Lateral femoral chondral lesions are more frequent when an anterior cruciate ligament tear is concomitant with a lateral femoral notch sign, but do not progress over time.

BACKGROUND: The lateral femoral notch sign (LFNS) is caused by an impact to the lateral femoral condyle during a pivot shift injury and affects 25% to 33% of patients with an anterior cruciate ligament (ACL) rupture. The primary aim of this study was to compare the incidence of chondral lesions 1year after ACL reconstruction, while taking into consideration preoperative chondral damage, in patients with and without a preoperative LFNS. The primary outcome measure was the presence of chondral lesions involving the lateral femoral condyle, confirmed on magnetic resonance imaging (MRI) using the Outerbridge classification, at 1year postoperative. The secondary outcome measures were bone bruise of the lateral femoral condyle confirmed on MRI, the International Knee Documentation Committee (IKDC), Lysholm and Tegner functional scores taken 1year after surgery. METHODS: Sixty patients were included-30 with preoperative LFNS and 30 without-in a retrospective, comparative study of prospectively collected data on patients operated between August 2018 and December 2020. RESULTS: A lateral femoral chondral lesion 1year after surgery was significantly more common in the group with a preoperative LFNS (37% [n=11] versus 13% [n=4] in the group without a preoperative LFNS, p=0.036). Adjusting the statistical analysis for preoperative body mass index (BMI) did not impact these results (adjusted odds ratio [OR]=3.83 [95%CI: 1.03-14.24]; p=0.045). Adjusting for a preoperative lateral femoral chondral lesion had an impact on these results (adjusted OR=0.78 [95%CI: 0.12-5.08]; p=0.793). This indicates that a preoperative LFNS is not significantly and independently associated with a lateral femoral chondral lesion at 1year postoperative when the analysis is adjusted for a preoperative lateral femoral chondral lesion. However, having a preoperative lateral femoral chondral lesion is significantly correlated with the presence of a lateral femoral chondral lesion 1year after the surgery (adjusted OR=63.31 [95%CI: 5.94-674.8]; p=0.001). There were no significant differences in terms of bone bruise on MRI (p=1.0), or for the IKDC (p=0.310), Lysholm (p=0.416) and Tegner (p=0.644) functional scores. The LFNS was still present in 21 out of 30 patients (70%) at 1year postoperative. The preoperative LFNS was significantly smaller in the group without a chondral lesion compared to the group with a chondral lesion 1year after the surgery (median=2.30mm [IQR: 1.40; 3.00] versus 3.10mm [IQR: 2.50; 3.40]; p value=0.045). CONCLUSIONS: Patients with a preoperative LFNS are three times more likely to have a chondral lesion in the notch region 1year after surgery. These chondral lesions are concomitant to the injury and do not progress over time. LEVEL OF EVIDENCE: III.

Pediatric cartilaginous lateral femoral condyle Hoffa fracture: a case report and review of the literature.

INTRODUCTION: Hoffa fractures are challenging coronally-oriented articular injuries of the femoral condyle. These fractures are rare in adults and extremely rare in the skeletally immature, with few cases reported in literature. To prevent mal- or non-union, Hoffa fractures require prompt surgical stabilisation with anatomic reduction and internal fixation. CASE REPORT: We discuss the case of a lateral distal femoral condyle cartilaginous Hoffa fracture in a ten-year-old male patient. The patient presented after a football non-contact "twist and pop" injury with radiographic imaging described as an osteochondritis dissecans lesion. An MRI was obtained which demonstrated a lateral distal femoral condyle osteochondral fracture. An operative plan was formulated to perform arthroscopic reduction and bio-compression screw fixation to minimize damage to the physis and surrounding tissues. Hyperflexion of the knee allowed for anatomic fracture reduction with the placement of 2 bio-compression screws serving as maintenance of fixation. The patient did well postoperatively and returned to full activity after 6 months. CONCLUSION: Hoffa fractures in the pediatric population are rare and can occur not only through bone but also through the thick chondral layer in younger patients. These are extremely difficult to diagnose through X-Ray alone. The prompt use of MRI imaging allows for operative fixation in a timely fashion, while an arthroscopic-only approach allows for minimal tissue damage. With an appropriate fracture type, hyper-flexion reduces and stabilizes the fracture, permitting the placement of minimally invasive bio-compression fixation.

Ipsilateral proximal and shaft femoral fractures: Results of two treatment strategies / Fracturas ipsilaterales proximales y diafisarias del fémur: resultados de 2 estrategias de tratamiento

Introduction: Ipsilateral proximal and shaft femoral fractures typically occur in young adults after high-energy trauma. No consensus exists regarding the optimal internal fixation device or surgical strategy for these complex fractures. Our main objective is to identify differences on outcomes and complications between patients treated with one or combined implants. Material and method: This is a single-center retrospective cohort study in patients with associated fractures of the proximal (31 AO) and shaft femur (32 AO). We divided the patients into two groups according to the use of single (Group I) or combined implants (Group II). Demographic, clinical, radiological, surgical data and development of complications were collected.Results: We identified 28 patients (19 men and 9 women) with an average age of 43 years. We used an anterograde femoral nail in group I (17 patients) and a retrograde femoral nail or a plate associated with hip lag screws or sliding hip screw in Group II (11 patients). Patients were followed up for 26.28 (9.12–62.88) months. Osteonecrosis of the femoral head, osteoarthritis, infection or nonunion was found in 9 patients (32%). No significant differences (p 0.70) were found in complications between two groups or between definitive surgical fixation before or after the first 24h. Conclusions: No differences in the development of complications or timing of definitive fixation were found between the use of one or combined implants in ipsilateral proximal femur and shaft fractures. Regardless of the implant chosen, an appropriate osteosynthesis technique is crucial, even so high complication rates are expected.

Introducción: Las fracturas ipsilaterales proximales y diafisarias del fémur suelen ocurrir en adultos jóvenes después de un traumatismo de alta energía. No existe consenso sobre el dispositivo de fijación interna óptimo o la estrategia quirúrgica para estas fracturas complejas. Nuestro principal objetivo es identificar las diferencias en los resultados y complicaciones entre los pacientes tratados con un implante o combinados. Material y método: Este es un estudio de cohorte retrospectivo unicéntrico en pacientes con fracturas asociadas del fémur proximal (31 AO) y diafisarias (32 AO). Dividimos a los pacientes en 2 grupos según el uso de implantes únicos (grupo i) o combinados (grupo ii). Se recogieron datos demográficos, clínicos, radiológicos, quirúrgicos y complicaciones. Resultados: Se identificaron 28 pacientes (19 hombres y 9 mujeres) con una edad promedio de 43 años. Utilizamos un clavo femoral anterógrado en el grupo i (17 pacientes) y un clavo femoral retrógrado o una placa con tornillos a compresión o tornillo deslizante de cadera en el grupo ii (11 pacientes). Los pacientes fueron seguidos durante 26,28 (9,12-62,88) meses. Se encontró osteonecrosis de la cabeza femoral, osteoartritis, infección o seudoartrosis en 9 pacientes (32%). No se encontraron diferencias significativas (p=0,70) en las complicaciones entre los 2 grupos o entre la fijación quirúrgica definitiva antes o después de las primeras 24h. Conclusiones: No se encontraron diferencias en el desarrollo de complicaciones o el momento de la fijación definitiva entre el uso de un implante o combinado en fracturas ipsilaterales de fémur proximal y diafisario. Independientemente del implante elegido, una técnica de osteosíntesis adecuada es crucial; aun así son esperables altas tasas de complicaciones.(AU)

[Artículo traducido] Fracturas ipsilaterales proximales y diafisarias del fémur: resultados de dos estrategias de tratamiento / Ipsilateral proximal and shaft femoral fractures: Results of two treatment strategies

Introduction: Ipsilateral proximal and shaft femoral fractures typically occur in young adults after high-energy trauma. No consensus exists regarding the optimal internal fixation device or surgical strategy for these complex fractures. Our main objective is to identify differences on outcomes and complications between patients treated with one or combined implants. Material and method: This is a single-center retrospective cohort study in patients with associated fractures of the proximal (31 AO) and shaft femur (32 AO). We divided the patients into two groups according to the use of single (Group I) or combined implants (Group II). Demographic, clinical, radiological, surgical data and development of complications were collected.Results: We identified 28 patients (19 men and 9 women) with an average age of 43 years. We used an anterograde femoral nail in group I (17 patients) and a retrograde femoral nail or a plate associated with hip lag screws or sliding hip screw in Group II (11 patients). Patients were followed up for 26.28 (9.12–62.88) months. Osteonecrosis of the femoral head, osteoarthritis, infection or nonunion was found in 9 patients (32%). No significant differences (p 0.70) were found in complications between two groups or between definitive surgical fixation before or after the first 24h. Conclusions: No differences in the development of complications or timing of definitive fixation were found between the use of one or combined implants in ipsilateral proximal femur and shaft fractures. Regardless of the implant chosen, an appropriate osteosynthesis technique is crucial, even so high complication rates are expected.

Introducción: Las fracturas ipsilaterales proximales y diafisarias del fémur suelen ocurrir en adultos jóvenes después de un traumatismo de alta energía. No existe consenso sobre el dispositivo de fijación interna óptimo o la estrategia quirúrgica para estas fracturas complejas. Nuestro principal objetivo es identificar las diferencias en los resultados y complicaciones entre los pacientes tratados con un implante o combinados. Material y método: Este es un estudio de cohorte retrospectivo unicéntrico en pacientes con fracturas asociadas del fémur proximal (31 AO) y diafisarias (32 AO). Dividimos a los pacientes en 2 grupos según el uso de implantes únicos (grupo i) o combinados (grupo ii). Se recogieron datos demográficos, clínicos, radiológicos, quirúrgicos y complicaciones. Resultados: Se identificaron 28 pacientes (19 hombres y 9 mujeres) con una edad promedio de 43 años. Utilizamos un clavo femoral anterógrado en el grupo i (17 pacientes) y un clavo femoral retrógrado o una placa con tornillos a compresión o tornillo deslizante de cadera en el grupo ii (11 pacientes). Los pacientes fueron seguidos durante 26,28 (9,12-62,88) meses. Se encontró osteonecrosis de la cabeza femoral, osteoartritis, infección o seudoartrosis en 9 pacientes (32%). No se encontraron diferencias significativas (p=0,70) en las complicaciones entre los 2 grupos o entre la fijación quirúrgica definitiva antes o después de las primeras 24h. Conclusiones: No se encontraron diferencias en el desarrollo de complicaciones o el momento de la fijación definitiva entre el uso de un implante o combinado en fracturas ipsilaterales de fémur proximal y diafisario. Independientemente del implante elegido, una técnica de osteosíntesis adecuada es crucial; aun así son esperables altas tasas de complicaciones.(AU)

Continuous improvement in optimizing the timing of axial, hip, and femoral fracture fixation.

Benefits of early stabilization of femoral shaft fractures, in mitigation of pulmonary and other complications, have been recognized over the past decades. Investigation into the appropriate level of resuscitation, and other measures of readiness for definitive fixation, versus a damage control strategy have been ongoing. These principles are now being applied to fractures of the thoracolumbar spine, pelvis, and acetabulum. Systems of trauma care are evolving to encompass attention to expeditious and safe management of not only multiply injured patients with these major fractures, but also definitive care for hip and periprosthetic fractures, which pose a similar burden of patient recumbency until stabilized. Future directions regarding refinement of patient resuscitation, assessment, and treatment are anticipated, as is the potential for data sharing and registries in enhancing trauma system functionality.

Antibiotic cement-coated rigid locked nails in infected femoral and tibial nonunion. Reoperation rates of commercial versus custom-made nails.

INTRODUCTION: The objective of this study is to assess bone union, infection control, and reoperation rates in a series of patients with infected femoral or tibial nonunion treated with antibiotic-cement-coated rigid nails and to compare the results obtained with custom-made nails versus commercial nails. METHODS: We retrospectively analyzed a series of consecutive patients with infected nonunion of the femur or the tibia treated with antibiotic-cement-coated rigid nails between January 2010 and 2020. We assessed patients' distinctive characteristics, initial injury, type of nail used (custom-made nail with vancomycin or commercial nail with gentamicin), success rate (bone union + infection control), reoperation rate, and failure rate. Comparative analyses were conducted between reoperated and non-reoperated patients regarding the type of nail used. A multivariate regression analysis was performed to assess the risk variables that impacted reoperation rates. RESULTS: We included 54 patients with 22 (40.74%) infected femoral nonunions and 32 (59.25%) tibial nonunions, who were treated with 38 (70.37%) custom-made antibiotic-cement coated nails and 16 (29.62%) commercial nails. Bone union and infection control were achieved in 51 (94.44%) cases. The reoperation rate was 40.74% (n = 22), and the failure rate was 5.55% (n = 3). The use of custom-made nails was associated with a higher risk of reoperation (Odds Ratio 4.71; 95% Confidence Interval 1.10 - 20.17; p = 0.036). CONCLUSION: Antibiotic-cement-coated nails reached a 94.44% success rate. Nails manufactured in the OR coated with vancomycin cement were associated with a higher risk of reoperation than commercial nails loaded with gentamicin cement. LEVEL OF EVIDENCE: III comparative, observational, non-randomized.

Novel Approach of Femur Shortening With Insertion of Expandable Rod to Achieve End-to-End Repair of Sciatic Nerve Laceration.

BACKGROUND: Sciatic nerve injuries are challenging for diagnosis and treatment. Particularly in proximally located high-grade injuries, neurorrhaphy often has poor outcomes. Most advocate autologous grafting and some more recently have suggested the value of knee flexion braces to facilitate end-to-end repair. OBJECTIVE: To describe a case of femur shortening to facilitate tension-free, end-to-end sciatic nerve neurorrhaphy. METHODS: The patient was a 17-year-old man who was injured by the propeller of a motor boat and suffered a series of lacerations to both lower extremities including transection of his right sciatic nerve in the proximal thigh. After extensive mobilization of the nerve, a greater than 7-cm gap was still present. The patient was treated with femur shortening to facilitate end-to-end coaptation. He subsequently had an expandable rod placed which was lengthened 1 mm per day until his leg length was symmetric. RESULTS: Within 7 months postoperatively, the patient had an advancing Tinel sign and paresthesias to the dorsum of his foot. Nine months postoperatively, he had early mobility in his plantarflexion. CONCLUSION: We present a novel method of femur shortening with insertion of an expandable rod to facilitate direct end-to-end and tension-free sciatic nerve neurorrhaphy in a proximally located injury. Furthermore, larger scale and comparative studies are warranted to further explore this and other techniques.

Establishing a Diaphyseal Femur Fracture Model in Mice.

Bones have a significant regenerative capacity. However, fracture healing is a complex process, and depending on the severity of the lesions and the age and overall health status of the patient, failures can occur, leading to delayed union or nonunion. Due to the increasing number of fractures resulting from high-energy trauma and aging, the development of innovative therapeutic strategies to improve bone repair based on the combination of skeletal/mesenchymal stem/stromal cells and biomimetic biomaterials is urgently needed. To this end, the use of reliable animal models is fundamental to better understanding the key cellular and molecular mechanisms that determine the healing outcomes. Of all the models, the mouse is the preferred research model because it offers a wide variety of transgenic strains and reagents for experimental analysis. However, the establishment of fractures in mice may be technically challenging due to their small size. Therefore, this article aims to demonstrate the procedures for the surgical establishment of a diaphyseal femur fracture in mice, which is stabilized with an intramedullary wire and resembles the most common bone repair process, through cartilaginous callus formation.

Treatment of osteochondral fracture of lateral femoral condyle after patella dislocation with anchor absorbable sutures: A new surgical technique and a case report.

RATIONALE: Osteochondral fracture (OCF) in weight-bearing area of lateral femoral condyle (LFC) is a rare combined injury caused by patellar dislocation. PATIENT CONCERNS: A 15-year-old female student accidentally sprained her right knee while participating in sports activities. The patient felt pain in his right knee and limited movement. After hospitalization, the patients underwent computed tomography scan and magnetic resonance examination. DIAGNOSIS: According to the imaging results, patellar dislocation combined with OCF of LFC was considered in diagnosis. INTERVENTIONS: Through the lateral parapatellar approach, we reduced the osteochondral mass and bundled it with absorbable sutures of anchors. OUTCOMES: The functional and radiographic outcome were satisfactory at 18 months after operation. LESSONS: Anchor absorbable suture bridge fixation for this kind of OCF is not only effective, but also economical.

Fixation of the neglected subcutaneous osteochondral fragment of large medial femoral condyle defect in adult male: A case report.

Knee osteochondral fractures are among the most common orthopaedic injuries, and their diagnosis and treatment is always open to debate among orthopaedic surgeons. In this case report, we described the surgical treatment and 2 years of follow-up of an adult male patient who underwent delayed osteochondral fixation with an iliac graft. A medial parapatellar incision was made to perform open reduction and internal fixation. The fracture surface at the medial condyle of the femur was debrided with a curette, followed by placement of the tricortical graft harvested from the iliac crest into the defect at the medial femoral condyle. The osteochondral fragment was then placed on top and was fixed with three headless compression screws together with the iliac crest graft for joint surface restoration. While the patient's preoperative knee injury and osteoarthritis outcome score (KOOS) was 38 and it increased to 74 during two years follow-up. Despite the scarcity of information on delayed fixation of osteochondral fractures, osteochondral fragments with preserved viability should be fixed, regardless of the timing, as suggested by the successful outcomes obtained in this study.

Síndrome de embolismo graso en fractura de huesos largos, reporte de caso / Fat embolism syndrome in long bone fractures, case report

Introducción: El síndrome de embolismo graso es una complicación severa, aun-que poco frecuente de trauma grave. Es desencadenado por el paso de partículas de grasa hacia la microcirculación en varios órganos. La tríada característica: lesión pulmonar, hemorragia petequial y disfunción neurológica. Su prevalencia varía se-gún los criterios diagnósticos y la causa desencadenante, dificultando su detección temprana. Presentación del caso: Caso 1. Paciente 22 años, masculino, sufrió accidente automovilístico con fracturas abierta de fémur, tibia y peroné derechos, resueltas quirúrgicamente, a las 5 horas del evento sufre deterioro respiratorio, petequias conjuntivales, torácicas y en extremidades; posteriormente deterioro de concien-cia, estatus epiléptico y síndrome de hiperactividad simpática paroxística. Caso 2. Paciente 29 años, masculino, sufrió volcamiento del vehículo en el que viajaba, sufriendo fracturas cerradas de tibia, peroné y fémur izquierdas, luego de la cirugía traumatológica sufrió deterioro del estado de conciencia, petequias conjuntivales e hipoxemia.Diagnósticos e intervenciones: los dos pacientes fueron operados para resolución traumatológica dentro de las primeras 24 horas, luego del aparecimiento de síntomas neurológicos se sometieron a neuroimagen encontrándose el patrón de "campo de es-trellas" y recibieron corticoides.Resultados: Caso 1 el desenlace fue estado vegetativo, Caso 2 recuperación completa.Conclusión: La detección es imprescindible para establecer el tratamiento temprano, planificar la cirugía traumatológica o diferirla y estimar el pronóstico según la evolu-ción. El síndrome de embolia grasa cerebral es una causa rara del síndrome de hipe-ractividad simpática paroxística

Introduction: Fat embolism syndrome is a severe, although rare complication of major trauma. It is triggered by the passage of fat particles into the microcirculation in various organs. The characteristic triad: lung injury, petechial hemorrhage and neurological dysfunction. Its prevalence varies according to the diagnostic criteria and the triggering cause, making its early detection difficult. Case presentation: Case 1. Patient 22 years old, male, suffered a car accident with open fracture of the right femur, tibia and fibula, surgically resolved, 5 hours after the event he suffered respiratory impairment, conjunctival, thoracic and extre-mity petechiae; later impaired consciousness, status epilepticus and paroxysmal sympathetic hyperactivity syndrome. Case 2. Patient 29 years old, male, suffered overturning of the vehicle in which he was traveling, suffering closed fractures of the left tibia, fibula and femur, after trauma surgery he suffered impaired consciousness, conjunctival petechiae and hypoxemia.Diagnoses and interventions: Both patients underwent surgery for trauma reso-lution within 24 hours, after the appearance of neurological symptoms they un-derwent neuroimaging finding "star field" pattern, both received corticosteroids.Results: Case 1 the outcome was vegetative state, Case 2 complete recovery.Conclusion: Detection is essential to establish early treatment, to plan trauma sur-gery or to defer it and to estimate prognosis according to evolution. Cerebral fat em-bolism syndrome is a rare cause of paroxysmal sympathetic hyperactivity syndrome.

Prevalence of inflicted and neglectful femur shaft fractures in young children in national level I trauma centers.

BACKGROUND: The prevalence of inflicted femur fractures in young children varies (1.5-35.2%), but these data are based on small retrospective studies with high heterogeneity. Age and mobility of the child seem to be indicators of inflicted trauma. OBJECTIVE: This study describes other factors associated with inflicted and neglectful trauma that can be used to distinguish inflicted and neglectful from accidental femur fractures. MATERIALS AND METHODS: This retrospective study included children (0-6 years) who presented with an isolated femur fracture at 1 of the 11 level I trauma centers in the Netherlands between January 2010 and January 2016. Outcomes were classified based on the conclusions of the Child Abuse and Neglect teams or the court. Cases in which conclusions were unavailable and there was no clear accidental cause were reviewed by an expert panel. RESULTS: The study included 328 children; 295 (89.9%) cases were classified as accidental trauma. Inflicted trauma was found in 14 (4.3%), while 19 (5.8%) were cases of neglect. Indicators of inflicted trauma were age 0-5 months (29%, positive likelihood ratio [LR +] 8.35), 6-12 months (18%, LR + 5.98) and 18-23 months (14%, LR + 3.74). Indicators of neglect were age 6-11 months (18%, LR + 4.41) and age 18-23 months (8%, LR + 1.65). There was no difference in fracture morphology among groups. CONCLUSION: It is unlikely that an isolated femur fracture in ambulatory children age > 24 months is caused by inflicted trauma/neglect. Caution is advised in children younger than 24 months because that age is the main factor associated with inflicted trauma/neglect and inflicted femur fractures.

[A sudden onset of groin pain]. / Plotselinge pijn in de lies.

We describe an 11-year-old boy with sudden onset of right groin pain which occurred during soccer. He was diagnosed with an avulsion fracture of the lesser trochanter, a hyperextension and rotation trauma due to traction on the iliopsoas tendon. The treatment was conservative and full function returned.

Síndrome de pinzamiento isquiofemoral: reporte de un caso inusual / Ischiofemoral impingement syndrome: Report of an unusual case

El síndrome de pinzamiento isquiofemoral suele ser una patología infradiagnosticada que forma parte de uno de los diagnósticos diferenciales a tener en cuenta en el dolor de cadera. Inicialmente fue descrito con procedimientos quirúrgicos, pero con el paso del tiempo se han ido describiendo diferentes entidades médicas, así como técnicas y posturas mantenidas, que puede agravar el cuadro, pudiendo asociar incluso afectación neurológica. En la actualidad el tratamiento es inicialmente conservador con medidas de reposo, analgesia, frío e inicio progresivo de ejercicios dirigidos a la musculatura lumbar, glútea y de miembros inferiores, pero no existe un protocolo de actuación establecido unificado.(AU)

Ischiofemoral impingement syndrome is usually underdiagnosed; this syndrome forms part of the differential diagnoses to be included in hip pain. It was initially described with surgical procedures but, with the passage of time, various medical entities have been described, as well as techniques and postures that can aggravate this syndrome, which can even be associated with neurological involvement. Current treatment is initially conservative, consisting of rest, analgesia, cold and progressive exercises aimed at the lumber and gluteal muscles and lower extremities but there is no established standard of care.(AU)

Role of Macrophages and Plasminogen Activator Inhibitor-1 in Delayed Bone Repair Induced by Glucocorticoids in Mice.

Glucocorticoids delay fracture healing and induce osteoporosis. However, the mechanisms by which glucocorticoids delay bone repair have yet to be clarified. Plasminogen activator inhibitor-1 (PAI-1) is the principal inhibitor of plasminogen activators and an adipocytokine that regulates metabolism. We herein investigated the roles of macrophages in glucocorticoid-induced delays in bone repair after femoral bone injury using PAI-1-deficient female mice intraperitoneally administered with dexamethasone (Dex). Dex significantly decreased the number of F4/80-positive macrophages at the damaged site two days after femoral bone injury. It also attenuated bone injury-induced decreases in the number of hematopoietic stem cells in bone marrow in wild-type and PAI-1-deficient mice. PAI-1 deficiency significantly weakened Dex-induced decreases in macrophage number and macrophage colony-stimulating factor (M-CSF) mRNA levels at the damaged site two days after bone injury. It also significantly ameliorated the Dex-induced inhibition of macrophage phagocytosis at the damaged site. In conclusion, we herein demonstrated that Dex decreased the number of macrophages at the damaged site during early bone repair after femoral bone injury partly through PAI-1 and M-CSF in mice.

New tip-apex distance and calcar-referenced tip-apex distance cut-offs may be the best predictors for cut-out risk after intramedullary fixation of proximal femur fractures.

Cut-out is one of the most common mechanical failures in the internal fixation of trochanteric hip fractures. The tip-apex distance (TAD), and the calcar-referenced tip apex distance (CalTAD) are the radiographic parameters that most predict the risk of cut-out. The optimal CalTAD value has not yet been defined, but the optimal TAD value is reported as 25 mm or less. However, this cut-off is highly specific but poorly sensitive. The aim of this study was to determine highly specific and sensitive TAD and CalTAD values and shed light on the role of other clinical variables. A total of 604 patients were included in this retrospective cross-sectional study. For each patient the following data were recorded: number of cut-out, AO/OTA classification, quality of the reduction, type of nail, cervicodiaphyseal angle, type of distal locking, post-operative weight-bearing, TAD and CalTAD values, and the position of the screw head in the femoral head according to the Cleveland system. The incidence of cut-out across the sample was 3.1%. The median TAD in the cut-out group was 38.72, while in the no cut-out group it was 22.16. The median CalTAD in the cut-out group was 39.34, while in the no cut-out group it was 22.19. The cut-off values for TAD and CalTAD with highest value of sensitivity and specificity for the risk of cut-out were 34.8 and 35.2, respectively. The incidence of cut-out can be reduced by performing careful minimal reduction and ensuring stable fixation by avoiding TAD > 34.8 mm and CalTAD > 35.2 mm.

Reconstruction of Massive Segmental Distal Femoral Metaphyseal Bone Defects After Open Injury: A Study of 20 Patients Managed with Intercalary Gamma-Irradiated Structural Allografts and Autologous Cancellous Grafts.

BACKGROUND: Our aim was to examine the outcome of gamma-irradiated intercalary structural allografts combined with autologous cancellous grafts in treating large metaphyseal bone defects of the distal femur following open injuries. METHODS: We prospectively included 20 consecutive patients with large metaphyseal bone defects of >4 cm located in the region of the distal femur following open injuries treated between 2010 and 2018, with a mean follow-up of 2 years (range, 2 to 10 years). Of these patients,18 were men and 2 were women. The mean age was 39 years (range, 22 to 72 years). The mean length of the bone defects was 10.1 cm (range, 5.5 to 14.5 cm), and all were in the metaphysis of the distal femur. The surgical technique included initial early debridement and external fixation followed by reconstruction of the bone defect using structural allograft combined with autologous cancellous bone graft harvested from the iliac crest and locking plate fixation. Definitive fixation was performed at an average period of 22.5 days (range, 3 to 84 days) after injury. Osseous union, rate of infection, complications, need for secondary procedures, and functional outcome using the Lower Extremity Functional Scale (LEFS) at the final follow-up were assessed. RESULTS: After excluding 1 patient who was lost to follow-up, 19 patients with complete follow-up were available for analysis. Of those, 13 patients (68%) achieved complete union at both ends of the allograft with host bone without any further intervention. Three patients (16%) developed aseptic nonunion of the proximal end of the allograft requiring 1 additional procedure each to achieve union. Four patients (21%) developed a deep surgical site infection. Of those, 1 elderly patient required above-the-knee amputation following uncontrolled diabetes and infection. A second patient required 2 additional procedures, and a third patient needed 4 additional procedures to achieve union. The fourth patient developed infection after achieving union, and the infection subsided after debridement and implant removal. The mean LEFS score for all 19 patients was 55 (range, 41 to 75). CONCLUSIONS: Use of allograft was a reasonable single-stage alternative solution for massive distal femoral bone defects, which united without additional surgery in two-thirds of the patients and without limb-length discrepancy. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Cadera flotante: análisis comparativo de resultados y lesiones asociadas / Floating hip: comparative analysis of outcomes and associated injuries

Objetivo: Describir los tiempos de internación, cirugía y rehabilitación de una serie de pacientes con cadera flotante. El objetivo secundario fue comparar los resultados obtenidos en función de la reinserción laboral con los de pacientes que sufrieron fracturas de pelvis o acetábulo sin fractura femoral asociada. Materiales y Métodos: Estudio descriptivo, retrospectivo y multicéntrico de pacientes con trauma de pelvis y acetábulo de alta energía, divididos en dos grupos de estudio según la presencia de fractura de fémur asociada homolateral (cadera flotante) para su comparación, durante el período comprendido entre enero de 2014 y marzo de 2019. Resultados: Se incluyó a 102 pacientes con trauma de pelvis o acetábulo agrupados en 2 poblaciones según la presencia de cadera flotante (cadera flotante 23; pelvis/acetábulo 79). Las medianas de días de internación [cadera flotante 15,5 (rango 4-193); pelvis/acetábulo 7 (rango 3-31); p = 0,0001] y de la cantidad de cirugías por paciente [cadera flotante 5 (rango 3-8); pelvis/acetábulo 2 (rango 1-4); p = 0,0001] fueron mayores en los pacientes con cadera flotante. Además, la incapacidad laboral temporaria fue más alta (p = 0,00012), sin diferencias significativas en la tasa de recalificación laboral (p = 0,11). Conclusión: La asociación de la lesión cadera flotante aumentó significativamente el tiempo de internación, los procedimientos quirúrgicos necesarios y el tiempo de recuperación según la incapacidad laboral temporaria en pacientes con trauma de pelvis o acetábulo. Nivel de Evidencia: III

Objective: We aim to describe the lengths of hospitalization, surgery, and rehabilitation of a series of patients with floating hip. As a secondary objective, to compare the outcomes obtained in terms of return to work in patients who had suffered fractures of the pelvis or acetabulum without an associated femoral fracture. Materials and Methods: Descriptive, retrospective, and multicenter study of patients with high-energy trauma to the pelvis and acetabulum divided into two study populations according to the presence of associated ipsilateral femur fracture (floating hip) for comparison, during the period January 2014 - March 2019. Results: 102 patients with pelvis and/or acetabulum trauma were included, grouped into 2 populations according to the presence of a float-ing hip (Floating hip: 23 patients; Pelvis/acetabulum: 79 patients). The median days of hospitalization [floating hip: median = 15.5 (range = 4-193); pelvis/acetabulum: 7 (3-31); p = 0.0001] and the number of surgeries per patient [FH: median = 5 (range = 3-8); pelvis/acetabulum: 2 (1-4); p = 0.0001] were higher in patients with floating hip. Additionally, temporary work disability was higher (p = 0.00012), with no significant differences in the rate of job retraining (p = 0.11). Conclusion: Floating hip significantly increased the length of hospitalization, necessary surgical procedures, and recovery times according to temporary work disability in patients with trauma to the pelvis and/or acetabulum. Level of Evidence: III

Heated Tobacco Products Impair Cell Viability, Osteoblastic Differentiation, and Bone Fracture-Healing.

BACKGROUND: The negative impact of cigarette smoking on bone union has been well documented. However, the impact of heated tobacco product (HTP) use on bone fracture-healing remains unclear. The present study investigated the effect of HTPs on preosteoblast viability, osteoblastic differentiation, and fracture-healing and compared the effects with those of conventional combustible cigarettes. METHODS: Cigarette smoke extracts (CSEs) were generated from combustible cigarettes (cCSE) and HTPs (hCSE). CSE concentrations were standardized by assessing optical density. Preosteoblast (MC3T3-E1) cells were incubated with normal medium, cCSE, or hCSE. The cell viability was assessed via MTT assay. After osteoblastic differentiation of CSE-exposed cells, alkaline phosphatase (ALP) activity was assessed. To assess the in vivo effects of CSEs, a femoral midshaft osteotomy was performed in a rat model; thereafter, saline solution, cCSE, or hCSE was injected intraperitoneally, and bone union was assessed on the basis of micro-computed tomography (µCT) and biomechanical analysis 4 weeks later. RESULTS: MC3T3-E1 cell viability was reduced in a time and concentration-dependent manner when treated with either cCSE or hCSE. ALP activity after osteoblastic differentiation of cCSE-treated cells was significantly lower than that of both untreated and hCSE-treated cells (mean and standard deviation, 452.4 ± 48.8 [untreated], 326.2 ± 26.2 [cCSE-treated], and 389.9 ± 26.6 [hCSE-treated] mol/L/min; p = 0.002). Moreover, the levels of osteoblastic differentiation in untreated and hCSE-treated cells differed significantly (p < 0.05). In vivo assessment of the femoral midshaft cortical region revealed that both cCSE and hCSE administration significantly decreased bone mineral content 4 weeks after surgery compared with levels observed in untreated animals (107.0 ± 11.9 [untreated], 94.5 ± 13.0 [cCSE-treated], and 89.0 ± 10.1 mg/cm3 [hCSE-treated]; p = 0.049). Additionally, cCSE and hCSE-exposed femora had significantly lower bone volumes than unexposed femora. Biomechanical analyses showed that both cCSE and hCSE administration significantly decreased femoral maximum load and elastic modulus (p = 0.015 and 0.019). CONCLUSIONS: HTP use impairs cell viability, osteoblastic differentiation, and bone fracture-healing at levels comparable with those associated with combustible cigarette use. CLINICAL RELEVANCE: HTP use negatively affects bone fracture-healing to a degree similar to that of combustible cigarettes. Orthopaedic surgeons should recommend HTP smoking cessation to improve bone union.

The influence of M-CSF on fracture healing in a mouse model.

Macrophage colony-stimulating factor 1 (M-CSF) is known to play a critical role during fracture repair e.g. by recruiting stem cells to the fracture site and impacting hard callus formation by stimulating osteoclastogenesis. The aim of this experiment was to study the impact of systemic M-CSF application and its effect on bony healing in a mouse model of femoral osteotomy. Doing so, we studied 61 wild type (wt) mice (18-week-old female C57BL/6) which were divided into three groups: (1) femoral osteotomy, (2) femoral osteotomy + stabilization with external fixator and (3) femoral osteotomy + stabilization with external fixator + systemic M-CSF application. Further, 12 op/op mice underwent femoral osteotomy and served as proof of concept. After being sacrificed at 28 days bony bridging was evaluated ex vivo with µCT, histological and biomechanical testing. Systemic M-CSF application impacted osteoclasts numbers, which were almost as low as found in op/op mice. Regarding callus size, the application of M-CSF in wt mice resulted in significantly larger calluses compared to wt mice without systemic M-CSF treatment. We further observed an anabolic effect of M-CSF application resulting in increased trabecular thickness compared to wt animals without additional M-CSF application. Systemic M-CSF application did not alter biomechanical properties in WT mice. The impact of M-CSF application in a mouse model of femoral osteotomy was oppositional to what we were expecting. While M-CSF application had a distinct anabolic effect on callus size as well as trabecular thickness, this on bottom line did not improve biomechanical properties. We hypothesize that in addition to the well-recognized negative effects of M-CSF on osteoclast numbers this seems to further downstream cause a lack of feedback on osteoblasts. Ultimately, continuous M-CSF application in the absence of co-stimulatory signals (e.g. RANKL) might overstimulate the hematopoietic linage in favor of tissue macrophages instead of osteoclasts.