Does the Nottingham Hip Fracture Score Help Predict Which Patients Will Benefit From a Modern Modular Hemiarthroplasty for the Treatment of Intracapsular Proximal Femoral Fractures?

Introduction: Hemiarthroplasty for the management of intracapsular neck of femur fractures is common but current practice in the UK still varies regionally and individually. Guided by the National Institute of Health and Care Excellence (NICE) we have observed a move towards modern, modular prostheses such as the Exeter V40 Stem but the use of older, monoblock prostheses such as the Thompsons Hemiarthroplasty remains controversial. Use of the Nottingham Hip Fracture Scores (NHFS) can help surgeons stratify patients according to risk and select the most appropriate prosthesis to meet their individual needs. Materials and Methods: 765 hip hemiarthroplasties were analysed over a 28-month period at a single, high-volume, orthopaedic department in the UK. We calculated the NHFS and recorded the choice of prosthesis. Patients were then followed up for at least a year. Outcomes were mortality and change in residential status. Results: Six hundred and forty-six (446) patients were treated with monoblock prostheses (mean age=85.6; range 62-105). 319 patients received modular prostheses (mean age=81.0; range 61-98). Patients who were selected to receive a monoblock prosthesis were over twice as likely to be dead at a year (32.87% vs. 13.65%) and over twice as likely to require increased assistance with living (50.12% vs. 23.81%). Amongst patients with equivocal NHFS, those who receive a monoblock stem suffered worse outcomes in all but the very highest risk group, who experienced lower mortality (OR=0.71, CI 0.52-0.96) and change in residential status (OR=0.76, CI 0.58-0.99). Conclusion: Nottingham Hip Fracture Score (NHFS) can confer predictable outcomes in hip fracture patients treated with modular stems. Modular stems should be the default choice when performing hemiarthroplasties for intracapsular neck of femur fractures. However, in keeping with other studies, we found that in very old, frail, or co-morbid patients, modular stems are not associated with better survival or return to pre-morbid function.

Modularity of total hip prosthesis and its tribological implications

Purpose The study aims to analyze the fretting phenomenon, manifested at the taper junctions of modular total hip prostheses (THP). Modularity of prostheses implies the micro-movement occurrence. Fractures can arise as a result of the fretting cracking of the prostheses components, affecting durability of modular THPs. Fretting corrosion is associated with the decrease in the clinical acceptance of hip modular implants. Design/methodology/approach Starting from the fretting phenomenon influence on modularity, monoblock THPs and prostheses with modular femoral head recovered from some review surgeries were investigated. Modular prostheses have a taper junction femoral head – femoral stem neck. Investigation consisted in the analysis of fretting wear and fretting corrosion, of the femoral heads’ taper and of the femoral stems’ trunnions. Findings The main result was that the micro-movement that provokes the fretting of the femoral head-femoral stem taper junction analyzed does not have the same direction. It is manifesting in the direction of the axis of the femoral head taper, around this axis or as a composed movement. The authors suspect that this is due to the different design of the taper. In this way, the inclination of the stem’s trunnion into the head hole has a different angular misalignment and may cause greater damages of the taper. Originality/value This result can be a starting point from the improvement of the future taper junctions design that will improve the quality, durability and modularity of THPs.

Pelvic Chondrosarcoma Treated by En Bloc Resection with Patient-Specific Osteotomy Guides and Reimplantation of the Extracorporeally Irradiated Bone as an Osseocartilaginous Structural Orthotopic Autograft: A Report of Two Cases with Description of the Surgical Technique

Primary tumors of the pelvis are considered difficult to treat due to the complex anatomy and the proximity of important neurovascular structures. The surgical armamentarium for the treatment of these tumors has evolved with the help of cutting-edge technology from debilitating hemipelvectomies to solutions such as precise resections guided by patient-specific instruments or computer navigation and reconstruction by modular prostheses, 3D-printed custom-made implants, or orthotopic autograft reimplantation after extracorporeal irradiation. Different combinations of these techniques have been described in the literature with various rates of success. We present two cases of pelvic chondrosarcomas successfully treated by a combination of periacetabular resection with patient-specific osteotomy guides and orthotopic reimplantation of the extracorporeally irradiated autograft resulting in retention of the native hip.

Assessment of Physical Performance and Early Treatment Outcomes after Implantation of Modular Prostheses of Femoral and Tibial Shaft

Background. Tumours of bone diaphyses often require resection followed by bone reconstruction. The use of modular pro­sthe­ses permits early limb loading and rapid improvement in physical performance. The aim of this study was to evaluate the func­tioning of patients and early treatment outcomes after the implantation of modular prostheses. The analysis covered the correlation between the extent of resection, physical performance and the number of perioperative complications. Material and methods. 10 patients (5 women and 5 men) with diaphyseal tumours who had modular prostheses implanted were treated at the Orthopaedic Oncology Department in Brzozów between 2014 and 2018. The mean age of the patients was 51.1 years (range: 26-63 years). Functional outcomes were assessed using the MSTS and the Karnofsky scoring system. A VAS was used to evaluate pain intensity. the extent of resection was also analysed, considering bone length and tumour weight. Results. The mean tumour weight was 374g (150-700g). The length of the implants varied from 10 to 25 cm. The mean dura­tion of hospitalisation was 16 days (14-19 days). At 3 months following the surgery, the intensity of pain had decreased from a mean of 6.8 points to 4.2 points (a decrease of 26% from the pre-operative baseline). The MSTS showed improvement of functional performance from a mean of 10.8 points (36%) to 22.9 points (76%). The Karnofsky scores demonstrated an increase in physical performance from 47 to 67 points (20 points on average). Superficial infection of the wound developed in 1 patient. Conclusions. 1. The treatment of diaphyseal tumours with modular prostheses produces good functional outcomes. 2. The extent of the resection and the size of the implant have an effect on the post-operative physical performance of the patients. 3. Pre­operative evaluation of the weight of the tumour may be helpful in predicting the patient’s post-operative functional status. 4. Phy­sical perfor­mance is better after the resection of femoral vs tibial tumours.

Bone Diaphysis Metastases, the Ways and Results of Surgical Treatment Saving the Joints

Background. A consequence of the progress in oncological treatment is an increasing number of bone complications asso­ciated with metastases. With appropriate choice of oncological treatment and appropriate surgical management, patients may recover their physical function and maintain the previous level of quality of life. Available surgical techniques include intrame­dullary nailing, stabilisation with plates and screws and the use of modular prostheses. Aim of the study: to retrospectively assess the techniques and outcomes of surgical treatment of long bone metastases at the Oncology Orthopaedics Department of the Speciality Hospital in Brzozów, present the possibilities of surgical management and benefits of the chosen method and tentatively choose the most effective approach for restoring function. Material and methods. Between 2013 and 2017, a total of 82 patients were treated for long bone metastases at the Depart­ment of Oncological Orthopaedics. The most common cancers causing bone metastases were breast cancer (37%), myeloma (16%), lung cancer (8%), kidney (15%), prostate (8%), thyroid 4%, colon 1%, uterus 1%, with other sites accounting for 10%. Pathological fractures were diagnosed in 68 patients. Before the surgical treatment, the patients’ quality of life was assessed using the Karnofsky scale, Bollen prognostic scale, severity of pain in a VAS scale, and MSTS performance scale. Metastasis morpho­logy was evaluated with conventional radiographs, CT and PET-CT. Types of surgery comprised intramedullary nailing, the use of plates and screws and the placement of modular prostheses. Patients were divided into three groups with regard to the stabi­li­sation systems used and another three related to tumour location (humerus, femur or tibia). Results. Post-operatively, there was a reduction of pain in the VAS scale. Function (MSTS) was best in patients treated with minimally invasive methods and modular prostheses (p <0.05). An improvement in quality of life in the Karnofsky scale was also noted. The complication rate was 7% and was related to wound healing and thromboembolic complications. Conclusions. 1. Patients with long-bone cancer metastases with pathological fractures or risk of fracture require surgical management. 2. Nailing or modular prosthesis produced the best functional result at 6 weeks post-operatively. 3. All methods of surgical treatment reduced pain and improved the quality of life.

The Indication of Resection-Reconstruction with Tumor Prosthesis for the Young Patient with Osteosarcoma

Introduction. The osteosarcoma represents the most frequently encountered primitive malignant bone tumor, representing 30% of the malignant bone tumors with an unpredictable evolution. Materials and methods. A retrospective study realized over a period of 3 years (Jan. 2016-Jan. 2018), which included 6 patients diagnosed with osteosarcoma and treated through the reconstruction with tumor prosthesis technique in the Orthopaedics and Traumatology Clinic of the University Emergency Hospital in Bucharest. Results. Of the total 6 patients, 5 were male and 1 was a female with ages between 20 and 61 years old, with an average of 30.6 years. The localization of the tumor was at the distal femur (3 cases) and at the proximal tibia (3 cases). In 3 cases, the reattachment of the extensor apparatus of the knee to the prosthesis was needed, while for 3 of the cases, a musculocutaneous flap was created for the coverage of the implant. All the 6 patients were monitored and had postoperative follow-ups at 3, 6 and 12 months by having clinical and imagistic evaluations in search of the eventual local recurrences or metastases in other tissues and organs. The postoperative evaluation of the function of the joint was realized with the Knee Society Score Questionnaire and recorded very good results (76-91) with an average of 82 points. Conclusions. The short-term results of this study about the treatment of the knee osteosarcoma with modular prostheses show that this treatment has a low tumoral recurrence rate and restores the joint function.

Comparison of Stresses in Four Modular Total Knee Arthroplasty Prosthesis Designs

The current study, compares the mechanical performance of four modular TKA prostheses based on von Mises stress distribution in the tibial insert. Three-dimensional finite element (FE) models of a cruciate retaining type modular prosthesis and three posterior stabilized (PS) type modular prostheses namely: anterior slide, modular post and double cam, were developed. A compressive load of 2600 N was applied to the FE models at flexion angles of 00, 150, 300, 600 and 900. Von Mises stress was evaluated on all the modular parts of the prostheses and compared with the yield strength of the corresponding material. Von Mises stress in all the parts were below the yield strength of their corresponding material except for tibial insert of anterior slide design at high flexion angle. Von Mises stress above the yield strength in the tibial insert of anterior slide design, was due to edge loading in the post and it demonstrates the likelihood of mechanical failure by delamination type of wear.