INCIDENCE OF INTERNAL
DERANGEMENTS OF KNEE WITH
IPSILATERAL FEMORAL SHAFT
FRACTURE
ABSTRACT NUMBER : 120
INTRODUCTION
 Diaphyseal femur fractures are mostly the result of high energy
trauma .
 Femoral shaft fractures are often associated with bony and soft
tissue injuries to the ipsilateral knee, and a high index of
suspicion is necessary to identify these lesions.
 These ligament injuries are usually silent or occult and many of
them progress undiagnosed at this stage, with negative
consequences for patients and orthopedicians.
 Assessment of the ligaments of the knee by clinical examination
in the emergency room is difficult to perform as the distal
segment of the fractured femur is unstable; and movement of
the affected knee may cause more pain or discomfort to the
patient.
 The clinical methods to assess the knee joint for intraarticular
soft tissue injuries are either under anesthesia preoperatively or
after fixation postoperatively.
 The
disadvantage
of
examination
under
anesthesia
preoperatively is meniscal injuries cannot be assessed optimally.
 Hence we hypothesised that a preoperative MRI of the affected
knee joint, will aid in the diagnosis of a soft tissue injury.
OBJECTIVES
 To anticipate meniscal, ligamentous and retinacular injuries of the knee in
patients sustaining ipsilateral femoral shaft fractures.
 To identify the type and character of intraarticular ligamentous injuries of
the knee joint following ipsilateral femoral shaft fractures.
 To emphasize the need for an MRI of the knee with ipsilateral femoral shaft
fractures in the preoperative period.
 To establish the advantages of MRI knee in tailoring the management
strategy of femoral shaft fracture and to address the issue of intraarticular
soft tissue injuries.
METHODOLOGY
STEP 1
• Patients with femoral shaft of femur fracture
• Patients fulfilling the inclusion criteria and exclusion
criteria were selected
STEP 2
• Patient explained about the advantage of the
investigation
• Written consent was obtained
STEP 3
• MRI of ipsilateral knee was done and findings were noted
• All findings were tabulated in a master sheet and
incidence was calculated.
Methodology
INCLUSION CRITERIA :
1) Age group: >15 years.
2) Patients with fracture shaft of femur.
EXCLUSION CRITERIA:
1) Patients with periprosthetic, pathologic fractures or
polytrauma.
2) All patients with previous knee injuries or previous knee
surgery.
3) Patients on cardiac pace makers or metal implants.
4) Any other contraindications for an MRI.
RESULTS
 Out of 40 patients, there was incidence of intraarticular
soft tissue injuries in 26 patients (65%) .
Injury
Number of Cases
Anterior cruciate ligament
Complete tear
Partial tear
Total ACL
8 (20%)
5 (12.5%)
13 (32.5%)
Posterior cruciate ligament
Complete avulsion
Complete tear
Partial tear
Total PCL
2 (5%)
2 (5%)
5 (12.5%)
9 (22.5%)
Medial collateral ligament (MCL)
Complete tear
Partial tear
Lateral collateral ligament (LCL)
Complete tear
Partial tear
Menisci
Medial
Anterior horn
Posterior horn
Lateral
Anterior horn
Posterior horn
Total menisci
10 (25%)
1 (2.5%)
5 (2.5%)
6 (15%)
2 (5%)
2 (5%)
16 (40%)
Extensor mechanism
Patellar tendon partial tear
Patellar tendon complete tear
Quadriceps tendon partial tear
Total extensor mechanism
1 (2.5%)
1 (2.5%)
2 (5%)
4 (10%)
Retinacular tears
Cartilage
Bone
Contusion
Occult fracture
4 (10%)
2 (5%)
2 (5%)
4 (10%)
2 (5%)
2 (5%)
3 (7.5%)
0 (0%)
32 (80%)
3 (7.5%)
NUMBER OF CASES
PERCENTAGE
Effusion
40 / 40
100 %
Bone contusions
32 / 40
80 %
ACL injury
13 / 40
32 %
PCL injury
9 / 40
22 %
MCL injury
4 / 40
10 %
LCL injury
4 / 40
10 %
Medial meniscus injury
10 / 40
25 %
Lateral meniscus injury
6 / 40
15 %
Capsular tears
3 / 40
8%
Patellar tendon injury
2 / 40
5%
STRUCTURE INVOLVED
NUMBER OF CASES
PERCENTAGE
ACL
4
10 %
PCL
4
10 %
LCL
1
2.5 %
MCL
3
7.5 %
MM
2
5%
LM
1
2.5 %
MM + LM
1
2.5 %
ACL + PCL
2
5%
ACL + MM
2
5%
ACL + PCL + MM
1
2.5 %
ACL + PCL +LCL + MM + LM
1
2.5 %
PCL + LCL + MM
1
2.5 %
ACL + PCL + LM
1
2.5 %
ACL + LCL + MM + LM
1
2.5 %
ACL + MM + LM
1
2.5 %
No ligamental or meniscal injury
14
35 %
TOTAL NUMBER OF CASES
40
100 %
ACL
PCL
LCL
MCL
MM
LM
MM + LM
ACL + PCL
ACL + MM
ACL + PCL + MM
ACL + PCL +LCL + MM + LM
PCL + LCL + MM
ACL + PCL + LM
ACL + LCL + MM + LM
De Campos 1994
Blacksin 1998
Dickson 2002
Our study 2014
(Arthroscopy)
(MRI)
(MRI)
(MRI)
Number of
patients
Total abnormal
40
34
27
40
22 (55%)
34 (100%)+
19 (70%)
26 (65%)
ACL
21 (53%)
2 (6%)
5 (19%)
13 (32.5%)
PCL
3 (7.5%)
7 (21%)
2 (7%)
9 (22.5 %)
LCL
5 (12.5%)
2 (6%)
8 (30%)
4 (10%)
MCL
11 (27.5%)
13 (38%)
11 (41%)
4 (10%)
Total meniscus
13 (32%) knees
10 (30%)
11 (41%)
16 (40%)
Lateral meniscus
8 (20%)
4 (12%)
7 (26%)
6 (15%)
Medial meniscus
5 (12%)
6 (18%)
4 (15%)
10 (25%)
Bone bruise
N/A
32%
25 (93%)
32 (80%)
N/A
40 (100%)
1 (3%) occult tibial
plateau fracture
Effusion
N/A
33 (97%)
Why a pre-operative MRI?
Why not post-operative MRI?
 In order to reduce the error factors addressed in the
previous studies like iatrogenic MCL tears during
interlocking screw fixation,
 MRI of patients with stainless steel induced artifacts in
retrograde intramedullary nailing were excluded in the
previous study, which may have caused variation in the
true incidence of internal derangements of the knee.
Antero – Lateral ligament (ALL)
ALL injury in MRI
Proximal ALL injury
Distal ALL injury
Incidence of ALL injury in our study
Incidence – 11 cases (44%)
 Proximal ALL injury
 Distal ALL injury
 Proximal + Distal ALL injury
– 4 cases (16%)
– 5 cases (20%)
– 2 cases (8%)
Conclusion
 Femoral shaft fractures exerted by high velocity forces have been proven to
cause internal derangements in the ipsilateral knee along with soft tissue
injuries, by exhaustive analysis by various orthopedists, radiologists through
physical examination, X-rays analysis, MR imaging and arthroscopic
evaluation.
 The incidence of internal derangements of the knee in our study using MRI
is similar to those reported in the previous studies using arthroscopy and/or
MRI as diagnostic tools.
MR imaging of the knee is considered advantageous to have shown
 a significant increase in the incidence of ligamentous injuries in
the knee from 5% in earlier studies to 70% in recent studies;
 in the identification of clinically suspected meniscal injuries
through a non-invasive approach;
 and a suitable non- radiational imaging modality for arthroscopic
blind spots.
Take home message
 In a case of femoral shaft fracture due to a high velocity trauma, the
attending surgeon must beware of an internal derangement of the
knee and must investigate for knee instability, ligament laxity.
 Currently there is no general consensus on the use of the MRI scan
as a standard diagnostic preoperative tool. It is usually preserved
for patients who develop joint instability or soft tissue related
symptoms(knee locking, persistent joint pain) at a secondary stage
following fracture healing and weight bearing.