GANZ ET AL
--refers to an abnormal bony bump at the
head neck junction of the femur .
--This nonspherical portion is usually found
--This abnormal ‘bump’ or insufficient concavity of
the femoral head-neck junction decreases femoral
head-neck offset and causes impingement on the
acetabular labrum and articular cartilage with daily
• Cartilage is affected
delamination of articular cartilage
then labrum is displaced outwards and superiorly.
Pincer impingement is an acetabular sided morphologic
abnormality characterized by over coverage of the femoral
The femoral head makes contact with the acetabulum due to
Unlike cam type ,labral lesions occurs before the cartilage
labrum is crushed causing intrasubstance tears and
sometimes para labral cysts.
With time , articular cartilage is also damaged.
Healing of labrum forms an ossified rim which further
worsens the acetabular coverage.
FOCAL – due to retroversion
GLOBAL – due to protruso acetabuli
-- active young adult (atheletes and ballet dancers)
-- slow growing groin pain
-- increased by prolonged walking or sitting
-- can be referred to the knee
--GAIT – antalgic
--ROM – flexion and internal rotation will be restricted
-- ANTERIOR IMPINGEMENT TEST
-- POSTERIOR IMPINGEMENT TEST
ACETABULAR RETROVERSION ( FOR PINCER LESIONS)
1> CROSS OVER SIGN – MILD
2>POSTERIOR WALL SIGN
The posterior wall sign: Normally the center of the femoral head lies medial
to the posterior wall. When it lies lateral to the posterior wall, the posterior wall
sign is said to be positive and implies a retroverted acetabulum. The sign also
reflects how much posterior wall coverage exists
FOR CAM LESIONS
--cross leg lateral view ,-- dunn view ,--modified dunn view
1– circle is drawn over femoral head which shows a smooth
contour .any lesion outside is a cam lesion.
2—ALPHA ANGLE – normal 42 , if > 50.5 diagnostic of a cam
CT SCAN / MRI
CT SCAN – 3D CT helps to identify exact size and location of
patholgy that helps in surgery
MRI SCAN – helps to find out soft tissue lesions like labral
tears , paralabral cysts, articular cartilage defects , cartilage
delamination, ossification of acetabular rim and loss of
sphericity of femoral head due to fibrocystic changes .
NON SURGICAL MANAGEMENT
--initial trial of conservative management includes
restriction of atheletic activities and Nsaids .
But sx rx is usually unsuccessful and operative rx is
-- joint space narrowing of 1-2mm
-- extent of damage to acetabular labral chondral complex
--severe acetabular retroversion
--femoral head asymmetry
--high riding GT in cam impingement
1– SURGICAL DISLOCATION AND TRIMMING OF CAM AND
2– CORRECTION BY ARTHROSCOPY
3– PERIACETABULAR OSTEOTOMY FOR FOCAL
4– TOTAL HIP REPLACEMENT
SURGICAL DISLOCATION OF HIP
-- cam type lesion
-- pincer type lesion
cam type lesion with 1mm of joint space reduction as this
approach would allow conversion to arthroplasty if needed.
--Cam type lesion without proximal femoral deformity.
--isolated acetabular retroversion with or without cam type
LIMITATIONS OF ARTHROSCOPY
-- steep learning curve
-- injury to neuro-vascular structures from the entry portals
-- incomplete removal or
-- excessive removal of bone at the cam lesion leading to a
CONSISTS OF 2 COMPONENTS
1– CENTRAL COMPARTMENT – which consists of labrum
and all parts medial to it
2– PERIPHERAL COMPARTMENT – which consists of parts
lateral to labrum but within the capsule and includes the
head neck junction
--acetabular retroversion with an associated posterior wall
(cartilage in the antero-superior area must be intact)