Neural transducers were small devices used to restore mobility to physically disabled individuals. They could pick up the neural signals from the brain and then stimulate the appropriate muscles. The implants were generally not one hundred percent effective, but did allow a patient to recover most mobility. Motor assist bands were first used to train the patient's nervous system before surgery.
Dr. Beverly Crusher and Dr. Toby Russell presented the neural transducers as an option to Lieutenant Worf following his spinal cord injury in 2368. He would have only been able to recover about sixty to seventy percent of his mobility with the implants. Worf was very unhappy with the prospect of such a life, and contemplated suicide before resorting to the risky genitronic replicator. (TNG: "Ethics")