Failure of the femoral component after a primary or revision THA is commonly associated with some degree of femoral bone loss. Depending on the quantity and quality of the remaining host bone, femoral stem revision can be challenging.

Twenty patients with severe proximal femoral bone loss due to prosthetic loosening were treated by Wagner cementless self-locking revision stems with a mean follow up of 24 months (range 18–36 months). The indication of revision surgery was aseptic loosening in 16 patients and septic loosening in 4 cases.

At the end of the follow up the mean Harris hip score increased from 35 to 86 points. Definite radiographic evidence of bone regeneration in the bony defects was achieved within 3 months in all patients.

Implantation of a Wagner cementless selflocking revision stem provided satisfactory results. The Wagner SL Revision prosthesis, firmly and rotationally stable fixed in the medullary cavity of the healthy bone distal from the original prosthetic bed, with its conical longitudinal ribs and cementless anchorage, bridges the defective prosthetic bed and hereby leads to a condition of relative mechanical stability. With time, there is active ossification in the old prosthetic bed, replacing lost bone.

The femur begins to bow anteriorly at the 200 mm level, but may bow earlier in smaller people. If the stem to be used is less than 200 mm, a straight stem can be used. If the stem is longer than 200 mm, it will perforate the anterior femoral cortex. I know this because I did this on a few occasions more than 20 years ago. To use a long straight stem, there are two techniques. One can either do a diaphyseal osteotomy or one can do a Wagner split (extended trochanteric osteotomy). Both of these will put the knee in some degree of hyperextension, probably insignificant in the elderly, but it may be of significance in the young. In very young people, therefore, it may be preferable to use a bowed stem to avoid this degree of recurvatum. There are two different concepts of loading. Diaphyseal osteotomy implies a proximal loading has been sought. The Wagner split ignores the proximal femur and seeks conical fixation in the diaphysis. There will be very little bone-bone contact between what remains of the attached femur and the detached anterior cortex so that it is important to ensure that the blood supply to the anterior cortex remains intact, preferably by using Wagner's technique, using a quarter-inch osteotome inserted through the vastus to crack the medial cortex. Current modularity is of two types. Distal modularity was attempted many years ago and was never successful. Proximal modularity, as for example, the S-ROM stem, implies various sizes of sleeves fit onto the stem to get a proximal canal fill. In mid-stem modularity, the distal stem wedges into the cone. It has to be driven into where it jams and this can be somewhat unpredictable. For this reason, the solid Wagner stem has been replaced by the mid-stem modular. Once the distal femur is solidly embedded, the proximal body is then selected for height and version. The proximal body is unsupported in the mid-stem modular and initially, few fractures were noted at the taper junction. Cold rolling, shot peening and taper strengthening seem to have solved these problems. There are a variety of types of osteotomy, which can be used for different deformities. With a mid-stem modular system, generally, all that needs to be done is a Wagner-type split and fixation is sought in the mid-diaphysis by conical reaming. No matter what stem is used, distal stability is necessary. This is achieved by flutes, which engage the endosteal cortex. The flutes alone must have sufficient rotational stability to overcome the service loads on the hip of 22 Nm. I divide revision into three categories. In type one, the isthmus is intact, i.e. the bone below the lesser trochanter so that a primary stem can be used. In type two, the isthmus is damaged, i.e. the bone below the lesser trochanter, so a long revision stem is required. In a type three, there is more than 70 mm of missing proximal femur. The Wagner stem may be able to handle this on its own, but most other stems are better supported with a structural allograft cemented to the stem. The reported long term results of mid-stem modular revision implants are good as in most, over 90% survivorship. The introduction of modularity appears to have overcome initial disadvantage of the Wagner stem, i.e. its unpredictability in terms of leg length

Introduction. There have been increased concerns with trunnion fretting and corrosion and adverse local tissue reactions (ALTR) in total hip arthroplasty. We report on 11 catastrophic trunnion failures associated with severe ALTR requiring urgent revision arthroplasty. Methods. We retrospectively reviewed 10 patients with gross trunnion failure (n=11) and an additional 3 patients with impending trunnion failure. Results. All patients presented to the emergency department with severe pain, an inability to bear weight, and dramatic radiographs demonstrating implant failure. Patients were an average of 7.8 years from the initial index procedure. Implants were a cementless component with metal on polyethylene bearing from a single manufacturer with a 36mm femoral head size and a range of extended offset of 2.5 to 5.5 and neck length of +0 (n=1), +5 (n=5), and +10 (n=5). The implant was used during a limited time (2.5 years) by single surgeon in our practice using a posterior approach, with the last implant placed 7 years ago. Prior to revision, serum cobalt levels were elevated, typically more than chromium levels. Radiographs demonstrated failure of the implant with a dissociation of the head from the taper and large radiolucent fluid collections from the metal debris (Fig 1). Intraoperative findings and magnetic resonance imaging confirmed a diagnosis of ALTR with loss of abductors, and severe material loss from the taper (Fig 2). We estimate a conservative incidence of catastrophic trunnion failure in our series to be 2.2% (n = 636 total implanted). A femoral revision with a modular Wagner stem was performed, and when necessary the acetabulum was revised secondary to destruction of the locking mechanism from mechanical wear. Discussion and Conclusion. ALTR can occur in patients with catastrophic failure of their trunnion. Radiographs are dramatic. Serum metal ion levels and magnetic resonance imaging is comparable to adverse local tissue reaction in metal on metal bearing surfaces, corrosion at the head neck taper, and corrosion of dual modular taper stems. The initiating events leading to this mechanism of trunnion failure is unknown. We observed trunnion failure at large head sizes and at increased femoral head offsets. Other groups have reported an association of trunnion failure at increased neck length and head size with a variety of manufacturers. Based on our experience, we have been able to identify impending failure based on subtle radiographic criteria and elevated metal ion levels. A failure rate of 2% at 7.8 years is non-trivial. Impending trunnion failure should be considered as a possible diagnosis in a painful total hip arthroplasty with unknown etiology. Serum metal ion levels and magnetic resonance imaging should be obtained as part of the initial evaluation

To report mid-term results of PJI treated with uncemented stems. : 80 hips of PJI after THA were treated with uncemented stems from 01/1993 to 12/2012 and followed prospectively. Selection occurred for one- (n=27) or two-stage (n=53) exchange according to the Liestal algorithm. Surgical approaches were transfemoral (n=58), transgluteal (n=9) or transtrochanteric (n=13). A monoblock (Wagner SL, n=58) or modular (Revitan, n=22) revision stem was implanted. On the acetabular side 44 Müller rings, 33 Burch-Schneider cages (combined with a cemented PE-cup) and 3 press-fit cups were used. Kaplan-Meier survival was calculated for endpoints (a) persistence of infection, (b) septic/aseptic stem loosening. Radiographs were analysed for (a) subsidence, (b) distal stem integration, (c) changes in cortical thickness, (d) proximal femur restoration, (e) radiolucency around stem/cup. Mean FU was 5.2 (2–15) years. PJI was eradicated in 77 of 80 hips (96%). 3 patients (all two-stage) had a treatment failure. 2 were treated successfully with an additional two-stage exchange. In the 3rd patient we were not able to control infection and exarticulation was performed. Furthermore, one stem was revised for aseptic loosening (5 years), 1 for a broken Wagner stem (7 years) and 1 for subsidence (8 months). Stem survival after 5 years was 93% (SD ±2.5 years). 2 cups were revised for aseptic loosening and 1 for recurrent dislocations. Subsidence ≥5mm was found in 6 hips and occurred always within 3 months after surgery independent of stem type (p=0.947) and approach (p=0.691). Proximal femoral remodelling after transfemoral approach was excellent or good in 71% (32 excellent, 9 good) with no difference between one-/two-stage exchanges (p=0.288). Initial distal stem integration was 65mm medial and 66mm lateral and increased to 8mm medial (p=0.716) and 10mm lateral (p<0.001). Cortical thickness was unchanged over the entire FU period (p=0.493). Radiolucencies were seen around 26 stems, only the stem revised after 5years was rated loose. Eradication of PJI was high using our established protocol even with uncemented revision stems. Mid-term survival was independent from one-/two-stage revision and comparable to results for aseptic loosening revision

There is no mathematical relationship between the internal diameter of the femoral metaphysis and diaphysis. Unless an infinite number of monolithic stems are available with variable metaphyseal and diaphyseal diameters, which is not economically possible, even in virgin cases, the surgeon has to decide if the stem is going to fit in the metaphysis or the diaphysis. It is not possible to match both. In revision cases with a hollowed out metaphysis, the situation is much worse. As it is obviously easier to fit the diaphysis, this is what stems such as the AML and Wagner stem have done. They completely ignore the metaphysis and obtain fixation in the diaphysis. This is all well and good, but it means that the proximal femur is unloaded, like an astronaut in space. While, there will be some recovery due to removal of the toxins and local muscle pull, it will be incomplete. Furthermore, should sepsis occur, one is faced with the horror of removing a distally fixed implant. Clearly, if proximal fixation, i.e. above the level of lesser trochanter could reliably be achieved, this would be preferable in terms of proximal loading leading to bone recovery and ease of removal should it be required. The only way that proximal loading can be achieved is if the metaphyseal and diaphyseal parts of the component can be varied infinitely. This clearly can only be achieved by using a modular stem. The concern with modularity always has been fretting at the sleeve-stem locking mechanism with release of metal ions. The stem, which I have been using for the last 25 years, is the SROM stem. Fretting and ion release had never been an issue. As the components are made of a relatively soft titanium alloy, it is likely that the sleeve and the stem cold weld, thus, eliminating any movement and eliminating friction. I have a follow-up of roughly 120 revision cases with a minimum follow-up of 5 years and a maximum follow-up of 22 years. I have no loosening in easy revision cases where a primary stem was used. I have had some loosenings in extremely difficult revision situations where a long bowed stem was required, but even then, the loosening rate is less than 3%. I use this stem in primary situations, i.e. in about 80% of all the primaries I have done. This means I have done roughly 1500 cases or more. Other than some late infections, I have never, ever had any stem loosening in a simple case. Obviously, I have had loosenings in some cases, where we have been doing fancy shortening or de-rotation osteotomies, but none in simple primary cases. I would, therefore, suggest that the surgeon, if he wishes to use this stem, please try it out on some simple primary cases. The ability to vary distal and proximal internal diameters and proximal geometry makes for easy surgery. I have been using this stem for 25 years and continue to use it in all my primary noncemented cases. I believe in the adage of “train hard and fight easy.” I think that surgeons should not get themselves into a situation where they are forced in a difficult case to use something they have never seen before

Aim. To assess the survivorship of a tapered fluted Titanium monoblock stem in conjunction with subtrochanteric shortening for patients with High Dislocation performed at 2 centres. Methods. This was a retrospective study of 84 hips in 52 patients between two centres. All patients had a high dislocation. Thirty five patients had bilateral dysplasia. All patients had total hip arthroplasty with a subtrochanteric shortening osteotomy. The acetabular component was placed at the level of the anatomic hip centre. The femoral component was the “Wagner Cone prosthesis” which is a monoblock Titnium Alloy stem, tapered and fluted. The acetabular component varied. All patients had a follow up examination with a Harris Hip Score and a plain radiograph. The radiographs were assessed for osteotomy complications, change in stem position, evidence of loosening, heterotopic ossification & stress shielding if any. Notes were reviewed for complications. Results. The mean age at operation was 55 yrs (range 20–83). The mean follow up was 9 years (range3–20). Eight patients were lost to follow up (16%). All the rest of the femoral components survived that were available for follow up −84% (worst case scenario). Six patients (7.8%) had an early complication that needed a reoperation. The Mean Harris Hip Score (HHS) improved from 42 points to 88 points. Conclusion. The success rate of patients undergoing Cementless Arthroplasty using the Wagner cone stem in conjunction with a subtrochanteric shortening osteotomy is very high. The complication rate is however larger than in the normal population

Laxity Differences in CR & PS TKA -Achieving Total Knee Balancing Using Bone Cut Adjustments and Correlation with Varus-Valgus Lift-Off. The Incidence and Mid Term Functional Effect of Partial PCL Recession in Fixed and Mobile Bearing PCL Retaining TKA. Clinical and Radiographic Results of a Modern Design, Onlay Patellofemoral Arthroplasty at a Minimum Two-Year Follow-Up. Custom Cutting Guides Do Not Improve Total Knee Arthroplasty Outcomes at 2 Years Follow-up. Tourniquet Use During TKA -Effect on Recovery of Strength and Function: a randomised, double-blind, control trial. Prospective, Randomised Trial of Standard vs Cross-linked Tibial Poly. Crosslink vs. Conventional TKA Poly Retrieval Analysis. Unplanned Readmissions after TKA Using a Statewide Database. Does Prior Cartilage Restoration Negatively Impact Outcomes of TKA. Periprosthetic Femur Fracture: Better to Revise than to Fix. Increased Non-stemmed Tibial Failures in Patients with a BMI ≥ 35. The Effect Of Canal Fit And Fill in Revision THA With Modular, Fluted, Tapered Stems. The Wagner Cone Stem For The Challenging Femur In Primary Total. Will Metal Heads Restore Integrity of Corroded Trunnions at Revision THR?. Influence of Head Size, Materials and Taper Design on Fretting and Corrosion of Metal on Polyethylene THR. Delta Ceramic on Ceramic THA – Midterm IDE Study Results. Refining Acetabular Safe Zone for Posterior Approach in THA. Comparison of a Pain Program for THA with and without Liposome Bupivacaine

Modularity in femoral revision evolved to address the specific weaknesses in the execution and results of the early Wagner SL stem, namely dislocations and subsidence. With modularity, distal canal fit can be achieved independently, and the proximal geometry can be created to re-establish the leg length and offset. The benefits of modularity relate specifically to being able to modify a plan intra-operatively based on the conditions that are encountered in mid battle. Inherent in this concept is the principle of predictability. The extent to which the conditions of operation may change requires alternatives to manage those changes. More importantly we need to be able to predict how an implant will sit in the bone. At the inception and with subsequent manifestations of modular fluted stems, our ability to predict where the final implant will seat based on the trial options that existed was poor. For this reason, some modular stem designs offered no trial. This was part of the imperative for modularity, so that if the implant set too high it could be easily removed with reaming a little deeper and put back in. If the stem sat more deeply than had been anticipated, the change could be compensated by an alteration in the proximal modular segment. Reproducible mid- to long-term results have been published with this type of stem. Potential negatives of the modular junction include stem breakage, fretting and corrosion, cost, and the need to accommodate a large sized proximal segment within the proximal femur. The most important feature in modern non-modular implants will be predictability. We need to be able to predict that the final reamer will sit at a particular level in the femoral bone, and the trial will reproduce this level, and the final implant will reproduce this level. More importantly, we need to be able to predict that implants will remain where they are put, and not subside. Subsidence has been causally associated with implant under-sizing, which is an error in surgical execution. As such, design features that optimise the ability to achieve intimate and broad endosteal contact between the implant and the bone can help reduce subsidence. These include precise, sharp reamers, implants in 1 mm increments, and trials that reproduce the position of the final implant. A larger implant is less likely to break, and we recommend preparation for the largest implant that the diaphysis can accommodate, often evident in the tactile feedback from the reamer, and the quality of the reamed bone being removed. Reaming is performed eccentrically in the proximal femur, so as to engage the diaphysis optimally. The need for a kink in the stem is important for modular stems, which have bulky proximal segments that can create conflict with the peritrochanteric bone in smaller patients. Non-modular stems can have a smaller proximal diameter, such that a straight stem can be accommodated in most revision cases. Early follow-up of a modern non-modular stem has shown excellent clinical improvement and reproducible ingrowth. Subsidence of > 10 mm occurred in 6 hips (6%), which is a notable improvement in historical values for this stem type, but remain short of some reports with modular stems. Improvements in goals and techniques of reaming and implantation are surely part of the improvements that have been documented, as well as those yet to be realised. Predictability will lead to simplicity and intuitiveness