Dan mon O'Dey

CatWalk gait analysis in assessment of functional recovery after sciatic nerve injury.

Following peripheral nerve injury repair, improved behavioural outcome may be the most important evidence of functionality of axon regeneration after any repair strategy. A range of behavioural testing paradigms have been developed for peripheral nerve injury research. Complete injury of the adult rat sciatic nerve is frequently used in combination with walking track analysis. Despite its wide-spread use, these walking track analyses are unsuitable for the simultaneous assessment of both dynamic and static gait parameters. Conversely, a novel automated gait analysis system, i.e. CatWalk can simultaneously measure dynamic as well as static gait parameters and, importantly, its easy to control for the speed of locomotion which can strongly affect gait parameters. In a previous study, CatWalk was already successfully used to examine deficits in both dynamic and static gait parameters using the sciatic nerve lesion model with a 1cm gap characterized by absence of recovery [Deumens R, Jaken RJ, Marcus MA, Joosten EA. The CatWalk gait analysis in assessment of both dynamic and static gait changes after adult rat sciatic nerve resection. J Neurosci Methods 2007;164:120-30]. Using the sciatic nerve crush injury model (validated with the static sciatic index) and a follow-up period of 12 weeks, we now show that CatWalk can also measure behavioural recovery. In particular dynamic gait parameters, coordination measures, and the intensity of paw prints are of interest in detecting recovery as far as these parameters completely return to pre-operative values after crush injury. We conclude that CatWalk can be used as a complementary approach to other behavioural testing paradigms to assess clinically relevant behavioural benefits, with a main advantage that CatWalk demonstrates both static and dynamic gait parameters at the same time.

The role of microstructured and interconnected pore channels in a collagen-based nerve guide on axonal regeneration in peripheral nerves.

The use of bioengineered nerve guides as alternatives for autologous nerve transplantation (ANT) is a promising strategy for the repair of peripheral nerve defects. In the present investigation, we present a collagen-based micro-structured nerve guide (Perimaix) for the repair of 2 cm rat sciatic nerve defects. Perimaix is an open-porous biodegradable nerve guide containing continuous, longitudinally orientated channels for orientated nerve growth. The effects of these nerve guides on axon regeneration by six weeks after implantation have been compared with those of ANT. Investigation of the regenerated sciatic nerve indicated that Perimaix strongly supported directed axon regeneration. When seeded with cultivated rat Schwann cells (SC), the Perimaix nerve guide was found to be almost as supportive of axon regeneration as ANT. The use of SC from transgenic green-fluorescent-protein (GFP) rats allowed us to detect the viability of donor SC at 1 week and 6 weeks after transplantation. The GFP-positive SC were aligned in a columnar fashion within the longitudinally orientated micro-channels. This cellular arrangement was not only observed prior to implantation, but also at one week and 6 weeks after implantation. It may be concluded that Perimaix nerve guides hold great promise for the repair of peripheral nerve defects.

Accidental burns during surgery

The purpose of this report is to increase awareness of intraoperative burns during standard procedures, to discuss their possible causes and warning signs and to provide recommendations for prevention and procedures to follow after their occurrence. A total of 19 patients associated with intraoperative burn accidents were treated surgically and analyzed after a mean follow-up of 5 ± 3.5 months. Review included retrospective patient chart analysis, clinical examination, and technical device and equipment testing. A total of 15 patients recently underwent cardiac surgery, and 4 pediatric patients recovered after standard surgical procedures. A total of 15 patients had superficial and 4 presented with deep dermal or full-thickness burns. The average injured TBSA was 2.1 ± 1% (range, 0.5–4%). Delay between primary surgery and consultation of plastic surgeons was 4.5 ± 3.4 days. A total of 44% required surgery, including débridment, skin grafting or musculocutaneous gluteus maximus flaps, and the remaining patients were treated conservatively. Successful durable soft-tissue coverage of the burn region was achieved in 18 patients, and 1 patient died after a course of pneumonia. Technical analysis demonstrated one malfunctioning electrosurgical device, one incorrect positioned neutral electrode, three incidents occurred after moisture under the negative electrode, eight burns occurred during surgery while fluid or blood created alternate current pathways, five accidents were chemical burns after skin preparation with Betadine solution, and in one case, the cause was not clear. The surgical team should pay more attention to the probability of burns during surgery. Early patient examination and immediate involvement of plastic and burn surgeons may prevent further complications or ease handling after the occurrence.

Aspects of static and dynamic motor function in peripheral nerve regeneration: SSI and CatWalk gait analysis.

Assessment of the therapeutic potential of interventions to bridge-repair peripheral nerve defects heavily relies on the demonstration of improved functional outcome. In the present study we used CatWalk gait analysis (locomotor-test) and Static Sciatic Index (SSI) (static-toe-spread-test) to assess the behavioural benefits of autologous nerve transplantation (ANT) repair of 2-cm rat sciatic nerve defects (neurotmesis-lesion). A reproducible and standardised rat sciatic nerve crush lesion model (axonotmesis-lesion) was used to assess the extent of recovery supported by maximal axon regeneration (measured by SSI and CatWalk). Animals were behaviourally followed for a period of 10 weeks. SSI analysis showed that ANT induced a significant improvement in motor deficit from about -95 to -65, however, CatWalk analysis did not show any major indication of locomotor recovery. This discrepancy might suggest that improvements in static motor functions (such as toe spreading) could reflect an early indicator for the recovery of function. We also noted differences in axon regeneration including increased axon density, smaller axon diameters and thinner myelin sheaths in the distal region of the ANT in comparison to the equivalent region of crushed and normal nerves. This difference in axon regeneration may be related to the clearly improved toe spreading function. We conclude that SSI and CatWalk present different advantages and disadvantages for the assessment of motor recovery after bridge-repair of peripheral nerve defects.

The anterior Obturator Artery Perforator (aOAP) flap: surgical anatomy and application of a method for vulvar reconstruction.

OBJECTIVE Vulvar reconstruction following oncologic resection is challenging. Some flaps used for reconstruction can show adverse characteristics such as excessive tissue bulk or increased distance to the defect. Region of the sulcus genitofemoralis is of thin and pliable tissue proximate to the vulva. Vasculature and suitability of that region used for vulvar reconstruction were focused in this work. METHODS Vascular architecture of the region comprising the sulcus genitofemoralis was examined bilaterally on 10 female corpses (n = 20 specimens). In addition, tissue characteristics and suitability of that region to form a fasciocutaneous flap for vulvar reconstruction were anatomically examined and clinically proven. RESULTS Vasculature of the sulcus genitofemoralis is reflected by either a musculocutaneous perforator (80%, 16/20) piercing the gracilis muscle or a septocutaneous perforator (20%, 4/20) passing the posterior border of the gracilis muscle 1.3 ± 0.3 [cm] laterally to the inferior pubic ramus. Both types of perforators derive from the anterior branch of the obturator artery and accompanying vein. This perforator, the anterior obturator artery perforator (aOAP), supplies a skin territory of about 7 × 15 [cm] centered on the sulcus genitofemoralis. The aOAP flap proved its suitability and versatility for vulvar reconstruction. CONCLUSIONS The sulcus genitofemoralis is of a constant vascular anatomy reflected by the aOAP vessel. Especially the tunneled aOAP island flap offers outstanding characteristics beneficial for reconstruction of a more anatomically normal vulva. Scars are limited within anatomic borders of the urogenital region improving self-image. The aOAP flap clearly enlarges the surgical options available to restore the form and function of the vulva.

Ablative targeting of fatty-tissue using a high-powered diode laser.

Concerning current clinical practice, laser‐assisted lipoplasty is still secondary to other procedures. In order to evaluate effects of thermal interaction with fatty‐tissue, a near infrared diode laser was examined under reproducible conditions.

The Proximal Medial Sural Nerve Biopsy Model: A Standardised and Reproducible Baseline Clinical Model for the Translational Evaluation of Bioengineered Nerve Guides

Autologous nerve transplantation (ANT) is the clinical gold standard for the reconstruction of peripheral nerve defects. A large number of bioengineered nerve guides have been tested under laboratory conditions as an alternative to the ANT. The step from experimental studies to the implementation of the device in the clinical setting is often substantial and the outcome is unpredictable. This is mainly linked to the heterogeneity of clinical peripheral nerve injuries, which is very different from standardized animal studies. In search of a reproducible human model for the implantation of bioengineered nerve guides, we propose the reconstruction of sural nerve defects after routine nerve biopsy as a first or baseline study. Our concept uses the medial sural nerve of patients undergoing diagnostic nerve biopsy (≥2 cm). The biopsy-induced nerve gap was immediately reconstructed by implantation of the novel microstructured nerve guide, Neuromaix, as part of an ongoing first-in-human study. Here we present (i) a detailed list of inclusion and exclusion criteria, (ii) a detailed description of the surgical procedure, and (iii) a follow-up concept with multimodal sensory evaluation techniques. The proximal medial sural nerve biopsy model can serve as a preliminarynature of the injuries or baseline nerve lesion model. In a subsequent step, newly developed nerve guides could be tested in more unpredictable and challenging clinical peripheral nerve lesions (e.g., following trauma) which have reduced comparability due to the different nature of the injuries (e.g., site of injury and length of nerve gap).

Variants of the supplying vessels of the vascularized iliac bone graft and their relationship to important surgical landmarks

The iliac bone crest is one of the most valuable regions for harvesting bone grafts, both vascularized and nonvascularized. Since the first commendable description of this region as a possible source for vascularized bone flaps by Taylor, little relevant information concerning the variations of the deep circumflex iliac vessels and their relationship to the neighboring structures has been published. The purpose of the current study was to examine this region clinically and anatomically, taking into consideration the former description by Taylor. We gathered all our findings on 216 iliac regions and proposed a new classification. In addition we measured the relationships between the deep circumflex iliac artery and important surgical landmarks. A comparison of our finding with other studies showed similarities and differences but was far more complete. Generally (92%) the deep circumflex iliac artery (DCIA) originated from external iliac artery (EIA) behind the inguinal ligament (IL) and passed cranio‐laterally toward the anterior superior iliac spine, where it divided into two important branches. Four variations were observed of the DCIA. The deep circumflex iliac vein (DCIV) ran over (82.5%) or under (17.5%) the EIA. The superficial circumflex iliac vein (SCIV) was observed draining into the DCIV in some dissections. Three different variations of the superficial circumflex iliac artery (SCIA) were observed. The anatomical knowledge of these variations and their correlation to important surgical landmarks can help in harvesting the DCIA flap more safely and thus increasing the success rate while reducing donor site morbidity. Clin. Anat., 2013.

Common peroneal nerve compression and heterotopic ossification resulting from severe burn injury: a case report.

Heterotopic ossification is defined as the abnormal location of lamellar bone within soft tissue, where bone normally does not exist1. Despite various theories, the exact mechanism (etiology and pathogenesis) of heterotopic ossification remains uncertain2. Johnson first described heterotopic ossification in patients with burn injuries in 19573, but thermal injury has been reported to be one of the least common causes of heterotopic ossification, with an estimated prevalence of 1% to 3% of all patients with burn injuries1,4-6. The most common location of heterotopic ossification in patients who have sustained a burn injury appears to be the elbow, leading to stiffness and contracture; far lower rates have been reported in other regions5,7-13. Lesions of peripheral nerves as a complication of heterotopic ossification are a relatively rare phenomenon and mainly consist of compression of the ulnar nerve in the elbow region4,5,14,15. The common peroneal nerve follows a curved course, lateral to the fibular neck, and then runs deep to the peroneus longus muscle, where it divides into the superficial and deep peroneal nerves16,17. The entrance into the fibular tunnel is a musculo-aponeurotic arch, derived from the soleus and peroneus longus muscles, called the fibrous arch 18. It is believed that peroneal nerve entrapment or fibular tunnel syndrome, which has been described on occasion in the literature, is caused by this fibrous arch16,17. To the best of our knowledge, there is only one well-documented report of heterotopic ossification in combination with a lesion of the common peroneal nerve19, but an associated entrapment of the nerve by this fibrous arch or other altered connective tissue was not …

[Heated car seats--a potential burn risk for paraplegics].

The comfort of heated car seats has gained popularity worldwide. We present a rare case of severe second- and third-degree burn in the lower back and sacral region of a 42-year-old post-traumatic paraplegic patient while using a heated car seat. The patient was admitted to our burn unit and required several reconstructive surgery procedures. Inadvertent thermal injury is a constant potential hazard for individuals with impaired sensibility such as paraplegics and other neurologically impaired patients. Early education of patients, manufacturers, and health care personnel is of eminent importance to prevent severe burn injuries in this risk population.ZusammenfassungBeheizte Autositze werden mit steigender Popularität in Anspruch genommen. Wir stellen den klinischen Fall einer schweren zweit- und drittgradigen Verbrennung der Sakroglutealregion eines 42-jährigen posttraumatisch Querschnittsgelähmten vor. Der Patient wurde in unserer Verbrennungsklinik aufgenommen und zahlreiche Operationen wurden notwendig. Querschnittsgelähmte Patienten sind durch ihre Sensibilitäts- und Schmerzempfindungsstörung einem erhöhten Verbrennungsrisiko durch Autositzheizungen ausgesetzt. Wir empfehlen eine frühzeitige adäquate Aufklärung der Patienten, Hersteller und aller Bezugspersonen zur Vermeidung derartig schwerwiegender Verbrennungsereignisse.SummaryThe comfort of heated car seats has gained popularity worldwide. We present a rare case of severe second- and third-degree burn in the lower back and sacral region of a 42-year-old post-traumatic paraplegic patient while using a heated car seat. The patient was admitted to our burn unit and required several reconstructive surgery procedures. Inadvertent thermal injury is a constant potential hazard for individuals with impaired sensibility such as paraplegics and other neurologically impaired patients. Early education of patients, manufacturers, and health care personnel is of eminent importance to prevent severe burn injuries in this risk population.