The Fixion expandable nailing system provides an intramedullary fracture fixation solution without the need for locking screws. Proponents of this system have demonstrated shorter surgery times with rapid fracture healing, but several centres have reported suboptimal results with loss of fixation. This is the largest comparative series to be reported to date.

We compared outcomes between 50 consecutive diaphyseal tibial fractures treated with a Fixion device at our institution to an age, sex and fracture configuration matched series of 57 fractures at a neighbouring hospital treated with a conventional interlocked intramedullary nail. Minimum follow up time was 2 years.

Operating time was significantly reduced in the Fixion group (mean 61 minutes, range 20–99) compared to the interlocked group (88 minutes, 52–93), p< 0.00001. The union rate was no different between the Fixion group (93.9%) and the interlocked group (96.5%), p=0.527. Time to clinical and radiological union was significantly faster in the Fixion group (median 85 days, range 42–243) compared to the interlocked group (119, 70–362), p< 0.0001. The overall reoperation rate was lower in the Fixion series (24.5% vs 38.6%, p=0.121), although the majority of reoperations in the interlocked group were more minor, for screw removal. 3 Fixion nails were revised for fixation failure and 2 manipulations were required for rotational deformities after falls; all of these patients were non-compliant with post-operative instructions. There were no fixation failures in the interlocked group. 3 fractures were noted to propagate during inflation of Fixion nails.

The Fixion nail is faster to implant and allows more physiological loading of the fracture, with a faster union time. However, these advantages are offset by a reduction in construct stability. Our results have demonstrated a learning curve with a reduction in complications as our indications were narrowed, avoiding osteoporotic, multifragmentary, unstable fractures and non-compliant patients

Displaced fractures of the radial neck in children can lead to limitation of elbow and forearm movements if left untreated. Several management techniques are available for the treatment of radial neck fractures in children. Open reduction can disturb the blood supply of the soft tissue surrounding the radial head epiphysis and is associated with more complications.

We report our experience of treating 14 children between the age of 4 and 13 years, who had severely displaced radial neck fractures (Judet type 111 and 1V). 12 patients were treated with indirect reduction and fixation using the Elastic Stable Intramedullary Nail (ESIN) technique, (3 with assisted percutaneous K-wire reduction) and 2 had open reduction followed by ESIN fixation of the radial head fragment. This method reduces the need for open reduction and thus the complication rate. Three patients had associated fractures of the same forearm which was also treated surgically at the same time. We routinely immobilised the forearm for two weeks and removed the nail in all cases in an average of 12 weeks. We had no complication with implant removal.

All 14 patients have been followed up for average of 28 months. One patient (7%) developed asymptomatic avascular necrosis (AVN) of the head of radius. Thirteen patients (93%) had excellent result on final review. One patient had neuropraxia of the posterior interosseous nerve which recovered within 6 weeks.

In conclusion we advocate ESIN for the closed reduction and fixation of severely displaced radial neck fractures in children. It remains a useful fixation method even if open reduction is required and allows early mobilisation.

Complex acetabular reconstruction for oncology and bone loss are challenging for surgeons due to their often hostile biological and mechanical environments. Titrating concentrations of silver ions on implants and alternative modes of delivery allow surgeons to exploit anti-infective properties without compromising bone on growth and thus providing a long-term stable fixation. We present a case series of 12 custom acetabular tri-flange and custom hemipelvis reconstructions (Ossis, Christchurch, New Zealand), with an ultrathin plasma coating of silver particles embedded between layers of siloxane (BioGate HyProtect™, Nuremberg, Germany). At the time of reporting no implant has been revised and no patient has required a hospital admission or debridement for a deep surgical site infection. Routine follow up x-rays were reviewed and found 2 cases with loosening, both at their respective anterior fixation. Radiographs of both cases show remodelling at the ilium indicative of stable fixation posteriorly. Both patients remain asymptomatic. 3 patients were readmitted for dislocations, 1 of whom had 5 dislocations within 3 weeks post-operatively and was immobilised in an abduction brace to address a lack of muscle tone and has not had a revision of their components. Utilising navigation with meticulous implant design and construction; augmented with an ultrathin plasma coating of silver particles embedded between layers of siloxane with controlled and long-term generation of silver ion diffusion has led to outstanding outcomes in this series of 12 custom acetabular and hemipelvis reconstructions. No patients were revised for infection and no patients show signs of failure of bone on growth and incorporation. Hip instability remains a problem in these challenging mechanical environments and we continue to reassess our approach to this multifaceted problem

Introduction. The management of fracture-related infection has undergone radical progress following the development of international guidelines. However, there is limited consideration to the realities of healthcare in low-resource environments due to a lack of available evidence in the literature from these settings. Initial antimicrobial suppression to support fracture union is frequently used in low- and middle-income countries despite the lack of published clinical evidence to support its practice. This study aimed to evaluate the outcomes following initial antimicrobial suppression to support fracture union in the management of fracture-related infection. Materials & Methods. A retrospective review of consecutive patients treated with initial antimicrobial suppression to support fracture healing followed by definitive eradication surgery to manage fracture-related infections following intramedullary fixation was performed. Indications for this approach were; a soft tissue envelope not requiring reconstructive surgery, radiographic evidence of stable fixation with adequate alignment, and progression towards fracture union. Results. This approach was associated with successful treatment in 51/55 (93%) patients. Fracture union was achieved in 52/55 (95%) patients with antimicrobial suppression alone. Remission of infection was achieved in 54/55 (98%) patients following definitive infection eradication surgery. Following antibiotic suppression, 6/46 (13%) pathogens isolated from intra-operative samples demonstrated multi-drug resistance. Conclusions. Initial antimicrobial suppression to support fracture healing followed by definitive infection eradication surgery was associated with successful treatment in 93% of patients. The likelihood of remission of infection increases when eradication surgery is performed in a healed bone. This approach was not associated with an increased risk of developing multi-drug-resistant infections compared to contemporary bone infection cohorts in the published literature

Introduction. The Oxford Unicompartmental Knee Replacement (OUKA) is the most popular unicompartmental knee replacement (UKR) in the New Zealand Joint Registry with the majority utilising cementless fixation. We report the 10-year radiological outcomes. Methods. This is a prospective observational study. All patients undergoing a cementless OUKA between May 2005 and April 2011 were enrolled. There were no exclusions due to age, gender, body mass index or reduced bone density. All knees underwent fluoroscopic screening achieving true anteroposterior (AP) and lateral images for radiographic assessment. AP assessment for the presence of radiolucent lines and coronal alignment of the tibial and femoral components used Inteliviewer radiographic software. The lateral view was assessed for lucencies as well as sagittal alignment. Results. 687 OUKAs were performed in 641 patients. Mean age at surgery was 66 years (39–90yrs), 382 in males and 194 right sided. 413 radiographs were available for analysis; 92 patients had died, 30 UKRs had been revised and 19 radiographs were too rotated to be analysed the remainder were lost to follow-up. Mean radiograph to surgery interval was 10.2 years (7.1–16.2yrs). RLLs were identified in zone 1 (3 knees), zone 2 (2 knees), zone 3 (3 knees), zone 5 (3 knees), zone 6 (2 knees) and zone 7 (42 knees). No RLL had progressed, and no case had any osteolysis or prosthesis subsidence. Alignment in the coronal plane: mean 2.90° varus (9.30° varus - 4.49° valgus) of the tibial component to the tibial anatomic axis and the femoral component in mean 4.57° varus (17.02° varus - 9.3° valgus). Sagittal plane posterior tibial slope was a mean 6.30° (0.44° -13.60° degrees) and mean femoral component flexion of 8.11° (23.70° flexion – 16.43° extension). Conclusion. The cementless OUKA demonstrates stable fixation with low revision rates at our centre supporting results earlier published by the design centre

Aim. The treatment of fracture-related infections (FRI) focuses on obtaining fracture healing and eradicating infection to prevent osteomyelitis. Treatment guidelines include removal, exchange, or retention of the implants used according to the stability of the fracture and the time from the infection. Infection of a fracture in the process of healing with a stable fixation may be treated with implant retention, debridement, and antibiotics. Nonetheless, the retention of an intramedullary nail is a potential risk factor for failure, and it is recommended to exchange or remove the nail. This surgical approach implies additional life-threatening risks in elderly fragile hip fracture patients. Our study aimed to analyze the results of implant retention for the treatment of infected nails in elderly hip fracture patients. Methods. Our retrospective analysis included patients 65 years of age or older with an acute fracture-related infection treated with implant retention from 2012 to 2020 in 6 Spanish hospitals with a minimum 1-year follow-up. Patients that required open reduction during the initial fracture surgery were excluded. Variables included in our analysis were patient demographics, type of fracture, date of FRI diagnosis, causative microorganism, and outcome. Treatment success was defined as fracture healing with infection eradication without the need for further hospitalization. Results. A total of 48 patients were identified. Eight patients with open reduction were excluded and 11 did not complete a 1-year follow-up. Out of the 29 remaining patients, the mean age was 81.5 years, with a 21:9, female to male ratio. FRI was diagnosed between 10 and 48 days after initial surgery (mean 26 days). Treatment success was achieved in 24 patients (82.7%). Failure was objectivated in polymicrobial infections or infections caused by microorganisms resistant to antibiofilm antibiotics. Seven patients required more than one debridement with a success rate of 57%. Twelve patients had an infection diagnosed after 21 days from the initial surgery and implant retention was successful in all of them. Conclusion. Our results suggest implant retention is a valid therapeutic approach for fracture-related infection in elderly hip fracture patients treated by closed reduction and intramedullary nailing

Aim. Repeat revision surgery of total hip or knee replacement may lead to massive bone loss of the femur. If these defects exceed a critical amount a stable fixation of a proximal or distal femur replacement may not be possible. In these extraordinary cases a total femur replacement (TFR) may be used as an option for limb salvage. In this retrospective study we examined complications, revision free survival (RFS), amputation free survival (AFS) and risk factors for decreased RFS and AFS following a TRF in cases of revision arthroplasty with a special focus on periprosthetic joint infection (PJI). Method. We included all implantations of a TFR in revision surgery from 2006–2018. Patients with a primary implantation of a TFR for oncological indications were not included. Complications were classified using the Henderson Classification. Primary endpoints were revision of the TFR or disarticulation of the hip. The minimum follow up was 24 month. RFS and AFS were analyzed using Kaplan-Meier method, patients´ medical history was analyzed for possible risk factors for decreased RFS and AFS. Results. After applying the inclusion criteria 58 cases of a TFR in revision surgery were included with a median follow-up of 48.5 month. The median age at surgery was 68 years and the median amount of prior surgeries was 3. A soft tissue failure (Henderson Type I) appeared in 16 cases (28%) of which 13 (22%) needed revision surgery. A PJI of the TFR (Henderson Type IV) appeared in 32 cases (55%) resulting in 18 (31%) removals of the TFR and implantation of a total femur spacer. Disarticulation of the hip following a therapy resistant PJI was performed in 17 cases (29%). The overall 2-year RFS was 36% (95% confidence interval(CI) 24–48%). Patients with a Body mass Index (BMI) >30kg/m² had a decreased RFS after 24 month (>30kg/m² 11% (95%CI 0–25%) vs. <30kg/m² 50% (95%CI 34–66%)p<0.01). The overall AFS after 5 years was 68% (95%CI 54–83%). A PJI of the TFR and a BMI >30kg/m² was significantly correlated with a lower 5-year AFS (PJI 46% (95%CI 27–66%) vs no PJI 100%p<0.001) (BMI >30kg/m² 30% (95% KI 3–57%) vs. <30km/m² 85% (95% KI 73–98%)p<0.01). Conclusions. A TFR in revision arthroplasty is a valuable option for limb salvage but complications in need of further revision surgery are common. Patients with a BMI >30kg/m² should be informed regarding the increased risk for revision surgery and loss of extremity before operation

Introduction. Fibrous dysplasia is a pathological condition, where normal medullary bone is replaced by fibrous tissue and small, woven specules of bone. Fibrous dysplasia can occur in epiphysis, metaphysis or diaphysis. Occationally, biopsy is necessary to establish the diagnosis. We present a review of operative treatment using the Ilizarov technique. The management of tibial fibrous dysplasia in children are curettage or subperiosteal resection to extra periosteal wide resection followed by bone transport. Materials and Methods. A total of 18 patients were treated between 2010 – 2020; 12 patients came with pain and 6 with pain and deformity. All patients were treated by Ilizarov technique. Age ranges from 4–14 years. 12 patients by enbloc excision and bone transportation and 6 patients were treated by osteotomy at the true apex of the deformity by introducing the k/wires in the medullary cavity with stable fixation by Ilizarov device. The longest duration for bone transport was 16 weeks (14–20 weeks) for application, after deformity correction was 20 weeks. We have never used any kind of bone grafts. Results. All the 18 patients were treated successfully by Ilizarov compression distraction device. The patients with localized tibial pathology with deformity had the shortest period on the Ilizarov apparatus, 14 weeks. Conclusions. Preservation and bone regeneration by distraction histogenesis constitutes a highly conservative limb saving surgery. Patients with bone defects of <10 cm, a great deal of preserved healthy tissue and good prognosis are good candidates for these methods

Aim. External fixator knee arthrodesis is a salvage procedure mainly used in cases of end-stage infected total knee replacement (iTKR). A stable fixation combined with bone-ends compression is basic to achieve knee fusion in such a scenario but providing enough stability can be challenging in the presence of severe bone loss after multiple previous procedures. Compared with monoplanar configuration, a biplanar frame achieves improved coronal stiffness, while providing the advantages of good access to the wound and allowance of early ambulation. Our primary hypothesis stated that a biplanar frame would achieve higher and quicker fusion rate than a monolateral configuration. Method. We conducted a retrospective cohort study examining patients managed with biplanar external fixator knee fusion due to non-revisable iTKR between 2014 and 2018. We compared this group of patients with a historical cohort-control patient who had been previously published by our unit in 2013, since we switched from a monoplanar to a biplanar configuration for the management of this kind of complex end-stage iTKR. Primary end-points were fusion rate, time to achieve bone fusion and infection eradication rate. Limb-length discrepancy, pain level, patient satisfaction, and health-related quality of life were also evaluated. Results. A total of 29 cases were finally included; 8 patients were managed with a bilateral external fixator and 21 patients were managed with a monoplanar external fixator. In the biplanar configuration group, infection was eradicated in 100% of the patients, and fusion was achieved in all cases after 5.24 months on average. In comparison, in the monolateral configuration group, infection was eradicated in 18 (86%) out of 21, whereas fusion was achieved in 17 (81%) of the patients after a mean of 10.3 months (range, 4–16). Such difference was statistically significant (p<0.05). In both groups, postoperative pain was mild (VAS score 2,25 and 3,4, respectively) and patients expressed a high degree of satisfaction once fusion was achieved. Conclusions. External fixation knee fusion is a useful limb-salvage procedure in end-stage cases of knee PJI. According to our data, the use of a biplanar configuration allows us to reduce in half (10.3 vs 5.2 months, p<0.05) the time needed to achieve the solid bone fusion in such a complex scenario. In this cohort of previously multi-operated patients, the satisfaction is high, and the level of pain is low if a solid bone fusion free of infection is achieved

The purpose of this study is to determine the re-operation rate following plate fixation of the olecranon with contoured anatomic plates. Plate fixation of the olecranon allows for management of different fracture patterns as well as osteotomies with anatomic reduction and stable fixation for early elbow mobilization. However, olecranon hardware prominence can be troublesome. Our hypothesis was with the newer generation of low profile contoured anatomic plates, the rate of hardware removal should be lower compared to previously described literature. Retrospective review for patients treated with operative fixation of the olecranon between 2010 and 2015 in the Edmonton zone was identified using population level administrative data. Radiographic screening of these patients was then carried out to identify those who received plate fixation. Fracture patterns were also characterized. Chart reviews followed to determine the indications for re-operation and other post-operative complications. Main outcome measures were re-operation rate and their indications, including hardware prominence. During the screening process, 600 surgically treated olecranon patients were identified and 321 patients were found to have plate fixation of the olecranon. Chart review determined 90 patients had re-operations demonstrating a 28% re-operation rate. Re-operation due to hardware prominence was found to be 15.6%. Other indications included hardware failure (5.3%), infection (2.8%), or contracture (2.8%). Compared to patients that did not require re-operation, the re-operation group had a higher incidence of Type III olecranon fractures (17.4% vs 8.4%, p = 0.036) and Monteggia pattern injuries (13.5% vs 4.9%, p = 0.008). Recent heteregenous data suggests the hardware removal rate related to implant prominence is between 17–54%. Compared to the literature, this study demonstrated a lower rate at 15.6% with contoured anatomic plating. Also, those with more complex fracture patterns were more likely to require re-operation

Introduction. Reverse total shoulder arthroplasty (RTSA) is rapidly being adopted as the standard procedure for a growing number of shoulder arthropathies. Though short-term outcomes are promising, mid- and long-term follow-ups present a number of complications – among them, humeral stem and glenosphere component loosening. Though not the primary complication, previously reported aseptic loosening required revision in 100% of cases. As the number of patients undergoing RTSA increases, especially in the younger population, it is important for surgeons to identify and utilize prostheses with stable long-term fixation. It has previously been shown in the hip and knee literature that implant migration in the first two years following surgery is predictive of later failure due to loosening in the 5=10-year postoperative window. The purpose of this study is to, for the first time, evaluate the pattern and total magnitude of implant migration in reverse shoulder arthroplasty using the gold standard imaging technique radiostereometric analysis (RSA). Methods. Forty patients were prospectively randomized to receive either a cemented or press-fit humeral stem, and a glenosphere secured to the glenoid with either autologous bone graft or 3D printed porous titanium for primary reverse total shoulder arthroplasty. Following surgery, participants are imaged using RSA, a calibrated, stereo x-ray technique. Radiographs are acquired at 6 weeks (baseline), 3 months, 6 months, 1 year, and 2 years. Migration of the humeral stem and glenosphere at each time point is compared to baseline. Migration of the prostheses is independently compared between humeral stem fixation groups and glenosphere fixation groups using a two-way repeated measures ANOVA with Tukey's test for multiple comparisons. Results. Follow-ups are ongoing and preliminary results are presented. Significant differences were observed at the 6-month and 1-year time points for superior-inferior translation (p = 0.0067, p = 0.0048), and total three-dimensional translation (p = 0.0011, p = 0.0272) between humeral stems, with press-fit humeral stems subsiding significantly more than cemented stems. Migration between the 6-month and 1-year time points was minimal for both stem fixation groups (less than 0.2 mm). No significant differences were observed along any axis at any time point for the glenosphere fixation groups. Conclusion. There is a trend towards increased subsidence with the use of press-fit stems compared to cemented stems in the first six months postoperatively, as is expected. Both implant fixation techniques demonstrate stability from six months through one year, and this trend is expected through two-year follow-up. Similarly, both glenosphere fixation techniques demonstrate immediate and stable fixation through one year

Large cartilage lesions in younger patients can be treated by fresh osteochondral allograft transplantation, a surgical technique that relies on stable initial fixation and a minimum chondrocyte viability of 70% in the donor tissue to be successful. The Missouri Osteochondral Allograft Preservation System (MOPS) may extend the time when stored osteochondral tissues remain viable. This study aimed to provide an independent evaluation of MOPS storage by evaluating chondrocyte viability, chondrocyte metabolism, and the cartilage extracellular matrix using an ovine model. Femoral condyles from twelve female Arcott sheep (6 years, 70 ± 15 kg) were assigned to storage times of 0 (control), 14, 28, or 56 days. Sheep were assigned to standard of care [SOC, Lactated Ringer's solution, cefazolin (1 g/L), bacitracin (50,000 U/L), 4°C storage] or MOPS [proprietary media, 22-25°C storage]. Samples underwent weekly media changes. Chondrocyte viability was assessed using Calcein AM/Ethidium Homodimer and reported as percent live cells and viable cell density (VCD). Metabolism was evaluated with the Alamar blue assay and reported as Relative Fluorescent Units (RFU)/mg. Electromechanical properties were measured with the Arthro-BST, a device used to non-destructively compress cartilage and calculate a quantitative parameter (QP) that is inversely proportional to stiffness. Proteoglycan content was quantified using the dimethylmethylene blue assay of digested cartilage and distribution visualized by Safranin-O/Fast Green staining of histological sections. A two-way ANOVA and Tukey's post hoc were performed. Compared to controls, MOPS samples had fewer live cells (p=0.0002) and lower VCD (p=0.0004) after 56 days of storage, while SOC samples had fewer live cells (p=0.0004, 28 days; p=0.0002, 56 days) and lower VCD (p=0.0002, 28 days; p=0.0001, 56 days) after both 28 and 56 days (Table 1). At 14 days, the percentage of viable cells in SOC samples were statistically the same as controls but VCD was lower (p=0.0197). Cell metabolism in MOPS samples remained the same over the study duration but SOC had lower RFU/mg after 28 (p=0.0005) and 56 (p=0.0001) days in storage compared to controls. These data show that MOPS maintained viability up to 28 days yet metabolism was sustained for 56 days, suggesting that the conditions provided by MOPS storage allowed fewer cells to achieve the same metabolic levels as fresh cartilage. Electromechanical QP measurements revealed no differences between storage methods at any individual time point. QP data could not be used to interpret changes over time because a mix of medial and lateral condyles were used and they have intrinsically different properties. Proteoglycan content in MOPS samples remained the same over time but SOC was significantly lower after 56 days (p=0.0086) compared to controls. Safranin-O/Fast Green showed proteoglycan diminished gradually beginning at the articular surface and progressing towards bone in SOC samples, while MOPS maintained proteoglycan over the study duration (Figure 1). MOPS exhibited superior viability, metabolic activity and proteoglycan retention compared to SOC, but did not maintain viability for 56 days. Elucidating the effects of prolonged MOPS storage on cartilage properties supports efforts to increase the supply of fresh osteochondral allografts for clinical use. For any figures or tables, please contact the authors directly

Patients undergoing revision surgery of a primary total hip arthroplasty often exhibit bone loss and poor bone quality, which make achieving stable fixation and osseointegration challenging. Implant components coated in porous metals are used clinically to improve mechanical stability and encourage bone in-growth. We compared ultra-porous titanium coatings, known commercially as Gription and Porocoat, in an intra-articular model by press-fitting coated cylindrical implants into ovine femoral condyles and evaluating bone in-growth and fixation strength 4, 8 and 16 weeks post-operatively. Bilateral surgery using a mini-arthrotomy approach was performed on twenty-four Dorset-Rideau Arcott rams (3.4 ± 0.8 years old, 84.8 ± 9.3 kg) with Institutional Animal Care Committee approval in accordance with the Canadian Council on Animal Care. Cylindrical implants, 6.2 mm in diameter by 10 mm in length with surface radius of curvature of 35 mm, were composed of a titanium substrate coated in either Porocoat or Gription and press-fit into 6 mm diameter recipient holes in the weight-bearing regions of the medial (MFC) and lateral (LFC) femoral condyles. Each sheep received 4 implants; two Gription in one stifle (knee) and two Porocoat in the contralateral joint. Biomechanical push-out tests (Instron ElectroPuls E10000) were performed on LFCs, where implants were pushed out relative to the condyle at a rate of 2 mm/min. Force and displacement data were used to calculate force and displacement at failure, stiffness, energy, stress, strain, elastic modulus, and toughness. MFCs were fixed in 70% ethanol, processed undecalcified, and polished sections, approximately 70 µm thick (Exakt Micro Grinding system) were carbon-coated. Backscattered electron images were collected on a scanning electron microscope (Hitachi SU3500) at 5 kV and working distance of 5 mm. Bone in-growth within the porous coating was quantified using software (ImageJ). Statistical comparisons were made using a two-way ANOVA and Fisher's LSD post-hoc test (Statistica v.8). Biomechanical evaluation of the bone-implant interface revealed that by 16 weeks, Gription-coated implants exhibited higher force (2455±1362 N vs. 1002±1466 N, p=0.046) and stress (12.60±6.99 MPa vs. 5.14±7.53 MPa, p=0.046) at failure, and trended towards higher stiffness (11510±7645 N/mm vs. 5010±8374 N/mm, p=.061) and modulus of elasticity (591±392 MPa vs. 256±431 MPa, p=0.61). Similarly, by 16 weeks, bone in-growth in Gription-coated implants was approximately double that measured in Porocoat (6.73±3.86 % vs. 3.22±1.52 %, p=0.045). No statistically significant differences were detected at either 4 nor 8 weeks, however, qualitative observations of the exposed bone-implant interface, made following push-out testing, showed more bony material consistently adhered to Gription compared to Porocoat at all three time points. High variability is attributed to implant placement, resulting from the small visual window afforded during surgery, unique curvatures of the condyles, and presence of the extensor digitorum longus tendon which limited access to the LFC. Ultra-porous titanium coatings, know commercially as Gription and Porocoat, were compared for the first time in a challenging intra-articular ovine model. Gription provided superior fixation strength and bone in-growth, suggesting it may be beneficial in hip replacement surgeries where bone stock quality and quantity may be compromised

The goals of revision arthroplasty of the hip are to restore the anatomy and achieve stable fixation for new acetabular and femoral components. It is important to restore bone stock, thereby creating an environment for stable fixation for the new components. The bone defects encountered in revision arthroplasty of the hip can be classified either as contained (cavitary) or uncontained (segmental). Contained defects on both the acetabular and femoral sides can be addressed by morselised bone graft that is compacted into the defect. Severe uncontained defects are more of a problem particularly on the acetabular side where bypass fixation such as distal fixation on the femoral side is not really an alternative. Most authors agree that the use of morselised allograft bone for contained defects is the treatment of choice as long as stable fixation of the acetabular component can be achieved and there is a reasonable amount of contact with bleeding host bone for eventual ingrowth and stabilisation of the cup. On the femoral side, contained defects can be addressed with impaction grafting for very young patients or bypass fixation in the diaphysis of the femur using more extensively coated femoral components or taper devices. Segmental defects on the acetabular side have been addressed with structural allografts for the past 15 to 20 years. These are indicated in younger individuals with Type 3A defects. Structural grafts are unsuccessful in Type 3B defects. Alternatives to the structural allografts are now being utilised with shorter but encouraging results in most multiply operated hips with bone loss. New porous metals such as trabecular metal (tantalum), which has a high porosity similar to trabecular bone and also has a high coefficient of friction, provide excellent initial stability. The porosity provides a very favorable environment for bone ingrowth and bone graft remodeling. Porous metal acetabular components are now more commonly used when there is limited contact with bleeding host bone. Porous metal augments of all sizes are being used instead of structural allografts in most situations. On the femoral side, metaphyseal bone loss, whether contained or uncontained, is most often addressed by diaphyseal fixation with long porous or tapered implants, modular if necessary. Distal fixation requires at least 4 centimeters of diaphyseal bone and in Type IV femurs, a choice must be made between a mega prosthesis or a proximal femoral allograft. The proximal femoral allograft can restore bone stock for future surgery in younger patients. The mega prosthesis which is more appropriate in the older population may require total femoral replacement if there is not enough diaphyseal bone for distal fixation with cement. Cortical struts are used for circumferential diaphyseal bone defects to stabilise proximal femoral allografts, to bypass stress risers and to serve as a biological plate for stabilising peri-prosthetic fractures

Purpose. Isolated fractures of femoral condyle in the coronal plane (Hoffa fracture) is rare and is surgically challenging to treat. 44 patients were operated between 2004–2014. The aim was to retrospectively assess the fracture patterns, fixation done and functional outcome. Methods. All injuries resulted from direct trauma to the knee out of which 36 were due to road traffic accidents.38 were closed injuries and the rest open.35 involved lateral condyle, 8 involved medial condyle and one was bicondylar type. All were anatomically reduced with fixation decided based on preoperative radiographs, CT scan and intra-op observation. Early passive motion and isometric exercises were started but kept non-weight bearing for 6–8 weeks. The mean follow up period was five years. Outcomes were measured using Neer's scoring system and International Knee Society Documentation Committee (IKDC) Functional Score. Results. 26 patients had excellent outcome, 14 had satisfactory and 4 had unsatisfactory outcome which corresponded with the specified fracture severity pattern. Uniformly excellent results were obtained in all simple pattern fractures, whereas comminuted fracture patterns were more challenging to treat with variable outcomes. Conclusion. In our retrospective observational study, we found that each fracture had specific pattern which dictated the treatment plan and the prognosis. Subsequently we grouped the fractures and proposed a classification system that would specify the pattern of fracture and dictate the type of fixation preferred. We conclude that therapeutic outcome is significantly affected by the amount of articular surface comminution, posterior cortex comminution, attainment of anatomical reduction and stable fixation

Introduction. Open wedge high tibial osteotomy (OWHTO) is an operation by the proper load re-distribution in the treatment for medial uni-compartmental arthritis of the knee joint. However, for the proper load re-distribution, stable fixation is mandatory. For the stable fixation, plate should be contoured to the bony surface and screws should be inserted from the central area of the medial side to the hinge area of the lateral side in the proximal fragment because most failures occur at the relatively lesser supported lateral hinge area. Therefore, the purpose of this study was to evaluate the screw insertion angle and orientation that is inserted to the direction of the lateral hinge with an anatomical plate that is post-contoured with a surface geometry of the proximal tibia after the OWHTO. The hypothesis of this study was that the position and orientation would be different according to the correction degree (median value 10 mm) and surgical technique (uni-planar vs bi-planar). Materials and Methods. Thirty-one uni-planar and thirty-eight bi-planar osteotomies were evaluated. Postoperative CT data obtained after OWHTO were used for the 3D reconstruction of the proximal tibia. Anterior dimension (L1) and posterior dimension (L2) of the proximal tibia were measured in sagittal plane from tibial spine. Screw insertion points using four holes were even distributed using L1 and L2 value. As screw insertion angle was set from four holes to lateral hinge of the ‘Safe Zone’. Those four angles were measured in the axial and coronal plane. These were compared according to the correction degree and surgical technique. Results. Anterior AP dimension ‘L1'and posterior AP dimension ‘L2'were measured 24.0 ± 3.7 mm, 22.6 ± 3.1 mm. Angulations of screw from respectively screw hole to lateral hinge were measured 11.3 ± 1.7°, 3.5 ± 1.3°, 3.1 ± 1.5°, and 9.5 ± 1.1° in the axial plane and 81.5 ± 6.0°, 101.5 ± 2.6°, 90.8 ± 3.7°, and 99.2 ± 2.8° in coronal plane, respectively. None of the comparisons were statistically different, regardless of the correction degree and operative technique (Table1). Conclusions. Range of screw angulation showed regular pattern according to the site of the screw hole and it was not different, regardless of the correction degree and operative technique. This study provided range of the screw angulation by the anatomical surface modeling. Future study would give additional benefit for the optimal screw angle and stability such as finite element analysis or other methods

Ten to 15% of the pelvic girdle tumors are primary malignant bone tumors, while about 80% are osseous metastases. Due to improved function, enhanced quality of life, and acceptable local recurrence rates, limb salvage surgery has replaced external hemipelvectomies in many cases of primary malignancies. However, large segmental bony defects and poor bone quality due to the disease process itself and subsequent treatment (i.e. chemotherapy and radiation) can make stable implant fixation difficult when performing a total hip arthroplasty (THA) for oncologic periacetabular lesions with concurrent fractures. Various methods are available to reconstruct the hemipelvis, and include large structural allografts, allograft-prosthetic composites (APCs), custom-made endoprostheses, modular saddle prostheses, and modular hemipelvis endoprostheses. However, short- and mid-term results from our institution indicate that tantalum reconstructions with adjuvant screw fixation and supplemental reinforcement cages provide reasonable improvement in clinical outcomes and stable fixation in situations with massive bone loss and compromised bone quality. On the femoral side, cemented fixation remains a viable option (including proximal femoral replacements), but uncemented distal fixation with extensively-porous coated cylindrical stems or modular fluted tapered stems can be considered if the disease process (or subsequent treatment) primarily affects the proximal femur. In addition to long-term fixation, post-operative dislocations remain a significant concern given the often compromised abductor mechanism

Purpose. A Trabecular Metal Modular Acetabular System (Zimmer, Warsaw, Indiana, USA) is a peripheral rim expansion (elliptical) cup, i.e. a non-hemispherical cup. Radiologically a non-hemispherical cup may be deferent from other conventional hemispherical cups. We reviewed radiological findings of a Trabecular Metal Modular Acetabular System chronologically. Methods. Twenty six patients with osteoarthritis underwent primary total hip arthroplasty (THA) using a Trabecular Metal Modular Acetabular System from 2011 to April 2013. Twenty five patients (follow-up rate: 96.2%) 31 hips could be followed-up over a year were registered. In common, the diameter of every femoral head was 32 mm. We planned the acetabular cup inclination angle to be 45-degree, the cup coverage with host-bone (cup-CE angle) to be over 10-degree, and high hip center was allowed up to 20mm. In case of the cup-CE angle under 10-degree, an acetabular cup was placed medially using Dorr's medial protrusio technique. We established the medial protrusion angle indicating the degree of medial protrusion of an acetabular cup over the pelvic internal wall. The medial protrusion angle was defined by the center point of THA (C) and the 2 cross-points (X. 1. , X. 2. ) which the outline of an acetabular cup crosses the Kohler's line (Figure 1). The cup anteversion angle was measured by the method of Lewinnek, and the cup fixation was evaluated according to the Tompkin's classification. Results. The average follow-up period was 1 year and 3 months (1y1m to 2y8m). The mean diameter of the cup was 54 (48 to 56) mm. Seven high-hip center joints were recognized (2 to 11 mm). The average of cup inclination angle was 42 (32 to 52) degree, of cup anteversion angle was 14 (5 to 36) degree, and of cup CE angle was 25 (−14 to 45) degree. Dorr's medial protrusio technique was necessary in 18 hips. In these 18 hips, the average of medial protrusion angle was 57 (24 to 70) degree. In 4 hips of cup-CE angle less than 10 degree, acetabular bulky bone graft was added. All 31 hips showed the stable fixation, even in 18 hips undergone medial protrusio technique. There was none of hips with migration and/or rotation of an acetabular cup. Radiolucent zone was found in the zone-C of 8 hips. The width of radiolucent zone of all 8 hips was less than 2mm. In these 8 hips, medial protrusio technique was done in 5 hips, and high hip center was found in 3 hips. The radiolucency appeared at postoperatively 2–3 months and disappeared by postoperatively 12 months. Conclusions. All hips showed rigid fixation of a Trabecular Metal Modular Acetabular System in short-term observation. Even in the hips performed Dorr's medial protrusio technique, a Trabecular Metal Modular Acetabular System reached the stable fixation. Radiolucent zone was found transiently in the zone-C of 8 hips (25.8%) and disappeared by postoperatively 12 months. However our series was small and the observation period was short, our results implied that the fixation of a Trabecular Metal Modular Acetabular System was not affected adversely from Dorr's medial protrusio technique

Introduction. To utilize existing cancellous bone for initial stability, custom-made stems were implanted without reaming and rasping. This study reviewed the results of this non-reaming technique. Methods. One hundred and fifty-three hips (138 patients) were followed-up for an average of 12 years (range, 8 to 18). Average age at the surgery was 59 (range, 19 to 78). Seventy percent of the etiologies were dysplastic hips including 17 hips after femoral osteotomy. The Ti-6Al-4V stems were designed using CT data and directly inserted into the femora without reaming and rasping. The stems were coated with hydroxyapatite on the porous coating at proximal 1/3. Harris hip score was used for clinical evaluation. Results. The average preoperative Harris hip score was 44 points. At the most recent follow-up, the score was 90 points. One hundred and fifty-one hips were evaluated as bone-ingrown fixation and 2 hips were evaluated as stable fibrous fixation. The average subsidence was 0.7mm. Grade 2 or 3 stress shielding described by Engh was observed in nineteen hips. The average cortical ratio of the hips evaluated as severe stress shielding was statistically smaller than that of the hips without severe stress shielding. Osteolysis was observed around the stem in 17 hips. Discussion and Conclusions. In conclusion, the proximal press-fit of the custom-made stem secured a stable fixation with non-reaming technique. Although the results obtained with the custom-made stem system were excellent over an average follow-up period of 9 years, stress shielding is still an issue

Peri-prosthetic fractures above a TKA are becoming increasingly more common, and typically occur at the junction of the anterior flange of the femoral component and the osteopenic metaphyseal distal femur. In the vast majority of cases, the TKA is well fixed and has been functioning well prior to fracture. For fractures above well-fixed components, internal fixation is preferred. Fixation options include retrograde nailing or lateral plating. Nails are typically considered in arthroplasties that allow intercondylar access (“open box PS” or CR implants) and have sufficient length of the distal fragment to allow multiple locking screws to be used. This situation is rare, as most distal fragments are quite short. If a nail is chosen, use of a long nail is preferred, since it allows the additional fixation and alignment that diaphyseal fill affords. Short nails should be discouraged since they can “toggle” in the meta-diaphysis and do not engage the diaphysis to improve coronal alignment. Plates can be used with any implant type and any length of distal fragment. The challenge with either fixation strategy is obtaining stable fixation of the distal fragment while maintaining length, alignment, and rotation. Fixation opportunities in the distal fragment can be limited due to obstacles caused by femoral component lugs, boxes, stems, cement mantles, and areas of stress shielding or osteolysis. Modern lateral locked plates can be inserted in a biologically friendly submuscular extra-periosteal fashion. The goal of fixation is to obtain as many long locked screws in the distal fragment as possible. High union rates have been reported with modern locked plating and nailing techniques, however, biplanar fluoroscopic vigilance is required to prevent malalignments, typically valgus, distraction, and distal fragment hyperextension. For certain fractures, distal femoral replacement (DFR) is a wise choice. The author reserves DFR for situations where internal fixation is likely to fail (severe distal osteolysis, severe osteopenia) or for cases where it has already failed (nonunion). Obviously, if the implant is loose, revision is indicated, and typically the distal bone loss is so severe that a distal femoral replacement is indicated. The author prefers cemented constructs and routinely adds antibiotics to the cement mixture. Careful attention to posterior dissection of the distal fragment is recommended to avoid neurovascular injury. Cementing the femoral component in the proper amount of external rotation is important to allow central patellar tracking. The available literature demonstrates excellent functional results with these reconstructions, however, complications are not uncommon. Infection and extensor mechanism complications are the most frequent complications and are best avoided. In summary, ORIF remains the treatment of choice for these fractures, however, for cases where ORIF is likely to fail, or has failed, DFR remains a predictable salvage option