Fibrin Glue Coating Limits Scar Tissue Formation around Peripheral Nerves.

Scar tissue formation presents a significant barrier to peripheral nerve recovery in clinical practice. While different experimental methods have been described, there is no clinically available gold standard for its prevention. This study aims to determine the potential of fibrin glue (FG) to limit scarring around peripheral nerves. Thirty rats were divided into three groups: glutaraldehyde-induced sciatic nerve injury treated with FG (GA + FG), sciatic nerve injury with no treatment (GA), and no sciatic nerve injury (Sham). Neural regeneration was assessed with weekly measurements of the visual static sciatic index as a parameter for sciatic nerve function across a 12-week period. After 12 weeks, qualitative and quantitative histological analysis of scar tissue formation was performed. Furthermore, histomorphometric analysis and wet muscle weight analysis were performed after the postoperative observation period. The GA + FG group showed a faster functional recovery (6 versus 9 weeks) compared to the GA group. The FG-treated group showed significantly lower perineural scar tissue formation and significantly higher fiber density, myelin thickness, axon thickness, and myelinated fiber thickness than the GA group. A significantly higher wet muscle weight ratio of the tibialis anterior muscle was found in the GA + FG group compared to the GA group. Our results suggest that applying FG to injured nerves is a promising scar tissue prevention strategy associated with improved regeneration both at the microscopic and at the functional level. Our results can serve as a platform for innovation in the field of perineural regeneration with immense clinical potential.

Comparative analysis of surgical treatment modalities for a popliteal pterygium: a meta-analysis.

INTRODUCTION: Popliteal pterygium syndrome is a rare congenital disorder characterized by orofacial, cutaneous, musculoskeletal, and genital anomalies. The popliteal pterygium (PP) affects ambulation due to severe knee flexion contracture and equinovarus deformities. Surgical treatment aims to correct these deformities while preserving limb sensibility. However, due to its rarity, surgical guidelines are lacking. MATERIALS AND METHODS: A meta-analysis according to PRISMA guidelines was conducted to summarize and compare surgical methods for PP. 183 paper were identified in PubMed and data from 32 articles were analyzed, including patient demographics, treatment modalities (Ilizarov fixator, femoral osteotomy, skin/soft tissue procedures, hamstring release, nerve surgery, and amputation), pre- and post-operative abilities to walk, knee joint parameters, complications, and recurrent contractions. RESULTS: Among 58 patients (87 limbs), Ilizarov fixator demonstrated improved knee and ankle mobility postoperatively, but showed a relatively high surgical session count and complication rates. Femoral osteotomy achieved successful knee posture correction with fewer sessions and no complications. Isolated skin/soft tissue procedures improved flexion contracture and mobility, though they required several procedures. Hamstring release achieved notable contracture reduction but also necessitated multiple interventions. Nerve surgery and amputation had limited data, warranting further investigation. CONCLUSION: The management of PP demands a comprehensive approach, considering individual patient characteristics and treatment outcomes. While different surgical modalities offer distinct benefits, a classification or guideline to treat this deformity is still lacking. Further research is essential to validate findings, refine treatment approaches, and enhance the quality of life for individuals with PP.

Mechanisms, interventions at risk and clinical presentation of iatrogenic nerve lesions in trauma patients.

BACKGROUND: Iatrogenic nerve lesions during surgical interventions are avoidable complications that may cause severe functional impairment. Hereby, awareness of physicians and knowledge of structures and interventions at risk is of utmost importance for prevention. As current literature is scarce, we evaluated all patients treated surgically due to peripheral nerve injuries in our specialized nerve center for the presence of iatrogenic nerve lesions. METHODS: We evaluated a total of 5026 patients with peripheral nerve injuries treated over a time period of 8 years in our facility for the prevalence of iatrogenic nerve injuries, their clinical presentations, time to treatment, mechanisms and intraoperative findings on nerve continuity. RESULTS: A total of 360 (6.1%) patients had an iatrogenic cause resulting in 380 injured nerves. 76.6% of these lesions affected the main branch of the injured nerve, which were mainly the radial (30.5%), peroneal (13.7%) and median nerve (10.3%). After a mean delay of 237 ± 344 days, patients presented 23.2% with a motor and 27.9% with a mixed sensory and motor deficit. 72.6% of lesions were in-continuity lesions. Main interventions at risk are displayed for every nerve, frequently concerning osteosyntheses but also patient positioning and anesthesiologic interventions. DISCUSSION: Awareness of major surgical complications such as iatrogenic nerve injuries is important for surgeons. An often-seen trivialization or "watch and wait" strategy results in a huge delay for starting an adequate therapy. The high number of in-continuity lesions mainly in close proximity to osteosyntheses makes diagnosis and treatment planning a delicate challenge, especially due to the varying clinical presentations we found. Diagnostics and therapy should therefore be performed as early as possible in specialized centers capable of performing nerve repair as well as salvage therapies.

Improving outcomes in traumatic peripheral nerve injuries to the upper extremity.

Peripheral nerve lesions of the upper extremity are common and are associated with devastating limitations for the patient. Rapid and accurate diagnosis of the lesion by electroneurography, neurosonography, or even MR neurography is important for treatment planning. There are different therapeutic approaches, which may show individual differences depending on the injured nerve. If a primary nerve repair is not possible, several strategies exist to bridge the gap. These may include autologous nerve grafts, bioartificial nerve conduits, or acellular nerve allografts. Tendon and nerve transfers are also of major importance in the treatment of nerve lesions in particular with long regeneration distances. As a secondary reconstruction, in addition to tendon transfers, there is also the option for free functional muscle transfer. In amputations, the prevention of neuroma is of great importance, for which different strategies exist, such as target muscle reinnervation, regenerative peripheral nerve interface, or neurotized flaps. In this article, we give an overview of the latest methods for the therapy of peripheral nerve lesions.

The prognostic role of extended preoperative hypercoagulability work-up in high-risk microsurgical free flaps: a single-center retrospective case series of patients with heterozygotic factor V Leiden thrombophilia.

INTRODUCTION: Hypercoagulability is associated with an increased risk of microvascular complications and free flap failures. The authors present their experience and approach to diagnosing and treating patients with heterozygotic factor V Leiden (hFVL) thrombophilia undergoing free flap reconstruction. METHODS: Between November 2009 and June 2018, 23 free flap surgeries were performed in 15 hypercoagulable patients with hFVL. According to the timing of perioperative hypercoagulability work-up, they were grouped into flaps with established diagnoses prior to surgery (Group A) versus flaps with unknown diagnoses prior to surgery (Group B). Baseline characteristics and perioperative complications were compared between both groups, including revision surgeries due to microvascular thromboses, acute bleedings, hematomas, flap necroses, and reconstructive failures. RESULTS: HFVL mutations had been confirmed preoperatively in 14 free flap surgeries (61%, Group A), whereas in 9 free flap surgeries (39%, Group B), mutations were only diagnosed postoperatively after the occurrence of microvascular thromboses had warranted extended hypercoagulability work-up. The overall rate of intraoperative flap thromboses was 9% (n = 2), whereas the overall rate of postoperative flap thromboses was 43% (n = 10). The corresponding salvage rates were 100% (n = 2/2) for intraoperative and 40% (n = 4/10) for postoperative pedicle thromboses. A total of five free flaps were lost (22%). Upon comparison, flaps with an unconfirmed diagnosis prior to surgery were at ten times higher risk for developing total necroses (flaps lost in Group B = 4/9 versus Group A = 1/14; OR: 10.4; 95% CI 1.0, 134.7; p = 0.03). CONCLUSION: Meticulous preoperative work-up of patients with any history of hypercoagulability can help reduce free flap loss rates, thus improving surgical outcomes and increasing patient safety.

Evaluation of MR-neurography in diagnosis and treatment in peripheral nerve surgery of the upper extremity: A matched cohort study.

INTRODUCTION: "Watch and wait"-strategies from 3 to 6 months for peripheral nerve injuries are standard of care in specialized centers. However, this contradiction between delayed decision-making and the demand for fast reinnervation, especially of the motoric endplate, has not yet been overcome. Therefore, this study aimed to investigate the time-sparing effects by accelerated decision-making due to the complementary MR-neurography application combined with established diagnostics like electroneurography and neurosonography from the first admission to the determination of the treatment plan. PATIENTS AND METHODS: A retrospective matched-pair chart review analysis with Supplementary MR-neurography in the period between 2014 and 2017 was designed. Matching was performed by the parameters of nerve type, localization of the nerve injury, patient age, and treatment of the injury. Twenty-nine patients were included and matched in the study. MR-neurography imaging was performed by a 3T magnetic resonance imaging with a sampling perfection with application optimized contrasts using different flip angle evolution short tau inversion recovery sequence for the brachial plexus and gradient echo accurate fast imaging with steady-state free precession sequence for the upper extremity. Time to decision-making was investigated for or against a surgical intervention for patients with or without a Supplementary MR-neurography. RESULTS: In general, MR-neurography accelerated decision-making for 28 days, with results of 37.5 + 5.4 days with Supplementary MR-neurography and 65.3 + 9.7 days without Supplementary MR-neurography (p = .05). Within the first 90 days following trauma, patients with MR-neurography (38.2 ± 7.7 days) benefit under a significant faster decision-making (p = .05) than patients without MR-neurography (79.0 + 14.2 days). After 90 days, no evidence of accelerated decision-making was found with the addition of MR-neurography (p = .6). In 10 of the 29 patients, despite additional electroneurography and neurosonography, no decision could be made and the MR-neurography has been used primarily as a diagnostic tool. CONCLUSION: MR-neurography has significant time-sparing effects on the decision-making for approximately 4 weeks within the first 90 days after the trauma. This may help overcome the paradigm of "watch and wait"-strategies during the first 3-6 months after the peripheral nerve injury.

Development of a mathematical formula and online tool to calculate the potential maximum flap width to allow for primary anterolateral thigh donor-site closure in Caucasians.

BACKGROUND: Primary anterolateral thigh (ALT) flap donor-site closure is crucial to achieve patient satisfaction, avoid burdensome secondary surgeries, and avert poor outcomes. Only vague maximum flap width recommendations have been suggested, which fall short of acknowledging individual patient habitus and thigh morphology. Therefore, we aimed at identifying a user-friendly preoperative calculation of maximum flap width for primary closure. METHODS: A total of 429 ALT free flaps performed between 2009 and 2020 were analyzed. A total of 350 donor-sites were closed primarily (82%) and 79 (18%) were split-thickness skin-grafted (STSG). Patient demographics including sex, age, and BMI, operative details, and flap characteristics were compared to assess their impact on the outcome variable. Receiver operating characteristic (ROC) curves were plotted for all significant predictors discriminating between closure and STSG. Areas under the curve (AUCs) were calculated for each parameter combination and optimal cutoffs were determined using Youden's Index. RESULTS: Sex, age, BMI, and flap width alone were poor discriminators. Dividing flap width by BMI and logarithmized BMI yielded AUCs of 0.91 and 0.94, respectively. Including patient sex yielded the best fitting regression model (χ2  = 251.939, p < .0001) increasing the AUC to 0.96 (95% CI: 0.93-0.98, p < .0001). The optimal cutoff value discriminated between primary closure and STSG with 90% sensitivity and 89% specificity. An online calculator of patient-individual maximum ALT width was then programmed. CONCLUSIONS: Sex and BMI are reliable predictors of successful primary ALT donor-site closure in Caucasians. We devised a novel formula for calculating patient-individual maximum ALT widths preoperatively, predicting failure of primary closure with 90% sensitivity in our cohort, available at: https://kitteltaschenbuch.com/altwidth/calculate.htm.

Single incision thenar muscle reconstruction using the free functional pronator quadratus flap.

BACKGROUND: Injuries to the thenar muscle mass or the thenar branch of the median nerve and resulting loss of thumb opposition lead to a massive impairment of hand function. For decades, reconstructive approaches were based on tendon transfers. To broaden the reconstructive repertoire, we present the free functional pronator quadratus flap as a viable alternative for functional reconstruction and provide a specification for its indication. We demonstrate our surgical technique to a single incision reconstruction using the free functional pronator quadratus flap. Based on a series of three patients, which were analyzed for hand function using Kapandji's score and the angle of Bourrel, grip strength and nerve conduction velocity in a two year follow up, we present an indication algorithm. RESULTS: After successful reinnervation of all flaps, we found an improvement of Kapandji's score from 4.3 ± 0.94 preoperatively, to 8.7 ± 0.47 after two years. Accordingly, the angle of Bourrel decreased from 75.75 ± 3.45 degrees to 36.96 ± 3.68 degree. Grip strength also improved from 14 ± 2.2 kg to 26.2 ± 1.2 kg. No impairment of wrist pronation was observed. CONCLUSION: We found excellent functional recovery of thumb opposition and strength, showing similar or even superior results compared to results from tendon transfers. With the benefit of a single incision surgery and therefore minimal donor site morbidity, this free functional muscle transfer is a viable alternative to classic tendon transfers.

A Structured, Microsurgical Training Curriculum Improves the Outcome in Lower Extremity Reconstruction Free Flap Residency Training: The Ludwigshafen Concept.

BACKGROUND: Risk stratification, economic pressure, and a flat learning curve make the realization and development of proper microsurgical skills and competences a challenging task in the daily clinical practice. In previous studies, we were able to show that microsurgical procedures, e.g., free flaps and replantations, are safe training procedures and teachable in daily clinical practice in view of certain issues of risk stratification. The present study aims to evaluate further improvements in terms of safety and complication rates for free flaps as a training procedure after introduction and continuous implementation of a structured in-house training curriculum for microsurgical skills and competences and a 24-hour free accessible microsurgical training facility for the plastic surgery resident. METHODS: This retrospective comparative cohort study was conducted to review whether microsurgical skills for free flaps to the lower extremity can further be improved after implementation of the curriculum and a 24-hour accessible training facility. Therefore, we compared cohort A before (2009-2012) and B after (2014-2017) implementation. Patient demographics, procedural characteristics, and outcome parameters for free tissue transfer of the lower extremity were evaluated. RESULTS: The comparison of both cohorts showed a significantly reduced postoperative complication rate for cohort B (p <0.05). Furthermore, operation time was shorter, and the hospital stay could be significantly decreased (p <0.01). Workhorse flaps for plastic surgical training were the anterior lateral thigh (ALT) flap or the musculus latissimus dorsi (LD) flap. However, even more complex procedures with arteriovenous loops could be safely performed by plastic surgery residents under the supervision of the senior surgeon in exceptional cases. CONCLUSION: The implementation of a regularly held, microsurgical in-house training curriculum with 24-hour accessible training facility improves procedural and outcome parameters for free flaps to the lower extremity for surgical residents and is an elementary part of skills and competency training. However, risk stratification, repeated surgical exposure, expertise, and institutional infrastructures are essential and must be taken into consideration.

Neuralgic amyotrophy: a paradigm shift in diagnosis and treatment.

Neuralgic amyotrophy (NA), also known as Parsonage-Turner syndrome, is characterised by sudden pain attacks, followed by patchy muscle paresis in the upper extremity. Recent reports have shown that incidence is much higher than previously assumed and that the majority of patients never achieve full recovery. Traditionally, the diagnosis was mainly based on clinical observations and treatment options were confined to application of corticosteroids and symptomatic management, without proven positive effects on long-term outcomes. These views, however, have been challenged in the last years. Improved imaging methods in MRI and high-resolution ultrasound have led to the identification of structural peripheral nerve pathologies in NA, most notably hourglass-like constrictions. These pathognomonic findings have paved the way for more accurate diagnosis through high-resolution imaging. Furthermore, surgery has shown to improve clinical outcomes in such cases, indicating the viability of peripheral nerve surgery as a valuable treatment option in NA. In this review, we present an update on the current knowledge on this disease, including pathophysiology and clinical presentation, moving on to diagnostic and treatment paradigms with a focus on recent radiological findings and surgical reports. Finally, we present a surgical treatment algorithm to support clinical decision making, with the aim to encourage translation into day-to-day practice.

Bionic hand as artificial organ: Current status and future perspectives.

Even though the hand comprises only 1% of our body weight, about 30% of our central nervous systems (CNS) capacity is related to its control. The loss of a hand thus presents not only the loss of the most important tool allowing us to interact with our environment, but also leaves a dramatic sensory-motor deficit that challenges our CNS. Reconstruction of hand function is therefore not only an essential part of restoring body integrity and functional wholeness but also closes the loop of our neural circuits diminishing phantom sensation and neural pain. If biology fails to restore meaningful function, today we can resort to complex mechatronic replacement that have functional capabilities that in some respects even outperform biological alternatives, such as hand transplantation. As with replantation and transplantations, the challenge of bionic replacement is connecting the target with the CNS to achieve natural and intuitive control. In recent years, we have developed a number of strategies to improve neural interfacing, signal extraction, interpretation and stable mechanical attachment that are important parts of our current research. This work gives an overview of recent advances in bionic reconstruction, surgical refinements over technological interfacing, skeletal fixation, and modern rehabilitation tools that allow quick integration of prosthetic replacement.

Automated muscle fiber type population analysis with ImageJ of whole rat muscles using rapid myosin heavy chain immunohistochemistry.

INTRODUCTION: Skeletal muscle consists of different fiber types which adapt to exercise, aging, disease, or trauma. Here we present a protocol for fast staining, automatic acquisition, and quantification of fiber populations with ImageJ. METHODS: Biceps and lumbrical muscles were harvested from Sprague-Dawley rats. Quadruple immunohistochemical staining was performed on single sections using antibodies against myosin heavy chains and secondary fluorescent antibodies. Slides were scanned automatically with a slide scanner. Manual and automatic analyses were performed and compared statistically. RESULTS: The protocol provided rapid and reliable staining for automated image acquisition. Analyses between manual and automatic data indicated Pearson correlation coefficients for biceps of 0.645-0.841 and 0.564-0.673 for lumbrical muscles. Relative fiber populations were accurate to a degree of ± 4%. CONCLUSIONS: This protocol provides a reliable tool for quantification of muscle fiber populations. Using freely available software, it decreases the required time to analyze whole muscle sections. Muscle Nerve 54: 292-299, 2016.

[Nerve Transfers in Peripheral Nerve Lesions]. / Nerventransfers bei peripheren Nervenläsionen.

BACKGROUND: Lesions of peripheral nerves of the upper extremities often lead to persistent, serious limitations in motor function and sensory perception. Affected patients suffer from both private and professional restrictions associated with long-term physical, psychological and socioeconomic consequences. INDICATION: An early indication for a nerve transfer shortens the reinnervation distance and improves the growing of motor and sensory axons into the target organ to facilitate early mobility and sensitivity. When planning the timepoint of the surgical procedure, the distance to be covered by reinnervation as well as the morbidities of donor nerves must be considered individually. RESULTS: Nerve transfers can achieve earlier and safer reinnervation to improve motor and sensory functions after nerve injuries in the upper extremity.

Ultrasound-An Easy Available and Useful Point-of-Care Adjunct for Clinical Decision-Making in Hand Infections: Review of the Literature and a Case Series.

ABSTRACT: Initial findings of hand infections warrant a thorough treatment strategy depending on the progress of the infection. The decision for surgical treatment can be unclear. Searching to improve the quality of diagnostics, we reviewed the literature regarding the use of point-of-care ultrasound (PCUS) in hand infections and analyzed patients undergoing decision-making with PCUS. We searched PubMed, Scopus, Cochrane Register, and Google Scholar for the use of PCUS in therapy planning in infections of the hand. In addition, we screened our patients from July 1, 2020, to November 30, 2020, to validate the potential benefit of ultrasound examination in suspected hand infections. We evaluated initial clinical examinations versus blinded sonographic assessments in the context of correct decision to proceed with surgery or conservative treatment. Two thousand forty-eight studies within the topic were identified, but only 9 studies were found eligible to be included with a total of 88 patients. The studies illustrate that ultrasound can be performed on all patients, including children and pregnant women, and can be performed in a timely manner. In our retrospective analysis of 20 patients with suspected hand infection, the clinical and ultrasound assessment led to surgery in 13 cases. Of those 13 patients, 7 revealed intraoperative pus. By retrospective assessment of solely the ultrasound images, surgery would have been indicated in 9 cases, including all 7 cases with intraoperative pus. Clinical examination and ultrasound can help in detecting infections of the hand. Ultrasound examination, however, seems to yield a lower false-positive rate than clinical examination. Ultrasound could be a valuable addition to clinical examination.

[Bionic Surgery Meets Bionic Reconstruction - First In-human use of Robotic Microsurgery in Targeted Muscle Reinnervation]. / Bionische Chirurgie trifft Bionische Rekonstruktion ­ erstes in-human Projekt von robotischer Mikrochirurgie zur Targeted Muscle Reinnervation.

Robotic microsurgery is an emerging field in reconstructive surgery, which provides benefits such as improved precision, optimal ergonomics, and reduced tremors. However, only a few robotic platforms are available for performing microsurgical procedures, and successful nerve coaptation is still a challenge. Targeted muscle reinnervation (TMR) is an innovative reconstructive procedure that rewires multiple nerves to remnant stump muscles, thereby reducing neuroma and phantom limb pain and improving the control of bionic prostheses. The precision of surgical techniques is critical in reducing axonal sprouting around the coaptation site to minimise the potential for neuroma formation. This study reports the first use of a microsurgical robotic platform for multiple nerve transfers in a patient undergoing TMR for bionic extremity reconstruction. The Symani robotic platform, combined with external microscope magnification, was successfully used, and precise handling of nerve tissue and coaptation was easily feasible even in anatomically challenging environments. While the precision and stability offered by robotic assistance may be especially useful for nerve surgery, the high economic costs of robotic microsurgery remain a major challenge for current healthcare systems. In conclusion, this study demonstrated the feasibility of using a robotic microsurgical platform for nerve surgery and transfers, where precise handling of tissue is crucial and limited space is available. Future studies will explore the full potential of robotic microsurgery in the future.

Revealing digital nerve lesions-A comprehensive analysis of 2084 cases of a specialized center.

BACKGROUND: Finger nerve injuries have a significant impact on hand function and can result in reduced sensation, pain and impaired coordination. The socioeconomic implications of these injuries include decreased workplace productivity, reduced earning potential, and financial burdens associated with long-term medical treatment and rehabilitation. However, there is a lack of comprehensive literature regarding the incidence, mechanisms, and associated injuries of finger nerve lesions. METHODS: A retrospective analysis was conducted on patients treated at our institution from January 2012 to July 2020. Cases of peripheral finger nerve lesions were identified using the digital hospital information system and ICD-10 Classification. Exclusion criteria included injuries to the median nerve at the carpal tunnel level or superficial branch of the radial nerve. Data were collected using a pseudonymized approach, and statistical analyses were performed using SPSS Statistics (Version 27). RESULTS: A total of 2089 finger nerve lesions were analyzed, with a majority of cases occurring in men. Most injuries97.4 % were caused by trauma, predominantly cut/tear injuries. Isolated finger nerve injuries were more common than multiple nerve injuries, with the index finger being the most frequently affected. Concomitant tendon and vascular injuries were observed in a significant proportion51.7 % of cases. Surgical management included direct nerve coaptation, interposition grafting and neurolysis. DISCUSSION: Finger nerve injuries are the most prevalent type of nerve injury, often resulting from small lacerations. These injuries have substantial societal costs and can lead to prolonged sick leave. Understanding the epidemiology and etiology of finger nerve injuries is crucial for implementing effective preventive measures. Accompanying tendon injuries and the anatomical location of the nerve lesions can impact sensory recovery and treatment outcomes. Proper management of peripheral finger nerve lesions is essential for optimizing functional outcomes and minimizing the impact on daily activities. Treatment options should be tailored to the severity and underlying cause of the nerve injury.

Inferior long-term Results of a Prospective Randomized Controlled Trial initially demonstrating enhanced Sensory Nerve Recovery using a Chitosan Nerve Tube.

INTRODUCTION: Traumatic peripheral nerve injuries can result in significant functional impairments and long-term sequelae. This study evaluated the long-term outcomes of a chitosan tube implantation protecting the epineural coaptation after peripheral nerve injuries using two different tube versions (V 1.0 and V 2.0 with different wall thickness and resorption characteristics) compared to a control group. The study focused on pain levels, sensory function, and overall functional outcomes. METHODS: Patients who received tube implantation around direct coaptation sites of digital nerves were prospectively randomized and compared to control patients without additional tube protection. Pain levels, sensory function, grip force, and functional scores were assessed at different time points, ranging from three months to five years after the procedure. Furthermore, biodegradation of the tubes was measured via high-resolution MR-neurography (MRN) and categorized. RESULTS: Long-term evaluation revealed that patients with V 1.0 had higher pain levels compared to the control group after five years. They also reported more symptoms of numbness and hypersensitivity. V 2.0 patients exhibited higher pain levels at three months, which did not persist at six months. However, they showed compromised sensory function, with higher values of two-point discrimination compared to V 1.0 and the control group. No differences were found in grip force or functional scores between the groups. MRI displayed remnants of implants even in long-term follow-up. DISCUSSION: The findings suggest potential limitations due to pain increase and impaired sensory function associated with tube implantation in the long term. However, in the short term, the material seemed to have a protective effect (as published previously). The resorption process was not completed at the end of the observation period of five years. This might explain the prolonged scarring and inferior long-term results. Future research should focus on improving tube materials and design to minimize adverse effects and enhance functional outcomes in patients with peripheral nerve injuries.

The Surgical Restoration of Arm and Hand Function in Tetraplegic Patients.

BACKGROUND: There are approximately 140 000 people in Germany with spinal cord injury, with approximately 2400 new patients each year. Cervical spinal cord injuries cause, to varying degrees, weakness and impairment of everyday activities of the limbs (tetraparesis, tetraplegia). METHODS: This review is based on relevant publications retrieved by a selective search of the literature. RESULTS: From among 330 initially screened publications, 40 were included and analyzed. Muscle and tendon transfers, tenodeses, and joint stabilizations yielded reliable functional improvement of the upper limb. Tendon transfers improved the strength of elbow extension from M0 to an average of M3.3 (BMRC) and grip strength to approximately 2 kg. In the long term, 17-20% of strength is lost after active tendon transfers and slightly more after passive ones. Nerve transfers improved strength to M3 or M4 in over 80% of cases, with the best results overall in patients under 25 years of age who underwent early surgery (within 6 months of the accident). Combined procedures in a single operation have been found to be advantageous compared to the traditional multistep approach. Nerve transfers from intact fascicles at segmental levels above that of the spinal cord lesion have been found to be a valuable addition to the established varieties of muscle and tendon transfer. The reported long-term patient satisfaction is generally high. CONCLUSION: Modern techniques of hand surgery can help suitably selected tetraparetic and tetraplegic patients regain the use of their upper limbs. Competent interdisciplinary counseling about these surgical options should be offered as early as possible to all affected persons as an integral part of their treatment plan.

Benefit of Adjuvant Mesenchymal Stem Cell Transplantation to Critical-Sized Peripheral Nerve Defect Repair: A Systematic Review and Meta-Analysis of Preclinical Studies.

Critically sized nerve defects cause devastating life-long disabilities and require interposition for reconstruction. Additional local application of mesenchymal stem cells (MSCs) is considered promising to enhance peripheral nerve regeneration. To better understand the role of MSCs in peripheral nerve reconstruction, we performed a systematic review and meta-analysis of the effects of MSCs on critically sized segment nerve defects in preclinical studies. 5146 articles were screened following PRISMA guidelines using PubMed and Web of Science. A total of 27 preclinical studies (n = 722 rats) were included in the meta-analysis. The mean difference or the standardized mean difference with 95% confidence intervals for motor function, conduction velocity, and histomorphological parameters of nerve regeneration, as well as the degree of muscle atrophy, was compared in rats with critically sized defects and autologous nerve reconstruction treated with or without MSCs. The co-transplantation of MSCs increased the sciatic functional index (3.93, 95% CI 2.62 to 5.24, p < 0.00001) and nerve conduction velocity recovery (1.49, 95% CI 1.13 to 1.84, p = 0.009), decreased the atrophy of targeted muscles (gastrocnemius: 0.63, 95% CI 0.29 to 0.97 p = 0.004; triceps surae: 0.08, 95% CI 0.06 to 0.10 p = 0.71), and promoted the regeneration of injured axons (axon number: 1.10, 95% CI 0.78 to 1.42, p < 0.00001; myelin sheath thickness: 0.15, 95% CI 0.12 to 0.17, p = 0.28). Reconstruction of critically sized peripheral nerve defects is often hindered by impaired postoperative regeneration, especially in defects that require an autologous nerve graft. This meta-analysis indicates that additional application of MSC can enhance postoperative peripheral nerve regeneration in rats. Based on the promising results in vivo experiments, further studies are needed to demonstrate potential clinical benefits.

Hopeless Neuroma-The Neurotized Free Flap Tissue Augmentation as Salvage Therapy-A Concept and Clinical Demonstration.

Therapy-resistant neuroma pain is a devastating condition for patients and surgeons. Although various methods are described to surgically deal with neuromas, some discontinuity and stump neuroma therapies have anatomical limitations. It is widely known that a neurotizable target for axon ingrowth is beneficial for dealing with neuromas. The nerve needs "something to do". Furthermore, sufficient soft tissue coverage plays a major role in sufficient neuroma therapy. We aimed, therefore, to demonstrate our approach for therapy of resistant neuromas with insufficient tissue coverage using free flaps, which are sensory neurotized via anatomical constant branches. The central idea is to provide a new target, a new "to do" for the painful mislead axons, as well as an augmentation of deficient soft tissues. As indication is key, we furthermore demonstrate clinical cases and common neurotizable workhorse flaps.