Knee & Lower Leg Injuries

Dr. Muhammad Salman

Knee Anatomy:

Knee Examination

History: ask about current mechanism of injury, prior injuries or surgeries to knee.

Inspect: pt. should be examined while walking, note gait, muscular development, functional ROM. – Inspect the knee for swelling, ecchymosis,

effusion, masses, patella location, erythema, signs of local trauma, note leg lengths, active range of motion.

Knee Examination

Check for neurovascular status Palpate the knee, patella, medial and lateral

joint lines Place the knee in various stress testing

Patella Fractures

Result from direct blow such as knee hitting dashboard in MVA, fall on flexed knee, forceful contraction of quad. Muscle.

Transverse fractures most common PE: focal patellar tenderness, swelling,

effusion. – Check for extensor mechanism by doing straight

leg raising against gravity.

Patella Fracture:

Patella Fracture:

Patella Fracture

Tx: non-displaced patella fracture w/intact extensor mechanism is treated w/knee immobilizer, rest, ice , elevation, NSAIDS/Opioids, then long leg cast for 6 weeks.– Fractures that are displaced > 3 mm or assoc.

w/disruption of extensor mechanism requires Ortho. Referral for open reduction & internal fixation

Femoral Condyle Fractures

These injuries secondary to direct trauma from fall w/axial loading or blow to distal femur.

Exam reveals pain, swelling, deformity, rotation, shortening and inability to ambulate

Potential for popliteal artery injury, check for ipsilateral hip dislocations or fractures

Femoral Condyle Fracture:

Femoral Condyle Fractures

Cast immobilization for stable, non- displaced fractures

Open reduction internal fixation for displaced fractures or any degree of joint incongruity

Complications: DVT, fat embolus, delay or malunion, development of OA

Tibial Spine & Tuberosity Fractures

Tibial spine Fx’s:– Anterior tibial spine more commonly fractured– Painful swollen knee, inability to extend fully– If fracture is incomplete or non- displaced, it

should be immobilized in full extension w/knee immobilizer.

– Complete, displaced fractures require open reduction internal fixation (ORIF)

Tibial Spine Fracture:

Tibial Spine & Tuberosity

Tibial tuberosity: quadriceps mechanism inserts on tibial tubercle– Sudden force to flexed knee w/quadriceps

contraction may avulse tibial tubercle– If avulsion is small or non- displaced just

immobilize.– If displaced, needs ORIF

Tibial Tuberosity Avulsion Fx:

Tibial Plateau Fractures

Produced by varus or valgus forces combined w/axial loading which drives femoral condyles into tibial plateau– Examples: fall from a height or leg struck by car– Painful swelling of knee, limited ROM,

ligamentous instability

Lateral Tibial Platea Fx:

Tibial Plateau Fractures

If one plateau is fractured but non- displaced, Tx w/knee immobilizer, non-weight bearing, outpt. Ortho follow-up for long leg cast

Complications: popliteal artery injury, DVT, OA

Knee Ligaments:

Knee Dislocation:

Result of ligamentous disruption, posterior dislocation is most common

With posterior dislocation, ACL & PCL injuries/disruption are common

Assoc injuries include popliteal artery injury, peroneal nerve injury, ligamentous and meniscal injuries

True Ortho Emergency!

Knee Dislocation

Early reduction using longitudinal traction is essential.

Neurovascular status is important to check pre&post-reduction

Ortho opinion and hospitalization required. If signs of popliteal artery injury: absent

pulses, bruits, distal ischemia, consult Vascular surgeon for possible arteriography.

Knee Dislocation:

Patella Dislocation

Mechanism is a twisting motion on an extended knee.– Patella is usually laterally displaced over lateral

condyle– May have tearing of medial joint capsule– Reduction involves conscious sedation, flexing

the hip, hyperextending the knee, and slide patella back into place

Patella Dislocation:

Patella Dislocation

Check X-ray to rule out fracture Tx: knee immobilizer, partial weight bearing,

NSAIDS, isometric quad. strengthening exercises and outpt. Follow Up to Ortho.

Quadriceps/Patellar Tendon Rupture

Mechanism is forceful contraction of quadriceps muscle or falling on a flexed knee.

Significant pain, swelling and inability to extend a fully flexed knee against minimal resistance.

May see a high riding patella on lateral x-ray view of knee

Tx: surgical repair

Patella Tendon Rupture:

Osteonecrosis

Bony infarction caused by disruption of blood flow

Can be primary or secondary– Primary: etiology unknown– Secondary: steroids, SLE

Osteonecrosis

Pts. Are typically elderly women who present w/acute knee pain

X-rays are usually normal early on, MRI is diagnostic

Tx: protective weight bearing, NSAIDS.– Advanced disease options include: arthroscopic

debridement, curretage,drilling of lesion, total knee arthroplasty

Patellar Tendonitis

AKA “Jumpers Knee” b/c seen in runners, basketball players, volleyball players and high jumpers

Pain is in patellar tendon, worse when going from sitting to standing position and running up hills

Tx: Heat, NSAIDS, quadriceps muscle strengthening

Fibula Fractures

Most fibula fractures are result of tibia fractures.

Treatment is determined by injury to tibia Fibula only bears 15% of body weight Isolated fibula fracture treated w/either knee

immobilization or elastic wrap.

Fibula Fracture:

Tibia Fractures

Mechanism usually involve torsional force, bending force or direct blow.

Closed, minimally displaced fractures can be treated w/reduction and immobilization

If fracture is displaced, ortho. C/S for further reduction

Watch for compartment syndrome Open fracture: immediate Ortho C/S, immobilize

fracture, sterile coverage of the wound, IV antibiotics, to OR for irrigation & debridement.

Tibia Fracture:

Achilles Tendon Rupture

Mechanism is forceful plantar flexion. Pt. may hear popping sound Risk factors: quinolone use, RA, SLE, steroid

use Dx: palpable gap in tendon, inability to walk

on toes Tx: splint in neutral position, refer to Ortho

and don’t forget the crutches.