Reuben A. Bueno

Safe Treatment of Trigger Finger with Longitudinal and Transverse Landmarks: An Anatomic Study of the Border Fingers for Percutaneous Release

Transverse landmarks have recently been determined to predict the proximal and distal edges of the A1 pulley for trigger finger release. Percutaneous A1 pulley release has been discouraged for the border digits because of the risk of injury to the neurovascular structures of the index and small fingers. The purpose of the study was to identify longitudinal surface landmarks to prevent injury to the neurovascular bundles during percutaneous A1 pulley release of the ulnar and radial border digits. Longitudinal surface landmarks were identified and marked on 29 cadaver hands. Proximal and distal landmarks for the longitudinal vector through which the A1 pulley of the small finger was released include the midline of the proximal digital crease and the scaphoid tubercle. Proximal and distal landmarks for the longitudinal line through which the index finger A1 pulley was released include the midline of proximal digital crease and radial edge of the pisiform. Longitudinal incisions were performed between these landmarks, straight through the skin and deep enough to score the A1 pulley. The distance of the medial edge of the neurovascular structures from the longitudinal incision in the A1 pulley was measured for each small finger and index finger. Using these longitudinal landmarks for the index and small fingers, none of the neurovascular structures was injured while performing these longitudinal incisions through the skin, scoring the A1 pulley. In fact, the average distance for the neurovascular structures from the longitudinal vector of the small finger was 5.4 ± 1.4 mm radially and 6.7 ± 1.9 mm ulnarly. The average distance for the neurovascular structures from the longitudinal line of the index finger was 8.5 ± 1.8 mm radially and 6.2 ± 1.7 mm ulnarly. Based on the findings of this anatomical study, these longitudinal landmarks can be used to avoid injury to neurovascular structures in the management of trigger finger involving the border digits with steroid-injection, open, or percutaneous A1 pulley release.

LOSS OF SILICONE IMPLANTS AFTER SUBCUTANEOUS MASTECTOMY AND RECONSTRUCTION

We studied 89 patients who had immediate or delayed placement of implants after subcutaneous mastectomies. The complications of infection, necrosis of the skin or areola, and extrusion of the prosthesis occurred in 28 percent of these patients, and the incidence was the same after immediate or delayed placement. Only one of the 45 patients who received prophylactic antibodies preoperatively developed an infection after insertion of the prosthesis. The late complications in some of these patients indicate the need for long-term follow-up.

Innovations in prosthetic interfaces for the upper extremity.

Summary: Advancements in modern robotic technology have led to the development of highly sophisticated upper extremity prosthetic limbs. High-fidelity volitional control of these devices is dependent on the critical interface between the patient and the mechanical prosthesis. Recent innovations in prosthetic interfaces have focused on several control strategies. Targeted muscle reinnervation is currently the most immediately applicable prosthetic control strategy and is particularly indicated in proximal upper extremity amputations. Investigation into various brain interfaces has allowed acquisition of neuroelectric signals directly or indirectly from the central nervous system for prosthetic control. Peripheral nerve interfaces permit signal transduction from both motor and sensory nerves with a higher degree of selectivity. This article reviews the current developments in each of these interface systems and discusses the potential of these approaches to facilitate motor control and sensory feedback in upper extremity neuroprosthetic devices.

Skills coaches as part of the educational team: A randomized controlled trial of teaching of a basic surgical skill in the laboratory setting

BACKGROUND The aim of this study was to compare the laboratory teaching of a basic technical skill by a nonphysician skills coach and a faculty surgeon. METHODS Medical students were randomized to instruction of skin suturing in the skills laboratory by a faculty surgeon or by a nonphysician skills coach. Testing of performance occurred at 3 time points. Other faculty surgeons, blinded to identities and training groups, rated performance. RESULTS Forty-nine students participated. Baseline fourth-year student mean scores showed no significant difference between training groups. Third-year and fourth-year student performance showed no difference between training groups on postintervention testing. Delayed testing also showed no difference in third-year student scores. CONCLUSIONS Training by either a nonsurgeon skills coach or a faculty surgeon resulted in no difference in performance on a basic surgical skill. This was true for students with and without prior experience and was also true after subsequent clinical experiences. Nonphysician coaches may ease the teaching burden of surgical faculty members while providing similar quality of instruction for trainees.

Subungual melanoma: a review of current treatment.

Background: Subungual melanoma typically presents as a darkened longitudinal stripe under the nail plate; however, this disease is frequently misdiagnosed, which leads to a delay in proper diagnosis. Subsequently, subungual melanoma historically has a relatively poor prognosis compared with other cutaneous melanomas, with the 5-year survival rate ranging between 16 and 80 percent. Historically, these lesions were removed using aggressive amputation. To date, the National Cancer Institute does not have guidelines for the treatment of subungual melanoma. Methods: The authors conducted a complete review of all cases within the literature involving amputation and/or wide local excision for the treatment of subungual melanoma. Results: There is currently a trend toward a more conservative approach in treating subungual melanoma; however, the literature does not offer a high level of evidence, and definitive conclusions cannot be drawn. Conclusions: Overall, the studies within the literature involving amputation as the treatment for subungual melanoma could not prove a significant benefit, in terms of prognosis and/or survival, over the more conservative treatment of excision. The collective data imply that melanoma in situ can likely be treated appropriately with wide local excision. The literature lacks randomized, prospective, or comparative studies that would help elucidate whether amputation is superior to a more conservative, digit-sparing approach. Prospective randomized control trials are indicated.

Adipose-derived stem cell to epithelial stem cell transdifferentiation: a mechanism to potentially improve understanding of fat grafting's impact on skin rejuvenation.

BACKGROUND Recent evidence suggests that lipofilling improves overlying skin composition and appearance. Adipose-derived stem cells (ADSC) have been implicated. OBJECTIVE The authors identify ADSC transdifferentiation into epithelial stem cells through coexpression of GFP+ (green fluorescent protein positive) ADSC with the epithelial stem cell marker p63 in an in vivo fat grafting model. METHODS Six male, GFP+ mice served as adipose tissue donors. Twelve nude mice served as recipients. Recipients were subdivided into 2 arms (6 mice/each arm) and received either whole-fat specimen (group 1) or isolated and purified ADSC + peptide hydrogel carrier (group 2) engrafted into a 1-cm(2) left parascapular subdermal plane. The right parascapular subdermal plane served as control. Skin flaps were harvested at 8 weeks and subjected to (1) confocal fluorescent microscopy and (2) reverse transcriptase polymerase chain reaction (RT-PCR) for p63 mRNA expression levels. RESULTS Gross examination of skin flaps demonstrated subjectively increased dermal vessel presence surrounding whole-fat and ADSC specimens. The GFP+ cells were seen within overlying dermal architecture after engraftment and were found to coexpress p63. Significantly increased levels of p63 expression were found in the ADSC + hydrogel skin flaps. CONCLUSIONS We offer suggestive evidence that GFP+ ADSC are found within the dermis 8 weeks after engraftment and coexpress the epithelial stem cell marker p63, indicating that ADSC may transdifferentiate into epithelial stem cells after fat grafting. These findings complement current understanding of how fat grafts may rejuvenate overlying skin.

Aggressive digital papillary adenocarcinoma presenting as finger infection.

Aggressive digital papillary adenocarcinoma (ADPA) is a rare tumor of sweat gland origin that may present in a nonspecific manner on the finger. The authors report a case of ADPA that was treated initially as a chronic infection of the finger, leading to a delay in diagnosis and definitive treatment. Failure of the wound to heal led to a biopsy of the lesion, which revealed ADPA. Because of the potential for aggressive local growth and distant metastases, amputation was indicated. This case demonstrates the importance of considering ADPA in the differential diagnosis of nonhealing wounds of the finger that have not responded to other forms of treatment. Wide local excision with clear margins and close surveillance for signs of recurrence or metastasis are indicated for this rare sweat gland neoplasm.

Hand tumors: II. Benign and malignant bone tumors of the hand.

Summary: The incidence of both benign and malignant bone tumors arising in the hand is relatively low in comparison with other locations. Although the overwhelming majority of these tumors are benign, even benign tumors can be locally destructive and compromise hand function. Intralesional tumor excision is the most appropriate surgical intervention for many benign bone tumors of the hand; however, destructive or malignant tumors may require wide local excision or even amputation to achieve complete tumor eradication. The purpose of this review article is to provide an overview of the pertinent benign and malignant bone tumors that may be encountered by hand surgeons. Clinical presentation, radiographic features, recommended workup, and available treatment options are all reviewed.

Hand tumors: I. skin and soft-tissue tumors of the hand.

Summary: Hand tumors of the skin and soft tissue are frequently encountered by plastic surgeons. Although similar to lesions affecting other parts of the body, the presentation, workup, and treatment options often differ in the hand secondary to its complex anatomy and functional significance. The purpose of this article is to provide an overview of those lesions that commonly arise in the hand—including epidermal inclusion cysts, ganglion cysts, and glomus tumors—in addition to tumors such as soft-tissue sarcomas that are rare but nonetheless require astute diagnosis and expedient initiation of treatment. Presenting symptoms and clinical features, recommended workup, and appropriate treatment options are reviewed.

Early growth response factor-1: expression in a rabbit flexor tendon scar model.

Background: Adhesion formation limits functional recovery after flexor tendon repair. Various growth factors have been implicated in the adhesion scar process. Early growth response factor-1 (EGR-1), a transcription factor associated with synthesis of a variety of key fibrotic growth factors and expression of extracellular matrix genes, has never been identified in a tendon repair model. Methods: Thirty New Zealand White rabbit forepaws underwent laceration and repair of the middle digit flexor digitorum profundus equivalent in zone II. Sodium morrhuate, a topical sclerosing agent, or phosphate-buffered saline, a standard control, was applied to the repair during closure of the tendon sheath. Tendons were harvested from operated and unoperated forepaws at increasing time intervals (1, 3, 7, 14, and 28 days). Tissues were analyzed by immunohistochemistry and Masson trichrome staining. Results: Immunohistochemistry demonstrated that EGR-1 is expressed at the site of tendon repair, along the epitenon of the tendon, and in the infiltrate of inflammatory cells in the surrounding sheath-scar matrix. Control, unoperated tendons demonstrated baseline EGR-1 expression within epitenon cells. EGR-1 was maximally expressed on postoperative day 7. Sodium morrhuate and phosphate-buffered saline demonstrated no difference in their ability to augment tendon adhesion scar formation. Conclusions: Findings demonstrate the following: (1) EGR-1 expression is increased in the tendon wound environment after flexor tendon laceration repair; (2) normal epitenon cells have low, baseline levels of EGR-1 expression; and (3) sodium morrhuate does not augment scar matrix production more than phosphate-buffered saline. The ideal tendon scar model was not generated.