The reliability of the AOSpine Thoracolumbar Spine Injury Classification System in children: an international validation study

PurposeTo evaluate the AOSpine Thoracolumbar Spine Injury Classification System and if it is reliable and reproducible when applied to the paediatric population globally.MethodsA total of 12 paediatric orthopaedic surgeons were asked to review MRI and CT imaging of 25 paediatric patients with thoracolumbar spine traumatic injuries, in order to determine the classification of the lesions observed. The evaluators classified injuries into primary categories: A, B and C. Interobserver reliability was assessed for the initial reading by Fleiss’s kappa coefficient (k_F) along with 95% confidence intervals (CI). For A and B type injuries, sub-classification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff’s alpha (α_k) along with bootstrapped 95% CIs. A second round of classification was performed one-month later. Intraobserver reproducibility was assessed for the primary classifications using Fleiss’s kappa and sub-classification reproducibility was assessed by Krippendorff’s alpha (α_k) along with 95% CIs.ResultsIn total, 25 cases were read for a total of 300 initial and 300 repeated evaluations. Adjusted interobserver reliability was almost perfect (kF = 0.74; 95% CI 0.71 to 0.78) across all observers. Sub-classification reliability was substantial (α_k= 0.67; 95% CI 0.51 to 0.81), Adjusted intraobserver reproducibility was almost perfect (kF = 0.91; 95% CI 0.83 to 0.99) for both primary classifications and for sub-classifications (α_k = 0.88; 95% CI 0.83 to 0.93).ConclusionThe inter- and intraobserver reliability for the AOSpine Thoracolumbar Spine Injury Classification System was high amongst paediatric orthopaedic surgeons. The AOSpine Thoracolumbar Spine Injury Classification System is a promising option as a uniform fracture classification in children.Level of EvidenceIII     

Reliability of three classification systems measuring active motion in brachial plexus birth palsy

BACKGROUND: Several classification systems for the categorization of function in patients with brachial plexus birth palsy have been proposed. The purpose of this investigation was to determine the intraobserver and interobserver reliability of the modified Mallet Classification, Toronto Test Score, and Hospital for Sick Children Active Movement Scale in the evaluation of these patients. METHODS: Eighty children with brachial plexus birth palsy were evaluated by two trained examiners on two different occasions. Intraobserver and interobserver reliability was determined with use of the kappa statistic. RESULTS: On the basis of the kappa statistic, intraobserver reliability was good to excellent for individual elements of the modified Mallet Classification, Toronto Test Score, and Active Movement Scale in all age-groups. Interobserver reliability for individual elements of these three systems ranged from fair to excellent. When aggregate Toronto Test and modified Mallet scores were assessed, positive intraobserver and interobserver correlations were noted (Pearson r = 0.70 to 0.98, p < 0.001). Internal consistency (test-retest reliability) as determined by the Cronbach alpha for the aggregate Toronto Test and modified Mallet scores was excellent for each age-group (alpha > 0.90, p < 0.001). CONCLUSIONS: The modified Mallet Classification, Toronto Test Score, and Active Movement Scale are reliable instruments for assessing upper-extremity function in patients with brachial plexus birth palsy. The natural history and surgical outcomes of these patients can now be conducted with use of these reliable outcomes instruments.     

Inter- and intraobserver reliability assessment of the Cobb angle: manual versus digital measurement tools

The objective of this study is to determine the intraobserver and interobserver reliability of end vertebra definition and Cobb angle measurement using printed and digital radiographs of 48 patients with scoliosis. The Cobb angle and the end vertebra were assessed by six observers in 48 patients with scoliosis using printed and digital radiographs. Definition of end vertebra and measurement of the Cobb angle was repeated three times with a 3 week interval. Intraclass correlation coefficients (ICC) were used to determine the interobserver and intraobserver reliabilities. 95% prediction limits for the errors in measurements are provided. For the Cobb angle a mean ICC of 0.97 was determined for intra- and interobserver reliability measurement of the printed radiographs. For the electronic radiographs a mean ICC value of 0.93 was determined for interobserver reliability and a mean ICC value of 0.96 for intraobserver reliability. Intraobserver ICC for definition of end vertebrae was 0.8 for both methods. Interobserver ICC was 0.83 for the manual and 0.74 in the digital method. One pitfall in angle measurement implies the Cobb method itself which measures in two dimensions. Until we develop a proper tri-dimensional measuring system an error is introduced. For the Cobb angle measurement the definition of end vertebrae introduces the main source of error. Digital radiography does not improve the measurement accuracy.     

Reliability of renal ultrasound measurements in children

The aim of the investigation reported here was to assess the intraobserver and interobserver variability of renal measurements in children. The study comprised 56 paired measurements in 28 children (median age 7.5 years, range 3.0–15.0 years) without renal or ureterovesical anomalies. Intraobserver and interobserver reproducibility was assessed by repeated measurements of the left and right renal length, width, and thickness. Intraclass correlation coefficients (ICCs) with the corresponding 95% confidence interval (CI) were calculated. Bland and Altman plots were computed to assess the agreement of the measurements. Limits of agreement ± 2 standard deviations (SD) for the mean differences in renal measurements were derived. Intraobserver ICCs ranged from 0.93 (left and right renal width and right renal thickness) to 0.99 (left renal length), and interobserver ICCs ranged from 0.64 (right renal thickness) to 0.90 (right renal length). Limits of agreement in the Bland and Altman plots ranged from −8.0 to 9.2% (intraobserver left renal width) to the widest limit from −18.0 to 19.2% (interobserver left renal length). Overall, this study demonstrated the good reproducibility and agreement of most renal dimensions in children measured by ultrasound (US). Based on these results, we conclude that US is an appropriate measure to assess renal dimensions in both clinical and epidemiological studies.     

Goniometric versus computerized angle measurement in assessing hallux valgus

BACKGROUND: Digital workstations with high-resolution monitors are replacing standard radiographs for image evaluation and interpretation. Radiographic angles in the foot have been evaluated for interobserver and intraobserver reliability with plain films, but use of digital workstations has not been validated. Because the 1-2 intermetatarsal (IM) and hallux valgus (HV) angles help determine the most appropriate bunion procedure, the reliability of these measurements is important. METHODS: The HV and 1-2 IM angles were evaluated on preoperative radiographs of 25 patients who subsequently underwent bunion procedures. A standardized technique using a film marker and goniometer on plain film was compared with use of a mouse and computerized angle measurement software at a digital workstation. Three foot and ankle surgeons conducted these measurements at various intervals. Completion of three readings of each radiograph in each format by each observer totaled 1,800 measurements. RESULTS: Computerized measurement gave better overall reliability. For the HV angle, interobserver agreement (measurements within 2 degrees) improved from 66% with plain films to 81% with the digital workstation (p < 0.001). Intraobserver agreement increased from 72% to 80%. The 1-2 IM angle was similarly reliable with both methods for inter- and intraobserver agreement. CONCLUSIONS: This study validates the use of computer-assisted angle measurement on digital radiographs for assessment of HV and 1-2 IM angles. Computerized measurement may result in more reliable readings because it eliminates the error inherent with use of a goniometer and facilitates adjustment of radiographic lines on the computer to ensure correct alignment.     

Interobserver and intraobserver reliability of two classification systems for intra-articular calcaneal fractures

BACKGROUND: For a fracture classification to be useful it must provide prognostic significance, interobserver reliability, and intraobserver reproducibility. Most studies have found reliability and reproducibility to be poor for fracture classification schemes. The purpose of this study was to evaluate the interobserver and intraobserver reliability of the Sanders and Crosby-Fitzgibbons classification systems, two commonly used methods for classifying intra-articular calcaneal fractures. METHODS: Twenty-five CT scans of intra-articular calcaneal fractures occurring at one trauma center were reviewed. The CT images were presented to eight observers (two orthopaedic surgery chief residents, two foot and ankle fellows, two fellowship-trained orthopaedic trauma surgeons, and two fellowship-trained foot and ankle surgeons) on two separate occasions 8 weeks apart. On each viewing, observers were asked to classify the fractures according to both the Sanders and Crosby-Fitzgibbons systems. Interobserver reliability and intraobserver reproducibility were assessed with computer-generated kappa statistics (SAS software; SAS Institute Inc., Cary, North Carolina). RESULTS: Total unanimity (eight of eight observers assigned the same fracture classification) was achieved only 24% (six of 25) of the time with the Sanders system and 36% (nine of 25) of the time with the Crosby-Fitzgibbons scheme. Interobserver reliability for the Sanders classification method reached a moderate (kappa = 0.48, 0.50) level of agreement, when the subclasses were included. The agreement level increased but remained in the moderate (kappa = 0.55, 0.55) range when the subclasses were excluded. Interobserver agreement reached a substantial (kappa = 0.63, 0.63) level with the Crosby-Fitzgibbons system. Intraobserver reproducibility was better for both schemes. The Sanders system with subclasses included reached moderate (kappa = 0.57) agreement, while ignoring the subclasses brought agreement into the substantial (kappa = 0.77) range. The overall intraobserver agreement was substantial (kappa = 0.74) for the Crosby-Fitzgibbons system. CONCLUSIONS: Although intraobserver kappa values reached substantial levels and the Crosby-Fitzgibbons system generally showed greater agreement, we were unable to demonstrate excellent interobserver or intraobserver reliability with either classification scheme. While a system with perfect agreement would be impossible, our results indicate that these classifications lack the reproducibility to be considered ideal.     

Observer variability in the radiographic measurement and classification of metatarsus adductus.

The classification system of Berg was evaluated using four observers and the radiographs of 42 feet from patients with metatarsus adductus. Interobserver disagreement in diagnosis was 36%. Intraobserver inconsistency averaged 26%. The error range for the lateral and anteroposterior talocalcaneal angle measurement was 13.6 and 15.1 degrees intraobserver and 19.8 and 25.2 degrees interobserver, respectively. There was no correlation between classification and the length of time required for cast correction. The irregularity of hindfoot ossification centers makes measurements inconsistent and seriously reduces the usefulness of classification based on such measurements.     

Intraobserver and interobserver agreement in anal endosonography

BACKGROUND: The aim of this study was to determine intraobserver and interobserver agreement for sonographic measurements of anal canal structures using anal endosonography (AES), and to determine interobserver agreement for the diagnosis of anal sphincter disruption. METHODS: Fifty-one consecutive patients referred for AES for the investigation of possible sphincter abnormality were examined. Studies were reviewed by two observers who measured anal canal structures at defined levels and locations, and recorded an opinion on sphincter integrity. Repeated measurements made by each observer were compared to determine intraobserver agreement, and measurements and diagnoses were compared between observers to determine interobserver agreement. RESULTS: Intraobserver agreement was better than interobserver agreement for measurements of anal canal structures. Interobserver limits of agreement for external sphincter measurements spanned 5 mm, whereas those for the internal sphincter spanned 1.5 mm. Interobserver agreement for diagnosis of sphincter disruption and internal sphincter echogenicity was very good (kappa = 0.80 and 0.74 respectively). CONCLUSION: The limits of agreement for intraobserver and interobserver measurements of anal canal structures on AES have been defined. Interobserver assessment of sphincter disruption is very good.     

Good inter- and intraobserver reliability for assessment of the slip angle in 77 hip radiographs of children with a slipped capital femoral epiphysis

Background and purpose — The decision on and the outcome of treatment for a slipped capital femoral epiphysis (SCFE) depend on the severity of the slip. In 2015, web-based registration was introduced into the Swedish Pediatric Orthopedic Quality (SPOQ) register. To determine whether the inclusion of commonly used methods in Sweden for radiographic measurement of SCFE (the calcar femorale [CF] method and the Billing method) is justified, we measured the inter- and intraobserver reliability of these 2 measurements. We also evaluated the internationally more commonly used head-shaft angle (HSA) method.

Material and methods — 4 observers with different levels of experience with radiographic measurements analyzed 77 routine preoperative hip radiographs of children with SCFE. Inter- and intraobserver reliability was evaluated.

Results — The interobserver reliability analysis for the 4 observers showed for CF an ICC of 0.99 (CI 0.97–0.99) and for Billing an ICC of 0.99 (CI 0.98–0.99). The interobserver reliability analysis for 2 observers showed for HSA an ICC of 0.98 (CI 0.97–0.99).

Intraobserver reliability (2 observers) showed a mean difference below 1° for all 3 methods and with a 95% limit of agreement not exceeding ±6.8°.

Interpretation — We found good reliability for both intra- and interobserver measurements of all 3 methods used for the assessment of the slip angle on routine preoperative lateral hip radiographs.     

Measurement error in assessment of vertebral rotation using the Perdriolle torsionmeter.

The Perdriolle torsionmeter assesses vertebral rotation on a spinal radiograph. It is frequently used to measure improvement in spinal derotation following Cotrel-Dubousset instrumentation for scoliosis. In this study, intraobserver and interobserver measurement error was examined during use of the torsionmeter. Intraobserver error was as follows: 53% of the measurements were accurate to within 5 degrees, and 21% erred greater than 10 degrees. Error from the actual value averaged 6 degrees. Interobserver error was as follows: Among six observers, only one third of the radiographs had measurements within 5 degrees of each other. Another one third erred by more than 10 degrees. Because of this significant intraobserver and interobserver error, precise measurements of rotation using the torsionmeter cannot be expected. Efforts to quantify spinal derotation with the torsionmeter after Cotrel-Dubousset instrumentation may not be valid.     

Reliability of popliteal angle measurement: a study in cerebral palsy patients and healthy controls

The popliteal angle is a widely used clinical measure for hamstring contracture in cerebral palsy (CP) patients and in healthy individuals. The reliability of popliteal angle measurement is being questioned. The aim of this study is to determine the reliability of popliteal angle measurement by means of visual and goniometric assessment. METHODS: Three different observers measured the popliteal angle in 15 CP patients and 15 healthy volunteers. In each subject, popliteal angles were visually estimated and measured with a blinded goniometer twice by all observers with approximately 1 hour between measurement sessions. RESULTS: All intraclass correlation coefficients (ICCs) were lower in the CP group compared with healthy controls. The ICC for intraobserver differences was higher than 0.75 for both groups. The ICC for interobserver reliability of visual estimates and goniometric measurements was low for both groups. Intermethod ICC was higher than 0.75 for both groups. CONCLUSIONS: Measurements in the CP group seemed to be less reliable than measurements in the control group. Intraobserver reliability is reasonable for both groups, but lower in CP patients than in controls. Interobserver reliability of both visual estimates and goniometrical measurements is poor. No significant differences in reliability have been found between visual estimation and goniometric measurement. Because of poor interobserver reliability of popliteal angle measurement, this should not be the only variable in clinical decision making in CP patients.     

Reproducibility of radiographic hip measurements in adults

IntroductionHip dysplasia may cause pain and premature hip osteoarthritis. Here, our objective was to assess the inter- and intraobserver reproducibility of radiographic hip parameter measurement in adults.MethodsWe used anteroposterior pelvic radiographs and false-profile lateral hip radiographs from 30 individuals (60 hips) enrolled in a prevalence study of hip osteoarthritis. For each hip, two independent observers recorded five parameters twice, at an interval of 1 month. The five parameters were the vertical-center-edge angle (VCE), the anterior center-edge angle (vertical-center-anterior angle, VCA), the acetabular roof angle (HTE), the neck-shaft angle (CC’D), and acetabulum depth (AD). Reproducibility was assessed using Bland-Altman plots, intraclass correlation coefficients (ICCs), and kappa coefficients for the radiographic diagnosis of hip dysplasia using widely accepted cutoffs.ResultsOf the 60 hips, 51 were assessable. Intraobserver ICC values ranged from 0.72 to 0.94 and interobserver ICC values from 0.68 to 0.84. Kappa coefficients were between 0.60 and 1.00, except for the VCA angle (κ = 0.41).ConclusionIn this study, reproducibility of the main radiographic hip parameters was good according to all evaluation methods used. However, CC’D and, to an even greater extent, the VCA angle seemed challenging to measure.     

Core biopsies of renal tumors: a study on diagnostic accuracy, interobserver, and intraobserver variability

OBJECTIVE: The diagnostic accuracy of in-bench core biopsies (CBs) from renal masses, and the interobserver and intraobserver variability in pathological subtyping of renal tumors were assessed. METHODS: We performed two CBs in 62 consecutive renal masses suspected for renal cell carcinoma (RCC), obtained after radical or partial nephrectomy and, in one case, after autopsy. Routine hematoxylin-eosin (HE)-stained sections from each CB were evaluated by five pathologists on two occasions. The surgical specimen was the reference standard. Diagnostic accuracy and the generalized kappa for intraobserver and interobserver agreement were calculated. RESULTS: Five tumors were benign and 57 malignant. Eight percent to 16% of the CBs were considered inadequate for diagnosis. In 0-8% of the cases, the pathologist could not discriminate between a benign or malignant tumor. Overall accuracy ranged from 77% to 90%. Sensitivity (79-100%) and positive predictive value (100%) were high with narrow 95% confidence interval (95%CI). Specificity (100%) was high but negative predictive value (29%-100%) varied, with wide 95% CI. Interobserver agreement was fair to almost perfect (kappa=-0.010 to 0.830) for the different subtypes. In 64-81% of the CBs, the subtype was correctly classified. Intraobserver agreement was substantial (mean kappa=0.628) for all pathologists. CONCLUSION: Diagnostic accuracy of CBs was high, with a diagnostic yield varying between 84% and 92%. Pathological subtyping of CBs was highly reproducible with the exception of the chromophobe renal cell carcinoma, which was problematic on HE-stained sections only.     

Interobserver and intraobserver reliability of the classification and diagnosis for ossification of the posterior longitudinal ligament of the cervical spine

Purpose

Ossification of the posterior longitudinal ligament (OPLL) of the cervical spine has been classified into four types by lateral plain radiographs, but the reliability of the classification and of the diagnosis of either cervical OPLL or cervical spondylotic myelopathy (CSM) was unknown. We investigated the interobserver and intraobserver reliability of the classification and diagnosis for OPLL by radiographs and computed tomography (CT) images.

Methods

A total of 16 observers classified each patient’s images into five groups; OPLL continuous, segmental, mixed, circumscribed type, or CSM. To evaluate interobserver reliability, the observers first classified only radiograph images, and next both radiographs and CT images. On another day they followed the same procedure to evaluate intraobserver reliability. We also evaluated interobserver and intraobserver reliability of the diagnosis of either cervical OPLL or CSM.

Results

Interobserver reliability of the classification with radiographs only showed moderate agreement, but interobserver reliability with both radiographs and CT images showed substantial agreement. Intraobserver of reliability the classification was also improved by additional CT images. Interobserver reliability of the diagnosis with both radiographs and CT images was almost similar to with radiographs only. Intraobserver reliability of the diagnosis was improved by additional CT images.

Conclusions

This study suggested that the reliability of the classification and diagnosis for cervical OPLL was improved by additional CT images. We propose that diagnostic criteria for OPLL include both radiographs and CT images.     

Forearm cephalic vein cross-sectional area changes at incremental congestion pressures: towards a standardized and reproducible vein mapping protocol

OBJECTIVES: Duplex ultrasonography assessment of superficial forearm veins is frequently used before a hemodialysis arteriovenous fistula (AVF) is created. There is, however, no standardized preoperative duplex ultrasonography protocol. This study assessed B-mode image analysis reproducibility and reproducibility of repeated forearm superficial venous diameter measurements on different days at different venous congestion pressures (VCPs). METHODS: Diameters were determined using B-mode ultrasonography in 10 healthy male volunteers on days 1 and 14 at incremental VCP values (10 to 80 mm Hg). Intra- and interobserver agreement was assessed for B-mode image analysis by calculating interclass correlation coefficients (ICC). Reproducibility of repeated diameter measurements (maximum and minimum diameter at days 1 and 14), cross-sectional area size increase, and shape change due to incremental VCPs were determined by calculating ICC values. RESULTS: Analysis of intraobserver agreement of B-mode image interpretation yielded ICC values of 0.97 (95% confidence interval [CI], 0.94 to 0.99) and 0.97 (95% CI, 0.96 to 0.99) for determination of maximum and minimum diameters, respectively. Interobserver agreement analysis yielded ICC values of 0.95 (95% CI, 0.92 to 0.97) and 0.96 (95% CI, 0.96 to 0.99) for determination of maximum and minimum diameters, respectively. Reproducibility of repeated diameter measurements on days 1 and 14 improved substantially at incremental VCP values, with best reproducibility at VCPs >40 mm Hg. Repeated determination of cross-sectional area size increase and shape change due to VCP increase from 10 to 80 mm Hg yielded ICC values of 0.49 (95% CI, 0.19 to 1.00) and 0.09 (95% CI, 0.00 to 0.92), respectively. Maximum and minimum diameters as well as cross-sectional area size increased significantly (P < .01) due to VCP increase during both sessions. Cross-sectional area shape changed significantly (P < .01) due to VCP increase during both sessions. CONCLUSIONS: Diameter measurements on B-mode images are largely observer independent. Superficial venous cross-sectional area shape is noncircular, and cross-sectional area size depends on VCP. Both maximum and minimum venous diameters should be determined at VCPs >40 mm Hg to attain the best reproducibility. Further studies are needed to determine whether a standardized preoperative vein mapping protocol can reduce AVF nonmaturation rates.     

Transvaginal ultrasound measurement of bladder wall thickness: a more reliable approach than transperineal and transabdominal approaches

Study Type – Diagnosis (exploratory cohort)
Level of Evidence 2b OBJECTIVES To validate transperineal, transabdominal and transvaginal ultrasound (US) techniques to measure bladder wall thickness (BWT). SUBJECTS AND METHODS Women underwent US measurement of BWT at three different anatomical sites: anterior wall, dome and trigone of the bladder by two ‘blinded’ operators using transabdominal, transperineal and transvaginal approaches at separate visits and by a single operator using transabdominal and transperineal techniques. Bland–Altman analysis was used to determine interobserver reliability for all three techniques and intraobserver reliability for transabdominal and transperineal methods. RESULTS In all, 25 women were scanned. The transperineal US had a high interobserver mean difference when measuring the anterior BWT (?0.34) and a high intraobserver mean difference when measuring the anterior (0.54) and dome BWT (0.33). Transabdominal US had a high interobserver mean difference for all measurements of BWT, and a high intraobserver mean difference when measuring the trigonal thickness (0.56). Transvaginal US had a consistent interobserver mean difference for all three measurements. The transperineal and transabominal approaches had the widest intraobserver and interobserver 95% confidence intervals of the mean difference when compared with the transvaginal approach. CONCLUSIONS Transabdominal and transperineal US for measuring BWT did not have good intraobserver and interobserver reliability for measurement of the three anatomical sites to determine mean BWT. Transvaginal US had good interobserver reliability, thus mean BWT is best measured using the transvaginal approach.     

Assessment of variations in the measurement of hip ultrasonography by the Graf method in developmental dysplasia of the hip

The purpose of this study was to assess the variations in the measurement of hip ultrasonography using the Graf method in developmental hip dysplasia. Twenty-two observers independently analyzed 20 hip ultrasonograms on two occasions. Intraobserver and interobserver agreement ratios on the exact Graf classification were 65% and 51%, respectively. Intraobserver and interobserver agreement ratios on the treatment method according to the hip type were 76% and 64%, respectively. Average intraobserver and interobserver differences were 4.0 degrees and 5.1 degrees for the alpha angle, and 5.9 degrees and 10.1 degrees for the beta angle, respectively. It was concluded that having a basic knowledge of the Graf method was the key point, and the observer's previous number of examinations had no effect on the results.     

Qualitative versus quantitative radiographic analysis of foot deformities in children with hemiplegic cerebral palsy

BACKGROUND: Qualitative assessments of standing plain radiographs are frequently used to determine treatment strategies and assess outcomes for the management of a wide range of foot and ankle conditions in children. A quantitative technique for such analyses would presumably be more precise and reliable. The goal of this study was to compare qualitative and quantitative techniques for the assessment of plain radiographs of the foot and ankle in children with hemiplegic type cerebral palsy (CP). METHODS: Standing anteroposterior and lateral radiographs of the foot and ankle of the involved side for 49 children with hemiplegic CP were analyzed qualitatively by 2 pediatric orthopaedists, based upon a 3-segment (hindfoot, midfoot, and forefoot) foot model. Quantitative assessment of the same radiographs was performed by 2 examiners, using 6 radiographic measurements developed to describe the alignment of the foot based upon the same 3-segment model. Intraobserver and interobserver reliability was determined for both the qualitative and the quantitative techniques. The qualitative and quantitative techniques were compared to determine agreement. RESULTS: The qualitative technique demonstrated poor-to-fair interobserver reliability (percent agreement range, 23%-31%; weighted kappa range, 0.291-0.568). The quantitative technique demonstrated good-to-excellent intraobserver (correlation coefficient range, 0.81-0.99) and interobserver (correlation coefficient range, 0.81-0.97) reliability. Percent agreement between the quantitative and the qualitative techniques for the assessment of foot segmental alignment for each examiner ranged from 22.2% to 100% (mean agreement for examiner 1 was 51% [correlation coefficient range, 0.04-0.48]; mean agreement for examiner 2 was 65.3% [correlation coefficient range, 0.22-0.85]). Percent agreement between the quantitative technique and both observers ranged from 11.1% to 83.3% (mean agreement was 36.7% [correlation coefficient range, 0.17-0.94]). DISCUSSION: Reliable quantitative radiographic analysis of the segmental alignment of the involved foot and ankle in children with hemiplegic CP is possible and is more precise and reliable than traditional qualitative techniques. Quantitative techniques can identify a wider range of foot segmental malalignments and should facilitate deformity analysis, preoperative planning, assessment of outcome, and comparison of results between centers.     

Reliability of active range-of-motion measurement of the rotation in the forearm: comparison of three measurement devices

AIM: The aim of this study is to prove the intra- and interobserver reliability of three different methods to measure the active range-of-motion in the forearm. METHODS: These three different methods were tested on forty volunteers. In the first method pictures were made in full supination and pronation, measurement of the two angles was performed with a dedicated software. Active range-of-motion was defined as the magnitude of forearm rotation between maximum pronation and supination. The second method used a standard goniometer. The third method of assessment used a gravity goniometer (plurimeter). We randomised both the side of the patient to be examined and the sequence of the methods. Two examiners measured subsequently the range-of-motion twice with these three devices. RESULTS: We found a significant intraobserver reproducibility with the gravity goniometer. There was no significance with the goniometer or pictures. The intraobserver reproducibility of the latter two methods was poor. The interobserver reproducibility of the gravity goniometer and pictures was significant, for the goniometer it was poor. Agreement between the pictures and gravity goniometer assessment of the range-of-motion was good. None of these two methods was significantly correlated with the goniometer assessment. CONCLUSION: For reproducibility of measurement of range-of-motion in the forearm the gravity goniometer is the best method, although the measured values were 5 % greater.     

Intraobserver and interobserver reliability of the assessment of the patellar articular cartilage in osteoarthritic patients undergoing total knee arthroplasty

This study was performed to investigate intraobserver and interobserver reliability of the intraoperative assessment of patellar cartilage status and the decision on patellar resurfacing based on the cartilage assessment in osteoarthritic patients undergoing total knee arthroplasty. Photographs of patellar cartilage were taken in 80 knees of 53 patients undergoing total knee arthroplasty. Three investigators assessed the depth and size of the cartilage lesion and made a decision on patellar resurfacing, using the photographs twice. Intraobserver and interobserver reliabilities were calculated with the kappa coefficient. Cartilage assessment had substantial intraobserver (kappa = 0.77 for depth and 0.71 for size) and moderate interobserver (kappa = 0.54 for depth and 0.45 for size) reliabilities. Decision on patellar resurfacing had almost perfect intraobserver and substantial interobserver reliabilities (kappa = 0.88 and 0.68, respectively). We found that intraoperative assessment of the patellar articular cartilage and the decision for patellar resurfacing are reliable.