Purpose of study: To investigate and compare the characteristics of the reconstructed articular surface microscopically and histologically after a time period of 6 weeks following the treatment of a focal defect of the right femoral head with subchondral drilling and autologous osteochondral transplantation in rabbits

Material and method: A 2,5 mm diameter and 3 mm depth iatrogenic osteochondral defect in the anterolateral weight bearing area of the right femoral head was created in 12 rabbits. In a group of 6 rabbits the lesion was treated with autologous osteochondral transplantation. The donor site for the transplant was the lateral condyle of the ipsilateral knee joint. The other group of 6 rabbits was treated with subchondral drilling. Both groups were sacrificed after a time period of 6 weeks and specimens were evaluated histologically under the classification system of the ICRS. For statistical analysis we used the Mann – Wittney test

Results: According to the ICRS score statistical significance was found for all variables between the 2 groups (subchondral drilling 6 weeks vs autologous osteochondral transplantation 6 weeks).: articular surface (p=0,049), matrix (p=0,003), cell distribution (p< 0,0005), subchondral bone (p=0,010), cartilage mineralization (p=0,0) except cell population viability.

Discussion: In comparison to subchondral drilling, autologous osteochondral transplantation provided better results concerning the smoothness and continuity of the articular surface, the consistency of the matrix with dominance of the hyaline and mixed hyaline – fibrocartilage type of tissue, the normality of subchondral bone and the columna r distribution of cells. The viability of the cell populations was the same for both methods. The incorporation of the osseous part of the graft was successful in all cases and the surgical procedure did not produce any necrosis of the femoral head.

Conclusion: In cases of focal osteochondral defect of the femoral head in rabbits, reconstruction of the articular surface through autologous osteochondral graft transplantation gives superior macroscopical and histological results in comparison to subchondral drilling

Aim: To evaluate the feasibility of Norian S.R.S in the treatment of comminuted distal radius fractures.

Material and methods: 24 patients with comminuted distal radius fractures were open reduced and preserved with external fixation. The bone gaps were filled with Norian S.R.S. The wrist was mobilized at the 3rd postoperative week and the external fixation was removed the 4th–6th postoperative week, when the fracture healing was radiologically confirmed. All the patients had regular clinical and radiological control the first postoperative date and the 1rd, 3rd, 4th postoperative week and monthly until the 9th postoperative month.

Results: In the postoperative follow-up we didn’t note any loss of reduction and the joint range of motion compared with the contralateral exceeded 50% in 3 months and came close to 85% in 6 months. There were no clinically significant adverse effects or complications.

Conclusions: We believe that the use of Norian S.R.S. offers the potential for filling bony voids, does not exhibit tissue reactions and is progressively absorbed. The results of this study are comparable with other therapeutic approaches. Additionally, the use of the Norian S.R.S offers the potential of earlier mobilization and as an implant is bioabsobable through osteoclastic activity. In conclusion we believe that use of Norian S.R.S in the filling of bony defects in the comminuted distal radius fractures is a reliable and safe method of treatment.

Aim: To compare two implants, the Gamma Nail and the ACE Trochanteric Nail in the treatment of pertrochanteric femoral fractures.

Patients and methods: Sixty patients were randomized on admission to two treatment groups. Thirty patients were treated with the Gamma nail implants , and thirty had intramedullary fixation with ACE Trochanteric NailI . The average age of these patients was 79 years. 22 patients were men and 38 women. 11 fractures were stable and 49 unstable. Patients were followed for 1 year and had a regular clinical and radiological review at 1, 3 and 6 months postoperatively. Operation time, intra-operative blood loss and blood transfusion and complications were recorded. The mobility score was used to assess the preinjury and postoperative mobility status. All the patients were operated within 24 hours after their accident and 39 of them within the first 6 hours.

Results: There were no complications during the surgery. All the patients were mobilized the first 24 hours post operatively irrespectively of the fracture’s type, and weight bearing was permitted as tolerated. The mean follow up time was 8 months (range 6 to 12 months). 3 patients were lost at the follow up and 2 died. Union of the fracture was achieved in all 55 patients. There was no statistically significant difference between the two groups with regard to intraoperative blood loss and the duration of the surgery. There was no mechanical failure of the implants despite the early patients mobilization. All the patients achieved mobility status similar to the preoperative at the latest follow up.

Conclusions: Based on our study, intramedullary nailing of pertrochanteric hip fractures represents a reliable method of treatment. We did not observe any differences in the two patient groups concerning the operation time, the intraoperative blood loss, the postoperative complications and the patients functional status at the latest follow up.

Aims: The topographical measurement and representation of the ACL insertion on the tibial plateau, based on a greek population sample. Methods: Fourty eight tibial plateaus were explanted during TKA surgery in 33 female and 15 male patients (average age of 71.2 yrs) suffering from osteoarthritis and rheumatoid arthritis. By means of a calliper, measurements were conducted in order to determine the dimensions shown. Data were used for a topographical representation.

Conclusions: To the authors’ best knowledge, this is the first such anthropometric study on a greek population and its results provide a confirmation on the relatively wide base of ACL insertion on the tibial plateau. The biomechanical performance of this natural configuration for a full range of motion, is possibly not sufficiently reproduced by conventional ACL reconstruction techniques using just one bundle.

Aims: The evaluation of the results becoming from the use of demineralized bone matrix (DBM) in the bone defects. Methods: In the present study the above substance was implanted during the period 2000-2002 (28 months) to 24 patients, 11 males and 13 females average age 39,1 for the males and 60 for the females. As a cause was referred in 12 patients the fall, in 3 patients the car crash, in 5 patients the following the removal of osteosynthesis materials, in 2 patients the bone cysts, in 1 patient fracture of ankle joint following fusion and in 1 patient a pseudarthrosis. The implantation of DBM concerned 8 hips, 4 femurs, 6 knees, 1 humerus, 1 forearm, 1 ankle, 2 metacarpal and 1 phalanx. All the fractures as well the fusion were treated through internal fixation. There was a regular post op follow-up and concerned the clinical and x-ray examination per month until the total incorporation of the graft (12 weeks). Results: In all patients the total incorporation of the DBM was accomplished in a brief period of time, depended on the place of implantation without having local or systemic side effects. We have to remark the early signs of bone shadow around the 3rd week, as well the incorporation of the matrix around the 12th week in the x-ray findings. Conclusions: The use of DBM in bone defects could play an important role to the filling of bone defrects due to fractures or benign cysts as a result of its incorporation and without inducing local or systematic side effects.

Aims: The effectiveness of the local treatment of experimental osteomyelitis by MRSA with a mixture of calcium phosphate bone cement and 3% teicoplanin into the femur of rabbits. Methods: Thirty-six male rabbits with chronic (3 weeks) MRSA (Methicillin Resistant Staph. aureus) osteomyelitis of the right femur (Model of Norden CW) were treated with a new local Teico-planin delivery system prepared by a mixture of calcium phosphate cement plus 3% teicoplanin. Osteomyelitis was introduced by inoculating 107 cfu/ml of the MRSA strain in a 2mm hole of the bone medula, placement of a needle serving as a foreign body and subsequent closure with a sterile bone wax. The follow-up of the infection was performed by clinical, microbiological, x-rays and histological þndings. On the third week all animals were reoperated and the needle was removed followed by implantation of the above mixture. One control and þve treated animals were sacriþced each week thereafter until the sixth week. Results: Cultures of the treated animals were positive during the þrst week but turned negative after the second week, while throughout the same period cultures from the controls remain positive. Clinical and histologic studies were in accordance. Conclusions: The above mixture could be approved as a supplementary method in the treatment of bone infections. It can be used by replacing the gentamycin polymethyl-methacrylate beads whose use demands reoperation to be removed. Finally it offers the possibility to contribute to the þlling of the bone gaps as it can be replaced by host bone.

Aims: The evaluation of the results becoming from the use of demineralized bone matrix (DBM) in the bone defects.

Methods: In the present study the above substance was implanted during the period 2000–2002 (28 months) to 24 patients, 11 males and 13 females average age 39.1 for the males and 60 for the females. As a cause was referred in 12 patients the fall, in 3 patients the car crash, in 5 patients following the removal of osteosynthesis materials, in 2 patients the bone cysts, in 1 patient fracture of ankle joint following fusion and in 1 patient a pseudarthrosis. The implantation of DBM concerned 8 hips, 4 femurs, 6 knees, 1 humerus, 1 forearm, 1 ankle, 2 metacarpal and 1 phalanx. All the fractures as well the fusion were treated through internal fixation. There was a regular post op follow-up and concerned the clinical and x-ray examination per month until the total incorporation of the graft (12 weeks).

Results: In all patients the total incorporation of the DBM was accomplished in a brief period of time, depended on the place of implantation without having local or systemic side effects. We have to remark the early signs of bone shadow around the 3rd week, as well the incorporation of the matrix around the 12th week in the x-ray findings.

Conclusions: The use of DBM in bone defects could play an important role to the filling of bone defects due to fractures or benign cysts as a result of its incorporation and without inducing local or systematic side effects.

Purpose: To investigate the accuracy of the MRI of the knee for the detection of injuries of the meniscus, cruciate ligaments and articular cartilage, in comparison with the preoperative clinical examination and intraoperative findings.

Material and methods: During 2002 88 patients underwent surgical arthroscopy in our institution, with the diagnosis of meniscal and or cruciate tear. 56 from these patients had preoperative MRI of the affected knee. The accuracy, sensitivity and specificity of the MRI findings were correlated with the lesions identified during arthroscopy. Furthermore, the predictive value of the preoperative MRI was compared with the preoperative clinical evaluation, as well as definitive intraoperative findings.

Results : The accuracy for tears of the medial, lateral meniscus, anterior and posterior cruciate ligaments and articular cartilage was 81%, 77%, 86%, 98% and 60% respectively. The specificity was 69%, 88%, 89%, 75% and 73% respectively. The positive predictive value was 83%, 81%, 90%, 100% and 53% respectively. Finally, the clinical examination had less reliability in the detection of these injuries.

Conclusions: As seen in this retrospective study the accuracy of the MRI in detecting injuries to the knee is superior to the clinical examination. The arthroscopy still remains the gold standard for definitive diagnosis.

Aims: The experimental application and biomechanical evaluation of a double – bundle ACL reconstructive technique(Ä plasty)

Methods: The reported technique suggests use of a pair of grafts, with common origin and different insertions. Experimental surgery was conducted on 25 porcine knee joints, divided as follows: Group A of 15 joints for the reported technique and group B of 10 joints for a single – bundle technique. Group A was divided in subgroups A1, A2 and A3, depending on different distances between insertion points. For surgery and testing a device was designed, with adaptors serving specimen alignment adjustments. A dial gauge was used for monitoring displacements caused by simulated drawer tests. Tests were carried out at knee flexion angles of 30, 60 and 90 degrees and with the natural ACL intact, ruptured and reconstructed. Measurements of Knee laxity were recorded

Results: In the intact condition, no statistical difference was found between specimens used to compare the two techniques (p-value equals 0,905). Overall, the double – bundle technique provided significantly lower laxity values, than the one – bundle technique (2.0 plus/minus 0.6 mm and 3.4 plus/minus 0.9 mm, respectively, with p – value less than 0.001). Laxity values obtained with the double – bundle technique were significantly lower, when adopting a large distance between insertions (p – value equals 0.016).

Conclusions: As the two techniques were compared on a uniform specimen population, results of in vitro biomechanical testing advocate that the reported double- bundle technique offered ACL reconstructions of superior stability. This is a promising technique which is deserved biggest study in vivo.

Aims: The topographical measurement and representation of the ACL insertion on the tibial plateau, based on a greek population sample.

Methods: Fourty eight tibial plateaus were explanted during TKA surgery in 33 female and 15 male patients (average age of 71.2 yrs) suffering from osteoarthritis and rheumatoid arthritis. By means of a calliper, measurements were conducted in order to determine the dimensions shown. Data were used for a topographical representation.

Conclusions: To the authors’ best knowledge, this is the first such anthropometric study on a greek population and its results provide a confirmation on the relatively wide base of ACL insertion on the tibial plateau. The biomechanical performance of this natural configuration for a full range of motion, is possibly not sufficiently reproduced by conventional ACL reconstruction techniques using just one bundle.