Concordancia interobservador en la clasificación de Paprosky en un hospital de un país de una economía emergente / Inter-observer agreement in the Paprosky classification in a hospital in a country of an emerging economy

Resumen: Introducción: La evaluación y manejo de la pérdida ósea acetabular en la artroplastía total de cadera es un desafío para los cirujanos ortopédicos, deseamos en este estudio determinar la concordancia interobservador en la clasificación de Paprosky para defectos acetabulares. Material y métodos: Estudio observacional, descriptivo, longitudinal, prospectivo. Se realizó utilizando las radiografías anteroposteriores de cadera de pacientes programados para artroplastía total de cadera primaria o de revisión con defecto óseo acetabular, sistema de rayos X local Sinapse, se valoraron 20 radiografías por observador tomadas de manera aleatoria (médicos adscritos al servicio de reemplazos articulares con experiencia mínima de cinco años) utilizando la clasificación de Paprosky de manera espontánea (sin clases previas) de defectos acetabulares, se evaluó la concordancia interobservador mediante el coeficiente de kappa de Cohen. Resultados: Se obtuvo una concordancia interobservador en promedio para la clasificación de Paprosky de defectos acetabulares utilizando el coeficiente de kappa de Cohen, el análisis de concordancia se hizo empleando el programa estadístico Statistical Package for the Social Sciences de 0.237. Conclusiones: Tanto la hipótesis nula (kappa mayor de 0.80 valor considerado óptimo) como la hipótesis alternativa (kappa de 0.41 a 0.80 valor igual a moderada a buena) no concordaron con nuestro estudio (kappa igual a 0.237) valor igual a leve, además se demostró que a mayor defecto acetabular menor es la concordancia interobservador en cirujanos en nuestra institución.

Abstract: Introduction: The evaluation and management of acetabular bone loss in total hip arthroplasty is a challenge for orthopedic surgeons, we wish in this study to determine the inter-observer concordance in the Paprosky classification for acetabular defects. Material and methods: Observational, descriptive, longitudinal, prospective study. It was performed using anteroposterior hip radiographs of patients scheduled for primary total hip arthroplasty or revision with acetabular bone defect, Sinapse local X-ray system, 20 X-rays were assessed per observer taken randomly (doctors assigned to the joint replacement service with minimum experience of five years) using the Paprosky classification spontaneously, (without previous classes) for acetabular defects, inter-observer concordance was assessed using Cohen's Kappa coefficient. Results: An interobserver agreement was obtained on average for the Paprosky classification of acetabular defects using the Cohen's Kappa coefficient, the concordance analysis was done using the statistical program statistical package for the social sciences of 0.237. Conclusions: Both the null hypothesis (Kappa greater than 0.80 value considered optimal) and the alternative hypothesis (Kappa from 0.41 to 0.80 value equal to moderate to good) did not agree with our study (Kappa equal to 0.237) value equal to mild, in addition , it was shown that the greater the acetabular defect, the lower the interobserver agreement in surgeons in our institution.

Utility of Radiographs, Computed Tomography, and Three Dimensional Computed Tomography Pelvis Reconstruction for Identification of Acetabular Defects in Residency Training / 대한고관절학회지

PURPOSE: The Paprosky classification system of acetabular defects is complex and its reliability has been questioned. The purpose of this study was to evaluate the effectiveness of different radiologic imaging modalities in classifying acetabular defects in revision total hip arthroplasty (THA) and their value of at different levels of training. MATERIALS AND METHODS: Bone defects in 8 revision THAs were classified by 2 fellowship-trained adult reconstruction surgeons. A timed presentation with representative images for each case (X-ray, two-dimensional computed tomography [CT] and three-dimensional [3D] reconstructions) was shown to 35 residents from the first postgraduate year of training year of training (PGY-1 to PGY-5), 2 adult reconstruction fellows and 2 attending orthopaedic surgeons. The Paprosky classification of bone defects was recorded. The influence of image modality and level of training on classification were analyzed using chi-square analysis (alpha=0.05). RESULTS: Overall correct classification was 30%. The level of training had no influence on correct classification (P=0.531). Using X-ray led to 37% correctly identified defects, CT scans to 33% and 3D reconstructions to 20% of correct answers (P < 0.001). There was no difference in correct classification based defect type (P < 0.001). Regardless of level of training or imaging, 64% of observers recognized type 1 defects, compared to only 16% correct recognition of type 3B defects. CONCLUSION: Using plain X-rays led to an increased number of correct classification, while regular CT scan and 3D CT reconstructions did not improve accuracy. The classification system of acetabular defects can be used for treatment decisions; however, advanced imaging may not improve its utilization.

Acetabular Rebision Using Acetabular Reinforcement Ring and Allograft Impaction

Purpose: We wanted to evaluate the clinical and radiologic results of acetabular revision using the acetabular reinforcement ring and also the allograft impaction in the acetabulum having deficient bone stock. Material and Methods: Nineteen hips revision arthroplasty were performed in 18 patients (9 males and 9 females) with using an acetabular reinforcement ring and allograft between July 1993 and December 2003. The patients were followed for an average of 64 months (range: 24-153). The mean age at the time of arthroplasty was 59 years old (range: 34-76). The causes of revision were aseptic loosening of the acetabular component in 16 cases, severe progressive osteolysis around the acetabular component in 2 cases and Girdlestone state after infected total hip arthroplasty in one case. The acetabular deficiency was type II in 5 hips, type III in 13 hips, and type IV in one hip according to the AAOS classification. The clinical results were evaluated using the modified Harris hip score, and the radiologic results were evaluated by assessing the preoperative and serial follow-up radiographs. Results: The mean preoperative Harris hip score of 47 was improved to 86 points at the latest follow-up. Periacetabular osteolysis was found in 2 cases, which did not progress at follow-up. The anatomic hip center was restored after revision arthroplasty (p<0.05). Complications were dislocation in 2 cases, breakage of the hook of the Ganz ring in one case, heterotopic ossification in one case and femoral artery injury in one case. All cases showed stable fixation of the acetabular component and good remodelling of the impacted allograft. There was neither recurrence of dislocation nor progression of the acetabular component loosening on the radiographs. Conclusion: Acetabular revision with acetabular reinforcement ring and allograft impaction showed satisfactory clinical and radiologic results with restoration of the hip center and consolidation of the allograft.

Acetabular Defect in Cerebral Palsied Hip Instability: Quantitative Analysis of 3D CT / 대한정형외과학회잡지

PURPOSE: To analyze the acetabular wall defects of cerebral palsied hips using 3 dimensional computed tomography (3D CT). MATERIALS AND METHODS: 56 hips of 28 cerebral palsy patients with hip instability were included and contralateral hips of unilateral LCP patients were used as a control. We categorized the instabilities into dislocation and subluxation, and described the location of acetabular defects qualitatively. Anterosuperior, lateral, and posterosuperior acetabular indices were measured on the quantitative base by multi-planar reformation, and acetabular volume was calculated. RESULTS: In qualitative study, posterior defect was the most predominant in subluxation group, whereas global defect was predominant in dislocation group. All three indices in both subluxation and dislocation group increased when compared with those of control (p<0.05). On the other hand, lateral index increased in dislocation group when compared with subluxation (p<0.05). The acetabular volume was largest in control group, while the volume of dislocation group was least, and that of subluxation was between the two (p<0.05). CONCLUSION: Subluxated hips mainly represent posterior acetabular wall defects. As dislocation progresses, global wall defect was noticeable and acetabular volume decreased. Gross visual wall defects was not always consistent with true wall defect. So, quantitative measurement should be considered when determining the acetablular defects.

Progress in research on classification and reconstruction of acetabular defects in revision of total hip arthroplasty / 中华创伤骨科杂志

Management of acetabular deficiency in revision of hip arthroplasty can be extremely challenging. A successful outcome requires careful preoperative planning, identification of complex defects, and stable reconstruction. Now, acetabular reconstructions that are conducted with autograft and allograft filling the defect and special techniques are effective. As more revisions of total hip arthroplasty take place in clinic, a systematic approach to diagnosis and treatment becomes more important. This paper reviews the progress made in classification and reconstruction of acetabular defects.

Revision Arthroplasty in Acetabular Defect / 대한정형외과학회잡지

It has been established that total hip replacement arthoplasty is one of the most excellent treatment modalities of adult hip joint disease. But aseptic loosening of the acetabular component is a main cause of revision and acetabular defects must be supported to engage the acetabular cup. Many authors have been managed this problem with the various methods of using acetabular ring, bone cement, autogenous or allogeoous bone graft and bipolar endoprosthesis. As the time goes on, it is inevitable that the numbers of revision arthroplasty cases will increase. We observed 36 patients, 39 cases of revision arthroplasty from 1981 and analysed the cases. 27 cases were treated by autogenous lilac block bone to support the acetabular defects. Complete or incomplete iliac block bone was grafted to superior, medial and posterior aspect of acetabulum. Some screws were inserted when they are needed for bone graft fixation. Hip spica casts were applied in 24 cases for 2 or 3 months and crutches were used for about 3 months. Pre-and postoperative hip joint functions by Harris score was increased form average 58.2 to 81.3(23.1 points increment). Sixteen cases were followed up for more than one year and all the bone grafts were united well without bone resorption. We found that autogenous iliac block bone can support the acetabular defects satisfactorily in revision arthroplasty cases.