We report the frequency of door-opening (“theatre traffic”) in orthopaedic operations at three metropolitan hospitals with different theatre policies. Published studies have correlated “theatre traffic” with airborne bacteria levels, which have been associated with raised wound infection rates.

Hospital A had one scoliosis operation and two hip replacements, Hospital B had one knee revision and one knee replacement. Hospital C had one scoliosis operation. A second scoliosis operation was performed at Hospital C after “theatre traffic” education and door signage discouraging entry.

One pair of surgeons performed the scoliosis operations and a different pair did the hips and knees.

Hospital A is private and Hospitals B and C are public.

The scoliosis operation in Hospital A (private) had an average door opening rate of 0.45/min compared to the same operation in Hospital C (public) with an average door opening rate of 1.0/min. The two hip replacements in Hospital A (private) had an average rate of 0.43/min and 0.51/min while the knee revision and knee replacement in Hospital B (public) had average rates of 0.91/min and 0.77/min respectively.

Of concern is the total number of door openings that result from this rate of “theatre traffic”. In the Hospital C (public) operation the total number of door openings equalled 140 over the course of the scoliosis operation. In Hospital B the total number of door openings for the knee revision was 169 and the knee replacement was 72. In contrast, for Hospital A (private) the total number of door openings for the scoliosis operation was 73 and the two hip replacements equalled 30 and 36.

The second study at Hospital C after staff education revealed a 35% decrease to 0.65/min.

There was a difference in “theatre traffic” between private and public hospitals for the same or similar operations. Staff education and door signage dramatically reduced “theatre traffic” in Hospital C. Surgeons and theatre staff need to be aware of “theatre traffic” and its influence on infection rates.

Anterior lumbar interbody fusion (ALIF) is an accepted surgical treatment for disabling discogenic pain. Additional posterior fixation has been advocated. This is a prospective clinic al study evaluating a stand-alone anterior fusion cage with an integrated titanium plate and four divergent locking screws.

Patients who had failed conservative management for lumbar discogenic pain were recruited into the study. All underwent diagnostic discography. Surgery was performed through an anterior retro-peritoneal approach. The fusion cage was packed with autogenous bone graft. Outcome measures included: Visual Analogue Scores (VAS), Oswestry Disability Index (ODI) and SF-36 data. Fine-cut CT was performed at one and two years post-operatively. Fusion was defined as continuous bony trabeculae joining the vertebral bodies.

Fifty levels were operated on in 39 patients with a mean age of 40.8 years (22–55). The mean operative time was less than 120 minutes, and mean blood loss less than 100 mls. Radiographic fusion at one year was 78% and 100% at two years. Two year mean VAS sc ores for back pain improved from 7.0 to 3.7 (p< 0.01) and for leg pain from 6.1 to 3.1 (p< 0.01). The mean ODI scores decreased from 50.7 to 31.7 (p< 0.01), and SF-36 (PCS) scores increased from 28.4 to 37.5 (p< 0.01). There were no major complications and no patients have required supplementary posterior fixation.

This technique is safe and is as effective as 360° fusion in achieving fusion in the management of discogenic back pain over one and two levels. This technique has the advantage of avoiding the morbidity associated with additional posterior fixation.

Introduction: Spinal arthrodesis with stainless steel implants is a common procedure to correct scoliosis however, the long-term consequences of retained implants is unclear. Raised serum metal ion levels have been widely published in arthroplasty literature with concern over possible toxic adverse effects associated with chronic exposure. We investigated serum metal ion levels in patients who had undergone instrumented spinal arthrodesis for scoliosis correction.

Methods: The study included patients who underwent posterior spinal arthrodesis using ISOLA instrumentation for scoliosis between 1998 and 2002. The minimal period of follow up was 3 years. Clinical information was available from a comprehensive Scoliosis Database, Department of Orthopaedic Surgery, Women’s and Children’ Hospital, Adelaide (WCH). Patients having post-operative complications, spinal instrumentation removed, revision surgery or additional in situ metal implants were excluded. Participants completed a questionnaire to evaluate exogenous chromium exposure. Blood samples were collected and processed by the WCH Core Laboratory. Serum levels of chromium, molybdenum, iron and ferritin were measured by Sydney South West Pathology Service. Participants with serum chromium levels outside the normal reference range underwent further analysis to evaluate chromium levels in erythrocyte haemolysate preparations (to assess the valency of abnormal chromium levels detected). Comparisons were made with two control groups; the first being individuals with scoliosis who had not undergone operative intervention and the other, “normal” unaffected volunteers. All control group participants underwent serum and erythrocyte analysis (as above). Ethics approval was obtained from the WCH Research Ethics Committee.

Results: Thirty patients (26 females and 4 males) who underwent instrumented scoliosis surgery, 10 non instrumented scoliosis patients and 10 unaffected volunteers were included in the study. Mean age of the operative group at surgery was 13.8 years (11.1–16.9) with a mean length of time from surgery of 5.8 years (3.5–8.2). In the study group, raised serum chromium levels were demonstrated in 11/30 (36.6%) of patients. Five of the 11 patients with raised chromium levels also had low levels of serum iron and/or ferritin. Erythrocyte levels of chromium were undetectable in all of the 11 (100%) patients. There did not appear to be an exogenous source of chromium exposure in any of these patients. In the non-operative control group with scoliosis, none had elevated serum chromium, iron or ferritin levels. 2/10 (20%) had high molybdenum levels. In the unaffected control group, 1/10 (10%) had raised serum chromium and molybdenum levels. Three control patients had low levels of serum iron and/or ferritin. All control participants, but one, had undetectable erythrocyte chromium levels. There was a significant difference in serum chromium levels between the study and control groups (p=0.01) with the group of patients who underwent instrumented scoliosis surgery having a greater proportion with high chromium and lower proportion with normal chromium.

Discussion: Raised serum chromium levels were detected in patients after instrumented spinal arthrodesis for scoliosis correction. This new finding in young patients has relatively unknown health implications but potential genotoxic and carcinogenic sequelae; this is especially concerning with most scoliosis patients being female and with their reproductive years ahead. These findings should prompt further research in this area, particularly to similarly investigate other spinal implant systems and assess the long term implications of raised chromium levels.

Introduction: Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but there are no published randomized controlled trials assessing efficacy against a placebo group.

Methods: Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed conservative treatment were considered for the study. Inclusion criteria included one or two level symptomatic internal disc disruption as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or had had previous back surgery. Fifty-seven patients were randomized with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham (placebo). The IDET catheter was positioned under sedation to cover at least 75% of the annular tear as defined by the CT/discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Surgeon, patient and independent outcome assessor were all blinded. All patients followed a standard rehabilitation programme.

Outcome Measures: Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and 6 months. Successful outcome was defined as: No neurological deficit resulting from the procedure, improvement > 7 points in LBOS, improvements > 7 points in SF-36 subsets (pain / disability, physical functioning and bodily pain)

Results: Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and worker’s compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups. No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or the specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at 6 months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the Placebo group. There was no significant change in ZDI or MSPQ scores for either group.

Discussion: No subject in either treatment arm met criteria for successful outcome. There was no significant change in outcome measures in either group at six months. This study demonstrates no significant benefit from IDET over placebo.

Introduction and Aims: Trans-laminar screw fixation is a popular method of posterior stabilisation when performing a 360-degree lumbar fusion, but many have concerns over the biomechanical stability of this construct. The objective of this paper is to compare the fusion rate and clinical outcome of this method with pedicle screw fixation.

Method: During 2001, 31 patients underwent combined anterior and posterior fusion by the two senior surgeons for the treatment of discogenic low back pain. Anterior interbody fusion was performed using the Syncage LR in all patients. Sixteen patients underwent trans-laminar screw fixation posteriorly and 15 underwent pedicle screw fixation. Fusion was assessed by fine cut CT scan at one year post-operatively. Function was assessed with pre- and post-operative Low Back Outcome Score and visual analogue pain scores.

Results: The average follow-up was 15.5 months. The incidence of pseudarthrosis in the trans-laminar screw group was approximately 80% (15 out of 19 levels), compared to 20% (4 of 21 levels) in the pedicle screw group (p < 0.05). There were trends towards greater improvements in the LBOS and VAS scores in the pedicle screw group. There were two surgical complications in the trans-laminar screw group and one in the pedicle screw group

Conclusion: The use of trans-laminar screws is associated with a significantly higher rate of pseudarthrosis compared to pedicle screw fixation. Assessing fusion with fine cut CT scans has revealed a higher rate of pseudarthrosis with trans-laminar screw fixation than has previously been reported

Introduction Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but to date there are no published randomized controlled trials assessing efficacy versus a placebo group.

Methods Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed to improve with conservative therapy were considered. Inclusion criteria included the presence of one or two level symptomatic disc degeneration with posterior or postero-lateral annular tears as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or previous back surgery. Fifty-seven patients were randomized with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham procedure (placebo). In all cases the IDET catheter was positioned under sedation to cover at least 70% of the annular tear defined by the CT/discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Both surgeon and patients were blinded to the treatment. Patients followed a standard post-procedural rehabilitation programme. Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and six months. Successful outcome was defined as: no neurological deficit resulting from the procedure, improvement in LBOS of > 7 points, improvements in SF-36 subsets (pain/disability, physical functioning and bodily pain). Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and workers’ compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups.

Results No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at six months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the placebo group. There was no significant change in ZDI or MSPQ scores for either group. No subject in either treatment arm met criteria for successful outcome. Further analysis showed no significant change in outcome measures in either group at six months.

Conclusions This study demonstrates no significant benefit from IDET over placebo.

Introduction: 360 degree combined anterior and posterior fusion is an accepted surgical treatment for the management of discogenic back pain. Controversy exists to the optimal technique of posterior fixation. Proponents of translaminar screw fixation cite lower morbidity as a result of less dissection. Despite reports of high fusion rates with this technique, there are concerns over the biomechanical inferiority of this construct compared to pedicle screw fixation. Previous studies on translaminar screws have used only plain radiographs to assess fusion. The objective of this paper is to compare radiographic outcomes, using high definition CT scans, and clinical outcomes between these two methods of posterior fixation.

Methods: During 2001, 31 patients underwent combined anterior and posterior fusion by the two senior surgeons for the management of back pain. Anterior interbody fusion was performed using the Syncage in all patients. 16 patients underwent translaminar screw posterior fixation and 15 underwent pedicle screw posterior fixation. Fusion was assessed by high definition CT scan at one year postoperatively. Function was assessed with pre- and postoperative Low Back Outcome Score and visual analogue scores.

Results: Minimum follow-up was 12 months. The incidence of pseudarthrosis in the translaminar group was over 75% which was five times greater than that seen in the pedicle screw group (p = 0.01). There were trends towards greater improvements in the LBOS and VAS scores in the pedicle screw group and amongst those patients who achieved a successful fusion. There were two surgical complications in the translaminar screw group and one in the pedicle screw group.

Discussion: With the numbers that are available, there are no clinical differences between the two methods of fixation, although there were trends towards improved function and reduced pain in the pedicle screw group. Furthermore there does not appear to be any difference in regards to complications. However, translaminar screws are associated with a significantly higher rate of pseudarthrosis compared to pedicle screws.

INTRODUCTION: Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but to date there are no published randomised controlled trials assessing efficacy versus a placebo group.

METHODS: Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed to improve with conservative therapy were considered for the study. Inclusion criteria included the presence of one or two level symptomatic disc degeneration with posterior or posterolateral annular tears as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or previous back surgery. Fifty-seven patients were randomised with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham procedure (placebo). In all cases the IDET catheter was positioned under sedation to cover at least 70% of the annular tear defined by the CT/ discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Both surgeon and patient were blinded to the treatment. Patients followed a standard post-procedural rehabilitation programme.

OUTCOME MEASURES: Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and six months. Successful outcome was defined as: No neurological deficit resulting from the procedure, improvement in LBOS of > 7 points, improvements in SF-36 subsets (pain/disability, physical functioning and bodily pain)

RESULTS: Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and worker’s compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups.

No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at six months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the Placebo group. There was no significant change in ZDI or MSPQ scores for either group.

DISCUSSION: No subject in either treatment arm met criteria for successful outcome. Further analysis showed no significant change in outcome measures in either group at six months. This study demonstrates no significant benefit from IDET over placebo.

INTRODUCTION: 360 degree combined anterior and posterior fusion is an accepted surgical treatment for the management of discogenic back pain. Controversy exists to the optimal technique of posterior fixation. Proponents of translaminar screw fixation cite lower morbidity as a result of less dissection. Despite reports of high fusion rates with this technique, there are concerns over the biomechanical inferiority of this construct compared to pedicle screw fixation. Previous studies on translaminar screws have used only plain radiographs to assess fusion. The objective of this paper is to compare radiographic outcomes, using high definition CT scans, and clinical outcomes between these two methods of posterior fixation.

METHODS: During 2001, 31 patients underwent combined anterior and posterior fusion by the two senior surgeons for the management of back pain. Anterior interbody fusion was performed using the Syncage in all patients. 16 patients underwent translaminar screw posterior fixation and 15 underwent pedicle screw posterior fixation. Fusion was assessed by high definition CT scan at one year post-operatively. Function was assessed with pre- and post-operative Low Back Outcome Score and visual analogue scores.

RESULTS: Minimum follow-up was 12 months. The incidence of pseudarthrosis in the translaminar group was over 75% which was five times greater than that seen in the pedicle screw group (p = 0.01). There were trends towards greater improvements in the LBOS and VAS scores in the pedicle screw group and amongst those patients who achieved a successful fusion. There were two surgical complications in the translaminar screw group and one in the pedicle screw group.

DISCUSSION: With the numbers that are available, there are no clinical differences between the two methods of fixation, although there were trends towards improved function and reduced pain in the pedicle screw group. Furthermore there does not appear to be any difference in regard to complications. However, translaminar screws are associated with a significantly higher rate of pseudarthrosis compared to pedicle screws.

Seven psoas bursae filled with purulent fluid and inspissated debris were revealed at revision operations for failed resurfacing hip arthroplasties, an incidence of 5.8% in such revisions. Histological and microbiological investigations demonstrated that the psoas bursa collections resulted from the tissue response to polyethylene wear debris. None was due to infection.