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Chow SP. Major breakthroughs in hand surgery. BMC Proc 2015. [PMCID: PMC4444980 DOI: 10.1186/1753-6561-9-s3-a6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Rajesh G, Ip WY, Chow SP, Fung BKK. TREATING DEEP-SEATEDMYCOBACTERIUM MARINUMINFECTION IN THE HAND: A REPORT OF THREE CASES. ACTA ACUST UNITED AC 2011; 11:83-8. [PMID: 17080536 DOI: 10.1142/s0218810406003140] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Accepted: 08/04/2006] [Indexed: 11/18/2022]
Abstract
We report three cases of an unusual aggressive type of Mycobacterium marinum infection of the hand which had been a nightmare both for us and the patient. These were the patients in which even after repeated thorough surgical debridement and appropriate (drug sensitive) medical treatment over a period had resulted in amputation or devastation of the soft tissues so extensively that almost only the neurovascular bundle, bone and the skin were the only structures left (cosmetic fingers — no function) at the last debridement after which the infection has not recurred. By presenting this article we want to stress on certain points pertaining to diagnosis, management, varied presentation and of course the dreadful complications of deep-seated M. marinum infection.
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Affiliation(s)
- Garg Rajesh
- Department of Orthopaedic Surgery, Hand and Foot Division, University Of Hong Kong, Queen Mary Hospital, Hong Kong, China.
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ur Rashid H, Leung F, Lu W, Fung B, Chow SP. BIOMECHANICAL EVALUATION OF PLATE OSTEOSYNTHESIS FOR AO TYPE C2 FRACTURE OF THE DISTAL RADIUS — A CADAVER STUDY. ACTA ACUST UNITED AC 2011; 8:151-6. [PMID: 15002090 DOI: 10.1142/s0218810403001650] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2003] [Accepted: 06/04/2003] [Indexed: 11/18/2022]
Abstract
An AO type C2 distal radius fracture was simulated in a cadaver model by creating a metaphyseal defect of 5 mm and an intra-articular defect of 2 mm. Five different methods of plate osteosynthesis were tested biomechanically in each of six fresh cadaveric hands. Biomechanical testing suggested that cement augmented plating plus screws in the distal fragment was the strongest. Dorsal and volar plating plus screws on both sides of the distal fragment had the same effect of restoring stiffness and load transmission pattern as fixation with double plating plus volar screws alone. Fixation with plating plus dorsal screws was significantly weaker than these three methods, and double buttress plating with no screws in the distal fragments was the weakest.
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Affiliation(s)
- Haroon ur Rashid
- Department of Surgery (Orthopedic Division), Aga Khan University Hospital, Karachi, Pakistan
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Fung BKK, Ho SMY, Fung ASM, Leung EYP, Chow SP, Ip WY, Ha KWY, Barlaan PIG. The development of a strength-focused mutual support group for caretakers of children with cerebral palsy. East Asian Arch Psychiatry 2011; 21:64-72. [PMID: 21838209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVE To examine the efficacy of a strength-focused mutual support group for reducing stress and enhancing psychological well-being of the caretakers of children with cerebral palsy. METHODS This pre- and post-intervention outcome study, conducted by Department of Orthopaedics and Traumatology, Duchess of Kent Children's Hospital, recruited 12 primary caretakers of children with cerebral palsy in Hong Kong. A strength-focused support group manual was developed to help such caretakers to identify and cultivate the character strengths of their children and enhance their own positive emotions. Participants were asked to complete a full set of questionnaires at 3 time-points: before and immediately after the intervention (consisting of 4 weekly sessions), and after the 1-month follow-up booster session. Two additional questionnaires were administered before each session to check mood. Parenting stress, anxiety, depression, social support, hope, and other psychological well-being measures were also assessed. RESULTS Half of the caretakers (n = 6) who had attended the full intervention programme were included in the data analysis. Participants exhibited a significantly lower level of parental stress and higher hope level both after the 4 intervention sessions and at the booster session. Their perceived social support was significantly increased when the group was ongoing but not after it ended. CONCLUSION This group intervention programme could effectively help caretakers reduce their parenting stress and enhance their hopefulness. Launching a similar programme with more sessions and regular follow-up sessions might help maintain positive effects and establish a social support network.
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Affiliation(s)
- B K K Fung
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, Hong Kong SAR, China.
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Abstract
The effect of delay of surgery on the geriatric hip fractures has been a subject of interest in the past two decades. While the elderly patients will not tolerate long periods of immobilization, it is still unclear how soon these surgeries need to be performed. A review of existing literature was performed to examine the effect of timing of surgery on the different outcome parameters of these patients. Although there is conflicting evidence that early surgery would improve mortality, there is widespread evidence in the literature that other outcomes including morbidity, the incidence of pressure sores, and the length of hospital stay could be improved by shortening the waiting time of hip fracture surgery. We concluded that it is beneficial to the elderly patients to receive surgical treatment as an urgent procedure as soon as the body meets the basic anesthetic requirements.
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Affiliation(s)
- F Leung
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
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Lau TW, Leung F, Chan CF, Chow SP. Wound complication of minimally invasive plate osteosynthesis in distal tibia fractures. Int Orthop 2008; 32:697-703. [PMID: 17572892 PMCID: PMC2551726 DOI: 10.1007/s00264-007-0384-z] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 05/02/2007] [Accepted: 05/13/2007] [Indexed: 11/24/2022]
Abstract
Nowadays, the use of minimally invasive plate osteosynthesis (MIPO) in the management of fracture of the distal tibia is common. The various advantages of the MIPO technique, namely, preserving blood supply and better bone healing, have been described extensively in the literature. However, this technique is not without complication. Among all the complications, infection is one of the commonest. In the last 3 years, we have performed 48 cases of MIPO in treating distal tibia fractures. Our study was to evaluate the clinical outcome of these cases, with special attention to the infection rate and our experience in managing these infection cases. Our results showed that the average time until the patient started to bear full weight was 9.4 weeks. The average time for bony union was 18.7 weeks. There were 7 cases of late infection among these 48 cases. The rate was 15%. The presence of late infection had no obvious effect on the time to bony union. Twenty-five patients (52%) had the implants removed and the most common reason was skin impingement by the implant. The clinical presentation and management of these late infections are discussed. In conclusion, MIPO fixation of distal tibia fractures using a metaphyseal locking plate is safe and efficient. However, complications such as late wound infection and impingement are relatively common. The overall clinical outcome is still good despite the presence of these complications.
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Affiliation(s)
- T W Lau
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China.
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Cheung JPY, Fung B, Ip WY, Chow SP. Occupational repetitive strain injuries in Hong Kong. Hong Kong Med J 2008; 14:296-302. [PMID: 18685163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
OBJECTIVE To review currently available evidence on the epidemiology and management of occupational repetitive strain injuries with particular reference to Hong Kong. DATA SOURCES AND STUDY SELECTION Medline, PubMed and Cochrane Library searches of local and internationally published English journals from 1990 to 2007 regarding repetitive strain injuries. DATA EXTRACTION All articles involving occupational repetitive strain injuries in Hong Kong were included in this review. DATA SYNTHESIS There were 16 articles contributing data on the impact of repetitive strain injuries both in Hong Kong and around the world. There were seven articles dealing with the problem of computer station set-ups and methods for improving the workstation environments. CONCLUSION Currently there were significant data on the impact of repetitive strain injuries in Hong Kong. The data took the form of compensation claims, days away from work, and cost of medical consultations. Other articles described proper workplace adjustments to help prevent repetitive strain injuries. However, there were no figures in the current literature showing the impact of these adjustments in reducing the incidence of repetitive strain injuries. More research could help to delineate the relationship between different types of interventions and occupational repetitive strain injuries.
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Affiliation(s)
- Jason P Y Cheung
- Department of Orthopaedics and Traumatology, University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong.
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Ho SMY, Fung BKK, Fung ASM, Chow SP, Ip WY, Lee SFY, Leung EYP, Ha KWY. Overprotection and the psychological states of cerebral palsy patients and their caretakers in Hong Kong: a preliminary report. Hong Kong Med J 2008; 14:286-291. [PMID: 18685161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
OBJECTIVE To examine the relation between perceived overprotection and the psychological states of cerebral palsy patients and their primary caretakers in Hong Kong. DESIGN Cross-sectional survey, in which data of 14 pairs of cerebral palsy patients and their caretakers were analysed. SETTING Duchess of Kent Children's Hospital, Hong Kong. PARTICIPANTS Cerebral palsy patients and their primary caretakers in Hong Kong. MAIN OUTCOME MEASURES Perceived overprotection and psychological states. RESULTS Nearly two thirds of the 14 patients (mean age of 15 years) and 86% of the 14 primary caretakers (mean age of 47 years) perceived various levels of overprotection. For both patients and caretakers, perceived overprotection was positively associated with anxiety and unhappiness. The patients' and caretakers' psychological states and perception of overprotection were not related to the actual motor ability of the patients. Perceived overprotection of the patients was not related to that of the caretakers. CONCLUSION Caretakers should be mindful that a well-meaning move may have undesirable consequences. More support and child-rearing education should be considered for caretakers.
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Affiliation(s)
- Samuel M Y Ho
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, Pokfulam, Hong Kong
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Garg R, Fung BKK, Chow SP, Ip WY. Surgical management of radial head dislocation in quadriplegic cerebral palsy -- a 5 year follow-up. J Hand Surg Eur Vol 2007; 32:725-6. [PMID: 17993449 DOI: 10.1016/j.jhse.2007.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Revised: 04/20/2007] [Accepted: 05/09/2007] [Indexed: 02/03/2023]
Affiliation(s)
- Rajesh Garg
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, University of Hong Kong, Hong Kong, E-mail:
| | - Boris K. K. Fung
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, University of Hong Kong, Hong Kong, E-mail:
| | - S. P. Chow
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, University of Hong Kong, Hong Kong, E-mail:
| | - W. Y. Ip
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, University of Hong Kong, Hong Kong, E-mail:
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Abstract
PURPOSE To assess a protected mobilisation programme (dynamic treatment) for proximal phalangeal fracture of the hand, irrespective of the geometry. METHODS Clinical and radiological results of 32 consecutive patients with proximal phalangeal fracture of the hand treated from January 2001 to February 2007 were evaluated. Our supervised rehabilitation programme was strictly followed to gain full range of movement of the proximal interphalangeal joint and to prevent the development of an extension lag contracture. Patients were followed up for a mean period of 15 (range, 13-16) months. Results were evaluated using the Belsky classification. RESULTS The results were excellent in 72% of the patients, good in 22%, and poor in 6%. Some patients defaulted follow-up, which made long-term assessment difficult. The poor results may have been related to patient non-compliance or default from rehabilitation. Many good results upgraded to excellent following further rehabilitation. CONCLUSION Skeletal stability, not rigidity, is necessary for functional movements of the hand. Proximal phalangeal fractures can be effectively treated by closed methods, using the stabilising effect of soft tissues (zancolli complex-metacarpophalangeal retention apparatus) and external devices (metacarpophalangeal block splint), thus enabling bone healing and movement recovery at the same time.
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Affiliation(s)
- G Rajesh
- Department of Orthopaedics and Traumatology, University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong.
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Abstract
PURPOSE To evaluate the use of locking compression plates (LCPs) in diaphyseal forearm fractures. METHODS 9 women and 23 men (mean age, 35; range, 12-70 years) with 45 forearm fractures were treated by open reduction and internal fixation with 3.5-mm stainless steel LCPs. All patients were followed up monthly until union; the mean duration being 20 months. Radiographic assessment was performed at 3, 6, 12, and 18 months. Clinical assessments regarding pain and function were undertaken at the final follow-up. RESULTS Two patients had delayed union but none had nonunion. There was no deep infection and only one superficial infection. Two refractures occurred after implant removal, both were of simple transverse type and at the sites of the original fractures. 33% of the fractures were reduced anatomically. 56% of the fractures healed with no or minimal callus formation and 44% with moderate callus formation. In total, 13% of the anatomically reduced fractures had moderate or abundant callus formation. 22 patients opted for removal of the implants (29 LCPs), after a mean of 16 (range, 9-21) months. CONCLUSION The LCP is an effective bridging device used for treating comminuted fractures, but for treating simple fractures its superiority over conventional plating is yet to be proven.
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Affiliation(s)
- F Leung
- Division of Orthopaedic Trauma, Department of Orthopaedics and Traumatology, Queen Mary Hospital, The University of Hong Kong, Hong Kong.
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Lau TW, Leung F, Chan CF, Chow SP. Minimally invasive plate osteosynthesis in the treatment of proximal humeral fracture. Int Orthop 2006; 31:657-64. [PMID: 17033765 PMCID: PMC2266656 DOI: 10.1007/s00264-006-0242-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 07/23/2006] [Accepted: 07/24/2006] [Indexed: 10/24/2022]
Abstract
The management of fractures of the proximal shaft of the humerus has been evolving since the development of new techniques and new implants in recent years. It seems that this kind of fracture has an increasing incidence in the older, osteoporotic population. In the last 2 years, we have operated on 17 patients, with an average age of 65, who had proximal humeral shaft fractures treated by minimally invasive percutaneous osteosynthesis (MIPO) technique using the metaphyseal locking compression plate. Our study evaluated the surgical technique used and the outcome for these patients with regards to their range of movement and shoulder function. Our results showed that all the patients could achieve at least 140 masculine of shoulder abduction in the first 6 months after the operation, except for three patients who had shoulder impingement. These patients had an average Constant score of 76.8. All fractures had bony union at 6 months, except one, which was probably due to poor reduction in the initial operation. Another complication that we encountered was radial nerve neuropraxia. The ways to prevent these complications are discussed. In conclusion, MIPO fixation using the metaphyseal locking compression plate is a good option for the management of proximal humeral shaft fractures. It provides early functional recovery, but we had to pay special attention to some of the surgical details in order to minimise complications.
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Affiliation(s)
- T W Lau
- Department of Orthopaedic and Traumatology, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, PR China.
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Ning CY, Wang YJ, Lu WW, Qiu QX, Lam RWM, Chen XF, Chiu KY, Ye JD, Wu G, Wu ZH, Chow SP. Nano-structural bioactive gradient coating fabricated by computer controlled plasma-spraying technology. J Mater Sci Mater Med 2006; 17:875-84. [PMID: 16977384 DOI: 10.1007/s10856-006-0176-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2005] [Accepted: 08/23/2005] [Indexed: 05/11/2023]
Abstract
The poor mechanical property of hydroxyapatite was the major problem for load bearing and implant coating in clinical applications. To overcome this weakness, a bioactive gradient coating with a special design composition of hydroxyapatite (HA), ZrO2, Ti, bioglass was developed. This 120 microm coating with an upper layer of 30-50 microm porous HA produced by computer controlled plasma spraying which maintained energy level of the plasma which ensure proper melting of powder. The crystal size of the coating was 18.6-26.2 nm. Transformation of t-ZrO2 to m-ZrO2 reduced the thermal stress that weakened the coating and lowered down interfacial strength of the coating and metal substrate. Thermal stress of sprayed coating was 16.4 MPa which was much smaller than the sample without thermal treatment of 67.1 MPa. Interfacial strength between the coating and metal substrate was 53 MPa which is much higher than conventional Hydroxyapatite coating. Based on XRD analysis crystallinity of HA approached 98%. Therefore, high temperature treatment improved long term stability of the coating through improved crystallinity of hydroxyapatite and reduced other impure calcium phosphate phase.
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Affiliation(s)
- C Y Ning
- Department of Orthopaedics & Traumatology, University of Hong Kong, Hong Kong
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Chow SP, Lam KW, Gibson I, Ngan AHW, Lu W, Ip WY, Chiu KY. A novel artificial prosthetic replacement for the proximal interphalangeal joint of the hand--from concept to prototype. Hand Surg 2006; 10:159-68. [PMID: 16568509 DOI: 10.1142/s0218810405002814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Accepted: 09/01/2004] [Indexed: 11/18/2022]
Abstract
This article describes the development of a proximal interphalangeal (PIP) joint prosthesis based on the principles of replicating anatomical surface components, the use of macrolocking intramedullary stem and the use of a cobalt-chrome alloy material. The design features are intended to obtain an optimal range of motion while retaining stability and longevity. The final prototype, for which a patent has been filed, is described.
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Affiliation(s)
- S P Chow
- Department of Orthopaedics and Traumatology, Queen Mary Hospital, The University of Hong Kong, Pokfulam, Hong Kong SAR, PR China.
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Abstract
Nicolau syndrome (livedoid dermatitis) is a rare adverse reaction of a still largely unidentified pathogenesis at the site of intramuscular drug injection. The typical presentation is pain around the injection site soon after injection, followed by erythema, livedoid patch, haemorrhagic patch, and finally necrosis of skin, subcutaneous fat, and muscle tissue. The phenomenon has been related to the administration of a variety of drugs, including non-steroidal anti-inflammatory drugs, corticosteroids, and penicillin. We report a case of Nicolau syndrome following an intramuscular injection of diclofenac. The large ulceration over the right buttock was positive for Pseudomonas aeruginosa, and histology revealed subcutaneous fat necrosis and non-specific inflammation with no evidence of malignancy or vasculitis. The lesion required multiple debridements and a partial-thickness skin graft. Subcutaneous injection, rather than intramuscular injection, was found to be a determining factor in this case. Clinicians must be cautious in the use of proper injection procedures, including appropriate needle length, in order to minimise complications.
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Affiliation(s)
- C Lie
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
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Abstract
Torsion at the microanastomosis site is a basic fault and should be avoided. In this study, we investigate the effects of different degrees of microvenous torsion on patency and its physical changes on anastomoses in a rat model. One hundred anastomoses were performed at different degrees of torsion, using femoral veins of Sprague-Dawley rats. Anastomoses were performed at 0 degrees, 45 degrees, 90 degrees, 135 degrees, and 180 degrees of torsion randomly. Patency tests immediately, 1 h, and 1 week after the anastomoses were checked, using the refill test. Measurements of external diameter were recorded at three points: one at the anastomosis site, and the others 2 mm proximal and distal to the anastomotic site. Finally, histopathologic and scanning electron microscopy studies were performed. Subsequently, because of the peculiar phenomenon of early recannulation of the thrombosed vessels, 20 vessels were also explored on the first and the third days postoperatively. The data demonstrate that torsion at 180 degrees, compared with 0 degrees, 45 degrees, and 90 degrees, impaired patency significantly (P < 0.005). In the subsequent study of 20 veins that were thrombosed on the first day, all became patent on the third day and remained so. In conclusion, rotation of a microvenous anastomosis begins to affect the patency rate at 90 degrees of torsion, and at 180 degrees has a patency rate of only 25%. However, all become patent again from the third day onwards. Thrombosis of rat femoral veins without chronic obstruction results in rapid lysis of thrombus and transient proliferative changes.
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Affiliation(s)
- S Sinan Bilgin
- Department of Orthopedic Surgery, Ankara University School of Medicine, Ankara, Turkey.
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Affiliation(s)
- S P Chow
- Department of Orthopaedic Surgery, The University of Hong Kong, Pofkulam, Hong Kong, China.
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Topalan M, Bilgin SS, Ip WY, Chow SP. An anatomic variation in the femoral vein of a Sprague-Dawley rat. Plast Reconstr Surg 2003; 112:347-8. [PMID: 12832928 DOI: 10.1097/01.prs.0000067102.50738.e1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
All kinds of technical faults must be prevented in microvascular anastomosis for successful reconstructive microsurgery. Torsion at the anastomosis site is one of the most basic technical errors. In this study, we investigate the effect of different degrees of microarterial torsion on patency and its physical changes on anastomosis in a rat model. A total of 144 microanastomosis were performed in 72 Sprague-Dawley rats. They were divided into 9 groups. The anastomosis was performed at 0 degrees, 45 degrees, 90 degrees, 135 degrees, 180 degrees, 225 degrees, 270 degrees, 315 degrees, and 360 degrees of torsion randomly. Patency rates and the narrowest point of the artery after the anastomosis were recorded after 1 hour for each group. In the second stage of the study, the 9 groups were divided into 2 groups for patency rates and histopathological sampling at the second and seventh days postoperatively. The femoral arteries in all groups were all patent at the end of 1 hour. Only 5 microanastomosis were thrombosed (one in the 45 degrees group, one in the 225 degrees group, one in the 270 degrees group, and two in the 315 degrees group) at the second day of exploration. Only two arteries were thrombosed (one in the 45 degrees group and one in the 315 degrees group) at the seventh day of exploration. The patency rate was 96.8% in experimental groups excluding the control group. Different degrees of torsion had no statistically significant effect on the patency rates of microvascular anastomosis. Torsional repair of the femoral artery in the rat has no significant histopathologic changes, but alternately, endothelial integrity was affected by excessive degrees of torsion. Different degrees of torsion at the anastomosis site do not affect patency rates and cross sectional histology of rat femoral arteries. In clinical practice, minor torsion can be tolerated, however, factors affecting patency such as tension, diameter disproportion, and tight closure can affect the final result of anastomosis. We observed that torsional force of the vessel is distributed along the artery to the weakest point.
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Affiliation(s)
- Murat Topalan
- Department of Plastic and Reconstructive Surgery, Istanbul University, Istanbul Medical Faculty, Istanbul, Turkey.
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Leung F, Zhu L, Ho H, Lu WW, Chow SP. Palmar plate fixation of AO type C2 fracture of distal radius using a locking compression plate--a biomechanical study in a cadaveric model. J Hand Surg Br 2003; 28:263-6. [PMID: 12809662 DOI: 10.1016/s0266-7681(03)00011-1] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The stability of palmar plate fixation using a locking compression T-plate was compared with that of a conventional palmar T-plate and a dorsal T-plate in a cadaveric model of an AO type C2 fracture of distal radius. The wrist axial load transmission through the radius was tested for each fixation. The results show that, under 100N axial load, the palmar locking compression T-plate restores stability comparable to that of the intact radius, and is superior to conventional palmar or dorsal T-plates.
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Affiliation(s)
- F Leung
- Department of Orthopaedic Surgery, Queen Mary Hospital, The University of Hong Kong, Hong Kong, People's Republic of China.
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Zhu L, Ho H, Lu W, Leung F, Chow SP. A cadaveric model for biomechanical study of fixation methods for AO type C2 fractures of distal radius: design and testing with dorsal plating fixation. Hand Surg 2002; 7:279-83. [PMID: 12596291 DOI: 10.1142/s0218810402001163] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2002] [Accepted: 09/12/2002] [Indexed: 11/18/2022]
Abstract
Fracture of the distal radius is a common injury. Functional recovery correlates well with restoration of anatomy and early motion. Various fixation methods have been proposed to achieve this. To evaluate the stability of different treatment options, a cadaveric model for biomechanical study of fixation methods for AO type C2 fracture of distal radius was designed and its efficacy assessed in the present experiment.
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Affiliation(s)
- Lijun Zhu
- Department of Orthopaedics and Traumatology, The First Military Medical University Nanfang Hospital, Guangzhou 510515 PR China
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Wang A, Chow SP. Vascularized peripheral nerve trunk autografted in the spinal cord: a new experimental model in adult rats. Chin J Traumatol 2001; 4:208-13. [PMID: 11835734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To investigate the effect of vascularized peripheral nerve trunk autografted in spinal cord. METHODS With modern microsurgical technique, vascularized peripheral median and ulnar nerve trunk autografted in the upper thoracic region of the spinal cord were established in 20 female adult rats. The origin and the termination of axons in the graft were studied by retrograde neuronal labeling with horseradish peroxidase (HRP). Cord, nerve grafts and some normal median an d ul nar nerves in the right upper limb were removed and sectioned for Bielschowsky's silver stain and haematoxylin and eosin (H&E) stain. Light and electron microscopic examination and electrophysiological examination were applied. RESULTS The grafts were innervated by many new fibers. Studies with HRP indicated that new axons in graft were originated from intrinsic cent ral nervous system (CNS) neurons with their cell bodies from brain stem to s acral segments of spinal cord. Other axons arose from dorsal root ganglia at the level of graft and at least 19 distal segments to them. Together with electron microscopy, electrophysiological examination, silver and H&E stain, the results demonstrated that vascularized peripheral nerve trunk grafted in spinal cord attracted many neurons to grow into the nerve grafts. CONCLUSIONS The findings implicate that CNS is able to regenerate much better in vascularized nerve autografted in spinal cord.
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Affiliation(s)
- A Wang
- Department of Orthopedic Surgery, Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, China
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Schneeberger AG, Ip WY, Poon TL, Chow SP. Open reduction and plate fixation of displaced AO type C3 fractures of the distal radius: restoration of articular congruity in eighteen cases. J Orthop Trauma 2001; 15:350-7. [PMID: 11433140 DOI: 10.1097/00005131-200106000-00008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the ability of open reduction and plate fixation to restore articular congruity in the treatment of fractures of the distal radius with intraarticular comminution and displacement. DESIGN Prospectively followed series. METHODS Eighteen consecutive fractures of the distal radius with intraarticular comminution and displacement were treated with open reduction and combined volar and dorsal plate fixation in thirteen, dorsal plate fixation in four, and volar plate fixation in one case. Kirschner wires were added in thirteen fractures and cancellous bone graft was used in four fractures. Articular congruity after a mean follow-up of twenty-three months was assessed using anteroposterior and lateral radiographs. RESULTS Articular congruity without a two millimeter or more intraarticular stepoff was found at follow-up in fifteen of eighteen cases, without a two millimeter or more gap in nine cases and without a two millimeter or more stepoff or gap in only eight cases. One reason for not having obtained articular congruity in some of the fractures was insufficient intraoperative visualization of the joint surface. Three reduced fractures redisplaced. The reason for loss of intraarticular reduction was considered insufficient stabilization of the distal fragments. In two of the three cases, it was thought that insertion of bone graft would have prevented the loss of reduction. CONCLUSIONS Articular incongruity after open reduction and plate fixation of comminuted fractures of the distal radius may occur more often than expected. The reduced fracture should be evaluated by intraoperative radiographs. If the reduced joint surface is not entirely visible on the radiographs because of implants or other reasons, oblique radiographs or fluoroscopy should be additionally used. Plate fixation alone does not always provide sufficient stability and cancellous bone graft should be added in cases of metaphyseal bone loss or for stabilization of multiple small articular fragments that cannot be fixed by screws or Kirschner wires.
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Affiliation(s)
- A G Schneeberger
- Department of Orthopaedic Surgery, Queen Mary Hospital, University of Hong Kong, Pokfulam, Hong Kong, China
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Chow SP, Furamachi K. Experimental study of multiple level compression of the spinal cord in the rat. J Orthop Surg (Hong Kong) 2001; 9:9-13. [PMID: 12468837 DOI: 10.1177/230949900100900103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A rat model study was performed to evaluate the effects of compression of the thoracic spinal cord. Dorsal screw compression of the thoracic spinal cord up to 50% canal diameter was created at T5 (Group A), T5 and T11 (Group B), and T5 and T8 (Group C). Clinical grading (Tarlov criteria), sensory evoked and motor evoked potentials, horse raddish peroxidase neural transport, and microangiography were studied. Single level compression had little effect. For double compression, there were marked detrimental effects both clinically and electrophysiologically, especially when the compression was close together. Neutral transport was affected in all groups, but the difference was not significant between them.
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Affiliation(s)
- S P Chow
- Department of Orthopaedic Surgery, The University of Hong Kong, Hong Kong
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Ip WY, Shibata T, Tang FH, Mak AF, Chow SP. Adhesion formation after nerve repair: an experimental study of early protected mobilization in the rabbit. J Hand Surg Br 2000; 25:582-4. [PMID: 11106524 DOI: 10.1054/jhsb.2000.0480] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The common peroneal nerve and its surrounding muscles were cut and repaired in 14 rabbits. The injured limb was then either immobilized for 3 weeks or passively mobilized within a "safety range" every day. At 3 weeks after operation, the "stretch test" and "peel test" showed no difference in the biomechanical features of the adhesions between the nerve repair and the surrounding soft tissues.
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Affiliation(s)
- W Y Ip
- Department of Orthopaedic Surgery, The University of Hong Kong, Hong Kong, PR China
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Leung F, Ozkan M, Chow SP. Conservative treatment of intra-articular fractures of the distal radius--factors affecting functional outcome. Hand Surg 2000; 5:145-53. [PMID: 11301509 DOI: 10.1142/s0218810400000338] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2000] [Accepted: 11/13/2000] [Indexed: 11/18/2022]
Abstract
One hundred and eleven intra-articular fractures of the distal radius in young adults that were conservatively treated were studied. At two years, 80% of fractures were rated as excellent or good by the modified Green and O'Brien scoring system. The rate of re-displacement within casts was 28%. Sixty five per cent of re-displaced fractures were treated with surgical fixation. Those re-displaced fractures treated with repeated manipulation had only 33% excellent or good result. Moreover, their initial alignment could not be preserved. Axial compression (>2 mm) and dorsal angulation (>15 degrees ) were directly related to worse functional outcome and diminished range of motion.
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Affiliation(s)
- F Leung
- The Department of Orthopaedic Surgery, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China
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28
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Abstract
Nm23 protein expression was analyzed by immunohistochemical staining using formalin-fixed, paraffin-embedded sections from 39 cases with osteosarcomas and compared with the histologic findings and early metastasis for the purpose of detecting nm23 expression in osteosarcoma and elucidating the clinical significance of its expression. Immunoreactivity of nm23 protein was detected in 48.7% of the total cases. There was no statistical difference between nm23 expression and early metastasis, but there was a trend for cases with nm23 expression to progress to early metastasis within 1 year after operation. The role of nm23 as a tumor metastasis suppressor in osteosarcomas appeared less prominent.
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Affiliation(s)
- W M Liao
- Department of Orthopedic Surgery, First Affiliated Hospital, Sun Yat Sen University of Medical Sciences, Guangzhou, China
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Li YW, Leong JC, Lu WW, Luk KD, Cheung KM, Chiu KY, Chow SP. A novel injectable bioactive bone cement for spinal surgery: a developmental and preclinical study. J Biomed Mater Res 2000; 52:164-70. [PMID: 10906688 DOI: 10.1002/1097-4636(200010)52:1<164::aid-jbm21>3.0.co;2-r] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The injection of bone cement by minimally invasive techniques for the treatment of vertebral body fractures or for stabilization of an osteoporotic vertebral body is regarded as promising in spinal surgery. The purpose of this study was to develop a novel injectable bioactive bone cement to address such concerns. The cement was composed mainly of strontium-containing hydroxyapatite (Sr-HA) filler and Bisphenol A Diglycidylether Dimethacrylate (D-GMA) resin. The Sr-HA filler was prepared by precipitation and calcination, then analyzed with Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) patterns. Samples of strontium-containing hydroxyapatite cement (SrHAC) were formed by a combination of powder filler and resin matrix, with the setting time and peak temperature recorded. Cell relative growth rate (RGR), Tetrazolium bromide (MTT), and haemolysis tests were used to detect initial in vitro biocompatibility of the new cement. In vitro spinal biomechanical testing and morphological observation after bone cement injection were performed on pig spines. Results indicate that the setting time and peak temperature of the cement was 15 min and 55 degrees C, respectively. Cytotoxicity of the cement was class 1 (no cytotoxicity) and haemolysis was 1% (no haemolysis). Stiffness after cement injection and fatigue loading were 112% and 95% of the intact bone, respectively, which is similar to that of natural bone. Radiopacity of SrHAC allowed easy radiographic imaging. The use of SrHAC cement is, thus, promising in spinal surgery.
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Affiliation(s)
- Y W Li
- Department of Orthopaedic Surgery, The University of Hong Kong, Hong Kong.
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Lu WW, Ip WY, Jing WM, Holmes AD, Chow SP. Biomechanical properties of thin skin flap after basic fibroblast growth factor (bFGF) administration. Br J Plast Surg 2000; 53:225-9. [PMID: 10738329 DOI: 10.1054/bjps.1999.3264] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study is designed to examine the effects of basic fibroblast growth factor (bFGF) administration on the biomechanical properties of thin skin flap healing. A total of 42 rats were used in this study, and skin flaps 10 cm long by 3 cm wide were raised in 28 rats. One injection of bFGF was applied at three different times (immediately postoperatively, and 24 h and 48 h postoperatively) between the flap and wound bed of 14 rats (the bFGF treated group), while the other 14 rats with flaps had the same tissue culture medium treatment but without bFGF (the untreated group). The remaining 14 rats without flaps constituted the control group (normal group). The rats were killed 10 days postoperatively, and 1. 0 cm x 6.0 cm sections of the skin flap taken for mechanical and histological testing. The load, deformation and tensile strength at failure were recorded. The average flap survival area in the bFGF treated group was 27 cm(2), significantly higher (P< 0.001) than that seen in the untreated group. The average elastic stiffness of the skin flap in the bFGF treated group was also observed to be higher than in the untreated group although this difference was not significant. The mean tensile strength of the bFGF treated group (61 N) was significantly higher than the untreated group (38 N, P< 0.01) however. Despite this, the tensile strengths at failure of both of these groups were found to be significantly lower than that of normal skin (101 N, P< 0.01). A relaxation in load of about 8% was seen in specimens from the normal group and the bFGF treated group, while the untreated group showed a relaxation of about 15%.
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Affiliation(s)
- W W Lu
- Department of Orthopaedic Surgery, The University of Hong Kong, Hong Kong, China
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Chow SP, Ip WY, Poon TL. Comminuted Intra-Articular Fracture of the Distal Radius - The Technique of Open Reduction and Internal Fixation With Plating. Hand Surg 1999; 4:175-180. [PMID: 11089176 DOI: 10.1142/s0218810499000381] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/1999] [Accepted: 10/20/1999] [Indexed: 11/18/2022]
Abstract
The technical details of open reduction and internal fixation with double plating for a patient with comminuted intra-articular fractures of the distal radius were described. The vital steps included the exposure, initial dorsal reduction, ventral reduction and fixation, checking of reduction, return to dorsal surface with final reduction and X-ray check, and wound closure. Special attention and other technical tips were also highlighted, and hopefully will shorten the learning curve of others who would like to use this rather demanding technique for their patients.
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Affiliation(s)
- SP Chow
- Department of Orthopaedic Surgery, Queen Mary Hospital, Hong Kong, ROC
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Abstract
The purpose of this study was to propose a standard protocol for administering the Moberg pickup test. One hundred subjects (53 male and 47 female subjects, aged 11 to 77 years) volunteered. A wide variety of occupations were represented. No subjects had a history of upper extremity dysfunction. The materials and the testing procedures were clearly described to the subjects. Both hand dominance and gender difference were found to have significant effects on test performance. Norms were established for dominant/nondominant hands and for male/female subjects. Standard scores were calculated and used for comparison. The inter-rater reliability of the test was also determined. Administered with a standard protocol, the Moberg pickup test is a valuable test of functional sensibility. It is simple and quick to administer, easy to replicate, and inexpensive to acquire.
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Affiliation(s)
- C L Ng
- Leslie R Peterson Rehabilitation Centre, Worker's Compensation Board of British Columbia, Richmond, Canada
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Roure P, Ip WY, Lu W, Chow SP, Gogolewski S. Intramedullary fixation by resorbable rods in a comminuted phalangeal fracture model. A biomechanical study. J Hand Surg Br 1999; 24:476-81. [PMID: 10473162 DOI: 10.1054/jhsb.1999.0167] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The mechanical rigidity of three different methods of resorbable intramedullary fixation (bone peg, and polyglycolide rods with and without interlocking) was assessed in a comminuted phalangeal fracture model and the results compared with two commonly used internal fixation devices (lateral plate, crossed K-wires) in a cadaver model. Each fixation technique was tested for its biomechanical strength in apex palmar bending, compression and torsion. Failure testing for the three resorbable methods was also done. The results showed that lateral plating provided the best rigidity in apex palmar bending and torsion, followed by intramedullary bone peg fixation. All resorbable intramedullary fixations had rigidity that was at least the same as crossed K-wires. For the torque test, polyglycolide rods with interlocking provided better rigidity than without interlocking. There was no significant difference between the different methods in the compression test, except that the intramedullary bone peg was significantly stiffer than K-wires.
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Affiliation(s)
- P Roure
- Department of Orthopaedic Surgery, Queen Mary Hospital, University of Hong Kong, Hong Kong
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Liao W, Chiu KY, Han S, Li F, Qiu J, Chow SP. Preliminary observation on the correlation between nm23 expression and Ki-67 antigen with early metastasis of human osteosarcoma. Chin Med J (Engl) 1998; 111:813-7. [PMID: 11155673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
OBJECTIVES To detect the nm23 expression in osteosarcoma, analyze the correlation between nm23 expression and early metastasis and to study the relation between nm23 expression with tumor differentiation and cell proliferation, as defined by Ki-67 labeling. METHODS nm23 oncoprotein expression was measured by immunohistochemical staining using formalin fixed, paraffin embedded sections of 39 surgically resected osteosarcomas and was compared with Ki-67 expression, histological findings and early metastasis. In each sample, the grading of immunoreactivity was recorded as 0, 1+, 2+ according to the percentage of nm23 and Ki-67 labeling cells respectively. RESULTS The cases with more than 25% positive immunoreactivity of nm23 protein were detected in 48.7% of the total cases. There was no statistical difference between nm23 expression and early metastasis, but the cases with nm23 expression appeared to have a trend to get early metastasis. nm23 expression was significantly correlated with Ki-67 expression, which was associated with differentiation of the tumor cells. CONCLUSION The role of nm23 as a tumor metastasis suppressor in osteosarcoma is less prominent. Both nm23 and Ki-67 may help predict the possibility of early metastasis in human osteosarcomas.
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Affiliation(s)
- W Liao
- Department of Orthopedic Surgery, First Affiliated Hospital, Sun Yat-sen University of Medical Sciences (SUMS), Guangzhou 510080, China
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35
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Abstract
The mechanical rigidity of five different methods of pin fixation in two proximal phalangeal fracture models was studied and absorbable implants were compared with metallic implants in a biomechanical cadaver study. Thirty phalanges were tested in apex palmar bending, compression and torsion. Results showed that rigidity of absorbable implants was comparable with metallic implants, except in torsion.
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Affiliation(s)
- F Fitoussi
- Department of Orthopaedic Surgery, University Hong Kong, Queen Mary Hospital, Hong Kong
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36
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Abstract
Thirty-four displaced intra-articular fractures of the distal aspect of the radius in thirty-four patients were treated with open reduction and internal fixation with plates and screws. Although there was a high rate of complications (nine [26 per cent] of thirty-four fractures), twenty-eight patients (82 per cent) had a good or excellent result according to the system of Gartland and Werley and twenty patients (59 per cent) had a good or excellent result according to the modified system of Green and O'Brien at the most recent evaluation. Immediately postoperatively, the articular surface of the distal aspect of the radius was restored to a mean of 2 degrees of volar tilt and 20 degrees of radial angulation and radial length was improved by a mean of ten millimeters compared with the preoperative length. The articular surface was restored to congruity or to at most one millimeter of step-off in twenty-six patients (76 per cent). By the time of the most recent evaluation, the initial postoperative alignment had changed markedly in three patients (9 per cent) and degenerative osteoarthrosis (grade II or III) had developed in six patients (18 per cent). We considered that the initial postoperative alignment had changed markedly when the articular surface was displaced by two millimeters or more, when the extra-articular alignment had changed by more than 10 degrees of radial tilt, or when there was more than five millimeters of radial shortening. The potential for restoration of normal alignment and the stability of the fixation are the main advantages of internal fixation with plates. Restoration of congruity to the joint was the major difficulty in this group of patients.
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Affiliation(s)
- F Fitoussi
- Department of Orthopaedic Surgery, Queen Mary Hospital, The University of Hong Kong.
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37
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Chow SP, Dixon AS. Medical education at the University of Hong Kong: changes and challenges. Chin Med J (Engl) 1997; 110:403-7. [PMID: 9594238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
- S P Chow
- Faculty of Medicine, University of Hong Kong, Hong Kong
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Abstract
We report a prospective study of dynamic splintage following extensor tendon repair. Eighty-four patients with 101 extensor tendon injuries were studied. Using Dargan's evaluation system, there were 97% excellent results for the thumb and 93% excellent and good results for the fingers. The average total active motions were 107 degrees for thumbs and 245 degrees for fingers. Over 80% of patients regained good power grip. Patients with associated digital fractures or with ragged lacerations had poorer results. Overall, we found that dynamic splintage was a satisfactory method after extensor repair.
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Affiliation(s)
- W Y Ip
- Department of Orthopaedic Surgery, University of Hong Kong
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39
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Abstract
The mechanical rigidity obtained by external fixation in a comminuted phalangeal fracture model was assessed and the results compared with two other types of internal fixation commonly used (lateral plate and crossed Kirschner wires) in a biomechanical cadaver study. Each fixation technique was tested in apex palmar bending, compression and torsion. The results showed that lateral plating provided the best rigidity in apex palmar bending and compression and that external fixation and Kirschner wires showed the same mechanical properties. For the torque test, external fixation provided the best rigidity.
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Affiliation(s)
- F Fitoussi
- Department of Orthopaedic Surgery, University of Hong Kong, Queen Mary Hospital, Hong Kong
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40
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Abstract
The rigidities of five fixation methods have been studied with a comminuted phalangeal fracture model. Mechanical testing of compression, bending and torsion were performed for each fixation. Lateral plating with six screws seems to provide the most rigid fixation. If such lateral plating is not practicable, the four-Kirschner wire method would be a satisfactory alternative.
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Affiliation(s)
- W W Lu
- Department of Orthopaedic Surgery, University of Hong Kong, Hong Kong
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41
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Abstract
A prospective study was made of 1500 elderly patients who suffered from acute hip fractures from 1986 to 1990. There were 36 per cent more fractures in the 6 colder months from November to April than in the rest of the year (P < 0.001). A strong correlation between the monthly adjusted fracture rate and the average lowest ambient temperature was also observed (P < 0.001). The fractures occurred in the older and less active patients during the 6 colder months. More importantly, they needed to wait longer for the operation during this 'high' season. This might be responsible for the higher medical complication rate after the operation. Better health care planning to help with the increased patient load in the 'high' season is essential to reduce the waiting time for the operation and the postoperative medical complication rate.
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Affiliation(s)
- K Y Chiu
- Department of Orthopaedic Surgery, University of Hong Kong
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42
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Abstract
A prospective study of 1129 patients with 1358 digital fractures of the hand was carried out between March 1984 and March 1994; of these, 924 fulfilled the criteria for inclusion. Functionally stable fractures with acceptable alignment were managed with immediate active mobilization. Unstable fractures, or fractures with unacceptable alignment, were openly reduced and fixed internally so that active mobilization could begin immediately after operation. The function results using various systems of evaluation were excellent or good in over 90 per cent of the fractured thumbs, and excellent or good in 58.7 per cent to 76.5 per cent of the fingers. Patients who did not require surgery did much better than those in the operated group. Comminuted, open and multiple fractures proved to be of poor prognostic value. However, rigid fixation was statistically significant in influencing the outcome.
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Affiliation(s)
- W Y Ip
- Department of Orthopaedic Surgery, University of Hong Kong
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Ochi M, Kwong WH, Kimori K, Takemoto S, Chow SP, Ikuta Y. Delay of the denervation process in skeletal muscle by sensory ganglion graft and its clinical application. Plast Reconstr Surg 1996; 97:577-86. [PMID: 8596789 DOI: 10.1097/00006534-199603000-00014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We examined the effects of dorsal root ganglion isografts on the denervation process of skeletal muscle. A segment of sciatic nerve was removed from each of 25 inbred Wistar-Kyoto rats. Fifteen were set aside as controls. In the remaining 10 rats, isogeneic cervical dorsal root ganglia were grafted to the severed distal stump of the common peroneal nerve. Between day 72 and day 286 postoperatively, both controls and recipients were killed after twitch and tetanic tension recording of the extensor digitorum longus was performed. The wet muscle weight and the twitch and tetanic tensions of the denervated extensor digitorum longus in the graft group were significantly greater than those in the control group. The mean area of the denervated tibialis anterior muscle fibers in the graft group also was significantly larger than that in the control group. In electron and light microscopic images, nerve cells along the periphery of each dorsal root ganglion were found surviving with regenerating axons throughout the experimental period. Numerous myelinated axons were observed in the common peroneal nerve of the graft group, and there were significantly more axonal branches in the extensor digitorum longus of the graft group than in the extensor digitorum longus of the control group. Thus sensory nerve fibers from the grafted dorsal root ganglia had certain beneficial effects to slow the denervation process, presumably secreting trophic factors into the denervated muscle. Clinically, we have transferred avulsed dorsal root ganglia in cases of total brachial plexus avulsion directly into denervated skeletal muscle. This procedure, accompanied by nerve crossing procedures, will probably keep denervated skeletal muscle in a better condition until regenerating motor axons from the repair site reach their target muscle.
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Affiliation(s)
- M Ochi
- Department of Orthopaedic Surgery, Hiroshima University School of Medicine, Japan
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44
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Abstract
In a review of 52 consecutive intra-articular fractures of the wrist (mean age 41 years), 18 developed one of five carpal malalignment patterns. Seven patients developed a volar intercalated collapse pattern. Although showing some loss of motion and/or grip strength, this group remains relatively pain free on follow-up. Patients who developed dorsal translation (six cases) or a dorsal intercalated collapse pattern (one case) were the most symptomatic, with loss of grip strength, decreased range of motion and pain being prevalent.
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Affiliation(s)
- S J O'Flanagan
- Department of Orthopaedic Surgery, University of Hong Kong
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45
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Abstract
Closed avulsion of both flexor digitorum profundus and superficialis from the same finger is rare. Only ten cases have been described in the literature. The majority were treated with a two stage reconstruction of the flexor digitorum profundus. We describe a case in which primary repair of both tendons was performed.
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Affiliation(s)
- K M Cheung
- Department of Orthopaedic Surgery, University of Hong Kong, Queen Mary Hospital
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46
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Chiu KY, Pun WK, Luk KD, Chow SP. Cancellous screw fixation for subcapital femoral neck fractures. J R Coll Surg Edinb 1994; 39:130-2. [PMID: 7520071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Experience in treating 80 subcapital femoral neck fractures by AO/ASIF cancellous screws is reported. Immediate full-weight bearing was allowed routinely. The mean follow-up was 28 months. Non-union occurred in 2% and late segmental collapse in 12% of patients with undisplaced fractures. Non-union occurred in 16.7% and late segmental collapse in 30% of patients for displaced fractures. Regression of screws occurred in 30% of patients, all of which were detected within the first month after the operation. It was associated with a significantly higher risk of non-union and late segmental collapse for both undisplaced (P < 0.01) and displaced (P < 0.001) fractures.
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Affiliation(s)
- K Y Chiu
- Department of Orthopaedic Surgery, University of Hong Kong, Queen Mary Hospital
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47
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Leong JC, Chow SP, Yau AC. Titanium-mesh block replacement of the intervertebral disk. Clin Orthop Relat Res 1994:52-63. [PMID: 8131356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A prospective clinical trial was conducted involving patients with prolapsed lumbar intervertebral disk proven myelographically, who had anterior diskectomy and disk replacement with a titanium-mesh block implant. A pilot study was done in 1971 on six patients. In this trial, 28 patients were operated on with informed consent. Twenty-three had a minimum of five years' follow-up study. There were 14 men and boys, and nine women and girls. The average follow-up period was eight years and four months (range, five to 12 years three months). The average age at operation was 36 years four months (range, 13-66 years). Symptomatic improvement were divided into three groups. Sixteen patients were in Group 1, three in Group 2, and three in Group 3. Flexion-extension radiographs showed 14 patients with no movement between the vertebral bodies adjacent to the operated disk, five with minimal movement, and four with definite movement. At the implant-bone interface, no radiolucent zone was seen in 18 patients, and a definite radiolucent zone was seen in five. Twenty implants were intact, three implants had developed a crack, and three were deformed. There were no complications. The titanium-mesh block implant is an effective substitute for autogenous bone grafting in interbody fusion.
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Affiliation(s)
- J C Leong
- Department of Orthopaedic Surgery, University of Hong Kong, Queen Mary Hospital
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48
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Abstract
72 fingers with divided digital nerves on one side alone had their nerves repaired and the sensory recovery assessed at different intervals of up to 2 years. Another 36 fingers with similar digital nerve injuries had their divided nerves left unrepaired and sensory recovery similarly assessed for comparison. In the "repaired" group, the result continued to improve and by 2 years, 90% reached S3+ or above. In the "unrepaired" group, improvement plateaued after 6 months, and at 2 years only 6% reached S3+ or above, although all had regained some protective sensibility.
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Affiliation(s)
- S P Chow
- Department of Orthopaedic Surgery, University of Hong Kong
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49
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Abstract
One hundred and twenty patients with acute hip fractures treated operatively were randomized into two groups. In the 'drape' group (n = 65) the operation site was covered with plastic adhesive drape after preparation. In the 'no drape' group (n = 55) the operation site was left uncovered. The two groups were otherwise matched. Swabs for culture were taken from skin adjacent to the wound before closure. The drape group had four positive wound swabs. There was only one positive wound swab for the no-drape group. There was no difference in the post-operative wound infection rates.
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Affiliation(s)
- K Y Chiu
- Department of Orthopaedic Surgery, Queen Mary Hospital, University of Hong Kong
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Abstract
A skin flap in the anterior abdominal wall of the S-D rat was designed so that it was supplied by the superficial epigastric branch of the femoral artery on the right side. Venous drainage was effected through one of five designs: (1) the superficial epigastric vein on the same side, (2) the lateral abdominal vein on the same side, (3) the lateral abdominal vein on the opposite side, (4) the superficial epigastric vein on the opposite side, or (5) a combination of the latter three. Seventy-seven rats were available for final analysis. The surviving percentage area of the flap was found to improve with increased venous drainage and when the arterial blood had to traverse the flap to reach the diagonally situated draining vein. The use of venae commitante as the draining vein is not satisfactory.
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Affiliation(s)
- S P Chow
- Department of Orthopaedic Surgery, University of Hong Kong
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