Amee L Seitz

Northwestern University | NU · Department of Physical Therapy and Human Movement Sciences

Background Patients with persistent glenohumeral osteoarthritis symptoms despite nonoperative management may pursue anatomic total shoulder arthroplasty (TSA). TSA revision rates are higher in patients with preoperative eccentric (asymmetric posterior erosion) compared with concentric (symmetric) glenoid deformity. If posterior rotator cuff deficie...

OBJECTIVE: Guidelines include manual therapy and exercise for subacromial shoulder pain, but there is low certainty for these recommendations. Here, we evaluated if adding manual therapy to a resistance exercise program improved patient outcomes. DESIGN: Randomized parallel controlled clinical trial. METHODS: Individuals with subacromial pain syndr...

A clinical practice guideline on glenohumeral joint osteoarthritis was developed by an American Physical Therapy Association volunteer guideline development group that consisted of physical therapists, an occupational therapist, and a physician. The guideline was based on systematic reviews of current scientific and clinical information and accepte...

Background Despite shoulder and elbow injuries being common in athletics, return to sport and reinjury rates are less than ideal. These outcomes may be driven by the absence of evidence-informed testing to determine an athlete’s readiness for sport. Purpose The purpose of this study was to explore the reported frequency of physical performance tes...

Background: Shoulder ultrasound is a well-established point-of-care diagnostic modality in orthopaedic and sports medicine. Despite offering measurements of high-quality morphology, this methodology has faced several challenges, including variability in ultrasound systems, operator dependency, and lack of reliable and objective quantitative measure...

Study objective: Low back pain is a common reason for visiting the emergency department (ED), yet little is known about patient motivations for seeking emergency care. The purpose of this study was to explore patient perspectives on visiting the ED for low back pain to inform a more patient-centered approach to emergency care. Methods: We conduc...

Research Objectives Rotator cuff muscles are commonly regarded as the main stabilizers of the glenohumeral joint, but recent modeling work from our group suggests that muscles which primarily move the shoulder also contribute substantially to glenohumeral stiffness. The objective of this study was to evaluate this possibility in experiments designe...

Background: When nonoperative measures do not alleviate the symptoms of glenohumeral osteoarthritis (OA), patients with advanced OA primarily are treated with anatomic total shoulder arthroplasty (TSA). It is unknown why TSAs performed in patients with eccentric (asymmetric glenoid wear) compared with concentric (symmetric glenoid wear) deformitie...

Introduction Low back pain is a common problem and a substantial source of morbidity and disability worldwide. Patients frequently visit the emergency department (ED) for low back pain, but many experience persistent symptoms at 3 months despite frequent receipt of opioids. Although physical therapy interventions have been demonstrated to improve p...

Muscle activation helps stabilize the glenohumeral joint and prevent dislocations, which are more common at the shoulder than at any other human joint. Feedforward control of shoulder muscles is important for protecting the glenohumeral joint from harm caused by anticipated external perturbations. However, dislocations are frequently caused by unex...

Background: Clinicians of many specialties within sports medicine care for athletes with shoulder instability, but successful outcomes are inconsistent. Consistency across specialties in the diagnosis of shoulder instability is critical for care of the athlete, yet the extent of divergence in its diagnosis is unknown. Hypothesis: Physicians diff...

Purpose: Glenohumeral instability accounts for 23% of all shoulder injuries among collegiate athletes. The apprehension position-combined shoulder abduction and external rotation-commonly reproduces symptoms in athletes with instability. Rehabilitation aims to increase glenohumeral stability by strengthening functional positions. However, it is un...

Background: Fatty infiltration of the rotator cuff evaluated with CT has been associated with asymmetric glenoid wear and humeral head subluxation in patients with glenohumeral arthritis. The relationship between rotator cuff pathologic findings and abnormal glenoid wear plays an important role in determining the optimal surgical management of adv...

Rationale and Objectives. Recent evidence suggests an inhomogeneous distribution intramuscular rotator cuff fat infiltration in a small sample of individuals with rotator cuff tears, yet clinically just a few slices at the scapular Y-view are used to evaluate FI in patients with rotator cuff tears. The purpose of this study was to determine if asse...

Background Individuals with subacromial pain present with a variety of contributing impairments related to the movement problem. The scapular assistance test (SAT) and scapula reposition test (SRT) are proposed to identify shoulder pain related to abnormal scapular movement or position. It remains unknown if scapular movement related impairments ar...

Introduction There is no established consensus regarding the optimal rehabilitation protocol following rotator cuff repair, including duration of immobilization, timing to initiate range of motion and resistance exercises, and the importance of supervised, formal therapy. The purpose of this study was to determine agreement in opinion regarding rot...

Shoulder instability has varying mechanisms of injury, direction, and severity. Classification systems based on clustering signs and symptoms have been developed to define subgroups of shoulder instability. Despite this attempt at homogeneity, multidirectional instability (MDI) suffers from the same lack of diagnostic clarity as low back pain. In t...

Background: Intramuscular fat infiltration is a critical factor in surgical decision-making and is the most important factor used to prognosticate surgical repair outcomes in patients with rotator cuff tears. Quantitative 3D assessment of total rotator cuff fat infiltration in patients with rotator cuff tears has been realized. However, a reproduc...

Daily tasks rely on our ability to generate multi-dimensional shoulder torques. When function is limited, strength assessments are used to identify impairments and guide treatment. However, these assessments are often one-dimensional and limited in their sensitivity to diagnose shoulder pathology. To address these limitations, we have proposed nove...

Background: Subacromial pain syndrome (SPS) accounts for as much as 44% of shoulder pain encountered by physical therapists. Thoracic spine thrust manipulation (TSTM) is effective in the short term for improving pain and function in individuals with SPS, but its mechanisms remain elusive. Furthermore, it is unknown whether individuals with SPS res...

Background: The goal of therapeutic exercise is to facilitate a neuromuscular response by increasing or decreasing muscular activity in order to reduce pain and improve function. It is not clear what dosage of exercise will create a neuromuscular response. Purpose: The purpose of this study was to assess the effects following a three-week home p...

Objective To determine which normalization method may best account for confounding individual factors, such as age or BMI, when quantifying fat infiltration on MRI in patients with rotator cuff tears, the effects of normalization using three different muscles (teres major; triceps brachii; teres minor) were compared. Methods Thirty-seven consecuti...

Objective: The study aim was to evaluate subacromial and internal impingement risk between shoulders (dominant/non-dominant) during dynamic motion using subject-specific anatomy and precise in vivo kinematics. Design: In a prospective cross-sectional study, 9 subjects underwent bilateral MR (N=18 shoulders) and fluoroscopic imaging during extern...

Background: Psychosocial factors are key determinants of health and can influence patient-reported outcomes after rotator cuff tears. However, to our knowledge, a systematic review of published studies has not been conducted to determine the degree of consistency and strength of the relationship between psychosocial factors and patient-reported ou...

Study design: Cross-sectional cohort. Introduction: Tendon collagen organization can be estimated by peak spatial frequency radius (PSFR) on ultrasound images. Characterizing PSFR can define the contribution of collagen disruption to shoulder symptoms. Purpose of the study: The purpose of this was to characterize the (1) supraspinatus tendon P...

Purpose: Shoulder dislocations present a potentially debilitating injury for soldiers and other groups of physically active adults. The purpose of this study was to determine the 10-year incidence rate of shoulder dislocations in soldiers, the percentage with recurrent instability, and risk factors for these injuries. Methods: This retrospective...

This study examines the association between strength measurements and supraspinatus tear in patients with shoulder pain. This study characterized determinants of abduction strength among patients with tears. A total of 208 patients with shoulder pain were recruited. Strength was tested using a handheld dynamometer. Supraspinatus tears were diagnose...

The significance of scapular dyskinesis is being challenged due to a lack of the association with pain and ability to predict injury in athletic populations. However, it is unknown whether asymptomatic overhead athletes with dyskinesis cope by normalizing scapular position with higher demand activities. The purpose of this study was to compare chan...

To test the reliability and validity of shoulder joint angle measurements from the Microsoft Kinect™ for virtual rehabilitation. Test-retest reliability and concurrent validity, feasibility study. Motion analysis laboratory. A convenience sample of 10 healthy adults. Shoulder joint angle was assessed in four static poses, two trials for each pose,...

Synopsis: The available body of knowledge on shoulder ultrasound imaging has grown considerably within the past decade, and physical therapists are among the many health care professions currently exploring the potential clinical integration of this imaging technology and the knowledge derived from it. Therefore, the primary purpose of this commen...

Alterations in scapular muscle activity have been theorized to contribute to abnormal scapular motion and shoulder pain, but pose challenges to quantify in the clinic. Rehabilitative Ultrasound Imaging (RUSI) has proved useful identifying dysfunction of lumbar regional stabilizing muscle activity, specifically contractile behavior. Although, recent...

In rehabilitation, exercise instructions are multi-modal and can include a focus of increasing mean activity of a target muscle and inhibiting aberrant synergistic muscle activity, particularly during shoulder exercises, such as the prone horizontal abduction (PHA). The purpose of this study was to determine the immediate effects and short-term ret...

Despite its significant benefits, clinical adoption of virtual rehabilitation is slow. One reason is that current systems are typically constrained to providing therapy for one specific motor deficit with a limited number of pre-defined therapeutic game exercises. Any adjustments to these exercises require high-level programming knowledge beyond th...

Purpose: To characterize the supraspinatus tendon thickness, subacromial space, and the relationship between tendon thickness and subacromial space to further elucidate the mechanisms of subacromial impingement syndrome. Methods: In a single-blind cross-sectional study, subjects were recruited with subacromial impingement syndrome (n = 20) and a...

Objective: A high prevalence of neovascularity in lower extremity tendinopathies has been reported. Neovascularity in those with rotator cuff tendinopathy exclusively has not been examined. The objective was to determine the prevalence of neovascularization in patients with rotator cuff tendinopathy compared with asymptomatic controls. Design: S...

The Orthopaedic Section of the American Physical Therapy Association (APTA) has an ongoing effort to create evidence-based practice guidelines for orthopaedic physical therapy management of patients with musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability, and Health (ICF)...

Alterations in scapular muscle activity, including excess activation of the upper trapezius (UT) and onset latencies of the lower trapezius (LT) and serratus anterior (SA) muscles, are associated with abnormal scapular motion and shoulder impingement. Limited information exists on the reliability of neuromuscular activity to demonstrate the efficac...

Differences in 3-dimensional (3D) scapular motion have been reported between healthy baseball position players and healthy nonoverhead athletic controls, as well as players diagnosed with shoulder impingement syndrome. These alterations are theorized to be the result of adaptations due to the demands of repetitive throwing. However, comparisons bet...

Context: The literature does not present a consistent pattern of altered scapular kinematics in patients with shoulder-impingement syndrome (SIS). Objectives: To perform meta-analyses of published comparative studies to determine the consistent differences in scapular kinematics between subjects with SIS and controls. In addition, the purpose wa...

Controlled laboratory study. To determine the effect of the modified scapular assistance test (SAT) on 3-dimensional shoulder kinematics, strength, and linear measures of subacromial space in patients with subacromial impingement syndrome (SAIS). Abnormal scapular kinematics have been identified in patients with SAIS. Increased scapular upward rota...

CONTEXT: Differences in three-dimensional (3D) scapular motion have been reported between healthy baseball position players and healthy non-overhead athletic controls, as well as players diagnosed with shoulder impingement syndrome. These alterations are theorized to be the result of adaptations due to the demands of repetitive throwing. However, c...

Recently sonography (US) has been used to measure the subacromial space outlet with a linear measurement of the acromiohumeral distance (AHD). The purpose of this article is to systematically review the literature on the influence of rotator cuff disease (RCD) on AHD using US. Computer-aided searches of databases were performed to identify comparat...

Scapular dyskinesis is an abnormal scapular motion or position during active arm elevation. Dyskinesis is theorized to contribute to impingement syndrome by decreasing the subacromial space. A corrective maneuver of the scapular assistance test (SAT) proposes to increase scapular upward rotation and posterior tilt to increase the subacromial space....

The etiology of rotator cuff tendinopathy is multi-factorial, and has been attributed to both extrinsic and intrinsic mechanisms. Extrinsic factors that encroach upon the subacromial space and contribute to bursal side compression of the rotator cuff tendons include anatomical variants of the acromion, alterations in scapular or humeral kinematics,...

INTRODUCTION The Vicon Plug-In Gait (PiG) model is a commercially available biomechanical model for calculating joint kinematics using the Newington-Helen Hayes marker set. The PiG has been criticized by some for its simplistic marker set based on anatomic landmarks, which may increase the negative effect of soft tissue artifact and marker placemen...

Controlled laboratory study. To examine the effects of altering posture on the subacromial space (SAS) in subjects with rotator cuff disease and subjects without shoulder pain. Poor upper quadrant posture has been linked to altered scapular mechanics, which has been theorized to excessively reduce SAS. However, no study has examined the direct effe...

Reference/Citation Kuhn JE. Exercise in the treatment of rotator cuff impingement: a systematic review and a synthesized evidence-based rehabilitation protocol. J Shoulder Elbow Surg. 2009;18(1):138–160. Clinical Question What is the role of exercise in the treatment of rotator cuff impingement syndrome (RCIS), and what evidence-based exercises ca...