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ABSTRACT: 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.
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.
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.
: 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.
Plastic and reconstructive surgery 03/2012; 129(3):435e-442e. · 2.74 Impact Factor
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Michael W Neumeister
Clinics in plastic surgery 10/2011; 38(4):xiii. · 0.95 Impact Factor
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ABSTRACT: The authors provide a review of treatment of the mutilated hand, discussing the effect of injury on soft tissue loss, intrinsic and extrinsic musculature, paravascular structures, tendons, and the bony skeleton. The authors review functional loss and restoration.
Clinics in plastic surgery 10/2011; 38(4):543-50. · 0.95 Impact Factor
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ABSTRACT: This article discusses scar contracture of the hand. It contains a brief outline of the anatomy of the hand and upper extremities and the types of injuries involved. Hand reconstruction, including examination, nonoperative treatment, surgery, excision and skin grafting, flaps, postoperative management, and complications, are covered.
Clinics in plastic surgery 10/2011; 38(4):591-606. · 0.95 Impact Factor
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ABSTRACT: The hand surgeon's familiarity with options for flexor tendon reconstruction is essential. Efforts at primary repair are not always successful nor are the conditions after injury necessarily conducive to primary coaptation of tendon ends. Single-stage and two-stage grafting, tenolysis, and pulley reconstruction are parts of the reconstructive surgeon's armamentarium. Future interventions of tissue engineering suggest the possibility of creating a theoretically endless supply of available donor material for use in tendon reconstruction.
Clinics in plastic surgery 10/2011; 38(4):607-19. · 0.95 Impact Factor
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ABSTRACT: Ischemia of the hand remains an uncommon condition, but problems with arterial perfusion of the hand can arise from trauma (open and closed), thrombosis, or arteriovascular disease. Certain identifiable patterns are seen with hand ischemia, usually discernable according to which one of the major arteries (radial or ulnar) are involved. This article discusses the origin and management of ischemic hand conditions, with an emphasis on recognizing the patterns of ischemia that are commonly seen.
Clinics in plastic surgery 10/2011; 38(4):739-50. · 0.95 Impact Factor
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ABSTRACT: Traditional management of lateral humeral epicondylitis ("tennis elbow") relies upon antiinflammatory medication, rehabilitation, steroid injection, counterforce splinting, and, finally, surgery to the common extensor origin. The diversity of surgical approaches for lateral humeral epicondylitis (LHE) suggests perhaps that the ideal technique has not been determined. Denervation of the lateral humeral epicondyle is the concept of interrupting the neural pathway that transmits the pain message. Epicondylectomy may accomplish its relief of LHE by denervating the epicondyle.
Since it is known that the posterior branch of the posterior cutaneous nerve of the forearm innervates the lateral humeral epicondyle, 30 patients who were treated surgically for refractory LHE were retrospectively evaluated. Group 1 consisted of 17 patients who were treated with epicondylectomy alone, group II consisted of seven patients who were treated with lateral epicondylectomy plus neurectomy, and group III consisted of seven patients treated with lateral denervation alone.
Denervation alone gave statistically significantly greater improvement in pain relief (p < 0.001) and statistically significantly faster return to work than did epicondylectomy alone (p < 0.001). Denervation plus epicondylectomy gave results that were the same as denervation alone.
It is concluded that denervation gives significant relief from LHE once traditional non-surgical treatment has failed.
Hand 06/2011; 6(2):174-8.
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ABSTRACT: We report a case of targeted muscle reinnervation of a muscle free flap for improved prosthetic control in a patient who had an amputation of the left upper extremity at the level of the shoulder after a severe electrical burn. The reinnervated muscle free flap receives signals from the brachial plexus, and these signals are amplified to provide an interface for a myoelectric prosthesis. This allows for more coordinated and efficient control of the artificial limb.
The Journal of hand surgery 05/2011; 36(5):890-3. · 1.33 Impact Factor
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Michael W Neumeister
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ABSTRACT: Raynaud's phenomenon is a vasospastic disorder of the palmar and digital vessels of the hand and feet that can lead to ischemic ulcers, pain, and loss of function. This study is a review of patients I have injected with botulinum toxin type A for patients with Raynaud's phenomenon.
Raynaud's patients were injected with 50 to 100 units of onabotulinumtoxinA to improve perfusion of the digits. An institutional review board-approved retrospective review was undertaken to analyze outcomes. Laser Doppler scans were performed before and after injection to quantitatively measure perfusion.
A total of 14 men and 19 women with Raynaud's phenomenon were injected with onabotulinumtoxinA. All but 5 patients experienced improved vascularity and relief of pain. Laser Doppler scans illustrated notable improvement in perfusion. Five patients had repeat injections for recurrent pain.
Botulinum toxin appears to improve perfusion of the hand after direct injection around the neurovascular bundles. Further investigations are warranted to identify the exact mode of action in relieving vasospasm and alleviating pain.
The Journal of hand surgery 12/2010; 35(12):2085-92. · 1.33 Impact Factor
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ABSTRACT: Composite tissue allografting may be an ideal solution to many problems requiring reconstructive surgery. Unfortunately, complications associated with chronic immunocompromise are major impediments to widespread use of composite tissue allografting. Current immunosuppressive and immunomodulatory paradigms focus on modification of the recipient through global immunosuppression or donor/recipient chimerism. Alternatively, modifying the allograft to block rejection or promote tolerance could confine deleterious immunosuppressive effects to the graft or eliminate graft rejection. However, a technique introducing genetic information into the transplant is needed. The authors demonstrate the first model for expressing a gene of interest locally in a hind-limb transplant.
Using a rat hind-limb transplant model, the authors tested the ability of naked DNA infusion, cationic polymer/DNA complex transfection, and adenoviral vector transduction to introduce genetic material into the composite tissue allograft. The marker genes luciferase and green fluorescent protein were used to follow gene expression.
Recombinant adenovirus showed rapid, high-level expression of marker genes in the graft, with no detectable expression in recipient animals. Expression was detectable at 18 hours and peaked at 7 days. Levels of expression were lower but above baseline at 4 weeks.
Using an adenoviral vector system, the authors have selectively introduced a marker gene (luciferase) into a transplanted hind-limb rat model. Expression was rapid and seen in a variety of cell types. Adenovirus infection had no impact on limb rejection. This method may be a powerful tool for genetically modifying composite tissue allografts and may contribute to immune tolerance and more widespread use of composite tissue allograft surgery.
Plastic and reconstructive surgery 12/2009; 125(3):837-45. · 2.74 Impact Factor
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ABSTRACT: Treating patients with Raynaud's phenomenon who have chronic pain and ulcerations is extremely challenging. Unrelenting pain can lead to dysfunction and disuse, rendering the patient debilitated and/or chronically depressed. Pharmacologic vasodilators and surgical sympathectomies offer variable benefits. Outcomes of symptomatic patients treated with botulinum toxin type A (Botox) injections for Raynaud's phenomenon are presented.
A retrospective study focused on patient outcomes was performed on 19 patients diagnosed with Raynaud's phenomenon. Patients suffered from chronic ischemic hand pain. All patients had vascular studies to rule out occlusive disease. Fifty to 100 units of Botox were injected into the palm around each involved neurovascular bundle. Preinjection and postinjection laser Doppler scanning was performed on most patients to measure blood flow.
Sixteen of 19 patients (84 percent) reported pain reduction at rest. Thirteen patients reported immediate relief; three reported more gradual pain reduction over 1 to 2 months. Three patients had no or minimal pain relief. Tissue perfusion results demonstrated a marked change in blood flow (-48.15 percent to 425 percent) to the digits. All patients with chronic finger ulcers healed within 60 days. Most patients [n = 12 (63 percent)] remained pain-free (13 to 59 months) with a single-injection schedule. Four patients (21 percent) required repeated injections because of recurrent pain.
Vascular function is abnormal in patients with Raynaud's phenomenon. Although its mechanism is unknown, Botox yielded a distinct improvement in perfusion and reduction in pain in patients failing conservative management. Continued research may lead to more specific and reliable treatment for Raynaud's patients.
Plastic and reconstructive surgery 08/2009; 124(1):191-201. · 2.74 Impact Factor
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Michael W Neumeister
Plastic and reconstructive surgery 08/2008; 122(1):317-8. · 2.74 Impact Factor
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ABSTRACT: The third common digital nerve (TCDN) has been described as the most commonly injured digital nerve during carpal tunnel release (CTR). Anatomic variations of the origin and course of the TCDN from the median nerve may place this structure at risk. Anatomic landmarks may be useful to predict the location of the TCDN to minimize the risk for injury to this structure during CTR.
Twenty cadaveric hands were used to determine the origin and course of the TCDN. The origin of the TCDN from the median nerve was identified in relation to the transverse carpal ligament (TCL), cardinal line, and superficial palmar arch. The course of the TCDN was inspected in relation to the scaphoid tubercle and ring finger.
Three specific anatomic variations for the origin of the TCDN were identified: type 1 originating proximal to the distal edge of the TCL (3 of 20 patients), type 2 originating distal to the TCL but proximal to the superficial palmar arch (14 of 20 patients), and type 3 originating distal to the TCL and at or distal to the superficial palmar arch (3 of 20 patients). The origin of the TCDN was measured as an average of 5.0 +/- 1.2 mm distal to the cardinal line. The TCDN coursed along an oblique vector from the scaphoid tubercle to the midpoint of the palmar digital crease of the ring finger for type 2 or type 3 variations. Near the cardinal line, the oblique course of the TCDN traverses the vector of the longitudinal incision used for CTR.
The TCDN is one of the most frequently damaged neurological structures during CTR. Iatrogenic injury to this structure can be disabling and even devastating to patients. A detailed knowledge of the carpal tunnel and its underlying structures can prevent inadvertent injury to the TCDN. Anatomic landmarks to predict the origin and the course of the TCDN allow the surgeon to preoperatively predict the possible locations and paths of this important structure. This information can prove to be useful in avoiding injury to the TCDN by clinicians performing CTR in their practice, whether via the open or via endoscopic technique.
Eplasty 02/2008; 8:e51.
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Plastic and reconstructive surgery 11/2007; 120(5):1322-5. · 2.74 Impact Factor
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ABSTRACT: This article explores issues related to tissue engineering and composite tissue allografts that employ physiologic and anatomic autogenous replicates to restore tissue loss. Composite tissue allotransplantation has become a controversial option for reconstruction, most prominently for reconstruction involving the hand and, recently, the face. While the side-effect profile of systemic immunosuppression continues to improve, the long-term risks of immunosuppression leaves composite tissue allotransplantation a domain for cautious exploration. Meanwhile, tissue engineering could, conceivably, be the gap between replantation and composite tissue allografts. Whereas the perils of immunosuppression may limit the routine use of allografts, employing constructions made of the patient's own cells negates the need for any antirejection therapy.
Clinics in Plastic Surgery 05/2007; 34(2):319-25, xi. · 1.42 Impact Factor
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ABSTRACT: Replantation aims to restore the amputated part to its anatomical site, preserving function and appearance. Outcome depends on factors intrinsic to the patient and to the nature of the injury. Young patients who have distal, cleanly amputated extremities have the best return of function; multiple levels of injury, crush, or avulsing injuries have less. Patients must be fully informed about the commitment to rehabilitation and the possibility of multiple surgeries needed for best results. Similarly, patient and surgeon expectations should be evaluated and addressed before replantation. Meticulous microsurgical technique, comprehensive occupational therapy, and perseverance are needed for success. Addressing these issues promotes a team rehabilitation to restore function while getting the amputation patient back to productive position in society.
Clinics in Plastic Surgery 05/2007; 34(2):177-85, vii-viii. · 1.42 Impact Factor
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ABSTRACT: After a severe digital or extremity injury, the replantation surgeon should always seek to make the best use out of what tissue is available for reconstruction. Exercising sound surgical judgment and being creative allow the surgeon to restore function to critical areas of the hand or extremity by the judicious use of available tissues that would otherwise be discarded. The use of "spare parts" should, therefore, always be considered to facilitate digital or extremity reconstruction when routine replantation is not possible or is likely to produce a poor functional result. The surgeon should always try to use available nonreplantable tissue to preserve length, obtain soft tissue coverage, or most importantly improve the function of remaining less injured digits. This article presents several case studies that illustrate the principals of spare parts reconstruction performed at the time of the initial debridement using nonreplantable tissue to provide coverage or improve function.
Clinics in Plastic Surgery 05/2007; 34(2):211-22, viii. · 1.42 Impact Factor
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Michael W Neumeister
Hand 04/2007; 2(1):25-6.
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ABSTRACT: A paucity of appropriate regional and local matching tissue can compromise the reconstruction efforts in areas of the body that require specialized tissue. The current study uses techniques of vascular prefabrication, tissue culturing, and capsule formation to form a vascularized ear construct that is reliably transferable on its blood supply.
Thirty male Wistar rats (250 to 350 g) were anaesthetized. An incision was made over the right lower abdominal wall. A pocket was formed by blunt dissection just below the panniculus carnosus. A separate incision was made over the right femoral vessels, which were then isolated and transected distally. The vessels were transposed in a subcutaneous plane to the abdominal wound. A silicone mold in the shape of an ear (2 x 1.5 cm) was placed over the transposed vessels in the abdominal wound pocket. The wounds were closed. Auricular cartilage was minced, washed, and cultured. After 14 days, the chondrocyte culturing was complete and a vascularized capsule based on the incorporated, transposed femoral vessels was formed. The abdominal incision was then reopened, an incision was made in the lateral capsule, and the cultured chondrocytes were introduced into the molded capsule. Study groups included capsules filled with chondrocytes only, chondrocytes and a fibrin glue carrier, and the fibrin glue only. The capsule was closed and the wounds sutured. The prefabricated, prelaminated construct was isolated on its vascular pedicle 14 days later and traversed microsurgically to the contralateral leg vessels. Histologic analysis was performed.
All 30 capsules were completely vascularized and could be reliably isolated and transferred microsurgically on the transposed femoral vessels. The pedicle, being incorporated directly into the capsule, provided the dominant blood supply to the construct. None of the capsules with the fibrin glue only retained any shape and all were devoid of cartilage. Similarly, there was no evidence of retained cartilage in the capsules filled with chondrocytes alone. All capsules with the chondrocytes and the fibrin carrier had mature shaped cartilage preserved. External molds were required to maintain the shape of the ear. Extrusion, although almost uniform in the group with external molds, did not interfere with the end construct shape or vascularity. When molds were used, four of six had excellent maintenances of shape and two of six had only minor superior pole deformation. All constructs were reliably transferred as free flaps.
The authors have shown that transposing a vascular pedicle to a subcutaneously placed silicone block will result in a vascular capsule that can be mobilized and transferred based solely on the pedicle. Although the capsule provides vascularity to the chondrocytes, the cultured cartilage will fill the shape of the silicone mold only if an appropriate carrier such as fibrin glue is used and an external mold is applied.
Plastic and reconstructive surgery 02/2006; 117(1):116-22. · 2.74 Impact Factor
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ABSTRACT: The pincer-nail deformity is characterized by an excessively curved and distorted nail across the transverse dimension. Forty-nine sides (paronychial folds) were dissected off the distal phalanx periosteum with scissors and/or a small elevator. The dermis was placed between the paronychial fold and the plalanx to flatten the germinal and sterile matrix. Direct comparison of autograft dermis to homograft dermis did not show any significant differences in postcorrection appearance of the nail or relief of symptoms. Surgical time averaged 22 minutes less in those patients having reconstruction on both sides of one nail with homograft dermis.
The Journal Of Hand Surgery 04/2005; 30(2):400-3. · 1.35 Impact Factor
