PURPOSE The triradiate cartilage transiently projects medially within the pelvic brim around the time of triradiate closure, mimicking the ischial spine sign. The purpose of this study was to characterize this newly identified radiographic sign using a longitudinal radiographic study. METHODS We identified 72 subjects from a longitudinal radiographic study of healthy adolescents, each with at...

The throwing shoulder in pitchers frequently exhibits a paradox of glenohumeral joint motion, in which excessive external rotation is present at the expense of decreased internal rotation. The object of this study was to determine the role of humeral head retroversion in relation to increased glenohumeral external rotation. Glenohumeral joint range of motion and laxity along with humeral head a...

We undertook a prospective MRI study to measure the retroversion of the humeral head in 33 consecutive infants with a mean age of 1 year 10 months (3 months to 7 years 4 months) who had an obstetric brachial plexus lesion (OBPL). According to a standardised MRI protocol both shoulders and humeral condyles were examined and the shape of the glenoid and humeral retroversion determined. The mean h...

BACKGROUND Femoroacetabular impingement (FAI) is a well-recognized condition that causes hip pain and can lead to early osteoarthritis if not managed properly. With the increasing awareness and efficacy of operative treatments for pincer-type FAI, there is a need for consensus on the standardized radiographic diagnosis. PURPOSE To perform a systematic review of the evidence regarding imaging ...

Recurrent dislocation after total hip replacement usually demands revision. Ahnfelt (1986) reported 626 disbocations of which 79 (1 1.2%) dislocated twice, 33 (5.1%) three times and 40 dislocated (6.6%) four times. We now report the results of treating 1 3 cases of recurrent dislocation by fixing an additional sector to the posterior rim ofthe acetabular component after Charnley total hip repla...

Most osteoarthritis of the hip is associated with chronic abnormal hip mechanics,1 related to potentially treatable anatomic abnormalities.2 The rationale of mechanically-based measures to prevent or treat osteoarthrosis assumes the following: (a) the correctable mechanical abnormality is a major etiologic factor in osteoarthrosis; (b) relief of the mechanical abnormality can prevent or improve...

A reduced retroversion angle of the humeral head may predispose to recurrent anterior shoulder dislocation and may also be a factor in persistent instability after soft-tissue repair. We performed rotational osteotomy of the proximal humerus in 20 patients with recurrent anterior shoulder dislocations (10 traumatic, 10 non-traumatic) and a decreased retroversion angle of the humeral head. The m...

Background: Managing posterior glenoid wear and retroversion remains a challenge in shoulder arthroplasty.Correcting glenoid version through asymmetric reaming (AR) with placement of a standard glenoid component and theuse of posteriorly augmented glenoid (PAG) components are two methods used to address this problem. Our objectiveis to report the radiographic outcomes of patie...