Histomorphometric Assessment of Cancellous and Cortical Bone Material Distribution in the Proximal Humerus of Normal and Osteoporotic Individuals Significantly Reduced Bone Stock in the Metaphyseal and Subcapital Regions of Osteoporotic Individuals

Osteoporosis is a systemic disorder predominantly affecting postmenopausal women but also men at an advanced age. Both genders may suffer from low-energy fractures of, for example, the proximal humerus when reduction of the bone stock or/and quality has occurred. The aim of the current study was to compare the amount of bone in typical fracture zones of the proximal humerus in osteoporotic and non-osteoporotic individuals. The amount of bone in the proximal humerus was determined histomorphometrically in frontal plane sections. The donor bones were allocated to normal and osteoporotic groups using the T-score from distal radius DXA measurements of the same extremities. The T-score evaluation was done according to WHO criteria. Regional thickness of the subchondral plate and the metaphyseal cortical bone were measured using interactive image analysis. At all measured locations the amount of cancellous bone was significantly lower in individuals from the osteoporotic group compared to the non-osteoporotic one. The osteoporotic group showed more significant differences between regions of the same bone than the non-osteoporotic group. In both groups the subchondral cancellous bone and the subchondral plate were least affected by bone loss. In contrast, the medial metaphyseal region in the osteoporotic group exhibited higher bone loss in comparison to the lateral side. This observation may explain prevailing fracture patterns, which frequently involve compression fractures and certainly has an influence on the stability of implants placed in this medial region. It should be considered when planning the anchoring of osteosynthesis materials in osteoporotic patients with fractures of the proximal humerus

Concomitant glenohumeral injuries in Neer type II distal clavicle fractures

Background: To identify the prevalence of concomitant glenohumeral injuries in surgically treated Neer type II distal clavicle fractures and relate its clinical importance. Methods: Between 11/2011 and 11/2015 41 patients, suffering from a displaced and unstable distal clavicle fracture were included. 20 patients (group 1) received surgical treatment by means of plate osteosynthesis in combination with an arthroscopically assisted coraco-clavicular ligament augmentation. In group 2 (n = 21 patients) the fracture was treated by hooked plating solely, and diagnostic arthroscopy was conducted during hardware retrieval after the fracture had healed. All arthroscopies were performed in a standardized fashion, images were blinded retrospectively, and evaluated by two independent investigators. Results: In total, concomitant glenohumeral pathologies were found in 26.8% of cases (41 patients, mean age 43.6 +/- 16. 6 years). In Group 1 (n = 20, arthroscopically assisted fracture treatment) the prevalence was 25%, in Group 2 (n = 21, diagnostic arthroscopy during implant removal) 28.5% (p = 0.75). Concomitant glenohumeral injuries included Labrum-and SLAP-tears, partial and full thickness rotator cuff tears as well as lesions to the biceps pulley system. Concomitant injuries were addressed in 2 patients of group 1 (10%, 2x labrum repair) and in 3 patients of group 2 (14.3%, of Group 2 (2x arthroscopic cuff repair of full thickness tear, 1x subpectoral biceps tenodesis in an type IV SLAP lesion, p = 0.68). Conclusion: The present study could clarify the acute and for the first time mid-term implication and clinical relevance of concomitant glenohumeral injuries. They have been observed in averaged 27% of Neer type II distal clavicle fractures at these two times. However, the findings of this study show that not all concomitant lesions remain symptomatic. While lesions are still present after fracture healing, it's treatment may be depicted upon symptoms at the time of implant removal. In turn, early diagnosis and treatment of concomitant injuries seems reasonable, as untreated injuries can remain symptomatic for more than 6 months after the fracture and recovery may be delayed

Operative treatment of 2-part surgical neck fractures of the proximal humerus (AO 11-A3) in the elderly: Cement augmented locking plate Philos (TM) vs. proximal humerus nail MultiLoc (R)

Background: Proximal humeral fractures are with an incidence of 4-5 % the third most common fractures in the elderly. In 20 % of humeral fractures there is an indication for surgical treatment according to the modified Neer-Criteria. A secondary varus dislocation of the head fragment and cutting-out are the most common complications of angle stable locking plates in AO11-A3 fractures of the elderly. One possibility to increase the stability of the screw-bone-interface is the cement augmentation of the screw tips. A second is the use of a multiplanar angle stablentramedullary nail that might provide better biomechanical properties after fixation of 2-part-fractures. A comparison of these two treatment options augmented locking plate versus multiplanar angle stable locking nail in 2-part surgical neck fractures of the proximal humerus has not been carried out up to now. Methods/Design: Forty patients (female/male, = 60 years or female postmenopausal) with a 2-part-fracture of the proximal humerus (AO type 11-A3) will be randomized to either to augmented plate fixation group (PhilosAugment) or to multiplanar intramedullary nail group (MultiLoc). Outcome parameters are Disabilities of the Shoulder, Arm and Hand-Score (DASH) Constant Score (CS), American Shoulder and Elbow Score (ASES), Oxford Shoulder Score (OSS), Range of motion (ROM) and Short Form 36 (SF-36) after 3 weeks, 6 weeks, 3 months, 6 months, 12 and 24 months. Discussion: Because of the lack of clinical studies that compare cement augmented locking plates with multiplanar humeral nail systems after 2-part surgical neck fractures of the proximal humerus, the decision of surgical method currently depends only on surgeons preference. Because only a randomized clinical trial (RCT) can sufficiently answer the question if one treatment option provides advantages compared to the other method we are planning to perform a RCT

The intravascular volume effect of Ringer's lactate is below 20%: a prospective study in humans

Introduction: Isotonic crystalloids play a central role in perioperative fluid management. Isooncotic preparations of colloids (for example, human albumin or hydroxyethyl starch) remain nearly completely intravascular when infused to compensate for acute blood losses. Recent data were interpreted to indicate a comparable intravascular volume effect for crystalloids, challenging the occasionally suggested advantage of using colloids to treat hypovolemia. General physiological knowledge and clinical experience, however, suggest otherwise. Methods: In a prospective study, double-tracer blood volume measurements were performed before and after intended normovolemic hemodilution in ten female adults, simultaneously substituting the three-fold amount of withdrawn blood with Ringer's lactate. Any originated deficits were substituted with half the volume of 20% human albumin, followed by a further assessment of blood volume. To assess significance between the measurements, repeated measures analysis of variance (ANOVA) according to Fisher were performed. If significant results were shown, paired t tests (according to Student) for the singular measurements were taken. P < 0.05 was considered to be significant. Results: A total of 1,097 +/- 285 ml of whole blood were withdrawn (641 +/- 155 ml/m2 body surface area) and simultaneously replaced by 3,430 +/- 806 ml of Ringer's lactate. All patients showed a significant decrease in blood volume after hemodilution (-459 +/- 185 ml; P < 0.05) that did not involve relevant hemodynamical changes, and a significant increase in interstitial water content (+ 2,157 +/- 606 ml; P < 0.05). The volume effect of Ringer's lactate was 17 +/- 10%. The infusion of 245 +/- 64 ml of 20% human albumin in this situation restored blood volume back to baseline values, the volume effect being 184 +/- 63%. Conclusions: Substitution of isolated intravascular deficits in cardiopulmonary healthy adults with the three-fold amount of Ringer's lactate impedes maintenance of intravascular normovolemia. The main side effect was an impressive interstitial fluid accumulation, which was partly restored by the intravenous infusion of 20% human albumin. We recommend to substitute the five-fold amount of crystalloids or to use an isooncotic preparation in the face of acute bleeding in patients where edema prevention might be advantageous

One-year follow-up-case report of secondary tension pneumothorax in a COVID-19 pneumonia patient

PURPOSE The Coronavirus Disease 2019 (COVID-19) may result not only in acute symptoms such as severe pneumonia, but also in persisting symptoms after months. Here we present a 1~year follow-up of a patient with a secondary tension pneumothorax due to COVID-19 pneumonia. CASE PRESENTATION In May 2020, a 47-year-old male was admitted to the emergency department with fever, dry cough, and sore throat as well as acute chest pain and shortness of breath. Sputum testing (polymerase chain reaction, PCR) and computed tomography (CT) confirmed infection with the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Eleven days after discharge, the patient returned to the emergency department with pronounced dyspnoea after coughing. CT showed a right-sided tension pneumothorax, which was relieved by a chest drain (Buelau) via mini open thoracotomy. For a period of 3~months following resolution of the pneumothorax the patient complained of fatigue with mild joint pain and dyspnoea. After 1~year, the patient did not suffer from any persisting symptoms. The pulmonary function and blood parameters were normal, with the exception of slightly increased levels of D-Dimer. The CT scan revealed only discrete ground glass opacities (GGO) and subpleural linear opacities. CONCLUSION Tension pneumothorax is a rare, severe complication of a SARS-CoV-2 infection but may resolve after treatment without negative long-term sequelae. LEVEL OF EVIDENCE V

Osseous microarchitecture in frequent fracture zones of the distal clavicle.

BACKGROUND Fracture classifications of the distal clavicle are based on ligamentous integrity. The influence of osseous microarchitecture on fracture occurrence, morphology, and the lesion's stability has not yet been investigated. We aimed to characterize osseous microarchitecture according to common fracture classification systems based on ligamentous integrity and investigated the possible effects of age, gender, and osteoporosis in distal clavicle fractures. METHODS N = 20 human cadaveric distal clavicles were scanned using XtremeCT with an isometric voxel size of 82 μm. In the sagittal plane, each data set was evaluated in 11 sections of approximately 7 mm thickness. Three topographic regions were defined: the bone lateral to the trapezoid (LTR), intertubercular (ITR), and medial to the conoid (MCR) ligament. Cortical bone mineral density (BMD) [mgHA/cm3] and cortical porosity (1- (BV/TV) [%]) were determined and evaluated relative to age and gender. RESULTS Along the mediolateral axis, there was an >20-fold increase in median cortical porosity (P ≤ .001). There were significant differences in cortical porosity between LTR and ITR (P ≤ .001) but not between ITR and MCR (P = .09). In ITR, cortical porosity was significantly greater in >60-year-old compared to younger donors (P = .01). For BMD, there was an >2-fold decrease toward the distal apex (P ≤ .001). BMD was significantly greater in ITR compared to LTR (P ≤ .001) and in MCR compared to ITR (P = .02). In ITR and MCR, clavicles of >60-year-old donors had significantly lower BMD values compared to younger donors (P 60-year-olds (P > .6). CONCLUSION The distal clavicle features a characteristic bony microarchitecture. The present study revealed a significant difference in bone quality of lateral, intertubercular, and medial zones of the distal clavicle and could specify target areas and strategies for surgical treatment of unstable fractures. Age, gender, and osteoporosis have a limited effect on bone quality and fracture genesis. In contrast, ligamentous quality is supposed to exert a substantial influence on fracture characteristics, especially in ITR. Fracture morphology of the distal clavicle is determined by a bony-ligamentous conjunction, which remains to be characterized

Open reduction and internal fixation of displaced proximal humeral fractures. Does the surgeon's experience have an impact on outcomes?

INTRODUCTION:To evaluate outcomes following open reduction and internal fixation of displaced proximal humeral fractures with regards to the surgeon's experience. MATERIAL AND METHODS:Patients were included undergoing ORIF by use of locking plates for displaced two-part surgical neck type proximal humeral fractures. Reduction and functional outcomes were compared between procedures that were conducted by trauma surgeons [TS], senior (>2 years after board certified) trauma surgeons [STS] and trauma surgeons performing ≥50 shoulder surgeries per year [SS]. Quality of reduction was measured on postoperative x-rays. Functional outcomes were assessed by gender- and age-related Constant Score (nCS). Secondary outcome measures were complication and revision rates. RESULTS:Between 2002-2014 (12.5 years) n = 278 two-part surgical neck type humeral fractures (AO 11-A2, 11-A3) were included. Open reduction and internal fixation was performed with the following educational levels: [TS](n = 68, 25.7%), [STS](n = 110, 41.5%) and [SS](n = 77, 29.1%). Functional outcome (nCS) increased with each higher level of experience and was significantly superior in [SS] (93.3) vs. [TS] (79.6; p = 0.01) vs. [STS] (83.0; p = 0.05). [SS] (7.8%) had significantly less complications compared with [TS] (11.3%; p = 0.003) and [STS](11.7%; p = 0.01) moreover significantly less revision rates (3.9%) vs. [TS](8.2%) and [STS](7.4%) (p<0.001). Primary revision was necessary in 13 cases (4.7%) due to malreduction of the fracture. CONCLUSION:Quality of reduction and functional outcomes following open reduction and internal fixation of displaced two-part surgical neck fractures are related to the surgeon's experience. In addition, complications and revision rates are less frequent if surgery is conducted by a trauma surgeon performing ≥50 shoulder surgeries per year

Supraspinatus Tenotomy in Reverse Shoulder Arthroplasty for Fractures: A Comparative Cohort Study

Background: The aim of this study was to evaluate the functional and radiographic outcome in patients with reverse total shoulder arthroplasty (RSA) for displaced proximal humeral fractures (PHF) with or without tenotomy of the supraspinatus tendon. Methods: Between June 2011 and June 2018, 159 patients (age >65 years) with a displaced proximal humeral fracture underwent reverse total shoulder arthroplasty (Grammont design) in a single-center study and were longitudinally followed up. In all cases, the tuberosities were attached to the prosthesis in a standardized procedure. Functional outcome, range of motion as well as tuberosity integration, resorption and displacement were assessed at final follow-up. Outcomes were compared between patients that underwent RSA in combination with tenotomy of the supraspinatus (ST) and patients that underwent RSA without supraspinatus tenotomy (NT). Results: At a mean follow up of 22.2 ± 16.4 months 76 patients (mean age 77.1 ± 7.2 years, 83% women) could be evaluated (follow-up rate 47.8%). There were no statistically significant differences between the ST (n = 29) and NT groups (n = 47) in tuberosity integration, resorption 20°: 65.5% vs. 14.9%, p 120°: 89.7% vs. 21.3%, p < 0.05). Tuberosity integration (ST and NT together: n = 34) showed better functional results than resorption or displacement (p < 0.05). Conclusions: Tenotomy of the supraspinatus tendon in RSA for displaced PHF leads to similar radiographic results regarding tuberosity integration, resorption and displacement but better functional outcome with regard to range of motion. Level of Evidence: III