Bootstrap imputation minimized misclassification bias when measuring Colles' fracture prevalence and its associations using health administrative data.

OBJECTIVES: Misclassification bias can result from the incorrect assignment of disease status using inaccurate diagnostic codes in health administrative data. This study quantified misclassification bias in the study of Colles' fracture. STUDY DESIGN AND SETTING: Colles' fracture status was determined in all patients >50 years old seen in the emergency room at a single teaching hospital between 2006 and 2014 by manually reviewing all forearm radiographs. This data set was linked to population-based data capturing all emergency room visits. Reference disease prevalence and its association with covariates were measured. A multivariate model using covariates derived from administrative data was used to impute Colles' fracture status and measure its prevalence and associations using bootstrapping methods. These values were compared with reference values to measure misclassification bias. This was repeated using diagnostic codes to determine Colles' fracture status. RESULTS: Five hundred eighteen thousand, seven hundred forty-four emergency visits were included with 3,538 (0.7%) having a Colles' fracture. Determining disease status using the diagnostic code (sensitivity 69.4%, positive predictive value 79.9%) resulted in significant underestimate of Colles' fracture prevalence (relative difference -13.3%) and biased associations with covariates. The Colles' fracture model accurately determined disease probability (c-statistic 98.9 [95% confidence interval {CI} 98.7-99.1], calibration slope 1.009 [95% CI 1.004-1.013], Nagelkerke's R2 0.71 [95% CI 0.70-0.72]). Using disease probability estimates from this model, bootstrap imputation (BI) resulted in minimal misclassification bias (relative difference in disease prevalence -0.01%). The statistical significance of the association between Colles' fracture and age was accurate in 32.4% and 70.4% of samples when using the code or BI, respectively. CONCLUSION: Misclassification bias in estimating disease prevalence and its associations can be minimized with BI using accurate disease probability estimates.

Reliability and reproducibility of classifications for distal radius fractures.

OBJECTIVE: The aim of this study was to evaluate the interobserver reliability and intraobserver reproducibility of the Universal, AO, Fernandez and Frykman classifications for distal radius fractures. METHODS: Fifty standard sets of posteroanterior and lateral roentgenograms of displaced distal radius fractures were classified two times by two groups of evaluators at 2-month intervals. The first group consisted of 10 orthopedic surgeons with a minimum of 5 years of experience. The second group consisted of 10 orthopedic residents in their first two years of practice. Interobserver reliability and intraobserver reproducibility were assessed using Cohen's kappa test. RESULTS: None of the classifications achieved good- very good reliability levels. The Fernandez classification had a moderate and the others had a fair interobserver agreement kappa coefficient. All classifications had fair kappa intraobserver agreement although the Frykman and Fernandez classifications had better results. CONCLUSION: None of the classification systems were superior in terms of reliability and reproducibility. The reliability and reproducibility rates of all four classifications were insufficient.

Are distal radius fracture classifications reproducible? Intra and interobserver agreement.

CONTEXT AND OBJECTIVE: Various classification systems have been proposed for fractures of the distal radius, but the reliability of these classifications is seldom addressed. For a fracture classification to be useful, it must provide prognostic significance, interobserver reliability and intraobserver reproducibility. The aim here was to evaluate the intraobserver and interobserver agreement of distal radius fracture classifications. DESIGN AND SETTING: This was a validation study on interobserver and intraobserver reliability. It was developed in the Department of Orthopedics and Traumatology, Universidade Federal de São Paulo - Escola Paulista de Medicina. METHOD: X-rays from 98 cases of displaced distal radius fracture were evaluated by five observers: one third-year orthopedic resident (R3), one sixth-year undergraduate medical student (UG6), one radiologist physician (XRP), one orthopedic trauma specialist (OT) and one orthopedic hand surgery specialist (OHS). The radiographs were classified on three different occasions (times T1, T2 and T3) using the Universal (Cooney), Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF), Frykman and Fernández classifications. The kappa coefficient (kappa) was applied to assess the degree of agreement. RESULTS: Among the three occasions, the highest mean intraobserver k was observed in the Universal classification (0.61), followed by Fernández (0.59), Frykman (0.55) and AO/ASIF (0.49). The interobserver agreement was unsatisfactory in all classifications. The Fernández classification showed the best agreement (0.44) and the worst was the Frykman classification (0.26). CONCLUSION: The low agreement levels observed in this study suggest that there is still no classification method with high reproducibility.

Are distal radius fracture classifications reproducible? Intra and interobserver agreement / As classificações das fraturas do rádio distal são reprodutíveis? Concordância intra e interobservadores

CONTEXT AND OBJECTIVE: Various classification systems have been proposed for fractures of the distal radius, but the reliability of these classifications is seldom addressed. For a fracture classification to be useful, it must provide prognostic significance, interobserver reliability and intraobserver reproducibility. The aim here was to evaluate the intraobserver and interobserver agreement of distal radius fracture classifications. DESIGN AND SETTING: This was a validation study on interobserver and intraobserver reliability. It was developed in the Department of Orthopedics and Traumatology, Universidade Federal de São Paulo - Escola Paulista de Medicina. METHOD: X-rays from 98 cases of displaced distal radius fracture were evaluated by five observers: one third-year orthopedic resident (R3), one sixth-year undergraduate medical student (UG6), one radiologist physician (XRP), one orthopedic trauma specialist (OT) and one orthopedic hand surgery specialist (OHS). The radiographs were classified on three different occasions (times T1, T2 and T3) using the Universal (Cooney), Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF), Frykman and Fernández classifications. The kappa coefficient (κ) was applied to assess the degree of agreement. RESULTS: Among the three occasions, the highest mean intraobserver k was observed in the Universal classification (0.61), followed by Fernández (0.59), Frykman (0.55) and AO/ASIF (0.49). The interobserver agreement was unsatisfactory in all classifications. The Fernández classification showed the best agreement (0.44) and the worst was the Frykman classification (0.26). CONCLUSION: The low agreement levels observed in this study suggest that there is still no classification method with high reproducibility.

CONTEXTO E OBJETIVO: Para que as classificações das fraturas possam ser úteis, elas devem prover o prognóstico, apresentar concordância interobservador e reprodutibilidade intraobservador. O objetivo foi avaliar a concordância intra e interobservadores das classificações das fraturas do rádio distal. TIPO DE ESTUDO E LOCAL: Estudo de validação (concordância intra e interobservadores), desenvolvido no Departamento de Ortopedia e Traumatologia da Universidade Federal de São Paulo - Escola Paulista de Medicina (Unifesp-EPM), São Paulo, Brasil. MÉTODO: Foram avaliadas 90 fraturas do rádio distal com desvio por meio de radiografias por cinco observadores (um médico residente de Ortopedia do terceiro ano, um graduando do sexto ano de medicina, um médico radiologista, um ortopedista especializado em trauma e um ortopedista especializado em cirurgia da mão) em três momentos diferentes, empregando as classificações Universal (Cooney), AO/ASIF (Osteosynthesfragen/Association for the Study of Internal Fixation), Frykman e Fernández. Aplicou-se o coeficiente de concordância kappa (κ) para avaliação das classificações. RESULTADOS: O maior κ intraobservador médio, se considerarmos os três momentos, foi da classificação Universal (κ = 0,61), seguida da Fernández (κ = 0,59), Frykman (κ = 0,55) e AO/ASIF (κ = 0,49). A concordância interobservador foi insatisfatória em todas as classificações. A classificação de Fernández mostrou a melhor concordância (κ = 0,44) e a pior foi a de Frykman (κ = 0,26). CONCLUSÃO: Os baixos níveis de concordância observados neste estudo sugerem que atualmente ainda não há um método de classificação plenamente reprodutível.

Colles' fracture.

Many people "slip and fall", especially in the icy areas of the winter season. To prevent an injury to the head, most people put their hand out to hit the ground first, so the wrist usually gets injured. The most frequent injury from this type of "intervention" is a fracture to the distal radius and/or ulna, which is frequently called a "Colles' fracture."

Recognising and treating Colles' type fractures in emergency care settings.

In this article, the author explains how to identify a Colles' type fracture, explains how to insert a haematoma block, and gives a step by step guide to reducing this type of fracture.

[Loco typico radius fractures--personal experience]. / Fractura radii loco typico--nasa iskustva.

Fractura radii loco typico (FRLT) is the fracture of the distal radius. That is the one of the most frequent fractures of locomotor system with the widest range of treatment in traumatology. Therapy depends on the stability of the fracture: nonoperative or operative. We analysed the five-year experience of our Department of Traumatology where more than 1500 patients with FRLT have been treated in the urgent surgery clinic and 126 of them were hospitalized. In our study we evaluated the results of the operative treatment and postoperative functional status of a treated wrist. According to the A-O classification, we hospitalized 36 patients with A type, 28 patients with B type, and 62 patients with C type of FRLT. We operated 80 patients. The postoperative functional status of a treated wrist was excellent or good in 64 patients and good in 16 patients. The treatment of FRLT depends on the type and the complications of the fracture and the age of the patients. Operative therapy is indicated in the unstable FRLT or after an inadequate nonoperative treatment.

Distal radius fractures in adults.

Although distal radius fractures are a common injury in the elderly and young adult population, the classification, treatment options, and assessment of outcomes of these fractures remain controversial. Since there is no uniform fracture classification system, it is difficult to compare studies. An evidence-based model of management needs to be developed.

Bone density and geometric properties of the distal radius in displaced and undisplaced Colles' fractures: quantitative CT in 70 women.

We examined cortical and trabecular bone density and geometric properties of the unfractured distal radius in 70 women with recent Colles' fractures, using multilayer peripheral quantitative computed tomography (pQCT). We found that cortical volumetric density, cortical area and mean cortical thickness were lower in the displaced than in the undisplaced fractures, suggesting that the cross-sectional volumetric density and geometric properties of cortical bone may be essential in determining the severity of a Colles' fracture. We also compared lumbar spine and femoral neck bone mineral density (BMD) and the occurrence of osteoporosis in the displaced and undisplaced fracture groups and found no significant difference, which suggests that displacement of a Colles' fracture is not associated with general osteoporosis.

Clodronate increases mineralization of callus after Colles' fracture: a randomized, double-blind, placebo-controlled, prospective trial in 32 patients.

In a randomized study of 32 postmenopausal women with a Colles' fracture, we studied whether 8 weeks of treatment with clodronate, a bisphosphonate, could prevent posttraumatic osteopenia. The patients were treated with a plaster splint for 4 weeks. The bone mineral density (BMD) of the forearm bones was measured at 2 levels with dual-energy x-ray absorptiometry (DEXA) 2, 6 and 12 months after the fracture. At 2 months, in the clodronate group, there was a median 53% higher BMD in the fracture region of the radius than in the uninjured radius. In the placebo group, we found a 33% higher BMD in the fractured radius at that level than in the uninjured radius. This increase in BMD of the fractured radius, caused by clodronate, was statistically significant. At 12 months, the BMD of the fracture side had been reduced by 17% and 12%, respectively, at that time it was still significantly increased in the clodronate group alone. In the ulna at the same level, we found no significant changes in BMD in either group on either side at any time. At 2 months, at the level between the distal and middle thirds, in the fractured radius, the median BMD was 7% lower in the clodronate group and 6% lower in the placebo group than in the uninjured radius. Although the reduction in BMD at that level was significant, there was no difference between the two treatment groups. At this level, the ulna on the fractured side showed a similar pattern, with a 5% lower BMD in the clodronate group and a 4% lower BMD in the placebo group. This osteopenia showed a small but significant progression on the fractured side after 6 and 12 months.

Internal fixation of distal radius fractures with dorsal dislocation: pi-plate or two 1/4 tube plates? A prospective randomized study.

BACKGROUND: Severely comminuted distal radius fractures can be treated by different methods. Our routine procedure in dorsal dislocated fractures is the dorsal stabilization with two 1/4 tube plates. The new pi-plate is an other device that matches optimally the anatomy of the distal radius and allows a near half-circumferential dorsal buttress of comminuted intraarticular and extra-articular radial fractures. METHODS: In a prospective randomized study, comminuted distal radius fractures with dorsal displacement were stabilized either with two 1/4 tube plates or with the pi-plate. All patients were reviewed at 1, 3, and 6 months after surgery by thorough clinical examination and standard radiographs of both wrists. Results were analyzed and compared in both groups. RESULTS: Subjective and objective results in the pi-plate group are disappointing. Although optimal anatomic results were achieved, the complication-rate was high (14.3%) and the range of motion was limited. At final review, extension and flexion of the injured wrist had recovered to an average of 67% of the normal, contralateral side. Radial and ulnar deviation were limited to 64%, whereas pronation and supination reached 89% and 87%, respectively. Overall, results were good to excellent only in 56%. In a comparable group of patients with similar fractures and stabilization with two 1/4 tube plates, 82% of patients achieved excellent to good results, wrist motion was significantly better (p < 0.05), and no complications occurred. CONCLUSION: With open reduction, cancellous bone grafting, and internal plate fixation in comminuted distal radial fractures, excellent results can be achieved. In our experience, we cannot recommend the 7pi-plate in its current shape and prefer to stabilize distal radius fractures and dorsal fragment dislocations with two 1/4 tube plates.

Trans-styloid fixation of fractures of the distal radius. A prospective randomized comparison between 6- and 1-week postoperative immobilization in 60 fractures.

We performed a prospective randomized study on 60 patients with dorsally displaced extra-articular or noncomminuted intraarticular fractures of the distal radius. All 60 fractures were treated by closed reduction and Kirchner wire trans-styloid fixation. 30 patients had 1 weeks' postoperative immobilization and 30 patients had 6 weeks' immobilization. All patients had a clinical and radiographic review at 6 weeks and at 1 year after the operation. Pain, range of movement and grip strength were tested clinically, and changes in dorsal tilt, frontal radial deviation, ulnar variance, and radial shortening were assessed radiographically. Rates of complications were the same in both groups. At follow-up, pain was similar in both groups and range of motion and grip strength were somewhat better after early mobilization--in comparison with the opposite wrist--but this was statistically significant only for ulnar deviation. The postoperative radiographic reductions were similar in both groups, with no differences in loss of reduction after bone healing. Therefore, in Colles' fractures, trans-styloid fixation with two K-wires seems to give a stable osteosynthesis, which does not need additional immobilization with a plaster cast.

Fractures of the distal forearm in young adults. An epidemiologic description of 341 patients.

We describe the epidemiology of all distal radial fractures in young adults (men 20-59 years, women 20-49 years) in Lund (1992-95) and Malmö (1994-95), Sweden. During the study period, there were 341 patients with 346 fractures in the two cities, found through the Hospital Register of Diagnoses in Lund and the register of the Radiology Department in Malmö. More than half of the fractures were dislocated and 2/3 of the cases involved the radiocarpal or radioulnar joints, in contrast to the predominantly extra-articular fractures in the elderly. There was an even distribution between sexes and the fractures were mainly caused by a severe trauma, i.e., more than a simple fall, most often sports injuries in January, February and May. Our findings suggest that distal radial fractures in nonosteoporotic young adults should be regarded as a special entity, at least in epidemiological studies. Possibly they also require treatment differing from that for osteoporotic fractures.

Intra-articular fractures of the distal aspect of the radius.

Intra-articular distal radius fractures are a heterogeneous group of injuries with different fracture patterns. The existing classification systems are helpful for describing the fractures but not for assessing their stability or for deciding which surgical approach to use. Patients who have a fracture with at least 1.0 mm of displacement of the articular surface may benefit from open surgical treatment. Improved diagnostic imaging with CT is helpful for fracture classification and surgical planning. The options for surgical treatment include limited open reduction and internal fixation, arthroscopically assisted internal fixation, and open reduction and internal fixation. The surgical approach is determined on the basis of the initial displacement of the fracture. Patients who have a displaced fracture of the volar rim may benefit from a volar approach; those who have a dorsally displaced fracture, from a dorsal approach; and those who have an impacted fracture such as a die-punch fracture, from a dorsal approach that provides better visualization of the articular surface. The long-term functional outcome is determined in part by the severity of the fracture as defined by the amount of comminution, the initial severity of displacement, and the number of fracture fragments. The accuracy of the reconstruction of the articular surface, with the goal of establishing congruency to within 1.0 mm, is also important in order to minimize the risk of late osteoarthrosis. Of all of the extra-articular parameters, restoration of the length of the radius is the most important for enhancing recovery of motion and grip strength and for preventing problems involving the distal radioulnar joint--the so-called forgotten joint in distal radial fractures.

Management of comminuted fractures of the distal radius in the adult. Conservative or surgical?

Displaced fractures of the distal radius are difficult to treat successfully by traditional nonoperative methods. The goal in the management of these fractures is to achieve extraarticular alignment and an articular step off of less than 2 mm. Cast immobilization has been supplemented with pins and plaster technique and external fixators. Percutaneous are limited open reduction techniques, combined with wrist arthroscopy, have been shown to be useful in the management of intraarticular distal radius fractures. Despite these advances, there are still a significant number of fractures in which the articular surface cannot be reconstructed without open reduction and internal fixation. The main objective is to restore articular integrity as perfectly as possible. Attention to meticulous surgical technique will facilitate good results. When articular restoration cannot be accomplished, early arthrodesis or arthroplasty should be indicated. In the absence of osteoarthritis, intraarticular osteotomy can be used for intraarticular malunions with a step off greater than 2 mm. Radius malalignment usually requires a dorsal opening wedge osteotomy, insertion of a corticocancellous graft, and a dorsal buttress plate. Early recognition and treatment of distal radioulnar joint injuries associated with fractures of the distal radius are paramount to reduce the incidence of painful sequelae and functional deficits.

Poor interobserver reliability of AO classification of fractures of the distal radius. Additional computed tomography is of minor value.

Interobserver reliability of the AO system of classification of fractures of the distal radius was assessed using plain radiographs and CT. Five observers classified 30 Colles'-type fractures using only plain radiographs; two months later they were reclassified using CT in addition. Interobserver reliability was poor in both series when detailed classification was used. By reducing the categories to five, interobserver reliability was slightly improved, but was still poor. When only two AO types were used, the reliability was moderate using plain radiographs and good to excellent with the addition of CT. The use of CT as well as plain radiographs brings interobserver reliability to a good level in assessment of the presence or absence of articular involvement, but is otherwise of minor value in improving the interobserver reliability of the AO system of classification of fractures of the distal radius.

AO and Frykman's classifications of Colles' fracture. No prognostic value in 652 patients evaluated after 5 years.

We retrospectively assessed hand and forearm symptoms of 652 patients with a Colles' fracture, 5 years after the fracture, using a questionnaire. The contralateral forearm, which was free of major injuries or illnesses, was used as control. Forearm and hand symptoms were common and only one quarter of the fractured forearms were completely free of symptoms at the time of review, whereas four fifths of the control forearms had no symptoms. Nearly half of the patients complained of impairment in various activities and 8% had had to give up leisure activities or make special arrangements at work. Demographic, and most of the fracture-related factors, were not associated with the symptoms. Neither AO nor Frykman's radiographic classifications of the primary fracture were of any use for predicting the clinical outcome.

Comparative classification for fractures of the distal end of the radius.

As suggested by Muller, a useful classification system for distal radius fractures must consider the severity of the bone lesion and serve as a basis for treatment and for evaluation of outcome. Although these fractures have long been considered to be Colles or Smith's fractures, they have been subjected to extensive scrutiny in order to define fracture morphology and treatment considerations. This review highlights a number of contemporary classification systems for distal radius fractures, including the systems of Older et al., the Comprehensive Classification of fractures, the Melone intra-articular classification system, and that of Fernandez.

Intracarpal soft-tissue lesions associated with an intra-articular fracture of the distal end of the radius.

Sixty patients who had a displaced intra-articular fracture of the distal end of the radius were managed with manipulative reduction and internal fixation performed under both fluoroscopic and arthroscopic guidance. According to the AO/ASIF classification system, seven fractures were type B1, two were type B2, three were type B3, thirteen were type C1, twelve were type C2, and twenty-three were type C3. Forty-one patients (68 per cent) had soft-tissue injuries of the wrist, including tears of the triangular fibrocartilage complex (twenty-six patients), the scapholunate interosseous ligament (nineteen), and the lunotriquetral interosseous ligament (nine). Thirteen patients had two soft-tissue injuries. Intracarpal soft-tissue injuries were identified most frequently in association with fractures involving the lunate facet of the distal articular surface or the radius.