Prevalence of osteoporosis in spinal cord injury

 

 

Abstract              Background: Osteoporosis is a chronic metabolic bone disease-related to various factors including menopause, old age, less physical activities, prolonged bedridden patients, spinal cord injuries etc. About 200 million people had been affected worldwide due to osteoporosis. Osteoporosis has affected nearly 50 million Indians. Numerous clinical series have reported a high incidence ranging from 1 to 34%of lower extremities fractures in spinal cord injuries. The pathogenesis of osteoporosis after SCI remains complex and perplexing. Disuse may play an important role in the pathogenesis of osteoporosis, but neural factors also appear to be important. Our aim of study to measure the prevalence of osteoporosis in SCI patients who attended outpatient clinic in government institute of rehabilitation medicine during June 2019.

Key Word: osteoporosis, spinal cord injury.

 

INTRODUCTION

Bone loss is a common complication in spinal cord injury patients.¹ Reduced muscular activity and mechanical loading causing reduction in bone mineral density after a spinal cord injury. The rate of bone loss is rapid and linear in acute stages which stabilize in one to two years post injury.² The loss of bone mineral density is found to be more in the lower limbs than the upper limbs. The fracture risk is closely related to bone mineral density.³

 

MATERIALS AND METHODS

Participants and study design

Cross sectional study conducted with 30 participants with traumatic spinal cord injury who attended OPD between June 2019 at Government Institute of Rehabilitation Medicine, Chennai were included in the study. Inclusion criteria: Age 18 to 60 years, both sexes, duration of injury >5 years, ASIA A or B as per American Spinal Injury Association Impairment Scale. Exclusion criteria: duration of injury <5 years, not willing to participate in the study, heterotopic ossification.

METHODOLOGY

Demographic details collected: age, sex, duration of injury, level of injury, medication history, history of fracture after the spinal cord injury, rehabilitation details. Informed consent was obtained. All participants were made to undergo Dual Energy X-ray absorptiometry of femoral neck and hip on the non- dominant side. The procedure of the scan was done as per The international society of Clinical Densitometry guidelines. The bone mineral density was measured in g/cm.²

 

RESULTS

A total of 30 spinal cord injury patients participated in the study which includes 22 males(73.33%) and 8 females(26.67%). The mean age of the males was 43.6 years and that of females was 47.8 years. The level of injury was cervical- 9 (30%), thoracic- 16 (55.33%) and lumbar- 5 (16.67%) with 8(26.67%) participants on ASIA A level and 22(73.33%) on ASIA B level. The duration of injury was 5-10 years for 23(76.67%) participants and >10years for 7 (23.33%) participants. 26(86.66%) of the population was taking calcium supplements, 5(16.66%) were taking Vitamin D supplements and 2(6.67%) were taking bisphosphonates. 1 participant reported history of fracture of tibia and 2 reported fracture neck of femur.

Table 1

 

The mean bone mineral density in hip was 0.560 in males and 0.495 in females. The mean BMD in neck of femur was 0.515 in males and 0.469 in females. Mean Z score in hip was -2.51 in males and -2.78 in females. The mean Z score in neck of femur was -2.05 in males and -2.02 in females

Table 2

 

DISCUSSION

Pathogenesis of loss of bone mineral density is due to hormonal causes, aging and reduced physical activity. Coupaud et al. have found a more reduction in BMD in women after spinal cord injury.⁴ A study by Slade et al. concluded that the effect of spinal cord injury on bone mineral density was higher than that of estrogen loss due to menopause.⁵ Absence of weight bearing activities is found to play a major role in loss of bone mineral density in motor complete paraplegics below the level of spinal cord injury.⁶ Disturbances in autonomic nervous system with altered sympathetic activity also lead to accentuated bone loss.⁷ As the bone mineral density decreases the capacity to preserve the bone integrity during mechanical loading reduces.⁸ The bone mineral density loss is more prominent in femur and tibia, the fracture risks are higher at these sites.^9,10,11 The most common circumstances when fractures occur were falls from wheelchair during transfers.^10,11 Previous studies have shown incidence of fractures in spinal cord injuries is 10-34%.^11,12 The fracture risk was higher in women in non spinal cord injury individuals.^13,14 Carbone et al. showed a significant association between lower limb fractures in spinal cord injury more than 2 years duration¹⁵ The fracture incidence did not show significant difference between the sexes in spinal cord injury patients. The bone loss was more in the female participants when compared with the male. Osteoporosis and fractures increase the morbidity and mortality in spinal cord injury patients. Fracture management is challenging in this population and increase occurrence the complications like deep vein thrombosis, pressure ulcers and increased risk of surgery related complications. Addressing the bone health with medical management, physical therapy and reducing fall incidence is of paramount importance in preventing osteoporosis and bone related complications

The Z score

 

LIMITATIONS

Small sample size. Further study with larger sample size including bone mineral density evaluation at tibia should be done. There was no control group of the same age group.

 

CONCLUSION

The bone mineral density was found to be lower in spinal cord injury patients. Addressing the bone health with medical management, physical therapy and reducing fall incidence is of paramount importance in preventing osteoporosis and bone related complications. The need of patient education and development of protocols to treat and prevent osteoporosis in spinal cord injury as a part of rehabilitation program is reemphasized by the study.

 

REFERENCES

1. Biering-Sorensen F, Bohr HH, Schaadt OP. Longitudinal study of bone mineral content in the lumbar spine, the forearm and the lower extremities after spinal cord injury. Eur J Clin Investig. 1990;20:330–5
2. Eser P, Frotzler A, Zehnder Y, Wick L, Knecht H, Denoth J, et al. Relationship between the duration of paralysis and bone structure: a pQCT study of spinal cord injured individuals. Bone. 2004;34:869–80
3. Zehnder Y, Luthi M, Michel D, Knecht H, Perrelet R, Neto I, et al. Long-term changes in bone metabolism, bone mineral density, quantitative ultrasound parameters, and fracture incidence after spinal cord injury: a cross-sectional observational study in 100 paraplegic men. Osteoporos Int. 2004;15:180–9
4. Coupaud S, McLean AN, Allan DB. Role of peripheral quantitative computed tomography in identifying disuse osteoporosis in paraplegia. Skelet Radio. 2009;38:989–95
5. Slade JM, Bickel CS, Modlesky CM, Majumdar S, Dudley GA. Trabecular bone is more deteriorated in spinal cord injured versus estrogen-free postmenopausal women. Osteoporos Int. 2005;16:263–72
6. Amin S. Mechanical factors and bone health: effects of weightlessness and neurologic injury. Curr Rheumatol Rep. 2010;12:170–6
7. He JY, Jiang LS, Dai LY. The roles of the sympathetic nervous system in osteoporotic diseases: a review of experimental and clinical studies. Ageing Res Rev. 2011;10:253–63
8. Jarvinen TL, Michaelsson K, Aspenberg P, Sievanen H. Osteoporosis: the emperor has no clothes. J Intern Med. 2015;277:662–73
9. Akhigbe T, Chin AS, Svircev JN, Hoenig H, Burns SP, Weaver FM, et al. A retrospective review of lower extremity fracture care in patients with spinal cord injury. J Spinal Cord Med. 2015;38:2–9
10. Frotzler A, Cheikh-Sarraf B, Pourtehrani M, Krebs J, Lippuner K. Long-bone fractures in persons with spinal cord injury. Spinal Cord. 2015;53:701–4
11. Gifre L, Vidal J, Carrasco J, Portell E, Puig J, Monegal A, et al. Incidence of skeletal fractures after traumatic spinal cord injury: a 10-year follow-up study. Clin Rehabil. 2014;28:361–9
12. Lazo MG, Shirazi P, Sam M, Giobbie-Hurder A, Blacconiere MJ, Muppidi M. Osteoporosis and risk of fracture in men with spinal cord injury. Spinal Cord. 2001;39:208–14
13. Riggs BL, Melton Iii LJ 3rd, Robb RA, Camp JJ, Atkinson EJ, Peterson JM, et al. Population-based study of age and sex differences in bone volumetric density, size, geometry, and structure at different skeletal sites. J Bone Min Res. 2004;19:1945–54
14. Nicks KM, Amin S, Atkinson EJ, Riggs BL, Melton LJ 3rd, Khosla S. Relationship of age to bone microstructure independent of areal bone mineral density. J Bone Min Res. 2012;27:637–44
15. Carbone LD, Chin AS, Burns SP, Svircev JN, Hoenig H, Heggeness M, et al. Mortality after lower extremity fractures in men with spinal cord injury. J Bone Min Res. 2014;29:432–9.

 

 

 

 

 

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