The major proximal femoral defects: megaprosthesis in non oncological patients - A case series.

We identified 39 patients (23 female and 16 male) underwent hip revisions through mega-prosthesis. The most common causes were periprosthetic fractures, periprosthetic osteolysis and consequences of infected arthroplasty. The average follow-up was 5 years (2.1 to 6.5), and average age was 69 years (47 to 78). At the final follow-up all the implants resulted functional and osteointegrated. The Merle D'Aubignè and Postel hip rating scale was used for the evaluation, better results were observed in periprosthetic fractures. Postoperative complications occurred in eight patients. Thus, megaprosthesis were a reasonable surgical option in the management of major femoral defects.

Three generations of treatments for osteoporotic vertebral fractures: what is the evidence?

The management of vertebral compression fractures (VCFs) is based on conservative treatment and minimally invasive vertebral augmentation procedures. However, the role of vertebral augmentation is now being questioned by clinical trials and extensive studies. The aim of this review is to report the most relevant evidences on effectiveness, safety, and indications of the currently available vertebral augmentation techniques. Conservative treatment with bracing is effective in reducing acute but it has no effect on segmental kyphosis progression and pseudoarthrosis can occur. Percutaneous vertebroplasty (PV) was the first vertebral augmentation technique to be proposed for the treatment of VCFs. Two blinded and randomized clinical trials compared PV to a sham procedure and no significant differences in terms of efficacy were reported. More recent studies have suggested that PV can still benefit patients with acute VCFs and severe pain at onset. Balloon kyphoplasty (BK) was developed to improve the segmental alignment restoring the height of collapsed vertebrae. BK allows similar pain relief and disability improvement, as well as greater kyphosis correction compared to PV, moreover BKP seems to reduce cement leakage. Vertebral body stenting (VBS) and the KIVA system are third generation techniques of vertebral augmentation. VBS aims to increase the effectiveness in restoring the segmental alignment, while the KIVA system can prevent cement leakage. These techniques are effective and safe, even if their superiority to BK has yet to be proven by studies with a high level of evidence.

Extracapsular femoral neck fractures treated with total hip arthroplasty: identification of a population with better outcomes.

Background: Femoral neck fractures (FNF) are associated to patient's disability, reduced quality of life and mortality. None of the fixation devices commonly used for extracapsular (EC) FNF (i.e., dynamic hip screws (DHS) and intramedullary nails (IN)) is clearly superior to the other, especially in case of unstable fractures (31.A2 and 31.A3 according to AO/OTA classification). The aim of our study was to identify a sub-population of patients with EC fractures in which better outcomes could be obtainable using total hip arthroplasty (THA). Methods: All patients with EC unstable fractures treated with THA were included in the present study. Demographic data, American Society of Anesthesiologists (ASA) score, hospitalization length, transfusion rate, implant-related complications and mortality rate were collected. Clinical outcomes were evaluated using the Oxford Hip Score (OHS), while patients' general health status through the 12 Item Short Form questionnaires (SF-12). Results: 30 patients (7 male; 23 female) with a mean age of 78.8 years were included. The 1-year mortality rate was 13.3%. The mean OHS was 27.5, while the mean SF-12 were 45.84 for the mental item and 41.6 for the physical one. Age was the only factor associated with the OHS and patients older than 75 years presented a 12- fold higher risk of developing bad outcomes. Conclusions: THA seems to be a viable option for unstable EC fractures, with good clinical outcomes, especially in patients younger than 75 years of age. The mortality rate associated with THA in EC fractures is low and anyway comparable with IN.

Problems, complications, and reinterventions in 4893 onlay humeral lateralized reverse shoulder arthroplasties, a systematic review: part II-problems and reinterventions.

BACKGROUND: Several modifications to the original Grammont reverse shoulder arthroplasty (RSA) design have been proposed to prevent distinctive issues, such as both glenoid and humeral lateralization. The aim of this systematic review was to determine rates of problems, complications, reoperations, and revisions after onlay lateralized humeral stem RSA, hypothesizing that these are design related. METHODS: This systematic review was performed in accordance with the PRISMA statement guidelines. A literature search was conducted (1 January 2000 to 14 April 2020) using PubMed, Cochrane Reviews, Scopus, and Google Scholar, employing several combinations of keywords: "reverse shoulder arthroplasty," "reverse shoulder prosthesis," "inverse shoulder arthroplasty," "inverse shoulder prosthesis," "problems," "complications," "results," "outcomes," "reoperation," and "revision." RESULTS: Thirty-one studies with 4893 RSA met inclusion criteria. The 892 postoperative problems and 296 postoperative complications represented overall problem and complication rates of 22.7% and 7.5%, respectively. Forty-one reoperations and 63 revisions resulted, with overall reoperation and revision rates of 1.7% and 2.6%, respectively. CONCLUSIONS: Problem, complication, and reintervention rates proved acceptable when implanting a high humeral lateralization stem RSA. The most frequent problem was scapular notching (12.6%), and the most common postoperative complication was scapular stress fracture (1.8%). An overall humeral complication rate of 1.9% was identified, whereas no humeral fractures or stem loosening were reported with short stems. Infections (1.3%) were the most common reason for component revision, followed by instability (0.8%). LEVEL OF EVIDENCE: Systematic review IV.

The Rising Moon sign is specific and sensitive in the diagnosis of bucket handle tears of the medial meniscus.

PURPOSE: Bucket handle tears of the meniscus are common and can lead to locking, extension deficit and functional impairment. The diagnosis is determined by a combination of physical examination and imaging, but in some cases the diagnosis may be challenging since specific clinical tests are lacking. The aim of the present study was to assess the value of a new clinical test, the elective pain at the anterior aspect of the joint line (defined as the "Rising Moon sign") in the diagnosis of bucket handle tears of the medial meniscus. METHODS: Forty patients treated for a bucket handle of the medial meniscus were enrolled as the study group and were compared to a matched group of 40 patients with a posterior horn tear of the medial meniscus and 50 healthy subjects. The following aspects were investigated in the groups: body mass index, extension deficit, pain at the posterior aspect of the joint line (PPJL), at the middle joint line (PMJL), at the anterior join line (PAJL) and at combined hyperflexion of the knee and external rotation of the foot (PHE). Pain at the anterior joint line (PAJL) was defined as the Rising Moon sign. RESULTS: In the bucket handle group the average flexion contracture was 12° (0-30°). The average PPJL was one (0-2), the average PMJL was 1.6 (0-3), PAJL was 2.5 (1-3) and PHE was 1.6 (1-2). In the posterior horn tear group the average flexion contracture was 0.9° (- 10 to 5°). The average PPJL was 2.2 (1-3), the average PMJL was 1.4 (0-3), PAJL was 0.6 (0-2) and PHE was 2.5 (1-3). The rising moon showed 95% sensitivity and 98% specificity in the diagnosis of bucket handle tears. In addition it showed a positive predictive value of 97.4% and negative predictive value of 96%. Finally it also demonstrated high inter-observer reliability (0.905). CONCLUSIONS: The "Rising Moon" sign has shown to be highly predictive for bucket handle tears of the medial meniscus with very high specificity and sensitivity. In addition it is easy to perform with very high inter-observer reliability. LEVEL OF EVIDENCE: Level IV.

Atypical periprosthetic femoral fractures of the hip: characterisation of three cases.

INTRODUCTION: Long-term use of bisphosphonates (BPs) has been associated with a specific type of tensile side femoral stress fracture known as Atypical Femoral Fracture (AFF). Theoretically periprosthetic femoral fractures (PFF) should be excluded from the diagnosis of AFF. However, emerging evidence correlates prolonged BPs use with the occurrence of a type of PFF with an atypical pattern (atypical PFF, APFF). The aim of the present study is to report 3 cases of APFF treated at a single centre. METHODS: Clinical and radiographic records of PFF that occurred between January 2016 and August 2018 were retrospectively reviewed. All patients meeting the American Society for Bone and Mineral Research (ASBMR) criteria for definition of PFF were included. Management strategies for APFF and patient outcomes, including fracture healing and hip function (assessed by the Oxford Hip Score [OHS]) were collected. RESULTS: 3 patients in the study period were identified as APFF (1 incomplete, 2 complete). All patients were females with a mean age of 83.3 years. All patients were treated with lateral plating. The application of a contralateral strut allograft resulted in fracture healing in cases of complete fractures. Mean OHS at final follow-up was 34.3. CONCLUSIONS: Despite occurring around a hip stem like PFF, APFF had peculiar clinical and radiographic features, making them more similar to AFF. Therefore, the orthopaedic surgeon should also consider the natural history and healing problems associated with AFF prior in order to choose the most appropriate management for APFF.

Neglected femoral neck fractures in cerebral palsy: a narrative review.

Hip fractures are severe conditions with a high morbidity and mortality, especially when the diagnosis is delayed, and if formulated over 30 days after the injury, is termed a 'neglected femoral neck fracture' (NFNF).Cerebral palsy (CP) is probably one of the major risk factors for NFNF in Western countries, mainly because of both cognitive and motor impairments. However, considering the high prevalence of fractures in these patients, the incidence of NFNF in this population is probably underestimated, and this condition might result in persistent hip or abdominal pain.Several techniques are available for the treatment of NFNF (i.e. muscle pedicle bone graft, fixation with fibular graft, valgisation osteotomy), but most of them could affect motor function.Motor function must be preserved for as long as possible, in order to enhance the quality of life of CP patients.After discussing published NFNF cases in CP patients and available treatment options, a practical approach is proposed to facilitate the orthopaedic surgeon to both early identify and appropriately manage these challenging fractures. Cite this article: EFORT Open Rev 2020;5:58-64. DOI: 10.1302/2058-5241.5.190019.

Tibial internal rotation negatively affects clinical outcomes in total knee arthroplasty: a systematic review.

PURPOSE: The aim of this systematic review is to analyze the effect of tibial rotational alignment after total knee arthroplasty (TKA) on clinical outcomes and assess the eventual cut-off values for tibial TKA rotation leading to poor outcomes. METHODS: A detailed and systematic search from 1997 to 2017 of the Pubmed, Medline, Cochrane Reviews, and the Google Scholar databases was performed using the keyword terms "total knee arthroplasty", "total knee replacement", "tibial alignment", "tibial malalignement", "tibial rotation", "rotational error", "axis", "angle", "tibial malrotation", "clinical outcome", in several combinations. The modified Coleman scoring methodology (mCMS) was used. All the primary TKAs studies analyzing correlation between clinical results and tibial rotation were included. RESULTS: Five articles met the inclusion criteria. A total of 333 arthroplasties were included in this review; 139 had tibial component malalignment, while 194 were in control groups. The mean age of patients was 67.3 (SD 0.57) years. The mean average postoperative follow-up delay was 34.7 months (range 21-70). The mean mCMS score was 59.2 points indicating good methodological quality in the included studies. Functional outcomes were assessed through KSS, OKS, KOOS and VAS, negatively related to tibial internal rotation. CONCLUSIONS: Our review confirmed that excessive internal rotation of the tibial TKA component represents a significant risk factor for pain and inferior functional outcomes after TKA (> 10° of internal rotation demonstrated the common value), since external rotation does not affect the results. However, a universal precise cut-off value has not been found in the available literature and there remains a debate about CT rotation assessment and surgical intra-operative landmarks. LEVEL OF EVIDENCE: III.

Unicompartmental Knee Arthroplasty: Modes of Failure and Conversion to Total Knee Arthroplasty.

Despite the excellent success rates of the modern unicompartmental knee arthroplasty (UKA), results of knee replacement registries still shows a relatively high revision and failure rate for UKA, especially when compared with traditional total knee arthroplasty (TKA). Bearing dislocation continues to be advocated as the predominant mechanism of failure in mobile UKA, whereas polyethylene wear and aseptic loosening remains the main cause of failure of fixed UKA. Degeneration of the unreplaced compartments has been reported in both mobile and fixed designs. When the revision is required, most of failed UKAs are converted to TKAs. Surgical challenges of the UKA revision, and outcomes of UKA converted to TKA are still debated in literature.

I.S.Mu.L.T. first-time patellar dislocation guidelines.

Primary traumatic patellar dislocation is common, particularly in young active individuals. A consensus on its management is still lacking. The present work provides easily accessible guidelines to be considered as recommendations for a good clinical practice developed through a process of systematic review of the literature and expert opinion, to improve the quality of care and rationalize the use of resources. LEVEL OF EVIDENCE: Ia.

Anterior cruciate ligament reconstruction in adolescents (Tanner stages 2 and 3).

PURPOSE: Management of anterior cruciate ligament injuries in skeletally immature patients (in Tanner stages 2 and 3) is controversial. Conventional reconstruction used in adults can cause iatrogenic growth disturbance due to physeal damage, and studies that report long-term results using a specific technique are scarce. The aim of this study is to evaluate in a large series the mid- and long-term results of a partial transphyseal technique and define the safe percentage of lesions of the femoral growth plate. METHODS: Between 1989 and 2012, 42 adolescents at risk of growth disturbances (growth prediction of lower limbs >5 cm-Tanner 2, 3) underwent reconstruction of the anterior cruciate ligament using the semitendinosus and gracilis tendons. Growth characteristics of all the patients were assessed preoperatively, and the percentage of damage that would be produced in the femoral physis by the drilling of a 6-mm-diameter tunnel was determined. The technique used achieved graft fixation at both insertion sites, drilling the femoral physis and avoiding the tibial physis. We distinguished two groups: (a) long-term follow-up (mean 13 years 7 months, min 10.9, max 16.2) and (b) medium follow-up (mean 6 years 3 months, min 3.7, max 9.9). All knees were evaluated subjectively by history and objectively by KT2000 testing, and X-rays of both knees were compared for osteoarthritis using the Kellgren-Lawrence classification. RESULTS: In group A (12 patients) one osteoarthritis grade 2, one instability, and ten good stability and function were observed. The mean KT2000 arthrometer values at 30 lb showed a difference of +2.4 mm (range 1-4 mm) between the operated and non-operated sides (p < 0.05). In group B (21 patients) no growth disturbance of the lower limbs, two failures (reinjury while participating in pivoting sports), and 19 good stability and function were observed. The mean KT2000 arthrometer values at 30 lb showed a difference of +1.9 mm (range 1-5 mm) between the operated and non-operated sides (p < 0.05). The average IKDC score of all the patients was 90 (min: 68, max: 97). None of the adolescents had consequences on growth after an eccentric damage passing tendons less than 7% on the frontal plane and of 1% on cross-sectional area of the femoral physis, and after an oblique tunnel passing 6-mm-diameter tendons of the tibial epiphyseal nucleus. CONCLUSIONS: This study defines the possibility to perform a partial transphyseal intra-articular ACL reconstruction in patients in Tanner stages 2 and 3 that avoids tibial physis, involves the distal femoral physis, and produces good results at mid- and long-term follow-up without causing growth disturbances. LEVEL OF EVIDENCE: IV.

Reliability of forced internal rotation and active internal rotation to assess lateral instability of the biceps pulley.

PURPOSE: the aim of this study was to investigate the relationship between positive painful forced internal rotation (FIR) and lateral pulley instability in the presence of a pre-diagnosed posterosuperior cuff tear. The same investigation was conducted for painful active internal rotation (AIR). METHODS: a multicenter prospective study was conducted in a series of patients scheduled to undergo arthroscopic posterosuperior cuff repair. Pain was assessed using a visual analog scale (VAS) and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) was administered. The VAS score at rest, DASH score, and presence/absence of pain on FIR and AIR were recorded and their relationships with lesions of the lateral pulley, cuff tear patterns and shape of lesions were analyzed. RESULTS: the study population consisted of 115 patients (mean age: 55.1 years) recruited from 12 centers. The dominant arm was affected in 72 cases (62.6%). The average anteroposterior extension of the lesion was 1.61 cm. The mean preoperative VAS and DASH scores were 6.1 and 41.8, respectively. FIR and AIR were positive in 94 (81.7%) and 85 (73.9%) cases, respectively. The lateral pulley was compromised in 50 cases (43.4%). Cuff tears were partial articular in 35 patients (30.4%), complete in 61 (53%), and partial bursal in 19 (16.5%). No statistical correlation between positive FIR or AIR and lateral pulley lesions was detected. Positive FIR and AIR were statistically associated with complete lesions. Negative FIR was associated with the presence of partial articular tears. CONCLUSIONS: painful FIR in the presence of a postero-superior cuff tear does not indicate lateral pulley instability. When a cuff tear is suspected, positive FIR and AIR are suggestive of full-thickness tear patterns while a negative FIR suggests a partial articular lesion. LEVEL OF EVIDENCE: level I, validating cohort study with good reference standards.

Sonication technique improves microbiological diagnosis in patients treated with antibiotics before surgery for prosthetic joint infections.

Microbiological diagnosis is crucial for the appropriate management of implant-associated orthopedic infections (IAOIs). Sonication of biomaterials for microbiological diagnosis has not yet been introduced in routine clinical practice. Aim of this study was to describe the advantages and feasibility of this procedure in the clinical setting. We prospectively studied 56 consecutive patients undergoing revision because of IAOI and compared the sensitivity of sonication of explanted orthopedic implants with standard cultures. Patients were divided into two groups: those with foreign body infection (FBI, 15 patients) and those with prosthetic joint infection (PJI, 41 patients). Clinical, radiological and microbiological features were recorded. In the PJI group the sensitivity of sonication in detecting bacterial growth was higher than conventional culture (77% vs 34.1% respectively, p<0.002), while no difference was observed in the FBI group (85.7% vs 86% respectively, p>0.05). Coagulase-negative Staphylococci accounted for 90% of the bacteria detected by sonication. Moreover, we found that in the PJI group the sensitivity of sonication was not affected by the timing of antibiotic interruption before surgery. Sonication remains an important tool to improve microbiological diagnosis in PJIs, especially in patients who received previous antimicrobial treatment.

Medial capsule reefing in patellar instability.

PURPOSE: The efficacy of medial capsule reefing in the treatment of patellar instability is well documented. Aim of the present study was to prospectively evaluate the outcomes of an all-arthroscopic medial capsule reefing technique in young patients with painful patella syndrome and potential patellar instability. METHODS: Thirty patients with painful patellar syndrome and potential patellar instability having undergone a minimum of 6 months of intensive rehabilitation were enrolled in the present study. All subjects were evaluated with physical examination, clinical and functional outcomes and complete imaging study. RESULTS: All patients were reviewed at an intermediate follow-up of 72 months. Average Kujala score improved from 72.9±15.0 to 88.4±7.6 (p<0.0001), average Larsen score from 15.0±2.5 to 17.2±2.2 (p<0.002), average Lysholm from 63.8±16.7 to 87.9±11.7 (p<0.0001) and average Fulkerson score from 69.5±21.5 to 90.8±9.8 (p<0.0001). No intraoperative or postoperative complications were recorded. Ninety per cent of patients were very satisfied or satisfied with their functional result. Twenty-eight patients were reviewed at the final follow-up, 120 months after surgery. Average Kujala was 87.7±8.8 (p<0.0001), average Larsen was 16.8±2.7 (p<0.01), average Lysholm was 87.6±14.3 (p<0.0001), and average Fulkerson was 87.2±13.9 (p<0.0001). Almost 86% of patients were very satisfied or satisfied with their result. However, slight deterioration of the outcomes over time was observed. CONCLUSION: At the final follow-up, the outcomes of all-arthroscopic technique were significantly improved from preoperative values; however, they were slightly inferior at the 72 months follow-up. This slight deterioration of the outcomes may be the consequence of the reduction in physical activities. LEVEL OF EVIDENCE: Case series, Level IV.

Knee flexion after total knee arthroplasty reduces blood loss.

PURPOSE: Extensive blood loss after total knee arthroplasty (TKA) may be a potential problem since it leads to anaemia, increased need for transfusion and prolonged hospitalization. Aim of this study was to investigate the effects of postoperative knee flexion after TKA on blood loss and the need for transfusion. METHODS: One hundred consecutive patients undergoing primary TKA from 2012 to 2013 were randomizely divided into two groups. In one group, the knee was extended for the first 6 h after surgery, whereas in the other was flexed at 90° for the same time. Two doses of endovenous tranexamic acid were administered in all subjects. Patients were homogeneous for all the possible confounding factors. RESULTS: Calculated blood loss was 846 ± 197 (ml) in the flexion group and 1,242 ± 228 (ml) in the extension group (p < 0.05). Drop of haemoglobin levels at 24 h in the study group and the control group was 1.9 ± 0.8 (g/dl) and 3.0 ± 0.5 (g/dl), respectively (p < 0.01). Drop of haematocrit at 24 h was 4.5 ± 0.2 (%) in the flexion group and 6.7 ± 0.3 (%) in the extension group (p < 0.05). Blood transfusion was necessary in 5 patients in the control group and was not necessary in any patient of the study group. Average knee flexion at day 7 was 105° ± 4° in the flexion group and 98° ± 7° in the extension group. CONCLUSION: Knee flexion at 90° after TKA, associated with the intraoperative use of tranexamic, acid is an effective method to reduce blood loss and the need for blood transfusion. The routine use of the present protocol is effective in reducing social costs and length of hospitalization of TKA procedures.

Total knee arthroplasty after high tibial osteotomy.

High tibial osteotomy may be indicated in the treatment of varus knee in young, active patients. The preservation of proprioception and native joint and biomechanics is crucial for functional recovery in these patients. However, deterioration of initial good results can occur with time. In such cases, revision with total knee arthroplasty is indicated. However, this is a more surgically demanding option compared with a primary prosthesis. Accurate preoperative planning is mandatory to decrease the risk of intraoperative complications. A precise surgical technique, which is crucial to improving functional outcomes, includes hardware removal, joint exposition, tibial deformities due to previous osteotomy, and managing soft tissue mismatches. Possible technical challenges and surgical solutions exist for each of these aspects. However, several studies report lower functional results compared with primary implants. Thus, patients should be informed before high tibial osteotomy about its failure rate, the difficult surgical aspects of an additional prosthesis, and less satisfactory clinical results.

Misdiagnosis of soft tissue sarcomas of the lower limb associated with deep venous thrombosis: report of two cases and review of the literature.

BACKGROUND: Deep venous thrombosis (DVT) or pulmonary embolism (PE) is a rare, but not exceptional presentation of soft tissue sarcomas (STSs). Due to the remarkable difference in the incidence between DVT or PE and STSs, this type of STS presentation is usually associated with a considerable delay in tumor diagnosis and treatment. CASE PRESENTATION: We describe two cases of STS who presented with DVT and PE. Physical and radiographic examination only showed the presence of DVT. Both patients were treated for DVT or PE for several months. Due to the persistence of symptoms and the inefficacy of anticoagulant therapy, magnetic resonance imaging (MRI) was performed, which revealed the presence of a lower limb mass in both cases. The definite diagnosis was reached via excisional biopsy and histological examination.In one case, MRI showed a large tumor in the anterior muscle compartment of the right thigh, with thrombosis of the right common femoral vein and involvement of the ipsilateral common iliac vein and inferior vena cava until the confluence of the renal veins. In the other case, MRI showed a large tumor in the middle third of the right thigh. The lesion was in close proximity to the superficial femoral vein that appeared compressed and showed signs of thrombosis. In both cases, histological examination revealed a high-grade leiomyosarcoma. CONCLUSION: STSs of the lower extremities can rarely present with DVT or PE. This possibility should be considered in the differential diagnosis of painful leg swelling, especially in patients with recurrent or refractory venous thrombosis. When a STS is suspected, MRI should be obtained followed by excisional biopsy of the eventual mass. A delay in diagnosis and treatment of STSs often results in very poor prognosis.Level of evidence. IV.

Patellofemoral instability: surgical treatment of soft tissues.

Instability of the patella is a relatively frequent occurrence in adolescents. Its pathogenesis, which is multi-factorial, is still much debated. Stability of the patella is guaranteed by a delicate balance of a series of factors (osteo-cartilaginous, ligamentous and muscular), and it is not surprising that alteration of one or more of these can lead to pathological conditions that can range from simple anterior pain associated with a hypermobile patella to recurrent dislocation. The aim of surgical treatment is to correct these anatomical abnormalities. Surgical procedures on the soft tissues comprise reefing, realignment and reconstruction of the medial stabilizing structures, and release of the lateral structures. These procedures, although having precise indications, provide the surgeon with the instruments necessary to deal with almost all these anatomo-pathological conditions. Furthermore, preserving the osteo-cartilaginous components results in less morbidity than is associated with traditional surgical procedures, such as trochleoplasty and transposition of the anterior tibial tuberosity.

Modular augmentation in revision total knee arthroplasty.

PURPOSE: Controversy exists about the real effectiveness of modular augmentation to manage bone defects in revision total knee arthroplasty. The purpose of this study was to determine whether use of modular augmentation to reconstruct severe defects (1) significantly increased overall outcomes, (2) caused radiolucency or osteolysis and (3) affected mid-term survivorship of knee revisions. The hypothesis was that modular augmentation provides a good survivorship of knee revisions. METHODS: Thirty-eight consecutive revision knee arthroplasties were followed for a median follow-up period of 7 (4.5-9) years. Type 2 and 3 defects were treated with metal augments, tantalum cones and modular cementless stems. Patients were assessed using the IKS knee and function scores and the HSS score. RESULTS: The median IKS knee and function scores and HSS score were 34 (15-58), 19.5 (13-39) and 30 (24-60) points before the operation, respectively, and 78 (49-97), 76 (58-90) and 80.5 (64-98) points (p < 0.001) at the latest follow-up. The median knee flexion increased from 82° (31°-110°) to 116° (100°-129°) (p < 0.01). Tibial radiolucencies were observed in 2 (5.2 %) cases. Re-revision was necessary in three (7.9 %) patients. CONCLUSIONS: Modular augmentation may reduce the need for allografting to treat severe bone defects, providing a well-functioning and durable knee joint reconstruction.

Acute patellar dislocation. What to do?

Acute patellar dislocation is a common knee injury that occurs most often in adolescents, frequently associated with sporting and physical activities. Patellar re-dislocation after the first episode appears to depend primarily on the medial patellofemoral ligament injury which represents the primary ligamentous restraint, providing about 50-60 % of the restraining force against lateral patellar displacement. Clinically, up to 94-100 % of patients suffer from medial patellofemoral ligament rupture after first-time patellar dislocation. Controversy regarding how patients with first patellar dislocation should be managed still exists. Though most authors have reported good results with the conservative treatment after a first-time dislocation, several circumstances may warrant surgical intervention. A surgical approach would be necessary in the presence of severe cartilage damage or a relevant disruption of the medial stabilizers with subluxation of the patella. In these cases, the repair/reconstruction of medial stabilizers should follow the treatment of the chondral injury. Medial patellofemoral ligament reconstruction may be a more reliable method of stabilizing the patella than its repair, which has limitations related to the medial patellofemoral ligament injury location. Nowadays, there is no evidence available where osseous abnormalities should be addressed in addition to restoring the medial patellofemoral ligament.