Treatment of cervical disc disease using Cloward's technique. I. General results, effect of different operative methods and complications in 1,106 patients

Right Versus Left Approach to Anterior Cervical Discectomy and Fusion: An Anatomic Versus Historic Debate

The debate over the influence approach sidedness has on the risk of recurrent laryngeal nerve palsy (RLNP) following anterior cervical discectomy and fusion (ACDF) has its origins with the introduction of the procedure for radicular pain in the 1950s. The recurrent laryngeal nerves follow disparate courses in the lower neck secondary to differences in embryogenesis. Because of these differences, some authors believe a right-sided approach increases the risk of RLNP. However, modern surgical series have not shown a clear risk of RLNP with a right- versus left-sided approach. By looking at the historical context surrounding the introduction of ACDF, we propose the dogmatic view of an increased risk of RLNP with a right-sided approach likely arose from a combination of theoretical anatomic risk and the early surgical experience of a pioneer of the procedure.

Late deep cervical infection after anterior cervical discectomy and fusion: a case report and literature review

Background

Anterior cervical discectomy and fusion (ACDF) is often performed for the treatment of degenerative cervical spine. While this procedure is highly successful, 0.1–1.6% of early and late postoperative infection have been reported although the rate of late infection is very low.

Case presentation

Here, we report a case of 59-year-old male patient who developed deep cervical abscess 30 days after anterior cervical discectomy and titanium cage bone graft fusion (autologous bone) at C3/4 and C4/5. The patient did not have esophageal perforation. The abscess was managed through radical neck dissection approach with repated washing and removal of the titanium implant. Staphylococcus aureus was positively cultured from the abscess drainage, for which appropriate antibiotics including cefoxitin, vancomycin, levofloxacin, and cefoperazone were administered postoperatively. In addition, an external Hallo frame was used to support unstable cervical spine. The patient’s deep cervical infection was healed 3 months after debridement and antibiotic administration. His cervial spine was stablized 11 months after the surgery with support of external Hallo Frame.

Conclusions

This case suggested that deep cervical infection should be considered if a patient had history of ACDF even in the absence of esophageal perforation.

Influence of plate fixation on cervical height and alignment after one- or two-level anterior cervical discectomy and fusion

PURPOSE

To evaluate the efficacy of plate fixation on cervical alignment after anterior cervical discectomy and fusion (ACDF) using a stand-alone cage (ACDF-CA), compared to ACDF performed using a cage and plate fixation (ACDF-CP) and ACDF using autologous iliac bone graft and plate fixation (ACDF-AP), for the treatment of one- or two-level cervical degenerative disease. A second objective was to assess the clinical and radiological outcomes between the groups.

METHODS

A total of 247 patients underwent ACDF and were divided into three groups: those who underwent ACDF-CA (n = 76), ACDF-CP (n = 82) or ACDF-AP (n = 89). Fusion rate and time-to-fusion, global cervical and segmental angle, fused segment height, subsidence rate, and clinical outcomes, were measured using the visual analogue scale (VAS), Oswestry Neck Disability Index (NDI), and Robinson's criteria, assessed preoperatively, immediately postoperatively, and at least 24 months, postoperatively.

RESULTS

ACDF-AP was associated with the shortest mean time-to-fusion, followed by ACDF-CP and ACDF-CA. Compared to the preoperative status, the fused segment height and segmental angle increased in all groups immediately postoperatively, being well-maintained in patients who underwent ACDF-AP, while decreasing in those who underwent ACDF-CP and ACDF-CA procedures. Global cervical lordosis increased with ACDF-AP, but decreased immediately postoperatively with ACDF-CP and ACDF-CA, and at the final follow-up. Univariate analysis confirmed that a change in fused segment height was positively associated with a change in both segmental and global cervical angles. Clinical outcomes, namely VAS and NDI scores, as well as Robinson's criteria, were comparable among the three techniques.

CONCLUSIONS

Supplementation with plate fixation, especially using autologous iliac bone graft, is beneficial for maintaining the fused segment height and cervical spine curvature, as well as reducing time-to-fusion and subsidence rate.

Anterior cervical spine surgery-associated complications in a retrospective case-control study

Anterior cervical spine procedures have been associated with satisfactory outcomes. However, the occurrence of troublesome complications, although uncommon, needs to be taken into consideration. The purpose of our study was to assess the actual incidence of anterior cervical spine procedure-associated complications and identify any predisposing factors. A total of 114 patients undergoing anterior cervical procedures over a 6-year period were included in our retrospective, case-control study. The diagnosis was cervical radiculopathy, and/or myelopathy due to degenerative disc disease, cervical spondylosis, or traumatic cervical spine injury. All our participants underwent surgical treatment, and complications were recorded. The most commonly performed procedure (79%) was anterior cervical discectomy and fusion (ACDF). Fourteen patients (12.3%) underwent anterior cervical corpectomy and interbody fusion, seven (6.1%) ACDF with plating, two (1.7%) odontoid screw fixation, and one anterior removal of osteophytes for severe Forestier's disease. Mean follow-up time was 42.5 months (range, 6-78 months). The overall complication rate was 13.2%. Specifically, we encountered adjacent intervertebral disc degeneration in 2.7% of our cases, dysphagia in 1.7%, postoperative soft tissue swelling and hematoma in 1.7%, and dural penetration in 1.7%. Additionally, esophageal perforation was observed in 0.9%, aggravation of preexisting myelopathy in 0.9%, symptomatic recurrent laryngeal nerve palsy in 0.9%, mechanical failure in 0.9%, and superficial wound infection in 0.9%. In the vast majority anterior cervical spine surgery-associated complications are minor, requiring no further intervention. Awareness, early recognition, and appropriate management, are of paramount importance for improving the patients' overall functional outcome.

Late prevertebral abscess with sinus following anterior cervical corpectomy and fusion

Anterior cervical discectomy/corpectomy and fusion is performed in degenerative, traumatic and neoplastic etiologies of the cervical spine. This procedure is highly successful and associated with fewer complications. The rates of early and late postoperative infection have been reported to be between 0.1% and 1.6%, the late infections are being very rare. We report a rare case of a 30-year-old HIV negative, non-diabetic male who developed a late prevertebral cervical abscess with discharging sinus over posterior triangle of neck 3 years after an anterior cervical C6 corpectomy with fibular grafting and buttress screw fixation performed elsewhere for traumatic fracture C6 vertebra. The abscess was drained using radical neck dissection approach with complete excision of sinus track and removal of the infected implant. On culture, the organism was found to be beta-hemolytic streptococci, for which appropriate antibiotics were administered postoperatively. The sinus tract completely healed in 3 months time. Late infection as a complication of anterior cervical spine surgeries is rare and is associated with esophageal perforation, implant migration, seeding of the deep prevertebral space with oropharyngeal flora, or from surgical site/bacteremia or with Zenker's diverticulum. Few cases have been reported till date, but none have presented with a sinus tract. We present a case of delayed prevertebral abscess after cervical spine instrumentation that followed abnormal path causing sinus track to be developed in the site (the posterior triangle of the neck) other than previous incision site. Exploring both triangles of the neck using radical neck dissection approach was essential for complete excision of sinus track, removal of screw and debridement.

Wrist drop and muscle weakness of the fingers induced by an upper cervical spine anomaly

PURPOSE

This report presents a case of wrist drop and muscle weakness of the fingers as a false localizing sign induced by stenosis of the upper cervical spine caused by a bony anomaly.

METHODS

A 77-year-old male complained of severe muscle weakness of the right hand. Cervical spine MRI showed a severe and sharp compression of the spinal cord from the dorsal side between C2 and C3 with intramedullary intensity changes and mild stenosis at C3/4 and C4/5.

RESULTS

The patient underwent laminectomy of C2, cranial side laminotomy of C3, and laminectomy of C4. Decompression of the spinal cord was demonstrated 1 year after surgery. The patient achieved full recovery of the muscle weakness 1 year after undergoing surgery.

CONCLUSIONS

The pathophysiology of false localizing signs remains controversial; however, we believe that this unusual compression pattern and level had the possibility to induce atypical myelopathies such as drop hand and finger of the unilateral hand in this case.

Unusual fatal infections after anterior cervical spine surgeries

We report two cases of cervical spinal epidural abscess (SEA), which are related to anterior cervical surgeries. The first case reveals a late postoperative infection without any predisposing factor. The second case reveals combined complication of infection and instrument failure (artificial disc). Both two cases manifested ascending infections that are unusual courses of anterior cervical infections. The abscess extended upwards and, finally, caused life threatening bacterial meningitis. We suggest aggressive surgical interventions with anti-bacterial therapies in such cases.

An early comparative analysis of the use of autograft versus allograft in anterior cervical discectomy and fusion

Objective

The purpose of this study is to verify the usefulness of autograft versus allograft in the radiographic and clinical outcome in early period after the surgery.

Methods

We performed a retrospective review of 38 patients who had undergone one- or two-level anterior cervical discectomy and fusion (ACDF) with rigid anterior plate fixation from March 2006 to May 2009. Interbody graft materials were iliac autograft (n=17) or with allograft (n=21). Fusion rate and graft collapse rate were assessed by radiographic analysis and clinical outcome was based on Odom's criteria.

Results

In autograft group, 13 patients achieved successful bone fusion (65%), whereas 7 patients (31.8%) in allograft group. There was statistically significant between two groups (p<0.05). Comparing immediate postoperative radiograph with last follow-up, the mean graft collapse was noted 1.3mm(15.5% change) in autograft group, whereas 2.0mm(24.7% change) in allograft group. There was no statistically significant collapse rate in autograft group (p>0.05), but statistically significant in allograft group (p<0.05). Clinical outcome was excellent or good in 94.1% in autograft group, and 90.5% in allograft group.

Conclusion

In study, anterior cervical interbody fusion with an allograft got a result of lower fusion rate and higher collapse rate compared with autograft in early period after surgery, and clinical outcome showed similar results in both groups.

Clinically relevant anatomy of high anterior cervical approach

STUDY DESIGN

An anatomic study of anterior cervical dissection of 11 embalmed cadavers and measurement of structures relative to cervical spine.

OBJECTIVE

To determine the anatomic relationship of the hypoglossal nerve (HN), internal and external superior laryngeal nerves (ESLNs), superior thyroid artery (STA), and superior laryngeal artery (SLA) to cervical spine and demonstrate any vulnerability.

SUMMARY OF BACKGROUND DATA

The anterior approach is a common approach to the cervical spine. Much of the operative morbidity in high cervical region is related to neurovascular injury leading to dysphagia, dysphonia, impaired high-pitch phonation, and impaired cough reflex.

METHODS

Eleven adult cadavers (5 male/6 female) were dissected bilaterally to expose structures of the high anterior cervical region.

RESULTS

The HN consistently traveled toward the midline at C2-3 and was safe caudal to C3-4. In 95% of dissections, the internal superior laryngeal nerve (ISLN) was exposed within 1 cm of C3-4. The path of the ESLN was variable, but it was safe above C3-4 and below C6-7. The ESLN was deep to the STA, and it was less bulky and tauter than the ISLN in all dissections. The origin of the STA was quite variable along the carotid artery, but it was most commonly located at C4. Two anatomic variants of the SLA were observed. In 15 dissections, the SLA branched off the superior thyroid. In six dissections, the SLA branched directly from external carotid artery. There was no appreciable side-to-side variation in the neurovascular structures studied.

CONCLUSION

On the basis this study, spine surgeons can have enhanced knowledge of high anterior cervical anatomy. The neurovascular structures in this study did not demonstrate side-to-side anatomic variation; therefore, patient pathology and surgeon preference should dictate the operative side.

Single or double-level anterior interbody fusion techniques for cervical degenerative disc disease

BACKGROUND

The number of surgical techniques for decompression and solid interbody fusion as treatment for cervical spondylosis has increased rapidly, but the rationale for the choice between different techniques remains unclear.

OBJECTIVES

To determine which technique of anterior interbody fusion gives the best clinical and radiological outcomes in patients with single- or double-level degenerative disc disease of the cervical spine.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2009, issue 1), MEDLINE (1966 to May 2009), EMBASE (1980 to May 2009), BIOSIS (2004 to May 2009), and references of selected articles.

SELECTION CRITERIA

Randomised comparative studies that compared anterior cervical decompression and interbody fusion techniques for participants with chronic degenerative disc disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed risk of bias using the Cochrane Back Review Group criteria. Data on demographics, intervention details and outcome measures were extracted onto a pre-tested data extraction form.

MAIN RESULTS

Thirty-three small studies ( 2267 patients) compared different fusion techniques. The major treatments were discectomy alone, addition of an interbody fusion procedure (autograft, allograft, cement, or cage), and addition of anterior plates. Eight studies had a low risk of bias. Few studies reported on pain, therefore, at best, there was very low quality evidence of little or no difference in pain relief between the different techniques. We found moderate quality evidence for these secondary outcomes: no statistically significant difference in Odom's criteria between iliac crest autograft and a metal cage (6 studies, RR 1.11 (95% CI 0.99 to1.24)); bone graft produced more effective fusion than discectomy alone (5 studies, RR 0.22 (95% CI 0.17 to 0.48)); no statistically significant difference in complication rates between discectomy alone and iliac crest autograft (7 studies, RR 1.56 (95% CI 0.71 to 3.43)); and low quality evidence that iliac crest autograft results in better fusion than a cage (5 studies, RR 1.87 (95% CI 1.10 to 3.17)); but more complications (7 studies, RR 0.33 (95% CI 0.12 to 0.92)).

AUTHORS' CONCLUSIONS

When the working mechanism for pain relief and functional improvement is fusion of the motion segment, there is low quality evidence that iliac crest autograft appears to be the better technique. When ignoring fusion rates and looking at complication rates, a cage has a weak evidence base over iliac crest autograft, but not over discectomy alone. Future research should compare additional instrumentation such as screws, plates, and cages against discectomy with or without autograft.

Complications of Bryan cervical disc replacement

The primary goals of cervical disc replacement are to avoid fusion in the affected segment, maintain the mobility and function of the involved cervical segments, allow patients to quickly return to routine activities and reduce or eliminate adjacent-segment disease. A large number of patients have already undergone, and more and more patients will in the future undergo, cervical disc replacement. The cervical device which best preserves movement, and has therefore been the device of choice, has been the Bryan cervical disc. Although a safe surgical technique has been demonstrated and favorable results of using the Bryan disc reported, some complications have also accompanied this arthroplasty. Complications of Bryan cervical disc replacement include those related to the operative approach and decompression process, loosening and failure of the device, postoperative kyphosis, heterotopic ossification, and loss of movement due to spontaneous fusion. In order to avoid these complications, strict patient selection criteria and a meticulous knowledge of anatomy are necessary.

Submandibular approach to the C2–3 disc level: microsurgical anatomy with clinical application

Object

Approaching the C2–3 disc level is challenging because of its location behind the mandible and the vital neurovascular structures overlying the area. The purpose of this study was to illustrate in a stepwise fashion the microsurgical anatomy of the submandibular approach to the C2–3 disc.

Methods

Ten adult formalin-fixed cadaveric specimens (20 sides) were studied. Particular attention was paid to the structures limiting the exposure. The authors measured the distance between the inferior border of the mandible and the marginal mandibular branch of the facial nerve running inferior to the mandible, the distance between the horizontal segment of the hypoglossal nerve and the hyoid bone, and the distance between the horizontal segment of the hypoglossal nerve and the mandible. They compared the location of the superior laryngeal nerve with regard to the submandibular and the standard Smith-Robinson approaches. A clinical case illustrating the usefulness of the surgical technique in this region is presented.

Results

The mean distance between the inferior border of the mandible and the lowest point of the marginal mandibular branch of the facial nerve was 6.7 ± 1.69 mm. The hypoglossal nerve's mean distance above the hyoid bone was 8.4 ± 1.78 mm and below the mandible was 19.6 ± 6.39 mm. The internal branch of the superior laryngeal nerve, with respect to the cervical spine, always entered the thyrohyoid membrane just inferior to the C-3 vertebral body. The superior laryngeal nerve was found to be an impediment to approaching the C2–3 disc through the standard Smith-Robinson approach.

Conclusions

The submandibular approach provides excellent exposure, with a perpendicular view of the C2–3 disc level. This approach is one of the options to be considered when dealing with high cervical pathologies.

Bone graft substitutes in anterior cervical discectomy and fusion

Anterior cervical discectomy with fusion is a common surgical procedure for patients suffering pain and/or neurological deficits and unresponsive to conservative management. For decades, autologous bone grafted from the iliac crest has been used as a substrate for cervical arthrodesis. However patient dissatisfaction with donor site morbidity has led to the search for alternative techniques. We present a literature review examining the progress of available grafting options as assessed in human clinical trials, considering allograft-based, synthetic, factor- and cell-based technologies.

Immediate (0-6 h), early (6-72 h) and late (>72 h) complications after anterior cervical discectomy with fusion for cervical disc degeneration; discharge six hours after operation is feasible

OBJECTIVES

The introduction of minimally invasive techniques and total intravenous anaesthesia has led to reports of the performance of anterior cervical discectomy and fusion as an outpatient. The safety of this approach, requires information about the complications presenting within this period. The aim of this study was to assess the rates and types of immediate (0-6 h), early (6-72 h) and late (>72 h) complications after anterior cervical discectomy with fusion.

METHODS

We prospectively studied complications after anterior cervical discectomy with fusion in patients with degenerative cervical disc disease. There were 390 consecutive operations: 278 fused with autologous iliac crest bone graft and 112 with a PEEK (Polyetheretherketone) graft.

RESULTS

No patient died. Thirty seven patients (9%) experienced one or more complications that could be related to the operation. These presented in the immediate, early and late periods in 17, 1 and 19 patients, respectively. Thus, 18/37 complications were detected before discharge from the neurosurgical department 48-72 h after operation and of these 17 (4.2%) were detected within the first 6 h after surgery. Each of the five potentially life-threatening neck hematomas was detected within 6 h (immediate).

CONCLUSIONS

After anterior cervical discectomy and fusion, a 6 h postoperative observation period followed by discharge from the neurosurgical unit is likely to be as safe as observation as an inpatient for a longer period.

Anterior cervical discectomy and fusion associated complications

STUDY DESIGN

Retrospective review study with literature review.

OBJECTIVE

The goal of our current study is to raise awareness on complications associated with anterior cervical discectomy and fusion (ACDF) and their early detection and proper management.

SUMMARY OF BACKGROUND DATA

It is known that ACDF constitutes one of the most commonly performed spinal procedures. Its outcome is quite satisfactory in the majority of cases. However, occasional complications can become troublesome, and in rare circumstances, catastrophic. Although there are several case reports describing such complications, their rate of occurrence is generally underreported, and data regarding their exact incidence in large clinical series are lacking. Meticulous knowledge of potential intraoperative and postoperative ACDF-related complications is of paramount importance so as to avoid them whenever possible, as well as to successfully and safely manage them when they are inevitable.

METHODS

In a retrospective study, 1015 patients undergoing first-time ACDF for cervical radiculopathy and/or myelopathy due to degenerative disc disease and/or cervical spondylosis were evaluated. A standard Smith-Robinson approach was used in all our patients, while an autologous or allograft was used, with or without a plate. Operative reports, hospital and outpatient clinic charts, and radiographic studies were reviewed for procedure-related complications. Mean follow-up time was 26.4 months.

RESULTS

The mortality rate in our current series was 0.1% (1 of 1015 patients, death occurred secondary to an esophageal perforation). Our overall morbidity rate was 19.3% (196 of 1015 patients). The most common complication was the development of isolated postoperative dysphagia, which observed in 9.5% of our patients. Postoperative hematoma occurred in 5.6%, but required surgical intervention in only 2.4% of our cases. Symptomatic recurrent laryngeal nerve palsy occurred in 3.1% of our cases. Dural penetration occurred in 0.5%, esophageal perforation in 0.3%, worsening of preexisting myelopathy in 0.2%, Horner's syndrome in 0.1%, instrumentation backout in 0.1%, and superficial wound infection in 0.1% of our cases.

CONCLUSION

Meticulous knowledge of the ACDF-associated complications allows for their proper management. Postoperative dysphagia, hematoma, and recurrent laryngeal nerve palsy were the most common complications in our series. Management of complications was successful in the vast majority of our cases.

Anterolateral extradural approach for C2–C3 disc herniation: technical case report

High cervical disc herniations (C2-C3) are extremely rare, and various approaches have been used to treat C2-C3. In this report, we recommend the anterolateral extradural approach as an alternative to treat C2-C3 disc herniation. A 72-year-old woman was referred to us with severe pain in the left side of her neck and occipital region. She had been taking high doses of analgesics but had no myelopathic symptoms. Magnetic resonance imaging of the cervical spine revealed that left paramedian, extruded C2-C3 disc material was compressing the spinal cord and the left C3 nerve root. A left-sided anterolateral extradural approach was done to remove the extruded disc material at the C2-C3 level. After resection of the transverse processes of C1 and C2, the V3 segment of the vertebral artery was mobilized posteromedially. The extruded disc material was carefully removed, and the vertebral artery was freed and repositioned. The anterolateral extradural approach to a C2-C3 disc herniation is a good alternative, especially in patients with thick or short necks.

Anterior cervical discectomy and fusion: analysis of surgical outcome with and without plating

The aim of this study is to analyse the differences in clinical and radiological outcome of anterior cervical discectomy and fusion for cervical degenerative disease, with and without the addition of an anterior cervical locking plate. Although disc arthoplasty is gaining popularity, the anterior cervical decompression and fusion procedure remains the gold standard. The outcome of 242 cases operated between 1991 to 1998 were analysed. Two groups of patients were operated on by the same surgeon. The only difference in technique between the two groups was the addition of an anterior cervical plate, with all other technical details matching, including the use of iliac crest autograft. The indications for surgery for both groups was identical. We made an attempt to study radiological fusion, clinical outcome and complications between the non-plated and plated groups. Our main finding is that the addition of an anterior plate reduces the number of poor clinical outcomes, but does not increase the number of excellent outcomes. Anterior discectomy and fusion with plating in our series had a significantly higher fusion rate; 98% fusion was noted in the plating group as compared to 93.5% in the non-plating group (Fisher's exact test, p=0.029). Union was faster in the plated group with no significant increase in surgical complications. Although clinical outcomes were superior in the plated group for the radiculopathy cohort, excellent outcomes were not significantly higher as compared to the non-plated group. The non-plated group had a significantly higher rate of poor outcomes, with 10% of patients requiring revision surgery for non-union, kyphosis, graft extrusion and graft collapse with foraminal stenosis. 1.8% of the plated group required revision surgery.

Headache in patients with cervical radiculopathy: a prospective study with selective nerve root blocks in 275 patients

Since many years we routinely use diagnostic selective nerve root blocks (SNRB) at our department when evaluating patients with cervical radiculopathy. Frequently patients who also presented with headache reported that the headache disappeared when the nerve root responsible for the radicular pain was blocked with local anaesthetics. Headache has been described as a companioning symptom related to cervical radiculopathy but has never before been evaluated with SNRB performed in the lower cervical spine. For this reason we added to our routine an evaluation of the response from the SNRB on headache in patients with cervical radiculopathy. The aim was to describe the frequency of headache in patients with cervical radiculopathy and its response to a selective nerve root block of the nerve root/roots responsible for the radiculopathy. Can nerve root compression in the lower cervical spine produce headache? In this consecutive series of 275 patients with cervical radiculopathy, 161 patients reported that they also suffered from daily or recurrent headache located most often unilaterally on the same side as the radiculopathy. All patients underwent a careful clinical examination by a neurosurgeon and a MRI of the cervical spine. The significantly compressed root/roots, according to the MRI, underwent SNRB with a local anaesthetic. The effect of the nerve root block on the radiculopathy and the headache was carefully noted and evaluated by a physiotherapist using visual analogue scales (VAS) before and after the SNRB. All patients with headache had tender points in the neck/shoulder region on the affected side. Patients with headache graded significantly more limitations in daily activities and higher pain intensity in the neck/shoulder/arm than patients without headache. After selective nerve root block, 59% of the patients with headache reported 50% or more reduction of headache and of these 69% reported total relief. A significant correlation was seen between reduced headache intensity and reduced pain in the neck, shoulder and arm. The result indicates that cervical root compression from degenerative disease in the lower cervical spine producing radiculopathy might also induce headache.

Investigation of clinically important benefit of anterior cervical decompression and fusion

The objectives of the prospective randomized study are to investigate the clinically relevant change after anterior cervical decompression and fusion (ACDF) using measures of pain intensity (visual analog scale, VAS) and neck disability index (NDI). And to determine the number of subjects showing persistent pain and disability at 6-year follow-up. To investigate the possibility of differences in outcome between ACDF with the cervical intervertebral fusion cage (CIFC) and the Cloward procedure (CP). Clinically relevant change and residual, postoperative pain intensity and disability after ACDF have been investigated a little. Ninety-five patients with neck and radicular arm pain lasting for at least 6 months were randomly selected to receive ACDF with the CP or the CIFC. Questionnaires concerning pain and NDI were obtained from 83 patients (87%) at a mean follow-up time of 76 months (range 56-94 months). When evaluating clinical benefits regarding pain intensity 6 years after ACDF, according to different cut-off points and relative percentages, symptoms improved in 46-78% of patients. Improvement in NDI was seen in 18-20% of patients. Approximately 70% of the patients had persistent pain and disability at 6-year follow-up. There was no clinically important difference following CP versus CIFC. Thirty millimeter and 20% in pain intensity and NDI, respectively, are reasonable criteria to suggest a clinically relevant change after ACDF. Before patients undergo ACDF, they should be informed that they have an approximate 50% probability of achieving pain relief and little probability of functional improvement. The findings demonstrate that there is poor evidence for difference between CIFC and CP.

Long-term randomised comparison between a carbon fibre cage and the Cloward procedure in the cervical spine

A prospective randomised study. To compare the long-term outcome of anterior cervical decompression and fusion (ACDF) with a cervical intervertebral fusion cage (CIFC) and the Cloward procedure (CP). We have previously shown that the 2 year outcome of ACDF with the CIFC is the same as for the CP. The fusion rate in CIFC group was, however, only 55%, compared to 85% in CP group. The long-term outcome of CIFC is poorly documented. Ninety-five patients with at least 6 months duration of neck pain and radicular arm pain were randomly allocated for ACDF with the CIFC or the CP. Radiographs were obtained at 2 years. Questionnaires about pain, disability (Neck Disability Index, NDI), distress, quality of life and global outcome were obtained from 83 patients (87%) (43 CIFC, 40 CP) at a mean follow-up time of 6 years (range 56-94 months). There were no significant differences in any outcome variable between the two treatments. For both CP and CIFC the pain intensity improved (P<0.0001) whereas the NDI was unchanged at long-term follow-up compared to preoperatively. In the CIFC group patients with a healed fusion had significantly less mean pain (24 mm) and NDI (26%) than patients with pseudarthrosis (42 and 41, respectively). Furthermore, the mean pain and NDI reported by CIFC patients with a healed fusion was significantly less than in healed CP patients (37 and 38, respectively). The long-term outcome is the same for the CIFC and the CP, with similar improvements of pain but with considerable remaining functional disability. However, in the subgroup of patients with healed CIFC the outcome was clearly better than for the non-healed CIFC group, and also clearly better than for the healed CP group. Thus, if the healing problem associated with the CIFC can be solved the results indicate that a better outcome can be expected with the cage than with the CP.

[HAC-titanium as an implant for interbody fusion in spinal canal stenosis of the cervical spine. Six-year clinical trial]

A total of 102 patients were operated on in 134 levels because of an isolated spondylotic cervical stenosis in 6 years. A titanium implant coated with hydroxyapatite ceramic (HAC) was inserted. The average age of the patients was 53 years. The final clinical and radiological follow-up was performed after 15 months. The functional outcome was classified as good to excellent (Odoms's score) in 83.8% of the patients. Implant-related complications requiring revision surgery included two dislocated dowels and one vertebral collapse in a bisegmental operation. After 6 weeks beginning of bony growth around the implant was seen in 38% of all inserted titanium cages on roentgenograms. A complete solid bony incorporation was shown in 91.2% of the fused segments after 6 months and in 96% after 12 months or at follow-up, respectively. These results illustrate the efficacy of the easy to handle HAC titanium implant, demonstrating that this technique achieves good clinical outcome with the same complication rate as comparable techniques.

Use of the Solis cage and local autologous bone graft for anterior cervical discectomy and fusion: early technical experience

Object. The authors prospectively evaluated the clinical and radiological outcomes after anterior cervical discectomy and fusion (ACDF) involving placement of a Solis cage and local autograft in patients who presented with symptomatic cervical spondylosis.

Methods. Twenty-two consecutive patients underwent ACDF for radiculopathy (13 cases), myeloradiculopathy (eight cases), or myelopathy alone (one case) and were assessed at 3, 6, and 12 months. Plain cervical spine radiography demonstrated a significant change in both local (p < 0.05) and regional (p < 0.05) kyphotic angles as well as an increase in segmental height (p < 0.05). At 12 months, plain radiography demonstrated Grades I, II, and III new bone formation in two, three, and 17 patients, respectively. Clinical outcomes were assessed using a visual analog scale for both neck and arm pain and a modified Japanese Orthopaedic Association (JOA) scale for myelopathy. There was a significant improvement in both arm (p < 0.05) and neck pain (p < 0.05). At 12 months, 16 (84%) of 19 and 19 (86%) of 22 patients reported complete resolution of arm pain and neck pain, respectively. There was a significant improvement in JOA scores following surgery (p < 0.05). There were two complications in the series: one case of deep venous thrombosis and one case of postoperative arm pain that resolved after conservative treatment. There were no technical complications.

Conclusions. Early experience with Solis cage—augmented ACDF indicates good clinical and radiological outcomes; additionally, there are the advantages of absent donor site morbidity and anterior plate system—related morbidity.

Single or double-level anterior interbody fusion techniques for cervical degenerative disc disease

BACKGROUND

The number of surgical techniques for decompression and solid interbody fusion as a treatment for cervical spondylosis has increased rapidly, but the rationale for the choice between different techniques is unclear.

OBJECTIVES

The goal of this study was to determine which method of anterior cervical interbody fusion at a single or double-level provides the best clinical and radiological outcome in patients with degenerative disc disease.

SEARCH STRATEGY

Studies were identified with a computer-assisted search of electronic databases in the Cochrane Central Register of Controlled Trials (Issue 1, 2004), MEDLINE (1966 to 2004), EMBASE (1980 to 2004), and Current Contents (1996 to 2004). We also searched references of selected articles.

SELECTION CRITERIA

With the aid of a checklist, two reviewers independently screened the identified references. Consensus was reached through negotiation. A third reviewer was consulted if consensus could not be reached. Inclusion criteria included: articles were reports of randomised comparative studies; treatments compared anterior cervical decompression and interbody fusion techniques, participants were individuals scheduled for surgery for a chronic (longer than 12 weeks) diagnosis of degenerative disc disease.

DATA COLLECTION AND ANALYSIS

Methodological quality was assessed independently by two reviewers, using the van Tulder list of criteria. With the aid of a data extraction form, data was extracted independently by two reviewers on group characteristics, intervention details and outcome measures.

MAIN RESULTS

Fourteen studies with 939 patients evaluated three comparisons of different fusion techniques. From these comparisons it appears that discectomy alone has a shorter operation time, hospital stay, and post-operative absence from work than discectomy with fusion, while there is no statistical difference for pain relief and rate of fusion. It also appears that fusion techniques that use autograft give a better chance for fusion than interbody fusion techniques that use a cage, but other outcome variables could not be combined.

REVIEWERS' CONCLUSIONS

The low quality of the trials prohibits extensive conclusions from this review. More studies with better methodology and reporting are needed. There should be a more general agreement between researchers on which outcome parameters should be used in the evaluation of anterior cervical fusion procedures.

High cervical disc herniation presenting with C-2 radiculopathy

✓ The authors report the case of a 78-year-old man with a C2–3 disc herniation that had migrated rostrally, causing C-2 radiculopathy. The C-2 radiculopathy manifested immediately after the patient underwent placement of a ventriculoperitoneal shunt for normal-pressure hydrocephalus. Myelography and computerized tomography scanning of the cervical spine revealed an extradural lesion anterolateral to the thecal sac eccentric to the right. The patient underwent a C1–3 laminectomy, C-2 nerve root decompression, and excision of the lesion. Postoperatively the patient's radiculopathy resolved completely. To the authors' knowledge, this is the first case of a C2–3 disc herniation manifesting as C-2 radiculopathy and treated via a posterior extradural approach.

Dysphagia, hoarseness, and unilateral true vocal fold motion impairment following anterior cervical diskectomy and fusion

The charts of 100 patients who underwent anterior cervical diskectomy with fusion performed at our institution between January 1996 and February 1999 were reviewed. The incidences of hoarseness, dysphagia, and unilateral true vocal fold motion impairment were calculated. Univariate logistic regression was used to estimate the relationship of several patient and technical factors to the rates of occurrence of hoarseness and dysphagia. Patient age was found to be a significant predictor of postoperative dysphagia (p < .006), with an odds ratio of 1.113 (95% confidence limits, 1.04, 1.21) per year of age. Other factors studied were not found to be significant predictors. The overall incidence of these complications from the world literature was also calculated. The overall incidences of dysphagia, hoarseness, and unilateral true vocal fold motion impairment in the literature were calculated as 12.3%, 4.9%, and 1.4%, respectively. We conclude that dysphagia, hoarseness, and unilateral vocal fold motion impairment continue to remain significant complications of anterior cervical diskectomy with fusion. Older patients may be at higher risk for dysphagia.

Intermediate follow-up after treatment of degenerative disc disease with the Bryan Cervical Disc Prosthesis: single-level and bi-level

STUDY DESIGN

Prospective, concurrently enrolled, multicenter trials of the Bryan Cervical Disc Prosthesis (Medtronic Sofamor Danek, Memphis, TN) were conducted for the treatment of patients with single-level and two-level (bi-level) degenerative disc disease of the cervical spine.

OBJECTIVES

The studies were designed to determine whether new functional intervertebral cervical disc prosthesis can provide relief from objective neurologic symptoms and signs, improve the patient's ability to perform activities of daily living, decrease pain, and maintain stability and segmental motion.

SUMMARY OF BACKGROUND DATA

The concept of accelerated degeneration of adjacent disc levels as a consequence of increased stress caused by interbody fusion of the cervical spine has been widely postulated. Therefore, reconstruction of a failed intervertebral disc with functional disc prosthesis should offer the same benefits as fusion while simultaneously providing motion and thereby protecting the adjacent level discs from the abnormal stresses associated with fusion.

METHODS

Patients with symptomatic cervical radiculopathy and/or myelopathy underwent implantation with the Bryan prosthesis after a standard anterior cervical discectomy. At scheduled follow-up periods, the effectiveness of the device was characterized by evaluating each patient's pain, neurologic function, and radiographically measured range of motion at the implanted level.

RESULTS

Clinical success for both studies exceeded the study acceptance criteria of 85%. At 1-year follow-up, the flexion-extension range of motion per level: Discectomy and implantation of the device alleviates neurologic symptoms and signs similar to anterior cervical discectomy and fusion. Radiographic evidence supports maintenance of motion. The procedure is safe and the patients recover quickly. At least 5 years of follow-up will be needed to assess the long-term functionality of the prosthesis and protective influence on adjacent levels.

Preliminary clinical experience with the Bryan Cervical Disc Prosthesis

OBJECTIVE

The concept of accelerated degeneration of adjacent disc levels as a consequence of increased stress caused by interbody fusion of the cervical spine has been widely postulated. Therefore, reconstruction of a failed intervertebral disc with a functional disc prosthesis should offer the same benefits as fusion while simultaneously providing motion and thereby protecting the adjacent level discs from the abnormal stresses associated with fusion. This study was designed to determine whether a new, functional intervertebral cervical disc prosthesis can provide relief from objective neurological symptoms and signs, improve the patient's ability to perform activities of daily living, decrease pain, and provide stability and normal range of motion.

METHODS

We conducted a prospective, concurrently enrolled, multicenter trial of the Bryan Cervical Disc Prosthesis (Spinal Dynamics Corp., Mercer Island, WA) for the treatment of patients with single-level degenerative disc disease of the cervical spine. Patients with symptomatic cervical radiculopathy and/or myelopathy underwent implantation with the Bryan prosthesis after a standard anterior cervical discectomy. At scheduled follow-up periods, the effectiveness of the device was characterized by evaluating each patient's pain, neurological function, and range of motion at the implanted level.

RESULTS

Analysis included data regarding 60 patients at 6 months with 30 of those patients at 1 year. Clinical success at 6 months and 1 year after implantation was 86 and 90%, respectively, exceeding the study's acceptance criteria of 85%. These results compare favorably with the short-term clinical outcomes associated with anterior cervical discectomy and fusion reported in the literature. At 1 year, there was no measurable subsidence of the devices (based on a measurement detection threshold of 2 mm). Evidence of anterior and/or posterior device migration was detected in one patient and suspected in a second patient. There was no evidence of spondylotic bridging at the implanted disc space. The measured range of motion in flexion-extension, as determined by an independent radiologist, ranged from 1 to 21 degrees (mean range of motion, 9 +/- 5 degrees). No devices have been explanted or surgically revised.

CONCLUSION

Discectomy and implantation of the device alleviates neurological symptoms and signs similar to anterior cervical discectomy and fusion. Radiographic evidence supports normal range of motion. The procedure is safe and the patients recover quickly. Restrictive postoperative management is not necessary. However, only after long-term follow-up of at least 5 years will it become clear whether the device remains functional, thus confirming these early favorable results. In addition, the influence on adjacent motion segments can be assessed after at least 5 years of follow-up.

A prospective randomized comparison between the cloward procedure and a carbon fiber cage in the cervical spine: a clinical and radiologic study

STUDY DESIGN

A prospective randomized study was conducted.

OBJECTIVE

To determine whether the use of a cervical carbon fiber intervertebral fusion cage improves the outcome of anterior cervical decompression and fusion, as compared with the Cloward procedure using autograft.

SUMMARY OF BACKGROUND DATA

Despite the theoretical advantages of using intervertebral cages, including reduced donor site morbidity and prevention of graft collapse, an improved clinical outcome has not yet been documented.

METHODS

For this study, 103 patients were randomized to anterior cervical decompression and fusion with a carbon fiber intervertebral fusion cage (n = 52) or the Cloward procedure (n = 51). An independent observer quantified pain and functional disability. Fusion rate, segmental kyphosis, and disc height were assessed by radiographs.

RESULTS

During a mean follow-up period of 36 months (range, 24-72 months) for 89 patients (86%), the pain and disability were similar for both treatments. Postoperative donor site pain was significantly less in the carbon fiber intervertebral fusion cage group. The fusion rate was 86% in the Cloward procedure group and 62% in the carbon fiber intervertebral fusion cage group (P < 0.05). In the latter group, patients with pseudarthrosis reported more severe pain than fused patients (51 and 33 visual analog scores, respectively), but the difference was not significant. The segmental kyphosis was less and the disc height increased in the carbon fiber intervertebral fusion cage group, as compared with the Cloward procedure group. Disc height was not correlated with outcome. Segmental kyphosis showed a weak (r = -0.3) but significant (P < 0.05) correlation with improvement of the Cervical Spine Functional Score, but not with other outcome variables.

CONCLUSIONS

Except for reduced donor site pain, the clinical outcome for the carbon fiber intervertebral fusion cage is the same as for the Cloward procedure. Use of the cage results in a more lordotic alignment and an increased disc height, but in a higher pseudarthrosis rate than use of the Cloward procedure.

[Anterior cervical diskectomy and interbody arthrodesis using Cloward technique: retrospective study of complications and radiological results of 167 cases]

PATIENTS AND METHODS

We performed a retrospective analysis of complications and radiological results in 167 patients surgically treated, for discal or spondylotic disease of the cervical spine, with Cloward procedure. Using uni and multivariate analysis, we tried to identify risk factors that might be correlated with surgical complications or radiological results.

RESULTS

Surgical treatment was indicated for cervical radiculopathy in 68% of the patients and for myelopathy or radiculomyelopathy in the remaining 32%. The pathologic disease responsible of the symptomatology was soft disk herniation in 59% of the cases and spondylotic changes in 41%. The patients that underwent surgery because of myelopathy were one decade older, had a longer symptomatic period and presented multi-segmentary spondylotic disease with higher frequency than patients affected of radiculopathy. The most common segments operated were CS-C6 (44.3%) and C6-C7 (30.5%). Surgical mortality was 0.6% and morbidity 29.3%. Most of the complications were transient, although 4.8% of the patients developed permanent neurological deterioration.

CONCLUSIONS

Complications were most commonly seen in the group of the patients undergoing surgery because of long-lasting myelopathy with multi-segmentary spondylotic disease, in those with vascular risk factors and in those operated of more than one segment. Surgeon anatomic knowledge and experience are critical for diminishing such complications. Non-union rate was 9.6%, and another 9.6% of the patients developed post-surgical kyphosis. Both factors correlated with the need of re-operation.

Cadaveric fibula, locking plate, and allogeneic bone matrix for anterior cervical fusions after cervical discectomy for radiculopathy or myelopathy

OBJECT

The authors have previously reported that the results of using cadaveric fibula and locking plate (CF/LP) fusion following anterior cervical discectomy (ACD) for cervical spondylotic radiculopathy and myelopathy are superior to those obtained using autologous iliac crest (AIC) grafts in the short term. The long-term results of using this construct are important in substantiating this improvement. The authors report on 246 consecutive patients (54% smokers) who underwent ACD with CF/LP fusion (175 with allogeneic bone matrix [ABM]) and compare them with 111 consecutive patients in whom AIC fusions (49% smokers) were performed by the same surgeons.

METHODS

The study is a retrospective nonrandomized analysis, and chi-square statistics were used. Bone densitometric studies of AIC grafts and CF grafts were performed. A paired t-test was used for statistical analysis of the results. Disease in the group of patients undergoing CF/LP fusion included soft-disc herniation with radiculopathy in 14, soft-disc hemiation with myelopathy in seven, cervical spondylotic radiculopathy in 144, cervical spondylotic myelopathy in 75, AIC graft collapse pseudarthrosis in five, and ACD with no fusion collapse/kyphosis in one. Operations consisted of single-level CF/LP fusion in 142 patients and multilevel CF/LP fusion in 104. Perioperative complications in the CF/LP group included three cases of transient hoarseness. There were no transfusions, infections, neurological injuries, or deaths. The mean hospital length of stay was 1.2 days (28% outpatient and 66% 23-hour stay). The mean follow-up period was 60 months (range 12-94 months). Ten patients were lost to follow up after 1 year. Long-term complications included one traumatic plate fracture and one symptomatic pseudarthrosis with plate fracture. At 1 year and beyond, in 245 (99.6%) of 246 patients radiographically documented fusion with no motion at the fused level on flexion-extension films was demonstrated. There was no kyphosis, no symptomatic screw plate backout, and no CF/LP graft collapse (100% in the ABM group). In the 111 consecutive patients with AIC fusions, however, there was a 17% graft-related complication rate. There were significantly fewer graft-related complications in the CF/LP group (p < 0.001). There was no difference in neurological outcome for any of the groups. In the groups undergoing single-level ACD there was a significantly greater chance of complete relief of neck pain CF/LP fusion compared with those undergoing AIC fusion (p < 0.02). There was a significantly greater chance of AIC collapse with the passage of time compared with CF graft (p < 0.02). Time until return to work was shorter for the CF/LP group by 5 to 6 weeks (p < 0.02). There was a higher rate of radiographically documented pseudarthrosis in the AIC group (p < 0.006). The mean bone densitometry for the CF/LP group was 0.7 g/cm2, significantly greater than that of the AIC group, which was 0.2 g/cm2 (paired t-test p < 0.001).

CONCLUSIONS

When fusion is necessary following ACD, the results of CF/LP fusion are significantly superior in the first 5 years after surgery compared with those for AIC fusions. It remains to be determined if demineralized ABM has a significant effect in enhancing fusion.

Nonautologous interbody fusion materials in cervical spine surgery: how strong is the evidence to justify their use?

STUDY DESIGN

A review of the literature concerning the use of interbody fusion devices and materials in anterior cervical surgery.

OBJECTIVES

To examine the evidence supporting the use of interbody fusion devices as an alternative to autologous bone after anterior cervical discectomy.

SUMMARY OF BACKGROUND DATA

Concerns over the morbidity associated with harvesting autologous bone and the risk of transmissible infectious from allografts and xenografts have prompted the search for alternative methods of achieving interbody fusion. Several of these methods have been associated with an unacceptable rate of complications. The clinical and health economic implications of the widespread introduction of interbody fusion devices in the absence of sound evidence cannot be ignored.

METHODS

A systematic review of the literature relating to cervical interbody fusion was undertaken. Studies were assessed critically with respect to their methodology, results, and conclusions.

RESULTS

Thirty-two clinical studies and 10 laboratory studies were analyzed. Methodologic weaknesses were identified in the majority. Only four clinical reports were either randomized or blinded or involved independent assessment of their outcomes. Fewer than half of the studies included a valid statistical analysis. Radiologic evidence of fusion was limited in many cases. There was little evidence that nonautologous fusion devices offered a reduction in the length of hospital stay. Autologous bone was as effective as, or superior to, many other fusion devices. The early results of some new fusion techniques used alone or in combination showed promise.

CONCLUSIONS

There is limited evidence supporting the use of a cervical interbody fusion device in place of autologous bone. There is a need to standardize the testing of implants with good quality laboratory work preceding clinical use. Certain devices including cages, some forms of hydroxyapatite, and bone morphogenic proteins merit further study.

Femoral Ring Allograft for Anterior Cervical Interbody Fusion: Technical Note

OBJECTIVE

Cadaveric fibula with locking plate internal fixation has been reported to be associated with fewer complications and better long-term results, compared with autologous iliac crest. With the knowledge that cortically dense allografts collapse less with time, new machined femoral ring allografts were developed for anterior cervical fusion after anterior cervical discectomy. We describe the system and the technique for placement.

METHODS

The femoral ring allograft set consists of color-coded graft-sizers that correspond precisely to the size of the precut grafts. The purple set is primarily intended for petite cervical vertebral bodies; the purple sizers and grafts are 11 mm wide and 11 mm deep and vary in height from 5 to 9 mm. The green sizers and grafts are 14 mm wide and 11 mm deep and vary in height from 5 to 11 mm. The blue sizers and grafts are 14 mm wide and 14 mm deep and vary in height from 5 to 11 mm. The rostral and caudal faces of the grafts are corrugated, to improve their holding capacity in the interspace. The bone is sterilely packaged in vacuum-sealed bottles, the tops of which are color-coded and precisely labeled. The set also includes a graft holder (to facilitate insertion into the interspace), impactors, and a barrel-shaped cutting burr (to prepare the endplates for fusion).

RESULTS

After anterior cervical discectomy to treat spondylotic radiculopathy or myelopathy, a femoral ring allograft was inserted, with allogeneic demineralized bone matrix and a locking cervical plate, in 20 cases, with no complications. Use of the system decreased the operating time by an average of 10 to 15 minutes.

CONCLUSION

The femoral ring allograft system is easy to use, and there have been no complications to date. The long-term fusion rate remains to be determined.

Anterior discectomy and fusion for the management of neck pain

STUDY DESIGN

Data were collected prospectively on 38 patients who underwent anterior cervical discectomy and fusion for neck pain with no symptoms or signs of radiculopathy or myelopathy.

OBJECTIVES

To determine the changes in pain and function after anterior cervical discectomy and fusion for nonradicular neck pain.

SUMMARY OF BACKGROUND DATA

There is considerable controversy regarding the role of anterior cervical discectomy and fusion for neck pain in the absence of radiculopathy or myelopathy. Although no studies have addressed this specific and common problem, it is known that anterior cervical discectomy and fusion for radiculopathy or myelopathy may also provide relief of neck pain for many patients.

METHODS

Thirty-eight patients who underwent anterior cervical discectomy and fusion for neck pain were evaluated. Before and after surgery, the authors measured pain with a numerical rating scale, function with the Oswestry Disability Questionnaire, and final patient satisfaction. Final evaluation was done by a disinterested third party.

RESULTS

All 38 patients were available for follow-up study. Mean age was 42.4 years, and mean duration of follow-up study was 53 months. All patients had painful disc(s) proven by discography. No patients had nerve root compression. Anterior cervical discectomy and fusion was performed at one level in 21 patients, two levels in 16 patients, and three levels in one patient. The mean score on the numerical rating scale for neck pain before surgery was 8.3 (range, 3-10) versus 4.1 (range, 0-10) after surgery. This difference is significant (P < 0.001). The mean score on the Oswestry Disability Questionnaire was 57.5 (range, 0-89) before surgery versus 38.9 (range, 0-80) after surgery. This difference is significant (P < 0.001). There were 30 (79%) patients who were satisfied with their outcome, and 8 (21%) who were not satisfied. There was no statistical difference in change of pain or function between patients with worker's compensation and those with other insurance or between men and women. Twenty patients were not working because of neck pain before surgery, and 15 were not working at the time of follow-up examination.

CONCLUSION

A significant decrease in pain, a significant increase in function, and a high degree of patient satisfaction were found with anterior cervical discectomy and fusion for neck pain. Improvements were not affected by worker's compensation status or gender.

Soft cervical disc herniation. Influence of cervical spinal canal measurements on development of neurologic symptoms

STUDY DESIGN

In 100 consecutive patients who underwent surgery because of soft cervical disc herniation, the sagittal and transverse diameters, the area of the bony cervical spinal canal, the sagittal diameter of the hernia, and the minimal bony intervertebral foramen diameter were measured by computed tomography. The data were compared with measurements from a control group of 35 matched healthy individuals.

OBJECTIVES

To evaluate the relation between the severity of concurrent neurologic symptoms and the sagittal and transverse diameters, the cross-sectional area of the bony spinal canal, the sagittal diameter of the hernia, and diameter of the minimal bony intervertebral foramen in patients with soft cervical disc herniation.

SUMMARY OF BACKGROUND DATA

Traumatic injury and spondylotic changes have a far greater impact on the spinal cord and nerve roots if the sagittal diameter of the bony cervical spinal canal is small. However, in the case of soft cervical disc herniation, no computer tomographic measurements are available for sagittal and transverse diameters, cross-sectional area of the bony spinal canal, sagittal diameter of the hernia, and diameter of the minimal bony intervertebral foramen in relation to the severity of concurrent neurologic symptoms.

METHODS

Computed tomography was used to measure sagittal and transverse diameters, cross-sectional area of the bony cervical spinal canal, sagittal diameter of the hernia, and diameter of the minimal bony intervertebral foramen in 100 patients with symptomatic monosegmental cervical soft disc herniation. All patients had undergone an anterior discectomy with removal of the hernia and subsequent interbody fusion using an autologous bone graft taken from the iliac crest.

RESULTS

A mean sagittal diameter of the bony cervical spinal canal of 12.9 mm was found, indicating a certain degree of developmental stenosis. Patients with motor disturbances had a significantly smaller sagittal diameter of the bony spinal canal than did patients without motor disturbances. There was a linear correlation between the sagittal diameter of the bony cervical spinal canal and that of the hernia. The sagittal diameter, the area of the bony spinal canal, and diameter of the minimal bony intervertebral foramen were significantly smaller in patients with soft cervical disc herniation than in the control group.

CONCLUSIONS

Results from this study strongly suggest that the degree and severity of neurologic symptoms accompanying cervical soft disc herniation are inversely related to the sagittal diameter and the area of the bony cervical spinal canal. The latter area is reduced in cases of developmental stenosis or because of soft disc herniation. Moreover, patients with soft cervical disc herniation have a significantly smaller sagittal diameter of the bony spinal canal, a significantly smaller minimal bony intervertebral foramen diameter, and a significantly smaller cross-sectional area of the bony cervical canal than do healthy matched individuals.

Secondary gain influences the outcome of lumbar but not cervical disc surgery

BACKGROUND

The expectation of monetary compensation has been associated with poor outcomes in lumbar discectomy, fueling a reluctance among surgeons to treat worker's compensation cases. This issue, however, has not been investigated in patients undergoing cervical disc surgery. This study analyzes the relationship between economic forms of secondary gain and surgical outcome in a group of patients with common pay scales, retirement plans, and disability programs.

METHODS

All procedures were performed at the Portsmouth Naval Medical Center between 1993 and 1995; active duty military servicepersons who were treated for cervical radiculopathy were prospectively included. Clinical, demographic, and financial factors were analyzed to determine which were predictive for outcome. Financial data were used to create a compensation incentive (CI) which is proportional to the rank, years of service, potential disability, retirement eligibility, and base pay and reflects the monetary incentive of disability. The results of cervical surgery were compared to a previously reported companion population of patients treated for lumbar disc disease. A good outcome is defined as a return to active duty, whereas a referral for disability is considered a poor surgical result.

RESULTS

One hundred percent follow-up was obtained for 269 patients who were treated with 307 cervical operations. Only 16% (43/269) of cervical patients received disability, whereas 24.7% (86/348) of lumbar patients obtained a poor result (p = 0.0082). Although economic forms of secondary gain were not associated with outcome in cervical disease, both the position (p = 0.002) and duration of an individual's military career were significant factors (p = 0.02). Of the medical variables tested, multilevel surgery (p = 0.03) and revision operations at the same level (p = 0.03) were associated with referral for medical discharge.

CONCLUSIONS

Secondary gain in the form of economic compensation influences outcome in lumbar but not cervical disc surgery; this observation may in part account for the success of cervical surgery relative to lumbar discectomy. Social factors that are independent of the anticipation of economic compensation seem to influence the outcome of cervical disc surgery.

An unusual complication of Cloward's procedure presenting to the otolaryngologist

We present the case of a 51-year-old lady who developed a CSF leak following a Cloward's procedure (anterior cervical surgery with fusion), which settled with conservative management. Two months following the surgery she was assessed by an otolaryngologist for persistent dysphagia and a swelling in the anterior triangle of her neck. A computed tomography (CT) scan identified a fluid-filled mass displacing the trachea and communicating with the anterior cervical vertebrae, thus confirming the persistence of a CSF leak.

A prospective randomized study of anterior single-level cervical disc operations with long-term follow-up: surgical fusion is unnecessary

OBJECTIVE

After 40 years of experience with anterior cervical operations, whether to fuse is still controversial. This study seeks to answer this question.

METHODS

In this prospective randomized study, we operated on 91 patients with single-level cervical root compression using three different methods: 1) discectomy without fusion, 2) fusion with autologous bone graft, and 3) fusion with autologous bone graft plus plating.

RESULTS

After 4 years of follow-up, the radiological results indicated that complete bony union was achieved in almost all cases. A slight kyphosis developed in 62.5% of the patients who had undergone discectomy, 40% of the patients who had undergone fusion, and 44% of the patients who had undergone fusion plus plating (not significant). The clinical outcomes were good for 76% of the patients who had undergone discectomy, 82% who had undergone fusion, and 73% who had undergone fusion plus plating. The outcomes were poor in 0, 4, and 4%, respectively (not significant).

CONCLUSION

According to this study, satisfactory results can be achieved by performing simple discectomy to treat single-level cervical root compressive disease.

Elective cervical discectomy in California: postoperative in-hospital complications and their risk factors

STUDY DESIGN

A retrospective cohort study of short-term outcomes after elective cervical discectomy in California hospitals.

OBJECTIVES

To compare the frequency of elective cervical discectomy across population strata, to determine the frequency of adverse outcomes in the early postoperative period, and to identify risk factors for such outcomes.

SUMMARY OF BACKGROUND DATA

Previous cervical discectomy series have been too small to analyze risk factors for early complications, and have originated from centers that may not adequately represent the population.

METHODS

Computerized hospital discharge abstracts were obtained from the California Office of Statewide Health Planning and Development. Inclusion and exclusion criteria were applied to identify 10,416 routine discectomies at 257 hospitals in 1990-1991. Several categories of postoperative complications were identified, along with inpatient deaths, early reoperations, and nursing home transfers. Logistic regression was used to estimate the independent effects of patient characteristics on short-term outcomes.

RESULTS

After adjustment for age and gender, blacks were 51% and Hispanics were 24% as likely as whites to undergo elective cervical discectomy. Overall, 6.7% of patients had one or more reported postoperative complications: 1.8% had noninfectious surgical complications, 1.8% had infectious complications, 4.0% had other medical complications, and 0.35% had unplanned reoperations before discharge. Fourteen inpatient deaths were reported (0.13%). Congestive heart failure, alcohol/drug abuse, chronic lung disease, previous spine surgery, psychological disorders, and chronic musculoskeletal disorders were independently associated with postoperative complications. Even after adjustment, risk was higher with advancing age, higher among women than among men, and higher after posterior fusion than after discectomy without fusion.

CONCLUSIONS

The ethnic disparity in cervical discectomy rates suggests overuse among whites or underuse among minority populations. The complication rates reported here are similar to those synthesized from previous literature, except that the lower incidence of neurologic complications reflects our inability to distinguish preoperative from postoperative deficits. Important comorbidities should be identified and treated, if appropriate, before cervical spine surgery.

Cervical radiculopathy: pain, muscle weakness and sensory loss in patients with cervical radiculopathy treated with surgery, physiotherapy or cervical collar. A prospective, controlled study

This prospective, randomised study compares the efficacy of surgery, physiotherapy and cervical collar with respect to pain, motor weakness and sensory loss in 81 patients with long-lasting cervical radiculopathy corresponding to a nerve root that was significantly compressed by spondylotic encroachment, with or without an additional bulging disk, as verified by MRI or CT-myelography. Pain intensity was registered on a visual analogue scale (VAS), muscle strength was measured by a hand-held dynamometer, Vigorometer and pinchometer. Sensory loss and paraesthesia were recorded. The measurements were performed before treatment (control 1), 4 months after the start of treatment (control 2) and after a further 12 months (control 3). A healthy control group was used for comparison and to test the reliability of the muscle-strength measurements. The study found that before start of treatment the groups were uniform with respect to pain, motor weakness and sensory loss. At control 2 the surgery group reported less pain, less sensory loss and had better muscle strength, measured as the ratio of the affected side to the non-affected side, compared to the two conservative treatment groups. After a further year (control 3), there were no differences in pain intensity, sensory loss or paraesthesia between the groups. An improvement in muscle strengths, measured as the ratio of the affected to the non-affected side, was seen in the surgery group compared to the physiotherapy group in wrist extension, elbow extension, shoulder abduction and internal rotation, but there were no differences in the ratios between the collar group and the other treatment groups. With respect to absolute muscle strength of the affected sides, there were no differences at control 1. At control 2, the surgery group performed some-what better than the two other groups but at control 3 there were no differences between the groups. We conclude that pain intensity, muscle weakness and sensory loss can be expected to improve within a few months after surgery, while slow improvement with conservative treatments and recurrent symptoms in the surgery group make the 1-year results about equal.