Design of the PROCON trial: a prospective, randomized multi – center study comparing cervical anterior discectomy without fusion, with fusion or with arthroplasty

BACKGROUND: PROCON was designed to assess the clinical outcome, development of adjacent disc disease and costs of cervical anterior discectomy without fusion, with fusion using a stand alone cage and implantation of a Bryan's disc prosthesis. Description of rationale and design of PROCON trial and discussion of its strengths and limitations. METHODS/DESIGN: Since proof justifying the use of implants or arthroplasty after cervical anterior discectomy is lacking, PROCON was designed. PROCON is a multicenter, randomized controlled trial comparing cervical anterior discectomy without fusion, with fusion with a stand alone cage or with implantation of a disc. The study population will be enrolled from patients with a single level cervical disc disease without myelopathic signs. Each treatment arm will need 90 patients. The patients will be followed for a minimum of five years, with visits scheduled at 6 weeks, 3 months, 12 months, and then yearly. At one year postoperatively, clinical outcome and self reported outcomes will be evaluated. At five years, the development of adjacent disc disease will be investigated. DISCUSSION: The results of this study will contribute to the discussion whether additional fusion or arthroplasty is needed and cost effective. TRIAL REGISTRATION: Current Controlled Trials ISRCTN4168184

Substantial clinical benefit for Neck Disability Index revisited: establishing the goal for treatment?

Contains fulltext : 192293.pdf (publisher's version ) (Open Access

Self-rated evaluation of outcome of the implantation of interspinous process distraction (X-Stop) for neurogenic claudication

The treatment of lumbar spinal stenosis is either conservative or surgical decompression. Recently, an interspinous decompression device (X-Stop) has been developed as an alternative. Patients treated with an X-Stop between 2003 and 2006 are subject of this study. The SF-36 Health Survey and Zürich Questionnaires are used. The data of pre- and post-operative self-rated questionnaires are collected and analysed by independent investigators. The data were statistically analysed. A good outcome was defined when the mean score at the ZQ for satisfaction was at maximal 2.0, and the mean improvement of the severity score was at least 0.5, and also for vitality score. For relations between outcome and gender, smoking, BMI, orthopaedic co-morbidity, number of implanted X-Stops were sought. The change in SF-36 scales was related to the outcome. Sixty-five patients did undergo implantation of an X-Stop. The mean age was 64.4 ± 10.0 years (range: 37.0–85.0 years). 31.1% Of the patients had a good outcome. A good outcome was not related to smoking, BMI, number of implanted X-Stops. However, a good outcome was related to the absence of orthopaedic co-morbidity or male gender. Patients with a good outcome had significantly a better improvement of the scales of the SF-36 concerning physical pain or impairment. The X-Stop does improve the clinical situation. However, a good outcome is achieved less often than previously reported. Probable explanations are discussed

An assessment of the most reliable method to estimate the sagittal alignment of the cervical spine: Analysis of a prospective cohort of 138 cases

OBJECTIVE: Although there is increasing recognition of the importance of cervical spinal sagittal balance, there is a lack of consensus as to the optimal method to accurately assess the cervical sagittal alignment. Cervical alignment is important for surgical decision making. Sagittal balance of the cervical spine is generally assessed using one of two methods; namely, measuring the angle between C-2 and C-7, and drawing a line between C-2 and C-7. Here, the best method to assess sagittal alignment of the cervical spine is investigated. METHODS: Data from 138 patients enrolled in a randomized controlled trial (Procon) were analyzed. Two investigators independently measured the angle between C-2 and C-7 by using Harrison's posterior tangent method, and also estimated the shape of the sagittal curve by using a modified Toyama method. The mean angles of each quantitative assessment of the sagittal alignment were calculated and the results were compared. The interrater reliability for both methods was estimated using Cronbach's alpha. RESULTS: For both methods the interrater reliability was high: for the posterior tangent method it was 0.907 and for the modified Toyama technique it was 0.984. For a lordotic cervical spine, defined by the modified Toyama method, the mean angle (defined by Harrison's posterior tangent method) was 23.4° ± 9.9° (range 0.4°-52.4°), for a kyphotic cervical spine it was -2.2° ± 9.2° (range -16.1° to 16.9°), and for a straight cervical spine it was 10.5° ± 8.2° (range -11° to 36°). CONCLUSIONS: An absolute measurement of the angle between C-2 and C-7 does not unequivocally define the sagittal cervical alignment. As can be seen from the minimum and maximum values, even a positive angle between C-2 and C-7 could be present in a kyphotic spine. For this purpose, the modified Toyama method (drawing a line from the posterior inferior part of the vertebral body of C-2 to the posterior upper part of the vertebral body of C-7 without any measurements) is a better tool for a global assessment of cervical sagittal alignment

The trochlea is medialized by total knee arthroplasty: an intraoperative assessment in 61 patients.

Contains fulltext : 52742.pdf (publisher's version ) (Open Access)BACKGROUND: A medialization of the femoral component in a total knee arthroplasty (TKA) causes abnormal patellar tracking, which could result in patellar instability, pain, wear, and failure. Previous reports defined medialization in relation to the neutral position of the femoral component, but omitted to compare it to the anatomical position of the trochlea. We assessed intraoperatively whether there is a systematic error of the position of the prosthetic groove relative to the anatomical trochlea. MATERIAL AND METHODS: A special instrument was developed to measure consecutively the mediolateral position of the anatomical trochlea and the mediolateral position of the prosthetic groove. 3 experienced knee surgeons determined the mediolateral error of the prosthetic groove in primary TKAs in 61 patients. RESULTS: There was a significant medial error of the prosthetic groove relative to the preoperative position of the trochlea, with a mean medial error of 2.5 mm (SD 3.3) INTERPRETATION: Our findings indicate that the trochlea is medialized by TKA. Because a conscious medialization of the femoral component in a TKA produces abnormal patellar tracking patterns, further investigations will be needed to analyze the clinical consequences of this medialization of the trochlea

NDI with 95%CI at different follow-up moments for the complete sample.

<p>NDI with 95%CI at different follow-up moments for the complete sample.</p

Baseline characteristics of included patients allocated to anterior cervical discectomy without any implant (ACD), anterior cervical discectomy with fusion by cage stand-alone (ACDF), or anterior cervical discectomy with arthroplasty (ACDA) (All characteristics were similar between groups without reaching statistical significance for any difference).

<p>Numerical data represented as mean ± SD.</p

NDI with 95% CI at each follow-up moment and per treatment modality.

<p>NDI with 95% CI at each follow-up moment and per treatment modality.</p

What’s the best surgical treatment for patients with cervical radiculopathy due to single-level degenerative disease? A randomized controlled trial

<div><p>Background</p><p>To investigate the efficacy of adding supplemental fusion or arthroplasty after cervical anterior discectomy for symptomatic mono-level cervical degenerative disease (radiculopathy), which has not been substantiated in controlled trials until now.</p><p>Methods</p><p>A randomized controlled trial is reported with 9 years follow up comparing anterior cervical anterior discectomy without fusion, with fusion by cage standalone, or with disc prosthesis. Patients suffering from symptomatic cervical disk degeneration at one level referred to spinal sections of department of neurosurgery or orthopedic surgery of a large general hospital with educational facilities were eligible. Neck Disability Index (NDI), McGill Pain Questionnaire Dutch language version (MPQ-DLV), physical-component summary (PCS), and mental-component summary (MCS) of the 36-item Short-Form Health Survey (SF-36), and re operation rate were evaluated.</p><p>Findings</p><p>142 patients between 18 and 55 years were allocated. The median follow-up was 8.9±1.9 years (5.6 to 12.2 years). The response rate at last follow-up was 98.5%. NDI at the last follow-up did not differ between the three treatment groups, nor did the secondary outcomes as MPQ-DLV and PCS or MCS from SF-36. The major improvement occurred within the first 6 weeks after surgery. Afterward, it remained stable. Eleven patients underwent surgery for recurrent symptoms and signs due to nerve root compression at the index or adjacent level.</p><p>Conclusions</p><p>This randomized trial could not detect a difference between three surgical modalities for treating a single-level degenerative disk disease. Anterior cervical discectomy without implant seems to be similar to anterior cervical discectomy with fusion by cage stand-alone or with disk prosthesis. Due to the small study sample size, this statement should be considered as inconclusive so far.</p><p>Trial registration</p><p><a href="http://www.isrctn.com/ISRCTN41681847" target="_blank">ISRCTN41681847</a></p></div