Influence of Cage Geometry on Sagittal Alignment in Instrumented Posterior Lumbar Interbody Fusion

Gödde, Stefan; Fritsch, Ekkehard; Dienst, Michael; Kohn, Dieter

doi:10.1097/01.brs.0000083167.78853.d5

Cited by 116 publications

(68 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…With regard to cage shape, it has been shown that lordotic 'wedged' cages or structural allograft results in greater monosegmental lordosis than non-wedged cages [15,[32][33][34][35]. However, the effect of other cage parameters such as cage height and length has not been previously assessed.…”

Section: Discussionmentioning

confidence: 99%

Do position and size matter? An analysis of cage and placement variables for optimum lordosis in PLIF reconstruction

2017

View full text Add to dashboard Cite

Purpose To examine monosegmental lordosis after posterior lumbar interbody fusion (PLIF) surgery and relate lordosis to cage size, shape, and placement. Methods Eighty-three consecutive patients underwent single-level PLIF with paired identical lordotic cages involving a wide decompression and bilateral facetectomies. Cage parameters relating to size (height, lordosis, and length) and placement (expressed as a ratio relative to the length of the inferior vertebral endplate) were recorded. Centre point ratio (CPR) was the distance to the centre of both cages and indicated mean position of both cages. Posterior gap ratio (PGR) was the distance to the most posterior cage and indicated position and cage length indirectly. Relationships between lordosis and cage parameters were explored. Results Mean lordosis increased by 5.98°(SD 6.86°). The cages used varied in length from 20 to 27 mm, in lordosis from 10°to 18°, and in anterior cage height from 10 to 17 mm. The mean cage placement as determined by CPR was 0.54 and by PGR was 0.16. The significant correlations were: both CPR and PGR with lordosis gain at surgery (r = 0.597 and 0.537, respectively, p \ 0.001 both), cage lordosis with the final lordosis (r = 0.234, p \ 0.05), and anterior cage height was negatively correlated with a change in lordosis (r = -0.297, p \ 0.01).Conclusion Cage size, shape, and position, in addition to surgical technique, determine lordosis during PLIF surgery. Anterior placement with sufficient ''clear space'' behind the cages is recommended. In addition, cages should be of moderate height and length, so that they act as an effective pivot for lordosis.

show abstract

Section: Discussionmentioning

confidence: 99%

Do position and size matter? An analysis of cage and placement variables for optimum lordosis in PLIF reconstruction

2017

View full text Add to dashboard Cite

show abstract

“…The expandable design of the VariLift ® -L converts the low-profile cylindrical implant to a wedge shaped implant when fully deployed to support preservation of lumbar lordosis. Previous reports have established the importance of restoring and maintaining lordosis with stand-alone cage technologies (12)(13)(14). Additionally, with the PLIF procedure, two bilateral devices are implanted (Figure 1), providing maximal endplate contact which has been shown to be preferable (15).…”

Section: Discussionmentioning

confidence: 99%

One and two level posterior lumbar interbody fusion (PLIF) using an expandable, stand-alone, interbody fusion device: a VariLift® case series

Barrett-Tuck

Monaco²,

Block

2017

J. Spine Surg.

View full text Add to dashboard Cite

Background: Surgical interventions such as posterior lumbar interbody fusion (PLIF) with and without posterior instrumentation are often employed in patients with degenerative spinal conditions that fail to respond to conservative medical management. The VariLift ® Interbody Fusion System was developed as a stand-alone solution to provide the benefits of an intervertebral fusion device without the requirement of supplemental pedicle screw fixation. Methods:In this retrospective case series, 25 patients underwent PLIF with a stand-alone VariLift ® expandable interbody fusion device without adjunctive pedicle screw fixation. There were 12 men and 13 women, with a mean age of 57.2 years (range, 33-83 years); single level in 18 patients, 2 levels in 7 patients.Back pain severity was reported as none, mild, moderate, severe and worst imaginable at baseline, 6 and 12 months. Preoperatively, 88% (22 of 25) of patients reported severe back pain.Results: All patients experienced symptomatic improvement and, by 12 months postoperatively, 71% (15 of 21) of patients reported only mild residual pain. Overall, pain scores improved significantly from baseline to 12 months (P=0.0002). There were no revision surgeries and fusion was achieved 12 of 13 patients (92%) who returned for a 12-month radiographic follow-up. There were three cases of intractable postsurgical pain which required extended hospitalization or pain management, one wound infection and one case of surgical site dehiscence, both treated and resolved during inpatient hospitalization. Conclusions:In this single-physician case series, the VariLift ® device used in single or two-level PLIF provided effective symptom relief and produced a high fusion rate without the need for supplemental fixation.

show abstract

“…There are reports that fusion can significantly reduce lumbar lordosis [36], and that this reduction correlates with postoperative back pain [37,38]. However, whether lumbar total disc replacement will influence lumbar lordosis and whether the lumbar lordosis correlates with clinical outcome are controversial [39][40][41].…”

Section: Discussionmentioning

confidence: 99%

An 11-year minimum follow-up of the Charite III lumbar disc replacement for the treatment of symptomatic degenerative disc disease

Hai

Kong

et al. 2015

Eur Spine J

View full text Add to dashboard Cite

Purpose To report our 11-year minimum clinical and radiological outcomes, as well as complications of the Charite III total disc replacement (TDR). Methods A total of 35 patients indicated for total disc replacement were implanted with the Charite III prosthesis. Clinical evaluation included visual analog scale (VAS) for back pain and the Oswestry disability index (ODI). Radiological parameters of intervertebral disc height (IDH), range of motion (ROM), lumbar lordosis, lumbar scoliosis and prosthesis position were evaluated. Complications and reoperation rates were also assessed. Results Thirty-two patients had a minimum 11-year follow-up, and 33 prostheses were implanted. The mean follow-up time was 11.8 years, ranging from 11.3 to 13.8 years. Twenty-eight patients (87.5 %) had a successful outcome, as defined by the FDA. Reoperation was performed in 2 patients for adjacent segment degeneration and pedicle fracture (1 case each). Both VAS and ODI scores showed significant improvement compared to baseline. At the final follow-up, the ROM of both the index-and adjacent-level showed an obvious decrease. The IDH of the index level showed a tendency to decrease, but the difference was not significant. The IDH of adjacent levels were not significantly affected by the surgery. Mean lumbar lordosis was increased at the final follow-up, and lumbar scoliosis over 3°was observed in 12 patients (37.5 %), with a mean angle of 5.6°(range 3°-12°). Of all 35 prostheses, 15 were left-shifted, 3 were right-shifted and 14 were just in the middle. In the coronal plane, 25 were rated as ideally placed, 5 were discretely shifted, 4 were slightly shifted and 1 was markedly shifted. In the sagittal plane, only 12 prostheses were rated as ideally placed, 14 were discretely shifted and 9 were suboptimally placed. Prosthesis subsidence was noted in 3 (9.4 %) patients (the subsidence distances were 3.1, 4.2 and 2.8 mm, respectively). Heterotopic ossification was detected in 25 segments (71.4 %), consisting of Class-I heterotopic ossification in 7 segments (20.0 %), Class-II in 9 segments (25.7 %), and Class-III in 9 segments (25.7 %). Class-IV heterotopic ossification was not observed. Conclusion The cumulative survival was 100 % at a mean follow-up of 11.8 years. Clinical and radiological results were satisfactory and long-term clinical results were maintained for a mean follow-up of 11.8 years. Reoperation and complication rates are acceptable, and our study does not substantiate the fear of reoperation or late complications. The results of our long-term follow-up indicate that, with strict indication, TDR is a safe and effective procedure as an alternative to lumbar fusion.

show abstract

Influence of Cage Geometry on Sagittal Alignment in Instrumented Posterior Lumbar Interbody Fusion

Cited by 116 publications

References 18 publications

Do position and size matter? An analysis of cage and placement variables for optimum lordosis in PLIF reconstruction

Do position and size matter? An analysis of cage and placement variables for optimum lordosis in PLIF reconstruction

One and two level posterior lumbar interbody fusion (PLIF) using an expandable, stand-alone, interbody fusion device: a VariLift® case series

An 11-year minimum follow-up of the Charite III lumbar disc replacement for the treatment of symptomatic degenerative disc disease

Contact Info

Product

Resources

About