Prism - Biomechanics Flashcards
What is the normal hallux interphalangeal angle?
0-10 degrees
What is the normal DASA/PASA angle?
<7.5
What is a structural deformity of a bunion regarding pasa and dasa?
If PASA + DASA = Hallux angle think structural.
AKA there is a problem with the actual cartilage heads.
If PASA + DASA is less than the hallux angle then it is considered positonal.
If PASA and DASA are outside of normal limits (>7.5) but still dont match the HA then it is a combo of positional and structural issues.
Describe how joint lines differ between a subluxed and deviated joint.
Deviated: Joint lines converge outside of the joint
Subluxed: The joint lines converge inside of the joint.
What is the normal hallux abductus angle?
<15 degrees
This is how much the hallux drifts laterally.
What is considered a normal Intermetarsal angle?
8-12 degrees
What IM angle should be corrected with a metatarsal head correction?
10-13 degrees
What IM angle should be corrected with a metatarsal shaft procedure?
14-17 degrees
What IM angle should be corrected with a base procedure?
18-21 degrees
When should a lapidus procedure be considered for a bunion?
With hypermobility.
What is the normal metatarsus adductus angle?
<20 degrees
How does one determine the true intermetatarsal angle if there is met adductus?
True angle = (Met adductus angle -15) + IM angle.
What is the normal first metatarsal protrusion angle?
Normal +/- 2mm compared to the second metatarsal.
What is the normal tibial sesamoid position?
Normal 1-3
What is the normal ROM at the hallux MPJ?
Normal 65-75 degrees of dorsiflexion and 40 degrees of plantarflexion
What is the normal first metatarsal-medial cuneiform angle?
22 degrees
What is the normal ROM for the first ray?
Normal is 5mm dorsiflexion with 5mm plantarflexion
This equates to 1 cm total rom.
What is the Fallat and Buckholz 4th IM angle?
Angle between the bisection of the 4th met and the proximal-medial cortical border of the 5th metatarsal.
normal is 6 degrees
Pathological is >8.7 degrees.
What is the Fallat and Buckholz Lateral deviation angle?
Also known as the lateral bowing angle
Angle of line bisecting head and neck of 5th met and line adjacent to proximal-medial cortex.
Normal is 2.64 degrees
Pathologic is >8 degrees
List the met length order from longest to shortest
Longest 2>3>5>4>1 Shortest
List the metatarsal protrusion length from longest to shortest
Longest 2 > 3> 1> 4 > 5 Shortest
What is the ROM of the lesser MPJ?
30-40 degrees of dorsiflexion
50-60 degrees of plantarflexion
What is the normal metatarsal declination angle?
Normal is 21 degrees
What is the normal metatarsal abductus angle?
Normal 0-15
What is the normal IM angle of the second and 5th metatarsals?
14-18
What IM angle between the first and second mets is considered pathologic?
Anything greater than 12 degrees.
normal is 8-12 degrees.
What is Splay foot?
Increased 1st IM angle >12 with an increased 4th IM >8
With metatarsus primus adductus, there is a high predilection of splayfoot
What is the normal long axis of the metatarsal head and neck with long axis of the talar body angle?
In adult vs at birth?
130-140 at birth
Adult 150-165
What is the normal ammount of plantarflexion noted in the talar neck?
25-30 degrees
How far medially is the talar head normally aligned?
15 degrees
What is the normal talar declination angle?
21 degrees
What forms the cyma line?
The TN and CC joints
How is the cyma line aligned in pronation?
The cyma line will sit anteriorly
How is the cyma line aligned with supination?
The cyma line will sit posteriorly.
What is the normal TN coverage?
75 degrees of coverage
Or 25 degrees of uncovered head.
What is the normal amount of forefoot abductus?
8 degrees (0-15)
What is the normal calcaneal inclination angle?
21 degrees
What is Hibb’s angle?
Seen on a lateral view only
I{t is the intersection of the longitudinal axis of the calcaneus and the first metatarsal
What is the fowler phillip angle?
Angle formed from the intersection of a line along the anterior tubercle and the plantar tuberosity and another line along the posterosuperior proiminence at the achilles tendon insertion.
Normal is 70 degrees
Haglunds deformity >75 degrees
What is the total angle of Ruch?
It is the calcaneal fowler and philip angle added to the calcaneal inclination angle.
normal is 90 degrees
Haglunds deformity will be greater than that 90 degrees.
What is the normal calcanel cuboid abduction angle?
Normal 0-5
Increases with pronation.
What is a normal kites angle in an adult?
20-40 degrees
Increases with pronation
Decreases with supination
What is a normal kites angle in a child?
30-50 degrees
Increases with pronation
decreases with supination
What is the normal talocalcaneal angle?
Seen on the lateral view only
Normal is 25-40 degrees and this does not change with age.
What is the direction of the STJ axis?
Normal?
Pronation?
supination?
Through the first ray in neutral
2nd ray when supinating
medial to the 1st ray in pronation
What is the STJ axis of motion (Planes)
Lateral, posterior, plantar, to medial anterior dorsal.
48 degrees from the frontal plane
42 degrees from the transverse plane
16 degrees from the sagittal plane
Which direction does the oblique midtarsal joint run?
38 degrees from frontal plane
52 degrees from transverse plane
57 degrees from the sagittal plane
What does Bohlers angle check?
Angle formed by the intersection of a line from the superior aspect of the anterior process to the superior aspect of the posterior facet and another line from the superior aspect of the posterior facet to the superior point of the calcaneal process
Normal 25-40
Decreases with intraarticular calcaneal fractures.
What does Gissanes angle check?
Angle formed by the intersection of a line along the posterior facet and another line along the middle and anterior facets
Normal is 125-140 degrees
Increases with intraarticular calcaneal fractures.
What is Toyger angle?
A line drawn down the posterior aspect of the calcaneus
Normally the line should be straight (180 degrees)
Decreases with an achilles rupture!!
What is the normal ROM of the ankle?
10-20 degrees of dorsiflexion
20-40 degrees of plantarflexion
What is the normal axis of the ankle joint?
Lateral posterior plantar to medial anterior dorsal
What is the normal tibial torsion positon in children vs adults?
In children it is 13-18 degrees (6 yrs)
In adults its 18-23 degrees
What is the normal tibial varum/valgum??
Tibial varum: is seen at birth with 5-10 degrees
Tibial valgum is the final position as an adult >2-3 years and is 2-3 degrees of valgum.
What is the normal ROM of hip flexion extension?
Normally flexion is 90-100 degrees with the knee extended
Normal extension is 10-20 degrees with the knee extended.
What is the Ortolani test?
Tests for congenital hip dislocation in new borns
While the newborn is supine and hip and knees flexed, the hips are adducted while pressing downward and abducted while lifting upward.
An unstable hip will dislocate when adducted and reduce when abducted.
