Subtrochanteric femoral fracture anatomy, classification and comparison of management options

1. By Hiren M Divecha (CT2)
NMGH
3/2/2010

2. • 10 -30% of hip fractures
• Bimodal age distribution
– 20-40yrs
• HIGH ENERGY
• RTA, fall from height, GSW (10%)
– >60yrs
• low energy
• Simple fall, osteoporotic, pathological (17-35%)
• Cann. screws below lesser troch
• Bisphosphonate Rx

3. • Screws must not enter lateral femoral cortex
below level of lesser troch
– Kloen et al JOT 2003
• Triangular configurations
– Highest load to failure
– Apex superior – higher risk of subtroch #
– Selvan et al Injury 2004, Lichtblau et al Bull NYU
Hosp Jt Dis 2008

5. • Inhibited remodelling leads to accumulation of
microdamage
• Associated with >7yrs use
• Prodromal thigh pain
• Cortical thickening, unicortical beak
• Simple transverse/ oblique pattern
• Bilateral (Capeci JBJS-Am 2009)
• Goh JBJS-Br 2007, Lenart NEJM 2008, Neviaser
JOT 2008, Kewkwa Injury 2008

6. • Between lesser trochanter and 5cm distal
• Stresses
– Posteromedial – compressive
– Lateral – tensile
– 6 x BW
• Cortico-cancellous junction
– Vascularity
– Healing

8. • Proximal fragment
– Flexed – iliopsoas
– Ext rot – iliopsoas + short ext rots
– Abducted – gluteus med + min
• Distal fragment
– Adducted/ varus – adductors
– Shortened – quads/ hamstrings

10. Proximal Border Distal Border Subdivisions
Boyd & Griffin 1949 2
Fielding 1966 PBLT 5cm 4
Zickel 1976 PBLT 10cm 6
Seinsheimer 1978 DBLT 5cm 7
Russell & Taylor 1987 3
AO Muller 1990 DBLT 3cm 9
Parker & Pryor 1994 DBLT 5cm

11. 1. <2mm displacement
2. 2-parts
A. Transverse
B. Spiral. Less troch prox
C. Spiral. Less troch distal
3. 3-parts
A. Less troch butterfly
B. Lateral butterfly
4. 4-parts or comminuted
5. Greater troch extension

12. • History
• Pain, NWB, deformity of thigh
• Open/ closed injury
• Neurovascular status
• Full ATLS
– Haemorrhagic shock
– Cranial, thoracic, abdominal injuries (Waddell’s
triad)

13. • Analgesia, femoral nerve block???
– Significantly reduced pain scores and use of opiates
– AK Fletcher et al. Ann Emerg Med. 2003;41:227-233
• Thomas splint
• X-rays
– AP pelvis
– full length femur views
– Contralateral femur (bisphosphonate Rx)
• Pathological
– Full assessment
– Bloods – myeloma screen, bone profile, LFTs
– Bone scan, MRI

14. • Unfit for surgery, open #s
• Skeletal traction
– Hamilton-Russell
– Perkins
• 90-90 position
• Aim for
– <5 varus/valgus
– >25% cortical apposition
– <1cm shortening
– No axial rotation
• Weekly x-rays + adjustments
• Traction until signs of union (8-12 weeks)
• Problems
– Pressure ulcers, VTE, pneumonia

15. Author Date No. Satisfactory Non-union
Watson 1964 8 50
Seinsheimer 1978 8 48 0
Velasco & 1978 22 50 0
Comfort
Waddell 1979 18 56 11
DeLee 1981 15 100 0
Bajaj 1988 23 83 0

17. • Key issues
– Medial cortical buttress
– Reduction (esp varus deformity)
• Extramedullary
– ORIF
– DHS, Medoff Sliding Plate, DCS, blade plate, locking plates
• Intramedullary
– Centromedullary
– Cephalomedullary
– Short vs long

18. Bending moment = F x D
d1 d2
d1 > d2

19. • Technically demanding
• Soft tissue dissection
• Plate/ screw breakage
• 30% failure
– Elderly
– Unstable #s
– Early weight bearing
• Nonunions

21. • Easier to insert than
blade plate
• Plate/ screw breakage
• 20-30% failure
– Elderly
– Unstable #s
– Early weight bearing
• Nonunions

23. • Designed for
intertrochanteric #s
• Easier to insert
• Entry point may be #
• 25% failure
– Loss of fixation
• ? Should be avoided

25. • Resist axial loading better • Less stiff in torsion
• Closed Rx • Short nails = femoral shaft
– Preserve fracture biology fracture
• Decreased moment arm • Femoral head screw cut
on implant out
• ? Autogenous grafting
during reaming
• Segmental/ pathological #
• >97% union

28. • Tencer J Orth Res 1984
– Cadaveric study
– Torsional stiffness better in plate devices
– Axial loading better in locked IM nails
– IM nail=3000N; plates=1000-1500N
• Haynes Med Eng Phys 1997
– Cadaveric study
– SGN=5761N; DHS=4660N(hard) 3225N(soft)
• Aune Acta Orth Scan 1994 & Madsen J Ortho Res 1998
– Femoral shaft fractures with SGN
• Parker & Handoll Cochrane Rev 2004, 2008, 2009
– Better intraoperative results and less fixation failures in
cephalomedullary devices
– Femoral shaft fractures with short nails

29. • Infection
• VTE
• Implant failure
– Varus malreduction
– Screw placement in femoral head
• Malunion
– Shortening
– Rotational deformity
– Varus
• Nonunion ( 0-8%)
– Significant pain >6 months with the inability to FWB
– Stable fixation - autogenous bone grafting
– Exchange nailing with over-reaming

30. • Fletcher AK et al. Three-in-One Femoral Nerve
Block as Analgesia for Fractured Neck of
Femur in the Emergency Department: A
Randomized, Controlled Trial. Ann Emerg
Med. 2003;41:227-233
• Craig N et al. Subtrochanteric fractures. Bull
Hosp Joint Dis 2001;60:35-46
• Lundy DW. Subtrochanteric femoral fractures.
AAOS 2007;15:663-671

31. 1. Kloen P et al. Subtrochanteric fracture after
cannulated screw fixation of femoral neck
fractures: a report of four cases. J Orthop
Trauma. 2003;17(3):225-9
2. Lichtblau S et al. A biomechanical
comparison of two patterns of screw
insertion. Bull NYU Hosp Jt Dis.
2008;66(4):269-71

32. 1. Goh et al. Subtrochanteric insufficiency fractures in
patients on alendronate therapy. JBJS 89-B(3); 349-
353
2. Lenart et al. Atypical Fractures of the Femoral
Diaphysis in Postmenopausal Women Taking
Alendronate. NEJM 2008 358;12:1304-6
3. Neviaser et al. Low-Energy Femoral Shaft Fractures
Associated With Alendronate Use. J Orth Trauma
2008; 22(5): 346-350
4. Kweka et al. An emerging pattern of subtrochanteric
stress fractures: A long-term complication of
alendronate therapy. Injury 2008 39; 224—231