Long-term outcomes in patients treated with tissue-sparing posterior cervical fusion to revise a 1-level pseudarthrosis following ACDF.

STUDY DESIGN: Observational Study BACKGROUND: Symptomatic pseudarthrosis is one long-term complication in patients treated with anterior discectomy and fusion (ACDF). When revising a pseudarthrosis, a surgeon must decide to intervene posteriorly and/or anteriorly. Open posterior cervical fusion (PCF) is attractive for high rates of arthrodesis, however this technique introduces risks of added complications resulting from extensive soft tissue dissection. The purpose of this study was to assess long-term outcomes in patients undergoing tissue-sparing PCF with facet instrumentation to treat a single level pseudarthrosis. METHODS: Forty-five subjects were recruited from six participating sites. All subjects had a history of ACDF that was subsequently revised with tissue-sparing PCF to treat symptomatic pseudarthrosis at one level. Long-term radiographic assessments included flexion and extension X-ray and multi-planar CT. Subjects additionally completed a patient satisfaction questionnaire. Radiographs were assessed by investigators and an independent core imaging lab to diagnose implant integrity and arthrodesis at the revised levels. RESULTS: The revision procedure required a median 49 min to complete with an estimated blood loss of 10 cc. Subjects were discharged a median 1 day following treatment. There were no instances of hospital re-admission nor subsequent surgical interventions. Study follow-up assessments were performed a median 39 months from revision. Surgeons diagnosed complete fusion in 91 % of cases. The core imaging lab identified bridging bone across the revised segment in 80 % of cases. Range of motion was < 2° in 93 % of cases. Seventy-four percent of subjects reported being satisfied with their outcomes. CONCLUSIONS: This study summarizes long-term radiographic outcomes in a cohort of patients receiving tissue-sparing PCF for the treatment of pseudarthrosis. Assessed years after revision, patients achieved rates of arthrodesis similar to open PCF without the soft tissue dissection responsible for perioperative morbidity and long-term soft tissue pain.

Length of stay associated with posterior cervical fusion with intervertebral cages: experience from a device registry.

BACKGROUND: Using a multi-center medical device registry, we prospectively collected a set of perioperative and clinical outcomes among patients treated with tissue-sparing, posteriorly-placed intervertebral cage fusion used in the management of symptomatic, degenerative neural compressive disorders of the cervical spine. METHODS: Cervical fusion utilizing posteriorly-placed intervertebral cages offers a tissue-sparing alternative to traditional instrumentation for the treatment of symptomatic cervical radiculopathy. A registry was established to prospectively collect perioperative and clinical data in a real-world clinical practice setting for patients treated via this approach. This study evaluated length of stay as well as estimated blood loss and procedural time in 271 registry patients. RESULTS: The median length of stay was 1.1, 1.1 and 1.2 days for patients having a stand-alone arthrodesis, revision of a pseudoarthrosis, and circumferential fusion (360°), respectively, and was not related to number of levels treated. Historical comparison to published literature demonstrated that average lengths of stay associated with open, posterior lateral mass fixation were consistently ≥4 days. Average blood loss (range, 32-75 mL) and procedural time (range, 51-88 min) were also diminished in patients having tissue-sparing, cervical intervertebral cage fusion compared to open posterior lateral mass fixation. CONCLUSIONS: Adoption of this tissue-sparing procedure may offer substantial cost-constraining benefits by reducing the length of post-operative hospitalization by, at least, 3 days compared to traditional lateral mass fixation.

Anterior Cervical Pseudarthrosis Treated with Bilateral Posterior Cervical Cages.

BACKGROUND: Pseudarthrosis after anterior cervical discectomy and fusion (ACDF) causes persistent pain and related disability. Posterior revision surgery results in higher healing rates, but is more extensive compared to anterior surgery. OBJECTIVE: To evaluate minimally disruptive, tissue sparing posterior fusion via bilateral placement of posterior cages between the facet joints as an alternative treatment option. METHODS: A retrospective, multicenter, medical chart review was performed and included 25 patients with symptomatic pseudarthrosis after ACDF treated with posterior cervical cages, and in select cases, anterior revision. Visual analog scale (VAS) for neck and arm pain, Neck Disability Index (NDI), and perioperative metrics were collected. Fusion at 1 yr was determined via assessment of computed tomography (CT) scan and x-rays. RESULTS: Mean follow-up was 18 mo. VAS neck and arm scores at last follow-up improved significantly from 7.9 ± 1.5 to 3.8 ± 2.3 and 7.24 ± 2.2 to 3.12 ± 2.5, respectively. NDI scores decreased from 65.1 ± 20.3 to 29.1 ± 17.9 at 18 mo. Fusion at 1 yr was confirmed by CT in all 17 patients with available scans and by x-ray in all 25 patients. CONCLUSION: Revision of cervical pseudarthrosis after ACDF using a tissue sparing posterior approach to place cages bilaterally between the facet joints is an effective surgical strategy in select cases. Along with positive clinical and radiological outcomes, the procedure is associated with less blood loss, shorter operating times, and briefer hospital stays compared to revision with lateral mass fixation or interspinous wiring.

Perioperative complications in patients treated with posterior cervical fusion and bilateral cages.

CONTEXT: Posterior cervical cages have recently become available as an alternative to lateral mass fixation in patients undergoing cervical spine surgery. AIMS: The purpose of this study was to quantify the perioperative complications associated with cervical decompression and fusion in patients treated with a posterior cervical fusion (PCF) and bilateral cages. SETTINGS AND DESIGN: A retrospective, multicenter review of prospectively collected data was performed at 11 US centers. SUBJECTS AND METHODS: The charts of 89 consecutive patients with cervical radiculopathy treated surgically at one level with PCF and cages were reviewed. Three cohorts of patients were included standalone primary PCF with cages, circumferential surgery, and patients with postanterior cervical discectomy and fusion pseudarthrosis. Follow-up evaluation included clinical status and pain scale (visual analog scale). STATISTICAL ANALYSIS USED: The Wilcoxon test was used to test the differences for the data. The P level of 0.05 was considered significant. RESULTS: The mean follow-up interval was 7 months (range: 62 weeks - 2 years). The overall postsurgery complication rate was 4.3%. There were two patients with neurological complications (C5 palsy, spinal cord irritation). Two patients had postoperative complications after discharge including one with atrial fibrillation and one with a parietal stroke. After accounting for relatedness to the PCF, the overall complication rate was 3.4%. The average (median) hospital stay for all three groups was 29 h. CONCLUSIONS: The results of our study show that PCF with cages can be considered a safe alternative for patients undergoing cervical spine surgery. The procedure has a favorable overall complication profile, short length of stay, and negligible blood loss.

Novel instrumentation and technique for tissue sparing posterior cervical fusion.

Authors have developed a simple, disposable instrument set for posterior cervical fusion (PCF). The instruments and technique minimize soft tissue disruption and facilitate access for cervical facet joint cartilage decortication. Technique is proposed for select patients not requiring laminectomy.

Percutaneous posterior cervical fusion with the DTRAX Facet System for single-level radiculopathy: results in 60 patients.

OBJECT: The authors present 1-year results in 60 patients with cervical radiculopathy due to spondylosis and stenosis that was treated with a bilateral percutaneous facet implant. The implant consists of a screw and washer that distracts and immobilizes the cervical facet for root decompression and fusion. Clinical and radiological results are analyzed. METHODS: Between 2009 and 2011, 60 patients were treated with the DTRAX Facet System in a multicenter prospective single-arm study. All patients had symptomatic clinical radiculopathy, and conservative management had failed. The majority of patients had multilevel radiographically confirmed disease. Only patients with single-level radiculopathy confirmed by history, physical examination, and in some cases confirmatory nerve blocks were included. Patients were assessed preoperatively with Neck Disability Index, visual analog scale, quality of life questionnaire (Short Form-12 version 2), CT scans, MRI, and dynamic radiographs. Surgery was percutaneous posterior bilateral facet implants consisting of a screw and expandable washer and iliac crest bone aspirate. Patients underwent postoperative assessments at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year with validated outcome questionnaires. Alterations of segmental and overall cervical lordosis, foraminal dimensions, device retention and fusion criteria were assessed for up to 1 year with CT reconstructions and radiographs. Fusion criteria were defined as bridging trabecular bone between the facets, translational motion < 2 mm, and angular motion < 5°. RESULTS: All patients were followed to 1 year postoperatively. Ages in this cohort ranged from 40 to 75 years, with a mean of 53 years. Forty-two patients were treated at C5-6, 8 at C6-7, 7 at C4-5, and 3 at C3-4. Fifty-six had bilateral implants; 4 had unilateral implants due to intraoperative facet fracture (2 patients) and inability to access the facet (2 patients). The Neck Disability Index, Short Form-12 version 2, and visual analog scale scores were significantly improved at 2 weeks and remained significantly improved up to 1 year. At the treated level, 93% had intrafacet bridging trabecular bone on CT scans, translational motion was < 2 mm in 100% and angular movement was < 5° in 83% at the 1-year follow-up. There was no significant change in overall cervical lordosis. There was a 1.6° loss of segmental lordosis at the treated level at 1 year that was significant. Foraminal width, volume, and posterior disc height was significantly increased at 6 months and returned to baseline levels at 1 year. There was no significant decrease in foraminal width and height at adjacent levels. There were no reoperations or surgery- or device-related complications, including implant failure or retained hardware. CONCLUSIONS: Results indicate that the DTRAX Facet System is safe and effective for treatment of cervical radiculopathy.