A novel practical method to predict anterior cruciate ligament hamstring graft size using preoperative MRI.

BACKGROUND: Predicting hamstring graft size preoperatively for anterior cruciate ligament (ACL) reconstruction is important for preempting an insufficient diameter in graft size intraoperatively, possibly leading to graft failure. While there are multiple published methods using magnetic resonance imaging (MRI) picture archiving and communication systems (PACS), most are not feasible and practical. Our study aims to (1) practically predict the ACL hamstring graft size in a numerically continuous manner using the preoperative MRI from any native MRI PACS system, (2) determine the degree of correlation between the predicted and actual graft size, and (3) determine the performance of our prediction method if we define an adequate actual graft size as ≥ 8 mm. METHODS: A retrospective review of 112 patients who underwent primary ACL reconstruction with quadrupled hamstring semitendinosus-gracilis grafts at a tertiary institution was conducted between January 2018 and December 2018. Graft diameter can be predicted in a numerically continuous manner as √[2*(AB + CD)], where A and B are the semitendinosus cross-sectional length and breath, respectively, and C and D are the gracilis cross-sectional length and breath, respectively. RESULTS: A moderately positive correlation exists between the predicted and actual graft diameter (r = 0.661 and p < .001). Our method yields a high specificity of 92.6% and a moderate sensitivity of 67.2% if we define an adequate actual graft size as ≥ 8 mm. An area under receiver-operating characteristic curve shows good discrimination (AUC = 0.856). CONCLUSIONS: We present a practical method to predict the ACL hamstring graft size with high specificity using preoperative MRI measurements.

Current concepts of bone grafting in trauma surgery.

Bone graft in trauma surgery is commonly used in managing bone defects, non-union, fracture related infections, arthrodesis or to provide structural support in fractures. A variety of bone grafts are made available to the treating physician, which includes autograft, allograft and bone graft substitutes. The future of bone grafting in trauma surgery is exciting with the incorporation of technological advancement such as gene therapy, 3D-printing and tissue engineering. Regardless, there are still limitations to what we understand regarding current bone grafting techniques with conflicting literature on their clinical utility and indication. The aim of this review article therefore is to take a step back and critically evaluate the current concepts of bone grafting in trauma surgery, with special emphasis made on reviewing the types of bone graft, biology of bone graft incorporation and indication for its use in various clinical scenarios.

Telemedicine use in orthopaedics: Experience during the COVID-19 pandemic.

INTRODUCTION: With a recent resurgence of the 2019 coronavirus disease (COVID-19) cases globally, an increasing number of healthcare systems are adopting telemedicine as an alternative method of healthcare delivery in a bid to decrease disease transmission. Continued care of orthopaedic patients in the outpatient setting during the coronavirus disease of 2019 era can prove challenging without a systematic workflow, adequate logistics, and careful patient selection for teleconsultation. The aim of this paper is to describe our single-centre experience with the application of telemedicine in our orthopaedic practice, and its effectiveness in maintaining outpatient follow-up of orthopaedic patients. METHODOLOGY: We describe our centre's telemedicine model of care for orthopaedic patients on the outpatient follow-up - which includes workforce assembly, population health and target patients, logistics and communications, and overall workflow - with roles and responsibilities of involved people portrayed in detail. RESULTS: Feedback from both patients and orthopaedic surgeons reflected high satisfaction rates with care provided, noting minimal communication and clinical barriers compared to face-to-face consultations. Whilst not without limitations, our protocol allowed for rapid adoption of telemedicine in line with a national-wide initiative to digitize healthcare. DISCUSSION: The implementation of teleconsultation services at our orthopaedic centre has provided an effective method of healthcare delivery while enforcing social distancing measures - which proves vital in combating the spread of COVID-19 and ushering in a new normal.

SARS-CoV-2 in migrant worker dormitories: Geospatial epidemiology supporting outbreak management.

BACKGROUND: Migrant worker dormitories-residential complexes where 10-24 workers share living spaces-account for the majority of cases of SARS-CoV-2 infection in Singapore. To prevent overspill of transmission to the wider population, starting in early April 2020, residents were confined to their dormitories while measures were put in place to arrest the spread of infection. This descriptive study presents epidemiological data for a population of more than 60 000 migrant workers living in two barracks-style and four apartment-style dormitories located in western Singapore from April 3 to June 10, 2020. METHODS: Our report draws from data obtained over the first 50 days of outbreak management in order to describe SARS-CoV-2 transmission in high-density housing environments. Cumulative counts of SARS-CoV-2 cases and numbers of housing units affected were analyzed to report the harmonic means of harmonic means of doubling times and their 95% confidence intervals (CI). RESULTS: Multiple transmission peaks were identified involving at least 5467 cases of SARS-CoV-2 infection across six dormitories. Our geospatial heat maps gave an early indication of outbreak severity in affected buildings. We found that the number of cases of SARS-CoV-2 infection doubled every 1.56 days (95% CI 1.29-1.96) in barracks-style buildings. The corresponding doubling time for apartment-style buildings was 2.65 days (95% CI 2.01-3.87). CONCLUSIONS: Geospatial epidemiology was useful in shaping outbreak management strategies in dormitories. Our results indicate that building design plays an integral role in transmission and should be considered in the prevention of future outbreaks.

Interpretation of hip fracture patterns using areal bone mineral density in the proximal femur.

INTRODUCTION: Bone mineral density scans are currently interpreted based on an average score of the entire proximal femur. Improvements in technology now allow us to measure bone density in specific regions of the proximal femur. The study attempts to explain the pathophysiology of neck of femur (NOF) and intertrochanteric/basi-cervical (IT) fractures by correlating areal BMD (aBMD) scores with fracture patterns, and explore possible predictors for these fracture patterns. MATERIALS AND METHODS: This is a single institution retrospective study on all patients who underwent hip surgeries from June 2010 to August 2012. A total of 106 patients (44 IT/basi-cervical, 62 NOF fractures) were studied. The data retrieved include patient characteristics and aBMD scores measured at different regions of the contralateral hip within 1 month of the injury. Demographic and clinical characteristic differences between IT and NOF fractures were analyzed using Fisher's Exact test and two-sample t test. Relationship between aBMD scores and fracture patterns was assessed using multivariable regression modeling. RESULTS: After adjusted multivariable analysis, T-Troc and T-inter scores were significantly lower in intertrochanteric/basi-cervical fractures compared to neck of femur fractures (P = 0.022 and P = 0.026, respectively). Both intertrochanteric/basi-cervical fractures (mean T.Tot -1.99) and neck of femur fractures (mean T.Tot -1.64) were not found to be associated with a mean T.tot less than -2.5. However, the mean aBMD scores were consistently less than -2.5 for both intertrochanteric/basi-cervical fractures and neck of femur fractures. Gender and calcium intake at the time of injury were associated with specific hip fracture patterns (P = 0.002 and P = 0.011, respectively). CONCLUSIONS: Hip fracture patterns following low energy trauma may be influenced by the pattern of reduced bone density in different areas of the hip. Intertrochanteric/basi-cervical fractures were associated with significantly lower T-Troc and T-Inter scores compared to neck of femur fractures, suggesting that the fracture traversed through the areas with the lowest bone density in the proximal femur. In the absence of reduced T.Troc and T.Inter, neck of femur fractures occurred more commonly. T-Total scores may underestimate the severity of osteoporosis/osteopenia and measuring T-score at the neck of femur may better reflect the severity of osteoporosis and likelihood of a fragility fracture.

Reamer Irrigator Aspirator bone graft harvesting: complications and outcomes in an Asian population.

INTRODUCTION: Autologous bone grafting has been accepted as the gold standard in the treatment of non-unions and in definitive filling of segmental bone defects. However, there have been well-recognised complications associated with their harvest. The Reamer Irrigator Aspirator (RIA) system is an alternative technique of autologous bone graft harvesting. Studies have been published in the Western population showing the efficacy and outcome of this technique. No prior studies were done in the Asian population, who has smaller average canals, different femoral geometry as compared to Caucasians and weaker bone density in both genders. We aim to present the findings and discuss its suitability in the Asian population when dealing with segmental bone loss and non-unions requiring reconstruction. METHODS: We conducted a retrospective analysis of all trauma patients with segmental bone loss and non-unions treated with RIA bone grafting over a 4.5 year period. A total of 57 cases of RIA bone grafting were conducted on 53 patients. The amount of bone graft harvested, blood loss and post-operative pain were measured. Patients were followed up for union rate as well as complications of the procedure. RESULTS: Union was achieved in 86.8% of patients. The mean time to union was 17.64 weeks. Seven patients did not achieve union after the first RIA surgery, in which six of seven were open fractures initially and six were smokers. One major intra-operative complication was recorded, that being a fractured femoral shaft due to thinning of the cortex by the RIA harvester. There were two patients who developed donor site superficial soft tissue infection that resolved after a course of antibiotics. There were no long-term complications seen in all patients. CONCLUSIONS: The safety and efficacy of RIA bone graft harvesting for the management of non-union in the Asian population is promising, with adequate graft quantities, high success and low complication rates that are comparable to the Caucasian population. The diameter of the medullary canal in our population is suitable for this procedure. We believe that RIA bone graft harvesting provides a reliable and safe alternative source of autologous bone grafts for bone grafting of non-union sites.

Proximal femoral locking compression plate for proximal femoral fractures.

PURPOSE: To review short-term outcomes of proximal femoral locking compression plate (PF-LCP) fixation for proximal femoral fractures in terms of postoperative complications and failure rates. METHODS: Medical records of 21 men and 5 women aged 22 to 85 (mean, 49.7) years who underwent internal fixation with the PF-LCP for proximal femoral fractures were reviewed. Younger patients (mean age, 38.7 years) were more commonly involved in high-energy trauma with multiple musculoskeletal injuries, whereas older patients (mean age, 67.7 years) were more commonly involved in low-energy trauma. Fractures were classified into: multi-fragmentary pertrochanteric fractures (n=13), transtrochanteric fractures (n=6), and subtrochanteric/proximal diaphyseal fractures (n=7). RESULTS: Patients were followed up for a mean of 14.7 months. Seven patients developed complications including loosening of locking screws (n=4), delayed union (n=2), and infection (n=1); 4 of them required additional surgeries. CONCLUSION: The PF-LCP is appropriate for complex proximal femoral fractures with poor bone quality, revision surgeries, and multi-fragmentary subtrochanteric/proximal diaphyseal fractures. For intertrochanteric fractures, the sliding hip screw system should be used to avoid failure.

Early versus late flap coverage for open tibial fractures.

PURPOSE: To compare early versus late flap coverage for open tibial fractures. METHODS: Medical records of 83 men and 6 women (mean age, 38 years) who underwent fixation for open tibial fractures (Gustilo grades IIIB and IIIC) followed by flap coverage within (n=30) or after (n=59) 72 hours were reviewed. All fractures were treated within 24 hours. Outcome measures included bone union, infection, flap failure, the need for secondary procedures to achieve union, and eventual amputation. The early and late flap coverage groups were compared. RESULTS: Early flap coverage was associated with shorter length of hospitalisation (31.4 vs. 55.8 days, p<0.01), lower deep infection rates (23% vs. 54%, p<0.01), and smaller number of surgical procedures (6.4 vs. 9.2, p=0.01). The 2 groups did not differ significantly in terms of the time to bone union, flap failure, amputation, and the need of secondary procedures to facilitate bone union. CONCLUSION: In severe open tibial fractures, early soft-tissue coverage (within 72 hours) was associated with more favourable outcomes in terms of length of hospitalisation and infection.

Image-driven haptic simulation of arthroscopic surgery.

Virtual haptic simulation of minimally invasive arthroscopic surgery becomes an extremely important training tool that allows the medical students to acquire necessary motor skills before they can approach actual patients. Normally, 3D simulation of the interior of a joint requires significant efforts from the software developers but yet remains not always photo realistic. In this paper, we propose a pioneering approach of using augmented real arthroscopic images for realistic and immersive image-driven visualization and haptic interaction within the surgical field as if it were actual three-dimensional scene where body parts displayed in the image act and feel as real 3D objects rather than their images.

Trans-iliosacral plating for vertically unstable fractures of sacral spine associated with spinopelvic dissociation: A cadaveric study.

BACKGROUND: The treatment algorithm for sacral fracture associated with vertical shear pelvic fracture has not emerged. Our aim was to study a new approach of fixation for comminuted and vertically unstable fracture pattern with spinopelvic dissociation to overcome inconsistent outcome and avoid complications associated with fixations. We propose fixation with well-contoured thick reconstruction plate spreading across sacrum from one iliac bone to another with fixation points in iliac wing, sacral ala and sacral pedicle on either side. Present biomechanical study tests the four fixation pattern to compare their stiffness to vertical compressive forces. MATERIALS AND METHODS: Dissection was performed on human cadavers through posterior midline paraspinal approach elevating erector spinae from insertion with two flaps. Feasibility of surgical exposure and placement of contoured plate for fixation was evaluated. Ten age and sex matched computed tomography scans of pelvis with both hips were obtained. Reconstructions were performed with advantage windows 4.2 (GE Light Speed QX/I, General Electric, Milwaukee, WI, USA). Using the annotation tools, direct digital CT measurement (0.6 mm increments) of three linear parameters was carried out. Readings were recorded at S2 sacral level. Pelvic CT scans were extensively studied for entry point, trajectory and estimated length for screw placement in S2 pedicle, sacral ala and iliac wing. Readings were recorded for desired angulation of screw in iliac wing ala of sacrum and sacral pedicle with respect to midline. The readings were analyzed by the values of mean and standard deviation. Biomechanical efficacy of fixation methods was studied separately on synthetic bone. Four fixation patterns given below were tested to compare their stiffness to vertical compressive forces: 1) Single S1 iliosacral screw (7.5 mm cancellous screw), 2) Two S1 and S2 iliosacral screws, 3) Isolated trans-iliosacral plate, 4) Trans-iliosacral plate + single S1 iliosacral screw. STATISTICAL ANALYSIS: Mean of desired angulation for inserting screws and percentage of displacement on biomechanical testing was evaluated. RESULTS: Mean angulations for inserting sacral pedicel were 12.3° (SD 2.7°) convergent to midline and divergent of 14° (SD 2.3°) for sacral ala screw and 23° (SD 4.9°) for iliac wing screw. All screws needed to be inserted at an angle of 90° to sacral dorsum to avoid violation of root canals. Cross headed displacement across fracture site was measured and plotted against the applied vertical shear load of 300 N in five cycles each for all the four configurations. Also, the force required for cross headed displacement of 2.5 mm and 5 mm was recorded for all configurations. Transmitted load across both ischial tuberosities was measured to resolve unequal distribution of forces. Taking one screw construct (configuration 1) as standard base reference, trans-iliosacral plate construct (configuration 3) showed equal rigidity to standard reference. Two screw construct (configuration 2) was 12% stronger and trans-iliosacral plate (configuration 4) with screw was 9% stronger at 2.5 mm displacing on 300 N force, while it showed 30% and 6%, respectively, at 5 mm cross-headed displacement. CONCLUSIONS: Trans-iliosacral plating is feasible anatomically, biomechanically and radiologically for sacral fractures associated with vertical shear pelvic fractures. Low profile of plate reduces the risk of hardware prominence and decreases the need for implant removal. Also, the fixation pattern of plate allows to spare mobile lumbosacral junction which is an important segment for spinal mobility. Biomechanical studies revealed that rigidity offered by plate for cross headed displacement across fracture site is equal to sacroiliac screws and further rigidity of construct can be increased with addition of one more screw. There is need for precountered thicker plate in future.

Epidemiological analysis of outcomes in 323 open tibial diaphyseal fractures: a nine-year experience.

INTRODUCTION: Open fractures of the tibia pose a challenge to orthopaedic and plastic surgeons. A retrospective observational review was conducted to evaluate the epidemiological factors and fracture outcomes in the Singapore context. METHODS: A nine-year period of open tibial shaft fractures presenting to our institution was reviewed. Demographic and management data were recorded. Statistical analysis was performed on the outcomes of length of hospital stay, number of operations, time to union and infection rates. RESULTS: 323 fractures met our inclusion criteria (Gustilo [G] 1=53, G2=100, G3=170). Mean age of patients was 36.5 years, 91.3% were male and 40.9% were non-Singaporeans. 69.3% of fractures occurred from road traffic accidents and 21.7% from industrial accidents. Mean length of hospital stay was 28.7 days and number of operations was 4.29. Time to union was 10.7 months and overall infection rate was 20.7%. Infection rates were significantly higher in G3b/G3c compared to G3a (45.7% vs. 21.1%) patients. There was no significant reduction in infection rates when open tibial fractures were operated on within six hours of admission. Multiple injured patients required a longer time to union and hospital stay. There was an exponential cost increase with greater severity of fracture. CONCLUSION: High Gustilo and AO classification injuries positively correlate with high non-union and infection rates, requiring multiple operations and long hospital stay. There is no benefit in performing surgery on open tibial fractures within six hours of presentation. A significant proportion of these patients would be polytraumatised, indirectly affecting fracture union.

Minimally invasive helical plating for shaft of humerus fractures: technique and outcome.

INTRODUCTION: The humerus is subjected to substantial amount of torsional stress. Conventional plating may not address this sufficiently and may lead to fixation failure or non-union. A helical plate may offer the solution. We present the surgical technique and functional outcome of 5 cases of humeral shaft fractures treated with this technique in a minimally invasive way. MATERIALS AND METHODS: The operations were performed between 2004 and 2010, by three surgeons. All the patients had closed humeral shaft fractures, either simple transverse or with mild comminution. Two small incisions were made. The proximal incision was placed along the deltopectoral groove over the shaft, and the distal incision was placed as in an antero-lateral approach. The radial nerve was identified and protected. A pre-selected plate was contoured and introduced in the submuscular plane. The plate was placed in a proximal-lateral and distal-anterior position. Screws were inserted through stab incisions. The patients were followed for an average of 6 months. Functional recovery of the shoulder and elbow was assessed using the Constant and Mayo elbow performance score systems. RESULTS: All incisions healed by first intention without complications and all the fractures went on to unite. All patients achieved good to excellent shoulder and elbow function. CONCLUSION: The helical plate technique is a safe and effective method of treating humeral shaft fractures and has good functional outcome.

Demographics and clinical presentation of slipped capital femoral epiphysis in Singapore: comparing the East with the West.

This study examines the demographics and clinical presentation of slipped capital femoral epiphysis in Singapore. Sixty-six patients (53 boys, 13 girls) with 77 involved hips were reviewed retrospectively. Local prevalence was 1.2/100,000 children. Twenty-four patients were Chinese, 12 were Malay, 27 were Indians, and three patients were Eurasians. A total of 76.6% of patients above the 90th percentile for body weight were present; 16.7% of patients had bilateral involvement. Seventeen patients had endocrine-related problems. We had a high male preponderance, and a disproportionately high number of Indian patients. A high proportion of patients were obese. Our incidence of bilateral involvement seems to be higher than our Indonesian neighbors. The differences seen may be due to genetic and sociocultural variations.