The Effects of Immobilization of Long Segments of the Spine on the Adjacent and Distal Facet Force and Lumbosacral Motion

Nagata, Hiroto; Schendel, Michael J.; Transfeldt, Ensor E.; Lewis, Jack L.

doi:10.1097/00007632-199312000-00017

Cited by 190 publications

(93 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Various large animals, such as pig, calf, sheep, baboon, deer, goat and dog spines as models have been used for in vivo and in vitro spinal research [1,7,11,12,17,18,21,22]. In vitro models consisting of cadaveric spine specimens are useful in providing basic understanding of the functioning of the spine.…”

Section: Introductionmentioning

confidence: 99%

Anatomy of large animal spines and its comparison to the human spine: a systematic review

et al. 2009

View full text Add to dashboard Cite

Animal models have been commonly used for in vivo and in vitro spinal research. However, the extent to which animal models resemble the human spine has not been well known. We conducted a systematic review to compare the morphometric features of vertebrae between human and animal species, so as to give some suggestions on how to choose an appropriate animal model in spine research. A literature search of all English language peerreviewed publications was conducted using PubMed, OVID, Springer and Elsevier (Science Direct) for the years 1980-2008. Two reviewers extracted data on the anatomy of large animal spines from the identified articles. Each anatomical study of animals had to include at least three vertebral levels. The anatomical data from all animal studies were compared with the existing data of the human spine in the literature. Of the papers retrieved, seven were included in the review. The animals in the studies involved baboon, sheep, porcine, calf and deer. Distinct anatomical differences of vertebrae were found between the human and each large animal spine. In cervical region, spines of the baboon and human are more similar as compared to other animals. In thoracic and lumbar regions, the mean pedicle height of all animals was greater than the human pedicles. There was similar mean pedicle width between animal and the human specimens, except in thoracic segments of sheep. The human spinal canal was wider and deeper in the anteroposterior plane than any of the animals. The mean human vertebral body width and depth were greater than that of the animals except in upper thoracic segments of the deer. However, the mean vertebral body height was lower than that of all animals. This paper provides a comprehensive review to compare vertebrae geometries of experimental animal models to the human vertebrae, and will help for choosing animal model in vivo and in vitro spine research. When the animal selected for spine research, the structural similarities and differences found in the animal studies must be kept in mind.

show abstract

Section: Introductionmentioning

confidence: 99%

Anatomy of large animal spines and its comparison to the human spine: a systematic review

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Although most often the criteria to determine ASD are based solely on radiographic findings [2,7,19,28,30,34,39,41,59] reporting an ASD incidence ranging from 8 to 100%, the symptomatic incidence of ASD is significantly lower ranging from 5.2 to 18.5% [7,28,31], while the rate of re-operation rate for symptomatic ASD ranges from 2.7 to 20% [16,58].…”

Section: Introductionmentioning

confidence: 99%

“…There is a controversy regarding the risk factors involved in the development of ASD [2,11,12,22,28,40,41,47,[57][58][59]. Non-rigid, dynamic or flexible instrumentations for lumbar spine have been developed to reduce ASD [17,18,27].…”

Section: Introductionmentioning

confidence: 99%

Does Wallis implant reduce adjacent segment degeneration above lumbosacral instrumented fusion?

et al. 2009

View full text Add to dashboard Cite

Delayed complications following lumbar spine fusion may occur amongst which is adjacent segment degeneration (ASD). Although interspinous implants have been successfully used in spinal stenosis to authors' knowledge such implants have not been previously used to reduce ASD in instrumented lumbar fusion. This prospective controlled study was designed to investigate if the implantation of an interspinous implant cephalad to short lumbar and lumbosacral instrumented fusion could eliminate the incidence of ASD and subsequently the related reoperation rate. Groups W and C enrolled initially each 25 consecutive selected patients. Group W included patients, who received the Wallis interspinous implant in the unfused vertebral segment cephalad to instrumentation and the group C selected age-, diagnosis-, level-, and instrumentationmatched to W group patients without interspinous implant (controls). The inclusion criterion for Wallis implantation was UCLA arthritic grade \II, while the exclusion criteria were previous lumbar surgery, severe osteoporosis or degeneration[UCLA grade II in the adjacent two segments cephalad to instrumentation. All patients suffered from symptomatic spinal stenosis and underwent decompression and 2-4 levels stabilization with rigid pedicle screw fixation and posterolateral fusion by a single surgeon. Lumbar lordosis, disc height (DH), segmental range of motion (ROM), and percent olisthesis in the adjacent two cephalad to instrumentation segments were measured preoperatively, and postoperatively until the final evaluation. VAS, SF-36, and Oswestry Disability Index (ODI) were used. One patient of group W developed pseudarthrosis: two patients of group C deep infection and one patient of group C ASD in the segment below instrumentation and were excluded from the final evaluation. Thus, 24 patients of group W and 21 in group C aged 65? 13 and 64? 11 years, respectively were included in the final analysis. The follow-up averaged 60 ± 6 months. The instrumented levels averaged 2.5 ? 1 vertebra for both groups. All 45 spines showed radiological fusion 8-12 months postoperatively. Lumbar lordosis did not change postoperatively. Postoperatively at the first cephalad adjacent segment: DH increased in the group W (P = 0.042); ROM significantly increased only in group C (ANOVA, P \ 0.02); olisthesis decreased both in flexion (P = 0.0024) and extension (P = 0.012) in group W. The degeneration or deterioration of already existed ASD in the two cephalad segments was shown in 1 (4.1%) and 6 (28.6%) spines in W and C groups, respectively. Physical function (SF-36) and ODI improved postoperatively (P \ 0.001), but in favour of the patients of group W (P \ 0.05) at the final evaluation. Symptomatic ASD required surgical intervention was in 3 (14%) patients of group C and none in group W. ASD remains a significant problem and accounts for a big portion of revision surgery following instrumented lumbar fusion. In this series, the Wallis interspinous implant changed the natural history of ASD and saved th...

show abstract

“…Therefore, fusion generates controversy regarding immediate benefits and late consequences [5,14,30,48]. Negative effects in spine fusion have been reported, including pseudoarthosis, spinal stenosis, spondylolysis and accelerated degeneration of non-fused segments [5,28,39,44,48]. The main argument to fuse in thoracolumbar spine fractures is the lack of correction noticed in surgeries without arthrodesis, which is mainly caused by the degeneration of intervertebral discs involved in the fracture [3,9,27,30,31,37,38,43], or by the presence of capsuloligamentous disruptive injuries of the posterior column [34,40,55].…”

Section: Introductionmentioning

confidence: 99%

Residual mobility of instrumented and non-fused segments in thoracolumbar spine fractures

et al. 2006

View full text Add to dashboard Cite

The surgical management of thoracolumbar fractures presents potential benefits. However, the surgery solve the instability by fusion of mobile segments. We incorporate in our treatment algorithms, the use of restricted arthrodesis at injured levels, regardless of longer instrumentations, as well as the use of non-fused transitory stabilizations, based on the conviction that in non-fused segments without traumatic disc injury, mobility persists once the instrumentation is removed. The goals of this study were to compare the mobility of non-fused segments after hardware removal to a normal range of motion and to find prognostic pre-op imaging patterns. We reviewed 21 consecutive patients who underwent surgery with preservation of mobile segments (nonfused segments included in the construction) in order to recover mobility after removal of instrumentation, performed between 1995 and 2001. All patients were treated by indirect reduction with posterior transpedicular instrumentation. Clinical and radiological outcome was analyzed after an average follow-up of 46.6 months. Satisfactory subjective outcome results were obtained in 94.7%. The dynamic radiological follow-up study showed 75% (21 segments) with normal or decreased range of motion (ROM) and 25% (7 segments) without mobility. The non-fused segments with hardware removal before 10 months of evolution presented a normal or decreased mobility in 83.2% while the segments with hardware removal after 10 months showed 68.8% of mobility. The intervertebral disc (IVD)'s with normal initial MRI morphology preserved their mobility in 81.9%. Complications occurred in four patients: two superficial wound infections and two patients presented a late fracture of one USS Schanz. The results of this study prove that in thoracolumbar fractures, non-fused spinal segments included in pedicular instrumentation maintained mobility in a high percentage once the hardware is removed. 75% of the segments presented a normal or decreased ROM.

show abstract

The Effects of Immobilization of Long Segments of the Spine on the Adjacent and Distal Facet Force and Lumbosacral Motion

Cited by 190 publications

References 0 publications

Anatomy of large animal spines and its comparison to the human spine: a systematic review

Anatomy of large animal spines and its comparison to the human spine: a systematic review

Does Wallis implant reduce adjacent segment degeneration above lumbosacral instrumented fusion?

Residual mobility of instrumented and non-fused segments in thoracolumbar spine fractures

Contact Info

Product

Resources

About