Subject(s)
Blinking , Humans , Blinking/physiology , Male , Female , Middle Aged , Adult , Electromyography/methodsABSTRACT
OBJECTIVE: The blink reflex (BR) to supraorbital nerve (SON) stimulation is reduced by either a low-intensity prepulse stimulus to digital nerves (prepulse inhibition, PPI) or a conditioning SON stimulus (SON-1) of the same intensity as the test (SON-2) stimulus (paired-pulse paradigm). We studied how PPI affects BR excitability recovery (BRER) to paired SON stimulation. METHODS: Electrical prepulses were applied to the index finger 100 ms before SON-1, which was followed by SON-2 at interstimulus intervals (ISI) of 100, 300, or 500 ms. RESULTS: BRs to SON-1 showed PPI proportional to prepulse intensity, but this did not affect BRER at any ISI. PPI was observed on the BR to SON-2 only when additional prepulses were applied 100 ms before SON-2, regardless of the size of BRs to SON-1. CONCLUSIONS: In BR paired-pulse paradigms, the size of the response to SON-2 is not determined by the size of the response to SON-1. PPI does not leave any trace of inhibitory activity after it is enacted. SIGNIFICANCE: Our data demonstrate that BR response size to SON-2 depends on SON-1 stimulus intensity and not SON-1 response size, an observation that calls for further physiological studies and cautions against unanimous clinical applicability of BRER curves.
Subject(s)
Blinking , Prepulse Inhibition , Humans , Prepulse Inhibition/physiology , Fingers , Brain Stem , Reflex, Startle , Acoustic StimulationABSTRACT
The treatment and evaluation of a stiff and painful shoulder, characteristic of adhesive capsulitis and "frozen" shoulders, is a dilemma for orthopedic rehabilitation specialists. A stiff and painful shoulder is all-inclusive of Adhesive capsulitis and Frozen Shoulder diagnoses. Adhesive capsulitis and frozen shoulder will be referred to as a stiff and painful shoulder, throughout this paper. Shoulder motion occurs in multiple planes of movement. Loss of shoulder mobility can result in significant functional impairment. The traditional treatment approach to restore shoulder mobility emphasizes mobilization of the shoulder overhead. Forced elevation in a stiff and painful shoulder can be painful and potentially destructive to the glenohumeral joint. This manuscript will introduce a new biomechanical approach to evaluate and treat patients with stiff and painful shoulders.
Subject(s)
Bursitis/rehabilitation , Muscle Stretching Exercises/methods , Range of Motion, Articular/physiology , Recovery of Function/physiology , Shoulder Joint/physiopathology , Biomechanical Phenomena , Bursitis/diagnosis , Humans , Joint Capsule/physiopathology , Muscle, Skeletal/physiopathology , RotationABSTRACT
UNLABELLED: Dysfunction of the subscapularis muscle is introduced in this case report as a potential factor for consideration in the etiology and/or consequential sequelae of subacromial impingement syndrome. Although dysfunction of the supraspinatus and infraspinatus are implicated as being most commonly involved with subacromial impingement pathology, the subscapularis is often overlooked and therefore undertreated. Identifying the subscapularis' potential involvement in patients with subacromial impingement pathology may offer insight into shoulder impingement dysfunction and injury treatment options available to specifically address subscapularis dysfunction. In this manuscript, a case report is presented to highlight the signs and symptoms of subscapularis pathology concordant with subacromial impingement syndrome and provide a clinical rationale for treatment. The purpose of this case report is not to suggest a new approach to shoulder rehabilitation, but rather to prompt the consideration of subscapularis dysfunction when evaluating and treating patients with subacromial impingement pathology. LEVEL OF EVIDENCE: 5.
