Tendinous cutaneous dorsal hand injuries. One-stage reconstruction

The reconstruction of complex cutaneous tendinous dorsal hand injuries represents a problem that is not easy to solve. The transferral in a single surgical stage, with a single flap, of skin, tendons, and nerves, all completely vascularized, is probably the ideal solution. Between 1988 and 1999 the one-stage reconstruction method was used in 13 patients. A cutaneous tendinous dorsalis pedis free flap was used in 7 cases, and a cutaneous tendinous radial forearm island flap with an inverted flow was used in 6. The dorsalis pedis flap allows for the inclusion of 4 tendons that are completely vascularized (extensor digitorum communis), while the radial flap allows us to completely insert a single tendon (palmaris brevis) and two vascularized tendinous strips taken from the flexor carpi radialis and from the brachioradialis. All of the flaps transferred survived perfectly with good functional recovery. One-stage reconstruction that is "completely vascularized" allows us to reduce the amount of time spent in hospital, the number of operations, and above all it provides cosmetic and functional results that are close to normal. The dorsalis pedis flap is indicated in cases of cutaneous tendinous dorsal hand injuries that require the simultaneous reconstruction of three or four extensor tendons. On the other hand, the radial flap may be used in situations where it is necessary to reconstruct only 1 or 2 tendons.

Neovascularized bone grafts: experimental investigation

Vascularized bone grafts are standardized procedures in reconstructive surgery but there are some disadvantages: donor site morbidity, limited number of "natural" donor sites, and complex technique. In this study, we test the possibility of creating a "neovascularized" bone graft utilizing a vascular implantation procedure in a rabbit model. Sixteen New Zealand adult white rabbits were used. In each animal, two iliac crest bone grafts (7 x 7 x 10 mm) were harvested. Vascular implantation of the right superficial femoral vessels was performed in one of the two grafts, which was wrapped in a silicone envelope to avoid neovascularization from the surrounding tissues and positioned in a subcutaneous pocket in the right medial thigh. On the left side, the bone block, wrapped in the silicone envelope, was buried subcutaneously without vascular implantation. The operated animals were divided into two groups: Group I included eight rabbits explanted 4 weeks postoperatively and Group II included eight rabbits explanted 8 weeks postoperatively. Tetracycline injection was performed 72 hours preexplantation to evaluate new bone formation. Selective colloidal ink injection in the axial artery was performed to investigate the neovascularization before inclusion in poly-methyl-methacrylate (PMMA). Histological examination was performed in all explanted specimens comparatively. Histological examination 8 weeks after surgery showed a marked neovascularization, with normal bone cells. Tetracycline labeling showed new bone formation with a normal pattern. In all nonvascularized specimens, no viable cells or neovascularization and no bone formation were found. The vascular implantation procedure can induce a good neovascularization with new bone formation in a small bone graft. The possibility of neovascularization induction by the simple vascular implantation procedure has several clinical implications in reconstructive surgery.

Distal thumb reconstruction using a mini wrap-around flap from the great toe

We have used a great toe mini wrap-around flap for reconstruction of the thumb at, or distal to, the interphalangeal joint. Our series included 12 patients with traumatic amputations. A flap including the entire nail and most of the distal phalanx of the great toe was used. Eleven of the grafts survived. Sensibility was good with an average of 10 mm static two-point discrimination (range, 5-15) and there were no complaints of cold intolerance. All patients were pleased with the appearance of the thumb and there was no significant morbidity at the great toe donor site. The great toe mini wrap-around flap is an excellent reconstruction technique for selected patients with distal thumb amputations.

Replantation of degloved skin of the hand

The treatment of a degloving injury is one of the most difficult problems in hand surgery. Various reconstructive procedures have been adopted in the past years, all with poor results. Between 1988 and 1995, nine patients with degloving injuries of the hand and fingers were treated by microsurgical replantation. The injury involved the thumb in three patients, the ring finger in three patients, the little finger in one patient, and multiple fingers in two patients. Successful complete revascularization was obtained in seven patients. In one case a superficial necrosis of the replanted thumb skin occurred with good preservation of the subcutaneous layer. In one patient with a degloving injury involving multiple fingers, revascularization was achieved only in the middle finger, and the first ray was secondarily resurfaced by a free flap from the foot. In our experience revascularization of the degloved skin does represent the best solution and must be managed as an emergency procedure. Coverage obtained in this way offers the best cosmetic result and allows early mobilization with good recovery of joint movement. Reestablishing sensibility is more difficult. It is not always possible to suture the nerves damaged by the trauma, and even when a careful primary nerve anastomosis is performed, the results often are unsatisfactory, probably because of the avulsive mechanism of nerve injury.

Homodigital neurovascular island flaps with "direct flow" vascularization

Pulp loss of the fingers is frequently observed. When local advancement flaps are not sufficient to repair the defect, the homodigital monopedicled island flaps with "direct flow" are a simple and current reconstructive solution. Between 1991 and 1995, 32 homodigital neurovascular direct flow island flaps were performed for fingertip defects. We used a modified triangular Venkataswami flap for oblique amputations (26 patients) and the Mouchet-Gilbert island flap for tangential defects (6 patients). Our results (with excellent skin quality and good sensory recovery) lead us to consider these flaps as the first-choice reconstructive solution in patients with extensive but not complete pulp defects (< 2 cm) of the fingers.

Ring avulsion injuries: microsurgical management

Microsurgical treatment of ring avulsion injuries is often difficult, due to widespread intimal damage of the digital vascular bundles. Thirty-one patients with such injuries in varying degrees were treated during the period 1986 to 1992: of these, 15 underwent microsurgical revascularization. In addition to the traditional procedures applied in seven patients (arteriolysis, direct vessel suture, vein grafts), a technique consisting of vessel transfer from the middle finger was also employed. In five patients, the ulnar digital artery of the middle finger was transferred to the ring finger. In four patients, at least one vein was transferred from the dorsal aspect of the middle finger. Twelve of 15 microreconstructions were successful: with an average follow-up of 48.3 months, these patients showed very good functional (mean total active range of motion: 234 degrees and mean s2PD: 9.8mm) and cosmetic recovery. These results lead to the conclusion that, except for cases characterized by proximal amputation at the flexor superficialis tendon insertion, microsurgical treatment should always be carried out.

Transfer of vessels in the management of thumb and ring avulsion injuries

The main problem in avulsion or degloving injury is the extensive damage to long segments of vessels which makes direct suture of the structures difficult. Various techniques have been proposed over the years to bypass the segment of an injured vessel. Many of these are difficult and often require the execution of several vascular anastomoses. The transfer of vessels from adjacent fingers, as proposed by Doi, is a valid alternative. During the 5-year period from 1988 to 1993, vessel transfer from adjacent fingers was carried out on 15 patients. Three patients suffered incomplete amputation and 5 patients suffered complete amputation of the thumb. In 5 cases these were severe crush injuries and in 3 cases they were avulsion injuries. Seven patients suffered ring avulsion injuries of various degrees. The simplicity and reliability of the method (one case was unsuccessful) make this an important technique in the treatment of crush and avulsion injuries of the thumb as well as of ring avulsion injuries.

Degloving injuries of the hand and fingers

Wound coverage after a complete degloving injury of the hand and fingers is 1 of the most difficult problems in hand surgery. Important structures such as tendons, nerves, and bones are exposed and will necrose if not covered adequately. The goal of treatment should be coverage with a pliable, sensitive, and cosmetically similar tissue that will allow early mobilization. The authors' experience has led them to adopt the following general guidelines: replantation of the avulsed structures whenever possible; early transfer of a free composite flap from the foot for a complete and irreparable degloving injury of the thumb; and selection of the radial forearm flap for multiple finger lesions. Between 1981 and 1993, 13 patients were treated for degloving injuries of the hand and fingers. Revascularization of the avulsed structures was possible in only 4 patients. In 6 patients with degloving injuries of the thumb in whom replantation was not possible, the thumb was reconstructed using a free wraparound flap from the big toe. In 3 patients with degloving injuries of the fingers, coverage was obtained as an emergency measure using an island radial forearm flap. In conclusion, replantation should be attempted when the degloved skin is available and the vessels are not damaged; secondary reconstruction should be done as early as possible to limit the time of tendon, bone, and joint exposure.

Partial arthrodeses of the wrist

The authors report 16 cases of partial arthrodeses of the wrist for the treatment of Kienboeck's disease, pseudarthrosis of the scaphoid, rotatory subluxation of the scaphoid, rheumatoid arthritis, etc. Based on the good results obtained (76.6%) the authors believe that partial arthrodeses constitute the type of treatment indicated for the treatment of pathologies that involve only some of the carpal bones, and they also emphasize that this type of surgery represents a valid alternative to total arthrodesis of the wrist.

A comparative study of the heterodigital neurovascular island flap in thumb reconstruction, with and without nerve reconnection

41 heterodigital neurovascular island flaps were used to cover defects of the tactile pad of the thumb in 17 years. With an average follow-up of 75.5 months, 30 patients were reviewed. 17 were treated by the original Littler technique and 13 were treated with the same flap reconstruction but with division of the digital nerve innervating the flap and re-anastomosis of this nerve to the proximal nerve end of the ulnar digital nerve of the thumb. Good aesthetic and functional results were achieved in both groups. Sensory acuity did not appear to decrease with time. The nerve reconnection technique solves the "double sensibility" phenomenon (present in 41.1% of our cases treated by the original technique), but two-point discrimination is less than that achieved by the Littler technique. Most complaints were related to the donor site such as hypertrophic scarring or scar contracture and cold intolerance, but these did not cause any real functional impairment.

Dorsalis pedis flap with vascularized extensor tendons for dorsal hand reconstruction

We describe three cases of combined loss of skin and tendons on the dorsum of the hand treated with the use of cutaneotendinous dorsalis pedis free flap. The functional and aesthetic results are excellent in the hand and aesthetically acceptable in the foot. This technique is the first choice when the treatment of these injuries requires three or four tendon grafts.

Replantation and revascularization of large segments of the hand and forearm

From November 1985 to July 1989, the authors performed replantation or revascularization surgery on 18 patients in whom a large segment of the upper limb between the elbow and the palm of the hand had been either completely severed (9 cases) or incompletely severed with ischemia (9 cases). The operation was successful in 16 cases, and the authors were able to clinically review 14 patients (average follow-up, 23 months). The results were analyzed using a protocol based on the following parameters: range of motion, sensation, muscle strength, cold intolerance, pain, return to work, cosmesis, and the patient's level of satisfaction. The final outcome was rated excellent in 2 cases, good in 6 cases, fair in 3 cases, and poor in 3 cases. The authors point out that recovery of sensory and motor function in replantation of large portions of the hand and forearm is often difficult. Nevertheless, the good cosmetic result, the lack of pain, and the high probability of returning to work made the patients quite satisfied with this kind of reconstructive surgery.

Neurovascular island flap by the disconnecting-reconnecting technique

The authors report nine cases of hetero-digital neurovascular island flaps raised by the "disconnecting-reconnecting" technique for defects of the tactile pad of the thumb. At an average follow-up of 25 months, all cases had good restoration of sensibility without any "double sensibility" phenomenon and patients regained good dexterity. No tender neuromata developed and donor site complications were not troublesome.

Neurovascular Island Flap by the Disconnecting-Reconnecting Technique

The authors report nine cases of hetero-digital neurovascular island flaps raised by the “disconnecting-reconnecting” technique for defects of the tactile pad of the thumb. At an average follow-up of 25 months, all cases had good restoration of sensibility without any “double sensibility” phenomenon and patients regained good dexterity. No tender neuromata developed and donor site complications were not troublesome.

Transfer in emergencies of the left ring finger to the right thumb. Case report

The authors report a case of serious crushing of both hands treated in emergency situation with transfer of the left ring finger, which could not be replanted, to the right thumb, as well as revascularization of the four fingers of the right hand.

Proposition for a new continuous suturing technique for microvascular anastomosis: a comparative study

The authors describe a suturing technique for end-to-end anastomosis in small vessels, which involves the use of continuous suturing without resorting to rotation of the approximator. The method is described in detail.

Simultaneous radioimmunoassay of serum testosterone and 5 alpha-dihydrotestosterone without chromatography

When characterization of the specificity of an antiserum for radioimmunoassay (RIA) is performed by the conventional method, the conditions under which interference occurs are not respected because of the lack of specific antigen. We have studied the behavior of antisera reproducing the real environment existing in unknown samples, in which antigen, interferent and tracer complete simultaneously. A testosterone (T) antiserum and a 5 alpha-dihydrotestosterone (D) anti serum were characterized by setting up two distinct hapten recovery tests in the presence of both the hapten and the crossreactant added to steroid-free serum in various concentrations in order to reproduce multiple concentration ratios. These samples, together with the standard curves samples (prepared by 'spiking' steroid-free serum with known concentrations of T or D) were extracted and subjected to T-RIA and D-RIA without purification. The results have shown that the interferent-induced incremental ratio is a linear function of the ratio of the levels of cross-reactant and hapten via a proportionality factor inversely correlated to the antiserum specificity. By means of this function, the overestimated T and D levels found in samples after 'extraction only' have been corrected and the resulting values have shown acceptable correlation with the corresponding levels determined after column chromatography.

Non-specific count subtraction in radioimmunoassay (a criticism)

The radioimmunoassay (RIA) blank (Blk) value (as calssically determined) does not represent the real aspecific portion of the radioactivity because of the lack of both antigen and antiserum and the consequent total availability of free tracer, and is, therefore, unlike the standard and unknown tubes. Gastrin-RIA with bound-free separation by charcoal adsorption was chosen as example for providing evidence that the subtraction of such an empirical constant (Blk) from the dependent variable (the response) of a function (response versus dose) is analytically incorrect. Antigen-recovery and parallelism (serum dilution) tests were carried out, and the results obtained by the so-called "Blk subtraction procedure" (BS values) were compared with the corresponding values without Blk subtraction (BNS values). In the recovery test, the BS values were higher than the BNS values, but the former were higher than the expected values, whereas the latter showed a quantitative recovery. The same result was also found in the serum dilution test: the BNS values gave dilution curves more parallel to the BNS standard curve than did the BS values to the BS standard curve. It is concluded that the Blk subtraction procedure must be avoided in processing RIA results.

Experimental determination of the operative parameters for a double antibody solid phase radioimmunoassay of luteinizing and follicle-stimulating hormones in serum

The experimental parameters of a Double Antibody Solid Phase (DASP) radioimmunoassay (RIA) for the determination of serum luteinizing (LH) and follicle-stimulating (FSH) hormones, are described. The lowest detection limits can be fixed at about 20 pg LH and about 10 pg FSH. Evidence of parrallelism among the dose-response curves and the dilution curves of different sera is provided for FSH-RIA and for about 92% of the tested sera for LH-RIA. The antisera dilution curves are reported (final titres: (/160 - 10(3) for anti-LH and 1/40 - 10(3) for anti-FSH). The traditional cross-reaction study in buffer indicates that 5.38 and 46.8) muU TSH/ml mimic 1 ng LH/ml and 1 ng FSH/ml respectively. The regression-line equations of antigen recovery (f = found, e = expected) are: lH f = 0.94 LH e + 0.91 and FSH f = 1.05 FSH e + 0.17; the same equations when TSH is added become: LH f = 1.30 LH e + 1.46 and FSH f = 1.40 FSH e -- 0.37. It is concluded that LH-RIA is interfered by TSH over 8-10 muM TSH/ml and in function of TSH concentration; FSH-RIA is not interfered by TSH up to 4-5 ng FSH/ml; for higher FSH levels, TSH interferes according to a linear law (angular coefficient 1.40) and not in function of its concentration. LH and FSH levels throughout normal menstrual cycle in follicular phase, centre peak and luteal phase are: 3.14 +/- 1.16, 16.71 +/- 12.99, 2.31 +/- 1.04 ng LH/ml (mean +/- 2SD) and 3.57 +/- 0.95, 5.72 +/- 2.90, 2.57 +/- 0.80 ng FSH/ml (mean +/- 2SD) respectively. Finally, the within-assay coefficient of variation is 7.65% for LH-RIA and 3.16% for FSH-RIA.