As with the wrist, start with screening tests. This will allow you to identify key pathologies and focus your examination on those areas.

The screening test involves the three steps look, move and feel. Examine both hands together compare and help identify any pathology.

Once a diagnosis is reached (often during the screening phase), carry out specific tests and then a functional assessment.

Screening

Look

Examine the palmar surface first
Ask the patient to make a fist and look for:

• Range of motion
• Cascade of the digits
• Flexion deformities

Turn the hands over to examine the dorsum of the hand
Make a fist in this position
Flex the elbows to assess the forearm and ulnar border of the hand and wrist

1. Scars
2. Rheumatoid nodules
3. Psoriatic plaques

Key things to pick up on are:

• Swelling
• Wasting
• Contractures/ abnormal movement
• Scars
• Colour changes
• Nail deformities
• Position/ attitude of the thumb or fingers

Abnormal movement in a joint could be due to an acute tendon or nerve injury, or from a chronic contracture, such as from previous trauma, neurological insult, Dupuytren’s disease or arthropathy.

Assess whether the contracture/ deformity is fixed (e.g. Dupuytren’s/ scarring) or passively correctible (e.g. acute tendon injury)

Normal range of motion of finger joints:

MCP Joint

• Extension:        0-45° hyperextension
• Flexion:            90°

PIP Joint

• Extension         0°
• Flexion             100°

DIP Joint

• Extension:        0°
• Flexion:            80° 

Normal range of motion of thumb joints:

CMC Joint

• Adduction/ flexion:       contact with palm
• Abduction:                    60°
• Extension:                    45°

MCP Joint

• Extension:                    10° hyperextension
• Flexion:                        55°

IP Joint

• Extension:                    15° hyperextension
• Flexion:                        80°

Contractures 

Dupuytren’s disease

Most commonly affects the ring finger MCPJ +/- IPJ, then small and middle fingers. Assess skin quality as skin grafting may be necessary during surgery.

Look 

• Which fingers/ joints?
• Thumb involved?
• Both hands?
• Nodules/ cords
• Garrod’s pads
• Pitting
• Scars (e.g. from previous surgery)
• Systemic associations

- Peyronie’s disease
- Plantar fibromatoses

Feel

• Nodules?
• Cords?
• Digital Allen’s test

Move

• Hueston’s table top test

- Place palm of hand flat on table
- Contractures of MCPJ or PIPJ prevent this
- Surgery may be indicate

Tendon injuries

Loss of tendon function can be due to rupture or scarring from direct trauma, previous surgery or synovitis from an inflammatory arthropathy.

Consider a nerve injury causing loss of motor function and assess using the tenodesis effect

Where a tendon injury is present, consider reconstructive options and assess potential donor tendons. 

Look:

• Scars/ wounds
• Features of inflammatory arthropathy

Feel:

• Scarring
• Adhesions

Move:

• Passively correctible?
• Tenodesis
• Nerve injury?
• Specific tests as described below

Video 2.Tenodesis effect.To assess the tenodesis effect, relax the patient’s hand and wrist and move the wrist from flexed to extended and watch the fingers. Where the tendons are intact (i.e. in a nerve injury), the fingers will follow a normal cascade. Where a tendon is damaged, there may be abnormal (or no) movement of the digit.

Flexor tendon pathology

Flexor digitorum profundus (FDP):

• Extend the fingers
• Isolate the DIP Joint and ask the patient to flex the DIP Joint
• Compare movement and strength against resistance to other digits/ hand

Quadrigia effect:

• FDP tendons have a common muscle belly
• Scarring of one FDP tendon can have an effect on other FDP tendons, reducing their movement

Lumbrical plus:

• Paradoxical extension of IPJs of fingers when flexing at the MCPJ/ making a fist
• FDP injury distal to lumbrical insertion (or reconstruction with graft that is too long)
• FDP retracts proximally, pulling lumbrical with it
• FDP contraction when attempting to flex the finger tightens it further
• Lumbricals pull on lateral bands extending the PIPJ and DIPJ.

Figure 5.Testing FDP

Flexor digitorum superficialis (FDS):

• Exclude FDP by holding all other fingers extended
• Ask the patient to flex the finger

Flexor pollicis longus (FPL):

• Mannerfelt lesion
• Caused by attrition over scaphoid osteophytes, common in rheumatoid arthritis
• Unable to flex IPJ of thumb

Extensor tendon pathology

Differentiate extensor tendon injuries from sagittal band ruptures or PIN palsy

Mallet deformity

• Avulsion/ injury to extensor tendon distal to DIPJ
• Distal phalanx of finger held in a positon of flexion
• Passive extension of joint possible but patient is unable to hold the distal phalanx extended

Boutonniere deformity

• Avulsion/ injury to central slip of extensor tendon
• PIPJ flexion and DIPJ hyperextension
• Secondary volar displacement of lateral bands worsen deformity
• Can be correctible or fixed if chronic

Elson’s test

• Assesses central slip function
• Rest the patient’s palm on the edge of a table and flex the PIP Joint of the affected finger to 90° over the edge
• Ask the patient to extend the PIP Joint against resistance
• Positive test: weakness of extension with stiffening/ hyperextension of the DIP Joint (as only lateral bands are activated to extend digit)

Video 3 .Elson's test

Extensor pollicis longus (EPL) rupture

• Rupture due to direct trauma, chronic synovitis or attrition over osteophytes, metalwork or a distal radius fracture
• Thumb may be held adducted and may be flexed at IP Joint
• Unable to retropulse thumb
• Assess for causes of rupture

Proximal extensor tendon rupture

• Due to trauma or synovitis
• Vaughan-Jackson syndrome is rupture of the extensor tendons due to synovitis/ attrition on a prominent ulnar head, commonly seen in rheumatoid arthritis. The small finger is most commonly affected, succeeded by ring and middle finger involvement.

Sagittal band rupture

• Can be post traumatic (e.g. ‘Boxer’s knuckle’) or due to synovitis from an inflammatory arthropathy
• Subluxation of extensor tendon causes an inability to actively extend MCPJ of affected digit
• Passive extension possible (and relocates the tendon) so patient is able to hold the digit extended

Extensor indicis proprius (EIP)/ extensor digit minimi (EDM)

• Not commonly involved in pathology however can be used as tendon transfers
• Assess by eliminating extensor digitorum communis (EDC) tendons as in the picture shown

Figure 9.Testing EIP/ EDM

Arthropathies

Osteoarthritis

Thumb CMC Joint osteoarthritis

Look

• Prominent base of thumb
• Thumb metacarpal adduction (‘thumb in hand’ appearance)
• MCP Joint hyperextension

Feel

• Tenderness over CMC Joint
• Early stages predominantly on volar aspect, advanced stage throughout joint

Move

• Assess movements
• Grind test

- Grinds metacarpal base against trapezium
- Hold trapezium with one hand to prevent force being transmitted to proximal structures
- With your other hand, hold the thumb and apply compression and rotation across the joint
- Positive result: reproduction of pain

Figure 10 Thumb movements.(a)Adduction (b)Abduction (c)Flexion (d)Extension (e)Retropulsion

Video 4.Grind test 1st CMC OA

IP Joint OA

DIP Joint:

• Commonest arthritis in the hand
• Osteophytes form Heberden’s nodes
• Stiffness/ reduced range of motion
• Mucous (ganglion) cysts can cause nail deformities, pain and reduced range of motion

PIP Joint

• Osteophytes form Bouchard’s nodes
• Stiffness/ reduced range of motion

Inflammatory Arthropathies

Rheumatoid Arthritis

Bilateral polyarthropathy affecting upper and lower limbs as well as spine.

Once you identify specific abnormalities in your screening, focus on assessing the individual pathology.

Forearm

• Rheumatoid nodules

Wrist

• Swelling/ synovitis
• Radial deviation, volar subluxation, ulnar translation
• Caput ulna (prominent ulna due to dorsal subluxation of ulnar head)

           - Assess DRUJ instability

           - Look for Vaughan-Jackson syndrome (extensor tendon rupture)

MCP Joint

• Synovitis
• Volar subluxation and ulnar deviation
• Assess:

          - Reducible subluxation/ dislocation?

           - Sagittal band rupture?

           - Assess extensor tendon function

Fingers

• Boutonniere deformity
• Swan neck deformity

            - Volar plate erosion leading to PIPJ hyperextension and muscle imbalance

Thumb

• Z deformity

           - Boutonniere deformity

           - MCPJ fixed flexion

           - IPJ hyperextension

           - CMCJ subluxation

• FPL (Mannerfelt lesion)/ EPL rupture
• Thumb triggering

Tendon pathology is covered in more detail elsewhere, however for the purposes of assessing pathology in RA, the key differential diagnoses/ pathology to rule out is summarised here.

Extensor tendon rupture/ Vaughan-Jackson syndrome

• MCPJ dislocation/ subluxation?
• Sagittal band rupture?
• Posterior interosseous nerve (PIN) palsy?
• Assess EIP as an option for tendon transfer

Flexor tendon rupture (commonly FPL/ Mannerfelt lesion)

• Trigger thumb?
• Anterior interosseous nerve (AIN) palsy?

Psoriatic arthritis

Arthritis mutilans

• Psoriatic plaques on forearms
• Nail pitting
• Dactylitis in up to 35%
• With joint destruction, digits can shorten causing redundant overlying 

Functional assessment

The decision to operate on a condition is often affected by the patient’s function. Carry a pen, a key and a coin with you to assess this.

Functions to assess are:

• Grasp

           - Shake/ squeeze examiner’s hand

• Side pinch

            - Hold a key

• Chuck pinch

            - Pick up a coin from the examiner’s hand

• End pinch

           - Hold a pen

Figure 11 Functional assessment.(a)Grasp (b)Side pinch (c)Chuck pinch (d)End pinch

Neurovascular assessment

Neurological assessment is discussed in more detail in the next section but a quick screening test can identify gross motor and sensory function of the median, radial and ulnar nerves.

Allen’s test can be used to assess perfusion, especially important if operating on a volar ganglion in close proximity to the radial nerve

Video 5.Allen’s test.Pressure is applied to both radial and ulnar arteries, resulting in the hand turning white as perfusion is arrested. Release the pressure on the radial artery and assess reperfusion, then repeat for the ulnar artery