Rheumatoid Hand

Front 1

Which lab value is most often positive in RA? Alternative test?

Back 1

▀Rheumatoid factor (RF)

•RF seropositivity is present in 70%–80% of RA patients.

•Some patients become seropositive before development of symptoms.

•Some patients convert to seropositivity late in disease process.

•Some patients with RA always remain seronegative.

▀Anticitrullinated peptide antibody has high specificity for RA (88%–96%)

Front 2

How does Boutonniere deformity where the PIP is in flexion, & DIP is in hyperextension form in RA?

Back 2

▸Pannus erodes dorsally, rupturing central slip insertion, and PIP cannot extend.

▸Lateral bands subluxate volarly and act as PIP flexors and DIP extensors.

Hint 2

Swan neck deformity: PIP hyperextension, DIP flexion

Front 3

Two mechanisms of action for swan neck deformity that forms in RA?

Back 3

▸Unlike boutonniere deformity, can result from pathology at MP, PIP or DIP joint

▸DIP joint: Pannus erodes terminal tendon, and mallet finger develops. PIP hyperextension is secondary.

▸PIP joint: Pannus erodes volarly, stretching volar plate. (FDS) insertion can rupture, resulting in PIP hyperextension.

▸MP joint: Volar subluxation results in intrinsic muscle/tendon tightening overtime, and secondary PIP hyperextension.

Front 4

Which RA deformity is more disabling: swan neck or Boutonnière?

Back 4

When stiff or fixed, swan neck deformities are much more debilitating than boutonniere deformities. With boutonniere, patients can grip and pinch. With a swan neck, these motions are difficult or impossible.

Front 5

In RA, which flexor tendon is most likely to rupture?

Back 5

Flexor pollicis longus (FPL) rupture

▸Attrition rupture that occurs over sharp bony edge at scaphoid

▸Most common flexor tendon rupture, called the Mannerfelt lesion

Front 6

Which extensor rupture happens 1st in RA?

Back 6

▸Small finger extensors usually the first to rupture, and are often followed shortly in sequence by ring, long, and index extensors

▸This sequential rupture of extensor tendons, in ulnar to radial direction overtime, is called Vaughn-Jackson syndrome.

Front 7

Which RA medications most often need to be stopped at the time of surgery? For how long?

Back 7

In general, corticosteroids and methotrexate can be continued perioperatively. Biologic DMARDs should be withheld 2–4 weeks before and after surgery.

Front 8

Name the disease:

▀Seronegative spondyloarthropathy

▀DIP joints involved more than other joints (unlike RA)

▀Nail changes (pitting, other findings)

▀Pencil-in-cup radiographic changes

▀Can have arthritis mutilans

Back 8

PSORIATIC ARTHRITIS

Front 9

Main difference between RA & lupus hand disease?

Back 9

•Joints involved, but no cartilage destruction with normal joint spaces

•Hallmark: Ligamentous and volar plate laxity; tendon subluxation

•Deformity similar to RA, but with preservation of articular surfaces

Front 10

How is long term PIP joint range of motion following arthroplasty?

Back 10

No change over the long term, but improved pain.

Front 11

A 55-year-old woman comes to the office with progressive swelling around the wrist. Tendon rupture is suspected. Which of the following tendons is most likely to rupture in a patient with rheumatoid arthritis?

A) Extensor digitorum communis

B) Extensor digitorum manus

C) Extensor pollicis longus

D) Flexor digitorum profundus

E) Flexor pollicis longus

Back 11

A. The tendons involved most commonly are the extensor tendons on the ulnar aspect of the hand. Once the ulnar extensors rupture, the progression will advance radially to the remaining extensors. Other complications of rheumatoid arthritis can be confused with extensor tendon rupture and should be ruled out. These include metacarpophalangeal joint dislocation, extensor tendon displacement between the metacarpal heads, and paralysis of the common extensor muscle.

Front 12

Which hand tendon is 2nd most likely to rupture in RA?

Back 12

Extensor pollicis longus rupture is the second most common rupture found in rheumatoid disease of the hand, and it is diagnosed by an inability to extend the interphalangeal joint of the thumb.

Front 13

How is trigger finger treatment different in RA?

Back 13

This is true in patients with rheumatoid arthritis as well. When patients have failed conservative treatment with steroid injection, surgery is indicated. Normally, division of the A1 pulley results in excellent success. However, in the case of a rheumatoid patient, the A1 pulley is often the only remaining structure preventing ulnar drift of the tendons and joints. As a result, the A1 pulley should never be divided in a rheumatoid patient. The most appropriate surgical treatment is flexor tenosynovectomy and removal of intratendinous nodules. If this is unsuccessful, removal of a slip of the superficialis tendon is appropriate.

Front 14

30-year-old man sustains a laceration to the radial nerve at the mid-humerus level. Physical examination shows wristdrop. Which transfer is most commonly used to restore wrist extension in this patient?

Back 14

Pronator teres to extensor carpi radialis brevis (ECRB) transfer is well described for restoration of wrist extension in isolated radial nerve injury or palsy. The pronator teres is harvested from its insertion on the radius along with an extension of radius periosteum (necessary to have sufficient length for the transfer) and is woven either end-to-end into the ECRB or end-to-side into the ECRB if the surgeon feels the ECRB may recover some function.

Front 15

A 30-year-old man is referred for poor thumb opposition following an injury to the median nerve at the level of the wrist of the dominant right hand sustained 18 months ago. Physical examination shows strong function of the flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) of the little, ring, long, and index fingers. Extension of the wrist, fingers, and thumb is also strong. Which of the following tendon transfers into the abductor pollicis brevis insertion is most appropriate for correction of the deficit in this patient?

A ) Transfer of the extensor carpi radialis brevis

B ) Transfer of the extensor indicis proprius

C ) Transfer of the FDP of the ring finger

D ) Transfer of the flexor carpi ulnaris

E ) Transfer of the flexor palmaris longus

Back 15

The correct response is Option B.

The patient described most likely has a low median nerve palsy marked only by loss of opposition. The FDS of all the fingers and the FDP of the index and long fingers are functional. High median nerve palsy would result in loss of all FDS function, loss of FDP function of the index and long fingers, and loss of flexor palmaris longus function. Therefore, a tendon transfer that specifically addresses opposition is necessary.

Transfer of either the FDS of the ring finger or the extensor indicis proprius (EIP) is appropriate. FDS transfer requires formation of a pulley at approximately the level of the pisiform. This is most easily created using the ulnar half of the flexor carpi ulnaris tendon.

The EIP tendon is long and can be easily routed around the ulnar aspect of the forearm and still reach the thumb proximal phalanx, obviating the need for a pulley. This tendon transfer is considered by many authors to be superior to the FDS transfer because possible adhesion formation to a constructed pulley is avoided.

Front 16

Most common thumb deformity in long standing RA? Second most common?

Back 16

1. Boutonnière

2. Swan neck

Front 17

What would be the likely explanation for ongoing weakness and deformity of the thumb following LRTI of the thumb basal joint?

Back 17

Hypertension at the MCP joint, which would have been pre-existing & compensatory

Front 18

What is the cause of EDC rupture in RA, at the wrist? What is the treatment for the cause?

Back 18

Darrach procedure, or distal ulna resection, is a well-established procedure to treat distal radioulnar joint (DRUJ) arthritis and distal ulnar instability such as in caput ulnae syndrome.

Front 19

How is FPL rupture treated in RA?

Back 19

Treatment options include FDS tendon transfer and palmaris longus tendon graft.

Hint 19

2 different options

Front 20

A 65-year-old woman comes to the office because she is unable to actively extend the left ring and small fingers. Medical history includes rheumatoid arthritis and no marked trauma. On physical examination, the ring and small fingers are held in 45 degrees of flexion with ulnar deviation at the metacarpophalangeal (MCP) joints. Mild swelling around the MCP joints of all fingers and a prominent ulnar head are noted. The patient is able to maintain extension when her fingers are passively extended. X-ray studies show moderate to severe wrist arthritis but minimal arthritic changes of the finger joints. What’s the problem?

Back 20

Ulnar subluxation of the extensor mechanism at the MCP joint. Attenuation of the radial sagittal band of the MCP joint from inflammation and ulnarly directed forces from pinch and grip may result in ulnar subluxation of the extensor mechanism. The extensor tendons will slide into the valley between the metacarpal heads and the extensor tendon will place a flexion force on the MCP joint. In this case, passive extension of the fingers will centralize the extensor and the patient will be able to maintain the fingers actively in an extended position. This is the critical physical exam maneuver to diagnose this issue and the key to the patient in this question.