Aims. Developmental cervical spinal stenosis (DcSS) is a well-known predisposing factor for degenerative cervical myelopathy (DCM) but there is a lack of consensus on its definition. This study aims to define DcSS based on MRI, and its multilevel characteristics, to assess the prevalence of DcSS in the general population, and to evaluate the presence of DcSS in the prediction of developing DCM. Methods. This cross-sectional study analyzed MRI spine morphological parameters at C3 to C7 (including anteroposterior (AP) diameter of spinal canal, spinal cord, and vertebral body) from DCM patients (n = 95) and individuals recruited from the general population (n = 2,019). Level-specific median AP spinal canal diameter from DCM patients was used to screen for stenotic levels in the population-based cohort. An individual with multilevel (≥ 3 vertebral levels) AP canal diameter smaller than the DCM median values was considered as having DcSS. The most optimal cut-off canal diameter per level for DcSS was determined by receiver operating characteristic analyses, and multivariable logistic regression was performed for the prediction of developing DCM that required surgery. Results. A total of 2,114 individuals aged 64.6 years (SD 11.9) who underwent surgery from March 2009 to December 2016 were studied. The most optimal cut-off canal diameters for DcSS are: C3 < 12.9 mm, C4 < 11.8 mm, C5 < 11.9 mm, C6 < 12.3 mm, and C7 < 13.3 mm. Overall, 13.0% (262 of 2,019) of the population-based cohort had multilevel DcSS. Multilevel DcSS (odds ratio (OR) 6.12 (95% CI 3.97 to 9.42); p < 0.001) and male sex (OR 4.06 (95% CI 2.55 to 6.45); p < 0.001) were predictors of developing DCM. Conclusion. This is the first MRI-based study for defining DcSS with multilevel canal narrowing. Level-specific cut-off canal diameters for DcSS can be used for early identification of individuals at risk of developing DCM. Individuals with DcSS at ≥ three levels and male sex are recommended for close monitoring or early intervention to avoid traumatic spinal cord injuries from stenosis. Cite this article: Bone Joint J 2024;106-B(11):1333–1341

The objectives of the study were to investigate demographic, injury and surgery/treatment-associated factors that could influence clinical outcome, following Autologous Chondrocyte Implantation (ACI) in a large, “real-world”, 20 year longitudinally collected clinical data set. Multilevel modelling was conducted using R and 363 ACI procedures were suitable for model inclusion. All longitudinal post-operative Lysholm scores collected after ACI treatment and before a second procedure (such as knee arthroplasty but excluding minor procedures such as arthroscopy) were included. Any patients requiring a bone graft at the time of ACI were excluded. Potential predictors of ACI outcome explored were age at the time of ACI, gender, smoker status, pre-operative Lysholm score, time from surgery, defect location, number of defects, patch type, previous operations, undergoing parallel procedure(s) at the time of ACI, cell count prior to implantation and cell passage number. The best fit model demonstrated that for every yearly increase in age at the time of surgery, Lysholm scores decreased by 0.2 at 1-year post-surgery. Additionally, for every point increase in pre-operative Lysholm score, post-operative Lysholm score at 1 year increased by 0.5. The number of cells implanted also impacted on Lysholm score at 1-year post-op with every point increase in log cell number resulting in a 5.3 lower score. In addition, those patients with a defect on the lateral femoral condyle (LFC), had on average Lysholm scores that were 6.3 points higher one year after surgery compared to medial femoral condyle (MFC) defects. Defect grade and location was shown to affect long term Lysholm scores, those with grade 3 and patella defects having on average higher scores compared to patients with grade 4 or trochlea defects. Some of the predictors identified agree with previous reports, particularly that increased age, poorer pre-operative function and worse defect grades predicted poorer outcomes. Other findings were more novel, such as that a lower cell number implanted and that LFC defects were predicted to have higher Lysholm scores at 1 year and that patella lesions are associated with improved long-term outcomes cf. trochlea lesions

Objective. To determine the incidence, distribution and associated organ damage in patients that sustained multilevel spinal injuries presenting to a level 1 trauma unit. Is the standard trauma series adequate?. Methodology. A retrospective, chart review of all spinal injury patients that were admitted to the spinal unit from March 2007 to May 2011 was performed. Patients with multilevel spinal injuries were isolated from paediatric, single level, and gunshot injuries. All Trauma unit patients undergo a full body C.T scan with angiography. Using the radiologist's reports the incidence, mechanism of injury, distribution patterns and associated organ damage sustained by this subset of patients was tabulated and reported on. Results. Of the 825 patients that were admitted to the unit, 141 patients had sustained some form of spinal injury. 13 paediatric and 21 gunshot wound spinal patients were excluded. 107 adult blunt force spinal injuries were identified of which 39 fulfilled the multilevel spinal injury criteria. Conclusion. The Incidence of multilevel spinal trauma is higher than previously reported. Distribution patterns found on this C.T scan based study differ from the older x-ray based studies. Distinct patterns of associated organ damage exist with specific spinal injury levels. The dorso- lumbar spine is the most common secondary level involved and it should be included in the trauma series X-ray evaluation of high risk polytrauma patients. NO DISCLOSURES

Abstract. Objectives. Single-event multilevel surgery (SEMLS) is the standard orthopaedic treatment for gait abnormalities in children with diplegic cerebral palsy (CP). The primary aim of this study was to report the long-term functional mobility of these patients after surgery. The secondary aim was to assess the relationship between functional mobility and quality of life (QoL). Methods. Patients were included if they met the following criteria: 1) diplegic CP; 2) Gross Motor Function Classification System (GMFCS) I to III; 3) SEMLS at age ≤ 18. A total of 61 patients, mean age at surgery 11 years eight months (SD 2y 5m), were included. A mean of eight years (SD 3y 10m) after SEMLS, patients were contacted and asked to complete the Functional Mobility Scale (FMS) questionnaire over the telephone and given a weblink to complete an online version of the CP QOL Teen. FMS was recorded for all patients and CP QOL Teen for 23 patients (38%). Results. Of patients graded GMFCS I and II preoperatively, at long-term follow-up the proportion walking independently at home, school/work and in the community was 71% (20/28), 57% (16/28) and 57% (16/28), respectively. Of patients graded GMFCS III preoperatively, at long-term follow-up 82% (27/33) and 76% (25/33) were walking either independently or with an assistive device at home and school/work, respectively, while over community distances 61% (20/33) required a wheelchair. The only significant association between QoL and functional mobility was better ‘feelings about function’ in patients with better home FMS scores (r=0.55; 95% confidence interval 0.15 to 0.79; p=0.01). Conclusion. The majority of children maintained their preoperative level of functional mobility at long-term follow-up after SEMLS. Despite the favourable functional mobility, there was little evidence to establish a link between functional status and quality of life

Children with diplegic cerebral palsy develop progressive musculoskeletal deformities with deterioration in their gait. Multilevel surgery is a well-established treatment modality involving a combination of soft tissue lengthening and correction of bony deformities. At Bristol Royal Children's Hospital we have identified a cohort of 45 children with diplegic cerebral palsy who have undergone multilevel surgery. Video gait analysis had been performed pre-operatively and three years post-operatively. We utilised the Edinburgh Visual Gait Score (EVGS). [1]. , a validated system that allows direct comparison with gait videos taken during different periods of the patient's treatment. Seventeen measurements are taken per limb at each stage. The patients were also categorised according to the Functional Walking Score (FWS) . [2]. that assesses their level of independence. Post-operative results demonstrate a significant improvement in gait score on both the EVGS and FWS. Patients whose gait was more severely affected prior to surgery had the greatest improvement in mobility and functional scores. Patients consistently had significant improvements in hip and knee extension in stance phase, with more modest improvement in knee flexion in swing with persistent co-contraction. Both initial contact and heel lift were consistently abnormal pre-operatively, but few patients achieved a heel strike and normal heel lift post-operatively. We are proceeding with a long-term follow-up of this cohort of patients at 15 years following surgery. The combination of using detailed video gait analysis with functional assessment is a valuable tool in retrospective assessment of patients' outcome following surgery. It gives a quantitative evaluation of progression over time as well as allowing comparison with a cohort of patients to estimate the future level of functional independence

Purpose of Study. In children with spastic diplegia, surgery for equinus has a high incidence of both over and under correction. We wished to determine if conservative (mainly Zone 1) surgery for equinus gait, in the context of multilevel surgery, could result in the avoidance of calcaneus and crouch gait as well as an acceptable rate of recurrent equinus, at medium term follow-up. Description of Methods. This was a retrospective, consecutive cohort study of children with spastic diplegia, between 1996 and 2006. All children had distal gastrocnemius recession or differential gastrocsoleus lengthening, on one or both sides, as part of Single Event Multilevel Surgery. The primary outcome measures were the Gait Variable Scores (GVS) and Gait Profile Score (GPS) at two time points after surgery. Summary of Results. Forty children with spastic diplegia, GMFCS Level II and III were eligible for inclusion in this study. There were 25 boys and 15 girls, mean age 10 years at surgery. The mean age at final follow-up was 17 years and the mean postoperative follow-up period was seven years. The mean ankle GVS improved from 18.5° before surgery to 8.7° at short term follow-up (P<0.005) and 7.8° at medium term follow-up. Equinus gait was successfully corrected in the majority of children with a low rate of over-correction (2.5%) but a high rate of recurrent equinus (35.0%), as determined by sagittal ankle kinematics. Conclusion. Surgery for equinus gait, in children with spastic diplegia, was successful in the majority of children, at a mean follow-up of seven years, when combined with multilevel surgery, orthoses and rehabilitation. No patients developed crouch gait and the rate of revision surgery for recurrent equinus was 12.5%. NO DISCLOSURES

Purpose of the study. To compare safety and efficacy of cervical disc replacement (CRD) in single and multilevel DDD. Patients were followed up at 1, 3, 6, 12 and 24 months. Methods. 249 patients were enrolled. 171 patients were treated at 1-level, 41 treated at 2 levels and 2 patients were treated at 3 levels. Implant was also used adjacent to a fusion with a cage in 35 patients. The diagnosis was cervical degenerative disc disease between C3 and C7 with symptomatic DH. Population was 106 male 143 female, average age 46 (25-71). Clinical assessment included VAS scores for arm and neck pain and Neck Disability Index (NDI). Range of motion (ROM) from flexion/extension lateral view were measured. Results. Of all NDI scores recorded, 86,50 % demonstrated at least 15 points improvement at two years follow up from pre-op scores. 85,1% of VAS arm Pain scores demonstrated an improvement by = 2 points from pre-op scores and 50,8% for VAS neck Pain scores. The breakdown by levels and adjacent to an interbody cage shown that 80% of reported NDI scores demonstrated at least a 15 point improvement post operatively for two level disc replacement. 82,4% demonstrated a greater than 2 points improvement in VAS arm pain and 53,3% for VAS neck pain. For patients that received both implant and an interbody cage, 72,7% demonstrated a greater than 2 point improvement in VAS arm pain and 41,7% for VAS neck pain. Three (1,8%) cases of subsidence and 4 cases of implant loosening/displacement due to inappropriate sizing were reported. Available radiographic findings show on average a ROM of 8,2 ° at 2 years and an overall change in cervical lordosis of 5° from pre-op. Conclusion. Clinical outcomes demonstrated a significant improvement for both the total population (n=249) and for the single level total disc replacement population (n=171). Given these outstanding results single and multilevel TDR with this implant can be considered to be safe. No significant difference was observed between single and multilevel TDR groups regarding clinical, functional and radiological results. Follow up for this series need however to be extended for up to 5 years at least. The role of this implant in multilevel cases as well as in cases to a fused level still need further evaluation although these preliminary results are encouraging

Purpose. To review the outcome of multilevel (≥4) instrumented lumbar fusion to sacrum / pelvis performed for degenerative conditions. Methods. Clinical data of 47 consecutive patients from 2002 to 2012 were reviewed retrospectively. Inclusion criteria included fusion from at least L2 to S1 / pelvis, i.e. minimum of 4 levels. Imaging was assessed for restoration of normal sagittal profile as well as subsequent fusion. EQ5D, OSD and VAS scores pre-op and at 6 months post op were analysed. Average age at surgery was 64 years (50–78). Thirteen cases were primary and 34 revisions. Indications were axial back pain either associated with sagittal imbalance (40%) or leg pain (36%) and leg pain alone in 10%. Results. The intra-operative blood loss averaged 2222 (250–7000) ml with 40% re-infusion from cell-saver. The average surgical duration was 268 minutes. Proximal extent of instrumentation was T2 (1), T3 (1), T4 (2), T8 (1), T9 (1), T10 (17), T11 (2), T12 (5), L1 (4) and L2 (13). TLIF's were done in 20 cases mostly at the base of the construct. Pedicle subtraction osteotomies were performed in 14 revision cases. Dural tears occurred in 14 cases, all revision cases except one. Wound infection occurred in 3 cases. Except for transient quadriceps weakness related to osteotomy, no neurological complications occurred. One patient deceased peri-operatively. Subsequent revision was required in 13 cases for instrumentation failure. OSD score improved by 15.3 points on average, which is clinically and statistically significant. Conclusion. Long lumbar fusions remain technically demanding with a high incidence of adverse events. This is due to the nature of revision surgery and high biomechanical demands on constructs. Surgical intervention can however be justified by the desperation of the cohort in terms of pain and poor function which can be modestly improved with this intervention. NO DISCLOSURES

There are numerous surgical techniques described for cervical decompression for multilevel cervical stenosis. Cervical skip laminectomy is a new technique described by Japanese surgeons in 2000. The advantage of this procedure over the other conventional techniques is it addresses multilevel problem in a least traumatic way without need for instrumentation. It is also described to have lesser incidence of post operative axial symptoms, range of motion and loss of cervical lordosis. We are presenting our prospective case series of 23 patients who had this procedure in our institution between 2002 and 2004. Of these 16 patients are at least 6 months from their operation. We performed clinical outcome measurements using SF12 questionnaires, pre and postoperative clinical assessment performed by independent surgeon and a specialist spinal physiotherapist. We also routinely performed pre and postoperative MRI scans to assess the adequacy of decompression (Done by our musculoskeletal radiologist). Our study showed a good clinical and radiological outcome with this relatively simple new procedure. This has become our standard operation for our patients with multilevel cervical stenosis with cervical myelopathy

Fifty-two patients older than sixty years had undergone multilevel lumbar decompression and fusion with instrumentation and reached a minimum two-year follow up. The relationship between abnormal sagittal plane configuration of the proximal segments and the number of lumbar fusion segments was radiographically analyzed. Group A (L1-L5 or S1) patients had two (20%) proximal vertebral compression fractures and four (40%) focal kyphosis. Group B (L2-L5 or S1) patients had one (6%) proximal vertebral compression fractures, five (33%) retrolisthesis and two (13%) focal kyphosis. Group C (L3-S1) had seven (39%) retrolisthesis. Group D had only one retrolisthesis and two disc height loss. Radiographically analyze the relationship between abnormal sagittal plane configuration of the proximal segments and the number of lumbar fusion segments in patients older than sixty years old. It appears that lumbar fusion up to L1 causes more kyphotic changes and topping off syndrome in the elderly. Fusion L2-L5 or S1 seems having less severe adjacent level degeneration. Retrolisthesis is a significant problem in fusion from L3-L5 or S1. The least adjacent level degenerative changes were seen in L4-S1 fusion. Selected limited instrumentation avoiding kyphotic segments or extending the fusion above the thoracolumbar junction may be the needed. Solid fusion was seen in 46 (88%) patients. There were ten patients in group A, and two (20%) had vertebral compression fractures in the most cranial vertebrae and four (40%) focal kyphosis. Of fifteen patients in group B, one (6%) had compression fracture, five (33%) retrolisthesis, and two (13%) focal kyphosis. Of eighteen patients in group C, retrolisthesis was seen in seven (39%) patients. Group D had nine patients with only one patient having retrolisthesis and two having disc height loss. Since January 1997, there were fifty-two consecutive patients with an average age of seventy years who have undergone multilevel lumbar decompression and posterolateral fusion with pedicle screw-rod instrumentation, and have reached a minimum two-year follow up. Postoperative radiographs of lumbar fusion were classified into group A (L1-L5 or S1), group B (L2-L5 or S1), group C (L3-L5 or S1) and group D (L4-S1)

Introduction: Total en bloc spondylectomy (TES) as the only radical treatment option for sarcoma and solitary metastases of the spine was shown to markedly minimize local recurrences, improve patient quality of life and substantially increase overall survival rates. This study analyzes the onco-surgical results after multilevel thoracolumbar TES and reconstruction with a carbon composite vertebral body replacement system (CC-VBR) in a collective of patients. Methods: 26 patients (14f/12m; age 52±14y) treated with thoracolumbar multilevel TES (10x2, 12x3, 3x4, 1x5 segments) for spinal sarcomas (n=16), solitary metastases (n=5) and aggressive primary tumors (n=5) were retrospectively investigated. According to the classification system of Tomita et al. all patients were surgically staged as type 6 (multisegmental/extracom-partimental). Defect reconstruction (14 thoracic, 6 thoraco-lumbar and 6 lumbar) were performed with posterior stabilization and a CC-VBR. Patient charts and the current clinical follow-up results were analyzed for histopathological tumor type, pre- and postoperative data (symptoms, duration of surgery, blood loss, complications, intensive care, adjuvant therapies etc.) and course of disease. Latest radiographs and CT-scans were analyzed at follow up. Oncological status was evaluated using cumulative disease specific and metastases-free survival analysis. Results: With a mean follow up (100%) of 18 (4–44) months 24 patients (92%) were postoperatively ambulatory without any support. Postoperative neurological deficits were seen in two patient (8%). Wide resection margins were attained in 9, marginal in 17 patients. Depending on tumor biology/grading and/or resections margins an adjuvant therapy (radiation/chemotherapy) was performed in 18 (69%) patients. Local recurrence was found in two patient (8%). 19 (73%) patients showed no evidence of disease, 3 were alive with disease while 2 died of disease at 10 and 27 months postoperatively. Conclusion: In selected patients with multisegmental spinal tumor involvement oncological sufficient resections can be reached by multilevel TES. Although the surgical procedure is challenging and the patient’s stress is considerable our encouraging midterm results together with the low complication rate clearly favour and legitimate this technique. However, treatment success strongly depends on adjuvant therapies. Reconstruction with a CC-VBR showed low complication rates, promising biomechanical characteristics, increased volume for bone grafting and lower artefact rates in follow-up MR- and CT-imaging

Introduction: Total en bloc spondylectomy (TES) as the only radical treatment option for sarcoma and solitary metastases of the spine was shown to markedly minimize local recurrences, improve patient quality of life and substantially increase overall survival rates. Due to surgical difficulty of TES and complex biomechanical demands in defect reconstruction multisegmental tumor involvement of the spine has long been considered as a palliative situation, exceeding the limits of surgical feasibility. Thus, multilevel resections reports are very rare. For the first time, this study analyzes the onco-surgical results after multilevel thoracolumbar TES and reconstruction with a carbon composite vertebral body replacement system (CC-VBR) in a collective of patients. Methods: 18 patients (9f/9m; age 52±14y) treated with thoracolumbar multilevel TES (6x2, 9x3, 3x4 segments) for spinal sarcomas (n=9), solitary metastases (n=5) and aggressive primary tumors (n=3) were retrospectively investigated. According to the classification system of Tomita et al. all patients were surgically staged as type 6 (multisegmental/extracompartimental). Defect reconstruction (11 thoracic, 3 thoracolumbar and 4 lumbar) were performed with posterior stabilization and a CC-VBR. Patient charts and the current clinical follow-up results were analyzed for histopathological tumor type, pre- and postoperative data (symptoms, duration of surgery, blood loss, complications, intensive care, adjuvant therapies etc.) and course of disease. Latest radiographs and CT-scans were analyzed at follow up. Oncological status was evaluated using cumulative disease specific and metastases-free survival analysis. Results: With a mean follow up (100%) of 18 (4–44) months 17 patients (94%) were postoperatively ambulatory without any support. Postoperative neurological deficits were seen in one patient (6%). Wide resection margins were attained in 7, marginal in 11 patients. Depending on tumor biology/grading and/or resections margins an adjuvant therapy (radiation/chemotherapy) was performed in 12 (67%) patients. Local recurrence was found in one patient (6%). 13 (72%) patients showed no evidence of disease, 3 were alive with disease while 2 died of disease at 10 and 27 months postoperatively. Conclusion: In selected patients with multisegmental spinal tumor involvement oncological sufficient resections can be reached by multilevel TES. Although the surgical procedure is challenging and the patient’s stress is considerable our encouraging midterm results together with the low complication rate clearly favour and legitimate this technique. However, treatment success strongly depends on adjuvant therapies. Reconstruction with a CC-VBR showed low complication rates, promising biomechanical characteristics, increased volume for bone grafting and lower artefact rates in follow-up MR- and CT-imaging

Introduction Spondylolysis and isthmic spondylolisthesis (IS) have both a familial and mechanical aetiology, yet the phenotypic expression of the familial aetiology is unknown except for the observation of spinal bifida occulta. Other posterior element abnormalities are unrecognised, and any facet joint orientation (FJO) abnormality at the effected level has been ignored because of presumed previous mechanical defunctioning by the pars defect. The recognition of multilevel sagittal FJO in L4/5 degenerative spondylolisthesis (DS), begs the question whether more proximal segment examination may reveal FJ variations in IS. Methods MRI scans were used to measure orientation of the FJ at L3/4, L4/5, and L5/S1 in 30 individuals with normal scans, and 30 patients with IS. The angular measurement recorded is in relation to the coronal plane. Repeated measures assessment confirmed method validity. Results Mean measurement of axial FJO at L3/4 and L4/5 was 51.1 and 42.5deg in normal subjects, and 45.2 and 35.0deg in IS. The more coronal angulation at the levels above a pars defect in IS was highly statistically significant (p=0.0006 & p=0.00002). At L5/S1 orientations were the same (39deg). Discussion Relative coronal FJO in the lumbar spine may be the phenotypic expression of the congenital aetiology of IS. The mechanism of effect may be increased stress concentration at the pars between or below coronally oriented FJs. These more coronal FJOs in IS also explain:- the common observation of retrolisthesis at L4/5 above IS when the L4/5 disc degenerates, lateral overhang of the L4/5 FJ to the L5 pedicle entry-point above an IS, and the exceptionally uncommon combination of DS at L4/5 and IS at L5/S1 when both disorders are independently common. This latter observation can be further explained by the generalization that DS occurs in those individual with sagittal lumbar facets, and that IS occurs in those with more coronal FJs

Objective

Lumbar spinal stenosis (LSS) is a common spinal disorder mostly caused by the arthritic process. In cases with refractory complaints or significant neurologic deficit, decompressive surgery with or without instrumented fusion may be indicated. We aimed to investigate the surgical outcome of multi-level LSS in the patient with stable spine treated by simple decompression versus decompression and instrumented fusion. Methods: We retrospectively studied 51 patients (25 male, 26 female) with stable multi-level (>2 levels) LSS who were treated by decompressive surgery alone (group A, 31 cases) and decompression and instrumented fusion (group B, 20 cases) and followed them for more than two years. The patients’ disability and pain were assessed with Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS), respectively. At the last follow-up visit, patient satisfaction with surgery was also scored. Results: The two groups were homogeneous in terms of age, sex, severity of disability and pain. Surgery could significantly improve pain and disability in both groups. Preoperative ODI in group A and B were 51.0±23.7 and 54.5±22.9, respectively, however at the last follow-up visit these parameters improved to 23.1±21.1 and 36.6±21.4 showing a statistical significance. Mean patient satisfaction with surgical intervention was also higher in the simple decompression group, but this difference was not significant. Conclusion: In surgical treatment of the patients with multi-level but stable LSS, simple decompression versus decompression and instrumented fusion could achieve more disability improvement for more than two years of follow-up.

Introduction. With the use of each pedicle screw for surgical correction of adolescent idiopathic scoliosis (AIS), there is an increase in instrumentation-related costs, operative time, risk of neural injury, and overall health-care expenses. As such, alternate level screw strategy (ALSS) has been reported as a potential alternative to contiguous multilevel screw strategy (CMSS). Moreover, studies have shown the importance in accounting for the flexibility of the curve based on the fulcrum bending radiograph when assessing postoperative curve correction. Therefore, this study addressed a radiographic and cost analysis comparing CMSS with ALSS for the treatment of thoracic AIS with titanium screws and rod application. Methods. 77 patients with AIS underwent surgery (range 6–15 levels). 35 patients received CMSS, which was characterised as bilateral screw fixation at every level. 42 patients underwent ALSS, which entailed bilateral screw fixation at alternate levels. Titanium rods were used in all cases. Preoperative and postoperative posteroanterior and fulcrum bending radiographic Cobb angles were obtained for all patients. The fulcrum flexibility and the fulcrum bending correction index (FBCI) were assessed. Cost analysis was also done. Results. We recorded a statistically significant difference between screw strategy-type to that of preoperative and postoperative Cobb angles, and postoperative curve correction (p<0·05). No statistically significant difference was noted between screw strategy-type and fulcrum flexibility (CMSS mean 66·9%; ALSS mean 62·7%; p>0·05). The mean FBCIs of the CMSS and ALSS were 126·1% and 122·1%, respectively, and did not differ significantly (p=0·734). Compared with CMSS, ALSS was associated with pedicle screw cost reductions of up to 46·2%. Conclusions. This study is the first to show that irrespective of curve rigidity, ALSS with fewer pedicle screws can achieve comparable FBCI as CMSS. We attribute this finding to the relatively flexible titanium rods used in this study. Thus, ALSS is as effective as CMSS in terms of coronal curve correction, and it has the added benefits of reducing operative time and neurological complication risk. Furthermore, it offers the possibility of better kyphosis restoration compared with the lordosing effect of CMSS

Single level posterolateral spinal fusion in rabbits is the accepted preclinical model for evaluating bone graft substitutes or treatments to enhance/augment healing. This study aimed to improve preclinical testing by developing a multi-level unilateral fusion model that could be used as a screening tool prior to larger scale preclinical experiments.

A four level unilateral posterolateral fusion was performed in nine animals. The materials were randomly allocated and placed between the decorticated surfaces of the transverse processes and vertebral bodies. Animals were euthanised at three, six and 12 weeks. The materials were (1) 25 kGy y-irradiated rabbit allograft chips (RAC), (2) SCF RAC, (3) 60% tri-calcium phosphate, 40% hydroxyapatite formagraft (BiOstetic) (4) Autograft (1.5 cc morsellised to 1-2.5 mm granules). The autograft was harvested from the iliac crest using the L5-L6 incision. Endpoints included x-ray, CT, micro CT and histology.

The animals tolerated the surgery well. Radiographic data provided a useful method to differentiate between groups. Micro CT however was extremely valuable demonstrating new bone formation as early as three weeks across the groups. Gamma irradiated samples demonstrated an initial inflammatory reaction while the autograft, SCF allograft and synthetic TCP did not show this response. As expected, time was an important factor demonstrating the maturity in the fusions. These materials responded in a similar fashion in this model as observed in a single level fusion.

A unilateral multi-level fusion can be performed in rabbits to provide a useful screening for different materials. Gamma irradiated allograft has an initial inflammatory reaction that may be related to the presence of residual cellular material whereas SCF and synthetic materials do not.

Introduction: The purpose of this study was to quantify changes in lower limb muscle strength in children with spastic diplegic cerebral palsy 6 months after multi-level orthopaedic surgery.

Method: A consecutive sample of 20 children ( 10 girls and 10 boys, mean age 10.6) with spastic diplegia was studied prospectively. All participants had soft-tissue and bony surgical procedures performed as part of their clinical management. Physiotherapy treatment commenced following surgery. Lower limb muscle strength, pre and 6 months post-surgery, was measured, in addition to routine gait and function assessment. Maximum voluntary isometric strength of 5 muscle groups was measured bilaterally using a digital dynamometer. Paired-samples t-tests were performed.

Results: There was a marked deterioration of muscle strength (p < 0.05) in all muscle groups. Medial hamstrings and hip flexors showed the greatest decline with an average decrease of 54% and 41% respectively. Analysis of gait parameters showed a significant improvement in kinematics (p< 0.05) but a decrease in walking velocity and cadence. Motor function decreased significantly (p< 0.05). There was reduced motor power in 18 of the 20 at 6 months.

Discussion: Our results quantified objectively the magnitude of strength changes after multi-level surgery and show that weakness may be greater and persist longer than expected. This information will be useful for planning treatment after multi-level surgery and is part of a randomised trial investigating strength training. In general there is a decrease in power but an improvement in gait.

Aims. Cementing in arthroplasty for hip fracture is associated with improved postoperative function, but may have an increased risk of early mortality compared to uncemented fixation. Quantifying this mortality risk is important in providing safe patient care. This study investigated the association between cement use in arthroplasty and mortality at 30 days and one year in patients aged 50 years and over with hip fracture. Methods. This retrospective cohort study used linked data from the Australian Hip Fracture Registry and the National Death Index. Descriptive analysis and Kaplan-Meier survival curves tested the unadjusted association of mortality between cemented and uncemented procedures. Multilevel logistic regression, adjusted for covariates, tested the association between cement use and 30-day mortality following arthroplasty. Given the known institutional variation in preference for cemented fixation, an instrumental variable analysis was also performed to minimize the effect of unknown confounders. Adjusted Cox modelling analyzed the association between cement use and mortality at 30 days and one year following surgery. Results. The 30-day mortality was 6.9% for cemented and 4.9% for uncemented groups (p = 0.003). Cement use was significantly associated with 30-day mortality in the Kaplan-Meier survival curve (p = 0.003). After adjusting for covariates, no significant association between cement use and 30-day mortality was shown in the adjusted multilevel logistic regression (odd rati0 (OR) 1.1, 95% confidence interval (CI) 0.9 to 1.5; p = 0.366), or in the instrumental variable analysis (OR 1.0, 95% CI 0.9 to 1.0, p=0.524). There was no significant between-group difference in mortality within 30days (hazard ratio (HR) 0.9, 95% CI 0.7to 1.1; p = 0.355) or one year (HR 0.9 95% CI 0.8 to 1.1; p = 0.328) in the Cox modelling. Conclusion. No statistically significant difference in patient mortality with cement use in arthroplasty was demonstrated in this population, once adjusted for covariates. This study concludes that cementing in arthroplasty for hip fracture is a safe means of surgical fixation. Cite this article: Bone Jt Open 2023;4(3):198–204

Lateral lumbar interbody fusion (LLIF) has biomechanical advantages due to the preservation of ligamentous structures (ALL/PLL), and optimal cage height afforded by the strength of the apophyseal ring. We compare the biomechanical motion stability of multiple levels LLIF (4 segments) utilising PEEK interbody 26mm cages to stand-alone cage placement and with supplemental posterior fixation with pedicle screw and rods. Six lumbar human cadaver specimens were stripped of the paraspinal musculature while preserving the discs, facet joints, and osteoligamentous structures and potted. Specimens were tested under 5 conditions: intact, posterior bilateral fixation (L1-L5) only, LLIF-only, LLIF with unilateral fixation and LLIF with bilateral fixation. Non-destructive testing was performed on a universal testing machine (MTS Systems Corp) to produce flexion-extension, lateral-bending, and axial rotation using customized jigs and a pulley system to define a non-constraining load follower. Three-dimensional spine motion was recorded using a motion device (Optotrak). Results are reported for the L3-L4 motion segment within the construct to allow comparison with previously published works of shorter constructs (1-2 segments). In all conditions, there was an observed decrease in ROM from intact in flexion/extension (31%-89% decrease), lateral bending (19%-78%), and axial rotation (37%-60%). At flexion/extension, the decreases were statistically significant (p<0.007) except for stand-alone LLIF. LLIF+unilateral had similar decreases in all planes as the LLIF+bilateral condition. The observed ROM within the 4-level construct was similar to previously reported results in 1-2 levels for stand-alone LLIF and LLIF+bilateral. Surgeons may be concerned about the biomechanical stability of an approach utilizing stand-alone multilevel LLIF. Our results show that 4-level multilevel LLIF utilizing 26 mm cages demonstrated ROM comparable to short-segment LLIF. Stand-alone LLIF showed a decrease in ROM from the intact condition. The addition of posterior supplemental fixation resulted in an additional decrease in ROM. The results suggest that unilateral posterior fixation may be sufficient

Aims. The aim of this study was to explore the functional results in a fitter subgroup of participants in the Hip Fracture Evaluation with Alternatives of Total Hip Arthroplasty versus Hemiarthroplasty (HEALTH) trial to determine whether there was an advantage of total hip arthroplasty (THA) versus hemiarthroplasty (HA) in this population. Methods. We performed a post hoc exploratory analysis of a fitter cohort of patients from the HEALTH trial. Participants were aged over 50 years and had sustained a low-energy displaced femoral neck fracture (FNF). The fittest participant cohort was defined as participants aged 70 years or younger, classified as American Society of Anesthesiologists grade I or II, independent walkers prior to fracture, and living at home prior to fracture. Multilevel models were used to estimate the effect of THA versus HA on functional outcomes. In addition, a sensitivity analysis of the definition of the fittest participant cohort was performed. Results. There were 143 patients included in the fittest cohort. Mean age was 66 years (SD 4.5) and 103 were female (72%). No clinically relevant differences were found between the treatment groups in the primary and sensitivity analyses. Conclusion. This analysis found no differences in functional outcomes between HA and THA within two years of displaced low-energy FNF in a subgroup analysis of the fittest HEALTH patients. These findings suggest that very few patients above 50 years of age benefit in a clinically meaningful way from a THA versus a HA early after injury. Cite this article: Bone Jt Open 2022;3(8):611–617