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The objective of this experimental animal study was to compare the surgical precision of a flexible CO 2 laser fiber with that of monopolar electrosurgery in porcine myometrium. The subjects were 6 live adult non-pregnant female pigs. Linear injury to the uterine horns was created using a flexible CO 2 laser fiber at 5W, 10W, and 15W and with monopolar electrosurgery at 10W, 20W, 30W, and 40W in both cut and coagulation modes. Hysterectomy was then performed in the live animals. Cross-sections of the tissue were processed and stained using Masson trichrome to differentiate damaged from undamaged myometrium. Measurement means were compared using analysis of variance with Tukey honest significant difference correction; p <.05 indicated significance. Incision width of the laser at 5W and 10W was significantly less than both monopolar coagulation at all power settings and monopolar cut at 30W and 40W (all p <.01), at 5W was also significantly less than monopolar cut at 10W (p = .03), and at 15W was significantly less than monopolar coagulation at 40W (p = .001). Incision depth of the laser at 5W was significantly less than monopolar coagulation at 40W and laser at 15W (both p = .01), at 15W was significantly greater than monopolar coagulation at 10W and monopolar cut at 10, 20, and 30W (p ≤.01), and increased proportional to power for all 3 energy types. Collateral thermal damage width at all laser power settings was significantly less than at all monopolar coagulation power settings (p ≤.04) with the exception of the laser at 15W compared with monopolar coagulation at 10W (p = .30), and at all laser power settings was significantly less than at all monopolar coagulation power settings (p <.001). Collateral thermal damage depth of the laser at 5W and 10W was significantly less than monopolar cut at 30W (p ≤.002) and increased proportional to power in monopolar coagulation mode but remained constant with the laser. Incising efficiency of the laser at 5W was significantly greater than monopolar coagulation at 10W (p = .04), at 10W was significantly greater than at all monopolar power settings (p ≤.007) except cut at 40W (p = .29), and at 15W was significantly greater than that of every other energy type and power setting tested (p ≤.04). These findings support the hypothesis that CO 2 laser energy delivered via a flexible fiber system would exhibit greater surgical precision than monopolar electrosurgery, in both cut and coagulation modes, as defined by 3 parameters: incising efficiency, changes in incision depth compared with width as power increases, and variability in the resulting incision measurements. Because increased thermal damage has been associated with delayed tissue necrosis and adhesion formation, these findings prompt the design of a comparative survival animal study to assess additional clinically relevant parameters. [ABSTRACT FROM AUTHOR]

Summary: Background: Negative pressure wound therapy (NPT) has achieved widespread success in the treatment of difficult wounds. However, its effects are but partially explored, and investigations mostly concentrated at the wound–dressing interface; a detailed histological description of the evolution of wounds under NPT is still lacking. Materials and Methods: Subsequent punch biopsies of NPT-treated chronic wounds of human patients were analysed. Phenomena occurring in wounds were quantified by analysis of proliferating cells nuclear antigen (PCNA) (proliferating nuclei), CD31 (blood vessels), CD68p (macrophages) and CD45 (lymphocytes) stained slides. Results: Three layers were identified in day-0 wounds. Over time, under NPT, the layers behaved differently: the most superficial (1.5 mm) developed granulation tissue, constant in thickness, with high proliferation index, increased in blood vessels density and developed acute inflammation. Instead, the two deeper layers decreased in proliferation rate, maintained vessels density unchanged, were cleared of chronic inflammation and oedema and underwent progression towards stable tissue. Discussion: Indeed, while most research has focused on induction of superficial granulation tissue by NPT, deeper layers appear to be also affected, with relieving of chronic inflammation and tissue stabilisation. This may be an important and under-appreciated effect, playing a role in the known positive outcomes of NPT, such as better graft-taking rates. [Copyright &y& Elsevier]

Background: Traumatic and iatrogenic injuries of the axillary nerve (AN) are frequent in clinical practice; nevertheless, its anatomy and its relationships with the transdeltoid approaches to the shoulder are not well documented. Materials and methods: Anatomic study was performed on 16 shoulders of unembalmed cadavers. A proximal humeral internal locking system (PHILOS) plate was placed to simulate the osteosynthesis of a fracture of humeral surgical neck. The relationships between the plate and the nerve were evaluated. Selective dissection of all the nerve branches inside the deltoid muscle was performed. Results: The mean distance between the point where the AN entered into the deltoid muscle and the humeral head was 5.0 cm, and it was 6.8 cm from the acromion. The mean distance between the origins of the anterior and posterior branches of the axillary nerve was 5.4 cm. The mean diameter of the AN was 0.57 cm, the anterior branch diameter was 0.40 cm, of posterior branch diameter was 0.33 cm, and the teres minor branch diameter was 0.24 cm. The application of the PHILOS plate demonstrated that in 100% of cases, the 2 distal holes of the plate of those dedicated to the humeral head coincided with the passage of AN. Discussion: The different patterns of nerve branches inside the deltoid muscle show that the “safe zone” during transdeltoid approaches is the anterior region of the deltoid muscle for a maximum of 6.7 cm from the acromion. In addition, the insertion of the 2 distal screws of those dedicated to humeral head of the plate should be avoided. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the macroscopic anatomy and histological characteristics of the transverse carpal ligament and the flexor retinaculum of the wrist and to investigate their anatomical relationships and define appropriate terminology. Methods: The volar regions of the wrists of 30 unembalmed subjects were examined by dissection and by histological and immunohistochemical staining. In vivo magnetic resonance imaging studies were also carried out on 10 subjects. Results: The dissection study showed that the antebrachial fascia at the volar aspect of the wrist presents a reinforcement. From a histological point of view, it is composed of 3 layers of undulated collagen fiber bundles. Adjacent layers show different orientations of the collagen fibers. Many nerve fibers and Pacini and Ruffini corpuscles were found in all specimens. Under this fibrous plane is another fibrous structure, placed transversely between the ulnar-sided hamate and pisiform bones, and the radial-sided scaphoid and trapezium bones. The deeper fibrous structure shows completely different histological characteristics, having parallel, thicker collagen fiber bundles and few nerve fibers. Magnetic resonance images confirm the presence of 2 clearly distinguished fibrous structures in the wrist, the first in continuity with the antebrachial fascia and the second located in a deeper plane between the hamate and scaphoid. Conclusions: Two different fibrous structures with different histological characteristics are present in the volar wrist: the more superficial one is in continuity with the antebrachial fascia and could be considered its reinforcement; the deeper one is composed of strong lamina, with histological features similar to those of a ligament. For these reasons, we suggest that the term transverse carpal ligament should be used to indicate the fibrous lamina connecting the hamate and pisiform to the scaphoid and trapezium and that the term flexor retinaculum of the wrist should be abandoned because it does not correspond to any specific, autonomous structure. [Copyright &y& Elsevier]

Summary: The aim of this study is to analyse the deep fasciae of limbs in order to evaluate the collagen and elastic fibre arrangement and the types of innervation. Histological and immunohistochemical stains were performed in 72 specimens. The deep fascia of the limbs is a sheath presenting a mean thickness of 1mm, formed by two to three layers of parallel collagen fibre bundles. In the adjacent layers, they show different orientations. Each layer is separated from the adjacent one by loose connective tissue, permitting the sliding of the collagen layers. Nerve fibres were found in all specimens, while muscular fibres were evidenced only in one specimen. The described structure permits the fasciae of the limbs to have a strong resistance to traction, even when exercised in different directions. The capacity of the different collagen layers to glide one on the other could be altered in cases of overuse syndrome, trauma, or surgery. [Copyright &y& Elsevier]

Flexor tendon injuries are common and occur mostly by penetrating trauma. Suspected flexor tendon injuries require a thorough clinical assessment and often are not isolated injuries. A detailed understanding of flexor tendon anatomy and spatial relationships is essential, especially when repairing multi-tendon injuries. Principles of flexor tendon repair include a strong suture construct, minimising gap formation between tendon ends, preserving tendon blood supply and providing a smooth repair interface. Moreover, adequate exposure of the zone of injury using full-thickness skin flaps and preservation of neurovascular and pulley structures is essential. In this article an overview of contemporary management strategies is presented. Today's hand surgeons and therapists can choose from a variety of treatment options when managing these important and potentially life-changing injuries. [ABSTRACT FROM AUTHOR]