NUC RAD SHARE

BONE RADIOLOGY

 
bone xray1
bone xray2

BONE XRAY NORMAL MEASUREMENTS

 

SKULL

 

Sella turcica

 length (AP) 5-16mm and depth 4-12mm on lateral view

C-SPINE

 

 

Craniocervical jct

Powers ratio (BC/OA) >1 (BC=basion to post C1 arch/Opisithon to tip of dens)

Basion to dental interval <12mm

Basilar impression

Tip of dens ≥6.6mm above Chamberlain line (btwn hard palate to opisithon on lateral view)

C1 lateral mass

on odontoid view normally ≤2mm displacement (if >7mm, transverse ligament most likely torn)

Atlantoaxial distance

≤3mm (adult); ≤5mm (kids)

C2-3 pseudosubluxation (<8-16yo) <2mm from spinolaminar line

Prevertebral ST

≤10mm at C1, ≤7mm at C2-4, and ≤22mm (≤14mm kids) at C5-7

(some say 6mm at C2 or 22mm at C6)

Peds prevertebral ST: <1/2 vert body width up to C3 and <1 vert body width C4-7

 

Canal diameter

Post vert body to Spinolaminar (lateral view) “canal” dia: C1 (20-33mm), C2 (15-29mm), C3-7 (15-24mm)

Congenital cervical spinal canal stenosis AP dia <10-13mm

 

ROM

ROM btwn flexion and extension 19-54deg

Disk space

Largest at C6-7

Unstable C-spine fx

-vert compression >25%

-anterolisthesis >3.5mm

-widened/narrowed disc space

-widened apophyseal jt

-widened interspinous space

-focal angulation >110deg

 -≥2 columns involved

SHOULDER

 

AC distance

≤7mm

CC distance

≤11mm

Sternocalvicular jt

width 3-5mm

CHEST

 

PECTUS EXCAVATUM

Haller index ~2.5 (>3.2 indication for surgical correction)

ELBOW

 

C-R-I-T-O-E

1-3-5-7-9-11yo

Carrying angle

humeroulnar angle = 165-170deg

HAND/WRIST

 

 

Scapholunate angle

30-60deg (capitolunate angle ≤20deg)

DISI >60deg (capitolunate angle >20deg)

VISI <30deg (capitolunate angle >20deg)

Rotary subluxation of scaphoid >60deg

Radiocarpal jt

width 2.0-2.5mm

Metacarpal sign

line tangential from 4th/5th MT heads should not touch 3rd MC head otherwise have shortened 4th MC

T-SPINE

 

Scoliosis

cobb angle <10deg; >30deg is severe

Kyphosis angle

T3 and T11 on lateral <25-40deg

Left paravertebral line

AP chest from T4 thru T11: 6-8mm (<40yo); 6-15mm (>40yo)

Disk space

Largest at T11-T12

L-SPINE

 

Interpedicular distance

>16mm

Canal diameter

>11mm on lateral view

ROM

btwn flexion and extension 64-80deg (Bakke)

DISK SPACE

Largest at L4-5

PELVIS/HIP

 

Femur CCD angle

femoral neck to diaphysis angle 120-130deg

FAI

Lateral center-edge angle 25-39deg (>39deg suggest pincer-type FAI) on AP

Alpha angle ≤55deg (>55deg suggest CAM-type FAI) on cross-table lateral

Coxa profunda vs acet protusio vs acet overcoverage vs acet retroversion (figure of 8) for pincer-type FAI

Dysplastic bump at lateral head-neck jct for CAM-type FAI

DDH

Acetabular angle <30deg (alpha angle ≥60deg on ultrasound)

Hip jt space

width 4-5mm

Pubic symphysis

Width ≤6mm

Sacroiliac jt

width ≤3-4mm

Pelvic measurement

Pelvic inlet view: AP dia (from S1 to PS) ~9.5-11.5cm; Transverse dia ~11-13cm

 

Fat stripes

gluteus minimus (lateral), iliopsoas (medial), obturator internus (pelvis)

KNEE

 

Mechanical axis

From center of femoral head to center of ankle jt should pass thru middle knee jt

Q angle

Femur to Tibia angle ~15deg

Lat femoral notch

≤2mm (otherwise, deep lat femoral notch)

Alignment

Distal femur normally in 5-7deg valgus

Proximal tibia normally in 2-3deg varus

Femorotobial jt

Width 3-5mm

Patellofemoral jt

4mm

Patellar tendon

Patellar tendon to patella ratio= 0.8-1.2 on 30deg flexed lateral view (>1.3=alta)

ANKLE

 

Ankle mortise

Medial clear space ≤4mm (>4mm abnormal)

Lateral clear space <5mm (abnormal ≥5mm) measured 1cm above plafond; tib-fib overlap ≥1cm

Stress views

AP inversion/adduction: apperture btwn tibia and talus (AP) <5deg normal, btwn 5-10deg equivocal, >10deg abnl

Lat ant drawer: talar advancement (lat) <5mm nl, btwn 5-10mm equivocal, >10mm abnl

Boehler’s angle

28-40deg (lateral)

Heel fat pad

≤23-25mm

FOOT

 

Pes planus

Calcaneal pitch 18-20deg

Hallus valgus

Normal <15deg (mild=16-25deg; mod=26-35; severe>35deg)

Intermetatarsal angle (btwn 1st/2nd MT) <10deg

Bunionette

Intermetatarsal angle (btwn 4th/5th MT) ≤8deg; width of 5th MT head <13mm; varus MTP jt

Accessory os

Os naviculare (medial); Os peroneum (lateral); Os trigonum (posterior)

 



     
Bone radiology normal measurements