Radiographic Comparison of Forearm Symmetry in Healthy Individuals and its Importance in the Diagnosis of Longitudinal Radioulnar Dissociation.

PURPOSE: Longitudinal radioulnar dissociation (LRD) is an injury often missed upon initial presentation. A recent study examined a radiographic screening test in cadavers that showed increased interosseous distance when the interosseous ligament (IOL) was divided. For this test to be clinically useful, it is necessary for uninjured forearms to have similar interosseous spaces. The purpose of this study was to determine the typical differences between right and left interosseous spaces of healthy individuals. METHODS: Anterior-posterior x-rays of bilateral forearms in maximum supination of 28 surgical residents with no history of injury were obtained. These images were uploaded into a picture archiving and communication system and then digitized. The length of the radius was measured (Xr). The maximum interosseous distance (Dmax) between the radius and ulna as well as the interosseous distance at a location 0.3 Xr from the distal radioulnar joint was measured. The right and left arm distances were compared. Also, an outlier analysis was used to evaluate forearm rotational asymmetry between right and left arms. RESULTS: The outlier analysis revealed two sets of forearm x-rays were rotationally different compared to the rest of the group due to asymmetric arm positioning; these data were excluded from the analysis. The average difference in Dmax was 1.7 mm (standard deviation [SD] 1.5) between right and left arms, and this was found at a position of 0.28 Xr on average. The difference in interosseous distance measured at a fixed location 0.3 Xr was 1.6 mm (SD 1.5). No significant difference was found between the paired right and left arms for Dmax or at 0.3 Xr. CONCLUSIONS: There does not appear to be any significant difference between the maximum interosseous distance of right and left arms in healthy individuals. Therefore, analyzing bilateral forearm x-rays may be a simple LRD screening test. CLINICAL RELEVANCE: Understanding the degree of normal variation in the forearm bone spacing might inform evaluation of abnormal forearm bone alignment resulting from LRD.

Knee Pain and Functional Outcomes after Retrograde Femoral Nailing: A Retrospective Review.

Objectives: To investigate the incidence and severity of knee pain following retrograde intramedullary nailing of femur fractures and to better understand functional outcomes using validated patient-reported outcome measures. Methods: Fifty-three patients with OTA 32 or 33 fractures treated by retrograde nail at a single academic Level 1 trauma center between 2009 and 2020 were retrospectively reviewed. Patients verbally completed the Oxford Knee Score (OKS) and Patient-Reported Outcome Measurement Information System (PROMIS) Short Form 6b, minimum one year postoperatively. Results: Thirty-four (64%) patients reported the presence of pain. Of those reporting pain, 16 (47.1%) reported their pain as mild. Compared to those without pain, patients with knee pain had lower OKS (30.38 +/- 10.65, versus 41.95 +/- 6.87; P <0.001) and higher PROMIS scores (14.65 +/- 6.76 versus 10.95 +/- 7.09; P=0.066). Conclusion: The increasing severity of pain was inversely correlated with functional status as measured by patient-reported measures. At present, the reliability, high union rates, and otherwise low complication rates associated with retrograde femoral nailing justify its continued use. However, knee pain and functional outcomes should remain an integral part of the preoperative discussion with the patient.

Cefiderocol for Stenotrophomonas maltophilia prosthetic joint infection: a case report.

Treatment of Stenotrophonomas maltophilia infections is difficult due to its predilection to form biofilms and susceptibility to a limited number of antibiotics. We report a case of S. maltophilia-associated periprosthetic joint infection successfully treated with a combination of the novel therapeutic agent, cefiderocol, and trimethoprim-sulfamethoxazole after debridement and implant retention.

Characterization of the gut microbiome in an osteosarcoma mouse model.

Compelling evidence has mounted surrounding the relationship between the gut microbiome and many intestinal and extraintestinal cancers. Few studies exist investigating the relationship between the gut microbiome and sarcoma. We hypothesize that the presence of distant osteosarcoma induces change to the profile of flora within the mouse. Twelve mice were used for this experiment: six were sedated and received an injection of human osteosarcoma cells into the flank, while six served as controls. Baseline stool and weight were collected. Tumor size and mouse weight were recorded weekly, and stool samples were collected and stored. Fecal microbiomes of the mice were profiled by 16S rRNA gene sequencing and analyzed for alpha diversity, relative abundances of microbial taxa, and abundance of specific bacteria at different time points. Alpha diversity was increased in the osteosarcoma group compared with the control group. The family Lachnospiraceae had the second strongest negative net average change in relative abundance over time in the osteosarcoma group whereas it had a positive net average change in the control group. An increased Firmicutes/Bacteroidota (F/B) ratio was observed in the osteosarcoma group relative to the control mice. These differences suggest that there may be an interplay between the gut microbiome and osteosarcoma. Clinical significance: Due to the paucity of literature available, our work can support novel research on this relationship and the development of new, personalized treatments for osteosarcoma.

Preoperative Stereotactic Body Radiation Therapy for Soft-Tissue Sarcoma: Results of Phase 2 Study.

Purpose: Preoperative radiation followed by surgical resection is a standard treatment for soft-tissue sarcomas (STS). We report on 2 consecutive, phase 2, single-arm studies evaluating 5 fraction stereotactic body radiation therapy (SBRT) treatments followed by surgical resection for STS (clinical trails.gov NCT02706171). Methods and Materials: A total of 16 patients were treated with preoperative SBRT. Tumor size in the greatest dimension was a median 6.7 cm (maximum: 14 cm) and the majority of STS were in the extremities. SBRT consisted of 35 to 40 Gy in 5 fractions every other day. Results: Median follow-up time was 1719 days (4.7 years). Grade ≥3 acute toxicity occurred in 1 patient (grade 3 skin changes). Fifteen patients proceeded with surgical resection. Three patients had a wound complication after surgery, 1 patient had grade ≥3 late toxicity (grade 4 requiring surgical intervention). There was 1 local recurrence and 5 distant recurrences. Conclusions: Long-term follow-up on SBRT for STS found acceptable control and toxicity rates, and warrants further evaluation.

Reliability and accuracy in radiographic measurements of musculoskeletal tumors.

Tumor size and growth are important parameters when evaluating bone and soft tissue neoplasms. There are no reports comparing the intra- and interobserver reliability among physicians in their evaluation of musculoskeletal (MSK) tumor imaging. This study investigates the accuracy and precision of measurements made by orthopedic and radiology physicians in different stages of training. Blinded magnetic resonance imaging (MRI) scans from six patients, three soft tissue, and three bone tumors were selected: each case included an "old" and "new" scan that was performed at least 3 months apart. Fourteen participants were selected, representing varying levels of education and experience, including two of each of the following: medical students, orthopedic and radiology residents, oncology and nononcologic orthopedic attendings, and MSK and non-MSK radiology attendings. Participants compared the old and new studies, recording tumor size in the transverse, cranial-caudal, and anterior-posterior dimensions, and determined if the tumor was stable or unstable. The MRI's official report served as the "gold standard." Average intraobserver variability (|Trial 1 - Trial 2|/[(Trial 1 + Trial 2)/2])) in size measurements was 11.08% (0.00%-68.62%). The lowest variability was recorded by the MSK radiologist 1 (6.16%), and the greatest variability by Orthopedic Surgery Resident 1 (16.70%). Participants correctly determined stability 82% of the time (71%-100%). Only MSK radiologists correctly determined stability in over 90% of cases. There is considerable variability and inaccuracy in MRI-based measurements of MSK tumors. These findings motivate opportunities for improving MSK imaging education of radiology and orthopedic residents. Physicians ordering MRI scans should evaluate them themselves, instead of relying on the radiology report alone, to inform clinical decision-making.

Ancient Schwannoma with Hemorrhagic Degeneration Causing Chronic Intramuscular Hematoma: A Case Report.

Introduction: The value of this manuscript is that it highlights a common diagnostic challenge facing orthopedic surgeons, involving the reality that both benign and malignant soft-tissue tumors can present as large cystic masses masquerading as a hematoma. This is the first report of its kind to describe a schwannoma presenting as such a large hematoma in the thigh. Case Presentation: A 64-year-old male presented with 2 days of worsening pain over a left posterior thigh mass that was enlarging for 12 years. Imaging demonstrated a cystic mass. 1.8L of serosanguinous fluid was aspirated and cytology was negative for malignancy, suggesting chronic hematoma. The fluid reaccumulated, indicating surgical management. Histopathology revealed a hemorrhagic ancient schwannoma. Conclusion: Without history of trauma or anticoagulation, intramuscular hematoma should be a diagnosis of exclusion. Burden of proof is high to rule-out a neoplastic process masquerading as fluid collection. Biopsies should be taken and schwannoma with ancient change and cystic degeneration should be considered.

Intraosseous Lipoma: An Elusive Cause of Long Bone Pain: A Case Series.

Introduction: Intraosseous lipomas are benign tumors composed of mature fat that reside within the intramedullary canal. Although many cases are asymptomatic, some patients report pain that interferes with daily living. For patients presenting with refractory pain, surgical excision may be performed. These tumors were once thought to be rare, but a recent increase in awareness and diagnostic capability may contradict this. Case Presentations: A 27-year-old female presented with a 3-month history of deep and aching pain in her left shoulder. The second patient was a 24-year-old female who presented with a 3-year history of pain in her right tibia. The third was a 50 year old female who presented with a 4-month history of deep pain in her right humerus. The fourth patient was a 34-year-old female who presented with a 6-month history of the left heel pain. All were found to have intraosseous lipomas and were treated with excisional curettage, achieving resolution of symptoms. Conclusion: These cases may help orthopedists better understand the presentation and treatment of intraosseous lipomas due to several shared characteristics. We also hope that this report may lead clinicians to include this pathology in their differential diagnosis when patients present with similar symptoms. As the prevalence of these tumors appears to be increasing, efficient diagnosis and treatment will become increasingly valuable to orthopedists and patients.

The Delivery of Orthopaedic Care midst COVID-19 and Social Distancing.

In this paper we present the findings of a literature review covering articles published in the last three decades describing the application of telemedicine in orthopaedics. A review of the PubMed Central and Medline provided 75 articles studying the role of telemedicine, the majority directly examining the application of telemedicine in orthopaedic patients. We report the summarized findings of these studies, the financial and HIPAA considerations of using telemedicine, and provide an example of our single urban level-1 trauma center's strategy for incorporating telemedicine into the clinical practice of orthopaedic surgeons during the COVID-19 pandemic.

"Dry Arthroscopy" is a Valuable Tool in the Excisional Curettage of Chondroblastoma: A Case Series.

INTRODUCTION: Chondroblastomas are benign, locally aggressive bone tumors that occur in the epiphysis of young patients, requiring surgical excision. The anatomic locations of these lesions pose technical challenges to the surgeon; their proximity to the articular surface and the physis make surgical approach and visualization difficult. This case series describes the use of intramedullary arthroscopic assistance during excisional curettage of three distal femoral chondroblastomas. CASE REPORT: Three patients with distal femoral chondroblastomas underwent excisional curettage with intraosseous "dry" arthroscopic assistance. We describe a two-tunnel technique, using medial and lateral windows so the arthroscope and working instruments could be within the lesion simultaneously; as well as two variations of a single-tunnel technique. CONCLUSION: Achieving adequate ex---posure and visualization, while protecting the articular surface and physis, during excision of chondroblastomas, is essential for avoiding local recurrence and complications. "Dry" arthroscopic assistance provides the surgeon with an enhanced view of the tumor and tumor cavity, minimizes invasiveness, and has the potential to reduce complications without compromising the completeness of the excision.

The Use of Anterior Superior Iliac Spine Osteotomy to Access the Anterior Column in Tumor Resection: A Case Report.

CASE: A 24-year-old woman with chondrosarcoma of the superior pubic ramus underwent a Type III pelvic resection through an ilioinguinal approach, modified with anterior superior iliac spine (ASIS) osteotomy. The osteotomy mobilized the ASIS and sartorious distally, exposing the anterior wall and superior ramus. A custom cutting guide was placed on the anterior acetabular wall for en bloc superior ramus resection with hip-sparing osteotomy and negative margins. CONCLUSION: ASIS osteotomy for sartorius mobilization improves visualization of the anterior column of the acetabulum and heals more reliably than sartorius tenotomy, therefore should be considered during tumor resection involving the anterior column, superior ramus, or acetabular wall.

Outcomes after antibiotic megaspacer implantation in patients with severe chronic periprosthetic infections.

Periprosthetic joint infection (PJI) is a rare postoperative complication that is treated with antibiotic spacers. Some patients develop severe, treatment-resistant, chronic PJI despite multiple attempts at salvaging the joint. Permanent resection of the joint or amputation may be the only definitive treatment. The purpose of this study is to describe the outcomes, infection resolution rate, and complications of two-stage revision, utilizing extensive resection of the affected bone and application of antibiotic megaspacers as a modality for limb-salvage. A review of 12 patients, initially referred for amputation due to chronically failed PJI, was conducted. All patients underwent extensive resection of the bone and surgical implantation of a custom-made antibiotic megaspacer between December 2016 and June 2019. Thirteen megaspacers were placed in 13 infected joints in 12 patients with a history of chronic PJI. Six patients (50%) had a diagnosis of osteomyelitis. Eradication of the infection leading to limb-salvage was successful in nine patients. Visual Analog Scale pain scores improved by 3.5, or 50%, after two-stage revision with megaprosthesis reimplantation (p = .008), and six patients (54.5%) had improvement in ambulation. Complication rates, not including reinfection or recurrence, following megaspacer and megaprosthesis reimplantation were 58.3% and 27.3%, respectively. One patient underwent amputation due to a life-threatening infection while two other patients underwent amputation due to debilitating complications following limb-salvage surgery. Statement of Clinical Significance: In patients whose PJI becomes treatment-resistant after multiple failed attempts at traditional two-stage exchange, performing extensive boney resection with placement of an antibiotic-laden megaspacer can be an effective method of achieving limb-salvage.

Hospital Resource Utilization Associated With Endoprosthetic Reconstruction Versus Primary Arthroplasty.

Endoprosthetic reconstructions of the hip and knee are currently reimbursed as primary hip and knee arthroplasty according to Current Procedural Terminology (CPT) coding guidelines. The purpose of this study was to compare hospital resources consumed by patients undergoing endoprosthetic reconstruction with those consumed by patients undergoing primary arthroplasty. The authors' hypothesis was that the former group carries more comorbidities, experiences longer length of stay (LOS), and has greater resource consumption. A retrospective review was performed of 61 patients undergoing endoprosthetic reconstruction and 745 patients undergoing primary hip or knee arthroplasty between 2015 and 2018 at a single institution. Demographic, clinical, and financial data were compared. The Charlson Comorbidity Index (CCI) was used to measure patients' health status and identify comorbidities associated with prolonged LOS through linear regression analysis. Patients who underwent endoprosthetic reconstruction had a greater than 3.5 times average LOS compared with primary arthroplasty patients: 10.81 days vs 2.94 days (P<.01). They demonstrated a higher mean CCI, higher rates of malignancy and pulmonary disease, and a wider age range. Their mean cost of care totaled $73,730.29, compared with $24,940.84 imposed by primary arthroplasty patients (P<.01). Significant predictors of LOS were malignancy status (metastatic or localized) and age younger than 50 years, with increased LOS being associated with increased cost. Patients undergoing endoprosthetic reconstruction of the hip and knee represent a fundamentally different patient population than primary arthroplasty patients based on comorbidities, variability in health status, and surgical indications. They have higher comorbidity scores and longer hospitalizations and consume more financial resources than primary arthroplasty patients. [Orthopedics. 2021;44(1):e73-e79.].

Team Approach: Rehabilitation Strategies for Patients After Osteosarcoma Reconstructive Surgery.

The multimodal treatment of osteosarcoma with chemotherapy, surgical resection, and reconstruction has improved outcomes after a limb-salvage surgical procedure. Physical rehabilitation considerations after surgical resection vary, depending on the location of the tumor. Physical medicine and rehabilitation physicians incorporate lymphedema specialists, orthotists, and prosthetists to help to improve limb function. Beyond physical rehabilitation, psychological or behavioral interventions and nutritional rehabilitation are necessary to maximize a patient's return to function.

Recurrent Adolescent Giant-Cell Tumor of the Scaphoid: Scaphoid Excision with Intracarpal Fusion after Failed Curettage and Bone Grafting.

We present a case of the giant-cell tumor of bone in the scaphoid of a 17-year-old female. Imaging revealed an expansile lytic lesion of her scaphoid, and the diagnosis was confirmed with open biopsy. She was treated with curettage and iliac crest bone graft, in an effort to spare reconstruction of her wrist. After one year, she developed increasing tightness and pain. Local recurrence was apparent on radiographs, and CT revealed increased lucency with bony destruction in the area of prior excision. She was successfully treated, without recurrence to date, with complete scaphoid excision and a four-corner wrist fusion. Local recurrence of the giant-cell tumor of bone is high, especially in carpal bones. When treating patients with advanced lesions, more aggressive initial options should be considered.

Should the Use of Biologic Agents in Patients With Renal and Lung Cancer Affect Our Surgical Management of Femoral Metastases?

BACKGROUND: Biologic agents may prolong survival of patients with certain kidney and lung adenocarcinomas that have metastasized to bone, and patient response to these agents should be considered when choosing between an endoprosthesis and internal fixation for surgical treatment of femoral metastases. QUESTIONS/PURPOSES: Among patients undergoing surgery for femoral metastases of lung or renal cell carcinoma, (1) Does survival differ between patients who receive only cytotoxic chemotherapy and those who either respond or do not respond to biologic therapy? (2) Does postsurgical incidence of local disease progression differ between groups stratified by systemic treatment and response? (3) Does implant survival differ among groups stratified by systemic treatment and response? METHODS: From our institutional longitudinally maintained orthopaedic database, patients were identified by a query initially identifying all patients who carried a diagnosis of renal cell carcinoma or lung carcinoma. Patients who underwent internal fixation or prosthetic reconstruction between 2000 and 2016 for pathologic fracture of the femur and who survived ≥ 1 year after surgery were studied. Patients who received either traditional cytotoxic chemotherapy or a biologic agent were included. Patients were classified as responders or nonresponders to biologic agents based on whether they had clinical and imaging evidence of a response recorded on two consecutive office visits over ≥ 6 months. Endpoints were overall survival from the time of diagnosis, survival after the femoral operation, evidence of disease progression in the femoral operative site, and symptomatic local disease progression for which revision surgery was necessary. Our analysis included 148 patients with renal (n = 26) and lung (n = 122) adenocarcinoma. Fifty-one patients received traditional chemotherapy only. Of 97 patients who received a biologic agent, 41 achieved a response (stabilization/regression of visceral metastases), whereas 56 developed disease progression. We analyzed overall patient survival with the Kaplan-Meier method and used the log-rank test to identify significant differences (p < 0.05) between groups. RESULTS: One-year survival after surgery among patients responsive to biologic therapy was 61% compared with 20% among patients nonresponsive to biologics (p < 0.001) and 10% among those who received chemotherapy only (p < 0.009). With the number of patients we had to study, we could not detect any difference in local progression of femoral disease associated with systemic treatment and response. Radiologic evidence of periimplant local disease progression developed in three (7%) of 41 patients who responded to biologic treatment, two (3%) of 56 patients nonresponsive to biologics, and one (2%) of 51 patients treated with traditional chemotherapy. With the numbers of patients we had, we could not detect a difference in patients who underwent revision. All three patients responsive to biologics who developed local recurrence underwent revision, whereas the two without a response to biologics did not. CONCLUSIONS: Biologic therapy improves the overall longevity of some patients with lung and renal metastases to the femur in whom a visceral disease response occurred. In our limited cohort, we could not demonstrate an implant survival difference between such patients and those with shorter survival who may have had more aggressive disease. However, an increased life expectancy beyond 1 year among patients responsive to biologics may increase risk of mechanical failure of fixation constructs. LEVEL OF EVIDENCE: Level III, therapeutic study.

Interosseous Ligament and Transverse Forearm Stability: A Biomechanical Cadaver Study.

PURPOSE: The interosseous ligament (IOL) is known to be an important longitudinal stabilizer of the forearm. We hypothesize that it may also contribute to transverse stability, with pronosupination tensioning of the radius relative to the ulna. Therefore, when injured, we predict the interosseous space should widen in the transverse plane, enough to be appreciable on plain radiographs. A measurable difference in interosseous space, comparing an injured with an uninjured forearm, can potentially be of diagnostic and clinical value. METHODS: Ten fresh-frozen cadaver arms (from 5 individuals) were radiographed in 6 different positions of forearm supination, first in an uninjured state and then with the IOL sectioned, both partially (central band only) and completely. The transverse interosseous distance was measured on radiographs using edge detection software and compared using analysis of variance and contrast analysis. The maximum range of pronosupination was also compared before and after injury, using a paired t test. RESULTS: Average maximum supination increased from 84° to 106°, and pronation from 69° to 84°, after the IOL was sectioned completely. Sectioning of the IOL led to a statistically significant increase in the interosseous distance, a minimum of 2 mm, in all but one forearm position. CONCLUSIONS: The IOL of the forearm plays an important role in providing transverse stability to the radius and ulna. When the IOL is sectioned, the forearm exhibits increased pronosupination range of motion. Radiographs of bilateral forearms taken in identical rotational position can reliably differentiate between an intact and torn IOL in cadavers. CLINICAL RELEVANCE: The IOL's stabilizing role during forearm rotation suggests a novel strategy for diagnosing forearm IOL injury using comparative radiographic measurements.

Management of Bone Sarcoma.

Treatment of bone sarcoma requires careful planning and involvement of an experienced multidisciplinary team. Significant advancements in systemic therapy, radiation, and surgery in recent years have contributed to improved functional and survival outcomes for patients with these difficult tumors, and emerging technologies hold promise for further advancement.

Protocol-Based Arthroplasty: Less Is More.

EDUCATIONAL OBJECTIVES: As a result of reading this article, physicians should be able to: 1. State an argument for, and background information on, patient-centered arthroplasty protocols. 2. Describe specific recommendations for designing a simplified arthroplasty care pathway that is reproducible in other institutions. 3. Discuss cost-effectiveness research on the latest value-delivering protocols. 4. Recognize areas of continued research and opportunities for future improvement in protocol development. Total joint arthroplasty is a successful orthopedic procedure that is performed in high volume in the United States and internationally. As economic pressures continue to mount in the US health care system, it will become increasingly important to minimize cost and improve quality and value. At the authors' institution, a protocol-based arthroplasty model is used, in many ways based on simplification of the patient care pathway. The largely evidence-based protocol has its foundation in eliminating unnecessary dogmatic practices, enhancing the patient experience, and achieving cost-effectiveness. The authors believe that a model like this can be applied to joint arthroplasty practices across the country in the future to maximize the value delivered to patients.

Comparison of crossed screw versus plate fixation for radial neck fractures.

BACKGROUND: Fixation of radial neck fractures can be achieved with a plate and screw construct or, in absence of comminution, with two obliquely-oriented screws. This study investigated the mechanical properties, specifically the stiffness and load to failure, of these two fixation strategies in a cadaver model. METHODS: Ten matched-pair radii were removed from fresh cadaver arms. A transverse osteotomy was created at the neck of each radius. Right-sided radii were fixed with two oblique headless compression screws; left-sided radii were fixed with a radial neck plate. The distal aspect of each radius was potted in urethane casting resin. The radial head was loaded in shear in 4 different planes (medial to lateral, lateral to medial, posterior to anterior, and anterior to posterior) using an Instron machine. Stiffness and load to failure were recorded. FINDINGS: The stiffness of both constructs was similar in all planes except for loading from medial to lateral where the screw construct was 1.8 times stiffer. Average ultimate failure occurred at 229N for the screws and 206N for the plate. Failure strength was not statistically different. However, mode of failure differed for both fixation constructs, the plate failed in bending while the screws failed by pullout and fracture. INTERPRETATION: The two strategies provide similar strength and stiffness for the fixation of transverse, non-comminuted radial neck fractures. While plate and screw constructs are more appropriate for axially unstable or comminuted fractures, two oblique screws might be preferred for simple transverse neck fractures since this strategy requires less exposure and the implant is buried.