We present a large single surgeon case series evaluation of a new growth guidance technique for the treatment of progressive early onset scoliosis (EOS). A traditional Luque trolley construct uses wires to hold growth guidance rods together. We describe a new technique that uses domino end to side connectors in place of the wires with the aim of providing a stronger construct to better limit curve progression, while allowing longitudinal growth.

We did a thorough retrospective review of patient records and radiological imaging. Sequential measurements of Cobb angle and length of rods were recorded, as well as any further surgical procedures and associated complications. This enabled us to quantify the ability of a technique to limit curve progression and simultaneously allow growth of the construct. In total, 28 patients with EOS (20 idiopathic, four syndromic, and four neuromuscular) have been treated with this technique, 25 of whom have a minimum follow-up of 2 years and 13 have a minimum follow-up of 5 years.

The average correction of the preoperative Cobb angle was 48.9%. At the 2-year follow up, the average loss of this initial correction was 15 degrees, rising to only 20 degrees at a minimum of 5 years (including four patients with a follow-up of 8 years or more). The growth of the constructs was limited. The average growth at 2 years was 3.7 mm, rising to 19 mm at the 5-year follow-up.

Patients who underwent surgery with this technique before the age of 8 years seemed to do better. This group had a revision rate of only 18% at an average time of 7 years after the index procedure, and the average growth was 22 mm. However, the group that had index surgery after the age of 8 years had a 64% revision rate at an average of 3.2 years after surgery and an average growth of only 11.6 mm. Overall, in the cases series, there were four hardware failures (14%) and one deep infection (3.5%), and only ten patients (36%) had one extra surgery after the index procedure. Only two of the 13 patients who are at a follow-up of 5 years or more have had revision.

This modified Luque trolley technique has a good capacity for initial curve correction and for limiting further curve progression, with limited longitudinal growth before 2 years and improved growth thereafter. This technique might not be so useful after the age of 8 years because of poor growth and a higher early revision rate. We have also demonstrated a low cost technique with a low hardware failure rate that saves many future surgeries for the patient compared with other techniques used in the treatment of EOS.

Purpose of study: Evaluate our surgical site infection (SSI) rate in scoliosis surgery against nationally agreed standards, examine local practices to limit SSI and compare metalwork survivorship in the presence of infection.

Methods and Results : Retrospective analysis of patients undergoing instrumented correction of scoliosis with or without fusion between September 2003 and January 2009. Clinical and laboratory records of 134 patients (age range 10 months to 22 years) were examined for any evidence of SSI. There were 14 (10.4%) SSI cases, of which 8 (5.9%) were clinically significant deep SSIs, which is slightly higher than a pooled SSI rate of 2.2% from a meta-analysis of infection in spinal surgery (range 1.2 to 8.5%)1. Half of our deep SSIs occurred in neuromuscular scoliosis corrections with the most prevalent pathogen being E. Coli (28%) overall. All deep SSI patients underwent surgical debridement and iv antibiotics and we were able to retain the metalwork in all early (within 21 days) SSIs (6 of 8) but in neither late SSI (588 and 814 days). No single common variable was identified from our data-set as a risk factor for SSI although high staff numbers in theatre was noted. Infection rate increased toward the end of our series which coincided with a change in antibiotic prophylaxis protocol and paradoxically with a move to a laminar flow theatre.

Conclusion : Our SSI rate in scoliosis surgery was not significantly higher than previously published pooled rates. No single common variable was identified as risk factor for SSI. An empirical return to previous antibiotic prophylaxis could be recommended along with limiting staff numbers and movements within the operating theatre.

Ethics approval: Audit/service standard in trust

Conflict of Interest Statement: None

Study Design/Objectives: A pilot study to predict thoracolumbar kyphosis progression secondary to fracture in non-operatively treated patients.

Summary of Background Data: Progressive saggital plane deformity can cause persistent pain after thoracolumbar vertebral fractures. Little data exists to suggest at what interval after the index injury the patient attains a low risk of developing further angular deformity in non-operatively treated patients.

Methods: Supine and erect radiographs were assessed and the degree of fracture kyphosis was determined using an Oxford Cobbometer. The fracture kyphosis was recorded for each follow up appointment along with time after the fracture. A time/data analysis was performed using the Blyth-Still-Casella exact interval.

Results: This study included 22 patients (13 male, 9 female) with average age 67.2 years (range, 14–87 years). The average length of follow up was 11.5 months (range, 5.3–19.9 months) and the average number of radiographs taken within this period was 4 (range, 2–6). The change in fracture kyphosis was plotted against time following fracture. Based on 15 patients with data extending to 200 days follow up, it was observed that the rate of change in fracture kyphosis between two time points of 100 and 150 days predicted the trend in kyphosis progression until the end of follow up in 14 out of the 15 patients. This observed rate of 14/15 (0.93) has a 95% confidence interval of 0.7 to 0.99 (Blyth-Still-Casella exact interval).

Conclusions: The standing lateral radiograph of patients with conservatively treated thoracolumbar fractures at 3 and 4.5 months post injury can be used to predict fracture kyphosis progression. Using this protocol, patients can be safely discharged earlier from outpatient follow up reducing radiological exposure.

Objectives: Ex vivo biomechanical study to compare the properties of isolated, fractured, vertebral bodies after treatment by kyphoplasty with one of two bone tamps: a balloon bone tamp (Kyphon®) or an expandable polymer bone tamp (SKyBone®).

Methods: Simulated compression fractures were created in 21 vertebral bodies (L3–5) harvested from red deer (sp. elaphus. elaphus), with initial strength and stiffness determined concurrently. Deer spine was selected as an alternative to human cadaveric spine due to its availability and its very similar bone density and morphological profile. Vertebral bodies were assigned to one of three groups: (1) unaugmented (control); (2) kyphoplasty using a balloon bone tamp (BBT); and (3) kyphoplasty using a polymer bone tamp (PBT). The kyphoplasty treatment consisted of deploying the bone tamp biped-icularly, then filling the created voids with standardised low viscosity cement. All vertebrae were then recom-pressed to determine their augmented strength and stiffness. Data was analysed using one-way analysis of variance test and paired samples T-Test.

Result: Following fracture and subsequent kyphoplasty augmentation, the median strength of the BBT group was 6.71kN (± 2.71) vs 7.36kN (± 3.43) in the PBT group. Median stiffness in the balloon bone tamp group was 1.885 kN/mm (± 0.340) compared with 1.882 kN/ mm (± 0.868). Augmented strength tended to be greater in the PBT group than for BBT group, but this difference was not significantly different (p> .8). Significantly greater strength was obtained after kyphoplasty using BBT or PBT, compared with control group (p=.001 and .04, respectively). BBT and PBT groups were not statistically different for augmented stiffness (p=.4). Both BBT and PBT groups have greater augmented stiffness as compared to the control group (p=.007 and .005, respectively).

Conclusions: The use of a polymer bone tamp creates similar augmented vertebral body strength and stiffness as compared with the widely used balloon bone tamp in a deer spine model. Similar results would be expected in human spine and consequently the polymer bone tamp may be used as an alternative bone tamp for kyphoplasty.

We performed a biomechanical study to compare the augmentation of isolated fractured vertebral bodies using two different bone tamps. Compression fractures were created in 21 vertebral bodies harvested from red deer after determining their initial strength and stiffness, which was then assessed after standardised bipedicular vertebral augmentation using a balloon or an expandable polymer bone tamp.

The median strength and stiffness of the balloon bone tamp group was 6.71 kN (sd 2.71) and 1.885 kN/mm (sd 0.340), respectively, versus 7.36 kN (sd 3.43) and 1.882 kN/mm (sd 0.868) in the polymer bone tamp group. The strength and stiffness tended to be greater in the polymer bone tamp group than in the balloon bone tamp group, but this difference was not statistically significant (strength p > 0.8, and stiffness p = 0.4).

In 1991 15% of the UK population that travelled abroad required medical assistance. We have been treating more patients with lower limb injuries requiring repatriation via aircraft. Recommendations from Airlines were unavailable. 357 Consultants replied to a questionnaire about transportation of patients with a lower limb injury wearing a plaster cast. There was no consensus on safe transportation of these patients. No scientific data is available on the dynamics of transportation of patients with lower limb trauma. In order to assess the safest method of transportation an experiment was conducted. Ethical committee approval was granted. Five volunteers wearing above leg plaster casts were placed in a decompression chamber. The effects on anterior compartment pressures, Doppler venous return, ambient pressure between plaster and skin were assessed in different positions with and without plasters being split. In the normal population we have shown a trebling of intracompartmental pressures from an average of under 10mmHg to 30mmHg. Intracompartmental pressures are more raised with 90 degrees of hip flexion rather than 45 degrees. We recommend patients be transferred with their legs at 45 degrees to the ground with a split plaster cast.