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N-glycolneuraminic acid (Neu5Gc) is a sialic acid mainly found in mammalian species. It is absent in humans. This is due to an irreversible mutation of the CMP-Neu5Ac hydroxylase (CMAH) enzyme in humans, rendering them unable to synthesize Neu5Gc. The human body identifies Neu5Gc as “foreign”; and anti-Neu5Gc antibodies are produced by the human body in response to any metabolically incorporated, diet-derived Neu5Gc, as found in ingested red meats and dairy products.Varying quantities of Neu5Gc is found in some approved biotherapeutics used for the treatment of numerous medical conditions. This leads to the debate of potential risks and/or benefits of Neu5Gc in humans. The effects of the interaction between anti-Neu5Gc antibodies and antigenic Neu5Gc-containing biotherapeutics in humans are largely unknown and there are many discrepancies in terms of scientific evidence. This article reviews and discusses the current knowledge in the understanding of Neu5Gc in the human body and its potential significance.

A free vascularized fibular bone transfer was successfully performed in a 1-year-old child to reconstruct the loss of the right humeral shaft following neonatal osteomyelitis. Subsequent growth of the child resulted in gross arm length discrepancy, with associated functional deficits. Callostatic distraction-lengthening of the vascularized fibular graft was carried out to compensate for this limb length discrepancy by using an Ilizarov external fixator. Lengthening of 6 cm over a 3-month period, representing a 75% increase in the original length of the transplanted fibula, was achieved. Active bone regeneration, good corticalization and endosteal medullary cavity formation was observed in the lengthened fibula. The combined modalities of vascularized bone transfer and Ilizarov callostatic distraction-lengthening offer a solution for reconstruction for large segmental bone loss associated with growth arrest of the epiphyseal plates in children.

This study looks at the effect of metamerism in colour-matching and the assessment of multi-layered silicone rubber finger prostheses. The aim was to identify the choice of illuminants for colour matching the prostheses that would give rise to the least metameric effect between the prostheses and the human skin or the best colour match. The prostheses were prepared and colour matched to a fair-skinned subject under 3 reference illuminants--TL84, D65, F and a combination of illuminants--TL84, D65 and F. The prostheses were then measured for colour using a spectrophotometer based on the CIE indices L*, a*, b* with each prosthesis assessed separately against the subject's index finger under the reference illuminants--TL84, D65 and F. The prostheses were also assessed by a panel of 50 observers and scored according to colour-match. Colour differences between the skin and prosthesis were measured in the illuminant under which the prostheses were prepared and then under the other reference illuminants. A relationship was obtained between the measured mean colour difference, deltaE*, and the mean visual assessment score for each prosthesis. This paper points out the concerns related to the optical phenomenon of metamerism with the colour pigments used. This can affect the colour match of the prosthesis as perceived by the patient. The findings seem to suggest that this metameric colour difference can be minimised if the prosthesis is matched under a combination of lights, which were found to give the best-perceived match.

A combined one stage anterior and posterior approach was used to excise a giant cell tumor involving the second lumbar vertebra. The tumor involved the anterior and posterior elements of the vertebra. A wide excision was feasible with immediate stabilization using the Luque instrumentation posteriorly and fibular strut grafts supporting the vertebral bodies anteriorly. The followup period was 13 years. There is no recurrence, and the patient has no symptoms of disease, and the fibular grafts are fully incorporated.

Microsurgical reconstruction of the severely mutilated, hand aimed at improving prehensile functions often does not address the esthetic aspects of the hand. The poor appearance of the reconstructed hand affects its active display and use. A, hand-glove prosthesis may be prescribed in this instance to enhance the overall form and function of the mutilated, hand. We reviewed 16 cases of mutilating hand injuries in which surgical reconstructions were performed and the patients were subsequently fitted with a hand-glove prosthesis to augment the outcome. An improved appearance, was achieved in all patients fitted with the prosthesis. The patients' sense of confidence was also enhanced, which in turn promoted the active and open use of the reconstructed hands. While prescribed primarily to improve the appearance of the reconstructed hands, these prostheses were documented to enhance the physical hand functions, in 11 cases by increasing the span of the hand and providing and opposable post and a palmar base for holding and for anchorage. The prosthesis enhanced assitive functions of the reconstructed hands and free the contralateral normal hand for use in bimanual activities, such as holding a wallet and taking out money supporting a note pad for writing, and holding a plate at buffet receptions. At the 18-month follow-up visit, 12 (87%) of the patients continued to use their prosthesis. Wear and tear were problems associated with the frequent use of the prosthesis. The expected life span of the prosthesis with daily use ranged from 2 to 3 years. All the patients acknowledged that the prosthesis played a role in their rehabilitation and that it helped them to overcome the initial psychological trauma and to come to terms with their physical loss.

Fixation of small bones in the adult and the child’s hands remains a challenge. The authors present a technique of bone fixation using customized staples made intraoperatively from K-wires (0.9–1.6 mm in diameter). Their specific purpose was to provide axial alignment and rotational stability for carpal bone fixation and for epiphysiodesis in phalanges. This technique was used in 14 cases (11 adult and three paediatric). No bone shattering, implant breakage, implant loosening or infection occurred. As K-wires are quite malleable, custom sized and shaped staples which follow the bone contours could be made to give a more exact fixation. All cases had satisfactory outcomes, achieving the preoperative objectives of bony fixation. This method is safe, precise and technically easy. It is also relatively cheap and only requires simple, standard instruments.

The appearance of the skin is dependent on the optical properties of the various layers of tissue and the presence of pigments. In order to reproduce the lifelikeness of the skin in developing digital prostheses, a multiple layered moulding technique was utilised. The prosthesis was moulded in two coloured layers, an outer layer and an inner layer. Four combinations of multiple coloured layers and two single coloured layers varying in their optical properties and base colours were assessed. In two groups an additional intermediate layer of detailed colours was added between the two layers, to enhance the creaselines, nails, blood vessels, and other features. All prosthesis were moulded to a total thickness of 0.6 mm. This method of moulding was based on the anatomical characteristics of the epidermal and dermal layers of the skin and their optical characteristics. The aim was to determine which combination of multiple layers gave the best outcome and made the prosthesis look lifelike in appearance. The appearance and lifelikeness of the prostheses were qualitatively assessed by a panel of assessers divided according to their vocation. The study showed that the best combination for moulding the prosthesis in multiple layers was to have the outer layer translucent and the inner layer opaque. An intermediate layer should be incorporated to enhance the more prominent surface features and the nails. The base colour of the inner layer should be darker than the outer layer to allow the intermediate layer to have a reflective background.

This study examines our clinical experience of fitting 136 digital prostheses in 90 patients. The careful selection of patients, especially concerning their expectations, is the single most important factor for successful prosthetic development for physically suitable candidates. Whether continued disability is due to physical loss or to its emotional impact, the socioeconomic consequences are similar, so attention to both is required. In a review of 30 patients fitted with digital prostheses after a minimum follow-up time of 2 years, it was found that 22 (73%) used their prostheses daily and another 7 (23%) used them intermittently according to the occasion. Thus, a total of 29 (97%) of those fitted with our digital prosthesis continued to use them after 2 years. Technical problems, such as loose fit and perspiration, resulted in 7 (23%) of the patients using the prostheses only occasionally. Fitting a prosthesis goes beyond aesthetics, and our study confirmed that digital prostheses, if of high quality, can alone or in conjunction with appropriate surgical reconstructions restore near normal appearance and form, substantially repair damaged body image, and simultaneously improve physical capability.

Between June 1978 and July 1991, 64 limb reconstructions were done using vascularized fibular grafts. Of these, 10 became infected. Five grafts were proven viable, whereas the other 5 were proven nonviable based on the survival of the skin in the composite osteocutaneous graft and from bone scans, angiograms, and biopsies. A distinct difference in the radiologic manifestation and clinical course of the infection was noted between the viable grafts and nonviable grafts. The viable grafts showed radiologic changes of osteomyelitis that were localized, and the graft incorporated, healed with antibiotics, and exhibited graft hypertrophy. In the nonviable grafts, the radiologic changes were extensive, evidence that resorption of the grafts had resulted. This suggests that, because of the poor prognosis associated with infection of the nonviable vascularized fibular grafts, the infected grafts should be removed early to minimize the morbidity and to shorten the protracted course associated with infection. With the infected viable grafts, efforts at salvaging the graft with multiple debridements and systemic antibiotics were rewarding.

The wide range of skin tones in the Asian population presents a challenge when colour-matching hand and finger prostheses. It requires that the prostheses be custom-made to better match the wide variations. We have developed a finger and hand prosthesis using a multi-layered moulding technique incorporating a colour-matching procedure capable of reproducing the colour tones and life-like appearance of the skin. Between 1990–1994, we have fitted these prostheses to a total of 109 patients. In evaluating the colour-match of their prostheses, 84% of the patients fitted with hand prostheses and 78% of those fitted with finger prostheses had a good to excellent match. This paper discusses some of the challenges we face in colour-matching hand and finger prostheses in the Asian population.

The musculocutaneous nerve and its motor branches to the biceps and brachialis were dissected and studied under the operating microscope in 24 fresh-frozen cadaveric specimens. The motor branch to the biceps exits from the musculocutaneous nerve at 119 mm distal to the coracoid process. Anatomic variations were seen in the innervation of the two heads of the biceps. A common primary motor branch that bifurcates to supply the two heads was seen in 20 specimens (type I). Two specimens were observed to have two separate primary branches originating from the main musculocutaneous nerve trunk to individually supply each head of the biceps (type II). The third variation, two specimens (type III), was observed in two specimens to be similar to type I, but with an additional distal motor branch innervating the common belly of the biceps muscle. The motor branch to the brachialis muscle exists from the musculocutaneous nerve 170 mm distal to the coracoid process. A single primary motor branch (type I) was seen in 23 specimens, and 1 specimen (type II) showed two separate primary motor branches innervating the muscle. The motor branches to the biceps and brachialis muscles may be dissected proximally from their points of exit from the main trunk of the musculocutaneous nerve for a mean distance of 44 mm and 53 mm, respectively. This information can be used by surgeons who elect to suture intercostal nerves to the motor branches of the biceps and brachialis muscles for elbow flexion in brachial plexus injuries.

In four complex cases of extremity reconstruction, we have been able to overcome the problems of combined bone and soft-tissue loss and length discrepancy by a combination of free-tissue transfer and the Ilizarov method of slow distraction. It is our observation that gradual distraction of a free tissue is a safe and viable procedure; the free tissue tolerates the pins of the circular external fixator well, and there is an equal degree of distraction and regeneration of the transferred free tissue and the native recipient tissue without evidence of wound dehiscence. Corticotomy through free tissue and in close proximity to vascularized bone is safe, with the subsequent bone regeneration not unlike that of normal bone. Manipulation by slow distraction does not appear to compromise the vasculature of the recipient bed for later microsurgical procedures or endanger the axial flow pattern of the transferred free tissue.

We report a case of reconstruction of the humeral shaft by soft tissue lengthening according to the method of Ilizarov, followed by skeletal reconstruction with a vascularized fibular graft. Skeletal union and initiation of functional activity were achieved within 4 months. Lengthening of the soft tissue and the vascular tree by slow distraction did not compromise the subsequent reconstructive microsurgical procedure.

A method for creating a model for fabricating a partial hand glove prosthesis is described. The realigned casts of the corresponding digits of the contralateral uninjured hand were used to substitute for the lost digits on a cast of the stump. The technique allows an exact reproduction of the anatomical and fine surface details of the digits. It has the advantage of customisation, allowing a close match in the size, shape and surface characteristics of the prosthesis to that of the remaining digits of the hand.

We present our experience with limb salvage emphasising the use of vascularised bone grafts in combination with autoclaved tumour bone for limb salvage in osteosarcoma.Thirty-six cases with extremity osteosarcoma, all of which were managed at a single institution between 1980 and 1999, were reviewed at a mean follow-up of 9 years (range, 10 months to 200 months). There were 26 patients who underwent limb salvage surgery and 10 patients who had amputation.In the limb salvage group, 12 bone defects were bridged using vascularised bone grafts alone while autoclaved tumour bone was used for reconstruction in the remaining 14 patients. In these 14, there were 10 with autoclaved tumour bone and vascularised bone, 2 with autoclaved bone and non-vascularised bone and 2 with autoclaved bone alone. The joint was preserved in 13 of the 26 reconstructions. Of these, 11 involved preservation of the knee joint contributing to a quantum gain in function with 84% good and excellent results. The actuarial survival was 64% at 2 years and 48% at 5 years, with no significant difference between ablation and limb salvage.The use of the autoclaved bone provided yet another effective alternative for bridging large defects following resection of high grade tumours.

This paper reviews the authors' experience with fitting life-like finger and hand prosthesis. The methodology and technical considerations in producing these prostheses, the prosthetic prescription according to the level of amputation and the challenges faced with each level are discussed. In cases where the amputation is sufficiently distal, a thimble prosthesis has been used. This is compared to fitting a full-length finger prosthesis. Besides allowing free range of motion of the proximal finger joints which would otherwise be covered and restricted with fitting a finger prosthesis, a thimble prosthesis minimises skin coverage for optimal sensibility and is easier to don and doff. In cases of amputations where a digital fitting is precluded, a partial or a total hand is prescribed. A comparison between fitting a finger, a partial hand prosthesis and a total hand prosthesis is also discussed. Cases of a digital, transcarpal and a more proximal transmetacarpal amputations are relatively easy to fit with a prosthesis. An incomplete transmetacarpal amputation where much of the breadth of the hand is preserved presents a difficult challenge as it necessitates fitting with a partial hand prosthesis. Besides the need to cover a large area of the intact skin and the associated problems with reduced sensibility and stump perspiration, a partial hand prosthesis is difficult to don and doff.

The fungal discolouration of silicone rubber prostheses is reported in four cases. In two of the cases, the discolouration was caused by the fungus Candida tropicalis. In the other two cases, two different fungal organisms, namely Trichoderma sp. and Scedosporium prolificans were incriminated. The non-porous silicone rubber layers create an enclosed environment in the suction cup of the prosthesis and preclude ventilation at the prosthesis-stump interface. The moisture as a result of sweat and body warmth in the stump assists fungal growth. Residual salts from the sweat, sebum from sebaceous glands and the residues from petroleum jelly (Vaseline) applied to facilitate donning, can adhere to the surfaces of the prosthesis and provide the nutrients for fungal growth. Prolonged continuous usages of the prosthesis, the presence of sweaty palms in the users, donning the prosthesis during manual physical activities which induce perspiration, washing of hands with the prosthesis on and warm humid climatic conditions have been identified as factors predisposing the prosthesis to fungal colonisation. The fungal growth caused a black discolouration and marred the aesthetic quality of the prostheses. As a preventative measure, daily immersion of the prostheses in denture cleaner such as benzalkonium chloride, or water at 60 degrees C for 15 minutes, or decontamination with 70% alcohol is recommended. Prior cleaning to remove organic matter before decontamination is emphasised.

Two adult patients with post-traumatic complete brachial plexus injury were treated with cross-C7 nerve-root transfer from the contralateral side. A detailed documentation of the motor and sensory functional status of the donor upper limb was carried out before and after division of the C7 nerve root. Gross motor deficits were observed immediately after surgery in shoulder extension and adduction, elbow extension, forearm pronation, wrist flexion, and hand movement. Sensory deficit involving the hand was maximal immediately after division of the C7 root. Functional recovery was rapid starting within 10 days following the root division. In both patients, the motor and sensory deficits were temporary. Full functional recovery was documented at 6 months. However, objective qualitative and quantitative differences in the motor and sensory deficits in the donor limbs were still present by 1.5 to 2 years, although these did not affect the functional status of the donor limbs. The presence of multiple segmental root innervation of the muscles and skin, other than the C7 root in the upper limb, provides for a compensatory mechanism that allows for this rapid and full functional recovery following the single nerve-root loss. The absence of any long-term functional deficit makes cross C7 transfer a viable option in the surgical management of complete unilateral brachial-plexus injury.

Twenty-five hand infections in adult patients with diabetes were reviewed. Eighty percent of the patients were younger than 60 years of age and had diabetes mellitus for less than 5 years' duration. Secondary neurologic, vascular, or cutaneous changes in the hands were present in 5 (20%) patients. A documented instance of trauma was present in 16% of patients. None of the patients had nosocomial infections. Of the 24 (96%) patients who required surgery, 21 had debridement alone and 3 needed amputation of the digit or digits or hand, either as a primary procedure or after initial debridement. Multiple organisms were found in 55% of the positive cultures. Gram negative organisms were documented in 73% of the positive cultures. An antibiotic combination of gentamicin, penicillin G, and cloxacillin covered the entire spectrum of the causative organisms. An aggressive treatment protocol comprising hospital admission, intravenous combination antibiotics, surgical debridement, appropriate diabetic control, and strict elevation of the hand was important in the management of the sepsis, reduction of morbidity, and salvage of the hand. With a followup at 2 years, there was no instance of any repeat episode of the hand infection.

A composite free latissimus dorsi musculocutaneous flap combined with Ilizarov lengthening was used in the resurfacing of the elbow and the reconstruction of the forearm following a very proximal below elbow amputation with soft tissue degloving to the level of the mid arm. The free flap provided gliding soft tissue to the elbow joint, and the deep fascia and muscle components of the flap were contoured round the bony stump so as to allow bone transport within the soft tissue envelope. The lengthening achieved was 14 cm with no bone resorption at the end of the stump. The reconstructed forearm, with a well-contoured stump covered with durable and adherent soft tissue, allowed the fitting of a forearm-based lightweight hand glove prosthesis. With the combined modalities of microsurgical free tissue transfer, the Ilizarov method of slow distraction and prosthetic fitting, we were able to achieve restoration of both form and function in a difficult case of major upper extremity amputation.

We report our results using University of Wisconsin (UW) cold storage solution in two cases of major replantation of the upper extremity. We employed a technique of a complete vascular washout with 1000 ml UW solution at 4 degrees Celsius at 120 cm hydrostatic pressure into the artery via a size 18 cannula. The ischaemic time of the amputated limbs were 7 hours and 11 1/4 hours respectively. No fasciotomy was performed upon revascularisation and minimal swelling was observed postoperatively. No post-ischaemic syndrome was encountered following the replantation surgery. With a follow-up of 10 and 16 months respectively, muscle and nerve viability were observed with sensory recovery and motor reinnervation. There was absence of muscle contracture and at subsequent surgical procedures, healthy musculature was present in the replanted limbs. These two clinical cases suggest that the UW solution has a role in extending the duration of tissue preservation and improving the quality of the tissues preserved.

We performed 10 digital replantations under local anaesthesia. Nine were single digit replantations and one case had a digital replantation together with another digit revascularisation. Criteria for patient selection for the local anaesthetic procedure included healthy young individuals, solitary hand injury, ability to understand the procedure and a stable emotional makeup. A combination of 10 ml of lidocaine 1% and 10 ml of bupivacaine 0.5% was used for volar metacarpal block and a dorsal ring block to the base of the digit. The patient was simultaneously sedated with 10 mg diazepam intramuscularly. Standard intraoperative monitoring of blood pressure, continuous electrocardiogram and pulse oximeter were carried out. The average duration of surgery was 3 hours. There was complete pain relief intraoperatively and good postoperative sensory block for an additional 7 to 15 hours. The technical execution of microsurgery was not compromised. All replantations were successful with no complication encountered from the use of local anaesthesia.

This case report describes a patient who had a painful and fungating angiosarcoma of the right buttock. A palliative hindquarter amputation was performed. A large, free flap taken from the amputated leg was used to cover the defect. This technique offers a solution for covering large defects in an unsalvageable traumatic amputation or tumor conditions.

Ten cases of bipolar forearm fracture-dislocation are presented. Recognition of the full extent of the skeletal, articular, and soft-tissue injuries is essential. Treatment consists of an anatomical reduction and proximal and distal stabilization of the skeleton to achieve control as well as maintain the position of the floating radius segment. The forearm bones can then be maintained in an optimal position to avoid interosseous soft-tissue contracture that will compromise the supination-pronation function of the forearm.

The vascular anatomy of the radial forearm flap, incorporating the brachioradialis and palmaris tendons together with the superficial radial nerve in 20 fresh cadavers, is described. The radial artery in the cadaveric forearm was irrigated and injected with blue latex. The number and distribution of the cutaneous branches supplying the skin, brachioradialis tendon, palmaris tendon, and superficial radial nerve, were then documented in relation to the distance from the radiocarpal joint. The radial artery was found to provide adequate blood supply to the above structures. This flap has been used as a composite neuro-teno-cutaneous flap to resurface a large defect involving tendon, nerve, and skin loss in the ankle and the foot as a one-stage procedure. This technique avoids multiple-staged operations and thus shortens the convalescent period in rehabilitation of severely traumatized limbs.

The value of limb-preservation procedures for primary bone tumor around the knee is well established. Procedures of skeletal reconstruction include arthroplasty using custom-made prostheses, allograft for hemijoint transfer, and arthrodesis. Resection in the presence of a large bony defect is often associated with complications such as infection, nonunion, graft dissolution, and stress fracture. Many of the complications are related to the type of bone graft used and the extent of defect. Our experimental and clinical studies have shown that the use of vascularized bone graft will minimize these problems.

In this study, the authors investigated enhancing the results of autoclaved autograft bone by combining it with a vascularized bone graft and supplementing it with autogenous bone marrow for replacement of a 2-cm tibial defect in the rabbit model. The study was divided into 4 groups. Group I consisted of autoclaved autograft bone only; Group II, autoclaved autograft bone and vascularized bone graft; Group III, autoclaved autograft bone and autogenous bone marrow; and Group IV, autoclaved bone and autogenous bone marrow and vascularized bone graft. The vascularized bone graft was provided by the ipsilateral fibula, pedicled on the peroneal vessels, and transposed to sit alongside the autoclaved bone. In Group I, all grafts had nonunion at 16 weeks. In Group II, new bone formation was seen at the proximal and distal site of the autoclaved bone, host bone, and vascularized fibular graft junction as early as 2 weeks, and bony union occurred at the 16th week. The autogenous bone marrow-supplemented groups (III and IV) had new bone formation along the entire length of the autoclaved bone. Bony union at the proximal and distal junction was seen as early as 4 weeks, extending to the entire autoclaved bone by the eight week (98% of the cases with 1 case of infection). Histologic examination showed revascularization and capillary ingrowth into the autoclaved bone at 16 weeks, with a significantly improved torsional stiffness when compared with the groups without autogenous bone marrow supplementation. The addition of vascularized bone graft resulted in an improved union rate as compared with the autoclaved bone alone. Autogenous bone marrow supplementation, in addition to the vascularized bone graft, resulted in rapid new bone formation all around the autoclaved bone, early revascularization and incorporation of the autoclaved bone, and a significantly improved torsional stiffness of the reconstruction.

We describe preliminary observations on the use of free vascularised transfer of proximal fibular epiphysis in replacement of proximal humeral epiphysis or distal radial epiphysis in three patients. An analysis of the early results shows evidence of longitudinal growth, graft hypertrophy and epiphyseal adaptation in transplanted epiphysis. A review of the problems in this type of surgery is included.

We describe preliminary observations on the use of free vascularised transfer of proximal fibular epiphysis in replacement of proximal humeral epiphysis or distal radial epiphysis in three patients. An analysis of the early results shows evidence of longitudinal growth, graft hypertrophy and epiphyseal adaptation in transplanted epiphysis. A review of the problems in this type of surgery is included.