Introduction Calcium is an important coagulation factor and hypocalcemia is related to progression and poor prognosis of many cardiopulmonary diseases. However, influence of hypocalcemia on pulmonary thromboembolism (PTE) prognosis has never been reported. This study aimed to explore its prognostic value and optimize the pulmonary embolism severity index (PESI), the widely used prognosis assessment model, based on the value. Methods PTE patients’ variables in PESI and other related clinical characteristics including admission serum calcium were collected. Associations between these variables and PTE mortality were assessed by logistic regression and cox analysis. Variables significantly associated with 30-day PTE mortality were included to develop a new prognosis prediction rule and then its validity was compared with PESI and simplified PESI (sPESI). Results 496 PTE patients were included and 49.48% patients had hypocalcemia (serum calcium ≤ 2.13 mmol/L) in admission, showing higher 7-day (P = 0.021), 14-day (P = 0.002), 30-day (13.03% vs 4.98%, P = 0.002) mortalities than patients without hypocalcemia. Adjusting for variables in PESI, hypocalcemia was further revealed to be an independent predictor of 30-day mortality (P = 0.014). The optimal prediction rule contained hypocalcemia and 5 variables in PESI and sPESI, showing higher predictive validity [sensitivity (Sen): 0.930, specificity (Spec): 0.390, area under curve (AUC): 0.800] than PESI (Sen: 0.814, Spec: 0.367, AUC: 0.716) and sPESI (Sen: 0.907, Spec: 0.216, AUC: 0.703). Conclusions Hypocalcemia is an independent predictor of the mortality following acute PTE. Based on hypocalcemia, the optimal prediction rule showed higher validity than PESI and sPESI.

Background: Injury to the infrapatellar branch of the saphenous nerve (IBSN) is common during total knee arthroplasty (TKA) with a standard midline skin incision. Occasionally, painful neuromas form at the transection of nerve and cause pain and limitation of the range of motion of the knee joint. Case presentation: A 70-year-old woman experienced right knee pain and stiffness for 4 years after TKA. Physical assessment revealed medial tenderness; Tinel's sign was positive. Radiographs revealed that the prosthesis was wellplaced and well-fixed. She was diagnosed with arthrofibrosis and possible neuroma after TKA. She underwent right knee exploration, neurectomy, adhesiolysis and spacer exchange. The neuroma-like tissue was sent for pathological examination. The patient recovered uneventfully and at 3-month follow-up reported no recurrence of pain or stiffness. The pathological report confirmed the diagnosis of neuroma. Conclusions: IBSN injury should be a concern if surgeons encounter a patient who has pain and stiffness after TKA. Tinel's sign, local anesthetic injection, MRI and ultrasound could help the diagnosis and identify the precise location of neuroma. Surgical intervention should be performed if necessary.

Malignant triton tumor (MTT) is an extraordinarily uncommon and aggressive tumor which have poor prognosis. Malignant peripheral nerve sheath tumors with additional rhabdomyoblasts are found in MTT histologically. The prognosis of patients is poor. The goal of our study is to describe the largest number of cases characteristic and outcome, to our knowledge, such a presentation was not described in the English-language literature until now.From 1999 to 2014, 10 patients (5 women and 5 men) with a malignant triton tumor were treated at our institution. All these cases were followed-up and patient charts were analyzed for outcome.In our study, 3 cases of the Malignant triton tumors originate in the head, 2 cases in the joints, 2 cases in the retroperitoneum, 2 cases in the soft tissues of the thoracic wall, and 1 case in the prostate. Neoplasm associated with pain was the main manifestation. Patients have a poor prognosis. Completely surgical excision of the tumor is the only treatment. Additional radiation or chemotherapy show little effect.Malignant triton tumor is a rare sarcoma. The high probability of developing local recurrence and distant metastases could account for its poor prognosis.