Shoulder arthroplasty for glenohumeral osteoarthritis: results from a comprehensive survey in Belgium and the Netherlands.

The purpose of this survey in Belgium and the Netherlands was to assess treatment variation in glenohumeral osteoarthritis between experienced and less experienced orthopedic surgeons, and to investigate perioperative treatment after shoulder arthroplasty in a large group of orthopedic surgeons. Orthopedic surgeons specialized in shoulder surgery were invited to complete a survey between November 2013 and February 2015. Seventy-one percent of the approached surgeons com-pleted the survey. Less experienced surgeons (< 6 years) and surgeons from the Netherlands find patient characteristics (e.g. smoking p=0.01) more relevant than more experienced surgeons (≥ 6 years) and surgeons from Belgium. Less experienced surgeons will less likely (p=0.001) perform resurfacing arthroplasty compare to experienced surgeons. The less and the experienced surgeons use similar indications for a reverse shoulder arthroplasty regarding age limit and cuff arthropathy without osteoarthritis. Less experienced surgeon will more likely (p=0.003) prescribe a low molecular weight heparin during the hospital stay after a shoulder arthroplasty. In this survey, we found a decrease in the use of resurfacing arthroplasty and a strong increase in the use of reverse shoulder arthroplasty. Besides, there is little consensus concerning pre-operative planning, patient characteristics, surgical technique, and patient reported outcome measures. Level of evidence: IV.

Accuracy of patient-specific guided implantation of the glenoid component in reversed shoulder arthroplasty.

BACKGROUND: The aim of this study was to assess the accuracy of patient-specific guided glenoid component implantation in reverse shoulder arthroplasty. MATERIALS AND METHODS: 32 reverse shoulder arthroplasties were done using preoperative 3D planning and 4 patient-specific guides to prepare the glenoid and position the glenoid component. Baseplate version, inclination and entry point as well as angulation of the screws were compared to the preoperative plan measured on CT by independent observers. RESULTS: The mean deviation in baseplate version from the preoperative plan was 4.4°+3.1° (range, 0.3°-13.7°), in baseplate inclination 5.0°+4.2° (range, 0.1° to 14.5°) and in baseplate entry point 2.4mm+1.4mm (range, 0.4° to 6.3°). The average screw superior-inferior angulation deviation for the superior screw was 2.8°+2.6° (range, 0.0°-10.1°) and 2.8+2.6° in the antero-posterior plane (range, 0.1°-11.6°). For the inferior screw the superior-inferior angle deviation was 5.3°+3.8° (range, 0.1°-15.2°); the antero-posterior angle deviation was 4.1°+3.1° (range, 0.0°-9.8°). CONCLUSIONS: Patient-specific instrumentation (PSI) for the glenoid component in reverse shoulder arthroplasty allows the shoulder surgeon to accurately execute the preoperative 3D plan. LEVEL OF EVIDENCE: Level 3.

Reverse shoulder arthroplasty in young patient with achondroplasia - Ten year follow up: Case report.

Skeletal dysplasia in achondroplasia can affect all body joints - including the glenohumeral joint - and is prone to develop to degenerative osteoarthritis (OA). This may cause pain and mobility problems at young age. Surgical treatment is challenging due to the dysplastic anatomy of the shoulder joint - with a dysplastic deformed short humerus, a small, hypoplastic medialized glenoid and lateralized acromion - and the long life expectancy of these patients. The indications for reverse shoulder arthroplasty (RSA) evolved during years with rotator cuff tears and rotator cuff arthropathy in combination with or without glenohumeral OA as the main indicator, with good short to mid-term results. Long term results of RSA are rarely found in literature, especially in young patients. The use of a RSA in glenohumeral OA with an intact rotator cuff has rarely been reported. In this case report we present the ten-year clinical and radiographic results of a RSA for the treatment of degenerative OA with glenohumeral dysplasia in a young patient with achondroplasia.

Radiological and clinical outcome of arthroscopic labral repair with all-suture anchors.

PURPOSE: The aim of this study was to assess radiological and clinical outcome after arthroscopic all--suture anchor labral repair. METHOD: 20 patients treated for anterior and superior labral instability (mean age 29, range 14-51 years) were assessed at a minimum follow-up time of 1 year (mean 19 months ; range, 12-28 months). Postoperative MRI scans were assessed by 3 independent radiologists. The radiological appearance of bone at the anchor-site was judged by the presence of cyst formation, tunnel widening (> 2 mm) or bone edema. Clinical outcome analysis included standard follow-up and the Disabilities of the Arm, Shoulder and Hand score (DASH), Constant Shoulder score and the Western Ontario Shoulder Instability Index (WOSI). RESULT: All patients were available for follow-up. In total, 58 all-suture anchors were implanted. None of the patients displayed large cyst formation. Small cysts were found in two patients (2 anchors). Tunnel widening was apparent in 3 patients (3 anchors) with an average widening of 3.3 mm (range 3-4 mm). Bone edema at the anchor-site was seen in 6 patients (8 anchors). The remaining 9 patients (45 anchors) did not display reactive bone changes. Clinical outcomes showed a WOSI of 70.6, a DASH of 18.9 and a Constant score of 89.3, and no recurrence of instability. CONCLUSIONS: Satisfying radiological and clinical outcome was observed after arthroscopic instability surgery using all-suture anchors. Imaging revealed good labral healing without important bony reactions or the formation of large cysts at early follow-up. Level of evidence : IV Case series.

Arthroscopic subacromial decompression for advanced (stage II) impingement syndrome: a study of 52 patients with five years follow-up.

The authors report a prospective five-year follow-up study of 52 patients who had arthroscopic subacromial decompression for advanced (stage II: type 1 and 2) rotator cuff disease. All patients were assessed preoperatively, at six months and at five years postoperatively using the Constant-Murley score and the revised American Shoulder and Elbow Surgeons (ASES) score. From six months until five years postoperatively, 45 (out of 52) patients showed a further progressing improvement and relief of symptoms. This is established by a significant (p < 0.001) increase of the mean Constant-Murley score from 76.4 at six months postoperatively to 84.9 at five years postoperatively.

The role of interstitial fluid flow in the remodeling response to fatigue loading.

Load-induced fluid flow enhances molecular transport through bone tissue and relates to areas of bone resorption and apposition. Remodeling activity is highly coordinated and necessitates a means for cellular communication via intracellular and extracellular means. Osteocytes, osteoblasts, and osteoclasts, which reside in disparate locations within the tissue, communicate intracellularly via the cellular syncytium and extracellularly via the pericellular fluid space of the lacunocanalicular system. Both of these communications systems are physically disrupted by microdamage incurred during fatigue loading of bone. The purpose of this study was to develop an analytical model to understand the role of interstitial fluid flow in the remodeling response to fatigue loading. Adequate transport was assumed a prerequisite for maintenance of cell viability in bone. Diffusive and convective transport were simulated through the lacunocanalicular network in a healthy undamaged state as well as in a damaged state after fatigue loading. The model predicts that fatigue damage impedes transport from the blood supply, depleting the concentration of molecular entities in and downstream from areas of damage. Furthermore, the presence of microcracks alters the distribution of molecular entities between individual lacunae. These effects were confirmed by the results of an in vivo pilot study in which fluorescent, flow-visualizing agents pooled within microcracks and were absent from areas surrounding microcracks, corresponding to areas deprived of fluid flow. Loss of osteocyte viability is coupled to targeting and initiation of new remodeling activity. Taken as a whole, these data suggest a link between interstitial fluid flow, mass transport, maintenance of osteocyte viability, and modulation of remodeling activity.

A retroperitoneal tumor as a late complication of the use of bone wax.

Ordinary bone wax was used to stop bleeding from the iliac crest after procurement of autogenous bone graft harvesting. This gave rise to a large, symptomatic retroperitoneal tumor, which had to be removed operatively 19 years later. Microscopically, a bone wax granuloma was diagnosed. As far as the authors know this is the first case reported with such late and severe clinical complications after the use of bone wax.

Decline in osteocyte lacunar density in human cortical bone is associated with accumulation of microcracks with age.

Despite osteocytes' ideal position to sense the local environment and thereby influence bone remodeling, the function of osteocytes in bone remains controversial. In this study, histomorphometric examination of male and female femoral middiaphyseal cortical bone was conducted to determine if bone's remodeling response, indicated by tissue porosity and accumulation of damage, is associated with osteocyte lacunar density (number of osteocyte lacunae per bone area). The results support the sensory role of the osteocyte network as the decline in osteocyte lacunar density in human cortical bone is associated with the accumulation of microcracks and increase in porosity with age. Porosity and microcrack density increased exponentially with a decline in osteocyte lacunar density indicating that a certain minimum number of osteocytes is essential for an "operational" network. No gender-related differences were found in the relationship of osteocyte lacunar density to age, porosity, or microcrack density. The coefficient of variation of osteocyte lacunar density increased linearly with age, indicating that aging bone tissue is characterized by increased heterogeneity in the spatial organization of osteocytes. Osteocyte lacunar density, porosity, and microcrack density exhibited the same exponential probability density distribution in the donor population, indicating their regulation by similar biological phenomena.

Loss of osteocyte integrity in association with microdamage and bone remodeling after fatigue in vivo.

As a result of fatigue, bone sustains microdamage, which is then repaired by bone-remodeling processes. How osteoclastic activity is targeted at the removal of microdamaged regions of bone matrix is unknown. In the current studies, we tested the hypothesis that changes in osteocyte integrity, through the initiation of regulated cell death (apoptosis), are associated with fatigue-related microdamage and bone resorption. Ulnae of adult rats were fatigue-loaded to produce a known degree of matrix damage. Osteocyte integrity was then assessed histomorphometrically from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labeling (TUNEL)-stained sections to detect cells undergoing DNA fragmentation associated with apoptosis; toluidine blue-stained sections were used for secondary morphological confirmation. Ten days after loading, large numbers of TUNEL-positive osteocytes were found in bone surrounding microcracks and in bone surrounding intracortical resorption spaces (approximately 300% increases over controls, p < 0.005). TUNEL labeling in loaded ulnae at sites distant from microcracks or resorption foci did not differ from that in control bone. Osteocytes in toluidine blue-stained sections showed equivalent trends to TUNEL-stained sections, with significant increases in pyknotic nuclei and empty lacunae associated with microcracks and intracortical resorption spaces. TUNEL-positive osteocytes were observed around bone microdamage by 1 day after loading (p < 0.01 relative to baseline), and their number remained elevated throughout the entire experimental period. Increases in empty lacunae and decreases in normal osteocyte numbers were observed over time as well. These studies show that (1) osteocyte apoptosis is induced by bone fatigue, (2) this apoptosis is localized to regions of bone that contain microcracks, and (3) osteoclastic resorption after fatigue also coincides with regions of osteocyte apoptosis. The strong associations between microdamage, osteocyte apoptosis, and subsequent bone remodeling support the hypothesis that osteocyte apoptosis provides a key part of the activation or signaling mechanisms by which osteoclasts target bone for removal after fatigue-induced matrix injury.

Treatment of advanced impingement syndrome by arthroscopic subacromial decompression.

The authors report a prospective study on 40 patients to investigate shoulder function after arthroscopic subacromial decompression for advanced impingement syndrome (stage II) using a posterolateral and a posteromedial portal. There were no intraoperative or postoperative complications related to the use of these portals. All patients were assessed preoperatively and at 6 months postoperatively using the Constant-Murley Score and the revised ASES Score. Before operation the mean Constant-Murley Score was 49.3. This improved to 78.2 at 6 months postoperatively (p < 0.0001). The ASES score improved from 35.6 preoperatively to 80.6 at 6 months postoperatively (p < 0.0001). Patient satisfaction, reflected by the affirmation that they would have the same operation again, was 85%. Comparison between the scoring systems using the Spearman rank correlation coefficient revealed a good correlation between the Constant-Murley score and the modified ASES score. The Spearman rank correlation coefficient for the pre- and postoperative scores was 0.995. (p < 0.0001).