Brachymetatarsia is the more than 5 mm shortening of the metatarsal parabolic arc of the foot, in one or more metatarsals. In our presentation we will explore the definition, the etiology, the surgical treatment options and the achieved results will be introduced. This case report will cover two congenital, uni- and bilateral brachymetatarsias that affected 2 and 3 metatarsals. Furthermore, we will discuss potential risks and complications that can occur during or following such surgeries. In order to lengthen the metatarsal bones, a mini-external fixator was used. Callotatis, a technique of callus distraction was utilized during the elongation procedure. Two external fixators were used for the metatarsal bone lengthening procedure, for both patients. The three metatarsal bones were elongated concurrently by an external fixator placed on the third and fifth metatarsal bones and the elongation of the fourth metatarsal was achieved by stapling the metatarsal heads together. Following the 8 weeks elongation procedure and the bony healing, MTP release and temporer desis had to be performed in order to correct the subluxatio in the MTP joint. As a result of the elongation procedure, the desired length was achieved, appropriate regenerate bone fully consolidated and following the release of the MTP joint capsules the appropriate position of the toes was re-established. By applying the AOFAS outcome measure assessment, it can be concluded that a significant improvement in the condition of the patients was achieved. This surgical treatment is suitable for simultaneous stretching of more than one shortened metatarsal.

Introduction: The prevalence of scoliosis is high in spinal muscular atrophy (SMA). As the natural history of the condition has changed due to recently approved treatments, most severe SMA I type patients may survive and the risk for developing scoliosis is increasing. The aim of our study was to evaluate the spinal deformity in SMA and to find correlation between spinal deformity and age and also number of smn2 gene copies.
Methods: 24 SMA patients (mean age: 10,1 years, SD: 5,3) were examined. The number of smn2 gene copies data were collected from genetic reports. Cobb angles were measured on antero-posterior spinal x-ray images to determine the severity of scoliosis. Correlation coefficient was calculated for statistical analysis.
Results: Patients with 2 or 3 copies of smn2 gene showed no difference in Cobb angle, while patients with 4 copies developed remarkably milder deformity. Only one patient presented scoliosis not greater than 10 degrees, however this was accompanied by severe sagittal plane deformity. The severity of scoliosis was found to be strongly related to the age of the patients in SMA I and II. Such relationship cannot be established in the SMA III group.
Significance: Life expectancy and quality of life were increased by current treatments of SMA. Severe cases can be better rehabilitated, increasing the the risk of long term deformities. Authors believe that scoliosis develops eventually in nearly all cases of SMA, therefore the necessity of bracing should be considered in all patients right after upright position (seating) is achieved.

Aims: The results of 772 Exeter cemented total hip arthroplasties are presented with a minimum of 10-year follow-up. Patients and methods: A period between January 2000 and December 2009 has been reviewed. Regardless of the indication diagnosis, all patients received the Exeter Universal stem until April 2006, afterwards the Exeter V40 stem was used. Cemented Exeter low profile cups were used in the vast majority of the patients. Results: 895 total hip replacements were done with the Exeter system during the above period. A total of 104 patients died before the ten year follow-up date, all of them had their prosthesis in place at the time of death. 123 additional patients were lost to follow-up for any other reason. A total of 772 hips were available for review. The mean follow-up time of the surviving hips was 13.63 years (10-19.5). A total of 675 (87.4%) prostheses were in place at the time of the last follow-up or at the time of death. All together 47 (6.1%) revisions were done for aseptic loosening of any of the components (34 acetabular, 5 stem, 8 acetabular+stem). 31 (4%) septic complications and 19 (2.5%) periprosthetic fractures occurred. Conclusions: The low rate of aseptic loosening of the Exeter Universal and V40 stems prove the excellent performance of this system in a wide range of patients with different diagnosis of indication. The performance of the cemented Exeter low profile cups are inferior to that of the stems, however, it still can be considered a good result.

In September 2012 we introduced the Minimally Invasive AC Joint Reconstruction (MINAR) technique in our institute. Our aim was to conduct a retrospective study of 87 operations performed before 2020. All patients were asked to come back for a follow-up for this retrospective study. The X-rays then were repeated on their operation sites and in their assessment the Constant and DASH scores were applied. Eventually we managed to recruit 43 patients (48%) for the study of their midterm outcomes. The male to female ratio was 9.75 (4f/39m), with a mean age of 43.7 years. The mean follow-up time was 31.6 months (range: 6-63 months). According to the Rockwood classification 23 (54%) grade-III lesions, 1 (2%) grade-IV lesion and 19 (44%) grade-V lesions were found. The overall mean clinical outcome was: Constant score: 92.9, DASH score: 4.25. 77% was graded ’excellent’, 21% ’good’ and 2% ’fair’ using the Constant Score. 85% was classified ’excellent’, 9% ’good’ and 6% ’fair’ based on the DASH score. We can conclude that surgical fixation of acute AC joint dislocations with the MINAR technique results in good-to-excellent functional outcomes and proves highly satisfactory for the majority of patients. Importantly the technique is relatively easy to master with no need to specialist training in shoulder or arthroscopic surgery, hence it can be used more widely without referral to specialist centres and perhaps reducing waiting times

In 2017 the number of road deaths per million inhabitants was 64 in Hungary. Although the number of victims decreased by ten in the previous seven years, the rate of mortality is still 8th in the EU. Data were collected from the Hungarian Central Statistical Office, the Police, the National Ambulance Service, and the Professional Disaster Relief Organization (Fire Department). Between 01.01.2015 and 31.12.2019, 83025 accidents were registered in Hungary. Casualties decreased from 585 to 530 during these years, but the number of minor injuries increased. People have better cars, seat belts are used more frequently, and car seats for babies are mandatory. Fewer accidents are caused by drunken drivers. Accident frequency is higher in Budapest and surroundings, and on transit roads closer to the border. Accidents were caused by car drivers in 53220, bicycle riders in 8585, truckdrivers in 7686, motorcyclists in 3311, moped riders in 3147 cases. Pedestrians were at fault in 4639 cases. Driving over the speed limit was found in only 991 accidents, but 25004 drivers did not drive according to road conditions. 5315 fouled in overtaking. Irregular changeover and turning caused collisions in 28887 cases. Priority was not given in 28318 accidents. Vehicular technical hitches were verified in only 488 events. Fire fighters rescue entrapped persons and prevent electric fires. Severely injured patients are transported to trauma centers by the Ambulance Service. Trauma care is well organized in Hungary, but the first goal is prevention.

Introduction
Appropriate acetabular cup orientation is an important factor in reducing instability and maximising the performance of the bearing after Total Hip Arthroplasty (THA). Due to the large variation in patient kinematics between functional activities, current technologies lack definition of what constitutes correct target alignment. Acetabular cup orientations placed within Lewinnek’s proposed safe zone can dislocate due to functional component malalignment. Ideal acetabular cup orientation requires a more advanced analysis accounting for individual variation in functional positions.

Method
Pre-operatively 160 consecutive total hip replacement patients underwent acetabular planning utilizing a pre-operative CT scan and functional imaging. As part of the planning, radiographic parameters including inclination, anteversion, functional pelvic tilt, pelvic incidence and lumbar flexion were analysed. Using these inputs, the software proposes an optimal cup orientation for each patient. Retrospectively the software proposed cup orientation was compared to the Lewinnek safe zone.

Results
Mean age of patients was 59 years (29 to 82). Mean planned cup inclination in reference to the anterior pelvic plane (APP) was 42° (33° to 49°) and mean planned cup anteversion, referenced to the APP, was 26° (11° to 43°). Only 44% of cups planned with functional imaging were within the Lewinnek safe zone for both inclination (40°±10°) and anteversion (15°±10°) (Fig 1).

Conclusion
Historical target parameters for cup inclination and anteversion significantly differ from target values obtained with the use of functional imaging. Understanding the individual spinopelvic mobility allows for the creation of a functional and patient-specific target for acetabular component orientation.

Background: Primary stiff shoulder is a common medical condition often necessitating medical treatment. The ideal therapeutic method is yet to be determined.

Aim: Analyzing the effect of different treatment options used for the management of primary stiff shoulder.

Method: Fifty nine patients were evaluated, their demographic data, physical examination, concomitant diseases and treatment specific data were registered. Life quality and the level of pain was assessed using the Oxford Shoulder Score (OSS) and Numeric Pain Rating Scale (NPRS). Different treatment modalities and their effect on life quality, pain relief and the length of the disease were recorded. Any existing correlation between these variables was investigated.

Results: The level of pain improved from 7,9±1,6 to 1,9±2,2. Although half of the patients reported slight pain at the end of the treatment, 76 % were satisfied. The most effective therapeutic method in terms of pain relief was surgery, followed by physiotherapy and intraarticular steroid injection (NPRS score after treatment: 2 - p<0.0001; 3,3 - p<0,0001; 4,9 - p<0,000, respectively). Non-steroidal anti-inflammatory drugs provided temporary improvement solely. OSS improved from 24 to 43,6 and was not affected by the investigated variables.

Conclusion: Despite the persistent pain found in half of our patients, treatment was considered satisfactory in most cases. Both surgical and conservative therapy proved to be effective, while NSAIDs provided only temporary improvement. Nor patient specific data neither therapy specific data had a significant effect on the course of the disease.

Hip arthroplasty in presence of excessive periacetabular bone loss (over Paprosky 2B) or following tumor resection may be challenging on the pelvic side. In several cases we can save the use of custom-made implants with the use of off-shelf ice-cone shaped acetabular implants. However, these cups intended originally for primary arthroplasty, in those cases PSI instrumentation is required. We developed our own 3D printing-based technique to support the positioning. During the last 3 years we applied and improved our technique and arrived to a reliable, easy-to-use PSI, not needing any special navigation system to help a secure and precise placement. We are reporting on the evolution and the actual design of our concept.

Introduction: Periprosthetic fractures (PPFx) occur more and more often following joint replacement. The aim of this study was to investigate the functional outcome of patients treated with lower limb periprosthetic fractures in our institution.
Methods: Between 2007 and 2016 75 patients were managed with 13 intraoperative and 62 postoperative fractures. Fifty-nine fractures occurred around THR and 16 around TKR. Fractures were classified according to Unified Classification System (UCS) and the treatment was according to this algorithm. Functional outcome was assessed with the Harris Hip Scores and the Knee Society Score (KSS).
Results: Follow up time was 52.9 months (range 12-100 m.). The mean age of patients was 75.1 years (range 54–87 years), there were 6 males and 69 females. Harris Hip Scores were available for 42 patients and the average score was 82 (range 68-96). The KSS was available in nine patients and the average score was 124 (range 102-141). Eventually, radiographic union was observed in all cases.
Conclusion: In this series of patients, fixation of lower limb periprosthetic fractures was found to be associated with good results despite the different fracture patterns studied. Larger studies with subgroup analysis of different fracture patterns are desirable to throw more light in this complex group of patients.

INTRODUCTION: The neck-shaft or collodiaphyseal angle is one of the most important radiological parameter to evaluate the pediatric hip. The complexity of the proximal femur causes projectional distortion on conventional radiographs making the measurement inaccurate. The aim of our study to examine the reliability of the widely used conventional neck-shaft angle measuring methods.
METHODS: 90 (45 girls-45 boys, 4-16 year-old) patients’ EOS images were selected retrospectively from our database. All of the imaging studies were performed due to joint paint with unknown origin, and no pathological deformity were revealed. Using the 2D conventional modality of the EOS images the neck-shaft angle was measured using the “biggest-diameter” and the “circle-fitting” method. EOS 3D reconstructions of the femurs were also performed. For statistical analysis Student’s T-Test and Spearman correlation test were used.
RESULTS: Significant difference was found between the conventional 2D based methods’ and the EOS 3D reconstructions’ results („circle-fitting” method:132,94±5,31°, „biggest diameter” method:133,76±5,56°, EOS 3D:130,22±5,00°, p<0,001). The absolute difference in the „circle-fitting” method was smaller (4,10±2,86° vs 4,41±3,09°, p=0,042). In the 30% of the cases the difference between the 2D and 3D measured results were more than 5°, in 6% more than 10°. The difference was influenced only by the femoral torsion from the 14 examined parameters (correlation coefficient:0,464, p<0,001).
CONCLUSIONS: The distortion caused by the femoral torsion results significantly higher neck-shaft angle measurement results using conventional 2D methods. In the 1/3 of cases this difference was more than 5°. The “circle-fitting” method proved to be slightly more accurate.

Background: Extracellular vesicles (EVs) are considered as crucial players in a wide variety of biological processes, however, much less is known about their function in periprosthetic joint infection (PJI). Our aim was to investigate activated polymorphonuclear (PMN) derived synovial EVs in patients with PJI.

Methods: Thirty-four patients (n=34) were enrolled into our investigation, 17 with PJI and 17 with aseptic prosthesis loosening. Periprosthetic joint fluid was aspirated and EVs were isolated. Samples were investigated by nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). EVs were analyzed after Annexin V and CD177 labelling by flow cytometry (FC). The protein content of the EVs was analyzed by mass spectrometry (MS).

Results: NTA showed particle size distribution in both groups between 150 nm and 450 nm. The concentration of EVs were significantly higher in the septic samples and showed a different size pattern. FC analyzis resulted a significantly increased event number both after single labelling with Annexin V and double dying with Annexin V and CD177 in the septic group. The vesicular nature of the measured particles was proven by TEM and differential detergent lysis. MS detected a significant difference in the concentration of lactotransferrin, myeloperoxidase, lysosyme C, annexin A6 and alpha-2-HS-glycoprotein between the studied groups.

Conclusions: An increased number of activated PMN derived EVs were detected in the synovial fluid of PJI patients with a characteristic size distribution and a specific protein content. The possible application of our results in the diagnostics of PJI should be the focus of further investigations.

Introduction: Defect and constraint algorythm focusing on Haider-Walker’s contemporary constraint is introduced. The least, appropriate constraint possible phylosophy was applied with main focus on the level of destruction.
Objectives: 2011 - 2020 847 patients were operated with difficult anatomy using revision TKA.
Diagnostic and therapeutic algorythm includes management of malalignment, rotation, defects, stability, exclusion of infection, always 3 step technique.
There was special focus on differential diagnosis, indication of RH and CC Knees.
Method: 219 more than 20 degree of varus & rotation, 91 more than 25 degree of valgus & rotation, 507 significant bone defect & instability are included. Implants used were appropriate constraint of NexGen system.
( 113 LPS, 504 CCK, 224 RHK, 6 segmental ) Average age was 69. KSKS was used for follow up. AORI score was used for defect analysis. Minimal box dephts, unilateral defect management is detailed.
Results: Using proper constraint excellent results were seen independent of constraint, defect and other difficulties using KSKS. Reconstruction of stability and balance was appropriate in 99.05%. Average KSKS was 173, function on 2nd postop day was 60° with reduced pain. Minor wound healing problems 7, postop infection 5. 3 inadequate constraint indicated re-revision.
Conclusion: In cases of difficult primary and revision TKA with significant bone loss reconstruction of primary anatomy is of significant importance using techniques of appropriate augmentation and most importantly constraint. Rotation instability acts as major indication criteria.

Chronic untreated synovitis leads to osteoarthritis in the affected joints. Since 2003, We performed more than 773 radiosynovectomies for the treatment of chronic synovitis at our orthopaedic department . About 15% of these procedures were ineffective. In this study we tried to find an explanation for this unfavourable outcome.

Objectives
To reveal the reasons for unsuccessful synovectomies in our patients.

Study Design & Methods
During in vivo surgical, arthroscopic synovectomies-following ineffective radiosynovectomies- we removed the inflamed synovia as a part of therapeutic algorithm and harvested biopsies for further histological and electron microscopic examinations. In total, 38 joints- 4 hips, 28 knees and 6 ankles were treated with surgical synovectomies. During the surgical procedures, 4 biopsies were obtained from each joint. Two out of 4 biopsies were sent for histological examinations and the other 2 biopsies were examined by electron microscope. All together 152 biopsies were evaluated.Mean age of the patients was 54 years.
The mean time between the arthroscopy and radiosynovectomy was 10 months (7-16).

Results
All histological examinations revealed persistent synovitis during the surgical synovectomies. Immunohistochemical studies revealed active macrophages with IL-6 and TNF-alfa production.Electron microscopic examinations showed the remnant of stable isotopes in the samples, but the isotope was not phagocytized by the synovial "A" type cells.

Conclusions
In the case of ineffective radiosynovectomies the isotopes were not phagocytized by the synovial A cells of the treated joints. Further examinations are planned to reveal the reasons for ineffective phagocytosis of the synovial A cells.

Introduction: Developmental dysplasia of the hip (DDH) is one of the most common causes of secondary osteoarthritis in early adulthood. The femoral head is partially or fully uncovered, the rotational center is displaced laterally and cranially. According to the literature the question of cup positioning during THR is still unresolved for many surgeons. In our belief we must do our best to restore the primary rotational center. Methods: When the supero-inferior acetabular diameter is higher than the sagittal one is, we are using our own technique, the so-called Roof Step Cut (RSC). The femoral head is used as an L-shaped graft onto the previously accordingly prepared proximal pole and secured with two screws and a double washer. This way we can achieve a full proximal cup covering allowing generally the use of an uncemented cup. Results: Between 2008-2019 we applied the RSC in 54 cases. Until now no complication of bone healing or implant loosening has occurred. To check the graft integration we followed the patients at the beginning of the technique by bone scintigraphy. The final graft and cup integration is estimated between 6 and 12 months. Conclusion: We are reporting our bone grafting technique for THA in dysplastic hips, which is based on a geometrically similar graft shaping easy to reproduce. We have got a 11-year follow-up with excellent outcome.

Introduction: Osteochondral defects of the weight bearing areas are challenging to treat. If conservative treatment is insufficient surgical reconstruction may be required. As a reconstruction option autologous structural bone transplantation in combination with hyaluronic acid scaffold implantation can be chosen for the treatment of large even uncontained osteochondral lesions of the femoral condyles. Methods: 4 patients with large osteochondral lesions were treated. The follow-up period is in all cases more than 3 years. 3 patients were treated for OCD of the medial femoral condyle 1 patient had an impressional fracture of the lateral femoral condyle. The average size of lesions was 4.5 cm2 (3-6 cm2), the mean condylar width was 37.95 mm (34.5-37.91 mm), and the median proportion (lesion size / condylar width) was 52.39% (43.48-62.97%). The average graft surface area was 4.5 cm2 (3-6 cm2). Results: The mean follow-up time was 48.75 months (38-60 months). None of the patients required further surgery. No graft incorporation problem was observed in either case. During follow-up, we used IKDC scores and the KOOS score. We constructed a subjective five-grade score (from dissatisfied to extremely satisfied).
The outcome scores of IKDC and KOOS improved compared with the preoperative. In the five-grade score all of our patients chose the „extremely satisfied” grade in their most recent follow-up study.
Radiological scans showed good graft integration and no bone graft fragmentation or subsidence was observed. Conclusion: Autologous bone transplantation combined with hyaluronic acid scaffold implantation appears to be an effective solution in this patient population.

Introduction: Incidence, functional influence and clinical relevance of limb length discrepancy (LLD) as well as the validity of the different assessing methods for its measurement is subject to discussion. Objective: Our prospective diagnostic study aimed to analyse the difference of the 2D radiological measurement of limb length discrepancy compared to a 3D method based on EOS 3D reconstructions. Materials and methods: 50 healthy volunteers (30 males, 20 females, aged between 21-26 years, mean age 23,58, without any orthopaedic complaint, major deformity, diseases or previous operation on lower extremity, mean BMI: 24) were involved and EOS imaging was performed. We measured the length of the lower limbs with conventional 2D technique and SterEOS 3D reconstruction. The results were compared with intra-class correlation test, and T-test. Results: The Student´s paired T-test with a p value of 0,47 in functional and 0,65 in anatomical discrepancy showed no statistically significant difference in between the two measuring methods. The ICC values turned out to be 0,920 in functional and 0,935 in anatomical assessment. Variation exceeding 5 mm or greater was detected in only 1 case (2%) of functional and in 2 cases (4%) of anatomical length in between the two measuring methods. Conclusions: Our investigation showed that in a young and healthy population it is not necessary to make a 3D reconstruction to evaluate the true leg length for clinical decision-making. Patient education prior the examination is very important to avoid inaccurate standing positions in the EOS (knee flexion, leg rotation) with consequential assessment errors.

It was our goal to seek for biomechanical differences between two types of sterilizing methods and different storage times in tendon allografts. Two types of grafts (tibialis anterior (TA) and the peroneus longus (PL)) were harvested from 40 donors. The grafts were divided into 4 groups according to the storage time (5 vs. 6 months) and bactericide irradiation technique (gamma-ray vs. electron-beam, both using doses of 25kGy). The grafts were soaked in a radioprotectant solution and stored at -80˚C. Cyclic loading tests (1000 cycles with 2Hz frequency between 50N and 250N loading force) and a load to failure test were performed. Young modulus of elasticity was calculated. We found that in case of TA tendons-after 21kGy gamma irradiation–a Young modulus value of 206.27MPa after 5 months of storage, and 159.67MPa after 6 months of storage were measured. When we compared datas of the e-beam irradiation, Young modulus of 141.58MPa after 5 months of storage, while after 6 months of storage, a value of 169.06MPa was measured. In case of PL tendons after gamma irradiation, a Young modulus of 163.96MPa after 5 months of storage, and 158.83MPa after 6 months of storage were measured. After the comparison of the e-beam irradiation datas, Young modulus values of 114.24MPa after 5 months of storage and 117.39MPa after 6 months of storage were measured.
The performance of TA grafts against the irradiation was superior compared to the PL tendons. The Young modulus of elasticity decreased more after irradiation via electron-beam than after gamma-ray irradiation.