8Background: Lateral meniscal posterior root tears (LMPRT) result in loss of hoop forces 9 and significant increases in tibiofemoral contact pressures. Pre-operative imaging lacks 10 reliability and therefore holding an appropriate index of suspicion, based on the 11 epidemiology and risk factors for LMPRT, may reduce the rate of missed diagnoses. 12 Hypothesis/Purpose: The primary objectives of this study were to evaluate the incidence 13 and risk factors for lateral meniscus root lesions in a large series of patients undergoing 14 anterior cruciate ligament (ACL) reconstruction. 15 Study Design: Case series 16Methods: All patients who underwent primary or revision ACL reconstruction, between 17 January 2011 to April 2018 were considered for study eligibility. From this overall 18 population, all patients who underwent repair of a lateral meniscus posterior root tear 19 (LMPRT) were identified. The epidemiology of LMPRT was defined by the incidence 20 within the study population, stratified by key demographic parameters. Potentially 21 important risk factors for the presence of LMPRT were evaluated in multivariate logistic 22 regression analysis. 23Results: 3956 patients undergoing ACL reconstruction were included in the study. A 24LMPRT was identified and repaired in 262 patients (6.6%). Multivariate analyses 25 demonstrated that significant risk factors for LMPRT included a contact sports injury 26 mechanism (7.8% incidence with contact sports mechanism vs 4.5% with non-contact 27 mechanism 4.5%; OR = 1.69, IC95% 1.266 -2.285; P <.001) and the presence of a medial 28 meniscal tear (7.9% incidence with medial meniscal tear vs 5.8% in those without; OR = 29 1.532, IC95% 1.185 -1.979; P <.001). Although the incidence of LMPRT in male patients 30 (7.3%) was higher than females (4.8%) this was not significant in multivariate analysis (P 31 = 0.270). Patient age, revision ACL reconstruction and a pre-operative side to side laxity 32 difference of ≥ 6mm were not found to be significant risk factors for LMPRT. 33 Conclusion: The incidence of LMPRT was 6.6% in a large series of patients undergoing 34 ACL reconstruction. Participation in contact sports and the presence of a concomitant 35 medial meniscal tear were demonstrated to be important independent risk factors. Their 36 presence should raise the index of suspicion of this injury pattern. 37 38What is known about the subject: Previous reports on the epidemiology and risk factors 40 for LMPRT have all been limited by small study populations. This is an important 41 limitation because it reduces the confidence that can be held in the estimation of the true 42 incidence of these injuries. Understanding the epidemiology and risk factors for LMPRT 43 is of paramount importance because it is recognized that these injuries are likely to be 44 frequently missed and that left untreated can result in significant increases in tibiofemoral 45 compartment pressures and early arthritis. The recognized rate of missed diagnoses is due 46 to a lack of reliability of pre-operative ...

Complex dorsal metacarpophalangeal (MCP) joint dislocations as a result of hyperextension injuries are uncommon in the pediatric population and irreducible to closed maneuvers. Treatment of these complex lesions is invariably surgical, and dorsal or volar approaches are traditionally used. The authors describe a case of a 16-year-old male who suffered a fall onto his outstretched right hand in a soccer game. The patient presented to the ER with pain and deformity of the index finger MCP joint. Radiographs confirmed a complex MCP dislocation with a small osteochondral fragment. A lateral surgical approach was made, and interposition of the volar plate and an osteochondral fragment blocking the reduction were found. This versatile approach allowed access to volar and dorsal structures, minimizing the risk of surgical scarring and mobility arch limitation. To our knowledge, there are no reported cases regarding a lateral surgical approach.

This is a case report of pyogenic sacroiliitis in a pediatric patient caused by Streptococcus intermedius. The patient is a 16-year-old boy who presented to an emergency department with sudden onset of back pain radiating to the left lower extremity. The diagnosis was confounded by the presence of isthmic spondylolisthesis. Plain radiography demonstrated mild isthmic spondylolisthesis but no radiographic signs of tumor, trauma, infection, arthritis, or other developmental problems. The C-reactive protein level was 23 mg/L. Over the next 24 hours, the patient developed fever, and the C-reactive protein level increased to 233 mg/L. Sacroiliitis and an iliopsoas abscess were identified on MRI. Blood cultures grew S intermedius. The patient responded to antibiotic treatment and needle aspiration under CT guidance. Sacroiliitis is an uncommon condition and, to our knowledge, there is only one other case report of its being caused by S intermedius. The previous report was in an adult.