Techniques for filling tibiofemoral bone defects during revision total knee arthroplasty.

There are a variety of options for filling defects during revision total knee arthroplasty: cement with or without screws, structural or morselized allograft, highly porous cones and sleeves, massive bone allograft or megaprostheses. Our goal is to describe the techniques for these procedures and their indications. Any necrotic bone, fibrous tissue or granulomas must be excised, and the bone freshened. The height of the joint line must be restored using trial components stabilized by stems. The defect is the space between the bone and each of the two components. Whether contained or not, it can be evaluated using the AORI classification. Cement alone or supplemented with screws, which is pressurized to penetrate the bone, is now only used in small defects less than 10mm in diameter, especially contained one. It is preferable to use morselized compacted bone graft instead. Augments are used to fill AORI type 2 defects less than 10 mm deep in a condyle. They can also be used to position the femoral component and sometimes the tibial one. For type 2 and 3 defects, bone allografts aim to reconstruct the skeleton. They can be used as trimmed fragments, as described by Engh who did hemispheric reaming to embed a femoral head into the defect. One can also compact or pack morselized bone graft around a stem. These reconstruction procedures are long and difficult. They are being done less and less since porous cones and sleeves were introduced, which are impacted after bone preparation. These sterile components are secured to the stem either mechanically or with cement, saving time. Once in place, bone grows into them. They provide metaphyseal anchoring that helps to reduce the stem's length. When the epiphysis is nearly all gone, the choices are a massive bone allograft or a megaprosthesis, although both have a high risk of infection and mechanical failure. The allograft must be trimmed to restore the height of the joint line and achieve a stable connection with the host bone. A long stem, always cemented into the allograft, is essential. In older patients, a megaprothesis is simpler to use and faster. The femur is better suited to massive reconstruction than the tibia, where coverage must be ensured along with extensor mechanism continuity. LEVEL OF EVIDENCE: V; expert opinion.

Techniques and outcomes of hip abductor reconstruction following tumor resection in adults.

The function of the abductor mechanism (AM) of the hip can be disturbed, or even compromised, following tumor resection in the hip area. The consequences are instability (limping, dislocation), pain and altered walking ability. Several reconstruction techniques can be used for the same AM sacrifice. After defining the AM, this lecture will discuss the best technique for a given type of bone and muscle resection. These reconstruction techniques depend on exactly where the AM was sacrificed. For zone 1 resections of the ilium and/or iliac gluteal insertions, reconstruction is often optional. When muscle from the AM is resected, especially when the gluteal tendon is detached from its trochanteric insertion, isolated reconstruction can be done or reconstruction in combination with a tendon allograft or an allograft and/or tendon transfer from the surrounding area. This sacrifice, whether followed by reconstruction or not, in most cases leads to a good functional outcome, except when a complete musculotendinous unit or the superior gluteal nerve is sacrificed. Isolated resection of the greater trochanter is rare; however, this completely disrupts the continuity of the AM and justifies reconstruction, often using a bone-tendon allograft. Proximal femur resection is the most common scenario. The extent of the trochanteric resection and the gluteal tendon attachments drives the type of prosthesis used. The two most used techniques consist in an allograft sleeve over a long cemented femoral stem (allograft prosthesis composite - APC) or a modular proximal femoral endoprosthesis (megaprosthesis) with a specific AM fixation system (small plate or wire cerclage, resorbable or metal wire, synthetic reattachment tube). These two techniques yield nearly identical long-term functional outcomes with complications specific to each: osteolysis and fracture for APC, failure of tendon reattachment for megaprosthesis. Beyond these technical considerations, one must consider the poor availability of massive bone allografts. This is a highly relevant issue in France, and partially explains the shift to reconstruction with a megaprosthesis. Lastly, we will look at the different clinical and diagnostic tests used to evaluate the function of the AM in an oncology context and the outcomes of the various types of reconstruction.

Ultrasound in Total Hip Replacement: Value of Anterior Acetabular Cup Visibility and Contact With the Iliopsoas Tendon.

OBJECTIVES: To assess visibility of the acetabular cup in total hip replacement and to determine the value of direct and indirect signs of iliopsoas impingement syndrome with ultrasound. METHODS: Ultrasound examinations were performed by a single operator in 17 patients with iliopsoas impingement syndrome and 48 control patients. Cup visibility, contact between the cup and psoas tendon, and the presence of indirect signs of iliopsoas impingement syndrome were investigated in all patients. When the acetabular cup was visible, its size and position in relation to the psoas tendon were recorded. RESULTS: Anterior cup visibility (P = .03), contact with the psoas tendon (P < .001), psoas tendinopathy (P = .02), and iliopsoas bursitis (P < .001) were significantly associated with iliopsoas impingement syndrome, the latter reported with specificity of 100%. In the sagittal plane at the level of the psoas tendon, a maximum sagittal length of greater than 5 mm and a posteroanterior cup shift of 3 mm or greater yielded respective sensitivities of 82% and 59% and specificities of 81% and 100%. CONCLUSIONS: When iliopsoas impingement syndrome is clinically suspected, the presence of iliopsoas bursitis or a posteroanterior cup shift of greater than 3 mm under the psoas tendon serve to confirm the diagnosis. In the absence of these conditions, a therapeutic test may be necessary because of the incomplete, albeit high, specificity of other signs.

Is tibial cut navigation alone sufficient in medial unicompartmental knee arthroplasty? Continuous series of fifty nine procedures.

PURPOSE: Our purpose was to assess medial unicompartmental knee arthroplasty with navigation alone for the tibial cut and limb alignment. We hypothesised that this technique could be used routinely in practice. METHODS: Outcome measures were tibial cut orientation and residual varus. Six-month post-operative radiographs of 59 knees were assessed. RESULTS: Tibial cut orientation was within 2° of planned in 70.2 and 76.3 % of knees in the coronal and sagittal planes, respectively (49.1 % in both), within 4° in 91.2 and 91.5 %, respectively (82.5 % in both). All coronal-plane errors were in varus. Excessive planed tibial slope was at risk of excessive varus of the tibial cut. The hip-knee-ankle angle was ≤179° in 81.4 % and the mechanical axis through Kennedy Zone 2 in 59.3 % of knees. Risk factors for inadequate varus were pre-operative hip-knee-ankle angle >176° and strictly articular varus. CONCLUSIONS: Our results are not as good as previously reported with this technique, but taking into account the factors of failure identified, we could enhance the results.

Arthroscopic Measurement of Cartilage Lesions of the Knee Condyle: Principles and Experimental Validation of a New Method.

PURPOSE: To present a new method of arthroscopic measurement of the surface and location of condylar lesions. METHODS: We propose measuring the height of the condylar lesion by using the lesion's arc (Δ°) obtained from the difference between the angle of flexion at the beginning of the lesion and the angle of flexion at the end of the lesion. The first goal of the study was to determine the intra and inter reliability of the lesion's arc. Experiment 1: 20 deep lesions were evaluated using the lesional arc by two arthroscopists. Experiment 2: In a second series of 20 lesions, the flexion angles of the knees were recorded using a goniometer. All 10 knees (5 in each series) were then disarticulated and the true lesion arc was checked with a goniometer to assess the validity of the scopic measurements. The second goal was to obtain the height of the lesion from the lesion's arc. The lesion arc Δ° of the condylar is converted into height (millimeters) on the basis of a table obtained from 5 standard profiles of the lateral X-ray of the knee. RESULTS: Experiment 1: The intra observer reliability was good but the inter observer reliability was poor. Experiment 2: The intra and inter observers' reliability were good. On the anatomic control after disarticulating the knee, the confidence interval was narrower when using the goniometer. CONCLUSIONS: We propose a simple, reliable method to measure the height of a condylar lesion with the lesion's arc during arthroscopy.

[Painful knee: choosing the right imaging test]. / Quelle imagerie devant un genou douloureux?

The diagnosis of non-traumatic knee complaints relies on history taking and clinical examination, joint fluid analysis and imaging tests. This paper aims at reminding the benefits of conventional radiography and clarifying the role of ultrasound and magnetic resonance imaging based on illustrated case reports.

Hip pain from impingement and dysplasia in patients aged 20-50 years. Workup and role for reconstruction.

In the 20-50-year age group, hip pain usually indicates dysplasia. Chronic mechanical pain is the usual pattern, although acute pain caused by avulsion or degeneration of the labrum may occur. The morphological characteristics of the dysplastic hip should be evaluated, and the link between the dysplasia and the osteoarthritis should be confirmed. Three factors indicate a favorable prognosis: joint space preservation, age younger than 40 years, and correctable femoral and acetabular abnormalities. Reconstruction is highly desirable, as it delays the need for joint replacement by 20 years. After 15 years, good outcomes are seen in 87% of patients after shelf arthroplasty and 85% after femoral varus osteotomy with or without shelf arthroplasty. Chiari acetabular osteotomy can be performed in patients with osteoarthritis but is followed by prolonged limping. Periacetabular osteotomy should be reserved for patients with moderate dysplasia and no evidence of osteoarthritis. Shelf arthroplasty and femoral osteotomy require 5-8 months off work (compared to 5 months after hip replacement surgery) but subsequently permits a far more active lifestyle. Hip replacement, which is required 20 years or more after biologic reconstruction, carries the same prognosis as first-line hip replacement (good results in 80% of patients after 15 years). Acute sharp pain related to anterior hip derangement also occurs in primary femoroacetabular impingement (FAI). The most common pattern is cam impingement, which is due to a decrease in head-neck offset and manifests as pain during flexion and adduction of the hip. Cam impingement can be corrected by anterolateral osteoplasty, which is often performed arthroscopically. Pincer-type impingement is contact between the anterior acetabular rim and the femoral neck due to retroversion of the proximal acetabulum. The imaging study strategy is discussed. Coxometry, computed tomography, and arthrography can be used. Primary FAI, which occurs as a result of geometric abnormalities, should be distinguished from secondary impingement. Causes of secondary impingement include exaggerated lumbar lordosis with pelvic tilt and to hip osteophytosis (sports or posterior hip osteoarthritis). Osteoplasty is rarely appropriate in patients with secondary impingement. The features of acute anterior hip derangement are now better defined. They can be used to guide palliative treatment, which is effective, in the medium term at least. Experience acquired over the last two decades has established the efficacy of surgery for hip dysplasia.

[Mini-invasive fixation of proximal femoral fractures: what benefit for elderly patients?]. / Ostéosynthèses mini vulnérantes du fémur proximal: quels enjeux pour les fractures du sujet agé ?

Fixation is used to treat more than two-thirds of proximal femur fractures. The mortality rate is about 25% at one year in these patients, who have an average age of about 80 years. This is mainly due to aging, but also to a gradual deterioration of general health (especially if the operation has been delayed, or after a long stay in the surgical ward) and to local complications (displacement, infection, hematoma). Two fixation devices (a sliding screw plate and a trochanteric nail) have been designed for mini-invasive treatment with fluoroscopic guidance and an incision smaller than 50 mm. The aim is to respect the soft tissues and thereby to avoid local complications, diminish pain, and facilitate early weight-bearing Hospital discharge is possible after 3 or 4 days. Laboratory experiments have shown the satisfactory resistance of the implant and bone at full weight bearing A preliminary series of 30 patients showed the feasibility of these techniques. Primary fusion was achieved in 27 cases. There were no infections and no bleeding, despite antiplatelet treatment. The techniques have now been optimized and multicenter studies are held to determine their real benefit. Fracture fusion and hip motion should be at least as good as with open surgery (90 to 96% fusions, albeit influenced by the precise position of the implants and by osteoporosis). Mortality may be slightly reduced, thanks to immediate operation, early discharge, and fewer local complications. The cost of treatment could also be significantly reduced by the shorter hospital stay. In a few years' time, mini-invasive treatment may become the standard for elderly patients with proximal femur fractures.

Can rotation osteotomy remain effective for more than ten years?

Trochanteric rotation osteotomies displace the necrotic zone of the femoral head outside the major acetabular weight-bearing zone and rotate the head anteriorly or posteriorly. Nineteen consecutive patients were selected for rotation osteotomy based on age,absence of progressive disease, and preoperative imaging studies predicting that rotation osteotomy would move the entire necrotic zone away from the acetabular roof. Factors associated with failure were head flattening and necrosis deeper than one third of the femoral head diameter. Among patient subsets with identical disease stages, outcomes seemed better after posterior rotation than after anterior rotation. Rotation osteotomies,fixed by a nail plate, can be recommended in a few selected patients with shallow necrosis involving less than one third of the femoral head diameter and without osteoarthritis or head flattening. Under these conditions, good outcomes may be achieved for 10 years or longer.