Elbow Complex Flashcards
Bones (3}) and joints (4) of the Elbow Complex
Bones: humerus, radius, ulna
Joints: humeroradial joint, humeroulnar joint, radioulnar joint (proximal & distal)
T or F
The ulna is larger proximally, while the radius is larger distally
TRUE
The Humeroulnar joint is formed by what specific landmark of the bones?
Formed by the trochlear notch of the ulna
+
The trochlea of the humerus
What is the concave and convex of the humeroulnar joint?
Trochlear notch: concave
Trochlea: convex
How many DOF does the humeroulnar joint have? and what is it?
- DOF: 1 (flexion/extension)
What type of joint id the humeroulnar joint?
Synarthrodial joint; hinge joint
- can be modified as modified hinge joint
What rule is applied to the Humeroulnar joint?
For both flexion and extension
Convex-concave rule: concave on convex
During flexion,
The concavity of the trochlear notch will ___ and ___on the trochlea of the humerus
The concavity of the trochlear notch will ROLL and SLIDE
on the trochlea of the humerus
Which statement id false:
- In open kinematic chain (OKC) motion, sliding and rolling are in the same direction
- In closed kinematic chain (CKC) motion, sliding (posterior) and rolling (anterior) are in different directions
NONE
According to some references, if flexed at ____ (degrees),
there’s no surface contact between the trochlea and
trochlear notch
According to some references, if flexed at 30°-120°,
there’s no surface contact between the trochlea and
trochlear notch
What movement?
The olecranon process (ulna) enters the olecranon fossa (humerus)
Elbow Extension
What happens when the elbow is extended? (what part is lax and taught)
- Anterior part: the flexor muscles, anterior capsule, and
anterior fibers of the MCL are stretched - Posterior part: the extensor muscles and posterior
capsule are slack
What specific bony landmark compose the Humeroradial joint?
Formed by the radial head
+
The capitulum (humerus)
In the humeroradial joint, which is concave and which is convex?
Radial head (fovea): concave
Capitulum: convex
What rule is applied to the Humeroradial joint?
Convex-concave rule: concave on convex
This is a condyloid joint
HUMERORADIAL (HR) JOINT
What movement of the Humeroradial joint;
The rim of the radial head slides in the capitulotrochlear groove which will enter the radial fossa
Flexion
What happens to the humeroradial joint during elbow flexion (which Roll and slide)
- Movement of this is most of the radius on the humerus
- The radial head will ROLL and SLIDE on the capitulum (humerus)
- The radial head will move anteriorly
T or F
Most activities of daily living (ADL) will occur within the arch of 90°-130°
FALSE
Most activities of daily living (ADL) will occur within the
arch of 30°-130°
Normal ROM: of elbow joint (Flex/extend)
Normal ROM: 0-145°
Which is incorrect: HR joint flexion
- OKC: same direction (Posterior)
- CKC: anterior roll, posterior slide
- OKC: same direction (anterior)
Which is incorrect: HR extension
- OKC: same direction (posterior)
- CKC: anterior slide, posterior roll
Both are correct
Aka “pulled elbow”
NURSEMAID’S ELBOW
nursemaid’s elbow is more common to young children who are less than ___ years old
- This is due to the lack of development of the articulation and ligament; less stable
5 years old
Mechanism of injury: of the nursemaid elbow
Mechanism of injury: attraction force within the elbow of the child
The radial head is traumatically pulled out from the attachment (radial fossa)
- This makes the __ ___ to be torn
Nursemaid elbow
Annular ligament is torn
Specific bony composition of the proximal Radioulnar joint
Attachment of the radial notch (ulna)
+
radial head (radius)
What rule is applies to the proximal RU joint?
Concave-convex rule: convex on concave
What is convex and concave in the proximal Ru joint?
- Radial head (rim): convex
- Radial notch: concave
What type of joint is the Proximal RU joint?
Pivot joint
Specific components of the Distal RU joint?
Attachment of the ulnar notch (radius)
+
ulnar head (ulna)
What rule is applied to the Distal RU joint?
Concave-convex rule: concave on convex
Which is convex and concave in the distal RU joint?
- Ulnar head: convex
- Ulnar notch: concave
What movement will the radius will move over the ulna
Pronation
Arthrokinematics of the proximal segment (RU joint) during pronation
OKC:
CKC:
- OKC: the radius will rotate anteriorly on the ulna
- CKC: the radius (convex) is fixed while the ulna (concave) moves, providing the same direction for rotating (anterior)
Arthrokinematics of the distal segment (RU joint) during pronation
OKC:
CKC:
- OKC: the ulnar notch (radius) will roll and slide posteriorly [concave on convex]
- CKC: the ulna (convex) will move against the radius (concave), providing opposite movement; anterior rolling and posterior sliding
According to other references (other than Brunnstrom’s),
the ulna is fixed, however, according to Brunnstrom’s, the
ulna will move posterolaterally
Take note
The movement of the ulna will be ___ during supination
The movement of the ulna will be anteromedial
Arthrokinematics of the proximal segment during supination
OKC:
CKC:
- OKC: the radius will rotate posteriorly
- CKC: the ulna will rotate posteriorly
Arthrokinematics of the distal segment during supination
OKC:
CKC:
- OKC: the ulnar notch (radius) will roll and slide anteriorly
- CKC: the ulna will roll posteriorly and slide anteriorly
What movement will The palmar capsular ligament (anterior hand) will stretch, while the dorsal capsular ligament will be lax
SUPINATION
What movement will the The palmar capsular ligament will be lax, while the dorsal capsular ligament will stretch
PRONATION
LIGAMENTS OF THE ELBOW COMPLEX
MEDIAL/ULNAR COLLATERAL LIGAMENT (MCL)
LATERAL COLLATERAL LIGAMENT COMPLEX (LCL)
ANNULAR LIGAMENT
QUADRATE LIGAMENT
This binds the radius and ulna
INTEROSSEUS MEMBRANE
- Serves as a stable attachment site for several extrinsic muscles of the hand
INTEROSSEUS MEMBRANE
T or F
the Interosseous membrane decreases the surface area for muscle attachment
FALSE
Increases the surface area for muscle attachment
Most of the fibers of the interosseus membrane are called the
CENTRAL BAND
–This has ultimate tensile strength and is twice the thickness of other fibers
Patients with any problem regarding the interosseous membrane should avoid ??
Patients with any problem regarding the interosseous
membrane should avoid compressing and distracting
forces
What force?
The interosseus membrane is stretched (taut) and it
helps with the distribution of force towards the UE
COMPRESSION FORCE
What force?
The interosseus membrane is relaxed (lax/slack)
DISTRACTING FORCE
Stress wherein The forearm moves away from the midline
There’s compression stress on the lateral aspect/compression and distraction stress on the medial aspect of the elbow
VALGUS STRESS
What ligament is stretched during:
VALGUS:
VARUS:
VALGUS: MCL
VARUS: LCL
Normal ROM for elbow flexion:
reffered to as ___ arc
Normal ROM for elbow flexion: 0-145°
Functional arc
Elbow can be flexed actively/passively (based on HR joint), How many degrees for each:
- Active:
- Passive:
Active: 30°-145°
Passive: 150°-160° added
T or F
If the forearm is in a supinated position then it’s flexed, the ROM is less than when the forearm is pronated
FALSE
If the forearm is in a pronated position (or it’s in the process of going to pronation/supination) then it’s flexed, the ROM is less than when the forearm is supinated
If the forearm is supinated THEN flexed, the ROM is?
GREATER
If the forearm is mid-supinated THEN flexed, the ROM is ?
LESSER
T or F
The 30°-130° arch of elbow flexion is the elbow ROM in order to perform all the ADL
TRUE
T or F
The Subclavius and biceps brachii may limit the elbow ROM since these crosses the elbow and shoulder
FALSE
The triceps and biceps brachii may limit the elbow ROM
since these crosses the elbow and shoulder
During shoulder flexion, elbow flexion is LIMITED and
there’ll be tension in the (muscle)
During shoulder flexion, elbow flexion is LIMITED and there’ll be tension in the TRICEPS BRACHII
During shoulder hyperextension, elbow extension is
LIMITED and there’ll be tension in the(muscle)
During shoulder hyperextension, elbow extension is LIMITED and there’ll be tension in the BICEPS BRACHII
- Normal ROM for PRONATION:
- Normal ROM for SUPINATION:
- Functional arch for elbow flexion:
- Normal ROM for PRONATION: 0-75°
- Normal ROM for SUPINATION: 0-85°
- Functional arch for elbow flexion: 30-130°
Functional arch for pronation/supination: __° respectively
50
This is also called the cubitus angle/valgus
CARRYING ANGLE
Which carrying angle is greater male or females?? how many degrees for each?
females 13°-16° GREATER
Male: 11°-14°
If the value is less than normal (<5°), it’s considered as cubitus varus (pathologic deformity) aka?
gunstock deformity
