OBJECTIVE Multiple factors may affect functional recovery after peripheral nerve injury, among them the lesion site and the interval between the injury and the surgical repair. When the nerve segment distal to the lesion site undergoes chronic degeneration, the ensuing regeneration (when allowed) is often poor. The aims of the current study were as follows: 1) to examine the expression changes of the neuregulin 1/ErbB system during long-term nerve degeneration; and 2) to investigate whether a chronically denervated distal nerve stump can sustain nerve regeneration of freshly axotomized axons. METHODS This study used a rat surgical model of delayed nerve repair consisting of a cross suture between the chronically degenerated median nerve distal stump and the freshly axotomized ulnar proximal stump. Before the suture, a segment of long-term degenerated median nerve stump was harvested for analysis. Functional, morphological, morphometric, and biomolecular analyses were performed. RESULTS The results showed that neuregulin 1 is highly downregulated after chronic degeneration, as well as some Schwann cell markers, demonstrating that these cells undergo atrophy, which was also confirmed by ultrastructural analysis. After delayed nerve repair, it was observed that chronic degeneration of the distal nerve stump compromises nerve regeneration in terms of functional recovery, as well as the number and size of regenerated myelinated fibers. Moreover, neuregulin 1 is still downregulated after delayed regeneration. CONCLUSIONS The poor outcome after delayed nerve regeneration might be explained by Schwann cell impairment and the consequent ineffective support for nerve regeneration. Understanding the molecular and biological changes occurring both in the chronically degenerating nerve and in the delayed nerve repair may be useful to the development of new strategies to promote nerve regeneration. The results suggest that neuregulin 1 has an important role in Schwann cell activity after denervation, indicating that its manipulation might be a good strategy for improving outcome after delayed nerve repair.
Purpose To investigate the long-term effectiveness and safety of botulinum neurotoxin A (BoNT-A) treatment in patients with blepharospasm (BEB), hemifacial spasm (HFS), and entropion (EN) and to use for the first time two modified indexes, 'botulin toxin escalation index-U' (BEI-U) and 'botulin toxin escalation index percentage' (BEI-%), in the dose-escalation evaluation. Methods All patients in this multicentre study were followed for at least 10 years and main outcomes were clinical efficacy, duration of relief, BEI-U and BEI-%, and frequency of adverse events. Results BEB, HFS, and EN patients received a mean BoNT-A dose with a significant intergroup difference (Po0.0005, respectively). The mean ( ± SD) effect duration was statistically different (P ¼ 0.009) among three patient groups. Regarding the BoNT-A escalation indexes, the mean ( ± SD) values of BEI-U and BEI-% were statistically different (P ¼ 0.035 and 0.047, respectively) among the three groups. In BEB patients, the BEI-% was significantly increased in younger compared with older patients (P ¼ 0.008). The most frequent adverse events were upper lid ptosis, diplopia, ecchymosis, and localized bruising. Conclusions This long-term multicentre study supports a high efficacy and good safety profile of BoNT-A for treatment of BEB, HFS, and EN. The BEI indexes indicate a significantly greater BoNT-A-dose escalation for BEB patients compared with HFS or EN patients and a significantly greater BEI-% in younger vs older BEB patients. These results confirm a greater efficacy in the elderly and provide a framework for long-term studies with a more flexible and reliable evaluation of drug-dose escalation.
Application of the algorithm described has led to a significant reduction in RFF donor site complication rates. This demonstrates that if flap donor sites are analyzed and tailor treated in the same way as primary defects are, instead of being given secondary importance and just grafted, outcomes improve.
Peripheral nerve injuries are a heterogeneous group of lesions that may occurs secondary to\ud various causes. Several different classifications have been used to describe the pathophysiological\ud mechanisms leading to the clinical deficit, from simple and reversible compression‑induced\ud demyelination, to complete transection of nerve axons. Neurophysiological data localize, quantify,\ud and qualify (demyelination vs. axonal loss) the clinical and subclinical deficits. High‑resolution\ud ultrasound can demonstrate the morphological extent of nerve damage, fascicular echotexture\ud (epineurium vs. perineurium, focal alteration of the cross‑section of the nerve, any neuromas, etc.),\ud and the surrounding tissues. High field magnetic resonance imaging provides high contrast\ud neurography by fat suppression sequences and shows structural connectivity through the use\ud of diffusion‑weighted sequences. The aim of this review is to provide clinical guidelines for the\ud diagnosis of nerve injuries, and the rationale for instrumental evaluation in the preoperative and\ud postoperative periods. While history and clinical approach guide neurophysiological examination,\ud nerve conduction and electromyography studies provide functional information on conduction\ud slowing and denervation to assist in monitoring the onset of re‑innervation. High‑resolution nerve\ud imaging complements neurophysiological data and allows direct visualization of the nerve injury\ud while providing insight into its cause and facilitating surgical treatment planning. Indications and\ud limits of each instrumental examination are discussed
).Shortening or absence of the distal fibula may cause a clinically valgus hindfoot owing to the talar abduction and lateral rotation.1,2 A displacement of 1 mm or 30-degree lateral rotation could alter the load distribution and lead to an abnormal articular stress causing subsequent arthritis. 3-5In case of loss of both bone and soft tissue, a reconstructive treatment is mandatory in order to restore skin coverage and a functional ankle with long-term stability.We present two results of a one-stage reconstruction of the complex lateral malleolus traumatic defect with two different microsurgical composite compound flaps. Patients and Method Case 1A 25-year-old man with a subtotal defect of the left lateral malleolus and a 10 Â 6 cm skin defect because of a motorbike accident was treated with a combined iliac crest bone and iliacus muscle flap plus a split-thickness skin graft, revascularized in an end-to-end fashion on the peroneal vessels.Two screws were used to lock the iliac graft and reconstruct the tibiofibular syndesmosis (TFS). This decision was made intraoperatively because of impairment of ligamentous structures and instability of the ankle. Screws were removed 90 days after the procedure.At 5-month control, magnetic resonance imaging (MRI) showed good morphology of the articular surface of the ankle joint. At 13-year control, X-ray images showed a tibiofibular arthrodesis and no signs of arthritis with a flexo-extension of the tibiotalar joint comparable to the contralateral one (►Figs. 1 and 2). Case 2An 11-year-old girl presented a traumatic defect of partial left lateral malleolus with an associated 12 Â 22 cm skin defect, as a result of a car accident. We performed a free combined serratus muscle and ninth rib bone flap plus a split-thickness skin graft, revascularized in an end-to-end fashion on the anterior tibial vessels. Plate was employed to give stability and external support, thereby allowing an early mobilization.The plate and screws were removed on day 180. Clinical control showed good mobility and stability of the ankle. The flap was too bulky, and required secondary liposuction to improve the cosmetic result.At 7-year follow-up, X-ray images showed a well-integrated rib with a restored continuity of the bone and preservation of TFS. Plantar flexion of the ankle was 50 degrees and dorsal flexion 10 degrees (►Figs. 3 and 4). DiscussionLoss of tissue in the foot and ankle region represents a challenging problem because of the small number of local flaps available close to the structures involved in walking and load bearing.In case 1, as the tibiofibular ligaments were severely damaged, we fixed the bone with screws passing through three cortical structures for a tighter reconstruction to perform a tibiofibular arthrodesis leaving the tibiotalar joint free. The function and mobility of the ankle were good, and the patient did not experience any problems from the procedure in his daily life.In case 2, we proposed to perform bone synthesis with plate and screws, which would then be removed lat...
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