Experimental guide wire placement for total shoulder arthroplasty in glenoid models: higher precision for patient-specific aiming guides compared to standard technique without learning curve.

BACKGROUND: Patient-specific aiming devices (PSAD) may improve precision and accuracy of glenoid component positioning in total shoulder arthroplasty, especially in degenerative glenoids. The aim of this study was to compare precision and accuracy of guide wire positioning into different glenoid models using a PSAD versus a standard guide. METHODS: Three experienced shoulder surgeons inserted 2.5 mm K-wires into polyurethane cast glenoid models of type Walch A, B and C (in total 180 models). Every surgeon placed guide wires into 10 glenoids of each type with a standard guide by DePuy Synthes in group (I) and with a PSAD in group (II). Deviation from planned version, inclination and entry point was measured, as well as investigation of a possible learning curve. RESULTS: Maximal deviation in version in B- and C-glenoids in (I) was 20.3° versus 4.8° in (II) (p < 0.001) and in inclination was 20.0° in (I) versus 3.7° in (II) (p < 0.001). For B-glenoid, more than 50% of the guide wires in (I) had a version deviation between 11.9° and 20.3° compared to ≤ 2.2° in (II) (p < 0.001). 50% of B- and C-glenoids in (I) showed a median inclination deviation of 4.6° (0.0°-20.0°; p < 0.001) versus 1.8° (0.0°-4.0°; p < 0.001) in (II). Deviation from the entry point was always less than 5.0 mm when using PSAD compared to a maximum of 7.7 mm with the standard guide and was most pronounced in type C (p < 0.001). CONCLUSION: PSAD enhance precision and accuracy of guide wire placement particularly for deformed B and C type glenoids compared to a standard guide in vitro. There was no learning curve for PSAD. However, findings of this study cannot be directly translated to the clinical reality and require further corroboration.

Postoperative cognitive dysfunction after beach chair positioning compared to supine position in orthopaedic surgery in the elderly.

INTRODUCTION: Postoperative cognitive dysfunction (POCD) occurs in up to 26% of patients older than 60 years 1 week after non-cardiac surgery. Intraoperative beach chair positioning (BCP) is advantageous for some types of shoulder surgery. However, this kind of positioning leads to a downward bound redistribution of blood volume, with possible hypoperfusion of the brain. We hypothesized that patients > 60 years undergoing orthopaedic shoulder surgery in a BCP might experience more POCD than patients operated in the supine position (SP). MATERIAL AND METHODS: A single-centre, prospective observational trial of 114 orthopaedic patients was performed. Study groups were established according to the type of intraoperative positioning. Anaesthesiological management was carried out similarly in both groups, including types of anaesthetics and blood pressure levels. POCD was evaluated using the Trail Making Test, the Letter-Number Span and the Regensburger Word Fluency Test. The frequency of POCD 1 week after surgery was considered primary outcome. RESULTS: Baseline characteristics, including duration of surgery, were comparable in both groups. POCD after 1 week occurred in 10.5% of SP patients and in 21.1% of BCP patients (p = 0.123; hazard ratio 2.0 (CI 95% 0.794-5.038)). After 4 weeks, the incidence of POCD decreased (SP: 8.8% vs. BCP: 5.3%; p = 0.463). 12/18 patients with POCD showed changes in their Word Fluency Tests. Near-infrared spectroscopy (NIRS) values were not lower in patients with POCD compared to those without POCD (54% (50/61) vs. 57% (51/61); p = 0.671). CONCLUSION: POCD at 1 week after surgery tended to occur more often in patients operated in beach chair position compared to patients in supine position without being statistically significant.

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.

Secondary tension pneumothorax in a COVID-19 pneumonia patient: a case report.

PURPOSE: Especially in elderly and multimorbid patients, Coronavirus Disease 2019 (COVID-19) may result in severe pneumonia and secondary complications. Recent studies showed pneumothorax in rare cases, but tension pneumothorax has only been reported once. CASE PRESENTATION: A 47-year-old male was admitted to the emergency department with fever, dry cough and sore throat for the last 14 days as well as acute stenocardia and shortage of breath. Sputum testing (polymerase chain reaction, PCR) confirmed SARS-CoV-2 infection. Initial computed tomography (CT) showed bipulmonary groundglass opacities and consolidations with peripheral distribution. Hospitalization with supportive therapy (azithromycin) as well as non-invasive oxygenation led to a stabilization of the patient. After 5 days, sputum testing was negative and IgA/IgG antibody titres were positive for SARS-CoV-2. The patient was discharged after 7 days. On the 11th day, the patient realized pronounced dyspnoea after coughing and presented to the emergency department again. CT showed a right-sided tension pneumothorax, which was relieved by a chest drain (Buelau) via mini open thoracotomy. Negative pressure therapy resulted in regression of the pneumothorax and the patient was discharged after 9 days of treatment. CONCLUSION: Treating physicians should be aware that COVID-19 patients might develop severe secondary pulmonary complications such as acute tension pneumothorax. LEVEL OF EVIDENCE: V.

Glenohumeral joint lavage does not affect clinical outcomes in open reduction and internal fixation of displaced intracapsular proximal humeral fractures: a prospective, randomized, double-blinded trial.

BACKGROUND: This prospective, randomized, and double-blinded trial evaluates the effect of intraoperative glenohumeral joint lavage in open reduction and internal fixation of displaced intracapsular proximal humeral fractures. METHODS: Between January 2016 and April 2018, 86 patients (mean age: 65.2 ± 16.3 years) with a displaced intracapsular proximal humeral fracture were treated by open reduction and internal fixation using locking plates. Patients were randomized to either locked plating followed by intraoperatively performed glenohumeral joint lavage (group L, n = 36) or locked plating without the lavage (group NL, n = 36). Functional outcome assessment included range of shoulder motion, strength, and the Constant score, obtained 6 weeks, 3 months, 6 months, and 12 months postoperatively. A total of 62 shoulders could be reviewed for final investigation (86% follow-up). RESULTS: One year after open reduction and internal fixation, the mean Constant score was 70 ± 14 (group L, n = 31) compared with 73 ± 14 (group NL, n = 31, P = .272). The mean forward flexion and abduction in group L was 134 ± 33 and 128 ± 33 as compared with 139 ± 32 and 135 ± 32 in group NL, respectively (P = .538, P = .427). The mean external rotation was 40 ± 16 (group L) compared with 44 ± 16 (group NL) (P = .210). The overall complication rate was 9.6% and did not differ significantly between the groups (P = .321). In group L, there were 2 cases of avascular necrosis (6.5%) and 1 case of secondary displacement (3.2%). In group NL, 1 case of avascular necrosis (3.2%) and 1 case of secondary displacement were noted (3.2%, P = .742). CONCLUSION: The results of this study do not demonstrate a need for glenohumeral joint lavage in open reduction and internal fixation of displaced intracapsular proximal humeral fractures with regard to shoulder function at 1-year follow-up.

Screw-tip augmentation versus standard locked plating of displaced proximal humeral fractures: a retrospective comparative cohort study.

BACKGROUND: This study compared the clinical and radiologic outcomes of screw tip-augmented locking plate osteosynthesis vs. standard locked plating in elderly patients with displaced proximal humeral fractures. METHODS: Of the 94 patients older than 65 years with displaced proximal humeral fractures, 55 underwent fixation with a locking plate only whereas 39 underwent fixation using a locking plate with fluoroscopy-controlled polymethyl methacrylate augmentation of screw tips. RESULTS: At 2 years' follow-up, the locking plate-only group showed a mean Constant score (CS) of 62.6 ± 17.4 points, mean CS as a percentage of the uninjured side of 78.2% ± 18.9%, and mean age- and sex-adjusted CS of 72.4 ± 20.5 points. Among the 39 patients who underwent locked plating with polymethyl methacrylate augmentation of screw tips, the mean CS was 63.7 ± 18.5 points (P = .28), the mean CS as a percentage of the uninjured side was 79.5% ± 20.4% (P = .36), and the mean age- and sex-adjusted CS was 76.8 ± 26.2 points (P = .11). The mean Disabilities of the Arm, Shoulder and Hand score was 26.4 ± 21.3 in the locking plate-only group compared with 23.6 ± 19.2 in the group with screw tip-augmented locking plate osteosynthesis (P = .41). The overall complication rate was 16.3% in the locking plate-only group compared with 12.8% in the group with screw tip-augmented osteosynthesis (P = .86); loss of fixation occurred in 10.9% vs. 5.1% (P = .74). The follow-up rate was 81%. CONCLUSIONS: Loss of fixation was less frequent when augmentation of screw tips was performed; however, at the 2-year follow-up, the clinical and radiologic outcomes were not significantly different compared with standard locked plating without augmentation.

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%, 2× labrum repair) and in 3 patients of group 2 (14.3%, of Group 2 (2× arthroscopic cuff repair of full thickness tear, 1× 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.

Preemptive volume therapy to prevent hemodynamic changes caused by the beach chair position: hydroxyethyl starch 130/0.4 versus Ringer's acetate-a controlled randomized trial.

BACKGROUND: Hemodynamic instability frequently occurs in beach chair positioning for surgery, putting patients at risk for cerebral adverse events. This study examined whether preoperative volume loading with crystalloids alone or with a crystalloid-colloid combination can prevent hemodynamic changes that may be causative for unfavorable neurologic outcomes. METHODS: The study randomly assigned 43 adult patients undergoing shoulder surgery to 3 study groups. Each group received an infusion of 500 mL of Ringer's acetate between induction of anesthesia and being placed in the beach chair position. The crystalloid group received an additional bolus of 1000 mL Ringer's acetate. The hydroxyethyl starch group was administered an additional bolus of 500 mL of 6% hydroxyethyl starch 130/0.4. Hemodynamic monitoring was accomplished via an esophageal Doppler probe. Cerebral oxygen saturation was examined with near-infrared spectroscopy. Changes in stroke volume variation between the prone and beach chair positions were defined as the primary outcome parameter. Secondary outcomes were changes in cardiac output and cerebral oxygen saturation. RESULTS: The control group was prematurely stopped after enrollment of 4 patients because of adverse events. In the hydroxyethyl starch group, stroke volume variation remained constant during positioning maneuvers (P = .35), whereas a significant increase was observed in the Ringer's acetate group (P < .01; P = .014 for intergroup comparison). This was also valid for changes in cardiac output. Cerebral oxygen saturation significantly decreased in both groups. CONCLUSIONS: Preprocedural boluses of 500 mL of 6% hydroxyethyl starch 130/0.4 as well as 1000 mL of Ringer's acetate were efficient in preserving hemodynamic conditions during beach chair position.

Diagnostic performance of susceptibility-weighted magnetic resonance imaging for the assessment of sub-coracoacromial spurs causing subacromial impingement syndrome.

OBJECTIVES: To evaluate the potential of susceptibility-weighted-magnetic-resonance-imaging (SWMR) for the detection of sub-coracoacromial spurs in patients with clinically suspected subacromial impingement syndrome (SAIS), compared to standard MR-sequences and radiographs. METHODS: Forty-four patients with suspected SAIS were included. All patients underwent radiography, standard MRI of the shoulder and SWMR. Radiograph-based identification of sub-coracoacromial spurs served as goldstandard. Radiographs identified twenty-three spurs in twenty-three patients. Twenty-one patients without spur formation served as reference group. Detection rate, sensitivity/specificity and interobserver-agreements were calculated. Linear regression was applied to determine the relationship between size measurements on radiographs and MRI. RESULTS: Detection rates for spurs on standard MRI and SWMR were 47.8 % and 91.3 % compared to radiography (p<0.001). SWMR demonstrated a sensitivity of 97.7 % (CI=0.92-1) and a specificity of 91.3 % (CI=0.788-1) for the identification of spurs. Standard MR-sequences achieved a sensitivity of 47.8 % (CI=0.185-0.775) and a specificity of 80.8 % (CI=0.642-0.978). Size measurements between SWMR and radiography showed a good correlation (R2=0.75;p<0.0001), while overestimating lesion size (5.7±1.2 mm; 4.3±1.3 mm;p<0.0001). Interobserver-agreement for spurs was high on SWMR (R2=0.74;p<0.0001), but low on standard MRI (R2=0.24;p<0.0001). CONCLUSIONS: SWMR allows a reliable detection of sub-coracoacromial spur formation in patients with SAIS and is superior to standard MR-sequences using radiography as goldstandard. KEY POINTS: • SWMR has the potential to reliably identify sub-coracoacromial spurs without radiation exposure. • SWMR provides comparable detection rates to conventional radiography for sub-coracoacromial spur formation. • SWMR yields higher detection rates compared to standard-MR regarding sub-coracoacromial spur formation. • SWMR can be implemented in routine shoulder MRI protocols.

Diagnosis of Calcific Tendonitis of the Rotator Cuff by Using Susceptibility-weighted MR Imaging.

PURPOSE: To evaluate the diagnostic performance of susceptibility-weighted imaging (SWI) and standard shoulder joint magnetic resonance (MR) sequences in comparison to that of conventional radiography for the identification of calcifications in the rotator cuff in patients with calcific tendonitis. MATERIALS AND METHODS: The institutional review board approved this prospective study. Written informed consent was obtained from all subjects. Fifty-four patients clinically suspected of having calcific tendonitis of the rotator cuff were included. On radiographs (the standard of reference), 27 patients had positive calcification findings, and 27 did not. Standard MR sequences and SWI, including magnitude and phase imaging, were performed. The diameter of calcifications was measured to assess intermodality correlations. Sensitivity, specificity, and intra- and interobserver agreement were calculated. Phantom measurements were performed to assess the detection limit of SWI. RESULTS: Fifty-six calcifications were detected with radiography in 27 patients. Most (55 calcifications, 98%) could be identified as calcifications by using SWI. Standard T1- and T2-weighted sequences were used to identify 33 calcifications (59%). SWI yielded a sensitivity of 98% (95% confidence interval [CI]: 0.943, 1) and specificity of 96% (95% CI: 0.886, 1) for the identification of calcifications when compared with radiography. Standard rotator cuff MR sequences yielded a sensitivity of 59% (95% CI: 0.422, 0.758) and specificity of 67% (95% CI: 0.493, 0.847). Diameter measurements demonstrated a high correlation between SWI and radiography (R(2) = 0.90), with overestimation of lesion diameter at SWI (mean ± standard deviation for SWI, 7.6 mm ± 5.4; for radiography, 5.3 mm ± 5.1). SWI yielded higher interobserver agreement (R(2) = 0.99, P < .001; 95% CI: 0.989, 0.996) compared with standard MR sequences (R(2) = 0.67, P = .62; 95% CI: 0.703, 0.899). In phantom experiments, SWI and computed tomography were used to identify small calcifications that were missed at radiography. CONCLUSION: SWI enables the reliable detection of calcifications in the rotator cuff in patients with calcific tendonitis by using conventional radiography as a reference and offers better sensitivity and specificity than standard rotator cuff MR sequences.

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

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. TRIAL REGISTRATION: Clinical Trial ( NCT02609906 ), November 18, 2015, registered retrospectively.

Complications of locked plating for proximal humeral fractures-are we getting any better?

BACKGROUND: Complication rates reported after locking plate fixation of proximal humeral fractures still range up to 40%. Whether modifications of surgical techniques, use of primary shoulder arthroplasty, or a fracture-specific management resulted in decreased complication rates during recent years remains unclear. Therefore, the aim of this long-term observation study was to analyze the incidence of complications and revision surgery after locked plating. METHODS: Between February 2002 and December 2013, 788 patients (aged 67.4 ± 17.3 years) with displaced proximal humeral fractures were treated with locking plate, primary hemiarthroplasty (HA), or reverse shoulder arthroplasty (RSA). Standardized follow-up included radiographs at 1 day, 6 weeks, and 3, 6, and 12 months. Complications and unplanned revision surgery were prospectively recorded over the complete follow-up. RESULTS: Of 788 patients, 646 (82%) were treated with locking plate, 82 (10.4%) with HA, and 60 (7.6%) with RSA. Mean follow-up was 14.8 ± 3.8 months. The mean complication rate associated with locked plating was 12.8%, and revision surgery was necessary in 11.6%. Within the last 5 years, the loss of fixation rate markedly decreased from 14.3% to 4.8%; simultaneously, an increased use of RSA was observed. CONCLUSION: The overall complication rate of locking plate osteosynthesis for proximal humeral fractures has been decreasing considerably within the last years. Among others, this might be due to an increased use of primary RSA for complex fracture types. In addition to a precise surgical technique, choosing the adequate treatment for each individual fracture to avoid complications and revision surgery is of utmost importance.

[Distal clavicle fractures. Classifications and management]. / Laterale Klavikulafraktur. Klassifikationen und Therapieoptionen.

BACKGROUND: Fractures of the distal third of the clavicle represent 10-30% of all clavicle fractures . Frequently, these fractures result in instability due to a combination of bony and ligamentous injury. Thus, assessment of the stability is essential for adequate treatment of these fractures. AIM: This article presents a review of the different classification systems for distal clavicle fractures with respect to anatomical and functional factors to allow for comprehensive assessment of stability. Furthermore, the different treatment options for each fracture type are analyzed. RESULTS AND DISCUSSION: Fractures to the distal third of the clavicle without instability can be treated conservatively with satisfactory outcome. In contrast, instability may result in symptomatic non-union under conservative treatment; therefore, distal clavicle fractures with instability should be treated operatively with respect to the functional demands of the patient. Operative treatment with locked plating in combination with coracoclavicular fixation results in excellent functional results. Arthroscopically assisted fracture fixation may be beneficial in terms of a minimally invasive approach as well as assessment and treatment of associated glenohumeral lesions.

Long-term functional outcomes (median 10 years) after locked plating for displaced fractures of the proximal humerus.

BACKGROUND: Locked plating has become an accepted treatment for displaced fractures of the proximal humerus. However, to our knowledge, long-term outcomes have not been reported. METHODS: Between February 2002 and March 2004, 121 patients with displaced proximal humeral fractures were treated by open reduction and locking plate fixation. Forty-three patients were available for 10-year (95% confidence interval [CI], 9.8-10.1) follow-up, including Constant score (CS), Disabilities of the Arm, Shoulder and Hand score, and Short Form 36 questionnaire. RESULTS: Of 43 patients (72% women; mean age at time of fracture repair, 58.2 years; 95% CI, 54.2-62.2), the absolute CS 10 years after surgery was 75.3 (95% CI, 69.2-81.4). The normalized CS was 88.4 (95% CI, 81.7-95.1), and the CS in percentage to the contralateral side (%CS) was 83.7 (95% CI, 78.5-88.9). In contrast, at 1 year, the CS was 73.9 (95% CI, 67.8-80.2, P = .774), the normalized CS was 87.2 (95% CI, 80.4-94.0; P = .765), and the %CS was 78.7 (95% CI, 71.5-85.8; P = .355). The CS at 10 years correlated with the CS at 1 year after surgery (r = 0.460; P < .01) and with patient gender (r = -0.424; P < .01), and it strongly correlated with patient age (r = -0.545; P < .001). CONCLUSIONS: Ten years after locked plating of displaced proximal humeral fractures, patients show good to excellent outcomes in the majority of cases with no relevant decline compared with the shoulder function 1 year after surgery. However, poor long-term outcome is seen in 16% of patients and relates to a low CS 1 year after surgery. Thus, patients developing poor long-term outcomes may be identified at an earlier stage.

Position of polyaxial versus monoaxial screws in locked plating for proximal humeral fractures: analysis of a prospective randomized study.

BACKGROUND: Aim of the study was to compare the chosen position of polyaxial locking screws with the position of monoaxial screws in the humeral head of proximal humeral fractures treated by locked plating. METHODS: In a prospective randomized observational study, 124 consecutive patients (mean age 70.9±14.8 years) sustaining a displaced proximal humeral fracture were treated with either monoaxial or polyaxial screw-inserted locking plate fixation. The chosen positions of locking screws were identified from standardized postoperative radiographs in anteroposterior and outlet-view, with regard to a regional mapping of the humeral head. RESULTS: In monoaxial locking technique, a mean of 6 screws purchased the humeral head (95% CI 5.1-6.2), and in polyaxial locking technique, a mean of 4 screws (95% CI 3.3-4.5), respectively. Screws were placed in the regions superolateral: monoaxial 24.8%, polyaxial 20.7% (p=0.49); superomedial: monoaxial 21.9%, polyaxial 20.0% (p=0.433); inferolateral: monoaxial 32.5%, polyaxial 35.0% (p=0.354); inferomedial: monoaxial 20.8%, polyaxial 24.2% (p=0.07), superoposterior: monoaxial 45.5%, polyaxial 30.8% (p=0.57); superoanterior: monoaxial 4.4%, polyaxial 8.3% (p=0.33); inferoposterior: monoaxial 22.5%, polyaxial 29.8% (p=0.49) and inferoanterior: monoaxial 27.5%, polyaxial: 31.2% (p=0.09). CONCLUSION: The chosen screws' position in monoaxial and polyaxial locking plate fixation of displaced proximal humeral fractures do not differ significantly. However, loss of fixation is observed more frequently if the fixation did not include at least one screw within the superoposterior region of the humeral head, suggesting that a screw purchasing the superoposterior region is beneficial in locked plating of proximal humeral fractures. LEVEL OF EVIDENCE: Treatment Study, Level II.

Detailed analysis of surgically treated hand trauma patients in a regional German trauma centre.

Hand and forearm injuries are the most frequent reason for consultations in German emergency departments. Therefore, full recovery has a high social and economic relevance. In this study, data on surgically treated hand injuries in a regional German trauma centre between 01.01.2019 and 31.01.2021 were collected using the new German HandTraumaRegister of the German Society for Hand Surgery. These data were retrospectively analysed and correlated with mobility data of the Bavarian population, the 7-day incidence of Covid-19 infections in Germany and the number of elective hand surgeries. We found that a fall from standing height with consecutive distal radius fracture was the most common injury in women, whereas mechanism of injury and diagnosis were more diverse in men. The populations' mobility correlated well with the number of accidents, which in turn was reciprocal to the 7-day-incidence of Covid-19 infections. The number of elective hand surgeries expectedly dropped significantly during the state-imposed lockdowns. Knowing that mainly young men and elderly women suffer from hand injuries, tailored prevention measures may be elaborated. In order to reduce socioeconomic burden, care for hand injuries and elective hand surgeries must be guaranteed according to the frequency of their occurrence.

It Is Always the Same-A Complication Classification following Angular Stable Plating of Proximal Humeral Fractures.

INTRODUCTION: The aim of this study was to create a novel complication classification for osteosynthesis-related complications following angular stable plating of the proximal humerus subsuming the influence of these complications on clinical outcome in relation to fracture morphology and consequent revision strategies. A total of 1047 proximal humerus fractures with overall 193 osteosynthesis-associated complications (24.5%) were included. The following complication types could be clarified: complication Type 1 is defined by mild varus (<20°) or valgus displacement of the humeral head without resulting in a screw cutout through the humeral head cortex. Type 2a is defined by varus displacement (<20°) of the humeral head associated with screw cutout through the humeral head cortex. Type 2b complication is limited to displacement of the greater tuberosity, lesser tuberosity, or both tuberosities. Complication Type 2c is defined by severe varus dislocation (>20°) of the humeral head with screw cutout at the humeral head cortex. Complication Type 3 describes a displacement of the angular stable plate in the humeral shaft region with associated shaft-sided screw cutout, while the position of the humeral head remains static. Complication Type 4 is characterized by the occurrence of AVN with or without glenoidal affection (4a/b). Clinical outcome according to the constant score was mainly affected by type 2-4, leading to a deteriorated result. Depending on the type of complication, specific revision strategies can be considered. Additionally, more complex fracture patterns fostered the incidence of complications.

Mid-term functional outcome (minimum 24 months, mean 4 years) after locking plate osteosynthesis for displaced fractures of the proximal humerus in 557 cases.

BACKGROUND: The best surgical management of displaced proximal humeral fractures remains a matter of considerable debate. This study presents mid-term functional outcome (median 4 years) after locking plate osteosynthesis for displaced proximal humeral fractures. METHODS: Between February 2002 and December 2014 1031 patients with 1047 displaced proximal humeral fractures were treated by open reduction and locking plate fixation with the same implant and received consecutive prospective follow up at least 24 months after surgical treatment. Clinical follow-up consisted of Constant Murley score (CS), Disabilities of the Arm, Shoulder and Hand score (DASH), and Short Form 36 questionnaire (SF-36). Complete follow-up could be performed in 557 (53.2%) cases, with a mean follow-up of 4.0 ± 2.7 years. RESULTS: Of 557 patients (67% women; mean age at time of osteosynthesis: 68.3 ± 15.5 years) absolute CS of all patients 4 ± 2.7 years after surgery was 68.4 ± 20.3 points. Normalized CS according to Katolik was 80.4 ± 23.8 points, and CS in percentage to the contralateral side (%CS) was 87.2 ± 27.9%. DASH score was at 23.8 ± 20.8 points. Osteosynthesis related complications (secondary displacement, screw cutout, avascular necrosis (n = 117 patients) were associated with lower functional scores (mean CS was 54.5 ± 19.0 p.; nCS 64.5 ± 22.9 p.;%CS 71.2 ± 25.0%; DASH score 31.9 ± 22.4 p.). The SF 36 was 66.5 points in the case cohort and a vitality mean of 69.4 points. Patients with a complication showed lower results (SF 36 56.7; vitality mean 64.9 points). CONCLUSIONS: Overall, patients following locking plate osteosynthesis of displaced proximal humeral fractures showed good to moderate outcomes four years after surgery. Mid-term functional outcomes correlate significantly with those at 1 year postoperatively. Furthermore, there is a significant negative correlation of midterm functional outcome with the occurrence of complications. LEVEL OF EVIDENCE: Level III, prospective nonconsecutive patients.

Fibrocartilage in various regions of the human glenoid labrum. An immunohistochemical study on human cadavers.

PURPOSE: The nature and the distribution of fibrocartilage at the human glenoid labrum are unclear, and a better understanding may help to restore its function in open and arthroscopic Bankart repair. Aim of this study was to describe the fibrocartilage extent within the labrum at clinically relevant sites of the glenoid in order to relate the molecular composition of the labrum to its mechanical environment. METHODS: Twelve fresh frozen human cadaveric shoulders (mean age 38 years) were obtained, and sections perpendicular to the glenoid rim at the 12, 2, 3, 4, 6 and 9 o' clock position were labelled with antibodies against collagen I and II, aggrecan and link protein. RESULTS: A fibrocartilaginous transition zone with a characteristic collagen fibre orientation was found in 81% of cases, evenly distributed (83-92%) around the glenoid rim. The percentage of labrum cross-sectional area comprised of fibrocartilage averaged 28% and ranged from 26% at 12 o'clock on the glenoid clock face to 30% at 3 o'clock. The highest amount of fibrocartilage (82%) was found in the region neighbouring the hyaline articular cartilage. In the region beyond the bony edge of the glenoid, fibrocartilage cross-sectional area did not exceed 12-17%. CONCLUSION: Fibrocartilage is present at all examined positions around the glenoid rim and constitutes up to 1/3 of the cross-sectional area of the labrum. In turn, the percentage of fibrocartilage in different regions of its cross-section varies considerably. The findings suggest that the penetration of fibrocartilaginous tissue may be reduced by avoiding the highly fibrocartilage transition zone during restoration of labral detachment.