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Fulltext Automatic top loader washing machine related injury. A report of four cases with serious injury

Kwan MK, Saw A, Sara Ahmad T

Med J Malaysia, 2005 Mar;60(1):112-4.
PMID: 16250295 MyJurnal

We are reporting four cases of serious washing machine related injury that presented within a period of 5 months. All patients were young children with the mean age of 9 year-old and three had their dominant hand injured. The washing machines involved were the automatic top loader type and all injuries occurred during the spinning phase. Serious automatic washing machine injury is not uncommon in Malaysia. We feel that there is a need to improve the safety features especially during the spinning phase. The operating instructions and safety precautions on the washing machine should be displayed in different languages that can be understood well. Parents should also aware of the potential risks of this seemingly benign household appliance.
Fulltext Treatment for flexion contracture of the knee during Ilizarov reconstruction of tibia with passive knee extension splint

Kwan MK, Penafort R, Saw A

Med J Malaysia, 2004 Dec;59 Suppl F:39-41.
PMID: 15941159

Joint stiffness is one of the complications of limb procedure. It developes as a result of failure of knee flexors to lengthen in tandem with the bone, especially when there is inadequate physical therapy to provide active and passive mobilization of the affected joint. We are reporting four patients who developed fixed flexion contracture of their knees during bone lengthening procedure for the tibia with Ilizarov external fixator. Three of them were treated for congenital pseudoarthrosis and one was for fibular hemimelia. None of them were able to visit the physiotherapist even on a weekly basis. A splint was constructed from components of Ilizarov external fixator and applied on to the existing frame to passively extend the affected knee. Patients and their family members were taught to perform this exercise regularly and eventually near complete correction were achieved. With this result, we would like to recommend the use of this "Passive Knee Extension Splint" to avoid knee flexion Contracture during limb lengthening procedures with Ilizarov external fixators.
Is there an optimal upper instrumented vertebra (UIV) tilt angle to prevent post-operative shoulder imbalance and neck tilt in Lenke 1 and 2 adolescent idiopathic scoliosis (AIS) patients?

Kwan MK, Chan CY

Eur Spine J, 2016 10;25(10):3065-3074.
PMID: 27021616

PURPOSE: To investigate whether an optimal upper instrumented vertebra (UIV) tilt angle would prevent 'lateral' shoulder imbalance or neck tilt (with 'medial' shoulder imbalance) post-operatively.
METHODS: The mean follow-up for 60 AIS (Lenke 1 and Lenke 2) patients was 49.3 ± 8.4 months. Optimal UIV tilt angle was calculated from the cervical supine side bending radiographs. Lateral shoulder imbalance was graded using the clinical shoulder grading. The clinical neck tilt grading was as follows: Grade 0: no neck tilt, Grade 1: actively correctable neck tilt, Grade 2: neck tilt that cannot be corrected by active contraction and Grade 3: severe neck tilt with trapezial asymmetry >1 cm. T1 tilt, clavicle angle and cervical axis were measured. UIVDiff (difference between post-operative UIV tilt and pre-operative Optimal UIV tilt) and the reserve motion of the UIV were correlated with the outcome measures. Patients were assessed at 6 weeks and at final follow-up with a minimum follow-up duration of 24 months.
RESULTS: Among patients with grade 0 neck tilt, 88.2 % of patients had the UIV tilt angle within the reserve motion range. This percentage dropped to 75.0 % in patients with grade 1 neck tilt whereas in patients with grade 2 and grade 3 neck tilt, the percentage dropped further to 22.2 and 20.0 % (p = 0.000). The occurrence of grade 2 and 3 neck tilt when UIVDiff was <5°, 5-10° and >10° was 9.5, 50.0 and 100.0 %, respectively (p = 0.005). UIVDiff and T1 tilt had a positive and strong correlation (r2 = 0.618). However, UIVDiff had poor correlation with clavicle angle and the lateral shoulder imbalance.
CONCLUSION: An optimal UIV tilt might prevent neck tilt with 'medial' shoulder imbalance due to trapezial prominence and but not 'lateral' shoulder imbalance.
Zonal differences in risk and pattern of pedicle screw perforations in adolescent idiopathic scoliosis (AIS): a computerized tomography (CT) review of 1986 screws

Chan CYW, Kwan MK

Eur Spine J, 2018 02;27(2):340-349.
PMID: 29058137 DOI: 10.1007/s00586-017-5350-x

PURPOSE: To evaluate the zonal differences in risk and pattern of pedicle screw perforations in adolescent idiopathic scoliosis (AIS) patients.
METHODS: The scoliosis curves were divided into eight zones. CT scans were used to assess perforations: Grade 0, Grade 1( 4 mm). Anterior perforations were classified into Grade 0, Grade 1( 6 mm). Grade 2 and 3 (except lateral grade 2 and 3 perforation over thoracic vertebrae) were considered as 'critical perforations'.
RESULTS: 1986 screws in 137 patients were analyzed. The overall perforation rate was 8.4% after exclusion of the lateral perforation. The highest medial perforation rate was at the transitional proximal thoracic (PT)/main thoracic (MT) zone (6.9%), followed by concave lumbar (6.7%) and convex main thoracic (MT) zone (6.1%). The overall critical medial perforation rate was 0.9%. 33.3% occurred at convex MT and 22.2% occurred at transitional PT/MT zone. There were 39 anterior perforations (overall perforation rate of 2.0%). 43.6% occurred at transitional PT/MT zone, whereas 23.1% occurred at concave PT zone. The overall critical anterior perforation rate was 0.6%. 5/12 (41.7%) critical perforations occurred at concave PT zone, whereas four perforations occurred at the transitional PT/MT zone. There were only two symptomatic left medial grade 2 perforations (0.1%) resulting radiculopathy, occurring at the transitional main thoracic (MT)/Lumbar (L) zone.
CONCLUSION: Overall pedicle perforation rate was 8.4%. Highest rate of critical medial perforation was at the convex MT zone and the transitional PT/MT zone, whereas highest rate of critical anterior perforation was at the concave PT zone and the transitional PT/MT zone. The rate of symptomatic perforations was 0.1%.
Fulltext Necrotising fasciitis: a life-threatening complication of acupuncture in a patient with diabetes mellitus

Saw A, Kwan MK, Sengupta S

Singapore Med J, 2004 Apr;45(4):180-2.
PMID: 15094988

Acupuncture is used for some conditions as an alternative to medication or surgical intervention. Several complications had been reported, and they are generally due to physical injury by the needle or transmission of diseases. We report a case of life-threatening necrotising fasciitis that developed after acupuncture treatment for osteoarthritis of the knee in a 55-year-old diabetic woman. She presented with multiple discharging sinuses over the right knee. As the patient did not respond to intravenous antibiotics, extensive debridement was performed. She made a good recovery. Since many old diabetic patients with degenerative joint diseases may consider this mode of treatment, guidelines on cleanliness and sterility of this procedure should be developed and practiced.
Diluted povidone-iodine versus saline for dressing metal-skin interfaces in external fixation

Chan CK, Saw A, Kwan MK, Karina R

J Orthop Surg (Hong Kong), 2009 Apr;17(1):19-22.
PMID: 19398787

To compare infection rates associated with 2 dressing solutions for metal-skin interfaces.
Fulltext Quantitative and qualitative evaluation of sural nerve graft donor site

Ng SS, Kwan MK, Ahmad TS

Med J Malaysia, 2006 Dec;61 Suppl B:13-7.
PMID: 17600987

This study is designed to evaluate twenty patients after sural nerve harvest using the single longitudinal incision method. The area of sensory loss to pin prick was assessed by the authors at different intervals. Donor site factors, scar cosmesis, functional status and complications were assessed using a questionnaire. The mean area of anaesthesia at one month was 65 cm2 and it had reduced by 77% to 15 cm2 at one and a half years. The mean area of reduced sensation was 49 cm2 at one month and it increased by 18% to 58 cm2 over the same period. Therefore, the total area of sensory deficit was reduced by 36% from 114 cm2 at one month to 73 cm2 at one and a half years. Subjective patient evaluation indicated moderate level of pain during immediate post surgical period, which reduced significantly at one month. A low level of neuroma symptoms was recorded throughout the study period. At a mean follow-up period of two years, there was no area of anaesthesia in 50% of the patients. Mean area of anaesthesia for all patients was 12 cm2 and mean area of reduced sensation was 55 cm2. Subjective patient evaluation indicated a low level of pain, neuroma symptoms and numbness over the sural nerve sensory distribution. Twenty five percent of the patients were not satisfied with the scar appearance. Function and daily activities were not affected significantly. No surgical complications were observed.
Fulltext Operative treatment of trochanteric fractures with dynamic hip screw--is perioperative blood transfusion needed?

Chua YP, Kwan MK, Saw A

Med J Malaysia, 2005 Jul;60 Suppl C:78-82.
PMID: 16381289

The need for perioperative blood transfusion in elderly patients with trochanteric fracture scheduled for elective dynamic hip screw fixation has recently been questioned following reports on the association between allogeneic blood transfusion and post-operative infections. This retrospective study was undertaken to assess the amount of per operative blood loss and transfusion requirement in relation to pre-operative haemoglobin level in 198 patients with trochanteric fractures. The average per operative blood loss was 409 ml and it correlated well with the duration of the operation. More than half of the patients (52.5%) required blood transfusion and nearly three-quarters were anaemic prior to the surgery. Proactive pre-operative measures to optimize the patient's haemoglobin level and intra-operative minimization of blood loss are essential steps to obviate the need for perioperative allogeneic blood transfusion.
Fulltext Reconstruction of the heel defect with in-step island flap. A report of four cases

Kwan MK, Marican AM, Ahmad TS

Med J Malaysia, 2005 Jul;60 Suppl C:104-7.
PMID: 16381293

Soft tissue loss of the heel is difficult to treat as it may cause significant morbidity particularly recurrent ulceration and subsequent chronic osteomyelitis. Reconstruction of such defect with local flap can provide good result. We report our experience in treating four patients with heel defect using the in-step island flap. The flap, which is based on the medial plantar neurovascular pedicle, provides a sensate durable tissue required for weight-bearing and normal gait.
Fulltext Coronal plane and apical vertebral rotation correction of adolescent idiopathic scoliosis with multisegmented hook-rod system--a retrospective review

Kwan MK, Chooi WK, Lim HH

Med J Malaysia, 2004 Dec;59 Suppl F:14-8.
PMID: 15941155

Between April 1998 and December 1999, thirty patients with Idiopathic Scoliosis were operated with Multisegmented Hook-Rod System. These patients were operated at the mean age of 16 years and were followed up for a mean of 22.3 months (range 13-34 months). Seven patients had anterior release to increase the curve flexibility followed by second stage posterior instrumentation on the same day. The average operating time for a posterior instrumentation alone and anterior release combined with posterior instrumentation were 270 minutes and 522 minutes respectively. The average blood loss was 2.2 litres for posterior instrumentation alone and 3.3 litres for single day anterior release and posterior surgery. The mean preoperative Cobb's angle was 70 degrees. The mean immediate postoperative and final follow up Cobb's angles were 38 and 42 degrees, which represented an average coronal plane correction of 46.7% and 40.0% respectively. The mean preoperative apical vertebral rotation was 25 degrees, which improved to 15 degrees after the operation. At final follow up, the mean apical vertebra rotation was 20 degrees, which represented a mean apical vertebral rotation correction of 20%. Complications of the procedure included one transient neurological deficit, one infection, one graft site infection and one case of screw cut out. We were able to obtain satisfactory correction of idiopathic scoliosis with the Multisegmented Hook-Rod System.
Fulltext Improved Accuracy and Safety of Intracorporeal Transpedicular Bone Grafting - using Contrast Impregnated Bone: A Case Report

Chiu CK, Chan C, Kwan MK

Malays Orthop J, 2014 Nov;8(3):27-9.
PMID: 26401232 MyJurnal DOI: 10.5704/MOJ.1411.006

A method of transpedicular bone grafting using contrast impregnated bone to improve the visualization of bone graft on the image intensifier is reported. A - 36-year old man who had sustained traumatic burst fracture of T12 vertebra, with Load-Sharing Classification (LSC) score of 8, was treated with posterior short segment fusion from T11 to L1 with transpedicular bone graft of T12 vertebra. We were able to correct the kyphotic end plate angle (EPA) from 19º to 1.4º. Anterior bone graft augmentation was achieved with contrast enhaced transpedicular bone grafts. At six months follow up, CT scan showed good bony integration of the anterior column with EPA of 4.5º and two years later, radiographs showed EPA of 7.6 º.
Fulltext Melioidotic osteomyelitis treated with antibiotic-calcium hydroxyapatite composite: case report with four-year follow-up

Ng WM, Kwan MK, Merican AM

Singapore Med J, 2006 Jan;47(1):71-4.
PMID: 16397726

Melioidosis is caused by an infection by Burkholderia pseudomallei. Osteomyelitis is a recognised manifestation of melioidosis but Burkholderia pseudomallei is a relatively rare aetiological agent in musculoskeletal infections. We report a 32-year-old diabetic man with septicaemia due to melioidotic infection of the spleen, liver and distal femur. The osteomyelitis relapsed despite being treated with the standard radical debridement and insertion of gentamycinimpregnated polymethylmetacrylate (PMMA) beads, followed by an optimal antibiotic therapy. The PMMA-gentamycin beads were then removed. The bone defect was debrided and packed with calcium hydroxyapatite blocks filled with ceftazidime powder. The osteomyelitis was successfully treated and the patient remained free of infection four years postoperatively. Computed tomography demonstrated successful incorporation of the calcium hydroxyapatite into host bone.
Fulltext Femoral Shaft Cortical Pathology associated with longterm Alendronate Therapy: A New Classification

Kwan M, Chan C, Ng W, Merican A, Chung W, Chan S

Malays Orthop J, 2013 Jul;7(2):12-7.
PMID: 25722819 MyJurnal DOI: 10.5704/MOJ.1307.008

There are reported cases of cortical reaction over the tension side of the normal femoral shafts in patients on long term treatment with alendronate, leading to subsequent femoral shaft fractures. We performed a retrospective review of patients with low-energy femoral shaft fracture on alendronate, admitted to our institution during the period 2004 to May 2009. The presence of radiological changes of cortical hypertrophy with or without Looser's zone over the tension side of the femoral bone (normal limb) was determined and correlated with clinical symptoms. Thirteen patients were identified. Average duration of alendronate use was 6.5 ± 3.3 years (ranges, two to 10 years). These radiological changes were noted in four patients. Average duration of alendronate usage in these four patients was 6.5 ± 2.4 years (ranges, 5 to10 years). Prodromal thigh pain was present in a patient, who had cortical hypertrophy with the presence of a Looser's zone traversing the cortex on the femoral shaft. One patient had Looser's zone limited at the lateral hypertrophied cortex without prodromal pain. The interobserver kappa coefficient was 0.96. A femoral radiograph should be performed in all patients who are on long-term alendronate therapy who present with thigh pain. We propose a new grading system based on our observation of the radiological features in these four cases. This new grading of the radiological spectrum of femoral shaft cortical pathology has the potential to stratify the risk of low energy femoral fracture for patients treated with long-term alendronate therapy.
U-shaped sacral fracture: an easily missed fracture with high morbidity. A report of two cases

Hussin P, Chan CY, Saw LB, Kwan MK

Emerg Med J, 2009 Sep;26(9):677-8.
PMID: 19700594 DOI: 10.1136/emj.2008.064972

U-shaped sacral fracture is a very rare injury. This injury is easily missed and the diagnosis is often delayed as it is difficult to detect on the anteroposterior view of the pelvic radiograph. It is highly unstable and neurological injury is common. Two cases of U-shaped sacral fractures are reported here in which the diagnosis was delayed resulting in the late development of cauda equina syndrome. In these two cases, full recoveries were achieved following surgical decompression. A high index of suspicion with proper clinical and radiographic assessments will decrease the incidence of missed diagnosis and prevent the occurrence of delayed neurological deficits.
Fulltext Total knee replacement subsequent to severe necrotising fasciitis of the lower limb

Ling HT, Kwan MK, Saw A, Choon DS

Med J Malaysia, 2006 Aug;61(3):380-2.
PMID: 17240598 MyJurnal

The incidence of wound related complication following total knee arthroplasty is as high as 10%-20%. To perform total knee arthroplasty in a knee with extensive scarring around the knee can be a challenging task. We report a case of 55-year-old diabetic woman, who had total knee arthroplasty, performed two years after she had recovered from necrotizing fasciitis around the right knee. Understanding the vascular anatomy around the knee is of paramount importance in the planning of skin incision to ensure fewer wound related complications.
Fulltext Resection arthrodesis for primary bone tumour about the knee

Kwan MK, Ng ES, Penafort R, Saw A, Sengupta S

Med J Malaysia, 2005 Jul;60 Suppl C:66-71.
PMID: 16381287 MyJurnal

Bone defect following en bloc resection of primary bone tumor around the knee can be reconstructed by allograft or prothesis or combination of both. Resection-arthrodesis is an alternative option for young vigorous patients facing circumstances of financial constrain or limited supply of allograft. This study was undertaken to determine the outcome and complications associated with resection-arthrodesis of 22 primary bone tumors (13 giant cell tumors and 9 osteosarcomas) around the knee treated between 1990 and 2003 at the University Malaya Medical Center. The mean follow-up was 6 years (range 1-13 years). hree patients with osteosarcoma died of lung metastasis, 3 required above knee amputation and 2 defaulted follow-up. Local complications of the procedure include infection in 8 cases (36.4%), non-union 7 (31.8%) and mal-union. Of 14 patients who returned for final evaluation, 79.8% had satisfactory outcomes according to the Musculoskeletal Tumor Society grading system. In conclusion, resection-arthrodesis of the knee is a viable treatment option for selected patients with primary bone tumor around the knee, and good functional outcome can be expected in the presence of short-term local complications.
Fulltext Shoulder arthrodesis in brachial plexus injuries--a review of six cases

Wong ELW, Kwan MK, Loh WYC, Ahmad TS

Med J Malaysia, 2005 Jul;60 Suppl C:72-7.
PMID: 16381288

Shoulder arthrodesis is a secondary reconstructive option for patients with brachial plexus injuries requiring a stable shoulder. This study was undertaken to evaluate the clinical and radiological outcomes of shoulder fusion in six patients with flail upper limbs following complete brachial plexus injuries. The shoulder was fused in 30 degrees abduction, 30 degrees internal rotation and 30 degrees flexion via a direct lateral approach by using a 4.5 mm reconstruction plate without bone grafting. The average follow-up was 10.3 months. Radiological union was obtained in all patients. Five patients (83%) had relief of pain after the shoulder fusion. Improvement of function was observed in all patients with a mean improvement of 56.6 degrees (range 30 degrees-75 degrees) and 47.5 degrees (range 30 degrees-60 degrees) active flexion and abduction respectively. One patient developed humeral fracture distal to the plate and the fracture eventually healed with a splint. Successful stable fusion of the shoulder in patients with brachial plexus injuries requires rigid fixation with a single 4.5 mm reconstruction plate, protection of bone healing with a triangular abduction brace for 12 weeks and functional trapezius, levator scapulae, serratus anterior and rhomboid muscles for optimizing the functional result.
Fulltext Apollo total knee replacements in University Malaya Medical Centre: a short-term outcome

Abbas AA, Merican AM, Kwan MK, Mohamad JA

Med J Malaysia, 2006 Feb;61 Suppl A:83-7.
PMID: 17042237

Total knee arthroplasty is the most preferred option for treatment of severe osteoarthritis of the knee. We report the short-term outcome of 48 total knee replacements in 31 patients utilizing the Apollo Total Knee System after an average follow-up of 48 months (range 15 to 70 months). Records of all patients who underwent TKA using Apollo Total Knee System were retrospectively reviewed. Functional outcome was evaluated using visual analogue scale for pain rating and the Oxford 12-item questionnaire. Postoperative radiographs of the replaced knees were assessed by using the Knee Society Total Knee Arthroplasty Roentgenographic Evaluation and Scoring System. Degenerative osteoarthritis was the commonest indication for TKA. The average patient's age was 63.7 years (range, 30-77 years). The mean visual analogue scale for pre- and post-operative pain was eight and zero respectively. The mean Oxford 12-item questionnaire score pre- and post-operatively was 44.8 and 16.5 respectively. Patient satisfaction was notable in 98% of the cases with an average improvement in arc of flexion of 111 degrees. There were four failures; deep infection (one) and aseptic loosening (three) giving rise to a 94% implant survivor. The short-term results of this series is comparable with or better than a number of outcome studies of the Apollo Knee System or other implants of similar design.
Comparison between percutaneous fluoroscopic-guided and conventional open pedicle screw placement techniques for the thoracic spine: a safety evaluation in human cadavers

Kwan MK, Chiu CK, Lee CK, Chan CY

Bone Joint J, 2015 Nov;97-B(11):1555-61.
PMID: 26530660 DOI: 10.1302/0301-620X.97B11.35789

Percutaneous placement of pedicle screws is a well-established technique, however, no studies have compared percutaneous and open placement of screws in the thoracic spine. The aim of this cadaveric study was to compare the accuracy and safety of these techniques at the thoracic spinal level. A total of 288 screws were inserted in 16 (eight cadavers, 144 screws in percutaneous and eight cadavers, 144 screws in open). Pedicle perforations and fractures were documented subsequent to wide laminectomy followed by skeletalisation of the vertebrae. The perforations were classified as grade 0: no perforation, grade 1: < 2 mm perforation, grade 2: 2 mm to 4 mm perforation and grade 3: > 4 mm perforation. In the percutaneous group, the perforation rate was 11.1% with 15 (10.4%) grade 1 and one (0.7%) grade 2 perforations. In the open group, the perforation rate was 8.3% (12 screws) and all were grade 1. This difference was not significant (p = 0.45). There were 19 (13.2%) pedicle fractures in the percutaneous group and 21 (14.6%) in the open group (p = 0.73). In summary, the safety of percutaneous fluoroscopy-guided pedicle screw placement in the thoracic spine between T4 and T12 is similar to that of the conventional open technique.
The accuracy and safety of fluoroscopically guided percutaneous pedicle screws in the lumbosacral junction and the lumbar spine: a review of 880 screws

Chiu CK, Kwan MK, Chan CY, Schaefer C, Hansen-Algenstaedt N

Bone Joint J, 2015 Aug;97-B(8):1111-7.
PMID: 26224830 DOI: 10.1302/0301-620X.97B8.35330

We undertook a retrospective study investigating the accuracy and safety of percutaneous pedicle screws placed under fluoroscopic guidance in the lumbosacral junction and lumbar spine. The CT scans of patients were chosen from two centres: European patients from University Medical Center Hamburg-Eppendorf, Germany, and Asian patients from the University of Malaya, Malaysia. Screw perforations were classified into grades 0, 1, 2 and 3. A total of 880 percutaneous pedicle screws from 203 patients were analysed: 614 screws from 144 European patients and 266 screws from 59 Asian patients. The mean age of the patients was 58.8 years (16 to 91) and there were 103 men and 100 women. The total rate of perforation was 9.9% (87 screws) with 7.4% grade 1, 2.0% grade 2 and 0.5% grade 3 perforations. The rate of perforation in Europeans was 10.4% and in Asians was 8.6%, with no significant difference between the two (p = 0.42). The rate of perforation was the highest in S1 (19.4%) followed by L5 (14.9%). The accuracy and safety of percutaneous pedicle screw placement are comparable to those cited in the literature for the open method of pedicle screw placement. Greater caution must be taken during the insertion of L5 and S1 percutaneous pedicle screws owing to their more angulated pedicles, the anatomical variations in their vertebral bodies and the morphology of the spinal canal at this location.

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