Proximal Humerus Reconstruction for Bone Sarcomas: A Critical Analysis.

¼ The proximal humerus is a common location for primary bone tumors, and the goal of surgical care is to obtain a negative margin resection and subsequent reconstruction of the proximal humerus to allow for shoulder function.¼ The current evidence supports the use of reverse total shoulder arthroplasty over hemiarthroplasty when reconstructing the proximal humerus after resection of a bone sarcoma if the axillary nerve can be preserved.¼ There is a lack of high-quality data comparing allograft prosthetic composite (APC) with endoprosthetic reconstruction of the proximal humerus.¼ Reverse APC should be performed using an allograft with donor rotator cuff to allow for soft-tissue repair of the donor and host rotator cuff, leading to improvements in shoulder motion compared with an endoprosthesis.

Comparative Complications Associated With BMP Use In Patients Undergoing ACDF for Degenerative Spinal Conditions: Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic Review and Meta-Analysis. OBJECTIVES: To compare complication incidence in patients with or without the use of recombinant human Bone Morphogenic Protein-2 (BMP2) undergoing anterior cervical discectomy and fusion (ACDF) for degenerative conditions. METHODS: A systematic search of eight online databases was conducted using PRISMA guidelines. Inclusion criteria included English language studies with a minimum of 10 adult patients undergoing instrumented ACDF surgery for a degenerative spinal condition in which BMP2 was used in all patients or one of the treatment arms. Studies with patients undergoing circumferential fusions, with non-degenerative indications, or which did not report post-operative complication data were excluded. Patients with and without BMP2 were compared in terms of the incidence of dysphagia/dysphonia, anterior soft tissue complications (hematoma, seroma, infection, dysphagia/dysphonia), nonunion, medical complications, and new neurologic deficits. RESULTS: Of 1832 preliminary search results, 27 manuscripts were included. Meta-analysis revealed the relative risk of dysphagia or dysphonia (RR = 1.39, CI 95% 1.18 - 1.64, P = <.001), anterior soft tissue complications (RR = 1.43, CI 95% 1.25-1.64, P = <.001), and medical complications (RR = 1.32, CI 95% 1.06-1.66, P = .013) were statistically significant in the BMP2 group while the relative risk of non-union (RR = .5, CI 95% .23 - 1.13, P = .09) trended lower in the BMP2 group. Neurological deficit (RR = 1.06, CI 95% .82-1.37, P = .66), and additional medical complications (RR = 1.53, CI 95% .98-2.38, P = .06) were not found to be statistically different between the groups. CONCLUSIONS: This meta-analysis identified a high rate of arthrodesis when BMP2 was used in ACDF, but confirmed increased rates of dysphagia and anterior soft tissue complications. Surgeons may consider reserving BMP2 implementation for cases with a high risk of non-union, and should be aware of the risk of airway compromise.

Sacral insufficiency fractures are a frequent and painful consequence of pubic symphysis osteomyelitis.

BACKGROUND: Pubic symphysis osteomyelitis can result from urosymphyseal fistula formation. High rates of sacropelvic insufficiency fractures have been reported in this population. The aim of this study was to describe the presentation and risk factors for sacral insufficiency fractures (SIF) associated with surgical treatment of pubic symphysis osteomyelitis. METHODS: A retrospective review was performed for 54 patients who underwent surgery for pubic symphysis osteomyelitis associated with a urosymphyseal fistula at a single institution from 2009 to 2022. Average age was 71 years and 53 patients (98%) were male. All patients underwent debridement or partial resection of the pubic symphysis at the time of fistula treatment. Average width of the symphyseal defect was 65 mm (range 9-122) after treatment. RESULTS: Twenty patients (37%) developed SIF at a mean time of 4 months from osteomyelitis diagnosis. Rate of sacral fracture on Kaplan-Meier analysis was 31% at 6 months, 39% at 12 months, and 41% at 2 years. Eleven patients developed SIF prior to pubic debridement and 12 patients developed new or worsening of pre-existing SIF following surgery. Width of pubic resection was higher in patients who developed SIF (76 mm vs. 62 mm), but this did not meet statistical significance (p = 0.18). CONCLUSION: Sacral insufficiency fracture is a common sequela of pubic symphysis osteomyelitis. These fractures are often multifocal within the pelvis and can occur even prior to pubic resection. Pubectomy further predisposes these patients to fracture. Clinicians should maintain a high index of suspicion for these injuries in patients with symphyseal osteomyelitis.

Durability of intercalary endoprosthesis for humeral reconstruction.

INTRODUCTION: The humerus is a common site of metastases and primary tumors. For some patients with a segmental defect and/or diaphyseal cortical destruction a cemented intercalary device may provide a more reliable construct, however data on their use is limited. METHODS: We reviewed 43 (28 male and 15 female) patients treated with an intercalary humeral spacer at a single tertiary referral center between 1989 and 2022. Humeral lesions were most commonly secondary to metastatic disease (n = 29, 68%), with 25 (58%) patients presenting with a pathologic fracture. Mean age and body mass index were 66 years and 27.9 kg/m2 . First generation taper joint device were used in 22 patients and second-generation lap device in 21 patients. RESULTS: Following reconstruction the 2-year overall survival was 30%. Mechanical complications occurred in 11 patients, most commonly aseptic loosening (n = 6, 14%). With death as a competing risk, the cumulative incidence of mechanical failure was 28% at 2-years postoperative. Following the procedure, mean Musculoskeletal Tumor Society scores was 70% and mean shoulder elevation was 87°. CONCLUSION: Reconstruction of the humeral diaphysis with an intercalary endoprosthesis provides restoration of function of the upper extremity, however, is associated with one in four patients having mechanical failure.

Reconstruction following oncological iliosacral resection.

Aims: The sacroiliac joint (SIJ) is the only mechanical connection between the axial skeleton and lower limbs. Following iliosacral resection, there is debate on whether reconstruction of the joint is necessary. There is a paucity of data comparing the outcomes of patients undergoing reconstruction and those who are not formally reconstructed. Methods: A total of 60 patients (25 females, 35 males; mean age 39 years (SD 18)) undergoing iliosacral resection were reviewed. Most resections were performed for primary malignant tumours (n = 54; 90%). The mean follow-up for surviving patients was nine years (2 to 19). Results: Overall, 27 patients (45%) were reconstructed, while 33 (55%) had no formal reconstruction. There was no difference in the use of chemotherapy (p = 1.000) or radiotherapy (p = 0.292) between the groups. Patients with no reconstruction had a mean larger tumour (11 cm (SD 5) vs 8 cm (SD 4); p = 0.014), mean shorter operating times (664 mins (SD 195) vs 1,324 mins (SD 381); p = 0.012), and required fewer blood units (8 (SD 7) vs 14 (SD 11); p = 0.012). Patients undergoing a reconstruction were more likely to have a deep infection (48% vs 12%; p = 0.003). Nine reconstructed patients had a hardware failure, with five requiring revision. Postoperatively 55 (92%) patients were ambulatory, with no difference in the proportion of ambulatory patients (89% vs 94%; p = 0.649) or mean Musculoskeletal Tumor Society Score (59% vs 65%; p = 0.349) score between patients who did or did not have a reconstruction. The ten-year disease-specific survival was 69%, with no difference between patients who were reconstructed and those who were not (78% vs 45%; p = 0.316). There was no difference in the rate of metastasis between the two groups (hazard ratio (HR) 2.78; p = 0.102). Conclusion: Our results demonstrate that SIJ reconstruction is associated with longer operating times, greater need for blood transfusion, and more postoperative infections, without any improvement in functional outcomes when compared to patients who did not have formal SIJ reconstruction.

Oncological and functional outcomes after resection of malignant tumours of the scapula.

Aims: The scapula is a rare site for a primary bone tumour. Only a small number of series have studied patient outcomes after treatment. Previous studies have shown a high rate of recurrence, with functional outcomes determined by the preservation of the glenohumeral joint and deltoid. The purpose of the current study was to report the outcome of patients who had undergone tumour resection that included the scapula. Methods: We reviewed 61 patients (37 male, 24 female; mean age 42 years (SD 19)) who had undergone resection of the scapula. The most common resection was type 2 (n = 34) according to the Tikhoff-Linberg classification, or type S1A (n = 35) on the Enneking classification. Results: The ten-year disease-specific survival was 76%. High tumour grade (hazard ratio (HR) 4.27; p = 0.016) and a total resection of the scapula (HR 3.84; p = 0.015) were associated with worse survival. The ten-year metastasis-free and local recurrence-free survivals were 82% and 86%, respectively. Total scapular resection (HR 6.29; p = 0.004) was associated with metastatic disease and positive margins were associated with local recurrence (HR 12.86; p = 0.001). At final follow-up, the mean shoulder forward elevation and external rotation were 79° (SD 62°) and 27° (SD 25°), respectively. The most recent functional outcomes evaluated included the mean Musculoskeletal Tumor Society Score (76% (SD 17%)), the American Shoulder and Elbow Score (73% (SD 20%)), and the Simple Shoulder Test (7 (SD 3)). Preservation of the glenoid (p = 0.001) and scapular spine (p < 0.001) improved clinical outcomes; interestingly, preservation of the scapular spine without the glenoid improved outcomes (p < 0.001) compared to preservation of the glenoid alone (p = 0.05). Conclusion: Resection of the scapula is a major undertaking with an oncological outcome related to tumour grade, and a functional outcome associated with the status of the scapular spine and glenoid. Positive resection margins are associated with local recurrence.

Multidisciplinary Treatment of Merkel Cell Carcinoma of the Extremities: Outcomes and Factors Associated with Poor Survival in Nodal Disease.

Merkel cell carcinoma (MCC) has a tendency for lymphatic spread and locoregional recurrence, although there is little data examining the risk factors for patients with lymph node-positive extremity lesions. The purpose of the current study was to examine the outcomes and risk factors associated with nodal metastasis in extremity MCC. We retrospectively reviewed the medical record of 120 patients with extremity MCC evaluated at our institution between 1994 and 2021. The mean age of this cohort was 71 years; 33% of patients were female; and 98% were Caucasian. Seventy-eight (65%) patients presented with localized disease. Thirty-seven (31%) patients had stage III disease, and five (4%) patients had stage IV disease. Treatment of primary lesions consisted primarily of margin-negative excision and adjuvant radiotherapy. Nodal metastases were most treated with adjuvant radiation or completion lymph node dissection. Five-year disease-specific survival in our series was 88% for patients with localized disease, 89% for stage IIIa disease, 40% for stage IIIb disease and 42% for stage IV. Factors associated with worse survival included immunosuppression and macroscopic nodal disease. In conclusion, extremity MCC has a low rate of local recurrence when treated with margin-negative excision and adjuvant radiation. However, treatment of nodal metastases remains a challenge with high rates of recurrence and mortality, particularly for patients who are immunosuppressed or who have macroscopic nodal disease.

Can the American Joint Replacement Registry Utilize Administrative Claims Data to Accurately Classify Revision Total Hip Arthroplasty (THA) Surgical Diagnoses?

BACKGROUND: The American Joint Replacement Registry (AJRR) is a valuable tool for studying revision total hip arthroplasty (rTHA). Currently, International Classification of Diseases-10 (ICD-10) codes are utilized by the AJRR for classifying surgical diagnoses. However, the validity of this methodology is unknown. The purpose of this study was to determine the accuracy of these codes, as used by AJRR, in classifying rTHA diagnoses. METHODS: We identified 908 rTHAs performed at our institution from 2015 to 2021 using our total joint registry (TJR). Revision diagnoses were obtained from the TJR, which contains prospectively recorded surgical diagnoses collected by trained abstractors, independent from ICD-10 data. The ICD-10 diagnosis codes, as submitted to AJRR, were retrieved for the same procedures. The accuracy of ICD-10 codes for classifying rTHA diagnoses as septic versus aseptic, instability, aseptic loosening, and periprosthetic fracture was assessed using Cohen's Kappa statistic, sensitivity, and specificity. RESULTS: Concordance between AJRR-submitted data and TJR for classifying rTHA as septic or aseptic was excellent (96.9%; k = 0.87). Agreement for aseptic diagnoses varied from very good for instability (k = 0.76) and loosening (k = 0.67) to moderate for periprosthetic fracture (k = 0.54). Specificity was high (>96%) for all 3 aseptic diagnoses, but sensitivity was lower at 74%, 68%, and 44% for instability, loosening, and periprosthetic fracture, respectively. CONCLUSION: The AJRR submitted ICD-10 data correctly classifies the infection status of rTHA procedures with outstanding accuracy, but the accuracy for more granular diagnoses was variable. These data demonstrate the potential for diagnosis specific limitations when utilizing ICD-10 administrative claims for registry reporting.

Is Bone Marrow Aspiration and Biopsy of Clinical Importance in the Initial Staging of Extraskeletal Ewing Sarcoma?

BACKGROUND: Extraskeletal Ewing sarcoma are rare tumors within the Ewing sarcoma family. Initial staging studies for extraskeletal Ewing sarcoma historically have included imaging and bone marrow aspiration and biopsy (BMAB). However, recent studies on Ewing sarcoma of bone have questioned the utility of BMAB in the initial staging of patients, but no studies of which we are aware have evaluated the role of BMAB in extraskeletal Ewing sarcoma. We suspected that BMAB was of low diagnostic yield in patients with extraskeletal Ewing sarcoma and exposed patients to potential morbidity without an impact on their clinical course. QUESTION/PURPOSE: Is BMAB a useful test in the staging of extraskeletal Ewing sarcoma? METHODS: Between January 1996 and December 2021, our institution evaluated 109 patients with a listed diagnosis of extraskeletal Ewing sarcoma. Those patients were retrospectively reviewed for this study. Of those, we considered patients with biopsy-confirmed diagnosis of extraskeletal Ewing sarcoma. Biopsy was performed based on institutional protocols, with all diagnoses assigned by a board-certified pathologist. Based on that criteria, 96% (105 of 109) were eligible. An additional 18% (20 of 109) were excluded because records of their initial diagnostic and staging workup were not available. This left 78% (85 of 109) for analysis. Of those, 52% (44 of 85) were male. The average age was 32 ± 16 years. Primary tumor locations included extremities in 26% (22 of 85), paraspinal in 20% (17 of 85), chest in 19% (16 of 85), retroperitoneum in 13% (11 of 85), intraabdominal in 12% (10 of 85), intrapelvic in 7% (6 of 85), and head or neck in 4% (3 of 85). Initial diagnostic and staging information, including the use of PET-CT, bone scan, CT chest, and BMAB, was collected. Metastatic disease at the time of presentation or during follow-up was noted. The utility of BMAB was determined by the rate of positive tests in those undergoing BMAB during the initial staging process. Descriptive statistical analysis was sufficient to address the study question, and therefore no comparative statistics were performed. RESULTS: BMAB was obtained during the initial staging process in 64% (54 of 85) of patients. This BMAB was negative in all 54 patients, including those with known metastatic disease. CONCLUSION: Diagnosing metastatic disease in extraskeletal Ewing sarcoma is important as the presence of metastases at diagnosis adversely affects prognosis. The routine use of BMAB in the staging process of extraskeletal Ewing sarcoma is of low diagnostic yield. BMAB is unlikely to diagnose metastatic involvement even in patients with known metastases to bone. We do not have enough data to suggest whether other modalities, such as PET-CT, might be more useful. Similar studies should be pursued to determine the utility of the remainder of staging modalities in patients with extraskeletal Ewing sarcoma to elucidate the most efficient and effective staging protocol. LEVEL OF EVIDENCE: Level III, diagnostic study.

Does Shorter Time to Treatment of Pediatric Supracondylar Humerus Fractures Impact Clinical Outcomes?

BACKGROUND: Treatment of supracondylar humerus (SCH) fractures within 18 hours of presentation is a tracked quality metric for ranking of pediatric hospitals. This is in contrast with literature that shows time to treatment does not impact outcomes in SCH fractures. We aim to determine whether an 18-hour cutoff for pediatric supracondylar humerus fracture treatment is clinically significant by comparing the complication risks ofpatients on either side of this timepoint. Our hypothesis is that there will be no statistically significant differences based on time to treatment. METHODS: A retrospective review of clinical outcomes was performed for 472 pediatric patients who underwent surgical management of isolated supracondylar humerus fractures between 1997 and 2022 at a single level I pediatric trauma hospital. The cohort was split based on time to surgery (within or ≥18 h from Emergency Department admission). RESULTS: Surgical treatment occurred within 18 hours of arrival in 435 (92.2%) patients and after 18 hours in 37 (7.8%) patients. Mean age was 5.6±2.2 years and 51.5% of patients were female. Gartland fracture classification was type II [n=152 (32.3%)], type III [n=284 (60.3%)], type IV [n=13 (2.8%)], or flexion-type [n=18 (3.8%)]. There were no differences in demographic characteristics or fracture classification between cohorts. Fractures in the ≥18-hour cohort were treated more commonly with 2 pins (62.2% vs. 38.5%, P =0.04). There were no statistically significant differences in open versus closed reduction, utilization of medial pins, or postoperative immobilization between cohorts. We were unable to detect any differences in postoperative complications, including non-union, delayed union, stiffness, malunion, loss of reduction, iatrogenic nerve injury, or infection. This remained true when type II fractures were excluded. CONCLUSIONS: Using an arbitrary time cutoff of <18 hours does not influence clinical outcomes in the surgical treatment of SCH fractures. This held true when type II fractures were excluded. For this reason, we recommend modification to the USNWR guidelines to decrease emphasis on time-to-treatment of SCH fractures. LEVEL OF EVIDENCE: Level III.

Is the American Joint Replacement Registry Able to Correctly Classify Revision Total Knee Arthroplasty Procedural Diagnoses?

BACKGROUND: The American Joint Replacement Registry (AJRR) is a powerful tool for the study of revision total knee arthroplasty (rTKA). The AJRR uses International Classification of Diseases-10 (ICD-10-CM) codes for recording surgical diagnoses. However, the validity of this methodology is unknown. The purpose of this study was to determine the accuracy of ICD-10-CM codes, as used by AJRR, in classifying rTKA diagnoses. METHODS: There were 988 rTKAs performed from 2015 to 2021 identified in our institutional total joint registry (TJR). Revision diagnoses were obtained from TJR, in which trained abstractors prospectively record diagnoses independent of ICD-10-CM data. The ICD-10-CM diagnosis codes submitted to AJRR were retrieved for the same procedures. The accuracy of ICD-10-CM codes for classifying rTKA diagnoses as septic versus aseptic, aseptic loosening, instability, and periprosthetic fracture was assessed using Cohen's Kappa statistics, sensitivities, and specificities. RESULTS: Concordance between AJRR-submitted codes and TJR was excellent (97.3%, k = 0.9) for identifying septic versus aseptic revisions. Agreement for aseptic diagnoses varied from very good for loosening (k = 0.65) and instability (k = 0.64) to fair for periprosthetic fracture (k = 0.36). Specificity was high (> 94%) for all three diagnoses, but sensitivity was lower at 71%, 63%, and 28% for loosening, instability, and periprosthetic fracture, respectively. CONCLUSION: The AJRR submitted ICD-10-CM diagnosis codes correctly classified rTKA cases as septic or aseptic with remarkable accuracy, but accuracy for more granular diagnoses varied. These data demonstrate the potential for diagnosis-specific limitations when using administrative claims data for registry reporting and have important implications for researchers using ICD-10-CM data.

Outcome of Multidisciplinary Treatment of Merkel Cell Carcinoma of the Hand and Wrist.

BACKGROUND/AIM: Skin cancers are the most common malignancy of the hand and wrist. Merkel cell carcinoma (MCC) is a rare, aggressive non-melanoma skin cancer arising from cutaneous neuroendocrine cells and is known for local and distant recurrence. The purpose of the current study was to examine the treatment outcome of patients with MCC of the hand and wrist. PATIENTS AND METHODS: We reviewed 25 patients (18 males:7 females) with MCC that occurred in the hand and wrist. The mean age at the time of biopsy of 71±11 years. RESULTS: Tumors were located on the hand (n=13), finger/thumb (n=9), and wrist (n=3). Local control included wide local excision (n=22). This included 21 non-amputation resections and one 5th digit ray amputation. Sentinel lymph node biopsy was performed in 21 patients with positive nodal disease in seven cases. Adjuvant radiotherapy was delivered to the primary site in 17 patients and additionally to the regional lymph node basin in six patients. Recurrence within five years was noted in 40% of patients (mean time to recurrence 18.4±20.6 months). Recurrence-free and disease-specific survival rates at 5-years were 54.8% and 67.6%. CONCLUSION: MCC is a rare cutaneous neuroendocrine carcinoma with a high propensity for regional nodal spread. Despite aggressive local treatment, adjuvant radiotherapy to the primary site and regional nodes, MCC of the hand and wrist has a high rate of recurrence and mortality within five years of diagnosis.

Clinical risk factors associated with the development of adjacent segment disease in patients undergoing ACDF: A systematic review.

BACKGROUND CONTEXT: Cervical fusion for degenerative disorders carries a known risk of adjacent segment disease (ASD), a complication that often requires surgical intervention to relieve symptoms. Proposed risk factors for development of ASD include both clinical and radiographic patient characteristics. However, the true impact of these risk factors is less understood due to limitations in sample sizes and loss to follow-up in individual studies. PURPOSE: To review and critically examine current literature on the clinical risk factors associated with development of ASD in the cervical spine following ACDF. STUDY DESIGN: Systematic Review and Meta-Analysis. METHODS: We systematically reviewed the literature in December 2019 according to the PRISMA guidelines. Methodological quality of included papers and quality of evidence were evaluated according to MINORS and GRADE framework. Meta-analysis was performed to compute the odds ratio(OR)with corresponding 95% confidence interval(CI)for dichotomous data, and mean difference(MD) with 95% CI for continuous variables. RESULTS: 6,850 records were obtained using database query. Title/abstract screening resulted in 19 articles for full review, from which 10 papers met the criteria for analysis. There were no significant differences in gender (OR 0.99, 95% CI 0.75-1.30), BMI (MD -0.09, 95% CI -0.46 to 0.29), smoking (OR 1.13, 95% CI 0.80-1.59), alcohol (OR 1.07, 95% CI 0.70-1.64), diabetes (OR 0.85, 95% CI 0.56-1.31), number of segments fused (OR 0.86, 95% CI 0.64-1.16), and preoperative JOA (MD -0.50, 95% CI -1.04 to 0.04). Age (MD 3.21, 95% CI 2.00-4.42), congenital/developmental stenosis (OR 1.94, 95% CI 1.06-3.56), preoperative NDI (MD 4.18, 95% CI 2.11 to 6.26), preoperative VAS (neck) (MD 0.54 95% CI 0.09-0.99), and preoperative VAS (arm) (MD 0.98, 95% CI 0.43-1.34) were found to be statistically significant risk factors. CONCLUSION: Patients with congenital stenosis, advanced age, and high preoperative NDI are at increased risk of developing ASD.

Outcome of Scapular Ewing Sarcoma.

BACKGROUND/AIM: Ewing sarcoma is a common primary bone tumor, often located in the distal femur or pelvis. Although the scapula is a flat bone similar to the pelvis, scapular Ewing sarcoma is rare. The aim of this study was to review our institution's experience with the management of scapular Ewing sarcomas. PATIENTS AND METHODS: We reviewed 9 patients with an Ewing sarcoma of the scapula, which included 5 males and 4 females with a mean age of 19±6 years. All patients were treated with chemotherapy and local control. Local control included surgical resection (n=7) and definitive radiotherapy (n=2). Mean follow-up was 6 years. RESULTS: Prior to induction chemotherapy, the mean tumor size and volume were 10±2 cm and 181±112 cm3, respectively. Following induction chemotherapy, there was a reduction in the mean tumor size (6±3, p=0.02) and volume (20±12 cm3, p<0.01). The mean tumor necrosis in patients undergoing resection was 72±23%. The median survival was 30-months, and the 5-year disease specific survival was 38%. At most recent follow-up, the mean Musculoskeletal Tumor Society Score was 79±14%. CONCLUSION: Scapular Ewing sarcoma is a rare, aggressive tumor. Even with chemotherapy and local control with surgery or definitive radiotherapy, patient survival is poor.

Merkel cell carcinoma of unknown primary: Clinical presentation and outcomes.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy that usually occurs in the head/neck or extremities. However, there are reports of MCC developing in the lymph nodes or parotid gland without evidence of a primary cutaneous lesion. METHODS: We reviewed 415 patients with biopsy-proven MCC. Patients with MCC of unknown primary (n = 37, 9%, MCCUP) made up the study cohort. The primary endpoints of the study were rate of recurrence, disease-free survival, and overall survival. RESULTS: Patients with MCCUP presented with tumors in lymph nodes (n = 34) or parotid gland (n = 3). Nodal disease was most commonly detected in the inguinal/external iliac (n = 15) or axillary (n = 14) regions. The mean age at diagnosis was 70 years and 24% were female. Patients presented with distant metastases in 24.3% of cases. Patients with stage IIIA disease treated with regional lymph node dissection (RLND) had a lower risk of disease recurrence (hazard ratio 0.26, p = 0.046). Recurrence-free survival was 59.3% at 5 years. Disease-specific survival was 63.3% at 5 years. CONCLUSION: Patients with MCCUP have a high risk of recurrence and mortality. The optimal treatment for MCCUP has yet to be elucidated, although therapeutic RLND appears beneficial for these patients.

Improving Surgical Triage in Spine Clinic: Predicting Likelihood of Surgery Using Machine Learning.

BACKGROUND: Correctly triaging patients to a surgeon or a nonoperative provider is an important part of the referral process. Clinics typically triage new patients based on simple intake questions. This is time-consuming and does not incorporate objective data. Our goal was to use machine learning to more accurately screen surgical candidates seen in a spine clinic. METHODS: Using questionnaire data and magnetic resonance imaging reports, a set of artificial neural networks was trained to predict whether a patient would be recommended for spine surgery. Questionnaire responses included demographics, chief complaint, and pain characteristics. The primary end point was the surgeon's determination of whether a patient was an operative candidate. Model accuracy in predicting this end point was assessed using a separate subset of patients. RESULTS: The retrospective dataset included 1663 patients in cervical and lumbar cohorts. Questionnaire data were available for all participants, and magnetic resonance imaging reports were available for 242 patients. Within 6 months of initial evaluation, 717 (43.1%) patients were deemed surgical candidates by the surgeon. Our models predicted surgeons' recommendations with area under the curve scores of 0.686 for lumbar (positive predictive value 66%, negative predictive value 80%) and 0.821 for cervical (positive predictive value 83%, negative predictive value 85%) patients. CONCLUSIONS: Our models used patient data to accurately predict whether patients will receive a surgical recommendation. The high negative predictive value demonstrates that this approach can reduce the burden of nonsurgical patients in surgery clinic without losing many surgical candidates. This could reduce unnecessary visits for patients, increase the proportion of operative candidates seen by surgeons, and improve quality of patient care.

Clinical outcomes of latissimus dorsi tendon transfer and superior capsular reconstruction for irreparable rotator cuff tears: a systematic review.

BACKGROUND: Functionally irreparable rotator cuff tears (FIRCTs) present an ongoing challenge to the orthopedic surgeon. The aim of this systematic review was to critically compare the outcomes of three latissimus dorsi tendon transfer (LDT) techniques and two superior capsular reconstruction (SCR) techniques in treatment of FIRCTs. METHODS: A systematic review of studies evaluating the outcome of FIRCT treatment was performed via a search of four databases in April 2020. Each included study was reviewed in duplicate by two reviewers for evaluation of methodological quality. The treatments analyzed were arthroscopic LDT (aLDT), open LDT Gerber technique (oLDTG), open LDT L'Episcopo technique (oLDTL), SCR with allograft (SCR-Allo), and SCR with autograft (SCR-TFL). Demographics, range of motion, patient-reported outcome measures, radiographic acromiohumeral distance (AHD), treatment failures, and revisions were recorded. RESULTS: Forty-six studies (1287 shoulders) met criteria for inclusion. Twenty-three studies involved open latissimus transfer, with 445 shoulders undergoing oLDTG with mean follow-up of 63.2 months and 60 patients undergoing oLDTL with mean follow-up of 51.8 months. Ten studies (n = 369, F/U 29.2mo) reported on aLDT. Seven studies (n = 253, F/U 16.9mo) concerned SCR-Allo, and six studies (n = 160, F/U 32.mo) reported on SCR-TFL. Range of motion and subjective outcome scores improved in all techniques with no differences across treatments. Both SCR methods provided greater improvement in AHD than open LDT methods (p < 0.01). The re-tear rates were lower in both oLDT groups compared to the SCR groups (p = 0.03). Clinical failure rates were higher in the SCR-Allo and oLDTG groups, while overall treatment failures were lowest in oLDTL compared to all four other groups. CONCLUSION: SCR techniques were associated with improved short-term radiographic acromiohumeral distance, while the open LDT techniques had lower tendon re-tear and treatment failure rates. All techniques resulted in improved clinical outcomes and pain relief compared to preoperative levels with no differences across techniques. LEVEL OF EVIDENCE IV: Systematic review of case series and cohort studies.

Metformin Use Is Associated with Fewer Complications in Patients with Type-2 Diabetes Undergoing Total Knee Arthroplasty: A Propensity Score-Matched Analysis.

BACKGROUND: Diabetes is a well-established risk factor for complications following total knee arthroplasty (TKA), and the incidence of type-2 diabetes is increasing. Metformin is considered first-line therapy for type-2 diabetes and has been shown to reduce all-cause mortality and to possess anti-inflammatory properties. The impact of metformin use as it relates to outcomes following TKA is unknown. The purpose of this study was to investigate this relationship. METHODS: This is a retrospective cohort study using the Truven MarketScan database. Adult patients undergoing unilateral, primary TKA were identified. We included only patients with a preoperative diagnosis of type-2 diabetes and established 2 cohorts based on metformin status. Propensity score matching was performed to match patients who used metformin to those who did not (1-to-1). Patients were matched on factors including age, sex, insulin status, other diabetic medications, comorbidities, complexity of diabetes, and smoking status. Regression analysis was then performed on matched cohorts to examine 90-day outcomes. A subgroup analysis was performed on 1-year revision rates. RESULTS: After matching, there were 32,186 patients in both the metformin group and the no-metformin group, resulting in a total of 64,372 included patients. Baseline characteristics were similar between groups. Regression analysis, performed on matched cohorts, demonstrated that the no-metformin group had increased odds of readmission (odds ratio [OR], 1.09 [95% confidence interval (CI), 1.04 to 1.15]; p < 0.001), emergency department presentation (OR, 1.09 [95% CI, 1.04 to 1.14]; p < 0.001), extended length of stay (OR, 1.12 [95% CI, 1.06 to 1.15]; p < 0.001), periprosthetic joint infection (OR, 1.30 [95% CI, 1.13 to 1.50]; p < 0.001), deep vein thrombosis (OR, 1.17 [95% CI, 1.09 to 1.26]; p < 0.001), acute kidney injury (OR, 1.21 [95% CI, 1.09 to 1.33]; p < 0.001), hypoglycemic events (OR, 1.25 [95% CI, 1.01 to 1.54]; p = 0.039), and 1-year revision (OR, 1.16 [95% CI, 1.01 to 1.33]; p = 0.033). CONCLUSIONS: Metformin use in patients with type-2 diabetes undergoing TKA appears to be associated with lower odds of multiple complications and resource utilization parameters, including periprosthetic joint infection and 1-year revision rates. Given the frequency with which TKA is performed in patients with type-2 diabetes, this knowledge has the potential to improve optimization protocols and outcomes in this group of patients. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Management of shoulder instability in hypermobility-type Ehlers-Danlos syndrome.

Shoulder instability in hypermobile Ehlers-Danlos syndrome can result in lifelong pain and functional disability. Treatment in this population is complicated by the severe degree of instability as well as the underlying abnormalities of the joint connective tissue. Appropriate care for these patients requires a thorough understanding of the natural history of their disease, knowledge of the available treatment options, and certain special considerations. This article reviews the pathoanatomy, recognition, and management of shoulder instability in the patient with hypermobile Ehlers-Danlos syndrome.