MR investigation in evaluation of chronic whiplash alar ligament injury in elderly patients.

OBJECTIVE: To observe the imaging features for chronic whiplash alar ligament injury in elderly patients and to provide an effective diagnostic method for long-term neck pain and headaches due to alar ligament injury in elderly patients. METHODS: A total of 134 elderly patients, who engaged in the work or activities related to whiplash motion and suffered from chronic neck pain, were enrolled for the study. All patients were performed comprehensive health examination (CT, MR, ultrasound and laboratory examination) and high resolution PDWI. The patients were divided into 2 groups according to the results of comprehensive health examination: a clear etiology group(CE group, n=96) and an unknown etiology group(UE group, n=38). Th e characteristics of PDWI signal in the ligament were analyzed between the 2 groups. RESULTS: Th e anatomy and signal characteristics of the alar ligament were clearly displayed by high resolution PDWI. Th e alar ligaments were effectively displayed by oblique coronal image. In the CE group, 7 patients (7/96) showed the positive sign of ligament injured, while 21 (21/38) patients showed positive sign of ligament injured in the UE group (P<0.01). Chronic whiplash ligament injury was proved to be the reason for long-term neck pain and headaches in 15.7% patients. CONCLUSION: Th e whiplash injury of alar ligament is an important reason for chronic neck pain in elderly patients. High resolution PDWI is an effective method to evaluate the image features of alar ligament and can provide an accurate diagnosis for chronic neck pain and headaches caused by the alar ligament whiplash injury.

[3.0T-MR high resolution proton density weighted imaging for transverse cervical ligament in healthy adolescents].

OBJECTIVE: To explore the imaging characteristics of the transverse ligament in healthy adolescents, and further understand the imaging characteristics of the ligament injury. METHODS: We used 3.0T-MR to scan the transverse ligament with proton-weighted sequence in 32 young volunteers, scanned coronally, horizontally and sagittally, and then observed the morphology, thickness, running and signal characteristics of the ligament. RESULTS: The anatomy and signal characteristics of the transverse cervical ligament were clearly displayed by high resolution proton density weighted imaging (PDWI). The whole picture of the transverse ligament was effectively displayed by coronal combined with horizontal image. The transverse ligament was located in the rear of the odontoid, and connected to the inside of both sides of the block like half-arc. The length was (20.4±3.3) mm, the ligament center was the thickest, and both sides gradually became thinner. The middle width of the ligament was (7.3±0.6) mm, the ligament ends narrowed down, and the middle was (2.1±0.4) mm thick; 75% of the transverse ligament showed homogeneous low signal in PDWI, while 25% of the local transverse ligament had high signal. CONCLUSION: High resolution PDWI with 3.0T-MR is a effective method to evaluate the structure of the transverse cervical ligament. Local high signal may not necessarily be the sign of ligament injure. There may also be some high signal in the normal adolescent ligament, so we must pay much attention to clinical diagnosis and treatment.

[A comparative study of MAKO robotic arm assisted total hip arthroplasty and traditional total hip arthroplasty through posterolateral approach].

OBJECTIVE: To investigate the efficacy of total hip arthroplasty (THA) assisted by the MAKO robotic arm via posterolateral approach. METHODS: The clinical data of 70 patients treated with THA via posterolateral approach between March 2017 and March 2019 who met the selection criteria were retrospectively analyzed. According to different treatment methods, the patients were divided into two groups, 35 were treated with MAKO robotic arm assisted THA (MAKO group) and 35 with traditional THA (THA group). There was no significant difference in gender, age, body mass index, disease duration, etiology, perioperative time, preoperative activity of daily living (ADL) scale index, American Society of Anesthesiologists (ASA) classification, walking ability, comorbidities, hemoglobin, and other general data between the two groups ( P>0.05). The operation time, intraoperative blood loss, hospital stay, postoperative acetabular abduction and anteversion angles, postoperative length difference of bilateral lower limbs, and proportions of intraoperative blood transfusion, immediate postoperative loading, wound drainage time more than 2 days, and complications were recorded and compared between the two groups. According to the X-ray films at 6 months after operation, the reduction quality was judged. The forgotten joint score, Harris score, and proportions of independent walking and ADL index increased were used to evaluate the function recovery of patients. RESULTS: Patients in both groups were followed up 6-18 months, with an average of 8 months. There was no significant difference ( P>0.05) between the two groups in operation time, intraoperative blood loss, hospital stay, acetabular abduction and anteversion angles, and length difference of both lower limbs at 6 months after operation. There was no significant difference in the proportions of intraoperative blood transfusion, immediate postoperative loading, and wound drainage time more than 2 days between the two group ( P>0.05). X-ray reexamination at 6 months after operation showed that there was no significant difference in the reduction quality between the two groups ( Z=4.191, P=0.123). Postoperative complications occurred in 7 patients (20.0%) in the MAKO group and 10 patients (28.6%) in the THA group, showing no significant difference in the incidence of complications between the two groups ( χ 2=2.121, P=0.224). Two patients (5.7%) in the MAKO group and 4 patients (11.4%) in the THA group underwent revision within 6 months, showing no significant difference in the revision rate between the two groups ( χ 2=0.729, P=0.673). At 3 and 6 months after operation, the proportions of independent walking and ADL index increased showed no significant difference between the two groups ( P>0.05). Harris scores in both groups improved significantly when compared with preoperative scores ( P<0.05); there was no significant difference in the forgotten joint scores and Harris scores between the two groups ( P>0.05). CONCLUSION: Compared with traditional THA, MAKO robotic arm assisted THA has longer operation time and more intraoperative blood loss, but it has the advantages of accurate positioning and simple operation, and there is no significant difference in short-term postoperative function recovery.