Introduction: Avascular Necrosis (AVN) of the femoral head is a complex disease that often leads to disabling hip pain and degenerative arthritis. Core decompression is currently the most common procedure used to treat the early stages of AVN but used alone may not provide adequate structural support. Trabecular metal may be a promising development by providing the support needed after a core decompression while minimizing the surgical complications of bone grafts. The important stiffness is similar to a fibular graft and the implant enables vascular healing via its porosity. This is a small series of patients who underwent this procedure which is minimally invasive. All patients had a non-traumatic aetiology for the AVN and were referred from a Rheumatology clinic closely linked to the orthopaedic clinic.

Methodology: This is a retrospective review of consecutive patients who underwent core decompression and insertion of trabecular metal (tantalum) screw for AVN of the femoral head. Preoperatively the severity of the AVN was assessed with the help of a radiologist using a modified Ficat classification (Steinberg 1986) with magnetic resonance imaging. Postoperatively the progression was assessed with x-rays.

Results: A total of nine trabecular screws were inserted into five patients with four receiving bilateral operations. Medium age was forty-five years (range 32–57) and 60% males (n=3). Steroids were thought to be the predisposing factor for AVN in all cases. Preoperative MRI studies showed Grade II disease in four hips (44.4%) Grade III in four hips (44.4%) and Grade IV disease in one hip (11.2%) Median follow up time was 14.4 months range (3–27 months). The hip with Grade IV disease went onto develop destruction of the joint and required a total hip replacement fifteen months later. This was a straightforward procedure with easy removal of the implant. The remaining hips have not required revision to date. There have been no implant failures, migration or loosening. This procedure may prove to be a clinically viable implant option for AVN and the study is ongoing. A major problem is the difficulty in seeing patients early enough with early stage disease. (stage 0, stage I and II.) There have been no implant failures migration or loosening to date.

Introduction: Autologous bone graft is currently considered the gold standard for anterior cervical discectomy and fusion (ACDF). However, the harvesting of bone graft from the ilac crest is frequently associated with significant patient morbidity. We report on the safety and efficacy of trabecular metal blocks for achieving a stable interbody fusion for ACDF when compared to iliac crest bone graft for a small group of patients.

Methods: This is a prospective trial of patients who underwent consecutive ACDFs between September 2004 and September 2007. Patients received one of two materials for their fusion, either trabecular metal blocks or autologous iliac crest bone graft. Each operation was performed by the same spinal surgeon (LT), and all patients had fixation with an anterior titanium plate to enhance interbody arthrodesis. Clinical outcome was assessed with a neck disability score (Vernon and Mior 1991) that was mailed to all participants; bone graft patients were also asked to complete a bone graft morbidity questionnaire (Silber et al. 2003). Radiological followup was assessed with computed tomography and flexion-extension radiographs. A minimum followup time of 3 months was required for inclusion into the study, and unpaired t-tests were used to evaluate statistical differences between relevant sets of data.

Results: A total of 31 patients were included into the study, with 15 in the trabecular metal group (TM) and 16 in the iliac crest bone graft group (ICBG). The TM group included 10 males (67%) with a median age of 42 years (range 18–72). Median neck disability score was 18% (2–38) and stable bony ingrowth was observed in all patients (100%) on postoperative scans. Median followup time was 8 months (3–16) for TM patients and 20.3 months (7–36 months) for the ICBG group. In comparison, the ICBG group included 8 males (50%) with a median age of 53.3 years (43–70). Median neck disability score was worse at 30% (4–50), with a significant difference of 12% observed after t-test analysis (p value < 0.02). In addition, there was significant morbidity associated with the harvesting of autologous bone graft, with more than 50% of patients experiencing acute and/or chronic symptoms. Two radiological pseudoarthroses (8%) were observed postoperatively, of which one was manifested clinically.

Discussion: These results confirm that, for our population group, trabecular metal implants are both safe and effective for use in ACDF when compared to the gold standard of autologous bone graft. Furthermore, trabecular metal implants avoid the morbidity associated with the harvesting of iliac crest bone graft. We believe the results so far are encouraging for our small group of patients but a larger, randomised control trial is needed to provide definitive results.

The aim was to evaluate the Intraobserver and Interobserver reliability of Pelvic Incidence as a fundamental parameter of sagittal spino-pelvic balance in patients with spondylolisthesis compared to controls with Idiopathic Adolescent Scoliosis.

A blinded test retest study including multi-surgeon assessment of Pelvic Incidence in patients with spondylolisthesis and Idiopathic Adolescent Scoliosis was carried out. We assessed the agreement between the pelvic incidence measurements using the Bland and Altman method and mean differences (95% confidence interval) are reported.

Forty patients seen at Starship Children’s Hospital between 1992 – 2003 by two spinal surgeons were retrospectively identified. The main group had 20 patients with spondylolisthesis (Isthmic and/or Dysplastic types) and the control group consisted of 20 patients with Idiopathic Adolescent Scoliosis. Five observers with different levels of experience included the two orthopaedic surgeons, one fellow, one senior trainee and one non-trainee registrar. Prior to the initial test phase, a consensus-building session was carried out. All five observers arrived at a standardised method for measuring the Pelvic Incidence. In the test phase randomly ordered lateral lumbosacral radiographs were independently evaluated by the five observers and pelvic incidence was measured. Assessment of the Pelvic Incidence was repeated one week later in the re-test phase. The radiographs were presented in a randomly pre-assigned order. Bland and Altman plots were constructed and mean differences (95% confidence interval) reported to evaluate the agreement between the Pelvic Incidence measurements among the five independent observers. All analysis was performed on the statistical software package SAS. P-value of 0.05 was considered statistically significant.

The spondylolisthesis group had 11 (55%) males and 9 (45%) females with an average age of 14 ± 4.2. 2 patients had high-grade (Meyerding Class III, IV, V) and 16 had low-grade (Meyerding Class I, II) spondylolisthesis. 2 patients were post-reduction of spondylolisthesis. In the Scoliosis group there were 2 (10%) males and 18 (90%) females with an average age of 15 ± 2.9. There was no significant difference between male and females pelvic incidence measurement (60° ± 18.7° vs. 57° ± 14.6°, p=0.540) or age (15 ± 2.9 vs. 14 ± 3.8, p=0.181). There was no difference in pelvic incidence across the Meyerding groups, p=0.257. There was a significant difference between spondylolisthesis and scoliosis pelvic incidence measurements 65° ± 15.6° vs. 51° ± 12.8°, p=0.003. In the Spondylolisthesis Group the interobserver reliability between five clinicians, expressed as the mean difference in pelvic incidence measurement was 0.6° (95%CI −0.81, 1.91) and was not significantly different from zero p=0.423. The agreement limits were from −12.8° to 13.9°. The intraobserver reliability of pelvic incidence showed the mean difference ranging from −2.1° to 1.4° (p=0.129 and 0.333 with 95% CI). One had marginal evidence of a significant difference of 3.3° (95% CI 0.05° to 6.55°, p=0.047). In the Scoliosis Group the interobserver reliability was 0.3° (95% CI −0.81, 1.49) and was not significantly different from zero p=0.726. The agreement limits were from −11.0° to 11.6°. The intraobserver reliability among four observers ranged from −1.7° to 0.5° (p=0.178 and 0.661). One had a significant difference in readings of 4.1° (95% CI of 0.70° to 7.40°, p= 0.020).

Scoliosis patients had a significantly smaller pelvic incidence than spondylolisthesis patients. The interobserver reliability of the pelvic incidence measurement was excellent across both groups. The intraobserver reliability was good with only one observer in each group demonstrating a marginally significant difference. Pelvic incidence is therefore a reliable measurement which can be used as a predictor in progression of spondylolisthesis.

The aim was to compare the efficacy and outcomes of reduction of closed forearm fractures in a paediatric population using Ketamine in the Emergency Department (ED) setting versus reduction under general anaesthesia (GA) in the operating theatre (OT).

A prospective audit of children presenting to our institution with closed fractures of the radius and/or ulna was conducted. Patients presenting to ED were offered manipulation under GA or Ketamine, and then grouped accordingly. Children were followed up until full range of motion had recovered. Outcomes measured at follow up were 1) need for remanipulation, 2) position at union, 3) total hospital stay and 4) functional outcome.

Forearm fractures account for 22% of acute paediatric orthopaedic admissions to our institution. 70% require manipulation and splintage. 221 forearm fractures required manipulation during the study period. 90 patients (41%) were manipulated under Ketamine in the ED, 131 patients (59%) were manipulated in the OT. There was no significant difference in mean angulation of fractures treated by either method (p=0.20). There was no significant difference between the two methods with respect to rates of remanipulation (p=0.73) or poor position at union (p=0.55). There was a significantly shorter hospital stay for those treated in the ED.

Treatment of paediatric forearm fractures in the ED under Ketamine sedation offers an effective alternative for selected fractures. It also offers considerable financial savings and is less of a drain on valuable theatre and staff resources.

Introduction and Aims: Children and adolescents with back pain are a challenging problem for the orthopaedic surgeon. The differential diagnosis includes tumors and infection. The aim of this retrospective review was to determine the incidence amongst the study population and ascertain the clinical markers that could help clinicians to diagnose the underlying pathology.

Method: A clinical records database search identified a cohort of 59 consecutive patients referred to one of two paediatric spinal surgeons with the diagnosis of back pain between January 2000 and July 2003. The record analysis included chart review, radiographic analysis and clinical follow-up at the Starship Children’s Hospital. Patients were excluded from the study if they were referred with a known cause of back pain, had previous spinal surgery or a cervical distribution of pain.

Results: New back pain referrals represented 1.7% of all new referrals to this tertiary level orthopaedic department. There were 59 patients with 32 (54%) females and 27 (46%) males. The average age at presentation was 12 years and the average duration of symptoms was 15.5 months. The most common site of pain was lumbosacral (61%). All patients had plain radiograph studies performed, 28 (47.5%) a bone scan, nine (15%) a CT scan and 15 (25.5%) an MRI. In addition, 21 patients (35.5%) had laboratory investigations including a FBC, ESR and c-reactive protein.

Thirty-four patients representing 58% of the study group had a definitive dignosis made. Fourteen patients (24%) had Scheuerman’s disease, seven (12%) were dignosed with spondylolisthesis and five (8.5%) had a painful scoliosis. Only one patient had osteomyelitis. We did not identify any patients with a tumor.

Patients older than 10 years were almost twice as likely to have a positive diagnosis than those under 10 years of age. There was no single reliable clinical sign or symptom that would help make the diagnosis. Significant haematological abnormalities were only found in one patient who was diagnosed with sacral osteomyelitis. Plain radiographs alone provided the diagnosis in 14 (23.5%) patients. Bone scan, CT and MRI were of variable diagnostic value.

Conclusion: Back pain in children has traditionally been regarded serious enough to warrant comprehensive investigation. We have found a definitive diagnosis in only 58% of patients despite thorough clinical assessment, and haematological and radiological evaluation. Clinicians must remain vigilant for any clues that may help lead to a diagnosis in this group of patients.

Introduction This is an outcome study of the patients with spina bifida treated for scoliosis by anterior and posterior spinal surgery by a single surgeon at one institution.

Method The clinical notes and radiographs were reviewed of all spina bifida patients with scoliosis undergoing surgery between January 1991 and January 2001. In addition all patients were sent the Spina Bifida Health Related Quality of Life Questionnaire (HRQOL) and the Spina Bifida Spine Questionnaire (SBSQ).

Results There were 19 consecutive patients with an average age at surgery of 13 years 5 months (range). The average neurologic level was T10 (range). 14 patients had staged procedures. At latest follow-up which averaged 60 months (range), there was an overall improvement in scoliosis of 61% from a mean of 83 degrees preoperatively to a mean of 34 degrees postoperatively. There was a corresponding 70% improvement in pelvic obliquity from 27 degrees preoperatively to 8 degrees postoperatively. At latest follow-up which averaged 60 months (range). The major complications included 4 deep infections and 2 pseudarthroses. The deep infections occurred in older patients with more severe curves and were always staged procedures. The patients scored an average of 68.8 on the SBSQ (what does this mean?). The average score on the HRQOL questionnaire for patients 5–12 year old was 178 and 163 for 13–20 year olds.

Discussion There are good radiological results with combined anterior/posterior surgery in this group of spina bifida patients. The outcome scores show that this group of patients enjoy a good quality of life when compared to control groups of similar children with the same condition. An early single stage anterior and posterior spinal fusion is recommended for these patients before the scoliotic curve becomes too large and stiff.

The purpose was to compare the results of two different surgical techniques in the treatment of severe cerebral palsy scoliosis.

This is a retrospective review of 12 consecutive cerebral palsy patients with scoliosis greater than 90 degrees undergoing simultaneous anterior and posterior spinal fusion. The clinical notes were reviewed along with sequential radiographs. Twelve patients were operated on between March 1997 and October 2001. There were 6 patients who had anterior release and fusion followed by posterior fusion from T2 to the sacrum using the Luque-Galveston technique. (Group 1). The other 6 patients had identical surgery but with the addition of anterior instrumentation as well. (Group 2). There was no loss of fixation or metalware failure. There was no pseudarthrosis. One patient died at the time of rod removal for infection 2 years following their index operation.

These results show that a good outcome is achieved in this group of severely affected cerebral palsy patients using either of the techniques described. The addition of anterior instrumentation may make the surgery easier and was not associated with significant increase in complications.

This is an outcome study of patients with spina bifida treated for scoliosis by anterior and posterior spinal surgery at the Starship Children’s Hospital.

The clinical notes and radiographs were reviewed of all spina bifida patients with scoliosis undergoing surgery between January 1991 and January 2001. In addition all patients were sent the Spina Bifida Health Related Quality of Life Questionnaire (HRQOL) and the Spina Bifida Spine Questionnaire (SBSQ). There were 19 consecutive patients with an average age at surgery of 13 years 5 months. Four patients had both anterior and posterior instrumentation. 14 patients had staged procedures.

There was an overall improvement in scoliosis of 61% and pelvic obliquity of 70% at latest follow-up that averaged 60 months. The major complications included 4 deep infections and 2 pseudarthroses. The patients scored an average of 68.8 on the SBSQ. The average score for 5–12 years old was178 and for 13–30 years old, 163, on the HRQOL questionnaire. There are good radiological results with combined anterior/posterior surgery in this group of spina bifida patients. Quality of Life does not seem to be greatly compromised in the operated spina bifida patient.

We recommend early single stage anterior and posterior fusion for these patients before the curve becomes too large and stiff.

Aim: To determine the length of stay after adolescent idiopathic scoliosis (AIS) surgery in Starship and Mercy Hospitals to ascertain whether there is a difference in the length of stay of patients having AIS surgery in a private hospital compared with a public hospital. To determine the variables having significant influence on the length of stay.

Methods: Patients between the ages of 10 and 20 who had surgery for AIS during the period 1/1/96 to 31/12/2000 were identified from theatre logbooks. Patients who had anterior and posterior surgery were excluded. A retrospective analysis of case notes was carried out. Fisher’s Exact Test was used to analyse categorical data while Student T Test was used for continuous variables.

Results: Thirty-three patients fulfilled the entry criteria. Sixteen male patients were operated on in Starship Hospital. Seventeen patients had operations at Mercy Hospital but only one of these was male. The groups were not significantly different in terms of age, sex, weight, ASA, number of levels, or curve pattern. The Mercy Hospital patients had a significantly lower Cobb angle (by 12 degrees). The Starship Hospital patients tended to retain their PCA pumps longer and tended to use more PCA morphine, however, this result was not significant. The Mercy Hospital patients had their intravenous access removed and were mobilised significantly earlier (1.7 and 1.9 days earlier respectively). The Mercy Hospital patients had a significantly shorter length of stay (6.4 and 8.4 days respectively, p= 0.0002).

Conclusions: Patients at the Mercy Hospital had a significantly shorter post-operative length of stay after AIS surgery. This was not completely explained by the lower Cobb angle seen in the Mercy Hospital patients. The Mercy Hospital patients had their drips removed and were mobilised significantly earlier. This may be the key to early discharge.

Introduction: There is a paucity of published data concerning major thoracolumbar spine trauma in the paediatric population, reflecting the rarity of these injuries.

Aim: To review retrospectively 11 cases of thoracolumbar paediatric spinal fractures and dislocations requiring operative management by one surgeon from 1991 to 2001 at Starship Children’s Hospital.

Methods and results: The mean age was 10 years (range: four to 15). Four patients had a neurological deficit (three were incomplete, one was complete). All patients underwent surgery with internal fixation. Canal decompression was achieved by operative realignment in most patients although two patients underwent additional decompression by corpectomy. Seven patients had flexion-distraction injuries with facet joint dislocations. These patients were treated with posterior instrumentations in compression. A further two patients with fracture-dislocations were also treated by posterior instrumentation and the remaining two patients (one burst fracture and one fracture-dislocation) by anterior instrumentation. The general principles for surgical management of thoracolumbar spine trauma in adults were found to be applicable to the children in this series. Suitably sized internal fixation devices were available to allow stabilisation in all cases. The preponderance of dislocations presumably reflects differing biomechanics in the immature versus the adult spine and necessitated a posterior operative approach in most cases.

Previous studies have documented a variation in the occurrence of musculo-skeletal conditions affecting the hip and foot in the New Zealand Maori and Pacific Island races compared with the European race in New Zealand. Similar data regarding scoliosis are lacking. A manual and computerised review of outpatient records of Starship Hospital (1989–2000) and Middlemore Hospital (1997–2000) revealed 363 patients less than 20 years of age with a diagnosis of scoliosis. Major aetiological diagnoses included adolescent idiopathic (63), syringomyelia (12), myelomeningocele (16), cerebral palsy (55) and congenital (55). Significant racial variations were noted in the idiopathic, syringomyelia and neuro-muscular groups compared with New Zealand census predictions. Idiopathic scoliosis was uncommon in Maori (9%) and rare in Pacific Islanders (1%). Conversely, these groups accounted for 66% of all scolioses and over 50% of Maori and Pacific Islanders were found to have a syrinx. MRI is indicated in Maori and Pacific Islanders with apparent adolescent idiopathic scoliosis. Maori accounted for 31% of patients with myelomeningocele and scoliosis. 40% of patients with cerebral palsy and scoliosis were Maori, reflecting the known inferior status of perinatal and other health parameters in this group of people.

We measured pressures in the anterior and deep posterior compartments continuously for up to 72 hours in 20 patients with closed fractures of the tibial shaft treated primarily in plaster casts. All were examined independently after periods of three to 14 months. Pressures above 40 mmHg occurred in seven (35%) and above 30 mmHg in 14 (70%). No patient had the symptoms of compartment syndrome during monitoring. Abnormalities at review did not correlate with the maximum consecutive time periods during which the compartment pressures were raised. Thus, in the absence of symptoms the monitored pressures did not relate to outcome. Routine monitoring in this type of patient is therefore of doubtful benefit.

We studied 50 patients with fractures of the femoral neck, 33 intracapsular and 17 extracapsular. Intraosseous pressure was measured by a transducer within the bone to quantify blood flow, and intracapsular pressure by a needle introduced into the joint space. The mean intracapsular pressure was lower in the extracapsular fractures. In these, the mean intraosseous pressure in the femoral head was unchanged by aspiration of the joint. However in the intracapsular fractures aspiration produced a significant decrease in intra-osseous pressure and an increase in pulse pressure within the femoral head. The results suggest that aspiration of intracapsular haematoma produced an increase in femoral head blood flow by relieving tamponade.

We assessed 16 patients before and after high tibial osteotomy by electrophysiological recordings, creatine phosphokinase levels, radiographs and intracompartmental pressure monitoring. We found mild electrophysiological abnormalities pre-operatively in 12 of the 16 patients, but postoperatively these had deteriorated in 11 of the 14 patients studied. Creatine phosphokinase levels, compartment pressure and radiological deformity were not predictive of the development of postoperative common peroneal nerve palsy. Patients who also had a proximal fibular osteotomy had greater electrical abnormalities postoperatively and two of them developed common peroneal palsies. Proximal fibular osteotomy appears to be a causative factor in the development of common peroneal nerve palsy; more work is needed on the blood supply of the nerve.

The aetiology of pain in the lower leg during exercise has been studied in 110 athletes by monitoring intracompartmental pressure during exercise and by technetium bone scans. Patients were assigned to three diagnostic groups: chronic compartment syndrome, medial tibial syndrome and those with non-specific findings. Our results indicate that subcutaneous fasciotomy of the affected compartment(s) is the treatment of choice for chronic compartment syndrome. The treatment of patients with medial tibial syndrome, either by operation or conservatively, has been unsuccessful; non-specific symptoms have been treated conservatively with success.

Weakness of dorsiflexion of the foot is a common complication of proximal tibial osteotomy and it has been suggested that this may be caused by an anterior tibial compartment syndrome. A prospective study of 20 patients undergoing tibial osteotomy was undertaken, in which compartment pressures were recorded and related to clinical signs. In 10 of the patients, the operation site was drained, and in 10 no drainage was employed. The undrained group showed significant elevation (greater than 45 mmHg) of the anterior compartment pressure in seven patients, and five of these had transient clinical signs. Only one patient had any permanent deficit, a minor asymptomatic weakness of extensor hallucis longus. In the drained group the pressures remained below 30 mmHg in all except two patients, who both had only a minor pressure rise and no significant early clinical signs. However, two patients from this group later developed weakness of dorsiflexion, probably due to common peroneal nerve injury, the cause of which is not clear.

Thirteen patients with ruptures of the calcaneal tendon diagnosed more than four weeks after injury were reviewed. Eleven patients had operative reconstruction with tendon shortening and the postoperative follow-up ranged from one to seven years. Isometric and isokinetic measurements, as well as the strength of the triceps surae, all compared favourably with the normal contralateral leg. Only one tendon re-ruptured. Eight of the eleven patients were satisfied with the results and the two patients who had refused reconstruction had worse functional results. Late reconstruction of a ruptured calcaneal tendon is thus a worthwhile procedure.

Acute compartment syndromes often develop insidiously and are often recognised too late to prevent permanent disability. Management is difficult as the compartment involved is seldom clinically apparent. By continuously monitoring the intracompartmental pressure these problems can be avoided: transient compartment syndromes can be differentiated from established ones and the correct compartment can be surgically decompressed. Pressure monitoring techniques were used in 28 patients; three developed a compartment syndrome requiring surgical intervention, seven had a temporary increase of pressure and in 18 the pressure remained unaltered. Of the three with compartment syndromes, one was unusual in that it affected the thigh and another, unique in our experience, affected both the thigh and the calf. Intracompartmental pressure monitoring significantly altered the management of two cases giving successful results with minimal intervention.