Introduction. Objective was to assess clinical results of treatment of Infected Non Union (INU) of long bones, using Antibiotic Cement Impregnated Nail (ACIN), a single or two staged approach, Stage 1 - Debridement, eradication of infection, primary stabilization with (ACIN). 2nd Stage - Definitive stabilization and early rehabilitation. Methods. 185 cases of infected non-union of long bones from Jan 2002 to Jan 2009 were treated in this hospital. 46 females and 139 males, age varied from 17–65 years (Avg. 40). Tibia was the commonest bone to be affected, followed by femur & humerus. The control of infection was by debridement, antibiotic cement impregnated K-nail (ACIN) insertion with or without Ilizarov ring fixator application, second stage treatment by definitive internal fixation and bone grafting was done if required. Average duration of follow up, was 26 months (14–58 months). Main outcome measurements were assessment of bone healing, functional outcome, healing time and complications. Results. Out of the 185 cases treated in our institute 174 (93.7%) patients achieved union at an average of 8 months. 2 limbs with non union tibia fractures were amputed on demand by patients, 2 limbs developed severe edema, 7 patients did not achieve union, inspite of repeated procedures. Infection was controlled early especially in Type 1 non unions. 5 patients had persistent infection though mild inspite of 2 or 3 surgeries of exploration and curettage. Discussion and conclusion. The two staged procedure described gives satisfactory results. Antibiotic and cement impregnated nails and beads achieve good infection control without any complications and reduce the healing time. Ilizarov fixator helps in stabilization, compression, deformity correction at the same time and plays a significant role in the path to union. Fixator should be removed as early as possible to avoid restriction of movements

Introduction. The Rotational alignment is an important factor for survival total knee Arthroplasty. Rotational malalignment causes knee pain, global instability, and wear of the polyethylene inlay. Also, the anterior cortex line was reported that more reliable and more easily identifiable landmark for correct tibial component alignment. The aims of the current study is to identify effect of inserting the tibial baseplate of using anterior cortex line landmark of TKA on stress/strain distributions within cortical bone and bone cement. Through the current study, final aim is to suggest an alternative position of tibia baseplate for reduction of TKA failures with surgical convenience. Materials and Method. A three-dimensional tibia FE model with TKA was generated based on a traditional TKA surgical guideline. Here, a commercialized TKA (LOSPA, Corentc, Korea) was considered corresponded to a patient specific tibia morphology. Tibia baseplate was positioned at anterior cortex line. Alternative two positions were also considered based on tibia tuberosity 1/3 line and tibia tuberosity end line known as a gold standard (Fig. 1-A). Loading and boundary conditions for the FE analysis were determined based on five activities of daily life of persons with TKA (Fig. 1-B). FE model was additionally validated comparing with an actual mechanical test. Results and Discussions. The, through comparing with strain distribution on the cortical bone measured from the actual mechanical test considering 0°, 30° 60°, 90°, 120° and 140° flexion with femoral rollback phenomenon (Fig. 2). Stress/strain on the cortical bone (medial region) of the proximal tibia for the baseplate positioned at anterior cortex line were a little better distributed than those at tibia tuberosity 1/3 line and tibia tuberosity end line although the stress/stain values were similar to each other (Fig. 3-A). Potential fracture risk of the bone cement for the baseplate positioned at anterior cortex line was lower than that at tibia tuberosity 1/3 line and tibia tuberosity end line, considering safety factor (N=3). Particularly, Potential fracture risk of the bone cement for the baseplate positioned at tibia tuberosity 1/3 line known as a gold standard was highest (over 20MPa for stair down activity) (Fig. 3-B). Conclusion. Our results suggested that anterior cortex line landmark was feasible to apply positioning method on the tibial baseplate in terms of mechanical characteristics which were compared to tibia tuberosity 1/3 line and tibia tuberosity end line known as a gold standard. This study may be valuable by suggesting for the first time an alternative baseplate position for reduction of TKA failures with surgical convenience

This study aimed to analyze the effect of two different techniques of cement application: cement on bone surface (CoB) versus cement on bone surface and implant surface (CoBaI) on the short-term effect of radiolucent lines (RLL) in primary fully cemented total knee arthroplasties (TKA) with patella resurfacing. 379 fully cemented TKAs (318 patients) were included in this monocentric study. Preoperative and postoperative at week 4 and 12 month after surgery all patients had a clinical and radiological examination and were administered the Oxford Knee Score (OKS). Cement was applied in two different ways among the two study groups: cement on bone surface (CoB group) or cement on bone surface and implant surface (CoBaI group). The evaluation of the presence of RLL or osteolysis was done as previously described using the updated Knee Society Radiographic Evaluation System. The mean OKS and range of motion improved significantly in both groups at the 4-week and 12-month follow-up, with no significant difference between the groups (CoB vs. CoBaI). RLL were present in 4.7% in the whole study population and were significantly higher in the CoBaI group (10.5%) at the 4-week follow-up. At the 12-month follow-up RLL were seen in 29.8% of the TKAs in the CoBaI group, whereas the incidence was lower in the CoB group (24.0% (n.s.)). There were two revisions in each group. None of these due to aseptic loosening. Our study indicated that the application of bone cement on bone surface only might be more beneficial than onto the bone surface and onto the implant surface as well in respect to the short-term presence of RLL in fully cemented primary TKA. The long-term results will be of interest, especially in respect to aseptic loosening and might guide future directions of bone cement applications in TKA

A common location for radius fracture is the proximal radial head. With the arm in neutral position, the fracture usually happens in the anterolateral quadrant (Lacheta et al., 2019). If traditional surgeries are not enough to induce bone stabilization and vascularization, or the fracture can be defined grade III or grade IV (Mason classification), a radial head prosthesis can be the optimal compromise between bone saving and recovering the “terrible triad”. A commercially available design of radial head prosthesis such as Antea (Adler Ortho, Milan, Italy) is characterized by flexibility in selecting the best matching size for patients and induced osteointegration thanks to the Ti-Por. ®. radial stem realized by 3D printing with laser technique (Figure 1). As demonstrated, Ti-Por. ®. push-out resistance increased 45% between 8 −12 weeks after implantation, hence confirming the ideal bone-osteointegration. Additional features of Antea are: bipolarity, modularity, TiN coating, radiolucency, hypoallergenic, 10° self-aligning. The osteointegration is of paramount importance for radius, in fact the literature is unfortunately reporting several clinical cases for which the fracture of the prosthesis happened after bone-resorption. Even if related to an uncommon activity, the combination of mechanical resistance provided by the prosthesis and the stabilization due to the osteointegration should cover also accidental movements. Based upon Lacheta et al. (2019), after axial compression-load until radii failure, all native specimens survived a compression-load of 500N, while the failure happened for a mean compression force of 2560N. The aim of this research study was to test the mechanical resistance of a radial head prosthesis obtained by 3D printing. In detail, a finite element analysis (FEA) was used to understand the mechanical resistance of the core of the prosthesis and the potential bone fracture induced in the radius with simulated bone- resorption (Figure 2a). The critical level was estimated at the height for which the thickness of the core is the minimum (Figure 2b). Considered boundary conditions:. - Full-length prosthesis plus radius out of the cement block equal to 60mm (Figure 2a);. - Bone inside the cement equal to 60mm (Figure 2b);. - Load inclined 10° epiphysiary component (Figure 2c);. - Radius with physiological or osteoporotic bone conditions;. - Load (concentrated in the sphere simulating full transmission from the articulation) of 500N or 1300N or 2560N. Figure 3 shows the results in terms of maximum stress on the core of the prosthesis and the risk of fracture (Schileo et al., 2008). According to the obtained results, the radial head prosthesis shows promising mechanical resistance despite of the simulated bone-resorption for all applied loads except for 2560N. The estimated mechanical limit for the material in use is 200MPa. The risk of fracture is in agreement with the experimental findings (Lacheta et al. (2019)), in fact bone starts to fail for the minimum reported failure load, but only for osteoporotic conditions. The presented FEA aimed at investigating the behavior of a femoral head prostheses made by 3D printing with simulated bone-resorption. The prosthesis shows to be a skilled solution even during accidental loads. For any figures or tables, please contact the authors directly

The first rule in properly cementing a femoral component is obtaining adequate exposure of the proximal femur. This is achieved reproducibly in anterior approach surgery with anterior and superior capsulotomy, combined with release of the conjoined tendon from the inner trochanter and piriformis tendon retraction, or flip behind the trochanter. This will be demonstrated. The steps of cementation are well established, and not specific to one approach. They involve entry to the proximal femur in a lateral and posterior position, achieving central alignment within the proximal femur with the broach, application of a cement restrictor to a point 1.5 to 2cm distal to the proposed tip of the implant, appropriate preparation of the cancellous bone to receive the cement, applying cement in a sufficiently doughy state to be able to achieve penetration into the cancellous bone, and mechanical pressurization into that cancellous bone. We routinely apply cement directly to the proximal aspect of the femoral component as the cement sticks to the metal, preventing marrow contents generated during the insertion from contacting the metal. In discussing the factors contributing to a dry surgical field, the importance of relative hypotension achieved from regional anesthesia cannot be overstated

In North America, cementless femoral replacement has all but replaced cementing and cement technique is at risk for becoming a lost art. Published results of cemented femoral components with a well-designed femoral component and good surgical technique are excellent and equivalent to cementless technology. With an increasing focus on cost as part of value-based care, consideration for returning to cement for a select population is appropriate. Furthermore, there are patient populations that may benefit from a cemented femur with registries demonstrating superior short term outcomes. These include the elderly and patients with osteoporotic femurs. The goal of femoral cementing is to maximise the interdigitation of bone cement with metaphyseal trabecular bone and the irregular surface of the endosteum while at the same time minimizing the risk of embolization. The steps for femoral cementing include:cFemoral broaching – understand the relationship between the broach and stem as it relates to cement mantle thickness; Canal preparation; Gentle curetting to remove loose cancellous bone; Pressurised lavage to remove fat and marrow elements – this decreases the risk of embolization and enhances the strength of the bone-cement interface; Dry the canal – suction, adrenaline soaked sponge – this minimises bleeding and enhances the strength of the bone cement interface; Cement preparation – vacuum mix or centrifuge the bone cement – this minimise large voids that weaken the bone cement; Cement insertion – insert in a retrograde fashion and pressurise the cement – this optimises the cement column and the bone cement interface; Stem insertion – insert slowly with a system that centralises the stem – this prevents mantle defects that have been associated with stem loosening

INTRODUCTION. Experience with Metal on Metal (MoM) hip resurfacing devices has shown adequate cementation of the femoral head is critical for implant survival. Bone necrosis can be caused by the temperature change in the peri-prosthetic bone whilst the cement cures during implantation. This can lead to implant loosening, head/neck fracture and implant failure. During the implantation it is known that implants change shape potentially altering joint clearance and causing loosening. Given the history of Metal on Metal implant failure due adverse tissue reactions from Cobalt and Chromium particles we sought to test a novel Ceramic on Ceramic (CoC) bearing which may mitigate such problems. AIM. We set out to compare the behaviour of a novel ceramic femoral head component to a standard metal component in a hip resurfacing system after cemented implantation in a physiological warmed cadaveric model. Our first aim was to perform heat transfer analysis: To document time to, and extent of, maximum temperature change on the metal/ceramic surface and inside the resurfaced femoral head bone. Our second aim was to perform a dimensional analysis: To document any resulting deformation in the metal/ceramic femoral head bearing diameter during cementation. METHODS. Femurs were removed from four fresh frozen cadavers and placed into a vice. One surgeon with extensive experience in hip resurfacing surgery (JH) prepared all the femoral heads for implantation. Cadaveric warming was performed using a thermostatic silicone heating element to achieve near physiological conditions (28–32°C). The femur components were then implanted onto the femur head using Simplex P (Stryker) low viscosity bone cement. We used four ceramic (ReCerf™) and four metal implants (ADEPT®) of equal and varying size. (2 × (42mm, 46mm, 48mm, 50mm). Temperature change was measured using a thermometer probe placed into femur neck and head from the lateral side with position check using an image intensifier. Implant surface temperature was measured using a calibrated infrared thermometer at a standard 30cm distance. Head bearing surface diameter was measured using a micro-meter. Measurements were taken 2mins pre-implantation and sequentially at 1, 5, 10, 15, 20, 25 and 30 minutes after implantation. RESULTS. The bone temperature change for both metal and ceramic implants fell after implantation and then increased. The implant surface temperature increased and then stabilised for both implants. There was no significant difference in the bone or surface temperature change between metal and ceramic implants. The bearing surface diameter change was greater in the metal implants, although this was not significant. All implants returned to within one µm of initial surface diameter at 30 minutes. CONCLUSIONS. The femoral head component of a ceramic resurfacing has similar properties for surface temperature change following implantation to conventional MOM resurfacing. The periprosthetic bone is not at risk of significant heat necrosis during cementation (max temp 32°C). The deformation following implantation was similar for both metal and ceramic components. All implants returned to near initial diameter. The deformation and temperature changes following implantation of a ceramic resurfacing are similar to a metal implant

The spine is a common site of metastasis. Complications include pathologic fracture, spinal cord compression, and neurological deficits. Vertebroplasty (VP) and Balloon Kyphoplasty (KP) are minimally invasive stabilization procedures used as a palliative treatment to improve mechanical stability, quality of life, and reduce pain. Photodynamic therapy (PDT) is a tumour-ablative modality that may complement mechanical stability afforded by VP/KP. This first-in-human study evaluates PDT safety when applied in conjunction with VP/KP. This dose escalation trial involved one light only control group and four light-drug doses (50,100,150,200J;n=6) delivered at 150mW from a 690nm diode laser by 800-micron optical fibers prior to KP/VP. Patients eligible for VP/KP in treating pathologic fracture or at-risk lesions at a single level were recruited. Exclusion criteria included spinal canal compromise or neurologic impairment. PDT is a two-step binary therapy of systemic drug followed by intravertebral light activation. Light was applied via bone trochar prior to cementation. This study used a benzoporphyrin derivative monoacid (BPD-MA), Verteporfin (VisudyneTm), as the photosensitizer drug in the therapy. Drug/light safety, neurologic safety, generic (SF-36), and disease-specific outcomes (VAS, EORTC-QLQ-BM22, EORTC-QLQ-C15-PAL) were recorded through six weeks. Phototoxicity and the side effects of the BPD-MA were also examined following PDT use. Thirty (10 male, 20 female) patients were treated (13 KP, 17 VP). The average age was 61 and significantly different between genders (Male 70yrs vs. Female 57yrs: p 0.05), and tumour status (lytic vs. mixed blastic/lytic: p>0.05). In most cases, fluence rates were similar throughout PDT treatment time, indicating a relatively stable treatment. Twelve (40%) of patients experienced complications during the study, none of which were attributed to PDT therapy. This included two kyphoplasty failures due to progression of disease, one case of shingles, one ankle fracture, one prominent suture, one case of constipation due to a lung lesion, one case of fatigue, and five patients experienced pain that was surgically related or preceded therapy. Vertebral PDT appears safe from pharmaceutical and neurologic perspectives. KP/VP failure rate is broadly in line with reported values and PDT did not compromise efficacy. The 50J group demonstrated an improved response. Ongoing study determining safe dose range and subsequent efficacy studies are necessary

The method of choice in the management of chronic infections is the exchange arthroplasty. The exchange arthroplasty can be performed either in a one- or in a two-stage setting, whereas the two-stage exchange arthroplasty is still considered the “gold standard” worldwide. The current literature and guidelines for PJI treatment deliver no clear evidence that a two-stage exchange procedure has a clearly higher success rate than the one-stage procedure. Since the first implantation of mixing antibiotics into bone cement in 1970s, the ENDO-Klinik followed until today in over 85% of all infected cases the one-stage exchange arthroplasty for the management of PJI. The main requirement is the known germ with known susceptibility based on microbiological diagnostics. Proper bone stock for cemented, in some cases, uncemented reconstruction, and the possibility of primary wound closure are also clear assumptions. The one-stage exchange arthroplasty delivers diverse advantages. For instance, the need for only one operation, shorter hospitalization, reduced systemic antibiotics and lower overall cost. A well-defined pre-operative planning regime is absolutely mandatory

Lavage and preparation of the cancellous bony surface can facilitate adequate fixation of components in cemented total knee arthroplasty (TKA). Commonly used techniques for bone preparation such as pulse lavage, apart from adding to the cost, may cause local loss of loose cancellous bone and may even drive contaminants deeper into the tissue when used during TKA. We describe a simple, inexpensive and effective tool of using a sterilised toothbrush for preparing bone surface during cemented TKA. This must be followed by adequate pressurization of cement at the right time to achieve close interdigitation of cement with trabecular bone

Introduction. Acetabular component loosening has been one of the factors of revision of total hip arthroplasty (THA). Inadequate mechanical fixation or load transfer may contribute to this loosening process. Several reports showed the load transfer in the acetabulum by metal components. However, there is no report about the influence of the joint surface on the load transfer. We developed a novel acetabular cross-linked polyethylene (CLPE) liner with graft biocompatible phospholipid polymer(MPC) on the surface. The MPC polymer surface had high lubricity and low friction. We hypothesized the acetabular component with MPC polymer surface (MPC-CLPE) may reduce load transfer in the acetabulum compared to that of the by CLPE acetabular component without MPC. Methods. We fixed the three cement cup with MPC-CLPE (Group M; sample No.1–3) and three cement cup with CLPE (Group C; sample No.4–6) placed in the synthetic bone block with bone cement with a 0.10mm thick arc-shaped piezoresistive force sensor, which can measure the dynamic load transfer(Tekscan K-scan 4400; Boston). (Fig 1) A hip simulator (MTS Systems Corp., Eden Prairie, MN) was used for the load transfer test performed according to the ISO Standard 14242-1. Both groups had same inner and outer diameter s of 28 and 50mm, respectively. A Co–Cr alloy femoral head with a diameter of 28 mm (K-MAXs HH-02; KYOCERA Medical Corp.) was used as the femoral component. A biaxial rocking motion was applied to the head/cup interface via an offset bearing assembly with an inclined angle of +20. Both the loading and motion were synchronized at 1 Hz. According to the double-peaked Paul-type physiologic hip load, the applied peak loads were 1793 and 2744 N described in a previous study. The simulator was run 3 cycles. We recorded both the peak of the contact force and the accumulation of the six times load in total. Secondly, we calculated the mean change of the load transfer. We used the Student t-test. P value < 0.05 was used to determine statistical significance. We used EZR for statistical analysis. Results. The mean of total accumulation of the load transfer in the group M is significantly lower than that of in the group C. (7037±508 N vs 11019±1290 N, P<0.0001). The peak of load in the group M was also significantly lower than that in the group C. (1024±166 N vs 1557±395 N) (Fig 2)The mean of the change of the load transfer in the group M is significantly lower than that of in the group C. (2913±112 N vs 4182±306 N) (Fig 3). Conclusion. The acetabular component with MPC surface could reduce and prevent the radical load transfer change toward to the acetabulum compared to CLPE acetabular component without MPC. For any figures or tables, please contact the authors directly

INTRODUCTION. We have conducted interface bioactive bone cement method (IBBC) in total hip arthoplasty (THA) to prevent generation of connective tissue and osteolysis for the longevity of cemented THA since 1985, in which non-resorbable crystalline osteoconductive hydroxyapatite (HA) granules were interposed on the interface between bone and bone cement. To prevent the patients from infection, we use HA granules impregnated with antibiotics. However, there have been no reports on the loading and release of antibiotics from fine granules of HA. Here, we have investigated the loading of antibiotics on HA and their release in vitro. MATERIALS AND METHODS. HA was impregnated with antibiotics such as flomoxef sodium (F), vancomycin hydrochloride (V) cefotiam dihydrochloride (C) and cefozopran hydrochloride (CE) under normal or reduced pressure. After washing with PBS three times, HA loaded with the antibiotic was placed in PBS. An aliquot of solution was sampled at appropriate time intervals and the amount of the released antibiotic was estimated based on the anti-bacterial activity. RESULTS AND DISCUSSION. When drug loading was done by dropping antibiotic solution to HA granules, the amount of antibiotic released from 20 mg of HA was 16 μg for F, 0 μg for V, 13 μg for C and 65 μg for CE. The release of F continued for 48 hrs and that of V and CEcompleted within 24 hrs. On the other hand, when antibiotics loading were conducted under reduced pressure, the amount of released antibiotic was 14 μg for F, 0 μg for V, 0 μg for C and 1670 μg for CE. The burst release was observed for CE and F, and the release of them completed in 24 hrs. Then, the release of C and CE was observed in 0.025 M EDTA solution after the antibiotic was loaded under pressure. Observation was done for 19 days, at which one third of HA was dissolved. After 40 μg of burst release, the release of C continued for 19 days, at which the total amount of C released was 122 μg. Meanwhile, the release of CE continued over 19 days, during which 3350μg of CE was released after the burst release of 3280 μg. Thus, CE seemed the most suitable antibiotic for our purpose. The burst release of CE absorbed in HA following the issue of CE surrounding the HA granules on the interface of bone and bone cement is very effective for the protection of early infection after joint replacement

The major benefit of TKA with tourniquet is operating in a bloodless field. A possible secondary benefit is a better cement-bone interface for fixation. The disadvantages of tourniquet use for TKA include multiple risk factors both local and systemic: Nerve damage, Altered hemodynamics with limb exsanguinations (15–20% increase in circulatory volume) and reactive hyperemia with tourniquet release (10% increase in limb size increasing soft tissue tension and secondary pain), Delay in recovery of muscle function, Increased risk of DVT with direct trauma to vessel walls and increased levels of thrombin-antithrombin complexes, A 5.3x greater risk for large venous emboli propagation and transesophageal echogenic particles, Vascular injury with higher risk in atherosclerotic, calcified arteries, Increase in wound healing disturbances, Obese patients TKA with tourniquet show impaired endothelial function and more DVTs. Our initial experience with TKA without tourniquet was in high risk patients with previous DVT or PE, multiple scarring, or compromised cardiovascular status. We have used this method on all patients for the last 14 years. The protocol includes regional anesthesia, incision and approach made with 90-degree knee flexion, meticulous hemostasis, jet lavage and filtered carbon dioxide delivered to dry and prepare bone beds for cementation, application of topical tranexamic acid and routine closure. We have encountered no differences in blood loss or transfusion rates, cement penetration/ fixation, less postoperative pain, faster straight leg raise and knee flexion gains, and fewer wound healing disturbances. We recommend TKA sans tourniquet. Let it bleed!

Introduction:. 20 cases of bone defect have been treated by the induced membrane technique avoiding allograft, microsurgery and amputation. Material and Methods:. 9 cases of long bone defect (humerus and forearm) and 11 cases of bone defect at the hand have been included in this multicentre prospective study (3 centers). The aetiology in 11 cases was trauma, 7 cases were septic nonunions and 2 cases followed tumors. In the hand the bone loss was at least one phalanx, and for long bones the mean defect was 5 cm (3–11). All cases were treated by the induced membrane technique which consists in stable fixation, flap if necessary and in filling the void created by the bone defect by a cement spacer (PMMA). This technique needs a second stage procedure at the 2. nd. month where the cement is removed and the void is filled by cancellous bone. The key point of this induced membrane technique is to respect the foreign body membrane which appeared around the cement spacer and which creates a biologic chamber for the second procedure. Bone union was evaluated prospectively in each case by a surgeon not involved in the treatment, by X-ray and CT scan. Failure was defined as a nonunion at 1 year, or an uncontrolled sepsis at 1 month. Results:. 3 cases failed to achieve bone union, 2 in the hand and 1 in a long bone. No septic complications occurred and all septic cases healed. In 14 cases bone union was achieved with a delay of 5 months (1, 5–12). 2 biopsies allowed us to prove that osteoid tissue was created by the technique. At hand level all fingers have included. At shoulder and elbow level, function reached 75% of motion of the contralateral side. Discussion:. Masquelet first reported 35 cases of large bone defect of tibia nonunion treated by the induced membrane technique which allow filling a bone defect with cancellous bone alone. The cement spacer induces a foreign body membrane (neo periosteum) which constitute a biological chamber. Animal models showed the properties of the membrane: secretion of growths factors (VEGF, TGFbéta1, BMP2) and osteoinductive activitie of the cells. Conclusion:. This technique is useful in emergency or in septic condition where a bone defect cannot be solved by shortening. The technique avoids the use of microsurgery and the limit is the quantity of available cancellous bone

There is no question that at some point many TKAs will be cementless-the question is when. The advantages of cementless TKA include a shorter operative time, no need for a tourniquet, more suitability for MIS, no concern for cement extrusion, and the history of THA. The concerns for cementless TKA include the history to date with cementless TKA (tibia and metal-backed patella), variable bony substrate, surgical cut precision, cost, revision concerns, and the patella (for patella component resurfacers). Cemented total knee arthroplasty remains the gold standard and has proven to provide durable results in most patients. The early experience with cementless tibial fixation was problematic due to tibial micromotion leading to pain and loosening. Screw fixed tibial components had additional problems as portals for polyethylene debris leading to tibial osteolysis. Moreover, metal-backed patellar components were associated with a high failure rate and most surgeons began to cement all three components. Renewed interest in cementless tibial fixation is driven in part by newer materials felt to be more suitable for ingrowth and by the perceived benefit of minimally invasive surgery. One of the concerns in limited exposure total knee arthroplasty is the difficulty in preventing the extravasation of cement posteriorly. If there is evidence-based data that quad sparing non-patella everting and limited incision length facilitates rehabilitation and does not jeopardise outcome, cementless tibial fixation will be a more attractive option in some patients. An additional concern is that the tibial surface is frequently quite variable in terms of the strength of the cancellous bone. Bone cement stabilises those differences and provides a homogeneous platform for load bearing through the tibial component

In the 1960s Sir John Charnley introduced to clinical practice his low friction arthroplasty with a highly polished cemented femoral stem. The satisfactory long term results of this and other cemented stems support the use of cement for fixation. The constituents of acrylic cement remained virtually unchanged since the 1960s. However, in the last three decades, advances in the understanding of cement fixation, mixing techniques, application, pressurization, stem materials and design provided further improvements in the clinical results. The technical changes in cementing technique that proved to be beneficial include femoral preparation to diminish interface bleeding, careful lavage, reduced cement porosity by vacuum mixing, a cement restrictor, pre-heating of the stem and polymer, retrograde canal filling and pressurization with a cement gun, stem centralization and stem geometries that increase the intramedullary pressure and intrusion into the bone of the cement. Some other changes proved to be detrimental and were abandoned, such as the use of Boneloc cement that polymerised at a low temperature, and roughening and pre-coating of stem surface. In recent years there has been a tendency towards an increased use of cementless femoral fixation for primary hip arthroplasty. The shift in the type of fixation followed the consistent, durable fixation obtained with uncemented acetabular cups, ease of implantation and the poor results of cemented femoral fixation of rough and precoated stems. Unlike cementless femoral fixation, modern cemented femoral fixation has numerous advantages: it's versatile, durable and can be used regardless of the diagnosis, proximal femoral geometry, natural neck version, and bone quality. It can be used in combination with antibiotics in patients with a history or predisposition for infection. Intraoperative femoral fractures and postoperative thigh pain are extremely rare. Survivorship has not been surpassed by uncemented femoral fixation and it continues to be my preferred form of fixation. However, heavy, young male patients may exhibit a slightly higher aseptic loosening rate

Stems provide short- and long-term stability to the femoral and tibial components. Poorer epiphyseal and metaphyseal bone quality will require sharing or offloading the femoral and tibial component interfaces with a stem. One needs to use stem technique most appropriate for each individual case because of variable anatomy and bone loss situations. The conflict with trying to obtain stability via the stem is that most stems are cylindrical but femoral and tibial metaphyseal/diaphyseal areas are conical in shape. Viable stem options include fully cemented short and long stems, uncemented long stems, offset uncemented stems, and a hybrid application of a cemented proximal end of longer uncemented diaphyseal engaging stems. Stems are not without their risk. The more the load is transferred to the cortex, the greater the risk of proximal interface stress shielding. A long uncemented stem has similar stress shielding as a short cemented stem. Long diaphyseal engaging stems that are cemented or uncemented have the potential to have end of stem pain, especially if more diaphyseal reaming is done to obtain greater cortical contact. A conical shaped long stem can provide more stability than a long cylindrical stem and avoid diaphyseal reaming. Use of long stems may create difficulty in placement of the tibial and femoral components in an optimal position. If the femoral or tibial components do not allow an offset stem insertion, using a long offset stem or short cemented stem is preferred. The amount of metaphyseal bone loss will drive the choice of stem used. Short cemented stems will not have good stability in poor metaphyseal bone without getting the cement out to the cortex. Long cemented stems provide satisfactory survivorship, however, most surgeons avoid cementing long stems due to the difficulty of removal, if a subsequent revision is required. If the metaphyseal bone is excellent, use of a short cemented stem or long uncemented stem can be expected to have good results. Long fully uncemented stems must have independent stability to be effective, or should be proximally cemented as a hybrid technique. Cases with AOI type IIb and III tibial and femoral defects are best managed with use of metaphyseal cones with short cemented stems or long hybrid straight or offset stems. Some studies also suggest that if the cone is very stable, no stem may be required. My preference is to use a short cemented stem or hybrid conical stem in patients with good metaphyseal bone. If significant metaphyseal bone loss is present, I will use a porous cone with either a short cemented stem, hybrid cylindrical or offset stem depending on the primary stability of the cone and whether the femoral or tibial component can be placed in an optimal position in patients with good metaphyseal bone

Lavage and preparation of the cancellous bony surface can facilitate adequate fixation of components in cemented total knee arthroplasty (TKA). Commonly used techniques for bone preparation such as pulse lavage, apart from adding to the cost, may cause local loss of loose cancellous bone and may even drive contaminants deeper into the tissue when used during TKA. We describe a simple, inexpensive and effective tool of using a sterilised toothbrush for preparing bone surface during cemented TKA. This must be followed by adequate pressurization of cement at the right time to achieve close interdigitation of cement with trabecular bone

As an alternative to total hip arthroplasty (THA), hip resurfacing arthroplasty (HRA) provides the advantage of retaining bone stock. However, femoral component loosening and femoral neck fracture continue to be leading causes of revision in HRA. Surgical technique including cementation method and bone preparation, and patient selection are known to be important for fixation. This study was designed to understand if and to what extent compromise in bone quality and the presence of cysts in the proximal femur contribute to resurfacing component loosening. A finite element (FE) model of a proximal femur was used to calculate the stress in the cement layer. Bone density to Young's modulus relationship was used to calibrate the bone stiffness in the model using computed tomography. A contemporary resurfacing implant (BHR, Smith & Nephew) was used in the FE model. The effect of reduced bone quality (35% reduction relative to normal baseline; osteoporosis threshold) and presence of cysts on stress in the bone cement layer was then assessed using the same FE model. The center of the cyst (a localized spherical cavity 1 cm in diameter) was located directly under the contact patch. Simulations were run with two locations of the center of the cyst, on the surface of the resected bone and 1 cm below it. The surface cyst was filled with bone cement, but the inner cyst was empty. The contact force and location for the model were obtained from instrumented implant studies. Simulations were run representing the peak loads during two activities, jogging and stand-up from seated position. While density reduction of the bone reduced the stress in the CoCr femoral head, the Von-Mises stress in the cement layer was amplified. The peak Von-Mises stress in the cement layer under the contact patch increased more than six times for the jogging activity, and more than ten times for the stand-up activity, relative to values for normal bone density. The impact of cysts on the cement layer stress or the strain distributions in the bone were minimal. The results show a greater risk of failure of the cement layer under conditions of reduced bone density. In contrast cement stresses and bone strains appeared to be relatively immune to a surface cyst filled with bone cement or an empty inner cyst. Contraindications of hip resurfacing include severe osteopenia and multiple cysts of the femoral head, however no strict or quantitative criteria exist to guide patient selection. Research similar to the one presented herein, maybe key to developing better patient selection criteria to reduce risk associated with compromised femoral head fixation

Femoral revision in cemented THA might include some technical difficulties, based on loss of bone stock and cement removal, which might lead to further loss of bone stock, inadequate fixation, cortical perforation or consequent fractures. Cemented THA has become an extremely successful operation with excellent long-term results. Although showing decreasing popularity in North America, it always remained a popular choice for the elderly patients in Europe and other parts of the world. Various older and recent studies presented excellent long-term results, for cemented fixation of the cup as well as the stem. Besides optimal component orientation, a proper cementing technique is of major importance to assure longevity of implant fixation. Consequently a meticulous bone bed preparation assures the mechanical interlock between the implant component, cement and the final bone bed. Pre-operative steps as proper implant sizing/ templating, ensuring an adequate cement mantle thickness, and hypotensive anaesthesia, minimizing bleeding at the bone cement interface, are of major importance. Additionally, femoral impaction grafting, in combination with a primary cemented stem, allows for femoral bone restoration due to incorporation and remodeling of the allograft bone by the host skeleton. Historically, it has been first performed and described in Exeter in 1987, utilizing a cemented tapered polished stem in combination with morselised fresh frozen bone grafts. The technique was refined by the development of designated instruments, which have been implemented by the Nijmegen group from Holland. Indications might include all femoral revisions with bone stock loss, while the Endo-Clinic experience is mainly based on revision of cemented stems. Cavitary bone defects affecting meta- and diaphysis leading to a wide or so called “drain pipe” femora, are optimal indications for this technique, especially in young patients. Contraindications are mainly: septical revisions, extensive circumferential cortical bone loss and noncompliance of the patient. The cement mantle is of importance, as it acts as the distributor of force between the stem and bone graft and seals the stem. A cement mantle of at least 2 mm has shown favorable results. Originally the technique is described with a polished stem. We use standard brushed stems with comparable results. Relevant complications include mainly femoral fractures due to the hardly impacted allograft bone. Subsidence of tapered polished implants might be related to cold flow within the cement mantle, however, could also be related to micro cement mantle fractures, leading to early failure. Subsidence should be less than 5 mm. Impaction grafting might technically be more challenging and more time consuming than cement-free distal fixation techniques. It, however, enables a reliable restoration of bone stock which might especially become important in further revision scenarios in younger patients