Understanding the Interaction of Thermal, Rheological, and Mechanical Parameters Critical for the Processability of Polyvinyl Alcohol-Based Systems during Hot Melt Extrusion.

Hot melt extrusion (HME) is a common manufacturing process used in the pharmaceutical industry to improve the solubility of poorly soluble active pharmaceutical ingredients (API). The goal is to create an amorphous solid dispersion (ASD) where the amorphous form of the API is stabilized within a polymer matrix. Traditionally, the development of pharmaceutically approved polymers has focused on requirements such as thermal properties, solubility, drug-polymer interactions, and biocompatibility. The mechanical properties of the material have often been neglected in the design of new polymers. However, new downstream methods require more flexible polymers or suitable plasticizer polymer combinations. In this study, two grades of the polymer polyvinyl alcohol (PVA), which is already established for HME, are investigated in terms of their mechanical, rheological, and thermal properties. The mechanical properties of the extruded filaments were tested by the three-point bending test. The rheological behavior was analyzed by oscillating plate measurements. Thermal analysis was performed by differential scanning calorimetry (DSC). In addition, the solid and liquid plasticizers mannitol, sorbitol, triacetin, triethyl citrate, polyethylene glycol, and glycerol were evaluated for use with PVA and their impact on the polymer properties was elaborated. Finally, the effects of the plasticizers are compared to each other, and the correlations are analyzed statistically using principal component analysis (PCA). Thereby, a clear ranking of the plasticizer effects was established, and a deeper understanding of the polymer-plasticizer interactions was created.

Is malunion of the greater tuberosity after reverse shoulder arthroplasty in patients with complex proximal humerus fracture associated with worse clinical outcomes? A prospective cohort study.

PURPOSE: To assess patient outcomes following reverse shoulder arthroplasty in patients with complex proximal humerus fracture and the clinical implications of greater tuberosity malunions. METHODS: This prospective study included 56 patients who underwent RSA (DELTA XTEND™, DePuy Synthes, Warsaw, IN, USA) to treat proximal humerus fractures. We used a standardized suture technique to reattach the tuberosities. Demographic, comorbidity, and radiological parameters were collected. Assessments at 2-year follow-up (n = 49) are given as follows: range of motion (ROM), pain level, Constant Murley scores (CS), subjective shoulder value (SSV), and tuberosity healing. RESULTS: Anatomic tuberosity healing was achieved in 31 (55%) patients (group 1), 14 (25%) had a malunion (group 2), and complete migration occurred in 11 (20%) (group 3). No statistically significant differences between groups 1 and 2 were detected: CS (p = 0.53), SSV (p = 0.07), ROM (forward flexion (FF) p = 0.19, internal rotation (IR) p = 0.34, and external rotation (ER) p = 0.76). Group 3 had poorer outcomes (median [IQR]) than group 1: CS (59 [50-71]) vs. 72 [65-78]), FF (120 [100-150]) vs. 150 [125-160] and ER (- 20 [- 20 to 10] vs. 30 [20-45], respectively. Three complications (group 1) occurred: one-stage revision after low-grade infection, haematoma due to early rivaroxaban intake, and open reduction and internal fixation for acromion insufficiency fracture. No patients showed signs of stem or glenoid loosening after 2 years. CONCLUSION: Cases with complete superior migration experienced poorer clinical outcomes than those with anatomic healing. Despite a relatively high malunion rate, the outcomes were not significantly worse in these patients compared to anatomically healed GT cases.

Spinal cord injury and prescribed opioids for pain: a scoping review.

OBJECTIVE: Spinal cord injury (SCI) is a life-altering neurological condition affecting physical and psycho-social functioning and associated high rates of pain. Thus, individuals with SCI may be more likely to be exposed to prescription opioids. A scoping review was conducted to synthesize published research findings on post-acute SCI and prescription opioid use for pain, identify literature gaps, and propose recommendations for future research. METHODS: We searched 6 electronic bibliographic databases (PubMed [MEDLINE], Ovid [MEDLINE], EMBASE, Cochrane Library, CINAHL, PsychNET) for articles published from 2014 through 2021. Terms for "spinal cord injury" and "prescription opioid use" were used. Included articles were in English and peer reviewed. Data were extracted using an electronic database by 2 independent reviewers. Opioid use risk factors for chronic SCI were identified and a gap analysis was performed. RESULTS: Of the 16 articles included in the scoping review, a majority were conducted in the United States (n = 9). Most articles lacked information on income (87.5%), ethnicity (87.5%), and race (75%). Prescription opioid use ranged from 35% to 64% in articles reporting this information (n = 7 articles, n = 3675 participants). Identified risk factors for opioid use included middle age, lower income, osteoarthritis diagnosis, prior opioid use, and lower-level spinal injury. Limited reporting of diversity in study populations, absence of risk of polypharmacy, and limited high quality methodology were identified gaps. CONCLUSIONS: Future research should report data on prescription opioid use in SCI populations, with additional demographics such as race, ethnicity, and income, given their importance to risk outcomes.

Complications following arthroscopic-assisted coracoclavicular stabilization in patients with unstable lateral clavicle fractures.

PURPOSE: Lateral clavicle fractures are unstable and prone to nonunions, which is why they are often treated surgically rather than conservatively. Despite the variety of surgical techniques found in the literature, the best method for treating this rare fracture type has not yet been determined. Our case series aimed to describe a coracoclavicular (CC) reconstruction technique and to assess complications and patient outcomes 1 year postoperatively. METHODS: Nineteen patients who underwent surgery for an unstable lateral clavicle fracture (IIB, IIC, IID) with a suture button device (Dog Bone, Arthrex, Inc., Naples, FL, USA) were available for clinical and radiological follow-up. The assessments included the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment (ASES) score, the Constant Score (CS), the Subjective Shoulder Value (SSV), as well as the ipsilateral and contralateral coracoclavicular distance. RESULTS: The median age was 50 years (IQR 28-59), 13 (68.4%) were male and the delay to surgery was 5 days (IQR 2-9). The median clinical scores were 100 (ASES), 91 (CS), and 95 (SSV). The CC distance improved postoperatively (p = 0.003). However, nonunion occurred in 3 (15.8%) patients, 5 (26.3%) had other complications, and 5 (26.3%) needed revision surgery (4 plate removals and 1 pseudoarthrosis). The overall complication rate was 36.8%. CONCLUSION: Restoring the CC ligaments alone could not reliably achieve fracture stability, with more than one-third of cases in this series experiencing major complications. Given the high revision and nonunion rates, we do not recommend this type of surgical technique.

Increased injury severity and hospitalization rates following crashes with e-bikes versus conventional bicycles: an observational cohort study from a regional level II trauma center in Switzerland.

BACKGROUND: As electric bicycles (e-bikes) become increasingly popular, reports of injuries associated with e-bike usage are also rising. Patterns, characteristics, and severity of injuries following e-bike crashes need further investigation, particularly in contrast to injuries from conventional bicycle crashes. METHODS: This prospective observational study included 82 patients treated at a Level II trauma center for injuries resulting from an electric or conventional bicycle crash. Data were collected over one year (05.09.2017-19.09.2018) during in- and outpatient visits. A study-specific case report form was used to identify the bicycle type, cycling behavior (e.g., use of a helmet, safety gear, alcohol), and circumstances of the crash (e.g., road conditions, speed, cause of the incident, time of day, season). Additional information about patient demographics, treatment, and injury characteristics, such as the Injury Severity Score (ISS) and body region injured, were documented. Results were analyzed using chi-square, Fisher's exact, or Wilcoxon tests. Simple logistic or linear regression models were used to estimate associations. RESULTS: Of the 82 patients, 56 (67%) were riding a conventional bike and 27 (33%) were using an e-bike. Most incidents were either single-bicycle crashes (66%) or automobile collisions (26%), with no notable difference in prevalence rates between groups. Although a higher proportion of conventional bikers were male (67% vs. 48%), the difference was not significant. E-bikers were older (median 60 years (IQR 44-70) vs. 45 years (IQR 32-62); p = 0.008), were hospitalized more often (48% vs. 24%, p = 0.025), and had worse ISS (median 3 (IQR 2-4) vs. 1 (IQR 1-3), p < 0.001), respectively. Body regions most affected were the extremities (78%) and external/skin (46%), and these were distributed similarly in both groups. Concomitant injury patterns of the thorax/chest with external/skin were higher among e-bikers (p < 0.001). When we controlled for the difference in the median age of the two groups, only the injury severity score of e-bikers remained significantly worse. CONCLUSIONS: Hospitalization and chest trauma rates were higher among e-bikers. After controlling for the older age of this group, the severity of their injuries remained worse than in conventional cyclists. Initial clinical assessments at trauma units should include an evaluation of the thorax/chest, particularly among elderly e-bikers. LEVEL OF EVIDENCE: Level III.

A retrospective comparison of clinical and radiological outcomes using palmar or dorsal plating to treat complex intraarticular distal radius fractures (AO 2R3 C3).

INTRODUCTION: Complex intraarticular distal radius fractures are common, and treatment with open reduction and internal fixation (ORIF) can be done through either the palmar or dorsal approach. There is scant evidence, however, indicating which approach is more suitable. We compared clinical and radiological outcomes of patients with AO 2R3 C3 fractures surgically treated with one of these approaches. MATERIALS AND METHODS: From January 2015 to November 2018, 72 surgically treated patients with AO 2R3 C3 fractures were radiologically (12 months) and clinically (mean 26 months) evaluated. Forty-one patients underwent ORIF using the palmar approach (Group 1), and the dorsal approach was used in 31 patients (Group 2). Radiological parameters were measured using the AO scoring system immediately following surgery and 12 months later. Clinical assessments included the range of motion, PRWE and DASH scores. RESULTS: At the immediate postoperative assessment, the median AO score was 5.5 (IQR 2-9.5, range 0-30.5) for Group 1 and 8 (IQR 5-15, range 0-27) for Group 2, and 12-month follow-up results were 4.5 (IQR 1.5-10, range 0-41) and 6.5 (IQR 5-11, range 0-29.5), respectively. Group 1 had more favorable results for the flexion, extension, radial abduction, PRWE and DASH parameters. The plate removal and reoperation rates were higher in Group 2. DISCUSSION: When treating complex intraarticular distal radius fractures, we found the palmar approach was more advantageous for this fracture pattern. Nevertheless, a dorsal approach may still be suitable for intraarticular comminuted distal radius fractures with dorsally displaced joint fragments.

Determination of feed forces to improve process understanding of Fused Deposition Modeling 3D printing and to ensure mass conformity of printed solid oral dosage forms.

Fused Deposition Modeling is a suitable technique for the production of personalized solid oral dosage forms. For widespread application, it is necessary to be able to print a wide range of different formulations to address individual therapeutic needs. Due to the complexity of formulation composition (e.g., due to different compounds, excipients for enhancement of release and mechanical properties) and limited mechanical understanding, determination of suitable printing parameters is challenging. To address this challenge, we have developed a feed force tester using a Texture Analyser setup that mimics the actual printing process. Feed force data were compared to the mass of tablets printed from technical materials as well as pharmaceutical filaments containing ketoconazole at high drug loads of 20% and 40% and polyvinyl alcohol. By determining a feed force limit for the 3D printer from feed force data of several formulations printed, it was possible to specify the operable printing range, where printing is reproducible and printed mass corresponds the target mass. Based on these results, rational optimization of the printing process in terms of speed, time and temperature for different materials and formulations is possible.

Perioperative blood transfusions in hip and knee arthroplasty: a retrospective assessment of combined risk factors.

INTRODUCTION: Accurate identification of patients at risk of blood transfusion can reduce complications and improve institutional resource allocation. Probabilistic models are used to detect risk factors and formulate patient blood management strategies. Whether these predictors vary among institutions is unclear. We aimed to identify risk factors among our patients who underwent total hip (THA) or knee (TKA) arthroplasty, and combine these predictors to improve our model. MATERIALS AND METHODS: We retrospectively assessed risk factors among 531 adults who underwent elective THA or TKA from January 2016 to November 2018. Using relevant surgical and patient characteristics gathered from electronic medical records, we conducted univariable and multivariable analyses. For our logistic regression model, we measured the impact of independent variables (age, gender, operation type (THA or TKA) and preoperative hemoglobin concentration) on the need for a transfusion. RESULTS: Of the 531 patients, 321 had THA (uncemented) and 210 had TKA. For the selected period, our transfusion rate of 8.1% (10.6% THA and 4.3% TKA) was low. Univariable analyses showed that lower BMI (p < 0.001) was associated with receiving a transfusion. Important factors identified through logistic regression analyses were age (estimated effect of an interquartile range increase in age: OR 3.89 [CI 95% 1.96-7.69]), TKA (OR - 0.77 [CI 95% - 1.57-0.02]), and preoperative hemoglobin levels (estimated effect of interquartile range increase in hemoglobin: OR 0.47 [CI 95% 0.31-0.71]). Contrary to findings from previous reports, gender was not associated with transfusion. CONCLUSIONS: Previously published predictors such as advanced age, low preoperative hemoglobin, and procedure type (THA) were also identified in our analysis. However, gender was not a predictor, and BMI showed the potential to influence risk. We conclude that, when feasible, the determination of site-specific transfusion rates and combined risk factors can assist practitioners to customize care according to the needs of their patient population. LEVEL OF EVIDENCE: Level 3, retrospective cohort study.

Using mini-arthrotomy for dorsal plating to treat intraarticular distal radius fractures: can it improve radiological and clinical outcomes?

PURPOSE: Using palmar plating to treat complex intraarticular distal radius fractures is standard of care. However, fracture fragments can also be managed using a dorsal approach with arthrotomy, which is useful when treating fractures involving the dorsal joint aspect. We compared radiological and clinical outcomes after dorsal plating with or without an intraoperative arthrotomy. METHODS: 31 of the 359 patients with a distal radius fracture had an AO Type 2R3 C3 fracture surgically treated using a dorsal approach (01/2015-10/2018). Fractures other than C3 were excluded from this analysis. Group 1 (n = 14) had no arthrotomy, Group 2 (n = 17) underwent intraoperative dorsal mini-arthrotomy. Clinical results were measured by range of motion (ROM), Patient-rated wrist evaluation (PRWE) and Disabilities of arm, shoulder and hand (DASH) scores. Radiological results were evaluated using the AO scoring system. RESULTS: ROM, DASH and PRWE did not differ significantly between groups. Joint surface restoration was insufficient in five patients in Group 1 (p = 0.05). A trend towards better radiological results, although not statistically significant, was noted in Group 2 (p = 0.06). Plate removal was performed in 12 patients due to limited ROM (6 patients in each group). One patient (Group 2) with chronic pain and step off in the joint line underwent corrective osteotomy. CONCLUSIONS: We did not detect a difference in patient outcomes using the dorsal longitudinal mini-arthrotomy; however, it may prevent incongruent joint reconstruction since all cases occurred in Group 1. In the absence of intraoperative CT scan, longitudinal mini-arthrotomy may be used to enhance visualization and achieve joint surface reconstruction.

Non-invasive continuous blood pressure monitoring (ClearSight™ system) during shoulder surgery in the beach chair position: a prospective self-controlled study.

BACKGROUND: The beach chair position that is commonly used in shoulder surgery is associated with relative hypovolemia, which leads to a reduction in arterial blood pressure. The effects of patient positioning on the accuracy of non-invasive continuous blood pressure monitoring with the ClearSight™ system (CS-BP; Edwards Lifesciences, Irvine CA, USA) have not been studied extensively. Our research aim was to assess agreement levels between CS-BP measurements with traditional blood pressure monitoring techniques. METHODS: For this prospective self-controlled study, we included 20 consecutively treated adult patients undergoing elective shoulder surgery in the beach chair position. We performed Bland-Altman analyses to determine agreement levels between blood pressure values from CS-BP and standard non-invasive (NIBP) methods. Perioperative measurements were done in both the supine (as reference) and beach chair surgical positions. Additionally, we compared invasive blood pressure (IBP) measurements with both the non-invasive methods (CS-BP and NIBP) in a sub-group of patients (n = 10) who required arterial blood pressure monitoring. RESULTS: We analyzed 229 data points (116 supine, 113 beach chair) from the entire cohort; per patient measurements were based on surgical length (range 3-9 supine, 2-10 beach chair). The mean difference (±SD; 95% limits of agreement) in the mean arterial pressure (MAP) between CS-BP and NIBP was - 0.9 (±11.0; - 24.0-22.2) in the beach chair position and - 4.9 mmHg (±11.8; - 28.0-18.2) when supine. In the sub-group, the difference between CS-BP and IBP in the beach chair position was - 1.6 mmHg (±16.0; - 32.9-29.7) and - 2.8 mmHg (±15.3; - 32.8-27.1) in the supine position. Between NIBP and IBP, we detected a difference of 3.0 mmHg (±9.1; - 20.8-14.7) in the beach chair position, and 4.6 mmHg (±13.3; - 21.4-30.6) in the supine position. CONCLUSIONS: We found clinically acceptable mean differences in MAP measurements between the ClearSight™ and non-invasive oscillometric blood pressure systems when patients were in either the supine or beach chair position. For all comparisons of the monitoring systems and surgical positions, the standard deviations and limits of agreement were wide. TRIAL REGISTRATION: This study was prospectively registered at the German Clinical Trial Register (www.DRKS.de; DRKS00013773 ). Registered 26/01/2018.

Tuberosity union in patients with proximal humerus fractures treated with reverse shoulder arthroplasty: a technical note and exploratory analysis.

PURPOSE: The use of reverse shoulder arthroplasty (RSA) to treat complex humerus fractures is increasing, especially in older, osteoporotic patients. Refixation and tuberosity healing are needed to achieve an optimal range of motion (ROM), external rotation, active forward elevation, and patient satisfaction. Proper healing has been reported, however, in only 40-84% of cases. Our study's aim was to describe a simple, reproducible fixation technique designed to improve tuberosity healing. METHODS: We included 30 patients with acute proximal humerus fractures undergoing RSA (Global Unite Reverse Fracture, DePuy Synthes, Warsaw, IN, USA) with tuberosity reattachment. The humerus stem was cemented in 24 cases. A standardized suture technique with two fiber tapes was used to reattach tuberosities. Clinical and radiological parameters, which were collected one year post-operatively, included ROM, pain level, Constant scores, subjective shoulder value (SSV), and tuberosity healing. RESULTS: The mean age of the patients was 79.3 years (± 7; range 65-92), and the tuberosity healing rate was 90.0% (27 of 30). Two patients showed migration (one nonunion, one malunion), and another had complete resorption after an initial period of proper healing. Radiolucent lines around the humerus stem occurred in one case, and three patients had scapular notching. The mean SSV was 86% (± 11; range 60-100), the Constant score was 72 (± 10.3; range 48-92), the active forward flexion was 140° (± 14.3; range 115-165), and external rotation was 23° (± 16.5; range 0-50). CONCLUSIONS: This reattachment technique, which is simple and reproducible, achieved a higher tuberosity healing rate than previously published rates.

Is the Additional Effort for an Intraoperative CT Scan Justified for Distal Radius Fracture Fixations? A Comparative Clinical Feasibility Study.

INTRODUCTION: It is currently unclear whether the additional effort to perform an intraoperative computed tomography (CT) scan is justified for articular distal radius fractures (DRFs). The purpose of this study was to assess radiological, functional, and clinical outcomes after surgical treatment of distal radius fractures when using conventional fluoroscopy vs. intraoperative CT scans. METHODS: Inclusion criteria: Surgical treatment of DRF between 1 January 2011 and 31 December 2011, age 18 and above. Group distribution: intraoperative conventional fluoroscopy (Group Conv) or intraoperative CT scans (Group CT). EXCLUSION CRITERIA: Use of different image intensifier devices or incomplete data. DRF classification according to the Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification. Outcome variables included requirement of revision surgeries, duration of surgery, absorbed radiation dose, and requirement of additional CT scans during hospitalization. RESULTS: A total of 187 patients were included (Group Conv n = 96 (51.3%), Group CT n = 91 (48.7%)). AO Classification: Type A fractures n = 40 (50%) in Group Conv vs. n = 16 (17.6%) in Group CT, p < 0.001; Type B: 10 (10.4%) vs. 11 (12.1%), not significant (n.s.); Type C: 38 (39.6%) vs. 64 (70.3%), p < 0.001. In Group Conv, four (4.2%) patients required revision surgeries within 6 months, but in Group CT no revision surgery was required. The CT scan led to an intraoperative screw exchange/reposition in 23 (25.3%) cases. The duration of the initial surgery (81.7 ± 46.4 min vs. 90.1 ± 43.6 min, n.s.) was comparable. The radiation dose was significantly higher in Group CT (6.9 ± 1.3 vs. 2.8 ± 7.8 mGy, p < 0.001). In Group Conv, 11 (11.5%) patients required additional CT scans during hospitalization. CONCLUSION: The usage of intraoperative CT was associated with improved reduction and more adequate positioning of screws postoperatively with comparable durations of surgery. Despite increased efforts by utilizing the intraoperative CT scan, the decrease in reoperations may justify its use.

Polyaxial locking plate fixation in periprosthetic, peri-implant and distal shaft fractures of the femur : a comparison of open and less invasive surgical approaches.

Polyaxial locking plate fixation is a widely performed treatment for femoral shaft, periprosthetic, and peri-implant fractures in elderly patients. This study's purpose was to compare patient outcomes following the open technique (OT) and less invasive techniques (LIT). Data were gathered from 44 patients with 46 fractures treated with polyaxial locking plate between 2010-2015. Twenty fractures underwent the OT and 26 had a LIT. Long-term assessments for 83% of the fractures were done at a median of 23 months postoperatively. Bone healing rates were 82% in the OT and 100% in the LIT group (p=0.0688). The difference in the median duration of the surgery (OT 120 minutes, LIT 73 minutes) (p< 0.001) was the main statistically significant finding. Both surgical techniques resulted in similarly favourable outcomes. The LIT would be the preferred operating technique, especially when treating patients more susceptible to intra- and/or postoperative morbidity.

A retrospective analysis of surgical outcomes following direct anterior hip arthroplasty with or without a surgical extension table.

PURPOSE: Using a surgical extension table during total hip arthroplasty (THA) is widely considered state-of-the-art. However, intra-operative leg positioning requires additional time and leg length determination can be challenging. Our study's aim was to compare patient outcomes, particularly leg length precision, following surgery with or without an extension table. METHODS: This retrospective study included data from medical records of 324 patients who underwent THA using the direct anterior approach by one surgeon at a Swiss cantonal hospital (2015-2017). Patients were grouped by table type-standard (TS) or extension table (TE). Variables analyzed were demographics, operative/anaesthetic conditions, and medical outcomes. The leg length was measured pre- and post-operatively with mediCAD Classic®. RESULTS: An extension table was used in 161 (49.7%) patients. The median operative duration (minutes) was shorter in TS (55 (interquartile range (IQR) 48-67) than TE (60 (IQR 54-69)) (p = 0.002) and blood loss (ml) was lower (TS = 400 (IQR 300-500), TE = 500 (IQR 300-600), p = 0.0175). The median post-operative leg length discrepancy (mm) was less in TS (TS = 1 (IQR 0-3), TE = 2 (IQR 0-4), p = 0.0122). All four dislocations occurred in TE, and 7.4% of patients had complications (TS = 7%, TE = 7.5%, p = 0.99). CONCLUSION: We found that operating on a standard table during THA resulted in slightly more favourable outcomes. Given the added expenses, human resources, and time associated with an extension table, opting for a standard table remains a sensible choice.

Placement of TOF-Cuff® on the lower leg for neuromuscular and blood pressure monitoring during anesthetic induction for shoulder surgeries.

PURPOSE: The aim of this study was to compare two devices for neuromuscular monitoring during anesthetic induction. TOF-Cuff® was installed on the lower leg stimulating the tibial nerve, while the more conventional TOF-Scan® was installed over the ulnar nerve at the wrist. Methods Twenty adult patients were enrolled in this prospective, controlled study. Train-of-four (TOF) was recorded every 15 s until TOF ratio of 0%. Mean arterial blood pressure (MAP) was assessed with TOF-Cuff® and with standard anesthesia monitoring from the brachial artery. MAP was measured before and after anesthetic induction. Time to TOF ratio = 0% was compared with one-sample t test and Bland-Altman plots. Results Patients received 0.53 ± 0.09 mg atracurium per kg body weight intravenously. Mean time to TOF ratio = 0% was 150.8 s (± 43.7) for TOF-Scan®, and 174.4 s (± 42.7) for TOF-Cuff® (p = 0.1356). Bias was - 15.9 (95% confidence interval - 37.5 to 5.6) with 95% limits of agreement of - 95.2 to 63.3. Twenty-five percent of the patients had a technical issue with a TOF-Cuff® measurement. For MAP, mean difference was 1.4 (95% confidence interval - 2.4 to 5.2) with 95% limits of agreement of - 22.7 to 25.5. Conclusion The time from administration of a common dose of atracurium to a TOF ratio of 0% assessed with TOF-Cuff® stimulating the tibial nerve compared to TOF-Scan® stimulating the ulnar nerve showed large limits of agreement in Bland-Altman analysis. There was a high failure rate with TOF-Cuff® measurements on the lower leg.

Application of a new polyester patch in arthroscopic massive rotator cuff repair-a prospective cohort study.

BACKGROUND: Massive rotator cuff (RC) tears still present a clinically challenging problem, with reported rerupture rates in up to 94%. The study objective was to determine the impact of synthetic patch augmentation for massive RC tears. METHODS: Between June 2012 and 2014, we performed 50 arthroscopic RC reconstructions augmented with a synthetic polyester patch. Pre- and postoperative imaging methods included arthrographic magnetic resonance imaging, arthrographic computed tomography, and ultrasound examination to determine tendon integrity or rerupture. Clinical outcome was evaluated using the Constant-Murley score and the subjective shoulder value. Mean clinical midterm and final follow-up was 22 months (9-35 months) and 52 months (25-74 months), respectively. RESULTS: The mean Constant-Murley score increased significantly from 36.5 (±16.4 standard deviation [SD]) preoperatively to a midterm value of 81.2 (±9.6 SD; P < .0001) and further improved to a mean of 83.4 (±10.8 SD) at final follow-up. The mean subjective shoulder value increased from 40.3 (±24.3 SD) to 89.2 (±12.9 SD; P < .0001) at midterm and to 89.6 (±15.2 SD) at final follow-up. We observed 7 complete reruptures (14%). However, reruptures did not correlate with revision surgery, which was performed in 8 patients. The main reason for revision was frozen shoulder or arthrofibrosis with an intact reconstruction and patch, which was performed in 6 cases. CONCLUSIONS: The retear rate of 14% compared favorably with nonaugmented RC repairs in the literature. Therefore, we conclude that patch augmentation in massive RC tears is feasible to reduce retears and to improve clinical outcome.

The arthroscopic triple-row modified suture bridge technique for rotator cuff repair: functional outcome and repair integrity.

BACKGROUND: The optimal technique for arthroscopic rotator cuff repair is still controversial. Large tears with a high grade of retraction have an especially high risk of retearing. This study reports the clinical and radiologic results of a triple-row modified suture bridge technique for the treatment of full-thickness rotator cuff tears with medium and high grades of retraction. METHODS: A total of 101 shoulders in 100 patients underwent a triple-row modified suture bridge reconstruction for full-thickness rotator cuff tears with retraction grade II and grade III according to Patte; 81 patients were reached for follow-up 36.2 months after surgery. At follow-up, clinical outcome was assessed by the American Shoulder and Elbow Surgeons score, subjective shoulder value, visual analog scale score, University of California-Los Angeles shoulder score, and Constant score (CS). At follow-up, an ultrasound examination was performed to determine tendon integrity or retears in all patients. RESULTS: The overall retear rate was 4.9% (4/81). The clinical outcome was good to excellent (American Shoulder and Elbow Surgeons score, 94 ± 11; subjective shoulder value, 92 ± 12; University of California-Los Angeles shoulder score, 33 ± 5; Constant score, 90 ± 9). In the radiologic follow-up, no retear was found in any of the follow-up patients after an average of 36.2 months. There was no significant difference in clinical outcome parameters between rotator cuff tears Patte II and Patte III (P > .05). CONCLUSION: For tears with a high grade of retraction, surgical treatment using a triple-row modified suture bridge technique represents a good treatment option with a low rate of retearing and good to excellent clinical results.

Reconstrucción anatómica del Acromion en casos de fracturas traumáticas y posterior a artroplastia reversa del Hombro. Reporte de Casos / Anatomic reconstruction of the acromion in cases of traumatic fractures after reverse shoulder arthroplasty. Report of a series of cases

Introducción Tanto las fracturas traumáticas del acromion, así como las fracturas acromiales por insuficiencia posterior a artroplastia reversa del hombro, son entidades poco frecuentes. Con la ampliación des los criterios operativos para la artroplastia reversa del hombro, es de suponer un aumento en el caso des las fracturas acromiales por insuficiencia posteriores a dicho procedimiento quirúrgico. Al ser estas entidades poco frecuentes hacen falta en la literatura recomendaciones basadas en la evidencia para el manejo de estas, las cuales representan un reto para el especialista tratante. Materiales y Métodos Reporte de seis casos entre 2013 y 2016 en el hospital cantonal de Frauenfeld (Suiza) de dos grupos de pacientes con fracturas del Acromion. En el grupo A se clasificaron tres pacientes que presentaron fractura por insuficiencia del acromion posterior a artroplastia reversa del Hombro. En el grupo B clasificaron tres pacientes con fracturas traumáticas del acromion en las cuales el manejo conservador no fue exitoso. Los dos grupos de pacientes fueron sometidos al mismo método quirúrgico con reducción abierta y reconstrucción anatómica del Acromion por medio de fijación con placa y tornillos interfragmentarios. Resultados Posterior a la intervención quirúrgica, la función del hombro se recuperó en todos los pacientes del Grupo A. La flexión anterior aumentó en promedio de 53° a 127°, y la abducción mejoró de 52° a 125°. Las mediciones posteriores al año de la intervención mostraron puntajes constantes entre 55-71, así como un valor subjetivo de hombro (SSV) de 50-90. En el Grupo B, el rango de movimiento preoperatorio se mantuvo constante. La flexión hacia delante mejoró de 133° a 157° y la abducción aumentó de 147° a 153°. Un año después de la cirugía, los puntajes de Constant en el grupo B variaron de 70 a 86 y el SSV se encontró entre 80 a 100. Los tres pacientes del Grupo B consiguieron retomar sus actividades diarias sin dolor y pudieron regresar al trabajo. La extracción de la placa fue necesaria en la mitad de los pacientes de la cohorte (Grupo A n=1, Grupo B n=2). Discusión La fractura del acromion es una condición seria que puede causar daño significativo al funcionamiento del hombro. Tanto en pacientes con ARH así como en pacientes sin ARH previa, nuestra técnica operativa abierta de reconstrucción anatómica del acromion mostró buenos resultados. Recomendamos el manejo quirúrgico por medio de reconstrucción con placa y clavos de fijación. Nivel de evidencia: IV

Aim To propose a surgical technique to treat the traumatic acromion fractures, as well as acromion fractures before reverse total Shoulder Replacement (TSR). Methods Six patients were treated with the same fixation technique between December 2013 and December 2016. Three patients had acromial insufficiency fractures (type II) following TSR (Group A). The other three patients, who had traumatic acromion fractures, underwent unsuccessful conservative treatment (Group B). Surgical treatment involved reconstruction of the acromion using an open technique with plate and interfragmentary screw fixation. Results Following reconstruction, shoulder function was regained in all patients in Group A. Forward flexion increased, on average, from 53° to 127°, and abduction improved from 52° to 125°. Measurements at one-year follow-up were Constant scores from 55-71, and subjective shoulder value (SSV) from 50-90. In Group B, preoperative range of motion was not substantially diminished. Forward flexion improved from 133° to 157°, and abduction increased from 147° to 153°. One year following surgery, the Constant scores in Group B ranged from 70-86, and SSV was 80-100. All three patients performed daily activities without pain, and were able to return to work. Plate removal was necessary in half the patients in the cohort (Group A n=1; Group B n=2). Conclusion An acromion fracture is a serious condition that can cause significant damage to shoulder functioning. In patients with or without previous TSR, this fixation technique was used successfully to reconstruct the anatomic lateral and basal acromion. Evidence Level: IV

The traumatic acromion fracture: review of the literature, clinical examples and proposal of a treatment algorithm.

PURPOSE: Traumatic acromion fractures are rare and typically occur in patients with multiple fractures, which often delays diagnosis. Limited guidance exists on the treatment of these fractures. We present a review of the literature from the last 20 years and describe our experience in treating five patients-two conservatively and three with open reduction and internal fixations (ORIF). METHODS: We used the U.S. National Library of Science database, MEDLINE®, to search for all pertinent publications from January 1999 to December 2017. Included were retrospective or prospective studies, including case series and case reports, describing treatment for traumatic acromion fractures and clinical and/or radiological outcomes. For our case reports, we present five patients with traumatic acromion fractures who were treated at our institution between 2013 and 2017. RESULTS: Through our review of 14 publications, we found that current recommendations are often based on a limited number of cases. No gold standard to treat these fractures exists. Most authors recommend anatomic reconstruction, especially for dislocated fractures, persistent symptomatic non-unions or additional injuries to the superior shoulder suspensory complex. There is no clear trend in terms of the operative technique. With regard to our five clinical examples that were all initially treated conservatively, two were successful and three eventually required reconstruction with ORIF. Based on the findings of this review, we proposed a treatment algorithm for traumatic acromion fractures. CONCLUSIONS: A classification system providing clear guidance on treatment options is needed. Although the non-union rate with conservative treatment is relatively high, it is not always painful or limiting to shoulder function, especially in elderly or less active patients. Fixation seems to be a more suitable treatment option for active patients who are more likely to require revision of symptomatic non-unions.

Decision-making for complex scapula and ipsilateral clavicle fractures: a review.

INTRODUCTION: Complex scapula with ipsilateral clavicle fracures remains a challange and treatment recommendations are still missing.  This review provides an overview of the evolution of the definition, classification and treatment strategies for complex scapula and ipsilateral clavicle fractures. As with other rare conditions, consensus has not been reached on the most suitable management strategies to treat these patients. The aim of this review is twofold: to compile and summarize the currently available literature on this topic, and to recommend treatment approaches. MATERIALS AND METHODS: Included in the review are the following topics: biomechanics of scapula and ipsilateral clavicle fractures, preoperative radiological evaluation, surgical treatment of the clavicle only, surgical treatment of both the clavicle and scapula, and nonsurgical treatment options. RESULTS: A decision-making algorithm is proposed for different treatment strategies based on pre-operative parameters, and an example of a case treated our institution is presented to illustrate use of the algorithm. DISCUSSION: The role of instability in complex scapula with ipsilateral clavicle fractures remains unclear. The question of stability is preoperatively less relevant than the question of whether the dislocated fragments lead to compromised shoulder function.