Lack of Surgeon Standardization on Implant Selection in Ankle Fracture Fixation May Increase Costs and Decrease Contribution Margin

Background Surgical standardization has been shown to decrease costs without impacting quality; however, there is limited literature on this subject regarding ankle fracture fixation. Methods. Between October 5, 2015 and September 27, 2017, a total of 168 patients with isolated ankle fractures who underwent open reduction, internal fixation (ORIF) were analyzed. Financial data were analyzed across ankle fracture classification type, implant characteristics, and surgeons. Bivariate analyses were conducted. One-way analysis of variance was used to compare hardware costs across all 5 surgeons. Linear regression analysis was used to determine if hardware cost differed by surgeon when accounting for fracture type. Results The mean contribution margin was $4853 (SD $6446). There was a significant difference in implant costs by surgeon (range, lowest-cost surgeon: $471 [SD $283] to $1609 [SD $819]; P < .001). There was no difference in the use of a suture button or locking plate by fracture type (P = .13); however, the cost of the implant was significantly higher if a suture button or locking plate was used ($1014 [SD $666] vs $338 [SD $176]; P < .001). There was an association between surgeon 3 (β = 200.32 [95% CI 6.18-394.47]; P = .043) and surgeon 4 (β = 1131.07 [95% CI 906.84-1355.30]; P < .001) and higher hardware costs. Conclusions Even for the same ankle fracture type, a wide variation in implant costs exists. The lack of standardization among surgeons accounted for a nearly 3.5-fold difference, on average, between the lowest- and highest-cost surgeons, negatively affecting contribution margin. Levels of Evidence Level IV

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Biomechanical stability of complex coronal plane fracture fixation of the capitellum

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-021-04126-1 ◽

2021 ◽

Author(s):

Paul Borbas ◽

Rafael Loucas ◽

Marios Loucas ◽

Maximilian Vetter ◽

Simon Hofstede ◽

...

Keyword(s):

Fracture Fixation ◽

Ultimate Load ◽

Locking Plate ◽

Distal Humerus ◽

Coronal Plane ◽

Fixation Strength ◽

Biomechanical Stability ◽

Significant Difference ◽

Load To Failure ◽

Headless Compression Screws

Abstract Introduction Coronal plane fractures of the distal humerus are relatively rare and can be challenging to treat due to their complexity and intra-articular nature. There is no gold standard for surgical management of these complex fractures. The purpose of this study was to compare the biomechanical stability and strength of two different internal fixation techniques for complex coronal plane fractures of the capitellum with posterior comminution. Materials and methods Fourteen fresh frozen, age- and gender-matched cadaveric elbows were 3D-navigated osteotomized simulating a Dubberley type IIB fracture. Specimens were randomized into one of two treatment groups and stabilized with an anterior antiglide plate with additional anteroposterior cannulated headless compression screws (group antiGP + HCS) or a posterolateral distal humerus locking plate with lateral extension (group PLP). Cyclic testing was performed with 75 N over 2000 cycles and ultimately until construct failure. Data were analyzed for displacement, construct stiffness, and ultimate load to failure. Results There was no significant difference in displacement during 2000 cycles (p = 0.291), stiffness (310 vs. 347 N/mm; p = 0.612) or ultimate load to failure (649 ± 351 vs. 887 ± 187 N; p = 0.140) between the two groups. Conclusions Posterolateral distal humerus locking plate achieves equal biomechanical fixation strength as an anterior antiglide plate with additional anteroposterior cannulated headless compression screws for fracture fixation of complex coronal plane fractures of the capitellum. These results support the use of a posterolateral distal humerus locking plate considering the clinical advantages of less invasive surgery and extraarticular metalware. Level of evidence Biomechanical study.

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Associations Between the Fracture Type and Functional Outcomes After Distal Radial Fractures Treated With a Volar Locking Plate

Medicina ◽

10.3390/medicina49090062 ◽

2013 ◽

Vol 49 (9) ◽

pp. 62

Author(s):

Kęstutis Braziulis ◽

Rytis Rimdeika ◽

Rima Kregždytė ◽

Šarūnas Tarasevičius

Keyword(s):

Locking Plate ◽

Hand Function ◽

Linear Regression Analysis ◽

Type A ◽

Dash Score ◽

Volar Locking Plate ◽

Fracture Type ◽

Type C ◽

And Gender

Objective. The aim of this study to investigate the associations of fracture type, age, and gender with hand function after distal radius fractures treated with a volar locking plate at a 6-month follow-up. Material and Methods. A total of 120 patients with displaced distal radius fractures were included into the study. They were operated on using a volar locking plate system. All the fractures were classified according to the AO classification, and the patients were divided into 3 groups by the fracture type. The range of motion and grip strength were evaluated at the 6-month follow-up. Multivariate linear regression analysis was used to evaluate the associations of age, gender, and fracture type with the score of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. The DASH questionnaire was completed as an outcome measure. Results. A total of 28 patients experienced type A fractures; 70 patients, type B fractures; and 22 patients, type C fractures. No statistically significant difference regarding age and sex among the groups was observed. At 6 months after the surgery, the mean DASH score for type A, B, and C fractures was 16, 13, and 32, respectively (P=0.01). After the surgery, the radiographic parameters such as the volar tilt and the ulnar variance were significantly worse in the patients with type C fractures. Grip strength and the range of motion of the contralateral healthy hand at the 6-month follow-up were significantly better than those of the operated hand. The linear regression analysis showed that the type C fracture was the only factor significantly associated with lower DASH score. Conclusions. The patients with type C fractures treated with a volar locking plate had a worse wrist function as compared with the patients type A and B fractures at the 6-month follow-up. The postoperative hand function was significantly associated only with the type C fracture, while age and gender had no significant impact.

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Short-Term Results of a Ruptured Deltoid Ligament Repair During an Acute Ankle Fracture Fixation

Foot & Ankle International ◽

10.1177/1071100717732383 ◽

2017 ◽

Vol 39 (1) ◽

pp. 35-45 ◽

Cited By ~ 21

Author(s):

Seung Hun Woo ◽

Su-Young Bae ◽

Hyung-Jin Chung

Keyword(s):

Clinical Outcomes ◽

Fracture Fixation ◽

Ankle Fracture ◽

Linear Regression Analysis ◽

Case Series ◽

Deltoid Ligament ◽

Radiographic Findings ◽

Group 2 ◽

Repair Group

Background: There is no consensus on the optimal treatment or preferred method of operation for the management of acute deltoid ligament injuries during an ankle fracture fixation. This study aimed to analyze the outcomes of repairing the deltoid ligament during the fixation of an ankle fracture compared to conservative management. Methods: We retrospectively evaluated 78 consecutive cases of a ruptured deltoid ligament with an associated ankle fracture between 2001 and 2016. All of the ankle fractures were treated with a plate and screw fixation. Patients in the conservative treatment for ruptured deltoid ligament underwent management from 2001 to 2008 (37 fractures, group 1), while the operative treatment for ruptured deltoid ligament was included from 2009 to 2016 (41 fractures, group 2). The outcome measures included radiographic findings, the American Orthopaedic Foot & Ankle Society ankle-hindfoot scores, visual analog scale scores, and the Foot Function Index. All patients were followed for an average of 17 months. Results: Radiologic findings in both groups were comparable, but the final follow-up of the medial clear space (MCS) was significantly smaller in the group 2 ( P < .01). Clinical outcomes were similar between the two groups ( P > .05). Comparing those who underwent syndesmotic fixation between both groups, group 2 showed a significantly smaller final follow-up MCS, and all clinical outcomes were better in group 2 ( P < .05). Linear regression analysis showed that the final follow-up MCS had a significant influence on clinical outcomes ( P < .05). Conclusion: Although the clinical outcomes were not significantly different between the 2 groups, we obtained a more favorable final follow-up MCS in the deltoid repair group. Particularly when accompanied by a syndesmotic injury, the final follow-up MCS and the clinical outcomes were better in the deltoid repair group. In the case of high-grade unstable fractures of the ankle with syndesmotic instability, a direct repair of the deltoid ligament was adequate for restoring medial stability. Level of Evidence: Level III, retrospective comparative case series.

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Functional and Radiographic Outcomes Following Repair of Osteochondral Lesions After Ankle Fracture with Arthrex BioCartilage and Bone Marrow Aspirate Concentrate compared to Microfracture

Foot & Ankle Orthopaedics ◽

10.1177/2473011420s00456 ◽

2020 ◽

Vol 5 (4) ◽

pp. 2473011420S0045

Author(s):

Drew N. Stal ◽

Stephanie K. Eble ◽

Oliver B. Hansen ◽

Bopha Chrea ◽

Mark C. Drakos

Keyword(s):

Bone Marrow ◽

Outcome Measures ◽

Fracture Fixation ◽

Ankle Fracture ◽

Bone Marrow Aspirate ◽

Osteochondral Lesions ◽

Bone Marrow Aspirate Concentrate ◽

Significant Difference ◽

Patient Reported

Category: Arthroscopy; Basic Sciences/Biologics; Trauma Introduction/Purpose: There has been an increasing role for arthroscopy in ankle fracture fixation, particularly in assessing osteochondral lesions (OCL). Initial cartilage damage has been found to be an independent risk factor for post-traumatic ankle arthritis. Rates of osteochondral injury with ankle fracture remain varied, but have been reported up to 62-80%. Treatment for osteochondral injuries classically included debridement alone or debridement with microfracture. Recently, new biologic augments have come to market, including BioCartilage (Arthrex): a mixture of cadaveric articular cartilage extracellular matrix. This has been used in conjunction with bone marrow aspirate concentrate (BMAC). To date, no study has evaluated the outcomes of utilizing BioCartilage in the treatment of osteochondral lesions, or in comparison to microfracture alone, in conjunction with ankle fracture fixation. Methods: We conducted a retrospective analysis of all adult patients (age > 18) undergoing operative ankle fracture or syndesmotic fixation with concomitant ankle arthroscopy utilizing our Foot and Ankle Registry. Institutional Review Board (IRB) approval was obtained prior to data collection. Patient demographic data, laterality, fracture pattern and OCL size were documented. Those with full-thickness lesions requiring treatment were divided into groups based on the use of Biocartilage + BMAC or microfracture alone. Exclusion criteria included pediatric patients, distal tibia intra-articular, and open fractures. Outcome scores for pre- and postoperative patient reported outcome measures (PROMIS) were recorded, with a minimum 6- month follow up. Magnetic resonance observation of cartilage repair tissue (MOCART) scoring was performed for those with postoperative MRIs to evaluate OCL healing. We also included a group that had ankle fracture fixation and arthroscopy but without any osteochondral lesion to serve as a control. Results: 28 patients were treated with Biocartilage/BMAC; 19 with preoperative and 17 with postoperative PROMIS. 41 patients had microfracture; 20 with preoperative and 18 with postoperative PROMIS. 75 patients were identified in the non-OCL group; 60 with preoperative and 45 with postoperative PROMIS. Average follow-up was 20.61 months. There were no significant differences in postoperative PROMIS scores between the two treatment groups in all sub-categories. When comparing each treatment group to the control, there was a statistically significant increase in pre to postoperative global physical health scores for the non-OCL group compared to Biocartilage/BMAC. Postoperative MRIs were obtained in 12/28 patients with Biocartilage/BMAC and 10 /41 with microfracture. There was no significant difference between either group in overall MOCART scores or individual scoring categories. Conclusion: The role for arthroscopy in ankle fracture fixation is evolving, as is the treatment of identifiable osteochondral lesions. We sought to compare a novel biologic technique of Biocartilage and BMAC with microfracture for OCL management. Our results demonstrated no significant difference between treatments for postoperative PROMIS and MOCART scores. Outcome measures did not differ significantly when compared to our control group. Unfortunately, complete PROMIS and MOCART data was lacking in each group, limiting the ability to draw definitive conclusions. However, we believe this is a positive first step in understanding the role in treating osteochondral lesions associated with ankle fractures.

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Arthroscopic Findings During Routine Ankle ORIF: What is Being Missed?

Foot & Ankle Orthopaedics ◽

10.1177/2473011420s00262 ◽

2020 ◽

Vol 5 (4) ◽

pp. 2473011420S0026

Author(s):

Shain Howard ◽

Victor C. Hoang ◽

Troy S. Watson ◽

Candice L. Brady ◽

Adam Eudy

Keyword(s):

Fracture Fixation ◽

Ankle Fracture ◽

External Rotation ◽

Ankle Arthroscopy ◽

Ankle Fractures ◽

Osteochondral Lesions ◽

Fracture Type ◽

Syndesmotic Injury ◽

Patient Reported ◽

Articular Pathology

Category: Ankle; Arthroscopy; Trauma Introduction/Purpose: Ankle fractures are among the most common operatively treated injuries by orthopedic surgeons. However, up to 20% of patients will have continued pain and poor patient reported outcomes despite good/excellent radiographic results. Ankle fractures typically occur with varying degrees of intra-articular and soft tissue injury which can include ligamentous injury, loose bodies, and chondral lesions. The aim of study is to document intra-articular findings with ankle arthroscopy prior to ankle open reduction internal fixation (ORIF) and to contribute to the growing body of literature that shows this to be a safe adjunct to fracture fixation. Methods: IRB approval was obtained prior to chart review. This is a retrospective review of ankle fractures that were treated with arthroscopy and ORIF by a single surgeon. Between August 2016 and July 2018 Operative reports, office notes, and images were reviewed to identify intra-articular pathology and fracture type. Analysis was performed with regard to fracture type, presence and location of osteochondral lesions, presence of loose-body, syndesmotic injury, and deltoid injury. Results: Fifty-seven ankle fractures were identified that met inclusion criteria. 84.2% of the fractures had intra-articular pathology, most commonly a syndesmotic injury followed by loose joint body and osteochondral defect. Conclusion: Arthroscopic evaluation during ankle fracture ORIF, particularly pronation external rotation and supination external rotation patterns give a more detailed examination of associated pathology. Arthroscopy at the time of ankle fracture fixation is a safe adjunct and should be considered a potential compliment to routine ORIF of ankle fractures.

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Effect of Surgical Setting on Hospital-Reported Outcomes for Elective Lumbar Spinal Procedures: Tertiary Versus Community Hospitals

Global Spine Journal ◽

10.1177/2192568219848666 ◽

2019 ◽

Vol 10 (4) ◽

pp. 375-383 ◽

Cited By ~ 1

Author(s):

Tristan B. Weir ◽

Neil Sardesai ◽

Julio J. Jauregui ◽

Ehsan Jazini ◽

Michael J. Sokolow ◽

...

Keyword(s):

Pay For Performance ◽

Linear Regression Analysis ◽

Degenerative Spondylolisthesis ◽

Hospital Costs ◽

Patient Characteristics ◽

Tertiary Hospital ◽

Community Hospitals ◽

Single Level ◽

Significant Difference ◽

Reported Data

Study Design: Retrospective cohort study. Objective: As hospital compensation becomes increasingly dependent on pay-for-performance and bundled payment compensation models, hospitals seek to reduce costs and increase quality. To our knowledge, no reported data compare these measures between hospital settings for elective lumbar procedures. The study compares hospital-reported outcomes and costs for elective lumbar procedures performed at a tertiary hospital (TH) versus community hospitals (CH) within a single health care system. Methods: Retrospective review of a physician-maintained, prospectively collected database consisting of 1 TH and 4 CH for 3 common lumbar surgeries from 2015 to 2016. Patients undergoing primary elective microdiscectomy for disc herniation, laminectomy for spinal stenosis, and laminectomy with fusion for degenerative spondylolisthesis were included. Patients were excluded for traumatic, infectious, or malignant pathology. Comparing hospital settings, outcomes included length of stay (LOS), rates of 30-day readmissions, potentially preventable complications (PPC), and discharge to rehabilitation facility, and hospital costs. Results: A total of 892 patients (n = 217 microdiscectomies, n = 302 laminectomies, and n = 373 laminectomy fusions) were included. The TH served a younger patient population with fewer comorbid conditions and a higher proportion of African Americans. The TH performed more decompressions ( P < .001) per level fused; the CH performed more interbody fusions ( P = .007). Cost of performing microdiscectomy ( P < .001) and laminectomy ( P = .014) was significantly higher at the TH, but there was no significant difference for laminectomy with fusion. In a multivariable stepwise linear regression analysis, the TH was significantly more expensive for single-level microdiscectomy ( P < .001) and laminectomy with single-level fusion ( P < .001), but trended toward significance for laminectomy without fusion ( P = .052). No difference existed for PPC or readmissions rate. Patients undergoing laminectomy without fusion were discharged to a facility more often at the TH ( P = .019). Conclusions: We provide hospital-reported outcomes between a TH and CH. Significant differences in patient characteristics and surgical practices exist between surgical settings. Despite minimal differences in hospital-reported outcomes, the TH was significantly more expensive.

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THU0433 TREATMENT WITH PEGLOTICASE IMPROVES HEPATIC FIBROSIS ESTIMATED BY FIBROSIS-4 INDEX IN SUBJECTS WITH CHRONIC REFRACTORY GOUT

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.2360 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 454.1-454

Author(s):

N. Schlesinger ◽

A. Yeo ◽

P. Lipsky

Keyword(s):

Liver Disease ◽

Linear Regression ◽

Rank Order ◽

Linear Regression Analysis ◽

Area Under The Curve ◽

Serum Urate ◽

Complete Analysis ◽

Alcoholic Fatty Liver ◽

Significant Difference ◽

The Impact

Background:Hyperuricemia is associated with non-alcoholic fatty liver disease (NAFLD)1,2, but the relationship to fibrosis remains uncertain3. Moreover, it is not known whether lowering serum urate will affect the course of NAFLD. The availability of data from two randomized trials of pegloticase, a pegylated recombinant mammalian uricase, that profoundly decreases serum urate afforded the opportunity to test the hypothesis that lowering urate might improve NAFLD.Objectives:To determine whether treatment of chronic refractory gout patients with pegloticase was associated with improvement in NAFLD determined by Fibrosis 4 index (Fib4).Methods:Databases from patients with chronic refractory gout who participated in two randomized 6 month clinical trials (RCTs) of pegloticase were analyzed4. Sub-sets who had persistent urate lowering to levels <1 mg/dL in response to biweekly pegloticase (Responders, n=36) were compared to those who received placebo (n=43). Since liver biopsy information was not available on these subjects, we relied on Fib4, a validated non-invasive estimate of liver fibrosis in a variety of liver diseases5,6calculated from measurements of AST, ALT, platelet count and age (Age x AST/platelets x √ALT). A Fib4 value of 1.3 is an indication that further evaluation of liver disease is warranted.Results:At baseline, the mean Fib4 values were 1.40 ± 0.86 in pegloticase responders and 1.04 ± 0.53 in subjects receiving placebo. As shown in figure 1, subjects receiving placebo exhibited a change of 0.26 ± 0.41 in the Fib4 score over the six months of the RCTs compared with 0.13 ± 0.62 in the pegloticase responders (p=0.048; by linear regression). When only the subjects with a Fib4 value > 1.3 were considered, a significant difference in the change in the Fib4 values over the 6 months of the trial between pegloticase responders and those receiving placebo was also observed (-0.15 ± 0.67 vs 0.37 ± 0.42, p=0.004, by linear regression). The correlations between serum urate area under the curve (AUC) over the 6 months of the trial and the change in Fib4 value was rs=0.33, p=0.0.0004 (Spearman rank-order correlation coefficient). Finally, multiple linear regression analysis indicated serum urate AUC (as a surrogate measure for group) is the main contributor to the change in Fib4 (p=0.018 by linear regression).Conclusion:The data are consistent with the conclusion that persistent lowering of serum urate had a significant impact on Fib4 levels, implying a possible effect on the course of NAFLD. The results support a more complete analysis involving biopsy examination of the impact of urate on liver inflammation and fibrosis.References:[1]Yang C et al. PlosOne2017; 12:e0177249[2]Jaruvongvanich V et al. Eur J Gastroenterol Hepatol 2017; 29:1031[3]Jaruvongvanich V et al. Eur J Gastroenterol Hepatol 2017; 29:694[4]Sundy JS, et al. JAMA. 2011; 306 (7):711-20[5]Sterling RK et al. Hepatol 2006; 43:1317[6]Shah AG et al. Clin Gastroenterol Hepatol 2009;7:1104Disclosure of Interests: :Naomi Schlesinger Grant/research support from: Pfizer, Amgen, Consultant of: Novartis, Horizon Therapeutics, Selecta Biosciences, Olatec, IFM Therapeutics, Mallinckrodt Pharmaceuticals, Anthony Yeo Employee of: Horizon Therapeutics, Peter Lipsky Consultant of: Horizon Therapeutics

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Management of Ankle Fractures with Syndesmotic Disruption: A Survey of Orthopaedic Surgeons

Foot & Ankle Orthopaedics ◽

10.1177/2473011420s00408 ◽

2020 ◽

Vol 5 (4) ◽

pp. 2473011420S0040

Author(s):

Ryan G. Rogero ◽

Emmanuel M. Illical ◽

Daniel Corr ◽

Steven M. Raikin ◽

James Krieg ◽

...

Keyword(s):

Gold Standard ◽

Ankle Fracture ◽

Management Strategies ◽

Ankle Fractures ◽

Multinomial Regression ◽

Orthopaedic Surgeons ◽

Suture Button ◽

Standard Management ◽

Management Protocol ◽

Usage Patterns

Category: Ankle; Trauma Introduction/Purpose: With an increasing frequency of syndesmotic fixation during ankle fracture ORIF and no current gold standard management protocol, it is important for surgeons to understand the frequency and usage patterns of the various techniques among other orthopaedic surgeons. The purposes of this study are to determine how orthopaedic surgeons currently manage ankle fractures with concomitant syndesmotic disruption and to identify surgeon demographics predictive of syndesmotic management. Methods: An 18-question survey, including 10 specific syndesmotic management questions was sent to the Orthopaedic Trauma Association (OTA) and Canadian Orthopaedic Association (COA), as well as sent to email addresses of foot and ankle-fellowship trained surgeons. Surgeon demographic questions included years, country, and type of practice, fellowship(s) completed, setting of ankle fracture surgery, and number of ankle fractures operated on per year. Multinomial regression analysis was performed to determine if surgeon demographics were predictive of syndesmotic management. Results: One-hundred ten orthopaedic surgeons completed our survey. Selected predictors of syndesmotic management included: private practice with academic appointments (0.077 [0.007, 0.834]; p=0.035) being predictive of not using screws through an ORIF plate; foot & ankle fellowship (9.981 [1.787, 55.764]; p=0.009) and trauma fellowship (6.644 [1.302, 33.916]; p=0.023) predictive of utilizing screws through a plate; no fellowship (14.886 [1.226, 180.695]; p=0.034) predictive of only using 1 screw; and surgeons practicing in the U.S. were more likely to not use screws across just 3 cortices (0.031 [0.810, 3.660]; p=0.009). Additionally, among those utilizing suture-button devices, foot & ankle fellowship-trained surgeons were more likely to implement suture-button through plate (7.676 [1.286, 45.806]; p=0.025). Conclusion: Several surgeon factors influence decision making in the management of ankle fractures with syndesmotic disruption. This study raises awareness of differences in management strategies that should be used for further discussion when determining a potential gold standard for management of these complex injuries.

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How Many Proximal Screws Are Needed for a Stable Proximal Humerus Fracture Fixation?

Geriatric Orthopaedic Surgery & Rehabilitation ◽

10.1177/2151459321992744 ◽

2021 ◽

Vol 12 ◽

pp. 215145932199274

Author(s):

Hyojune Kim ◽

Myung Jin Shin ◽

Erica Kholinne ◽

Janghyeon Seo ◽

Duckwoo Ahn ◽

...

Keyword(s):

Cyclic Loading ◽

Proximal Humerus Fracture ◽

Locking Plate ◽

Proximal Humerus ◽

Humerus Fracture ◽

Proximal Fragment ◽

Maximum Displacement ◽

Significant Difference ◽

Load To Failure ◽

Screw Group

Purpose: This biomechanical study investigates the optimal number of proximal screws for stable fixation of a 2-part proximal humerus fracture model with a locking plate. Methods: Twenty-four proximal humerus fracture models were included in the study. An unstable 2-part fracture was created and fixed by a locking plate. Cyclic loading and load-to-failure tests were used for the following 4 groups based on the number of screws used: 4-screw, 6-screw, 7-screw, and 9-screw groups. Interfragmentary gaps were measured following cyclic loading and compared. Consequently, the load to failure, maximum displacement, stiffness, and mode of failure at failure point were compared. Results: The interfragmentary gaps for the 4-screw, 6-screw, 7-screw, and 9-screw groups were significantly reduced by 0.24 ± 0.09 mm, 0.08 ± 0.06 mm, 0.05 ± 0.01 mm, and 0.03 ± 0.01 mm following 1000 cyclic loading, respectively. The loads to failure were significantly different between the groups with the 7-screw group showing the highest load to failure. The stiffness of the 7-screw group was superior compared with the 6-screw, 9-screw, and 4-screw groups. The maximum displacement before failure showed a significant difference between the comparative groups with the 4-screw group having the lowest value. The 7-screw group had the least structural failure rate (33.3%). Conclusion: At least 7 screws would be optimal for proximal fragment fixation of proximal humerus fractures with medial comminution to minimize secondary varus collapse or fixation failure. Level of Evidence: Basic science study.

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