Influence of immobilization and sensory re-education on the sensory recovery after reconstruction of digital nerves with direct suture or muscle-in-vein conduits.

The influence of duration of immobilization and postoperative sensory re-education on the final outcome after reconstruction of digital nerves with direct suture or muscle-in-vein conduits was investigated. The final sensory outcome of 35 patients with 41 digital nerve injuries, who either underwent a direct suture (DS) or a nerve reconstruction with muscle-in-vein conduits (MVC), was assessed the earliest 12 months postoperatively using static and moving two-point discrimination as well as Semmes-Weinstein monofilaments. There was no significant difference in sensory recovery in cases with an immobilization of 3-7 days versus 10 days in the DS or MVC group. Moreover, no statistically significant difference in sensory recovery was found in cases receiving postoperative sensory re-education versus those not receiving in the DS or MVC group. An early mobilization does not seem to have a negative impact on the final outcome after digital nerve reconstruction. The effect of sensory re-education after digital nerve reconstruction should be reconsidered.

Analysis of the microcirculation after soft tissue reconstruction of the outer ear with burns in patients with severe burn injuries.

Reconstruction of soft tissue defects of the ear with burns remains one of the most difficult tasks for the reconstructive surgeon. Although numerous reconstructive options are available, the results are often unpredictable and worse than expected. Besides full and split skin grafting, local random pattern flaps and pedicled flaps are frequently utilized to cover soft tissue defects of the outer auricle. Because of the difficulty and unpredictable nature of outer ear reconstruction after burn injury, a case-control study was conducted to determine the best reconstructive approach. The microcirculatory properties of different types of soft tissue reconstruction of the outer ear with burns in six severely burned Caucasian patients (three men and three women; mean age, 46 years (range, 22-70)) were compared to those in the healthy tissue of the outer ear using the O2C device (Oxygen to See; LEA Medizintechnik, Gießen, Germany). The results of this study revealed that the investigated microcirculation parameters such as the median values of blood flow (control group: 126 AU), relative amount of hemoglobin (control group: 59.5 AU), and tissue oxygen saturation (control group: 73%) are most similar to those of normal ear tissue when pedicled flaps based on the superficial temporal artery were used. These findings suggest that this type of reconstruction is superior for soft tissue reconstruction of the outer ear with burns in contrast to random pattern flaps and full skin grafts regarding the microcirculatory aspects. These findings may improve the knowledge on soft tissue viability and facilitate the exceptional and delicate process of planning the reconstruction of the auricle with burns.

Bilateral comparison of the vascular pattern of the superficial temporal artery based on digital subtraction angiography.

PURPOSE: This study was performed to investigate any bilateral differences in the vascular pattern and microsurgical relevant parameters of the superficial temporal artery (STA) in vivo. METHODS: Digital subtraction angiographies of the STA of 38 individuals were retrospectively analyzed. A bilateral comparison of the branching pattern as well as of surgically relevant diameters and lengths of the main branches of the STA was performed. Moreover, gender-specific differences were assessed. RESULTS: Only 10 cases (26%) demonstrated an identical type and subtype of the STA pattern bilaterally. The diameters of the STA at its origin and bifurcation level as well as of its parietal branch were statistically significant wider on the right than on the left side (p(o) = 0.0009, p(b) = 0.006, p(p) = 0.030). Moreover, the diameters of the STA at its origin level on the right side, at its bifurcation level on both sides and of the frontal branch on both sides were statistically significant wider in males than females. No statistically significant differences of the lengths of the STA and its main branches between the right and the left side were identified. CONCLUSION: The occurrence of the vascular pattern of the STA in vivo is random for each side of the same person and cannot be predicted by the vascular pattern of the opposite side. The calibers of the main branches of the STA are gender specific and commonly larger on the right than on the left side.

Comparison of short- with long-term regeneration results after digital nerve reconstruction with muscle-in-vein conduits.

Muscle-in-vein conduits are used alternatively to nerve grafts for bridging nerve defects. The purpose of this study was to examine short- and long-term regeneration results after digital nerve reconstruction with muscle-in-vein conduits. Static and moving two-point discriminations and Semmes-Weinstein Monofilaments were used to evaluate sensory recovery 6-12 months and 14-35 months after repair of digital nerves with muscle-in-vein in 7 cases. Both follow-ups were performed after clinical signs of progressing regeneration disappeared. In 4 of 7 cases, a further recovery of both two-point discriminations and in another case of only the static two-point discrimination of 1-3 mm could be found between the short-term and long-term follow-up examination. Moreover, a late recovery of both two-point discriminations was demonstrated in another case. Four of 7 cases showed a sensory improvement by one Semmes-Weinstein Monofilaments. This pilot study suggests that sensory recovery still takes place even when clinical signs of progressing regeneration disappear.

Treatment Algorithm and Clinical Outcome of Venous Malformations of the Limbs.

BACKGROUND: Venous malformations of the limbs are congenital low-flow vascular anomalies. A treatment is reasonable if they are symptomatic or if a progressive lesion may affect functional structures. OBJECTIVE: The purpose of this work is the presentation of clinical results after treatment of venous malformations of the limbs according to the standard algorithm used at the University Hospital of Tuebingen, Germany. PATIENTS AND METHODS: Between January 2008 and June 2015, patients with venous malformations of the limbs were subjected to either percutaneous sclerotherapy or surgical excision according to this treatment algorithm. Remaining symptoms such as pain level and disturbing appearance before and after treatment as well as overall satisfaction was assessed the earliest 3 months after last treatment. RESULTS: Thirty-nine patients with venous malformations of the limbs were subjected to either 1 or more percutaneous sclerotherapies (n = 19) or surgical excision (n = 21). There were no serious complications that needed surgical revision. There was a statistically significant reduction in the pain level and disturbing appearance after both sclerotherapy and surgical excision (p < .05) in 30 cases in total. The overall treatment satisfaction was rated 7.9/10 and 8.8/10 after sclerotherapy and surgical excision, respectively. CONCLUSION: A low complication rate with a high patient satisfaction could be achieved after this treatment algorithm for venous malformations of the limbs.

Comparison of clinical and radiologic treatment outcomes of Kienböck's disease.

PURPOSE: The clinical outcomes of scaphotrapeziotrapezoid (STT) arthrodesis were compared to radial shortening osteotomy (RSO) to determine if any of the treatment methods was superior. The impact of RSO and vascularized bone grafts (VBG) on disease progression were measured based on X-rays to evaluate if a difference in Kienböck's disease (KD) progression exists. METHODS: Out of 98 consecutive patients treated between 1991 and 2013, 46 had STT arthrodesis, 21 had RSO, 7 had VBG, and 3 had VBG and RSO. Patients treated with STT arthrodesis were compared to RSO regarding post-operative range of motion (ROM), wrist pain on the Numeric Rating Scale (NRS), grip strength, duration of incapacity for work, the Disabilities of the Arm, Shoulder, and Hand (DASH), and the Modified Mayo Wrist scores (MMWS). Radiographic assessment (Nattrass index, radioscaphoid angle, and Ståhl index) was performed to determine disease progression following RSO or VBG. Baseline patient characteristics were comparable in all treatment groups. RESULTS: There were no significant differences in post-operative ROM, wrist pain, grip strength, duration of incapacity, DASH score, or MMWS score following STT arthrodesis (n = 27) or RSO (n = 14). The Ståhl index, the Nattrass index, and the radioscaphoid angle suggested disease progression following RSO (n = 14) and/or VBG (n = 6) although the changes were not significant. CONCLUSIONS: The study failed to demonstrate clinically relevant differences between STT arthrodesis compared to RSO. No evidence was found that decompression or revascularization, or the combination of the two, can reverse or halt the course of the disease. LEVEL OF EVIDENCE: Therapy, level III, retrospective comparative study with prospectively collected data.

In vivo analysis of the vascular pattern of the superficial temporal artery based on digital subtraction angiography.

BACKGROUND: Existing anatomic descriptions of the superficial temporal artery (STA) are mainly based on cadaver studies and do not accurately reflect the in vivo situation. In this study, the anatomical course and branching pattern of the STA were analyzed with digital subtraction angiographies (DSAs). METHODS: DSAs of 93 Caucasian individuals between 16- and 79-years old were retrospectively analyzed regarding the course and branching pattern of the STA as well as surgically relevant inner diameters and lengths of its main branches. RESULTS: In total, 11 variations in the branching pattern of the terminal STA were found. About 89% of the examined individuals demonstrated the classic variation in which the main trunk of the STA bifurcates into a single frontal and parietal branch. In 60% of cases with an existing bifurcation, the division of the main trunk of the STA was located above the zygoma. The mean inner diameters of the STA main trunk, the frontal branch and the parietal branch were 2.4 ± 0.6 mm, 1.3 ± 0.6 mm and 1.2 ± 0.4 mm, respectively. The surgically relevant "working lengths" of the frontal and parietal branches above the upper margin of the zygoma up to an inner diameter of 1 mm were 106.4 ± 62.1mm and 99.7 ± 40.9 mm, respectively. CONCLUSIONS: The common variations of the branching pattern of the STA are described in this study. Furthermore, surgically relevant inner diameters and lengths of the main branches of the STA are determined. These findings should improve our understanding of the suitability and usefulness of the STA for various surgical procedures.

A novel hand-shaped suprathel simplifies the treatment of partial-thickness burns.

OBJECTIVE: The standard therapy to treat superficial partial-thickness burns of the hand involves the application of skin substitutes such as Suprathel (PolyMedics Innovations GmbH, Denkendorf, Germany), which reduce pain significantly, thus allowing a fast mobilization and leading to a quicker restoration of function. The aim of this study was to simplify the application of Suprathel by using new precut hand-shaped bandages. METHODS: Suprathel sheets have been produced in precut hand shapes that can be applied on the palm or on the dorsum of the hand. During a 6-month study period, 24 patients were treated with Suprathel after a burn injury of the hand. Half the patients received standard Suprathel sheets, and half received the novel hand-shaped Suprathel. Application time and material waste were documented closely. RESULTS: By using the Hand-Suprathel, application time was significantly reduced up to 80% compared with the standard rectangular Suprathel sheets. When the standard Suprathel sheet was reduced to the size and shape of the hand, approximately 40% of the material was discharged. In contrast, almost no material waste occurred by using Hand-Suprathel. CONCLUSION: The use of the new Hand-Suprathel increases efficiency because of its convenient and faster application, as well as by reducing material waste.

Evaluation of sensory recovery after reconstruction of digital nerves of the hand using muscle-in-vein conduits in comparison to nerve suture or nerve autografting.

BACKGROUND: Muscle-in-vein conduits are a good alternative solution to nerve autografts for bridging peripheral nerve defects since enough graft material is available and no loss of sensation at the harvesting area is expected. The purpose of this study was to compare regeneration results after digital nerve reconstruction with muscle-in-vein conduits, nerve autografts, or direct suture. PATIENTS AND METHODS: 46 patients with 53 digital nerve injuries of the hand subjected to direct suture (n = 22) or reconstruction of 1-6 cm long defects with either nerve autografts (n = 14) or muscle-in-vein conduits (n = 17) between 2008 and 2012, were examined using the two-point discrimination and Semmes-Weinstein Monofilaments. RESULTS: The follow-up examinations took place 12 to 58 months after surgery. A median reduction of sensibility of 2 Semmes-Weinstein monofilaments compared with intact digits was observed after direct suture (DS) and of 2.5 and 2 Semmes-Weinstein monofilaments after reconstruction with autologous nerve grafts (ANG) and muscle-in-vein conduits (MVC), respectively. No statistically significant differences between all three groups could be found with a significance level set by a P < 0.006 (PDS-ANG = 0.24, PDS-MVC = 0.03, PANG-MVC = 0.52). After harvesting a nerve graft, reduction of sensibility at the donor site occurred in 10 of 14 cases but only in one case after harvesting a muscle-in-vein conduit. CONCLUSIONS: Muscle-in-vein conduits may be a good alternative solution to autografts for the reconstruction of digital nerves, since no significant differences could be demonstrated between the two methods.

Correlation analysis of histomorphometry and motor neurography in the median nerve rat model.

OBJECTIVE: Standard methods to evaluate the functional regeneration after injury of the rat median nerve are insufficient to identify any further differences of axonal nerve regeneration after restitution of motor recovery is completed. An important complementary method for assessing such differences is a histomorphometric analysis of the distal to lesion nerve fibers. Recently, an electrophysiological method has been proposed as a sensitive method to examine the quality of axonal nerve regeneration. METHODS: A linear regression analysis has been performed to correlate histomorphometric and neurographic data originating from 31 rats subjected to neurotmesis and immediate reconstruction of their right median nerve. RESULTS: A significant linear correlation between the velocity of neuromuscular conduction and the total number of nerve fibers (P = .037) as well as between the amplitude of compound muscle action potential and the total number of nerve fibers (P = .026) has been identified. Interestingly, a significant correlation between the velocity of neuromuscular conduction and the square root of the cross-sectional area of the nerve could be found (P = .008). This corresponds to a linear correlation between the velocity of neuromuscular conduction and the radius of the nerve. CONCLUSION: These results contribute in a better interpretation of morphological predictors of nerve regeneration and verify the previously described electrophysiological assessment in the median nerve rat model as a valid method.

Characteristic features and natural evolution of Kienböck's disease: five years' results of a prospective case series and retrospective case series of 106 patients.

OBJECTIVES: Scientific databases index numerous references related to the treatment of Kienböck's disease; yet little is known about the nature of the disease and its pathognomonic features. This study provides a cross-sectional analysis of the pattern and extent of osteonecrosis in a large cohort and a longitudinal analysis to determine the spontaneous disease progression in single patients who have not had surgical management until fragmentation of the lunate. METHODS: In a prospective case series, the pattern and extent of osteonecrosis were correlated with the duration of symptoms in all patients with Kienböck's disease confirmed using high-resolution 3-T magnetic resonance imaging (MRI) and ultra-thin section computed tomographic (CT) scan since 2009. Furthermore, a retrospective consecutive case series study was conducted to determine the rate of spontaneous evolution in all consecutive patients treated conservatively in our university hospital since 1990. RESULTS: Among the 35 consecutive patients with Kienböck's disease diagnosed in high-resolution 3-T MRI and ultra-thin section CT, 46% (16/35) presented degeneration of lunate cartilage on CT scan in the first 12 months following the onset of symptoms. Median wrist pain duration of patients presenting a fracture of the lunate was 14 months. Thirty-one percent (11/35) of the patients had arthritis of the lunate, yet no fractures at the time of examination. Of 106 consecutive patients with Kienböck's disease and complete records, who did not have surgical intervention until fragmentation of the lunate, three cases were identified with well-documented spontaneous courses from apparently intact lunate morphology until fragmentation within 6 months. CONCLUSIONS: Kienböck's disease progresses substantially faster than previously described and, contrary to current classifications, the articular cartilage of the lunate degenerates in early stages. LEVEL OF EVIDENCE: Diagnostic accuracy, Level IV.

Prospective case-control study on the etiopathology of Kienböck disease.

BACKGROUND: Multiple hypotheses regarding the cause of Kienböck disease have been proposed in seemingly contradictory small case series and cohort studies with inadequate statistical power. A prospective case-control study was conducted to analyze frequently discussed risk and causal factors. METHODS: Eighty-one consecutive patients with Kienböck disease and 198 patients with wrist ganglia were referred to the authors' clinic between 1990 and 2012, and 2003 and 2011, respectively. Patients with wrist ganglia were chosen as a control group because of the similar age distribution compared with the general population and because the common etiopathologic features of wrist ganglia and Kienböck disease can be excluded. Demographic, occupational, and medical information, including age, sex, handedness, ethnicity, education, occupation and employment status, prior treatment, and medical history were collected. Associated conditions and medication were assessed at a follow-up examination. RESULTS: Sixty-five of 81 patients with Kienböck disease and 70 of 198 controls were included in the study. Both groups were comparable with respect to age distribution and handedness. Employment status and job characteristics were similar in both groups. Hand-arm vibration during work or leisure activity over a period of 2 years was present in 23 percent with Kienböck disease and in 24 percent of 70 controls. Cortisone was used in six of 65 cases with Kienböck disease [controls, zero of 70] for an average duration of 46 months. CONCLUSIONS: Trauma, hand-arm vibration, heavy manual labor, and comorbidities were not associated with Kienböck disease. Steroid-associated Kienböck disease in six of 65 cases is consistent with the findings reported for osteonecrosis of other parts of the skeleton. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

The role of antibiotics after surgical treatment of simple hand infections: a prospective pilot study.

BACKGROUND: Manifested hand infections are usually treated by sufficient debridement and drainage followed by splinting and elevation of the corresponding upper extremity. The role of antibiotics in the postoperative prognosis of hand infections is contradictory. METHODS: Three groups of 30 patients each with subcutaneous or subfascial localized hand infections without infiltration of tendons, joints, or bones, have been treated in a different way regarding the use of antibiotics postoperatively. Group 1 was treated with systemic cephalosporins as well as locally inserted Gentamycin bead chains in the wound after debridement. Group 2 was only treated locally with Gentamycin bead chains but no systemic antibiots, while Group 3 did not receive any antibiotics at all. RESULTS: No substantial differences could be observed between the three patient groups regarding the convalescence in terms of duration of splinting and recovery of hand function in relation to hand mobility as assessed by the sum of finger-palm distance and to the disabilities of the arm, shoulder, and hand score. CONCLUSIONS: The use of antibiotics after surgical treatment of simple hand infections seems to be unnecessary.

Application of two different hemostatic procedures during microsurgical median nerve reconstruction in the rat does not hinder axonal regeneration.

BACKGROUND: Hemostatic procedures by means of electrical coagulation or application of topical agents are widely used to avoid postoperative bleeding during microsurgical reconstruction of peripheral nerves. It is speculated, however, that extensive hemostasis could provoke significant nerve damage. OBJECTIVE: To examine the effects of 2 intraoperative hemostatic procedures on peripheral nerve regeneration. METHODS: In 36 adult rats divided into 3 groups, the median nerve was transected and repaired by end-to-end neurorrhaphy. During surgery, bleeding was treated in groups 2 and 3 by application of either the topical hemostatic agent Floseal or routine bipolar coagulation. The degree of nerve regeneration was assessed in terms of motor function recovery using weekly grasping test evaluation for 3 months, muscle mass recovery of flexor digitorum sublimis, and stereological assessment of myelinated axon regeneration. RESULTS: Neither of the 2 applied hemostatic methods induced any negative effects on nerve regeneration as defined by grip strength, muscle mass recovery, and morphology of myelinated nerve fibers. In contrast, Floseal-treated animals showed a faster progression of motor function recovery, and animals subjected to bipolar coagulation revealed a higher muscle mass recovery compared with the control group. CONCLUSION: Controlled application of bipolar coagulation or Floseal does not exert a negative effect on the nerve regeneration outcome in rats. We propose that these methods can be applied safely to patients.

One-stage ear reconstruction after avulsion injury, using the amputated cartilage and a retroauricular transposition flap.

INTRODUCTION: Auricular reattachment or reconstruction after traumatic ear loss remains a challenge for the plastic reconstructive surgeon. Because of the diverse accident mechanisms, no standard algorithms exist and several modalities have been proposed in the literature. METHODS: A case of an innovative ear reconstruction of a partially avulsed ear is presented. The amputated cartilage was reattached after being deepithelized from the anterior skin. A transauricular-retroauricular random pattern flap was then harvested and used for anterior skin coverage. RESULTS: The described technique provided a nice final result without the need of any further operations. CONCLUSION: In general, a microsurgical replantation should be applied when the circumstances allow. In other cases, especially in partial upper-ear amputations with severe skin contusions, the described technique should be considered as a safe, single-step approach with good final results.

Efficacy of various durations of in vitro predegeneration on the cell count and purity of rat Schwann-cell cultures.

The efficacy of Schwann-cell cultivation can be enhanced by in vitro predegeneration of the harvested cells compared to immediate culture. The aim of this study was to improve Schwann-cell culture efficacy by comparing three different durations of predegeneration. The sciatic and median nerves of 6-8-week-old Lewis rats were harvested and subjected to either 2-day, 7-day, or 14-day predegeneration in Dulbecco's Modified Eagle's Medium supplemented with 10% fetal calf serum and 1% Penicillin/Streptomycin. Afterward, tissue was enzymatically dissociated and placed in a modified melanocyte growth medium. The cell count was determined immediately after dissociation while the cell purity was determined one subculture/trypsinization cycle later after cell attachment to the culture plate by means of optical microscopy and immunocytochemistry. Particular attention was then paid to the Schwann-cell-to-fibroblast relation. The cumulative cell count in the culture was 5.8 x 10(5) for 2-day, 1.12 x 10(6) for 7-day, and 1.48 x 10(6) for 14-day predegeneration. The culture purity was approximately equal for 2- and 7-day predegeneration (88% Schwann cells, 12% fibroblasts after 2 days; 85% Schwann cells, 15% fibroblasts after 7 days). After 14 days, however, cell cultures were significantly debased by fibroblast proliferation (57% Schwann cells, 43% fibroblasts). In vitro predegeneration is a particularly suitable procedural method to increase the cultural Schwann-cell yield. The number of cultivated rat Schwann cells is doubled by 7-day in vitro predegeneration in comparison to 2-day predegeneration. After 14-day predegeneration, however, the culture is significantly debased by fibroblasts. Therefore, 7-day in vitro predegeneration is an advisable predegeneration period.

An improved electrophysiological method to study peripheral nerve regeneration in rats.

After restitution of motor function the grasping test alone is insufficient to figure out any further differences of axonal nerve regeneration of the median nerve in rats. To avoid this problem we developed a standardized electrophysiologic method for testing median nerve regeneration. Threshold, latency, compound muscle action potentials (CMAP) and velocity of neuromuscular transduction were recorded in 54 rats 20 weeks post-operatively. Animals of group 1 served as control group, no transection of the median nerve was carried out. Animals of groups 2 and 3 underwent either primary nerve coaptation or autologous nerve grafting after transection of the median nerve. To ensure validity of the method additional correlation between all parameters was investigated. Reliable electrophysiological results were observed in all animals. As expected, group 1 animals showed lowest threshold and latency and highest CMAP levels. Transection of the median nerve and additional nerve repair leads to significant increase of threshold and latency as well as reduction of CMAP. Furthermore, animals of group 3 showed higher levels for threshold and latency and reduced CMAP levels compared with animals of group 2. The grasping test alone could not demonstrate these slight differences 20 weeks post-operatively. Additionally, we observed strong correlations between threshold, latency and CMAP using the Spearman correlation ranking. We describe the usage of motor neurography as a reproducible and valid tool which should be mandatory for detailed analysis of regeneration in the rat median nerve model.

Group testing for pathway analysis improves comparability of different microarray datasets.

MOTIVATION: The wide use of DNA microarrays for the investigation of the cell transcriptome triggered the invention of numerous methods for the processing of microarray data and lead to a growing number of microarray studies that examine the same biological conditions. However, comparisons made on the level of gene lists obtained by different statistical methods or from different datasets hardly converge. We aimed at examining such discrepancies on the level of apparently affected biologically related groups of genes, e.g. metabolic or signalling pathways. This can be achieved by group testing procedures, e.g. over-representation analysis, functional class scoring (FCS), or global tests. RESULTS: Three public prostate cancer datasets obtained with the same microarray platform (HGU95A/HGU95Av2) were analyzed. Each dataset was subjected to normalization by either variance stabilizing normalization (vsn) or mixed model normalization (MMN). Then, statistical analysis of microarrays was applied to the vsn-normalized data and mixed model analysis to the data normalized by MMN. For multiple testing adjustment the false discovery rate was calculated and the threshold was set to 0.05. Gene lists from the same method applied to different datasets showed overlaps between 42 and 52%, while lists from different methods applied to the same dataset had between 63 and 85% of genes in common. A number of six gene lists obtained by the two statistical methods applied to the three datasets was then subjected to group testing by Fisher's exact test. Group testing by GSEA and global test was applied to the three datasets, as well. Fisher's exact test followed by global test showed more consistent results with respect to the concordance between analyses on gene lists obtained by different methods and different datasets than the GSEA. However, all group testing methods identified pathways that had already been described to be involved in the pathogenesis of prostate cancer. Moreover, pathways recurrently identified in these analyses are more likely to be reliable than those from a single analysis on a single dataset.