Tanya Anne Mackenzie

An evidence-based review of current perceptions with regard to the subacromial space in shoulder impingement syndromes: Is it important and what influences it?

BACKGROUND Reduction of the subacromial space as a mechanism in the etiology of shoulder impingement syndromes is debated. Although a reduction in this space is associated with shoulder impingement syndromes, it is unclear if this observation is cause or consequence. METHOD The purposes of this descriptive review are to provide a broad perspective on the current perceptions with regard to the pathology and pathomechanics of subacromial and internal impingement syndromes, consider the role of the subacromial space in impingement syndromes, describe the intrinsic and extrinsic mechanisms considered to influence the subacromial space, and critique the level of evidence supporting these concepts. FINDING Based on the current evidence, the hypothesis that a reduction in subacromial space is an extrinsic cause of impingement syndromes is not conclusively established and the evidence permits no conclusion. INTERPRETATION If maintenance of the subacromial space is important in impingement syndromes regardless of whether it is a cause or consequence, research exploring the correlation between biomechanical factors and the subacromial space, using the later as the outcome measure, would be beneficial.

Assessment of the reliability of real time ultrasound scanning to measure the humeral head position in a number of glenohumeral joint positions

Abstract The aim of the current study is to assess the intra-rater and inter-rater reliability of real time ultrasound scanning in measuring static humeral head position. Real time ultrasound scanning, an experimental clinical

Quantitative Assessment of Glenohumeral Translation in Professional Golfers Using Ultrasound

Quantitative Assessment of Glenohumeral Translation in Professional Golfers Using Ultrasound Posterior hyper laxity of the glenohumeral joint could contribute to shoulder problems in golfers; hence, a measuring tool to quantify glenohumeral laxity clinically is important. Objective: Assess within-session intra-rater reliability of using Ultrasound to measure glenohumeral laxity, and quantify glenohumeral joint translation in symptom free elite golfers and non overhead athlete controls. Study design: Descriptive laboratory study. Ultrasound Scanning measured humeral head translation during the Drawer test in 30 asymptomatic professional golfers recruited on the PGA European Challenge Tour, and 10, asymptomatic, non overhead male athlete controls, all male and under the age of 40 years. Within-session intra-rater reliability coefficients (Intraclass correlation ICC3.1) were moderate to good, with scores of more than 0.75 (95% confidence interval 0.51-0.94) for the technique and instrumentation used. Posterior translation of the humeral head was 1.29 mm greater in golfers in the non dominant/lead shoulder compared with controls. This was statistically significant when p=0.01(Mann-Whitney U test). Conclusion: Real Time Ultrasound Scanning is a reliable method of assessing posterior glenohumeral laxity in golfers. Posterior translation of the humeral head was greater in golfers in the non dominant/lead shoulder compared with controls.

Low-grade infections in nonarthroplasty shoulder surgery

BACKGROUND Recent studies have identified the diagnostic challenge of low-grade infections after shoulder arthroplasty surgery. Infections after nonarthroplasty procedures have not been reported. This study assessed patient-related risk factors, outcomes, and clinical presentation of low-grade infection after open and arthroscopic nonarthroplasty shoulder surgery. METHODS The cases of 35 patients presenting with suspected low-grade infection were reviewed. Biopsy specimens taken at revision surgery were cultured in the sterile environment of a class II laminar flow cabinet and incubated for a minimum of 14 days at a specialist orthopedic microbiology laboratory. Patient-related factors (age, occupation, injection), index surgery, and infection characteristics (onset of symptoms, duration to diagnosis, treatment) were analyzed. RESULTS Positive cultures were identified in 21 cases (60.0%), of which 15 were male patients (71%). Of all patients with low-grade infection, 47.6% were male patients between 16 and 35 years of age. Propionibacterium acnes and coagulase-negative staphylococcus were the most common organisms isolated (81.1% [n = 17] and 23.8% [n = 5], respectively). Of 14 negative culture cases, 9 were treated with early empirical antibiotics (64.3%); 7 patients reported symptomatic improvement (77.8%). Of 5 patients treated with late empirical antibiotics, 4 stated improvement. Patients presented with symptoms akin to resistant postoperative frozen shoulder (persistent pain and stiffness, unresponsive to usual treatments). CONCLUSION Young male patients are at greatest risk for low-grade infections after arthroscopic and open nonarthroplasty shoulder surgery. P. acnes was the most prevalent organism. Patients presented with classic postoperative frozen shoulder symptoms, resistant to usual treatments. Interestingly, 78.6% of patients with negative cultures responded positively to empirical treatment.

Inter-rater Reliability of Real-Time Ultrasound to Measure Acromiohumeral Distance

Real‐time ultrasound (RTUS) has been suggested as a reliable measure of acromiohumeral distance. However, to date, no vigorous assessment and reporting of inter‐rater reliability of this method has been performed with the shoulder in a neutral position or with active and passive arm abduction.

Acromiohumeral Distance During Neuromuscular Electrical Stimulation of the Lower Trapezius and Serratus Anterior Muscles in Healthy Participants

CONTEXT Compromise to the acromiohumeral distance has been reported in participants with subacromial impingement syndrome compared with healthy participants. In clinical practice, patients with subacromial shoulder impingement are given strengthening programs targeting the lower trapezius (LT) and serratus anterior (SA) muscles to increase scapular posterior tilt and upward rotation. We are the first to use neuromuscular electrical stimulation to stimulate these muscle groups and evaluate how the muscle contraction affects the acromiohumeral distance. OBJECTIVE To investigate if electrical muscle stimulation of the LT and SA muscles, both separately and simultaneously, increases the acromiohumeral distance and to identify which muscle-group contraction or combination most influences the acromiohumeral distance. DESIGN Controlled laboratory study. SETTING Human performance laboratory. PATIENTS OR OTHER PARTICIPANTS Twenty participants (10 men and 10 women, age = 26.9 ± 8.0 years, body mass index = 23.8) were screened. INTERVENTION(S) Neuromuscular electrical stimulation of the LT and SA. MAIN OUTCOME MEASURE(S) Ultrasound measurement of the acromiohumeral distance. RESULTS Acromiohumeral distance increased during contraction via neuromuscular electrical stimulation of the LT muscle (t(19) = -3.89, P = .004), SA muscle (t(19) = -7.67, P = .001), and combined LT and SA muscles (t(19) = -5.09, P = .001). We observed no differences in the increased acromiohumeral distance among the 3 procedures (F(2,57) = 3.109, P = .08). CONCLUSIONS Our results supported the hypothesis that the muscle force couple around the scapula is important in rehabilitation and scapular control and influences acromiohumeral distance.

Sorting swimmers shoulders: An observational study on swimmers that presented to a shoulder surgeon.

Context: It is common for swimmers to suffer shoulder injuries resulting in a wealth of research focusing on the causes and types of injury. However, there is a lack of evidence regarding current management for shoulder injuries in swimmers. Aims: To investigate the diagnosis, subsequent management, and the return to swimming outcomes for swimmers presenting to an orthopedic practice. Settings and Design: Retrospective cohort study of competitive swimmers presenting to an orthopedic practice. Materials and Methods: The diagnosis, subsequent management, and the return to swimming outcomes were analyzed for 14 swimmers whose injuries were managed by a shoulder surgeon. Statistical Analysis Used: Descriptive analysis. Results: No significant association was identified between swimming stroke and type of injury. The majority of swimmers had good scapula rhythm, with no visible dyskinesis, including those with impingement. Swimmers with impingement did not require arthroscopy, and with nonoperative management had a mean time to return to swimming of 1.6 months. All labral tears required arthroscopic labral repair, with these swimmers having a mean time of 2.9 months postsurgery to return to swimming. Conclusion: The study demonstrated that an accurate diagnosis, and appropriate choice of nonoperative and surgical treatments lead to reassuring outcomes for swimmers suffering from shoulder injuries.

The effects of rigid scapular taping on acromio-humeral distance in healthy shoulders: an observational study

CONTEXT Compromise to the acromiohumeral distance (AHD) has been reported in subjects with subacromial impingement syndrome when compared with healthy subjects. In clinical practice, patients are taped with the intention of altering scapular position and influencing the AHD. However, research to determine the effects of taping on AHD is exiguous. OBJECTIVES To evaluate the effect of ridged taping techniques to increase posterior scapular tilt and upward scapular rotation on the AHD. DESIGN 1-group pretest/posttest repeated-measures design. SETTING Human performance laboratory. PARTICIPANTS 20 asymptomatic participants (10 male and 10 female) age 27 y (SD 8.0 y). INTERVENTION Ridged tapping of the scapula into posterior tilt and upward scapular rotation. MAIN OUTCOME MEASURE Ultrasound measurement of the AHD. RESULTS AHD increased significantly after rigid tape application to the scapula (P < .003) in healthy shoulders in 60° of passive arm abduction. CONCLUSION Taping techniques applied to the scapula had an immediate effect of increasing the AHD in healthy shoulders in 60° of passive arm abduction. Results suggest that taping for increasing posterior scapular tilt and increasing scapular upward rotation can influence the AHD and is a useful adjunct to rehabilitation in patients with subacromial impingement syndrome.

Shoulder injuries in adolescent rugby players

Background Rugby is a high-intensity contact sport, frequently causing shoulder injuries. Between the ages of 12 years to 18 years, academy and county level players are being selected for professional contracts, making this is a critical stage of their career. The present study aimed to describe the patterns of injury in adolescent rugby players with shoulder injuries. Methods Academy and county level rugby players in the target age group, over a 7-year period, were included in the present study. Data collected included the mechanism of injury, position and level of play, radiology and surgical findings, and recurrence rate at a minimum of 2 years post-surgery. Results One hundred and sixty-nine cases adhered to the inclusion criteria, with most cases involving two or more pathologies in the shoulder (54%). Forwards sustained more shoulder injuries than backs, incurring more labral injuries. By contrast, backs had a higher incidence of bony pathology. The mechanism of injury frequently correlated with player positions. There was a 21% injury recurrence rate, with forwards (7%) and higher level academy players (11%) most likely to suffer a recurrence. Conclusions Shoulder injury patterns in this important group of adolescent contact athletes are complex, with recurrence rates being higher than those in older rugby players.

Relationship between extrinsic factors and the acromio-humeral distance

BACKGROUND Maintenance of the subacromial space is important in impingement syndromes. Research exploring the correlation between biomechanical factors and the subacromial space would be beneficial. OBJECTIVES To establish if relationship exists between the independent variables of scapular rotation, shoulder internal rotation, shoulder external rotation, total arc of shoulder rotation, pectoralis minor length, thoracic curve, and shoulder activity level with the dependant variables: AHD in neutral, AHD in 60° arm abduction, and percentage reduction in AHD. DESIGN Controlled laboratory study. METHOD Data from 72 male control shoulders (24.28years STD 6.81 years) and 186 elite sportsmens shoulders (25.19 STD 5.17 years) were included in the analysis. The independent variables were quantified and real time ultrasound was used to measure the dependant variable acromio-humeral distance. RESULTS Shoulder internal rotation and pectoralis minor length, explained 8% and 6% respectively of variance in acromio-humeral distance in neutral. Pectoralis minor length accounted for 4% of variance in 60° arm abduction. Total arc of rotation, shoulder external rotation range, and shoulder activity levels explained 9%, 15%, and 16%-29% of variance respectively in percentage reduction in acromio-humeral distance during arm abduction to 60°. CONCLUSION Pectorals minor length, shoulder rotation ranges, total arc of shoulder rotation, and shoulder activity levels were found to have weak to moderate relationships with acromio-humeral distance. Existence and strength of relationship was population specific and dependent on arm position. Relationships only accounted for small variances in AHD indicating that in addition to these factors there are other factors involved in determining AHD.