Age-specific differences in the time-frequency representation of surface electromyographic data recorded during a submaximal cyclic back extension exercise: a promising biomarker to detect early signs of sarcopenia.

PURPOSE: Motivated by the goal of developing new methods to detect early signs of sarcopenia, we investigated if surface electromyographic (SEMG) data recorded during the performance of cyclic, submaximal back extensions are marked by age-specific differences in their time and frequency characteristics. Furthermore, day-to-day retest reliability of the EMG measures was examined. METHODS: A total of 86 healthy volunteers used a back dynamometer to perform a series of three maximal voluntary contractions (MVC) consisting of isometric back extensions, followed by an isometric back extension at 80% MVC, and finally 25 slow cyclic back extensions at 50% MVC. SEMG data was recorded bilaterally at L1, L2, and L5 from the iliocostalis lumborum, longissimus, and multifidus muscles, respectively. Tests were repeated two days and six weeks later. A linear mixed-effects model with fixed effects "age, sex, test number" and the random effect "person" was performed to investigate age-specific differences in both the initial value and the time-course (as defined by the slope of the regression line) of the root mean square (RMS-SEMG) values and instantaneous median frequency (IMDF-SEMG) values calculated separately for the shortening and lengthening phases of the exercise cycles. Generalizability Theory was used to examine reliability of the EMG measures. RESULTS: Back extensor strength was comparable in younger and older adults. The initial value of RMS-SEMG and IMDF-SEMG as well as the RMS-SEMG time-course did not significantly differ between the two age groups. Conversely, the IMDF-SEMG time-course showed more rapid changes in younger than in older individuals. Absolute and relative reliability of the SEMG time-frequency representations were comparable in older and younger individuals with good to excellent relative reliability but variable absolute reliability levels. CONCLUSIONS: The IMDF-SEMG time-course derived from submaximal, cyclic back extension exercises performed at moderate effort showed significant differences in younger vs. older adults even though back extension strength was found to be comparable in the two age groups. We conclude that the SEMG method proposed in this study has great potential to be used as a biomarker to detect early signs of sarcopenic back muscle function.

Microduplications encompassing the Sonic hedgehog limb enhancer ZRS are associated with Haas-type polysyndactyly and Laurin-Sandrow syndrome.

Laurin-Sandrow syndrome (LSS) is a rare autosomal dominant disorder characterized by polysyndactyly of hands and/or feet, mirror image duplication of the feet, nasal defects, and loss of identity between fibula and tibia. The genetic basis of LSS is currently unknown. LSS shows phenotypic overlap with Haas-type polysyndactyly (HTS) regarding the digital phenotype. Here we report on five unrelated families with overlapping microduplications encompassing the Sonic hedgehog (SHH) limb enhancer ZPA regulatory sequence (ZRS) on chromosome 7q36. Clinically, the patients show polysyndactyly phenotypes and various types of lower limb malformations ranging from syndactyly to mirror image polydactyly with duplications of the fibulae. We show that larger duplications of the ZRS region (>80 kb) are associated with HTS, whereas smaller duplications (<80 kb) result in the LSS phenotype. On the basis of our data, the latter can be clearly distinguished from HTS by the presence of mirror image polysyndactyly of the feet with duplication of the fibula. Our results expand the clinical phenotype of the ZRS-associated syndromes and suggest that smaller duplications (<80 kb) are associated with a more severe phenotype. In addition, we show that these small microduplications within the ZRS region are the underlying genetic cause of Laurin-Sandrow syndrome.

[Epiphyseal Bar Resection for Correction of Clinodactyly]. / Resektion der atypischen Wachstumsfuge zur Korrektur der Klinodaktylie.

BACKGROUND: Clinodactyly is a digital angulation in the radio-ulnar plane. Mostly it is seen on the little finger. The middle phalanx typically has a triangular or trapezoid shape (delta phalanx), resulting in radial deviation of the distal phalanx. Resection of the longitudinal epiphyseal bracket (physiolysis) with fat graft interposition is a possible surgical technique, which uses children's growth potential to correct the axial deviation. AIM: The purpose of our study was to review the degree of correction at least 2 years postoperatively and after an average of 5 years postoperatively, and to find out if children´s age influences the results. PATIENTS AND METHODS: 23 children (43 little fingers) underwent physiolysis and were retrospectively analyzed after a median follow-up of 5 years (2.1-7.9 years). The active range of motion of the little finger's MP, PIP and DIP joints and finger-palm-distance were measured. Lateral deviation was determined by using standardized radiographs and subsequently compared with preoperative values. Patients were divided into 2 subgroups: younger than 3 years (16 fingers, group A), older than 3 years (27 fingers, group B). The achieved correction of the lateral deviation was compared between both groups. RESULTS: All patients showed full active range of motion in all joints of treated fingers. Finger-palm-distance was 0 cm. No complications occurred. The mean preoperative deviation of all patients was 37°±11, which improved after surgery by 17°±11 (i. e. 44.0%±23.1 of initial findings). Group A demonstrated a mean preoperative lateral deviation of 40°±9, and group B a mean deviation of 36°±12. In both groups we saw a similar improvement (group A mean: 17°±10, group B mean: 17°±11). In group A there was a wider dispersion of postoperative results. In the age group 7 to 10, the results of individual cases show the large variability of the corrective potential. X-rays revealed the following incidental findings after surgery: a premature fusion of the proximal radial epiphyseal plates in 2 fingers and a sinuous-shaped proximal radial epiphyseal plate in 12 other fingers. CONCLUSION: Resection of the longitudinal epiphyseal bracket with fat graft interposition is a technically simple and effective treatment option for clinodactyly, particularly in children of 3 to 6 years of age.

[Distraction Osteogenesis is an Effective Method to Lengthen Digits in Congenital Malformations]. / Die Kallusdistraktion ist eine effektive Methode zur Fingerverlängerung bei angeborenen Fehlbildungen.

PURPOSE: The aim of this study was to investigate the feasible amount of lengthening by distraction osteogenesis in congenital hand deficiencies. PATIENTS AND METHODS: A total of 60 patients (1.6-17.8 years) underwent lengthening of 71 bones between 1994 and 2014. Bone lengthening was performed on 46 metacarpals and 25 phalanges. Mostly the first (n=30) and the fifth (n=21) rays were lengthened. Bone lengthening was performed to treat primarily symbrachydactyly (b=32) and amniotic band syndrome (n=10). To analyze the amount of lengthening preoperative radiographs and radiographs taken while removing the external fixator were compared. The charts were reviewed regarding age at surgery, duration of lengthening, duration of bony consolidation, complication, etc. RESULTS: The average of metacarpal distraction was 18.4 mm=73% lengthening with respect to the preoperative length; the average of phalange distraction was 14.0 mm=77% of the preoperative length. In both, metacarpals and phalanges, a lengthening of > 100% of the preoperative bone length was possible. In target length was reached in 89% of the procedures. The average time for consolidation was 6.1 (1-20) days/mm lengthening. The external fixator was in use on average for 140 (50-346) days. After removing of the external fixator an axial K-wire was used to stabilize the callus in 9 procedure, and an iliac bone craft plus axial K-wire in 11 procedures. The rate of complications was 30% (early consolidation, deviation, joint dislocation, pin infection, tendon dislocation). All complications could be treated without with acceptable results. CONCLUSION: Metacarpal and phalangeal distraction lengthening is an effective but demanding technique for ray reconstruction in congenital malformations of the hand. It is possible to lengthen a bone by more than 100%. Complications are common, but in most cases easy to handle.

Transverse soft tissue distraction preceding separation of complex syndactylies.

UNLABELLED: Various surgical techniques are described for separation of syndactylies leading to good results. However, the use of standard techniques is limited in complex syndactylies with extensive bony fusion and tight soft tissues. The aim of this study was to assess the outcomes of a two-stage procedure involving progressive soft tissue distraction prior to syndactyly release. Between 1996 and 2012 we treated 168 complex syndactylies with this technique. The main indications were syndactylies in Apert syndrome. The digits were distracted through an external fixator at 0.5 mm/day. Distraction of 15-25 mm was achieved. Soft tissue distraction provided additional skin, a wider nail matrix and more bone in the form of callus. Thus subsequent modelling of the fingertips was improved, especially if they were closely fused. This technique facilitates treatment of complex cases and improves aesthetic outcome. LEVEL OF EVIDENCE: Therapeutic IV.

A clinically weighted approach to outcome assessment in radial polydactyly.

UNLABELLED: Currently available outcome assessment systems for radial polydactyly are mainly based on expert opinion. The aim of this study was to develop an outcome assessment system based on clinical data. We performed linear regression analysis on data from a multicentre study of 121 patients with radial polydactyly types II, IV and VII to develop a clinically weighted outcome assessment system. Items were weighted according to their influence on overall functional and aesthetic outcome in the regression analysis. Active flexion, scar appearance and prominence at amputation site were the main items influencing overall functional and aesthetic outcome (ß = 0.393, ß = 0.326 and ß = 0.288, respectively). Palmar abduction, metacarpophalangeal joint deviation and nail appearance influenced overall functional and aesthetic outcome the least (ß = -0.002, ß = -0.104 and ß = 0.070, respectively). Our proposed assessment system for radial polydactyly reflects the way clinicians value individual aspects of outcome as determinants of overall outcome and helps guide future treatment and evaluation of outcome. LEVEL OF EVIDENCE: III.

[Therapy of the peromelic form of symbrachydactyly by double second-toe transplantation]. / Die Behandlung der peromelen Form der Symbrachydaktylie durch zweifache freie Zehentransplantation.

From 1989 to 2001 eleven children with the peromelic type of symbrachydactyly underwent a staged double second toes transplantation for restoration of two finger rays. The second toe of the feet were transplanted first to the small finger position and in the second step to the thumb position. One failure occurred in the first toe transplantation and another developed a venous thrombosis with partial necrosis and eventually a useless ray. Eight children were reviewed retrospectively in a mean follow-up of 5.3 years. The ability to pinch was restored in four children. In all patients without complications the function of the hand improved and the sensitivity was good.

Ten-year experience with one-step correction of constriction rings by complete circular resection and linear circumferential skin closure.

BACKGROUND: In amniotic band syndrome (ABS) constriction rings affecting the limbs are regularly seen at birth. Circular resection and closure with multiple Z-plasties has been described as the treatment of choice. However, direct circular closure creating linear circumferential scars might replace multiple Z- or W-plasties to reduce scars and improve aesthetic outcome. METHODS: From 2000 to 2009 we treated 160 patients with ABS. In 43 cases release of isolated constriction rings was performed by circular excision and closure. Constriction rings were completely resected and skin closure could be performed without Z-plasty in all cases. Data from follow-up of all cases were reviewed and photographs and recordings reassessed. The median age at operation was 14.3 months (range 2-32). Constriction rings were localised on the upper arm in five patients, the lower arm in five, the wrist in two and at the metacarpal level in five. At the lower extremity the thigh was affected in three and the lower leg in 23 patients. RESULTS: In the 16 cases of the first treatment period from 2000 to 2004, average follow-up was 6.5 years (range 5.1-10.3). We observed two minor complications following 43 operations (wound dehiscence and secondary healing). No formation recurrence of banding was seen. Aesthetic outcome was overall good. CONCLUSIONS: We found excellent aesthetical and functional results following change of treatment from multiple Z-plasties to linear circumferential closure. Scars were generally less noticeable and no recurrence or scar constriction could be detected with growth. However, radical excision of all constricting tissues prior to wound closure is mandatory.

[Return of sensitivity after digital nerve reconstruction in children: how does age affect outcome?]. / Sensibilitätsrückkehr nach kindlichen Nervenverlet-zungen der Hand - welche Rolle spielt das Patientenalter?

BACKGROUND: The regenerative capacity after nerve reconstruction in children is believed to be superior compared to that in adults. However, the available data on this topic are limited. The aim of this work is to improve the age-dependent assessment of the prognosis after surgical treatment of peripheral nerve injuries of the hand. PATIENTS AND METHODS: 44 of 147 children with complete transections of proper and common digital nerves who were treated from 2000 to 2009 and who were currently 6 years or older, could be included for follow-up (mean time, 7.5 years). In total there were 60 nerve injuries, of which 56 were directly coaptated, 4 needed grafting. Sensitivity of the fingertips was assessed using the 2-point discrimination (2PD) test and the Semmes-Weinstein monofilament test. We also recorded hypersensitivity, sensitivity to cold, and paresthesia. To account for inter-individual differences in normal 2PD, the difference of the 2PD to the uninjured contralateral side was calculated as delta-2PD. The age at the time of the injury, divided into groups of 0-5, 6-10 and 11-15 years was correlated with the clinical outcome (2PD, monofilamenttest). Taking into account the results classified by age presented by Lohmeyer et al. and Mailänder et al., we assessed the correlation between age at injury (0-85 years) and clinical outcome. RESULTS: After 52 of the 56 direct nerve coaptations (93%) normal sensitivity was found with a 2PD<6 mm, 4 times the 2PD was 6 mm. Following nerve grafting a static 2PD of 6-7 mm was measured. Disturbing paresthesia, sensitivity to cold or hypersensitivity were not reported by any patient. The 2PD of the fingers of the opposite uninjured side showed great inter-individual differences. Patient's age and 2PD significantly correlated with significantly poorer results already in the second decade of life. CONCLUSION: In relation to adults, children have an excellent prognosis after nerve reconstruction. The high inter-individual differences in regular sensitivity, depending on age, co-morbi-dities, etc., suggest putting the results of the injured and uninjured sides into relation. Estimation of the Δs2PD may solve this -problem.

[Severe side effects after Octenisept irrigation of penetrating wounds in children]. / Schwere Nebenwirkungen nach Octenisept-Spülung von Perforationswunden im Kindesalter.

BACKGROUND: Deep penetrating wounds in children's hands are repeatedly treated in emergency wards conservatively through irrigation, antibiotic therapy and splint immobilisation. After we had seen severest phlegmonous reactions after irrigation with Octenisept followed by long troublesome histories we would like to warn against using this antiseptic agent for irrigation of wounds. We give an overview about the significance of antiseptics and the use of antibiotics in the treatment of deeper contaminated wounds. PATIENTS AND METHODS: Between 2003 and 2007, 5 children (aged 2 to 8 years) were treated for sequelae of local wound irrigation with Octenisept in perforating hand injuries. We describe the early and medium-term aspects after irrigation, the further development, therapeutic measures, long-term damages and necessary reconstructions. We present the results of bacteriological smear tests, laboratory reports and histological examinations as well as allergy tests. RESULTS: All children showed more or less identical hand appearances. Hands were swollen caused by an interstitial oedema, compartment pressures were increased and hand function was completely suspended. The oedemas persisted for weeks and were hardly controllable. Especially serious were injuries at thenar level and in the first web space. Long-term sequelae were contractures caused by fibrotic muscle changes. Neither through bacteriological nor histological analysis were hints of bacterial or viral infections found. An allergic reaction to Octenisept could be excluded in the 3 most heavily affected children by an ROAT test. CONCLUSION: To prevent damage, contaminated wounds should be operatively debrided and not be irrigated with an antiseptic liquid. Octenisept seems to have a toxic effect in non-distinguished tissue. Because of a slow resorption it remains for a long time in the tissue. For therapy we recommend fasciotomy of the mid-hand and probably finger compartments, followed by compression treatment, physiotherapy with lymphatic drainage, dynamic and static splints.

[Congenital lymphangioma of the lung]. / Kongenitales Lymphangiom der Lunge.

A congenital lymphangioma of the lung in a newborn is described for the first time. The aetiology and pathogenesis are discussed and various aspects of differential diagnosis considered.

[Hypospadias in the female]. / Die Hypospadie beim Mädchen.

Female hypospadias is a rare, but well defined anomaly of the lower urogenital system. From an embryologic point of view it represents an arrest during a late stage of sinus urogenitalis development. It is not to be confused with minor variants of the external urethral meatus of a doubtful clinical relevance. The main symptom is a severe subvesical obstruction, and usually it presents early in infancy. A case is presented, in which on the basis of the incorrect diagnosis of "occult neurogenic bladder outlet obstruction" a supravesical diversion (ileal conduit) was done. Undiversion was successfully carried out at an age of 7 years.

Infants with posterior urethral valves: a retrospective study and consequences for therapy.

This is a report on the follow-up data of 18 patients with posterior urethral valves diagnosed during the first year of life. One infant died of progressive renal failure; a slight elevation of serum creatinine levels in three children aged 4-6 years indicated a doubtful prognosis. On initial examination, ten patients showed severe unilateral or bilateral reflux. Seven of 14 refluxing units remained non-functioning and had to be removed. Following transurethral fulguration of the valves, five infants developed unilateral or bilateral reflux which was not evident on initial preoperative voiding cystograms. In contrast to those in other series, none of these refluxes ceased spontaneously. Ureteral reimplantations were done on 11 ureters of eight patients, but regression of ureteral dilatation postoperatively remained unsatisfactory in six instances, none of whom had a true mechanical obstruction. We conclude that many of these megaloureters encountered in infants with posterior urethral valves are concomitant with profound and often irreversible damage of the ureter wall. Surgery of such ureters, therefore, should be avoided whenever feasible.

[Spontaneous regression of neonatal ovarian cysts. A prospective study]. / Spontane Regression von neonatalen Ovarialzysten. Eine prospektive Studie.

With routine use of ultrasonography in pregnancy and newborns neonatal ovarian cysts are discovered more often. In view of the risk of possible complications they still pose a therapeutic problem. Frequent observations of their spontaneous regression suggest a conservative treatment. From 1988 to 1991 we investigated 21 newborns with the sonographic diagnosis of an ovarian cyst. In three children the cysts were resected primarily because of clinical symptoms or uncertain diagnosis. 18 children were controlled regularly by ultrasound. One of these had a mesenteric cyst, which had to be removed at the age of four months. In the others a complete resolution of all 19 ovarian cysts could be documented after intervals of up to 16 months. In these patients a clinically relevant complication did not occur. Therefore a conservative strategy with regular ultrasound controls is justified in all children with uncomplicated neonatal ovarian cysts. A surgical intervention is indicated only in case of complications or uncertain diagnosis.

[Reconstruction of the esophagus and hypopharynx by free jejunum interposition]. / Die Rekonstruktion des Oesophagus und Hypopharynx durch das freie Jejunum-Interponat.

Beside conventional procedures the hypopharyngeal and esophageal reconstruction using a free jejunum-transfer represents an additional method for primary reconstruction of the hypopharynx and esophagus. Out of 48 free jejunum-transfers 16 were used for bridging an hypopharyngeal or esophageal defect, 32 as a patch for reconstruction of the oral cavity. In 7 patients a hypopharynx carcinoma was resected, in 6 cases the cervical esophagus was infiltrated by carcinoma. 3 patients suffered from an esophageal stenosis caused by corrosion after acid ingestion. 11 free grafts healed without any complications. In 2 cases the jejunum was removed because of necrosis. In 3 cases fistulation from the lower anastomosis was observed. Free, microvascular jejunum-transfer using physiological graft material not only seems to be advantageous for tolerance to radiation but is also a one step surgical procedure.

[Multicystic kidney dysplasia]. / Die multizystische Nierendysplasie.

The clinical course of 48 children (27 boys and 21 girls) with multicystic kidney dysplasia was analysed retrospectively. The patients were seen and treated at the Children's Hospital of Medical School Hannover between 1976 to 1989. There was no familial occurrence of the disease, yet in eight families various other renal diseases could be observed. In 20 patients the diagnosis of multicystic renal dysplasia was presumed by prenatal sonographic examination, in the other patients the diagnosis was established at the age between 1 day to 12 years. The first manifestations were palpable abdominal mass (n = 16), urinary tract infection (n = 4), casually because of a sonographic evaluation for other reasons (n = 4) and vomiting (n = 2). Associated malformations were found in 18 patients: cardiac malformations (n = 6), dysplasia of the other kidney (n = 5), ureter obstruction of the other kidney (n = 3), horseshoe kidney (n = 1) and others (n = 3). There was no hypertension and serum creatinine levels were normal in those children, who did not suffer from associated malformations of the other kidney. The multicystic kidney was removed operatively in 42 patients at the age of 3 days to 9.5 years (median 4 weeks). The prognosis of multicystic kidney dysplasia depends on associated renal and other malformations.