Rodica Marinescu

Outside-in meniscus suture technique: 5 years' follow-up.

We present the results of a prospective study evaluating the arthroscopic technique of outside-in meniscus suture (n=68). The types of tears suitable for suture consisted of acute vertical tears, solitary or in association with a radial tear in middle third. The technique was always outside-in using resorbable sutures (2-0 PDS, 2-0 Maxon). Follow-up evaluation included clinical examination, radiographic examinations and second-look arthroscopies (n=10). There were four failures in this study, consisting of rerupture of the meniscus. Clinical results were good in 91% with complete recovery and return to physical and sportive activity, good in 3% with mild symptoms, and failure in 6% consisting of meniscus rerupture.

Pretibial Cyst Formation in ACL Reconstruction - A Case Report

Anterior cruciate ligament (ACL) reconstruction technique was under tremendous improvement during last 10 years; anatomical versus transtibial technique gradually increased, with soft tissue graft overcoming bone-tendon-bone, and biodegradable exceeding metallic implants. Still, complications related to ACL reconstruction are reported; one of it is pretibial cyst formation. Pretibial cyst formation is reported to develop between 2 and 5 years post-operation. We report a case in which the cyst was developed at 2 years after surgery; a biocomposite screw was used for fixation on tibial site, in an ACL reconstruction done with soft tissue autograft. The MRI examination suggested the diagnostic, which was confirmed by histological examination of the cyst. The screw suffered multiple fragmentation; the remnants were retrieved and analyzed. The knee stability was not affected by the cyst development. After retrieval of the screw and appropriate rehabilitation, the patient recovery was complete. The presented case confirms that even biocomposite screw may be related to these sorts of complications, mainly related to plain biodegradable screws. The case offers a point of start for analysis of the literature. A precise ethology of this kind of complications is still unknown; a lot of theories have been developed, two of them seem to be related to our case. Technical improvement together with long time surveillance of cases in which biocomposite implants were used may improve our knowledge concerning the fate of these implants.

Advanced Engineering in Orthopedic Surgery Applications

The paper reports the use of advanced engineering tools, techniques and manufacturing process for the preoperative planning, visualization and simulation of complex osteotomy of a diabetic foot (Charcot osteoarthropathy). Two case studies focused on the same clinical data are illustrating the use of medical modeling techniques, reverse engineering and Additive Manufacturing technology in the development of 3D printed anatomical model and customized surgical cutting guides, as well as the use of Augmented Reality (AR) tools for enhancing the communication and information exchange between surgeons, and between surgeons and engineers. A good and accurate communication surgeon-engineer in identifying and selecting anatomical landmarks and supporting surfaces, in establishing the resections trajectories and K-wires positions proved mandatory for the guides’ design process. The importance of using both 3D virtual models, AR models and physical models as collaboration tools is also discussed.

Metallosis - Literature Review and Particular Cases Presentation

Metallosis is an adverse event developed in relation with an orthopedic implant. It was brought into attention by metal on metal total hip arthroplasty. Lately, cases were diagnosed in total knee, total elbow, and spinal surgery. Metallic debris - released because of wear or corrosion - start an inflammatory response in a chronic condition. Beside local effects, systemic effects are also described; among them toxic effects, neurological and psychiatric, alteration in thyroid and heart function, skin rushes and discoloration. Diagnosis is helped by x-ray examination but is based on fluid aspiration with ions level determination and histological examination. Osteolysis phenomena induced by metallosis may compromise bone ingrowth and promote implant loosening; as result bone stock may be compromised. The cases we present have a particular development pattern; each of them was initiated as a result of atypical behavior of the implants. Two of them necessitated bone grafting in order to replace the reduced bone stock and all three required revision surgery. The cases emphasize the diagnosis methodology and the possible complications encountered during orthopedic implant surgery.

Alginate Used to Develop Bio-Inspired Composite Microparticles for Bone Regeneration

This work describes the synthesis of composite particles for bone regeneration. The developed method is based on a bio-inspired approach starting from the composition, properties and hierarchical organization of bone extracellular matrix (ECM). The composite material was designed as spherical particles able to ensure interconnected porosity through their assembling inside the bone defect. nanohydroxyapatite was generated in the organic matrix in order to mimic the composition and the organization of the mineral phase in bone tissue. A collagen derivative was used as main natural polymer of the organic matrix of the composite material, in order to mimic the composition of bone ECM. Alginate represents the second organic polymer due to its recognized capacity to easily generate spherical particles in divalent cations solutions. The combination of this polysaccharide with the two previously mentioned components simultaneously responds the architectural and compositional constraints of this approach. The particles were obtained using a modular electrostatic bead generator developed in our laboratory. Briefly, a solution containing the biopolymers was extruded into a mineralisation solution. Spherical particles with diameters of about 500 μm were obtained. They were characterised by scanning electron microscopy, X-ray diffraction, stability in aqueous media. The obtained results confirmed the importance of alginate to generate spherical particles and the potential of such materials to successfully serve the targeted application.

Sonication – further progress in the microbiological diagnosis in implant-associated infections

Sonication – further progress in the microbiological diagnosis in implant-associated infections Daniela Tălăpan, Raluca Mihăilescu, Olga Mihaela Dorobăț, Vlad Predescu, Rodica Marinescu, Olivera Lupescu, Florian Purghel, Marius Niculescu, Răzvan Ene, Alexandru Hera, Daniela Munteanu, Mariana Constantin, Emilia Căpraru, Angelica Tenita, Dana Jianu, Oana Săndulescu, Anca Streinu-Cercel, Monica Cârstoiu, Cătălin Cârstoiu, Victoria Aramă, Adrian Streinu-Cercel, Alexandru Rafila

Radiographic Analysis of Bone Remodeling around Hydroxyapatite Coated Femoral Stems

The study presented in the current paper was designed to investigate periprosthetic bone remodeling associated with two cementless HA coated stem models, ABG-II (Stryker) and Corail (DePuy), randomly implanted in 40 active patients at Colentina Clinical Hospital,Romania. Anteroposterior with neutral rotation and Lequesne profile radiographs of both hips were taken and several data were recorded: acetabular angle, rotation center of the hip, rotation center height with respect to the greater trochanter tip, femoral cortical thickness, cortico-medullary index at three areas (lesser trochanter (LT), 8 and 12 mm distal to LT), and osteoporosis severity according to the Singh index. The presence of osteolytic lesions in the proximal femur was assessed according to the scale proposed by Goetz in the radiographs obtained at the end of the follow-up (1 to 5 years). The radiological results showed that all stems were stable, and no evolutive radiolucent lines have been observed. We also have noticed minimal remodelling changes in 7 hips (36.61%), with minor cancellous bone densification mainly in zones 2 and 6, without cortical hypertrophy or osteoporosis. A decreased bone density in zones 1 and 7, secondary to stress-shielding, has been evident in 5 hips. Stem subsidence has been similar to that reported in literature with other hydroxyapatite coated designs.

Development of Modified Viscoelastic Solution with Magnetic Nanoparticles – Potential Method for Targeted Treatment of Chondral Injuries

Intra-articular treatments offer the advantage of achieving high active substance concentrations at the site of cartilage lesion. One problem with these drugs is that of low remanence. A method to prolong the survival time of substance inside the joint may improve the cartilage repair and patient symptoms. Targeted therapy aims to optimize the delivery of these drugs set in a solution of magnetic nanoparticles, by injection into the knee joint, in order to increase the residence time of active substances through the application of high magnetic field gradients in the joint area by using extracorporeal magnets. Synthesized magnetic nanoparticles, which were covered by layer-by-layer method in consecutive layers of protection, are stable and retain their character and magnetic-polymer composites features required to be used for their intended purpose. FTIR analysis demonstrated the presence of iron salts in the synthesized ferrofluid, and of the characteristic groups of polymer coating which demonstrated that the technique of embedding in polymer layers by layer-by-layer method is viable.

Transfemoral Fixation in Soft Tissue Cruciate Ligament Reconstructions – Composite Versus Polymeric Implant Analysis

Different methods are available for fixation on the femoral side of a quadruple soft tissue autograft in anterior cruciate ligament reconstruction and the best method is still to be found. There are also a large number of polymers in current practice, with a trend towards ceramic composites, required for better bone formation around the implant. If ceramic – polymer composites have better bioactive properties can be demonstrated only by long term in vivo follow up. Several methods of trans-femoral fixation are currently in use in our clinic – two of them being compared in this study: Rigidfix (Mitek DePuy Westwood, MA) and Biosteon (Stryker). First system produces a very stiff fixation using two implant pins made of poly-L-lactic acid (PLLA); the second technique is using a large composite (25% hydroxyapatite and 75% PLLA) suspension system with the mechanical advantage of achieving a “ press-fit” graft fixation in the tunnel. We prospectively follow our cases with clinical visits at 1, 3, 6 and 12 months – for research purposes, in a series of 20 cases (10 from each group) MRI (Siemens, 1,5 Tesla) were performed at same time intervals. Volume loss of the implant, tunnel enlargement, presence of osteolysis, fluid lines, edema and postoperative pin replacement by bone tissue were evaluated. There was no edema or signs of inflammation around the bone tunnels at more than 24 months of folllow-up. Several of the Biosteon sites were surrounded by an area of increased signal on the fat-suppressed images. At 12 months, the femoral implants showed an average volume loss of 80% (±10%) P\0.05), respectively. At 3, 6, and 12 months volume losses range from 5 % (±2%), 29% (±19%) and 89% (±7%) for the composite implant. The femoral tunnel enlargement was less than 50% of the original bone tunnel volume after 12 months. Bone ingrowth was observed in all patients. Use of a composite ceramic – polymer bioabsorbable material (enhanced to form bone) will be easily incorporated by the body, retain strength for an adequate period of time, obviate the need for secondary procedures such as hardware removal, and facilitate revision surgery.