Sub-optimal positioning of the implant is thought to be related to poor outcome after Lumbar Disc Replacement. Our aim was to analyse the impact of implant position in the outcome of Charite III Disc Replacement implants.

160 Charite III Lumbar Disc Replacements that were implanted between 1990 and 2000. The average age was 46 years with 62 Males and 98 Female subjects. An independent observer (HN) administered Pain score (VAS 1–10) for Low Back Pain (LBP) and Oswestry Disability Index (ODI). These clinical outcome parameters were compared with coronal and sagittal position of the implants from the latest available radiographs. Those with operation at L3L4 (small numbers = 20) and inadequate radiographs were excluded.

48 implants were optimally placed and 70 implants were placed sub optimally. Both the groups were in similar age groups (45.02 years, SD 7.61 and 48.31 years, SD 8.04). Clinical: No statistical or clinically significant difference was observed in LBP on VAS (4.92 V/S 4.41), ODI (42.8 V/S 38.0) and in Patient Satisfaction at an average follow up of 70 months. Average movement at optimally placed discs at L4L5 was 4.4o(95% CI 2.3 – 6.7) and at L5S1 was 5.9o(95% CI 4.2 – 7.5) and at sub optimally placed disc at L4L5 was 3.8o(95% CI 2.4 – 5.1) and at L5S1 was 3.8o(95% CI 2.3 – 5.3).

Clinical and radiological results after Charite III Disc Replacement is NOT dependent on positioning of implants. Movements at optimally placed implants are better but is of questionable clinical relevance.

Aim: To analyse the impact of implant position in the outcome of Charite III Disc Replacement implants.

Methodology: 160 Charite III Lumbar Disc Replacements that were implanted between 1990 and 2000. The average age was 46 years with 62 Males and 98 Female subjects. An independent observer (HN) administered Pain score (VAS 1–10) for Low Back Pain (LBP) and Oswestry Disability Index (ODI). These clinical outcome parameters were compared with coronal and sagittal position of the implants from the latest available radiographs. Those with operation at L3L4 (small numbers = 20) and inadequate radiographs were excluded.

Results: 48 implants were optimally placed and 70 implants were placed sub optimally. Both the groups were in similar age groups (45.02 years, SD 7.61 and 48.31 years, SD 8.04). Clinical: No statistical or clinically significant difference was observed in LBP on VAS (4.92 V/S 4.41), ODI (42.8 V/S 38.0) and in Patient Satisfaction at an average follow up of 70 months. Movements: Average movement at optimally placed discs at L4L5 was 4.4o(95% CI 2.3–6.7) and at L5S1 was 5.9o(95% CI4.2–7.5) and at sub optimally placed disc at L4L5 was 3.8o(95% CI 2.4–5.1) and at L5S1 was 3.8o(95%CI 2.3–5.3).

Conclusions: Clinical and radiological results after Charite III Disc Replacement is NOT dependent on positioning of implants.

Ethics approval: None

Interest Statement: None

Audit is an important part of surgical practice. Commissioners may use it as evidence of quality assurance. No comprehensive audit exists in spinal surgery. Usage of existing databases is disappointing. We developed an audit database which was comprehensive and gathered patient outcomes. The underlying principles were:

All patients having surgery should enter,

Demographic data, OPCS codes, length of stay and other data were downloaded directly from the hospital information systems. A monthly printout of patients enrolled was provided to the audit coordinator. She was responsible for the collection of clinical outcomes at 6 months, 12 months, and 2 years after surgery. The initial audit involved the Northwest and Mersey Regions. Data from the hospital information systems (HIS) for two years were available for comparison. Unfortunately only two centres gathered clinical outcomes. We have continued to gather data. 380 patients have been enrolled. HIS data are available for all. With varying lengths of follow up, there are 1045 potential clinical outcomes available. Only 8 patients (2%; 8 outcomes, 0.76%) have been lost to follow up. Using this data we are able to compare outcomes between surgeons, between surgical procedures, and see changes over time. As far as we know we are the only centre in the UK able to do this. It is a valuable Clinical Governance tool. We believe that the principles underlying this audit are the only means to obtain comprehensive outcome audit in surgery.

Introduction: Disc Replacement has been described as 21st Century revolution in spinal surgery that preserves mobility and prevents adjacent segment degeneration. Numerous short-term studies are available on clinical outcome but to date there are no published long term clinical, radiological and survival data on disc replacement.

Aim: To analyse clinical, radiological & survival results of Charite III Disc Replacement.

Study Design: Ethical committee approved retrospective study.

Methodology: 160 patients (Av. Age 46yrs; Std.Dev 8.06; 62 Males & 98 Females) underwent disc replacement surgery between Jan1990 and Dec2000. An independent observer reviewed case notes, radiographs and administered a questionnaire that included Oswestry Disability Index, and Pain Score.

Results: Clinical: At an average follow up of 79 (range 31 to 161) months, mean improvement in ODI and pain score were 18.01(p< 0.001) and 1.69(p< 0.001) respectively.

Radiological: average movement at replaced disc, defined as greater than 4 degrees on flexion-extension lateral view was 1.5 degrees for L3L4, 4.01 degrees for L4L5 and 4.8 degrees for L5S1 disc replacement.

Survival: A mean survival time of 147(95% C.I. 140 to 154) months was observed with cumulative survival of 55% with implant removal as an endpoint. A mean survival time of 124(95% C.I. 116 to 133) months with cumulative survival of 35% was observed with all radiological failures as an endpoint.

Complications: were post-operative incisional hernia seen in 17(10.6%), wound infection 9(5.6%) and retrograde ejaculation in 5(3.1%) patients.

Conclusion: Charite III Disc Replacement results in clinically significant (> 15, p< 0.001) improvement in ODI, but does not result in clinical significant (> 2 points) improvement in back pain. Motion is preserved at L4L5 and L5S1 level. It has low survival rate and does not seem to prevent onset of facet arthritis. This study does not support the use of this device for management of back pain.

Study Design: Case report of four consecutive case reports of revision surgery for anterior dislocation of the Acroflex disc (DePuy Acromed, MA, USA) all of whom required vascular surgery are described.

Objective: To describe vascular complications of explanting an artificial inter-vertebral disc replacement following spontaneous anterior displacement.

Subjects: Four consecutive patients required explantation of the Acroflex disc. Two patients were male and two female with median age 44 years (range 33–51). All patients gave informed consent to enter a clinical trial, which had ethical approval.

Outcome measures: Symptom relief, vascular injury and deep vein thrombosis.

Results: All patients gained good symptomatic relief following disc replacement. Four patients suffered anterior displacement of the disc with a deterioration in symptoms during the 1^st year. Three suffered vascular damage to the iliac vessels. In two cases division and re-anastomosis of the iliac vein was required to allow disc removal. Ilio-femoral deep vein thrombosis occurred pre-operatively in one patient and post-operatively in a second, no deaths occurred.

Conclusions: Anterior intervertebral disc displacement is associated with vascular injury. Preventing anterior disc displacement must form an essential part of disc design with (i) rapid fixation to bone and (ii) a failsafe design to prevent local damage in case of failure. In the case of displacement, disc removal should be planned and performed with a vascular surgeon.

Aim: To analyse clinical, radiological & survival results of Charite III Disc Replacement.

Study Design: Ethical committee approved retrospective study.

Methodology: 160 patients (Av. Age 46yrs; Std.Dev 8.06; 62 Males & 98 Females) who underwent disc replacement surgery through transperitoneal approach using a midline incision, between Jan1990 and Dec2000 were identified from hospital records. An independent observer administered Oswestry Disability Index, Pain Score by telephone at the time of review (Aug2003) and reviewed Clinical and radiographic features that were recorded in pre designed form.

Results: Clinical: At an average follow up of 79 (range 31 to 161) months, mean improvement in ODI and pain score were 18.01(p< 0.001) and 1.69(p< 0.001) respectively. Radiological: Movement between the disc spaces, defined as greater than 4 degree on flexion-extension lateral view was preserved after surgery at L4L5 (4.01 degree) & L5S1(4.8 degree) level but not at L3L4( 1.5 degree) level. Average disc height was 19.7mm, and gross radiological loosening was observed after 04, Facet osteoarthritis after 65 and Heterotrophic ossification after 23 operations. Survival: Kaplan-Meier survival analysis showed mean survival time of 147(95% C.I. 140 to 154) months with cumulative survival of 55% at 156 months with implant removal as an endpoint. A mean survival time of 124(95% C.I. 116 to 133) months with cumulative survival of 35% was observed with all radiological failures as an endpoint. Complications: Commonest complication was post-operative incisional hernia seen in 17(10.6%) patients. Other complications were: post-operative ileus 4(2.5%), wound infection 9(5.6%) and retrograde ejaculation in 5(3.1%) patients.

Conclusion: Charite III Disc Replacement results in a clinical significant (> 15, p< 0.001) improvement in ODI, it however does not result in clinical significant (> 2 points) improvement in back pain.Preservation of motion is of questionable clinical significance and it has low survival. Prospective studies are required to confirm the efficacy of this technique

Objective: Movement in an artificial disc would be assumed to be a necessary function of the disc. The purpose of this study was to establish whether, if any, relationship existed between movement in the artificial disc and outcome.

Subjects: 25 patients who had received an artificial disc prosthesis were assessed using radiological methods. Despite many vagaries in the measurement of X-rays, fluoroscopy was used to assess gross movement and end of flexion/extension views used to measure degrees of motion.

Outcome measures: Oswestry disability score.

Results: A very clear relationship has been established between motion in the artificial disc and outcome.

Conclusions: It is likely that spinal fusion will ultimately give way to disc replacement. Although spinal fusion has been shown in the Swedish spine series to produce good outcomes for significant numbers of patients, it remains to be seen whether the retention of motion will enhance outcome in low back pain patients. This series suggests that the retention of motion is an important component in the outcome of surgery in back pain sufferers.

Introduction: The Charite Mark 3 disc prosthesis has been used by the senior author for ten years. There has always been a question mark over the wear properties of the high density polyethylene spacer used in this prosthesis.

Methods: Ten patients who have received Charite implants, eight, nine and ten years ago were subjected to helical CT scanning. Slices at 3 mm. intervals were taken across the prosthetic levels. Fifteen prostheses were studied. Four clinicians, two of whom were radiologists and one a spinal fellow, assessed the CT scans against a standard protocol. Since the original heights of the prostheses were known, it was possible to measure prosthetic height and therefore get an estimate of wear. In addition, areas of osteolysis around the prostheses were estimated, again as a sign of wear.

Results: Remarkably little wear or wear debris was noted around the 15 prostheses.

Conclusions: Although this is a small series, it confirms that the medium-term performance of this prosthesis as far as wear is concerned is good.