Bigliani coined the term glenoid rim lesions glenoid rim erosion and bony Bankart lesion, Itoi et al. cadaveric study inferred that glenoid defect more than 21% produces anterior instability. Lo and Burkhart named significant bone loss as “inverted-pear glenoid” and “engaging Hill-Sachs lesion” shoulders associated with these significant bone loss are not suitable candidates for arthroscopic soft tissue stabilization X ray 2D CT scan 3D CT scan MRI Arthroscopy

1. D R S A M I R D W I D M U T H E
M S O R T H O D N B O R T H O
A R T H R O S O C P Y F E L L O W S O U T H K O R E A
I N T E G R A S P E C I A L T Y C L I N I C S , N A G P U R
Assessment Of Glenoid Bone Loss
In Recurrent Shoulder Dislocation

2. Overview
How it happens.
Implications of bone loss.
How to measure.
Which is best method.

3. Glenoid bone loss- HOW it happens
 Bigliani coined the term
glenoid rim lesions
 glenoid rim erosion and
 bony Bankart lesion,
 Itoi et al. cadaveric study
inferred that glenoid defect
more than 21% produces
anterior instability.

4. Lo and Burkhart named significant
bone loss as
“inverted-pear glenoid” and
“engaging Hill-Sachs lesion”
shoulders associated with these
significant bone loss are not suitable
candidates for arthroscopic soft
tissue stabilization

5. How it affects management
glenoid bone stock determines surgical success and affects
the type of surgical re- pair chosen
1-mild to moderate bone loss(less than 20%)- arthroscopic
soft-tissue stabilization alone
2- severe bone loss (20 -25 %) require bone augmentation
with open surgery
Only weak correlation exists between dislocation frequency
and glenoid bone loss.

6. Methods of assessment
 X ray
 2D CT scan
 3D CT scan
 MRI
 Arthroscopy

7. Bernageau view
 Good correlation with CT
with regard to the degree
of glenoid bone loss .
 The average discrepancy
in glenoid bone loss
measurements between
radiography and CT was
2.28% (range, 0%– 6.5%)
(Murachovsky)
X-rayimagesobtainedby the modified
Bernageau methods. a, Normal glenoid (a
black arrow indicates normal anterior glenoid
contour). b, Glenoid with bone defect (a white
arrow indicates the defect)

8. Disadvantages
 Difficult to quantify the loss.
 Glenoid shape and anatomy not seen.

9. 2D CT scan
 CT enables examination
of both shoulders
simultaneously.
 side-to-side glenoid
width is used to assess
glenoid bone loss.
 CT measurements of
glenoid bone loss show
good correlation with
arthroscopic
measurements.
A, Normal side shows normal curved anterior glenoid
rim (arrows). Glenoid width (solid line), measured at
right angles to long axis of glenoid (dashed line),
measures 28.4 mm.
B, On dislocated side, there is anterior straight line to
anterior glenoid rim (arrows). Glenoid width (solid
line), measured at right angles to long axis of glenoid
(dashed line), measures 24.7 mm. Glenoid bone loss is
difference in glenoid width (3.7 mm) divided by normal
width (28.4 mm) × 100 = 13% glenoid bone loss.

10. 3D CT scan
 The prevalence of glenoid
rim lesion has been
reported as high as 90 %,
 50 % of bony Bankart
lesion
 40 % of erosion
in shoulders with chronic
recurrent traumatic
anterior instability
3DCTimageswith humeral head
digitally subtracted. a, Normal
glenoid. b, Glenoid with bone defect

11. 3D CT scan
 The bone loss -ratio of
the surface area of
missing bone to the
surface area of a best-
fit circle over the
inferior glenoid using
3DCT
 This best-fit circle
method has been
validated by
Huijsmans et
The glenoid defect is defined as a ratio of
defect width (b) against the diameter of the
assumed inferior circle of the glenoid (a).
Sugaya H. Chapter 14. Instability with bone loss. In: Angelo,
Esch, Ryu, editors. AANA Advanced Arthroscopy: The Shoulder.
Philadel- phia: Elsevier; 2010. p.136–46.

12. Preoperative 3DCT benefits
 Surgeons can recognize glenoid shape and the degree
of bone loss intuitively at a glance;
 Accurate quantification of bone loss can be possible
by using an estimated inferior circle on the en face
view of 3DCT;
 Surgeons can easily assess the size and shape of the
bony fragment in shoulders with bony Bankart
lesion.

13. Disadvantages of 3D CT
 Radiation exposure.
 Time and cost involved.
 CT of both shoulders needed for comparison.

14. MRI
 Owens and co-workers
 the relationship between the height and width
was similar in sagittal images of MRI in
normal shoulder.
 Therefore, the expected glenoid width can be
easily estimated using glenoid height in
patients with glenoid anteroposterior bone
loss

16.  Advantages
 No radiation
 Only one shoulder MRI needed.
 Loss can be measured.

17.  The results of MR imaging in the assessment of
glenoid bone loss correlate well with the results of CT
and arthroscopy.
 When compared with arthroscopy, CT shows
marginally better correlation than MR imaging in the
measurement of glenoid bone loss because the best-
fit circle method used with MR imaging will not
always capture a noncircular configuration of the
inferior glenoid.

18. Arthroscopy
 Burkhart
 The percentage of bone
loss was calculated by
dividing measured
anterior distance by the
posterior distance from the
bare spot.
 Overestimation of bone
loss may be possible due to
anterior cartilage wear.

19. Pitfalls of arthroscopic bare spot technique
1. The bare spot may occasionally comprise a bare area rather than a discrete bare
spot.
2. The calibrated probe inserted via the posterior portal may not always be
aligned at right angles to the long axis of the glenoid.
3. The millimeter-spaced lines along the calibration probe are counted visually via
a second scope inserted through an anterosuperior portal.
4. A cadaveric study has shown that the bare area does not consistently lie in the
center of the glenoid and tends to lie closer to the anterior rather than the
posterior glenoid margin .
The mean difference between the anterior-to-posterior glenoid widths with the
bare spot as a reference was 4.2 mm (range, 0.9–8.9 mm).
Kralinger et al. recommend preoperative CT rather than arthroscopy to assess
glenoid bone loss in patients with shoulder dislocation

20. Comparison of 2D CT, 2D CT and MRI
 Rerko and colleagues estimated diagnostic accuracy
by comparing 3DCT with 2DCT, radiography, and
MRI using cadaveric specimen with native shoulders
and 3 sequential anteroinferior defects, and
concluded that 3DCT is the most accurate and
reliable imaging modality followed by 2DCT.

21. Summery
Assessment of glenoid bone loss helps in deciding the
best possible treatment plan for patients with
recurrent shoulder instability.
3-dimensionally reconstructed computed tomography
(3DCT) images with humeral head digitally
subtracted is gold standard when assessing glenoid
morphology and quantification of bone loss.
Decision regarding the type of surgery must be based
on combined assessment of Glenoid and Hill-Sach
lesion.

22. References
 Hiroyuki Sugaya Techniques to evaluate glenoid bone loss. Curr Rev
Musculoskelet Med. 2014 Mar; 7(1): 1–5.
 Eili ItoiNobuyuki Yamamoto, Daisuke Kurokawa, and Hirotaka Sano. Bone loss
in anterior instability. Curr Rev Musculoskelet Med. 2013 Mar; 6(1): 88–94.
 Burkhart SS, De Beer JF. Traumatic glenohumeral bone defects and their
relationship to failure of arthroscopic Bankart repairs: significance of the
inverted-pear glenoid and the humeral engaging Hill-Sachs
lesion. Arthroscopy. 2000;16:677–94. doi: 10.1053/jars.2000.17715.
 Rerko MA1, Pan X, Donaldson C, Jones GL, Bishop JY.Comparison of various
imaging techniques to quantify glenoid bone loss in shoulder instability. J
Shoulder Elbow Surg. 2013 Apr;22(4):528-34.
 Owens BD1, Burns TC, Campbell SE, Svoboda SJ, Cameron KLSimple method
of glenoid bone loss calculation using ipsilateral magnetic resonance imaging.
Am J Sports Med. 2013 Mar;41(3):622-4. d.

23. Thank you