POSTERIOR INSTABILITY

W.Jaap Willems,

Lairesse Kliniek

Amsterdam, The Netherlands

Disclosures

Consultant - Smith and Nephew

- Tornier

Reearch grants - Tornier

Classification

• Complete traumatic dislocation

- locked

- recurrent

• Traumatic subluxation: (involuntaryinstability)

• Voluntary instability

• Voluntary turned into involuntary instability

Etiology

Posterior shoulder instability

* Bigliani 1995, Bottoni 2005, Kim 2003 McIntyre 1997, Robinson 2005

• traumatic microtrauma atraumatic

• less laxity more laxity

• rec. dislocation provocative test

Etiology

• unidirectional multidirectional

• involuntary voluntary

Posterior shoulder instability

* Bigliani 1995, Bottoni 2005, Kim 2003 McIntyre 1997, Robinson 2005

Complete traumatic dislocation

• Dislocation w or w/o fractures

CM Robinson et al JBJS(A), 2007

• CT mandatory !

Traumatic dislocation

• Locked posterior dislocation

often missed at the Emergency department !

• Recurrent dislocation

M,57yrs, fall from bike

Only AP X rays taken

1 yr later……..

Treatment locked dislocation

• Acute without fracture: closed reduction, aneasthesia or plexus block

• Chronic: - open reduction

- allograft

- Mclaughlin (minor tuberosity transfer)

- HSA

Acute locked dislocation

“knocking out”

Chronic locked dislocation: reconstruction

• Allograft

Gerber, 1996,Miniaci, 2001

Recurrent traumatic dislocation

• Posterior Labro Periosteal Sleeve

• Avulsion (POLpsa)

• 45 yrs old alcoholic

refused a’scopy

Recurrent traumatic subluxation

• Etiology: acute trauma

or

recurrent microtrauma

• Symptoms : - posterior shoulder pain

- instability symptoms

Diagnostic tests

• Jerk test

• Posterior load and shift

• Sulcus sign

• Posterior apprehension test

• Hyperlaxity tests

Jerk test

• Dynamic test, simulates posterior subluxation and reproduces symptoms

• Axial posterior load onto a arm flexed at 90°, adducted and internally rotated

• Predictive measure for non-operative treatment

Kim, 2001

Jerk test

Pathophysiology

• Bony anatomic deformities

• Excessive capsular laxity

• Labral lesions

Bony changes in post instability

Labrum lesions

• Bankart lesion

Labrum lesions

• Perthes-like lesion

• Reversed H-Sachs (edema)

• Capsule lesions

• Reverse HAGL

Kim’s Lesion

• Incomplete and concealed avulsion postero-inferior labrum

Kim’s Lesion

• Paralabral cyst

Voluntary instability

• No indication for surgery

• However:

subset of patients, who start with VI

turning into involuntary instability

Treatment of posterior instability

• Open treatment modalities

• open capsulorraphy

• glenoid osteotomy

• bone block procedure

Open approach

Brodsky et al 1987

Open approach

Brodsky et al 1987

Glenoid osteotomy

• 32 pat ,5 yrs f-up

• 81% good or excellent,

• 25% degenerative changes

Graitchen et al,Int Orthop 1999

Glenoid osteotomy

• 29% complication

• 41% recurrence

Hawkins JBJSA 1984

Glenoid osteotomy

• Coracoid impingement

• Coracoplasty ?

Gerber et al, ClinOrthop 1987

Bone block

• 20 patients with involuntary instability

• Posterior bone block, 5-10 mm overhang

• 3 failures; 60% very satisfied, 40% satisfied

Walch et al, KSSTA 2007

Bone block

• High rate of osteoarthritis withlonger follow-upSirveaux RCO 2004, Meuffels JBJSB 2010

Open capsulorraphy

• Neer, 1981

Arthroscopic treatment

• with or without labral detachment

• labral repair +/- capsulorraphy

• rotator interval ?

Capsulorraphy

How much should we plicate ?

• Arthroscopy:Each stitch of 1 cm 10% volume reduction

Ponce et al, 2011

Posterior labral repair

• Comprehensive analysis open and @ soft tissue repair of posterior instability

Kakar et al Am.J Orthop 2007

open : 173 ( 9 studies)

@ : 186 ( 7 studies)

satisfaction and return to sports : equal

Thank you for your attention

POSTERIOR TRAUMATIC SUBLUXATION

• Bankart type lesion

• Cartilaginous reversed Hill Sachs

• Bennet lesion, 1941: post.bony spur in throwers

Bennett lesion

• Symptomatic when : -posterior joint laxity

- no deficit of int. rot.

Nakagawa et al, 2006

Posterior subluxations

• Jerk test : most reliable in post. Instability

Kim, 2004

POSTERIOR TRAUMATIC SUBLUXATION

• posterior Bankart, superficial rev H-S

POSTERIOR TRAUMATIC SUBLUXATION

• Reverse GARD, superficial rev H-S

POSTERIOR LABRUM AVULSION COMBINED WITH CAPSULAR TEAR

Reverse HAGL

ANATOMY OF POSTERIOR LABRUM

• Detrisac and Johnson:

• 2 types: -wedge labrum

-firmly attached

• wedge shaped

• firmly attached