Analysis of the Risk Factors for C5 Nerve Palsy After Cervical Posterior Open-Door Laminoplasty for Patients with Cervical Spondylotic Myelopathy-From the Perspective of Cervical Sagittal Parameters.

OBJECTIVE: This study was performed to explore the sagittal radiological parameters related to the occurrence of C5 nerve palsy after cervical posterior open-door laminoplasty for the patients with cervical spondylotic myelopathy. METHODS: Sixty-two patients who underwent cervical posterior open-door laminoplasty were reviewed retrospectively from March 2017 to March 2022. The C2-7 Cobb angle, C2-7 sagittal vertex axis, thoracic inlet angle, neck tilt, T1 slope, and encroachment ratio of ossification were measured on X-rays. The enrolled patients were divided into C5 nerve palsy and control groups. Logistic regression was performed to analyze the potential risk factors for the occurrence of C5 nerve palsy. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were used to evaluate the significance of the results and the optimal diagnostic value. RESULTS: The results of logistic regression showed that only the T1 slope and encroachment ratio were variables that were responsible for C5 nerve palsy (P = 0.024; P = 0.04). The ROC curve analysis for the T1 slope showed that the cutoff value was 21.3° and the AUC was 0.796. The ROC curve analysis for the encroachment ratio revealed that the cutoff value was 0.21 and the AUC was 0.763. Both analyses demonstrated good diagnostic value for C5 nerve palsy. CONCLUSIONS: The preoperative T1 slope and encroachment ratio were variables that were risk factors for C5 nerve palsy in patients who underwent cervical posterior open-door laminoplasty.

[Electromagnetic navigation interlocking intramedullary nail technology for treatment of femoral shaft fractures].

OBJECTIVE: To explore the value of electromagnetic navigation interlocking intramedullary nail in the treatment of femoral shaft fracture. METHODS: Between July 2012 and October 2013, 53 cases of femoral shaft fracture were treated. There were 40 males and 13 females, aged 16-52 years (mean, 38.3 years). The causes of injury were traffic accident in 28 cases, falling from height in 11 cases, falling in 7 cases, crush injury in 4 cases, and other in 3 cases. Of 53 cases, there were 3 cases of open fracture (Gustilo I degree) and 50 cases of closed fracture. Fracture was located in the proximal femur in 17 cases, middle femur in 29 cases, and distal femur in 7 cases. According to Winquist classification, 7 cases were rated as type I, 8 cases as type II, 22 cases as type III, and 16 cases as type IV; according to AO classification, 18 cases were rated as type 32-A, 28 cases as type 32-B, and 7 cases as type 32-C. The time from injury to operation was 3-11 days (mean, 5 days). Distal interlocking intramedullary nail was implanted using electromagnetic navigation. RESULTS: The distal locking nail operation with interlocking intramedullary nail was successfully completed under electromagnetic navigation; the one-time success rate of distal locking nail operation reached 100%; and the locking nail time was 5.0-9.5 minutes (mean, 7.0 minutes). Healing of incision by first intention was obtained after operation, and no complication of skin necrosis, infection, and sinus tract occurred. Fifty-three cases were all followed up 5-12 months (mean, 9 months). One case had hip pain and weaken middle gluteal muscle strength, and the symptoms disappeared after removing the nail. During the follow-up period, no broken nails, nail exit, infection, or re-fracture occurred. All fractures achieved clinical healing, and the healing time was 8-22 weeks (mean, 14.5 weeks). In 49 patients followed up 8 months, the Lysholm score was excellent in 44 cases, good in 4 cases, and acceptable in 1 case, with an excellent and good rate of 98%. CONCLUSION: Electromagnetic navigation system is safe and reliable, with the advantages of high positioning accuracy, short operation time, and no radiation, the clinical application of the system for distal locking nail operation can obtain excellent short-term effectiveness.