Application of different ultrasonic osteotomy methods in cervical expansive open-door laminoplasty

English Keywords:Ultrasonic bone cutter  Laminoplasty  Osteotomy method

English Abstract:

  【Abstract】 Objectives: To investigate the different entry point and angle of bone cutting with ultrasonic bone cutter in patients underwent cervical expansive open-door laminoplasty(CEOL). Methods: 256 patients who were administrated in the Orthopedic Department of Peking University International Hospital from January 2016 to June 2020 were reviewed retrospectively. All the patients underwent CEOL and were divided into four groups according to different osteotomy access as followed. Group A, ultrasonic flake cutter withupright access in 64 cases; group B, improved ultrasonic flake cutter with vertical to lamina access in 69 cases; group C, improved ultrasonic hooked cutter with vertical to lamina access in 46 cases; group D, traditional osteotome in 77 cases. Open-door time, intraoperative blood loss, allogeneic blood transfusion, surgical complications related to osteotomy such as spinal cord injury, dura tear, and C5 paralysis. Japanese Orthopedic Association(JOA) scores before and 3 days after surgery, and the rates of improved JOA score were recorded. Results: All patients underwent C3-C7 CEOL. The open-door time of group A, B and C were significantly lower than that of group D(10.3±2.7min, 10.9±2.8min, 10.1±2.7min vs 13.3±2.8min)(P<0.05). Intraoperative blood loss in group B and C was significantly lower than that in group D(205.9±127.1ml, 226.5±104.9ml vs 273.5±164.3ml)(P<0.05), and there was no significant difference between group A and the other three groups(P>0.05). The rate of allogeneic blood transfusion in group A was significantly higher than that in group B, C and D(12.5% vs 2.9%, 2.2%, 2.6%)(P<0.05). The incidence of C5 paralysis in group A was significantly higher than that in group B, C and D(P<0.05), while there was no significant difference between the other 3 groups(P>0.05). The postoperative JOA score of all groups improved compared with preoperative JOA score(P<0.05), and there was no significant difference of the rates of improved JOA score, as well as of JOA score between preoperative and 3 days after surgery(P>0.05). Conclusions: The use of ultrasonic bone cutter in CEOL can significantly reduce the open-door time and intraoperative blood loss, and significantly improve the postoperative nerve function. Upright access at the traditional bone cutting point on the open side can increase the rate of allogeneic blood transfusion. Vertical to lamina access at the bone cutting point moved inwards by 1-2mm can reduce the rate of allogeneic blood transfusion, so can the hooked cutter.