Aims

This study addressed two questions: first, does surgical correction of an idiopathic scoliosis increase the volume of the rib cage, and second, is it possible to evaluate the change in lung function after corrective surgery for adolescent idiopathic scoliosis (AIS) using biplanar radiographs of the ribcage with 3D reconstruction?

Purpose of the study: Variations in patellar height in relation to the trochlea and the joint line can be a cause of pain and instability and limit the range of knee flexion. The Caton and Deschamps index (CDI) was described and validated in a cohort of adult subjects. The purpose of this work was to validate this index and set the reference values in a paediatric population.

Material and methods: Lateral view of the knee were obtained in 300 patients who consulted for minor trauma without ligament or bone injury. Thirty patients, aged 6 to 15 years, were included in each age group (1-year groups). All radiographs were qualified as normal by the radiologist. Two series of measures were made in random order and at an interval of 8 days by two independent observers. The patellar height and the length of the patellar tendon were measured with computer assistance. The interob-server and intraobserver variabilities were determined.

Results: The mean patellar height was 33.39±7.40 mm. The mean length of the patellar tendon was 34.57±67.36 mm. The mean CDI was 1.06±0.21. There was not significant correlation between patient age, height of the patella and length of the patellar tendon. Thus the height of the patella and the length of the patellar tendon increased with age while the CDI was statistically lower in older patients. The height of the patella was identical in the two genders while the patellar tendon was statistically longer in boys. The CDI was statistically higher in boys. Interobserver and intraobserver agreement was excellent.

Discussion: CDI is a simple and reproducible measurement in adults and in children and adolescents. During growth, it is an alternative to the Insall index which has limited reproducibility and the Koshino index which is difficult to use in routine clinical situations. We found a correlation between CDI and children’s age, related to progressive ossification of the patella.

Conclusion: The CDI is a tool which can be used in routine practice to study patellofemoral problems in the paediatric population as long as the physiological values are weighted by age.

Purpose: To evaluate the long term clinical outcomes as well as radiological changes in distal unfused mobile segments and to evaluate factors that may predispose to distal disc degeneration and/or poor outcome.

Method: 151 mobile segments in 85 patients (65 female), mean age 43.2 (range 21–68), were studied. Curve type, number of fused levels and pelvic incidence were recorded. Clinical outcome was measured using the Whitecloud function scale and disc degeneration using the UCLA disc degeneration score. Spinal balance, local segmental angulations and lumbar lordosis were measured pre- and post-operatively as well as at the most recent follow up – mean 9.3 years (range 7–19).

Results: 62% of patients had a good or excellent outcome. 11 had a poor outcome of which 10 underwent extension of fusion – 5 for pain alone, 3 pain with stenosis and 2 pseudarthroses. Pre-operative disc degeneration was often asymmetric and was slightly greater in older patients. Overall, there was a significant deterioration in disc degeneration (p< 0.0001) that did not correlate with clinical outcome. Disc degeneration correlated with the recent sagittal balance (Anova F=14.285, p< 0.001) and the most recent lordosis (Anova F=4.057, p=0.048). The post-operative sagittal balance and local L5-S1 sagittal angulation correlated to L4 and L5 degeneration respectively. There was no correlation between degeneration and age, pre-operative degenerative score, pelvic incidence, sacral slope, number of fused levels or distal level of fusion.

Conclusion: Disc degeneration does occur below an arthrodesis for scoliosis in adults which does not correlate with clinical outcome. The correlation of loss of sagittal balance with disc degeneration may be as a result of degeneration causing the loss of balance or vice versa i.e. sagittal imbalance causing degeneration. Immediate post-operative imbalance correlates with degeneration of the L4/5 disc, which may imply the latter.

Purpose: To evaluate the indications, outcome, risk factors and complications of transpedicular osteotomy (TPO) in revision scoliosis surgery

Methods: We evaluated patients undergoing TPO for revision scoliosis surgery at our institution between 1989 and 2004 with a minimum follow up of 18 months. Demographic data, anaesthetic risk factors, peri-operative data and complications were recorded. Radiographs pre-operatively, post-operatively and at last follow up recorded sagittal balance, coronal balance, lumbar lordosis and pelvic parameters. Functional outcome was measured using the Whitecloud score.

Results: 21 patients (24 TPO’s) mean age 48.7 years with mean follow up 4.4 years fulfilled criteria for study. All cases had fixed sagittal imbalance pre-operatively. Mean operative time was 4.6 hours and mean transfusion requirement was 2.3. units. A significant improvement (p< 0.03) in sagittal imbalance was gained (although in 3 cases of pseudarthroses this was partially lost) and the post-operative lumbar lordosis correlated closely significantly pelvic incidence (p< 0.03). Functional outcome was good/excellent in 67% cases.

We report 28 complications. 22 early included 4 dural tears, cardiac decompensation with reduction, 5 neurological deficits including a parpaplegia secondary to haematoma which was evacuated and the patient made a good recovery at 6 months, 2 UTIs, IVI infection, superficial wound infection and extension of metalwork due to early proximal decompensation. Late complications included infection (8 years), removal of prominent metalwork, radiculopathy due to screw (6 months) and 3 pseudarthroses. There was no statistically significant correlation of complication with weight, ASA grade or smoking.

Conclusion: TPO in revision scoliosis is an effective method of correcting both coronal and sagittal imbalance but is not without complication, although good functional outcome is achieved in most patients. It is important to consider pelvic parameters pre-operatively to plan the level and magnitude of TPO required.

Purpose of the study: Appropriate surgical treatment for severe lumbosacral spondylolisthesis remains a subject of controversy. Correction of the anterior displacement of L5 and the lumbosacral kyphosis is considered dangerous because of the risk of neurological complications. We present a consecutive series of 40 patients who were treated with the Padovani double plate method for high-grade spondylolisthesis. The long-term outcome was assessed. The reasons for abandoning this method were also discussed.

Material and methods The files of 40 patients (15 boys and 25 girls, aged 8–20 years) underwent surgery in our center from 1979 to 1996. All presented anterior displacement of L5 greater than 50%. After release of the L5 and S1 roots via a posterior approach and insertion posteriorly to anteriorly of two anchors in the S1 body, correction of the L5 displacement was achieved via a transperitoneal anterior approach using a plate applied to the anterior surface of L5 and progressively bolted to the S1 anchors. Clinical and radiological outcome was assessed. Spineview was used for angle measurements. The Beaujon and Japanese Ortopaedic Association scores were used for the clinical assessment.

Results: Lumbosacral fusion was achieved in all patients with complete correction of the L5 displacement in 38. A postoperative radicular deficit was noted in twelve patients and resolved completely in ten. Six patients experienced progressive destabilization of the L4–L5 level. Deep infections in contact with implanted material were noted in five patients. At 18 years mean follow-up, 35 patients are symptom free.

Discussion: This technique enables excellent correction of the L5 displacement and an excellent rate of fusion. The method is particularly challenging technically and the rate of complications is high. Reduction of the displacement appears to be associated with numerous radicular deficits, even after prior release. The plate which was rather large for the youngest patients led to lesions of the L4–L5 disc and destabilization of the suprajacent levels.

Conclusion: Although this technique enables optimal and definitive correction of the lumbosacral deformation, the high rate of complications has led us to change our strategy for the treatment of high-grade lumbosacral spondylolisthesis.

Purpose of the study: The posterior paraspinal approach to the lumbar spine was initially described and promoted by Wiltse for posterolateral arthrodesis of the lumbosacral junction in patients with spondylolisthesis. Despite technical improvements proposed by Wiltse, the muscular cleavage is still poorly localized in the sacrospinalis muscle. The purpose of this work was to provide a more accurate anatomic description of this spinal approach and to describe anatomic landmarks to facilitate execution of the procedure.

Material and methods: Fifty anatomic specimens were dissected (27 male and 23 female cadavers); 33 had been embalmed. The anatomy study used a bilateral approach to the spine. The exact anatomic localization of the muscle cleavage was noted. Measures were taken in relation to the mid line of the L4 spinatus process.

Results: In all specimens, the muscle cleavage lay between the multifidus and longissimus heads of the sacrospinalis muscle. A fibrous partition was noted in 88 of the 100 specimens. The mean distance from the mid line to the cleavage line was 4.04 cm (range 2.4–7.0 cm). The surface of the sacrospinalis muscle presented fine perforating arteries and veins in all specimens, directly in line with the cleavage plane. In 12 cases, a major posterior sensorial branch of the L3 nerve running to the skin was identified in the cranial portion of the approach.

Discussion: The muscle cleavage plane appears to be easy to localize for the paraspinal approach to the lumbosacral junction. Opening the aponeurosis of the latissimus dorsi near the mid line enables visualization of the perforating vessels in line with the anatomic cleavage plane of the sacrospinalis muscle. In our experience, this plane is situated on average 4 cm from the mid line. Hemostasis of these vessels is acceptable since the sacrospinalis muscle has a rich supply of anastomosed vessels. Care must be taken to avoid injury to the posterior sensorial branch of the L3 nerve which runs along the plane of the muscle cleavage.

Conclusion: In our opinion, this minimally hemorrhagic approach is perfectly adapted to non-instrumented fusion of the lumbosacral junction, particularly for spondylolisthesis in children and adults. Precise knowledge of the anatomy of this approach is a necessary prerequisite for successful execution.

Purpose of the study: Experimentally, posterolateral fusion only allows incomplete control of flexion/extension, rotation and lateral inclination. This defect of posterolateral fusion is most marked with there is a wide anterior gap. For certain authors, this situation justifies use of intersomatic arthrodesis. The purpose of this work was to evaluate, within a spinal segment immobilized by posterolateral fusion, the changes observed in disc height and the possible clinical and radiographic impact of a change in disc height.

Material and methods: This was a retrospective analysis of a consecutive series of patients who underwent posterolateral fusion from January 1999 through December 2003 performed in addition to radicular release for degenerative spondylolisthesis were included. Functional symptoms were noted using: VAS, Beaujon function scale, Beaujon self-administered questionnaire, satisfaction scale, GHA28 anxiety/depression scale, and SF36 quality of life questionnaire. Spineview® was applied at the olisthesic level (disc height, listhesis, anglulation), at adjacent levels, for pelvic parameters, sagittal tilt, and vertebral motion on stress views. We searched for a correlation between the consequences of changes in these variables was and the functional outcome as well as the quality of the fusion. The effect of variations in the following preoperative variables was studied with multivariate analysis: disc height, intervetebral angulaion, listhesis, vertebral motion, sagittal balance, use of osteosynthesis or not.

Results: Forty patients were reviewed with a mean follow-up of 38 months (range 15–70 months). Decreased disc height at the olithesic level was associated with local kyphosis. The level above tended towards lordosis while the level below towards kyphosis. These variations had no effect on the final functional outcome.

Discussion: No formal argument could be found in the literature favoring the use of intersomatic arthrodesis to complete posterolateral fusion for the treatment of degenerative spondylisthesis. Disc height is lost after isolated posterolateral fusion with a risk of local kyphosis and persistent intervertebral motion, but these effects do not appear to influence the functional outcome nor the rate of fusion. More than disc height, it would appear that sagittal balance should be preserved to improve functional outcome.

Conclusion: This study enabled us to observe, as is reported in the literature, decreased disc height after posterolateral fusion for degenerative spondylolisthesis. However, there appears to be no correlation between this decreased disc height and the functional outcome. More than disc height, sagittal balance appears to be the determining factor.