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Alexandros N Mavrodontidis

Publications and source records attributed to Alexandros N Mavrodontidis.

5 recordsLinked to original sources
PubMed2004

Bilateral absence of the patella in nail-patella syndrome: delayed presentation with anterior knee instability.

A 27-year-old man, while serving in the armed forces, presented with complaints of right knee pain of 3 months duration. The patient reported pain localized on the lateral side of the right knee, especially during long-distance walking and stair climbing, and a feeling of giving way. There was no history of recent or remote trauma to the knee joint. At that time, he presented with knee pain and instability consistent with anterior cruciate ligament (ACL) insufficiency. During physical examination, the diagnosis of nail-patella syndrome (NPS) was made, but magnetic resonance imaging (MRI) of both knees revealed intact ACLs. The reported case presents NPS as a potential nontraumatic cause of anterior knee instability. In our patient, a discrepancy between the clinical and imaging findings was present. The initial clinical examination was consistent with ACL rupture or aplasia and this led to MRI evaluation of the knee, which showed an intact ACL, contrary to the initial diagnosis. It should be noted that anterior instability has been described after patellectomy and could be attributed to complete absence of the patella, which is rare in NPS.

Adult↗
PubMed2004

Non-union of femoral neck fractures with osteonecrosis of the femoral head: treatment with combined free vascularized fibular grafting and subtrochanteric valgus osteotomy.

Femoral neck fractures, frequently complicated by non-union and femoral head osteonecrosis,present a difficult clinical situation, especially when young patients are concerned. Existing treatment options are valgus osteotomy to address the biomechanical factors or bone grafting to address the biologic factor. The authors describe the operative technique and results of combined subtrochanteric valgus osteotomy and free vascularized fibular grafting in management of five young patients with both non-union and avascular necrosis.

Adolescent↗
PubMed2004

Low-intensity transosseous ultrasound accelerates osteotomy healing in a sheep fracture model.

BACKGROUND: Low-intensity transcutaneous ultrasound can accelerate and augment the fracture-healing process. The aim of this study was to investigate the effect of transosseous application of low-intensity ultrasound on fracture-healing in an animal model. METHODS: A midshaft osteotomy of the left tibia was performed in forty sheep. An external fixator was used to stabilize the osteotomy site. A thin stainless-steel pin was inserted into the bone, 1.0 cm proximal to the osteotomy site. Ultrasound was transmitted through the free end of this pin, with a PZT-4D transducer. In twenty animals, the treated limb received a 200-microsec burst of 1-MHz sine waves repeated at 1 kHz with an average intensity of 30 mW/cm(2) for twenty minutes daily. Twenty other animals underwent the same surgery but did not receive the ultrasound (controls). Animals were killed at seventy-five and 120 days postoperatively. Radiographic evaluation was performed every fifteen days. Mechanical testing and quantitative computed tomography were performed after death. RESULTS: Fractures treated with ultrasound healed significantly more rapidly, as assessed radiographically, than did the controls (seventy-nine compared with 103 days, p = 0.027). On day 75, the mean cortical bone mineral density (and standard deviation) was 781 +/- 52 mg/mL in the treated limbs compared with 543 +/- 44 mg/mL in the control group (p = 0.014), and the average ultimate strength (as assessed with a lateral bending test) was 1928 +/- 167 N in the treated limbs compared with 1493 +/- 112 N in the control group (p = 0.012). No significant differences were noted on day 120. CONCLUSIONS: This study demonstrated that low-intensity transosseous ultrasound can significantly accelerate the fracture-healing process, increase the cortical bone mineral density, and improve lateral bending strength of the healing fracture in a sheep osteotomy model.

Animals↗
PubMedDate not supplied

Posterior tibial subluxation and short-term arthritis resulting from failed posterior cruciate ligament reconstruction.

Posterior tibial subluxations because of combined or isolated posterior cruciate ligament (PCL) injuries require detailed evaluation. PCL reconstructions are difficult procedures because of the low rate of such injuries and the complex anatomy of the ligament. We report on 2 cases of failed PCL reconstruction because of malpositioned femoral tunnels. These 2 cases support the existing biomechanical evidence that the correct placement of the tunnels, especially in the femur, is a major factor in defining the outcome. It seems that the drilling of the tunnels, especially in the femur, during PCL reconstruction must be performed with accuracy and always be evaluated in cases of graft failure. In addition, failed PCL reconstructions are usually accompanied by a short-term excessive arthritis that results in poor functional outcome.

Achilles Tendon↗