Developmental loss, but not pharmacological suppression, of renal carbonic anhydrase 2 results in pyelonephritis susceptibility.

Carbonic anhydrase II knockout (Car2-/-) mice have depleted numbers of renal intercalated cells, which are increasingly recognized to be innate immune effectors. We compared pyelonephritis susceptibility following reciprocal renal transplantations between Car2-/- and wild-type mice. We examined the effect of pharmacological CA suppression using acetazolamide in an experimental murine model of urinary tract infection. Car2-/- versus wild-type mice were compared for differences in renal innate immunity. In our transplant scheme, mice lacking CA-II in the kidney had increased pyelonephritis risk. Mice treated with acetazolamide had lower kidney bacterial burdens at 6 h postinfection, which appeared to be due to tubular flow from diuresis because comparable results were obtained when furosemide was substituted for acetazolamide. Isolated Car2-/- kidney cells enriched for intercalated cells demonstrated altered intercalated cell innate immune gene expression, notably increased calgizzarin and insulin receptor expression. Intercalated cell number and function along with renal tubular flow are determinants of pyelonephritis risk.

Cell-specific qRT-PCR of renal epithelial cells reveals a novel innate immune signature in murine collecting duct.

The urinary tract is usually culture negative despite its close proximity to microbial flora. The precise mechanism by which the kidneys and urinary tract defends against infection is not well understood. The initial kidney cells to encounter ascending pathogens are the collecting tubule cells that consist of principal cells (PCs) that express aquaporin 2 (AQP2) and intercalated cells (ICs) that express vacuolar H+-ATPase (V-ATPase, B1 subunit). We have previously shown that ICs are involved with the human renal innate immune defense. Here we generated two reporter mice, VATPase B1-cre+tdT+ mice to fluorescently label ICs and AQP2-cre+tdT+ mice to fluorescently label PCs, and then performed flow sorting to enrich PCs and ICs for analysis. Isolated ICs and PCs along with proximal tubular cells were used to measure antimicrobial peptide (AMP) mRNA expression. ICs and PCs were significantly enriched for AMPs. Isolated ICs responded to uropathogenic Escherichia coli (UPEC) challenge in vitro and had higher RNase4 gene expression than control while both ICs and PCs responded to UPEC challenge in vivo by upregulating Defb1 mRNA expression. To our knowledge, this is the first report of isolating murine collecting tubule cells and performing targeted analysis for multiple classes of AMPs.

Extraction of high-quality RNA from human articular cartilage.

Extracting high-quality RNA from articular cartilage is challenging due to low cellularity and high proteoglycan content. This problem hinders efficient application of RNA sequencing (RNA-seq) analysis in studying cartilage homeostasis. Here we developed a method that purifies high-quality RNA directly from cartilage. Our method optimized the collection and homogenization steps so as to minimize RNA degradation, and modified the conventional TRIzol protocol to enhance RNA purity. Cartilage RNA purified using our method has appropriate quality for RNA-seq experiments including an RNA integrity number of ∼8. Our method also proved efficient in extracting high-quality RNA from subchondral bone.

Erythropoietin accelerates functional recovery after moderate sciatic nerve crush injury.

INTRODUCTION: Erythropoietin (EPO) has been identified as a neuroregenerative agent. We hypothesize that it may accelerate recovery after crush injury and may vary with crush severity. METHODS: Mice were randomized to mild, moderate, or severe crush of the sciatic nerve and were treated with EPO or vehicle control after injury. The sciatic function index (SFI) was monitored over the first week. Microstructural changes were analyzed by immunofluorescence for neurofilament (NF) and myelin (P0 ), and electron microscopy was used to assess ultrastructural changes. RESULTS: In moderate crush injuries, EPO significantly improved SFI at 7 days post-injury, an effect not observed with other severity levels. Increases in the ratio of P0 to NF were observed after EPO treatment in moderate crush injuries. Electron microscopy demonstrated endothelial cell hypertrophy in the EPO group. CONCLUSIONS: EPO accelerates recovery in moderately crushed nerves, which may be through effects on myelination and vascularization. Injury severity may influence the efficacy of EPO. Muscle Nerve 56: 143-151, 2017.

Differences in the Treatment of Distal Radius Fractures by Hand Fellowship Trained Surgeons: A Study of ABOS Candidate Data.

PURPOSE: The management of distal radius fractures differs based on the nature of the fracture and the experience of the surgeon. We hypothesized that patients requiring surgical intervention would undergo different procedures when in the care of a surgeon with subspecialty training in hand surgery as compared with surgeons with no subspecialty training in hand surgery. METHODS: We queried the ABOS database for case log information submitted for part II of the ABOS examination. Queries for all codes involved with distal radius fracture management were combined with associated codes for the management of median nerve neuropathy, triangular fibrocartilage complex tears, ulnar shaft, and styloid fractures. Hand fellowship trained orthopedic surgeons were compared with those completing other fellowships and non-fellowship trained orthopedic surgeons during their board collection period. RESULTS: During the study period, 2,317 orthopedic surgeons reported treatment of 15,433 distal radius fractures. Of these surgeons, 411 had hand fellowship training. On a per surgeon basis, fellowship trained hand surgeons operatively treated more multifragment intra-articular distal radius fractures than their non-hand fellowship trained counterparts (5.3 vs 1.2). Additional procedures associated with the management of distal radius fractures were also associated with the fellowship training of the treating surgeon. CONCLUSIONS: Among orthopedic surgeons taking part II of the ABOS certifying examination, differences exist in the type, management, and reporting of distal radius fractures among surgeons with different areas of fellowship training. CLINICAL RELEVANCE: This study describes the association of hand surgery fellowship training on the choice of intervention for distal radius fractures and associated conditions.

Erythropoietin Enhanced Recovery After Traumatic Nerve Injury: Myelination and Localized Effects.

PURPOSE: We previously found that administration of erythropoietin (EPO) shortens the course of recovery after experimental crush injury to the mouse sciatic nerve. The course of recovery was more rapid than would be expected if EPO's effects were caused by axonal regeneration, which raised the question of whether recovery was instead the result of promoting remyelination and/or preserving myelin on injured neurons. This study tested the hypothesis that EPO has a direct and local effect on myelination in vivo and in vitro. METHODS: Animals were treated with EPO after standard calibrated sciatic nerve crush injury; immunohistochemical analysis was performed to assay for myelinated axons. Combined in vitro neuron-Schwann cell co-cultures were performed to assess EPO-mediated effects directly on myelination and putative protective effects against oxidative stress. In vivo local administration of EPO in a fibrin glue carrier was used to demonstrate early local effects of EPO treatment well in advance of possible neuroregenerative effects. RESULTS: Systemic Administration of EPO maintained more in vivo myelinated axons at the site of nerve crush injury. In vitro, EPO treatment promoted myelin formation and protected myelin from the effects of nitric oxide exposure in co-cultures of Schwann cells and dorsal root ganglion neurons. In a novel, surgically applicable local treatment using Food and Drug Administration-approved fibrin glue as a vehicle, EPO was as effective as systemic EPO administration at time points earlier than those explainable using standard models of neuroregeneration. CONCLUSIONS: In nerve crush injury, EPO may be exerting a primary influence on myelin status to promote functional recovery. CLINICAL RELEVANCE: Mixed injury to myelin and axons may allow the opportunity for the repurposing of EPO for use as a myeloprotective agent in which injuries spare a requisite number of axons to allow early functional recovery.

No Differences in Clinical, Functional, or Patient-Reported Outcomes Following Trial of Nonoperative Management Before Open Reduction and Internal Fixation of Humeral Shaft Fractures.

OBJECTIVES: To test the hypothesis that primary osteosynthesis of humeral shaft fractures may lead to more favorable clinical, functional, and patient-reported outcomes than fixation following a trial of nonoperative management. DESIGN: Retrospective cohort review. SETTING: Academic level I trauma center. PATIENT SELECTION CRITERIA: Adult patients who presented with humeral shaft fractures and ultimately underwent open reduction and internal fixation (ORIF) from May 2011 to May 2021. Patients who underwent ORIF within 2 weeks of injury were grouped into the primary osteosynthesis cohort, and patients who underwent ORIF >4 weeks from the date of injury were grouped into the trial of nonoperative cohort. OUTCOME MEASURES AND COMPARISONS: Postoperative complications, elbow arc of motion, time to radiographic union, and patient-reported outcomes were investigated and compared between the primary osteosynthesis and trial of nonoperative management cohorts. RESULTS: One hundred twenty-seven patients fit the study criteria, 84 underwent primary osteosynthesis and 43 trialed initial nonoperative treatment. No differences were found in patient demographics between the primary osteosynthesis and trial of nonoperative management cohorts, including age (53 ± 19 vs. 57 ± 18; P = 0.25), sex (39% vs. 44% male, 61% vs. 56% female; P = 0.70), and Body Mass Index (BMI) (30 ± 6 vs. 32 ± 9; P = 0.38). The average time to operative intervention in the primary osteosynthesis group was 4 days (0-14 days) and 105 days (28-332 days) in the trial of nonoperative treatment group ( P < 0.01). No differences were found with regard to intraoperative blood loss, total operative time, time to radiographic union (determined using the Radiographic Union Scores for Humeral scoring system), or overall complication rates, including primary and secondary radial nerve injuries ( P = 0.23 and 0.86, respectively). Patients reported similar patient-reported outcomes measurement information system pain interference ( P = 0.73), depression (D) ( P = 0.99), and physical function ( P = 0.66) scores at their 6-month postsurgical follow-up visits. CONCLUSIONS: Patients who attempted a trial of nonoperative management for humeral shaft fractures before ORIF had similar clinical, functional, and patient-reported outcomes as those who underwent primary osteosynthesis. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Adjunctive dorsal spanning plate fixation for challenging distal radius injuries.

Background: Distal radius fractures with severely osteoporotic bone or articular comminution can provide challenges to fixation with traditional volar locked plating alone. The purpose of this study was to evaluate the clinical, radiographic, and patient reported outcomes of patients undergoing distal radius fixation with volar locked plating and adjunctive dorsal bridge plating. Methods: We retrospectively identified 16 patients with distal radius fractures who underwent our preferred surgical technique for fixation. Patients underwent volar locked plate fixation as well as dorsal bridge fixation at time of surgery. Seven patients were indicated for severe articular comminution with volar rim fragmentation (44%), three patients were revised for nonunion after previous volar locked late fixation (19%), and six patients had severely osteoporotic bone with articular comminution (38%). Two patients (13%) sustained AO/OTA 23-A3 distal radius fracture, two patients (13%) had a 23-B3 fracture, two patients (13%) had a 23-C2 fracture and ten patients (63%) had a 23-C3 fracture. Results: The average patient age was 51.8 years ± 20.6. Patients were followed for an average of 12.2±6.3 months. The dorsal bridge plate was removed at an average of 11.1±2.4 weeks. The average post-operative radial inclination was 18.9±2.4°, radial height 12.4 mm ± 2.6 mm, and volar tilt 7.1±1.9°. There were no cases of deep or superficial infection. After dorsal bridge plate removal, patients demonstrated an average wrist extension of 55.3±9.5°, flexion 54.4±12.8°, radial deviation 15.7±3.2°, 25.2±3.9 degrees of ulnar deviation. Conclusion: Distal radius fractures in the setting of severely osteoporotic bone, salvage procedures, articular comminution, volar rim fractures, and revision surgery present uniquely difficult surgical challenges. Volar locked plating with adjunctive dorsal bridge plating can be used with good short- and long-term results.

Greater Socioeconomic Deprivation is Associated with Increased Complication Rates and Lower Patient-Reported Outcomes Following Open Reduction and Internal Fixation of Humeral Shaft Fractures.

OBJECTIVES: This study explored the hypothesis that social determinants of health (SDOH), including racial and economic differences, may impact orthopaedic trauma outcomes in patients undergoing open reduction and internal fixation (ORIF) of humeral shaft fractures. METHODS: Design: Retrospective. SETTING: Single, academic, tertiary Level-I trauma center. PATIENT SELECTION CRITERIA: Adults with midshaft humerus fractures (AO/OTA 12) treated operatively with plate fixation from 05/2011 to 05/2021 with a minimum follow-up of nine months. OUTCOME MEASURES AND COMPARISONS: Radiographic fracture healing, complication rates, and patient-reported outcomes were investigated. SDOH were assessed using the Area Deprivation Index (ADI). Demographics, complications rates, and patient-reported clinical outcomes were compared between the first and fourth ADI quartiles. RESULTS: 196 patients fit the study criteria. The average age of the cohort was 47 years with 50 women (51%). Comparisons of the least deprived quartile (n=49) to the most deprived quartile (n=49) yielded similar sex distribution (59% vs 43% female, p=0.15), fewer non-white patients (8% vs 51%, p<0.01), older average age (51 years vs 43 years, p=0.05), similar BMI (30.5 vs. 31.8, p=0.45), and higher Charlson Comorbidity Index (CCI) (2.2 vs.1.1, p=0.03). While nonunion rates were similar (p=0.20) between groups, the most deprived quartile had 2.3 times greater odds of post-operative complications (p=0.04). Patients in the most deprived group exhibited higher PROMIS Pain Interference (PI) scores (p<0.01) and PROMIS Depression (D) scores (p=0.01), with lower PROMIS Physical Function (PF) scores (p<0.01) at 6-month follow-up than the least depriver cohort. The most deprived cohort had three times higher odds of missing scheduled appointments within the first post-operative year (p<0.01), resulting in a significantly higher no-show rate (p<0.01) than the least deprived cohort. Regression analysis including several demographic and injury factors identified that ADI was significantly associated with the occurrence of any missed appointments (p<0.01), no-show rates (p=0.04), and experiencing one of the following post-operative complications during recovery: Nonunion, radial nerve injury, or dysfunction (p=0.03). CONCLUSIONS: Patients experiencing greater resource deprivation faced increased odds of complications, missed appointments, and poorer PROMIS outcomes following humeral shaft fracture fixation, emphasizing that baseline socioeconomic disparities predict unfavorable post-operative outcomes even given favorable baseline health status according to the CCI score. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Primary Closure of External Fixator Pin Sites Is Safe After Orthopaedic Trauma Surgery.

OBJECTIVES: To determine if rates of pin site infection and surgical site infection among patients managed with primary closure after external fixator removal were similar to those allowed to heal secondarily. DESIGN: Retrospective cohort. SETTING: Urban/Suburban Academic Level I Trauma Center. PATIENT SELECTION CRITERIA: Patients who had received a lower extremity external fixator for provisional management before definitive fixation of lower extremity fractures were included with pin site wounds closed primarily or allowed to heal by secondary intention. OUTCOME MEASURES AND COMPARISONS: The rate of pin tract infection and surgical site infection following primary closure of external fixator pin sites relative to patients whose pin sites were allowed to heal through secondary intention. RESULTS: In total, 256 patients were evaluated: 143 patients (406 pin sites) in the primary closure group and 113 patients (340 in sites) in the secondary closure group. The average age was 49 ± 16 years. Sixty-five percent of included patients were male. There was no difference in pin tract infections between cohorts (primary = 0.5%, secondary = 1.5%, P = 0.26). External fixator duration in the primary closure group was 11.5 ± 8.4 days and 13.0 ± 8.1 days in the secondary closure group (P = 0.15). There was a greater rate of surgical site infections in the secondary intention cohort (15.9% vs. 7.7%, P = 0.047). CONCLUSIONS: There was no difference in pin site infection rate after primary pin site closure relative to patients who were allowed to heal through secondary intention. Furthermore, there was a lower rate of surgical site infection after primary closure. These results challenge the dogma of secondary closure for ex fix pin sites, suggesting that debridement and primary closure is a safe option for management of external fixator pin sites and may impart benefit in decreasing infection risk. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Reduction of Posterior Malleolus Fractures With Open Fixation Compared to Percutaneous Treatment.

Background: Operative decision making between approaches to posterior malleolus reduction remains a challenge. The purpose of this study is to compare the quality of reduction between percutaneous and open reduction of posterior malleolus fractures and to identify factors associated with malreduction. Methods: Operatively managed ankle fractures that included posterior malleolus fixation were reviewed. Fracture characteristics were determined on preoperative CT scans. Initial postoperative radiographs were used to measure reduction of the posterior malleolus articular surface and graded as satisfactory (<2 mm step-off) or malreduced (≥2 mm step-off). Final postoperative PROMIS scores and 1-year complications were compared between percutaneous and open cohorts. A multivariate stepwise regression model was used to evaluate predictors for malreduction. Results: A total of 120 patients were included. Open reduction was performed in 91 (75.8%) compared with 29 (24.2%) who underwent percutaneous reduction. Malreduction (≥2-mm articular step-off) occurred in 11.7% of patients. Malreduction rates were significantly higher with percutaneous fixation than open fixation (24.1% vs 7.7%, P = .02). Multiple fragments and those with ≥5 mm of displacement demonstrated higher malreduction rates with percutaneous fixation (P < .05 for both), whereas single fragments and those with <5 mm of displacement experienced similar malreduction rates with percutaneous or open fixation. Initial displacement ≥5 mm (relative risk [RR] = 3.8, 95% CI = 1.2-11.5, P = .02) and percutaneous treatment (RR = 4.1, 95% CI = 1.6-10.5, P < .01) were identified as independent risk factors for malreduction. There were no significant differences in 1-year complication rates or final PROMIS scores between groups. Conclusion: Open reduction of the posterior malleolus may lead to improved fracture reduction compared to percutaneous reduction without significant increase in complications. Open fixation improves reduction among fractures with multiple fragments or ≥5 mm of displacement, whereas fractures with a single fragment or <5 mm of displacement achieve similar reductions regardless of approach. Initial displacement ≥5 mm and percutaneous reduction are independent risk factors for malreduction. Level of evidence: Level III, therapeutic.

Increased Neighborhood Deprivation Is Associated with Prolonged Hospital Stays After Surgical Fixation of Traumatic Pelvic Ring Injuries.

BACKGROUND: The purpose of this study was to understand the role of social determinants of health assessed by the Area Deprivation Index (ADI) on hospital length of stay and discharge destination following surgical fixation of pelvic ring fractures. METHODS: A retrospective chart analysis was performed for all patients who presented to our level-I trauma center with pelvic ring injuries that were treated with surgical fixation. Social determinants of health were determined via use of the ADI, a comprehensive metric of socioeconomic status, education, income, employment, and housing quality. ADI values range from 0 to 100 and are normalized to a U.S. mean of 50, with higher scores representing greater social deprivation. We stratified our cohort into 4 ADI quartiles. Statistical analysis was performed on the bottom (25th percentile and below, least deprived) and top (75th percentile and above, most deprived) ADI quartiles. Significance was set at p < 0.05. RESULTS: There were 134 patients who met the inclusion criteria. Patients in the most deprived group were significantly more likely to have a history of smoking, to self-identify as Black, and to have a lower mean household income (p = 0.001). The most deprived ADI quartile had a significantly longer mean length of stay (and standard deviation) (19.2 ± 19 days) compared with the least deprived ADI quartile (14.7 ± 11 days) (p = 0.04). The least deprived quartile had a significantly higher percentage of patients who were discharged to a resource-intensive skilled nursing facility or inpatient rehabilitation facility compared with those in the most deprived quartile (p = 0.04). Race, insurance, and income were not significant predictors of discharge destination or hospital length of stay. CONCLUSIONS: Patients facing greater social determinants of health had longer hospital stays and were less likely to be discharged to resource-intensive facilities when compared with patients of lesser social deprivation. This may be due to socioeconomic barriers that limit access to such facilities. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Risk factors for loss of reduction following locked plate fixation of proximal humerus fractures in older adults.

PURPOSE: To identify characteristics associated with loss of reduction following open reduction and locked plate fixation (ORIF) of proximal humerus fractures in older adults and determine if loss of reduction affects patient reported outcomes (PROs), range of motion (ROM), and complication rates during the first postoperative year. METHODS: Patients >55 years old who underwent proximal humerus ORIF were reviewed. Patient and fracture characteristics were recorded. Fixation characteristics were measured on the initial postoperative AP radiograph including humeral head height (HHH) relative to the greater tuberosity (GT), head shaft angle (HSA), screw-calcar distance, and screw tip-joint surface distance. Loss of reduction was defined as GT displacement >5 mm or HSA displacement >10° on final follow up radiographs. Patient, fracture, and fixation characteristics were tested for association with loss of reduction. Outcomes including ROM, visual analog scale pain and PROMIS scores, and complication/reoperation rates during the first postoperative year were compared between those with or without loss of reduction. RESULTS: A total of 79 patients were identified, 23 (29.1%) of which had a loss of reduction. Calcar comminution (relative risk [RR]=2.5, 95% Confidence Interval [CI]=1.3-5.0, p<0.01), HHH <5 mm above GT (RR=2.0, CI=1.0-3.9, p = 0.048), and screw-calcar distance ≥12 mm (RR=2.1, CI=1.1-4.1, p = 0.03) were risk factors for loss of reduction. Upon multivariate analysis, calcar comminution was determined to be an independent risk factor for loss of reduction (RR=2.4, CI=1.2-4.7, p = 0.01). Loss of reduction led to higher complication (44% vs 13%, p<0.01) and reoperation rates (30% vs 7%, p<0.01), and decreased achievement of satisfactory ROM (>90° active forward flexion, 57% vs 82%, p = 0.02) compared to maintained reduction, but similar PROs. CONCLUSIONS: Calcar comminution, decreased HHH, and increased screw-calcar distance are risk factors for loss of reduction following ORIF of proximal humerus fractures. These morphologic and technical factors are important considerations for prolonged reduction maintenance.

Clinical Improvement Following Operative Management of Ankle Fractures Among Patients With and Without Moderate to High Depressive Symptoms: An Analysis Using PROMIS.

Background: Understanding the recovery trajectory following operative management of ankle fractures can help surgeons guide patient expectations. Further, it is beneficial to consider the impact of mental health on the recovery trajectory. Our study aimed to address the paucity of literature focused on understanding the recovery trajectory following surgery for ankle fractures, including in patients with depressive symptoms. Methods: From February 2015 to March 2020, patients with isolated ankle fractures were asked to complete Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF), Pain Interference (PI), and Depression questionnaires as part of routine care at presentation and follow-up time points. Linear mixed effects regression models were used to evaluate the patient recovery pattern, comparing the preoperative time point to <3 months, 3-6 months, and >6 months across all patients. Additional models that included the presence of depression symptoms as a covariate were then used. Results: A total of 153 patients met inclusion criteria. By 3-6 months, PROMIS PF (ß: 9.95, 95% CI: 7.97-11.94, P < .001), PI (ß: -10.30, 95% CI: -11.87 to -8.72, P < .001), and Depression (ß: -5.60, 95% CI: -7.01 to -4.20, P < .001) improved relative to the preoperative time point. This level of recovery was sustained thereafter. When incorporating depressive symptoms into our model as a covariate, the moderate to high depressive symptoms were associated with significantly and clinically important worse PROMIS PF (ß: -4.00, 95% CI: -7.00 to -1.00, P = .01) and PI (ß: 3.16, 95% CI: -0.55 to 5.76, P = .02) scores. Conclusion: Following ankle fracture surgery, all patients tend to clinically improve by 3-6 months postoperatively and then continue to appreciate this clinical improvement. Although patients with moderate to high depressive symptoms also clinically improve following the same trajectory, they tend to do so to a lesser level than those who have low depressive symptoms. Level of Evidence: Level III, case-control study.

Early Outcomes of Proximal Humerus Fractures in Adults Treated With Locked Plate Fixation Compared with Nonoperative Treatment: An Age-, Comorbidity-, and Fracture Morphology-Matched Analysis.

OBJECTIVES: To compare patient-reported outcomes (PROs), range of motion (ROM), and complication rates for proximal humerus fractures managed nonoperatively or with open reduction internal fixation (ORIF). DESIGN: Retrospective cohort. SETTING: Academic level 1 trauma center. PATIENTS/PARTICIPANTS: Four hundred thirty-one patients older than 55 years were identified retrospectively. 122 patients were excluded. 309 patients with proximal humerus fractures met inclusion criteria (234 nonoperative and 75 ORIF). After matching, 192 patients (121 nonoperative and 71 ORIF) were included in the analysis. INTERVENTION: Nonoperative versus ORIF (locked plate) treatment of proximal humerus fracture. MAIN OUTCOME MEASUREMENTS: Early Visual Analog Score (VAS), ROM, PROs, complications, and reoperation rates between groups. RESULTS: At 2 weeks, ORIF showed lower VAS scores, better passive ROM, and patient-reported outcomes measurement information system (PROMIS) scores ( P < 0.05) compared with nonoperative treatment. At 6 weeks, open reduction internal fixation (ORIF) had lower VAS scores, better passive ROM, and PROMIS scores ( P < 0.05) compared with nonoperative treatment. At 3 months, ORIF showed similar PROMIS scores ( P > 0.05) but lower VAS scores and better passive ROM ( P < 0.05) compared with nonoperative treatment. At 6 months, ORIF showed similar VAS scores, ROM, and PROMIS scores ( P > 0.05) compared with nonoperative treatment. There was no difference in secondary operation rates between groups ( P > 0.05). ORIF patients trended toward a higher secondary reoperation rate (15.5% vs. 5.0%) than nonoperative patients ( P = 0.053). CONCLUSIONS: In an age-, comorbidity-, and fracture morphology-matched analysis of proximal humerus fractures, ORIF led to decreased pain and improved passive ROM early in recovery curve compared with nonoperative treatment that normalized after 6 months between groups. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Superior Outcomes With Reverse Shoulder Arthroplasty versus Nonoperative Management for Proximal Humerus Fractures: A Matched Cohort Analysis.

OBJECTIVE: To evaluate early outcomes (within 1 year) for geriatric proximal humerus fractures managed nonoperatively or with reverse shoulder arthroplasty (RSA). DESIGN: Retrospective cohort. SETTING: Academic level 1 trauma center, level 2 trauma/geriatric fracture center. PATIENTS/INTERVENTION: Seventy-one patients with proximal humerus fractures that underwent nonoperative management or RSA, matched by age, comorbidity burden, and fracture morphology. MAIN OUTCOME MEASUREMENTS: Patient-reported outcomes, range of motion, and complications rates within 1 year of treatment. RESULTS: RSA patients demonstrated greater active forward flexion (aFF) and external rotation compared with nonoperative patients throughout the first 6 months after treatment ( P < 0.05 for all). RSA patients achieved satisfactory ROM (>90 degrees aFF) at higher rates than nonoperative patients (96.2% vs. 62.2%, P < 0.01). RSA led to significantly lower shoulder pain and PROMIS pain interference scores throughout the first year post-treatment ( P < 0.05). PROMIS physical function scores were also higher in the RSA group at 3 months, 6 months, and 1 year compared with the nonoperative group ( P < 0.05 for all). Similar complication rates were experienced in both groups (nonoperative = 8.9%, RSA = 7.7%; P = 0.36). CONCLUSIONS: In an age, comorbidity and fracture morphology matched analysis, treatment of proximal humerus fractures with RSA is associated with greater shoulder ROM throughout the first 6 months of treatment, decreased pain, and improved physical function compared with nonoperative management, without significant differences in short-term complications. These results suggest that RSA may be superior to nonoperative management during the early recovery period for proximal humerus fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Technique and Early Outcomes for High-Energy Calcaneus Fractures Treated With Staged External Fixation to Combined Open Reduction Internal Fixation and Subtalar Arthrodesis.

OBJECTIVE: (1) To present an effective surgical technique for the treatment of open and high-energy calcaneal fractures with significant soft tissue injuries. (2) To present complications with this technique and to evaluate patient-reported outcomes of staged external fixation followed by delayed reconstruction with open reduction internal fixation (ORIF) and subtalar arthrodesis. DESIGN: Retrospective case series. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: Twelve patients with 13 calcaneus fractures associated with open traumatic wounds (10 patients) or other severe soft tissue injury (ie, fracture blisters) between April 2013 and December 2019. INTERVENTION: All patients were treated with staged ankle-spanning external fixation and delayed reconstruction with ORIF with subtalar arthrodesis. MAIN OUTCOME MEASURES: Patient-Reported Outcomes Measurement Information System (PROMIS) outcomes are presented via the domains of physical function (PF), pain interference (PI), and depression (D) in addition to visual analog score. Complications with the injury and surgical procedure were reported as well. RESULTS: Patients underwent initial stabilization on average 1.3 days (range, 0-12 days) from injury with stage II occurring on average 31.1 days (range, 18-42 days) from external fixation. Mean time to radiographic union was 5.6 months (range, 4-10 months). One-year mean PROMIS outcomes were as follows: PF final average of 37.4 with an average improvement of 12.2 (P < 0.01), PI final average of 62.2 with average improvement of 5.6 (P = 0.01), and D final average of 52.1 with average improvement of 6 (P = 0.12). Mean final visual analog score pain score was 3.6 with an average improvement of 2.25 (P = 0.01). CONCLUSION: Staged treatment with initial external fixation followed by ORIF and subtalar arthrodesis in the setting of highly comminuted calcaneus fractures with significant soft tissue compromise effectively addresses both bony and soft tissue concerns while providing for positive outcomes postoperatively with regards to pain and function. There were minimal complications noted for this complex injury. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Outcomes for type C proximal humerus fractures in the adult population: comparison of nonoperative treatment, locked plate fixation, and reverse shoulder arthroplasty.

Background: This study compares patient-reported outcomes and range of motion (ROM) between adults with an AO Foundation/Orthopaedic Trauma Association type C proximal humerus fracture managed nonoperatively, with open reduction and internal fixation (ORIF), and with reverse shoulder arthroplasty (RSA). Methods: This is a retrospective cohort study of patients >60 years of age treated with nonoperative management, ORIF, or RSA for AO Foundation/Orthopaedic Trauma Association type 11C proximal humerus fractures from 2015 to 2018. Visual analog scale pain scores, Patient-Reported Outcomes Measurement Information System (PROMIS) scores, ROM values, and complication and reoperation rates were compared using analysis of variance for continuous variables and chi square analysis for categorical variables. Results: A total of 88 patients were included: 41 nonoperative, 23 ORIF, and 24 RSA. At the 2-week follow-up, ORIF and RSA had lower visual analog scale scores and lower PROMIS pain interference scores (P < .05) than nonoperative treatment. At the 6-week follow-up, ORIF and RSA had lower visual analog scale, PROMIS pain interference, and PF scores and better ROM (P < .05) than nonoperative treatment. At the 3-month follow-up, ORIF and RSA had better ROM and PROMIS pain interference and PF scores (P < .05) than nonoperative treatment. At the 6-month follow-up, ORIF and RSA had better ROM and PROMIS PF scores (P < .05) than nonoperative treatment. There was a significantly higher complication rate in the ORIF group than in the non-operative and RSA groups (P < .05). Conclusion: The management of AO Foundation/Orthopaedic Trauma Association type 11C proximal humerus fractures in older adults with RSA or ORIF led to early decreased pain and improved physical function and ROM compared to nonoperative management at the expense of a higher complication rate in the ORIF group.

Impingement in Insertional Achilles Tendinopathy Occurs Across a Larger Range of Ankle Angles and Is Associated With Increased Tendon Thickness.

BACKGROUND: Insertional Achilles tendinopathy (IAT) is characterized by tendon degeneration and thickening near the tendon-bone insertion.11 Calcaneal impingement is believed to contribute to the pathogenesis of IAT.5 However, it is unclear how increased tendon thickness in individuals with IAT influences impingement. This study aimed to compare Achilles tendon impingement in individuals with and without IAT. METHODS: Eight healthy adults and 12 adults with clinically diagnosed symptomatic IAT performed a passive flexion exercise during which ankle flexion angle, anterior-posterior (A-P) thickness, and an ultrasonographic image sequence of the Achilles tendon insertion were acquired. The angle of ankle plantarflexion at which the calcaneus first impinges the Achilles tendon, defined as the impingement onset angle, was identified by (1) a anonymized observer (visual inspection method) and (2) a computational image deformation-based approach (curvature method). RESULTS: Although the 2 methods provided different impingement onset angles, the measurements were strongly correlated (R2 = 0.751, P < .05). The impingement onset angle and the thickness of the Achilles tendon insertion were greater in subjects with clinically diagnosed IAT (P = .0048, P = .0047). Furthermore, impingement onset angle proved to have a moderate correlation with anterior-posterior thickness (R2 = 0.454, P < .05). CONCLUSION: Our findings demonstrated that increased tendon thickness in IAT patients is associated with larger impingement onset angles, raising the range of ankle angles over which the tendon is exposed to impingement. CLINICAL RELEVANCE: Increased susceptibility to impingement may exacerbate or perpetuate the pathology, highlighting the need for clinical strategies to reduce impingement in IAT patients.

Proximal Femoral Shortening and Varus Collapse After Fixation of "Stable" Pertrochanteric Femur Fractures.

OBJECTIVES: To evaluate and compare femoral neck shortening and varus collapse in stable pertrochanteric femur fractures treated with sliding hip screws (SHSs) or cephalomedullary nails (CMNs). DESIGN: Retrospective review. SETTING: Academic medical center. PATIENTS: A total of 290 patients were included in the study. The average age was 82 years, and most were women. All sustained low-energy pertrochanteric femur fractures (OTA/AO A1.1, 1.2, 1.3, 2.2) treated operatively with SHSs or CMNs. Minimum radiographic follow-up was 3 months, with an average of 28 (range 3-162) months. INTERVENTION: CMN or SHS fixation. MAIN OUTCOME MEASURES: Varus collapse of the femoral neck-shaft angle and proximal femoral shortening. RESULTS: Both implants allowed some varus collapse. Univariate analysis demonstrated a significantly greater portion of patients with SHSs progressed to varus collapse >5 degrees (P = 0.02), mild horizontal shortening >5 mm (P < 0.01), and severe horizontal shortening >10 mm (P < 0.01). There was no statistical difference in vertical shortening (P = 0.3). There was no difference in implant failure (P = 0.5), with failure rates of 3% for cephalomedullary implants and 5% for SHS constructs. CONCLUSIONS: The SHS group experienced greater varus collapse and horizontal shortening. There was no difference in overall implant failure. These findings suggest that the CMN is a superior construct for maintenance of reduction in stable pertrochanteric fractures, which may lead to improved functional outcomes as patients recover. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.