N. Wiegand

Arthroscopic treatment of tibial spine fracture in children with a cannulated Herbert screw

BACKGROUND Avulsion fractures of the anterior tibial intercondylar eminence in childhood are rare and are severe injuries of the knee. Since the injury is equivalent in aetiology with ruptures of the anterior cruciate ligament, the treatment requires anatomic reduction and preservation of the stability of the joint. The aim of the study was to demonstrate our experiences with the arthroscopy-guided Herbert-screw fixation in the treatment of displaced tibial eminence fractures in children. METHODS Between January 2004 and December 2011, a total of eight children were treated surgically with Type II or Type III anterior tibial eminence fractures; another four children with undisplaced, Type I fractures were treated conservatively, applying with cast fixation for 6 weeks. Radiological consolidation, stability and functional outcome were assessed during the follow-up examinations. RESULTS On the 12th postoperative week, we did not find instability in any of the patients by physical examination. There were only minimal differences found in the functional outcome, comparing the conservatively and operatively treated groups (Lysholm functional scale, average scores: Type I: 97, Type II: 95 and Type III: 94 points). The range of motion (ROM) of the injured knees was identical with healthy sides on the postoperative 6th week. CONCLUSIONS Our results indicate that the presented method can successfully be applied in the treatment of displaced tibial spine fractures; providing excellent stability and preserving the function of the injured knee in the short-term.

Examination of the cyclophosphamide-induced polyneuropathy on guinea pig sciatic nerve and gastrocnemius muscle with differential scanning calorimetry

Polyneuropathy is defined as a simultaneous malfunction of several peripheral nerves, which could be a side effect of cancer therapy; however, this is reported to occur rarely and difficult to prove. The purpose of the study was to introduce for the first time the calorimetry in the diagnosis of neuropathy in an experimental animal model. The study was inspired by the forensic investigation of a 53-year-old cancer survival female patient, in whose case the development of polyneuropathy could have been caused by cyclophosphamide therapy. Adult guinea pigs were injected intraperitoneally with the dose of cyclophosphamide that comparable to the human dosage. Animals were euthanized; nerve and muscle samples were analyzed by a SETARAM Micro calorimeter. The denaturation temperatures were measured and the calorimetric enthalpies were calculated based on the areas under thermal absorption curves. The thermal denaturation of the samples decreased and the calorimetric enthalpy increased, depending on the therapeutic cyclophosphamide doses. The nerves were more sensitive to chemotherapy, compared to the muscles. The toxic effects of cyclophosphamide on peripheral nerves and muscles can be measured and analyzed by calorimetry, which effects were found dose dependent.

Reconstruction of the patellar tendon using a Y-shaped flap folded back from the vastus lateralis fascia.

BACKGROUND Neglected and repeated ruptures of the patellar tendon are fortunately an uncommon event. These ruptures are often difficult to repair because they are generally accompanied by contractures of the quadriceps muscle and extensive scar tissue formation, and clinical findings are similar regardless of whether the rupture occurred during or after total knee arthroplasty. In both cases, reconstruction is the treatment. METHODS Here, we present data on reconstruction of the patellar tendon using our own method, which is performed in the following manner: the fascia flap shafted in the distal direction is separated from the vastus lateralis fascia of the quadriceps muscle, then folded back and fixed to the tibial tuberosity enclosing the patella in a Y shape. We used this new method in sixteen cases. All of the patients were examined clinically for an average of twenty-eight months. The Knee Society score was determined prior to surgery and on follow up. RESULTS Both the physical and ultrasound monitoring showed that all sixteen tendons healed properly, indicating that there was no need for any further surgical interventions. The mean Knee Society pain and function scores as well as the average range of motion of the knee increased significantly after the operations. CONCLUSION We believe that the presented method is an acceptable option for functional and biomechanical repair of the patellar tendon for the following reasons: the static balance of the knee joint remains unaltered, the quadriceps muscle is not damaged, and the central pulling direction remains steady.

DSC analysis of human synovial fluid samples in the diagnostics of non-septic and septic arthritis

The synovial fluid analysis is an important method in diagnosing and managing septic arthritis. To reach a quick diagnosis, preferably faster than the microbiological cultures, could be a great advantage in the therapy. The differential scanning calorimetry (DSC) has recently been found useful in the differential diagnosis of septic and non-septic periprosthetic conditions. The aim of this study was to evaluate whether there is a specific pattern in the different grades of arthritis, and the effect of three different bacterial strains inoculated in synovial fluid. The sensitivity of our method was also determined by using synovial fluid samples with the different bacterial concentrations. Authors developed a standardized, experimental model to assess the denaturation characteristics of non-septic and inoculated synovial fluid, infected by different bacterial strains. The thermal characteristics [maximal denaturation temperature (Tm) and calorimetric enthalpy change (ΔHcal)] were monitored by SETARAM Micro DSC-II calorimeter. The denaturation scans clearly demonstrated specific, representative curves in the case of different grades of arthritis, as well as with each individual bacterial strain. Therefore, thermoanalyses of human synovial fluid samples by DSC could be a useful tool in the staging of osteoarthritis and the diagnostics of septic arthritis.

The Effect of Neuronal Growth Factor on the Early Recovery After Experimental Sciatic Nerve Defect in Rabbits

Objective/Hypothesis: The facilitation of early functional recovery after peripheral nerve damage is a key component in the treatment of severe nerve traumas. The regeneration of peripheral nerves is determined by multiple factors. The nerve growth factor (NGF) plays an important role in the recovery process by facilitating the Schwann cell proliferation and helping to prepare the reception of the regenerating axon. The purpose of the study was to evaluate the rate of early nerve regeneration in the presence or absence of NGF treatment, using either silicon tubes or autolog veins as a bridge for the neuron defect in a rabbit model of nerve injury. Materials and Methods: White Canadian rabbits were used in the study. Animals were divided into 4 groups (n = 10 in each group). Under general anesthesia, 1 cm long part of the sciatic nerve was removed and the ends were connected with either silicon tube or autolog vein. In case of 10-10 rabbits, NGF was added into the connecting tubes or veins. For another 10-10 rabbits (Control animals), only plasma was added. Electrophysiological examination was performed 2, 4, 6, and 8 weeks following surgery. Histological examination was done on the postoperative second, fourth, and sixth week on 2-2 animals and on the postoperative eighth week on 4-4 animals. Results: The regeneration analyzes demonstrated that the NGF-treated nerves had already become more mature and organized by the postoperative fourth week. The rest of the fibers were still demyelinated; however, there were more myelinated fibers in the NGF-treated group. On the sixth week, the regenerated parts formed into small fascicules, showing a diffuse pattern of myelinated and demyelinated fibers. On the eighth week, the fascicules were strengthened with the signs of longitudinal vascularization. We found significantly higher number of myelinated fibers in the NGF containing tubes, compared with the Controls. Conclusion: Here, we demonstrated that the NGF-treated regenerating nerves show more maturity and neuronal organization on the fourth and sixth week, compared with the Control groups. This effect could facilitate the early functional recovery after peripheral nerve injuries. While NGF has a significant effect on the early regeneration of the rabbit sciatic nerve, based on our results, the endogen NGF has no significant effect on the late nerve regeneration process.