Elbow Flashcards

Question 1

Q

What is the normal valgus carrying angle of the elbow?

[JAAOS 2018;00:1-10]

Answer

A

11°men

13° women

Question 2

Q

What is normal elbow ROM?

[JAAOS 2018;00:1-10]

Answer

A

Full extension

145° flexion

75^o pronation

85^o supination

Question 3

Q

Describe the distal biceps tendon anatomy and insertion

[Orthopaedic Journal of Sports Medicine June 2015 vol. 3 no. 6]

Answer

A

The tendon externally rotates 90°
* Brings the medial short head fibres anterior and the lateral long head fibres posterior
The tendon inserts with:

Short head fibres distal on the radial tuberosity
- Stronger flexor
Long head fibres proximal
- Stronger supinator

Question 4

Q

What are the reported deficits with nonoperative management of complete distal biceps tears?

Answer

A

Supination

79% endurance [50% loss]
21-55% strength [40% loss]

Flexion

10-40% strength [30% loss]
30% endurance

Question 5

Q

What are the risk factors for distal biceps tendon tear?

Answer

A

Increased BMI

Increased muscle mass = increased tendon load
Obesity = decreased immune response to tendon healing

Smoking

Safran and Graham -7.5x greater risk (limited population n=14)
Kelly et al - odds ratio of 4.47 in patients less than 65
Increases zone of hypovascularity

Anabolic steroid use

Question 6

Q

What are the special tests to evaluate for distal biceps tears?

Answer

A

‘Hook test’

Ask the patient to actively flex the elbow to 90° and to fully supinate the forearm
Examiner uses index finger to hook the lateral edge of the biceps tendon
With an intact or even partially intact biceps tendon, the finger can be inserted 1 cm beneath the tendon
When there is no cordlike structure under which the examiner may hook a finger, the biceps tendon is not in continuity

‘Passive forearm pronation’

Passive forearm pronation from supinated position should result in proximal-to-distal migration of biceps muscle belly
Loss of visible and palpable migration occurs with complete rupture of distal biceps tendon

‘Biceps crease interval’

Measure the distance between the biceps cusp and the antecubital crease
BCI > 6.0 cm or biceps crease ratio greater than 1.2 had a sensitivity of 96% and a diagnostic accuracy of 93% for identifying complete distal biceps tendon ruptures

‘Bicipital aponeurosis flex test’

Patient makes a fist, flexes the wrist, flexes elbow to 75° tensioning the lacertus fibrosus
Palpate location 1 – sharp medial edge of lacertus fibrosus
Palpate location 2 – round lateral edge of distal biceps tendon
Palpate location 3 – valley between lacertus and biceps tendon

‘Biceps squeeze test’
* Patient seated with forearm resting on lap in 60-80° flexion and slight pronation
* Examiner squeezes the biceps brachii with both hands
* Positive test is a lack of forearm supination

Question 7

Q

What is the management of a distal biceps tear?

Answer

A

Operative Indications

Complete tear in medically fit patient unwilling to accept functional losses
Persistent pain following initial conservative management of partial tear

Nonoperative Indications

Low demand patient
Medically unfit for surgery
Partial tear involving <50%

Question 8

Q

What are the surgical considerations for distal biceps tears?

Answer

A

Timing

Acute repair is favoured within 3 weeks of injury
- Delay results in tendon retraction, adhesions, loss of elasticity
- May require more extensile approaches and dissection leading to complications
- Intact lacertus fibrosus may limit retraction and permit delay
No consensus on definition of chronic
- ?>3 weeks, ?>2 months, ?>4 months
- Chronic injuries limit ability to repair primarily
- Techniques include repair in high flexion (>70°) and tendon augmentation with graft
  1. Anatomic vs. Non-anatomic repair
3 components of anatomic distal biceps repair:
- Replicate the external rotation of the tendon
- Restore the native short and and long head attachment sites
- Preserve the radial tuberosity anatomy
Nonanatomic repairs result in:
- Failure to recreate the tendon external rotation
- Create attachment site that is more anterior than the native footprint
- Reduce the height of the radial tubersity by creating a trough
Clinical importance?
- Anatomic repairs have been shown to have improved supination strength
- Nonanatomic repairs cause premature unwinding of the distal tendon and the loss of the cam effect of the radial tuberosity
  1. Single vs. Double Incision
Single-Incision Technique
- Longitudinal, transverse or S-shaped incision (extensile)
- Identify and protect the LABC nerve
- Interval:
  - Proximal – brachioradialis and brachialis
  - Distal – brachioradialis and pronator teres
- Leash of radial recurrent vessels may need ligating
- Forearm held in supination to protect the PIN and bring the radial tuberosity into view
Double-Incision Technique
- ‘Modified Boyd-Anderson approach’
- Utilizes the same anterior incision as the single-incision
- Radial tuberosity is identified and a curved kelly is passed along its medial border between the radius and ulna
- With the arm in full pronation to protect the PIN the posterior incision is made over the tip of the kelly
- The ECU is split exposing the radial tuberosity
  1. Distal biceps fixation technique
Options include:
- Bone tunnel fixation
  - Sutures tied over bone bridge
- Suture anchor
- Interference screw
- Cortical button
  - Extramedullary or Intramedullary
- Hybrid (button/interference screw)
Greatest pullout strength = cortical button
- Endobutton> suture anchors/repairs=Trans osseus >interference screw
  1. Postoperative management
Splint elbow in 90° flexion and supination for 1-2 weeks
Once splint discontinued start ROM
Forearm rotation emphasized
Terminal elbow extension avoided for first 6 weeks
Resistance training started 8 weeks post surgery
Heavy activities resumed 3-5 months post surgery

Question 9

Q

What are the complication rates of single vs. double incision techniques for distal biceps tendon repair?

[The Orthopaedic Journal of Sports Medicine Oct 2016 vol. 4 no. 10]

Answer

A

More common in Single Incision

Neuropraxia (9.9% vs. 2.2%)
PIN palsy (1.7% vs. 0.2%)
Rerupture (2.1% vs. 0.6%)
Total complications (28.2% vs. 20.9%)
2. More common in Double Incision
HO (7.2% vs. 3.2%)
Synostosis (2.2% vs. 0%)

Question 10

Q

What are the potential causes of a stiff elbow?

[Curr Rev Musculoskelet Med (2016) 9:190–198]

Answer

A

Intrinsic causes

Joint incongruity
Cartilage loss
Intra-articular malunion
- Particularly the ulnohumeral joint
Arthritis
Loose bodies
2. Extrinsic causes
Burns
Muscle contracture
Heterotopic bone
Joint capsule contracture
Ligament contracture
- Posterior band of the MCL
Extra-articular malunions
- Loss of the normal anterior translation of the capitellum and trochlea relative to the anterior humeral shaft
Nonunion
3. Other
Inflammatory arthritis
Hemophilia
Infection

Question 11

Q

What is the functional range of motion of the elbow?

[J Am Acad Orthop Surg 2011;19: 265-274]

Answer

A

100° flexion-extension arc (30°-130°)

100° pronation-supination arc (50°-50°)

Question 12

Q

What range of motion loss is better tolerated?

[JAAOS 2015;23:328-338]

Answer

A

Extension loss is better tolerated than flexion loss

Question 13

Q

Treatment options for the stiff elbow

[Curr Rev Musculoskelet Med (2016) 9:190–198]

Answer

A

Nonoperative (consider within first 6 months)

Therapy
Splinting
- Static progressive splinting
  - Stepwise increase in the joint angle
  - Force applied to tissues decreases as the tissues stretches
- Dynamic splinting
  - Consistent force is applied to the tissues as they stretch
Manipulation under anaesthesia
2. Operative
Open release
- Lateral approach (lateral column procedure)
- Medial approach (medial column procedure)
- Anterior approach (rare)
Arthroscopic release
Interpositional arthroplasty
- Alternative to arthroplasty in younger patients
Total elbow arthroplasty
Partial elbow arthroplasty
Arthrodesis

Question 14

Q

What are the indications for elbow release surgery?

[JAAOS 2015;23:328-338]

Answer

A

Stiffness that limits ADLs

Nonoperative treatment should attempted for at least 3-4 months
Tissue equilibrium should be reached
- No swelling or erythema

Question 15

Q

What are contraindications for elbow release surgery?

[JAAOS 2015;23:328-338]

Answer

A

Closed head injury with neurologic dysfunction
Noncompliant patient
Joint space narrowing (relative)
Incongruous elbow (relative)

May require two-stage procedure
- 1st stage
  - Joint reduction and ligament repair/reconstruction
- 2nd stage
  - Elbow release after tissue equilibrium reached

Pain in midarc (relative)
Inadequate soft tissue envelope (relative)
* Consider plastics consult for flap coverage

Question 16

Q

What structures need to be addressed to improve flexion and extension in a stiff elbow?

Answer

A

Flexion

Posterior joint capsule
Triceps adhesion
Coronoid process osteophytes
Coronoid and radial fossa
Posterior band of the MCL
2. Extension
Anterior joint capsule
Brachialis adhesion
Olecranon osteophyte
Olecranon fossa
3. Other
Loose body
Hardware
Heterotopic ossification

Question 17

Q

What are the advantages and disadvantages of an open lateral approach for management of a stiff elbow?

[JAAOS 2015;23:328-338]

Answer

A

Advantages
* Simple, access to all 3 articulations
Disadvantages
* No access to ulnar nerve

Question 18

Q

What are the advantages and disadvantages of an open medial approach for management of a stiff elbow?

[JAAOS 2015;23:328-338]

Answer

A

Advantages

Direct ulnar nerve access
More cosmetic scar
Direct release of posteromedial capsule

Disadvantages

No lateral joint access
Proximity to MABCN
Potentially more muscle morbidity with elevation of flexor-pronator mass

Question 19

Q

Describe the open medial approach for elbow release?

[JAAOS 2015;23:328-338]

Answer

A

Incision

6-8cm proximal to medial epicondyle and 1cm posterior to medial intermuscular septum
Extended distally curving anteriorly 5-6cm
Protect the MABCN

Ulnar nerve release
* Release from septum to FCU
Expose posterior elbow

Elevate triceps off medial intermuscular septum, distal humerus and posterior joint capsule
Perform posterior capsulectomy
Debride the joint
- Elevate or excise the posterior fat pad
- Remove fibrous tissue
- Remove loose bodies
- Olecranon fossa deepening
- Olecranon tip excision
  1. Release the posterior bundle of the MCL
  2. Expose the anterior elbow
Elevate the brachialis and anterior 2/3 of the flexor-pronator mass off the distal humerus and anterior capsule
Perform anterior capsulectomy
Debride the joint
- Remove fibrous tissue
- Remove loose bodies
- Coronoid and radial fossa deepening
- Coronoid tip excision
  1. Brachialis and triceps release
Bluntly elevate muscles off humerus proximally
Do not perform tendon lengthening

Close

Repair the flexor pronator mass
Transpose ulnar nerve anteriorly
Place a drain
Apply soft dressing

Question 20

Q

Describe the open lateral approach for elbow release?

[JAAOS 2015;23:328-338]

Answer

A

Incision
* 8-12cm from lateral supracondylar ridge to the interval between anconeus and ECU (Kocher)
Expose posterior joint

Elevate triceps off posterior humerus and joint capsule
Perform posterior capsulectomy
Debride posterior joint
- Elevate or excise the posterior fat pad
- Remove fibrous tissue
- Remove loose bodies
- Olecranon fossa deepening
- Olecranon tip excision
  1. Access the lateral gutter
[Posterior radiocapitellar joint – “soft spot”]
Reflect anconeus posterior with triceps
Incise capsule posterior and proximal to radial head
Debride lateral gutter
- Osteophytes or loose bodies behind capitellum
- Synovitis
  1. Expose anterior joint
Interval between ECRL and ECRB distally
Elevate brachialis and ECRL off the anterior joint capsule and distal humerus
Perform anterior capsulectomy
Debride the anterior joint
- Remove fibrous tissue
- Remove loose bodies
- Coronoid and radial fossa deepening
- Coronoid tip excision
Debride the PRUJ and radiocapitellar joint if supination/pronation limited
- Bony spurs
- Release anterior capsule and annular ligament
  1. Close
Repair the Y-shaped fascial split
- Intervals between anconeus and ECU/ECRL and ECRB
Place a drain
Apply a soft dressing

Question 21

Q

What is the postoperative management following open surgical elbow release for stiff elbow?

[JAAOS 2015;23:328-338]

Answer

A

Immediate CPM
* Continue for 1 month
Formal therapy start POD1
Early static progressive elbow splinting

Wear for 30mins 3 times per day
Alternate flexion and extension
Continue for several months

Indomethacin x3/52
Single-fraction radiation therapy in a dose of 700 cGy within the first 48 hours of surgery may be used in selected cases in which extensive heterotopic bone has been removed.

Question 22

Q

Post open surgical release of a stiff elbow, how long is the final ROM maintained for?

[JAAOS 2015;23:328-338]

Answer

A

ROM achieved at 1 year can be expected to be maintained for up to 10 years

Question 23

Q

What complications are associated with open elbow release for stiff elbow?

[JAAOS 2015;23:328-338]

Answer

A

Ulnar neuritis
Wound complications
Loss of ROM
HO
Pain CRPS
Triceps insufficiency
Instability

Question 24

Q

What are the contraindications for arthroscopic elbow release?

[JAAOS 2011;19:265-274]

Answer

A

Extensive HO
Severe elbow contractures

Extra-articular adhesions
Muscle adhesions
Difficulty insufflating joint

Loss of pronation/supination
Prior ulnar nerve translocation (relative)
Severe articular damage or incongruity

Question 25

Q

When should ulnar nerve transposition be considered when releasing a stiff elbow?

[JAAOS 2011;19:265-274]

Answer

A

Preoperative elbow flexion ≤90 degrees
Preoperative ulnar nerve symptoms

Question 26

Q

What is the Outerbridge-Kashiwagi ulnohumeral arthroplasty?

[JAAOS 2002;10:106-116]

Answer

A

Indicated for stiffness due to primary osteoarthritis
* Allows for debridement of the anterior and posterior compartments with less soft tissue dissection
Technique

Posterior midline incision
Triceps split
Posterior capsulectomy
Olecranon tip excision
Olecranon fossa fenestration (burr or trephine)
Coronoid and radial head debridement and loose body removal

Question 27

Q

What are the static and dynamic stabilizers of the elbow?

[AAOS comprehensive review, 2014]

Answer

A

Primary static constraints

Ulnohumeral articulation
Anterior bundle of MCL
LCL complex

Secondary static restraints

Radiocapitellar articulation
Common flexor origin
Common extensor origin
Capsule
3. Dynamic constraints
Triceps
Anconeus
Brachialis

Question 28

Q

What is the anatomy and function of MCL of the elbow?

[World J Orthop 2018 June 18; 9(6): 78-84]

Answer

A

Function

Primary static stabilizer
- Resists valgus
Anterior band tight in extension
Posterior band tight in flexion

Origin

Anterior, inferior and lateral aspect of the medial epicondyle
Posterior to the elbow axis of rotation

Insertion

Sublime tubercle and UCL ridge
- UCL ridge extends from the sublime tubercle distally as the ligament tapers out [JAAOS 2014;22:315-325]
- Recently shown to have a longer and distally tapered insertion
  - Extending beyond the sublime tubercle

Question 29

Q

What is the anatomy of the LUCL of the elbow?

[Okajimas Folia Anat. Jpn. 2017; 93(4)147]

Answer

A

Function

Primary static stabilizer
- Resists varus
Resists posterolateral rotatory instability

Origin
* Center of capitellum, anterior to lateral epicondyle
Course

Attached to the annular ligament
- Located at the 8 to 9 o’clock position of the radial head
Acts as a hammock to the radial head

Insertion

From lesser sigmoid notch to the supinator crest
Proximal edge is 7mm distal to the proximal radial head

Question 30

Q

What is the progression of soft tissue disruption around the elbow at the time of dislocations?

[Shoulder & Elbow 2017, 9(3) 195–204][AAOS comprehensive review, 2014]

Answer

A

Controversial, some believe the MCL is always disrupted
Circle of Horii

Stage I
- Disruption of the LUCL
  - Results in posterolateral rotatory subluxation
Stage II
- Disruption of other lateral ligamentous structures + anterior and posterior capsule
  - Incomplete posterolateral dislocation
Stage III
- Disruption of the MCL
  - Complete posterior dislocation
- Stage IIIA - Posterior band of MCL
- Stage IIIB - Entire MCL
- Stage IIIC - distal humerus stripped of soft tissue
  - Flexor-pronator origin disrupted
    3. Injury ladder for posterolateral simple elbow dislocations
Injury starts medial and progresses ‘up the ladder’
Medial ligament tear → CFO avulsion → anterior capsule tear → lateral ligament tear → common extensor tendon avulsion
Goal of surgery is to ‘bring the patient down the ladder’

Question 31

Q

What is the management of simple elbow dislocation?

Answer

A

Closed reduction

Technique
- Supinate the forearm
- Correct medial/lateral displacement
- Apply inline traction allowing the coronoid to clear the trochlea
- Flexion with pressure to the olecranon
Assess stability
- Determine stable arc of motion
- Determine if more stable in pronation, neutral or supination
- Splint arm in 90° with forearm in position of stability
Postreduction radiographs
- Ensure concentric reduction and no fractures
  1. Nonoperative
Post reduction splint for 5-7 days
Initiate gravity-assisted overhead motion protocol [J Hand Surg Am. 2015;40(3):515e519]
- Patient is supine with the shoulder flexed, adducted and in neutral external rotation position
  - Eliminates gravitational varus and distraction forces
  - In this position elbow flexion/extension and pronation/supination are performed
    - Limits of motion are dictated by patient
    - Arm is splinted in 90^o when not performing exercises
- Overhead motion performed for 3-4 weeks
- Upright motion started at 3-4 weeks
- At 6 weeks progress ROM, strengthening, ADLs
  1. Operative [AAOS comprehensive review,2014]
Indications
- Incongruent joint postreduction
- Stability not maintained by closed means
- Open
- Neurovascular injuries requiring surgery
Technique
- Repair LUCL/common extensor origin
- +/- MCL repair
- +/- hinged ex-fix

Question 32

Q

What is the definition of a complex elbow dislocation?

[JAAOS 2015;23:297-306]

Answer

A

Elbow dislocation with associated fracture

Question 33

Q

Of elbow dislocations, what percentage are complex?

[JAAOS 2015;23:297-306]

Question 34

Q

What are the 3 injury patterns and mechanisms of complex elbow dislocations?

[JAAOS 2015;23:297-306]

Answer

A

Axial loading
Valgus posterolateral rotatory
Varus posteromedial rotatory

Question 35

Q

What is the most common injury pattern in complex elbow dislocations?

[JAAOS 2015;23:297-306]

Answer

A

Valgus posterolateral rotatory injury (80%)

Question 36

Q

What is the mechanism of an axial loading injury (in context of complex elbow dislocation)?

[JAAOS 2015;23:297-306]

Answer

A

The dorsal forearm sustains a direct blow resulting in the distal humerus impacting the greater sigmoid notch of the ulna

“Transolecranon fracture dislocation”
“Pilon fracture of the elbow”

Question 37

Q

What effect does a transolecranon fracture dislocation have on the PRUJ, MCL and LCL?

[JAAOS 2015;23:297-306]

Answer

A

PRUJ remains intact
LCL and MCL complexes remain attached to the distal fragment

Question 38

Q

What construct is used for ORIF of a transolecranon fracture dislocation?

[JAAOS 2015;23:297-306]

Answer

A

Precontoured olecranon plate

Question 39

Q

What is the postoperative protocol following ORIF of a transolecranon fracture dislocation?

[JAAOS 2015;23:297-306]

Answer

A

Splint 5-7 days
Progressive AROM
Strengthening at 6-8 weeks

Question 40

Q

What is the mechanism of a valgus posterolateral rotatory injury?

[JAAOS 2015;23:297-306]

Answer

A

Axial loading combined with valgus and supination at the elbow

Question 41

Q

What is the progression of injured structures in a valgus posterolateral rotatory injury?

[JAAOS 2015;23:297-306]

Answer

A

Avulsion of LUCL from lateral epicondyle
Radial head fracture and subluxation inferior to capitelum
Tip of coronoid fracture as a result of subluxation of greater sigmoid notch relative to distal humerus
MCL disruption

Question 42

Q

What is the immediate emergency department management of a posterolateral rotatory injury?

[JAAOS 2015;23:297-306]

Answer

A

Procedural sedation
Closed reduction
* Traction with elbow in extension to allow coronoid to clear distal humerus followed by flexion
Assess stability

With the forearm in pronation bring the elbow back to extension to determine at which degree of flexion the elbow subluxates
If >30^o= elbow is unstable

Assess the DRUJ to rule out Essex-Lopresti injury
Splint the elbow in 90° flexion with forearm in pronation
Postreduction xrays and CT scan

Question 43

Q

What are the indications for nonoperative management of a posterolateral rotatory injury?

[JAAOS 2015;23:297-306] [JAAOS 2009;17:137-151][Curr Rev Musculoskelet Med. 2016 Jun; 9(2): 185–189.]

Answer

A

Small, minimally displaced radial head fracture with no mechanical block to supination/prontation
Small coronoid tip fracture (Regan-Morrey type 1 or 2)
Stable during postreduction testing
* Elbow should extend to 30° before becoming unstable
Concentric reduction of the ulnotrochlear and radiocapitellar joints

Question 44

Q

What is the general surgical management for posterolateral rotatory injury (terrible triad)?

[JAAOS 2015;23:297-306]

Answer

A

Fixation of the coronoid
Fixation or replacement of the radial head
Repair of the LUCL complex
Possible repair of the MCL
External fixator if the elbow remains unstable

Question 45

Q

What approach is used for management of terrible triad injuries?

[JAAOS 2015;23:297-306]

Answer

A

Lateral approach +/- medial approach
Posterior incision with lateral +/- medial flaps

Question 46

Q

What are the intervals for lateral approach to the elbow?

[JAAOS 2015;23:297-306] [JAAOS 2009;17:137-151]

Answer

A

EDC split
* Aim to be at the equator of the radial head, slightly anterior to the Kocher interval
Kocher interval
* Anconeus and ECU
If the common extensor origin is avulsed use the plane created by the injury

Question 47

Q

When using a lateral approach for a terrible triad, when is a supplemental medial approach necessary?

[JAAOS 2015;23:297-306]

Answer

A

If residual instability is present after fixation of the coronoid, radial head and LUCL
If the coronoid fracture was not adequately addressed from the lateral side

Question 48

Q

What intervals are used for the medial approaches to the elbow?

Answer

A

Hotchkiss “over the top”
* Interval between FCU and palmaris longus
FCU split
Floor of the cubital tunnel between the two heads of the FCU

Insitu release of the ulnar nerve
Split FCU in line with fibres to expose the sublime tubercle

Question 49

Q

What O’Driscoll type of coronoid fracture is seen in terrible triad injuries and what are the options for fixation?

[JAAOS 2015;23:297-306] [JAAOS 2009;17:137-151]

Answer

A

O’Driscoll type 1 (tip)

Suture lasso technique
- # 2 nonabsorbable suture passed around coronoid and anterior capsule
- Suture passed through 2 drill holes
  - Use ACL guide
- Tie over the posterior ulna with the elbow reduced and held in flexion after radial head fixed/replaced and LUCL repaired
Small AP lag screws +/- minifrag plate supplementation
Small cannulated PA lag screws

Question 50

Q

What are the surgical options for the radial head fracture in a terrible triad injury?

[JAAOS 2009;17:137-151]

Answer

A

Fragment excision if:

<25% of head involved
Fragments are too small or osteoporotic to fix
Fragments do not articulate with the PRUJ

ORIF:

Countersunk traditional screws
Headless compression screws
Plates

Radial head replacement if:

Radial head is communited
Radial neck is comminuted
Poor bone quality

Question 51

Q

When performing radial head replacement how do you assess height of the radial head in relation to the ulna?

[JAAOS 2014;22:633-642] [JBJS 2010;92:250-257]

Answer

A

Align the proximal surface of the implant with the proximal portion of the lesser sigmoid notch
Assess for gapping of the lateral ulnohumeral joint space
* Direct visualization more reliable than fluoro
Assess congruency of the medial ulnohumeral joint space (fluoro)
Assess radiocapitellar gap in flexion and extension
* Should be equal
Proximal aspect of the implant should be at the lateral edge of the coronoid

Question 52

Q

How can the lateral ulnohumeral joint be visualized to assess gapping when doing a radial head replacement?

[JBJS 2010;92:250-257]

Answer

A

Release some extensor origin from the lateral supracondylar ridge
Use an angled dental mirror to peer over the radial head
Posterior through the Boyd interval
* Anconeus and supinator released off ulna exposing posterolateral capsule

Question 53

Q

When performing radial head replacement how do you size the radial head diameter?

[Rockwood and Green 8th ed. 2015]

Answer

A

Reconstruct the fragments of the head on the back table
Optimal diameter is the minor diameter of the native elliptical head
* Usually 2mm less than the maximum diameter
When in between sizes choose the smaller diameter

Question 54

Q

What are the consequences of overstuffing the radiocapitellar joint when performing a radial head arthroplasty?

[JBJS 2010;92:250-257]

Answer

A

Decreased elbow flexion
Capitellar erosion
Pain

4. Early posttraumatic arthritis

Question 55

Q

Where does the LCL avulsion occur from in a terrible triad injury?

[JAAOS 2015;23:297-306]

Answer

A

Almost always from the humeral attachment

Question 56

Q

What are the repair options for LCL repair?

[JAAOS 2015;23:297-306]

Answer

A

2 nonabsorbable suture placed through drill holes in the distal aspect of the lateral epicondyle

Or suture anchors placed at the avulsion site

Question 57

Q

What is the “hanging arm test” (during terrible triad surgery)?

[JAAOS 2015;23:297-306]

Answer

A

Perform after coronoid, radial head and LCL repair
Humerus is placed on a stack of towels with the elbow in full extension and forearm in supination which allows gravity to produce a dislocating force, confirm a concentric reduction with fluoroscopy
If unstable (subluxation) repair the MCL +/- coronoid fixation (if inadequately addressed) via medial approach

Question 58

Q

What are the indications for MCL repair in a terrible triad injury?

[JAAOS 2009;17:137-151] [JAAOS 2015;23:297-306]

Answer

A

Instability following coronoid, radial head and LCL repair determined by:

Positive hanging arm test
Instability with ROM in supination, pronation and neutral rotation
- If the elbow remains congruous from approximately 30° to full flexion in one or more positions of forearm rotation, repair of the MCL is not necessary

Question 59

Q

Where does the MCL avulsion occur in a terrible triad injury?

[JAAOS 2015;23:297-306]

Answer

A

Variable

Humerus, intrasubstance or sublime tubercle

Question 60

Q

What are the repair options for MCL repair in a terrible triad injury?

[JAAOS 2015;23:297-306]

Answer

A

Sublime tubercle avuslion – drill holes in ulna at sublime tubercle
Humeral avulsion – drill holes in distal anterior medial epicondyle

Question 61

Q

What are the indications for external fixation after surgical management of a terrible triad injury?

[JAAOS 2015;23:297-306]

Answer

A

Residual instability after lateral and medial repair
Static or hinged acceptable

Question 62

Q

What complications are associated with terrible triad injuries?

[JAAOS 2009;17:137-151]

Answer

A

Instability
Malunion
Nonunion
Stiffness
Heterotopic ossification
Infection
Ulnar neuropathy

Question 63

Q

What is the postoperative protocol following surgical repair of terrible triad injury?

[JAAOS 2015;23:297-306]

Answer

A

Immobilize the elbow in splint

Pure lateral repair – splint in pronation
Lateral and medial repair – splint in neutral

Remove splint in one week
Apply hinged elbow brace with terminal extension limited to 30° for 4 weeks
AROM before PROM
* Muscle contraction provides stability
Resistive exercises starting at 6-8 weeks

Question 64

Q

What is the mechanism of a varus posteromedial injury?

[JAAOS 2015;23:297-306]

Answer

A

Axial load combined with varus and pronation at the elbow

Answer 64

A

LCL avulsion as a result of the varus force
Anteromedial coronoid facet fracture as the trochlea impacts the facet
Coronoid dislocation posterior to the trochlea

Answer 65

A

Type II

Subtype A – anteromedial rim
Subtype B – anteromedial rim + tip
Subtype C – anteromedial rim + sublime tubercle

***As per 2018 Canadian Study, Type IIB most common, followed by Type IIC [JOT 2018, 32(12), e469–e474]

***Note: increasing instability occurs with increasing subtypes

Answer 66

A

AP
* Narrowed medial joint space and gapping of the radiocapitellar space
Lateral
* “Double crescent” sign indicating a depressed anteromedial facet fracture

Answer 67

A

Anteromedial facet of coronoid fixation
LCL repair

Answer 68

A

FCU split*
Hotchkiss “over the top”
Floor of cubital tunnel after ulnar nerve transposition
* Elevate the FCU off the ulna

Answer 69

A

Buttress plate and screws
Lasso technique for small fragments

Answer 70

A

Splint in 90° of flexion and neutral forearm rotation
At 1 week begin AROM in hinged elbow brace
* Block terminal extension at 30° if concerned about bony fixation for 4 weeks
At 6-8 weeks begin resistance exercises

Answer 71

A

Posterior midline incision
AMF subtype 1
* LCL repair alone
AMF subtype 2+3

LCL repair and buttress plate
- T-plate, miniplate or precontoured plate

If elbow unstable after LCL and AMF fixation assess for MCL injury

Answer 72

A

Minimally displaced or undisplaced smaller subtype 1 and 2 fractures
* Especially those ≤5 mm
Concentric elbow joint
Stable range of motion to a minimum of 30° of extension

Answer 73

A

Fix the coronoid fracture
Fix or replace the radial head
Repair the LCL
Assess elbow stability within 30-130^oof flexion-extension with the forearm in full pronation
If elbow remains unstable consider fixing the MCL
Failing this, apply a hinged external fixator to maintain concentric reduction and allow for early motion

Answer 74

A

Elbow dislocation that has remained unreduced for >2 weeks

Note that chronic instability differs from recurrent instability of the elbow

Answer 75

A

Triceps contracture
Collateral ligament contracture
Anterior and posterior capsule contracture
Extensive intra-articular fibrosis
Ulnar neuritis and fractures may be present

***NOTE: HO is present 75% of the time but produces mechanical block to motion in <5%

Answer 76

A

AP, lateral and oblique xrays
CT scan
Be prepared to repair or reconstruct ligaments
* Have allograft available
External fixation

Hinged preferred over static
Transarticular pinning is another option

Be prepared for salvage options in event of extensive articular damage

Answer 77

A

Age >65

Total elbow arthroplasty

Age <65

Interposition arthroplasty
Distraction arthroplasty
Arthrodesis

Answer 78

A

Dislocation of ≥3 months
<100° of intraoperative elbow flexion
>5 cm of overlap between the humerus and the olecranon on AP radiographs of the elbow

Answer 79

A

Posterior midline incision with large full thickness fasciocutaneous flaps
Identify and release the ulnar nerve
Medial and lateral paratricipital approach utilized with lateral extension into the Kocher interval
Perform releases and debridement

Mobilize distal triceps off posterior humerus
Release common extensor origin and LCL off the lateral epicondyle
Release anterior and posterior capsule
Release MCL off the medial epicondyle
Debride fibrotic tissue from olecranon and coronoid fossa
5. Reduce the elbow and take it through ROM
Excise HO if limits ROM
If <100° perform a triceps lengthening in V-Y fashion

Stabilize with hinged external fixator

Two 5mm pins in the humerus and two 4mm in the ulna
The axis guidepin is inserted lateral to medial starting just distal to the lateral epicondyle and exiting just anterior and distal to the medial epicondyle
The hinged external fixator is constructed around the axis guidepin then the axis pin is removed
7. MCL and LCL are repaired with their associated common flexor/extensor
8. Ulnar nerve transposition is performed if patient had ulnar nerve symptoms preoperative or intraop flexion places the nerve under tension
9. Hinged ex-fix is left in place for 6 weeks

Answer 80

A

Valgus = MCL
Posterolateral rotatory instability (PLRI) = LUCL
* Deficiencies in coronoid, radial head, and MCL can further destabilize
Posteromedial rotatory instability (PMRI) = anteromedial coronoid facet fracture and LUCL

Answer 81

A

Terminal pain
* Due to osteophyte and/or capsular contracture
Pain throughout arc of motion
* Due to advanced degenerative changes
Rest pain
* Due to infection, inflammatory arthritis, CRPS, etc

Answer 82

A

Arthroscopic debridement and capsular release

Contraindications
- Severe contracture
- Arthrofibrosis
- Ulnar nerve transposition
- Previous surgery

Open procedures

Outerbridge-Kashiwagi procedure
Column procedure
- Limited lateral approach along lateral supracondylar osseous ridge
- Anteriorly, release FCR and brachioradialis
- Posteriorly, elevate triceps from distal humerus and capsule
- Resect anterior/posterior capulse and osteophytes

Answer 83

A

Isolated radiocapitellar disease

Radial head excision
Radiocapitellar interpositional arthroplasty
- Radial head excision
- Anconeus passed below the LCL and interposed in the radiocapitellar articulation
Partial joint arthroplasty
- Radial head arthroplasty
- Radiocapitellar arthroplasty
  1. Isolated distal humerus disease
Distal humerus hemiarthroplasty
3. Diffuse elbow disease
Interpositional arthroplasty
- Autograft (eg. fascia lata, cutis)
- Allograft (eg. achilles, dermis)
TEA

Answer 84

A

Rheumatoid arthritis
Primary arthritis
Post-traumatic arthritis
Instability
Distal humeral nonunion
Distal humeral fracture
* Nearly 70% of TEA used are for trauma

Answer 85

A

Fracture fixation precludes ORIF secure enough to allow early functional recovery
* IE. Comminution, articular involvement, poor bone quality
Fracture in the setting of pre-existing arthritis, instability, nonunion, malunion

Answer 86

A

Infection (Absolute Contraindication)
Severe neurological injury (Absolute)
Poor soft tissue coverage (Absolute)
Fractures amenable to ORIF (Absolute)
Physiologically young and high demand
Cognitive impairment
* Unable to comply with postoperative restrictions

Answer 87

A

Advantages

More predictable return to function
- Does not rely on bone healing
- Preserves extensor mechanism
Avoids complications of nonunion, malunion, posttraumatic arthritis

Disadvantages

Complications more devastating than ORIF complications
- Osteolysis, implant loosening, implant failure, periprosthetic infection, and periprosthetic fracture
- Others - superficial infection, elbow stiffness, wound healing or skin breakdown problems, ulnar neuropathy, and bearing wear

Answer 88

A

Infection
Lack of elbow flexion (neurogenic dysfunction)
* Lack of elbow extension is not a contraindication as it can be achieved with gravity
Poor skin quality (relative)

Answer 89

A

Unlinked/unconstrained/joint resurfacing
* Collateral ligaments are preserved
Semi-constrained/linked
* Articulation allows a few degrees (6-8°) of varus/valgus and rotational laxity
* Stability does not rely on radial head or collateral ligaments
Constrained

Rigid articulation
Not a conventional design

Answer 90

A

10lbs limit

Answer 91

A

Resists the posteriorly directed and rotational forces across the elbow

Answer 92

A

Triceps-splitting

Longitudinal split of the triceps in continuity with the forearm fascia over the dorsal ulna
Alternative - V-shaped turndown of triceps with olecranon insertion left intact

Triceps-reflecting (Bryan-Morrey)
* Triceps and anconeus are reflected from medial to lateral in continuity off the olecranon
- Requires re-attachment of the triceps to the olecranon through cruciate tunnels
Triceps-sparing
* Medial and lateral triceps are mobilized off the supracondylar columns
* Common extensor and flexor pronator mass are released
* Distal humerus can be delivered through the lateral window and the ulna through the medial window

Answer 93

A

Failure requiring revision

Infection
Aseptic loosening
Fracture
Component failure
Instability

Failure requiring additional surgery

Nerve entrapment (usually ulnar)
Ankylosis
Triceps insufficiency

Complications causing morbidity

Wound infections
Paraesthesias
Fractures

Answer 94

A

Rate of infection = 3-8%
Most common and most virulent organism = Staphylococcus epidermidis
If organism not Staph epidermidis = 1 or 2-stage revision
If organism is Staph epidermidis = 2-stage revision or resection arthroplasty

Answer 95

A

Bushing wear
Presents with pain, crepitus and/or squeaking
Managed with bushing exchange

Answer 96

A

Mayo classification

Type I
- Fracture of the humeral condyles or olecranon
Type II
- Fracture along the length of the humeral or ulnar stem
- Type II1
  - Stable component
- Type II2
  - Unstable component
  - Adequate bone stock
- Type II3
  - Unstable component
  - Inadequate bone stock
Type III
- Fracture beyond the tip of the humeral or ulnar stem

Answer 97

A

Fractures that result in loose components or compromise the function

Type I
- Humeral condyles = ORIF or excision if the fixation is tenuous
  - Excision requires releasing the common extensors or flexor-pronator with insertion into the triceps fascia
- Olecranon = tension band
Type II
- Type II1 (stable component)
  - ORIF with anterior and posterior strut allografts or posterior plate
- Type II2 (unstable component, good bone)
  - Revision of implant with strut allograft or plate and screw augmentation
- Type II3 (unstable component, poor bone)
  - Revision with strut allograft or APC
Type III
- Functional brace
- ORIF if functional brace fails

Answer 98

A

Elbow extension with anterior splint to take pressure off posterior incision

Answer 99

A

Debridement for septic elbow
Synovectomy for inflammatory arthritis
Debridement for OA
Loose body removal
Contracture release
OCD
Selected fractures and instability
Tennis elbow

Answer 100

A

Prior elbow surgery (relative)
Prior ulnar nerve transposition (relative)
* Subcutaneous transposition not contraindicated if ulnar nerve identified
* Intramuscular and submuscular are generally considered absolute contraindications

Answer 101

A

Standard portals

Anterolateral
- Just anterior to radiocapitellar joint
  - 3cm distal and 1cm anterior to lateral epicondyle
- Smallest margin of safety from neurovascular structures
  - More proximal placement increases safety
- At risk = radial n. and LABCN
Anteromedial
- 1-2cm anterior and distal to medial epicondyle
  - Traverses flexor-pronator mass
- High margin of safety from neurovascular structures
- At risk = MABCN
Posterolateral
- Lateral border of the triceps at a point midway between olecranon and lateral epicondyle
Direct posterior
- 2-3cm proximal to tip of olecranon
  1. Accessory portals
Direct lateral (‘soft spot portal’)
- Centered between the tip of olecranon, lateral epicondyle and radial head
Distal ulnar portal
- 3-4cm distal to the radiocapitellar joint
Accessory anterior retraction portals
- Proximal Anteromedial
  - 2cm proximal to medial epicondyle just anterior to supracondylar ridge and intermuscular septum
- Proximal Anterolateral
  - 2cm proximal to lateral epicondyle just anterior to supracondylar ridge

Answer 102

A

Lateral decubitus

Axillary roll beneath bottom arm
Affected arm on arm holder

Tourniquet applied and inflated to 200-250mmHg
Joint is insufflated with 25-30mL of saline from direct lateral portal site

Answer 103

A

Persistent drainage/fistula
HO
Nerve injury – ulnar nerve most common

Answer 104

A

Articular branch to the elbow arising just proximal to the cubital tunnel

Answer 105

A

Motor branch to FCU

Order of supply:

FCU
FDP ring & small
Abductor digiti minimi
Opponens digiti minimi
Flexor digiti minimi
Lumbricals 3 & 4
Flexor pollicis brevis (deep head)
Adductor Pollicis
Interossei
- 1st dorsal interosseous is last to be innervated

Answer 106

A

Medial intermuscular septum
Arcade of Struthers

Discrete fascial band about 1.5-2cm in width
Located 8-10 cm proximal to the medial epicondyle

Triceps fascia
Osborne ligament (most common site)

Roof of cubital tunnel
Consists of aponeurosis of the FCU that spans the medial epicondyle and olecranon and connects the ulnar and humeral heads of the FCU

Medial epicondyle
FCU

Deep fascia
Between two heads

FDS/FDP fascia
Anconeus epitrochlearis
* Anomalous muscle which arises from medial border of olecranon & adjacent triceps & inserts into the medial epicondyle
Canal of Guyon

Answer 107

A

Motor

FCU
Ulnar half of FDP
All intrinsics except lateral 2 lumbricals and thenar muscles
- Except deep head of FPB

Sensory

Elbow joint
Ulnar palm and dorsum of hand including small finger and ulnar half of ring finger
Branches:
- Articular branch of the elbow
- Dorsal cutaneous branch
- Palmar cutaneous branch
  - Only present in 58% of people
- Terminal superficial branch

Answer 108

A

Compression/traction of the ulnar nerve at the elbow
Characterized by:

Numbness and paraesthesia of:
- Small finger
- Ulnar half of the ring finger
- Ulnar palm and dorsum of hand
Weakness of:
- FCU
- Ulnar half of FDP (small and ring finger)
- Intrinsics (thenar spared)
Atrophy (notable in first web space)
3. Provocative tests
Wartenburg sign (unable to adduct the small finger)
Froment sign
Tinels at the elbow
Flexion-compression test
- Manual compression over the ulnar nerve posterior to the medial epicondyle during elbow flexion
Scratch collapse test
- Examiner lightly scratches skin over the presumed area of nerve compression
  while the patient sustains resisted
  external rotation
- Allodynia caused by compression neuropathy is thought to impart a brief loss of muscle resistance after the stimulation
- Results collapse of the extremity under resistance
Ulnar nerve stability
- Palpate for ulnar nerve subluxation through ROM
  1. EMG findings
Decrease in absolute conduction velocity to <50 m/s or a relative drop in conduction velocity of ≥10 m/s across a measured interval around the elbow

Answer 109

A

Nonoperative
* Night splints
* Activity modification
Operative

In situ decompression
- Released ~6cm proximal and distal to elbow
- Release of:
  - FCU fascia
  - Osborne ligament
  - Medial triceps fascia
  - Arcade of Struthers
- Avoid circumferential dissection
  - Prevents devascularization and hypermobility
- Generally, hypermobility felt to be a contraindication
Anterior transposition
- Ulnar nerve is circumferentially decompressed
  - Inferior ulnar collateral artery is preserved
  - Medial intermuscular septum is excised
  - Ulnar nerve is transposed anteriorly
- Subcutaneous – preferred
- Intramuscular
- Submuscular
  - Indicated in thin patients or revision decompression
Medial epicondylectomy
- Ulnar nerve is decompressed and an oblique osteotomy of the epicondyle is made preserving MCL
- Promotes anterior translation of the ulnar nerve over the smooth osteotomized medial
  aspect of the elbow
  - Reduces neural strain more than in situ
    decompression
- Removal of >19% of the medial epicondyle
  compromises the anterior band of the MCL

Answer 110

A

Ligament of Struthers
Lacertus fibrosis
Two heads of pronator teres
Proximal arch of FDS (sublimus arch)
Accessory head of FDP (Gantzer muscle)
Aberrant radial artery
Carpal tunnel

Answer 111

A

Motor

Forearm
- Pronator teres
- FCR
- Palmaris longus
- FDS
- Radial FDP [AIN}
  - Index and middle finger
- FPL [AIN]
- Pronator quadratus [AIN]
Hand
- APB
- FDB (superficial head)
- OP
- Lumbricals 1 & 2
  1. Sensory
Volar wrist capsule
Radial palm
Palmar aspect of thumb, index, long and radial half of ring
Branches:
- Terminal AIN
- Palmar cutaneous branch of median nerve
- Terminal digital cutaneous branches

Answer 112

A

Proximal median nerve dysfunction/compression
Characterized by:
* Numbness and paraesthesia in median nerve distribution including palmar cutaneous branch
* Pain in volar forearm and wrist
* Minimal motor deficits
Entrapment sites

Classically, two heads of PT
Ligament of Struther
Lacertus fibrosus
Accessory head of FPL

Provocative tests

Pronator compression test
- Apply pressure proximal and lateral to the proximal edge of the PT muscle belly on the
  volar forearm
- Positive test = Pain or paresthesias within
  30 seconds of compression
Resisted pronation
Resisted elbow flexion and supination
Resisted middle PIP flexion
- Due to compression between heads of FDS
- Positive = pain/parasthesias
  - Also positive in CTS
Tinel over proximal volar forearm
5. EMG findings:
Typically negative

Answer 113

A

Believed to be related to neuritis (Parsonage-Turner), possibly compression
Characterized by:

Volar forearm pain
Weakness of:
- FPL
- Pronator quadratus
- Radial FDP (index and middle finger)
No sensory deficits

Provocative tests:
* Failed OK sign (Kiloh-Nevin test)
EMG findings:
* Denervation of muscles innervated by AIN

Answer 114

A

EIP

Order of Innervation:

Radial Nerve:
- Triceps
- Lateral 1/3 Brachialis
- Anconeus
- Bradioradialis
- ECRL
PIN:
- ECRB*
- Supinator
- ECU
- EDC
- EDM
- APL
- EPL
- EPB
- EIP
  - Last to return to function after PIN palsy

Answer 115

A

Fibrous band at the origin of the lateral head of triceps
Lateral intermuscular septum
Fascia adjacent to radiocapitellar joint
Thickened edge of ECRB
Recurrent radial vessels (Leash of Henry)
Arcade of Froshe

Fibrous arch of the proximal edge of supinator
3-5cm distal to epicondylar axis

Supinator fascia (most common)
Distal edge of supinator
Fascia between ECRL and BR

FREAS

F - Fibrous bands at the elbow

R - Radial recurrent vessels (Leash of Henry)

E - Extensor carpi radialis brevis (fibrous border of ECRB)

A - Arcade of Frohse

S - Supinator (fascia and distal border)

Answer 116

A

Compression of the radial nerve proximal to the arcade of Froshe
Radial Tunnel Borders:
* Proximal border – begins at radiocapitellar joint
* Distal border – arcade of Froshe
* Roof – BR
* Medial border – brachialis and biceps tendon
* Lateral border – ECRB, ECRL, BR
Characterized by:

Pain at lateral forearm distal to lateral epicondyle
Lack motor and sensory changes

Provocative maneuvers:

Pressure over supinator muscle in supinated position
Pain with resisted wrist or long finger extension

EMG findings:
* Often normal

Answer 117

A

Compression of the PIN
Characterized by:

Weakness of PIN innervated muscles
- Sparing of BR, ECRL
Pain in dorsal radial forearm
No sensory changes
3. Provocative maneuvers:
Wrist extension demonstrates radial deviation
- Intact ECRL
  1. EMG findings:
Denervation of PIN innervated muscles

Answer 118

A

Compression of the superficial radial nerve ~9cm proximal to radial styloid where the nerve passes between BR and ECRL
Characterized by:
* Dorsal radial forearm pain radiating to dorsoradial hand

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