This document contains information about a patient presenting with a right patellar fracture. The 44-year-old male patient reported right knee pain for 5 hours after falling from his motorcycle while intoxicated on dirt roads. On examination, he had a 2cm laceration on his right knee with active bleeding and inability to flex or extend the right knee. X-rays confirmed an open right patellar fracture. The patient was given IV antibiotics and pain medications. He was taken to the OR for debridement and cerclage wiring of the patellar fracture.

1. EXTERN CONFERENCE Warot Srirueanthong

2. PATIENT PROFILE
Case ชายไทยคู่ อายุ 44 ปี
CC: ปวดเข่าขวามา 5 ชั่วโมง ก่อนมาโรงพยาบาล
PI: 5 ชั่วโมง ก่อนมาโรงพยาบาล ผู้ป่วยดื่มเหล้าเมา ขับรถจักรยานล้มเอง บริเวณที่ล้มเป็นถนนมีดิน
สกปรก ไม่สลบ ไม่มีศรีษะกระแทก มีแผลฉีกขาดที่หัวเข่าด้านขวาและเลือดออกจากแผล ขยับงอ/
เหยียดเข่าขวาไม่ได้ ไม่มีอาการปวดบริเวณอื่น

3. PRIMARY SURVEY
A: can speak, can flex neck, no tender along c-spine
B: no neck vein engorge, symmetrical chest movement, trachea in
midline, no subcutaneous emphysema, clear and equal both lungs, CCT
negative
C: cap refill < 2 sec, BP 126/75 mmHg, PR 70 bpm, DPA Rt 2+
D: E4V5M6 pupils 3 mm RTLBE, no lateralization sign
E: laceration wound 2 cm at Rt knee with active bleed

4. LACERATION WOUND 2 CM AT RT KNEE
WITH ACTIVE BLEED

5. SECONDARY SURVEY
A: no Hx of drug/food allergy
M: no current medication
P: no underlying disease
L: NPO time 15.00 (6 hr)
E: as present illness

6. PHYSICAL EXAMINATION
Airway and Breathing: spontaneous breathing
Vital signs: BP 126/75 mmHg, PR 70 bpm, RR 12/min, T 37
HEENT: not pale conjunctiva, anicteric sclera, no external wound
C-spine: no posterior midline neck pain, no soft tissue contusion or
swelling around the neck
Chest: clear and equal both lungs
CVS: normal S1 S2, no murmur
Abdomen: soft, not tender

7. PHYSICAL EXAMINATION
Extremities: laceration wound 2 cm at Rt knee with active bleed, Rt
knee no deformities, stepping at patellar, limit both flexion and
extension, normal pinprick sensation, DPA Rt 2+, PTA Rt 2+
Neuro: E4V5M6 pupils 3 mm RTLBE, motor Gr V all

8. INVESTIGATION: FILM RT KNEE AP, LAT

9. DIAGNOSIS
Open fracture Rt patellar

10. MANAGEMENT
Initial management:
- Lab pre-op:
CBC, BUN, Cr, Electrolyte, anti HIV, LFT, Coagulogram, CXR,
EKG 12 leads
- Pain control & Prevent N/V:
MO 4 mg IV q 6 hr
Plasil 10 mg IV q 6 hr
- ATB:
Cefazolin 1g IV q 6 hr
Gentamicin 240 mg IV OD x 3 days
- Thiamine 100 mg IV OD x 3 days
Definite treatment: Set OR for debridement with cerclage wiring

11. PATELLAR FRACTURE Warot Srirueanthong

12. PATELLAR FRACTURE
•1% of all skeletal fracture
•1% of these occur in the immature skeleton, so fractures of the patella
in children are rare

13. MECHANISM OF INJURY
•Direct >> direct blow (low energy and high energy)
• High energy >> comminuted fracture pattern, ! associated injuries
of ipsilateral limb, including hip dislocation, proximal femur
fractures, or fractures about the knee
•Indirect >> secondary to the large forces generated through the
extensor mechanism
• Typically result from forceful contraction of the quadriceps with the
knee in a flexed position
• Indirect injuries frequently cause a greater degree of retinacular
disruption compared with direct injuries >> active knee extension
is compromised
• Transverse fracture patterns
•Combined

14. ASSOCIATED INJURIES
•Most often, associated injuries occur in the ipsilateral lower extremities
•Ipsilateral distal femur or proximal tibia fracture
•Extensor mechanism injury

15. HISTORY
•Direct blow to the patella
•Fall from a standing height
•Near fall with forceful contraction of the quadriceps on a partially
flexed knee
•Anterior knee pain
•Swelling
•Difficult to ambulating after a fall are also common and may
reflect an injury to extensor mechanism

16. PHYSICAL EXAMINATION
•Displaced patella fractures >> acute hemarthrosis, tender and
palpable defect between the fracture fragments
•The absence of a large effusion in the presence of a palpable bony
defect should raise concern for associated retinacular tears
•Extensor mechanism
“however, that the patient’s ability to extend the knee dose not rule out a
patella fracture, but rather it suggests that the continuity of the extensor
mechanism is maintained via an intact retinacular sleeve”

17. PHYSICAL EXAMINATION
•Laceration or abrasion to the skin overlying the patella are particular
concern, and may reflect an occult open fracture or communication
with the knee joint >> Saline loading test
18-gauge needle and syringe >
joint aspiration > infusion of 150
mL of saline
“! Communication between
knee joint and wound is
marked by egress of the
infused saline from the
wound”

18. INVESTIGATION
•Plain radiograph: AP, Lat, Tangential or axial view of patellofemoral joint
•CT
• Rarely necessary in the evaluation and treatment of isolated patellar
fractures
•MRI
• evaluate suspected extensor mechanism injuries
• chondral injuries associated with patellar dislocations

19. PLAIN RADIOGRAPH: AP, LAT, TANGENTIAL
OR AXIAL VIEW OF PATELLOFEMORAL JOINT

21. BIPARTITE OR TRIPARTITE PATELLA
•Can often be mistaken for a
fracture in the setting of
trauma
•Anatomical variants reflect
incomplete fusion of two or
more ossification centers
•The opposing edges are
usually smooth and corticated
on plain radiographs
•Typically bilateral, and
contralateral knee
radiographs often confirm the
diagnosis The most common bipartite pattern is located in the superolateral
aspect of the patella and is not associated with any pain, tenderness,
or functional compromise of the extensor mech

22. CLASSIFICATION OF PATELLAR
FRACTURES
•Displaced or nondisplaced
•Categorized on the basis of the geometric configuration of fracture
lines

23. DISPLACED
•Defined by separation of fracture fragments by > 3 mm or articular
incongruity > 2 mm

24. CATEGORIZED ON THE BASIS OF THE GEOMETRIC
CONFIGURATION OF FRACTURE LINES

25. TREATMENT OPTIONS
•Nonoperative vs Operative

26. NONOPERATIVE
•Typically consists of 4-6 wk
•Knee immobilized in extension (brace or cylinder
cast) and full weight bearing
•indications
• intact extensor mechanism (patient able to perform
straight leg raise)
• nondisplaced or minimally displaced fractures
• vertical fracture patterns
•early active ROM with hinged knee brace
• early WBAT in full extension
• progress in flexion after 2-3 weeks

27. OPERATIVE
ORIF with tension band
construct
Indications
• preserve patella whenever
possible
• extensor mechanism failure (unable
to perform straight leg raise)
• open fractures
• fracture articular displacement
>2mm
• displaced patella fracture >3mm
• patella sleeve fractures in children
Partial patellectomy
Indications
• comminuted superior or inferior
pole fracture measuring <50%
patellar height ONLY if ORIF is not
possible
Total patellectomy
Indications
• reserved for severe and extensive
comminution not amenable to
salvage
• quadriceps torque reduced by
50%
• medial and lateral retinacular
repair essential

28. COMPLICATIONS
•Weakness and anterior knee pain
•Symptomatic hardware (up to 50%) most common
•Loss of reduction (22%) increased in osteoporotic bone
•Nonunion (<5%) can consider partial patellectomy
•Osteonecrosis (proximal fragment)
• thought to be due to excessive initial fracture displacement
• can observe these, as most spontaneously revascularize by 2 years
•Infection
•Stiffness

29. GUSTILO CLASSIFICATION Warot Srirueanthong

30. Gustilo Type I II IIIA IIIB IIIC
Energy Low Moderate High High High
Wound Size ≤ 1 cm 1-10 cm usually >10 cm usually >10 cm usually >10 cm
Soft Tissue Damage Minimal Moderate Extensive Extensive Extensive
Contamination Clean Moderate
contamination
Extensive Extensive Extensive
Fracture Pattern Simple fx pattern
with minimal
comminution
Moderate
comminution
Severe
comminution or
segmental
fractures
Severe
comminution or
segmental
fractures
Severe
comminution or
segmental
fractures
Periosteal Stripping No No Yes Yes Yes
Skin Coverage Local coverage Local coverage Local coverage Requires free
tissue flap or
rotational flap
coverage
Typically requires
flap coverage
Neurovascular
Injury Normal Normal Normal Normal
Exposed fracture
with arterial
damage that
requires repair
Antibiotics 1st generation cephalosporin (e.g.
cefazolin) for 24 hours after closure
1st generation cephalosporin for gram positive coverage.
Aminoglycoside (such as gentamicin) for gram negative
coverage in type III injuries
the cephalosporin/aminoglycoside should be continued
for 24-72 hours after the last debridement procedure
Penicillin should be added if concern for anaerobic organism
(farm injury)

31. ANTIBIOTICS (OTHER CONSIDERATIONS)
FOR ALL TYPES
•Flouroquinolones (e.g. ciprofloxacin)
• should be used for fresh water wounds or salt water wounds
• can be used if allergic to cephalosporins or clindamycin
•Doxycycline and 3rd or 4th-generation
cephalosporin(e.g. ceftazidime)
• can be used for salt water wounds

32. ANTIBIOTIC INDICATIONS FOR OPEN
FRACTURES
Gustillo Grade I and II
1st generation cephalosporin
Gustillo Grade III
1st generation cephalosporin + aminoglycoside
traditionally recommended, but there is controversy about this regimen
With farm injury / bowel contamination
1st generation cephalosporin + aminoglycoside + PCN
add PCN for clostridia
Duration
initiate as soon as possible
increased infection rate when antibiotics are delayed > 3 hours from time of
injury
continue for 24-72 hours after I&D
Tetanus booster if not up to date (no booster in last 5 years)

33. REFERENCES
Rockwood and Green’s Fractures in Adults 8th ed
Campbell’s operative orthopaedics 13th ed
https://www.orthobullets.com/trauma/1042/patella-fracture

34. THANK YOU