Atypical infections:
Brodie's abscess
CRMO
Tuberculosis:
Soft tisuue
Other infections:
Fungal osteomyelitis
TB: soft tissue
Involves tenosynovium, bursa, muscle or deep fascia
Usually associated with immunosuppressed
Reported in wrist, elbow, peroneal and achillis tendons
Often misdiagnosed initially, hence high radiological suspecion is important in the management
Many be due to extension from adjacent joint, bone, bursae, direct inoculation (trauma, syringe)
References:
Varshney MK et al. Isolated tuberculosis of achillis tendon. Joint bone spine: 74: 103-106
Usually associated with immunosuppressed
Reported in wrist, elbow, peroneal and achillis tendons
Often misdiagnosed initially, hence high radiological suspecion is important in the management
Many be due to extension from adjacent joint, bone, bursae, direct inoculation (trauma, syringe)
References:
Varshney MK et al. Isolated tuberculosis of achillis tendon. Joint bone spine: 74: 103-106
Journal Watch: Patellar tendon
Ultrasound is more accurate than MRI in patellar tendinopathy:
The American Journal of Sports Medicine 35:427-436
Warden SJ et al compared the accuracy of MRI and ultrasound the diagnosis of patellar tendopathy in a cohort study comprising 30 patients with clinically diagnosed patellar tendinoapthy and 33 matched controls. They found ultrasound was more accurate than MRI in confirming clinically diagnosed patellar tendinopathy.
The American Journal of Sports Medicine 35:427-436
Warden SJ et al compared the accuracy of MRI and ultrasound the diagnosis of patellar tendopathy in a cohort study comprising 30 patients with clinically diagnosed patellar tendinoapthy and 33 matched controls. They found ultrasound was more accurate than MRI in confirming clinically diagnosed patellar tendinopathy.
Journal watch: Achillis tendon
Eccentric loading and low-energy shock-wave therapy in the management of Achillis tendinopathy:
The American Journal of Sports Medicine 35:374-383
Rompe JD et al from Germany performed a randomised control trail in 75 patients to compare the effectiveness of treatment in the chronic non-insertional achillis tendinopathy with eccentric loading, repetitive low-energy shock-wave therapy and wait-and-see. At 4-month follow-up, they concluded, the eccentric loading and low-energy shock-wave therapy showed comparable results, while the wait-and-see strategy was ineffective.
The American Journal of Sports Medicine 35:374-383
Rompe JD et al from Germany performed a randomised control trail in 75 patients to compare the effectiveness of treatment in the chronic non-insertional achillis tendinopathy with eccentric loading, repetitive low-energy shock-wave therapy and wait-and-see. At 4-month follow-up, they concluded, the eccentric loading and low-energy shock-wave therapy showed comparable results, while the wait-and-see strategy was ineffective.
Reverse total shoulder replacement
Indications:
Completely torn rotator cuffs with severe arthritis
Previous failed shoulder replacement
Advantages:
Metal ball is attached to glenoid and a plastic socket to humerus, which allows to use deltoid instead of the torn rotator cuff.
Complications:
Dislocation of the components
Notching of the scapula
Acromial stress fractures
Completely torn rotator cuffs with severe arthritis
Previous failed shoulder replacement
Advantages:
Metal ball is attached to glenoid and a plastic socket to humerus, which allows to use deltoid instead of the torn rotator cuff.
Complications:
Dislocation of the components
Notching of the scapula
Acromial stress fractures
Meniscal cysts
Most commonly associated with horizontal tears
Seen in 1% meniscectomies
Intrameniscal cyst
Uncommon, represent intrameniscal fluid collection
Associated with tear
Seen at the level of the joint line
Secondary to trauma, degeneration or meniscectomy
Low on T1 and high on T2, T2* and STIR
Blood and gelatin may change signal
May be loculated or septated
Lateral:
5 times more common than medial ones
90% are associated with horizontal tears
Commonly seen anterior to LCL or between LCL and popliteus
Medial:
Tend to be larger than lateral
May dissect joint capsule or MCL
Commonly deep to MCL or posteromedial corner deep to posterior oblique ligament
Differentials:
Osteophyte spurring, synovial cyst, tibiofibular cyst, busristis, masses
Parameniscal cyst
Most common
Seen at the periphery of the meniscus
Synovial cyst
Rare
Not associated with meniscal tear
Represent cystic outpouching of the joint capsule
Seen in 1% meniscectomies
Intrameniscal cyst
Uncommon, represent intrameniscal fluid collection
Associated with tear
Seen at the level of the joint line
Secondary to trauma, degeneration or meniscectomy
Low on T1 and high on T2, T2* and STIR
Blood and gelatin may change signal
May be loculated or septated
Lateral:
5 times more common than medial ones
90% are associated with horizontal tears
Commonly seen anterior to LCL or between LCL and popliteus
Medial:
Tend to be larger than lateral
May dissect joint capsule or MCL
Commonly deep to MCL or posteromedial corner deep to posterior oblique ligament
Differentials:
Osteophyte spurring, synovial cyst, tibiofibular cyst, busristis, masses
Parameniscal cyst
Most common
Seen at the periphery of the meniscus
Synovial cyst
Rare
Not associated with meniscal tear
Represent cystic outpouching of the joint capsule
Pitfalls in diagnosis of meniscal pathologies
Transverse ligament:
Can simulate grade 3 oblique tears, in up to 30% of MR examinations, adjacent to anterior horn of LM on sagittal images and is created by fat between anterior horn and transverse ligament.
Infrequently, can mimic MM tearRemember isolated anterior horn tears are uncommon
Central rhombdoid attachment of anterior horn of the lateral meniscus:
May itself show increased signal.
On sagittal directed obliquely upwards and may be seen on more than 1 image adjacent to intercondylar notch
Branch from lateral inferior geniculate artery:
May mimic tear adjacent to anterior horn of LM
Meniscofemoral ligament:
Meniscal insertion may micmic vertical tear in the posterior horn of LM due to fat between LM and MFL
Popliteus tendon sheath:
Mimics grade 3 tear in the posterior horn of LM
Intermediate on T1 and T2Runs oblique from front to back in superior to inferior direction
Usually tears are oriented opposite to that of popliteus tendon, but vertical tear may be parallel.
Pseudo bucket-handle tear:
In coronal MRI, when knee in external rotation, body and posterior horn of LM seen in same section mimics bicket handle tear
Correlation with sagittal images is needed
Lax meniscal sign (buckled meniscus):
Commonly seen in MM. Often secondary to fractures and joint laxity. May simulate tear
Vacuum phenomenon:
Produces blooming artefact on GRE
Pseuo loose body:
Intercondylar notch signal on T2* or fat-sat images. T1 will solve the dilemmaMCL bursa:Seen between MM and MCL and bursa may be mistaken for tear
Fibrillation:
High signal restricted to the apex without foreshortening or abnormal morphology
Diffuse meniscal edema:
Rarely seen similar to fibrillation, but more prominent
Magic angle effect:
Seen in medial segment of posterior horn of LM
Partial volume averaging:
Seen in the periphery
More common in MM 30%, LM 6%
Can simulate grade 3 oblique tears, in up to 30% of MR examinations, adjacent to anterior horn of LM on sagittal images and is created by fat between anterior horn and transverse ligament.
Infrequently, can mimic MM tearRemember isolated anterior horn tears are uncommon
Central rhombdoid attachment of anterior horn of the lateral meniscus:
May itself show increased signal.
On sagittal directed obliquely upwards and may be seen on more than 1 image adjacent to intercondylar notch
Branch from lateral inferior geniculate artery:
May mimic tear adjacent to anterior horn of LM
Meniscofemoral ligament:
Meniscal insertion may micmic vertical tear in the posterior horn of LM due to fat between LM and MFL
Popliteus tendon sheath:
Mimics grade 3 tear in the posterior horn of LM
Intermediate on T1 and T2Runs oblique from front to back in superior to inferior direction
Usually tears are oriented opposite to that of popliteus tendon, but vertical tear may be parallel.
Pseudo bucket-handle tear:
In coronal MRI, when knee in external rotation, body and posterior horn of LM seen in same section mimics bicket handle tear
Correlation with sagittal images is needed
Lax meniscal sign (buckled meniscus):
Commonly seen in MM. Often secondary to fractures and joint laxity. May simulate tear
Vacuum phenomenon:
Produces blooming artefact on GRE
Pseuo loose body:
Intercondylar notch signal on T2* or fat-sat images. T1 will solve the dilemmaMCL bursa:Seen between MM and MCL and bursa may be mistaken for tear
Fibrillation:
High signal restricted to the apex without foreshortening or abnormal morphology
Diffuse meniscal edema:
Rarely seen similar to fibrillation, but more prominent
Magic angle effect:
Seen in medial segment of posterior horn of LM
Partial volume averaging:
Seen in the periphery
More common in MM 30%, LM 6%
Bucket handle tear
Clinical features:
Common in young secondary to trauma
Present with locked knee or inability to extend fully
General features:
Usually displaced longitudinal vertical tear, but may be seen in longitudinal horizontal tear
MM 3 times more common than LL
Central fragment may be displaced into intercondylar notch
Associated injuries:
ACL injuries common
IMAGING FINDINGS:
Absent bow-tie sign:
May be only sign. Normally bow-tie should be seen in 2 sections on sagittal.
Foreshortened or truncated or displaced anterior horn/posterior horn/ both leads to absent normal bow-tie configuration
False positive occur in children, degenerate meniscus, radial tear, post-op
False negative occurs in discoid meniscus
Smaller posterior horn:
Normally the posterior horn of MM is wider with more height than anterior horn. If that is lost, suspect BH tear
Disproportionate posterior horn sign:
Large posterior horn on sagittal images closer to the root than periphery due to central displacement
Decreased width of the meniscus:
Due to displacement. May or may not show increased signal! In fact, the displaced fragment is of low signal band
Pseudohypertrophy of anterior horn:
If the posterior horn is displaced anteriorly, causes pseudohypertrophy of anterior horn, commonly seen in LM
Seen on Sagittal
Displacement of anterior horn anteriorly:
Displacement of anterior horn anteriorly may be seen
Best seen on sagittal and axials
Flipped meniscal sign:
Fragment is flipped anteriorly adjacent to the ipsilateral anterior horn
Anterior horn should not measure more than 6 mm normally, of so, suspect BH tear with anterior flip
Double anterior horn sign:
Similar to above, but mimicks 2 anterior horns
Double PCL sign (displacement of posterior horn posteriorly):
Displacement of posterior horn posteriorly (double PCL sign or pseudo-PCL sign: low signal displaced posterior horn parallel and anterior to the PCL)
Best seen on sagittals
Displaced fragment seen in intercondylar notch:
Low signal fragment best seen on coronal
Fragment in notch sign:
Fragment of meniscus is in intercondylar notch, not in same sagittal plane as PCL; often seen in LM tear
Truncated meniscus on coronal images:
Happens in 65% bucket handle tears
Quadruple cruciate sign:
Bilateral BH tear
References:
Stoller DW. MRI in orthopaedics & sports medicine; Second edition; 1997. Chapter 7: the knee. Lippincott Williams & Wilkins.
Common in young secondary to trauma
Present with locked knee or inability to extend fully
General features:
Usually displaced longitudinal vertical tear, but may be seen in longitudinal horizontal tear
MM 3 times more common than LL
Central fragment may be displaced into intercondylar notch
Associated injuries:
ACL injuries common
IMAGING FINDINGS:
Absent bow-tie sign:
May be only sign. Normally bow-tie should be seen in 2 sections on sagittal.
Foreshortened or truncated or displaced anterior horn/posterior horn/ both leads to absent normal bow-tie configuration
False positive occur in children, degenerate meniscus, radial tear, post-op
False negative occurs in discoid meniscus
Smaller posterior horn:
Normally the posterior horn of MM is wider with more height than anterior horn. If that is lost, suspect BH tear
Disproportionate posterior horn sign:
Large posterior horn on sagittal images closer to the root than periphery due to central displacement
Decreased width of the meniscus:
Due to displacement. May or may not show increased signal! In fact, the displaced fragment is of low signal band
Pseudohypertrophy of anterior horn:
If the posterior horn is displaced anteriorly, causes pseudohypertrophy of anterior horn, commonly seen in LM
Seen on Sagittal
Displacement of anterior horn anteriorly:
Displacement of anterior horn anteriorly may be seen
Best seen on sagittal and axials
Flipped meniscal sign:
Fragment is flipped anteriorly adjacent to the ipsilateral anterior horn
Anterior horn should not measure more than 6 mm normally, of so, suspect BH tear with anterior flip
Double anterior horn sign:
Similar to above, but mimicks 2 anterior horns
Double PCL sign (displacement of posterior horn posteriorly):
Displacement of posterior horn posteriorly (double PCL sign or pseudo-PCL sign: low signal displaced posterior horn parallel and anterior to the PCL)
Best seen on sagittals
Displaced fragment seen in intercondylar notch:
Low signal fragment best seen on coronal
Fragment in notch sign:
Fragment of meniscus is in intercondylar notch, not in same sagittal plane as PCL; often seen in LM tear
Truncated meniscus on coronal images:
Happens in 65% bucket handle tears
Quadruple cruciate sign:
Bilateral BH tear
References:
Stoller DW. MRI in orthopaedics & sports medicine; Second edition; 1997. Chapter 7: the knee. Lippincott Williams & Wilkins.
MSK interventions: osteoid osteoma
Radiofrequency ablation:
Done under CT guidance
11 G radiofrequency-compatible coaxial needle
2 mm coaxial drill system
1.0 cm active tip 17 G non-cooled radiofrequency needle
At 90 °C for 6 min.
Absolute alcohol injection:
Usually after RFA
0.5–1.0 ml absolute alcohol into the nidus using 20 G needle
Prognosis:
Technical success rate 100%
Pain relief in 96%
Complications:
Rare
Local cellulitis
Paresthesia
Reference:
Akhlaghpoor S et al. Percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation. Clin Rad (2007). 62: 268-273
Done under CT guidance
11 G radiofrequency-compatible coaxial needle
2 mm coaxial drill system
1.0 cm active tip 17 G non-cooled radiofrequency needle
At 90 °C for 6 min.
Absolute alcohol injection:
Usually after RFA
0.5–1.0 ml absolute alcohol into the nidus using 20 G needle
Prognosis:
Technical success rate 100%
Pain relief in 96%
Complications:
Rare
Local cellulitis
Paresthesia
Reference:
Akhlaghpoor S et al. Percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation. Clin Rad (2007). 62: 268-273
Journal watch: Osteoid osteoma
Percutaneous combination therapy of radiofrequency and alcohol ablation in osteoid osteoma is very effective
Clin Rad (2007). 62: 268-273
Akhlaghpoor S et al (Clinical Radiology 2007. 62:268-273 ) from Noor Medical Imaging Center, Iran treated 54 patients od osteoid osteoma with 11 G radiofrequency-compatible coaxial needle and 2 mm coaxial drill system and 1.0 cm active tip 17 G non-cooled radiofrequency needle. They performed RFA at 90 °C for 6 min. After needle removal, they injected 0.5–1.0 ml absolute alcohol into the nidus using a 20 G needle. The patients were discharged within 24 h.
They claim technical success rate of 100%. Complications occurred in about 4% (2 patients) and they were mild local cellulitis and small zone peripheral paresthesia. The follow-up period was in the range of 13–48 months. Pain relief and return to normal activities were seen in 52 of 54 patients (96%). Pain recurred in 2 patients after 1 and 3 months of pain free period. A second RFA and alcohol ablation was performed achieving successful results.
They concluded that the percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation was effective with high success rate and also persistent or recurrent lesions could be effectively re-treated.
Clin Rad (2007). 62: 268-273
Akhlaghpoor S et al (Clinical Radiology 2007. 62:268-273 ) from Noor Medical Imaging Center, Iran treated 54 patients od osteoid osteoma with 11 G radiofrequency-compatible coaxial needle and 2 mm coaxial drill system and 1.0 cm active tip 17 G non-cooled radiofrequency needle. They performed RFA at 90 °C for 6 min. After needle removal, they injected 0.5–1.0 ml absolute alcohol into the nidus using a 20 G needle. The patients were discharged within 24 h.
They claim technical success rate of 100%. Complications occurred in about 4% (2 patients) and they were mild local cellulitis and small zone peripheral paresthesia. The follow-up period was in the range of 13–48 months. Pain relief and return to normal activities were seen in 52 of 54 patients (96%). Pain recurred in 2 patients after 1 and 3 months of pain free period. A second RFA and alcohol ablation was performed achieving successful results.
They concluded that the percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation was effective with high success rate and also persistent or recurrent lesions could be effectively re-treated.
Cervical rib
Also known as Eve's rib
Usually from 7th cervical vertebra
Radiograph:
Rib arising from a horizontal transverse process (thoracic vertebrae show upward sloping transverse process)
0.5% of population
In 90% asymptomatic
Cervical rib syndrome
Cervical rib with pain and weakness of arm, swelling of the hand, variation in pulse intensity Angiograom may be useful
References:
Jeung MY et al. Imaging of Chest Wall Disorders. Radiographics. 1999;19:617-637
Usually from 7th cervical vertebra
Radiograph:
Rib arising from a horizontal transverse process (thoracic vertebrae show upward sloping transverse process)
0.5% of population
In 90% asymptomatic
Cervical rib syndrome
Cervical rib with pain and weakness of arm, swelling of the hand, variation in pulse intensity Angiograom may be useful
References:
Jeung MY et al. Imaging of Chest Wall Disorders. Radiographics. 1999;19:617-637
Pectus carinatum
Also known as pigeon chest
Abnormal anterior protrusion of sternum
Less common than excavatum
Associated with cyanotic congenital heart diseases
References:
Jeung MY et al. Imaging of Chest Wall Disorders. Radiographics. 1999;19:617-637
Abnormal anterior protrusion of sternum
Less common than excavatum
Associated with cyanotic congenital heart diseases
References:
Jeung MY et al. Imaging of Chest Wall Disorders. Radiographics. 1999;19:617-637
Avulsion injuries
Common in adolescents involved in sports
Classification:
Acute injuries: due to extreme, unbalanced, eccentric muscular contractions; associated with avulsed bone fragments
Subacute injuries: aggressive appearance of mixed lysis and sclerosis
Chronic injuries: due to repetitive microtrauma or overuse, may be associated with protuberant mass of bone
Imaging:
Plain radiographs: for avulsion fracture
CT: if equivocal radiographs
MR: evaluation of injuries to muscles, tendons, ligaments
Pelvis:
Iliac crest: abdominal muscles
ASIS: sartorius, tensor fascia lata
AIIS: rectus femoris
Inferior pubic ramus: adductiors, gracilis
Ischial tuberosity: hamstrings
Femur:
Greater trochonter: hip rotators
Lesser trochonter: iliopsoas
Around knee:
Lateral tibial plateau: lateral collateral ligament
Fibular head: lateral collateral ligamnet, biceps
Tibial eminence: ACL
Inferior pole of patella: patellar tendon
Tibial tuberosity: patellar tendon
Posterior tibial plateau: PCL
Gerdy tubercle: iliotibial band
Around ankle:
Posterior tibial avulsion: posterior capsular disruption
Base of 5th metatarsal: Peroneal tendon
Around shoulder:
Greater tuberosity: supraspinatus
Lesser tuberosity: subscapularis
Around elbow:
Avulsion of medial epicondyle = Little League elbow
References:
Stevens MA et al. Imaging Features of Avulsion Injuries. Radiographics. 1999;19:655-672
Image Gallery:
1. Right ASIS avulsion injury in 12 year old
Classification:
Acute injuries: due to extreme, unbalanced, eccentric muscular contractions; associated with avulsed bone fragments
Subacute injuries: aggressive appearance of mixed lysis and sclerosis
Chronic injuries: due to repetitive microtrauma or overuse, may be associated with protuberant mass of bone
Imaging:
Plain radiographs: for avulsion fracture
CT: if equivocal radiographs
MR: evaluation of injuries to muscles, tendons, ligaments
Pelvis:
Iliac crest: abdominal muscles
ASIS: sartorius, tensor fascia lata
AIIS: rectus femoris
Inferior pubic ramus: adductiors, gracilis
Ischial tuberosity: hamstrings
Femur:
Greater trochonter: hip rotators
Lesser trochonter: iliopsoas
Around knee:
Lateral tibial plateau: lateral collateral ligament
Fibular head: lateral collateral ligamnet, biceps
Tibial eminence: ACL
Inferior pole of patella: patellar tendon
Tibial tuberosity: patellar tendon
Posterior tibial plateau: PCL
Gerdy tubercle: iliotibial band
Around ankle:
Posterior tibial avulsion: posterior capsular disruption
Base of 5th metatarsal: Peroneal tendon
Around shoulder:
Greater tuberosity: supraspinatus
Lesser tuberosity: subscapularis
Around elbow:
Avulsion of medial epicondyle = Little League elbow
References:
Stevens MA et al. Imaging Features of Avulsion Injuries. Radiographics. 1999;19:655-672
Image Gallery:
1. Right ASIS avulsion injury in 12 year old
Anatomy: ankle ligaments
Lateral collateral ligament:
Anterior talofibular ligament: Best visualized on axial images
Posterior talofibular ligament: Best visualized on axial images
Calcaneofibular ligament: best seen on coronal plane, extends deep to peroneal tendons, from apex of lateral malleolus to small tubercle on lateral aspect of calcaneus
Medial collateral ligament (deltoid ligament):
Superficial layer:
Tibionavicular ligament
Tibiocalcaneal ligament: longest, 2 cm in length and 1cm wide at insertion
Tibiospring ligament
Deep layer:
Anterior talotibial ligament - weaker, thinner
Posterior talotibial ligament - strongest of the medial collateral ligament complex
Superficial layer is traingular, where as the deep layer is rectangular.
Deep layer is intra-articular, covered by synovium
Tibiofibular ligaments:
Anterior tibiofibular ligament
Posterior tibiofibular ligament
References:
Muhle C et al. Collateral Ligaments of the Ankle: High-Resolution MR Imaging with a Local Gradient Coil and Anatomic Correlation in Cadavers. Radiographics. 1999;19:673-683
Anterior talofibular ligament: Best visualized on axial images
Posterior talofibular ligament: Best visualized on axial images
Calcaneofibular ligament: best seen on coronal plane, extends deep to peroneal tendons, from apex of lateral malleolus to small tubercle on lateral aspect of calcaneus
Medial collateral ligament (deltoid ligament):
Superficial layer:
Tibionavicular ligament
Tibiocalcaneal ligament: longest, 2 cm in length and 1cm wide at insertion
Tibiospring ligament
Deep layer:
Anterior talotibial ligament - weaker, thinner
Posterior talotibial ligament - strongest of the medial collateral ligament complex
Superficial layer is traingular, where as the deep layer is rectangular.
Deep layer is intra-articular, covered by synovium
Tibiofibular ligaments:
Anterior tibiofibular ligament
Posterior tibiofibular ligament
References:
Muhle C et al. Collateral Ligaments of the Ankle: High-Resolution MR Imaging with a Local Gradient Coil and Anatomic Correlation in Cadavers. Radiographics. 1999;19:673-683
Rotator cuff injury
Pathogenesis:
Multifactoral - extrinsic and intrinsic
Extrinsic mechanism: Repitative microtrauma, Subacromial impingement, Macrotrauma - uncommon
Intrinsic mechanism: debatable change in vascularity
Important to remember:
Supraspinatus tendon is primarily involved in most
Tears usually begin near rotator interval
Partial tears are common on the articular surface
Subscapularis tears:
MR (both conventional and arthrographic) are not sensitive in the diagnosis of the articular surface partial thickness tears. (Sensitivity of noncontrast MRI - 40%, and MR arthrography - 36% - reference)
References:
Seibold C et al. Rotator Cuff: Evaluation with US and MR Imaging. Radiographics. 1999;19:685-705
Multifactoral - extrinsic and intrinsic
Extrinsic mechanism: Repitative microtrauma, Subacromial impingement, Macrotrauma - uncommon
Intrinsic mechanism: debatable change in vascularity
Important to remember:
Supraspinatus tendon is primarily involved in most
Tears usually begin near rotator interval
Partial tears are common on the articular surface
Subscapularis tears:
MR (both conventional and arthrographic) are not sensitive in the diagnosis of the articular surface partial thickness tears. (Sensitivity of noncontrast MRI - 40%, and MR arthrography - 36% - reference)
References:
Seibold C et al. Rotator Cuff: Evaluation with US and MR Imaging. Radiographics. 1999;19:685-705
Ewing's sarcoma
4th most common malignant bone tumor
2nd most common malignant bone tumor in pediatric age, most occur between 3 and 25 years (13 years average)
Female predilection - 2:1
Ribs:
10% occur in ribs
Propensity to spread inward towards thoracic cavity
May invade mediastinum, pericardium, diaphragm, spinal canal
Lytic or sclerotic or mixed
References:
Coombs RJ et al. Pediatric Case of the Day. Radiographics. 1999;19:241-244
2nd most common malignant bone tumor in pediatric age, most occur between 3 and 25 years (13 years average)
Female predilection - 2:1
Ribs:
10% occur in ribs
Propensity to spread inward towards thoracic cavity
May invade mediastinum, pericardium, diaphragm, spinal canal
Lytic or sclerotic or mixed
References:
Coombs RJ et al. Pediatric Case of the Day. Radiographics. 1999;19:241-244
Anatomy
TMJ
Shoulder and Arm:
Basics
Rotator cuff
Labrum
Glenohumoral ligaments
Wrist and hand:
TFCC anatomy
Hip and thigh:
Hamstring mucle complex
Knee and leg:
Menisci
Cruciate and collateral ligaments
Patellar ligaments and tendons
Posterolateral corner
Posterior muscles of the knee
Bursae of knee
Ankle and feet:
Ankle ligaments
Bones and joints
Peroneal compartment
Kager's fat pad
Lumbar spine:
Lumbar facet joints
Shoulder and Arm:
Basics
Rotator cuff
Labrum
Glenohumoral ligaments
Wrist and hand:
TFCC anatomy
Hip and thigh:
Hamstring mucle complex
Knee and leg:
Menisci
Cruciate and collateral ligaments
Patellar ligaments and tendons
Posterolateral corner
Posterior muscles of the knee
Bursae of knee
Ankle and feet:
Ankle ligaments
Bones and joints
Peroneal compartment
Kager's fat pad
Lumbar spine:
Lumbar facet joints
Anatomy: Lumbar facet joints
Anterosuperior articular facet from the vertebral body below and is concave
Posteroinferior articular facet from the vertebral body above and is convex
Oriented obliquely to sagittal plane
Joint space is curved from front to back
Covered by hyaline cartilage and have true synovial membrane, and hence involved in rheumatoid arthritis or ankylosing spondylitis.
Articular recesses:
Superior recess: located anteriorly, close to lumbar canal and neural elements, and may extend within intervertebral foramen.
Inferior recess: located posteriorly, no direct contact with neural elements
Increased lordosis widens superior recess, and kyphosis widens inferior recess
Nerve supply:
Rich sensory innervation by recurrent sensory nerve from ipsilateral posterior lumbar ramus at its own level and from the level above
References:
Sarazin L et al. Lumbar Facet Joint Arthrography with the Posterior Approach. Radiographics. 1999;19:93-104
Posteroinferior articular facet from the vertebral body above and is convex
Oriented obliquely to sagittal plane
Joint space is curved from front to back
Covered by hyaline cartilage and have true synovial membrane, and hence involved in rheumatoid arthritis or ankylosing spondylitis.
Articular recesses:
Superior recess: located anteriorly, close to lumbar canal and neural elements, and may extend within intervertebral foramen.
Inferior recess: located posteriorly, no direct contact with neural elements
Increased lordosis widens superior recess, and kyphosis widens inferior recess
Nerve supply:
Rich sensory innervation by recurrent sensory nerve from ipsilateral posterior lumbar ramus at its own level and from the level above
References:
Sarazin L et al. Lumbar Facet Joint Arthrography with the Posterior Approach. Radiographics. 1999;19:93-104
Pectus excavatum
Also known as funnel chest
Most common congenital deformity of sternum
Sternum is depressed so that ribs protrude anteriorly more than sternum itself
CXR frontal:
Indistinct right heart border
Decreased heart density
Left displacement of heart
Ribs show increase in downward angulation of anterior portions of ribs
Increased density in inferomedial right hemithorax
CXR lateral:
Shows position of sternum
CT:
Needed when surgical correction is considered
Pectus index = transverse diameter of the chest divided by AP diameter, more than 3.25 need surgical correction (normal is 2.31 to 2.91)
CT also useful in quantifying depression, asymmetry, flatness and in assessing the outcome of the procedure
References:
1. Kurihara Y et al. The Ribs: Anatomic and Radiologic Considerations.Radiographics. 1999;19:105-119
2. Jeung MY et al. Imaging of Chest Wall Disorders. Radiographics. 1999;19:617-637
Most common congenital deformity of sternum
Sternum is depressed so that ribs protrude anteriorly more than sternum itself
CXR frontal:
Indistinct right heart border
Decreased heart density
Left displacement of heart
Ribs show increase in downward angulation of anterior portions of ribs
Increased density in inferomedial right hemithorax
CXR lateral:
Shows position of sternum
CT:
Needed when surgical correction is considered
Pectus index = transverse diameter of the chest divided by AP diameter, more than 3.25 need surgical correction (normal is 2.31 to 2.91)
CT also useful in quantifying depression, asymmetry, flatness and in assessing the outcome of the procedure
References:
1. Kurihara Y et al. The Ribs: Anatomic and Radiologic Considerations.Radiographics. 1999;19:105-119
2. Jeung MY et al. Imaging of Chest Wall Disorders. Radiographics. 1999;19:617-637
Spondyloarthropathies: Approach in wrists
Wrist is not a single joint. For the purpose of Arthropathies, the wrist can be divided into following compartments:
1. Inferior radioulnar joint
2. Radiocarpal joint
3. Midcarpal joint
4. Pisiform-triquetral joint
5. Carpometacarpal joint
6. 1st CMCJ
RA:
Symmetrical
Initial coimpratments: radiocarpal, radioulnar, pisiform-triquetral
Eventually pancompartmental
Major damage occurs in distal ulna
JCA:
Midcarpal and common carpometacarpal compartments are predominalty involved with distal carpal migration
Eventual fusion of carpal bones and base of 2-5 metacarpals
relative sparing of the 1st CMCJ and radiocarpal joint
OA and erosive OA:
1st CMCJ with radial subluxation and trepizioscaphoid joints
CPPD:
Mimics OA
Radiocarpal joint is predominantly involved with narrowing of the joint space
Also midcarpal
Check lunotriquetral joint for chondrocalcinosis. This is more sensitive than TFCC for chondrocalcinosis
Radial erosions
Decrease in lunate-capitate space
Increase in scapholunate space
Destruction of trapezio-scaphoid joint
Chondrocalcinosis
Gout:
Predominant involvement of common carpometacarpal joints with erosions at the bases of metacarpals
CMCj may also be involved
Septic arthritis:
Never forget this in the differentials
Diffuse pancompartmental
Scleroderma:
Arthropathy in 1st CMCj with subluxation and calcification
SLAC:
Collapse of scapholunate space
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
1. Inferior radioulnar joint
2. Radiocarpal joint
3. Midcarpal joint
4. Pisiform-triquetral joint
5. Carpometacarpal joint
6. 1st CMCJ
RA:
Symmetrical
Initial coimpratments: radiocarpal, radioulnar, pisiform-triquetral
Eventually pancompartmental
Major damage occurs in distal ulna
JCA:
Midcarpal and common carpometacarpal compartments are predominalty involved with distal carpal migration
Eventual fusion of carpal bones and base of 2-5 metacarpals
relative sparing of the 1st CMCJ and radiocarpal joint
OA and erosive OA:
1st CMCJ with radial subluxation and trepizioscaphoid joints
CPPD:
Mimics OA
Radiocarpal joint is predominantly involved with narrowing of the joint space
Also midcarpal
Check lunotriquetral joint for chondrocalcinosis. This is more sensitive than TFCC for chondrocalcinosis
Radial erosions
Decrease in lunate-capitate space
Increase in scapholunate space
Destruction of trapezio-scaphoid joint
Chondrocalcinosis
Gout:
Predominant involvement of common carpometacarpal joints with erosions at the bases of metacarpals
CMCj may also be involved
Septic arthritis:
Never forget this in the differentials
Diffuse pancompartmental
Scleroderma:
Arthropathy in 1st CMCj with subluxation and calcification
SLAC:
Collapse of scapholunate space
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Spondyloarthropathies: Approach in Hands
RA:
Marginal and central bone erosions is important clue
Symmetric
Fusiform soft tissue swelling
Common: MCPJ, PIPJ, IPJ of thumb
Uncommon: DIPJ, rare in absence of proximal changes
Earliest: 2nd and 3rd MCPJ and 3rd PIPJ
Radial aspect of MC head (on ulnar side normaly there is a slight irregularity)
Periarticular osteoporosis
Uniform decrease in joint space
No osteophytes
OA:
Any articulation
PIP, DIP more common than MCP
Osteophyte is hallmark of the disease
Uniform decrease in joint space
Interdigitation is important feature (i.e. if there is decrease in joint space, it should also occur centrally). If there is increase in joint space centrally, it is unlikely to be OA
EOA: (Inflammatory OA)
Erosions not always present
PIP, DIP more common than MCP
Central collapse more than OA
JCA:
Advanced changes in relatively young patient is important clue
CPPD:
Symmetric
Features are similar to OA, but commonly involves MCP
MCPJ, most commonly 2nd and 3rd in hemochromatosis, and 4th and 5th in idiopathic CPPD ??
Beak like osseous growths from radial aspect of metacarpal heads in hemochromatosis
Psoriasis:
DIPJ involvement is important clue - 'pencil in cup'
Single ray involvement is a feature
Whiskering is an important sign = proliferative arthropathy
Erosions tend to go peripherally
Periarticular osseous proliferation
Periostitis
Asymmetric
Minimal osteoporosis
Scleroderma:
DIPJ and to lesser extent PIPJ involvement with soft tissue calcification is important clue
Acroosteolysis is another important clue
Gout:
Asymmetric
DIPJ, PIPJ, MCPJ
Lobulated soft tissue masses, eccentric punched out extremely well defined erosions with overhanging edges are important clues
Joint space is usually preserved
No porosis
SLE:
Deforming non-erosive arthropathy is important clue
Symmetric
MCPJ and IPJ of all digits
Osteonecrosis at MCPJs
Radiographs may be normal even if there is clinically visible deformity. It is because as soon as the patient keeps the hand on the cassette, the deformity gets corrected!
Reiter's:
Similar to psoriasis
AS:
Exuberant osseous proliferation is important clue
Asymmetric
DIPJ may be involved
Also affects PIPJ, MCPJ, IPJ of thumb
Polymyositis:
Similar to scleroderma
Multicentric reticulohistiocytosis:
Extremely well defined erosions
I was listening to Dr Resnick when he told (Lords, London, 2007) that he has seen 2 or 3 cases of MRH in his life time. So never make a diagnosis of MRH, unless you know the histological diagnosis!!
Jaccouds arthropathy:
Rare
Associated with rheumatic fever
Non-erosive reversible arthropathy
Hyperparathyroidism:
Although not an arthritidis, never forget hyperparathyroidism in the differentials.
Subperiosteal or subchondral bone resorption
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Marginal and central bone erosions is important clue
Symmetric
Fusiform soft tissue swelling
Common: MCPJ, PIPJ, IPJ of thumb
Uncommon: DIPJ, rare in absence of proximal changes
Earliest: 2nd and 3rd MCPJ and 3rd PIPJ
Radial aspect of MC head (on ulnar side normaly there is a slight irregularity)
Periarticular osteoporosis
Uniform decrease in joint space
No osteophytes
OA:
Any articulation
PIP, DIP more common than MCP
Osteophyte is hallmark of the disease
Uniform decrease in joint space
Interdigitation is important feature (i.e. if there is decrease in joint space, it should also occur centrally). If there is increase in joint space centrally, it is unlikely to be OA
EOA: (Inflammatory OA)
Erosions not always present
PIP, DIP more common than MCP
Central collapse more than OA
JCA:
Advanced changes in relatively young patient is important clue
CPPD:
Symmetric
Features are similar to OA, but commonly involves MCP
MCPJ, most commonly 2nd and 3rd in hemochromatosis, and 4th and 5th in idiopathic CPPD ??
Beak like osseous growths from radial aspect of metacarpal heads in hemochromatosis
Psoriasis:
DIPJ involvement is important clue - 'pencil in cup'
Single ray involvement is a feature
Whiskering is an important sign = proliferative arthropathy
Erosions tend to go peripherally
Periarticular osseous proliferation
Periostitis
Asymmetric
Minimal osteoporosis
Scleroderma:
DIPJ and to lesser extent PIPJ involvement with soft tissue calcification is important clue
Acroosteolysis is another important clue
Gout:
Asymmetric
DIPJ, PIPJ, MCPJ
Lobulated soft tissue masses, eccentric punched out extremely well defined erosions with overhanging edges are important clues
Joint space is usually preserved
No porosis
SLE:
Deforming non-erosive arthropathy is important clue
Symmetric
MCPJ and IPJ of all digits
Osteonecrosis at MCPJs
Radiographs may be normal even if there is clinically visible deformity. It is because as soon as the patient keeps the hand on the cassette, the deformity gets corrected!
Reiter's:
Similar to psoriasis
AS:
Exuberant osseous proliferation is important clue
Asymmetric
DIPJ may be involved
Also affects PIPJ, MCPJ, IPJ of thumb
Polymyositis:
Similar to scleroderma
Multicentric reticulohistiocytosis:
Extremely well defined erosions
I was listening to Dr Resnick when he told (Lords, London, 2007) that he has seen 2 or 3 cases of MRH in his life time. So never make a diagnosis of MRH, unless you know the histological diagnosis!!
Jaccouds arthropathy:
Rare
Associated with rheumatic fever
Non-erosive reversible arthropathy
Hyperparathyroidism:
Although not an arthritidis, never forget hyperparathyroidism in the differentials.
Subperiosteal or subchondral bone resorption
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
TMJ anatomy
Unusual synovial joint where articular surfaces are covered with fibrocartilage, not hyaline cartilage.
Bones:
Temporal bone: Articular eminence anteriorly and posterior glenoid tubercle posteriorly, in between is the glenoid fossa
Mandible: Condylar head of the mandible articulates with glenoid fossa
Articular disc (meniscus):
Divides the joint into superior and inferior compartments
Biconcave fibrocartilage
Divides synovial joint into superior and inferior compartments
Round to oval in shape with a thin intermediate zone which separates thicker peripheral anterior and posterior bands
Anterior band:
Smaller than posterior band
Attached to joint capsule, condylar head, anterior margin of articular eminence, anteroinferior aspect of the condylar articular margin, superior belly of lateral pterygoid muscle
Intermediate zone:
Between anterior and posterior band
Posterior band:
Blends with bilaminar zone (areolar tissue, retrodiscal tissue, posterior ligament)
Bilaminar zone:
Synonyms: areolar tissue, retrodiscal tissue, posterior ligament
Rich neurovascular tissue
Attaches to mandibular condyle and temporal bone
MR disc anatomy:
Biconcave structure with homogeneous low signal intensity
Low signal on T1 and T2
Intermediate zone might show increased T2 signal
Attached posteriorly to bilaminar zone, which has intermediate signal
Posterior band and retrodiskal tissue are best seen on the open-mouth views
Anterior band and intermediate zone are of low signal and posterior band is slightly of high signal
Anterior band lies anterior to condyle
Movements:
1. Rotation around horizontal axis through condylar heads
2. Translation: condyle and meniscus move together anteriorly beneath articular eminence; In open mouth, the condyle lies beneath anterior band of the meniscus
Mouth opening is by lateral pterygoid muscle
Mouth closing is by medial pterygoid, temporalis and messeter
Closed-mouth:
Posterior band lies above condyle (12 o' clock)
Junction of posterior band and bilaminar within 10° of vertical (if the angle exceeds 10°, it may be pathological) (Figure: Radiographics link here)
Anterior disk displacement of up to 30° can be normal
Figures:
Normal anatomy: Link to Radiographics
References:
1. Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
2. Tomas X et al. MR Imaging of Temporomandibular Joint Dysfunction: A Pictorial Review. RadioGraphics 2006;26:765-781
Bones:
Temporal bone: Articular eminence anteriorly and posterior glenoid tubercle posteriorly, in between is the glenoid fossa
Mandible: Condylar head of the mandible articulates with glenoid fossa
Articular disc (meniscus):
Divides the joint into superior and inferior compartments
Biconcave fibrocartilage
Divides synovial joint into superior and inferior compartments
Round to oval in shape with a thin intermediate zone which separates thicker peripheral anterior and posterior bands
Anterior band:
Smaller than posterior band
Attached to joint capsule, condylar head, anterior margin of articular eminence, anteroinferior aspect of the condylar articular margin, superior belly of lateral pterygoid muscle
Intermediate zone:
Between anterior and posterior band
Posterior band:
Blends with bilaminar zone (areolar tissue, retrodiscal tissue, posterior ligament)
Bilaminar zone:
Synonyms: areolar tissue, retrodiscal tissue, posterior ligament
Rich neurovascular tissue
Attaches to mandibular condyle and temporal bone
MR disc anatomy:
Biconcave structure with homogeneous low signal intensity
Low signal on T1 and T2
Intermediate zone might show increased T2 signal
Attached posteriorly to bilaminar zone, which has intermediate signal
Posterior band and retrodiskal tissue are best seen on the open-mouth views
Anterior band and intermediate zone are of low signal and posterior band is slightly of high signal
Anterior band lies anterior to condyle
Movements:
1. Rotation around horizontal axis through condylar heads
2. Translation: condyle and meniscus move together anteriorly beneath articular eminence; In open mouth, the condyle lies beneath anterior band of the meniscus
Mouth opening is by lateral pterygoid muscle
Mouth closing is by medial pterygoid, temporalis and messeter
Closed-mouth:
Posterior band lies above condyle (12 o' clock)
Junction of posterior band and bilaminar within 10° of vertical (if the angle exceeds 10°, it may be pathological) (Figure: Radiographics link here)
Anterior disk displacement of up to 30° can be normal
Figures:
Normal anatomy: Link to Radiographics
References:
1. Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
2. Tomas X et al. MR Imaging of Temporomandibular Joint Dysfunction: A Pictorial Review. RadioGraphics 2006;26:765-781
TMJ
Anatomy
TMJ dysfunction
Journal review:
Seminars in Ultrasound, CT, and MRI. Volu 28, issue 3. 169-222 is dedicated to TMJ imaging.
TMJ dysfunction
Journal review:
Seminars in Ultrasound, CT, and MRI. Volu 28, issue 3. 169-222 is dedicated to TMJ imaging.
THR: Heterotopic bone formation
Brooker grading:
Class I: Islands of bones
Class II: more than 1 cm between two bone surfaces
Class III: less than 1 cm between two bone surfaces
Class IV: Bony ankylosis
References:
Brooker AF et al. Ectopic ossification following total hip replacement. Incidence and method of a classification. J Bone Joint Surg Am 55: 1629, 1973
Class I: Islands of bones
Class II: more than 1 cm between two bone surfaces
Class III: less than 1 cm between two bone surfaces
Class IV: Bony ankylosis
References:
Brooker AF et al. Ectopic ossification following total hip replacement. Incidence and method of a classification. J Bone Joint Surg Am 55: 1629, 1973
THR: aggresive granumomatous disease
Also known as cement disease, particle disease, aggresive osteolysis
Extensive bone resorption due to hypersentitivity and gaint cell reaction
Radiograph:
Well defined lytic lesions, which do not follw the shape of the prosthesis
Common at the tip or medial border of the femoral component
Also seen in acetabulum
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Extensive bone resorption due to hypersentitivity and gaint cell reaction
Radiograph:
Well defined lytic lesions, which do not follw the shape of the prosthesis
Common at the tip or medial border of the femoral component
Also seen in acetabulum
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
THR infection
Radiograph:
Rapidly increasing bone-cement gap
Endosteal scalloping
Periosteal reaction
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Rapidly increasing bone-cement gap
Endosteal scalloping
Periosteal reaction
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
THR loosening
Most common cause of THR failure
Acetabular loosening incereases with time
Improvement in technque have reduced femoral lossening
Radiography:
Lucency between cement and bone more than 2 mm
Prosthetic migration
Cement fracture
Peristeal reaction
Arthrography:
Acetabular loosening: 90% sensitive, 70% specific
Contrast in all zones, I & II, II & III, or I & III with pseudocapsule or bursa (there are 3 zones divided by 2 perpendicular lines drawn from the centre of the acetabulur line; the lateral is zone I, middle zone II and medial zone III)
Contrast more than 2 mm thick in any zone
Femoral lossening: 90% sensitive and specific
Contrast below intertrochontric line
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Acetabular loosening incereases with time
Improvement in technque have reduced femoral lossening
Radiography:
Lucency between cement and bone more than 2 mm
Prosthetic migration
Cement fracture
Peristeal reaction
Arthrography:
Acetabular loosening: 90% sensitive, 70% specific
Contrast in all zones, I & II, II & III, or I & III with pseudocapsule or bursa (there are 3 zones divided by 2 perpendicular lines drawn from the centre of the acetabulur line; the lateral is zone I, middle zone II and medial zone III)
Contrast more than 2 mm thick in any zone
Femoral lossening: 90% sensitive and specific
Contrast below intertrochontric line
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
THR: radiographic appearance
Component position:
1. Acetabular inclination: Angle between horizonatl base line and actabular orifice is usually 40-50 degrees. More angle = verticle inclination, less angle = horizaontal inclination
2. Acetabular anteversion: on true lateral view, angle between axis of acetabulum and a line perpendicular to the base line
2. Verticle position of the femur: Perpendicluar distance between centre of hip and interteardrop line
3. Mediolateral position of the femur: Distance between centre of hip and interteardrop line
4. Femoral stem: should be within the centre of medullar canal or slightly medially.
5. Length: Distance between proximal edge of lesser trochonter and base of ischial tuberosity
Component fixation:
Lucent lines between cement and bone usually stabilise in 2 years, measuring 0.1 to 1.5 mm. More 2 mm indicates loosening.
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
1. Acetabular inclination: Angle between horizonatl base line and actabular orifice is usually 40-50 degrees. More angle = verticle inclination, less angle = horizaontal inclination
2. Acetabular anteversion: on true lateral view, angle between axis of acetabulum and a line perpendicular to the base line
2. Verticle position of the femur: Perpendicluar distance between centre of hip and interteardrop line
3. Mediolateral position of the femur: Distance between centre of hip and interteardrop line
4. Femoral stem: should be within the centre of medullar canal or slightly medially.
5. Length: Distance between proximal edge of lesser trochonter and base of ischial tuberosity
Component fixation:
Lucent lines between cement and bone usually stabilise in 2 years, measuring 0.1 to 1.5 mm. More 2 mm indicates loosening.
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Ulnar variance
Positive ulnar variance (ulnar plus):
Articular surface of ulna projects distal to that of the radius
Associated with ulnocarpal abutment syndrome
Negative ulnar variance (ulnar minus):
Relatively short ulna
Associated with Keinbocks disease
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Articular surface of ulna projects distal to that of the radius
Associated with ulnocarpal abutment syndrome
Negative ulnar variance (ulnar minus):
Relatively short ulna
Associated with Keinbocks disease
 |
| Negative Ulnar Variance |
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Sesemoid bones
Type A:
Adjacent to joint, tendon is within the joint capsule
e.g. patella, 1st MCPJ sesemoids (2 in number, within the tendons of adductor pollicis and FPB)
Type B:
At the level of angling of the tendons, seperated from bone by synovial lined bursa
e.g. common in feet, peroneaus longus sesemoid
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Adjacent to joint, tendon is within the joint capsule
e.g. patella, 1st MCPJ sesemoids (2 in number, within the tendons of adductor pollicis and FPB)
Type B:
At the level of angling of the tendons, seperated from bone by synovial lined bursa
e.g. common in feet, peroneaus longus sesemoid
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Joints: General points
Classification based on joint mobility:
Synarthrosis: rigid joints
Amphiarthrosis: minimally mobile joints
Diarthrosis: freely mobile joints
Classification based on histology:
Fibrous: connected by fibrous connective tissue
1. Suture: skull
2. Syndesmosis: distal radioulnar joint, radioulnar interosseuous membrane, sacroiliac interosseous ligament
3. Gomphosis: teeth
Cartilagenous: connected by cartilagenous tissue
1. Symphysis: symphysis pubis, intervertebral disc, manubriosternal joint, central mandible
2. Synchondrosis: growth plate, neurocentral joint, spheno-occipital joint
Synovial: Articular cavity with synovial lining
1. All extremity joints
2. Sacroiliac joint
3. Apophyseal joint
4. Costovertebral joint
5. Sterenoclavicular joint
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Synarthrosis: rigid joints
Amphiarthrosis: minimally mobile joints
Diarthrosis: freely mobile joints
Classification based on histology:
Fibrous: connected by fibrous connective tissue
1. Suture: skull
2. Syndesmosis: distal radioulnar joint, radioulnar interosseuous membrane, sacroiliac interosseous ligament
3. Gomphosis: teeth
Cartilagenous: connected by cartilagenous tissue
1. Symphysis: symphysis pubis, intervertebral disc, manubriosternal joint, central mandible
2. Synchondrosis: growth plate, neurocentral joint, spheno-occipital joint
Synovial: Articular cavity with synovial lining
1. All extremity joints
2. Sacroiliac joint
3. Apophyseal joint
4. Costovertebral joint
5. Sterenoclavicular joint
References:
Resnick et al, Bone and joint imaging, 3rd edition, Elsevier Saunders publications
Locked metacarpophalyngeal joint
Causes:
Tears of collateral ligaments or volar plate
Impingement by osteophytes, irregular articular surfaces, loose bodies, soft tissue bands
Entrapment of radial collateral ligament, sesamoid bone, exostosis
Epidemiology:
Index and middle fingers
Equal in men and women
Types:
Spontaneous
Degenerative: >50 years, middle finger prediliction
Treatment:
Closed manipulation - rarely successful
Usually requires surgery - resection of prominence on metacarpal head
Reference:
Thomas RJ et al. Locked Metacarpophalangeal Joint in a 20-Year-Old Football Player. The American Journal of Sports Medicine 34:29-31 (2006)
Tears of collateral ligaments or volar plate
Impingement by osteophytes, irregular articular surfaces, loose bodies, soft tissue bands
Entrapment of radial collateral ligament, sesamoid bone, exostosis
Epidemiology:
Index and middle fingers
Equal in men and women
Types:
Spontaneous
Degenerative: >50 years, middle finger prediliction
Treatment:
Closed manipulation - rarely successful
Usually requires surgery - resection of prominence on metacarpal head
Reference:
Thomas RJ et al. Locked Metacarpophalangeal Joint in a 20-Year-Old Football Player. The American Journal of Sports Medicine 34:29-31 (2006)
Cuboid dislocation
Introduction:
Rigid and static stabilizer of lateral column of foot.
Only bone to articulate with both midtarsal and tarsometatarsal joints
Aattachments are dorsal and plantar ligaments, peroneus longus, plantar fascia
Dislocation:
Uncommon.
Usually require open reduction
References:
Smith JS et al. Complete Cuboid Dislocation in a Professional Baseball Player. The American Journal of Sports Medicine 34:21-23 (2006)
Rigid and static stabilizer of lateral column of foot.
Only bone to articulate with both midtarsal and tarsometatarsal joints
Aattachments are dorsal and plantar ligaments, peroneus longus, plantar fascia
Dislocation:
Uncommon.
Usually require open reduction
References:
Smith JS et al. Complete Cuboid Dislocation in a Professional Baseball Player. The American Journal of Sports Medicine 34:21-23 (2006)
Journal Watch: Hamstring strain
MRI predicts the time to return to pre-injury level in hamstring injuries:
The American Journal of Sports Medicine 35:197-206 (2007)
'Acute First-Time Hamstring Strains During High-Speed Running - A Longitudinal Study Including Clinical and Magnetic Resonance Imaging Findings' was performed by Askling CM et al in 18 sprinters. All underwent clinical examination and MRI at day 2 to 4, 10, 21, and 42 and clinically followed for 2 years. The primary injuries were in the long head of the biceps.
Conclusion:
1. MRI performed during the first 6 weeks after injury provides a valuable information in the prediction of the time to return to pre-injury level of performance in elite sprinting.
2. The more proximal the injury, the longer the time to return to pre-injury level.
The American Journal of Sports Medicine 35:197-206 (2007)
'Acute First-Time Hamstring Strains During High-Speed Running - A Longitudinal Study Including Clinical and Magnetic Resonance Imaging Findings' was performed by Askling CM et al in 18 sprinters. All underwent clinical examination and MRI at day 2 to 4, 10, 21, and 42 and clinically followed for 2 years. The primary injuries were in the long head of the biceps.
Conclusion:
1. MRI performed during the first 6 weeks after injury provides a valuable information in the prediction of the time to return to pre-injury level of performance in elite sprinting.
2. The more proximal the injury, the longer the time to return to pre-injury level.
Journal watch: ACL
ACL reconstruction cannot restore tibial rotation to normal levels
The American Journal of Sports Medicine 35:189-196 (2007)
Chouliaras V et al studied 'Effectiveness of reconstruction of the Anterior Cruciate Ligament with Quadrupled Hamstrings and Bone-Patellar Tendon-Bone Autografts' comparing the tibial internal-external Rotation. The kinematic data of tibial internal-external rotation were assessed in 11 patients with patellar tendon graft, 11 with hamstring tendon graft and 11 controls using a 6-camera optoelectronic system when the subjects descended stairs and, immediately after, pivoted on their landing leg. Also, all patients were also assessed clinically and with KT-1000 arthrometer to evaluate anterior tibial translation. Both grafts successfully restored anterior tibial translation, but showed increased tibial rotation when compared to controls, and no differences between the 2 reconstructed groups.
Conclusion:
The 2 most frequently used autografts for ACL reconstruction cannot restore tibial rotation to normal levels.
The American Journal of Sports Medicine 35:189-196 (2007)
Chouliaras V et al studied 'Effectiveness of reconstruction of the Anterior Cruciate Ligament with Quadrupled Hamstrings and Bone-Patellar Tendon-Bone Autografts' comparing the tibial internal-external Rotation. The kinematic data of tibial internal-external rotation were assessed in 11 patients with patellar tendon graft, 11 with hamstring tendon graft and 11 controls using a 6-camera optoelectronic system when the subjects descended stairs and, immediately after, pivoted on their landing leg. Also, all patients were also assessed clinically and with KT-1000 arthrometer to evaluate anterior tibial translation. Both grafts successfully restored anterior tibial translation, but showed increased tibial rotation when compared to controls, and no differences between the 2 reconstructed groups.
Conclusion:
The 2 most frequently used autografts for ACL reconstruction cannot restore tibial rotation to normal levels.
Journal Watch: Peroneal compartment
Peroneus quartus is seen in 17% and retrotrochlear eminence in all:
Radiology 2007;242:509-517
Saupe N et al studies 'Anatomic variants associated with peroneal tendons' in 65 volunteers (35 women, 30 men; age range, 23–70 years; median age, 45 years). Peroneus quartus was identified in 11 (17%). Retrotrochlear eminence was seen in all ankles.
Radiology 2007;242:509-517
Saupe N et al studies 'Anatomic variants associated with peroneal tendons' in 65 volunteers (35 women, 30 men; age range, 23–70 years; median age, 45 years). Peroneus quartus was identified in 11 (17%). Retrotrochlear eminence was seen in all ankles.
Journal Watch
This section contains abstracts from various radiology, orthopaedic, rheumatology and emergency radiology journals.
Hip and thigh:
Hamstring strain
Knee and leg:
ACL
Patellar tendon
SONK
Knee chondral lesions
Ankle & Foot:
Peroneal compartment
Achillis tendon
Tumour and tumour like conditions:
Osteoid osteoma
Hip and thigh:
Hamstring strain
Knee and leg:
ACL
Patellar tendon
SONK
Knee chondral lesions
Ankle & Foot:
Peroneal compartment
Achillis tendon
Tumour and tumour like conditions:
Osteoid osteoma
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