Earl Z. Browne

Complications of postmastectomy breast reconstructions in smokers, ex-smokers, and nonsmokers

Smoking results in impaired wound healing and poor surgical results. In this retrospective study, we compared outcomes in 155 smokers, 76 ex‐smokers, and 517 nonsmokers who received postmastectomy breast reconstructions during a 10‐year period. Ex‐smokers were defined as those who had quit smoking at least 3 weeks before surgery. Transverse rectus abdominis musculocutaneous (TRAM) flap surgery was performed significantly less often in smokers (24.5 percent) than in ex‐smokers (30.3 percent) or nonsmokers (39.1 percent) (p < 0.001). Tissue expansion followed by implant was performed in 112 smokers (72.3 percent), 50 (65.8 percent) ex‐smokers, and 304 nonsmokers (58.8 percent) (p = 0.002). The overall complication rate in smokers was 39.4 percent, compared with 25 percent in ex‐smokers and 25.9 percent in nonsmokers, which is statistically significant (p = 0.002). Mastectomy flap necrosis developed in 12 smokers (7.7 percent), 2 ex‐smokers (2.6 percent), and 8 nonsmokers (1.5 percent) (p < 0.001). Among patients receiving TRAM flaps, fat necrosis developed in 10 smokers (26.3 percent), 2 ex‐smokers (8.7 percent), and 17 nonsmokers (8.4 percent). Abdominal wall necrosis was more common in smokers (7.9 percent) than in ex‐smokers (4.3 percent) or nonsmokers (1.0 percent). In this large series, tissue expansion was performed more often in smokers than was autogenous reconstruction. Complications were significantly more frequent in smokers. Mastectomy flap necrosis was significantly more frequent in smokers, regardless of the type of reconstruction. Breast reconstruction should be done with caution in smokers. Ex‐smokers had complication rates similar to those of nonsmokers. Smokers undergoing reconstruction should be strongly urged to stop smoking at least 3 weeks before their surgery. (Plast. Reconstr. Surg. 107: 342, 2001.)

Early dynamic splinting for extensor tendon injuries

Extensor tendon injuries are traditionally splinted with no motion for 3 to 4 weeks after repair. This may result in limitation of flexion because of extensor tenodesis at the site of repair. To prevent this, we used a dynamic splinting program opposite to the one that is used for flexor tendon repair, with an outrigger splint holding the fingers in extension and allowing full active flexion. Fifty-two patients who had extensor tendon repairs in the area from the wrist to the middle of the proximal phalanx were treated. Motion was begun 2 to 5 days after repair and was continued for approximately 5 weeks. No tendon ruptures occurred, and all patients recovered full flexion.

Effect of vascular endothelial growth factor (VEGF) on survival of random extension of axial pattern skin flaps in the rat.

Current evidence suggests that neovascularization is mediated by a wide range of angiogenic growth factors. Vascular endothelial growth factor (VEGF) appears to be one of the most important angiogenic factors in vivo. The aim of this project was to evaluate the efficacy of VEGF in augmentation of blood supply to skin flaps. Epigastric skin flaps were raised in 16 Sprague-Dawley male rats. In group A (N = 8), 5 μg of VEGF was injected into the epigastric artery after flap elevation. In the control, group B (N = 8), the artery was injected with saline. On the seventh day, the rats were photographed and the digital images were analyzed using imaging software (Image-Pro Plus 1.2). The blood flow in the flaps was measured with a percutaneous laser Doppler probe at specific locations. Histological studies of the flaps were done. Results showed that the mean percentage surviving flap area was 71.9% in group A and 53.7% in the control group, which is statistically significant (p < 0.001). Histological examination revealed increased density of the capillaries in the flaps treated with VEGF when compared to the control group. We believe the increase in skin survival is due to angiogenesis induced by the VEGF.

Improved perfusion after subcritical ischemia in muscle flaps treated with vascular endothelial growth factor.

Vascular endothelial growth factor (VEGF), a potent endothelial mitogen, is secreted in ischemic tissue and plays a pivotal role in angiogenesis. We studied whether VEGF administered to a rat muscle flap at the time of ischemia induction would increase microcirculatory flow to the flap. The cremaster muscle flap was isolated on its neurovascular pedicle. Ischemia was induced by clamping the vascular pedicle, and 0.2 ml of either VEGF (0.1 microg) or vehicle (phosphate-buffered saline) was immediately infused into the muscle. After 4 or 6 hours, the clamps were released, and the cremaster was placed in a pocket in the medial thigh for 24 hours. The muscle was then dissected, and microcirculatory measurements were made under intravital microscopy. Six animals were used in each of the four groups. All flaps exposed to 6 hours of ischemia, the duration considered to be critical ischemia, had no significant microcirculatory flow, regardless of treatment with VEGF. In the 4-hour ischemia group, or subcritical ischemia group, red blood cell velocity in arterioles was 14 mm/sec in muscles treated with VEGF and 9 mm/sec in controls (p = 0.02), and capillary flow was 7 per high-power field in muscles treated with VEGF versus 2 per high-power field in controls (p = 0.0005). Thus, VEGF did not alter microcirculatory flow in a muscle flap exposed to critical ischemia, but it did enhance flow to a flap exposed to subcritical ischemia.

Ski pole thumb injury.

Disabling injuries can occur in the area of the MP joint of the thumb when a skier falls against the planted ski pole while holding the ski strap in the usual fashion. This is presently the most common ski injury of the upper extremity. It is important to determine if instability has resulted, because there may be disruption of the ulnar aspect of the joint capsule as well as of the extensor-adductor hood mechanism. If this has occurred, it is important to operate upon the patient immediately to prevent the development of the chronic “gamekeepers thumb.”

Conventional versus epineural sleeve neurorrhaphy technique: Functional and histomorphometric analysis

Three methods of nerve repair involving the epineural sleeve technique were compared with conventional nerve repair using the rat sciatic nerve transection model in four groups. In group 1, the sciatic nerve was repaired using the conventional epineural technique by placing four sutures. In groups 2, 3, and 4, the epineural sleeve technique was combined with two sutures, fibrin glue, and two sutures with fibrin glue, respectively. Functional recovery was evaluated using walking track analysis, limb circumference, and the severity of toe contracture. Diameter of the sciatic nerve fibers, total number of myelinated fibers, diameter of the myelin sheath, and the axon-to-fiber diameter ratio were measured at 12 weeks. The results showed better functional recovery as well as a higher number of myelinated fibers in groups using the epineural sleeve technique compared with conventional technique (p < 0.05). The addition of fibrin glue, however, did not make any significant difference. The epineural sleeve technique was found to be superior when compared with conventional nerve repair, providing faster functional recovery and improved nerve regeneration.

Fibrin glue-assisted end-to-side anastomosis of rat femoral vessels : Comparison with conventional suture method

Conventional methods of microvascular anastomosis using sutures cause vessel narrowing, foreign body reactions, and intra-vascular thrombosis. Although fibrin glue seems to be the ideal material to perform a microvascular anastomosis, its success has been limited. Excess fibrin used in some of the earlier methods has caused vessel narrowing and intravascular thrombosis. We evaluated the quality of end-to-side anastomosis using fibrin glue applied with a new technique and minimal sutures, and compared the results to those obtained with a standard suture technique. End-to-side anastomosis of femoral vessels was performed in 32 male Sprague-Dawley rats. Fibrin glue was topically applied at the anastomotic site, after inserting only two corner sutures. The fibrinogen component obtained from single donor human cryoprecipitate, was combined with bovine thrombin (500 IU per milliliter). In the control group (N = 16), the anastomosis was performed using eight to ten interrupted 10/0 nylon sutures. Fibrin glue-assisted anastomosis took less time, caused less bleeding at the anastomotic sites, and achieved a patency rate comparable to that provided by the suture technique. We have shown that a new, atraumatic technique of microvascular anastomosis with cryoprecipitate-thrombin glue and only two sutures, can produce excellent patency rates. This technique is easy to perform, inexpensive, and does not involve new equipment.Padubidri AN, Browne E, Kononov A. Fibrin glue-assisted end-to-side anastomosis of rat femoral vessels: comparison with conventional suture method.

Modification in flap design of the epigastric artery flap in rats : A new experimental flap model

The standard rat epigastric artery flap has been a very reliable model for flap research. The purpose of this study was to describe a modified design of this flap that included only the medial branch of the epigastric artery. Axial-pattern epigastric island skin flaps, measuring 8 × 8 cm, were raised in two groups of Sprague-Dawley male rats. In group A (N = 20) the vascular pedicle consisted of the main trunk of the epigastric vessel and both medial and lateral branches. In group B (N = 20) the flap was based solely on the medial branch of the epigastric artery, excluding the large lateral branch. The flaps were elevated and then sutured back to their beds. Flap survival was studied and the amount of viable skin in both groups was compared 1 week later. The rats were photographed using a digital camera and the images were analyzed using imaging software. The mean percentage surviving flap area in group A was 86.24% and in group B it was 69.72%, which is statistically significant (p < 0.001). We believe that this flap model, with its new modified design that includes a larger flap and inclusion of only the medial branch, will broaden its application to microsurgery. The main advantage of this flap over the conventional epigastric flap is that in this model it is possible to achieve predictable and consistent necrosis in the random extension of the flap.

Epineural sleeve neurorrhaphy: surgical technique and functional results--a preliminary report.

This study was conducted to evaluate the effect of epineural sleeve neurorrhaphy on peripheral nerve regeneration. A total of 12 Lewis rats were divided in two groups of 6 rats each. In group 1, the rat sciatic nerve was transected and repaired using the conventional epineural technique with four sutures. In group 2, the epineural sleeve technique was introduced with two sutures only. Functional recovery was evaluated at 1, 2, 4, 8, and 12 weeks by walking track analysis (sciatic function index [SFI]), mean limb circumference ratio, and severity of toe contracture. Although the SFI at 12 weeks revealed no difference between the two groups (−88.39 ± 10.75 conventional group, −77.35 ± 17.06 epineural sleeve group), significant differences in SFIs were detected at 4 and 8 weeks, with better functional recovery in group 2 rats (4 weeks: 125.92 ± 22.73 conventional group, −99.17 ± 5.45 epineural sleeve group; 8 weeks: −96.65 ± 4.73 conventional group, −72.82 ± 17.11 epineural group;p < 0.05 for both time points). Mean limb circumference ratio was not significant at all time points. At 12 weeks, all animals in the conventional nerve repair group developed severe toe contractures whereas only 2 animals in epineural sleeve repair group had contracture (p < 0.05). In this study, the epineural sleeve technique demonstrated a faster functional recovery when compared with the conventional technique, as confirmed by SFI and toe contracture grading.Siemionow M, Tetik C, Ozer K, Ayhan S, Siemionow K, Browne E. Epineural sleeve neurorrhaphy: surgical technique and functional results—a preliminary report.

The use of muscle flaps for salvage of failed total knee arthroplasty

Deep infections occur in 1-5% of all patients undergoing total knee arthroplasty, and may result in failure of the prosthesis and subsequent arthrodesis. Two-stage reimplantation is often successful, but depends upon the presence of good soft tissue coverage. We have treated 9 patients in whom chronic infection developed which required removal of the prosthesis, debridement, and implantation of antibiotic impregnated spacers for control. These patients all had poor quality soft tissue cover precluding prosthesis reimplantation. The use of muscle flaps resulted in 7 of the 9 patients having successful reimplantation of a prosthesis and remaining free of infection in a follow-up ranging from 1-5 years.