Instrumented Posterolateral fusion versus instrumented Interbody fusion for degenerative lumbar diseases in uremic patients under hemodialysis.

BACKGROUND: Advances in hemodialysis have facilitated longer lifespan and better quality of life for patients with end stage renal disease (ESRD). Symptomatic degenerative lumbar diseases (DLD) becomes more common in patients with ESRD. Posterior instrumented fusion remains popular for spinal stenosis combining instability. Only a few sporadic studies mentioned about surgical outcomes in patients with ESRD underwent spine surgeries, but no one discussed about which fusion method was optimal for this kind of patients. In this study, we compared the differences between lumbar posterolateral fusion (PLF) and lumbar interbody fusion (IBF) in uremic patients underwent instrumented lumbar surgeries. METHODS: Between January 2005 and December 2017, ESRD patients under maintenance hemodialysis underwent posterior instrumented fusion for DLD were reviewed. A PLF group and an IBF group were identified. The demographic data was collected using their medical records. Clinical outcomes were evaluated by Oswestry Disability Index (ODI) and the visual analogue scale (VAS); radiographic results were assessed using final fusion rates. Any surgical or implant-related complication was documented. RESULTS: A total of 34 patients (22 women and 12 men, mean age of 65.4 years) in PLF group and 45 patients (26 women and 19 men, mean age of 65.1 years) in IBF group were enrolled. Both groups had similar surgical levels. The operation time was longer (200.9 vs 178.3 min, p = 0.029) and the amount of blood loss was higher (780.0 vs 428.4 ml, p = 0.001) in the IBF group. The radiographic fusion rate was better in the PLF group but without significant difference (65.2% vs 58.8%, p = 0.356). Seven in the PLF group and ten in the IBF group developed surgical complications (20.5% vs. 22.2%, p = 0.788); three patients in the PLF group (8.8%) and five patients in the IBF group (11.1%) received revision surgeries because of implant-related or wound complications. Comparing to preoperative ODI and VAS, postoperative ODI and VAS obtained significant improvement in both groups. CONCLUSIONS: Successful fusion rates and clinical improvement (VAS, ODI) were similar in IBF and PLF group. Uremic patients underwent IBF for DLD had longer length of operation and higher operative blood loss than underwent PLF.

Positive effect on spinal fusion by the combination of platelet-rich plasma and collagen-mineral scaffold using lumbar posterolateral fusion model in rats.

BACKGROUND: Platelet-rich plasma (PRP) is autologous in origin and contains a high concentration of platelets which is a source of various growth factors. Previous studies have suggested that PRP has a positive effect in accelerating fusion by an autologous bone graft in a lumbar fusion. The role of PRP on artificial bone grafts in spinal fusion remains controversial. In this study, positive effect on spinal fusion by PRP was hypothesized; in vitro and in vivo studies were designed to test this hypothesis. METHODS: PRP was produced from peripheral blood of Sprague-Dawley (SD) rats. A lumbar posterolateral arthrodesis model was used to test the efficacy of PRP on spinal fusion. Thirty SD rats were divided into three groups by different implants: the PRP group, PRP plus collagen-mineral carrier; the platelet-poor plasma (PPP) group, PPP plus collagen-mineral carrier; and the control group, collagen-mineral only. Spinal fusion was examined using plain radiographs, micro-computed tomography (micro-CT), manual palpation, and histological analysis. The fusion rate by micro-CT and that by manual palpation in groups were compared. RESULTS: In the micro-CT results, 16 fused segments were observed in the PRP group (80%, 16/20), 2 in the PPP group (10%, 2/20), and 2 in the control group (10%, 2/20). The fusion rate, determined by manual palpation, was 60% (6/10) in the PRP group, 0% (0/10) in the PPP group, and 0% (0/10) in the control group. Histology showed that the PRP group had more new bone and matured marrow formation. CONCLUSIONS: The results of this study demonstrated that PRP on an artificial bone carrier had positive effects on lumbar spinal fusion in rats. In the future, this composite could be potentially used as a bone graft in humans.

Clinical Outcomes of Percutaneous Endoscopic Lumbar Discectomy for Adjacent Lumbar Disc Herniation after Lumbar Posterolateral Fusion by Radiologic Evaluations

STUDY DESIGN: A retrospective study. OBJECTIVE: To analyze the effectiveness of percutaneous endoscopic lumbar discectomy (PELD) for adjacent lumbar disc herniation through radiologic evaluations. SUMMARY OF LITERATURE REVIEW: PELD minimizes posterior structural damage, allowing rapid rehabilitation. SUBJECTS AND METHODS: This study was conducted on 45 patients who were followed up for 1 year after PELD for adjacent lumbar disc herniation from March 2014 to February 2016. The modified Macnab criteria, the modified Suezawa and Schreiber score (MSS score), and visual analogue scales for the back (VAS-B) and legs (VAS-L) were evaluated. The disc height ratio and segmental angulation change were compared before posterolateral fusion and before PELD. Moreover, spinal stenosis was confirmed on magnetic resonance imaging (MRI) before PELD. RESULTS: Based on the modified Macnab criteria, 53.3% patients received an evaluation of at least “good,” and the mean MSS score improved from 4.77 to 6.99 at 1 year after the operation. The mean VAS-B score decreased from 7.02 to 4.67, and the mean VAS-L score decreased from 8.15 to 4.24 at 1 year after the operation. The mean disc height ratio was 87.1%, and the mean segmental angulation change was 6.5°, with a greater change in the “fair” or “poor” group, and the rate of spinal stenosis on MRI was also higher in the “fair” or “poor” group. CONCLUSION: The clinical outcomes of PELD, which is accompanied by degenerative changes on simple radiographic images such as disc space narrowing and increased segmental angulation or spinal stenosis on MRI, may not be satisfactory. Therefore, decisions regarding surgery should be made carefully in such cases.

The fate of adjacent segments with pre-existing degeneration after lumbar posterolateral fusion: the influence of degenerative grading.

PURPOSE: To evaluate the impact of pre-existing disc degeneration and its extent on future adjacent segment degeneration (ASDeg) after lumbar posterolateral fusion (PLF). METHODS: A total of 102 patients who had undergone PLF for degenerative lumbar diseases from January 2006 to December 2008 were retrospectively reviewed by using radiography and clinical evaluation. The University of California at Los Angeles (UCLA) grading scale was used to evaluate the extent of disc degeneration. The Visual Analog Scale, Oswestry Disability Index, and SF-36 questionnaire were used to evaluate clinical outcomes. RESULTS: The overall prevalence of radiological ASDeg was 25.5 %, and the prevalence of ASDeg for the cranial and caudal levels was 19.6 and 15.1 %, respectively. The prevalence of ASDeg in one-, two-, and three-level fusion was 15.8, 26.3, and 50 %, respectively (p = 0.008). For the cranial level, the preoperative UCLA grade A, B, and C groups had prevalence values for ASDeg of 13.5, 28.6, and 42.9 %, respectively (p = 0.026). A higher prevalence of ASDeg was found in cranial discs with pre-existing degeneration than in the group without pre-existing degeneration (p = 0.012). The group without pre-existing degeneration showed better outcomes. For the caudal level, there was no significant difference in ASDeg prevalence. At final follow-up, the group without pre-existing disc degeneration showed better outcomes than the group with pre-existing disc degeneration. CONCLUSIONS: Adjacent segment discs with pre-existing degeneration had a higher likelihood of ASDeg progression compared with normal discs, especially for those classified as UCLA grade C.

The first clinical trial of beta-calcium pyrophosphate as a novel bone graft extender in instrumented posterolateral lumbar fusion.

BACKGROUND: Porous ß-calcium pyrophosphate (ß-CPP) was developed to improve the fusion success of posterolateral lumbar fusion (PLF). The possibility of accomplishing PLF using a mixture of porous ß-CPP and iliac bone was studied. This paper reports the radiologic results of PLF using the ß-CPP plus autograft for lumbar degenerative disease as a bone graft extender. METHODS: A prospective, case-matched, radiographic study evaluating the results of short segment lumbar fusion using a ß-CPP plus autograft was performed to compare the efficacy of ß-CPP plus autograft with that of an autograft alone for short segment lumbar fusion. Thirty one consecutive patients (46 levels) underwent posterolateral fusion with pedicle screw fixation and additional posterior lumbar interbody fusion. In all patients, 3 mL of ß-CPP plus 3 mL of autogenous bone graft was placed randomly in one side of a posterolateral gutter, and 6 mL of autogenous iliac bone graft was placed on the other. The fusion rates, volumes of fusion masses, and bone absorption percentage were evaluated postoperatively using simple radiographs and 3 dimensional computed tomography (3D-CT) scans. RESULTS: The control sides treated with an autograft showed significantly better Lenke scores than the study sides treated with ß-CPP at 3 and 6 months postoperatively, but there was no difference between the two sides at 12 months. The fusion rates (confirmed by 3D-CT) were 87.0% in the ß-CPP group and 89.1% in the autograft group, which were not significantly different. The fusion mass volumes and bone absorption percentage at 12 months postoperatively were 2.49 mL (58.4%) and 1.89 mL (69.5%) for the ß-CPP and autograft groups, respectively, and mean fusion mass volume was significantly higher in the ß-CPP group. CONCLUSIONS: ß-CPP combined with an autograft is as effective as autologous bone for grafting during instrumented posterolateral spinal fusion. These findings suggest that ß-CPP bone chips can be used as a novel bone graft extender for short-segment posterolateral spinal fusion.

The First Clinical Trial of Beta-Calcium Pyrophosphate as a Novel Bone Graft Extender in Instrumented Posterolateral Lumbar Fusion

BACKGROUND: Porous beta-calcium pyrophosphate (beta-CPP) was developed to improve the fusion success of posterolateral lumbar fusion (PLF). The possibility of accomplishing PLF using a mixture of porous beta-CPP and iliac bone was studied. This paper reports the radiologic results of PLF using the beta-CPP plus autograft for lumbar degenerative disease as a bone graft extender. METHODS: A prospective, case-matched, radiographic study evaluating the results of short segment lumbar fusion using a beta-CPP plus autograft was performed to compare the efficacy of beta-CPP plus autograft with that of an autograft alone for short segment lumbar fusion. Thirty one consecutive patients (46 levels) underwent posterolateral fusion with pedicle screw fixation and additional posterior lumbar interbody fusion. In all patients, 3 mL of beta-CPP plus 3 mL of autogenous bone graft was placed randomly in one side of a posterolateral gutter, and 6 mL of autogenous iliac bone graft was placed on the other. The fusion rates, volumes of fusion masses, and bone absorption percentage were evaluated postoperatively using simple radiographs and 3 dimensional computed tomography (3D-CT) scans. RESULTS: The control sides treated with an autograft showed significantly better Lenke scores than the study sides treated with beta-CPP at 3 and 6 months postoperatively, but there was no difference between the two sides at 12 months. The fusion rates (confirmed by 3D-CT) were 87.0% in the beta-CPP group and 89.1% in the autograft group, which were not significantly different. The fusion mass volumes and bone absorption percentage at 12 months postoperatively were 2.49 mL (58.4%) and 1.89 mL (69.5%) for the beta-CPP and autograft groups, respectively, and mean fusion mass volume was significantly higher in the beta-CPP group. CONCLUSIONS: beta-CPP combined with an autograft is as effective as autologous bone for grafting during instrumented posterolateral spinal fusion. These findings suggest that beta-CPP bone chips can be used as a novel bone graft extender for short-segment posterolateral spinal fusion.

Outcome of Different Grafted Bone in Lumbar Posterolateral Fusion / 대한척추외과학회지

OBJECTIVES: Using a retrospective analysis on the fusion rate and the postoperative improvement in symptoms, this study evaluated the clinical feasibility of a bone graft in lumbar fusion surgery in the following cases: (1) Group I: local autograft, (2) Group II: local autograft and iliac crest autograft, and (3) Group III: local autograft and customized heterograft. MATERIALS AND METHODS: Among the patients who had undergone a decompression and lumbar posterolateral fusion for various lumbar diseases, between January 1997 and December 1999, 178, in who 2 year follow-up observations had been possible, were selected for this study. The patients were allocated to 1 of 3 groups, Group I (47 patients), Group II (57 patients) and Group III (74 patients). For each group, the mean patient ages were 58.3, 49 and 62.4 years old, respectively, with male to female ratios of 24:23, 23:24 and 36:38. Postoperative radiographs were taken at 2 weeks, 3 months and 1 year, and further follow-up observations were conducted at 1-year intervals. The bone fusions was determined, along with the fusion rates, based on Lenke's criteria, and the post-operative clinical outcomes were evaluated as excellent, good, normal and poor, using Kim's method. A statistical analysis was performed with Chi-square tests. RESULTS: From the follow-up observations for over a year, the radiographic evaluations showed that the fusion rates of Groups I and II, over B: 86.6 and over B: 88.9%, were superior to the over B: 80.1% of Group III, but with no statistical significance. For the clinical outcomes, the 78.1 88% over good results were superior to the 69.4% of Group III, which also showed statistical significance. CONCLUSIONS: The selective use of customized heterograft was assumed to be effective in an insufficient autogenous bone or a difficult autogenous bone collection even though it causes significantly lower improvement in the symptoms.

Efficacy of Calcium Sulfate Pellets as Bone Graft Substitute in Lumbar Posterolateral Fusion

OBJECTIVE: The authors investigated the efficacy of the calcium sulfate(OsteoSet(r) pellets) as an autograft extender when used to perform posterolateral lumbar fusions. PATIENTS AND METHODS: Twenty patients who underwent lumbar posterolateral arthrodesis for various spinal diseases between October 1999 and March 2000 were evaluated. Arthrodesis was performed by transpedicular screw fixation and bone grafting with a mixture of autograft + calcium sulfate in a 1:1 ratio. At time intervals of 1, 2, 3, and 6 months, postoperative radiographs were obtained to review the resorption of calcium sulfate and the evidence of fusion. A modified Lenke scale was used to assess the status of the fusion. RESULTS: At 2 months after operation, the average modified Lenke scale score for the OsteoSet(r) pellets group was 3.8. However at 6 months after operation, the average modified Lenke scale score for the OsteoSet(r) pellets group was 1.8. Resorption of calcium sulfate pellets was revealed in all cases at 6 months after surgery. CONCLUSION: It is presumed that a combination of calcium sulfate and autograft can play a role as an effective autograft extender in the posterolateral spinal fusion.