Sensation Recovery

In the upper extremity:

Smania N, Montagnana B, Faccioli S, Fiaschi A, Aglioti SM. Rehabilitation of somatic sensation and related deficit of motor control in patients with pure sensory stroke. Arch Phys Med Rehabil. 2003 Nov;84(11):1692-702. PubMed PMID: 14639572.

Training Procedure

The treatment protocol consisted of exercises aimed at recovering somatic sensation and motor control of the affected hand. At the beginning of the training session, each patient was asked to perform a series of 25 exercises belonging to 1 of 9 main types of activity. A detailed description of the 9 groups of training activities is provided below. Next, the operator adjusted the protocol to the patient’s specific impairment by choosing exercises that were more challenging for the patient. After this preliminary selection phase, treatment was performed with only the selected exercises. If the patient was unable to perform a given exercise, the operator provided the patient with facilitations. At the end of each trial, the patient was given feedback about her/his performance (eg, number of hits or errors, details about execution, comments). Each patient underwent a total of 30 training sessions. Each patient was required to perform 1 daily hour of exercises at home that were similar to those of the training session. The patient was asked to record in a home diary each day the number and the type of exercises executed, as well as the difficulties encountered.

Tactile discrimination. We used 3 tactile discrimination tasks: sandpaper surfaces of different grains, surfaces made of different materials (eg, rubber, cloth, paper), and grating orientation. All exercises were performed without visual control. In the case of the sandpaper exercises, the operator passively guided tactile exploration to avoid possible skin lesions. 

Object recognition. This group included 3 tasks of tactile object recognition. In it, the blindfolded patient was requested to perform these tasks: manipulate a target object and discriminate it visually among 3 objects; manipulate a group of small objects (eg, rice, bolts, stones) and then discriminate visually among the 3 groups of objects; and manipulate 2 objects simultaneously with the affected and unaffected hand and then report whether the 2 objects were the same or different. 

Joint position sense. For these training activities, we used the same box as in the testing procedure for the joint position sense testing. This group included 3 tasks of proprioceptive discrimination. The operator moved the patient’s wrist or metacarpophalangeal joints at different angular positions by using the same methods previously described for the joint position test. The patient was required to choose which of 3 suggested positions of the protractor scale above the box corresponded to the real hand position. Using the affected hand, the patient was requested to actively reproduce the position indicated by the operator on the angular scale. The patient was asked to reproduce a gesture shown by the operator with the affected hand (ie, gesture of OK) while keeping her/his arm inside the box. 

Weight discrimination. The blindfolded patient was required to weigh an object with the affected hand. Then, he/she was required to weigh 3 objects with the unaffected hand and choose which of them corresponded in weight to the previous object. 

Motor sequences. This group included 2 tasks of finger motor sequencing. The blindfolded patient was asked to drum his/her fingers on the table according to a previously shown sequence. The blindfolded patient was required to play a sequence of notes on a piano keyboard. 

Reaching and grasping. The blindfolded patient was required to reach and grasp a common object placed on a wood board after having seen its position. The dimensions of the object varied to elicit different kinds of grasping (eg, pinch, whole-hand grasping). 

Item grouping. The blindfolded patient was required to separate several small objects (eg, buttons, paper clips) into homogeneous groups. 

Grasping strength grading. This group included 4 tasks. First, a cylindrical wood stick was used (70_4cm; 500g). The stick had several marks spaced at 5-cm distances. While holding the stick, the blindfolded patient was required to let the stick slide down, skipping 1 or more marks. Second, the blindfolded patient was required to move a plastic bottle filled from 30% to 60% with water from 1 side of the table to another. During the exercise, patients were asked not to produce any noise that could derive from compression of the plastic. Third, the patient was required to pick up and move objects of different dimensions and frailty (eg, crackers, paper cubes) by using ice pliers, without either compressing or breaking them. Last, the patient was required to squeeze a tube containing gel with the affected hand to obtain strips of variable length. 

Daily life activities. This group included 7 tasks: (1) grasping several toothpicks and putting them into a box; (2) stacking up several checker pieces; (3) folding up a sheet of paper and fitting it into an envelope; (4) making a braid with 3 cords made of soft material; (5) hooking up a spring catch to a metal ring while blindfolded; (6) fitting the affected hand into a glove; and (7) picking up several playing cards that had been laid on the table and turning them over while blindfolded.

In the upper limb:

Carey L, Macdonell R, Matyas TA. SENSe: Study of the Effectiveness of Neurorehabilitation on Sensation: a randomized controlled trial. Neurorehabil Neural Repair. 2011 May;25(4):304-13. Epub 2011 Feb 24. PubMed PMID: 21350049.

Experimental intervention.

The experimental intervention (EI) applied the principles of generalized sensory discrimination training14 to 3 sensory tasks: texture discrimination, limb position sense, and tactile object recognition. Training employed a variety of stimuli within each sensory dimension trained, graded progression of discriminations from easy to difficult, attentive exploration with vision occluded, anticipation trials, cross-modal calibration via vision, feedback on sensation and method of exploration, intermittent feedback and self-checking of accuracy, feedback on ability to identify distinctive features in novel stimuli, tuition of training principles, and summary feedback and intensive training.14 During each EI session, subjects were trained on each sensory task, in random sequence, for 15 to 20 minutes at a time. Texture discrimination training used graded stimuli with varying surface characteristics.14 Limb position sense was trained across a wide range of limb positions of the upper limb. Tactile object recognition training focused on discrimination of shape, size, weight, texture, hardness, and temperature using a range of multidimensional, graded objects.

In the lower extremity:

Lynch EA, Hillier SL, Stiller K, Campanella RR, Fisher PH. Sensory retraining of the lower limb after acute stroke: a randomized controlled pilot trial. Arch Phys Med Rehabil. 2007 Sep;88(9):1101-7. PubMed PMID: 17826453.

Sensory Retraining Intervention Ten 30-minute sensory retraining sessions were provided by the primary investigator over a 2-week period. The total treatment time was divided evenly between: education regarding sensation and sensory retraining; practice in detection and localization of touch at 7 points on the soles of the feet; hardness, texture and temperature discrimination by placing the feet on a variety of floor surfaces while sitting and standing with vision obscured; and proprioception training of the big toe and/or ankle (analogous to proprioceptive training at the wrist used in upper-limb sensory retraining8). The principles of sensory retraining were similar to those used in previous research8,9,12 and included education regarding the nature and extent of sensory loss; specific, graded stimulation tasks with an emphasis on tasks the subject was able to do (in this case, light touch detection and localization training was tailored for the individual to focus on areas of sensory deficit); attentive exploration of the stimuli by the subject; prevention of visual dominance; comparison with the nonaffected side; quantitative feedback.