The Development of Skeleton and Musculature of Shoulder Girdle and Forelimbs
John Gerhart, Marc Kirschner in Normal Table of Xenopus Laevis (Daudin), 2020
At stage 40 a thickening of the ectoderm, the anlage of the future forelimb atrium, appears dorso-caudal to the third visceral cleft. This thickening grows out in a dorso-caudal direction, forming a club-shaped protrusion into the mesenchyme at stage 41. At stage 53 the pars zonalis can again be divided into a dorsal pars scapularis and a ventral pars coracoidea, out of which the scapular and coracoidal regions of the shoulder girdle will develop. At stage 59 the two sternal anlagen appear as thickened patches of blastematous tissue in the ventral aponeurosis, where they are situated lateral to the processus epicoracoidei. At stage 55 the ventral edge of the pars zonalis tapers out into a thin strand of blastematous tissue, the anlage of the future ventral aponeurosis, which will later serve as the place of origin of the hypaxonic zonal muscles.
Hernia and hydrocele
Brice Antao, S Irish Michael, Anthony Lander, S Rothenberg MD Steven in Succeeding in Paediatric Surgery Examinations, 2017
The superficial inguinal ring is a defect in the aponeurosis of external oblique, located above and medial to the pubic tubercle. An indirect hernia passes through the deep inguinal ring and along the inguinal canal into the scrotum, while a direct hernia bulges through the posterior wall of the canal medial to the inferior epigastric artery through Hesselbach's triangle. A femoral hernia occurs through the femoral canal, which is the medial compartment of the femoral sheath, and is entered via the femoral ring. After hernia repair, scrotal swelling may develop as a result of fluid accumulating in the distal sac, forming a hydrocele. A hydrocele is a collection of fluid in the space surrounding the testicle between the layers of the tunica vaginalis. Hydroceles may be communicating or non-communicating. A hydrocele that was not present at birth, or that dramatically changes in size or fluctuates in size, is suggestive of a patent processus vaginalis.
Birth Injuries, Neonatal
Tony Hollingworth in Differential Diagnosis in Obstetrics and Gynaecology: An A-Z, 2015
Birth injury could be caused by trauma during the birth process or by perinatal conditions that lead to fetal hypoxia, or both. Birth injuries may be avoidable by obstetric intervention, or may be completely unavoidable. Caput succedaneum is a diffuse subcutaneous, extra-periosteal fluid collection with poorly defined margins. Unlike a cephalohaematoma, it can extend across the suture lines and the midline. It can be caused by the pressure of the presenting part against the birth canal or by vacuum extraction. Subgaleal haemorrhage is a collection of blood between the periosteum and the aponeurosis. About 77 per cent of cases follow an instrumental delivery. Cephalohaematoma is a subperiosteal collection of blood caused by the rupture of vessels beneath the periosteum. It is normally limited to the surface of one cranial bone, usually the parietal or occipital bone. Palpation of an organised cephalohaematoma gives an impression of ‘scalloping’ at the margins.
Evaluation of the eyebrow position after aponeurosis advancement
Published in Journal of Plastic Surgery and Hand Surgery, 2019
Kenichi Kokubo, Nobutada Katori, Kengo Hayashi, Jun Sugawara, Seiko Kou, Akiko Fujii, Syou Kitamura, Ryunosuke Ninomiya, Jiro Maegawa
Patients often develop eyebrow drooping after blepharoplasty or ptosis repair. After aponeurosis advancement was performed in 53 patients (100 eyelids) with blepharoptosis, the eyebrow heights at the medial canthus, center of the pupil, and lateral canthus were measured using scanned photographs obtained preoperatively and 3 months postoperatively. In the 100 eyelids subjected to aponeurosis advancement, the eyebrow position was lowered at the medial canthus in 81 eyelids (81%), at the center of the pupil in 84 eyelids (84%), and at the lateral canthus in 80 eyelids (80%). The mean distance of eyebrow drooping in the 100 eyelids was 2.80 mm at the medial canthus, 2.87 mm at the center of the pupil, and 2.50 mm at the lateral canthus. The preoperative margin reflex distance (MRD) was significantly associated with the distance of eyebrow drooping at the medial canthus, the center of the pupil, and the lateral canthus in the 100 eyelids, but the postoperative MRD was not significantly associated with these parameters in the 100 eyelids. In conclusion, eyebrow drooping developed after aponeurosis advancement in most cases, and the distance of eyebrow drooping was associated with the severity of blepharoptosis.
Levator Aponeurosis Sandwich Flap for Reconstruction of Upper Eyelid Defect
Published in Orbit, 2012
Hyera Kang, Yasuhiro Takahashi, Masayoshi Iwaki, Hirohiko Kakizaki
A 72-year-old woman suffered from a sebaceous gland carcinoma on her left upper eyelid. The tumour was 13 × 5 mm without metastasis. The tumour was excised with a 5-mm safety margin, resulting in a large, full-thickness defect in which almost all of the tarsal plate, approximately half of the orbicularis oculi muscle, and part of the levator aponeurosis were lost. Reconstruction of the upper eyelid was successfully performed with a levator aponeurosis sandwich flap, upon which the posterior lamella was covered by a free tarsal graft with medial and lateral periosteal flaps, and a skin graft from the contralateral upper eyelid for the anterior lamella. No lagophthalmos was demonstrated after the operation. Six months postoperatively, there was no tumour recurrence, no ocular complications, and good cosmetic results.
Foot Motion Character During Forward and Backward Walking With Shoes and Barefoot
Published in Journal of Motor Behavior, 2020
Dong Sun, Gusztáv Fekete, Julien S. Baker, Yaodong Gu
Backward walking (BW) has been extensively used in athletic training and orthopedic rehabilitation as it may have value for enhancing balance. This study identified the differences in foot intersegment kinematics (forward walking (FW) vs. time-reversed BW) and plantar pressure parameters of 16 healthy habitually shod individuals walking FW and BW using flexible shoes (SH) and under barefoot conditions (BF). BW was found to have shorter stride length (SL) and higher stride frequency (SF) under BF conditions compared with SH, which indicates a better BW gait stability under BF conditions. Decreased HX/FF dorsiflexion at HO in BW induces less plantar aponeurosis tension which may inhibit the windlass mechanism compared to FW walking. Increased forefoot relative to hindfoot (FF/HF) pronation and sequentially hindfoot relative to tibia (HF/TB) eversion combined with medially distributed plantar pressure and a higher plantar contact area in the medial side in BW–BF maybe beneficial in maintaining balance. These results indicate that BW training may be more reliable under BF conditions compared to the SH conditions based on greater sensory information feedback from the plantar area resulting in better biomechanical behavior.