Larger-diameter trunnions and bolt-reinforced taper junctions are associated with less tribocorrosion in reverse total shoulder arthroplasty.

BACKGROUND: Morse taper junction tribocorrosion is recognized as an important failure mode in total hip arthroplasty. Although taper junctions are used in almost all shoulder arthroplasty systems currently available in the United States, with large variation in design, limited literature has described comparable analyses of taper damage in these implants. In this study, taper junction damage in retrieved reverse total shoulder arthroplasty (RTSA) implants was assessed and analyzed. METHODS: Fifty-seven retrieved RTSAs with paired baseplate and glenosphere components with Morse taper junctions were identified via database query; 19 of these also included paired humeral stems and trays or spacers with taper junctions. Components were graded for standard damage modes and for fretting and corrosion with a modified Goldberg-Cusick classification system. Medical records and preoperative radiographs were reviewed. Comparative analyses were performed assessing the impact of various implant, radiographic, and patient factors on taper damage. RESULTS: Standard damage modes were commonly found at the evaluated trunnion junctions, with scratching and edge deformation damage on 76% and 46% of all components, respectively. Fretting and corrosion damage was also common, observed on 86% and 72% of baseplates, respectively, and 23% and 40% of glenospheres, respectively. Baseplates showed greater moderate to severe (grade ≥ 3) fretting (43%) and corrosion (27%) damage than matched glenospheres (fretting, 9%; corrosion, 13%). Humeral stems showed moderate to severe fretting and corrosion on 28% and 30% of implants, respectively; matched humeral trays or spacers showed both less fretting (14%) and less corrosion (17%). On subgroup analysis, large-tapered implants had significantly lower summed fretting and corrosion grades than small-tapered implants (P < .001 for both) on glenospheres; paired baseplate corrosion grades were also significantly lower (P = .031) on large-tapered implants. Factorial analysis showed that bolt reinforcement of the taper junction was also associated with less fretting and corrosion damage on both baseplates and glenospheres. Summed fretting and corrosion grades on glenospheres with trunnions (male) were significantly greater than on glenospheres with bores (female) (P < .001 for both). CONCLUSIONS: Damage to the taper junction is commonly found in retrieved RTSAs and can occur after only months of being implanted. In this study, tribocorrosion predominantly occurred on the taper surface of the baseplate (vs. glenosphere) and on the humeral stem (vs. tray or spacer), which may relate to the flexural rigidity difference between the titanium and cobalt-chrome components. Bolt reinforcement and the use of large-diameter trunnions led to less tribocorrosion of the taper junction. The findings of this study provide evidence for the improved design of RTSA prostheses to decrease tribocorrosion.

Stemless reverse total shoulder arthroplasty: a systematic review.

BACKGROUND: The use of reverse total shoulder arthroplasty and stemless anatomic total shoulder replacement has been increasing in the United States every year. Stemless humeral components in reverse total shoulder arthroplasty are only approved for clinical trials in the United States with an investigational device exception with limited data. METHODS: A systematic review on stemless reverse total shoulder arthroplasty was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A search was conducted on November 25, 2020, using the MEDLINE/PubMed, Cochrane, and Embase databases. All articles were reviewed by 2 independent evaluators, with any conflicts or issues resolved by consensus or a final decision by the senior author. The primary outcomes extracted were complications, radiographic results, and outcome scores. RESULTS: We evaluated 10 studies that used either the Total Evolutive Shoulder System (TESS) or Verso implant. There were 430 total patients and 437 total procedures; 266 patients in the TESS group underwent a total of 272 procedures, and 164 patients in the Verso group underwent a total of 165 procedures. The mean age at the time of surgery was 73.8 years (range, 38-93 years). The mean follow-up period ranged from 6.4 to 101.6 months per study. There was an overall trend of improved clinical outcome scores, a 0.2% humeral component loosening rate, and an 11.2% complication rate. CONCLUSIONS: This review shows that the clinical and functional outcomes following stemless or metaphyseal reverse total shoulder arthroplasty are quite promising, especially with the low rate of humeral-sided complications. There continues to be a need for additional long-term studies and randomized clinical trials.

Intravenous tranexamic acid reduces total blood loss in reverse total shoulder arthroplasty: a prospective, double-blinded, randomized, controlled trial.

BACKGROUND: Patients undergoing reverse total shoulder arthroplasty (RTSA) are at risk of significant perioperative blood loss. To date, few studies have examined the effectiveness of tranexamic acid (TXA) to reduce blood loss in the setting of RTSA. METHODS: In a prospective, double-blinded, single-surgeon trial, we analyzed 102 patients undergoing primary RTSA who were randomized to receive intravenous TXA (n = 53) or placebo (n = 49). Calculated total blood loss, drain output, and hemoglobin (Hb) drop were measured. Postoperative transfusions were recorded. Complications were assessed out to 6 weeks postoperatively. RESULTS: Total blood loss was less for the TXA group (1122.4 ± 411.6 mL) than the placebo group (1472.6 ± 475.4 mL, P < .001). Total drain output was less for the TXA group (221.4 ± 126.2 mL) than the placebo group (371.9 ± 166.3 mL , P < .001). Total Hb loss was less in the TXA group (154.57 ± 60.29 g) compared with the placebo group (200.1 ± 65.5 g, P = .001). Transfusion rates differed significantly at postoperative day 1; however, overall transfusion rates did not vary significantly. Seven patients (14.3%) and 12 units were transfused in the placebo group compared with 3 patients (5.7%) and 3 units in the TXA group. DISCUSSION: In this cohort of patients undergoing primary RTSA, TXA was effective in reducing total drain output, total Hb loss, and total blood loss compared with a placebo control.

Influence of Body Mass Index on Clinical Outcomes in Reverse Total Shoulder Arthroplasty.

The purpose of this study was to compare reverse total shoulder arthroplasty (RTSA) outcomes in normal weight, overweight, and obese patients. A RTSA outcomes registry was reviewed for rotator cuff-deficient patients with a minimum 2-year follow-up. Fractures, rheumatoid arthritis, and revisions were excluded. Based on World Health Organization body mass index (BMI) classification, there were 29 normal weight, 50 overweight, and 51 obese patients. All groups demonstrated significant improvements from preoperative to most recent follow-up in function scores, pain, and forward elevation. Obese and overweight groups had significantly worse preoperative rotation than the normal weight group. Postoperatively, there was no significant difference in absolute values or degree of improvement of rotation between groups. There was no significant difference in the incidence of radiographic or clinical complications between groups. Results of this study suggest that BMI has little influence on outcomes or risk of complication following RTSA. Longer-term studies are needed to determine if these results are maintained. (Journal of Surgical Orthopaedic Advances.

Preoperative deltoid size and fatty infiltration of the deltoid and rotator cuff correlate to outcomes after reverse total shoulder arthroplasty.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) allows the deltoid to substitute for the nonfunctioning rotator cuff. To date, it is unknown whether preoperative deltoid and rotator cuff parameters correlate with clinical outcomes. QUESTIONS/PURPOSES: We asked whether associations exist between 2-year postoperative results (ROM, strength, and outcomes scores) and preoperative (1) deltoid size; (2) fatty infiltration of the deltoid; and/or (3) fatty infiltration of the rotator cuff. METHODS: A prospective RTSA registry was reviewed for patients with cuff tear arthropathy or massive rotator cuff tears, minimum 2-year followup, and preoperative shoulder MRI. Final analysis included 30 patients (average age, 71±10 years; eight males, 22 females). Only a small proportion of patients who received an RTSA at our center met inclusion and minimum followup requirements (30 of 222; 14%); however, these patients were found to be similar at baseline to the overall group of patients who underwent surgery in terms of age, gender, and preoperative outcomes scores. The cross-sectional area of the anterior, middle, and posterior deltoid was measured on axial proton density-weighted MRI. Fatty infiltration of the deltoid, supraspinatus, infraspinatus, teres minor, and subscapularis were quantitatively assessed on sagittal T1-weighted MR images. Patients were followed for Constant-Murley score, American Shoulder and Elbow Surgeons (ASES) scores, subjective shoulder value, pain, ROM, and strength. Correlations of muscle parameters with all outcomes measures were calculated. RESULTS: Preoperative deltoid size correlated positively with postoperative Constant-Murley score (67.27±13.07) (ρ=0.432, p=0.017), ASES (82.64±14.25) (ρ=0.377; p=0.40), subjective shoulder value (82.67±17.89) (ρ=0.427; p=0.019), and strength (3.72 pounds±2.99 pounds) (ρ=0.454; p=0.015). Quantitative deltoid fatty infiltration (7.91%±4.32%) correlated with decreased postoperative ASES scores (ρ=-0.401; p=0.047). Quantitative fatty infiltration of the infraspinatus (30.47%±15.01%) correlated with decreased postoperative external rotation (34.13°±16.80°) (ρ=-0.494; p=0.037). CONCLUSIONS: Larger preoperative deltoid size correlates with improved validated outcomes scores, whereas fatty infiltration of the deltoid and infraspinatus may have deleterious effects on validated outcomes scores and ROM after RTSA. The current study is a preliminary exploration of this topic; future studies should include prospective enrollment and standardized MRI with a multivariate statistical approach. Quantitative information attained from preoperative imaging not only holds diagnostic value, but, should future studies confirm our findings, also might provide prognostic value. This information may prove beneficial in preoperative patient counseling and might aid preoperative and postoperative decision-making by identifying subpopulations of patients who may benefit by therapy aimed at improving muscle properties. LEVEL OF EVIDENCE: Level III, prognostic study.

Elucidating trends in revision reverse total shoulder arthroplasty procedures: a retrieval study evaluating clinical, radiographic, and functional outcomes data.

BACKGROUND: The purpose of this study was to explore relationships between damage modes in explanted reverse total shoulder arthroplasty (RTSA) components, patient and radiographic risk factors, and functional data to elucidate trends in RTSA failure. METHODS: Fifty RTSA systems, retrieved from 44 patients, with 50 polyethylene (PE) liners, 30 glenospheres, 21 glenoid baseplates, 13 modular humeral metaphases, and 17 humeral stems, were examined for damage modes, including abrasion, burnishing, dishing, embedding, scratching, and pitting. PE liners were also analyzed for delamination and edge deformation. Charts were reviewed for patient, surgical, and functional data. Pre-revision radiographs were analyzed for scapular notching and loosening. RESULTS: Average term of implantation was 20 months (range, 0-81 months). Metallic components exhibited abrasion, burnishing, dishing, pitting, and scratching. PE liners displayed all damage modes. Damage was exhibited on 93% of glenospheres and 100% of PE liners. Of 29 aseptic shoulders, 13 showed evidence of scapular notching and 5 of humeral loosening. There was a moderate correlation between radiographically observed implant failure or dissociation and PE embedding (r = 0.496; P < .001). There were weak and moderate correlations between scapular notching severity and PE dishing (r = 0.496; P = .006), embedding (r = 0.468; P = .010), and delamination (r = 0.384; P = .040). CONCLUSIONS: To date, this is the largest series of retrieved RTSA components and the first to relate damage modes to radiographic and clinical data. Most damage was observed on the PE liners, on both the articular surface and rim, and glenosphere components. Correlation of retrieval findings with radiographic and clinical data may help establish predictors of prostheses at risk for failure.

The evaluation of the failed shoulder arthroplasty.

As the incidence of shoulder arthroplasty continues to rise, the orthopedic shoulder surgeon will be increasingly faced with the difficult problem of evaluating a failed shoulder arthroplasty. The patient is usually dissatisfied with the outcome of the previous arthroplasty as a result of pain, but may complain of poor function due to limited range of motion or instability. A thorough and systematic approach is necessary so that the most appropriate treatment pathway can be initiated. A comprehensive history and physical examination are the first steps in the evaluation. Diagnostic studies are numerous and include laboratory values, plain radiography, computed tomography, ultrasound imaging, joint aspiration, nuclear scans, and electromyography. Common causes of early pain after shoulder arthroplasty include technical issues related to the surgery, such as malposition or improper sizing of the prosthesis, periprosthetic infection, neurologic injury, and complex regional pain syndrome. Pain presenting after a symptom-free interval may be related to chronic periprosthetic infection, component wear and loosening, glenoid erosion, rotator cuff degeneration, and fracture. Poor range of motion may result from inadequate postoperative rehabilitation, implant-related factors, and heterotopic ossification. Instability is generally caused by rotator cuff deficiency and implant-related factors. Unfortunately, determining the cause of a failed shoulder arthroplasty can be difficult, and in many situations, the source of pain and disability is multifactorial.

Clinical and radiographic results of cementless reverse total shoulder arthroplasty: a comparative study with 2 to 5 years of follow-up.

BACKGROUND: Most studies of reverse total shoulder arthroplasty (RTSA) involve cemented humeral stems. To our knowledge, this is the first study to compare the results of cementless RTSA, using a porous-coated stem designed for uncemented fixation, with cemented RTSA. METHODS: A prospective database of patients undergoing RTSA was retrospectively reviewed for patients with a diagnosis of cuff tear arthropathy or severe rotator cuff deficiency with minimum 2-year follow-up. Of these, 37 patients had cemented RTSA and 64 patients had cementless RTSA. Outcome measures included Constant-Murley scores, American Shoulder and Elbow Surgeons scores, visual analog pain scale scores, range of motion, patient satisfaction, and radiographic evidence of complication. RESULTS: Compared with preoperative values, both cohorts demonstrated significant improvements (P < .01) in all functional scores, active forward elevation, and active internal rotation. There was no significant difference (P > .05) in comparing the changes in these values after surgery between the cemented and cementless cohorts. On radiographic evaluation, there was no evidence of loosening or humeral components "at risk" of loosening in either group. There was no significant difference (P = 1.0) in the incidence of humeral component radiolucent lines between the cemented and uncemented cohorts. There was no significant difference (P = .30) in the incidence of scapular notching between the cemented (n = 8) and uncemented (n = 10) cohorts. CONCLUSION: Cementless fixation of a porous-coated RTSA humeral stem provides clinical and radiographic outcomes equivalent to those of cemented stems at minimum 2-year follow-up. With advantages such as simplified operative technique, no cement-related complications, greater ease of revision, and long-lasting biologic fixation, uncemented fixation may provide several benefits over cemented fixation.

Complication rates and efficacy of single-injection vs. continuous interscalene nerve block: a prospective evaluation following arthroscopic primary rotator cuff repair without a concomitant open procedure.

Background: To compare the complications and efficacy of pain relief of the interscalene anesthetic block using either a single-injection (SI) vs. a continuous, indwelling catheter (CIC) for arthroscopic rotator cuff repair surgery. Methods: Patients undergoing primary, arthroscopic rotator cuff repair without concomitant open procedure or biceps tenodesis were prospectively enrolled by 4 fellowship-trained sports medicine and shoulder surgeons. Patients received either a SI or CIC preoperatively based on surgeon preference. Patients were contacted by phone to complete a standard questionnaire on postoperative days (PODs) 1, 3, 7, 14, and 28. Patients were asked to rate the efficacy of their subjective pain relief (scale of 0-10), document issues with the catheter, describe analgesic usage, and report pharmacological and medical complications. The primary outcome was measured as complication rate. Postoperative narcotic use, patient satisfaction, and visual analog scale pain scores were measured as secondary outcomes. Results: Seventy patients were enrolled, 33 CIC patients (13 male, 20 female, mean age 61 ± 8 years) and 37 SI patients (20 male, 17 female, mean age 59 ± 10 years). There were significantly more injection/insertion site complications in the CIC group (48%) vs. the SI group (11%, P = .001). The incidence of motor weakness was higher in the CIC group on POD 1 (P = .034), but not at any subsequent time points. On POD 1, CIC patients had a clinically significantly lower pain score compared to SI (3.2 vs. 5.4; P = .020). Similar scores were observed at subsequent time points until POD 28, when CIC again had a lower pain score (0.8 vs. 2.7; P = .005). However, this did not reach clinical significance. All patients in both groups rated a satisfaction of 9 or 10 (scale 0-10) with the anesthesia provided by their nerve block. Conclusion: CIC interscalene nerve blocks had an increased risk for injection site complications and minor complications in the immediate postoperative period when using the CIC for arthroscopic rotator cuff repair without any concomitant open procedures. CIC blocks demonstrated clinically significant superior pain relief on POD 1 but were equal to SI blocks at every time point thereafter. Superior pain relief of CIC at POD 28 was not clinically significant. CIC catheters do not appear to markedly decrease the use of postoperative narcotics. Despite this trend in complication rates and pain scores, all patients in both groups were satisfied with their nerve block.

Does using the medial or lateral humeral line improve reliability of Baumann angle measurement on plain x-ray? The effect of humeral length visualized on the x-ray.

BACKGROUND: Baumann angle (BA) is a common measure of coronal plane alignment of the distal humerus. We hypothesize that the reliability of measuring BA would be improved by using the medial and lateral cortical margins of the humerus seen on plain x-ray, rather than the estimated central humeral line, which is the "standard" technique. Further, we analyze whether the amount of humerus visible on the film improves the reliability of the method. METHODS: A total of 71 anteroposterior elbow digital radiographs from patients aged 0 to 12 were measured 3 times by 5 qualified observers. Each digital measurement included (1) BA using the estimated central humeral line; (2) BA using the medial humeral line (BA-MHL); and (3) BA using the lateral humeral line (BA-LHL). Inadequate radiographs or those showing any indication of current or previous fracture were excluded. Intraobserver reliability was estimated for each rater using a 1-way analysis of variance model and interobserver reliability of each set of measurements was estimated using a 2-way analysis of variance. RESULTS: The mean and SD for the BA, BA-MHL, and BA-LHL in females were 70.0 (6.73), 68.0 (6.84), and 72.3 (7.93), respectively, and for males 73.0 (5.22), 70.0 (5.56), and 76.0 (6.18), respectively. Intraobserver reliability (intraclass correlation coefficient) for BA, BA-MHL, and BA-LHL averaged 0.85, 0.92, and 0.90, respectively. Average interobserver reliability (intraclass correlation coefficient) for BA, BA-MHL, and BA-LHL were 0.79, 0.71, and 0.76, respectively. Intraobserver and interobserver reliability of BA and BA-LHL were significantly improved when at least 7 cm of humerus was visible on the x-ray, as compared with <7 cm visible. CONCLUSIONS: Intrarater reliability is better for both BA-LHL and BA-MHL than for standard BA (using the estimated central humeral axis). Interrater reliability was best using standard BA. Reliability of all methods is improved when >7 cm of the distal humerus is visible on the radiograph. In addition, at least 7 cm of the distal humerus on anteroposterior radiographs improves reliability of measuring BA. LEVEL OF EVIDENCE: Diagnostic study-Level II.

Treatment of plastic deformation of the forearm in young adults with double-level osteotomies: case reports.

Plastic deformation of the forearm is a rare injury in young adults that occurs when a slow bending or rotational force is applied to the arm, most commonly in the setting of an industrial workplace accident. There are currently no guidelines for treatment of the residual forearm deformity that often results in limitations of forearm supination and pronation. We present 2 cases demonstrating that deformity correction with single cortex, double-level osteotomies combined with rigid plate fixation and early range of motion exercise that results in good functional outcomes.

The lateral capitellohumeral angle in normal children: mean, variation, and reliability in comparison to Baumann's angle.

BACKGROUND: Angular deformity is the most common complication of supracondylar humerus fracture. Baumann's angle (BA) is an established radiographic measure of coronal plane deformity after this injury. Numerous radiographic methods have been used to assess sagittal plane deformity, however, the mean, variability, and reliability of these measures has not been established. The purpose of this study was to determine the mean, SD, and intraobserver/interobserver reliability of the lateral capitellohumeral angle (LCHA) in children without evidence of fracture and compare them with those of BA. METHODS: Seventy-one sets of anteroposterior and lateral elbow radiographs were selected and stratified into 6-year age categories with equal number of males and females in each category. Five physicians performed 3 separate measurements of LCHA and BA on each film set. Statistical calculations were performed to determine mean, SD, measurement reliability, and differences between patients groups. RESULTS: The mean LCHA ±1 SD and BA ± 1 SD measurements were 50.8 ± 6 degrees and 71.5 ± 6.2 degrees, respectively, and did not vary significantly by age, side, or sex (P>0.05). The LCHA showed good intraobserver (correlation coefficient 0.67) and fair interobserver (0.37) reliability, whereas BA showed excellent intraobserver (0.86) and interobserver (0.80) reliability. The expected SD for repeated measurement of a radiograph by a single observer was 2.6 degrees for BA and 5.2 degrees for LCHA. CONCLUSIONS: The LCHA is a simple measurement to perform using digital tools. In normal elbows, the mean angle is 51 ± 6 degrees and does not vary by age, side, or sex. LCHA variability in normal elbow radiographs is similar to BA. Its reliability is inferior to BA, but improves with age. Sagittal angulation abnormality of at least 12 degrees (<39 or >63 degrees) is necessary to be confident that the change is not because of measurement error alone. Further research is needed to better define the relationship of sagittal plane angular deformity to clinical outcome. LEVEL OF EVIDENCE: Diagnostic study with poor reference standard, Level IV.

Radiographic evaluation of humeral head reconstruction with stemmed and stemless spherical implants compared with stemless elliptical head implants.

BACKGROUND: The purpose of this study was to compare the accuracy of anatomic reconstruction of three different humeral head designs after anatomic total shoulder arthroplasty. METHODS: Postoperative radiographs of 117 patients who underwent anatomic total shoulder arthroplasty with three different implant designs (stemmed spherical, stemless spherical, and stemless elliptical) were analyzed for landmarks that represented the prearthritic state and final implant position. We assessed the change in center of rotati7on and humeral head height on the anteroposterior view and the percentage of prosthesis overhang on the axillary lateral view. A modified anatomic reconstruction index, a compound score that rated each of the 3 parameters from 0 to 2, was created to determine the overall accuracy of the reconstruction. RESULTS: Excellent modified anatomic reconstruction index scores (5 or 6 points) were achieved by 68.1% of the cases in the stemless elliptical group compared with 33.3% of the cases in the stemless spherical group and by 28.3% of the cases in the stemmed spherical group (P = .001).The mean difference in restoration of humeral head height (P < .001) and percentage of prosthesis overhang (P < .001) was superior for the stemless elliptical group compared with the two other spherical head groups. There was no difference between groups for the shift in center of rotation (P = .060). CONCLUSIONS: In this radiographic investigation comparing three different humeral head designs with respect to anatomic restoration parameters, the stemless elliptical implant more closely restored the geometry of the prearthritic humeral head as assessed by humeral head height, prosthesis overhang, and a compound reconstruction score.

Baseplate Options for Reverse Total Shoulder Arthroplasty.

PURPOSE OF REVIEW: Baseplate fixation has been known to be the weak link in reverse total shoulder arthroplasty (RTSA). A wide variety of different baseplates options are currently available. This review investigates the recent literature to present the reader with an overview of the currently available baseplate options and modes of fixation. RECENT FINDINGS: The main elements that differentiate baseplates are the central fixation element, the size of the baseplate, the shape, the backside geometry, whether or not an offset central fixation exists, the number of peripheral screws, and the availability of peripheral augmentation. The wide array of baseplate options indicates that no particular design has proven superiority. As such, surgeons should be aware of their options and choose an implant that the surgeon is comfortable with and one that best suits the individual patient anatomy. With the growing number of RTSA procedures and registries with long-term follow-up, future investigations will hopefully delineate the ideal baseplate design to optimize survivorship.

Venous Thromboembolism After Shoulder Arthoplasty and Arthroscopy.

Venous thromboembolism (VTE) in the orthopaedic literature largely focuses on lower extremity trauma and arthroplasty, with relatively few investigations of VTE after shoulder surgery. Because the rate of shoulder surgery, especially arthroplasty, continues to expand, it is important for practicing surgeons to understand the magnitude of risk, potential consequences, and prevention methods with regard to VTE. VTE after shoulder surgery has been a topic of increasing interest over the past decade, and the purpose of this review is to examine the recent literature on pathophysiology, risk factors, incidence, diagnosis, sequelae, prevention, treatment, and current recommendations regarding VTE after shoulder surgery.

Outcomes Following Low-Profile Mesh Plate Osteosynthesis of Patella Fractures.

Treatment of patella fractures is fraught with complications and historically poor functional outcomes. A fixation method that allows for early mobilization and decreases symptomatic hardware rates will improve knee range of motion, postoperative functional status, and reoperation rates. The purpose of this study was to evaluate the functional outcomes after locked plate osteosynthesis of patella fractures at a Level 1 trauma center. A retrospective case series was conducted of patients who underwent open reduction internal fixation (ORIF) of a patella fracture using a locked mesh plating technique coupled with neutralization of forces on the distal pole of the patella. Twelve patients were evaluated at a mean follow-up of 19 months (range, 6-30) with physical exam, functional outcomes, and radiographs. There were 9 women and 3 men with an average age of 66.1 years (range, 53-75). Radiographic bony union was achieved in all patients by 3-month follow-up. Visual Analog Pain Score averaged 1.7 (median, 1.0; range, 0-8), the mean Knee Outcome Score - Activities of Daily Living Scale was 83.9 (median, 92.1; range, 45.7-100.0), the mean Short Form Musculoskeletal Function Assessment (SMFA) Function Index was 9.9 (median, 3.7; range, 0.7-41.2), and the mean SMFA Bother Index was 11.1 (median, 3.1; range, 0-62.5). The SF-36 Physical Component Score mean was 48.4 ± 8.5 and the SF-36 Mental Component Score mean was 54.1 ± 9.6. No complications developed and there were no reoperations for nonunion, infection, or symptomatic hardware. This study demonstrates that locked plate osteosynthesis for operative patella fractures can reliably achieve bony union with potentially superior functional outcomes as compared with traditional methods. Further studies are needed to evaluate plate fixation for patella fractures, but early results are promising.

Novel Anterior Plating Technique for Patella Fracture Fixation.

Patella fracture fixation remains a significant challenge for orthopedic surgeons. Although tension band fixation allows for reliable osseous union, especially in simple fracture patterns, it still presents several problems. Plate fixation of patella fractures is a method that allows for more rigid stabilization and earlier mobilization. At the authors' level 1 trauma center, one fellowship-trained trauma surgeon has transitioned to using a novel anterior, low-profile mesh plate construct for all types of patella fractures. This construct allows for stable fixation, osseous union, and neutralization of the inferior pole for even the most comminuted of patella fractures. [Orthopedics. 2017; 40(4):e739-e743.].

Biomechanical Evaluation of All-Polyethylene Pegged Bony Ingrowth Glenoid Fixation Techniques on Implant Micromotion.

Newer glenoid components that allow for hybrid cement fixation via traditional cementation of peripheral pegs and bony ingrowth into an interference-fit central peg introduce the possibility of long-term biological fixation. However, little biomechanical work has been done on the initial stability of these components and the various fixation options. We conducted a study in which all-polyethylene glenoid components with a centrally fluted peg were implanted in polyurethane blocks with interference-fit, hybrid cement, and fully cemented fixation (5 per fixation group). Biomechanical evaluation of glenoid loosening, according to ASTM Standard F-2028-12, subjected the glenoids to 50,000 cycles of rim loading, and glenoid component motion was recorded with 2 differential variable reluctance transducers fixed to each glenoid prosthesis. Fully cemented fixation exhibited significantly less mean distraction in comparison with interference-fit fixation (P < .001) and hybrid cement fixation (P < .001). Hybrid cement fixation exhibited significantly less distraction (P < .001), more compression (P < .001), and no significant difference in glenoid translation (P = .793) in comparison with interference-fit fixation. Fully cemented fixation exhibited the most resistance to glenoid motion in comparison with hybrid cement fixation and interference-fit fixation. However, hybrid cement fixation and interference-fit fixation exhibited equivocal motion. Given these results, cementation of peripheral pegs may confer no additional initial stability over that provided by uncemented interference-fit fixation.

Use of a Topical Thrombin-Based Hemostatic Agent in Shoulder Arthroplasty.

Shoulder arthroplasty is associated with significant blood loss, often requiring blood transfusion. Hemostatic agents are used in various surgical specialties to minimize blood loss, but to date few studies have examined their efficacy in shoulder arthroplasty. We retrospectively reviewed 211 consecutive shoulder arthroplasty cases performed by a single surgeon. Our hypothesis was that patients treated with a topical thrombin prepared with a hemostatic matrix (Surgiflo) would have decreased perioperative blood loss. Patients with humeral fractures or preexisting blood disease were excluded. Control patients were managed December 2012 through April 2013. Study patients were managed May 2013 through August 2013 using the same surgical technique with the additional application of the hemostatic agent before closure. Charts were reviewed for demographics, estimated blood loss, drain output, transfusion rates, and complications. Hidden blood loss was calculated using a validated method. There were no differences in estimated blood loss (P = .301), drain output (P = .906), or hidden blood loss (P = .601) between groups. There was no increased incidence of transfusion between study (25%) and control (20%) groups (P = .407). No increased complications resulted from use of the hemostatic agent (P = .764). On the basis of these results, we cannot conclude that this topical hemostatic agent is effective as a blood loss management tool in shoulder arthroplasty.