Open plate fixation in displaced pediatric proximal humerus fractures is safe and leads to very good functional outcomes.

INTRODUCTION: In displaced pediatric proximal humerus fractures (PHF), surgical treatment ranges from closed to open procedures. Soft tissue interposition can impede closed reduction, making open techniques necessary. While K-wire fixation and elastic stable intramedullary nailing (ESIN) lead to good results, plate fixation could be an alternative in patients with limited growth potential and highly unstable or insufficiently retained fractures. Only few studies with low sample sizes have assessed plate fixation, yet. In this study, the outcome of pediatric PHFs treated with plate fixation was evaluated. MATERIALS AND METHODS: We present a retrospective case series of 18 patients with open growth plates and unilateral, displaced PHFs, treated with plate fixation. The mean age at trauma was 12.1 years (± 2.4), the mean follow-up was 6.52 years (± 4.37). A mean fracture angulation of 32.3° (± 10.89°) was seen. Postoperative assessments included range of motion, clinical scores [Simple Shoulder Test (SST), Subjective Shoulder Value (SSV), American Shoulder and Elbow Surgeons (ASES) Shoulder Score, Pediatric/Adolescent Shoulder Score (PASS), Disabilities of Arm, Shoulder and Hand (DASH) Score], radiological parameters and subjective satisfaction. RESULTS: All patients showed excellent results in SST (99.4% ± 0.02), SSV (98.3% ± 0.04), ASES-score (100% ± 0) and PASS (0.99 ± 0.01). In the DASH-score, 17 patients had excellent results, one patient showed a good outcome. Fracture healing occurred in all patients without complications. Eight patients complained about bothering scars. Age, gender and fracture morphology did not affect the outcome. Revision surgery after secondary fracture dislocation did not show a worsened outcome compared to primary plate fixation. Physeal growth plate bridging implants did not worsen the outcome. The timing of implant removal within the first 6 months postoperatively did not affect long-term function. CONCLUSION: Plate fixation is a safe option in pediatric patients with limited growth potential and highly displaced PHFs. Plate fixation led to a good to excellent functional outcome, regardless of fracture morphology and implant positioning. A higher invasiveness and the need for implant removal must be considered.

Conservative Versus Operative Treatment of Proximal Humerus Fractures in Older Individuals­an Analysis of Insurance Data.

BACKGROUND: Little is known about the frequency and results of conservative treatment of proximal humerus fractures in older individuals. METHODS: Billing data of the BARMER health insurance carrier for all patients of age 65 and above with proximal humerus fractures in the years 2005-2021 were retrospectively analyzed with multivariable Cox regression models, taking account of the patients' age, sex, and comorbidity profiles. The defined primary endpoints were overall survival (OS), major adverse events (MAE), thromboembolic events (TE), and complications of surgery or of trauma. Multivariable p values for the effect of treatment on all primary endpoints were jointly adjusted with the Bonferroni-Holm method. RESULTS: 54% of 81 909 patients were treated conservatively. Conservative treatment was more common in those who received their diagnosis as outpatients (79.5%, vs. 37.2% for inpatients). Operative treatment was associated with significantly longer overall survival (long-term HR 0.89, 95% confidence interval [0,86; 0,91]) and fewer MAE (0.90; [0.88; 0.92]) and TE (0.89; [0.87; 0.92]), but more complications due to surgery or trauma (1.66; [1,.4; 1.78]; all p < 0.001). 3.1% of the patients who had been initially treated conservatively underwent surgery within 6 months of their diagnosis. Risk factors for the failure of conservative treatment included alcohol abuse, obesity, cancer, diabetes mellitus, Parkinson disease, and osteoporosis. CONCLUSION: The conservative treatment of proximal humerus fracture is associated with a lower overall rate of complications due to surgery or trauma, but also with more MAE and TE and higher overall mortality. These findings underline the need for individualized and risk-adjusted treatment recommendations.

The Long Head of the Biceps Has a Stabilizing Effect on the Glenohumeral Joint in Simulated Infraspinatus or Subscapularis but Not Supraspinatus Rotator Cuff Deficiency: A Biomechanical Study.

PURPOSE: To investigate the stabilizing role of the long head of the biceps (LHB) for different simulated rotator cuff (RC) tears. METHODS: Human cadaveric specimens (n = 8) were fixed in a robotic-based experimental setup with a static loading of the RC, deltoid, and the LHB. RC tears were simulated by unloading of the corresponding muscles. A throwing motion and an anterior load-and-shift test were simulated under different RC conditions by unloading the supraspinatus (SS), subscapularis (SSc), infraspinatus (IS), and combinations (SS + SSc, SS + IS, SS + SSc + IS). The LHB was tested in 3 conditions: unloaded, loaded, and tenotomy. Translation of the humeral head and anterior forces depending on loading of the RC and the LHB was captured. RESULTS: Loading of LHB produced no significant changes in anterior force or glenohumeral translation for the intact RC or a simulated SS tear. However, if SSc or IS were unloaded, LHB loading resulted in a significant increase of anterior force ranging from 3.9 N (P = .013, SSc unloaded) to 5.2 N (P = .001, simulated massive tear) and glenohumeral translation ranging from 2.4 mm (P = .0078, SSc unloaded) to 7.4 mm (P = .0078, simulated massive tear) compared to the unloaded LHB. Tenotomy of the LHB led to a significant increase in glenohumeral translation compared to the unloaded LHB in case of combined SS + SSc (2.6 mm, P = .0391) and simulated massive tears of all SS + SSc + IS (4.6 mm, P = .0078). Highest translation was observed in simulated massive tears between loaded LHB and tenotomy (8.1 mm, P = .0078). CONCLUSIONS: Once SSc or IS is simulated to be torn, the LHB has a stabilizing effect for the glenohumeral joint and counteracts humeral translation. With a fully loaded RC, LHB loading has no influence. CLINICAL RELEVANCE: With an intact RC, the condition of the LHB showed no biomechanical effect on the joint stability. Therefore, from a biomechanical point of view, the LHB could be removed from the joint when the RC is intact or reconstructable. However, since there was a positive effect even of the unloaded LHB in this study when SSc or IS is deficient, techniques with preservation of the supraglenoid LHB origin may be of benefit in such cases.

Medial migration of the helical blade with penetration into the acetabulum: a rare complication using the TFNA nail.

PURPOSE: To determine the frequency and possible reasons of medial migration with penetration into the acetabulum (MMPA) of the helical blade when using the Trochanteric Fixation Nail Advanced (TFNA) is used for treatment of pertrochanteric fractures. METHODS: All patients with pertrochanteric femoral fracture, treated by intramedullary femoral nailing with the TFNA, were retrospectively reviewed for MMPA of the helical blade. Epidemiological parameters, additional procedures, distance of medial migration, time from primary operation to revision as well as type of revision were assessed. RESULTS: 4 of 153 patients treated with the TFNA developed an MMPA of the helical blade (risk = 2.6%), with a mean medial migration of the blade of 11.6 mm (SD 8.8). The mean time from initial operation to revision surgery was 70 days (SD 30). All patients were revised by conversion to cemented total hip arthroplasty. CONCLUSION: MMPA of the helical blade is a rare but potentially hazardous complication of femoral nailing with the TFNA femoral nail, resulting in the necessity for revision surgery and total hip arthroplasty.

Treatment Reality of Proximal Humeral Fractures in the Elderly-Trending Variants of Locking Plate Fixation in Germany.

BACKGROUND: The surgical treatment of proximal humeral fractures (PHFs) with locking plate fixation (LPF) in the elderly is associated with high complication rates, especially in osteoporotic bone. Variants of LPF such as additional cerclages, double plating, bone grafting and cement augmentation can be applied. The objective of the study was to describe the extent of their actual use and how this changed over time. METHODS: Retrospective analysis of health claims data of the Federal Association of the Local Health Insurance Funds was performed, covering all patients aged 65 years and older, who had a coded diagnosis of PHF and were treated with LPF between 2010 and 2018. Differences between treatment variants were analyzed (explorative) via chi-squared or Kruskal-Wallis tests. RESULTS: Of the 41,216 treated patients, 32,952 (80%) were treated with LPF only, 5572 (14%) received additional screws or plates, 1983 (5%) received additional augmentations and 709 (2%) received a combination of both. During the study period, relative changes were observed as follows: -35% for LPF only, +58% for LPF with additional fracture fixation and +25% for LPF with additional augmentation. Overall, the intra-hospital complication rate was 15% with differences between the treatment variants (LPF only 15%, LPF with additional fracture fixation 14%, LPF with additional augmentation 19%; p < 0.001), and a 30-day mortality of 2%. CONCLUSIONS: Within an overall decrease of LPF by approximately one-third, there is both an absolute and relative increase of treatment variants. Collectively, they account for 20% of all coded LPFs, which might indicate more personalized treatment pathways. The leading variant was additional fracture fixation using cerclages.

[Severe injury type procedures-Influence of the cipher 11 "complications" and the COVID-19 pandemic on a center for maximum care of severe injuries]. / Schwerstverletzungsartenverfahren ­ Einfluss der Ziffer 11 "Komplikationen" sowie der COVID-19-Pandemie auf ein Haus der traumatologischen Maximalversorgung.

INTRODUCTION: Ensuring the best treatment options for injured patients (healing process, Heilverfahren, HV) is the main goal and responsibility of the German statutory accident insurance (DGUV). The injury type catalogue is the tool to guide the HV. The development of the number of cases treated in a center for severe injury type procedures, the effects of the cipher 11 "complications" of the catalogue and the effects of the COVID-19 pandemic are presented. METHODS: A retrospective study of all patients treated in the context of the DGUV from January 2019 to December 2021 was carried out. The number of cases before and during the legal lockdown actions were compared. The case mix index, the mean number of operations, the mean time in the operating room and the hospital stay were analyzed. Additionally, the cases under the cipher 11 were classified according to the specific anatomical regions. RESULTS: Out of 2007 cases 67% were classified as severe injury type procedures (SAV). Of these cases 51% were categorized to the cipher 11 of the injury type catalogue. Complications were observed particularly in the anatomical regions of the shoulder girdle, elbow, hand, knee, ankle joint and foot. These complex cases are economically not sufficiently represented. During the governmental COVID-19 lockdown actions, the number of patients treated in the context of the DGUV significantly decreased. CONCLUSION: The injury type catalogue is used effectively in the catchment area of the present trauma center. Most of the cases treated in the present trauma center are severe injury type procedures; however, more than half of these cases are classified as complications. This development might show the need for a structural change or an adjustment of the HV. The current comments on the injury type catalogue offer important definitions and specifications; however, the conciseness of the entire catalogue should be maintained.

Increased complication rates of salvage reverse total shoulder arthroplasty (RTSA) after failed locked plate fixation compared with primary RTSA in the treatment of proximal humeral fractures in elderly patients.

HYPOTHESIS: Common surgical treatment options for proximal humeral fractures in elderly patients include locked plate fixation (LPF) and reverse total shoulder arthroplasty (RTSA). It was hypothesized that secondary RTSA after LPF would be associated with higher complication rates and costs compared with primary RTSA. METHODS: We analyzed the health insurance data of patients aged ≥65 years who received RTSA for the treatment of a proximal humeral fracture between January 2013 and September 2019 with a pre-study phase of 5 years. Multivariable Cox, logistic, and linear regression models were used to evaluate the association between treatment group and complications, hospital length of stay, charges, and mortality rate during a 34-month follow-up period. RESULTS: A total of 14,220 patients underwent primary RTSA and 1282 patients underwent secondary RTSA after prior surgery using LPF for the treatment of proximal humeral fractures. After adjustment for patient characteristics, more surgical complications were observed after secondary RTSA during index hospitalization (odds ratio, 4.62; 95% confidence interval [CI], 4.00-5.34; P < .001) and long-term follow-up (hazard ratio, 1.52; 95% CI, 1.27-1.81; P < .001). Moreover, secondary RTSA was associated with an increased cumulative total cost of €6638.1 (95% CI, €6229.9-€7046.5; P < .001). If conversion from LPF to secondary RTSA occurred during index hospitalization, more major adverse events, more thromboembolic events, and a higher mortality rate were found in the short and long term (all P < .05). CONCLUSION: Secondary RTSA is associated with higher total costs and more complications. Hence, if surgical treatment of a proximal humeral fracture in an elderly patient is needed, prognostic factors for LPF need to be evaluated carefully. If in doubt, the surgeon should opt to perform primary RTSA as patients will benefit in the long term.

Acromioclavicular and coracoclavicular ligamentous insertion distances depend on the scapular tilt and decrease with anterior direction of the inferior scapula angle.

PURPOSE: A variety of reconstruction techniques exist for the operative treatment of a ruptured acromioclavicular and coracoclavicular ligamentous complex. However, the complication rate remains high; between 5 and 89%. The intraoperative distance between the clavicle, acromion and coracoid is important for the refixation quality. In this study, the influence of scapular deflection on coracoclavicular and acromioclavicular distances was analysed. METHODS: The ligamentous insertions of 24 fresh-frozen human scapulae were exposed. The coracoclavicular and acromioclavicular ligaments were referenced and captured in a rigid body system using a three-dimensional (3D) measurement arm. The inferior angle of the scapula was manually pulled into maximum anterior and posterior deflection, simulating a patient positioning with or without dorsal scapular support, respectively. Based on the rigid body system, the distances between the ligamentous insertions were calculated. Statistical evaluation was performed by setting the distances in anterior deflection to 100% and considering the other distances relative to this position. RESULTS: The scapular deflection had a considerable impact on the distance between the ligamentous insertions. Concerning the conoid ligament, the mean distance was almost doubled when the inferior angle pointed posteriorly compared to anterior deflection (195.3 vs 100.0%; p = 0.028). The insertion of the acromioclavicular capsule also showed a significant association with the direction of deflection (posterior = 116.1% vs. anterior = 100%; p = 0.008). CONCLUSION: Dorsal support shifting the inferior angle of the scapula anteriorly reduces the distance between the ligamentous insertions. Therefore, a patient position on a shoulder table with posterior support of the scapula is recommended to reliability reduce the acromioclavicular joint.

COVID-19 rapid molecular point-of-care testing is effective and cost-beneficial for the acute care of trauma patients.

PURPOSE: To evaluate the accuracy and cost benefit of a rapid molecular point-of-care testing (POCT) device detecting COVID-19 within a traumatological emergency department. BACKGROUND: Despite continuous withdrawal of COVID-19 restrictions, hospitals will remain particularly vulnerable to local outbreaks which is reflected by a higher institution-specific basic reproduction rate. Patients admitted to the emergency department with unknown COVID-19 infection status due to a- or oligosymptomatic COVID-19 infection put other patients and health care workers at risk, while fast diagnosis and treatment is necessary. Delayed testing results in additional costs to the health care system. METHODS: From the 8th of April 2021 until 31st of December 2021, all patients admitted to the emergency department were tested with routine RT-PCR and rapid molecular POCT device (Abbott ID NOW™ COVID-19). COVID-19-related additional costs for patients admitted via shock room or emergency department were calculated based on internal cost allocations. RESULTS: 1133 rapid molecular tests resulted in a sensitivity of 83.3% (95% CI 35.9-99.6%), specificity of 99.8% (95% CI 99.4-100%), a positive predictive value of 71.4% (95% CI 29-96.3%) and a negative predictive value of 99.9% (95% CI 99.5-100%) as compared to RT-PCR. Without rapid COVID-19 testing, each emergency department and shock room admission with subsequent surgery showed additional direct costs of 2631.25€, without surgery of 729.01€. CONCLUSION: Although rapid molecular COVID-19 testing can initially be more expensive than RT-PCR, subsequent cost savings, improved workflows and workforce protection outweigh this effect by far. The data of this study support the use of a rapid molecular POCT device in a traumatological emergency department.

Double plating is associated with higher fixation strength than single plating in osteoporotic fractures of the scapular spine: a biomechanical study.

INTRODUCTION: The number of atraumatic stress fractures of the scapular spine associated with reverse shoulder arthroplasty is increasing. At present, there is no consensus regarding the optimal treatment strategy. Due to the already weakened bone, fractures of the scapular spine require a high fixation stability. Higher fixation strength may be achieved by double plating. The aim of this study was to evaluate the biomechanical principles of double plating in comparison to single plating for scapular spine fractures. METHODS: In this study, eight pairs (n = 16) of human shoulders were randomised pairwise into two groups. After an osteotomy at the level of the spinoglenoid notch, one side of each pair received fracture fixation with a single 3.5 LCP (Locking Compression Plate) plate. The contralateral scapular spine was fixed with a 3.5 LCP and an additional 2.7 LCP plate in 90-90 configuration. The biomechanical test protocol consisted of 700 cycles of dynamic loading and a load-to-failure test with a servohydraulic testing machine. Failure was defined as macroscopic catastrophic failure (screw cut-out, plate breakage). The focus was set on the results of specimens with osteoporotic bone quality. RESULTS: In specimens with an osteoporotic bone mineral density (BMD; n = 12), the mean failure load was significantly higher for the double plate group compared to single plating (471 N vs. 328 N; p = 0.029). Analysis of all specimens (n = 16) including four specimens without osteoporotic BMD revealed no significant differences regarding stiffness and failure load (p > 0.05). CONCLUSION: Double plating may provide higher fixation strength in osteoporotic bone in comparison to a single plate alone. This finding is of particular relevance for fixation of scapular spine fractures following reverse shoulder arthroplasty. LEVEL OF EVIDENCE: Controlled laboratory study.

The Surgical Treatment of Proximal Humeral Fractures in Elderly Patients.

BACKGROUND: The goal of this study is to compare mortality, major adverse events, and complication rates after the surgical treatment of proximal humeral fractures with locked plate fixation (LPF) versus reverse total shoulder arthroplasty (RTSA) in elderly patients. METHODS: Health insurance data from patients aged 65 and above for the period January 2010 to September 2018 were retrospectively evaluated. The median follow-up duration after LPF (40 419 patients) or RTSA (13 552 patients) was 52 months. Hazard ratios adapted to the patients' risk profiles were determined with the aid of multivariable Cox regression models. The p-values were adjusted using the Bonferroni-Holm method. RESULTS: After adaptation to the patients' risk profiles, reverse shoulder replacement showed statistically significantly lower mortality (HR 0.92, 95% confidence interval [0.88; 0.95]; p <0.001) and fewer major adverse events (HR 0.92 [0.89; 0.95]; p<0.001). Eight years after surgery, the risk of surgical complications was twice as high for LPF (12.2% [11.9; 12.7]; HR for RTSA versus LPF 0.5 [0.46; 0.55]; p<0.001 for both), with 3.8% [3.6; 4.0] of the patients receiving a secondary RTSA. Surgical complications were more common (p<0.05) in patients with a diagnosis of osteo - porosis, obesity, alcohol abuse, chronic polyarthritis, or frozen shoulder. CONCLUSION: The long-term findings are in agreement with clinical short-term findings from other studies and support the current trend toward more liberal use of reverse shoulder replacements in elderly patients.

Biomechanical Value of a Protective Proximal Humeral Cerclage in Reverse Total Shoulder Arthroplasty.

Reverse shoulder arthroplasty (RSA) is a commonly performed salvage procedure for failed proximal humeral fracture fixation. The rate of intraoperative periprosthetic fractures is higher compared to primary RSA. The goal of this study was to investigate the biomechanical value of a protective cerclage during stem impaction in a revision surgery setting. Twenty-eight fresh-frozen human humeri were used to assess different configurations for steel wire and FiberTape cerclages. A custom-built biomechanical test setup simulated the mallet strikes during the stem impaction process with the Univers Revers prothesis stem. The mallet energy until the occurrence of a first crack was not different between groups. The total energy until progression of the fracture distally to the cerclage was significantly higher in the cerclage groups compared to the native humerus (9.5 J vs. 3.5 J, respectively; p = 0.0125). There was no difference between the steel wire and FiberTape groups (11.4 J vs. 8.6 J, respectively; p = 0.2695). All fractures were located at the concave side of the stem at the metaphyseal calcar region. This study demonstrates that a protective cerclage can successfully delay the occurrence of a fracture during stem impaction in reverse shoulder arthroplasty. A FiberTape cerclage is biomechanically equally efficient compared to a steel wire cerclage.

[Influence of complications and comorbidities on length of hospital stay and costs for surgical treatment of proximal humeral fractures]. / Einfluss von Komplikationen und Komorbiditäten auf Liegedauer und Kosten bei der operativen Behandlung der proximalen Humerusfraktur.

After a proximal humeral fracture in older patients, locked plate fixation and reverse total shoulder arthroplasty are two competing surgical procedures. Even if recent clinical studies indicate a functional superiority of reverse shoulder arthroplasty over locked plate fixation, health-economic comparative data are lacking in the literature. Health claims data of 55,070 patients aged 65 years or older who were treated with reverse total shoulder arthroplasty or locked plate fixation after proximal humeral fractures, were analyzed regarding length of hospital stay and costs. Multivariable linear regression models were used to analyze the influence of comorbidities and complications on the length of hospital stay and costs. The length of hospital stay after reverse total shoulder arthroplasty with 20.0 days (±13.5 days) was statistically noticeable longer compared to locked plate fixation with 14.6 days (±11.4 days, p < 0.001). The costs per case showed a clear difference with 11,165.70€ (±5884.36€) for reverse total shoulder arthroplasty and 7030.11€ (±5532.02€) for locked plate fixation (p < 0.001). Statistically noticeable cost increases due to comorbidities and complications underline the urgent need for specialized geriatric trauma centers.

Promising Mid-Term Outcomes after Humeral Head Preserving Surgery of Posterior Fracture Dislocations of the Proximal Humerus.

BACKGROUND: The aim of this study was to evaluate the clinical outcome after humeral head preserving surgical treatment of posterior fracture dislocations of the proximal humerus. METHODS: Patients with a posterior fracture dislocation of the proximal humerus that were operatively treated in two level-1 trauma centers within a timeframe of 8 years were identified. With a minimum follow-up of 2 years, patients with humeral head preserving surgical treatment were invited for examination. RESULTS: 19/24 fractures (79.2%; mean age 43 years) were examined with a mean follow-up of 4.1 ± 2.1 years. Of these, 12 fractures were categorized as posteriorly dislocated impression type fractures, and 7 fractures as posteriorly dislocated surgical neck fractures. Most impression type fractures were treated by open reduction, allo- or autograft impaction and screw fixation (n = 11), while most surgical neck fractures were treated with locked plating (n = 6). Patients with impression type fractures showed significantly better ASES scores (p = 0.041), Simple Shoulder Test scores (p = 0.003), Rowe scores (p = 0.013) and WOSI scores (p = 0.023), when compared to posteriorly dislocated surgical neck fractures. Range of motion was good to excellent for both groups with no significant difference. CONCLUSIONS: This mid-term follow-up study reports good to very good clinical results for humeral head preserving treatment.

Male Sex Is Associated with Higher Mortality and Increased Risk for Complications after Surgical Treatment of Proximal Humeral Fractures.

AIMS: The best surgical treatment of multi-fragmentary proximal humeral fractures in the elderly is a highly controversial topic. The aim of this study is to assess for sex-related differences regarding mortality and complications after reverse total shoulder arthroplasty (RTSA) and locking plate fixation (LPF). PATIENTS AND METHODS: All patients from the largest German healthcare insurance (26.5 million policy holders) above the age of 65 years that were treated with LPF or RTSA after a multi-fragmentary proximal humerus fracture between January 2010 and September 2018 were included. Multivariable Cox regression models were used to assess the association of sex with overall survival, major adverse events and surgical complications. RESULTS: A total of 8264 (15%) men and 45,707 (85%) women were followed up for a median time of 52 months. After 8 years, male patients showed significantly higher rates for death (65.8%; 95% CI 63.9-67.5% vs. 51.1%; 95% CI 50.3-51.9%; p < 0.001) and major adverse events (75.5%; 95% CI 73.8-77.1% vs. 61.7%; 95% CI 60.9-62.5%; p < 0.001). With regard to surgical complications, after adjustment of patient risk profiles, there were no differences between females and males after LPF (p > 0.05), whereas men showed a significantly increased risk after RTSA (HR 1.86; 95% CI 1.56-2.22; p < 0.001) with more revision surgeries performed (HR 1.76, 95% CI 1.46-2.12; p < 0.001) compared to women. CONCLUSION: The male sex is an independent risk factor for death and major adverse events after both LPF and RTSA. An increased risk for surgical complications after RTSA suggests that male patients benefit more from LPF. Sex should be considered before making treatment decisions.

Influence of Radiographic Parameters on Reduction of the Critical Shoulder Angle With Arthroscopic Lateral Acromioplasty-A Mathematical Model.

OBJECTIVES: To develop a mathematical model for the preoperative planning of arthroscopic lateral acromioplasty (ALA) and to evaluate the role of radiographic parameters with regards to the critical shoulder angle (CSA). METHODS: Anteroposterior (AP) radiographs of patients who underwent rotator cuff surgery were screened to identify true AP radiographs. Radiographs were assessed for (1) native CSA, (2) CSA after simulated resection of a spur if present, (3) amount of ALA necessary to achieve a CSA of 34°, (4) CSA after 5-mm ALA, (5) lateral acromion angle, (6) acromion index, and (7) sclerosis of the greater tuberosity. RESULTS: A total of 1191 radiographs were screened. Of the 124 patients included, the native CSA was large (≥35°) in 56 patients (45%). In 30 patients (24%), a subacromial spur was detected and resection reduced the CSA by a median of 2°. Spur resection alone reduced the CSA to ≤34° in 19 patients (15.3%). Mean amount of ALA to achieve a CSA of 34° was 3.9 ± 1.8 mm, and this value strongly correlated with the CSA before ALA (R = 0.88, P < .001). The linear regression model to determine the amount of ALA to achieve a CSA of 34° was as follows: R e q u i r e d A L A i n m m = - 39.120 + 1.165 ∗ C S A n a t i v e The multiple R2 for this model was 0.777. Mean reduction of CSA by 5-mm ALA was 3.8 ± 0.8° and 75% of large CSAs were reduced to a CSA of 30-34°. The acromion index had no significant independent influence on the model (P = .427), whereas lateral acromion angle was an independently significant predictor of required ALA to achieve a CSA of 34° (P = .019). Sclerosis of the greater tuberosity was significantly associated with a CSA of 35° or greater (P = .003). CONCLUSIONS: The amount of ALA needed to reduce a large CSA to 34° correlates with the CSA before ALA and can preoperatively be planned with the use of a simple equation. LEVEL OF EVIDENCE: Level III; cross-sectional design; epidemiology study.

The forgotten fragment: additional lesser tuberosity fixation of 4-part proximal humeral fractures-a biomechanical investigation.

BACKGROUND: Fractures of the proximal humerus are common. The most frequent surgical treatment option is open reduction and locking plate fixation. Multifragmentary fractures, including 3- and 4-part fractures, are especially challenging to treat because they correlate with an increased risk of fixation failure. In the past, several mechanisms of additional fixation were investigated, but none directly addressed the lesser tuberosity (LT). The goal of this study was to investigate the biomechanical impact of additional anterior fracture fixation in lateral locked plating (LLP) of 4-part proximal humeral fractures (PHFs). METHODS: Twenty-seven fresh frozen human shoulder specimens (mean age, 80 years) with intact rotator cuffs (RCs) were randomized into 4 groups: 3-part PHF with LLP and RC cerclage (n = 6); 4-part PHF with LLP and RC cerclage as standard of care (n = 7); 4-part PHF with LLP, RC cerclage, and 2 anterior 3.5-mm cortical screws (n = 7); and 4-part PHF with LLP, RC cerclage, and additional anterior one-third tubular plate (additional anterior plating [AAP], n = 7). Static load of the RC was simulated with weights. A force-controlled cyclic loading test was performed with a servo-hydraulic testing machine, followed by load-to-failure testing. An optical motion capture system recorded humeral head range of motion. RESULTS: LLP of a 4-part PHF showed more humeral head motion than LLP of a 3-part PHF without fracture of the LT (P < .001). Fixing the LT to the humeral head with two 3.5-mm screws significantly reduced humeral head motion compared with LLP with RC cerclage alone (P < .006). Using AAP significantly increased the construct stiffness compared with the standard of care (P = .03). CONCLUSION: LLP of a 4-part PHF is biomechanically less stable than LLP of a 3-part PHF without fracture of the LT. Additional screw fixation of the LT in 4-part PHFs improves stability compared with LLP alone. In case of metaphyseal comminution, AAP is favorable from a biomechanical perspective.

In-hospital Complications Are More Likely to Occur After Reverse Shoulder Arthroplasty Than After Locked Plating for Proximal Humeral Fractures.

BACKGROUND: Currently, there seems to be a paradigm change in the surgical treatment of proximal humeral fractures in patients aged 65 years and older, with a considerable increase in the use of reverse total shoulder arthroplasty (RTSA) compared with angular stable internal fixation (locking plate fixation). However, even among shoulder specialists there is controversy regarding the best treatment strategy. QUESTIONS/PURPOSES: To evaluate for (1) a greater risk of in-hospital major adverse events, (2) a greater risk for in-hospital surgical complications, and (3) a greater risk of 30-day mortality, locking plate fixation and RTSA were compared for the treatment of proximal humerus fractures of patients aged 65 years and older after controlling for potentially confounding variables in a large-database analysis. METHODS: Health claims data of the largest German insurance company including approximately one-third of the population (26.5 million policyholders) between 2010 and 2018 were analyzed. This database was chosen because of its size, nationwide distribution, and high quality/completeness. In total, 55,070 patients (≥ 65 years of age) treated with locking plate fixation (75% [41,216]) or RTSA (25% [13,854]) for proximal humeral fracture were compared. As primary endpoints, major adverse events (including acute myocardial infarction, stroke, organ failure, resuscitation, and death) and surgical complications (infection, hematoma, loss of reduction, dislocation, and revision surgery) were analyzed. The risk of all endpoints was analyzed with multivariable logistic regression models in the context of comorbidities to address existing group differences. RESULTS: After controlling for potentially confounding variables such as age, sex, and risk profile, RTSA was associated with a higher risk for major adverse events (OR 1.40 [95% CI 1.29 to 1.53]; p < 0.001) and surgical complications (OR 1.13 [95% CI 1.05 to 1.21]; p < 0.01) compared with locking plate fixation. There was no evidence for an increase in mortality (OR 0.98 [95% CI 0.86 to 1.12]; p = 0.81). CONCLUSION: The increased in-hospital risk for major adverse events and surgical complications may moderate the enthusiasm associated with RTSA for proximal humeral fractures in patients 65 years and older. Treatment decisions should be based on individual risk estimation to avoid potential harmful events. Future studies must include long-term outcomes and quality of life to enlighten these findings in a broader context. LEVEL OF EVIDENCE: Level III, therapeutic study.

Glenoid concavity has a higher impact on shoulder stability than the size of a bony defect.

PURPOSE: Surgical treatment of shoulder instability caused by anterior glenoid bone loss is based on a critical threshold of the defect size. Recent studies indicate that the glenoid concavity is essential for glenohumeral stability. However, biomechanical proof of this principle is lacking. The aim of this study was to evaluate whether glenoid concavity allows a more precise assessment of glenohumeral stability than the defect size alone. METHODS: The stability ratio (SR) is a biomechanical estimate of glenohumeral stability. It is defined as the maximum dislocating force the joint can resist related to a medial compression force. This ratio was determined for 17 human cadaveric glenoids in a robotic test setup depending on osteochondral concavity and anterior defect size. Bony defects were created gradually, and a 3D measuring arm was used for morphometric measurements. The influence of defect size and concavity on the SR was examined using linear models. In addition, the morphometrical-based bony shoulder stability ratio (BSSR) was evaluated to prove its suitability for estimation of glenohumeral stability independent of defect size. RESULTS: Glenoid concavity is a significant predictor for the SR, while the defect size provides minor informative value. The linear model featured a high goodness of fit with a determination coefficient of R2 = 0.98, indicating that 98% of the SR is predictable by concavity and defect size. The low mean squared error (MSE) of 4.2% proved a precise estimation of the SR. Defect size as an exclusive predictor in the linear model reduced R2 to 0.9 and increased the MSE to 25.7%. Furthermore, the loss of SR with increasing defect size was shown to be significantly dependent on the initial concavity. The BSSR as a single predictor for glenohumeral stability led to highest precision with MSE = 3.4%. CONCLUSION: Glenoid concavity is a crucial factor for the SR. Independent of the defect size, the computable BSSR is a precise biomechanical estimate of the measured SR. The inclusion of glenoid concavity has the potential to influence clinical decision-making for an improved and personalised treatment of glenohumeral instability with anterior glenoid bone loss.

[Trends in the surgical treatment of fractures of the pelvic ring : A nationwide analysis of operations and procedures code (OPS) data between 2005 and 2017]. / Trends in der operativen Therapie von Frakturen des Beckenrings : Eine bundesweite Analyse von OPS-Daten zwischen 2005 und 2017.

AIM: The aim of this study was to analyze the epidemiological trends and incidences in inpatient pelvic surgery in the period from 2005 to 2007. METHOD: Approximately 194 million anonymized diagnosis-related groups (DRG) inpatient records were collected by the German Federal Statistical Office between 2005 and 2017. These data were screened for pelvic procedures, gender and age of the patients. Statistical testing was performed using the χ2-test and Mann-Whitney U-test (p < 0.05). RESULTS: Between 2005 and 2017 the number of closed reduction and internal fixation of the pelvic ring with screw fixation increased by +1116%. The use of screw fixation for closed reduction and internal fixation of the sacroiliac joint increased by +800%. The number of cases of open reduction and internal fixation of fractures of the pelvic ring and pelvic rim increased by +185% and reposition with external fixator increased by +188%. In 2005 more surgical procedures were undertaken in male inpatients, whereas more surgical procedures were undertaken in female inpatients in 2017. In general, a large increase in the number of pelvic procedures was observed in the group of patients >50 years old. CONCLUSION: There was an increase in the number of all analyzed pelvic procedures between 2005 and 2017. Especially the use of screw fixation increased. The introduction of new techniques (e.g. screw fixation of the sacroiliac joint) and progress and innovation in the field of three-dimensional navigation techniques, the demographic trend, greater mobility and higher demands on functionality of older patients might explain this increase in pelvic procedures.