Introduction: Spinal fusions have been shown to be useful in correcting spinal deformities resulting from degenerative disc disease. We sought to produce a prospective analysis of functional outcomes following lumbar spinal fusion surgery for degenerative spondylolisthesis or degenerative scoliosis secondary to degenerative disc disease. We present the interim results from our case cohort of 74 patients.

Methods: Over a period of 3 years (2005–2007), all patients who presented to this private practice with symptoms of canal stenosis or radicular pain secondary to degenerative spondylolisthesis or degenerative scoliosis were offered decompressive laminectomy and posterior lumbar interbody fusion (PLIF) surgery with interbody cages, pedicle screw instrumentation, bone morphogenic protein (BMP) and bicalcium phosphate (BCP). Patients who presented only with low back pain and did not have radicular pain or neurogenic claudication were excluded from this study. All patients who were offered spinal fusion surgery were consecutively offered the opportunity to enrol in this functional cohort analysis. Those patients who consented were prospectively entered into this functional analysis and were asked to complete Oswestry and SF-36 function questionnaires preoperatively and post-operatively. Post-operative data has been collected in some cases up to 16 months postoperatively. Patients were also assessed post-operatively by the surgeon and given an Odom clinical assessment score. Complications were also collated.

Results: 102 patients were offered surgery with 18 patients not consenting to participate in this study. Of the 84 patients who consented to participate in this study, 10 patients failed to submit both pre-operative and postoperative questionnaires, leaving 74 patients who were followed for a median 7 months (range of 1.5–16 months). There were 30 males and 44 females in the study with a median age of 73 (range 46–89). Of these 74 patients, 63 had degenerative spondylolisthesis and 11 had degenerative scoliosis. 52 patients had sufficient follow-up to assess bony fusion, of which 1 patient failed to fuse. 32 of the patients who fused reported to have improved, but 16 did not and the remainder did not submit both pre-operative and post-operative questionnaires. For the SF-36 questionnaire, the median pre-operative SF-36 score was 30 (96.6% CI 26–35) and the median post-operative SF-36 score was 48 (95.3% CI 42–56). The mean difference between the preoperative and post-operative SF-36 scores was 14 (95% CI 11–18) (p< 0.0001. The median preoperative Oswestry score was 46 (96.6% CI 42–50) and the median post-operative Oswestry score was 30 (96.6% CI 24–40) and the median post-operative Oswestry score was 30 (96.6% CI 24–40). The mean difference between the preoperative and post-operative Oswestry scores was 14 (95% CI 10–19) (p= 0.0001). 45 patients (61%) reported improvements of greater than 20 between their pre-operative and post-operative scores in either their SF-36 or Oswestry questionnaires. Of these 45 patients, 40 (89%) were also given moderate or good Odom (clinical) scores. 29 patients (39%) reported that they had not experienced improvement in their symptoms based on either their SF-36 or Oswestry questionnaires, with 12 (41%) of those 29 patients scoring poorly on their Odom scores. In all, there were 18 complications ranging from wound collections (4) and breakdowns (2) to repositioning of screws (6) and nerve root injury (2), to DVT (1) and transfusion (3).

Discussion: Interim results suggest that most patients undergoing PLIF and pedicle screw surgery with decompressive laminectomy for treatment of degenerative spondylolisthesis and degenerative scoliosis report significant improvements in function which correlate fairly well with clinical assessments performed by the surgeon at pre-operative and post-operative reviews. IInterestingly, patients generally reported either significant improvements (rather than borderline improvements) or that they had not improved at all, and that those who did report significant improvements also generally scored well on their Odom assessments. These reported improvements currently seem to be independent of whether bony fusion is achieved or not, as 16 of the 29 patients who did not report improvement actually achieved fusion. This is not unexpected as the initial PLIF procedure provides initial pre-fusion in situ rigid internal fixation.

Introduction The use of unconstrained artificial cervical disc replacement (specifically the Bryan ® prosthesis) allows maintenance of normal cervical motion (unlike conventional fusion techniques) with the goal of alleviating neck and arm pain associated with spondylotic radiculopathy.

As a relatively new technique, there is little in the literature regarding patient satisfaction with this device and there are no long term trials defining the most appropriate indication for this device nor benefits over alternative and more conventional procedures such as discectomy and fusion. This study aimed to quantify the degree of disability and functional limitation in patients selected for Bryan disc replacement both pre-operatively and from 3 months post-operatively.

Methods The Oswestry Disability Index (ODI) and the SF36 Index were both used, being robust and reproducible tools in this setting. Patients completed questionnaires pre-operatively and from 3 months post-operatively. From 1 to 3 Bryan disc prostheses were implanted in the cervical spine at each operation. Post-operative index scores were compared with the pre-operative scores for 45 patients who completed all questionnaires, from a total of 47 operated patients in one practice (97% response, 69 total implants).

Results Patients reported a decrease in measured disability and an increase in general functioning and wellbeing after Bryan cervical disc replacement. Where 100% represents total and complete disability, the mean ODI improved from 43.65% pre-operatively (95% confidence interval 37.9 – 49.4) to 19.4% (14.0 – 24.9) post-operatively. Where 100% represents full and limitless functioning, the mean SF36 improved from 42.7% pre-operatively (36.7 – 48.6) to 64.9% (57.7 – 72.0) post-operatively. All the results were significant (p value < 0.05).

Discussion After single and multiple level Bryan cervical disc replacements in the cervical spine, there is significant decrease in perceived disability and pain as well as improvement in functional ability when compared to the pre-operative status of these patients. It is proposed that if undertaking cervical discectomy, maintenance of normal cervical motion where possible correlates with higher patient satisfaction when compared to more conventional cervical discectomy techniques.

Introduction: This is a prospective study to determine the effectiveness of artificial disc replacements in the treatment of discogenic low back pain. There has been increasing interest in the possibility of preserving the motion of a diseased vertebral motion segment by various biomechanical designs. Preserving the motion of the segment, rather than opting for arthrodesis seems intuitively to be a more favourable treatment for several spine disorders.

Up until now most spine surgery has been salvage (correcting the effects of trauma, stabilising correcting deformity, fusing degenerative segments) not restoration of normal function. As new alternatives to fusion come to fruition, we now have the ability to truly restore the spine to normal function. Spinal arthroplasty is a new concept and includes total disc replacement, nuclear replacement and there are efforts by investigators looking at posterior element reconstruction or facet replacement.

Methods: The data have been collected from the surgical experience of one surgeon since commencement of this procedure in 1996. Data were collected from pre-operative, post-operative clinical and patient questionnaires (both pre- and post-operative) and radiological assessment.Patient questionnaires include Roland-Morris Questionnaire, Oswestry Questionnaire, Visual Analogue Scores, and SF36 Data.

Results: 86 Patients have had implantation of the Charite artificial disc prosthesis “Link”; 113 levels have been instrumented; 42 males, 44 females; follow-up two months to five years, average follow-up 20 months.

The results so far indicate good to excellent in 84% of cases. Complications have the potential to be catastrophic but attention to surgical detail results in minimal complications which will be discussed in the body of the presentation.

Discussion: This paper is a prospective study. It also represents a personal surgical evolution and understanding of the role disc replacement plays in the treatment of discogenic low back pain. Disc replacement should be used as part of the armamentarium a spine surgeon can utilise in his practice. There are strict guidelines and criteria that need to be adhered to if optimal results are to be obtained. The artificial disc which has been most extensively used in the world is the Link SB Intervertebral Prosthesis. To date, over 2000 cases have been performed worldwide. The study is not intended to suggest that routine or indiscriminate use of the artificial disc replacement is warranted, but rather serves to provide a framework for further investigation to the utility of spinal arthroplasty with function intervertebral replacements.

Introduction: Anterior cervical discectomy and inter-body fusion (ACDF) is recognised as an effective surgical treatment for cervical degenerative disc disease. The goals of anterior discectomy, interbody graft placement, and subsequent fusion, are to improve and maintain intervertebral height, establish and maintain physiological cervical lordosis, and achieve arthrodesis so as to eliminate pathological motion. Establishing the most clinically effective and cost effective operative approach to achieve these goals while, at the same time, minimising post-operative complications, is currently an evolving process. One view is that the use of anterior cervical plates reduces graft-related complications, maintains the cervical alignment, and leads to a higher incidence of fusion. In addition, there is evidence to suggest that there is a direct cost benefit of earlier return to pre-operative function and employment.

Bone graft: Iliac crest autograft would be regarded as the gold standard source of bone for ACDF. However, donor site complications (due to harvesting autograft) are not insignificant and range from 1% to a sizeable 29%. These complications include iliac crest fracture, infection, persisting pain, neural injury, bowel injury, etc. With the advent of bone banks, allograft has become available and eliminates the problem of graft-harvest related complications. There is a theoretical risk of disease transmission and a corresponding difficulty with patients accepting donated tissue. To date, no HIV cases transmission has occurred from ACDF allograft. There are several studies that demonstrate a significant difference in fusion rates when comparing allograft and autograft. The preponderance of data from the literature supports the conclusion that the use of allograft in ACDF can lead to a higher incidence of graft collapse, pseudarthrosis, and possible subsequent revision surgery. Bishop et al., (Spine 1991 16:726–9): have documented a higher increase in pseudarthrosis rate, graft collapse, and interspace angulation in the allograft group compared to the autograft group. Therefore, the dilemma of allograft being preferred as a basis of eliminating graft harvesting complications, while at the same time being associated with a higher incidence of fusion failure and deformity, have led some surgeons to trial the combination of allograft with anterior plate fixation. Shapiro (J Neurosurg 1966 84:161–5) has reported no incidences of fusion failure, graft collapse, progressive kyphosis, or plate-related complications in 82 consecutive single and multiple level ACDF’s using allograft and anterior plating.

Treatment failure: The incidence of the following complications have been reported in the literature. (Graham JJ. Spine 1989 14:1046–50).

Pseudarthrosis – 3%–36%

These figures are regardless of the graft source and are significant. Recent studies show that the combination of graft and anterior plate fixation virtually eliminates the complication of graft extrusion, and also decreases the risk of graft collapse and development of pseudarthrosis. There are also studies that contend that plate fixation can maintain proper lordotic alignment of the spine more effectively than can ACDF without plating. I contend that the use of contemporary cervical plates significantly decreases the rate of fusion failure and graft-related complications without imparting significant implant-related complications.

As a result, there is decreased overall risk to the patient.

The current type of plates which are available are unicortical with locking systems that substantially decrease the risk of screw loosening or hardware migration.