NJR data reports that the majority of surgeons use a cemented stem for hemiarthroplasty in fractured neck of femur patients. For those that use an uncemented implant this simple tool can help predict those patients in whom the risk of fracture is high and where a cemented implant should be further considered.

1. Predicting Intra-operative Periprosthetic Fracture
During Uncemented Hemiarthroplasty for
Intracapsular Neck of Femur Fractures
Harpal Uppal, Anil Dhadwal, Ben Dean, Partha Bose, Adnan
Saithna
British Trauma Society Annual Meeting 2015
5th November 2015

2. Introduction
• In the UK majority of patients sustaining intracapsular neck of femur fractures are
treated with a hemiarthroplasty1
• Uncemented technique has been deemed safer as it avoids cement related
complications and are associated with shorter operating times and thus favoured in
frail, elderly patients with multiple co-morbidities
• Parker et al reported in 2010 that there was no statistical significance difference in
mortality or post-operative medical complications2. This was later supported by the
Cochrane review from the same author3
• Australian NJR revision rate is higher in uncemented prostheses4
• Current NICE guidance for management of displaced intracapsular neck of femur
fractures is cemented hemiarthroplasty5
• NHFD 2013 reports that 15.8% of all hemiarthroplasties are uncemented6

3. Austin Moore Prosthesis
• Developed in the 1950s
• Minor ammendments over the last 60
years
• Mono-bloc implant with keel
• Popular Low cost option used in many
organisations including the study
institution7
• Number of studies associated with
increased risk of peri-prosthetic
fracture8,9

4. Aim
Determine whether simple measurements performed on plain
radiographs could provide information about risk of peri-
prosthetic fracture
Objective
The objective of this study was to develop a simple tool to be
used at the pre-operative planning stage to assess patients for
the risk of intra-operative fracture

5. Methods
• Single centre study (Alexandra Hospital, Redditch)
• 258 consecutive patients who underwent hip
hemiarthroplasties identified on hospital theatre
management system
• Duration of Study – 3 years
• Operation notes, patient records and plain films
radiographs reviewed independently by two observers
• Fractures classified using Vancouver system10

6. Method of Radiological Evaluation
- Sen et al11
• Magnification of
radiographs
• Ratio of radiograph size
and actual implant size
• Femur Canal Diameter
then measured at three
levels (perpendicular to
shaft)
– A. Upper Lesser trochanter
– B. Lower lesser trochanter
– C. 75mm distal to LLT
Figure 1: Plain film radiograph
illustrating sites of canal measurements

7. Analysis
• Anonymised data collection
• Other Parameters measured
– Age, gender, seniority of
surgeon
• Matlab7.0 software used by
statistician
• Two patient cohorts
– No intra-operative fractures
(Group A) vs intra-operative
fracture (Group B)
• Bootstrapping and non-
parametric testing
• Kolmogorov Smirnov two-
sample test for comparison
of the two groups
– Does not make any
distributional assumptions

8. Results
• 235 patients included
• 5.5% (13) patients suffered intra-
operative fractures
• All patients were treated successfully
with cerclage wires
• Grade of surgeon did not have a
prognostic influence
– χ2 with Yates correction = 0.11 (p=0.025)
• Sex did not have a prognostic
influence
– χ2 with Yates correction = 0.025 (p=0.9
79%
21%
Fig. 2 Vancouver classification
of periprosthetic fractures
sustained in Group B
Vancouver A
Vancouver B

9. Figure 3a/3b
Histogram(a) and
Boot strap
distribution (b) for
Age in Cohorts A and
B
Histogram
demonstrates that
the population does
not fit a normal
distribution
Average age in non-
fracture group was 83
years old and 85 in
fracture group

10. Figure 4a / 4b
Histogram(a) and
Boot strap
distribution (b) Upper
Border of Lesser
Trochanter (Upper LT)
measurements
Bootstrapping
distribution suggests
that patients with an
Upper LT diameter
greater than 38.5mm
are at greater risk of
peri-prosthetic fracture

11. Figure 5a/5b Lower
Histogram(a) and
Boot strap
distribution (b)
Border of Lesser
Trochanter (Lesser
LT) measurements
Bootstrapping
distribution suggests
that patients with an
Lower LT diameter
greater than 26mm are
at greater risk of peri-
prosthetic fracture

12. Figure 6a/6b
Histogram(a) and
Boot strap distribution
(b) 75mm lower than
Lesser Trochanter
measurements
Bootstrapping
distribution suggests that
patients with that there is
a similar distribution
between Group A and
Group B
Femoral diameter was
increased marginally in
the Group B distribution

13. Discussion
• Osteoporosis is a major risk factor for intraoperative peri-prosthetic fracture when using
an uncemented implant
• Osteoporosis is associated not only with proximal femoral cortical thinning but also
increased marrow star volume12
• Study demonstrates patients who have upper and lower LT widths of greater than 38.5
mm and 26 mm respectively are at greater risk of intra-operative fracture
• Previous literature has supported our findings using the Dorr Classification13, 14
• We provide a more quantifiable approach to risk stratification providing patient has a
calibrating plain film at time of injury
• Our study does not look to advocate one implant over another

14. Limitations
• AMH was the only hemiarthroplasty implant available at
the study centre
• The more modern uncemented stems may have different
geometry and not behave in the same way
• Patients were not risk stratified with regards other
recognised risk factors
• Authors still feel that the study offers a pragmatic approach
as patients presenting with fragility fractures often have
multiple co-morbidities

15. Conclusion
• Uncemented hemiarthroplasty of the hip is associated
with an increased risk of peri-prosthetic fracture
• Pre-operative measurements of the femoral canal at
upper and lower borders of the lesser trochanter can
aid decision making
• Upper LT >38.5mm and Lower LT>26mm show
statistical significance authors would recommend using
a cemented implant and technique as opposed to an
AMH

16. References
1. Jameson SS, Jensen CD, Elson DW, Johnson A, Nachtsheim C, Rangan A, Muller SD, Reed MR. Cemented versus cementless hemiarthroplasty
for intracapsular neck of femur
fracture—A comparison of 60,848 matched patients using national data. Injury, Int. J. Care Injured 2013; 44: 730–734
2. Parker MI, Pryor G, Gurusamy K. Cemented versus uncemented hemiarthroplasty for intracapsular hip fractures: A randomised controlled trial
in 400 patients. J Bone Joint Surg Br 2010; 92(1): 116-22.
3. Parker MJ, Gurusamy KS, Azegami S. Arthroplasties (with and without bone
cement) for proximal femoral fractures in adults. Cochrane Database Systematic
Reviews 2010; 6: CD001706.
4. No-authors-listed. Australian Orthopaedic Association, National Joint Replacement
Register 2010. Available from: https://aoanjrr.dmac.adelaide.edu.au/annual-reports-2010 [accessed 02.08.14].
5. National Institute for Health and Clinical Effectiveness. The management of hip
fracture in adults 2011. Available from: http://www.nice.org.uk/nicemedia/
live/13489/54919/54919.pdf [accessed 02.08.14].
6. No-authors-listed. National Hip Fracture Database National Report 2013.
Available from: http://www.nhfd.co.uk [accessed 02.08.14].
7. Crossman PT, Khan RJ, MacDowell A, Gardner AC, Reddy NS, Keene GS. A survey of the treatment of displaced intracapsular femoral neck
fractures in the UK. Injury 2002; 33 5: 383–6.
8. McGraw IWW, Spence SC, Baird EJ, Eckhardt SM, Ayana GE. Incidence of periprosthetic fractures after hip hemiarthroplasty: Are uncemented
prostheses unsafe?
Injury, Int. J. Care Injured 2013; 44: 1945–1948
9. Phillips JRA, Moran CG, MAktelow ARJ. Periprosthetic fractures around hip hemiarthroplasty performed for hip fracture
Injury, Int. J. Care Injured 2013; 44: 757–762
10. Duncan CP, Masri BA. Fractures of the femur after hip replacement. Instr Course Lect. 1995; 44: 293–304
11. Sen RK, Tripathy SK, Kumar R, Kumar A, Dhatt S, Dhillon MS, et al. Proximal femoral medullary canal diameters in Indians: correlation
between anatomic, radiographic, and computed tomographic measurements. J Orthop Surg (Hong Kong). 2010; 18(2): 189-94.
12. Blain H, Chavassieux P, Portero-Muzya N, Bonnel F, Canovasc F, Chammasc M, Maury P, Delmasa PD. Cortical and trabecular bone
distribution in the femoral neck in osteoporosis and osteoarthritis. Bone 2008; 43(5): Pages 862–868
13. Nash W, Harris A. The Dorr type and cortical thickness index of the proximal femur for predicting peri-operative complications during
hemiarthroplasty. Journal of Orthopaedic Surgery (Hong Kong) 2014;22(1):92-95.
14. Kendrick BJ, Wilson HA, Lippett JE, McAndrew AR, Andrade AJ. Corail uncemented hemiarthroplasty with a Cathcart head for intracapsular
hip fractures. Bone Joint J 2013; 95-B(11): 1538-43

17. Thank you for listening
Any Questions?