Risk factors for failure after cementless femoral revision THA: a consecutive series of 105 cases.

INTRODUCTION: Cementless femoral revision total hip arthroplasty (RTHA) after periprosthetic fracture, aseptic loosening or infection is a challenging surgical procedure. The aim of this study was to evaluate the incidence and reasons for failure after two-stage septic revision, periprosthetic fracture or aseptic loosening that may reveal a rationale for cementless RTHA in two-stage revisions. MATERIALS AND METHODS: A consecutive series of 105 cases using cementless femoral revision prostheses were evaluated retrospectively. Indications for revision were 39 two-stage revisions after infection, 49 aseptic loosenings, and 17 periprosthetic fractures. A Kaplan-Meier analysis was performed using infection with or without removal of the implant as an endpoint. RESULTS: Incidence of infection with or without implant removal was significantly higher in patients treated for periprosthetic fractures compared to two-stage revisions or aseptic loosening (log-rank P < 0.0001). The mean follow-up period was 6.4 (2.0-13.7) years. Using infection with or without implant removal as the endpoint, 12 patients were diagnosed after the index operation resulting in a cumulative risk after 13.7 years of 29.9% (95% CI 0-61.2). CONCLUSION: Cementless revision using a modular tapered device is reliable with respect to reinfection risk in two-stage procedures.

Different injury patterns after snowboard in children and adolescents.

BACKGROUND: Snowboarding is a very common sport especially among young adults. Common injuries are hand, wrist, shoulder and ankle injuries. PURPOSE: of this study was to analyze different injury pattern in children and young adults comparing with adults. METHODS: Patients who were admitted for ambulant or stationary treatment as a result of injury practicing snowboard received a questionnaire and were divided into three groups (children, young adults and adults) according to their age. Between october 2002 and may 2007 1929 injured snowboard sportsmen were included in the study. Data such as location, date and time of accident as well as information about the slope were carried out. In addition snowboard skills were classified and patients were questioned whether they wore special protectors. RESULTS: 32.5% of injured patients were female (n = 626) and 67.5% male (n = 1303) with a mean age of patients of 21.9 (7-66) years. 13% of all patients were in group I (children), 19.2% in group II (young adults) and 67.8% in group III (adults).Most common injuries with 60% of all accidents were injuries of the hand wrist especially in children beginning with snowboard sports. Injuries on the regular track were most common followed by jumps in the kicker park and rails in the fun-park. 20.6% in group I, 13.6% in group II and 12.8% group III did not wear any protectors. CONCLUSION: Children and adolescents presented different injury patterns than adults. Young participants of up to 14 years of age are endangered especially during the first days of learning this sport. Further development of protectors with regard to biomechanical characteristics is important to achieve an optimal protective effect. LEVEL OF EVIDENCE: 2b.

Arthrodesis for septic arthritis of the ankle: risk factors and complications.

INTRODUCTION: Septic ankle joint arthrodesis is a good therapeutic option in cases of infection after trauma or orthopedic surgical procedures. Many different procedures have been described, but external fixation seems to be standard. Aim of this study is to identify risk factors for complications in septic ankle joint arthrodesis with the external AO frame fixator. MATERIALS AND METHODS: Patients who received septic ankle joint arthrodesis between January 2008 and December 2012 were included in this study. Patients were evaluated clinically and with radiographs or CT scans. RESULTS: Follow-up of 74 of 79 patients with an external AO frame fixator could be evaluated; follow-up was 411 days (105-991). The mean age at surgery was 57.7 years (19-87). At this time, complications occurred in 41 patients (52 %) with wound healing problems (17 patients, 22 %) and non-union (12 patients, 15 %), and some needed surgical revision. In our collective, men had a significant higher non-union rate (p = 0.031), age or BMI showed no difference. Patients with diabetes and alcohol consumption showed a higher risk for complications (p = 0.049 and p = 0.031, respectively). 62 % of primary arthrodesis showed union, whereas in the case of revision, arthrodesis only 39 % showed union. CONCLUSIONS: Septic ankle joint arthrodesis with the external AO frame fixator is a probable tool to achieve union. This study showed that there is a high complication rate and some risk factors for complications could be identified. A blinded and prospective study is needed to compare intramedullary nailing and external fixation to evaluate the possible advantage of intramedullary devices in septic ankle arthrodesis.

[The UniSpacer™: correcting varus malalignment in medial gonarthrosis. Preliminary results]. / UniSpacer™: corrección de la desalineación en varo en la gonartrosis medial. Resultados preliminares.

While options for operative treatment of leg axis varus malalignment in patients with medial gonarthrosis include several established procedures, such as unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA), or high tibial osteotomy (HTO), so far there has been little focus on a less invasive option introduced more recently: the UniSpacer™ implant, a modern, self-centering, metallic interpositional device for the knee. This study evaluates whether alignment correction can be achieved by UniSpacer™ arthroplasty as well as alignment change in the first 5 postoperative years is evaluated. Antero-posterior long leg stance radiographs of 15 legs were digitally analyzed to assess alignment change: two relevant angles and the deviation of the mechanical axis of the leg were analyzed before and after surgery. Additionally, the change of the postoperative alignment was determined one and five years postoperatively. Analyzing the mechanical tibiofemoral angle, a significant leg axis correction was achieved, with a mean valgus change of 4.7±1.9°; a varus change occurred in the first postoperative year, while there was no significant further change of alignment seen five years after surgery. The UniSpacer™ corrects malalignment in patients with medial gonarthrosis; however, a likely postoperative change in alignment due to implant adaptation to the joint must be considered before implantation.

UniSpacer™: corrección de la desalineación en varo en la gonartrosis medial. Resultados preliminares / The UniSpacer™: correcting varus malalignment in medial gonarthrosis. Preliminary results

Aunque entre las opciones del tratamiento operatorio de la desalineación en varo del eje de la pierna en pacientes con gonartrosis medial se incluyan varios procedimientos consolidados como, por ejemplo, la artroplastia unicompartimental de rodilla (AUR), la artroplastia total de rodilla (ATR) o la osteotomía tibial valguizante (OTV), hasta ahora no se ha prestado demasiada atención a una opción menos invasiva de reciente introducción: el implante UniSpacer™, un dispositivo interposicional, autocentrador y metálico para la rodilla. En el presente estudio (14 pacientes, 15 rodillas) nos dedicamos a evaluar si es posible corregir la alineación realizando una artroplastia con el UniSpacer™, así como el cambio de alineación que se produce en los 5 años posteriores a la intervención quirúrgica. Se han analizado digitalmente las radiografías anteroposteriores en carga de 15 rodillas para calcular el cambio de alineación: se analizaron 2 ángulos relevantes y la desviación del eje mecánico de la pierna antes y después de la intervención quirúrgica. Además, se determinó el cambio de la alineación posoperatoria transcurridos entre uno y 5 años. Al analizar el ángulo tibiofemoral mecánico, observamos que se logró una corrección significativa del eje de la pierna, con una media de cambio en valgo de 4,7±1,9°. Durante el primer año posterior a la intervención quirúrgica se produjo un cambio en varo, aunque no se detectó ningún cambio adicional significativo de alineación durante los 5 años posteriores a la intervención quirúrgica. El UniSpacer™ corrige eficientemente la desalineación de algunos pacientes con gonartrosis medial. No obstante, antes de proceder a la implantación deberá tenerse en cuenta la posibilidad de que se produzcan cambios posoperatorios adicionales no inmediatos de la alineación como consecuencia de la adaptación del implante (AU)

While options for operative treatment of leg axis varus malalignment in patients with medial gonarthrosis include several established procedures, such as unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA), or high tibial osteotomy (HTO), so far there has been little focus on a less invasive option introduced more recently: the UniSpacer™ implant, a modern, self-centering, metallic interpositional device for the knee. This study evaluates whether alignment correction can be achieved by UniSpacer™ arthroplasty as well as alignment change in the first 5 postoperative years is evaluated. Antero-posterior long leg stance radiographs of 15 legs were digitally analyzed to assess alignment change: two relevant angles and the deviation of the mechanical axis of the leg were analyzed before and after surgery. Additionally, the change of the postoperative alignment was determined one and five years postoperatively. Analyzing the mechanical tibiofemoral angle, a significant leg axis correction was achieved, with a mean valgus change of 4.7±1.9°; a varus change occurred in the first postoperative year, while there was no significant further change of alignment seen five years after surgery. The UniSpacer™ corrects malalignment in patients with medial gonarthrosis; however, a likely postoperative change in alignment due to implant adaptation to the joint must be considered before implantation (AU)

Multiple Acetabular Revisions in THA - Poor Outcome Despite Maximum Effort.

A consecutive series of 52 acetabular revisions was evaluated retrospectively. Inclusion criteria for all patients were at least one former exchange of the acetabular component. Reconstruction was performed with reliable techniques and implants other than extensively porous coated device (e.g. tantalum). The mean follow up was 5.63 (0.01-14.05) years. Cumulative survival at 14.05 years with removal of the acetabular component due to aseptic loosening or the worst case criterion (removal of the acetabular component for any cause and/or lost to follow-up) as the end point was 66.38 (95 % C.-I.: 47.80-84.96) % and 58.42 (95 % C.-I.: 41.01-75.83) %, respectively. The cumulative survival rate with mechanical failure of the acetabular reconstruction as the endpoint was significantly lower in patients with two or more previous revisions in comparison to those with only one former procedure (log rank test: p=0,0112 respectively). The mean Merle d'Aubignée-score improved from 7.3 (0-14) preoperatively to 10.6 (0-17) points at latest follow up examination.Survival of acetabular reconstructions with common techniques and implants is decreasing with the number of previous revisions. This may cause major concerns with regard to the rising number of patients needing repeated revisions. Maximizing durability of primary THA, precise preoperative planning as well as improved techniques and implants for revision may decrease this problem in the long term.

The use of a femoral revision stem in the treatment of primary or secondary bone tumours of the proximal femur: a prospective study of 31 cases.

Endoprosthetic reconstruction following resection of 31 tumours of the proximal femur in 30 patients was performed using a Wagner SL femoral revision stem. The mean follow-up was 25.6 months (0.6 to 130.0). Of the 28 patients with a metastasis, 27 died within a mean follow-up period of 18.1 months (0.6 to 56.3) after the operation, and the remaining patient was excluded from the study 44.4 months post-operatively when the stem was removed. The two patients with primary bone tumours were still alive at the latest follow-up of 81.0 and 130.0 months, respectively. One stem only was removed for suspected low-grade infection 44.4 months post-operatively. The worst-case survival rate with removal of the stem for any cause and/or loss to follow-up was 80.0% (95% confidence interval 44.9 to 100) at 130.0 months. The mean Karnofsky index increased from 44.2% (20% to 70%) pre-operatively to 59.7% (0% to 100%) post-operatively, and the mean Merle d'Aubigné score improved from 4.5 (0 to 15) to 12.0 (0 to 18). The mean post-operative Musculoskeletal Tumour Society score was 62.4% (3.3% to 100%). The Wagner SL femoral revision stem offers an alternative to special tumour prostheses for the treatment of primary and secondary tumours of the proximal femur. The mid-term results are very promising, but long-term experience is necessary.

[Cement-free diaphyseal fixation principle for hip shaft exchange in large bone defects--analysis of 12 years experience with the Wagner revision shaft]. / Das zementfreie diaphysäre Verankerungsprinzip für den Hüftschaftwechsel bei grossen Knochendefekten--Analyse von 12 Jahren Erfahrung mit dem Wagner-Revisionsschaft.

PURPOSE: Considering the increasing incidence of revision for failed total hip arthroplasty, we evaluated if the principle of uncemented diaphyseal fixation which is realised with the Wagner SL revision stem, can solve the technical problems of significant bone loss of the proximal femur and can offer good preconditions for bony restoration in the medium term. METHODS: A consecutive series of 129 femoral revisions with the Wagner SL revisions stem was evaluated. In 87 cases, the acetabular component was revised simultaneously. The revision was indicated in 97 cases of aseptic loosening, in 13 periprosthetic fractures (12 aseptic and 1 septic hip), in 16 cases of septic loosening and in 3 Girdlestone-hips after chronic deep infection. At the time of revision, the mean age of the patients was 64.9 (36.7-86.3) years. For classification of the preoperative defects, both the classification system proposed by Pak et al. and our own classification system were used. RESULTS: The mean period of time between operation and latest follow-up examination, rerevision, or death of the patient was 5.4 years (0.13-11.7 years). Six revision stems required rerevision because of malpositioning (1), significant subsidence (1), periprosthetic fracture (1), and deep infection (3). The mean Merle d'Aubigné score improved from preoperatively 7.7 points to 14.8 at follow-up. Cumulative survival (end point removal of the stem for any cause) was 94.4 percent at 11.7 years. A clear, good, or excellent bony restoration of the proximal femur was seen in 87.6 percent of the cases. The cumulative survival of the revised acetabular components was 97.7 percent at 11.7 years and for the non-revised cups it was 86.9 percent at 10.9 years. CONCLUSION: Due to the encouraging results with the Wagner revision stem, the principle of uncemented diaphyseal fixation seems to us to be able to solve most of the technical problems in cases of significant bone loss and obviously offers good preconditions for bony restoration. Our own classification system was effective and useful for preoperative planning.

Femoral revision with the Wagner SL revision stem : evaluation of one hundred and twenty-nine revisions followed for a mean of 4.8 years.

BACKGROUND: It is difficult to achieve a successful revision total hip replacement when a patient has severe proximal femoral bone loss. The Wagner SL revision stem has some theoretical advantages, but the durability of this prosthesis is not known. METHODS: We reviewed the results of 129 revisions of the femoral component with a Wagner SL revision stem in 123 patients. The indication for revision was aseptic loosening in ninety-seven hips, periprosthetic fracture in thirteen (one of which also had an infection), and septic loosening in sixteen. In the three remaining hips, a Wagner revision stem was inserted during a second-stage reimplantation after the performance of a Girdlestone resection arthroplasty to treat chronic deep infection. The prerevision defects were classified with the system described by Pak et al. as well as with our system. A functional evaluation of the patients and a survival analysis of the revision stems were performed. RESULTS: The mean duration of follow-up was 4.8 years (range, two months to 11.1 years). Six revision stems required repeat revision. With removal of the stem for any cause or the worst case (removal of the stem for any cause and/or lost to follow-up) as the end point, cumulative survival at 11.1 years was 93.9% and 92.8%, respectively. The mean Merle d'Aubigné score improved from 7.7 points preoperatively to 14.8 points at the latest follow-up examination. The most recent radiographs showed good or excellent restoration of the proximal part of the femur in 113 hips (88%). CONCLUSIONS: Because of the encouraging results of implantation of this femoral component with distal fixation, we will continue to use it in the majority of femoral revisions. However, the need for regular follow-up remains, since the rate of complications such as osteolysis of the femur, aseptic loosening, periprosthetic fracture, and late infection may increase in the future.