CAGE CULTURE OF SOUTH AMERICAN CATFISH (RHAMDIA SAPO) PRELIMINARY RESULTS IN THE SALTO GRANDE RESERVOIR (ARGENTINA) LAURA M. LUCHINI and ROLANDO QUIROS Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP) C.C. 175, 7600 Mar Del Plata. Argentina The first experimental cage culture of South American catfish (Rhamdia sapo) was carried out in the Salto Grande
ReviewcourseinhandsurgeryThe practice of Hand Surgery continues to evolve in the light of new research and technology. It still is of specialinterest to not only to full time Hand Surgeons but also toOrthopaedic and Plastic surgeons as well. This is especiallyso in areas of the distal radius and carpus. In the interestof continuity, we in the organising committee have decidedto look further distally from last year into the problems ofthe carpus. Carpal pathology and injuries continue to benot well understood and there is diversity of management as a result. This meeting, though short, hopes to look intosome of these problems and discuss some of the currentthinking and management of these problems.
As usual, the first part of the meeting will be the HandReview Course. This component is organised annually bythe Society as part of its commitment to the teaching andtraining of advanced trainees in the subject of Hand Surgery.
It continues to be relevant for advance trainees in HandSurgery, Orthopaedics and Plastic Surgery. In addition, therewill be the free paper session for trainees to present theirwork as part of the Society’s Scientific Meeting.
In all we hope that the meeting will prove fruitful andenjoyable for all its participants.
SSHS Executive Committee
SSHS Organising Committee
Tel :(65)6321-4588 • Fax: (65)6227-3573 Annual Review Course in Hand SurgeryVenue: PGMI, Singapore General Hospital 08:00 am REGISTRATION
Traumatic Hand / Wrist Injuries
Degenerative Conditions of the Hands / Wrist
Venue: PGMI, Singapore General Hospital 08:00 am REGISTRATION
Symposium I : Acute Carpal Injuries
Symposium II : Carpal Instability
Symposium III : Traumatic Arthritis of Wrist
Round Table Discussion : Chairman: Dr Low C O
Panelists : Dr Ho P C, A/Prof Lim B H, Dr Yong F C,
Dr Low C K
- Proximal Fracture Scaphoid AVN- Kenbocks Disease- SNAC wrist- SLAC wrist TEA
Free Paper Presentation
Occupational Therapy Workshop
(Venue : Experimental Surgery
Banquet at Grand Copthorne Waterfront Singapore
Workshop on Carpal Approach and Fixation
Jointly organised by Singapore Society for Hand Surgery &
Department of Orthopaedic Surgery, Changi General Hospital
Venue: Changi General Hospital, OT Conference Room
Facilitators: Dr Low C O, Dr Looi K P, Dr Winston Chew, Dr Low C K, Dr Chan B K) A) FIXATION WORKSHOP (Demonstration by Dr Ho P C)
Percutaneous Scaphoid Fixation – Volar and Dorsal
a) Percutaneous – Fixation of Scaphoid
b) Arthroscopic Scaphoid Fixation
B) CADAVERIC DISSECTION
Surgical Approach to Scaphoid
a) Dorsal Approach + Vascular Bone Graft (Dr Looi K P)
b) Volar Approach (Dr Winston Chew)
Chairman : Dr Tan Soo Heong
Carpal Tunnel Release Using a Short Palmar Dr Michael SoonIncision Syndactyly Release Without Skin Grafts – for Thumb Duplication Reconstructionin the Adults Tensile Strength of Tendons; an In-VitroStudy Post-Operative Mobilization of the Hand– A Clinical Series Type C1-C3 Dorsal and Volar DisplacedDistal Radius Fractures with Volar Plateand Dorsal Intrafocal Pinning Strain Rate Effect on the Tensile Properties Interpositional Subcutaneous Tissue Flap For Extensor
Dr Tay Shian-Chao, Dr Tian Ho-Heng, Dr Teoh Lam-Chuan,
Dr Yong Fok-Chuan, Dr Tan Soo-Heong,
Department of Hand Surgery, Singapore General Hospital
Session Presenter : Dr Tay Shian Chao
Extensor tendon adhesion is a cause of restricted motion in internalfixation of phalangeal fractures. Extensor tenolysis together with implantremoval is often unsuccessful, due to recurrence of the extensor tendonadhesion. We present our technique of interpositional subcutaneous tissueflap for extensor tenolysis.
Paper Fifteen patients aged between 21 and 55 years, had extensor tendon adhesion and restricted joint motion after internal fixation of phalangealfractures. They underwent tenolysis and implant removal 6 months afterthe internal fixation and rehabilitation. From a midline incision, twosubcutaneous tissue flaps, based on the dorsal communicating vessels, Free were harvested from both sides of the corresponding phalanx. The flaps were sutured together in the midline, interposing between the extensortendon and the bone. A vascularized gliding bed between the extensortendon and the bone is thus created. Postoperative routine therapy wasstarted immediately, and the finger was splinted in extension in betweenthe mobilization sessions. Results were evaluated using the Total ActiveMotion (TAM) and Digital Functional Assessment systems (DFAS).
The preoperative TAM range was from 15 to 190 degrees. In theimmediate post-tenolysis period, all patients had improvement in theirTAM, with an absolute range of 65 to 245 degrees (improvement between5 to 155 degrees). At the final review 4 to 6 months post-operatively, 4patients had no further gains in their TAM, 6 improved by a further 15-65 degrees, and 5 lost between 5-47 degrees of their initial gains. 13 outof the 15 patients managed to maintain at least 78% of the initial gains.
Using the Digital Functional Assessment, pre-tenolysis, 8 patients hadpoor digital function, 5 fair, and 2 good. At the final review after tenolysis,2 patients remained with poor functional scores. The rest had improvedto either a fair or good grade, and 4 managed to achieve excellentfunction. The procedure was well tolerated and there were nocomplications.
Both physical barriers and chemical mediators have been used in anattempt to decrease the formation of adhesions after tenolysis. However,these methods are not without complications. The interpositionalvascularized subcutaneous tissue flap is safe and effective in reducingthe re-adherence of the tendon to the underlying bone after the extensortenolysis.
Carpal Tunnel Release Using A Short Palmar Incision – A
Retrospective Review Of 24 Cases
Dr Michael Soon, A/Prof Lim Beng Hai
Dr Michael Soon
Carpal tunnel release is the most common surgical procedure performed in the hand and wrist. There are many methods for releasing the transverse carpal ligament. The 2 main methods are conventional open and endoscopic carpal tunnel release, both with its advantages and potential complications. The method which we describe is a carpal tunnel release using a short mid palmar incision (which was first reported by James Strickland in 1996), and seeks to combine the simplicity and safety of conventional open carpal tunnel release, with the advantages of reduced tissue trauma and postoperative morbidity of endoscopic relase. A mid-palm incision allows direct visualization of the neurovascular structures and the use of the carpal tunnel tome preserved all the same structures that the endoscopic method preserves. Our clinical experience with this device is reported in this retrospective study of 24 cases of carpal tunnel release, and this procedure’s efficacy and postoperative recovery is comparable to that achieved by endoscopic Syndactyly Release Without Skin Grafts – The Dorsal
Pentagonal Island Flap
Dr Jonathan Lee Yi-Liang, Dr Teoh Lam-Chuan
Department of Hand Surgery, Singapore General Hospital
Dr Jonathan Lee Yi-Liang
Session There is a myriad of techniques described for the correction of syndactyly. However, most well accepted methods of correction stillresult in skin deficiency, most evident in the area of the finger bases.
Presently, full thickness skin grafts are used to resurface these deficits,which can result in many undesirable sequelae. We present ourexperience with the pentagonal dorsal metacarpal island flap, a Paper technique that now allows us to perform routine syndactylysis without We have used this technique for all our syndactyly reconstructions overthe past 2 years. A total of 12 patients with 22 webs releases weredone in this fashion. Their ages range from 8 months to 24 years. There Free were 8 simple complete, 1 simple incomplete, 1 complex and 11 syndromic syndactyly webs. In 2 cases, this technique was used forsecondary correction of web creep.
The dorsal metacarpal island flap is raised based on the perforatorsfrom the the dorsal metacarpal arteries. Dorsal and volar zigzag incisionscreate triangular flaps for finger resurfacing. Thinning of the fattytissue around each neurovascular bundle is done to ease closure. Thepentagonal flap is advanced to reconstitute the web, the donor site isclosed in a VY fashion and all incisions are closed directly.
All syndactyly webs were successfully reconstructed with no flap losses.
Direct closure was achieved in all cases. Primary healing occurred in allcases within 2 weeks. The follow-up at 6 to 24 months have been veryfavourable. There were 2 cases of early hypertrophic scarring whichsettled with conservative scar management.
Direct closure of syndactyly correction has been facilitated by our useof the dorsal pentagonal island flap. This obviates the use of skingrafts thus reducing operative time and reduces the likelihood of poortake and late contractures. Because flaps grow with the child, we expectthat the incidence of web creep will also be reduced. This reliable flapis suitable for all types of syndactyly and has given us very favourablefunctional and aesthetic results.
Subfascial Transposition Of The Ulnar Nerve
Dr Andrew Chin Yuan-Hui, Dr Tan Soo Heong
Department of Hand Surgery, Singapore General Hospital
Dr Andrew Chin Yuan Hui
Anterior transposition of the ulnar nerve is a surgical technique used in treatment of patients with Cubital Tunnel Syndrome of whichsubfascial transposition is a variation. This study aims to determine theoutcome of the patients who have undergone this new procedure inour department.
8 patients (6 men and 2 women) underwent subfascial transpositionbetween 1995 and 2001with follow up period ranging 6 months to 7years. Age at the time of operation ranges from 39 to 69 years (average 52 years). Preoperative grading of severity was based on Dellon’sclassification and postoperative outcome assessment was based onmodified Bishop’s rating.
All were graded as severe preoperatively with clinical evidence ofintrinsic wasting and weakness in grip strength. 8 patients underwent postoperative follow-up at the time of study. All had improvement (6excellent and 2 good, based on modified Bishop’s rating). All of themwere mobilized within the 1st week postop and all were back at workby the 5th week postop.
Subfascial transposition is similar to other variations of transposition interms of the nerve exposure and release from its native course at theelbow region. The only unique modification is that the transposednerve lies on the new bed, which is the flexor-pronator muscle groupand is held in place by the creation of the fascia flap derived from thesame muscle group. As a result, soft tissue dissection is kept to aminimum, translating to less peri-operative morbidity, reduced risk ofelbow flexion contracture, earlier mobilization and shorter recoveryperiod. The broad fascia flap prevents subluxation of the nerve back tothe retrocondylar groove and minimizes the potential of new site ofnerve compression.
Subfascial transposition is a good and effective technique for treatingpatients with Cubital Tunnel Syndrome. The technique is simple and itoffers promising results with minimal morbidity.
A New Method Of Corrective Osteotomy For Thumb
Duplication Reconstruction In The Adults
Dr Tan Ying-Chien, Dr Yong Fok-Chuan, Dr Teoh Lam-Chuan
Department of Hand Surgery, Singapore General Hospital
Dr Tan Ying-Chien
Session Due to socio-cultural reasons, some thumb duplication present late for correction. The reconstruction technique in the infant is well established.
The approach to the soft tissue correction is similar in both infant and adult.
However the bone and joint correction in the adult is difficult. The currentapproach in reconstruction may involve fusion of a previously mobilemetacarpophalangeal joint (MCPJ).
Paper We are proposing an improved technique of osteotomy that will favourably correct the severe MCPJ deviation and preserve motion. The techniqueinvolves an oblique metacarpal condylar osteotomy. In MCPJ deviation of30º or less, a closing wedge osteotomy is recommended. Deviation of morethan 30º, the osteotomised weged is reversed and used as a bone graft toenhance the correction angle to (30º x 2) = 60º. This improved osteotomy Free has the advantage of allowing adequate collateral ligament repair, preservation of vascularity to the metacarpal condyle, and easier approachto internal fixation of the osteotomy.
Seven adult patients with severely deviated thumb duplication had thismethod of osteotomy in the reconstruction. The osteotomy site united within6 weeks. The corrected MCPJ’s were stable and the alignment of themetacarpal to the phalanges was normal. The MCPJ motion recovered to arange of 20º to 60º and the interphalangeal joints recovered to a range of30º to 100º. MCPJ motion in a few patients was better than the pre-operativemeasurement. All patients recovered normal functional use of their thumbsand returned to their previous vocation. All of them were satisfied with thecorrected thumb.
While the reconstruction technique in the infant is well established, thesame cannot be said of reconstruction in adults. The reconstruction is difficult,and the current approach often involve fusion of a previously mobilemetacarpophalangeal joint (MCPJ), with unpredictable and unsatisfactoryresults. We are proposing an improved technique of osteotomy that willfavorably correct the severe MCPJ deviation and preserve motion. Thetechnique involves an oblique metacarpal condylar osteotomy which can beclosed or reversed depending on the angle of deviation of the MCPJ. It hasthe advantage of allowing adequate collateral ligament repair, preservationof vascularity to the distal metacarpal condyle as well as facilitate easierinternal fixation of the osteotomy. Seven adult patients underwent thistechnique of reconstruction. The osteotomy site united within 6 weeks.
The MCPJs were stable with good alignment. There was also good recoveryof the MCPJ and interphalangeal joint range of motion.
The Effect Of Needle Perforations On The Tensile Strength
Of Tendons; An In-vitro Study
A/Prof Chou Siaw Meng, Dr Esmond Yeoh, Mr Ng Boon Ho,
A/Prof Lim BH, Dr Alphonsus Chong
School of Mechanical and Production Engineering
National Technological University, Dept of Hand &
Reconstructive Microsurgery, National University Hospital
Mr Esmond SH Yeoh
The effect of corticosteroid injections on tendon has been studied withvarious conflicting results. Injection of tendons often involvedperforation of the tendon substance but no study has been done tostudy this effect ie. if perforations per se weakens the tendon. 3perforations were made each on chicken tendons with 19G, 23G and 27G needles. Only the large 19G needle showed significant effect; with26% of samples failing at the puncture site and showing lower loadsto failure.
The effect of corticosteroid injections on tendon has been studied with various conflicting results. Injection of tendons often involvedperforation of the tendon substance but no study has been done tostudy this effect ie. if perforations per se weakens the tendon.
3 perforations were made each on chicken tendons with 19G, 23G and27G needles. Only the large 19G needle showed significant effect; with26% of samples failing at the puncture site and showing lower loadsto failure. All other groups of needle perforated tendons showed nosignificant difference from control.
Rhomboid Rotational Osteotomy For Metacarpal Malunion
Dr Benjamin Tow Phak Boon, Dr Yong Fok-Chuan,
Dr Teoh Lam-Chuan
Department of Hand Surgery, Singapore General Hospital
Dr Benjamin Tow Phak Boon
Session Fractures of the metacarpals can lead to severe malunion and shortening.
Conventional methods of correction include the technique of opening or closing wedge osteotomy. This procedure results in changes in the length of the bone and may require a second operative site for harvesting autologous bone graft. We present the method rhomboid Paper rotational osteotomy which is a single step procedure which corrects dorsal angulation without changing the length of the bone significantly.
A 20-year-old male with malunion of the 4th and 5th metacarpal shafts, with pain on grasp and weakness, was treated by this technique. Post- Free operatively he had no pain on grasp and improved grip strength.
Continuous Local Anaesthesia In Post-Operative Mobilization
Of The Hand - A Clinical Series
Dr Yeong Pin Peng, Dr CK Low, Ms Chloe Seow,
Prof RWH Pho
Dr Yeong Pin Peng
Pain is a major inhibitory factor for early active mobilization in complex hand injuries, often leading to poor outcome. We studied the effects of sustained local anaesthesia of the hand to improve post operative mobilization. A preliminary in-vivo animal study performed on rat sciatic nerves has shown that repeated bupivacaine use does not lead Paper to peripheral nerve damage. 16 motived patients with 20 injured digits were evaluated. Small epidural catheters were placed adjacent to the peripheral nerves providing sensation to the involved part of the hand under direct vision in the distal forearm. Repeated doses of 0.5% Free bupivacaine were then administered during mobilization therapy to relieve pain. 16 out of 20 digits (80%) recorded significantly increased range of motion (> 30∞ increase in active range of motion) after theuse of bupivacaine. After stratifying the cases according to the severity of original injury, the cases that failed to improve had severe injuries from the start. Complications were relatively few and were easily resolved as the catheters were distal, superficial and easily accessible.
We believe that this is an effective, specific and safe method of providing sustained post operative anaesthesia for rehabilitation. Compared to conventional brachial plexus block, this method does not paralyse the forearm muscles, yet offers selective distal sensory blockade. It has been incorporated into our regular clinical use.
A New Technique For DRUJ Reconstruction
Dr S.S. Sathappan, A/Prof Lim Beng Hai
Dept of Orthopaedics, NUH, Dept of Hand & Reconstructive
Dr SS Sathappan
Session There have been many controversies concerning the anatomical structure of the distal radio-ulnar joint (DRUJ). But recent reports (Ishii et al1998) have shown that the DRUJ consists of 4 ligaments. Stabilizingprocedures mainly address the dorsal instability. This is contrary to theanatomical configuration of the DRUJ.
We have done cadaveric studies to describe the intricate anatomy of Paper the DRUJ, which consists of superficial and deep ligaments for both dorsal and volar aspects. There is also controversy on the relativetautness of the palmar and dorsal ligaments. We have shown via ourcadaveric studies that the ligaments work in concert.
In view of our cadaveric work, reconstructing all 4 ligaments would Free therefore be the optimum surgical treatment. A new technique of DRUJ stabilization is described, using toe extensor tendon, which re-establishes the tension and length of all four distal radial ulnarligaments.
Prospective study of patients with DRUJ instability who underwent the“four-ligament” reconstruction is being conducted. Early results showedthat the grip strength had improved with good pronation and supinationmovements.
The “four-ligament” reconstruction of the volar and dorsal deep andsuperficial distal radial ulnar ligaments is an effective procedure forDRUJ instability since it addresses the underlying anatomical andbiomechanical disruption of the DRUJ.
Surgical Fixation Of Intra-Articular Ao Type C1-C3 Dorsal
And Volar Displaced Distal Radius Fractures With Volar Plate
And Dorsal Intrafocal Pinning
Ganesan Naidu, Winston Chew, Chee Kwang Low
Dept. of Orthopaedic Surgery,Tan Tock Seng Hospital,
Dr Ganesan Naidu
Unstable intra-articular distal radius fractures are common and frequentlychallenge the skill of the orthopaedic surgeon. Surgical fixation should besimple,easily mastered, have good functional outcome and yet aim for nearanatomical reduction in order to minimise the risk of post-traumaticosteoarthritis. There is no concensus on the optimal form of treatment. Themore popular method of external fixation has its inherent problems of pintract infection, loss of reduction and digital stiffness. Dorsal plating is associated with extensor tendon dysfunction and possible rupture. Volarplating is reserved for Smith type fractures. Combined volar and dorsalapproach has been advocated by some authors, but it involves relativelyextensive dissection with its associated problems. We have used a combinationof volar plating and dorsal/lateral intrafocal pinning to treat both volar anddorsal displaced intra-articular fractures with outcomes which are favourable 22 consecutive patients underwent this procedure between Oct. 2000 andNovember 2001. The distal extension of the Henry’s approach was utilised forexposure. We used the AO oblique and T plate for volar fixation and 1.6 mmK wires for dorsal pinning at the 1-2,2-3 and 4-5 intercompartmental regionsusing Kapandji’s intrafocal technique. All cases were done with fluoroscopicguidance. Immediate finger motion and early postoperative functional useof the hand were encouraged. All patients had radiographic and functionalevaluation on follow up at 3 and 6 months. Clinical assessment was based onmodified clinical scoring system of Green and Obrien, radiological assessmentof anatomical results by modified Lidstrom’s criteria and grading of arthritisaccording to Knirk and Jupiter.
5 cases were lost to follow up and thus excluded from the study. All theremaining 17 achieved fracture union. The average follow up was 24 weeks.
The average age was 35 years reflecting the working group susceptible tothis injury and all fractures were a result of falls. All patients recovered fullfinger range of motion. 5 (30%) had excellent outcomes, 4 (24%) had goodoutcomes, 7 (41%) had fair outcomes and 1(5%) had a poor outcomeaccording to the scoring system. There were some complaints of prominentpins and plate, prominent ulnar head.
Our method supports stable internal fixation with plates and wires. Byavoiding problems associated with the extensor tendons and those peculiarto external fixation, it produces good results and can be mastered by mostorthopaedic surgeons.
Strain Rate Effect On The Tensile Properties Of Flexor Tendon
Ng Boon Ho, Chou Siaw Meng, A/Prof Lim Beng Hai
School of Mechanical and Production Engineering, Nanyang
Technological University, Singapore; Dept of Hand &
Reconstructive Microsurg, NUH
Session Presenter : Ng Boon Ho
Tendon, ligament, bone and other biological tissues are known to be viscoelasticmaterial. Their biomechanical properties change with different loading rates.
The change in failure properties of soft tissues at different strain rates is ofparticular interest in analyzing mechanisms of injury. However, the actual Paper physiologic strain rates during soft tissue injury still remain unknown.
Materials and Methods
Seventy-five chicken Flexor Digitorum Profundus (FDP) were tested at 15 differentstrain rates, namely 0.05, 0.1, 0.25, 0.5, 0.75, 1, 2.5, 5, 7.5, 10, 25, 50, 75, 100 and150%/s, and samples were tested at each strain rate in quintuplicate. Mean Free values of Ultimate Tensile Strength, Strain at Maximum Stress, Elastic Modulus and Energy at Maximum Stress were compared at 99% confidence level usingthe Student’s T method.
Results showed that strain rate has little effect on the shape of stress-straincurve.
The lowest mean value of Ultimate Tensile Strength was observed at the loweststrain rate, 0.05 %/s. Generally, Ultimate Tensile Strength increased as strainrate increased. In particular, the mean values obtained at 0.25, 1, 2.5, 10, 50 and100 %/s were significantly higher than the value obtained at 0.05 %/s. Thevalues of Strain at Maximum Stress of all groups did not differ significantly fromthat at 0.05 %/s except at 1 %/s strain rate. In addition, the increase of strainrate resulted in higher Elastic Modulii and the differences were statisticallysignificant against 0.05 %/s except for lower strain rates of 0.1, 0.25, 0.5 and1 %/s. However the linear regression between Elastic Modulus and strain rate(r = 0.642) was not significant for the range of strain rates. In terms of Energyat Maximum Stress, there existed no statistically significant deviation followingthe increase of strain rate.
Discussion and Conclusions
Based on the results obtained, we conclude that strain rate affects the tensileproperties of tendon significantly. Within the range 0.05 to 150 %/s, the stiffnessof tendons increased with the increase of strain rate, with no change in UltimateTensile Strength and Strain at Maximum Stress. However, the change in tendontensile properties was not significant with small change of strain rate.
The Chairman and members of the organising committee of the Review Course in Hand Surgerywould like to express their sincere appreciation to all the Teaching Faculty members and the followings who havegenerously given their support to ensure the success of themeeting Merck Sharp & Dohme (I.A.) Corp.
16 – 18 May 2002
Singapore General Hospital
Alzheimer's & Dementia 2 (2006) 314-321 Factors associated with use of medications with potential to impair cognition or cholinesterase inhibitors among Alzheimer's Edward D. Huey,*, Joy L. Taylor,C, Pauline Luu, John Oehlert, Jared R. Tinklenberg "Cognitive Neuroscience Section, National Institute of Neurological disorders and Stroke, Building 10, Room 5C205, MSC 1440, National