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Due to the compromised bone situation revision implants need extended fixation options in order to achieve good long-term survival. Over decades this has been achieved with stems, either cemented or uncemented. In the last decade additional fixation options in terms of cementless metaphyseal sleeves or metaphyseal cones have been introduced and widely accepted. Revision of such implants is challenging, in particular if those porous coated parts are well integrated. Therefore, partial revision leaving the well-fixed parts in place can be an option if the indication is allowing it. This can help to preserve bone. In this study we show 2 cases with metaphyseal sleeves, in which we demonstrate when and how revision can be performed leaving sleeves in place.

Metaphyseal sleeves have shown an improved fixation in Revision Total Knee Arthroplasty (R-TKA) leading to a reduced aspetic loosening rate compared to other stem based fixation options. In the majority of these studies sleeve have been used with stems. Due to that is was not clear how much of this improved fixation could be rated to the sleeve and how much to the additional sleeves. In this review article we analysed the results of sleeve-only obtained in in-vitro or in-vivo studies.

Alterations of the shoulder girdle motion have been suggested to be associated with shoulder disorders. The objective of this study was to perform a three‐dimensional (3D) motion analysis of the supraspinatus muscle and shoulder girdle in patients with different stages of impingement syndrome. 20 patients with unilateral impingement and 14 normal controls were investigated at 30°, 90°, and 120° of abduction with and without abducting muscle activity. The spatial relationship between the shoulder girdle elements and the supraspinatus was quantified from open MRI data. No significant alterations in glenoid rotation were observed between the patients and asymptomatic volunteers. However, while in the healthy volunteers the values showed a normal distribution (28.5 ± 3.6° at 90° abduction with muscle activity), the patients (30.5° ± 9.7°) contained a subset of five individuals with an obvious increase in glenoid rotation angle (>40°) compared with controls (>2.5 standard deviations higher than the mean) and with the healthy contralateral side. These five patients also displayed alterations in the scapulo‐humeral rhythm and supraspinatus motion, but not in clavicular position. The study shows that only a specific subset of patients with impingement syndrome demonstrates complex changes in shoulder girdle and supraspinatus motion patterns, suggesting that this subset may benefit from an alternative type of treatment. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.

ObjectiveTo employ a magnetic resonance (MR) imaging technique for quantitative assessment of thin cartilage layers, and to validate the cartilage volume and thickness measurements.

Abstract:  In this investigation, patients with atraumatic posterior instability of the shoulder were appraised in order to evaluate the effectiveness of glenoid osteotomy in the correction of excessive retroversion and flatness of the glenoid. In a series of 32 patients, 17 with posterior instability had no history of trauma. Posterior glenoid osteotomy was performed to correct excessive retroversion and to deepen the glenoid; 95% were re-examined after 5 years. In 81% the results were rated as good or excellent (Constant-Murley and Rowe scores), only 12,5% having had a recurrence. The glenoid could be deepened and on average the angle could be altered from −9.35° to −4,62°. In comparison, 50 volunteers had average angles of −4,4°, thus differing significantly from the preoperative group. Twenty-five per cent of the patiens showed postoperative degenerative changes in the glenohumeral joint. The study shows that excessive retroversion and flatness of the glenoid in persons with atraumatic posterior instability can be successfully treated by a posterior glenoid osteotomy. Nevertheless, the high rate of postoperative degenerative changes must be taken into account.

Abstract The objectives of this study were to determine systematic changes of the normal subacromial space width during abduction and rotation, and to analyze the spatial relationship of the supraspinatus muscle with the acromion and clavicle. 12 healthy volunteers were imaged by an open MR scanner in 5 different positions of abduction and in 3 positions of rotation. After three dimensional (3D) reconstruction and 3D Euclidian distance transformation, the minimal spatial distances between the humerus and the acromion and the humerus and clavicle were computed. The minimal acromio-humeral distance decreased significantly from 30° of abduction (mean 7.0 mm ± 1.6 mm) to 120° (mean 3.9 mm; ± 1.8 mm; p < 0.0001). At 30°, the minimal distance penetrated the supraspinatus, whereas at 120° it was always located lateral to the supraspinatus tendon. At 90° with internal rotation (7.6 mm, ± 2.3 mm) the minimal acromio-humeral distance was larger than in neutral rotation (5.4 mm, ± 2.3 mm) or external rotation (4.4 mm, ± 2.2 mm; p < 0.05), but it penetrated the supraspinatus tendon at its most vulnerable part, reaching the acromion at its anterior inferior border. We conclude that the subacromial space width changes during abduction and rotation and that the supraspinatus is in closest contact to the anterior inferior border of the acromion in 90° of abduction with 45° internal rotation. These values obtained in volunteers can be used as a basis for further investigations in patients with the impingement syndrome.

Revision knee arthroplasty presents a number of challenges, not least of which is obtaining solid primary fixation of implants into host bone. Three anatomical zones exist within both femur and tibia which can be used to support revision implants. These consist of the joint surface or epiphysis, the metaphysis and the diaphysis. The methods by which fixation in each zone can be obtained are discussed. The authors suggest that solid fixation should be obtained in at least two of the three zones and emphasise the importance of pre-operative planning and implant selection.Cite this article: Bone Joint J2015;97-B:147–9.