Nailing it hip fractures short versus long; locked versus non locked
1. SRI SIDDHARTHA MEDICAL COLLEGE,TUMKUR
Department of orthopaedics
Topic:
Nailing Intertrochanteric Hip Fractures:
Short versus long; locked versus nonlocked
⢠Moderator:
Dr. J.K Reddy
Prof. & HOD
Dept. Of
Orthopaedics
⢠Presenter:
Dr. Jaipalsinh
Mahida
Resident
Dept. Of
Orthopaedics
2. introduction
⢠Occurs in the region between greater & lesser trochanters of the femur;
often extending to the subtrochanteric region.
⢠Extracapsular
⢠Higher incidence between elderly population
⢠Large number of implants developed
ďźsince 50s - compression/ sliding hip screw
ď§ SHS- Gold standard of extramedullary device
ďźIn 80s - intramedullary devices
3. ⢠Intramedullary nails represented from
ďźShort & long nails entering from area of greater trochanter
ďźVarious diameter
ďźAnteversion angles
ďźProximal configuration as far as shape, size & number of lag screws
ďźShaft & distal end vary in
ď§ Radius of curvature
ď§ Width
ď§ Shape of nail tip
ď§ Number, location & method of insertion/ guidance of distal locking screw.
4. ⢠Type 33.A3 or unstable Fracture
ďźBest treated with intramedullary device
⢠For stable fractures
ďźSHS shows fewer complication rates & no worse functional outcome compared to
intramedullary nail
ďźClinical study do not match biomechanical data suggesting superiority of long distally
locked cephalomedullary nail over SHS for management of stable fractures
⢠Use of cephalomedullary nails has increased in last 15 years from 3% to 67%
in USA & Europe
ďźShift is more impressive between younger generation of surgeons
ďźHas interesting geographic variations
ďźFollows introduction of 3rd & 4th generation nails
5. ⢠However, contemporary understanding of advantages of IM nailing of
extracapsular hip fractures dictates their use for unstable fractures, that
is, those with reverse obliquity, with posteromedial comminution,
compromised of fracrured lateral wall & clearly those with
subtrochanteric extension.
⢠This article attempts to summarize
ďźContemporary understanding of excisting biomechanical & clinical evidence of IM
nailing of IT fractures, as to weather they should be short or long nails spanning
the whole length of femur, & use or not of distal locking screws.
6. Anatomy
⢠IT fractures occur in the region between GT & LT of proximal femur,
occasionally extending into subtrochanteric region
⢠These extracapsular fractures occur in cancellous bone with abundant blood
supply. As a result nonunion & osteonecrosis are not major problems, as in
femoral neck fractures
⢠Deforming muscle forces will usually produce Shortening, External rotation &
Varus position at fracture site
ďźAbductors tend to displace GT laterally & proximally
ďźIliopsoas displace LT medially & proximally
ďźHip flexors, extensors & adductors pull distal fragment proximally
⢠Fracture stability is determined by presence of posteromedial bony contact,
which act as a buttress against fracture collapse
7.
8. Mechanism of injury
⢠Most fractures results from direct impact to GT area
⢠Younger individuals:
ďźHigh energy injury such as motor vehicle accident or fall from height
ď§ More common in men less than 40 years
⢠90% of IT fractures in elderly results from a simple fall(higher in
women)
⢠Tendency to fall increases with patient age, poor vision,
decreased muscle power, labile blood pressure, decreased
reflexes, vascular disease & coexisting musculoskeletal pathology
9. Cummingâs factors determining fracture at hip
⢠The faller must be orientd to fall or âimpactâ near hip
⢠Local soft tissue must absorb less energy than necessary to
prevent fracture(inadequate soft tissue- muscle/ fat coverage)
⢠Protective responses must be inadequate to reduce the energy of
fall beyond a certain critical threshold
⢠Residual energy of fall applied to proximal femur must exceed its
strength(i.e: bone strength at hip must be insufficient)
10. Imaging studies- x-rays
⢠Pelvis with both hip- AP view
⢠X-ray of affected hip- AP & cross-table lateral
⢠Traction films (with internal rotation) â helpful in communited and
high â energy fractures and in determining implant selection
⢠For subtrochanteric extension â femur AP & lateral view
11.
12.
13. Diagnosis and classification
⢠Increased surgical complexity & recovery are associated with
UNSTABLE FRACTURE pattern
ďźPosteromedial large separate fragmentation
ďźBasicervical pattern
ďźReverse obliquity patterns
ďźDisplaced greater trochanteric(lateral wall fracture)
ďźFailure to reduce the fracture before internal fixation
14. Classification systems
⢠No single classification system that has achieved reliable reproductive
validity
⢠1822- sir Astley Cooper (london) described the 1st (pre- radiographic)
classification of hip fracture
ďźIntra capsular ( main complication- non- union)
ďźExtracapsular (main complication â coxa vara)
15. Boyd & griffin classification
⢠Type I : Fractures that extend along the intertrochanteric line
⢠Type II : Comminuted fractures with main fracture line along
intertrochanteric line but with multiple secondary fracture lines
⢠Type III: Fractures that extend to or are distal to the lesser trochanter
⢠Type IV: fractures of the trochanteric region & proximal shaft with
fractures in at least 2 planes
⢠Type III & IV are most difficult types to manage
ďźAccounts for 1/3rd of trochanteric fractures
16.
17. Evanâs classification:
⢠Based on prereduction & postreduction stability, that is, the
convertibility of an unstable fracture configuration to a stable
reduction
⢠In stable fracture patterns , posteromedial cortex remains intact or
has minimal comminution, making it possible to obtain & maintain a
stable reduction
⢠Unstable fracture patterns are characterized by greater comminution
of posteromedial cortex
ďźThough inherently unstable, these fractures can be converted to a stable
reduction if medial cortical opposition is obtained
⢠Reverse obliquity pattern is inherently unstable because the tendency
for medial displacement of femoral shaft
18.
19. Ota/ao classification
⢠Most quoted in recent scientific articles- a derivative of muller
classification
⢠Has been very useful in evaluating results of treatment of IT fracture
& allowing comparisons among reports in literature.
⢠Group 1 fractures (31 A1): fractures are not comminuted
ďźPertrochanteric simple((2-part) fractures with typical oblique fracture line
extending from GT to medial cortex, lateral cortex of GT remains intact
ďź A1.1 â along IT line
ďźA1.2 â through GT
ďźA1.3 â below LT
20.
21. ⢠Group 2 fractures (31 A2): fractures have increasing comminuation.
ďźPertrochanteric multifragmentary â comminuted fractures with posteromedial
fragment, lateral cortex of GT however remains intact. fractures are unstable,
depending on size of medial fragment
ďźA2.1 â with one intermediate fragment
ďźA2.2 â with several intermediate fragments
ďźA2.3 â extending more than 1 cm below lesser trochanter
22. ⢠Group 3 fractures (31 A3): fractures includes reverse obliquity or
subtrochanteric extension
ďźTrue IT- are those in which fracture line extends across both medial &
lateral cortices; also includes reverse obliquity
ďź A3.1 â simple oblique
ďźA3.2 â simple transverse
ďźA3.3 â multifragmentary
23. Unusual fracture pattern
⢠BASICERVICAL FRACTURES:
⢠Located proximal to or along IT line
⢠Although anatomically femoral neck fracture, they are usually
extracapsular and behave like IT fractures
⢠At greater risk for osteonecrosis when compared to more distal IT
fractures
⢠Lack cancellous intertrochanteric region & are more likely to sustain
rotation of the femoral head
24.
25. Unusual fracture pattern
⢠REVERSE OBLIQUITY:
⢠Oblique fracture line extending from medial cortex proximally to lateral
cortex distally
⢠Tendency to medial displacement due to pull of adductor muscles
⢠Should be treated as subtrochanteric fractures
26.
27. treatment
1. Non operative:
ďźIndicated only for patients who are at extreme medical risk for surgery; it may
be considered for demented nonambukatory patients with mild hip pain
ďźNondisplaced fractures can be considered for non operative treatment
ďźEarly bed to chair mobilization is important to avoid increased risks &
complications of prolonged recumbency, including poor pulmonary toilet,
atelectasis, venous stasis, & pressure ulcerations
ďźResultant hip deformity is both expected & accepted in cases of displacements
28. ⢠Prolonged bed rest in traction until fracture unites( 10 â 12 weeks)
ďźBuckâs traction
ďźRussell skeletal traction
ďźBalanced traction in Thomas splint
ďźPlaster spica immobilization
ďźDerotation boot
29. ⢠Complications of non-operative treatment:
ďźUTI
ďźKnee stiffness
ďźPneumonia
ďźThromboembolic complications â resulting in high mortality rate
ďźFracture healing is accompanied by malunion & nonunion , varus deformity
& shortening
30. 2. Operative:
ďźGoal is stable internal fixation to allow early mobilization & full weight
bearing ambulation.
ďźStability of fracture fixation depends on
ď§ Bone quality
ď§ Fracture pattern
ď§ Fracture reduction
ď§ Implant design
ď§ Implant placement
32. Advantages of cephalomedullary nails:
⢠Because of its location theoretically it provides more efficient
load transfer than does a sliding hip screw
⢠Shorter lever arm of IM device can be expected to decrease
tensile strain on implant, thereby decreasing risk of implant
failure
⢠Because IM fixation device incorporates a sliding hip screw,
advantage of controlled fracture impaction is maintained
⢠Shorter operative time & less soft tissue dissection than sliding
hip screw
33. Proximal femoral nail
⢠Shown to prevent fractures of femoral shaft by having a smaller distal
shaft diameter which reduces stress concentration at the tip
⢠Due to its position close to weight-bearing axis stress generated on IM
implant Is negligible
⢠It also acts as a buttress in preventing medicalization of the shaft. Entry
portal of PFN through trochanter limits surgical insult to tendinous hip
abductor musculature only, unlike those nails which require entry
through piriformis fossa
⢠Total length: - standard nail- 240 mm
- short nail- 200 mm
34. Short versus long nails
⢠Intertrochanteric Intramedullary nailing in general
ďź is an antegrade insertion of femoral nail with wider proximal part & proximal slot
which allows a single or couple of lag screws/or a blade to be inserted from lateral
cortex of femur, passing through nail slot/s, across femoral neck, finishing at
subchondral area of femoral head.
ďźInitially nail length was short- finishing above level of isthemus
ďźAfter 1980s- long version nail spanning whole length of femoral shaft & ending at
supracondylar region was introduced
35. ⢠Number of authors suggests
ďźLong nail less likely to refracture than short
ďźProvides more stable construct
⢠Review study of Norris et al:
ďźIncluded 13,568 IT fractures from 89 studies
ďźAdvantage of long nail didnât reach statistical significance(1.1% V/s 1.7%)
ďźBut, Described improvement of performance of modern long nails Vs previous
design.
36.
37. ⢠Okcu et al :
ďźStudy was underpowered & had short follow-up
ďźConclusion:
ď§ Reverse oblique fractures can be treated effectively with either short or long nails
⢠Hou et al:
ďźExcluded reverse oblique & fracture with subtrochanteric extension
ďź conclusion:
ď§ No clear benefit of elderly patients is offered by using a long nail in simple &
multifragmentary IT fractures
38. ⢠Kleweno et al :
ďźLargest series in current orthopaedic literature comparing short Vs long nails
ďźIncluded all types of IT fractures
ďźUsed 4 nail types
ďź20% patients lost to follow-up
ďźObservation:
ď§ Similar rate of periprosthetic fracture & reoperative rates
o Reason for reoperation- cutout of head/neck component
ďźConclusion:
ď§ no difference of failure rates with long and short nails
39. ⢠Vaughn et al :
ďźConclusion:
ď§ Similar results in catastrophic failures (periprosthetic fractures, proximal
fixation failure, AVN femoral head) should be anticipated with both nails
ď§ More minor complications ( prominent lag or interlocking screw) reported
with long nails
40. ⢠In general and until any future contradicting evidence, long nails
are preferable when longer working length is needed, i.e in
comminuted fractures with subtrochanteric extension, or when
protection of whole femoral shaft is necessary, i.e severe
osteoporosis, known metastatic lesions, or suspected femoral
pathology.
41. locked versus unlocked nails
⢠Use of long or short nail with or without distal interlocking fixation
has been recommended for both stable and unstable IT fractures
⢠IM nails bear most weight initially, & gradually transfers to bone as
fracture healing progresses
⢠Load bearing of IM nail is largely dependent on fracture pattern and
reduction achieved
⢠Reaming and distal locking allows transmission of physiological load to
proximal & distal end of nail threw screws
42. ⢠In absence on interlocking screws
ďźImplant transfer axial compaction motion along longitudinal axis of nail to bone
⢠With significant cortical contact, compressive loads will be supported in
largely by bone cortices
⢠Without cortical contact, all compressive loads will be transferred
distally through nail to distal interlocking screws, which resist fracture
collapse and length loss until their fatigue failure or fracture healing
⢠For axial &/or rotationally unstable fractures
ďźDistal locking screws maintains fracture length, prevent limb shortening &
subsequently increase fracture stability and allow early mobilization
43.
44. ⢠Roseblum et al:
ďź1800 N axial load in static locked or in unlocked mode
ďźDynamic loading & common rotational forces conditions not accounted in study
⢠Kane et al:
ďźAssessed rotational stiffness in stable IT fracture model
ďźLocked nails provided statically stiffer construct than unlocked
ďźAuthor suggested
ď§ Locked distal construct may fatigue & break earlier when subjected to
torsional loading
45. ⢠Problems with distal locking screws:
ďźActs as stress raiser causing subsequent implant breakage
ďźsoft tissue irritation
ďźdistal femoral condyle fractures
⢠Currently distal locking is dictated in IT fractures with either sever
comminution or subtrochanteric distal extension or in gross osteopenia
& ballooning of femoral diaphysis, to avoid painful toggling of nail into
diaphyseal canal at early stage & malunion in form of loss of femoral
length, malalignment & rotational deformity.
46. discussion
⢠Phyiological loading of nail-bone construct of IT fracture treated with
IM nail comprises of 3 forces:
1. Torsion
2. Compression of medial aspect of nail
3. Tension on lateral aspect
⢠Load bearing of IM nail largely depends on fracture pattern & achieved
reduction
⢠When Cortical contact across fracture site achieved
ďźLarge portion of compressive load is supported by cortices
⢠In Absence of cortical contact
ďźCompressive & rotational loads are transmitted distally through nail to distal
locking screws.
47. ⢠Ist generation of short cephalomedullary nails
ďźAssociated with unacceptable high rates (5%-23%) of perioperative
periprosthetic fractures, attributed to
ď§ Nail jamming& abutment to posterolateral cortex
ď§ High proximal nail valgus angle
ď§ Excessively large distal diameters
ď§ Inherent high material stiffness
ď§ Poor canal preparation & distal interlocking insertion techniques
⢠use of long cephalomedullary nail was adopted
ďźTo avoid above mentioned complications
ďźBenefit of spanning whole femur
ďźPreventing future periprosthetic fractures
48. ⢠Use of long cephalomedullary nails was challenging in stable subtype IT
fractures
ďźIncreased blood loss after reaming
ďźElongation of operative time
ďźIncreased radiation exposure for distal interlocking screw
ďźEffective distal targeting
ďźAnterior encroachment of nail at supracondylar region
49. ⢠Improved characteristics of newer generation short & long nails
ďźFlexibility of material
ďźReplication of specific anatomic characteristic of femur
ď§ Radius of curvature
ď§ Version & size of proximal femur
ď§ Neck shaft angle
ďźTapered stems & smaller locking screws
50. ⢠No high level clinical evidence exist to reach safe conclusion regarding
optimal use of cephalomedullary nails over sliding hip screw, at least for
stable IT fractures
⢠Comparison of clinical end point between studies using nails of different
generations, designs, characteristics of existing meta-analysis remains
frustrating inconclusive.
⢠Author believes that for unstable or reverse oblique fractures, there is
no adequate evidence to support any deviation from current practice,
which is consistent with use of long statically locked nails.
⢠More studies required
Working length: actual portion of nail between proximal & distal point of fixation to bone. Longer the distance, greater the flexion of nail. Transverse fracture require a much shorter working length than comminuted.