Efficacy of polyetheretherketone rod hybrid surgery in preventing proximal junctional failure after adult spinal deformity surgery / 中华外科杂志

Objective: To investigate the clinical outcome and preventive effect of polyetheretherketone(PEEK) rod hybrid surgery on proximal junction failure(PJF) after long-segment fusion of adult spinal deformity. Methods: A retrospective study was conducted to analyze patients with degenerative scoliosis/kyphosis who underwent long-segment decompression and fusion surgery at Department of Orthopedics, Peking University First Hospital from January 2017 to December 2021. A total of 75 patients were included in the study, including 14 males and 61 females, aged (67.2±6.8)years (range:55 to 84 years). According to the operation method chosen by the patients, the patients were divided into PEEK rod hybrid group (20 cases) and traditional titanium rod group (55 cases). The general information of the patients was collected, and the coronal and sagittal parameters of the spine were measured before operation, at 1 month after operation, and at the last follow-up. The clinical effect of surgery was judged by the visual analogue scale (VAS) and Oswestry disability index (ODI). Whether proximal junctional kyphosis (PJK) and PJF occurred during the follow-up and the time of occurrence were recorded. Comparisons between groups were performed using independent sample t test, Mann-Whitney U test, χ2 test and Fisher's exact probability method. The data before and after surgery in the same group were compared using the paired sample t test and the Wilcoxon test. Results: There were no significant differences in age, gender, body mass index, bone mineral density, distal instrumented vertebrae, surgical segments, osteotomy method, operation time, and intraoperative bleeding between the two groups (all P>0.05). The follow-up time of the PEEK rod group was shorter(M(IQR)16.5(4.8) vs. 25.0(12.0),Z=-4.230,t<0.01). There were no significant differences in coronal, sagittal parameters, VAS, and ODI between the two groups before operation (all P>0.05). Postoperative coronal Cobb angle, pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, thoracic kyphosis, sagittal vertical axis (SVA), VAS, and ODI were significantly improved in both groups(all P<0.05). At the last follow-up, the SVA of the PEEK rod hybrid group was(3.74±2.40)cm, which was significantly lower than that of the titanium rod group (6.28±4.06)cm (t'=-3.318, P=0.002). At the last follow-up, the ODI of the PEEK rod hybrid group was 30.7±6.1, significantly better than the titanium rod group 39.3±17.2. PJK occurred in 2 patients (10.0%) in the PEEK rod hybrid group, and no PJF phenomenon was observed. In the titanium rod group, 18 patients (32.7%) developed PJK, and 11 patients (20.0%) developed PJF. There was a statistically significant difference in the incidence of PJF between the PEEK rod hybrid group and the titanium rod group (P=0.031). Conclusions: PEEK rod hybrid surgery can achieve good clinical results in the treatment of adult spinal deformities. Compared with traditional titanium rod surgery, it can significantly reduce the incidence of postoperative PJF and improve the clinical function of patients.

Anterior cervical discectomy and fusion to treat cervical spondylosis with sympathetic symptoms / 北京大学学报(医学版)

OBJECTIVE@#To investigate the clinical effectiveness of polytheretherketone (PEEK) cages assisted anterior cervical discetomy and fusion (ACDF) to treat cervical spondylosis with sympathetic symptoms.@*METHODS@#Retrospective analysis was undertaken for 39 patients who were diagnosed as cervical spondylosis with sympathetic symptoms and underwent ACDF with PEEK cages. Radiographs obtained before surgery, after surgery, and at the final follow-up were assessed for quality of fusion. The following criteria were used for assessing radiographic success of fusion: (1) endplate obliterated with no lucent lines; (2) obliteration of disc space by bony trabeculae; (3) less than 2°of intervertebral motion or 2 mm of motion between the spinous processes at the operated segment on flexion-extension lateral radiographs. The sympathetic symptoms including vertigo, headache, tinnitus, nausea and vomiting, heart throb, hypomnesia and gastroenterological discomfort were scored by 20-point system preoperatively, 2 months postoperatively and at the final follow-up. The recovery rate and clinical satisfaction rate were also evaluated. Surgical complications were also assessed.@*RESULTS@#They were followed up for at least one year. The mean follow-up was 15.6 months. Radiographs of the cervical spine at the last follow-up revealed a solid fusion with no signs of a pseudoarthrosis in 36 cases. In two patients delayed union and bony fusion were achieved at the end of 9 and 11 months. Pseudoarthosis was found in 1 case but the patient had no symptoms. The score of sympathetic symptoms before surgery, 2 months after surgery and at the final follow-up were 8.4±1.0,2.2±0.3,and 2.4±0.3, respectively. There were 22 excellent cases, 15 good cases, 1 fair case and 1 bad case in terms of RR. Good to excellent results were attained in 95% of theses patients. The sympathetic symptoms improved in all the patients and the score was significantly improved after surgery. There was one patient who had cerebral spinal fluid leakage but he recovered one week after surgery. Two patients felt a mild swallowing discomfort, but it disappeared within one month after surgery. Subcutaneous hematoma occurred in one patient due to obstructed drainage. It was cleared two days after surgery.@*CONCLUSION@#Cervical spondylosis patients with sympathetic symptoms may be managed successfully with ACDF using PEEK cages. Successful clinical results regarding symptom improvement and general satisfaction with the surgical procedure depend not only on obtaining successful decompression and radiographic fusion but also on patient selection.

Retrospective study of complication of interspinous implants for degenerative lumbar disease / 中华外科杂志

<p><b>OBJECTIVE</b>To summarize and analyze the complications of interspinous implants for degenerative lumbar disease.</p><p><b>METHODS</b>From September 2007 to September 2011, 177 cases with degenerative lumbar diseases were treated with interspinous implants. There were 99 male patients and 78 female patients, the average age was 44.5 years (26 - 71 years). According to the application interspinous dynamic stabilization system type were divided into the Wallis group (136 cases) and Coflex group (41 cases). The clinical results were assessed by visual analog scale (VAS) of pain on lumbar and lower limbers, lumbar Japanese Orthopedic Association (JOA) score and Prolo functional score. The radiological results including segmental lodosis and segement movement degree were assessed by lumbar X ray and dynamic X ray. Summarize and analyze the complications both during operation and post operation. Quantitative datas were compared by paried-samples t test and complication rate was compared by χ(2) test.</p><p><b>RESULTS</b>There were 168 cases had completed follow-up and the average time was 34.7 months (3 - 50 months). In the final follow-up, lumbar pain VAS, lower limber pain VAS, lumbar JOA score and Prolo functional score were better than pre-operation (t = 10.7, 7.9, 13.4 and 8.8, P < 0.01). Segment lodosis angles was 14° ± 4° which was less than pre-operation 19° ± 4° (t = 9.4, P < 0.01).Segment movement degree was larger in Coflex group (12.6° ± 3.1°) than in Wallis group (9.7° ± 2.7°) (t = 8.6, P < 0.05). Complication rate was 10.7% (18/168), which of Wallis group was 6.2% (8/130) and Coflex group was 26.3% (10/38) (χ(2) = 12.5, P < 0.01). In Wallis group, there were 3 cases with dura tear and cerebrospinal fluid leakage, 1 case with nerve root injury and foot drop, 2 cases with spacer breakage when implantation and change the implants and 2 cases with recurrence of lumbar disc herniation. In Coflex group, there was 1 case with dura tear and cerebrospinal fluid leakage, 2 cases with mild displacement post operation, 1 case with debridement for aseptic wound exudates, 1 case with implant removal for breakage 1 week post operation, 4 cases with recurrence of lumbar disc herniation and 1 case with lumbar disc herniation 6 months post operation of lumbar stenosis.</p><p><b>CONCLUSIONS</b>The application of interspinous implants for degenerative lumbar diseases is effective and relative safe, but would suffer from the risk of complications.</p>

Retrospective study of combined application of interspinous process fixation system and rigid fixation system for degenerative lumbar diseases / 中华外科杂志

<p><b>OBJECTIVE</b>To assess the efficacy and safety of combined application of interspinous process fixation system and rigid fixation system for degenerative lumbar diseases.</p><p><b>METHODS</b>From September 2007 to September 2008, 16 cases with degenerative lumbar diseases were treated with combined application of interspinous process fixation system and rigid fixation system. The clinical results were assessed by VAS of pain of lumbar and lower limbs, lumbar JOA score and Prolo functional score. The radiological results including implant position (interspinous process, pedicle screws and plates), spinous process fracture, segmental range of motion (the non-fusion fixation segment, and the intermediate segments between fused and non-fused segments) which were assessed by lumbar static and dynamic X rays.</p><p><b>RESULTS</b>All 16 cases obtained an average follow-up of 17.6 months. At final follow up, lumbar VAS, lower limbers VAS, lumbar JOA score and Prolo functional score were significant improved than those of pre-operation (lumbar VAS: 1.9 +/- 1.4 vs. 4.5 +/- 3.1; lower limbs VAS: 1.7 +/- 1.2 vs. 6.3 +/- 2.9; lumbar JOA score: 22.8 +/- 3.3 vs. 12.5 +/- 4.7; Prolo functional score: 8.3 +/- 1.2 vs. 4.0 +/- 2.3). Range of motion of the non-fusion fixation segment was (9.8 +/- 4.2) degrees and that of the intermediate segments between fused and non-fused segments was (13.2 +/- 3.5) degrees .</p><p><b>CONCLUSIONS</b>Combined application of interspinous process fixation system and rigid fixation system for degenerative lumbar diseases provides a new idea to avoid the multi-segment fusion fixation and pertinent potential problems. Short-term clinical results are successful.</p>

Effect of pedicle screw fixation with bone cement in lumbar / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the strength of pedicle screw fixation with bone cement in human cadaveric lumbar vertebral bodies by using biomechanical test.</p><p><b>METHODS</b>Twenty-four fresh frozen cadaveric lumbar vertebral bodies were randomly divided into 3 groups, which each group had 8 bodies. The bodies in the first group were drilled only. The bodies in the second group were drilled with tap. The bodies in the third group were drilled and the holes were enlarged by borer. Each vertebral body was drilled in both right and left sides, which one side served as control with the pedicle screws fixation only and another side served as testing side with the pedicle screw fixation with bone cement. The pullout strength was tested on both sides by using borer.</p><p><b>RESULT</b>There was significant difference of manifestation of pull-strength between the control side and the testing side in all groups (P < 0.001). For the manifestation of pull-strength of testing side in different groups, which had pedicle screw fixation with bone cement, there was no significant difference between the second group and third group, however, the difference between the first group and the second group and between the first group and third group were significant.</p><p><b>CONCLUSION</b>The pedicle screws with bone cements could significantly enhance the strength of fixation in cadaveric lumbar compared with pedicle screws only.</p>