Circumferential cervical surgery for ossification of the posterior longitudinal ligament: a multianalytic outcome study

Surgical treatment of severe multilevel circumferential compressive myelopathy of the cervical spine: is circumferential procedure necessary?

OBJECTIVE

To determine the necessity of circumferential decompression and fusion in patients with severe multilevel cervical spondylotic myelopathy with circumferential cord compression.

METHODS

This prospective study involved 51 patients with severe multilevel circumferential cervical myelopathy underwent two-stage circumferential procedure between July 2008 and June 2010. VAS scores, satisfaction surveys and JOA scores and imaging studies were obtained. Twenty-three patients (45.1%) underwent two-stage surgery (group A); the other 28 patients (54.9%) were satisfied with the outcomes after first-stage surgery, and the second-stage surgery was avoided (group B). Age, sex and symptom duration did not differ between the groups.

RESULTS

Patients were followed up for 3-5 years (mean, 42.5 months). In group A, VAS and JOA scores significantly improved from 63.3 and 7.9 to 38.3 and 10.4, respectively, at 3 months after the first-stage operation and 10.2 and 12.7, respectively, at 3 months after the second-stage operation. In group B, the VAS and JOA scores significantly improved from 62.7 and 7.9 to 31.1 and 11.2 respectively, at 3 months and 18.2 and 12.4, respectively at 6 months. Patient satisfaction rate significantly increased from 43.5% after the first-stage operation to 82.6% after the second-stage operation in group A. In group B, this rate was 89.3%. In group A, cervical spine lordosis increased from 12.8° preoperatively to 18.5° (p < .0001) and 19.1° (p > .05) at 3 months after the first-stage and second-stage operations, respectively. In group B, lordosis significantly increased from 12.5° preoperatively to 18.8° at 3 months. The total complication rate did not significantly differ from the rates after a single surgery (either anterior or posterior).

CONCLUSION

Only 45.1% patients required surgery via both approaches. Therefore, a two-stage procedure is a rational choice and safe procedure. If outcomes are unsatisfactory after the first-stage operation, a second-stage operation can be performed.

Segmental Subtotal Corpectomy and Reconstruction With Titanium Cage and Anterior Plate for Multilevel Ossification of the Posterior Longitudinal Ligament

This retrospective study assessed the outcomes of segmental subtotal corpectomy with titanium cage reconstruction and anterior plate fixation for multilevel ossification of the posterior longitudinal ligament. The study included 34 patients with multilevel ossification of the posterior longitudinal ligament who underwent segmental subtotal corpectomy with titanium cage reconstruction and anterior plate fixation from June 2005 to May 2011. Clinical and radiologic data were obtained. Neurologic function was evaluated by Japanese Orthopedic Association scores before and after surgery. No death, paralysis, or other surgically associated injuries occurred. After surgery, the bone graft fusion was firm, with no cases of lack of postoperative bone fusion, broken or loose titanium plate and screws, dislodged titanium cage, or injury to the vertebral artery, nerve root, or spinal cord. Cerebrospinal fluid leakage occurred in 2 cases. Japanese Orthopedic Association scores improved from 6.74±1.82 preoperatively to 11.33±3.5 postoperatively (P<.05). Neurologic outcomes were excellent or good in 84.21% of patients at follow-up of 1 to 6 years. No postoperative cerebrospinal fluid leakage occurred. Reasonable and skilled operation of the pneumatic drill is the key to successful surgery. Anterior corpectomy with titanium cage reconstruction and plate fixation and drilling applications can directly remove the hypertrophy and ossification of the posterior longitudinal ligament and relieve spinal cord compression. This technique retained the integrity of the vertebrae, increasing the possibility of bone graft healing. Segmental subtotal corpectomy with titanium cage reconstruction and anterior plate fixation can be used for the treatment of multilevel ossification of the posterior longitudinal ligament. [Orthopedics. 2016; 39(6):e1140-e1146.].

Laminoplasty instead of laminectomy as a decompression method in posterior instrumented fusion for degenerative cervical kyphosis with stenosis

Background

Posterior laminectomy with instrumented fusion is a standard procedure for treating degenerative cervical kyphosis with stenosis (DCKS). Two major disadvantages of the surgery are adhesion of the dural membrane with significant disfiguring of cervical spine and a small fusion bed around the lateral mass. One of the advantages of laminoplasty over laminectomy is the protection of the dural membrane from adhesion through preservation of posterior bony elements. This study presents the surgical outcomes of laminoplasty, instead of laminectomy, as a decompression method applied in posterior instrumented fusion for DCKS.

Methods

A consecutive single center series of twenty cases between 2008 and 2011 were retrospectively reviewed. They were diagnosed as DCKS and received anterior cervical fusion followed by expansive open door laminoplasty and lateral mass or pedicle screw instrumented fusion. We collected the functional scores and changes of cervical curvature on the basis of dynamic lateral films preoperatively and postoperatively. We used computed tomography scans and magnetic resonance imaging (MRI) to evaluate the status of fusion and decompression.

Results

The mean age at the time of surgery was 67.6 ± 15.2 years. Half of the patients were older than 75 years. All functional scores and cervical lordotic curvatures markedly improved. No recurrence of spinal cord compression was caused by closure of opened laminae, according to MRI study that was conducted 12 months postoperatively. No pseudarthrosis or hardware loosening was observed 24 months postoperatively.

Conclusion

The surgical aims for DCKS are adequate decompression, correction of kyphosis, and solid instrumented fusion. Laminoplasty applied in cervical fusion as a decompression method seems to lead to a favorable functional recovery and reduces the complications of perineural adhesion that typically occur after laminectomy. In addition, laminoplasty affords an additional fusion bed at the hinge side and this advantage benefits solid fusion mass formation for the patients who suffered from DCKS.

Surgical outcome in patients with cervical ossified posterior longitudinal ligament: A single institutional experience

OBJECTIVE

Ossification of the posterior longitudinal ligament (OPLL) is a complex multi-factorial disease process having both metabolic and biomechanical factors. The role of surgical intervention as well as the choice of approach weather anterior or posterior is ambiguous. The objective of this study was to assess the surgical out come and post operative functional improvement in patients with cervical OPLL at a tertiary care centre.

PATIENTS AND METHODS

This prospective study included 63 patients of cervical OPLL who underwent either anterior and/or posterior surgeries in Department of Neurosurgery, Nizam's Institute of Medical Sciences, Hyderabad between June 2009 to May 2011. Patient's data including age, sex, pre and post operative functional status, radiographic findings and OPLL subtypes were recorded and analyzed over a follow up ranging up to minimum two years.

RESULTS

The mean age of the patients was 51.1 (range 30-80 years) involving 14 women and 49 men. Out of 63 patients, 14 patients underwent surgery by anterior approach (corpectomy and fusion) and all of them improved (P = 0.52). 49 patients underwent surgery by posterior approach where decompressive laminectomy was performed in 40, laminectomy with instrumentation was done in 5, laminoplasty was done in 3 and 1 patient underwent both anterior and posterior surgeries. Of those who underwent posterior surgery, 40 patients improved, 7 remained the same as their preoperative status (who were having signal intensity changes on T2W MRI) and 2 patients deteriorated in the immediate post operative period and then showed gradual improvement. All the patients were followed up for 24 months. The mean pre-operative Nurick grade was 2.82 which later on improved to 2.03 post surgery (P < 0.05). Minor complications included wound infections in two patients (1.26%).

CONCLUSIONS

Anterior cervical decompression and reconstruction is a safe and appropriate treatment for cervical spondylitic myelopathy in the setting of single or two level OPLL. Laminectomy or laminoplasty is indicated in patients with preserved cervical lordosis having three or more levels of involvement. Younger patients with good pre operative functional status and less than 2 levels of involvement have better outcome following anterior surgery.

Ti2448 pedicle screw system augmentation for posterior lumbar interbody fusion

STUDY DESIGN

A finite element analysis was used.

OBJECTIVE

To evaluate the feasibility of using the Ti-24Nb-4Zr-7.9Sn (Ti2448) pedicle screw system to augment single-level posterior lumbar interbody fusion (PLIF).

SUMMARY OF BACKGROUND DATA

The Ti-6Al-4V pedicle screw system increases the risk of adjacent disc degeneration and stress-shielding effect due to enormous rigidity. A titanium alloy with much lower elastic modulus, Ti2448, may help to resolve the complications.

METHODS

A finite element model of intact L3-S1 was established and then validated. Single-level PLIF at L4-L5 with or without a supplementary titanium-alloy pedicle screw system was simulated. A pure moment of 7.6 Nm and a 400 N preload was applied to the finite element model of PLIF, PLIF with the Ti-6Al-4V screw system, and PLIF with the Ti2448 screw system in flexion, extension, axial rotation, and lateral bending.

RESULTS

The axial displacement at the fusion level decreased to 64%, 72%, 84%, and 92% of screw-free status in flexion, extension, axial rotation, and lateral bending, respectively, after augmentation of the Ti2448 screw system, which was 1% to 3% lower than the performance of the Ti-6Al-4V system. The angular displacement at the fusion level with the Ti2448 system was similar to that of the Ti-6Al-4V system, only 2% lower in flexion. Compared with the Ti-6Al-4V system, the Ti2448 system suppressed the increase of intradiscal pressures at the upper adjacent disc in all bending directions, but only in extension and axial rotation at the lower adjacent disc; the maximum stress experienced by cages and screws was higher in all bending directions when augmented with the Ti2448 system.

CONCLUSION

Using the Ti2448 screw system is suggested for augmenting single-level PLIF because it induces less disc intradiscal pressure at adjacent levels and the stress-shielding effect at implant-bone surface with stabilization performance compared with the Ti-6Al-4V screw system.

Conservative management of ossification of the posterior longitudinal ligament. A review

OBJECT

Ossification of the posterior longitudinal ligament (OPLL) can result in significant myelopathy. Surgical treatment for OPLL has been extensively documented in the literature, but less data exist on conservative management of this condition.

METHODS

The authors conducted a systematic review to identify all reported cases of OPLL that were conservatively managed without surgery.

RESULTS

The review yielded 11 published studies reporting on a total of 480 patients (range per study 1-359 patients) over a mean follow-up period of 14.6 years (range 0.4-26 years). Of these 480 patients, 348 (72.5%) were without myelopathy on initial presentation, whereas 76 patients (15.8%) had signs of myelopathy; in 56 cases (15.8%), the presence of myelopathy was not specified. The mean aggregate Japanese Orthopaedic Association score on presentation for 111 patients was 15.3. Data available for 330 patients who initially presented without myelopathy showed progression to myelopathy in 55 (16.7%), whereas the other 275 (83.3%) remained progression free. In the 76 patients presenting with myelopathy, 37 (48.7%) showed clinical progression, whereas 39 (51.5%) remained clinically unchanged or improved.

CONCLUSIONS

Patients who present without myelopathy have a high chance of remaining progression free. Those who already have signs of myelopathy at presentation may benefit from surgery due to a higher rate of progression over continued follow-up.

Single stage circumferential cervical surgery (selective anterior cervical corpectomy with fusion and laminoplasty) for multilevel ossification of the posterior longitudinal ligament with spinal cord ischemia on MRI

OBJECTIVE

Anterior cervical corpectomy with fusion (ACF) or laminoplasty may be associated with substantial number of complications for treating multilevel cervical ossification of the posterior longitudinal ligament (OPLL) with significant cord compression. For more safe decompression and stabilization in multilevel cervical OPLL with prominent cord compression, we propose circumferential cervical surgery (selective ACF and laminoplasty) based on our favorable experience.

METHODS

Twelve patients with cervical myelopathy underwent circumferential cervical surgery and all patients showed multilevel OPLL with signal change of the spinal cord on magnetic resonance imaging (MRI). A retrospective review of clinical, radiological, and surgical data was conducted.

RESULTS

There were 9 men and 3 women with mean age of 56.7 years and a mean follow up period of 15.6 months. The average corpectomy level was 1.16 and laminoplasty level was 4.58. The average Japanese Orthopedic Association score for recovery was 5.1 points and good clinical results were obtained in 11 patients (92%) (p < 0.05). The average space available for the cord improved from 58.2% to 87.9% and the average Cobb's angle changed from 7.63 to 12.27 at 6 months after operation without failure of fusion (p < 0.05). Average operation time was 8.36 hours, with an estimated blood loss of 760 mL and duration of bed rest of 2.0 days. There were no incidences of significant surgical complications, including wound infection.

CONCLUSION

Although the current study examined a small sample with relatively short-term follow-up periods, our study results demonstrate that circumferential cervical surgery is considered favorable for safety and effectiveness in multilevel OPLL with prominent cord compression.

Gait analysis for evaluating the relationship between increased signal intensity on t2-weighted magnetic resonance imaging and gait function in cervical spondylotic myelopathy

OBJECTIVE

To determine relationships between increased signal intensity (ISI) on T2-weighted cervical spine magnetic resonance imaging (MRI) and parameters of gait analysis in patients with cervical spondylotic myelopathy (CSM).

DESIGN

Retrospective comparative study.

SETTING

Gait analysis laboratory.

PARTICIPANTS

Patients (N=36) who undertook cervical laminectomy or laminoplasty because of CSM.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Subjects were evaluated by using the modified Japanese Orthopaedic Association (JOA) scale, the Nurick scale, cervical spine MRI, and gait analysis. Two radiologists classified patients into 3 groups: intense, faint, and no ISI.

RESULTS

Relative to patients without ISI, those with ISI showed significantly slower gait speed, longer step time, decreased single-limb support time, increased double-limb support time, and limited range of motion of knee and ankle (P<.05). Increased intensity tended to correlate with poor gait function including slower gait speed, longer step time, decreased single-limb support time, and increased double-limb support time. The modified JOA and Nurick scale did not correlate with ISI.

CONCLUSIONS

In patients with CSM who received surgical treatment, more intense ISI on T2-weighted MRI correlated preoperatively with increased difficulties in gait function. Gait analysis may be a useful tool for evaluating gait functions in cervical myelopathy.

Noncontiguous anterior decompression and fusion for multilevel cervical spondylotic myelopathy: a prospective randomized control clinical study

Anterior decompression and fusion is an established procedure in surgical treatment for multilevel cervical spondylotic myelopathy (MCSM). However, contiguous corpectomies and fusion (CCF) often induce postoperative complications such as nonunion, graft subsidence, and loss of lordotic alignment. As an alternative, noncontiguous corpectomies or one-level corpectomy plus adjacent-level discectomy with retention of an intervening body has been developed recently. In this study, we prospectively compared noncontiguous anterior decompression and fusion (NADF) and CCF for MCSM in terms of surgical invasiveness, clinical and radiographic outcomes, and complications. From January 2005 to June 2007, 105 patients with MCSM were randomized to NADF group (n = 55) and CCF group (n = 50), and followed up for average 31.5 months (range 24-48 months). Average operative time and blood loss decreased significantly in the NADF group as compared with those in the CCF group (p < 0.05 and <0.001, respectively). For VAS, within 3 months postoperatively, there was no significant difference between the two groups. But at 6 months after surgery and final follow-up, VAS improved significantly in NADF group than that in CCF group (p < 0.05). No significant difference of JOA score was observed between the two groups at every collection time. In NADF group, all 55 cases obtained fusion at 1 year after operation (average 5.1 months). In CCF group, 48 cases achieved fusion 1 year postoperatively, but the other 2 cases were performed posterior stabilization and achieved fusion 6 months later. The differences of cervical lordosis between two groups were insignificant at the same follow-up time. But the loss of lordosis and height of fusion segments in 6 months postoperatively and final follow-up were significantly more in CFF group than in NADF group (p < 0.001). Complications were similar in both groups. But in CCF group three cases needed reoperation, one case with extradural hematoma was immediately re-operated after anterior decompression and two cases mentioned above were performed posterior stabilization at 1 year postoperatively. In conclusion, in the patients with MCSM, without developmental stenosis and continuous or combined ossification of posterior longitudinal ligaments, NADF and CCF showed an identical effect of decompression. In terms of surgical time, blood loss, VAS, fusion rate and cervical alignment, NADF was superior compared with CCF.

Ossification of the posterior longitudinal ligament of the cervical spine: histopathological findings around the calcification and ossification front

OBJECT

The authors studied the histological and immunohistochemical features of ossified posterior longitudinal ligament (PLL) of the cervical spine, especially in the calcification and ossification front.

METHODS

Samples of en bloc ossified PLL plaque obtained in 31 patients were stained with H & E and immunohistochemically prepared for collagens (types I and II), vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-beta, and bone morphogenetic protein (BMP)-2, and by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling method for apoptosis.

RESULTS

Enchondral ossification was evident between the ligamentous enthesis and deep layer of the ligament, with irregularly disorganized arrangement of elastic fibers in association with advancement of the degenerative process. In the ossification front, many hypertrophic metaplastic chondrocytes were noted in the ossifying plaque immediately contiguous to the ligament fibers, together with a considerable degree of neovascularization. Both TGFbeta and BMP-2 were highly expressed in metaplastic hypertrophic chondrocytes in the ossification front, and BMP-2 was also expressed in fibroblastic cells near the ossified PLL plaque. Expression of type I collagen was significant in the matrix of the ossified PLL lesion, whereas that of type II was marked in metaplastic chondrocytes in the ossification front. Apoptotic hypertrophic chondrocytes were observed mainly in the fibrocartilaginous area near the calcification front.

CONCLUSIONS

The enchondral ossification process in the ossified PLL was closely associated with degenerative changes of elastic fibers and cartilaginous cartilage formation, together with the appearance of metaplastic hypertrophic cartilage cells and neovascularization. The authors also found that VEGF-positive metaplastic chondrocytes in the ossification front and different expression patterns of collagens probably play some role in the extension of the ossified PLL from the ossification front.

Successful treatment of cervical myelopathy with minimal morbidity by circumferential decompression and fusion

Circumferential cervical decompression and fusion (CCDF) is an important technique for treating patients with severe cervical myelopathy. While circumferential cervical decompression and fusion may provide improved spinal cord decompression and stability compared to unilateral techniques, it is commonly associated with increased morbidity and mortality. We performed a retrospective analysis of patients undergoing CCDF at the University of California, San Francisco (UCSF) between January 2003 and December 2004. We identified 53 patients and reviewed their medical records to determine the effectiveness of CCDF for improving myelopathy, pain, and neurological function. Degree of fusion, functional anatomic alignment, and stability were also assessed. Operative morbidity and mortality were measured. The most common causes of cervical myelopathy, instability, or deformity were degenerative disease (57%) and traumatic injury (34%). Approximately one-fifth of patients had a prior fusion performed elsewhere and presented with fusion failure or adjacent-level degeneration. Postoperatively, all patients had stable (22.6%) or improved (77.4%) Nurick grades. The average preoperative and postoperative Nurick grades were 2.1 +/- 1.9 and 0.4 +/- 0.9, respectively. Pain improved in 85% of patients. All patients had radiographic evidence of fusion at last follow-up. The most common complication was transient dysphagia. Our average clinical follow-up was 27.5 +/- 9.5 months. We present an extensive series of patients and demonstrate that cervical myelopathy can successfully be treated with CCDF with minimal operative morbidity. CCDF may provide more extensive decompression of the spinal cord and may be more structurally stable. Concerns regarding operation-associated morbidity should not strongly influence whether CCDF is performed.

Ossificação do ligamento longitudional posterior: relato de caso

Ossificação do ligamento longitudinal posterior (OLLP) cervical é patologia rara em nosso meio que pode ser tratada por abordagem anterior ou posterior da coluna. Relatamos o caso de um homem japonês de 42 anos com paraparesia progressiva e TC e RM comprovando o diagnóstico de OLLLP, submetido a corpectomia anterior com artrodese. A fisiopatologia desta entesopatia, prevalência racial, quadro clínico, características radiológicas e opções do procedimento cirúrgico são revistos.

Dynamic anterior cervical plates for multilevel anterior corpectomy and fusion with simultaneous posterior wiring and fusion: efficacy and outcomes

STUDY DESIGN

To prospectively evaluate major complications associated with the application of dynamic ABC plates (Aesculap, Tuttlingen, Germany) to multilevel Anterior Corpectomy/Fusion (ACF) followed by posterior fusion (C2-C7 PF).

OBJECTIVES

To determine whether dynamic ABC (Aesculap, Tuttlingen, Germany) plates would minimize major complications (plate/graft extrusion, pseudarthrosis) while maximizing neurological outcomes in 40 consecutive patients undergoing simultaneous multilevel ACF/PF with halo application.

SETTING

USA.

METHODS

Patients averaged 53 years of age and preoperatively exhibited severe myeloradiculopathy (Nurick Grade 3.9). MR/CT studies documented marked ossification of the posterior longitudinal ligament/spondylostenosis. Surgery included two to four level ACF utilizing fibula strut allograft and ABC plates. Posterior spinous process wiring/fusions utilized braided titanium cables. The average operative time was 8.9 h. Fusion was confirmed on dynamic X-rays/CTs (3-12 months postoperatively). The average follow-up interval was 2.7 years. Outcomes (3 months-2 years postoperatively) were assessed utilizing Odom's Criteria, Nurick Grades, and SF-36 questionnaires.

RESULTS

Major complications included one pseudarthrosis requiring secondary PWF. Minor complications in six patients included two pulmonary emboli (PE), two tracheostomies, and five superficial wound infections. At 1 year postoperatively, marked improvement was observed in all patients utilizing Odom's criteria (38 excellent/good), Nurick Grades (mild radiculopathy 0.4), and the SF-36 (3 Health Scales; Role Physical (12.5-38.6), Bodily Pain (39.9-65.5), and Role Emotional (53.8-75.8)]. The 2-year postoperative data showed minimal additional improvement. The average time to fusion was 6.3 months.

CONCLUSION

Patients undergoing multilevel ACF/PF demonstrated marked neurological improvement (SF-36), and only one of 40 developed a delayed pseudarthrosis.

Cervical cord compression secondary to ossification of the posterior longitudinal ligament

STUDY DESIGN

Resident's case problem.

BACKGROUND

A 52-year-old Chinese male with a 10-year history of gradually worsening right hip stiffness, weakness, and pain was referred to physical therapy by his orthopedist, who made a diagnosis of developmental dysplasia of the right hip, with possible Legg-Calve-Perthes disease. The patient reported multiple falls over the last several years and a gradual onset of low back pain with an onset of "electricity" down both legs. The patient also reported mild numbness in both forearms and the right hand over the previous several months. This resident's case problem illustrates how a physical therapist recognized the presence of an atypical musculoskeletal pathology through the use of hypothesis-driven clinical reasoning and detailed physical examination.

DIAGNOSIS

Examination of the patient's lumbar and cervical spine and hips revealed joint dysfunctions. Neurological testing revealed hyperreflexia. Special testing revealed lower extremity clonus with a positive Babinski sign with gait disturbances. The patient was referred back to his primary physician and then to a neurologist and neurosurgeon. An MRI revealed cervical myelopathy due to ossification of the posterior longitudinal ligament from C3/C4 to C5/C6. The patient then underwent a C3 through C7 laminectomy.

DISCUSSION

It is always imperative that sound clinical reasoning be used when performing physical therapy evaluations, regardless of the referral status of the patient. Patients with nonmusculoskeletal pathology may seek physical therapy services and it is the physical therapist's responsibility to complete a thorough examination and refer to specialists when appropriate.