Failure rate analysis and clinical outcomes of two different femoral tunnel positions using anteromedial portal technique in anterior cruciate ligament reconstruction.

AIM: To analyze two different femoral tunnel positions and to evaluate their correlation with clinical, functional outcomes and surgical revision rate in patients who underwent primary arthroscopic anterior cruciate ligament (ACL) reconstruction with anteromedial (AM) portal technique. METHODS: From January 2015 to October 2018, we recruited 244 patients that underwent primary single-bundle ACL reconstruction, using four strand-semitendinosus graft and AM portal technique for femoral tunnel placement. Patients were divided into two groups based on the different femoral tunnel positions: 117 patients of group A had ACL footprint center femoral tunnel position compared with 127 patients of group B, with femoral tunnel placement close to the AM bundle footprint. Preoperatively and at last follow up, all patients were assessed subjectively by Lysholm, Tegner, and International Knee Documentation Committee (IKDC) scores, while Lachman, Pivot-shift, and KT-1000 tests were performed to evaluate knee joint stability. RESULTS: Group B patients showed significantly better results in Lysholm, objective, and subjective IKDC scores compared with patients of group A (P < 0.001). A significantly higher surgical failure rate was found in group A than in group B (10.26% vs. 2.3%; P < 0.001). A higher anterior knee laxity was recorded in patients of group A than in patients of group B (1.9 ± 1.1 vs. 1.3 ± 1 mm; P < 0.001); a reduction in mean anterior tibial translation from preoperative to final follow up was found in group B compared with group A (3.5 ± 1.2 vs. 2.7 ± 1.1 mm; P < 0.001). No significant differences in the Tegner scale were found between the two groups. CONCLUSION: ACL reconstruction performed using the AM portal technique showed better and more satisfactory clinical and functional outcomes associated with a lower failure rate when the femoral tunnel had been placed more eccentrically in the footprint, in the AM bundle center position.

Design and test of a compact beam current monitor based on a passive RF cavity for a proton therapy linear accelerator.

In a medical accelerator, real-time monitoring systems of the beam and dose delivered to the patient are mandatory. In this work, we present a compact current profile detector that has been designed and tested in the framework of the TOP-IMPLART (Intensity Modulated Proton Linear Accelerator for RadioTerapy) project. This project foresees the realization of a proton linear accelerator, currently under construction at ENEA Frascati, for proton therapy applications. The linac produces a pulsed proton beam with 3 µs duration at 50 Hz repetition rate with a pulse current between 0.5 and 50 µA. A large dynamic range and spatial constraints make the use of usual noninterceptive beam diagnostics unfeasible. Therefore, the use of a beam current monitor based on a passive RF cavity working in the TM010 mode has been proposed. This paper reports the electromagnetic design of the device guided by a simplified analytical model. A prototype of such a device has been realized, characterized, and tested on the linac with a 35 MeV beam varying the beam current. The test results in air and in vacuum, together with the signal detection systems used, are presented.

THE TOP-IMPLART PROTON LINEAR ACCELERATOR: INTERIM CHARACTERISTICS OF THE 35 MEV BEAM.

In the framework of the Italian TOP-IMPLART project (Regione Lazio), ENEA-Frascati, ISS and IFO are developing and constructing the first proton linear accelerator based on an actively scanned beam for tumor radiotherapy with final energy of 150 MeV. An important feature of this accelerator is modularity: an exploitable beam can be delivered at any stage of its construction, which allows for immediate characterization and virtually continuous improvement of its performance. Currently, a sequence of 3 GHz accelerating modules combined with a commercial injector operating at 425 MHz delivers protons up to 35 MeV. Several dosimetry systems were used to obtain preliminary characteristics of the 35-MeV beam in terms of stability and homogeneity. Short-term stability and homogeneity better than 3% and 2.6%, respectively, were demonstrated; for stability an improvement with respect to the respective value obtained for the previous 27 MeV beam.

CHARACTERIZATION OF 27 MEV PROTON BEAM GENERATED BY TOP-IMPLART LINEAR ACCELERATOR.

The first proton linear accelerator for tumor therapy based on an actively scanned beam up to the energy of 150 MeV, is under development and construction by ENEA-Frascati, ISS and IFO, under the Italian TOP-IMPLART project. Protons up to the energy of 7 MeV are generated by a customized commercial injector operating at 425 MHz; currently three accelerating modules allow proton delivery with energy up to 27 MeV. Beam homogeneity and reproducibility were studied using a 2D ionizing chamber, EBT3 films, a silicon diode, MOSFETs, LiF crystals and alanine dosimetry systems. Measurements were taken in air with the detectors at ~1 m from the beam line exit window. The maximum energy impinging on the detectors surface was 24.1 MeV, an energy suitable for radiobiological studies. Results showed beam reproducibility within 5% and homogeneity within 4%, on a circular surface of 16 mm in diameter.

[Radiologic assessment of femoro-patellar instability. Personal experience and review of the literature]. / Valutazione radiologica dell'instabilità femoro-rotulea. Esperienza personale e revisione della letteratura.

PURPOSE: To propose a simple and reproducible radiological evaluation of patellofemoral instability to enable the orthopaedic surgeon to choose the best therapy. MATERIAL AND METHODS: We have evaluated retrospectively the radiographs and CT examinations of 25 patients, 15 female and 10 male, aged between 18 and 32 years. They underwent surgical treatment for patellar instability in the past 4 years. Lateral retinacular release has been performed in every patient, medial transposition of the anterior tibial tuberosity has been performed in 23 patients and in 5 of them also its distal replacement, proximal Insall's realignement was performed in 20 cases and only 1 patient underwent trochleoplasy. Preoperative conventional radiographs included antero-posterior view, true lateral view (exact superimposition of the posterior trochlear edges) and axial views at 30 degrees of knee flexion. On lateral view, the patellar height was evaluated based on Caton-Deshamps index and trochlear dysplasia assessed using the methods suggested by Dejour. A CT examination of both knees was performed: the images were taken first with knees in extension, with and without quadriceps contraction, then in flexion at 20 degrees. Patellar "bascùle" angles were measured both with quadriceps relaxed and contracted as an index of quadriceps dysplasia; the TAGT in extension was evaluated as an index of the degree of lateral position of the anterior tibial tuberosity. Preoperative conventional and CT findings were compared with those obtained postoperatively at 30.4 months from the surgical intervention. RESULTS: All patients were free from complaints after surgery. In 5 patients a high patella was corrected by distal realignement of anterior tibial tuberosity. A trochlear dysplasia with different degrees of severity was present in all cases and it was not modified by surgical treatment, with the exception of the patient who underwent trochleoplasty. In the 20 patients who underwent proximal Insall's realignment, patellar "bascùle" angles--pathological before surgery--were restored to normal values with the exception of 3 cases. In 23 patients who underwent medial transposition of anterior tibial tuberosity, the values of the TAGT were all normalized: nevertheless, in three patients low values of the TAGT were found after surgery and this condition may predispose to the development of medial patellofemoral by iperpression syndrome. CONCLUSIONS: In patients suffering from patellofemoral instability, a radiological protocol which includes conventional radiographs in two projections and a CT examination both in extension, with and without quadriceps contraction, and in flexion at 20 degrees supplies all the information needed for evaluating patellar height and mobility, trochlear dysplasia, valgism of the knee and the degree of excessive lateral position of the anterior tibial tuberosity. Careful evaluation of such abnormalities is important for selecting the best surgical treatment for each patient. It's a simple, quick, and accurate protocol that may be reproduced, even using different radiographic equipment. The collaboration between the radiologist and the orthopaedic surgeon is crucial for the correct interpretation of radiological findings, which must be evaluated together with clinical findings so that an adequate therapeutical plan could be proposed.

[Shoulder instability: diagnostic imaging]. / Instabilità di spalla: diagnostica per immagini.

Shoulder instability is often diagnosed among athletes; two clinical forms are distinguished: anatomical instability, with recurrent luxation of the shoulder, and functional instability, with pain, articular "click" and sensation of instability. Lesions of periarticular soft tissues (capsula, fibrocartilaginous labrum, gleno-humeral ligaments and rotator cuff) are common in both forms, while lesions of bone structures (humeral head and glenoid of scapula) are typical of shoulder with previous dislocation. Purpose of our retrospective study was to verify the value of magnetic resonance (MRI) and computed arthrography (arthro-CT) in diagnosing these lesions in 57 patients suffering from shoulder instability. On the basis of our results and experience we think that in a preoperative evaluation of an unstable shoulder, arthro-CT and arthro-MRI are more accurate because the intra-articular injection of a contrast medium better identifies lesions of capsula, gleno-humeral ligaments and fibrocartilaginous labrum. In other circumstances, such as the study of the shoulder for legal purposes, MRI is preferable because it offers an accurate and global evaluation of periarticular structures.

[Injuries of the cruciate ligament of the knee: diagnostic contribution of MR and spiral CT]. / Lesioni dei legamenti crociati del ginocchio: contributo diagnostico della RM e della spiral-TC.

Lesions of cruciate ligament are common after knee trauma of different degree of gravity. Lesions evaluation is possible thanks to CT and MRI. Our purpose is to verify their value in diagnosis of cruciate ligaments lesions. We retrospectively evaluated 160 patients (80 CT and 80 MRI) with subsequent diagnosis of cruciate ligaments injury. CT and MRI were performed in the acute phase and in the subacute phase within 2-3 weeks from trauma. On the basis of our results CT and MRI shown a reduced sensitivity in acute phase owing to the intraarticular haemorrhage; in this phase MRI gives more information about fibres interruption. In subacute or chronic phase, both methods are correct in recognising the lesions but MRI is more sensitive and accurate. It is a real wish that, with more MRI machines diffusion, this method will be preferred in the study of cruciate ligaments both in acute phase and subacute-chronic phase.

[Osteoid osteoma of the limbs: the clinical aspects and diagnostic problems]. / Osteoma osteoide degli arti: aspetti clinici e problemi diagnostici.

The authors report their experience in the treatment of "osteoid osteoma", drawing attention to the great clinical polymorphism of this affection. They also demonstrate the reliability of a preliminary systematic study with bone scan and CT, which are indispensable to early diagnosis and correct surgical procedure.