Implant-associated Complications Research Articles

Rotationally stable screw anchor (RoSA) vs. Gamma3 Nail (G3N) in pertrochanteric femoral fractures : Afunctional outcome analysis

The pertrochanteric femoral fracture (PFF) represents one of the most common fracture types throughout Germany. To enable early mobilization of patients, the primary surgical goal is load-stable osteosynthesis. Implant failure still represents the largest group of implant-related complications (>80%). The aim of the study was to document and analyze the influence of the implant on the functional outcome and an evaluation of the rotationally stable screw anchor (RoSA) vs. Gamma3 nail. In aretrospective study 43patients with PFF (AO 31A1-A3) were included in the study. The influence of the implant on the functional outcome was assessed by 2standardized questionnaires (SF-36, NMS (New Mobility Score)) and analyzed in aretrospective evaluation. In the study no significant differences in functional outcome scores ≥ 1year after osteosynthesis of the PFF could be shown depending on the implant used. There is an overall tendency for abetter outcome in the G3N group. In the literature the superiority of intramedullary nailing over extramedullary implants is continually discussed. Implant failure is still the most frequent complication. In intramedullary implants, such as the G3N, the primary cause is failure of the head-neck component. For conventional extramedullary implants the biomechanical properties on the femoral shaft also pose a challenge in the case of unstable PFF. The further development of the RoSA to an intramedullary implant could combine the advantages of intramedullary load carriers with the advantages of the blade-screw combination in the head-neck fragment and lead to a reduction in implant-associated complications.

Readmissions at Thirty-Days and One-Year for Implant-Associated Complications following Primary Total Hip and Knee Arthroplasty: A Population-Based Study of 34,392 Patients Across Austria

IntroductionThe primary aim of this study was to assess 30-day and one-year rates for unplanned readmission due to implant-associated complications following total hip (THA) or total knee arthroplasty (TKA) in Austria. Secondary endpoints were reasons for readmission and differences in revision risk depending on demographics and hospital size. MethodsData on patients receiving THA (n = 18,508) or TKA (n = 15,884) in orthopaedic and trauma units across Austria within a one-year period (January 2021 to December 2021) was retrieved from a government-maintained database. The absolute and relative frequencies of unplanned readmissions were calculated. Risk factors for 30-day and one-year readmission following THA or TKA due to implant-associated complications were investigated. ResultsThe thirty-day and one-year readmission rates for any implant-associated complication were 1.0% (339 of 34,392) and 3.0% (1,024 of 34,392). Relative to the overall readmission rate for any complication at 30 days (n = 1,952) and one year (n = 12,109), respectively, readmission rates for implant-associated complications were 17.4 and 8.5%. The thirty-day readmission rates were higher in THA (1.2%) than TKA patients (0.8%; P = 0.001), while it was the opposite at one year (THA, 2.7%; TKA, 3.3%; P < 0.001). Mechanical complications (554 of 1,024) were the most common reason for one-year readmission. Prolonged length of in-hospital stay independently associated with increased one-year readmission risk in THA and TKA patients. Treatment at large-sized hospitals was associated with a higher one-year readmission risk in TKA patients. ConclusionsThe thirty-day and one-year readmission rates for implant-associated complications following THA or TKA in Austria are lower than reported in other countries, with similar risk factors and reasons for readmission. Considering that almost 20% of unplanned hospital readmissions following total joint arthroplasty are attributable to implant-associated complications, optimization of in-hospital and post-discharge medical care for these patients is warranted.

Efficacy and outcomes of rescue screws in unstable pelvic ring injuries - A retrospective matched cohort study.

The emergency treatment of unstable pelvic ring injuries is still a challenge and requires surgical and anesthesiological resuscitation. Emergency fixation of the unstable pelvic ring with percutaneous sacroiliac (SI) screws, also known as "Rescue Screws", is an established treatment method. The aim of our study was to compare the outcome and complication rates of "Rescue Screws" with elective SI-screw fixations. A 1:1 ratio nearest-neighbor matched, retrospective cohort study of trauma patients with acute pelvic ring injuries at a level one trauma center was performed. Patients ≥ 15 years, treated with SI-screw fixation were included. pathologic fractures, missing consent and navigated procedures. The primary outcome parameters was defined as SI-screw revision operations. Patients were stratified according to treatment strategy (RS: Rescue Screws; EL: elective SI-screws). From 392 patients identified between 11/2014 and 08/2021, 186 met the inclusion criteria with 41 in the RS Group and 145 in the EL group. After matching, 41 patients were included in each group with similar baseline characteristics except persistent hemodynamic shock (RS: n = 22 (53.37%) vs. EL: n = 1 (4.3%), p < 0.001). Surgical characteristics were comparable in terms of instrumentation levels and insertion-sites. No significant differences were observed in the outcome parameters (revisions, reoperations, implant-associated complications, LOS and mortality) between both groups. Treatment of unstable pelvic ring fractures with Rescue Screws appears as a feasible treatment option for emergency stabilization. Rescue Screws are not associated with elevated revision rates and increased complications rates. This minimally invasive technique enables safe emergency stabilization of the posterior pelvic ring. Prospective or randomized clinical trials are required to directly compare Rescue Screws with other competing emergency stabilization techniques.

Risk of thromboembolism after intraosseous implantation of metallic devices with extracellular vesicles derived from multipotent stromal cells: preliminary results

Background. New implantation methods are of great importance due to the development of endoprostheses in traumatology and orthopedics, restorative medicine and dentistry. Equally important is the early detection and description of the implant-associated complications. The aim of the study is to find and describe thrombi and emboli in the heart and lungs formed after experimental implantation of metallic devices in the peripheral part of limb using extracellular vesicles of mesenchymal stromal cells. Methods. Outbred rabbits of both genders at the age from 4 to 6 months and of weight from 3 to 4 kg underwent experimental implantation. The study enrolled 57 species in total. They were divided into two groups: 30 animals underwent implantation of metallic devices using extracellular vesicles of mesenchymal stromal cells (EV MSCs), 27 — without their use. The rabbits’ hearts and lungs were studied by light microscopy methods at different stages after integration of screw titanium implants into the proximal condyle of the tibia using EV MSCs. Results. After implantation of metallic devices into the proximal condyle of the tibia, we detected fibrin, detritus and even the red bone marrow structures (various blast forms of hematopoietic cells: megakaryocytes, cells of the erythroid and myeloid lineages) in the right cavities of the heart. In the pulmonary arteries, we also found thrombi and emboli, which either led to the obliteration of the involved vessel or to gradual lysis, not disappearing completely within 10 days of follow-up. Conclusions. After intraosseous implantation of the metallic devices, there is an embolism risk in the right atria and ventricle of the heart and the pulmonary arteries and veins due to the debris migration with the bloodstream from the surgery site. At the same time, one cannot exclude a thrombotic risk in the heart and pulmonary arteries as a reaction to the presence of detritus. It is advisable to take measures aimed at preventing both debris releasing into the bloodstream and pulmonary embolism during any implantations into the bone tissues, even of relatively small devices. Using EV MSCs to affect the implant engraftment processes has no significant effect on the severity and frequency of thromboembolic complications.

Long-Term Outcomes of Enucleation and Secondary Orbital Implantation Surgeries Using Polyester Mesh-Wrapped Acrylic Orbital Implants.

To reveal the long-term outcomes of enucleation and secondary orbital implantation surgeries employing nonabsorbable surgical mesh-wrapped acrylic orbital implants for various reasons. A retrospective interventional study of 48 eyes that underwent primary or late primary enucleation and secondary orbital implantation using polyester mesh-wrapped acrylic orbital implants, between 2012 and 2021. Patient demographics, diagnosis, prior ophthalmic surgery, implant size, follow-up periods, and implant-associated complications were evaluated. The records of 36 patients who underwent primary or late primary enucleation and 12 who underwent secondary orbital implantation due to sphere extrusion were evaluated. Patients' mean age was 38.7 (range: 2-75) and the mean follow-up period was 48.3 months (range: 24-72mo). Major causes for surgeries were trauma and malignancies (54.1% and 33.3%, respectively). No complications, such as conjunctival dehiscence, implant exposure or extrusion, contracted socket, or fornix insufficiency were observed in any patient during the long-term follow-up period postsurgeries. Using polyester mesh-wrapped acrylic orbital implants in enucleation and secondary orbital implantation surgeries proves to be a successful, safe, and cost-effective option.

Inverted-bearing reverse shoulder arthroplasty: long-term survivorship, complications, clinical, and radiological outcomes

Inverted-bearing reverse shoulder arthroplasty (IB-RSA) is characterized by a polyethylene glenosphere and a metallic humeral liner to minimize polyethylene wear and debris secondary to impingement between the humerus and glenoid neck. IB-RSA long-term survivorship, complication and revision rates, as well as clinical and radiographic outcomes have not been reported yet. This is a monocentric retrospective study on a consecutive series of 151 patients who underwent primary IB-RSA from January 2009 to September 2015 and were evaluated clinically and radiologically at the minimum 8-year follow-up. All complications and reoperations were recorded. Survivorship analysis with any revision surgery as endpoint was done using Kaplan-Meier survival curves. Seventy-eight patients (follow-up rate 51.7%) were reviewed at a mean follow-up of 10.1±1.9years. At 10years, the revision-free survival was 98.7% (95% confidence interval: 94.8-99.7). Sixteen complications (10.6%) were observed: 2 axillary nerve injuries, 2 infections, 2 glenoid loosening (which stabilized within 1 year), 2 cases of otherwise unexplained painful stiffness, 4 acromial fractures, 1 post-traumatic scapular pillar fracture, and 3 post-traumatic humeral periprosthetic fractures. Two patients were revised due to infection. No cases of late glenoid loosening and humeral loosening were observed. The revision rate was 1.3%. All the clinical scores and range of motion significantly improved at the last follow-up compared with preoperative status: final Constant score was 66.1±17.4, Subjective Shoulder Value 79.1±20.9, and the American Shoulder and Elbow Surgeons 82.2±17.7. Scapular notching was observed in 51.4% of patients: only 1 case of grade 3 notching was observed in an early glenoid subsidence case. Primary IB-RSA appears to be a safe and effective procedure and does not present specific implant-associated complications at long-term follow-up. Radiographic analysis showed that inverting the biomaterials leads to a distinct kind of notching with mainly mechanical features.

Mid-term results of a cementless hip stem in femoral revision: how much diaphyseal press-fit do we need?

The aim of this retrospective study was to analyze the clinical and functional outcome of a modular tapered revision hip stem after mid-term follow-up with a special focus on the length of the distal bicortical fixation of the cementless hip stem. Follow-up examination was carried out for all patients with implantation of the Prevision hip stem between 2014 and 2019 to collect demographic, functional, and radiographic data. 44 patients with stem in situ were examined, and 61 patients could be included in the Kaplan-Meier survival analysis. Oxford's hip score was 37.3 at the mean follow-up of 4.0years. Two hip stem revisions were performed due to periprosthetic infection, which resulted in a hip stem survival rate of 96.7% (CI: 87.4-99.1%) at the final follow-up of 7.5years. No aseptic hip stem revision was required. The length of bicortical distal fixation was in the interquartile range of 6.8 to 9.0cm, which was associated with good bone healing and a low rate of subsidence (4.5%). Implant-associated complications were observed in 10 cases (21.7%). The modular revision hip stem provides promising results at medium-term follow-up, with satisfactory clinical and functional outcomes comparable to other modular revision hip stems. The presented length of bicortical distal fixation shows the practice of the study center and was associated with good implant survival, bone healing and radiological results. Clinicaltrials.gov registration: NCT04833634 registered on April 6, 2021.

Rethinking risk prediction: The role of albumin and other parameters in implant-associated complications after hip or knee arthroplasty.

Total hip (THA) or knee (TKA) arthroplasty is still a traumatic and challenging operation that induces inflammation, with a particularly high risk of acute-phase reaction. The aim of this study was to predict the likelihood of implant-associated complications during the preoperative and postoperative course. The prospective observational, non-interventional study of patients diagnosed with primary knee or hip osteoarthrosis undergoing THA or TKA during the study period was conducted. The inflammatory and malnutrition parameters were collected for each patient one day before surgery, two days after surgery, and in outpatient follow-up. Of 159 patients analysed, 12 developed implant-associated complications. The albumin, prealbumin, Intensive Care Infection Score (ICIS), Nutritional Risk Index, and white blood cell counts were found to be potential predictors. Notably, preoperative albumin levels significantly differed between groups with and without complications (P-value = 0.042). Our study definitively shows that WBC, prealbumin, Nutritional Risk Index, ICIS as a novel marker, and significantly albumin, outperform C-reactive protein in predicting implant-associated complications in hip and knee arthroplasty.

Promontofixation Using Titanium Mesh Implant in a Patient with Genital Prolapse: A Clinical Case

Introduction. Pelvic organ prolapse is increasingly spreading around the world. Therefore, surgical interventions in this pathology are becoming more frequent. Non-mesh surgery for pelvic organ prolapse is reported to have a higher incidence of disease recurrence, and polypropylene mesh implants appear to cause implant-associated complications, thereby limiting their application in clinical practice. Materials and methods. When a patient with an apical prolapse and high risk of postoperative complications sought medical care in the Clinic, the specialists decided to perform promontofixation using a titanium mesh implant. Results and discussion. The present paper describes a clinical case of surgical treatment of genital prolapse using a titanium mesh implant. Since the patient who was admitted for surgical treatment had a family history of genital prolapse, an application of non-mesh technologies implied a high probability of genital prolapse recurrence, as well as a high risk of the vaginal erosion after surgery. Therefore, a promontofixation was performed using a titanium mesh implant, and the 6-month follow-up period showed no postoperative complications. Conclusion. Analysis of postoperative complications demonstrated a considerable potential of using titanium mesh implants for the prevention of implant-associated complications.

Influence of exposure of customized dental implant abutments to different cleaning procedures: an in vitro study using AI-assisted SEM/EDS analysis

PurposeDental implant abutments are defined as medical devices by their intended use. Surfaces of custom-made CAD/CAM two-piece abutments may become contaminated during the manufacturing process in the dental lab. Inadequate reprocessing prior to patient care may contribute to implant-associated complications. Risk-adapted hygiene management is required to meet the requirements for medical devices.MethodsA total of 49 CAD/CAM-manufactured zirconia copings were bonded to prefabricated titanium bases. One group was bonded, polished, and cleaned separately in dental laboratories throughout Germany (LA). Another group was left untreated (NC). Five groups received the following hygiene regimen: three-stage ultrasonic cleaning (CP and FP), steam (SC), argon–oxygen plasma (PL), and simple ultrasonic cleaning (UD). Contaminants were detected using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) and segmented and quantified using interactive machine learning (ML) and thresholding (SW). The data were statistically analysed using non-parametric tests (Kruskal–Wallis test, Dunn’s test).ResultsSignificant differences in contamination levels with the different cleaning procedures were found (p ≤ 0.01). The FP–NC/LA groups showed the most significant difference in contamination levels for both measurement methods (ML, SW), followed by CP–LA/NC and UD–LA/NC for SW and CP–LA/NC and PL–LA/NC for ML (p ≤ 0.05). EDS revealed organic contamination in all specimens; traces of aluminum, silicon, and calcium were detected.ConclusionsChemothermal cleaning methods based on ultrasound and argon–oxygen plasma effectively removed process-related contamination from zirconia surfaces. Machine learning is a promising assessment tool for quantifying and monitoring external contamination on zirconia abutments.Graphical

Tibial Bone Transport with a Single Implant All-Internal Bone Transport Nail.

A single implant all-internal magnet-driven bone transport (BT) intramedullary nail (BTN - NuVasive Specialized Orthopaedics, Inc.) has recently been introduced as a treatment method for segmental tibial bone defects. This innovation provides promise in the management of segmental bone defects as it negates numerous complications associated with circular external fixation and the need for multiple implants when considering hybrid plate assisted bone segment transport (PABST) constructs. Given the novelty of the BTN, description of the surgical application and patient outcome measures are scarce in the current literature. To date, we have treated four patients with an average age of 27 years (range: 19-44 years) using the BTN for segmental tibial defects ranging from 50-128 mm. We have accumulated data over an average follow up of 18.07 months (range: 12.96-25.13 months) demonstrating good patient tolerance of the device. Three patients successfully completed their treatment course with a calculated average bone healing index of 41.4 days/cm (range: 31.41-54.82 days/cm). One patient was noted to experience an asymptomatic docking site nonunion requiring subsequent surgery for nonunion repair. Implant-associated complications included symptomatic implant, axial malalignment, docking site nonunion, and External Remote Control technical malfunction. Injury-related complications were encountered and noted to include: superficial infection, wound dehiscence, peroneal tendonitis, and joint rigidity. In this study, the authors present a case series utilizing this implant to date and discuss our experiences with the BTN with reference to clinical indications, tibial bone preparation, BTN implantation, transport protocol, docking site procedure, and clinical/radiographic outcomes.

OC-073 THE 3-D FUNNEL MESH TECHNIQUE FOR PARASTOMAL HERNIA REPAIR

Abstract Background In previous studies, three-dimensional funnel mesh devices have been used successfully for the repair of PSHs by combining a laparoscopic and ostomy-opening approach Methods We performed an analysis of prospectively collected data of patients who underwent a same-sided stoma reposition with 3D funnel-shaped mesh augmentation in intraperitoneal- onlay position at three departments between the years of 2012 and 2021. 56 patients received an implant with 2.5 cm funnel length and 25 patients with 4cm funnel length. Primary outcome parameters were surgical complications and recurrence rate. Results 81 patients could be included in this analysis. PSH repair was performed in 91% as elective surgery and in 87% in laparoscopic technique. A concomitant incisional hernia (EHS type 2 and 4) was found in 39% and repaired in a single-step procedure with PSH. Major postoperative complications requiring redo surgery were identified in 9.8% (8/81). Overall recurrence rate was 11% (9/81). Only 1 recurrence occurred in the group of 4 cm long implants (1/25= 4%). Median follow-up time was 44 months, and a 1-year follow-up rate of 91.4% was reached. Conclusion PSH repair with 3D funnel mesh in IPOM technique is safe, efficient and easy to perform providing advantageous results compared to other techniques. However the origin mesh funnel (2.5cm length) becomes shortened over time and further shrinkage happens eccentric concerning the flat mesh parts widening the funnel. Changing mesh construction according to consequently use the narrowest funnel (2cm) and it`s lengthening to 4cm led to reduction in recurrence without increasing implant-associated complications

Clinical and Radiological Outcome of Disc Arthroplasty for the Treatment of Cervical Spondylotic Myelopathy.

The aim of this study is to evaluate the clinical and radiological results of cervical disc arthroplasty (CDA) in patients with cervical spondylotic myelopathy (CSM) using the CP ESP® disc prosthesis. Prospectively collected data of 56 patients with CSM have been analyzed. The mean age at surgery was 35.6 years (range: 25-43 years). The mean follow-up was 28.2 months (range: 13-42 months). The range of motion (ROM) of the index segments, as well as upper and lower adjacent segments, was measured before surgery and at final follow-up. The C2-C7 sagittal vertical axis (SVA), C2-C7 cervical lordosis (CL), and T1 slope minus cervical lordosis (T1s-CL) were analyzed as well. Pain intensity was measured preoperatively and during follow-up using an 11-point numeric rating scale (NRS). Modified Japanese Orthopaedic Association (mJOA) score was assessed preoperatively and during follow-up for the clinical assessment of myelopathy. Surgical and implant-associated complications were analyzed as well. The NRS pain score improved from a mean of 7.4 (±1.1) preoperatively to a mean of 1.5 (±0.7) at last follow-up (p < 0.001). The mJOA score improved from a mean of 13.1 (±2.8) preoperatively to a mean of 14.8 (±2.3) at last follow-up (p < 0.001). The mean ROM of the index levels increased from 5.2° (±3.0) preoperatively to 7.3° (±3.2) at last follow-up (p < 0.05). Four patients developed heterotopic ossifications during follow-up. One patient developed permanent dysphonia. CDA showed good clinical and radiological outcome in this cohort of young patients. The motion of index segments could be preserved. CDA may be a viable treatment option in selected patients with CSM.

Fixation techniques in periacetabular osteotomy : Stability and clinical aspects of established and new fixation techniques

Periacetabular osteotomy according to Ganz (PAO) is an established technique for the surgical treatment of hip dysplasia with the aim of biomechanically optimizing the dysplastic hip joint. Through multidimensional reorientation, the deficient coverage of the femoral head can be improved and physiological values can be achieved. Until bony consolidation is reached, adequate fixation of the acetabulum in the corrected position achieved is necessary. Various fixation techniques are available for this purpose. Alternatively to screws, Kirschner wires can also be used for fixation. The different fixation techniques show comparable stability. Differences exist in the occurrence of implant-associated complications. However, there is no difference in patient satisfaction and joint-specific function.

Guided growth: angular deformity correction through temporary hemiepiphysiodesis with a novel flexible staple (FlexTack)

Temporary hemiepiphysiodesis (HED) is applied to children and adolescents to correct angular deformities (ADs) in long bones through guided growth. Traditional Blount staples or two-hole plates are mainly used for this indication. Despite precise surgical techniques and attentive postoperative follow-up, implant-associated complications are frequently described. To address these pitfalls, a flexible staple was developed to combine the advantages of the established implants. This study provides the first results of guided growth using the new implant and compares these with the established two-hole plates and Blount staples. Between January 2013 and December 2016, 138 patients (22 children, 116 adolescents) with genu valgum or genu varum were treated with 285 flexible staples. The minimum follow-up was 24 months. These results were compared with 98 patients treated with 205 two-hole plates and 92 patients treated with 535 Blount staples. In long-standing anteroposterior radiographs, mechanical axis deviations (MADs) were measured before and during treatment to analyze treatment efficiency. The evaluation of the new flexible staple was performed according to the idea, development, evaluation, assessment, long-term (IDEAL) study framework (Stage 2a). Overall, 79% (109/138) of patients treated with flexible staples achieved sufficient deformity correction. The median treatment duration was 16 months (interquartile range (IQR) 8 to 21). The flexible staples achieved a median MAD correction of 1.2 mm/month/HED site (IQR 0.6 to 2.0) in valgus deformities and 0.6 mm/month/HED site (IQR 0.2 to 1.5) in varus deformities. Wound infections occurred in 1%, haematomas and joint effusions in 4%, and implant-associated complications in 1% of patients treated with flexible staples. Valgus AD were corrected faster using flexible staples than two-hole plates and Blount staples. Furthermore, the median MAD after treatment was lower in varus and valgus AD, fewer implant-associated complications were detected, and reduced implantation times were recorded using flexible staples. The flexible staple seems to be a viable option for guided growth, showing comparable or possibly better results regarding correction speed and reducing implant-associated complications. Further comparative studies are required to substantiate these findings.

Implantatassoziierte Komplikationen in der Hüftendoprothetik: Biologische Reaktionen des „Microenvironments“ auf das Implantat

Implantatassoziierte Komplikationen in der Hüftendoprothetik: Biologische Reaktionen des „Microenvironments“ auf das Implantat

Demographics and Etiology for Lower Extremity Amputations-Experiences of an University Orthopaedic Center in Germany.

Background and Objectives: Currently, the worldwide incidence of major amputations in the general population is decreasing whereas the incidence of minor amputations is increasing. The purpose of our study was to analyze whether this trend is reflected among orthopaedic patients treated with lower extremity amputation in our orthopaedic university institution. Materials and Methods: We conducted a single-center retrospective study and included patients referred to our orthopaedic department for lower extremity amputation (LEA) between January 2007 and December 2019. Acquired data were the year of amputation, age, sex, level of amputation and cause of amputation. T test and Chi² test were performed to compare age and amputation rates between males and females; significance was defined as p < 0.05. Linear regression and multivariate logistic regression models were used to test time trends and to calculate probabilities for LEA. Results: A total of 114 amputations of the lower extremity were performed, of which 60.5% were major amputations. The number of major amputations increased over time with a rate of 0.6 amputation/year. Men were significantly more often affected by LEA than women. Age of LEA for men was significantly below the age of LEA for women (men: 54.8 ± 2.8 years, women: 64.9 ± 3.2 years, p = 0.021). Main causes leading to LEA were tumors (28.9%) and implant-associated complications (25.4%). Implant-associated complications and age raised the probability for major amputation, whereas malformation, angiopathies and infections were more likely to cause a minor amputation. Conclusions: Among patients in our orthopaedic institution, etiology of amputations of the lower extremity is multifactorial and differs from other surgical specialties. The number of major amputations has increased continuously over the past years. Age and sex, as well as diagnosis, influence the type and level of amputation.

Cross-pin stabilisation of a distal femoral physeal fracture in a miniature Rex rabbit

This case report details the presentation, treatment and medium-term follow up for a distal femoral physeal fracture in a miniature Rex rabbit. A 5-month-old rabbit presented with right hindlimb lameness after attempting to escape and becoming entangled in a cage. On examination, instability affecting the distal right femur was noted, and radiographs revealed a Salter-Harris type I fracture. Open reduction and internal fixation was performed under general anaesthesia using four 0.7 mm cross pins. Satisfactory clinical and radiographic progress was noted 3 weeks postoperatively. At postoperative follow up 6 weeks later, lameness was mild and by 12 weeks the lameness had resolved. Radiographs taken 12 weeks postoperatively revealed that alignment, apposition and implant placement had been maintained and there was no evidence of implant-associated complications. Clinical union had been achieved. Remote follow up with the owners 7 months postoperatively revealed that the rabbit had returned to normal activity levels and experienced no adverse sequelae following the fracture's repair. The satisfactory medium-term outcomes seen after cross-pin placement indicate that this may be an appropriate repair method for distal femoral Salter-Harris type I fractures in rabbits. To the authors’ knowledge, this is the first succesful cross-pin stabilisation of a Salter-Harris type I fracture in a rabbit of this age.

Transcutaneous versus percutaneous bone-anchored hearing aids: A quality of life comparison

PurposeTo determine whether patients have improved quality of life outcomes with percutaneous bone conduction implant (p-BCI) versus transcutaneous bone conduction implant (t-BCI). Materials & methodsRetrospective chart review of patients who have undergone placement of a BCI in the Ascension St John Providence Health System from 2013 to 2018. Patient satisfaction of t-BCI and p-BCI was measured using a questionnaire that incorporated the Glasgow Benefit Inventory (GBI) and BAHA, aesthetic, hygiene & use (BAHU) survey. Key outcome variables were separated into 2 categories: (1) evaluation of wound healing and implant-associated complications, and (2) quality of life improvements. ResultsComparative analysis of the 27 p-BCI patients and 10 t-BCI patients showed overall positive benefit with no statistically significant difference on quality of life improvement between the two groups. Total complication rates for p-BCI (48.1 %) vs t-BCI (10 %) was marginally significant (p = 0.056). Rate of revision for p-BCI versus t-BCI was 14.8 % vs 0 %, respectively. ConclusionThis study provides a much-needed comparative insight in patient's experience with these two devices. Understanding which device is preferable in the patient's view will offer helpful information for guiding proper implant selection.

Laser Microperforation Assisted Drug-Elution from Biodegradable Films.

In a modern high-tech medicine, drug-eluting polymer coatings are actively used to solve a wide range of problems, including the prevention of post-surgery infection, inflammatory, restenosis, thrombosis and many other implant-associated complications. For major assumptions, the drug elution mechanism is considered mainly to be driven by the degradation of the polymer matrix. This process is very environmentally dependent, unpredictable and often leads to a non-linear drug release kinetic. In the present work, we demonstrate how the laser microperforation of cargo-loaded biodegradable films could be used as a tool to achieve zero-order release kinetics with different elution rates. The effects of the laser-induced hole’s diameter (10, 18, 22, 24 µm) and their density (0, 1, 2, 4 per sample) on release kinetic are studied. The linear dynamics of elution was measured for all perforation densities. Release rates were estimated to be 0.018 ± 0.01 µg/day, 0.211 ± 0.08 µg/day, 0.681 ± 0.1 µg/day and 1.19 ± 0.12 µg/day for groups with 0, 1, 2, 4 microperforations, respectively. The role of biodegradation of the polymer matrix is reduced only to the decomposition of the film over time with no major influence on elution rates.