Paprosky Classification System Research Articles

Management of Severe Bone Defects in Femoral Revision following Total Hip Arthroplasty.

Treatment of femoral bone defects continues to be a challenge in revision total hip arthroplasty (THA); therefore, meticulous preoperative evaluation of patients and surgical planning are required. This review provides a concise synopsis of the etiology, classification, treatment strategy, and prosthesis selection in relation to femoral bone loss in revision THA. A search of literature was conducted for identification of research articles related to classification of bone loss, management of femoral revision, and comparison of different types of stems. Findings of a thorough review of the included articles were as follows: (1) the Paprosky classification system is used most often when defining femoral bone loss, (2) a primary-length fully coated monoblock femoral component is recommended for treatment of types I or II bone defects, (3) use of an extensively porouscoated stem and a modular fluted tapered stem is recommended for management of types III or IV bone defects, and (4) use of an impaction grafting technique is another option for improvement of bone stock, and allograft prosthesis composite and proximal femoral replacement can be applied by experienced surgeons, in selected cases, as a final salvage solution. Stems with a tapered design are gradually replacing components with a cylindrical design as the first choice for femoral revision; however, further confirmation regarding the advantages and disadvantages of modular and nonmodular stems will be required through conduct of higher-level comparative studies.

Both Acetabular and Femoral Reconstructions With Impaction Bone Grafting in Revision Total Hip Arthroplasty: Case Series and Literature Review

BackgroundExtensive bone loss on femur and acetabulum posed a big challenge to orthopedists in total hip revision surgeries. Impaction bone grafting (IBG) as a valuable bone preservation technique could effectively address this problem. Either IBG revision on the femoral or acetabular side was well studied, while its use on both sides in one operation was not. The aim of this study is to present the outcomes of IBG on both femoral and acetabular sides at first-time hip revision. MethodsWe retrospectively reviewed 8 patients (mean follow-up of 5.8 years) undergoing first-time revision with IBG on both acetabular and femoral sides at our institution. The Paprosky classification system was used to classify bone defects. Freeze-dried allografts and cemented prostheses were used in all patients. Postoperative complications and rerevision rates were reported. ResultsFive patients presented a Paprosky type IIC acetabular defect, 3 with a type IIIB, IIIA, and IIC defect, respectively. Three patients presented with a type IV femoral defect, 3 with a type IIIB defect, and 2 with a type II defect. Two patients developed complications, while one had an intraoperative femoral fracture and one had delayed wound healing. At the latest follow-up, no patient had rerevisions or operations related to the prosthesis. ConclusionsIBG in combination with cemented prosthesis is a profitable biological reconstruction revision technique that could provide satisfying midterm outcomes. We first propose the use of blood clots mixed with bone grafts for potential bone incorporation enhancement, while its specific effects need to be verified in further studies.

Reconstruction options and outcomes for acetabular bone loss in revision hip arthroplasty.

Revision total hip arthroplasty in the setting of acetabular bone loss is a challenging procedure and requires a solid understanding of current acetabular reconstruction options. Despite major developments in the field of revision hip surgery in recent decades, reconstruction of acetabular defects remains a major problem in order to achieve primary stability and durable fixation without sacrificing additional bone stock. Although there are several ways to classify acetabular bone defects, the Paprosky classification system is the most commonly used to describe the defects and guide treatment strategy. An understanding of the bone defects associated with detailed pre-operative assessment and planning are essential elements in order to achieve satisfactory outcomes. Multiple acetabular reconstructive options are currently available including impaction bone grafting with metal mesh, reinforcement rings and antiprotrusio cage, structural allografts, cementless hemispherical cups, extra-large “jumbo cups”, oblong cups, modular porous metal augments, cup-cage constructs, custom- made triflange cups, and acetabular distraction. To date, debate continues as to which technique is most effective due to the lack of long-term studies of modern reconstruction systems. Further long-term studies are necessary to assess the longevity of the different implants. The purpose of this study was to review the current literature and provide a comprehensive understanding of the available reconstruction options with their clinical outcomes.

Using personalized 3D printed Titanium sleeve-prosthetic composite for reconstruction of severe segmental bone loss of proximal femur in revision total hip arthroplasty

Rationale:Allograft-prosthetic composites (APCs) and proximal femoral replacement have been applied for reconstruction of severe segmental femoral bone loss in revision total hip arthroplasty. The outcomes are encouraging but the complication rate is relatively high. Considering the high complication rates and mixed results of APCs and megaprosthesis, we presented a case using personalized 3D printed Titanium sleeve-prosthetic composite for reconstruction of segmental bone defect.Patient concerns:A 73-year-old woman presented to the emergency department on account of acute severe pain of the left hip without history of trauma. She had undergone a cemented total hip arthroplasty for osteonecrosis of femoral head at the left side in 2000. In 2013 she underwent a cemented revision total hip arthroplasty as a result of aseptic loosening of hip prosthesis. She denied obvious discomfort prior to this episode since the revision surgery in 2013.Diagnosis:According to the clinical history, imaging and physical examination, we confirmed the diagnosis of severe segmental bone loss of proximal femur and fracture of prosthetic stem. The femoral bone defect was evaluated using the Paprosky classification system and rated as Type 3B, and the acetabular bone defect was rated as Type 2C.Interventions:In this study, we present the first case of severe segmental bone loss of proximal femur in revision total hip arthroplasty that was successfully treated using personalized 3D printed Titanium sleeve-prosthetic compositeOutcomes:At the 2-year follow-up, the patient was symptom free with a Harris Hip Score of 91. Radiographs showed excellent osteointegration between the interface of sleeve-prosthetic composite and the host bone, with no signs of implant loosening or subsidence.Lessons:Despite the absence of long term results of 3D printed Titanium sleeve-prosthetic composite reconstruction, the good clinical and radiological outcome at 2 years follow up implied its potential role for reconstruction of segmental femoral bone defect in revision THA.

Clinical application of uncemented distal stem fixation for revising femoral prosthesis of hip arthroplasty in elderly patients

Objective To evaluate the effectiveness of uncemented distal stem fixation for elderly patients needing revision of femoral prosthesis of hip arthroplasty. Methods From July 2005 to January 2013, 22 patients(12 males and 10 females)aged from 70 to 85 years(average: 76 years old)with aseptic loosening of the femoral stem undergone revision via uncemented distal stem fixation were enrolled into this study.Of all patients, 10 had revision on the right side and 12 on the left side; 11 patients received artificial replacement of the femoral head; 9 had total hip replacements; 2 had femoral fractures.According to the Paprosky classification system, 2 cases were type I, 12 were type Ⅱ, 6 were type ⅢA, and 2 were type ⅢB.Femoral stems for revision included MP(Link)and Solution(Depuy). The Harris score, clinical and radiological results were retrospectively analyzed. Results All patients were followed up for 48 to 78 months(mean: 61 months). The average Harris score increased from 38(25-46)to 87(76-94). All prostheses were initially stable, and no infection, dislocation or complication like deep venous thrombosis was observed after revision.All patients were able to walk without assistance; two of them had minor claudication; radiographs after surgery showed well-positioned implants with increased bone density and thickness around the prosthesis and without loosening or subsidence. Conclusions Reliable axial and anti-rotational stability can be achieved by using uncemented distal stem fixation, with good short-and medium-term clinical results for revision in elderly patients with less severe bone defects than those in Paprosky Ⅳ. Key words: Hip joint; Revision; Femur

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

PurposeThe 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 MethodsBone 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).ResultsOverall 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.ConclusionUsing 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.

Evaluation and Treatment of Femoral Osteolysis Following Total Hip Arthroplasty.

➢ Femoral osteolysis following total hip arthroplasty is a common problem that may lead to implant loosening, necessitating a revision surgical procedure.➢ The location of bone loss, the residual proximal femoral bone stock, and the remaining isthmus available for diaphyseal fixation are factors used to determine the management plan.➢ The Paprosky classification system may be used to determine bone loss and to plan a treatment strategy.

Classifying femoral bone deficiency: Picking the right tool for the job

The number of total hip arthroplasties continues to increase each year, and with it grows the demand for surgeons prepared to manage complicated revisions. To date, the Paprosky classification system is the most commonly used, well described, and successfully implemented classification system for periprosthetic femoral bone loss. In this review, the Paprosky femoral bone loss classification is presented in detail, using illustrative examples of cases encountered by the contributing authors.

Impaction morselized allografting combined with cementless long stem for femoral defects in femoral component revision

To retrospectively analyze the clinical and radiological results of the impaction morselized allografting combined with cementless long stem for femoral component revision in patients with significant bone loss. From July 2003 to June 2009, 27 patients (27 hips) underwent revision hip arthroplasty in femurs with bone defect using impaction allografting and cementless components. There were 15 male and 12 female with mean age of 67 years. According to the Paprosky classification system, the bone defects in femur were classified into type II in 3 cases, type III in 21 cases and type IV 3 cases. The patients were followed up postoperatively to observe the clinical and radiological results, and if there had the stem subsidence, periprosthetic fracture, infection and other complications. Twenty-three patients were followed up. The mean follow-up time was 26 months. Harris score improved from 43 points pre-revision to 83 points at the final follow-up. No femoral stem loosening and failure occurred. There were 4 stem with a mean 3.3 mm subsidence. One case had an acute infection after revision and treated successfully by debridement and drainage, antibiotics. No stem need further revision. Radiographic analysis showed all the revised stem was stable, and graft incorporation was seen in at least 1 zone in 100% of the femurs. The results of this study demonstrates that femoral support and vigorous impaction grafting combined with cementless long stem results in an good intermediated-term clinical effects.

Revision Total Hip Arthroplasty Using a Wagner Revision Stem

Purpose: We evaluated the results of revision total hip arthroplasty using a Wagner revision femoral stem. Materials and Methods: We enrolled 54 patients who underwent hip arthroplasty using a Wagner revision stem between 1996 and 2004. The mean age at revision surgery was 65.4 years and the mean follow up period was 7.2 years. There were 42 aseptic loosenings and 12 periprosthetic fractures. The pre-operative femoral defects were classified according to the Paprosky classification system. Clinical and radiological results were evaluated. Results: The mean Harris hip score improved from 43 preoperatively to 89 at the latest follow up. There were 2 cases with inguinal pain and 1 with thigh pain; in each case pain was reduced by medications. All cases showed endosteal bone formation around the stem. Five cases showed radiolucency in Gruen zones 1 and 7. Six cases had hips that showed subsidence (average=3.1 mm). There was 1 dislocation (1.8%) and 1 intraoperative periprosthetic fracture (1.8%). There were no re-revisions. Conclusion: Use of a Wagner revision femoral stem for revision total hip arthroplasty elicits satisfactory results including stable fixation of the stem, a low rate of subsidence, and a low rate of dislocation.

Femoral Revision with the Wagner SL Revision Stem

Purpose : To evaluate the results of revision total hip arthroplasty using a Wagner SL revision stem. Materials and Methods : This study reviewed 56 revisions of the femoral component performed using a Wagner stem in 55 patients between 1992 and 2001. The mean age of the patients at the time of the revision was 50 years. The mean follow up duration was 8.4 years (range, 5 to 12.5 years). The indication for revision was aseptic loosening in fifty-two hips, septic loosening in two and periprosthetic fractures in two. The pre-revisional femoral defects were classified according to the Paprosky classification system. A clinical evaluation and radiological assessment were performed. Results : The mean Harris hip score improved from 47 points preoperatively to 87 points at the latest follow-up. There were 5, 20, 22 and 9 hips of type I, II, IIIA and IIIB according to the Paprosky classification system. Fifty two hips (93%) showed stable stems at the latest follow-up radiographs. The mean vertical subsidence of the stem was 6.2 mm (range, 0 to 21 mm). Severe progressive vertical subsidence in three hips and an infection in one occurred requiring repeat revision. Conclusion : For severe proximal femoral bone loss, the conical femoral revision stem with a fully grit-blasted surface produced satisfactory results with distal press-fit fixation. We can expect a decrease in the rate of mechanical failure rate of the stem by reducing the subsidence derived from the stem design itself.

A comparison of the reliability and validity of bone stock loss classification systems used for revision hip surgery

Three femoral (Paprosky, American Academy of Orthopaedic Surgeons [AAOS], and Endo-Klinik) and 2 acetabular (Paprosky, AAOS) bone stock loss classification systems were evaluated for reliability. Four observers (2 consultants, 2 registrars) graded the bone loss in 25 patients using preoperative radiographs. Grading was repeated after a minimum of 2 weeks. Interobserver and intraobserver reliability was investigated. The κ statistic was used to assess levels of agreement. Intraobserver agreement ranged from poor to good. Interobserver agreement ranged from fair to moderate. The validity of the Paprosky classification system was evaluated, comparing preoperative bone stock loss assessment with intraoperative findings. Agreement levels of moderate (femoral classification system) to good (acetabular classification system) were achieved. Bone stock loss classification systems are shown to be inconsistent and unreliable.