Interventional paired associative stimulation (IPAS) to the contralateral peripheral nerve and cerebral cortex can enhance the primary motor cortex (M1) excitability with two synchronously arriving inputs. This study investigated whether dopamine contributed to the associative long-term potentiation-like effect in the M1 in Parkinson's disease (PD) patients. Eighteen right-handed PD patients and 11 right-handed age-matched healthy volunteers were studied. All patients were studied after 12 hours off medication with levodopa replacement (PD-off). Ten patients were also evaluated after medication (PD-on). The IPAS comprised a single electric stimulus to the right median nerve at the wrist and subsequent transcranial magnetic stimulation of the left M1 with an interstimulus interval of 25 milliseconds (240 paired stimuli every 5 seconds for 20 minutes). The motor-evoked potential amplitude in the right abductor pollicis brevis muscle was increased by IPAS in healthy volunteers, but not in PD patients. IPAS did not affect the motor-evoked potential amplitude in the left abductor pollicis brevis. The ratio of the motor-evoked potential amplitude before and after IPAS in PD-off patients increased after dopamine replacement. Thus, dopamine might modulate cortical plasticity in the human M1, which could be related to higher order motor control, including motor learning.

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This study included 25 patients with lower limb tumors who had reconstruction by vascularized fibula osteoseptocutaneous flap performed at least 24 months before the end of the study. Hypertrophy of the transplanted fibula was estimated on serial radiographs by a modification of the formula of De Boer and Wood (J Bone Joint Surg [Br] 71:374-378, 1989). A significant graft was observed in 90% of the patients at an average follow-up of 27 months (range, 30-200%). The time to graft union (start of partial weight-bearing) positively correlated with the time to significant graft hypertrophy (r = 0.9, P < 0.01). The final amount of graft hypertrophy was affected by the age of the patient (P < 0.01) and the length of follow-up (P < 0.05). Graft hypertrophy progressed at an average rate of 3.3% per month (range, 2.3-4.9%) until the end of the 30th month; thereafter, little or no increase in graft hypertrophy was observed. The rate of graft hypertrophy showed two significant peaks at 6-12 months (P < 0.001) and at 18-24 months (P < 0.05). Patients younger than age 20 years showed faster hypertrophy, with a peak at the 12th month. Hypertrophy progressed faster in patients who received chemotherapy until the 12th month, and then declined sharply compared to those who did not receive chemotherapy.

The objective of this study is to estimate the reference values for the lower limb peripheral nerves in adults.The demographics and physical characteristics of 69 adult healthy volunteers were evaluated and recorded. The estimated reference values and their correlations with the age, weight, height, body mass index (BMI) were evaluated.The cross sectional area reference values were obtained at 5 predetermined sites for 3 important lower limb peripheral nerves. Our CSA values correlated significantly with age, weight, and BMI. The normal reference values for each nerve were as follows: Tibial nerve at the popliteal fossa 19 mm2 ± 6.9, tibial nerve at the level of the medial malleolus 12.7 mm2 ± 4.5, common peroneal nerve at the popliteal fossa 9.5 mm2 ± 4, common peroneal nerve fibular head 8.9 mm2 ± 3.2, sural nerve 3.5 mm2 ± 1.4.The reference values for the lower limb peripheral nerves were identified. These values could be used for future management of peripheral nerve disorders.

One hundred nine obstetrical palsy patients with defective shoulder abduction and external rotation had subscapularis release and transfer of teres major to infraspinatus with or without pedicle transfer of the clavicular head of pectoralis major to deltoid. The age at surgery averaged 67 months (11-192) and follow-up averaged 36 months (12-80). Thirty-nine cases had follow-up CT scan of both shoulders. Improvement of abduction averaged 64 degrees and that of external rotation 50 degrees, 100% and 290% gain, respectively. Both negatively correlated with the age at surgery (P < 0.001), and were significantly higher in patients operated younger than 4 years. On computed tomographic scans, the degree of glenoid retroversion positively correlated (P < 0.001) with the age at surgery, and was significantly higher in patients operated older than 4 years. The degree of posterior subluxation showed no significant difference between different ages. There was no significant difference between the operated and normal sides in patients operated younger than 4years with regard to glenoid retroversion and in those operated younger than 2 years with regard to posterior subluxation. The operation is useful for correction of defective shoulder abduction and external rotation in obstetric palsy. It is best performed before the age of 2 to get maximal improvement in motion and prevent secondary bone changes. Between the ages of 2 and 4, it also resulted in significant improvement in motion and prevented glenoid retroversion, but not posterior subluxation. After the age of 4, the improvement in motion was not significant and secondary bone changes were not prevented.

Very limited literature described the use of the free anterolateral thigh (ALT) among other flaps for pediatric lower limb reconstruction. The aim of this study is to present our experience using the free ALT flap for reconstruction of soft tissue defects over the dorsum of the foot and ankle in children. The study included 42 children aged 2.5-13 years with a mean of 6.18 years. Three children had crush injuries while the rest were victims of run over car accidents. All of the flaps were vascularized by at least two perforators; 88.23% were musculocutaneous and 11.77 were septocutaneous perforators. All flaps were raised in a subfascial plane. Initial thinning was performed in five flaps and 35% required subsequent debulking. Mean Flap surface area was 117.11 cm(2). The recipient arteries were the anterior tibial artery in 38 cases and posterior tibial artery in four cases. Venous anastomosis was performed to one vena commitant and in nine cases the long saphenous vein was additionally used. Mean ischemia time of the flap was 2 hours while total operative time averaged 6.3 hours. About 41% of donor sites were closed primarily while 59% required skin grafting. Primary flap survival rate was 92.8% (39/42 cases). Three flaps showed venous congestion. After venous reanastomosis, two flaps showed partial loss and one flap was lost completely. Post-operative hospital stay averaged 7.5 days. The free ALT flap could be as safe, reliable, and aesthetically appealing option for foot/ankle resurfacing in children after traumatic soft tissue loss.

There are several options for the treatment of traumatic tibial defects. Among these options, free vascularized fibula and Ilizarov bone transport are well-known and effective techniques. The differences between both techniques and the indications for each of them are not well studied in the literature. Between September 1995 and December 2004, Ilizarov bone transport and free vascularized fibula were used to treat 25 traumatic bone. Patients were divided into two groups, Ilizarov group (12) and free fibula group (13). Preoperative data, operative data, duration of treatment, functional outcome, range of motion loss, number of secondary procedures, and type and rate of complications were compared in both groups. All the cases were ultimately united in both groups. Operative time and blood loss were significantly higher in the free fibula group. Although external fixation time was longer in the Ilizarov group, the overall duration of treatment was similar. Range of motion loss was less in the Ilizarov group, but the overall functional outcome was similar. There was no difference in complication rate, or number secondary procedures. Defect size was found to have the most significant effect on the results. Results were much better in the free fibula group when the defect length was 12 cm or more while the results were better in Ilizarov group when the defect length was less than 12 cm. We recommend using free vascularized fibula for traumatic tibial defects of 12 cm or more, whenever experience is available.

The objective of this study is to estimate the reference values for the upper limb peripheral nerves in adults.The demographics and physical characteristics of 69 adult healthy volunteers were evaluated and recorded. In addition, the side to side differences of the estimated reference values and their correlations with the age, weight, height, and body mass index (BMI) were evaluated.Cross-sectional area reference values of the upper limb nerves did not correlate with height; however, they correlated with age, weight, and BMI in some scanned sites.The data obtained in this study could be helpful in future diagnosis of peripheral nerve disorders of the upper limb.