To develop and apply an implanted neuroprosthesis to restore arm and hand function to individuals with high level tetraplegia.
Case study.
Clinical research laboratory.
Individuals with spinal cord ...injuries (N=2) at or above the C4 motor level.
The individuals were each implanted with 2 stimulators (24 stimulation channels and 4 myoelectric recording channels total). Stimulating electrodes were placed in the shoulder and arm, being, to our knowledge, the first long-term application of spiral nerve cuff electrodes to activate a human limb. Myoelectric recording electrodes were placed in the head and neck areas.
Successful installation and operation of the neuroprosthesis and electrode performance, range of motion, grasp strength, joint moments, and performance in activities of daily living.
The neuroprosthesis system was successfully implanted in both individuals. Spiral nerve cuff electrodes were placed around upper extremity nerves and activated the intended muscles. In both individuals, the neuroprosthesis has functioned properly for at least 2.5 years postimplant. Hand, wrist, forearm, elbow, and shoulder movements were achieved. A mobile arm support was needed to support the mass of the arm during functional activities. One individual was able to perform several activities of daily living with some limitations as a result of spasticity. The second individual was able to partially complete 2 activities of daily living.
Functional electrical stimulation is a feasible intervention for restoring arm and hand functions to individuals with high tetraplegia. Forces and movements were generated at the hand, wrist, elbow, and shoulder that allowed the performance of activities of daily living, with some limitations requiring the use of a mobile arm support to assist the stimulated shoulder forces.
Abstract Background context Instrumentation failure is a recognized complication after complex spinal reconstruction and deformity correction. Rod fracture (RF) is the most frequent mode of hardware ...failure in long-segment spinal fusion surgery. This complication can negatively impact the clinical outcome by producing spinal pain, functional compromise, instability, and loss of deformity correction. Purpose To describe the outrigger rod surgical technique. Study design Review of literature, case review, and surgical technique description. Patient sample Two clinical cases are presented. Outcome measures Rod fracture. Methods Outrigger rod placement in posterior spinal arthrodesis is performed by supplementing primary spinal rods with outrigger rods attached with cranial and caudal side-by-side connectors providing a more robust construct. Results This technique may be beneficial for preventing RF in patients undergoing surgery for three-column osteotomy for sagittal imbalance; pseudarthrosis surgery with previous hardware failure; transforaminal lumbar interbody cage placement at multiple levels in realignment procedures, long-segment spinal arthrodesis with impaired host fusion potential; long-segment instrumented fusions that span the cervicothoracic, thoracolumbar, or lumbosacral junction; and across spinal segments at high risk for RF (eg, after extensive resection of vertebral elements in the management of metastatic malignancy). Conclusions The risk of rod failure is substantial in the setting of long-segment spinal arthrodesis and corrective osteotomy. Efforts to increase the mechanical strength of posterior constructs may reduce the occurrence of this complication. The outrigger rod technique increases spinal construct stiffness and may improve the longevity of the construct. This technique should reduce the rate of device failure during maturation of posterior fusion mass and limit the need for supplemental anterior column support.
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