Knee Conditions

Question 1

Femoral shaft fractures causes

Answer 1

High- velocity trauma, child abuse. Elderly osteoporotic/ bone metastases/ bone lesions low-velocity injury.

Question 2

Femoral shaft fracture position of limb, complications and treatment

Answer 2

Muscles deforming force, proximal fragment abducted and flexed, distal segment adducted varus deformity and extended. Tense swollen thigh.

Closed (open worse) fractures -> blood loss -> hypovalaemic shock. May damage neurovascular structures RARE.

Surgical fixation ✅

Question 3

Distal femoral fractures causes and complications

Answer 3

Young High - energy sporting injury. Elderly- osteoporotic bone fall from standing.

Significant displacement -> popliteal artery damaged.

Question 4

Tibial plateau fractures cause, classification and complications

Answer 4

High-energy injuries, axial loading with varus or Vargas angulation.

Articulating surface of tibia affected. Unicondylar or bicondylar. Lateral is more common.

Articulate cartilage damaged-> post- traumatic osteoarthritis. Also can meniscal tears, anterior crucible ligament injuries.

Question 5

Patellar fractures, cause, 3 signs, 4 treatments

Answer 5

Direct impact injury/ eccentric contraction quadriceps. 20-50yrs.

Palpable defect patella, haemarthrosis. If extensor muscle disrupted -> unable straight leg raise. 8% bipartite patellar naturally.

Displaced: reduction, surgical fixation.
Undisplaced: splinting, crutches.

Question 6

Patella dislocation cause and treatment

Answer 6

Subluxation = partial displacement.

Q-angle most common laterally.

Trauma, twisting injury slight flexion/ direct blow. Athletic teens, internal rotation of femur planted foot.

✅ extending knee, manually reducing patella. Then immobilise, physiotherapist strengthen VMO (vastest medialis obliquus)

Question 7

Patella dislocation 5 predisposing factors

Answer 7

Generalised ligamentous laxity, weakness quadriceps, shallow trochlear groove with flat lateral lip, long patellar ligament, previous dislocations

Question 8

Meniscal injuries (tear) cause, 7 symptoms, 2 complications

Answer 8

Meniscal tears most common, sudden twisting motion weight-bearing flexion.

Intermittent pain, knee clicking, catching, locking, giving way, swelling. Joint line tenderness.

Haemarthrosis (indicates tear peripheral vascular aspect OR associated injury anterior crucible ligament), chronic effusion can occur synovitis

Question 9

Meniscal tear treatment

Answer 9

Acute traumatic- surgically (meniscetomy or meniscal repair)

Chronic- normally conservative management

Question 10

Collateral ligament injury, 2 classifications and 3 symptoms

Answer 10

Acute valgus strain (lateral angulation of distal segment) - medical CL . More common.

Varus strain (medial angulation distal segment) - lateral CL. Higher chance -> knee instability - lateral tibial plateau shallower and less stable socket for femoral condyle.

Pain and swelling, knee unstable give way

Question 11

Unhappy triad

Answer 11

‘Blown knee’ injury to anterior cruciate ligament, medial meniscus and medial collateral ligament.

Strong force lateral knee.

Question 12

Anterior cruciate ligament tear cause, symptoms, treatment, tests

Answer 12

Quick deceleration/ hyper extension OR rotational injury, large force back knee partly flexed.

Popping sensation -> swelling, instability tibia slides anterior under femur ‘giving way’. Anterolateral rotatory instability tibia MR during flexion knee & opens up laterally.

Low demand function well, sportsmen need surgical reconstruction.

Tests: anterior drawer test, Lachman’s test

Question 13

Posterior cruciate ligament injury cause, treatment, test

Answer 13

Dashboard injury- knee flexed large force upper tibia displacing it posteriorly. Fall on flexed knee with ankle plantatflexed. Severe hyperextension.

Tibia displaced posteriorly on femur

Conservative management- bracing and rehabilitation

Tests: posterior drawer test

Question 14

Dislocation knee joint, definition, cause, complications, treatment

Answer 14

Uncommon, high energy trauma, 3/4 ligaments must rupture (MCL, LCL, ACL, PCL)

Associated arterial injury common, popliteal artery immobile -> tear = haematology OR -> crushed or -> traction injury (endothelial damage thrombotic occlusion)

Reduction of joint, assess vascularity e.g. MRA (magnetic resonance angiography)

Question 15

Swellings around knee 3 types

Answer 15

Bony e.g. Osgood- Schlatter’s disease

Soft tissue - localised e.g. enlarged popliteal lymph node/ popliteal artery aneurysm
- generalised e.g. lymphoedema of lower limb

Fluid -inside joint = effusion
- outside joint = soft tissue haematology

Question 16

Knee effusions acute and delayed classifications

Answer 16

Accumulation of fluid inside joint, never normal.

Acute <6hrs after injury

• haemarthrosis (ACL rupture)
• Lipo-haemarthrosis (blood and fat) fracture. Fat (darker)-fluid interface on X-Ray

or delayed (usually reactive synovitis)

Question 17

Pre-patellar bursitis 5 symptoms and 3 causes

Answer 17

Superficial bursa, synovial lining.

Knee pain and swelling, erythema, difficult to walk, not able to kneel.

Repetitive trauma ‘Housemaid’s knee’ OR history of fall on knee Or blunt trauma to knee

Question 18

Infrapatellar bursitis cause

Answer 18

Two bursae, one superficial between patellar tendon and skin. Most common.One deep between patellar tendon and tibia bone.

Repetitive microtrauma kneeling ‘clergyman’s knee’

Question 19

Suprapateller bursitis and knee effusion cause

Answer 19

Extension of synovial cavity of knee, knee effusion swelling pouch (superior beneath patellar under quadriceps), sign of pathology to knee I.e.: osteoarthritis, rheumatoid arthritis, infection (septic A), gout and pseudogout, repetitive microtrauma (running soft/uneven surfaces)

Question 20

Semi membranous bursitis position and cause

Answer 20

’popliteal cyst’/ ‘Baker’s cyst’Indirect consequence of swelling within knee. Beneath Deep fascia of popliteal fossa between semi membranous muscle and media, head gastrocnemius. Attached posterior capsule of knee. Fluid from knee get into semimebrnaous bursa.

Question 21

Osgood-Schlatter’s disease definition, who, symptoms, treatment

Answer 21

Inflammation of apophysis of patellar ligament into tibial tuberosity.

Teens sport

Localised pain (running, jumping, squatting, ascending, descending, kneeling) and swelling.

Rest and ice, resolve when apophysis fuses, bony prominence usually remains.

Question 22

Knee osteoarthritis 6 symptoms

Answer 22

Stiffness, swelling, 
knee pain (chronic Low level with severe flare ups, precipitated by activities a.k.a bending/ kneeling/ squatting/climbing), or pain and stiffness worse after prolonged activity or rest),
varus deformity (deviation distal component toward midline) or fixed flexion deformity (knee can’t be fully extended),
Loss articulate cartilage-> friction bone rubs on bone (crepitus), May get effusion, knee give way (down stairs)

Question 23

Risks and types of Osteoarthritis of knee

Answer 23

Risks: older, female, previous trauma! Obesity, family history OA, another condition affects joint

Uni/bi/tri compartmental (affecting one/2/3 medial femorotibial, lateral femorotibial and patellofemoral compartments.

Question 24

Treatment OA knee 5

Answer 24

Strengthening exercises -> analgesia-> weight loss-> activity modification-> surgery (TKR)

Question 25

Septic arthritis of knee definition

Answer 25

Invasion of joint space by micro-organisms, usually bacteria/ viruses/ mycobacterium/ fungi. Different to reactive = sterile inflammatory from extra-articulate infection e.g. gastroenteritis

Usually staphylococcus aureus or staph. Epidermidis, neisseria gonorrhoeae, group B streptococci

Question 26

Risks septic arthritis of knee

Answer 26

Older, diabetes mellitus, rheumatoid arthritis, immunosuppressive, IV drugs abuse, prosthetic joints (intra-operative contamination or haematogenous spread from distant infective focus) months or years after initial operation.

Question 27

Septic arthritis cause and treatment

Answer 27

Damage articulate cartilage from organisms’s pathologic response OR hosts’s immune response (neutrophils-> cytokines-> hydrolysis collagen and proteoglycan.

Aspiration of joint sent for urgent microscopy, culture and sensitivities. High morbidity.

Question 28

Septic arthritis symptoms

Answer 28

Fever, pain, reduced range of motion, erythema, swelling, warmth, tenderness, draining sinus (tract between site of infection and surface overlying skin)