Sabarul Afian Mokhtar

Effects of calcium supplements on fracture healing in a rat osteoporotic model

Fracture healing is a complex process, which is further complicated if the bone is osteoporotic. Calcium is one of the important minerals in bone and has been found to prevent osteoporosis but its role in fracture healing of osteoporotic bone is still unclear. We carried out a study on the effects of calcium supplementation on the late phase healing of fractured osteoporotic bone using an ovariectomized rat model. Twenty‐four female Sprague–Dawley rats were divided into three groups: sham‐operated (SO), ovariectomized‐control (OVXC), and ovariectomized + calcium supplements (Ca). The right femurs of all the rats were fractured at mid‐epiphysis and a K‐wire was inserted for internal fixation. After 2 months of treatment, the rats were sacrificed and the femora were dissected out for radiological and biomechanical assessment. As expected, osteoporosis resulted in impaired healing as shown by the poor radiological and biomechanical properties of the OVXC group. CT scans showed significantly lower callus volumes in the SO and Ca groups compared to the OVXC group. Radiological scoring of fracture healing and callus staging of the SO and Ca groups were better than the OVXC group. However, the biomechanical parameters of the Ca group were significantly lower than the SO group and similar to the OVXC group. Therefore, calcium supplements may appear to improve fracture healing of osteoporotic bone but failed to improve strength.

Effects of α-tocopherol on the early phase of osteoporotic fracture healing.

Fracture healing is a complex process, which is more complicated if the bone is osteoporotic. One of the vitamin E isomers, α‐tocopherol, has been found to prevent osteoporosis and improve bone fracture healing but its role in the healing of osteoporotic fractures is still unclear. We carried out a study on the effects of α‐tocopherol supplementation on osteoporotic fracture healing using an ovariectomized rat model, whereby we focused on the early phase of fracture healing, that is, the phase with excessive production of free radicals. Twenty‐four female Sprague–Dawley rats were divided into three groups: sham‐operated (SO), ovariectomized–control (OVC), and ovariectomized + α‐tocopherol supplementation (ATF) groups. The right femora of all the rats were fractured at mid‐diaphysis and K‐wires were inserted for internal fixation. After 2 weeks of treatment, the rats were euthanized and the femora were dissected out for measurement of callous volume by CT‐scan and radiological staging of callous formation and fracture healing. The oxidative parameters of the fractured femora were also measured. The results showed that the callous volume and callous staging were not different between the groups. However, the fracture healing stage of the OVC group was lower than the SO group, while α‐tocopherol supplementation in the ATF group had improved the healing until it was comparable to the SO group. The activities of the anti‐oxidatant enzymes, superoxide dismutase, and glutathione peroxidase in the ATF group were found to be significantly higher than in the OVC group. In conclusion, α‐tocopherol improved fracture healing but had no effect on the callous volume and staging. The improvement in fracture healing may be due to the increased activities of the anti‐oxidatant enzymes in the bone during the early phase of fracture healing of osteoporotic bone. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1732–1738, 2011

The effects of alpha-tocopherol supplementation on fracture healing in a postmenopausal osteoporotic rat model

OBJECTIVE: Osteoporosis increases the risk of bone fractures and may impair fracture healing. The aim of this study was to investigate whether alpha-tocopherol can improve the late-phase fracture healing of osteoporotic bones in ovariectomized rats. METHOD: In total, 24 female Sprague-Dawley rats were divided into three groups. The first group was sham-operated, and the other two groups were ovariectomized. After two months, the right femora of the rats were fractured under anesthesia and internally repaired with K-wires. The sham-operated and ovariectomized control rat groups were administered olive oil (a vehicle), whereas 60 mg/kg of alpha-tocopherol was administered via oral gavage to the alpha-tocopherol group for six days per week over the course of 8 weeks. The rats were sacrificed, and the femora were dissected out. Computed tomography scans and X-rays were performed to assess fracture healing and callus staging, followed by the assessment of callus strengths through the biomechanical testing of the bones. RESULTS: Significantly higher callus volume and callus staging were observed in the ovariectomized control group compared with the sham-operated and alpha-tocopherol groups. The ovariectomized control group also had significantly lower fracture healing scores than the sham-operated group. There were no differences between the alpha-tocopherol and sham-operated groups with respect to the above parameters. The healed femora of the ovariectomized control group demonstrated significantly lower load and strain parameters than the healed femora of the sham-operated group. Alpha-tocopherol supplementation was not able to restore these biomechanical properties. CONCLUSION: Alpha-tocopherol supplementation appeared to promote bone fracture healing in osteoporotic rats but failed to restore the strength of the fractured bone.

Tocotrienol Supplementation Improves Late-Phase Fracture Healing Compared to Alpha-Tocopherol in a Rat Model of Postmenopausal Osteoporosis: A Biomechanical Evaluation

This study investigated the effects of α-tocopherol and palm oil tocotrienol supplementations on bone fracture healing in postmenopausal osteoporosis rats. 32 female Sprague-Dawley rats were divided into four groups. The first group was sham operated (SO), while the others were ovariectomised. After 2 months, the right femora were fractured under anesthesia and fixed with K-wire. The SO and ovariectomised-control rats (OVXC) were given olive oil (vehicle), while both the alpha-tocopherol (ATF) and tocotrienol-enriched fraction (TEF) groups were given alpha-tocopherol and tocotrienol-enriched fraction, respectively, at the dose of 60 mg/kg via oral gavages 6 days per week for 8 weeks. The rats were then euthanized and the femora dissected out for bone biomechanical testing to assess their strength. The callous of the TEF group had significantly higher stress parameter than the SO and OVXC groups. Only the SO group showed significantly higher strain parameter compared to the other treatment groups. The load parameter of the OVXC and ATF groups was significantly lower than the SO group. There was no significant difference in the Youngs modulus between the groups. In conclusion, tocotrienol is better than α-tocopherol in improving the biomechanical properties of the fracture callous in postmenopausal osteoporosis rat model.

Activities of Daily Living and Determinant Factors among Older Adult Subjects with Lower Body Fracture after Discharge from Hospital: A Prospective Study

Fracture is a type of musculoskeletal injury that contributes to an inability to perform daily activities. The objective of this study was to evaluate activities of daily living (ADL) of older adult patients with lower body fracture and to determine factors influencing ADL. Patient’s ADL was assessed at pre-fracture, ward admission and post-discharge phases using the Katz ADL questionnaire. There were 129 subjects at pre-fracture and ward phases and 89 subjects at discharge phase. There were four independent variables; age, gender, type of fracture and ability to walk before fracture. Logistic regression models showed that ‘age’ and ‘ability to walk before fracture’ were the determinant factors of dependent for ‘bathing’, ‘dressing’ and ‘toileting’. The ‘ability to walk before fracture’ was the determinant factor of dependent for ‘transferring’. ‘Age’ and ‘gender’ were the determinant factors of dependent for ‘continence’, while ‘age’ was the determinant factor of dependent for ‘feeding’. The ADL score changes were significant across the phases with a reduction in ADL score in the ward admission phase and partial increment during the post-discharge phase. There were improvements in the health outcomes of subjects aged more than 50 years old after 3 months of being discharged from the hospital. In conclusion, age, being female, having a hip fracture and using a walking aid before fracture were the determinants identified in this study.

Lumbar kinematics, functional disability and fear avoidance beliefs among adults with nonspecific chronic low back pain

OBJECTIVES This study aimed to examine correlations between lumbar kinematics, functional disability and fear avoidance beliefs among adults with nonspecific chronic low back pain (LBP). METHODS This cross-sectional study was conducted between March and December 2014. A total of 32 adults diagnosed with nonspecific chronic LBP were recruited from outpatients attending either an orthopaedic clinic at a university hospital or a private physiotherapy clinic in Malaysia. Lumbar kinematics were measured using sensors attached at the first lumbar (L1) and second sacral (S2) vertebrae levels. The Oswestry Disability Index (ODI) and Fear-Avoidance Beliefs Questionnaire (FABQ) were used to assess degree of functional disability and fear avoidance beliefs, respectively. RESULTS For maximum range of motion, positive correlations were observed between ODI scores and right lateral flexion and right rotation (P = 0.01 each), although there was a negative correlation with left rotation (P = 0.03). With maximum angular velocity, ODI scores were positively correlated with right and left lateral flexion L1 (P = 0.01 and <0.01, respectively) but negatively correlated with left lateral flexion L2 (P = 0.04). Regarding minimum angular velocity, ODI scores were positively correlated with left lateral flexion S2 (P <0.01) but negatively correlated with right and left lateral flexion L1 (P = 0.02 each), right rotation L1 (P = 0.02) and left rotation S2 (P = 0.01). No significant correlations were found between lumbar kinematics and FABQ scores. CONCLUSION These findings suggest that certain lumbar kinematic parameters are correlated with functional disability, but not with fear avoidance beliefs.

Effects of Eurycoma Longifolia on Fracture Healing of Androgen-Deficient Osteoporosis Model: A Micro Computed Tomograph Analysis

Micro computed tomography (micro-CT) imaging is a useful tool to monitor fracture healing in osteoporosis model. It creates a 3-D image of the fracture callus which can be analysed to assess bone parameters quantitatively. In this study, micro-CT was used to assess the fracture healing of orchidectomised rats, an androgen-deficient osteoporosis model. The effects of Eurycoma longifolia, a medicinal plant with pro-androgenic effects, on fracture healing were assessed. The rats were grouped into orchidectomised-control (ORX), sham-operated (SHAM), orchidectomised and injected with testosterone intramuscularly once weekly (TEN) and orchidectomised and daily oral gavage of Eurycoma longifolia (EL). Treatment duration was six weeks following bone fracture. Fracture was induced in the right tibia of all the rats. A total of 100 axial slices above and below fracture line were scanned with a micro-CT. The micro-CT analysis was able to detect significant difference in the fracture healing rate of ORX and TEN groups. The bridging cortices and fraction of mineralized tissue of the bridging cortices of the callous of ORX group was significantly lower than TEN group. No significant micro-CT changes were seen in the fracture healing of the EL group. The effect of EL on fracture healing was not demonstrable in orchidectomised rat model.