsurgery, 2004; 27(1): 24-26

  9. Xiaofeng Jia, Tongyi Chen, Zhongwei Chen, Jian Zhang, Xiaowen Zhang, Yang Si Tianpei Hu, Zhonghua Gao and Yupu Yang. The original report of the first experimental study on electric prosthesis controlled by signals of nerves in amputation stump of human. Chinese Journal of Physical Medicine and Rehabilitation, 2004; 26 (1):  20-23

  10. Xiaofeng Jia, Zhongwei Chen, Tongyi Chen, Jian Zhang, Xiaowen Zhang, Yang Si and Tianpei Hu. Experimental study on harvesting nerve-signals in the human amputation stump of the upper arm. Chinese Journal of Orthopedic Trauma, 2003; 5 (3): 165-167

  11. Xiaofeng Jia, Zhongwei Chen, Jian Zhang, Tongyi Chen, Yihao Zhu and Rong Han. The application of modified intrafascicular electrodes in recording the electric signal of sciatic nerve of rabbits. Shanghai Medical Journal, 2003; 26 (4): 243-245

  12. Xiaofeng Jia, Jian Zhang, Zhongwei Chen, Zhongwei Chen, Yihao Zhu, Rong Han and Zhiying Qiu. Experimental study on harvesting the electric signal of peripheral nerve at rabbits by intrafascicular microelectrodes. Chinese Journal of Hand Surgery, 2002; 18 (4): 245-247

  13. Xiaofeng Jia, Zhongwei Chen, Tongyi Chen, Jian Zhang, Xiujun Zheng, Yihao Zhu, Rong Han and Zhiying Qiu. The real-time signal recording of sciatic nerve of rabbits after acute implantation of self-made intrafascicular electrode. Proceedings of National Medicine and Public Health Excellent Products, 2002 Nov 24; 320-322

  14. Xiaofeng Jia, Zhongwei Chen, Tongyi Chen, Jian Zhang, Xiujun Zheng, Yihao Zhu, Rong Han and Zhiying Qiu. The real-time signal recording of sciatic nerve of rabbits after acute implantation of self-made intrafascicular electrode. Chinese Journal of Clinical Rehabilitation, 2002; 6 (22): 3366-3367, Figure page 22-3

  15. Xiaofeng Jia, Tongyi Chen and Zhongwei Chen. Classification and recognition of electric signal with intrafascicular electrode. Chinese Journal of Clinical Rehabilitation, 2002; 6 (2): 220-221, 243

  16. Xiaowen Zhang, Tianpei Hu, Zhonghua Gao, Yupu Yang, Xiaoming Xu, Jian Zhang, Xiujun Zheng, Xiaofeng Jia, Zhongwei Chen and Tongyi Chen. Initial Detection and Analysis on Neuro-information from Amputee. The 11th World Congress of the International Society for Prosthetics and Orthotics, p49. Aug 1-6, 2004 Hong Kong

  17. Xiaofeng Jia, Jian Zhang, Tongyi Chen, Zhongwei Chen, Yihao Zhu, Rong Han and Zhiying Qiu. Experimental study on the signal recording of sciatic nerve of rabbits with intrafascicular electrodes. Proceedings of International Symposium on Rehabilitation engineering and Clinical Rehabilitation, p288-291. Aug 26-31 2002 Dalian, China 

　

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Novel Biodegradable Regeneration-Type Neural Interfaces for High-Resolution Stimulation and Recording from Peripheral Nerves

　

We aim to develop novel, high site-count microelectrodes that are optimized for electrically stimulating and recording from regenerated peripheral nerves.  These devices will facilitate the creation of next-generation neuroprosthetic systems for restoring function to upper- and lower-limb amputees.

　

(Left) Chemical structure of desaminotyrosyl-tyrosine alkyl esters derived polycabonate, abbreviated ‘poly(DTR carbonate)’. The carboxylic acid terminal group is protected by an alkyl ester which can be regarded as a pendent chain. The structure of the alkyl esters is indicated by the following nomenclature convention: DT, desaminotyrosyl-tyrosine ester; DTE, desaminotyrosyl-tyrosine ethyl ester; DTB, desaminotyrosyl-tyrosine butyl ester; DTH, desaminotyrosyl-tyrosine hexyl ester; DTO, desaminotyrosyl-tyrosine octyl ester; DTD, desaminotyrosyl tyrosine dodecyl ester. These particular monomers are most commonly used in the synthesis of tyrosine-derived polymers (Right) Porous scaffold fabricated from poly (DTE carbonate) with a bimodal distribution of macro- and micro-pores. Macropores (212–425 mm) are the impressions of the salts, the micropores (about 1 to 10 mm) are caused by the formation of frozen solvent crystals during cooling (Bourke & Kohn, 2003).

 

　

Main researchers

Xiaofeng Jia, MD, Ph.D, Youngseok Choi, Ph.D, Xiaoxu Kang, B.S. ,Xing Wang, M.S.

　

Collaborators

Dan Lewitus, PhD, Vogelstein, R. Jacob, PhD, Carlos A. Pardo, M.D.

　

Funding

Defense Advanced Project and Research Agency (DARPA)

 

　

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Clinical Assessment of Common Tests for Traumatic injury or pathologic change of shoulder joint

　

To assess the clinical usefulness of various physical examination tests as tools for the diagnosis, tests were performed during the physical examination to make a diagnosis of traumatic injury or pathologic change of shoulder joint and prospectively entered into a database at the Division of Sports Medicine and Shoulder Surgery, Department of Orthopaedic Surgery, Johns Hopkins University, and then was evaluated with statistical methods to determine the clinical value (overall accuracy, sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratios, and the post-test probabilities).

　

Main researchers

Xiaofeng Jia, MD, Ph.D, Jong Hun Ji, Steve Peterson, Edward G. McFarland M.D.

　

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