Marcela Fernandes

Bone marrow cells are able to increase vessels number during repair of sciatic nerve lesion

The aim of this study was to compare the outcomes of nerve autografts (GRF) and venous grafts containing mononuclear bone marrow cells (BMCs) in sciatic nerve-lesioned rats. Control animals underwent sham operations (SHAM), received empty venous grafts (EPV), or received venous grafts containing BMC vehicle (AGR). Outcome was evaluated through sciatic functional index (SFI), morphometric and morphologic analyses of the nerve distal to the lesion, and the number of spinal cord motor neurons positive for the retrograde tracer, Fluoro-Gold. All groups exhibited poor results in SFI when compared to SHAM animals throughout the postoperative period. All groups also had a significantly greater fiber density, decreased fiber diameter, and decreased motor neuron number than the SHAM group. No significant difference between the GRF and BMC groups was observed in any of these parameters. On the other hand, vessel density was significantly higher in BMC than all other groups. BMC-containing venous grafts are superior to nerve autografts in increasing vessel density during sciatic nerve regeneration.

Peripheral nerve regeneration with conduits: use of vein tubes.

Treatment of peripheral nerve injuries remains a challenge to modern medicine due to the complexity of the neurobiological nerve regenerating process. There is a greater challenge when the transected nerve ends are not amenable to primary end-to-end tensionless neurorraphy. When facing a segmental nerve defect, great effort has been made to develop an alternative to the autologous nerve graft in order to circumvent morbidity at donor site, such as neuroma formation, scarring and permanent loss of function. Tubolization techniques have been developed to bridge nerve gaps and have been extensively studied in numerous experimental and clinical trials. The use of a conduit intends to act as a vehicle for moderation and modulation of the cellular and molecular ambience for nerve regeneration. Among several conduits, vein tubes were validated for clinical application with improving outcomes over the years. This article aims to address the investigation and treatment of segmental nerve injury and draw the current panorama on the use of vein tubes as an autogenous nerve conduit.

Nerve Regeneration: Is There an Alternative to Nervous Graft?

BACKGROUND In nerve injury with nervous gap, no restitution method was found better than the autograft, however, it has the disadvantage of damaging a normal nerve to be used as a graft. Platelet-rich plasma (PRP) is a possible filler material for vein grafts used as conduits for nerve regeneration, preventing its collapse, and providing growth factors and osteoconductive proteins. METHODS Isogenic rats were randomly divided into three groups. They received nerve autografts (GRF), PRP-containing vein grafts or a sham operation. Outcomes were evaluated by the sciatic functional index (SFI), morphometric, and morphologic analyses of the nerve distal to the lesion, and the number of spinal cord motoneurons positive for retrograde Fluoro-Gold (Santa Cruz Biotechnology, Inc., Dallas, TX) tracer. RESULTS The PRP and GRF groups had lower SFI values than the control animals throughout the postoperative period. The SFI was significantly higher in the PRP group than the GRF group at 90 days postoperatively (p = 0.011). Fiber diameter and number of motoneurons were significantly decreased in both the PRP and GRF groups, as compared with the control. CONCLUSION PRP within a vein conduit may be an effective alternative or adjuvant to GRF, the current preferred treatment for nerve injury with a nerve gap, and further investigations are required to fully define the role of PRP in nerve regeneration.

Estudo da regeneração de nervos tibiais de ratos Wistar em sutura primária com "gap" e sem "gap", cobertos por segmentos de veia

Objective This study compared nerve regeneration in Wistar rats, using epineural neurorrhaphy with a gap of 1.0 mm and without a gap, both wrapped with jugular vein tubes. Motor neurons in the spinal cord between L3 and S1 were used for the count, marked by exposure of the tibial nerve to Fluoro-Gold (FG). Method The tibial nerves on both sides were cut and sutured, with a gap on one side and no gap in the other. The sutures were wrapped with a jugular vein. Four months after surgery the tibial nerves were exposed to Fluoro-Gold and the motor neuron count performed in the spinal cord. Results The results were statistically analyzed by the paired Wilcoxon test. There was a statistical difference between the groups with and without gap in relation to the motor neuron count (p=0.013). Conclusion The epineural neurorraphy without gap wrapped with jugular vein showed better results for nerve regeneration than the same procedure with gap. Level of Evidence: Experimental Study.OBJECTIVE: This study compared nerve regeneration in Wistar rats, using epineural neurorrhaphy with a gap of 1.0 mm and without a gap, both wrapped with jugular vein tubes. Motor neurons in the spinal cord between L3 and S1 were used for the count, marked by exposure of the tibial nerve to Fluoro-Gold (FG). METHOD: The tibial nerves on both sides were cut and sutured, with a gap on one side and no gap in the other. The sutures were wrapped with a jugular vein. Four months after surgery the tibial nerves were exposed to Fluoro-Gold and the motor neuron count performed in the spinal cord. RESULTS: The results were statistically analyzed by the paired Wilcoxon test. There was a statistical difference between the groups with and without gap in relation to the motor neuron count (p=0.013). CONCLUSION: The epineural neurorraphy without gap wrapped with jugular vein showed better results for nerve regeneration than the same procedure with gap. Level of Evidence: Experimental Study.

Bone marrow-derived mesenchymal stem cells versus adipose-derived mesenchymal stem cells for peripheral nerve regeneration

Studies have confirmed that bone marrow-derived mesenchymal stem cells (MSCs) can be used for treatment of several nervous system diseases. However, isolation of bone marrow-derived MSCs (BMSCs) is an invasive and painful process and the yield is very low. Therefore, there is a need to search for other alterative stem cell sources. Adipose-derived MSCs (ADSCs) have phenotypic and gene expression profiles similar to those of BMSCs. The production of ADSCs is greater than that of BMSCs, and ADSCs proliferate faster than BMSCs. To compare the effects of venous grafts containing BMSCs or ADSCs on sciatic nerve injury, in this study, rats were randomly divided into four groups: sham (only sciatic nerve exposed), Matrigel (MG; sciatic nerve injury + intravenous transplantation of MG vehicle), ADSCs (sciatic nerve injury + intravenous MG containing ADSCs), and BMSCs (sciatic nerve injury + intravenous MG containing BMSCs) groups. Sciatic functional index was calculated to evaluate the function of injured sciatic nerve. Morphologic characteristics of nerves distal to the lesion were observed by toluidine blue staining. Spinal motor neurons labeled with Fluoro-Gold were quantitatively assessed. Compared with sham-operated rats, sciatic functional index was lower, the density of small-diameter fibers was significantly increased, and the number of motor neurons significantly decreased in rats with sciatic nerve injury. Neither ADSCs nor BMSCs significantly improved the sciatic nerve function of rats with sciatic nerve injury, increased fiber density, fiber diameters, axonal diameters, myelin sheath thickness, and G ratios (axonal diameter/fiber diameter ratios) in the sciatic nerve distal to the lesion site. There was no significant difference in the number of spinal motor neurons among ADSCs, BMSCs and MG groups. These results suggest that neither BMSCs nor ADSCs provide satisfactory results for peripheral nerve repair when using MG as the conductor for engraftment.

Intra-individual evaluation of results between open and endoscopic release in bilateral carpal tunnel syndrome

Objective The authors performed an intra-individual comparison of surgical results between the open and endoscopic surgical techniques in patients with bilateral carpal tunnel syndrome. Each hand was submitted to surgery using one of these techniques. Methods Fifteen patients (30 hands) were evaluated by the Boston Questionnaire, visual analogue pain scale, palmar grip strength, and for tip, key, and tripod pinch strengths. These measurements were taken before surgery and at two weeks, one month, three months, and six months after the procedure. Scores for each evaluation tool in each evaluation time period were compared. Results In comparison to the group submitted to open surgery, the group submitted to endoscopic surgery had worse scores in the evaluation of the 1st and 6th postoperative months regarding the severity of the symptoms. The authors found no differences in the functional status of the hand. Regarding the intensity of pain evaluated by the visual analogue pain scale, no difference was found between the averages in all time periods evaluated. No differences in palmar grip strength and in fingertip, key (lateral), and tripod pinch strengths were found in all time periods. There were no differences between averages in the preoperative period at two weeks, one month, and three months after surgery. After six months, the group of patients submitted to open surgery presented greater tripod force than the group of patients who underwent endoscopic surgery. Conclusion No differences were observed by using the intra-individual evaluation in the results between open and endoscopic techniques for the treatment of carpal tunnel syndrome.

Arthroscopic Resection of Dorsal Wrist Ganglion: Results and Rate of Recurrence Over a Minimum Follow-up of 4 Years

Background: Dorsal wrist ganglia are the most common soft tissue tumor type of the upper limb. Surgical resection, open or arthroscopic, is one of the most frequent procedures performed by hand surgeons. This study sought to perform an objective evaluation of the outcomes of arthroscopic resection of dorsal wrist ganglia and their recurrence rates over 4 years. Patients treated with arthroscopic resection were expected to have favorable outcomes and low complication rates after 4 years of follow-up. Methods: We evaluated 34 cases of dorsal wrist ganglia in patients who underwent arthroscopic resection. The patients were evaluated using the Quick-Disabilities of the Arm, Shoulder and Hand (QuickDASH) outcome measure, visual analog scale (VAS) for pain, range of motion of the wrist, palmar grip strength, rates of recurrence, and complications. Results: During the postoperative period, the QuickDASH score averaged 2.3 points, the mean residual pain by VAS was 0.54, full range of wrist movement was recovered by all patients, and the mean palmar grip strength was 29.4 kgf; there was 1 case with recurrence. There were no severe postoperative complications throughout the follow-up period. Conclusions: The outcomes, recurrence, and complications rates after 4 years of follow-up presented in this study support the use of arthroscopy as a treatment for dorsal wrist ganglion.

Evaluation of Interobserver Agreement in the Albertoni’s Classification for Mallet Finger

Objective: To measure the reliability of Albertoni’s classification for mallet finger. Methods: We performed an evaluation using a questionnaire where there were 43 pictures of radiographs of the distal interphalangeal joint with mallet finger. All lesions were classified by Albertoni’s classification, for a total of 19 respondents (12 hand surgeons and 7 interns). It was then evaluated by the interobserver agreement using the kappa coefficient, separated by groups—(1) tendon avulsion, (2) avulsion fracture, (3) fracture of the dorsal lip, and (4) phisis injury—and subgroups (each group divided into 1 and 2). Results: Agreement was excellent for the group A (k, 0.95 [0.93-0.97]) and remained good when separated into A1 and A2; group B was reasonable (k, 0.42 [0.39-0.44]), and poor when separated into B1 and B2; in the group C, agreement was good (k, 0.72 [0.70-0.74]), but when separated into C1 and C2, it became moderate. In group D, agreement was always bad (k, 0.16 [0.14-0.19]). The general agreement was moderate, with k, 0.57 (0.56-0.58). Conclusion: Albertoni’s classification evaluated for interobserver agreement is considered a reproducible classification by the method used in the research.