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W J Mallon

Publications and source records attributed to W J Mallon.

26 records · Page 2Linked to original sources
PubMedDate not supplied

Reliability of radiographic assessment of acromial morphology.

The most widely used radiographic classification system for acromial morphology identifies three distinct acromial shapes: type I (flat), type II (curved), and type III (hooked). The purpose of this study was to measure the interobserver and intraobserver reliability of determinations of acromial morphology as defined by this system. Between 1990 and 1992, one hundred twenty-six supraspinatus outlet radiographs were obtained from 126 patients by technicians from Triangle Orthopaedic Associates in Durham, N.C. Six fellowship-trained shoulder surgeons independently reviewed each radiograph and classified it as type I, II, or III on the basis of established guidelines. Two surgeons classified each film a second time in random order. Analysis of variance was performed to obtain coefficients for interobserver and intraobserver reliability. Consensus ratings were then used to classify the 126 radiographs into consensus type I, consensus type II, or consensus type III groups. Percentages of type I, II, and III individual ratings within each consensus group were determined. The intraobserver reliability coefficient was 0.888, interpreted as good to excellent reliability. The interobserver reliability coefficient was 0.516, interpreted as poor to fair reliability. Of the 126 radiographs, 26 (20.6%) were rated as consensus type I, 76 (60.3%) were rated as consensus type II, and 24 (19.1%) were rated as consensus type III. The reliability of observer ratings was lowest when delineation between acromial types II and III was required. The low interobserver reliability makes comparisons of studies by different authors difficult to interpret and obscures the true incidence of acromial morphologic types. It also questions reported correlations between acromial type and shoulder pathologic conditions. It is concluded that a system that incorporates more objective classification criteria and acknowledges the continuous nature of acromial morphologic types may improve interobserver reliability and validate the system's use in making clinical and surgical judgments.

Acromion↗
PubMedDate not supplied

Multidirectional instability: current concepts.

Multidirectional instability (MDI) of the shoulder is a complex problem that is not yet well understood. Instability in several directions is termed MDI, but the precise definition, classification, cause, and optimal method of treatment remains elusive. The cause appears to be multifactorial, with biochemical and biomechanical abnormalities present in shoulders with MDI. The biomechanical factors responsible for preventing MDI include bony architecture, concavity-compression from the deepening of the glenoid by the labrum, stability from the ligaments, primarily the inferior glenohumeral ligament complex and the superior capsular structures, and muscular control by use of force couples, especially stabilization of the scapula. Current recommended treatment is initially nonoperative, with aggressive physical therapy aimed at strengthening the rotator cuff and the scapular stabilizers. Patients who fail to respond to a nonoperative regimen often improve with surgical stabilization, which is usually an inferior capsular shift or a variant of that procedure. After this surgery immobilization of the operated shoulder for 6 to 8 weeks is recommended by most authors.

Humans↗
PubMedDate not supplied

Use of vertebral levels to measure presumed internal rotation at the shoulder: a radiographic analysis.

Internal rotation of the shoulder is frequently measured by noting the maximal vertebral level reached by the patient's thumb, but it is not at all certain that this maneuver is strictly measuring internal rotation. We analyzed this maneuver with computed tomographic scans of the shoulder in differing positions. We also analyzed extension of the glenohumeral joint and scapulothoracic articulation with scapular lateral radiographs. Finally, we used posteroanterior radiographs to analyze elbow flexion at the limits of internal rotation behind the back. We found that maximal internal rotation behind the back occurs in approximately a 2 : 1 ratio between the glenohumeral joint and the scapulothoracic articulation. However, the scapulothoracic articulation was more significant in placing the arm behind the back, whereas the glenohumeral joint performed most of the internal rotation in front of the body. The scapulothoracic articulation assists in this motion by both extension and internal rotation of the scapula on the thorax. The limits of internal rotation behind the back are reached with a significant contribution from elbow flexion. We conclude that measuring shoulder internal rotation by the maximal vertebral level reached by the patient's thumb greatly oversimplifies the concept of internal rotation and that limitations in this motion may not be strictly due to a loss of internal rotation at the glenohumeral joint.

Adult↗
PubMedDate not supplied

Reliability and reproducibility of radiographic interpretation of proximal humeral fracture pathoanatomy.

Recent studies have demonstrated inconsistencies in the use of certain images for classifying proximal humerus fractures. Our purpose was to determine whether three-dimensional computed tomography or the level of expertise of the observers would improve the reliability and reproducibility of identifying specific anatomic fragments in proximal humerus fractures. Two groups of observers, nonexperts and experts in shoulder surgery, were asked to review the radiographs and three-dimensional computed tomography scans of 12 patients with proximal humerus fractures. Observers were asked to identify displaced fracture fragments, dislocation, and articular surface fractures. Both groups of observers displayed suboptimal reliability for the identification of displaced fracture fragments. The addition of three-dimensional computed tomography scans did not improve the reliability or reproducibility. Poor agreement for the purpose of classification seems to occur at the most fundamental level, the pathoanatomic description of the fracture. Inconsistencies may have been due to imprecise identification and measurement of individual fracture fragments, differing interpretations of the pathoanatomy, or both.

Humans↗
PubMedDate not supplied

E. Amory Codman, surgeon of the 1990s.

Ernest Amory Codman is known to orthopaedists primarily for his work in shoulder surgery. But his contributions reached many other fields of medicine, including pathology, radiology, anesthesiology, and most surgical subspecialties. Perhaps his most important work was that on the "end result idea," an early approach to outcome studies that anticipated much of the current health-care climate. This article examines his life and explains his contributions to medicine and surgery and their pertinence to current practice.

Boston↗
PubMedDate not supplied

Patient-controlled lidocaine analgesia for acromioplasty surgery.

Twenty-four consecutive patients undergoing shoulder acromioplasty were given postoperative analgesia with a new method in which a patient-controlled continuous infusion of lidocaine infiltrated the subacromial space. Seventeen of the acromioplasties were done with arthroscopy, whereas 7 were performed with an open procedure. A 2% solution of lidocaine without epinephrine was used for both a continuous dose of 2 cc/h and patient-controlled interval doses of 1 cc administered at 15-minute intervals. The catheter was left in place for 72 hours. We prospectively studied complications, the patient's subjective pain level, the amount of supplementary pain medication used, and serum levels of lidocaine. In addition, we evaluated a control group of 24 patients undergoing acromioplasty by the same surgeon without the use of this method of pain control. No wound complications occurred. No adverse reactions to lidocaine or overdose of lidocaine occurred. Blood levels of lidocaine averaged 0.3 microgram/mL in the 12 patients studied. Subjective pain levels and the amount of supplementary pain medication used were both lower in the group receiving patient-controlled lidocaine analgesia at statistically significant levels (P = .168 measuring subjective pain level, and P = .0212 measuring supplementary pain medication use). Patient-controlled lidocaine analgesia in the subacromial space appears to be a safe method for achieving high levels of pain control in patients undergoing an acromioplasty.

Acromioclavicular Joint↗