Total Fusion Rate Research Articles

Clinical efficacy of oblique lumbar interbody fusion combined with unilateral pedicle screw fixation via Wiltse approach in the treatment of lumbar spinal stenosis

To evaluate the efficacy of oblique lumbar interbody fusion combined with unilateral pedicle screw fixation via Wiltse approach in the treatment of lumbar spinal stenosis. From July 2017 to January 2019, 90 patients with lumbar spinal stenosis, including 38 males and 52 females, aged from 43 to 75 years old with an average of(59.9±8.8) years old, and were treated with oblique lumbar interbody fusion(OLIF) combined with Wiltse unilateral pedicle screw fixation. Surgical decompression and fixation was performed in 50 cases of single segment, 32 cases of double segments and 8 cases of three segments. The distribution of responsible segments included 8 cases of L2-L3, 12 cases of L3-L4 and 30 cases of L4-L5 on single segment, 10 cases of L2-L4 and 22 cases of L3-L5 on double segments, and 8 cases of L2-L5 on three segments. The operation time, blood loss and occurrence of complications were recorded, Visual analogue scale(VAS), Oswestry Disability Index(ODI) and SF-36 scale were used to evaluate clinical efficacy. Lumbar X-ray and MRI were taken at three days after operation, interverterbral space height, intervertebral foraminal height, interverterbral foraminal area, and spinal canal area were measured, and interbody fusion was evaluated according to CT at half a year after operation. All patients were followed up from 12 to 33 months, with an average of (20.2±6.6) months. Mean operation time was (103.3±35.9) min, and mean intraoperative blood loss was (70.4±17.8) ml. VAS of low back pain leg pain, and ODI decreased from 6.2±1.1, 6.1±0.9 and (59.9±4.2)% to 2.7±0.5, 2.5±0.5 and (31.3±8.8)%. SF-36 scale significantly increased from (37.2±3.1) to (54.9±6.1) at the six months postoperation(P<0.05). The intervertebral space height, intervertebral foraminal height, intervertebral foraminal area, and spinal canal area were significantly improved at 3 days after operation(P<0.05). Six months after operation, CT scan showed well fusion in 87 cases, but 3 cases with poor fusion, including 1 case of single segment, 2 cases of multi-segments. The total fusion rate was 96.7% (87/90), the single segment fusion rate was 98.0% (49/50), and the multi-segments fusion rate was 95.0%(38/40). The overall incidence of complications was 17.8%(16/90), including transient iliopsoas muscle weakness in 5 cases (5.6%), endplate fracture in 2 cases (2.2%), peritoneal injury in 1 case (1.1%), postoperative hematoma in 1 case (1.1%), adjacent segment disease in 1 case(1.1%), and fusion cage subsidence in 6 cases (6.7%). Three patients was followed up for recurrent nerve root pain and the symptoms were relieved after revision operation. All complications were relieved or disappeared in varying degrees during the follow-up period, and there were no complications such as cage displacement and screw fracture. OLIF combined with unilateral pedicle screw fixation via Wiltse approach is effective in treating lumbar spinal stenosis with minimally invasive advantages such as less trauma and less complications. Under the premise of strictly grasping the indications, this method could also achieve satisfactory clinical results in multi-segments oprations.

Early Fusion Rates After Direct Lateral Lumbar Interbody Fusion With Bone-Morphogenetic Protein.

Direct lateral (transpsoas) lumbar interbody fusion (LLIF) reportedly achieves union by 1 year postoperatively, but how soon fusion occurs after these minimally invasive procedures is unclear. This study investigated LLIF fusion progression at 6 months and 1 year in a large-scale cohort using bone morphogenetic protein (BMP) graft and examined risk factors associated with failed fusion. Patients undergoing primary LLIF with a single surgical team from 2015 through 2016 with polyetheretherketone (PEEK) iimplants and BMP graft were identified. Retrospective chart review included demographics and medical history, construct length and location, and concurrent L5-S1 fusion. Inclusion criteria included minimum 1-year follow-up and postoperative lumbar computed tomography at 6 months and 1 year, which was independently assessed for bony union at each level. 166 patients underwent LLIF at a total of 312 levels. Seventy-nine patients (48%) underwent 1-level fusion; 45 (27%), 2 levels; and 42 (25%), 3 or more levels. At 6 months, 160 (51%) levels showed fusion. At 1 year, 70% of the remainder were fused, and total fusion rate was 85%. Fusion rates from L1 through L4 were similar (84%-87%). Nonunion was not significantly associated with construct length (P = .19), concurrent anterior L5-S1 interbody fusion (P = .50), age (P = .70), BMI (P = .15), or comorbidities such as diabetes (P = .86) or thyroid disease (P = .46). This large retrospective cohort study corroborates prior 1-year LLIF fusion rate reports (85%) independent of construct length or location or medical comorbidities. Significantly, half showed fusion by 6 months, earlier than previously described and validating the efficacy of LLIF. 5. This study presents a large cohort of patients to support effective lumbar fusion after LLIF with BMP-2.

Arthrodesis of the Distal Interphalangeal Joint and the Thumb Interphalangeal Joint: A Retrospective Comparison of Kirschner Wires and the Acutrak 2 Headless Compression Screw

Background: Headless compression screws have become first choice for achieving arthrodesis in the distal interphalangeal joint and thumb interphalangeal joint. Only few comparisons between headless compression screws and other methods have been published. Objective: To assess healing and complication rate after arthrodesis of the distal interphalangeal joint or the thumb interphalangeal joint using a headless compression screw or Kirschner wires. Methods: A retrospective analysis of 148 consecutive primary fusions performed with the Acutrak 2 headless compression screw (n=107) or K-wires (n=41) was conducted. Healing was assessed clinically and radiographically at 6 to 8 weeks postoperatively. Results: In 89% of cases fusion had been achieved at 6 to 8 weeks postoperatively using the headless compression screw. 7 cases healed after 8 weeks. Secondary surgery with screw removal was required in 11 cases due to screw prominence, infection or non-union. In 71% of cases fusion had been achieved at 6 to 8 weeks postoperatively using Kirschner wires showing a lower fusion rate at this stage as compared to the headless compression screw group (p&lt;0.05). 9 joints in the Kirschner wire group fused at some point after 8 weeks of follow up yielding a total fusion rate of 93% which was similar to 96% in the headless compression screw group (p&gt;0.05). One infection occurred in the Kirschner wire group. Conclusion: Arthrodesis can be achieved with either a headless compression screw or Kirschner wires both showing equivalent total fusion rates though fusion may occur earlier using a headless compression screw.

Clinical application of intraosseous internal fixation in ankle-foot arthrodesis

Objective To investigate the short-to medium-term therapeutic effects of a new internal fixation device, intraosseous internal fixation (IO-FIX), in the foot-ankle arthrodesis. Methods From August 2016 to December 2018, 32 patients (40 feet) underwent foot-ankle arthrodesis with IO-FIX at De-partment of Orthopaedic Surgery, The Ninth People’s Hospital of Shanghai.They were 6 males and 26 fe-males, aged from 23 to 83 years (61.7±15.1 years).There were 28 cases (36 feet) of hallux valgus, 2 cases (2 feet) of ankle arthritis, one case (1 foot) of ankle rheumatoid arthritis and one case (1 foot) of naviculocuneiform arthrosis.The therapeutic effects were assessed in terms of imaging evaluation, American Orthopaedic Foot and Ankle Society (AOFAS) score, fusion rate and full weight-bearing time. Results The follow-up ranged from 3.0 to 31.3 months (mean, 12.6 months).The total fusion rate was 95.0%(38/40); the total AOFAS score increased significantly from preoperative 41.9±9.5 to postoperative 86.9±4.7 (P< 0.05).The 28 patients (36 feet) with hallux valgus achieved a successful fusion rate of 97.2%(35/36) and full weight-bearing at 8 weeks after operation.Their fusion time ranged from 45 to 64 days (57.1 days).Their metatarsophalangeal angle was decreased significantly from 52.1°±13.5° preoperatively to 13.4°±4.9° postoperatively and their 1-2 intermetatarsal angle significantly from 14.5°±2.4° to 8.9°±2.4° (P<0.05). Their AOFAS ankle-hindfoot score was improved significantly from 41.8±9.9 to 87.0±4.8 (P<0.05). All the 3 cases of ankle arthrodesis achieved good bone union and full weight-bearing within 12 weeks and their AOFAS ankle-hindfoot score was improved significantly from preoperative 43.4±3.5 to 86.3±3.5 at the final follow-up. Conclusion In foot-ankle joint arthrodesis, due to advantages of stable fixation, zero profile, limited soft tissue irritation, reinforced bone bridge and easy reproducibility, IO-FIX can lead to satisfactory short-to mid-term therapeutic effects. Key words: Foot; Arthrodesis; Internal fixators

TMPRSS2-ERG gene fusion in Turkish patients with localized prostate cancer: results of radical prostatectomy specimens.

Our aim was to evaluate and determine the frequency of Transmembrane protease, serine 2 (TMPRSS2)-ERG fusion in Turkish patients with clinically localized prostate cancer by using immunohistochemistry and reveal its relationship with clinicopathologic variables. Radical prostatectomy specimens of 99 patients, who underwent radical retropubic prostatectomy for localized cancer, between January 2002 and December 2011 were analyzed in the study. To detect ERG fusions, monoclonal ERG antibodyclone ID: EPR3864 (Epitomics, San Diego, CA, USA) and monoclonal anti-ERG antibody (9FY) (BiocareMedical, LLC, USA) were used. The immunistochemical expression of ERG protein was assessed as positive or negative regardless of stain intensity. Patients' age, total and primary Gleason scores, PSA levels, prostate volumes, tumor volumes, tumor stages and perineural invasion status were analysed retrospectively. Total fusion rate and correlation between the variables and fusion were evaluated. Mean age, prostate volume, tumor volume, PSA value of 99 patients were 62.02 years (±5.93), 50.02 cc (±20.67), 3.19 cc (±4.16), and 9.34 ng/mL (±3.37) respectively. TMPRSS2-ERG fusion was seen in 46 (46.5%) of 99 patients. When the variables analysed with independent samples t test to predict fusion (+) status, none of them was found to be statistically significant. When evaluated by logistic regression analysis for (+) or (-) status, only tumor stage was found to be statistically significantly correlated with fusion (p=0.049). The incidence of TMPRSS-ERG fusion in patients with localised prostate cancer in our study with Turkish population was found as 46.5%. Only tumor stage correlated with TMPRSS2-ERG fusion.

Unilateral versus bilateral pedicle screw instrumentation for single-level minimally invasive transforaminal lumbar interbody fusion

Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) has become an increasingly popular method of lumbar arthrodesis. However, there are few published studies comparing the clinical outcomes between unilateral and bilateral instrumented MIS TLIF. Sixty-five patients with degenerative lumbar spine disease were enrolled in this study. Thirty-one patients were randomized to the unilateral group and 34 to the bilateral group. Recorded demographic data included sex, age, preoperative diagnosis, and degenerated segment. Operative time, blood loss, hospital stay length, complication rates, and fusion rates were also evaluated. The Oswestry Disability Index (ODI) score and Visual Analog Scale (VAS) pain score data were obtained. All patients were asked to follow-up at 3 and 6months after surgery, and once every 6months thereafter. The mean follow-up was 26.6months (range 18–36months). The two groups were similar in sex, age, preoperative diagnosis, and operated level. The unilateral group had significantly shorter operative time, lower blood loss, and shorter hospital time than the bilateral group. The average postoperative ODI and VAS scores improved significantly in each group. No significant differences were found between the two groups in relation to ODI and VAS. All patients showed evidence of fusion at 12months postoperatively. The total fusion rate, screw failure, and general complication rate were not significantly different. Results showed that single-level MIS TLIF with unilateral pedicle screw fixation would be sufficient in the management of preoperatively stable patients with lumbar degenerative disease. It seems that MIS TLIF with unilateral pedicle screw instrumentation is a better choice for single-level degenerative lumbar spine disease.

Radiographic fusion rate after implantation of facet bone dowels

Background contextAchieving a posterolateral fusion in conjunction with performing decompressive laminectomies can prevent recurrence of stenosis or worsening of spondylolisthesis. Facet bone dowels have been introduced and marketed as a less invasive alternative to pedicle screws. Surgeons have been placing them during lumbar laminectomy surgery and coding for intervertebral biomechanical device and posterolateral fusion. These bone dowels have also been placed percutaneously in outpatient surgery centers and pain clinics for facet-mediated back pain. PurposeTo describe fusion outcomes in patients who underwent facet bone dowel placement. Study design/settingRetrospective analysis of a single center's experience. Patient sampleNinety-six patients comprise the entire cohort of patients who underwent facet bone dowel implantation at our institution with adequate postoperative imaging to determine fusion status. Outcome measuresFusion rates as determined on postoperative computed tomography (CT) scans and dynamic lumbar X-rays if CT is not available. MethodsThreaded facet bone dowels in this study were placed according to the manufacturer's recommended methods. The bone dowels were placed after open exploration of the facet complex or percutaneously through a tubular retractor on the contralateral side from a microdiscectomy or synovial cyst resection. The most recent available postoperative imaging was reviewed to determine fusion status. ResultsOf 96 patients in our series, 6 (6.3%) had a fusion seen on CT and 4 did not exhibit any movement on dynamic lumbar X-rays for a total fusion rate of 10.4% (10/96). Eighty-six (89.6%) patients were shown on imaging to not have a solid fusion either by visualizing a patent facet joint on CT or measurable movement between the flexion and the extension lumbar X-rays. ConclusionsThis article is mainly intended to question whether the implantation of facet bone dowels can produce a solid fusion radiographically. In our experience, the placement of facet bone dowels does not equal the time, skill, or attention to detail that is necessary for a posterolateral lumbar arthrodesis, and our follow-up radiographic studies clearly demonstrate an inadequate fusion rate.

Comparison of unilateral versus bilateral instrumented transforaminal lumbar interbody fusion in degenerative lumbar diseases

Transforaminal lumbar interbody fusion (TLIF) has become a well-established technique that is traditionally performed with bilateral pedicle screw (PS) fixation. There are only a small number of case reports of unilateral instrumented TLIF. To our knowledge, there have been few well-designed studies comparing unilateral versus bilateral instrumentation with TLIF. To compare clinical and radiographic outcomes in a selected series of patients treated with unilateral versus bilateral PS instrumented TLIF. Prospective randomized study in one unit. A total of 80 patients were enrolled in this study. Thirty-seven patients (17men and 20 women; average age 57.1 years) were randomized to the unilateral PS group and 43 patients (18 men and 25 women; average age 58.2 years) to the bilateral PS group. The demographic data collected from both groups were gender, age, preoperative index diagnosis, degenerated segment, and single/double level of fusion. Operative time, blood loss, hospital time, and implant costs were also evaluated. Postsurgical pain and functional results were analyzed by the visual analog scale (VAS), modified Prolo (mProlo) scores, and Oswestry Disability Index (ODI). Radiographic examinations were carried out to assess total fusion rates, screw failure, and general complications. Patients were randomized into the unilateral or bilateral PS instrumented TLIF group based on a computer-generated number list. Patients were asked to return to hospital for follow-up at 4 weeks, 3 months, 6 months, 12 months, and thereafter once a year after surgery. The mean follow-up was 25.3 months, with a range of 18 to 32 months. There were no significant differences between the two groups in terms of demographic data. The unilateral PS group had a significantly shorter operative time, less blood loss, and reduced implant costs compared with the bilateral PS group, although hospital time was the same for double-level cases. The average postoperative VAS, mProlo, and ODI scores improved significantly in both groups, with no significant difference between groups. The total fusion rate, screw failure, and general complication rate were not significantly different. Unilateral PS instrumented TLIF is a viable treatment option generating better results, especially in terms of operative time, blood loss, and hospital time for single-level disease and implant costs. No decrease in the fusion rate or increase in the complication rate was observed in this group. Further improved study design and a longer period of follow-up are needed to confirm this effect.

The short-term fusion rate of osteophyte filled cervical cage evaluated by a combination of CT, MR and X-ray film.

Objective To observe the short-term fusion rate of using osteophyte filled cage in ante-rior cervical disectomy and fusion. Methods From May 2007 to May 2009, 103 patients receiving anterior cervical disectomy, spine fusion by different surgeons were performed with cages containing exclusively au-tologous osteophyte collected from both anterior and posterior vertebral edges adjacent to the intervertebral space. There are 69 males, 34 females, from 25 to 77 years of age, average 53.6 years. 60 patients received one level fusion. 33 and 10 patients received two-level and three-level fusion respectively. Patients were re-viewed 3 months after operation and fusion was evaluated by X-ray film, reconstructive CT and MR. Results 1. Only 1.9% (2/103) of patients' X-ray films indicate non-fusion (internal fixation failure) while 31.7% (32/ 103) of patients' CT and 30.1% (31/103) of patients' MR indicate non-fusion or being confusing to make a diagnosis. 2. The diagnostic coherence between CT and MR as to evaluate fusion is good (kappa=0.686, P= 0.00). 3. The total fusion rate was 77.7%(80/103) while the highest fusion rate achieved by single surgeon was 90%(18/20). The total one level fusion rate was 80%(48/60) while the highest rate by single surgeon was 88.2%(15/17). The total two-level fusion rate was 78.6%(26/33) while the highest rate by single sur-geon was 90%(9/10). The total three-level fusion rate was 60%(60/100) while the highest rate by single surgeon was 100%(3/3). No statistic significant difference in fusion rate was found between any two of the three groups. Conclusion The method of using osteophyte filled cage can acquire ideal short-term fusion rate in one and two-level anterior cervical disectomy, fusion and plate fixation. Key words: Cervical vertebrae; Spinal fusion; Evaluation studies