RESUMEN
BACKGROUND: Primary intramedullary melanocytoma is an exceedingly rare type of primary melanocytic tumor in the central nervous system. Unfortunately, primary intramedullary melanocytoma lacks specificity in clinical symptoms and imaging features and there is currently no standard strategy for diagnosis or treatment. CASE SUMMARY: A 52-year-old male patient suffered from weakness and numbness involving the bilateral lower limbs for 18 mo, and defecation and erectile dysfunction for 6 mo. Furthermore, these symptoms started to worsen for the last 3 mo. Preoperative magnetic resonance imaging (MRI) revealed an intramedullary tumor located at the T9-T10 level. In subsequently surgery, the maximal safe resection extent approached to 98%. The lesion was confirmed to be melanocytoma by pathological examination. In addition, the possibility of original melanocytoma outside the spinal cord was excluded after the examination of the whole body. Therefore, a diagnosis of primary intramedullary melanocytoma was established. The patient refused to accept radiotherapy or Gamma Knife, but MRI examination on July 28, 2020 showed no sign of development. In addition, on April 10, 2021, the recent review showed that the disorder of defecation and lower limbs improved further but erectile dysfunction benefited a little from the surgery. CONCLUSION: After diagnosing intramedullary melanocytoma by postoperative pathology, the inspection of the whole body contributed to excluding the possibility of metastasis from other regions and further suggested a diagnosis of primary intramedullary melanocytoma. Complete resection, adjuvant radiation, and regular review are critical. In addition, maximal safe resection also benefits prognosis while the tumor is difficult to be resected totally.
RESUMEN
The distal radioulnar joint is not only the main load-bearing joint in the wrist, but also the pivot of the rotation of the forearm. It is one of the most important and unique joints in the body. Maintaining the stability of the distal radioulnar joint is very important for our daily life. The tissue to stabilize the distal radioulnar joint includes bone structures and soft tissue structures. Although the contribution of soft tissue structures to its stability is far exceeding that of bone structures, the influence of abnormal bone structure on the distal radioulnar joint cannot be ignored. By reviewing the relevant literatures, this article divides the bone structural abnormalities into congenital and acquired bone structural abnormalities. The effects of congenital and acquiredbone structural abnormalities on the distal radioulnar joint stability are analysized and collated in this article, and its clinical symptoms, clinical grading, clinical treatments are also summerized. The problems of distal radioulnar joint instability in clinical practicing and its future researching directions are briefly described in order to provide some suggestions for future clinical applications.
