Muscle flap mass preservation with end-to-side neurorrhaphy: an experimental study

The authors examined the preservation of rat gracilis muscle flap mass after motor and sensory end-to-side neurorrhaphy. The rat gracilis muscle flap model was designed based on a previous study. Twenty-four Sprague-Dawley rats were divided into three groups. In Group 1 (n = 8), the flap was denervated by transecting the obturator nerve. In Group 2 (n = 8), the flap was reinnervated by coapting the proximal saphenous nerve to the distal obturator nerve. In Group 3 (n = 8), the flap was reinnervated by coapting the motor branch of the femoral nerve to the distal stump of the obturator nerve. At 6 months postoperatively, the gracilis muscle flaps were examined, harvested, and weighed individually. Results showed that the flaps with motor nerve reinnervation retained good bulk, with a weight of 634.0 +/- 65.1 gm, which was statistically significantly higher than the denervated group (457.5 +/- 125.3 gm, p < 0.01). However, muscle mass preservation in the sensory reinnervated group (606.9 +/- 209.1 gm) was not significantly different, compared to the denervated group. Histology revealed atrophic changes in the denervated group, compared to the sensory and motor-reinnervated groups. The authors concluded that muscle mass can be preserved by end-to-side nerve repair. Motor nerve reinnervation is able to better arrest atrophic changes of the muscle flaps.     

Secondary reconstruction of the extensor mechanism using part of the quadriceps tendon, patellar retinaculum, and Gore-Tex strips after proximal tibial resection

Competence of the extensor mechanism is the major determinant of functional outcome of patients after proximal tibia resection. A method of secondary reconstruction of the extensor mechanism using the middle third of the quadriceps tendon and the patellar retinaculum augmented with Gore-Tex strips and gastrocnemius flap is described. Between 1981 and 1997, 7 patients with extension lag greater than 20 degrees at least 1 year after the initial surgery underwent secondary reconstruction of the extensor mechanism. All patients were followed up for a minimum of 2 years. Full extension to an extension lag of 10 degrees was achieved in three patients, and an extension lag between 10 degrees and 20 degrees was achieved in 4 patients. All patients had good to excellent functional outcomes and reported no limitations in daily life activities.     

Initial experience with a new method for the dynamic assessment of pelvic floor function in women: the Kolpexin Pull Test

The aim of this study was to evaluate a newly developed, simple test for assessing pelvic floor muscular function in women. Pelvic floor strength in women with symptomatic pelvic floor dysfunction was evaluated with a newly developed assessment tool, the Kolpexin Pull Test, and compared to a clinically validated digital pelvic floor strength assessment scale (DPA). A 36-mm Kolpexin sphere was inserted into the vagina above the levator plate and connected to a digital tensiometer/force gauge. The force required to remove the sphere was recorded for three resting trials and three maximum pelvic floor contractions. Results of the DPA and Kolpexin Pull Test were analyzed using ANOVAs of contrast variables, intraclass correlations, and regression analyses. Twenty-one women participated in the study. Age range was 36–85 years, parity range was 2–5. All six trials required less than 5 min to perform in each patient. Intraperson maximum contraction data were correlated at 0.96 (95% CI: 0.91, 0.98), and were greater at higher DPA scores (p=0.016). There were positive correlations between the maximum contraction and DPA data (adjusted R²=0.52; p <0.001), and the maximum contraction minus resting vs DPA data (adjusted R²=0.54; p< 0.001). The Kolpexin Pull Test is reproducible, rapid, and correlates with digital clinical assessment of pelvic floor strength during maximal contractions.Abbreviations DPA Digital pelvic assessment - MC Maximum pelvic floor contraction - RP Relaxed pelvic floor Editorial Comment: This paper is an interesting pilot study of a new technique to measure pelvic muscle strength. Several other techniques have already been described. As the authors have stated, all methods have flaws, including the relatively easy and reproducible digital pelvic assessment (DPA). The Kolpexin sphere offers the hope of more objective testing than the DPA, overcomes the contribution of Valsalva to the pressure perineometry readings, and is easier to perform than ultrasound or EMG. The authors did not fully convince us of the objectivity of the measurements, as the study was not blinded. Also, we do not know whether the size of the sphere altered the readings in women in different heights and/or weights. If, on further testing, this technique is shown to have inter- as well as intraexaminer reproducibility, it may contribute to the evaluation of patients for management as well as for research.     

The role of AO external fixation in proximal femoral osteotomies in the pediatric neuromuscular population

Internal fixation in proximal femoral osteotomies using traditional devices may be sub-optimal in children with neuromuscular disorders who have small or osteopenic bone. In this population, between 1988 and 2000, we performed 36 proximal femoral varus osteotomies in 28 patients. These were controlled by the AO external fixator. The average age at surgery was 7 years (range, 2-13 years). A mean varus correction of 34 degrees (range, 15-90 degrees) was obtained. Complications consisted of one superficial pin tract infection, one skin breakdown, and one non-union. Other than the non-union, all osteotomies were stable at the time of the fixator removal. The AO external fixator is an effective alternative in maintaining corrective proximal femoral osteotomies in children with fragile bones.     

Effects of removal of the acetabular labrum in a sheep hip model

OBJECTIVE: The aim of this study was to learn whether partial resection of the acetabular labrum would lead to degenerative arthritis in an ovine model. METHODS: A 2 cm segment of labrum was removed from one hip in 18 mature Swiss Alpine sheep and a sham procedure was performed on the opposite side. Animals were permitted ad lib activity until sacrifice at 6, 12 or 24 weeks. The hip joint was removed en bloc, and loaded with a force of one body weight, using a custom device designed to recreate a physiologic joint reaction force. While under load, the joint was plunge frozen, and then fixed by freeze substitution using aldehydes in methanol/acetone solvents. The entire joint was embedded in methacrylate and sectioned in a standardized frontal plane following the reaction force and including the femoral neck and the acetabular fossa. The sections were evaluated for concentricity and evidence of arthrosis. Six hip joints of three sheep with no surgical procedure were loaded with high or low loads and served as non-surgical controls. RESULTS: Degenerative changes were present in all surgical hips, but the changes were symmetrical and mild. In 16 of 18 hips, the labrum regenerated to the extent that dense fibrous scar extending from the surgically denuded origin filled the defect. CONCLUSION: Resection of the labrum does not cause rapid degeneration or altered stability of the sheep hip.     

The early detection research network surface-enhanced laser desorption and ionization prostate cancer detection study: A study in biomarker validation in genitourinary oncology

Prostate-specific antigen (PSA) screening has led to a dramatic increase in prostate cancer detection with a concurrent stage migration. Although the test has revolutionized prostate cancer detection by identifying disease that is potentially curable in the majority of men, only 25% of men receiving test results of PSA > 4 ng/ml will have prostate cancer and many men receiving a normal PSA will have disease, including high-grade disease. There is a need for improved biomarkers for detecting prostate cancer. One such method of cancer detection is surface-enhanced laser desorption and ionization (SELDI). The Early Detection Research Network (EDRN) validation study for SELDI for prostate cancer is described. In a three-stage study, the portability and reproducibility of the technique will be determined; the predictive algorithm will be refined in a multi-institutional case-control population; followed by ultimate validation in the context of a prospective trial with complete disease ascertainment. The unique aspect of the EDRN SELDI validation study is the novel use of two groups of cancer cases: those cases with higher-risk disease (Gleason > or = 7) and those cases with lower-risk disease (Gleason < or = 6). This study will allow the first evaluation of a predictive algorithm that includes prognosis in disease screening. The EDRN SELDI prostate cancer biomarker validation study is a rigorous evaluation of a new detection method for prostate cancer. The methodologies used for this evaluation will prove useful for guiding future biomarker studies in this challenging disease.     

Vesicovaginal fistula resulting from loop electrosurgical excision in a woman with intraepithelial neoplasia of the cervix and vagina: a case report

A 52-year-old woman had concomitant cervical intraepithelial neoplasia (CIN) grade 3 and vaginal intraepithelial neoplasia grade 3. On performing a loop electrosurgical excision procedure, a vesicovaginal fistula accidentally occurred. The vaginal intraepithelial neoplasia covering the anterior fornix could have been a contributing factor in the occurrence of the fistula.     

Efficient replication of full-length murine leukemia viruses modified at the dimer initiation site regions

Retroviruses encapsidate two copies of full-length viral RNA molecules linked together as a dimeric genome. RNA stem loop structures harboring palindromic (or "kissing") loop sequences constitute important cis-elements for viral dimerization known as dimer initiation sites (DIS). In murine leukemia virus (MLV), a 10-mer and a 16-mer palindrome (DIS-1 and DIS-2, respectively) located in the viral leader region mediate dimerization in vitro and affect dimer stability of vector RNA in vivo. We have investigated the effect on viral replication of introducing deletions or nucleotide substitutions within these palindromes in a full-length MLV genome. Our results demonstrate that viruses modified at the dimer initiation site regions are viable and show wild-type levels of RNA encapsidation. One mutant lacking the DIS-1 palindrome was severely impaired and displayed an increased cellular ratio of spliced versus genomic RNA that most likely contributes to the inefficient replication. The implications for development of DIS-modified retrovirus-based vectors are discussed.     

Effects of breastfeeding chemosignals on the human menstrual cycle

BACKGROUND: To date, there has not been an investigation to determine whether lactating women and their infants influence the ovarian function of other women with whom they interact. METHODS: In a randomized, double-blind, placebo-controlled study of 47 nulliparous women, we utilized both within- and between-subjects controls to assess the effects of sustained exposure to breastfeeding compounds on menstrual cycle length, as well as characteristics of each phase of the ovarian cycle. RESULTS: Breastfeeding compounds modulated ovarian cycle length in comparison with the carrier control (0.01 < or = all P values < or = 0.05), disrupting the normal homeostatic regulation of cycle length and tripling its variance. Hence, women with long cycles stayed long and did not regress to the mode of 29 days and women with short cycles maintained short cycles. This effect was driven by changes in both the follicular and luteal phases of the cycle (0.01 < or = all P values < or = 0.04) and changed the timing of the pre-ovulatory surge of LH. CONCLUSIONS: Because compounds from lactating women and their infants modulated the ovarian cycles of women, as is seen in other mammals, they have the potential to function as pheromones, regulating fertility within groups of women.