Just B

Posterolateral Rotatory Instability

- PLRI

Posterolateral rotatory instability (PLRI) is a rare condition where the elbow keeps giving way or nearly

giving way.

The elbow may feel loose or slide out of joint, particularly when pushing up from an arm chair.

Recurrent painful clicking, snapping, clunking, or locking of the elbow are common complaints.

PLRI is most common after previous dislocations of the elbow if the ligaments don't heal properly. It

may happen spontaneously in some patients who's ligaments are very lax and hypermobile.

It may also be a complication of some types of surgery on the lateral aspect (outside) of the elbow.

The underlying problem is the lateral collateral ligaments either stretch out or don't heal down properly, this allows the radial head to rotate

out under the capitellum and the elbow may partially or totally dislocate.

Normal x ray of elbow

Radial head

Capitellum

Diagnosis

The diagnosis may not be clear initially. Physical examination may be normal. Muscle tone and pain often limits simulating the dislocation in

clinic. X rays are often normal.

Some provocation tests may be done in the clinic.

• Doing a push up with the arms wide apart and hands supinated (hands pointing to sides)

• Doing a one arm push up on the side of a table

• Sitting up from the chair pushing up with your arms hands supinated (hands pointing backwards)

An MRI scan may be requested to exclude other causes of lateral sided (outer side) elbow pain.

The definitive diagnosis may only be made during an examination under anaesthetic where the muscles are fully relaxed. An arthroscopy may

also be performed to see the state of the joint surface. Dynamic examination while taking x rays may also demonstrate injury to other

ligamentous structures around the elbow.

Treatment

Non operative

Activity modification, avoid activities that lead to episodes of subluxation. The elbow is most at rest when it is fully straight and the forearm/

hand supinated. It is best to perform stressful activities with the elbow bent. Elbow braces themselves are unlikely to help prevent

subluxation, short of reminding you to avoid risky positions.

Operative

Surgery is indicated if non operative treatment fails. Surgery involves repair and tightening of the lateral ligament ligament if enough good

quality tissue is present. If not suitable for direct repair then reconstruction with a tendon graft may be required.

References

Janak A. Mehta and Gregory I. Bain; Posterolateral Rotatory Instability of the Elbow; J. Am. Acad. Ortho. Surg., November/December 2004; 12:

405 - 415

Charalambous CP, Stanley JK; Posterolateral rotatory instability of the elbow; J Bone Joint Surg Br. 2008 Mar;90(3):272-9.

Posterolateral Rotatory

Instability - PLRI

Posterolateral rotatory instability (PLRI) is a rare condition where the

elbow keeps giving way or nearly giving way.

The elbow may feel loose or

slide out of joint, particularly

when pushing up from an arm

chair.

Recurrent painful clicking,

snapping, clunking, or locking

of the elbow are common

complaints.

PLRI is most common after

previous dislocations of the

elbow if the ligaments don't

heal properly. It may happen

spontaneously in some

patients who's ligaments are very lax and hypermobile.

It may also be a complication of some types of surgery on the lateral

aspect (outside) of the elbow.

The underlying problem is the lateral collateral ligaments either stretch

out or don't heal down properly, this allows the radial head to rotate out

under the capitellum and the elbow may partially or totally dislocate.

Normal x ray of elbow

Radial head

Capitellum

Diagnosis

The diagnosis may not be clear initially. Physical examination may be

normal. Muscle tone and pain often limits simulating the dislocation in

clinic. X rays are often normal.

Some provocation tests may be done in the clinic.

• Doing a push up with the arms wide apart and hands supinated

(hands pointing to sides)

• Doing a one arm push up on the side of a table

• Sitting up from the chair pushing up with your arms hands

supinated (hands pointing backwards)

An MRI scan may be requested to exclude other causes of lateral sided

(outer side) elbow pain.

The definitive diagnosis may only be made during an examination under

anaesthetic where the muscles are fully relaxed. An arthroscopy may

also be performed to see the state of the joint surface. Dynamic

examination while taking x rays may also demonstrate injury to other

ligamentous structures around the elbow.

Treatment

Non operative

Activity modification, avoid activities that lead to episodes of

subluxation. The elbow is most at rest when it is fully straight and the

forearm/ hand supinated. It is best to perform stressful activities with

the elbow bent. Elbow braces themselves are unlikely to help prevent

subluxation, short of reminding you to avoid risky positions.

Operative

Surgery is indicated if non operative treatment fails. Surgery involves

repair and tightening of the lateral ligament ligament if enough good

quality tissue is present. If not suitable for direct repair then

reconstruction with a tendon graft may be required.

References

Janak A. Mehta and Gregory I. Bain; Posterolateral Rotatory Instability of

the Elbow; J. Am. Acad. Ortho. Surg., November/December 2004; 12: 405

- 415

Charalambous CP, Stanley JK; Posterolateral rotatory instability of the

elbow; J Bone Joint Surg Br. 2008 Mar;90(3):272-9.