An intramuscular hemangioma is a benign vascular tumor that often occurs in the lower extremities. We herein report a rare case of an intramuscular hemangioma that occurred in the gluteus medius muscle and was misdiagnosed as lumbar disc herniation. A 36-year-old woman presented with incidental and infrequent pain of the left buttock. She was diagnosed with lumbar disc herniation and underwent treatment. Although her pain was slightly relieved, relapse soon occurred. X-ray examination and magnetic resonance imaging revealed a mass in the gluteus medius muscle. The mass was suspected to be a malignant tumor and was therefore resected. The final diagnosis was an intramuscular hemangioma. Her pain completely disappeared thereafter and did not recur. Patients with intramuscular hemangiomas usually have no specific symptoms; therefore, this tumor is often misdiagnosed. When a satisfactory treatment effect is not obtained, the diagnosis should be reassessed in a timely manner.

Anterior cruciate ligament (ACL) is a primary stabilizer of the knee and constrains joint motion, and its injury is very common in clinic. There are many studies on the risk factors of ACL injury such as the ACL diameter, intercondylar notch width index (NWI), sagittal condylar shape, tibial posterior slope, tibia eminence size and so on. Large amount of research data has confirmed that all above are closely related to ACL injury. Among them the morphological characteristics of femoral condyle and tibial plateau are closely related to ACL injury. For example the tibial eminence, which is the hot topic of recent research. Whether or how does it relate to ACL injury has draw much interest of researchers. Since the tibial eminence and the ACL are both located in the intercondylar notch and adjacent to each other, we hypothesize the size of the tibial eminence may relate to the rupture of ACL. For there is report have found that reduced medial tibial eminence was associated with ACL injury, we suggest a hypothesis that enlarged tibia eminence may be a protective factor of ACL.

The posterior cruciate ligament (PCL) plays a crucial role for the posterior stability of the knee joint, accounting for 3% to 38% of acute knee injuries and frequently co‐occurring with other ligament injuries. PCL tibial avulsion fractures are not rare in clinical practice. Arthroscopic treatment for PCL tibial avulsion fractures has gained acceptance due to its ability to achieve anatomic reduction, restore ligament tension, and improve joint stability while minimizing surgical trauma and facilitating rapid recovery. However, the choice of fixation method remains a topic of ongoing debate. We employed a “Y”‐shaped suture technique combined with suspension fixation in the arthroscopic treatment of PCL tibial avulsion fractures. This technique effectively stabilizes the fracture while restoring PCL tension, resulting in improved recovery of knee stability and function. Technique Video: video See video under supplementary data.

Background: Sacroiliac joint infection is uncommon in clinical. It's initial symptoms are usually nonspecific, often confused with tuberculosis, septic arthritis of the hip, osteitis of the ilium and lumbar disc herniation which make it difficult to early diagnosis. There is few report about the sacroiliac joint infection, especially with multiple huge abscesses.Case presentation: A 29 years old male who developed pain of the right buttock, and firstly was diagnosed as lumbar disc herniation, then sacroiliac joint tuberculosis. The therapeutic effect was not satisfactory. We performed surgical debridement for him and get the clear diagnosis which is staphylococcus aureus infection of sacroiliac joint. After thoroughly debrided, the symptoms disappeared with adequate and regular antibiotic therapy.Conclusions: For sacroiliac joint infection, clinical suspicion is low, the condition is uncommon, and the general incidence is unknown. It's presentation is diverse. So when encountered similar situations, the sacroiliac joint infection should be considered, and the pathogen should be identified, in order to treat it correctly as soon as possible.

Background: Intramuscular hemangioma is a kind of benign vascular tumors often occurs in the lower extremity, which occurs in the gluteus medius muscle, and was misdiagnosed as lumbar disc herniation is rarely reported.Case presentation: A 36-year-old female who complaint of accidental pain of the left buttock. She was diagnosed as lumbar disc herniation, and accept the treatment. The symptom slightly relieved, but will relapse soon. Until she takes the X-ray and MRI, a mass was found in the gluteus medius muscle, which was suspected of malignant tumor. Then the tumor was resected and the final diagnosis is intramuscular hemangioma. The symptoms disappear completely and not recurrent.Conclusion: There are usually no special symptoms in patients with intramuscular hemangioma, so it is often misdiagnosed, when the treatment effect is not satisfied, the cause should be timely and correctly analyzed.