Acetabular component positioning is commonly referenced with the pelvis in the supine position in direct anterior approach THA. Changes in pelvic tilt (PT) from the pre-operative supine to the post-operative standing positions have not been well investigated and may have relevance to optimal acetabular component targeting for reduced risk of impingement and instability. The aims of this study were therefore to determine the change in PT that occurs from pre-operative supine to post-operative standing, and whether any factors are associated with significant changes in tilt ≥13° in posterior direction. 13° in a posterior direction was chosen as that amount of posterior rotation creates an increase in functional anteversion of the acetabular component of 10°. 1097 THA patients with pre-operative supine CT and standing lateral radiographic imaging and 1 year post-operative standing lateral radiographs (interquartile range 12–13 months) were reviewed. Pre-operative supine PT was measured from CT as the angle between the anterior pelvic plane (APP) and the horizontal plane of the CT device. Standing PT was measured on standing lateral x-rays as the angle between the APP and the vertical line. Patients with ≥13° change from supine pre-op to standing post-op (corresponding to a 10° change in cup anteversion) were grouped and compared to those with a <13° change using unpaired student's t-tests. Mean pre-operative supine PT (3.8±6.0°) was significantly different from mean post-operative standing PT (−3.5±7.1°, p<0.001), ie mean change of −7.3±4.6°. 10.4% (114/1097) of patients had posterior PT changes ≥13° supine pre-op to standing post-op. A significant number of patients, ie 1 in 10, undergo a clinically significant change in PT and functional anteversion from supine pre-op to standing post-op. Surgeons should be aware of these changes when planning component placement in THA

The spinopelvic alignment is often assessed via the Pelvic Incidence-Lumbar Lordosis (PI-LL) mismatch. Here we describe and validate a simplified method to evaluating the spinopelvic alignment through the L1-Pelvis angle (L1P). This method is set to reduce the operator error and make the on-film measurement more practicable. 126 standing lateral radiographs of patients presenting for Total Hip Arthroplasty were examined. Three operators were recruited to label 6 landmarks. One operator repeated the landmark selection for intra-operator analysis. We compare PI-LL mismatch obtained via the conventional method, and our simplified method where we estimate this mismatch using PI-LL = L1P - 90°. We also assess the method's reliability and repeatability. We found no significant difference (p > 0.05) between the PI-LL mismatch from the conventional method (mean 0.22° ± 13.6) compared to L1P method (mean 0.0° ± 13.1). The overall average normalised root mean square error (NRMSE) for PI-LL mismatch across all operators is 7.53% (mean -3.3° ± 6.0) and 6.5% (mean -2.9° ± 4.9) for the conventional and L1P method, respectively. In relation to intra-operator repeatability, the correlation coefficients are 0.87 for PI, 0.94 for LL, and 0.96 for L1P. NRMSE between the two measurement sets are PI: 9.96%, LL: 5.97%, and L1P: 4.41%. A similar trend is observed in the absolute error between the two sets of measurements. Results indicate an equivalence in PI-LL measurement between the methods. Reproducibility of the measurements and reliability between operators were improved. Using the L1P angle, the classification of the sagittal spinal deformity found in the literature translates to: normal L1P<100°, mild 100°<L1P<110°, and severe L1P>110°. Surgeons adopting our method should expect a small improvement in reliability and repeatability of their measurements, and a significant improvement of the assessment of the mismatch through the visualisation of the angle L1P

This matched cohort study aims to (a) assess differences in spinopelvic characteristics of patients having sustained a dislocation following THA and a control THA group without dislocation; (b) identify spinopelvic characteristics associated with risk of dislocation and; (c) propose an algorithm to define the optimum cup orientation for minimizing dislocation risk. Fifty patients with a history of THA dislocation (29 posterior-, 21 anterior dislocations) were matched for age, gender, body mass index, index diagnosis, and femoral head size with 100 controls. All patients were reviewed and underwent detailed quasi-static radiographic evaluations of the coronal- (offset; center-of-rotation; cup inclination/anteversion) and sagittal- reconstructions (pelvic tilt, pelvic incidence, lumbar lordosis, pelvic-femoral-angle, cup ante-inclination). The spinopelvic balance (PI-LL), combined sagittal index (CSI= Pelvic-femoral-angle + Cup Anteinclination) and Hip-User-Index were determined. sagittal index (CSI= Pelvic-femoral-angle + Cup Anteinclination) and Hip-User-Index were determined. Parameters were compared between the two groups (2-group analysis) and between controls and per direction of dislocation (3-group analysis). There were marginal coronal differences between the groups. Sagittal parameters (lumbar-lordosis, pelvic-tilt, CSI, PI-LL and Hip-User-Index) differed significantly. PI-LL (>10°) and standing pelvic tilt (>18°) were the strongest predictors of dislocation risk (sensistivity:70%/specificity:70%). All hips with a standing CSI<195° dislocated posteriorly and all with CSI>260° dislocated anteriorly. A CSI between 200–245° was associated with significantly reduced risk of dislocation (OR:6; 95%CI:2.5–15.0; p<0.001). In patients with unbalanced and/or rigid lumbar spine, standing CSI of 215–245° was associated with significantly reduced dislocation risk (OR:10; 95%CI:3.2–29.8; p<0.001). PI-LL and standing pelvic-tilt determined from pre-operative, standing, lateral spinopelvic radiograph can be useful screening tools, alerting surgeons of patients at increased dislocation risk. Measurement of the pelvic-femoral angle pre-operatively provides valuable information to determine the optimum, cup orientation associated with reduced dislocation risk by aiming for a standing CSI of 200–245°

Aim: This study presents analysis of the largest case series to date in the published literature of patients with Hurler Syndrome, to identify the severity of thoraco-lumbar kyphosis, risk factors for progression and results of intervention. Methods and Results: Forty two patients with MPS-I had treatment with Bone-marrow transplantation and/ or enzyme replacement therapy between June 1995 and October 2007. These patients had regular systematic clinical review and were seen at least annually. Standing lateral radiographs of the thoracolumbar spine were retrieved and analysed. At initial examination (average age 1y 1m) the thoracolumbar kyphosis measured a mean of 39.6 degrees (SD 12 degrees). Analysis of non-operatively treated patients revealed that patients with an initial kyphosis angle (average age 1y 2m) of less than 40 degrees were significantly less likely to develop progressive kyphosis over the average follow-up period of 3.5 years (mean initial angle 30 degrees and at final follow-up 34 degrees) than those with an angle greater than 40 degrees (mean angle initially 46 degrees and at final follow-up 61 degrees), p=0.005 (repeated measures ANOVA). Seven patients underwent surgical intervention at mean age of 3 years for progressive deformity with favourable results. Conclusion: Thoracolumbar kyphosis is of variable severity in Hurler’s syndrome and patient’s who present with a kyphosis angle of greater than forty degrees on initial radiographic examination are significantly more likely to develop progressive kyphosis. Ethics approval: None. Interest Statement: None

Introduction. Spinopelvic parameters describe the orientation, shape, and morphology of the spine and pelvis. In children without spinal deformity, these parameters change during the first 10 years of life; however, spinopelvic parameters need to be defined in children with significant early-onset scoliosis (EOS). The purpose of this study is to examine the effects of EOS on sagittal spinopelvic alignment. We hypothesise that sagittal spinopelvic parameters for patients with EOS will differ from age-matched children without spinal deformity. These values will act as a baseline for future studies and may predict postoperative complications such as proximal junctional kyphosis and implant failure in children being treated with growing systems. Methods. Standing, lateral radiographs of 82 untreated patients with EOS with Cobb angle greater than 50° were evaluated. Sagittal spine parameters (sagittal balance, thoracic kyphosis [TK], lumbar lordosis [LL]) and sagittal pelvic parameters (pelvic incidence [PI], pelvic tilt [PT], sacral slope [SS], and modified pelvic radius angle [PR]) were measured. These results were compared with those reported by Mac-Thiong and colleagues (Spine, 2004) for a group of similar aged children without spinal deformity. Results. Patients had a mean age of 5·17 years and mean Cobb angle of 73·3° (□}17·3°). Mean sagittal spine parameters were: sagittal balance (+2·4 cm [□}4·03]), TK (38·2° [□}20·8°]), and LL (47·8° [□}17·7°]). These values were similar to those reported for asymptomatic patients (table). Mean sagittal pelvic parameters were: PI (47·1° [□}15·6°]), PT (10·3° [□}10·7°]), SS (35·5° [□}12·2°]), and PR (57·1° [□}21·2°]). Although PI was similar to age-matched controls, PT was significantly higher and there was a trend for lower SS in the study population. Conclusions. Sagittal plane spine parameters in children with EOS were similar to those in children without spinal deformity. Pelvic parameters (PI, SS, PR) were similar between groups; however, children with EOS had signs of pelvic retroversion (increased pelvic tilt)

Introduction. Spinopelvic parameters describe the orientation, shape, and morphology of the spine and pelvis. These parameters change during the first 10 years of life in children without spinal deformity; however, spinopelvic parameters have yet to be defined in children with significant early-onset scoliosis (EOS). Sagittal plane alignment could affect the natural history and outcome of interventions for EOS. As a result, spinopelvic parameters are being defined for this population. On the basis of the landmarks used for measurement of these parameters, there may be inherent error in performing these measurements on the immature pelvis. The purpose of this study is to define the variability associatedwith the measurement of spinopelvic parameters in children with EOS. Methods. Standing, lateral radiographs of 11 patients with untreated EOS were evaluated. Sagittal spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], sacral slope [SS], and modified pelvic radius angle [PR]) were measured. To assess intraobserver reliability, these measurements were repeated 15 days apart. To define interobserver reliability, radiographs were measured by 2 independent observers. Results. Average age was 5·7 years and average Cobb angle was 80·8°. Repeated measurements by one observer showed no significant differences for any of the parameters. Paired samples correlations showed a moderate correlation between measurements of PI (0·564), whereas stronger correlations were demonstrated for measurements of PT (0·816), SS (0·947), and PR (0·789). Interobserver analysis showed a significant difference in measurement of SS (p=0·003), whereasmeasurements of PI, PT, and PR did not differ significantly between independent observers. Conclusions. Intraobserver variabilty yielded acceptable correlations for PT, SS, and PR; however, we noted only a moderate correlation for PI. Interobserver analysis showed a significant difference only in SS. The intraobserver and interobserver variablity of measurements for PT and PR were superior than were those for PI and SS. This finding may be related to difficulties in determining the orientation of the sacral endplate in the immature pelvis when measuring PI and SS

Minimal-invasive augmentation techniques have been advocated to treat osteoporotic vertebral body fractures (VBFs). Kyphoplasty is designed to address both fracture-related pain as well as the kyphotic deformity usually associated with the fracture. Previous studies have indicated the potential of the technique for immediate pain relief and reduction of vertebral height, but whether this is a lasting effect, has not been well investigated. The current prospective study reports on our experience and the one-year results in 27 kyphoplasty procedures in 24 patients with PMMA for osteoporotic VBFs. Pain was assessed on a 0–10 VAS. Deformity and reduction of the vertebral body was measured as the angulation between the two endplates on standing lateral radiographs. All parameters were taken pre-op, one day and two months post-operatively and after one year. Multiple regression analysis was conducted to determine the importance of independent factors as predictors of the achieved fracture reduction. All but one patient experienced pain relief directly following the procedure with a lasting effect after 2 months and also one year in 25 cases. An average vertebral kyphosis reduction of 47.7% was achieved with no loss of reduction after one year. Pain relief was not related to the amount of reduction. The potential for reduction was related to pre-op kyphosis, level treated, and fracture age, but not to the age of the patient. In this series, kyphoplasty was an effective treatment of VBFs in terms of pain relief and durable reduction of deformity. However, whether spinal realignment results in an improved long-term clinical outcome remains to be investigated

Purpose. Spinopelvic parameters describe the orientation, shape, and morphology of the spine and pelvis. In children without spinal deformity, these parameters have been shown to change during the first ten years of life; however, spinopelvic parameters have yet to be defined in children with significant Early Onset Scoliosis (EOS). The purpose of this study is to examine the effects of EOS on sagittal spinopelvic alignment. Method. Standing, lateral radiographs of 82 untreated patients with EOS greater than 50 degrees were evaluated. Sagittal spine parameters (sagittal balance, thoracic kyphosis (TK), lumbar lordosis (LL)) and sagittal pelvic parameters (pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), modified pelvic radius angle (PR)) were measured. These results were compared to those reported by Mac-Thiong et al (Spine, 2004) for a group of asymptomatic (i.e. without spinal deformity) children of similar age. Results. These patients had a mean age of 5.17 years and mean scoliosis of 73.3 17.3. Mean sagittal spine parameters were: sagittal balance (+2.4 4.03 cm), TK (38.2 20.8), and LL (47.8 17.7). These values were similar to those reported for asymptomatic subjects. Mean sagittal pelvic parameters were measured for PI (47.1 15.6), PT (10.3 10.7), SS (35.5 12.2), and PR (57.1 21.2). Although PI was similar to age-matched normals, PT was significantly higher and SS trended lower in the study population. Conclusion. Sagittal plane spine parameters in children with EOS were similar to those found in children without spinal deformity. Likewise, pelvic parameters (PI, SS, PR) were similar; however, those children with EOS signs of pelvic retroversion (increased pelvic tilt). This data may be useful as a baseline in determining prognosis for children with EOS who are treated with growing systems

Purpose: To determine the reliability of six measurement techniques for lumbosacral kyphosis. Method: Using custom computer software, four raters evaluated 60 standing lateral radiographs of the lumbosacral spine during two sessions at a one week interval. The sample size consisted of 20 normal, 20 low and 20 high grade spondylolisthetic subjects. Six parameters were included for analysis: Boxall’s slip angle; Dubousset’s lumbosacral angle (LSA); the Spinal Deformity Study Group’s (SDSG) LSA; dysplastic SDSG LSA; sagittal rotation (SR); kyphotic Cobb angle (k-Cobb). Intra- and inter- rater reliability for all parameters was assessed using intra-class correlation coefficients (ICC). Correlations between parameters and slip percentage were evaluated with Pearson coefficients. Results: The intra-rater ICC’s for all the parameters ranged between 0.81 and 0.97 and the inter-rater ICC’s were between 0.74 and 0.98. All parameters except sagittal rotation showed a medium to large correlation with slip percentage. Dubousset’s LSA and the kyphotic Cobb angle showed the largest correlations (r=−0.78 and r=−0.50, respectively). Sagittal rotation was associated with the weakest correlation (r=−0.10). All other parameters had medium correlations with percent slip (r=0.31 to 0.43). Conclusion: All measurement techniques provided substantial to almost perfect inter- and intra- rater reliability. Dubousset’s LSA showed the strongest correlation with slip grade. However, this parameter does not reflect the local dysplastic changes that occur in lower L5 and upper S1 endplates. A longitudinal study evaluating the best suited parameter for predicting the risk of progression and response to surgical treatment is warranted

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

The purpose was to assess the effect of the posterior slope on the long-term outcome of unicompartmental arthroplasty in knees with intact and deficient anterior cruciate ligaments. We retrospectively reviewed ninety-nine unicompartmental arthroplasties after a mean duration of follow-up of sixteen years (12 to 20 years). At the time of the arthroplasty, the anterior cruciate ligament was considered to be normal in fifty knees, damaged in thirty-one, and absent in eighteen. At the most recent follow-up, we measured the posterior tibial slope and the anterior tibial translation on standing lateral radiographs. In the group of seventy-seven knees that had not been revised by the time of the most recent follow-up, there was a significant linear relationship between anterior tibial translation (mean, 3.7 mm) and posterior tibial slope (mean, 4.3) (p = 0.01). The mean posterior slope of the tibial implant was significantly less in the group of seventy-seven knees without loosening of the implant than it was in the group of seventeen knees with loosening of the implant (p = 0.03). Five ruptures of the anterior cruciate ligament occurred in knees in which the ligament had been considered to be normal at the time of implantation; the posterior tibial slope in these five knees was greater than 13 degrees. Clinical evaluation revealed normal or nearly normal anteroposterior stability at the time of the most recent follow-up in all sixty-six unrevised knees in which the anterior cruciate ligament had been present at the time of implantation. Of the eighteen knees in which the anterior cruciate ligament had been absent at the time of the arthroplasty, eleven still had the implant in situ at the time of the most recent follow-up; the mean posterior tibial slope in these 11 knees was less than 5 degrees. Seven knees in which the anterior cruciate ligament had been absent at the time of the arthroplasty were revised. In these 7 knees, the tibial prosthesis was implanted with a posterior slope greater than 8 degrees. These findings suggest that more than 7 degrees of posterior slope of the tibial implant should be avoided, particularly if the anterior cruciate ligament is absent at the time of implantation. An intact anterior cruciate ligament, even when partly degenerated, was associated with the maintenance of normal anteroposterior stability of the knee for an average of sixteen years following unicompartmental knee arthroplasty

Study Design: The effect of Total Hip Replacement surgery (THR) upon spinal sagittal alignment and low back pain was assessed in patients with severe hip osteoarthritis. Summary of Background Data: Osteoarthritis in the hip joint is associated with abnormal posture and gait due to hip flexion contracture and hip pain. This in turn may cause abnormal spinal sagittal alignment and secondarily induce low back and leg pain. However, there have been no reports regarding the corrective effect of Total Hip Replacement surgery upon spinal sagittal alignment in patients with osteoarthritis of the hip. Methods: This study prospectively analyzed the results of 25 patients (15 females and 10 males, average age 67.4 years (32–84)) undergoing THR for severe osteoarthritis of the hip. Pre and post-surgical assessment included; sagittal measurement of Sacral Inclination (SI) and total Lumbar Lordosis (L1-S1) on standing lateral radiographs. Functional clinical outcomes for hip as well as low back were also evaluated using the Oswestry back Questionnaire, the Modified Harris Hip Score and Visual Analog Scale for lower back pain and hip pain accordingly. All the radiographic and clinical evaluations were completed both before THR surgery and 3 months following the surgery during routine follow up. Results: Mean Lumbar Lordosis before the surgery and in the follow up was 50.36 and 50.32 respectively. Mean sacral inclination before and after surgery were 39.06 and 38.16 respectively. Mean Functional outcomes as assessed by the HHS score before and after the surgery were 45.74 and 81.8 respectively. Mean Oswestry Questionnaire scores before and after the surgery were 36.72 and 24.08 respectively. Mean VAS scores for hip pain before and after the surgery were 7.08 and 2.52 respectively. Mean VAS scores for lower back pain before and after the surgery were 5.04 and 3.68 respectively. Discussion: No Significant difference was found between the sagittal alignment of the spine before THR and 3 months following it. Interestingly, total hip replacement surgery significantly improved spinal functional outcome as well as relieved low back and hip pain

Spinopelvic mobility describes the change in lumbar lordosis and pelvic tilt from standing to sitting position. For 1° of posterior pelvic tilt, functional cup anteversion increases by 0.75° after total hip arthroplasty (THA). Thus, spinopelvic mobility is of high clinical relevance regarding the risk of implant impingement and dislocation. Our study aimed to 1) determine the proportion of OA-patients with stiff, normal or hypermobile spino-pelvic mobility and 2) to identify clinical or static standing radiographic parameters predicting spinopelvic mobility. This prospective diagnostic cohort study followed 122 consecutive patients with end-stage osteoarthritis awaiting THA. Preoperatively, the Oxford Hip Score, Oswestry Disability Index and Schober's test were assessed in a standardized clinical examination. Lateral view radiographs were taken of the lumbar spine, pelvis and proximal femur using EOS© in standing position and with femurs parallel to the floor in order to achieve a 90°-seated position. Radiographic measurements were performed for the lumbar lordosis angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI) and pelvic-femoral-angle (PFA). The difference in PT between standing and seated allowed for patient classification based on spino-pelvic mobility into stiff (±30°). From the standing to the sitting position, the pelvis tilted backwards by a mean of 19.6° (SD 11.6) and the hip was flexed by a mean of 57° (SD 17). Change in pelvic tilt correlated inversely with change in hip flexion. Spinopelvic mobility is highly variable in patients awaiting THA and we could not identify any clinical or static standing radiographic parameter predicting the change in pelvic tilt from standing to sitting position. In order to identify patients with stiff or hypermobile spinopelvic mobility, we recommend performing lateral view radiographs of the lumbar spine, pelvis and proximal femur in all patients awaiting THA. Thereafter, implants and combined cup inclination/anteversion can be individually chosen to minimize the risk of dislocation. No predictors could be identified. We recommend performing sitting and standing lateral view radiographs of the lumbar spine and pelvis to determine spinopelvic mobility in patients awaiting THA

In scoliosis, it is well known that lateral deformity is coupled with vertebral axial rotation. Coupled motion in the sagittal plane, however, has not been investigated. Objective: To investigate the behavior of the sagittal alignment changes when coronal deformity was corrected in idiopathic thoracic scoliosis. Method: 36 idiopathic scoliosis patients with thoracic curves were examined before surgery. Coronal deformity was corrected using the Fulcrum Bending technique1, and biplane radiographs were taken to monitor the correction of the deformity, as well as the coupled sagittal alignment changes. Sagittal alignment was measured from T4/T5 to T12 using Cobb’s method. Difference of less or equal to 3 degrees between two measurements was treated as no change. Results were compared with those measured from standing lateral radiographs prior to and at 1 week after surgery (Posterior correction and fusion with ISOLA: n=15; CD-Horizon: n=8; Moss-Miami: n=11, USS: n=2). Pearson correlation was used for statistical analysis. Results: (A) When scoliosis was corrected under fulcrum bending, the coupled changes in the thoracic kyphosis were decreased if it was greater than 20 degrees (n= 18), increased if less than 20 degrees (n= 2), and kept no change if it was around 20 degrees (n= 16). These changes were not related to the amount of deformity or flexibility in the coronal plane (Table I). (B) There was strong relationship between the sagittal alignment measured on the pre-operative fulcrum bending and postoperative lateral radiographs (P< 0.01). However, the final sagittal alignment was neither correlated with the magnitude or flexibility of the coronal deformity, nor the instrumentation applied (P> 0.05). Discussion: A coupling exists between the coronal lateral deformity and the sagittal alignment in thoracic scoliosis. It seems that the sagittal alignment in a scoliotic spine tends to “normalize” with correction of the deformity: a “hyper-kyphotic” spine tends to reduce, and a “hypo-kyphotic” one tends to increase the kyphosis. Post-operative sagittal alignment seems to be decided by the coupling motion and the amount of curvature of the pre-bent rod, as neither the nature (degree or flexibility or curve pattern) of the coronal deformity nor the choice of instrumentation were related to the post-operative sagittal alignment

Our study aims were to establish correlations between the incidence of patellofemoral pain and clinical, functional and radiographic outcomes in Total Knee Arthroplasty (TKR), using the Duracon prosthesis without patella resurfacing. A consecutive cohort of 52 patients (71 knees) were reviewed at a special follow up clinic at a mean of 29 months. All operations were carried out by a single surgeon or under his direct supervision using a standard procedure. Patients were evaluated clinically and asked directly if they had anterior knee pain. American Knee Society Scores (AKSS) and knee alignment were assessed and patients completed SF-12 and WOMAC questionnaires. Standardised 45 degree skyline and standing lateral radiographs were taken and assessed by a single blinded observer, and patella tilt and displacement measured using Gomes’ method, and patella height measured using the Insall-Salvati ratio. Knees with patellofemoral pain underwent triple phase bone scintigraphy using Technetium 99m-MDP with vascular, blood pool and static (3 hour) imaging. Significant patellofemoral pain was identified in 8 knees (11%), in 6 patients. This group had a reduced mean AKSS compared to knees without patellofemoral pain, although 50% still had a good to excellent outcome as judged by the AKSS. Only 2 knees with patellofemoral pain had abnormal alignment (2 and 12 degrees valgus). The mean SF-12 and WOMAC scores did not differ significantly between knees with patellofemoral pain and those without. Patella tilt and displacement were a common finding in this cohort, and could be as great as 17 degrees and 30% respectively without patellofemoral dysfunction. Paradoxically the mean values for these parameters were found to be reduced in knees with patellofemoral pain. Patella height did not substantially vary between knees with patellofemoral pain and those without. Bone scintigraphy of 7 of the knees with patellofemoral pain revealed a spectrum of activity from complete normality (3 knees) to tricompartmental increase in activity (2 knees). Increased activity localised to the patellofemoral articulation was evident in 2 knees. We conclude that despite favourable overall results, the Duracon prosthesis fails to eliminate patellofemoral pain without patella resurfacing. This conflicts with excellent reported results using this anatomic prosthesis with patella resurfacing. The presence of patellofemoral pain correlates well with a poor AKKS, but the role of plain radiography and bone scintigraphy as investigative tools remains unclear

Study Design: Retrospective Series. Objectives: To analyse loss of correction of the anterior wedge angle and the components responsible for the recurrence of kyphosis after surgical stabilisation of dorsolumbar fractures, and to assess the return of functional capacity in these patients. Materials and Methods: Between January 1998 and March 2003, 34 patients had posterior stabilisation performed with the Universal Spine System (Synthes) for dorsolumbar fracture at a single level with no neurological deficit. There were 26 AO Type A fractures, 5 Type B fractures, and 3 Type C fractures. Serial standing lateral radiographs were taken from the immediate postoperative period to the most recent follow-up. The anterior wedge angle, the heights of the discs above and below the fractured vertebra, and the heights of the vertebral bodies above, at, and below the fractured level were measured. The height at each level was measured in three segments (anterior, middle and posterior). The values were normalised to avoid discrepancies while comparing radiographs. The difference in the height of each segment measured between the immediate postoperative period and the most recent follow-up were computed. Short Form 36 (SF-36) was used to assess the functional outcome in each. Results: The mean follow-up period was 23.6 months (9 to 48 months). The mean anterior wedge angle was 10.1 ± 7.2 degrees in the immediate postoperative period and 17.1 ± 10.9 degrees at latest follow-up (p< 0.001). The mean loss of correction was 7.0 ± 8.5 degrees (−11 to 24) and this showed a linear relationship to the preoperative anterior wedge angle. Furthermore there was a linear increase in the loss of correction of the angle as the follow-up period increased. The correlation between the corresponding difference in the height of each segment and the degree of loss of correction of the anterior wedge angle showed significant correlation to the decrease in the anterior segment height at the fractured vertebral body level (Pearson’s coefficient r=0.53 significant at 0.01 level, p=0.001). The mean physical function score from SF-36 was 56.3 and the mean bodily pain score was 49.7. There was no relationship to the angle of kyphosis at follow-up to the physical function score (r=0.12, p=0.50) and the bodily pain score (r=0.14, p=0.44). Conclusions: There is a progressive loss of correction (increasing kyphosis) after posterior stabilisation with instrumentation that roughly approximates the initial decrease in anterior height of the fractured vertebral body. The degree of loss of correction does not depend on the type of fracture. The loss of correction is related to the preoperative angle of kyphosis

Introduction. Upright body posture is maintained with the alignment of the spine, pelvis, and lower extremities, and the muscle strength of the body trunk and lower extremities. Conversely, the posture is known to undergo changes with age, and muscle weakness of lower extremities and the restriction of knee extension in osteoarthritis of the knee (knee OA) have been considered to be associated with loss of natural lumbar lordosis and abnormal posture. As total knee arthroplasty (TKA) is aimed to correct malalignment of lower extremities and limited range of motion of knee, particularly in extension, we hypothesized that TKA positively affects the preoperative abnormal posture. To clarify this, the variation in the alignment of the spine, pelvis, and lower extremities before and after TKA was evaluated in this study. Patients and methods. Patients suffering from primary knee OA who were scheduled to receive primary TKA were enrolled in this study. However, patients with arthritis secondary to another etiology, i.e. rheumatoid arthritis, trauma, or previous surgical interventions to the knee, were excluded. Moreover, patients who suffered from hip and ankle OA, cranial nerve diseases, or severe spinal deformity were also excluded. The sagittal vertical axis (SVA), the horizontal distance between the posterosuperior aspect of the S1 endplate surface and a vertical plumb line drawn from the center of the C7 vertebral body, is an important index of sagittal balance of the trunk. Thus, patients were classified into two groups based on the preoperative SVA with preoperative standing lateral digital radiographs: normal (< 40mm) and abnormal (≥ 40mm) groups. The variations in the sagittal alignment of the spine, pelvis and lower extremities were evaluated preoperatively, and at 1 and 3 months postoperatively. This study was approved by an institutional review board, and informed consent for participation was obtained from the patients. Results. Forty-nine knees in 49 patients were enrolled. Three different patterns of postural changes as well as hip and knee angles following TKA were observed. After TKA, the preoperatively normal SVA patients (26.5%) showed extension of the hip and knee joints and decrease of lumbar lordosis, while the SVA remained almost within the normal range. In the preoperatively abnormal SVA group, 13 patients (26.5%) showed extension of the knee joint while the SVA remained abnormal, however, 23 of the preoperatively abnormal SVA group patients (47.0%) showed improvement of SVA into the normal range with the extension of the hip and knee joints. Discussion. As the spine, pelvis, and lower extremities together affect body alignment, once limitation of knee extension due to severe knee OA is corrected and lower extremity alignment is improved with TKA, the lumbar lordosis may increase, and SVA could decrease. Recently, the relationship between the imbalance of the sagittal plane of the body and the risk of falls was described. From this, it could be said that TKA not only helped in recovering knee function and lower extremity alignment in severe knee OA, but also helped to improve posture and to protect from falls

Aims

The aim of this study was to investigate whether anterior pelvic plane-pelvic tilt (APP-PT) is associated with distinct hip pathomorphologies. We asked: is there a difference in APP-PT between young symptomatic patients being evaluated for joint preservation surgery and an asymptomatic control group? Does APP-PT vary among distinct acetabular and femoral pathomorphologies? And does APP-PT differ in symptomatic hips based on demographic factors?

Introduction:. Proponents of quadriceps-sparing (QS) subvastus approach for total knee arthroplasty (TKA) suggest short-term advantages including better early functional results, less pain and shorter hospital stay. However, because of potentially reduced visibility and exposure, the QS approach may compromise component alignment – an important surgeon-controlled outcome affecting implant longevity. The purpose of this study was to determine if a QS approach resulted in compromised component alignment compared to a medial parapatellar arthrotomy (MPPA), when both were performed with contemporary minimally invasive surgery (MIS) principles including small incision (≤ 15 cm), MIS instrumentation, patellar subluxation without eversion, and in situ bone cuts. Methods:. This prospective, randomized, double-blinded study enrolled 128 patients with knee osteoarthritis undergoing primary TKA using the same cemented, posterior-stabilized prosthesis. After skin incision, patients were randomized to MPPA (n = 66) or QS technique (n = 62), with all surgeries performed by two fellowship-trained arthroplasty surgeons. Using the Knee Society roentgenographic evaluation system, two reviewers blinded to the surgical approach evaluated post-operative radiographs to measure coronal and sagittal plane alignment using the standing femoral and tibial angles as well as the lateral femoral flexion and tibial angles. Inter-observer agreement was ensured by a secondary review of all x-rays where the two observers differed by more than 1 degree in their measurements of a specific radiograph. Differences in mean angles were evaluated using the general linear model and differences in proportions were evaluated using binary regression. All analyses were conducted with SAS 9.3 on the Windows Ultimate 64-bit operating system. Results:. Standing and lateral radiographs were available for 63 of 66 patients in the MPPA group and 61 of 62 patients in the QS group. No significant differences were noted in either coronal or sagittal plane component alignment between the two groups and the proportion of patients whose implants were in the normally acceptable range of alignment was not significantly different between the QS and MPPA groups (Table 1). The inter-rater reliability for each of the four radiographic measures was above .90. Conclusions:. In this prospective, randomized, blinded study, a QS surgical approach did not result in radiographic alignment differences or an increase in TKA component malalignment relative to a MPPA approach, when MIS principles were adhered to in both groups. Of all measurements, the standing tibial angle showed the most outliers in terms of acceptable alignment, with coronal plane tibial component position outside the desired range in 17.5% of patients in the MPPA group and 16.4% of patients in the QS group

Objective: An anatomical study to describe the radiographic pattern of canal, foraminal and lateral recess stenosis in degenerative lumbar stenosis associated with open and closed subluxations of the lumbar spine. Introduction: Degenerative lumbar scoliosis is a three-dimensional deformity frequently associated with facet joint subluxation. It is suggested that the causative mechanism of open subluxation is vertebral rotation, whereas closed subluxation is driven by erosion of the convex facet joint. Patients with degenerative lumbar scoliosis are predominantly symptomatic on standing. However, standing MRI scans are not currently feasible to investigate this dynamic problem, therefore an accurate interpretation of the standing and lateral radiographs is essential to effectively treat this condition. We have undertaken a study to compare standing radiographs with supine MRI to determine the pattern of nerve root entrapment with open and closed facet joint dislocations in DLS. Methods: Plain radiographs and MRI scans of 35 consecutive patients with de novo degenerative lumbar scoliosis (average age 72 years) were evaluated. Radiographic measurements included the angle of the dislocation, degree of translation, position of osteophytes, vertebral rotation and the degree and location of any stenosis present on the axial MRI images. Results: Open dislocations were associated with a pre-dominant contralateral lateral recess and/or foraminal stenosis in 74% of cases. Closed dislocations were associated with ipsilateral lateral recess and/or foraminal stenosis in 82% of cases. Both open and closed dislocations had a similar degree of vertebral rotation. 67% of open subluxations occurred at L3/4. In closed subluxations the most frequent level involved was LI/2 (53% of cases). Open dislocations are located closest to the apex of the curve, with closed dislocations being more peripheral. The curve was noted to rotate towards the apex. Conclusion: Open and closed subluxations of the lumbar spine result in different, but predictable, patterns of stenosis. The findings are important in the diagnosis and planning of treatment in patients with lumbar spinal stenosis, when associated with degenerative scoliosis and lateral spondylolisthesis