Introduction

This study aimed to assess the relationship between preparation times and operative procedures for elective orthopaedic surgery. A clearer understanding of these relationships may facilitate list organisation and thereby contribute to improved operating theatre efficiency.

Proximal tibial bone mineral density (BMD) has been shown to decrease following Total Knee Arthroplasty (TKA) by both dual-energy x-ray absorbtiometry (DEXA) and quantitative computed tomography (qCT)-assisted osteodensitometry. Little is known about changes in BMD following unicompartmental knee arthroplasty (UKA). Additionally, there are proposed differences in stress transmission between cemented metal and polyethylene (PE) components. We proposed two hypotheses. First, that proximal tibial BMD decreases following UKA. Second, that BMD loss would be greater below metal tibial components.

We performed a prospective clinical trial of 50 consecutive UKAs in 49 patients performed by two surgeons at one institution. There were 25 mobile bearing Oxford and 25 fixed bearing Accuris arthroplasties, all were medial. BMD was assessed with qCT-assisted osteodensitometry scans prior to discharge and then at 1 and 2 years post surgery. Each CT slice was divided into medial and lateral halves and cortical and cancellous bone was analysed separately. The six 2mm slices immediately beneath the tibial implant were analysed using previously validated software to create a three-dimensional assessment of BMD. The lateral half was used as a control.

There were a total of 30 females (60%), with an average age of 70 (49–84). One patient was lost to follow-up and another was unable to be analysed due to failure requiring revision before follow-up was complete. Preliminary results showed no significant change in BMD at either 1 or 2 years follow-up. There was no difference in BMD change between the mobile and fixed bearing prostheses, between the medial and lateral halves nor between cortical and cancellous bone. Final results will be presented at the AONZOA conference.

This trial shows that UKA does not result in significant change to BMD at 2 years. The preservation of BMD may indicate that UKA is better at maintaining physiologic stress transfer than a TKA, which has been shown to be associated with a reduction in BMD.

Since September 1964, neonates born in New Plymouth have undergone clinical examination for Neonatal Instability of the Hip (NIH) in a structured clinical screening programme. Forty one thousand, five hundred and sixty three babies were born during the period of this study, of which 1,638 were diagnosed as having unstable hips. Six hundred and thirty three with persisting instability were splinted (1.6%), with five hips failing splintage. In addition, three unsplinted hips progressed to CDH, and there were four late-presenting (walking) cases of CDH, giving an overall failure rate for the programme of 0.29 per 1000 live births, with a late-presenting (walking) CDH incidence of 0.1 per 1000 live births. This study confirms that clinical screening for NIH by experienced orthopaedic examiners significantly lowers the incidence of late-presenting (walking) CDH.

The volume of spinal procedures have increased over the last two decades (220% in lumbar region). A simultaneous increase in re-operation rates (up to 20%) has been reported. Our aim was to compare with literature the reoperation rates and complications for various spinal procedures from a peripheral unit and to provide this information to the patients

This was a retrospective study of all patients who underwent spinal surgery during the period 1995 to 2005 by one surgeon. Using ICDM-9 codes and private notes patients were identified and medical records were used to gather relevant data. The following information was extracted-demographics, diagnosis, ASA criteria, primary procedure, any complication/s, secondary procedures, duration of follow up and to secondary procedure. The index procedures were grouped into regional and according to indication. Both complications and reoperations were grouped into early (within three months) or delayed (after three months) from the index operation. Reoperation rates and complications were calculated and compared with literature.

Four hundred and thirty-nine patients formed the study population. Five patients had inadequate data and were excluded. 23 patients have since died. Demographics showed 22% were smokers and 9% were either unemployed or sickness beneficiary. The commonest diagnosis in the lumbar spine was disc herniation (194). Stenosis and disc degeneration were the next most common surgical indications. In the cervical spine 27 patients had disc herniation and 15 patients were operated for trauma. Lumbar discectomy was the commonest procedure-191 patients with one third having microdiscectomy. Instrumented fusion was performed in 97 while 37 patients underwent decompression only. The majority of cervical spine patients (46) had discectomy and fusion.

Stabilisation for trauma formed a reasonable workload in both cervical and lumbar regions. Early complications included dural tears (seven), neurological symptoms (eight), wound infections (12) and pulmonary embolism (one) and repeat disc herniation. Delayed problems included repeat disc herniation, pseudoarthrosis and implant related symptoms. Overall re-operation rate was 14.52% with 5.02% early and 9.4%delayed repeat surgery. Repeat discectomy (eight) and decompression and exploration (seven) were the common early reoperation whereas fusion post discectomy (19) and recurrent disc herniation (12) were indications for delayed intervention. Removal of metalware (8) was another large late re-operation group.

Our re-operation rates fall within the quoted figures in literature. However our early re-operation rates are somewhat higher. These figures help us to inform patients better at the time of consent for the primary procedure especially lumbar disc surgery as most of the re-operation were required after discectomy.

Since September 1964, neonates born in New Plymouth have undergone clinical examination for instability of the hip in a structured clinical screening programme. Of the 41 563 babies born during this period, 1639 were diagnosed as having unstable hips and 663 (1.6%) with persisting instability were splinted, five of which failed. Also, three unsplinted hips progressed to congenital dislocation, and there were four late-presenting (walking) cases, giving an overall failure rate of 0.29 per 1000 live births, with an incidence of late-walking congenital dislocation of the hip of 0.1 per 1000 live births.

This study confirms that clinical screening for neonatal instability of the hip by experienced orthopaedic examiners significantly reduces the incidence of late-presenting (walking) congenital dislocation of the hip.

Cortisone injection for radicular leg pain may be useful in treating patients with lumbar foraminal pathology based on accurate CT/MRI diagnosis and operator-controlled biplanar fluoroscopy in an angiography suite.

Patient details were collected from operative records and angiography suite records. Demographic data, diagnosis and level of injection were recorded. Low Back Outcome Scores (LBOS) were collected prospectively for most patients. Patients were then posted a questionnaire, including the LBOS. Patients were excluded from further analysis if further injection or surgery was required.

Fifty eight patients, all with CT or MRI diagnosis, underwent lumbar foraminal steroid injection. Thirty-seven had disc protrusion (64%) and twenty-one had stenosis (36%). Eighteen (31%) patients required further intervention, eleven with stenosis (52%) and seven with disc protrusion (19%). Thirty-two patients (80%) completed follow up questionnaires, one patient had died, one was lost to follow up, and six patients declined to complete the questionnaires. The average LBOS for the thirty-two patients who completed the questionnaires was 41.8+/−17.5. Twenty-three patients with pre-treatment LBOS improved on average from 25.1+/−13.5 to 45.9+/−16.1 following injection (p=0.050). Of this group, the eight patients with stenosis improved from 28.8+/−12.3 to 41.6+/−15.9 (average 12.9). The fifteen patients with disc protrusion improved from 23.2+/−14.1 to 48.1+16.3 (average 24.9). This difference in improvement between the two groups was significant (p=0.016).

This study reports 81% of patients with disc protrusions not requiring further treatment, with improvement of the average LBOS to 48.1=/−16.3. However the results in patients with foraminal stenosis was less satisfactory.

Introduction Cortisone injection for radicular leg pain may be useful in treating patients with lumbar foraminal pathology based on accurate CT/MRI diagnosis and operator-controlled biplanar fluoroscopy in an angiography suite.

Methods Patient details were collected from operative records and angiography suite records. Demographic data, diagnosis and level of injection were recorded. Low Back Outcome Scores were collected prospectively for most patients. Patients were telephoned and then posted a questionnaire including the LBOS. Taranaki Ethics Committee approval was obtained. Patients were excluded from further analysis, following a single fluoroscopically-controlled foraminal injection of 80 mg triamcinolone for radiculopathy, if further injection or surgery was required.

Results Between 1995 and 2004, 58 patients, all with CT or MRI diagnosis, underwent lumbar foraminal steroid injection. Thirty-seven had disc protrusion (64%) and twenty-one had stenosis (36%). Eighteen (31%) required further intervention (six: repeat injection, 3: discectomy, 8: decompression), in eleven patients with stenosis (52%) and seven patients with disc protrusion (19%). Forty patients had no further intervention. Thirty-two patients (80%) completed follow-up questionnaires, one patient had died, one was lost to follow-up, and six patients declined to complete the questionnaires despite being contacted. The average LBOS for the thirty-two patients who completed the questionnaires was 41.8 (±17.5). Twenty-three patients with pre-treatment LBOS improved on average from 25.1 (±13.5) to 45.9 (±16.1) following injection (p=0.050). The eight patients with stenosis improved on average 24.9 points from 28.8 (±12.3) to 41.6 (±15.9). This is not statistically significant (p=0.95). The fifteen patients with disc protrusion improved significantly from 23.2 (±14.1) to 48.1 (±16.3) at follow-up (p< 0.01). This difference in improvement between the two groups was significant (p=0.016).

Discussion Weiner and Fraser (Weiner BK, et al; J Bone Joint Surg Br. 1997) recommended foraminal steroid injection as the primary treatment for foraminal or extraforaminal disc protrusions, describing 79% patients having long term pain relief with an average follow-up LBOS score of 54 out of a possible 75 points. This present study reports 81% of patients with disc protrusions not requiring further treatment, with an overall average improvement in the follow-up LBOS score to 48. However the results in patients with foraminal stenosis were significantly less satisfactory.

Introduction: The purpose of this case report is to highlight an unusual presentation of a well-described but rare condition (idiopathic spinal epidural lipomatosis) in association with a commonly presenting problem (far-lateral disc herniation).

Methods: Retrospective case report and review of the literature.

Results: A 46-year-old Caucasian male presented with right L5 radiculopathy secondary to a far-lateral lumbosacral disc protrusion, confirmed on MRI scanning. Treatment consisted of a right L5 foraminal steroid injection with a 50% improvement in symptoms. This was soon followed by symptoms of spinal stenosis, and repeat MRI showed worsening of idiopathic spinal epidural lipomatosis seen on the initial scan. Over this period the patient had been unable to exercise regularly and had gained 10 kg of weight. Nonoperative treatment, including a supervised Xenical weight-reduction program (which was unsuccessful), failed to alleviate his symptoms so operative decompression was performed, with satisfactory resolution of the stenotic symptoms.

Discussion: Spinal epidural lipomatosis may be idiopathic or secondary to excess steroids (endogenous or exogenous). It affects either the thoracic or lumbar spine. Treatment options are withdrawal of exogenous steroids, weight reduction or decompressive surgery. In this case, disability associated with a far-lateral disc herniation resulted in weight gain, and subsequent stenotic symptoms from previously asymptomatic lumbar idiopathic spinal epidural lipomatosis.

Introduction: Satisfactory ten-year survival statistics from the Swedish Arthroplasty Register, combined with new minimally-invasive surgical implantation techniques, have seen a resurgence in interest in unicompartmental knee arthroplasty (UKA).

Aim: To compare unicompartmental component positioning following minimally invasive and open implantation.

Methods: The radiographs of patients with UKAs implanted using a minimally invasive technique were retrospectively compared with a similar number of UKAs implanted using an open technique. Optimal component positioning and methods of determining this from radiographs will be presented.

Results: Twenty-three consecutive Ripicci UKAs (21 patients) were implanted using a minimally invasive technique. Radiographs were compared with an equivalent number of Marmor UKAs implanted using an open technique. All patients derived from a single surgeon’s practice. Preliminary results indicated that tibial tray positioning was satisfactory, and that variations in the femoral component positioning were due largely to the design modifications of the Ripicci UKA.