Shyh-Jou Shieh

Free anterolateral thigh flap for reconstruction of head and neck defects following cancer ablation

Thirty-seven consecutive free anterolateral thigh flaps in 36 patients were transferred for reconstruction of head and neck defects following cancer ablation between January of 1997 and June of 1998. The success rate was 97 percent (36 of 37), with one flap lost due to a twisted perforator. The anatomic variations and length of the vascular pedicle were investigated to obtain better knowledge of anatomy and to avoid several surgical pitfalls when it is used for head and neck reconstruction. The cutaneous perforators were always found and presented as musculocutaneous or septocutaneous perforators in this series of 37 anterolateral thigh flaps. They were classified into four types according to the perforator derivation and the direction in which it traversed the vastus lateralis muscle. In type I, vertical musculocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 56.8 percent of cases (21 of 37), and they were 4.83 ± 2.04 cm in length. In type II, horizontal musculocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 27.0 percent of cases (10 of 37), and they were 6.77 ± 3.48 cm in length. In type III, vertical septocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 10.8 percent of cases (4 of 37), and they were 3.60 ± 1.47 cm in length. In type IV, horizontal septocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 5.4 percent of cases (2 of 37). They were 7.75 ± 1.06 cm in length. The average length of vascular pedicle was 12.01 ± 1.50 cm, and the arterial diameter was around 2.0 to 2.5 mm; two accompanying veins varied from 1.8 to 3.0 mm and were suitable for anastomosis with the neck vessels. Reconstruction of one-layer defect, external skin or intraoral lining, was carried out in 18 cases, through-and-through defect in 17 cases, and composite mandibular defect in two cases. With increasing knowledge of anatomy and refinements of surgical technique, the anterolateral thigh flap can be harvested safely to reconstruct complicated defects of head and neck following cancer ablation with only minimal donor-site morbidity.

Distally based anterolateral thigh flap: an anatomic and clinical study.

The distally based anterolateral thigh flap has been used for coverage of soft-tissue defects of the knee and upper third of the leg. This flap is based on the septocutaneous or musculocutaneous perforators derived from the lateral circumflex femoral system. The purpose of this study was to examine the results of anatomical variations of the descending branch of the lateral circumflex femoral artery and the retrograde blood pressure of the descending branch of the lateral circumflex femoral artery so that the surgical technique for raising and transferring a distally based anterolateral thigh flap to the knee region could be improved. The authors have actually used this flap in three cases. In 11 thighs of six cadavers, the descending branch of the lateral circumflex femoral artery had a rather consistent connection with the lateral superior genicular artery or profunda femoral artery in the knee region. The pivot point, located at the distal portion of the vastus lateralis muscle, ranges from 3 to 10 cm above the knee. In their three cases, the maximal flap size was 7.0 × 16.0 cm and was harvested safely, without marginal necrosis. The mean pedicle length was 15.2 ± 0.7 cm (range, 14.5 to 16 cm). The average proximal and distal retrograde blood pressure of the descending branch of the lateral circumflex femoral artery was also studied in another 11 patients, and the anterolateral thigh flap being used for reconstruction of head and neck defects showed 58.3 and 77.7 percent of proximal antegrade blood pressure, respectively. The advantages of this flap include a long pedicle length, a sufficient tissue supply, possible combination with fascia lata for tendon reconstruction, and favorable donor-site selection, without sacrifice of major vessels or muscles.

Anatomical variability of the anterolateral thigh flap perforators: vascular anatomy and its clinical implications.

Background: Anatomical variability of perforators of the anterolateral thigh flap has been reported. The authors introduce a classification based on the number, location, and origin of the cutaneous perforators to comprehensively illustrate their vascular patterns in hopes that unfavorable anatomical variations of the anterolateral thigh flap can be overcome in clinical applications. Methods: The authors enrolled and reviewed 110 anterolateral thigh flaps created between September of 2010 and January of 2013 for head and neck reconstruction after cancer ablation. The location of the perforators was defined by Yus ABC system. Its corresponding origin from the descending or transverse branch of the lateral circumflex femoral artery was clarified by Shiehs vascular anatomical classification for the anterolateral thigh flap. Results: Of the 110 flaps, a single perforator (A or B or C) was observed in 20 flaps (18.2 percent), double perforators (A + B or B + C or A + C) were observed in 59 flaps (53.6 percent), and triple perforators (A + B + C) in 31 flaps (28.2 percent). The origin of perforators was the descending branch in 76 flaps (69.1 percent), the transverse branch in 10 flaps (9.1 percent), and both descending and transverse branches in 24 flaps (21.8 percent). The authors observed 16 vascular patterns. The most common type was double perforators, with perforators B and C originating from the descending branch [n = 40 (36.4 percent)]. Conclusions: The clinical significance of each pattern is delineated, and surgical technical considerations are suggested according to flap requirements and types of vascular anatomy.

Angiogenin expression in burn blister fluid: Implications for its role in burn wound neovascularization

Deep partial thickness burn (DPTB) wound fluids have a greater propensity for establishing neovascularization than did superficial partial thickness burn (SPTB) wound fluids in our previous study. To investigate the factors responsible for this activity, cytokine array and enzyme‐linked immunosorbent assay were used to perform an expression analysis of angiogenic factors in burn fluid. Although present in approximately equal amounts in both SPTB and DPTB blister fluids from burn patients, angiogenin does appear to be involved in the ability of DPTB blister fluid to promote neovascularization in vitro and in vivo. Angiogenin alone was sufficient to induce endothelial differentiation of circulating angiogenic cells (CAC) without vascular endothelial growth factor A involvement. In addition, angiogenin was positively associated with CAC differentiation in the burn blister fluid. Blocking the effect of angiogenin in burn blister fluids resulted in a significant reduction of endothelial cell proliferation, CAC differentiation, and new blood vessels formation in vivo. Moreover, immunohistochemistry revealed that high angiogenin expression colocalizes with high vascularity in human burn wounds at day 7, further supporting our hypothesis that angiogenin is involved in burn wound neovascularization.

Deep partial thickness burn blister fluid promotes neovascularization in the early stage of burn wound healing

The effect of burn blister fluid in neovascularization during burn wound healing is unknown. Burn blister fluid, containing a large amount of chemokines, is thought to play a role in the early stage of neovascularization. This process includes angiogenesis and vasculogenesis. Because of different healing time of burn wounds, we hypothesized that neovascularization in superficial partial thickness burn (SPTB) and deep partial thickness burn (DPTB) wounds were different. The neovasculogenic effects of two different burn blister fluids were also different. We found Day 7 DPTB wounds had a significant increase in blood vessels compared with SPTB wounds by immunohistochemistry. DPTB blister fluid significantly promoted neovascularization via increasing endothelial cell proliferation, and migration and differentiation of circulating angiogenic cells relative to SPTB blister fluids. In the animal study, DPTB blister fluids markedly promoted new blood vessel formation compared with those from SPTB blister fluids using in vivo Matrigel plug assay. These results suggest that DPTB wounds require more new vessel formation than SPTB. Furthermore, the measurement of angiogenic activities in burn blister fluids serves as a possible tool for assessing burn wound status.

Secondary procedures following digital replantation and revascularisation

In this retrospective study, 79 digits of 55 patients received 102 secondary procedures following replantation. We divided the procedures into two groups, occurring before or after 2 months following replantation. The procedures in the early group were mainly for soft tissue coverage (92%), and those in that late group were mainly for tendon (67%) to improve function. Factors associated with higher incidence of early secondary procedures included multiple-finger injury, avulsion or degloving injury and level of injury proximal to zone III in finger replantation (p<0.05). However, younger patients and those with proximal level replantation in fingers had more late secondary procedures (p<0.05). Flexor tenolysis procedure significantly improved the digital function after replantation (p<0.05).

Regeneration and repair of human digits and limbs: fact and fiction

Abstract A variety of digit and limb repair and reconstruction methods have been used in different clinical settings, but regeneration remains an item on every plastic surgeons “wish list.” Although surgical salvage techniques are continually being improved, unreplantable digits and limbs are still abundant. We comprehensively review the structural and functional salvage methods in clinical practice, from the peeling injuries of small distal fingertips to multisegmented amputated limbs, and the developmental and tissue engineering approaches for regenerating human digits and limbs in the laboratory. Although surgical techniques have forged ahead, there are still situations in which digits and limbs are unreplantable. Advances in the field are delineated, and the regeneration processes of salamander limbs, lizard tails, and mouse digits and each component of tissue engineering approaches for digit‐ and limb‐building are discussed. Although the current technology is promising, there are many challenges in human digit and limb regeneration. We hope this review inspires research on the critical gap between clinical and basic science, and leads to more sophisticated digit and limb loss rescue and regeneration innovations.

Glomus tumor twenty-year experience and literature review

AbstractGlomus tumors are rare, usually benign, vascular hamartomas consisting cells resembling the smooth muscle cells of the normal glomus body. They can be solitary or multiple, whereas solitary tumors are majorly located on the digits. Digital glomus tumors most commonly appear in subungual region and show a strong female predominance. There are several classical symptoms, clinical tests, and imaging tools, such as X-ray, magnetic resonance imaging, and ultrasonography, which can provide good accuracy for clinical diagnosis. However, misdiagnosis and delayed diagnosis are still commonly observed because primary physicians are unfamiliar with classical symptoms and clinical tests. Complete surgical excision often can result in complete relief of symptoms. Recurrence is largely caused by incomplete excision, but repeated image study is recommended to rule out new or malignant lesions. This series is a retrospective review of 50 cases with glomus tumors managed at our institute. We aim to review the key aspects of glomus tumor and provide a simple guideline for earlier diagnosis and treatment.

Correlation of digital sensibility and precision of pinch force modulation in patients with nerve repair

The outcome measures for patients following peripheral nerve repairs commonly include muscle strength and sensory assessments. However, no significant discussion exists on the impact of nerve injury on sensorimotor control. The objective of this longitudinal study was to explore the effects of nerve regeneration on the control of pinch force in executing functional tasks. Seven patients with digital or median nerve repairs were assessed by a custom‐designed pinch device and conventional sensory tools at monthly intervals following nerve repair. These tools measured sensibility, maximum pinch strength, and anticipated pinch force adjustments to movement‐induced load fluctuations in a pinch‐holding‐up activity (PHUA). Six force‐related and temporal parameters for sensory measurement were used to determine improvements in pinch performance over time following sensory recovery. The results revealed significant differences in the parameters of peak pinch force, baseline pinch force, force ratio, and the percentage of maximal pinch force output at different points in the course of nerve regeneration. A strong relationship was also found between kinetic data from the PHUA test and the traditional sensibility tests for the nerve repair patients in the present study.

Reconstruction of a massive femoral bone defect using a double-barreled free vascularized fibular bone graft after wide resection of femoral chondrosarcoma.

Salvaging the limb after malignant bone tumor ablation is a tough challenge for a reconstructive surgeon confronting such extensive bone defects. A 40‐year‐old male without any underlying disease was incidentally diagnosed with a chondrosarcoma over his left femoral bone. An orthopedic surgeon did a wide resection of the malignant bone tumor, leaving a massive bone defect about 11.3 cm in length. A double‐barreled free vascularized fibular bone was designed to reconstruct the femoral bone defect. The maximal fibular bone graft harvested was 19 cm long; after the osteotomy, one barrel was 11 cm and the other was 8 cm. An iliac crest cancellous bone graft was harvested to fill the residual space. The pathology report showed a grade 1 well‐differentiated conventional chondrosarcoma, and further adjuvant therapy was not suggested. At a 3‐year follow‐up, plain radiography showed a good bony union of the graft, and the patient could easily tolerate daily activity. A vascularized double‐barreled fibular graft is an ideal option for reconstructing a massive defect in weight‐bearing bone: it provides not only sufficient mechanical strength but also good union for early rehabilitation. We describe the long‐term results after reconstruction and provide a literature review of long‐bone chondrosarcoma.