Background : Conservative treatment exists for acute subdural hematoma. However, in some cases, hematoma increases in the subacute phase. Here, we report the analysis of predictive factors related to acute subdural hematoma that lead to hematoma increase in the subacute phase. Methods : We included patients with acute subdural hematoma who were hospitalized from 2003 through 2014 in the department of neurosurgery at our hospital. We excluded patients who had undergone an operation in the acute phase, had non-aggressive treatment, or had a cerebral contusion or acute epidural hematoma. We included 261 cases of acute subdural hematoma in the convexity. We compared cases in which hematoma increased in the subacute phase with those in which hematoma did not increase. Result : Forty-three cases demonstrated an increase in hematoma in the subacute phase. In 218 cases, hematoma did not increase. The following factors were predictive factors of increase of hematoma in the subacute phase : age, prevalence of diabetes mellitus, hematoma thickness, and midline shift. Conclusion : In elderly patients who were able to receive conservative treatment until the subacute phase, hematoma increased in the subacute phase.

　　The patient was a 16-year-old boy who was in a motorbike accident. He slipped on a manhole cover while riding, and was brought in by ambulance. No contusions were evident anywhere on the body, and no bone fractures were identified. We observed bilateral iliacus muscle hematoma on contrast-enhanced computed tomography with extravasation of contrast medium within those hematomas. Vital signs were stable, and we selected conservative treatment and admitted the patient. On the third day after injury, the patient complained of numbness in the left thigh, but numbness disappeared the following day. From the circumstances of the motorbike accident, we conjectured that both hip joints had experienced sudden hyperextension during the accident, resulting in hematomas within the iliacus muscles. If shock symptoms are absent and no progression of femoral nerve palsy is apparent, conservative treatment is valid for hematoma due to trauma in the iliopsoas muscle, including the iliacus muscle.

　　A 17-year-old man was injured in a bicycle accident. On admission his GCS was E2V3M5 with restlessness, and initial head CT revealed bifrontal brain contusion and right subdural hematoma. After we performed right burr hole surgery for the hematoma, we started hypothermia and barbiturate therapy while monitoring ICP. On hospital day 2, ventricular drainage was performed when ICP reached more than 30 mmHg. On day 4, ICP reached high values again, and we confirmed brain swelling without mid-line-shift on CT. We decided to perform bifrontotemporoparietal decompressive craniectomy with coronary skin incision. After the surgery, the patient quickly finished intensive care, and his level of consciousness gradually improved. Cranioplasty was performed on day 44. He was released from the hospital on day 215 and returned to school. Craniectomy is effective for refractory raised intracranial pressure during head trauma intensive care.

　　Major replantation of the upper limbs is a frequent procedure due to the poor outcome of prosthetic substitutions. We report a case of an unsuccessful major upper limb replantation in a 40-year-old man. He had an occupational injury and major amputation in the middle one third of his forearm due to avulsion. There was a 10-cm defect in each of his median and ulnar nerves. In the first operation, reconstruction of vessels, and anatomical reduction and internal fixation of the radius and ulna were performed. However, reconstruction of the nerves was not performed. Ten days after the operation, we planned the reconstruction of his soft tissues with a latissimus dorsi flap and the transplantation of his nerves with bone shortening. However, bone shortening was impossible because of inflammation and oedema. Four months later, his limb became non-functional. This case suggests that primary bone shortening should be performed in the first operation of a major upper limb replantation.

　　Delayed hemorrhage is a serious complication of non-operative management in patients with splenic injury. Although splenic artery pseudoaneurysm has been suggested to be involved in this condition, the therapeutic approach in children is not clear. We report three cases with different clinical courses. Case 1 : No pseudoaneurysm was demonstrated at the time of admission. However, delayed bleeding occurred and pseudoaneurysm was evident on day 2 after injury, which was embolized. Case 2 : A pseudoaneurysm presented on admission was rapidly enlarged on day 3 after injury, for which embolization was performed. Case 3 : A pseudoaneurysm was diagnosed on the 8th day, which disappeared on angiography on the 13th day. Serial evaluation of vascular injury is essential in non-operative management for pediatric trauma patients with splenic injury. Selective splenic artery embolization should be considered for any pseudoaneurysm, even in pediatric trauma patients.

　　Duodenal injury in patients with abdominal trauma is relatively rare. We present three cases of pediatric traumatic duodenal perforation, with a review of the literature. Patient 1 was a 10-year-old girl who developed a bruise on the upper abdominal region due to a seat belt injury. Patient 2 was a 14-year-old boy who developed a bruise on the right lateral abdominal region following a roundhouse kick during a karate match. When these patients arrived at the emergency clinic, their vital signs were stable, but abdominal pain and peritoneal signs were noted. Abdominal CT revealed retroperitoneal fluid collection. The next day, an additional CT scan revealed free air around the duodenum. Patient 3 was a 14-year-old boy who developed a bruise on the right lateral abdominal region after being hit during a karate match. Abdominal CT revealed the presence of free air and intra-abdominal ascites.

　　We experienced a rare case in which a patient exhibited cerebrospinal fluid hypovolemia due to liquorrhea from sacral fracture and sacral cyst rupture following trivial trauma, and it was resolved with conservative treatment. A 68-year-old female visited our hospital on foot with a complaint of hip pain due to a fall. Diagnostic imaging revealed a cyst in the sacral spinal canal ; the cyst compressed the sacrum, and it had become thinner and fractured. It also showed cerebrospinal fluid leakage caused by the cyst rupture. Orthostatic headache with nausea and dizziness lead to a diagnosis of cerebrospinal fluid hypovolemia caused by liquorrhea. Although cerebrospinal fluid leakage had markedly increased on the following day, orthostatic headache gradually subsided with conservative treatment. On the 8th day, cerebrospinal fluid leakage had almost disappeared. Thereafter, she was gradually getting out of bed without any relapse of symptoms, and discharged in remission on the 21st day.