King Classification Research Articles

Stepease™ diabetic socks: An answer to efficacious indoor foot pressure relief- A prospective study

BackgroundDiabetic foot ulcer is commonly seen in people with diabetes mellitus. Inadequate plantar pressure offloading has been identified as a contributing factor to development of diabetic foot ulcers. Various pressure off-loading footwear are widely available in the market but poor compliance has been reported especially for indoor usage. StepEase™ diabetic socks have been designed using Ethylene Vinyl Acetate (EVA) microspheres for better redistribution of plantar pressure. The objective of this study was to determine the efficacy of StepEase™ in redistributing the foot plantar pressure and to assess patients’ satisfaction on the usage of the socks. MethodsThis was a prospective non randomized clinical trial conducted on 31 patients with diabetes mellitus with high risk foot (King's classification stage II) over a 12 weeks period. Dynamic foot plantar pressure reading was recorded at day 0, 6 weeks and 12 weeks intervals, both barefoot and with StepEase™, using Novel Pedar-X system (Novel GmbH, Munich, Germany). Patients' satisfaction and usage practice were assessed by a questionnaire. ResultsThe mean age of subjects was 57.9 years with mean body mass index (BMI) of 26 kg/m2. The mean duration of diagnosis with diabetes mellitus was 10.2 years. The mean peak plantar pressure was found to be highest at the right forefoot and left heel region, 267.6 kPa (SD113.5 kPa) and 266.3 kPa (SD 94.6 kPa) respectively. There was a statistically significant reduction of mean peak pressure (P < 0.0001 to P = 0.024) in all masked regions except the left toe region ranging from 22.3 to 47.5% (53.2–117.4 kPa). The highest reduction was seen in the right toe region (47.5%). The reduction of peak pressure was still significant (P < 0.0001 to P = 0.034) at 6 weeks ranging from 24.7% to 46.8% (46.1–100.6 kPa) and at 12 weeks, which was 22.2–49.2% (40.6–91.9 kPa). Mean usage of the socks was 4.39 days per week (SD 1.82), with the mode of 4–6 h per day. Most of the subjects were satisfied or very satisfied with the StepEase™ socks (77.4%) while 87.1% agreed to continue using the socks. None had any new ulcer development or fall during the study period. ConclusionStepEase™ was significantly effective as an indoor foot pressure relieving footwear. It resulted in significant peak plantar pressure reduction by up to 49.2% and the effect was maintained for at least 12 weeks duration.

The Predictive Factors Associated With Comorbidities for Treatment Response in Outpatients With King Classification III Diabetes Foot Ulcers.

The aim of this study is to investigate the preexisting predictive factors associated with comorbidities for diabetic foot ulcer (DFU) in King classification III at an outpatient clinic. This prospective study included 100 patients with DFU in King classification III treated at outpatient clinics in Chiayi Chang Gung Memorial Hospital from January 2011 to December 2011. The least follow-up time was 1 year. Medical documentations were in respect of patient's baseline characteristics, associated history, presence of comorbidities, follow-up time, and condition of wounds. Patients were divided into success group (healed or healing with wound reduction), stagnate group, and failure group (amputation or infection, need in-hospital medical service) in accordance with the treatment response of wounds. χ Test, Fisher exact test, and 1-way analysis of variance were used for variables in 3-group comparison, whereas Student t test was applied in 2-group comparison. The predictive factors with P value less than 0.1 were further investigated using the model of univariate logistic regression. With 3-group stratification according to treatment response-failure (n = 8), stagnate (n = 22), and success (n = 70)-the occurrence rate of retinopathy was higher in the treatment stagnate group (42.1%) than in the treatment failure (14.3%) and success groups (12.5%; P = 0.019); the rate of previous percutaneous transluminal angioplasty (PTA) history was higher in the treatment failure group (25%) than in the treatment stagnate (4.8%) and success groups (1.5%; P = 0.020). With 2-group stratification-failure (n = 8) versus nonfailure (n = 92), and success (n = 70) versus nonsuccess (n = 30)-PTA history was strongly associated with treatment failure (odds ratio [OR], 14.33; 95% confidence interval [CI], 1.71-120.32; P = 0.014), whereas retinopathy (OR, 0.21; 95% CI, 0.07-0.65; P = 0.006) was the major negative predictor for treatment success. Previous debridement met borderline significance to predict treatment nonsuccess (OR, 0.09; 95% CI, 0.01-1.01; P = 0.051). Sex, age, associated history, dyslipidemia, hypertension, coronary artery disease, cerebrovascular accident, chronic kidney disease, and end-stage renal disease and wound condition had no statistical significance. Previous PTA and retinopathy, which indicated preexisting severe vasculopathy, are univariate predictive factors for treatment failure and nonsuccess, respectively, in patients with King classification III DFU. With the subdivision of King classification III DFU, medical history taking and fundus examination are acceptable methods for risk screening at an outpatient clinic.

Classifications in Brief: The Lenke Classification for Adolescent Idiopathic Scoliosis.

Classifications in Brief: The Lenke Classification for Adolescent Idiopathic Scoliosis.

Fifteen Years and 2530 Patients: The Evolution of Instrumentation, Surgical Strategies, and Outcomes in Adolescent Idiopathic Scoliosis in a Single Institution

Over the past decade, the surgical treatment of adolescent idiopathic scoliosis (AIS) has established new techniques to reduce curve severity and shifted to include the regular use of pedicle screws. Few studies have focused on this evolving trend in AIS correction surgery. In this study, we investigated how the operative approach, instrumentation, and surgical techniques have changed over the past 15 years and to quantify the related improvements in AIS surgical treatment. This is a retrospective review of a prospective AIS registry in a single center. Patient data were reviewed from January 2001 to December 2015. The age and surgical case distribution were recorded for each year. Trends in classification use, instrumentation types, levels of fusion, and surgical approaches were analyzed by year. The major Cobb angles and correction rates were compared between different instrumentations and surgical approaches. A total of 2530 patients with AIS (83.0% female) were included, with a mean age of 15.14 years. Most patients underwent surgery at 14 years of age (473 patients, 18.7%), followed by 15 years of age (468 patients, 18.5%). In our center, the classification of patients with AIS shifted from the King classification to the Lenke classification in 2005. The major baseline Cobb angle of the entire cohort averaged 50.99° and this mean Cobb angle decreased to 14.41° after surgery. The correction rates for the first 3 years (2001-2003) were less than 70%, whereas the correction rates for the rest of the years were all greater than 70%. In addition, significantly higher correction rates were observed in patients with Cobb angles <90° (72.93% vs. 55.61%, P < 0.001). A total of 218 anterior-only surgeries and 109 combined anteroposterior surgeries were performed; the remaining 2205 surgeries were performed with a posterior-only approach. The use of anterior-only and anteroposterior approaches trended to decrease after 2005. The correction rate of anterior-only approaches was significantly greater than posterior-only and anteroposterior approaches (77.86%, 72.51%, and 59.37%, respectively). In patients corrected with a posterior-only approach, the screw-hook hybrid construct was used in 342 patients, whereas the all-pedicle-screw construct was used in 1835 patients. The shift from hybrid to all-screw construct occurred in 2006. In patients with thoracic AIS, the correction rate was significantly higher in the all-screw group (73.26% vs. 67.76%; P < 0.001). Consistent improvement of major curve correction has been achieved by the spine community over 15 years. After stabilized coronal correction and fewer fusion levels, the next steps in this evolution are the restoration of sagittal profiles, especially the hypokyphosis seen in patients with Lenke 1, the posterior minimally invasive approach, and a fast-track return to activity.

Assessment of Coronal Radiographic Parameters of the Spine in the Treatment of Adolescent Idiopathic Scoliosis.

To determine the most important preoperative factors that affect postoperative coronal parameters of scoliotic curves. All Adolescent Idiopathic Scoliosis (AIS) patients included in the study were classified according to Lenke and King Classification. The fusion levels were selected according to the rigidity of the existing curves (correction less than 50%), tilt of T1 and shoulders, sagittal angle of the curves and with considering stable and neutral end vertebra. The radiographic coronal parameters: shoulders tilt angle, iliolumbar angle and coronal balance were measured in all patients before, after, and in the last follow-up visit. One hundred twenty patients after mean of 25 months follow-up (18-40 months) were included in the study. Before operation, abnormal coronal balance (more than 2 cm shift) was noticed in 46 patents (38%) and in the last visit, was noted in 22 patients (18%). Multivariate regression analysis revealed a significant predictive value of the preoperative coronal balance on the last visit coronal balance (P value=0.01). Preoperative coronal balance is very important to make a balanced spine after surgery. Other parameters like Lenke classification or main thoracic overcorrection did not affect postoperative coronal decompensation.

Effect of symmetric mobilization exercises applied sagittale plane on spine flexibility and angle of trunk rotation in scoliosis

Thoracic and lumber flatback has been assumed to be the triggerring factor for idiopathic scoliosis. It is belived that rotation and lateral deviation are secondary patterns of deformity in the development of idiopathic scoliosis, and it should be possible to improve scoliosis by forces in sagittal plane. It is suggested that Physio-logic® exercises stabilize the spine posture and correct scoliosis in 3-D. The aim of this study was to assess the effect of symmetric mobilization exercise which was defined in Physio-logic®exercises on spine flexibility and angle of trunk rotation. Thirty four patients (30 female, 4 male) with adolescent idiopathic scoliosis (AIS) were included in this study. King classification was used to classify of scoliosis types. “Symmetric mobilization” exercise was done 20 repetitions, 15 sessions in supin position under physiotherapist supervision. Spine flexibility was evaluated with forward and lateral bending test and angle of trunk rotation was measured with scoliometer. Evaluations were performed before and after every session. The mean age of patients was 13.5years (range; 10-17). The mean Cobb angle was 31.64° (range; 12°- 60°) and angle of trunk rotation was 9.86° (range; 3°-16°). Statistically significant improvements were observed for all assessed measurements after the treatment (p<0.05). Our results showed that spine flexibility can be improved and angle of trunk rotation can be decreased by sagittal forces. Increasing of spine flexibility and decreasing angle of trunk rotation may prevent progression of scoliosis. We suggest that symmetric mobilisation exercises should take place in the rehabilitation programme of AIS.

Computer-aided King classification of scoliosis

Surgical planning for scoliosis relies on the classification of spinal curve pattern. The widely used King classification is subject to human measurement and judgment errors. To reduce the variability of King classification, a computer-aided method is proposed and its reliability is evaluated in this study. At the first step, endplate inclination and position of each vertebra are measured by a computerized system on the posteroanterior radiograph. Based on these measurements, the apical and end vertebrae are identified and then the Cobb angles are calculated automatically. The system subsequently classifies the curve types automatically based on the computerized Cobb measurements, the vertebral inclination, and the analysis of the relationship between the center sacral vertical line, and the apical lumbar vertebra. Five observers participated in the experiments. The kappa statistic was used to evaluate the variability. Classifications of 105 scoliotic cases by the five observers showed that with the aid of our system, the average intraobserver and interobserver kappa values improved from 0.75 to 0.90 and from 0.66 to 0.86, respectively. Results indicate that the proposed computerized system can assist a surgeon with the King classification of scoliosis.

Classification of adolescent idiopathic scoliosis (AIS)

In 1983 Howard King presented his classification system for adolescent idiopathic scoliosis (AIS) based on the experience with Harrington rod instrumentation. Curves were divided into five types and guidelines and recommendations for which levels should be instrumented were given to preserve motion as much as possible. As segmental instrumentation systems began to gain favor over the Harrington rods this system failed and led to the development of a new classification system which was presented by Lawrence Lenke in 2001. In order to define a curve type by the Lenke classification, one must identify the curve type, the lumbar modifier and, for the first time in any classification system for scoliosis, the sagittal profile was also included. The Lenke classification showed higher inter and intra-reliability compared to the King classification. It also provided a better and more reliable tool to assist surgeons in choosing the best method of treatment for each curve pattern. Although the Lenke classification is more comprehensive and reliable than the King classification it is still far from perfect. It does not address the rotational component of the deformity. New technologies which provide three-dimensional (3D) reconstruction of the spine may serve as a basis for a truly 3D classification of scoliosis and for new therapeutic concepts.

Lenke and King classification systems for adolescent idiopathic scoliosis: interobserver agreement and postoperative results

PurposeThe aim of this study was to investigate the interobserver agreement of the Lenke and King classifications for adolescent idiopathic scoliosis, and to compare the results of surgery performed based on classification of the scoliosis according to each of these classification systems.MethodsThe study was conducted in Shohada Hospital in Tabriz, Iran, between 2009 and 2010. First, a reliability assessment was undertaken to assess interobserver agreement of the Lenke and King classifications for adolescent idiopathic scoliosis. Second, postoperative efficacy and safety of surgery performed based on the Lenke and King classifications were compared. Kappa coefficients of agreement were calculated to assess the agreement. Outcomes were compared using bivariate tests and repeated measures analysis of variance.ResultsA low to moderate interobserver agreement was observed for the King classification; the Lenke classification yielded mostly high agreement coefficients. The outcome of surgery was not found to be substantially different between the two systems.ConclusionBased on the results, the Lenke classification method seems advantageous. This takes into consideration the Lenke classification’s priority in providing details of curvatures in different anatomical surfaces to explain precise intensity of scoliosis, that it has higher interobserver agreement scores, and also that it leads to noninferior postoperative results compared with the King classification method.

A Decision Tree Can Increase Accuracy When Assessing Curve Types According to Lenke Classification of Adolescent Idiopathic Scoliosis

The assignment of adolescent idiopathic scoliosis (AIS) curves into curve types (1-6), as described by Lenke et al, was evaluated by 12 independent observers using the original description versus a decisional tree algorithm. To determine whether a decision tree algorithm can improve classification accuracy using the Lenke classification for AIS. Curve type classification in AIS relies on several parameters to consider, and its relative complexity has lead to conflicting studies that reported fair-to-excellent interobserver reliability. King's classification reliability was shown to be improved using a rule-based automated algorithm. No similar algorithm for Lenke's classification currently exists. A clinical diagram derived from a decision tree was developed to help clinicians classify AIS curves. Twelve clinicians and research assistants were asked to classify AIS curves using 2 methods: the original Lenke chart alone and the decision tree diagram in addition to the Lenke Chart. Wilcoxon ranking tests were used to evaluate any difference in classification accuracy and speed for both methods. Mann-Whitney tests were used to compare experts' and nonexperts' results. Pearson correlation was calculated to evaluate the relationship between accuracy and time taken to classify. RESULTS.: Use of the decision tree for curve type determination improved classification accuracy from 77.2% to 92.9% (P = 0.005) without requiring more time to classify. This improvement was statistically significant (P < 0.05). A statistically significant correlation between accuracy and time spent classifying when the decision tree is used was also observed (R = 0.62, P = 0.032). Transfer of a computer algorithm, a decision tree, to a clinical diagram improved both accuracy ofAIS classification. Algorithmic diagrams could prove beneficial to increase classification reliability due to their systematic approach.

Selective thoracic surgery in the Lenke type 1A: King III and King IV type curves

Pedicle screw fixation enables enhanced three-dimensional correction of spinal deformities and effectively shortens the distal fusion level. However, the choice of distal fusion level is still controversial in single thoracic idiopathic scoliosis with the lumbar compensatory curve not crossing the middle line (Lenke type 1 with modifier A or King type III and IV curves).The authors retrospectively analyzed 31 patients treated by segmental pedicular instrumentation alone, affected by a single thoracic adolescent idiopathic scoliosis with a compensatory lumbar curve not crossing the midline (Lenke 1A), with an average age of 16.3 years (range 10-22 years). The patients with regard to the King classification were also assessed. A statistical analysis was performed to determine whether the two groups (King III, King IV) presented differences concerning the level of the stable vertebra (SV), end vertebra (EV), and neutral vertebra (NV) and were also analyzed the results at follow-up regarding the relationships between the SV, EV, and lowest instrumented vertebra (LIV). The statistical analysis showed a significant difference between the two curve types. In the King III type curve the SV, EV, and NV appeared to be more proximal than those of the King IV type curve and the segments between the SV, EV, and NV appeared to be reduced in King III curves compared with King IV curves. At a follow-up of 3.2 years (range 2.2-5) the thoracic curve showed a correction of 58.4% (from 62.3 degrees to 26.6 degrees ) and compensatory lumbar curve an average spontaneous correction of 52.4% (from 38.1 degrees to 18.1 degrees ).The position of the LIV was shorter than the position of the SV in 30 patients (97%) with an average "salvage" of 2.1 (from 1 to 4) distal fusion levels. Four cases (13%), all affected by a King IV type curve, presented at follow-up an unsatisfactory results due to an "adding on" phenomenon. The statistical analysis confirmed that this phenomenon was correlated with The King IV curve (P = 0.043; Chi-square test) and that the only predictive parameter for its onset was the LIV-SV difference (odds ratio = 0.093; with a confidence interval of 0.008-1): every time that in King IV curve type the LIV was three or more levels shorter than the stable vertebra at follow-up the "adding on" phenomenon was present. The authors conclude that Lenke's type 1 with modifier A includes two kinds of curves, King III and King IV and that the Lenke's type 2 curves and King V with the lumbar curve not crossing the middle line have a similar behavior. Therefore, it is of authors' opinion that "the adding on phenomenon" could be prevented by more rigidly defining K. IV versus K. III curves. In Lenke's 1/2 A-K. IV/V type with the rotation of the first vertebra just below the thoracic lower EV in the same direction as the thoracic curve, and when SV and EV show more than two levels of difference, it is necessary to extend the lower fusion down to L2 or L3 (not more than two levels shorter than the SV). Whereas in Lenke's 1/2 A-K. III/V with the rotation of the first proximal vertebra of lumbar curve in the opposite direction to the thoracic apex and when SV and EV show not more than two level gap differences, the position of the lowest instrumented vertebra can be two or three levels shorter than the stable vertebra with satisfactory postoperative spinal balance. Therefore, the stable vertebra and the rotation of lumbar curve are considered to be a reliable guide for selecting the lower level of fusion.

Intraobserver and interobserver reliability of the King, Lenke, and PUMC classification systems for idiopathic scoliosis

To evaluate the intraobserver and interobserver reliability and main influencing factors of the King, Lenke, and PUMC classification systems for idiopathic scoliosis (IS) using radiographs that had not been premeasured. Fifty-six patients with IS, 9 male and 47 female, aged 15.4 (11 - 18), underwent preoperative X-ray photography of spine standing full-length posteroanterior and lateral films and left and right supine side-bending radiographs. The films were read by four orthopedic surgeons independently to do measurement and typing according to the King, Lenke, and PUMC classification systems respectively. Two weeks later, the sequence of the X-ray films was re-ordered and the 4 surgeons read them and did measurement and typing once more. The average percentage of intraobserver and interobserver agreement was calculated. Kappa coefficients were used to determine the intraobserver and interobserver reliability. King classification demonstrated fair interobserver reliability and excellent intraobserver reliability. The mean interobserver reliability was 65.8% (Kappa coefficient = 0.542), while the intraobserver reliability was 82.6% (Kappa coefficient = 0.767). The main reason of disagreement was distinguishment of the King type II and type III. Another reason was assessment of King type V. The complete Lenke classification demonstrated poor reliability. The mean interobserver reliability was 50.0% (Kappa coefficient = 0.438), and the intraobserver reliability was 47.0% (Kappa coefficient = 0.402). The 3 components of Lenke classification had fair interobserver and intraobserver reliability when they were examined separately. The main reasons for disagreement arose from judging whether there was a structural upper thoracic curve and assigning sagittal thoracic modifier. The PUMC type demonstrated excellent intraobserver and interobserver reliability with a mean interobserver reliability of 87.8% (Kappa coefficient = 0.757), and a mean intraobserver reliability of 92.9% (Kappa coefficient = 0.958). Its subtypes demonstrated fair agreement with the mean interobserver reliability of 70.2% (Kappa coefficient = 0.629), and a mean intraobserver reliability of 74.1% (Kappa coefficient = 0.674). The main reasons for disagreement were definition of a curvature and Cobb angle measurement. King and PUMC classification systems have higher interobserver and intraobserver reliability than Lenke classification. The reliability levels of the 3 classification systems are all influenced by many factors. Judgment of an upper thoracic curve, variable of Cobb angle measurement, and relationship of the central vertical sagittal line to apex of curve are the common reasons for disagreement in these 3 classifications.

Selective fusion in adolescent idiopathic scoliosis

Selective fusion in adolescent idiopathic scoliosis

Identification of Spinal Deformity Classification With Total Curvature Analysis and Artificial Neural Network

In this paper, a multilayer feed-forward, back-propagation (MLFF/BP) artificial neural network (ANN) was implemented to identify the classification patterns of the scoliosis spinal deformity. At the first step, the simplified 3-D spine model was constructed based on the coronal and sagittal X-ray images. The features of the central axis curve of the spinal deformity patterns in 3-D space were extracted by the total curvature analysis. The discrete form of the total curvature, including the curvature and the torsion of the central axis of the simplified 3-D spine model was derived from the difference quotients. The total curvature values of 17 vertebrae from the first thoracic to the fifth lumbar spine formed a Euclidean space of 17 dimensions. The King classification model was tested on this MLFF/BP ANN identification system. The 17 total curvature values were presented to the input layer of MLFF/BP ANN. In the output layer there were five neurons representing five King classification types. A total of 37 spinal deformity patterns from scoliosis patients were selected. These 37 patterns were divided into two groups. The training group had 25 patterns and testing group had 12 patterns. The 25-pattern training group was further divided into five subsets. Based on the definition of King classification system, each subset contained all five King types. The network training was conducted on these five subsets by the hold-out method, one of cross-validation variants, and the early stop method. In each one of the five cross-validation sessions, four subsets were alternatively used for estimation learning and one subset left was used for validation learning. Final network testing was conducted with remaining 12 patterns in testing group after the MLFF/BP ANN was trained by all five subsets in training group. The performance of the neural network was evaluated by comparing between two network topologies, one with one hidden layer and another with two hidden layers. The results are shown in three tables. The first table shows network errors in estimation learning and the second table shows identification rates in validation learning. The network errors and identification rates in the last round of network training and testing are shown in the third table. Each table has a comparison for both one hidden layer and two hidden layer networks.

A Comparison of the Lenke and King Classification Systems in the Surgical Treatment of Idiopathic Thoracic Scoliosis

Retrospective case control study. To evaluate the use of the Lenke and King classification systems in the surgical treatment of main thoracic adolescent idiopathic scoliosis (AIS), with a specific focus on radiographic and patient reported outcomes. There is considerable debate as to whether King or Lenke classification best fulfills the criteria for a useful classification to determine distal fusion level, i.e., is mentally descriptive of the curve being treated, uses reproducible information to provide guidance in determining distal fusion level, is prognostic of patient reported and radiographic outcomes, and has good user reproducibility. Patients operated for AIS between 1986 and 2002 with posterior spinal fusion and dual rod posterior instrumentation were retrospectively classified according to the Lenke and King classification systems. Only patients with Lenke type I curves and minimum 2-year follow-up were included. Preoperative and most recent postoperative radiographs were reviewed. The Lenke and King recommended distal fusion levels were calculated for each patient according to criteria obtained from the literature, and were compared to our actual fusion level. Patients were divided into groups based on our actual distal fusion level (i.e., longer, shorter, or in agreement with Lenke and King). The radiographic parameters and SRS 24 outcomes of patients within each group were compared. Seventy-five patients with Lenke type 1 AIS were included in the study. The distribution of King curve types were: 31 King II curves, 34 King III curves, 9 King IV curves, and 1 double major curve. Our actual distal fusion level was in agreement with the calculated Lenke recommendation in 49% and the King recommendation in 51% of the cases. Difficulties in using the Lenke classification system were identified in up to 59% of the study patients. There were no statistically significant objectives or patient reported (SRS) differences between the groups fused in agreement, longer, or shorter than the calculated Lenke or King recommendations. At intermediate follow-up, there does not seem to be significant radiographic or patient reported differences whether fusion levels are in agreement, longer, or shorter than those recommended by the Lenke or King classification systems.

Inter-trial and test–retest reliability of kinematic and kinetic gait parameters among subjects with adolescent idiopathic scoliosis

Gait analysis is actually used in subjects with scoliosis to determine the change in lower limb parameters after surgery, but the reliability of these parameters still remained unknown. The purpose of this study was to assess the repeatability of traditional gait parameters in subjects with adolescent idiopathic scoliosis (AIS) and to estimate the associated standard error of measurement (SEM). A test-retest design was used to assess the reliability of gait parameters at self-selected and fast speeds. A convenience sample of 20 girls aged from 12 to 17 years, with an idiopathic scoliosis (King classification: types I, II or III; Cobb angle 17-50 degrees) participated in the study. Five good trials were recorded on two occasions. The time-distance, kinematic, and kinetic gait parameters were recorded using foot-switches in combination with a three-dimensional motion analysis system (Optotrak) and Advanced Mechanical Technologies Inc., (AMTI) Watertown, MA, USA; force plates. The coefficients of dependability and SEM derived from the generalizability theory were used to assess the reliability. Inter-trial reliability was good for time-distance, kinematic, and kinetic (absolute and normalized) gait parameters except for the medio-lateral ground reaction force (GRF) component and the ankle dorsiflexor moment (phi = 0.60-0.77). Test-retest reliability was higher for the kinetic than for the kinematic parameters. These coefficients ranged from 0.42 to 0.58 for the time-distance parameters; from 0.55 to 0.88 for the angular displacements and from 0.25 to 0.99 for the kinetic parameters. The SEMs were lower than 3.3 degrees for the angular displacements and lower than 8 Nm (0.15 Nm/kg) and 36 W (0.54 W/Kg) for the joint moments and powers regardless of the speed. Several gait parameters are reliable among subjects with AIS and can be used to assess the evolution of the spinal modifications and the impact of treatment on their lower limb gait pattern.

Computer-Assisted Algorithms Improve Reliability of King Classification and Cobb Angle Measurement of Scoliosis

Interobserver and intraobserver reliability study of improved method to evaluate radiographs of patients with scoliosis. To determine the reliability of a computer-assisted measurement protocol for evaluating Cobb angle and King et al classification. Evaluation of scoliosis radiographs is inherently unreliable because of technical and human judgmental errors. Objective, computer-assisted evaluation tools may improve reliability. Posteroanterior preoperative radiographic images of 27 patients with adolescent idiopathic scoliosis were each displayed on a computer screen. They were marked 3 times in random sequence by each of 5 evaluators (observers) who marked 70 standardized points on the vertebrae and sacrum in each radiograph. A computer program (Spine 2002;27:2801-5) that identified curves, calculated Cobb angles, and generated the King et al classification automatically analyzed coordinates of these points. The interobserver and intraobserver variability of the Cobb angle and King et al classification evaluations were quantified and compared with values obtained by unassisted observers. Average Cobb angle intraobserver standard deviation was 2.0 degrees for both the thoracic and lumbar curves (range 0.1 to 8.3 degrees for different curves). Interobserver reliability was 2.5 degrees for thoracic curves and 2.6 degrees for lumbar curves. Among the 5 observers, there was an inverse relationship between repeatability and time spent marking images, and no correlation with image quality or curve magnitude. Kappa values for the variability of the King et al classification averaged 0.85 (intraobserver). Variability of Cobb measurements compares favorably with previously published series. The classification was more reliable than achieved by unassisted observers evaluating the same radiographs. The same principles may be applicable to other radiographic measurement and evaluation procedures.

Does Gender Affect Outcome of Surgery in Adolescent Idiopathic Scoliosis?

A retrospective follow-up study comparing 2 matched groups. To compare long-term results of operative treatment of adolescent idiopathic scoliosis (AIS) between males and females matched for age, curve magnitude and type, and the instrumentation used. It has been suggested that in AIS, the spine is more rigid in males than in females, because brace treatment fails to halt progression of the curves in males. However, there are no studies comparing the results of surgical treatment of AIS between males and females. Thirty male and female pairs were matched for age (+/-1 year), major curve magnitude (+/-5 degrees), curve type according to the King classification, and the instrumentation used (Harrington in 11 pairs, Cotrel-Dubousset in 9 pairs, and Universal Spine System in 10 pairs). The mean age at the time of operation was 16.2 +/- 2.6 years for the males and 15.5 +/- 2.3 years for the females. The mean follow-up times were 14.3 years (range 6.7-23.0 years) and 14.1 year (range 6.4-23.7 years), respectively. Radiographs were obtained presurgery and after surgery, at the 2-year follow-up assessment, and at the final follow-up visit. In addition, a physical examination was performed, and the Scoliosis Research Society (SRS) questionnaire was completed. Spine mobility and nondynamometric trunk strength were measured at the final follow-up visit. Before surgery, the mean Cobb angle of the thoracic curve was 55 degrees (range 42-83 degrees) in the males and 56 degrees (range 43-80 degrees) in the females. In bending radiographs, the major curve reduced significantly more in females than in males (P = 0.027). The mean angles of the thoracic and lumbar curves were similar at all follow-up visits. The final correction of the thoracic curves was 30% (range -19-65%) in the males and 33% (range -7-71%) in the females (not significant). No significant difference was observed in thoracic kyphosis or lumbar lordosis between the study groups at the final follow-up. The total SRS questionnaire score averaged 96 (range 66-113) in the males and 95 (range 75-108) in the females. None of the males and 2 of the females reported back pain often or very often in the questionnaire. Nondynamometric trunk strength measurements corresponded with reference values, on average, and were similar in both groups. Abnormal trunk side bending tended to be more common in the males than in the females (43% vs. 23%, P = 0.10, not significant). Curves in males appear to be more rigid than in females with AIS. However, posterior surgery for AIS provides similar short and long-term results in males and females.

Factors determining the final outcome of treatment of idiopathic scoliosis with the Boston brace: a longitudinal study.

This study tries to determine factors influencing the final outcome of treatment of idiopathic scoliosis with the Boston brace and to compare the results with the natural history. One hundred and fifty-one patients, 130 girls and 21 boys, treated between 1982 and 1991, were reviewed. A series of continuous and categorical variables were measured, allowing for the construction of a multiple regression equation. Continuous variables were age at discovery of the curve, time of interval between discovery and treatment and age at the beginning of treatment. Furthermore age of menarche, duration of treatment, duration of weaning and age and time of follow-up were noted. Continuous numerical variables were the Cobb angle, the apical vertebral rotation, and the Risser stage. Categorical variables consisted of the results of a questionnaire and the King's classification of the curve. Good results are achieved in older children, with low Cobb angles and advanced maturity, who are, however, the very ones not expected to progress, as also indicated in studies on natural history. Brace treatment seems not to alter the natural history in general, and especially not in the older child; this is the case from age 12 years and Risser stage 2 onwards. In the younger child, a brace is probably still indicated, because it has been proved that a scoliosis is more prone to progress and that a possible positive result can still not be ruled out, as long as randomized control trials are not conducted.

Factors determining the final outcome of treatment of idiopathic scoliosis with the Boston brace: a longitudinal study

This study tries to determine factors influencing the final outcome of treatment of idiopathic scoliosis with the Boston brace and to compare the results with the natural history. One hundred and fifty-one patients, 130 girls and 21 boys, treated between 1982 and 1991, were reviewed. A series of continuous and categorical variables were measured, allowing for the construction of a multiple regression equation. Continuous variables were age at discovery of the curve, time of interval between discovery and treatment and age at the beginning of treatment. Furthermore age of menarche, duration of treatment, duration of weaning and age and time of follow-up were noted. Continuous numerical variables were the Cobb angle, the apical vertebral rotation, and the Risser stage. Categorical variables consisted of the results of a questionnaire and the King's classification of the curve. Good results are achieved in older children, with low Cobb angles and advanced maturity, who are, however, the very ones not expected to progress, as also indicated in studies on natural history. Brace treatment seems not to alter the natural history in general, and especially not in the older child; this is the case from age 12 years and Risser stage 2 onwards. In the younger child, a brace is probably still indicated, because it has been proved that a scoliosis is more prone to progress and that a possible positive result can still not be ruled out, as long as randomized control trials are not conducted.