Measuring quality of care in autologous breast reconstruction: a Delphi consensus.

Measuring and benchmarking quality of care in surgical oncology has been gaining popularity. In autologous breast reconstruction (ABR), a standardized set of indicators to assess quality of care is lacking. In this study, we defined a set of evidence-based quality indicators for autologous breast reconstruction. First, we performed a systematic review to identify factors related to quality of care in ABR. Variables were categorized depending on their function: indicators related to outcome, indicators related to process and case-mix variables. The review was followed by a 3-round Delphi Consensus to determine which indicators and case-mix-variables were considered relevant and feasible for inclusion in an ABR standard set of indicators. 932 unique articles were identified, of which 110 papers were included in the study. Indicators were categorized by function: outcome, process and case-mix variables. In total, 8 process indicators and 41 outcome indicators were extracted. 30 case-mix-variables were included. Following 3 rounds of questioning in the Delphi Consensus, all respondents agreed on type of ABR, oncological outcomes and patient satisfaction for the standard set. Indicators related to complications were consistently ranked highly. Most process indicators were not chosen after 3 rounds of questioning. 11 case-mix-variables were included in the final set. Following the Delphi Consensus, it was possible to identify 33 process and outcome indicators and 11 case-mix-variables for inclusion for a standard set of quality indicators. With the inclusion of both objective and patient-reported outcome measures, this set of indicators provides a multidimensional measurement tool for quality assessment for ABR.

Targeted therapies and checkpoint inhibitors in sarcoma.

Sarcomas are defined as a group of mesenchymal malignancies with over 100 heterogeneous subtypes. As a rare and difficult to diagnose entity, micrometastasis is already present at the time of diagnosis in many cases. Current treatment practice of sarcomas consists mainly of surgery, (neo)adjuvant chemo- and/or radiotherapy. Although the past decade has shown that particular genetic abnormalities can promote the development of sarcomas, such as translocations, gain-of-function mutations, amplifications or tumor suppressor gene losses, these insights have not led to established alternative treatment strategies so far. Novel therapeutic concepts with immunotherapy at its forefront have experienced some remarkable success in different solid tumors while their impact in sarcoma remains limited. In this review, the most common immunotherapy strategies in sarcomas, such as immune checkpoint inhibitors, targeted therapy and cytokine therapy are concisely discussed. The programmed cell death (PD)-1/PD-1L axis and apoptosis-inducing cytokines, such as TNF-related apoptosis-inducing ligand (TRAIL), have not yielded the same success like in other solid tumors. However, in certain sarcoma subtypes, e.g. liposarcoma or undifferentiated pleomorphic sarcoma, encouraging results in some cases when employing immune checkpoint inhibitors in combination with other treatment options were found. Moreover, newer strategies such as the targeted therapy against the ancient cytokine macrophage migration inhibitory factor (MIF) may represent an interesting approach worth investigation in the future.

Diagnostic pitfall: pigmented lesion of the nipple--correlation between dermoscopy, reflectance confocal microscopy and histopathology.

We present an unusual case of a nevus of the nipple changing during pregnancy which caused a diagnostic pitfall. Nevi on the nipple and areola are infrequent, and diagnostic criteria for clinical, dermoscopy or reflectance confocal microscopy examination for nevi in this 'special location' are still missing. We comment on the literature on dermoscopic findings in mammary lesions and their management during pregnancy, as well as the challenging histopathology of nevi along the milk line. Finally, we focus on two main limitations of reflectance confocal microscopy: the misinterpretation of dendritic cells and the limitation of the imaging depth.

Morphology and hemodynamics during vascular regeneration in critically ischemic murine skin studied by intravital microscopy techniques.

BACKGROUND: With the understanding of angiogenesis and arteriogenesis, new theories about the orchestration of these processes have emerged. The aim of this study was to develop an in vivo model that enables visualization of vascular regenerating mechanisms by intravital microscopy techniques in collateral arteriolar flap vascularity. METHODS: A dorsal skin flap (15 × 30 mm) was created in mice and fixed into a skinfold chamber to allow for assessment of morphology and microhemodynamics by intravital fluorescence microscopy (IVFM). Laser scanning confocal microscopy (LSCM) was utilized for three-dimensional reconstruction of the microvascular architecture. RESULTS: Flap tpO(2) was 5.3 ± 0.9 versus 30.5 ± 1.2 mm Hg in controls (p < 0.01). The collateral arterioles in the flap tissue were dilated (29.4 ± 5.3 µm; p < 0.01 vs. controls) and lengthened in a tortuous manner (tortuosity index 1.00 on day 1 vs. 1.35± 0.05 on day 12; p < 0.01). Functional capillary density was increased from 121.00 ± 25 to 170 ± 30 cm/cm(2) (day 12; p < 0.01) as a result of angiogenesis. Morphological evidence of angiogenesis on capillary level and vascular remodeling on arteriolar level could be demonstrated by IVFM and LSCM. CONCLUSIONS: Present intravital microscopy techniques offer unique opportunities to study structural changes and hemodynamic effects of vascular regeneration in this extended axial pattern flap model.

The influence of sentinel lymph node tumour burden on additional lymph node involvement and disease-free survival in cutaneous melanoma--a retrospective analysis of 392 cases.

Twenty per cent of sentinel lymph node (SLN)-positive melanoma patients have positive non-SLN lymph nodes in completion lymph node dissection (CLND). We investigated SLN tumour load, non-sentinel positivity and disease-free survival (DFS) to assess whether certain patients could be spared CLND. Sentinel lymph node biopsy was performed on 392 patients between 1999 and 2005. Median observation period was 38.8 months. Sentinel lymph node tumour load did not predict non-SLN positivity: 30.8% of patients with SLN macrometastases (> or =2 mm) and 16.4% with micrometastases (< or =2 mm) had non-SLN positivity (P=0.09). Tumour recurrences after positive SLNs were more than twice as frequent for SLN macrometastases (51.3%) than for micrometastases (24.6%) (P=0.005). For patients with SLN micrometastases, the DFS analysis was worse (P=0.003) when comparing those with positive non-SLNs (60% recurrences) to those without (17.6% recurrences). This difference did not translate into significant differences in DFS: patients with SLN micrometastasis, either with (P=0.022) or without additional positive non-SLNs (P<0.0001), fared worse than patients with tumour-free SLNs. The 2-mm cutoff for SLN tumour load accurately predicts differences in DFS. Non-SLN positivity in CLND, however, cannot be predicted. Therefore, contrary to other studies, no recommendations concerning discontinuation of CLND based on SLN tumour load can be deduced.

Retrograde fixation of metacarpal fractures with intramedullary cannulated headless compression screws.

We analyzed the results of 20 unstable metacarpal fractures in 15 patients treated with a cannulated compression screw and no immobilization. All fractures healed within 6 weeks. One patient with multiple fractures and a flexion deficit required arthrolysis of two metacarpophalangeal joints. Another patient had an extension lag. There were no other complications. This fast and easy technique results in good outcomes for unstable metacarpal fractures. The advantages are early active motion without immobilization and stable fixation. Surgical removal of the screw is rarely needed. LEVEL OF EVIDENCE: IV (therapeutic).

[Surgical treatment of high-voltage electrical injuries]. / Die chirurgische Behandlung von Hochspannungsverletzungen.

PURPOSE/BACKGROUND: High-voltage burns represent a challenging surgical entity. Compared to conventional burns, these injuries are characterized by an increased morbidity and worse potential for rehabilitation. The aim of the present study was to analyse the management of high-voltage injuries during the early posttraumatic period with special emphasis on the surgical procedures. PATIENTS/MATERIAL AND METHOD: We retrospectively evaluated the medical records of patients with electrical injuries treated from 1995 - 2007. A total of 61 patients (57 men, 4 females, mean age: 34 +/- 13 years) with high-voltage burns was included for analysis. RESULTS: The majority of high-voltage burns was work-related (75 %). The mean total burn area was 35 % of the total body surface, with a mean of 29 % deep burns. An average of 4.8 +/- 4 operations were performed per patient (range: 1 - 23 operations). Surgical procedures included repeated debridement/necrectomy (100 % of all patients), early escharotomy/fasciotomy (47.5 %), and amputations (18 %). 14 patients (23 %) underwent reconstructive surgery using either local or free flaps. The mortality rate was 15 %. CONCLUSION: The surgical management of high-voltage burns is characterised by repetitive debridements and necrectomies. Despite an aggressive approach to remove necrotic tissue, the mortality in this type of injury is considerably high. Limb salvage may be achieved with the use of free microvascular flaps. However, an amputation of necrotic extremities must be considered in the copresence of septic complications.

Intramedullary headless screw fixation for fractures of the proximal and middle phalanges in the digits of the hand: a review of 31 consecutive fractures.

UNLABELLED: We present the results of 26 patients with 31 consecutive displaced or unstable extra-articular fractures of the base and shaft of the proximal and middle phalanges of the digits of the hand, treated over a period of 12 months with an intramedullary headless compression screw and early mobilization with no splinting. All fractures healed with no major complications. Only one patient, who had a pathological fracture through an enchondroma, required a tenolysis to improve the mobility of the finger. This technique seems to be technically simple, effective and with few drawbacks. LEVEL OF EVIDENCE: IV.

Long-term clinical outcome after epineural coaptation of digital nerves.

UNLABELLED: This study evaluates the long-term clinical outcome and complication rate after digital nerve repair in adults and aims to identify possible prognostic factors of sensory recovery. End-to-end epineural coaptation was performed under magnification. A total of 93 coapted digital nerves were clinically evaluated with a mean follow-up of 3.5 years (range 1-6 years). The mean two-point discrimination was 10.6 mm (versus 4.4 mm for the contralateral side). Cutaneous pressure threshold tested with Semmes-Weinstein monofilaments showed a mean value of 2.7 (versus 2.2 for the contralateral side). Only 2% of our patients developed painful neuromas. None of our patients recovered normal functional sensibility, however, recovery of protective sensation contributed to a high reported level of satisfaction. No correlation was observed between the sensory outcome and age, smoking, mechanism of injury, lesion to or anastomosis of a digital artery, or time of immobilization. The only identified predictor of the result was the surgeon's level of experience. This highlights the importance of adequate training and practice in the surgical repair of smaller peripheral nerves. LEVEL OF EVIDENCE: IV.

Sensitization and desensitization of burn patients as potential candidates for vascularized composite allotransplantation.

Sensitization describes the acquired ability of the immune system to react to foreign human leukocyte antigens (HLA) by producing antibodies and developing memory cells. In the field of transplantation, recipient preformed HLA antibodies due to previous sensitization have been identified - beneath ABO incompatibility - as a major factor for acute graft rejection. Several reasons for sensitization have largely been studied, such as previous blood transfusions, pregnancies or former transplants. Recent studies indicate that the use of assist devices (e.g. ECMO) or cadaveric skin allotransplantation providing temporary coverage in burn patients may lead to additional sensitization. As vascularized composite allotransplantation (VCA) has become a rapidly advancing therapeutic option for reconstruction of complex tissue defects in burns, it seems even more important to become familiar with immunological principles and to be cautiously aware of both sources of sensitization and therapeutic concepts in burns avoiding sensitization. This may also include emergency VCAs in burn patients as potential strategy for early definitive reconstruction avoiding procedures triggering HLA antibody formation. We hereby provide an overview on current evidence in the field of pre- and peritransplant sensitization, followed by posttransplant strategies of desensitization and their potential impact on future treatments of burn patients.

Extending the limits of reconstructive microsurgery in elderly patients.

BACKGROUND: Population aging strongly affects the demographic development of industrialized countries. While microsurgical procedures were initially believed to be only feasible in patients of younger age because of the duration of the surgical procedure and the higher risk of vascular insufficiency due to age-related comorbidities, it has become evident that these procedures are beneficial even for patients at an advanced age. METHODS: We retrospectively investigated microsurgical procedures in a patient cohort (n = 25 with 27 free flaps) with a minimum age of 78 years with regard to patients' characteristics, flap survival, and postoperative surgical and medical complications. RESULTS: Median age was 81 years (IQR 6). Most defects were located in the head and neck region. The mean operation time was 384 min (standard deviation (SD) 131). Flap failure was observed in three cases (11%). The median length of hospital stay was 17 days (interquartile range (IQR) 8). The mean ASA score was 2.48. Patients' age and ASA group did not correlate. The mortality rate was 4%. Postoperative surgical complications were observed in 11 cases (41%), while 19 patients (70%) showed one or more medical complications. Higher ASA classes tended to show more postoperative complications. However, neither age nor operating time nor ASA status showed significant influence on the occurrence of postoperative medical or surgical complications. CONCLUSION: There is growing demand for structural and functional restoration using free tissue transfer in an aging population. If there are no alternative treatment options available promising similar structural and functional preservation, free tissue transfer is justifiably in very old patients despite a potentially increased flap failure. As such, free tissue transfer is used as a curative treatment concept aiming at a maximum of patients' independence and early ambulation. Occurrence of complications can be diminished by adequate patient selection and thorough perioperative care.

Major burn injuries associated with Christmas celebrations: a 41-year experience from Switzerland.

In Switzerland it is customary to light candles on Christmas trees and advent wreaths. This tradition leads to an increased risk of home fires. We reviewed the records of patients who sustained burn injuries from a lit Christmas tree or advent wreath during the Christmas holidays between January 1971 and January 2012. We treated 28 patients and observed 4 fatalities (mortality rate: 14%). 61% of the patients were male, 39% were female. The mean abbreviated burn severity index (ABSI) was 6.5 points in the group of the survivors and 10.8 points in the group of the non-survivors. The mean total body surface area burned (TBSA) for survivors was 18.9%, with 14.1% having full thickness burns; for the non-survivors the mean TBSA was 45.2%, with 38% having full thickness burns. The Mann-Whitney U-test showed a significant difference between the survivors and the fatalities concerning the mean total and full thickness burned body surface area (p value 0.009 and 0.012). More than sixty percent of the fires occurred in January and the most severe accidents were seen after January 4th. Despite Christmas decoration-associated fires being relatively uncommon, they tend to cause more serious injuries than regular household fires. We recommend that in countries where it is customary to set up flammable Christmas decorations, state-issued information pamphlets with instructions on fire safety conduct should be distributed.

En Suisse il est de coutume de mettre des bougies allumées sur les arbres de Noël et sur les couronnes de l'Avent. Cette tradition aument le risque d'incendies de maison. Nous avons examiné les dossiers de patients ayant subi des brûlures causées par un arbre de Noël ou une couronne de l'Avent pendant les vacances de Noël entre Janvier 1971 et Janvier 2012. Nous avons traité 28 patients et observé 4 décès (taux de mortalité: 14%). 61% des patients étaient des hommes, 39% étaient des femmes. La moyenne "indice abrégée de gravité de la brûlure" était de 6,5 points dans le groupe des survivants et 10,8 points dans le groupe des décédés. La moyenne de la surface corporelle totale brûlée (SCT) pour les survivants était de 18,9% - avec 14,1% ayant des brûlures au troisième degré; pour les non-survivants la moyenne SCT était de 45,2% - avec 38% ayant des brûlures au troisième degré. Le test U de Mann-Whitney a montré une différence significative entre les survivants et les non-survivants qui concerne la totale moyenne et l'épaisseur total brûlé de la surface du corps (valeur p de 0,009 et 0,012). Plus de 60% des incendies a eu lieu en Janvier et les accidents les plus graves ont été observés après le 4 Janvier. Meme si les incendies associés aux décorations de Noël sont relativement rares, ils ont tendance à causer des blessures plus graves que les incendies domestiques réguliers. Nous recommandons que, dans les pays où il est d'usage de mettre en place des décorations de Noël inflammables, les brochures d'information soient distribués par l'état avec des instructions sur le comportement de sécurité.

Replantation by palmar arteriovenous anastomosis in complex finger amputations.

Digital replantation is a well-established and increasingly common procedure in specialized hand surgery units worldwide. Replantation after complex trauma is often challenging due to severely injured, small-diameter vessels, especially at the distal level. Digit salvage by arteriovenous anastomosis has been inadequately described in the literature for such cases. The objective of this study was to evaluate the outcomes and complications of arteriovenous digital replantation in complex amputations. We reviewed five cases of digital replantation using a single palmar afferent arteriovenous anastomosis and drainage via a dorsal vein. The postoperative protocol followed our standard replantation protocol. All digits survived with no revision procedures. No major complications were observed. One digit developed partial epidermolysis and one thumb developed marginal skin necrosis, both treated conservatively. The color of the replanted digits was not a reliable monitoring parameter but capillary refill was consistently visible. Microangiography performed four months after surgery demonstrated good digit perfusion. Our results support palmar arteriovenous anastomosis as a reliable alternative in digital replantation if distal arteries are unavailable for anastomosis. The results also suggest that this digit salvage procedure can be carried out at a more proximal level than previously reported.

Carpal tunnel syndrome: Analysis of online patient information with the EQIP tool.

Patients suffering from carpal tunnel syndrome (CTS) actively search for medical information on the Internet. The World Wide Web represents the main source of patient information. The aim of this study was to systematically assess the quality of patient information about CTS in the Internet. A qualitative and quantitative assessment of websites was performed with the modified Ensuring Quality Information for Patients (EQIP) tool that contains 36 standardized items. Five hundred websites with information on CTS treatment options were identified through Google, Bing, Yahoo, Ask.com and AOL. Duplicates and irrelevant websites were excluded. One hundred and ten websites were included. Only five websites addressed more than 20 items; quality scores were not significantly different between the various providing groups. A median of 15 EQIP items was found, with the top website addressing 26 out of 36 items. Major complications such as median nerve injury were reported in 27% of the websites and their treatment in only 3%. This analysis revealed several critical shortcomings in the quality of the information provided to patients suffering from CTS. There is a collective need to provide interactive, informative and educational websites for standard procedures in hand surgery. These websites should be compatible with international quality standards for hand surgery procedures.

[Intravascular MR imaging: the first in-vivo experiences in an animal arteriosclerosis model]. / Intravaskuläre MR-Bildgebung: erste in-vivo-Erfahrungen in einem Arteriosklerose-Tiermodell.

PURPOSE: To evaluate intravascular MR imaging in normal New Zealand rabbits and hereditary hyperlipidaemic Watanabe rabbits (WHHL) with histological correlation. MATERIAL AND METHODS: The suprarenal abdominal aortas of two normal and two WHHL rabbits were examined by conventional angiography, high resolution MRT with a surface coil and intravascular MRT in a 1.5 T system. The intravascular reception coil consisted of a copper wire loop built into the balloon of an angioplasty catheter. The findings were correlated with histological examinations. RESULTS: Excellent spin echo images with a resolution of 78 x 156 microns were obtained in less than 4 minutes. The arteriosclerotic changes in the vessels of the WHHL rabbits could not be recognised angiographically. High resolution MRT with surface coils showed mural thickening but a detailed demonstration of arteriosclerotic lesions was possible only by means of high resolution intravascular imaging. There was good histological correlation. CONCLUSION: Arteriosclerotic lesions can be demonstrated in vivo by high resolution intravascular imaging.

Quantification of functional results after facial burns by the faciometer.

In the present study the faciometer(R) is introduced in order to quantify the ranges of mimic movements observed after surgical treatment of facial burns. This instrument which consists of calipers and an electronic display was introduced in 1994 in order to measure the extent of facial palsy during reconstructive procedures. The study group consisted of 23 patients, who had been operated on for facial burns. The distances between standardised stable and moving points in the face were determined after mimic movements such as lifting of the eyebrows, maximum showing of the teeth and pursing of the lips. These distances were expressed as a percentage of the distance at rest. For comparison the scars were classified according to the Vancouver Scar Scale. In all patients the functional results after burn trauma in the face and, in some cases, asymmetries at rest could be objectified. Depending upon the severity of scarring, the distance between tragus and mouth was shortened between 0 and 19% after maximal showing of the teeth. In general the mouth region showed more functional deficits than the forehead. Comparing different manners of treatment, it could be objectively demonstrated that the results after deep burns requiring skin grafts were worse than those observed after more superficial lesions and other methods of coverage. The application of keratinocytes to close the burn showed highly variable results.

The qualification of different free muscle transplants to reconstruct mimic function: an experimental study in rabbits.

With the scutuloauricularis muscle, we developed a new model for experimental free transplantation of mimic muscles in the rabbit and studied the qualification of different muscles for free functional grafting into the position of the facial muscle, which is to be replaced. Forty adult female white New Zealand rabbits were distributed to four groups of 10 rabbits each. In group 1, the operative techniques of the new transplantation models were developed in the scutuloauricularis muscle, the pectoralis descendens muscle, and a comparable part of the rectus femoris muscle. In group 2, the scutuloauricularis muscle was transplanted orthotopically with microneurovascular anastomoses on the left side; in group 3, the pectoralis descendens muscle was transplanted into the position of the scutuloauricularis after its removal; and with the animals in group 4, a piece of the rectus femoris muscle was transplanted into the position of the mimic muscle after its removal. In all muscle transplants, the neurovascular supply was reestablished microsurgically by end-to-end anastomoses to the superficial temporal vessels and direct nerve coaptation to the facial nerve branches supplying originally the scutuloauricularis muscle. Nine months after transplantation, force measurements were performed in all transplanted muscles and the scutuloauricularis muscles of the control side. Cross-sections stained for ATPase after alkaline preincubation at pH 10.4 were used for computer-assisted planimetry of the muscle fibers. The orthotopically transplanted scutuloauricularis muscles reached with 2.84 (+/-1.04) N for maximal tetanic tension on the average 87.7 (+/-32.1) percent of that of the control scutuloauricularis muscles, the pectoralis descendens muscles with 4.25 (+/-2.15) N on the average 188.7 (+/-100.7) percent of that of the controls, and the pieces of rectus femoris muscles 6.62 (+/-2.16) N or 185.3 (+/-45.4) percent of that of the controls. All three muscles were identified as fast contracting muscles before and after transplantation. By transplantation, the content of type II muscle fibers changed from 58.2 to 68.0 percent in the scutuloauricularis muscle, from 62.4 to 74.4 percent in the musculus pectoralis descendens, and from 92.5 to 82.8 percent in the rectus femoris muscle. For the first time, an experimental model for free transplantation of mimic muscles was developed and functionally assessed. The most important result of this study was the fact that the double-sized muscle grafts developed twice the force of the control scutuloauricularis muscles, although reinnervated by the original muscle nerve branch. This result underlines the usefulness of overdimensioning during clinical muscle transplantation. It was also shown that parts of big muscles can be grafted with results similar to those experienced with complete smaller muscles.

Development of a new documentation system for facial movements as a basis for the international registry for neuromuscular reconstruction in the face.

None of the paresis scoring systems used satisfies an adequate description of all the details necessary to document the degree of facial paresis before and after any treatment. We developed a new documentation system considering all details of the history of the patient and of the treatment that could have any influence on the functional result. The third part of this "international registry for neuromuscular reconstruction in the face" concerns paralysis assessment, including quantitative measurements of the resting and moving face, besides qualitative parameters. A map of standardized static and dynamic points in the face was designed, and three-dimensional measurements of the movements of these facial points were performed with a VICON system in 16 healthy individuals. On the basis of the results, three real static points and representative dynamic points were selected as well as relations of these points most representative for the different facial movements. For data collection, a simple instrument (Frey's faciometer) was developed. A preliminary report is given on the clinical application of this new instrument.

Three-dimensional video analysis of facial movements: a new method to assess the quantity and quality of the smile.

The results of neuromuscular reconstructions of the paralyzed face are difficult to assess. Very sophisticated methods are necessary to measure the motor deficits of facial paralysis or the functional recovery in the face. The aim of this development was a relatively simple system for data acquisition, which is easy to handle and which makes it relatively cheap to delegate data acquisition to centers all over the world, which will not be able to derive a data analysis on their own, but will send their data to a center with specialized equipment. A complex mirror system was developed to get three different views of the face at the same time on the video screen. At each investigation, a digital video is taken from a calibration grid and from standardized facial movements of the patient. Secondary analysis of the digital videofilm is made possible at any time later on by the support of a computer program, which calculates distances and movements three-dimensionally from the frontal image and the right and left mirror images. Pathologies of the mimic movements can be identified as well as improvements after surgical procedures by this system. The significant advantage is the possibility to watch the same movement on the video which is under study and to apply any kind of study later on. Taking the video needs only a few minutes, and fatigue of the patient's mimic system is prevented. Measurements usually at the endpoints of the movements give excellent information on the quantity of the movement or the degree of the facial palsy, whereas the video itself is very informative regarding the quality of the smile. Specific computer software was developed for standardized three-dimensional analysis of the video-documented facial movements and for data presentation. There are options like two-dimensional graphs of single moving points in the face or three-dimensional graphs of the movements of all measured points at the same time during a standardized facial movement. By a comparison of the right- and left-sided alterations of specific distances between two points during the facial movements, the degree of normal symmetry or pathologic asymmetry is quantified. This system is more suitable for detailed scientific multicenter studies than any other system previously established. A very sensitive instrument for exact evaluation of mimic function is now available.

Functional and morphometric evaluation of end-to-side neurorrhaphy for muscle reinnervation.

This study was undertaken to quantify the effect of motor collateral sprouting in an end-to-side repair model allowing end organ contact. Besides documentation of the functional outcome of muscle reinnervation by end-to-side neurorrhaphy, this experimental work was performed to determine possible downgrading effects to the donor nerve at end organ level. In 24 female New Zealand White rabbits, the motor nerve branch to the rectus femoris muscle of the right hindlimb was dissected, cut, and sutured end-to-side to the motor branch to the vastus medialis muscle after creating an epineural window. The 24 rabbits were divided into two groups of 12 each, with the second group receiving additional crush injury of the vastus branch. After a period of 8 months, maximum tetanic tension in the reinnervated rectus femoris and the vastus medialis muscles was determined. The contralateral healthy side served as control. The reinnervated rectus femoris muscle showed an average maximum tetanic force of 24.9 N (control 26.2 N, p = 0.7827), and the donor- vastus medialis muscle 11.0 N (control 7.3 N, p = 0.0223). There were no statistically significant differences between the two experimental groups (p = 0.9914). The average number of regenerated myelinated nerve fibers in the rectus femoris motor branch was 1,185 +/- 342 (control, 806 +/- 166), and the mean diameter was 4.6 +/- 0.6 microm (control, 9.4 +/- 1.0 microm). In the motor branch to the vastus medialis muscle, the mean fiber number proximal to the coaptation site was 1227 (+/-441), and decreased distal to the coaptation site to 795 (+/-270). The average difference of axon counts in the donor nerve proximal to distal regarding the repair site was 483.7 +/- 264.2. In the contralateral motor branch to the vastus medialis muscle, 540 (+/- 175) myelinated nerve fibers were counted. In nearly all cross-section specimens of the motor branch to the vastus medialis muscle, altered nerve fibers could be identified in one fascicle distal and proximal to the repair site. The results show a relevant functional reinnervation by end-to-side neurorrhaphy without functional impairment of the donor muscle. It seems to be evident that most axons in the attached segment were derived from collateral sprouts. Nonetheless, the present study confirms that end-to-side neurorrhaphy is a reliable method of reconstruction for damaged nerves, which should be applied clinically in a more extended manner.