musculoskeletal tissues show increased bone fragility , loss of cartilage resilience , reduced ligament elasticity , loss of muscular strength , and fat redistribution decreasing the ability of the tissues to carry out their normal functions .
the loss of mobility and physical independence resulting from arthropathies and fractures can be particularly devastating in this population , not just physically and psychologically , but also in terms of increased mortality rates .
the aim of this article is to present some of the most frequent musculoskeletal disorders of the elderly , including some misleading presentations .
we used the following terms and some of its combinations : elderly , aged , epidemiology , fracture , osteoporosis , vertebral , hip , pelvis , arthritis , neoplasm , malignancy , myeloma , paget , gout , infection , microcrystal , and radiology .
articles without english abstracts were excluded . besides , certain relevant rheumatological , orthopedic , and radiological books were also used .
fractures are frequent in the elderly and result mainly from the effects of falls and osteoporosis .
low - impact falls , even from standing height , are the most common cause of injury in geriatric patients . falling is a multi - factorial problem due to both extrinsic ( e.g. , environmental and housing conditions ) and intrinsic risk factors ( e.g. , impaired mobility , loss of muscular strength , poor visual acuity , and medication , for instance corticoids).[46 ] osteoporosis , which is characterized by qualitatively normal , but quantitatively deficient bone , leads to bone fragility and increased risk of fractures .
the general prevalence of osteoporosis in women is approximately 50% at the age of 85 years , while in men the prevalence is about 20% at that age .
ethnic differences also exist : mineral bone density is higher in black women and lower in asian women , while in white women evidence shows an intermediate value .
due to its precision , the most widely used quantitative technique is dual energy x - ray absorptiometry , which makes it possible to diagnose osteoporosis early , predict the risk of fracture , determine therapeutic intervention , and monitor response to treatment . this method grades bone loss according to standard deviations ( sd ) from the mean young adult value .
a value less than 2.5 times the sd below the young adult mean , is considered to indicate osteoporosis .
the main radiographic features of osteoporosis are increased radiolucency and cortical thinning , mainly in the spine , giving rise to a well - demarcated outline of the vertebral body , which has been described as , 
picture framing. besides , in the spine , an increased biconcavity of the vertebral end plates , with a protrusion of the intervertebral disk into the vertebral body can be observed .
however , early radiographic changes are subtle , as a bone loss of approximately 30% must occur before it can be detected .
vertebral compression fractures are the most common osteoporotic fractures , with a greater incidence in women over 60 years of age .
they can be observed in up to 25% of women over 70 years of age and 40% of those over 80 years .
after one episode , the risk of subsequent vertebral fracture increases at least four - fold , with substantially increased rates during the first year . these fractures are associated with higher mortality and significant morbidity , even though they are afforded little clinical attention .
they often appear as multiple fractures with anterior wedging , and may be associated with significant deformity , leading to kyphosis .
they are usually well demonstrated on radiographs , but can be better assessed with computed tomography ( ct ) or magnetic resonance ( mr ) imaging , when necessary .
the latter imaging modality may be indicated in case of associated neurological symptoms  a rare event  or when a vertebroplasty is discussed , in order to better localize the recently fractured vertebra .
vertebral compression fractures in the elderly may involve several problems : first is differentiating between osteoporotic and malignant vertebral collapse ( vc ) , particularly metastatic vc , as the latter is by far the most common malignant tumor affecting the skeleton in the elderly . in most patients ,
multiple , relatively symmetrical thoracolumbar vcs , associated with diffuse increased radiolucency are suggestive of osteoporosis [ figure 1a ] .
the whole vertebral endplate is impacted , sometimes in association with increased or decreased radiolucency of the subjacent trabecular bone ( band - like distribution of the abnormalities under the fractured vertebral end plate ) .
gas can also be seen under the fracture and is nearly pathognomonic of the benign nature of the collapse .
there is no cortical osteolysis , although fractures can be identified with retropulsion of a bone fragment .
conversely , the following are a cause for concern : a single vc , involvement of the cervical spine , heterogeneous increased or decreased radiolucency that can not be explained by an underlying end plate fracture , a focal collapse ( on the ap or lateral view ) , or a bulging of the vertebral body or cortical osteolysis [ figure 1b ] . if in doubt or for a better assessment of the spinal canal and soft tissue , ct , or better yet , an mri can be performed , in order to differentiate between these two disorders . in benign fractures ,
an mri may show a band distribution of abnormal signal intensities on t1 and t2 weighted images , spared normal bone marrow signal intensity , retropulsion of a posterior bone fragment , and multiple compression fractures ; on the contrary , signs such as a convex posterior border of the vertebral body , abnormal signal intensity of the posterior elements , an epidural mass or a focal paraspinal mass are suggestive of spinal metastasis.[1921 ] second , vertebral fractures can be missed following moderate trauma , because the fracture may be difficult to identify in an osteoporotic radiolucent bone and / or because the pain is attributed to another painful condition , such as degenerative changes .
this is observed in particular in the cervical spine , particularly at c2 , and may lead to secondary neurological complications [ figure 2 ] .
ankylosis may be related to ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis , which especially affect males and they have an estimated frequency of 5 to 15% in the elderly.[2225 ] these ankylosed spines become increasingly susceptible to injury , even in the event of low - energy impacts , and are prone to unstable vertebral fractures with an increased frequency of neurological complications , either primary or secondary , after unprotected transfers and manipulation .
these lesions may be missed on plain films when non - displaced or mildly displaced , especially in hyperextension , whereas , they are well demonstrated on ct or mr imaging . however
, the mri features can sometimes be misleading and mimic infectious spondylitis when signal abnormalities of the disco - vertebral junction are present .
caution is required when an elderly patient presents with an ankylosed spine , minor trauma or acute pain , especially if signal abnormalities of the anterior and posterior spine are observed [ figure 3 ] .
usual benign vertebral compression ( a ) multiple levels , diffuse radiolucency , and whole vertebral endplate involvement ( arrows ) ; usual malignant vertebral compression characteristics ( b ) single vertebral involvement , focal and bulging of the posterior wall ( arrowheads ) . missed fracture of the odontoid process and vertebral body of c2 ( arrows ) in a patient with a history of fall one month before .
transverse fracture of thoracic vertebral body ( arrow ) and posterior arch ( arrowhead ) with posterior epidural hematoma ( curved arrow ) in an ankylosed spine depicted on ( a ) t1- and ( b ) t2-weighted sequences .
other important sites of fractures are the hip and the pelvis , which are associated with increased mortality and specific diagnostic problems in the elderly population .
they are common and frequently result from lateral falls directly on the greater trochanter , in the case of hip fractures , and forward or backward falls in the case of pelvic fractures .
most fractures are easily diagnosed by conventional radiography , particularly fractures of the proximal femur .
however , non - displaced fractures may be negative or equivocal , particularly if the bone is osteoporotic .
if a clinical suspicion of a fracture persists , ct or better still mr imaging is advocated , as this modality can show the fracture line surrounded by bone marrow edema .
they may occur everywhere , but are particularly common in the hip and pelvis , the majority being located in the sacrum and pubic ramus [ figure 4 ] .
radiographic findings are often subtle or unremarkable , and in suspected cases mr imaging is indicated due to its superior accuracy as compared to other radiological methods .
all the images should be carefully analyzed , as multiple insufficiency fractures are frequent [ figure 5 ] .
subchondral fractures are particularly difficult to identify on radiographs , but the thin hypointense line that represents the fracture , surrounded by a variable degree of edema , is well demonstrated on an mri [ figure 6 ] . this kind of fracture can be complicated by a necrosis of the subchondral bone , which is hypointense on t2 weighted images , and is not enhanced following gadolinium administration .
insufficiency fractures ( arrows ) located in the sacrum with adjacent edema ( arrowheads ) , better depicted on ( a ) t1- and ( b ) t2- weighted sequences , respectively .
multiple fractures ( white arrows ) in ( a ) the proximal femur and ( b ) pubic ramus on coronal t1-weighted images subchondral fracture of the femoral head : ( a ) conventional radiography and ( b ) fat saturated sagittal t2-weighted image ( white arrow ) .
osteoarthritis ( oa ) can be defined as a group of distinct , but overlapping diseases , which may have different etiologies , but similar biological , morphological , and clinical outcomes  affecting the articular cartilage , subchondral bone , ligaments , joint capsule , synovial membrane , and periarticular muscles .
pathological changes can include fibrillation of cartilage , disruption of collagen fibers , changes in proteoglycan staining , chondrocyte proliferation , necrosis , and neovascularization .
oa is the most common joint disease in persons 65 years of age and above , with a radiographic prevalence as high as approximately 90% in women and 80% in men.[3335 ] its etiology is not fully understood , although there are several related factors , such as female gender , genetics , metabolism , and excessive mechanical stress .
it frequently leads to decreased function and loss of independence . although the joints of the hand are the most commonly affected , they are less likely to be symptomatic than the knee or hip [ figure 7 ] . the diagnosis of oa is primarily based on clinical history and physical examination .
plain radiographs can help confirm both the diagnosis and grade the severity of the condition .
the cardinal radiographic features of oa are focal / non - uniform narrowing of the joint space in the areas subjected to the most pressure , subchondral cysts , subchondral sclerosis , and osteophytes .
however , the severity of the spondylolisthesis of the radiographic changes does not correlate with the clinical symptoms .
shoulder oa and rotator cuff disease are also fairly common in the elderly and are associated with significant shoulder pain and disability related to decreased shoulder movement .
direct signs of oa and indirect signs of large rotator cuff tears can be seen on plain films , including superior humeral head migration and remodeling of the acromion and the greater tuberosity .
ultrasound is another valuable tool for easy assessment of the rotator cuff tendons due to its good sensitivity and specificity [ figure 8 ] .
however , when surgical treatment is considered , arthro - ct , or mri may be preferred , in order to improve its planning .
the lumbar and cervical spine is also frequently affected , with degenerative changes of the disk spaces , facet joints , and spinous processes , and sometimes with progressive scoliosis .
although the intervertebral disks are not synovial joints , the pathological changes are similar to those seen in the articular cartilage .
ct and mri are routinely used for the evaluation of narrowing of the central canal , lateral recesses , and neural foramina , when such an assessment is required ( percutaneous or surgical treatment ) . besides , mri can be useful in evaluating marrow changes in the vertebral plate , especially inflammatory changes ( type i modic ) , which present a positive correlation with low back pain . typical osteoarthritis of ( a ) the distal and proximal interphalangeal joints and ( b ) hip joint : joint space narrowing ( arrows ) , subchondral cysts ( arrowheads ) , osteophytes ( curved arrows ) , and subchondral sclerosis ( thick arrow ) .
ultrasound images in ( a ) the long and ( b ) short axis of the supraspinatus tendon demonstrating a complete tear ( arrowheads ) .
the frequency of microcrystal disorders also increases with age ; this is mainly true of gout and calcium pyrophosphate dihydrate deposition ( cpdd ) arthropathy .
gout is the most common inflammatory arthritis in the elderly and is characterized by a disturbance of purine metabolism , with deposits in the joints , cartilage , and kidneys .
the first metatarsophalangeal joint is the most common site of involvement in gouty arthritis [ figure 9 ] , but any joint can be involved .
the typical radiographic features include eccentric nodular soft tissue masses ( particularly suggestive of tophus when they are dense ) , close erosions ( also suggestive when located at a distance from the joint and when associated with an elevated bony margin ) , preservation of the joint space , exuberant bony proliferation , and lack of periarticular osteoporosis .
when the clinical , biological , and radiographic findings are uncertain , an ultrasound may be particularly helpful , as this technique may demonstrate more tophi [ figure 10 ] and erosions than plain films , more synovitis than a clinical examination , suggestive hyperechoic aggregates in the synovium or in the joint fluid , which may be aspirated , and the double contour sign ( an irregular hyperechoic band over the superficial margin of the articular cartilage , related to crystal deposition).[4244 ] calcium pyrophosphate dihydrate deposition ( cpdd ) disease is characterized by articular and periarticular tissue deposits ( hyaline cartilage , fibrocartilage , and other soft - tissue structures ) , even in the spine [ figure 11 ] . unlike gout , in which the increase in serum urates leads to supersaturation and deposits in the joints , in cpdd , the calcium deposits usually appear in the cartilage in the absence of any serum abnormality .
even though such deposits may be seen in asymptomatic patients , they may be associated with the development of severe arthropathies or with acute pain related to the migration of the crystals in the synovial fluid , mimicking septic arthritis .
gout of the first mtp joint in conventional radiography : excentric dense nodular soft tissue mass ( arrows ) , large erosions ( arrowhead ) , lack of periarticular osteoporosis , and exuberant bony proliferation ( curved arrow ) . gout involvement of the mtp ( a ) shows the tophus ( arrow ) with hyperechogenic microcrystal deposits ( arrowheads ) and a thickened synovium ( curved arrows ) . another patient with tophus deposition in the dorsal midfoot ( b ) demonstrates microcrystal deposits ( arrowhead ) with acoustic shadows ( thick arrows ) .
calcium pyrophosphate dihydrate deposition disease demonstrated by deposits of microcrystals in the menisci ( arrow ) , articular cartilage ( arrowhead ) , and periarticular soft tissue ( curved arrow ) .
elderly patients are more prone to infection because of an increased incidence of predisposing disorders ( diabetes mellitus , peripheral vascular disease , poor dentition ,  ) , immunosuppression and surgical procedures in this population ( dental extractions , open heart surgery , prosthetic joint replacement ,  ) .
the infectious agents affecting elderly patients are similar to those found in the younger population ; although in the elderly , evidence shows an increased incidence of infection by nosocomial organisms ( due to institutionalization and hospitalization ) .
these infections can have a relatively benign course , as in the case of cellulitis , or serious consequences , as with necrotizing fasciitis .
in patients over 80 years of age , the knee , shoulder , and hip are the most frequently affected joints .
another peculiarity of the elderly , uncommon in adults , is acute hematogenous osteomyelitis that mainly affects the spine .
attention should , moreover , be paid to the diagnosis of tuberculosis , as early manifestations are subtle and advanced disease mimics other infections , granulomatous diseases , and malignancy .
tuberculosis may affect the spine ( about 50% of cases ) , with potential neurological consequences , or any joint , causing deformity [ figure 12 ] .
it should be noted that elderly men may present with bone lesions , as a manifestation of reactivation of the disease . as there are no pathognomonic imaging signs of musculoskeletal tuberculosis ,
the most conclusive means of reaching a diagnosis is by biopsy and culture , as chest radiographs and skin tests may not be positive in the elderly . as regards imaging techniques , magnetic resonance imaging is the modality of choice for musculoskeletal infection , as it best delineates the extension of soft tissue infections .
computed tomography , ultrasound , radiography , and nuclear medicine studies are considered to be ancillary . in some circumstances ultrasound
can be very useful , as it allows the aspiration of fluid collected in the joints or soft tissue , the evaluation of structures adjacent to orthopedic hardware , or the assessment of small peripheral joints . besides , in the case of debilitated elderly patients , a mobile ultrasound device can be easily moved close to their beds .
( a ) on conventional radiography there is mild osteoporosis , extensive soft tissue swelling , and large marginal erosion ( arrowhead ) , ( b ) on doppler ultrasound the synovitis ( arrows ) and bone erosion ( arrowhead ) are well - depicted .
paget 's disease is a bone disorder characterized by an increase in osteoclast - mediated bone resorption accompanied by osteoblast - mediated formation of new bone of inferior quality .
the frequency of this condition is decreasing , but it still exists in 1  5% of persons over 50 years of age , varying according to geographic areas.[5356 ] the radiographic signs include an advancing wedge of bone resorption , an accentuation and coarsening of the bone trabeculae along lines of stress , cortical thickening , and enlargement of the bone [ figure 13 ] . as a result , secondary osteoarthritis , insufficiency fractures , bowing of the bones , and even spinal cord or nerve root compression can be observed . in a minority of cases ,
sarcomatous degeneration may develop , mainly in the humerus , pelvis , and proximal femur , with a frequency believed to range from 0.9 to 2% .
paget 's disease affecting the iliac bone demonstrated with coarsening of the bone trabeculae and cortical thickening ( arrows ) .
tumors : tumors can be revealed by bone pain , pathological fractures , or disability , or be discovered as an incidental finding .
primary bone tumors in elderly patients are not common , but , due to the risk of metastases , any newly discovered bone lesion or one developing within a known pre - existing lesion must be assumed to be malignant until proven otherwise .
metastases : bone metastases are a common complication of malignant disease , especially of the breast , prostate , and lung .
although they are often multiple , a solitary metastasis is still more common than a primary neoplasm .
plain films are relatively insensitive for the detection of bone metastases , especially subtle lesions .
mr imaging is superior to ct in the detection of malignant marrow infiltration , and it has a better contrast resolution for visualizing soft tissue and spinal cord lesions . even with the advances in mri , especially for bone marrow screening , bone scintigraphy continues to be used as an effective method for initial evaluation of the whole body for bone metastases .
sarcomas : in the elderly population , many sarcomas are secondary to a pre - existing disorder of the bone , such as paget 's disease , or lesions treated by radiation .
chondrosarcoma must also be kept in mind , especially when isolated osteolytic lesions of the pelvis are seen , as this is the most common primary sarcoma of bone in adults .
the cartilaginous nature of the lesion may be suggested by the presence of calcifications or by a lobulated hyperintense lesion in an mri [ figure 14 ] .
chondrosarcoma of the pelvis in ( a ) conventional radiography appears as an isolated osteolytic lesion ( arrows ) , ( b ) coronal t2-weighted image demonstrates a lobulated hyperintense lesion ( arrowheads ) .
myeloma : myeloma is a characteristic disease in the elderly population , with a peak incidence in the eighth decade that results from an unregulated , progressive proliferation of neoplastic monoclonal plasma cells that accumulate in the bone marrow , leading to anemia and marrow failure .
osteolytic lesions may be present on plain films , but differentiating osteoporotic vertebral compression fractures from those associated with myeloma is a common diagnostic dilemma , as bone loss may be the first sign revealing the latter disease .
indeed , widespread osteoporosis , due to cytokine - mediated osteoclast activation , is common in patients with myeloma .
this possible association must be kept in mind , particularly if other features are present , including unexplained back or bone pain .
we used the following terms and some of its combinations : elderly , aged , epidemiology , fracture , osteoporosis , vertebral , hip , pelvis , arthritis , neoplasm , malignancy , myeloma , paget , gout , infection , microcrystal , and radiology .
articles without english abstracts were excluded . besides , certain relevant rheumatological , orthopedic , and radiological books were also used .
fractures are frequent in the elderly and result mainly from the effects of falls and osteoporosis .
low - impact falls , even from standing height , are the most common cause of injury in geriatric patients . falling is a multi - factorial problem due to both extrinsic ( e.g. , environmental and housing conditions ) and intrinsic risk factors ( e.g. , impaired mobility , loss of muscular strength , poor visual acuity , and medication , for instance corticoids).[46 ] osteoporosis , which is characterized by qualitatively normal , but quantitatively deficient bone , leads to bone fragility and increased risk of fractures .
the general prevalence of osteoporosis in women is approximately 50% at the age of 85 years , while in men the prevalence is about 20% at that age .
ethnic differences also exist : mineral bone density is higher in black women and lower in asian women , while in white women evidence shows an intermediate value . due to its precision
, the most widely used quantitative technique is dual energy x - ray absorptiometry , which makes it possible to diagnose osteoporosis early , predict the risk of fracture , determine therapeutic intervention , and monitor response to treatment . this method grades bone loss according to standard deviations ( sd ) from the mean young adult value .
a value less than 2.5 times the sd below the young adult mean , is considered to indicate osteoporosis .
the main radiographic features of osteoporosis are increased radiolucency and cortical thinning , mainly in the spine , giving rise to a well - demarcated outline of the vertebral body , which has been described as , 
picture framing. besides , in the spine , an increased biconcavity of the vertebral end plates , with a protrusion of the intervertebral disk into the vertebral body can be observed .
however , early radiographic changes are subtle , as a bone loss of approximately 30% must occur before it can be detected .
vertebral compression fractures are the most common osteoporotic fractures , with a greater incidence in women over 60 years of age .
they can be observed in up to 25% of women over 70 years of age and 40% of those over 80 years .
after one episode , the risk of subsequent vertebral fracture increases at least four - fold , with substantially increased rates during the first year .
these fractures are associated with higher mortality and significant morbidity , even though they are afforded little clinical attention .
they often appear as multiple fractures with anterior wedging , and may be associated with significant deformity , leading to kyphosis .
they are usually well demonstrated on radiographs , but can be better assessed with computed tomography ( ct ) or magnetic resonance ( mr ) imaging , when necessary .
the latter imaging modality may be indicated in case of associated neurological symptoms  a rare event  or when a vertebroplasty is discussed , in order to better localize the recently fractured vertebra .
vertebral compression fractures in the elderly may involve several problems : first is differentiating between osteoporotic and malignant vertebral collapse ( vc ) , particularly metastatic vc , as the latter is by far the most common malignant tumor affecting the skeleton in the elderly . in most patients ,
multiple , relatively symmetrical thoracolumbar vcs , associated with diffuse increased radiolucency are suggestive of osteoporosis [ figure 1a ] .
the whole vertebral endplate is impacted , sometimes in association with increased or decreased radiolucency of the subjacent trabecular bone ( band - like distribution of the abnormalities under the fractured vertebral end plate ) .
gas can also be seen under the fracture and is nearly pathognomonic of the benign nature of the collapse .
there is no cortical osteolysis , although fractures can be identified with retropulsion of a bone fragment .
conversely , the following are a cause for concern : a single vc , involvement of the cervical spine , heterogeneous increased or decreased radiolucency that can not be explained by an underlying end plate fracture , a focal collapse ( on the ap or lateral view ) , or a bulging of the vertebral body or cortical osteolysis [ figure 1b ] . if in doubt or for a better assessment of the spinal canal and soft tissue , ct , or better yet , an mri can be performed , in order to differentiate between these two disorders . in benign fractures , an mri may show a band distribution of abnormal signal intensities on t1 and t2 weighted images , spared normal bone marrow signal intensity , retropulsion of a posterior bone fragment , and multiple compression fractures ; on the contrary , signs such as a convex posterior border of the vertebral body , abnormal signal intensity of the posterior elements , an epidural mass or a focal paraspinal mass are suggestive of spinal metastasis.[1921 ] second , vertebral fractures can be missed following moderate trauma , because the fracture may be difficult to identify in an osteoporotic radiolucent bone and / or because the pain is attributed to another painful condition , such as degenerative changes .
this is observed in particular in the cervical spine , particularly at c2 , and may lead to secondary neurological complications [ figure 2 ] .
ankylosis may be related to ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis , which especially affect males and they have an estimated frequency of 5 to 15% in the elderly.[2225 ] these ankylosed spines become increasingly susceptible to injury , even in the event of low - energy impacts , and are prone to unstable vertebral fractures with an increased frequency of neurological complications , either primary or secondary , after unprotected transfers and manipulation .
these lesions may be missed on plain films when non - displaced or mildly displaced , especially in hyperextension , whereas , they are well demonstrated on ct or mr imaging .
however , the mri features can sometimes be misleading and mimic infectious spondylitis when signal abnormalities of the disco - vertebral junction are present .
caution is required when an elderly patient presents with an ankylosed spine , minor trauma or acute pain , especially if signal abnormalities of the anterior and posterior spine are observed [ figure 3 ] .
usual benign vertebral compression ( a ) multiple levels , diffuse radiolucency , and whole vertebral endplate involvement ( arrows ) ; usual malignant vertebral compression characteristics ( b ) single vertebral involvement , focal and bulging of the posterior wall ( arrowheads ) . missed fracture of the odontoid process and vertebral body of c2 ( arrows ) in a patient with a history of fall one month before .
transverse fracture of thoracic vertebral body ( arrow ) and posterior arch ( arrowhead ) with posterior epidural hematoma ( curved arrow ) in an ankylosed spine depicted on ( a ) t1- and ( b ) t2-weighted sequences .
other important sites of fractures are the hip and the pelvis , which are associated with increased mortality and specific diagnostic problems in the elderly population .
they are common and frequently result from lateral falls directly on the greater trochanter , in the case of hip fractures , and forward or backward falls in the case of pelvic fractures .
most fractures are easily diagnosed by conventional radiography , particularly fractures of the proximal femur . however , non - displaced fractures may be negative or equivocal , particularly if the bone is osteoporotic .
if a clinical suspicion of a fracture persists , ct or better still mr imaging is advocated , as this modality can show the fracture line surrounded by bone marrow edema .
they may occur everywhere , but are particularly common in the hip and pelvis , the majority being located in the sacrum and pubic ramus [ figure 4 ] .
radiographic findings are often subtle or unremarkable , and in suspected cases mr imaging is indicated due to its superior accuracy as compared to other radiological methods .
all the images should be carefully analyzed , as multiple insufficiency fractures are frequent [ figure 5 ] .
subchondral fractures are particularly difficult to identify on radiographs , but the thin hypointense line that represents the fracture , surrounded by a variable degree of edema , is well demonstrated on an mri [ figure 6 ] . this kind of fracture can be complicated by a necrosis of the subchondral bone , which is hypointense on t2 weighted images , and is not enhanced following gadolinium administration .
insufficiency fractures ( arrows ) located in the sacrum with adjacent edema ( arrowheads ) , better depicted on ( a ) t1- and ( b ) t2- weighted sequences , respectively .
multiple fractures ( white arrows ) in ( a ) the proximal femur and ( b ) pubic ramus on coronal t1-weighted images subchondral fracture of the femoral head : ( a ) conventional radiography and ( b ) fat saturated sagittal t2-weighted image ( white arrow ) .
osteoarthritis ( oa ) can be defined as a group of distinct , but overlapping diseases , which may have different etiologies , but similar biological , morphological , and clinical outcomes  affecting the articular cartilage , subchondral bone , ligaments , joint capsule , synovial membrane , and periarticular muscles .
pathological changes can include fibrillation of cartilage , disruption of collagen fibers , changes in proteoglycan staining , chondrocyte proliferation , necrosis , and neovascularization .
oa is the most common joint disease in persons 65 years of age and above , with a radiographic prevalence as high as approximately 90% in women and 80% in men.[3335 ] its etiology is not fully understood , although there are several related factors , such as female gender , genetics , metabolism , and excessive mechanical stress .
although the joints of the hand are the most commonly affected , they are less likely to be symptomatic than the knee or hip [ figure 7 ] . the diagnosis of oa is primarily based on clinical history and physical examination .
plain radiographs can help confirm both the diagnosis and grade the severity of the condition .
the cardinal radiographic features of oa are focal / non - uniform narrowing of the joint space in the areas subjected to the most pressure , subchondral cysts , subchondral sclerosis , and osteophytes .
however , the severity of the spondylolisthesis of the radiographic changes does not correlate with the clinical symptoms .
shoulder oa and rotator cuff disease are also fairly common in the elderly and are associated with significant shoulder pain and disability related to decreased shoulder movement .
direct signs of oa and indirect signs of large rotator cuff tears can be seen on plain films , including superior humeral head migration and remodeling of the acromion and the greater tuberosity .
ultrasound is another valuable tool for easy assessment of the rotator cuff tendons due to its good sensitivity and specificity [ figure 8 ] .
however , when surgical treatment is considered , arthro - ct , or mri may be preferred , in order to improve its planning .
the lumbar and cervical spine is also frequently affected , with degenerative changes of the disk spaces , facet joints , and spinous processes , and sometimes with progressive scoliosis . although the intervertebral disks are not synovial joints , the pathological changes are similar to those seen in the articular cartilage .
ct and mri are routinely used for the evaluation of narrowing of the central canal , lateral recesses , and neural foramina , when such an assessment is required ( percutaneous or surgical treatment ) . besides , mri can be useful in evaluating marrow changes in the vertebral plate , especially inflammatory changes ( type i modic ) , which present a positive correlation with low back pain . typical osteoarthritis of ( a ) the distal and proximal interphalangeal joints and ( b ) hip joint : joint space narrowing ( arrows ) , subchondral cysts ( arrowheads ) , osteophytes ( curved arrows ) , and subchondral sclerosis ( thick arrow ) .
ultrasound images in ( a ) the long and ( b ) short axis of the supraspinatus tendon demonstrating a complete tear ( arrowheads ) .
the frequency of microcrystal disorders also increases with age ; this is mainly true of gout and calcium pyrophosphate dihydrate deposition ( cpdd ) arthropathy .
gout is the most common inflammatory arthritis in the elderly and is characterized by a disturbance of purine metabolism , with deposits in the joints , cartilage , and kidneys .
the first metatarsophalangeal joint is the most common site of involvement in gouty arthritis [ figure 9 ] , but any joint can be involved .
the typical radiographic features include eccentric nodular soft tissue masses ( particularly suggestive of tophus when they are dense ) , close erosions ( also suggestive when located at a distance from the joint and when associated with an elevated bony margin ) , preservation of the joint space , exuberant bony proliferation , and lack of periarticular osteoporosis .
when the clinical , biological , and radiographic findings are uncertain , an ultrasound may be particularly helpful , as this technique may demonstrate more tophi [ figure 10 ] and erosions than plain films , more synovitis than a clinical examination , suggestive hyperechoic aggregates in the synovium or in the joint fluid , which may be aspirated , and the double contour sign ( an irregular hyperechoic band over the superficial margin of the articular cartilage , related to crystal deposition).[4244 ] calcium pyrophosphate dihydrate deposition ( cpdd ) disease is characterized by articular and periarticular tissue deposits ( hyaline cartilage , fibrocartilage , and other soft - tissue structures ) , even in the spine [ figure 11 ] . unlike gout ,
in which the increase in serum urates leads to supersaturation and deposits in the joints , in cpdd , the calcium deposits usually appear in the cartilage in the absence of any serum abnormality .
even though such deposits may be seen in asymptomatic patients , they may be associated with the development of severe arthropathies or with acute pain related to the migration of the crystals in the synovial fluid , mimicking septic arthritis .
gout of the first mtp joint in conventional radiography : excentric dense nodular soft tissue mass ( arrows ) , large erosions ( arrowhead ) , lack of periarticular osteoporosis , and exuberant bony proliferation ( curved arrow ) . gout involvement of the mtp ( a ) shows the tophus ( arrow ) with hyperechogenic microcrystal deposits ( arrowheads ) and a thickened synovium ( curved arrows ) . another patient with tophus deposition in the dorsal midfoot ( b ) demonstrates microcrystal deposits ( arrowhead ) with acoustic shadows ( thick arrows ) .
calcium pyrophosphate dihydrate deposition disease demonstrated by deposits of microcrystals in the menisci ( arrow ) , articular cartilage ( arrowhead ) , and periarticular soft tissue ( curved arrow ) .
elderly patients are more prone to infection because of an increased incidence of predisposing disorders ( diabetes mellitus , peripheral vascular disease , poor dentition ,  ) , immunosuppression and surgical procedures in this population ( dental extractions , open heart surgery , prosthetic joint replacement ,  ) .
the infectious agents affecting elderly patients are similar to those found in the younger population ; although in the elderly , evidence shows an increased incidence of infection by nosocomial organisms ( due to institutionalization and hospitalization ) .
these infections can have a relatively benign course , as in the case of cellulitis , or serious consequences , as with necrotizing fasciitis . in patients over 80 years of age ,
another peculiarity of the elderly , uncommon in adults , is acute hematogenous osteomyelitis that mainly affects the spine .
attention should , moreover , be paid to the diagnosis of tuberculosis , as early manifestations are subtle and advanced disease mimics other infections , granulomatous diseases , and malignancy .
tuberculosis may affect the spine ( about 50% of cases ) , with potential neurological consequences , or any joint , causing deformity [ figure 12 ] .
it should be noted that elderly men may present with bone lesions , as a manifestation of reactivation of the disease . as there are no pathognomonic imaging signs of musculoskeletal tuberculosis ,
the most conclusive means of reaching a diagnosis is by biopsy and culture , as chest radiographs and skin tests may not be positive in the elderly . as regards imaging techniques ,
magnetic resonance imaging is the modality of choice for musculoskeletal infection , as it best delineates the extension of soft tissue infections .
computed tomography , ultrasound , radiography , and nuclear medicine studies are considered to be ancillary . in some circumstances ultrasound
can be very useful , as it allows the aspiration of fluid collected in the joints or soft tissue , the evaluation of structures adjacent to orthopedic hardware , or the assessment of small peripheral joints . besides , in the case of debilitated elderly patients , a mobile ultrasound device can be easily moved close to their beds .
( a ) on conventional radiography there is mild osteoporosis , extensive soft tissue swelling , and large marginal erosion ( arrowhead ) , ( b ) on doppler ultrasound the synovitis ( arrows ) and bone erosion ( arrowhead ) are well - depicted .
paget 's disease is a bone disorder characterized by an increase in osteoclast - mediated bone resorption accompanied by osteoblast - mediated formation of new bone of inferior quality .
the frequency of this condition is decreasing , but it still exists in 1  5% of persons over 50 years of age , varying according to geographic areas.[5356 ] the radiographic signs include an advancing wedge of bone resorption , an accentuation and coarsening of the bone trabeculae along lines of stress , cortical thickening , and enlargement of the bone [ figure 13 ] . as a result , secondary osteoarthritis , insufficiency fractures , bowing of the bones , and even spinal cord or nerve root compression can be observed . in a minority of cases ,
sarcomatous degeneration may develop , mainly in the humerus , pelvis , and proximal femur , with a frequency believed to range from 0.9 to 2% .
paget 's disease affecting the iliac bone demonstrated with coarsening of the bone trabeculae and cortical thickening ( arrows ) .
tumors : tumors can be revealed by bone pain , pathological fractures , or disability , or be discovered as an incidental finding .
primary bone tumors in elderly patients are not common , but , due to the risk of metastases , any newly discovered bone lesion or one developing within a known pre - existing lesion must be assumed to be malignant until proven otherwise .
metastases : bone metastases are a common complication of malignant disease , especially of the breast , prostate , and lung .
although they are often multiple , a solitary metastasis is still more common than a primary neoplasm .
plain films are relatively insensitive for the detection of bone metastases , especially subtle lesions . mr imaging is superior to ct in the detection of malignant marrow infiltration , and it has a better contrast resolution for visualizing soft tissue and spinal cord lesions .
even with the advances in mri , especially for bone marrow screening , bone scintigraphy continues to be used as an effective method for initial evaluation of the whole body for bone metastases .
sarcomas : in the elderly population , many sarcomas are secondary to a pre - existing disorder of the bone , such as paget 's disease , or lesions treated by radiation .
chondrosarcoma must also be kept in mind , especially when isolated osteolytic lesions of the pelvis are seen , as this is the most common primary sarcoma of bone in adults .
the cartilaginous nature of the lesion may be suggested by the presence of calcifications or by a lobulated hyperintense lesion in an mri [ figure 14 ] .
chondrosarcoma of the pelvis in ( a ) conventional radiography appears as an isolated osteolytic lesion ( arrows ) , ( b ) coronal t2-weighted image demonstrates a lobulated hyperintense lesion ( arrowheads ) .
myeloma : myeloma is a characteristic disease in the elderly population , with a peak incidence in the eighth decade that results from an unregulated , progressive proliferation of neoplastic monoclonal plasma cells that accumulate in the bone marrow , leading to anemia and marrow failure .
osteolytic lesions may be present on plain films , but differentiating osteoporotic vertebral compression fractures from those associated with myeloma is a common diagnostic dilemma , as bone loss may be the first sign revealing the latter disease .
indeed , widespread osteoporosis , due to cytokine - mediated osteoclast activation , is common in patients with myeloma .
this possible association must be kept in mind , particularly if other features are present , including unexplained back or bone pain .
special attention is required in this population , as an early diagnosis can avoid delay in treatment , which is associated with increased morbidity and mortality . besides , a better understanding of musculoskeletal diseases can lead to the implementation of effective preventive measures , thus reducing public health expenditure , and improving the quality of life in the elderly .
 musculoskeletal disorders are among the most common problems affecting the elderly . 
 the resulting loss of mobility and physical independence can be particularly devastating in this population . 
 the aim of this article is to present some of the most frequent musculoskeletal disorders of the elderly , such as fractures , osteoporosis , osteoarthritis , microcrystal disorders , infections , and tumors . 
INTRODUCTION
Search criteria
Fractures
Osteoarthritis and associated conditions
Microcrystal disorders
Infection
Paget's disease
CONCLUSION