MyMedR

Prediction of height increment using preoperative radiological parameters following selective thoracic fusion with alternate-level pedicle screw construct in Lenke 1 and 2 adolescent idiopathic scoliosis patients

Keong KM, Aziz I, Yin Wei CC

J Orthop Surg (Hong Kong), 2017 01 01;25(1):2309499016684431.

PMID: 29185383 DOI: 10.1177/2309499016684431

PURPOSE: This study aims to derive a formula to predict post-operative height increment in Lenke 1 and Lenke 2 adolescent idiopathic scoliosis (AIS) patients using preoperative radiological parameters.

METHODS: This study involved 70 consecutive Lenke 1 and 2 AIS patients who underwent scoliosis correction with alternate-level pedicle screw instrumentation. Preoperative parameters that were measured included main thoracic (MT) Cobb angle, proximal thoracic (PT) Cobb angle, lumbar Cobb angle as well as thoracic kyphosis. Side-bending flexibility (SBF) and fulcrum-bending flexibility (FBF) were derived from the measurements. Preoperative height and post-operative height increment was measured by an independent observer using a standardized method.

RESULTS: MT Cobb angle and FB Cobb angle were significant predictors ( p < 0.001) of height increment from multiple linear regression analysis ( R = 0.784, R2 = 0.615). PT Cobb angle, lumbar, SB Cobb angle, preoperative height and number of fused segment were not significant predictors for the height increment based on the multivariable analysis. Increase in post-operative height could be calculated by the formula: Increase in height (cm) = (0.09 × preoperative MT Cobb angle) - (0.04 x FB Cobb angle) - 0.5.

CONCLUSION: The proposed formula of increase in height (cm) = (0.09 × preoperative MT Cobb angle) - (0.04 × FB Cobb angle) - 0.5 could predict post-operative height gain to within 5 mm accuracy in 51% of patients, within 10 mm in 70% and within 15 mm in 86% of patients.

Anesthetic considerations in scoliosis patient with dopa-responsive dystonia or Segawa's syndrome

Hasan MS, Leong KW, Chan CY, Kwan MK

J Orthop Surg (Hong Kong), 2017 01;25(1):2309499016684743.

PMID: 28166704 DOI: 10.1177/2309499016684743

Segawa's syndrome or dopa-responsive dystonia is a rare hereditary disorder characterized by progressive dystonia of childhood onset, diurnal fluctuation of symptoms and complete or near complete alleviation of symptoms with administration of low-dose oral levodopa. From our literature search in PubMed, we found only three related publications: two on anesthesia for cesarean section and one on anesthesia for electroconvulsive therapy. We report our experience in providing anesthesia for corrective scoliosis surgery in two biological sisters with Segawa's syndrome. A review of the literature is also included.

Magnetic resonance guided focused ultrasound for treatment of bone tumors

Singh VA, Shah SU, Yasin NF, Abdullah BJJ

J Orthop Surg (Hong Kong), 2017 May-Aug;25(2):2309499017716256.

PMID: 28659052 DOI: 10.1177/2309499017716256

AIMS: Magnetic resonance guided focused ultrasound (MRgFUS) is a new modality in the management of primary and secondary bone tumors. We aimed to investigate the safety, efficacy, and feasibility of using MRgFUS for the treatment of (1) benign bone tumors with the intent of complete tumor ablation, (2) primary malignant bone tumors with the intent to assess its effectiveness in causing tumor necrosis, and (3) metastatic bone disease with the intent of pain relief.

METHOD: Twenty-four patients with benign bone tumors, primary malignant bone tumors, and metastatic bone disease were treated with one session of MRgFUS. Contrast-enhanced (CE) magnetic resonance imaging (MRI) was carried out post-procedure to assess and quantify the area of ablation. Those with malignant primary tumors had the tumors resected 2 weeks after the treatment and the ablated areas were examined histopathologically (HPE). The other patients were followed up for 3 months to assess for the side effects and pain scores.

RESULTS: Significant volume of ablation was noted on CE MRI after the treatment. Benign bone tumors were ablated with minimal adverse effects. Metastatic bone disease was successfully treated with significant decrease in pain scores. Ablated primary malignant tumors showed significant coagulative necrosis on MRI and the HPE showed 100% necrosis. Pain scores significantly decreased 3 months after the procedure. Only two patients had superficial skin blistering and three patients had increase in pain scores immediately after treatment.

CONCLUSION: MRgFUS is effective, safe, and noninvasive procedure that can be an adjunct in the management of primary and metastatic bone tumors.

Effect of intraoperative autologous transfusion techniques on perioperative hemoglobin level in idiopathic scoliosis patients undergoing posterior spinal fusion: A prospective randomized trial

Hasan MS, Choe NC, Chan CYW, Chiu CK, Kwan MK

J Orthop Surg (Hong Kong), 2017 May-Aug;25(2):2309499017718951.

PMID: 28675975 DOI: 10.1177/2309499017718951

BACKGROUND: Massive blood loss during posterior spinal fusion for adolescent idiopathic scoliosis remains a significant risk for patients. There is no consensus on the benefit of acute normovolemic hemodilution (ANH) or intraoperative cell salvage (ICS) in scoliosis surgery.

METHODS: Patients were randomized to one of two groups. Group A received ANH and ICS during operation, while group B received only ICS. Patients' age, sex, height, weight, body blood volume, number of fusion level, Cobb angle, number of screws, duration of surgery, and skin incision length were recorded. Hemoglobin and hematocrit levels were obtained preoperatively and postoperatively (0 h and 24 h).

RESULTS: There were 22 patients in each group. There was no significant difference in total blood loss. The perioperative decrease in hemoglobin levels between preoperation and postoperation 24 h (group A 2.79 ± 1.15 and group B 2.76 ± 1.00) showed no significant difference ( p = 0.93). Group A observed a larger decrease in hemoglobin levels at postoperative 0 h relative to preoperative level (2.57 ± 0.82 g/dl), followed by a smaller decrease within the next 24 h (0.22 ± 1.33 g/dl). Group B showed a continued drop in hemoglobin levels of similar magnitude at postoperation 0 h (1.60 ± 0.67 g/dl) and within the next 24 h (1.16 ± 0.78 g/dl). One patient from group B received 1 unit of allogenic blood transfusion ( p = 0.33).

CONCLUSIONS: The addition of ANH to ICS in posterior spinal fusion surgery for AIS resulted in a similar decrease in hemoglobin levels between preoperative values and at 24 h postoperatively.

The accuracy and safety of fluoroscopic-guided percutaneous pedicle screws in the thoracic and lumbosacral spine in the Asian population: A CT scan analysis of 1002 screws

Chiu CK, Chan CYW, Kwan MK

J Orthop Surg (Hong Kong), 2017 May-Aug;25(2):2309499017713938.

PMID: 28705124 DOI: 10.1177/2309499017713938

PURPOSE: This study investigates the safety and accuracy of percutaneous pedicle screws placed using fluoroscopic guidance in the thoracolumbosacral spine among Asian patients.

METHODS: Computerized tomography scans of 128 patients who had surgery using fluoroscopic-guided percutaneous pedicle screws were selected. Medial, lateral, superior, and inferior screw perforations were classified into grade 0 (no violation), grade 1 (<2 mm perforation), grade 2 (2-4 mm perforation), and grade 3(>4 mm perforation). Anterior perforations were classified into grade 0 (no violation), grade 1 (<4 mm perforation), grade 2 (4-6 mm perforation), and grade 3(>6 mm perforation). Grade 2 and grade 3 perforation were considered as "critical" perforation.

RESULTS: In total, 1002 percutaneous pedicle screws from 128 patients were analyzed. The mean age was 52.7 ± 16.6. There were 70 male patients and 58 female patients. The total perforation rate was 11.3% (113) with 8.4% (84) grade 1, 2.6% (26) grade 2, and 0.3% (3) grade 3 perforations. The overall "critical" perforation rate was 2.9% (29 screws) and no complications were noted. The highest perforation rates were at T4 (21.6%), T2 (19.4%), and T6 (19.2%).

CONCLUSION: The total perforation rate of 11.3% with the total "critical" perforation rate of 2.9% (2.6% grade 2 and 0.3% grade 3 perforations). The highest perforation rates were found over the upper to mid-thoracic region. Fluoroscopic-guided percutaneous pedicle screws insertion among Asians has the safety and accuracy comparable to the current reported percutaneous pedicle screws and open pedicle screws techniques.

Perceived comfort during minor hand surgeries with wide awake local anaesthesia no tourniquet (WALANT) versus local anaesthesia (LA)/tourniquet

Gunasagaran J, Sean ES, Shivdas S, Amir S, Ahmad TS

J Orthop Surg (Hong Kong), 2017 Sep-Dec;25(3):2309499017739499.

PMID: 29141522 DOI: 10.1177/2309499017739499

PURPOSE: Minor hand surgeries can be done under field sterility in procedure rooms. Surgeons are still sceptical about the usage of wide awake local anaesthesia no tourniquet (WALANT) technique. They perceive that patients can tolerate tourniquet for a brief period while they perform minor surgeries under local anaesthesia (LA). We compared the perceived comfort experienced by patients during minor hand surgeries with WALANT and LA/tourniquet. We investigated the difference in preoperative preparation time, operating time and blood loss between the two groups.

METHODS: Between July and October 2016, a total of 72 patients were diagnosed with carpal tunnel syndrome, trigger finger or ganglion, at the University Malaya Medical Centre. Forty patients consented to participate in this study and were randomized into WALANT and LA/tourniquet groups. Anaesthesia was administered accordingly and tourniquet was applied. The time taken for preoperative preparation and surgery was recorded. Each surgeon estimated the blood loss. The perceived comfort level of each patient was quantified using a visual analogue score (VAS). Data were analysed using SPSS.

RESULTS: The mean VAS for the WALANT group was 2.33 ± 1.94, whereas it was 4.72 ± 3.05 for the LA/tourniquet group, and the difference was statistically significant ( p < 0.05). The mean time for preoperative preparation in WALANT group was 19.17 ± 12.61 min and LA/tourniquet group was 7.05 ± 3.44 min. The difference between these groups was statistically significant ( p < 0.01). There was no significant difference in operating time and blood loss.

CONCLUSION: WALANT technique was associated with better patient comfort. Tourniquet was the main reason for discomfort during surgeries. WALANT is an alternative in minor hand surgeries for a bloodless surgical field without the discomfort of tourniquet application.

Remarkable bone formation following gefitinib for extensive lytic bone metastasis: a report of two cases

Bashir ES, Kwan AK, Chan CY, Mun Keong K

J Orthop Surg (Hong Kong), 2016 12;24(3):421-423.

PMID: 28031519

Gefitinib inhibits the epidermal growth factor receptor tyrosine kinase and improves survival in patients with non-small-cell lung cancer. We report 2 patients with extensive lytic bony metastasis in the spine and pelvis secondary to advanced pulmonary adenocarcinoma who were treated with gefitinib and had remarkable bone formation in the lytic bone lesions in the spine and pelvis. Surgery for stabilisation was avoided.

Posterior spinal instrumented fusion for idiopathic scoliosis in patients with multisystemic neurodegenerative disorder: a report of two cases

Loh KW, Chan CY, Chiu CK, Bin Hasan MS, Kwan MK

J Orthop Surg (Hong Kong), 2016 08;24(2):273-7.

PMID: 27574278

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke (MELAS) syndrome is a progressive multisystemic neurodegenerative disorder. MELAS syndrome impairs oxidative phosphorylation and predisposes patients to lactic acidosis, particularly under metabolic stress. We report 2 siblings with MELAS-associated idiopathic scoliosis who underwent posterior spinal instrumented fusion with measures taken to minimise anaesthetic and surgical stress, blood loss, and operating time.

Fulltext Editorial: Open access model for the Journal of Orthopaedic Surgery

Choon D

J Orthop Surg (Hong Kong), 2016 08;24(2):143.

PMID: 27574248 DOI: 10.1177/1602400201

Letter to the Editor: Minimally invasive plate osteosynthesis for proximal humeral fractures

Sinha N, Rao BS, Trivedy PD, Rao AS

J Orthop Surg (Hong Kong), 2016 04;24(1):139.

PMID: 27122535

Letter to the Editor: Factors associated with one-year outcome after distal radial fracture treatment

Sinha N, Rao BS, Bhardwaj A, Singh S

J Orthop Surg (Hong Kong), 2015 Aug;23(2):272.

PMID: 26321570

Extraskeletal myxoid chondrosarcoma of the thigh in a child: a case report

Ibrahim ZA, Chan WH, Wong SL, Ong EJ, Narihan MZ

J Orthop Surg (Hong Kong), 2014 Dec;22(3):423-6.

PMID: 25550031

Extraskeletal myxoid chondrosarcoma (EMC) is aggressive in children. The condition in children differs to that in adults and to skeletal myxoid chondrosarcoma. We report on a 9-year-old girl with EMC in her left thigh. She underwent above-knee amputation. Five months later, a small mass was noted at the right lower lobe of the lung. The patient underwent one course of ifosfamide, carboplatin, and etoposide chemotherapy, followed by resection of the mass and 8 more courses of chemotherapy. At the 2-year follow-up, she was in remission radiologically.

Reconstruction for chronic grade-II posterior cruciate ligament deficiency in Malaysian military personnel

Ahmad S, Mahidon R, Shukur MH, Hamdan A, Kasmin M

J Orthop Surg (Hong Kong), 2014 Dec;22(3):325-8.

PMID: 25550011

To evaluate the outcome of reconstruction for chronic grade-II posterior cruciate ligament (PCL) deficiency in Malaysian military personnel.

Insertional torque and pullout strength of pedicle screws with or without repositioning: a porcine study

Tan CE, Fok MW, Luk KD, Cheung KM

J Orthop Surg (Hong Kong), 2014 Aug;22(2):224-7.

PMID: 25163961

PURPOSE. To evaluate the insertion torque and pullout strength of pedicle screws with or without repositioning. METHODS. 20 fresh porcine lumbar vertebrae of similar size were used. The entry point was at the site just lateral and distal to the superior facet joint of the vertebra, and to a depth of 35 mm. A 6.2-mm-diameter, 35-mm-long pedicle screw was inserted parallel to the superior end plate on one side as control. On the other side, an identical screw was first inserted 10º caudal to the superior end plate, and then repositioned parallel to the superior end plate. The insertional torque and pullout strength were measured. RESULTS. Three of the specimens were excluded owing to pedicle fractures during the pullout test. Repositioned pedicle screws were significantly weaker than controls in terms of the maximum insertional torque (3.20 ± 0.28 vs. 2.04 ± 0.28 Nm, 36% difference, p<0.01) and pullout strength (1664 ± 378 vs.1391 ± 295 N, p<0.01). CONCLUSION. Repositioning pedicle screws should be avoided, especially when the pedicle wall is breached. If repositioning is deemed necessary, augmentation with polymethyl methacrylate or a screw with a larger diameter should be considered.

A 45-degree radiographic method for measuring the neck shaft angle and anteversion of the femur: a pilot study

Teo PC, Kassim AY, Thevarajan K

J Orthop Surg (Hong Kong), 2013 Dec;21(3):340-6.

PMID: 24366797

To propose a novel method to measure the neck shaft angle and anteversion of the femur using anteroposterior and 45-degree oblique radiographs.

Fulltext Editorial: Evidence-based medicine

Sivananthan DK

J Orthop Surg (Hong Kong), 2013 Aug;21(2):139.

PMID: 24014768

Commentary: Position of the patella in adults in central India: evaluation of the Insall-Salvati ratio

Choon DS

J Orthop Surg (Hong Kong), 2013 Apr;21(1):3.

PMID: 23629977

Rates of pin site infection during distraction osteogenesis based on monthly observations: a pilot study

Saw A, Chua YP, Hossain G, Sengupta S

J Orthop Surg (Hong Kong), 2012 Aug;20(2):181-4.

PMID: 22933675

To assess the monthly rates of infection of individual pin sites in 7 patients during distraction osteogenesis.

Breakage of an intramedullary rod after bone union in congenital pseudoarthrosis of the tibia: a report of two cases

Sulaiman AR, Simbak N, Wan Ismail WF, Wan Z, Halim AS

J Orthop Surg (Hong Kong), 2011 Aug;19(2):250-3.

PMID: 21857057

We report 2 patients with congenital pseudoarthrosis of the tibia who underwent intramedullary Rush rod transfixation through the ankle joint following refracture and nonunion of vascularised fibular grafting 6 and 8 months earlier. After 9 and 5 years, both Rush rods were broken at the level of the ankle joints, while the reconstructed area was solidly united. The growth of the distal tibia increased the distance of the tips of the broken rod and hence the ankle joint motion. The broken tips may damage the articular cartilage and result in valgus deformity of the ankle and limb length discrepancy.

Tribute to a pioneer and leader in orthopaedic surgery

J Orthop Surg (Hong Kong), 2011 Apr;19(1):1-2.

PMID: 21519066

Displaying publications 61 - 80 of 113 in total