Orthopaedic Knee Conditions Flashcards
Meniscal tear: prognosis
• UNLIKELY to HEAL = as GENERALLY OLDER PT. AFFECTED & they have POORER BLOOD SUPPLY
○ BLOOD SUPPLY to the MENISCUS RETREATS as WE AGE (> 19yrs = AVASCULAR) ○ IF IN RED ZONE = MAY HEAL
Meniscal tear: presentation
- PAIN = due to PULLING SENSATION - NOT CARTILAGE ITSELF
- CLICKING = NOT SPECIFIC
- LOCKING = CANNOT STRAIGHTEN by ITSELF, MORE SPECIFIC
- INTERMITTENT SWELLING = LOTS of FLUID to try & HEAL it, V. OBVIOUS as SO SUPERFICIAL - IF LOTS of FLUID, IT MAY NOT be a TEAR
Meniscal tear: aetiology
- ACUTE = TWISTING esp. in DEEP FLEXION
- DEGENERATIVE = OA
Meniscal tear: pathophysiology
- ACUTE = more a SINGLE TEAR
- DEGENERATIVE = as CARTILAGE starts to DEGENERATE = LESS SMOOTH SURFACE, FRONDS of CARTILAGE appear, WEAR & TEARS occurs, LITTLE FLAPS & PIECES COME OFF = BONE GRINDS ON BONE (ARTHRITIC CHANGES)
Meniscal tear: investigations/diagnosis
ON/E:
LOOK - effusion, patellar tap
FEEL - tender joint line at point of tear esp. in medial tear
MOVE - mechanical block to movement
○ OA = SLOW MOVEMENT + poss. LIMITED ROM ○ MENISCAL TEAR = NORMAL VELOCITY, CANNOT GO FURTHER BEYOND SPECIFIC POINT (JAMMING)
- MCMURRAY’S TEST +VE = DEEP FLEX KNEE, ROTATION, AXIAL PRESSURE, then EXTEND KNEE = will CLICK IF TEAR PRESENT
- FAIL DEEP SQUAT = TEAR if OFTEN in POSTERIOR MEDIAL THIRD - FLAP FLIPS INTO JOINT; DEEP FLEXION DIFFICULT so pt. UNABLE TO SQUAT ON AFFECTED SIDE
• THASSALY’S TEST +VE = HAND ON CHAIR, get pt. to BEND KNEE to 120°, TWIST - try to RECREATE MOVEMENTS that CAUSED TEAR
IMAGING:
* X-RAY = ARTHRITIS, # * MRI = MOST SENSITIVE TEXT, HIGH FALSE +VE RATE • USE TESTS in CONJUCTION w/ CLINICAL Hx to determine LVL of INTERVENTION
OA: pathophysiology
• DEGENERATIVE CHANGE of SYNOVIAL JOINTS
○ PROGRESSIVE LOSS of ARTICULAR CARTILAGE ○ 2ndary BONY CHANGES * PRIMARY = DEGENERATIVE CHANGES w/ NO PREDISPOSING FACTORS * SECONDARY = PREDISPOSING FACTORS e.g. POST-TRAUMATIC, POST-OPERATIVE, POST-INFECTIVE, MALPOSITION, MECHANICAL INSTABILITY, OSTEOCHONDRITIS DISSECANS ○ OA ASS. W/: INCREASED BMI, GENETIC FACTORS, AGE, OCCUPATION
OA: epidemiology
• WOMEN esp. if > 55yrs are at GREATER RISK
OA: presentation
• WORSENING PAIN + STIFFNESS of AFFECTED JOINT
○ PAIN = on INITIATING MOVEMENT ○ STIFFNESS = FOLLOWS INACTIVITY, OFTEN RESOLVES < 30mins ○ LIMITING EVERYDAY LIFE * SWELLING * VARUS DEFORMITY
OA: investigations/diagnosis
ON/E:
* REDUCED ROM w/ CREPITUS during both ACTIVE & PASSIVE MOVEMENTS * JOINT DEFORMITY & BONY OVERGROWTH from OSTEOPHYTES
IMAGING: X-RAY
OA: management
- NSAIDs
- PHYSIOTHERAPY = QUADRICEPS STRENGTHENING EXERCISES
- WGT. LOSS
- LOCAL STEROID INJECTIONS for SHORT-TERM USE
OSTEOTOMY esp. in YOUNG ACTIVE PT. as it can delay TOTAL KNEE REPLACEMENT for up to 10yrs
ACL injury: key anatomy
- COURSE = runs from BWTN TIBIAL EMINENCES to LATERAL WALL of INTERCONDYLAR NOTCH of FEMUR
- BLOOD SUPPLY = MIDDLE GENICULATE ARTERY
- INNERVATION = POSTERIOR ARTICULATE NN. (branch of TIBIAL NN.) for JOINT PROPRIOCEPTION - STABILITY
ACL injury: function
to = ANTERIOR TRANSLATION of TIBIA RELATIVE to FEMUR
• SECONDARY RESTRAINT to = TIBIAL ROTATION & VARUS/VALGUS STRESS
ACL injury: aetiology
• NON-CONTACT PIVOT INJURY = BAD LANDING MECHANICS
* ACUTE TEAR - VALGUS MOVEMENT causes ACL TEAR, LATERAL MENISCUS LIKELY to TEAR * May have MENISCAL TEAR - due to STRESSES PLACES on it due to INSTABILITY of KNEE & AMOUNT of SHEAR & MOVEMENT it has to DEAL w/
ACL injury: epidemiology
- F > M = 4.5 : 1
* LANDING MECHANICS causes NEUROMUSCULAR ACTIVATION PATTERNS
ACL injury: presentation
- Heard POP/CRACK = when landing badly + COLLAPSE
- IMMEDIATE SWELLING = 70%○ HAEMARTHROSIS = SNAPPED ACL BLOOD SUPPLY - ACL has a rlly good blood supply
○ CAN WALK in STRAIGHT LINE; KNEE TOO WOBBLY - as everything is in the wrong place, & so CANNOT TWIST & TURN
- DEEP PAIN
- FEELS ODD = KNEE in WRONG PLACE
ACL injury: investigations/diagnosis
ON/E:
LOOK - effusion if recent injury
MOVE - ANTERIOR DRAW, LACHMANN’S TEST, PIVOT SHIFT (not in clinic)
IMAGING:
* X-RAY = SEGOND # (AVULSION # of ANTEROLATERAL LIGAMENT), PATHOGNOMIC for ACL TEAR * MRI = ACL, MCL, MENISCII (LATERAL - SIMULTANEOUS w/ ACL TEAR in 48%; MEDIAL - 2ndary to SHEAR FORCE from CHRONIC INSTABILITY)
ACL injury: management
Non-operative - FOCUSED QUADRICEP PROGRAMME
OPERATIVE - ACL RECONSTRUCTION +/- partial menisectomy +/- ligament repair/augmentation, can use hamstring graft/quadriceps tendons/patellar tendons/donor tendons
MCL injury: management
Non-operative - majority
- REST
- NSAIDs
- PHYSIOTHERAPY e.g. QUADRICEPS STRENGTHENING
- BRACE for COMFORT
Operative
- For SEVERE TEARS, FAILED NON-OPERATIVE MANAGEMENT
- REPAIR/RECONSTRUCTION○ REPAIR = AVULSIONS - midsubstance tear w/ good tissue, an INTERNAL BRACE holds MCL TOGETHER○ RECONSTRUCTION = DAMAGED TISSUE, usually w/ semitendinosus
MCL injury: key anatomy
SUPERFICIAL - PRIMARY RESTRAINT to VALGUS STRESS
DEEP - contributes in FULL KNEE EXTENSION (attaches to medial meniscus + continuous w/ joint capsule)
MCL injury: aetiology + ass. injuries
• SEVERE VALGUS STRESS - usually CONTACT-RELATED (HIT at MEDIAL SIDE of KNEE)
ass. w/: ACL TEAR, MENISCAL TEAR
MCL injury: presentation
- Heard POP/CRACK
- PAIN ++ = MEDIAL SIDE
- UNABLE to CONTINUE PLAYING
- BRUISING = MEDIAL KNEE
- LOCALISED SWELLING
MCL injury: investigations/diagnosis
ON/E:
LOOK - medial swelling, bruising
FEEL - tender medial joint line, tender femoral insertion of MCL
MOVE - pain in full extension, opening on valgus stress
IMAGING:
* X-RAY = may be NORMAL, CALCIFICATION at FEMORAL INSERTION (PELLEGRINI-STIEDA) - CHRONIC INJURY * MRI = MODALITY of CHOICE, ASSESS LOCATION & SEVERITY of INJURY, IDENTIFY OTHER PATHOLOGIES e.g. CARTILAGE DAMAGE, CONDYLES, MENISCUS ○ MOST COMMON SITE = FEMORAL INSERTION
Osteochondritis dissecans: pathophysiology
- PATHOLOGICAL LESION affecting ARTICULAR CARTILAGE & SUBCHONDRAL BONE
- SIMILAR to AVN
Osteochondritis dissecans: aetiology
- HEREDITARY
- TRAUMATIC
- VASCULAR = ADULT FORM
Osteochondritis dissecans: location
• KNEE = MOST COMMON, POSTEROLATERAL ASPECT of MEDIAL FEMORAL CONDYLE (70%)
Osteochondritis dissecans: presentation
- ACTIVITY-RELATED PAIN (usually TEENAGERS) = POORLY LOCALISED
- RECURRENT EFFUSIONS = SWELLS UP ALL THE TIME (intermittent swelling is poss. meniscal tear)
- MECHANICAL SYMPTOMS = LOCKING, BLOCK to FULL MOVEMENT
Osteochondritis dissecans: investigations/diagnosis
ON/E:
LOOK - effusion
FEEL - localised tenderness
MOVE - stiffness, block to movement, Wilson’s test
IMAGING:
• X-RAY = ADD in TUNNEL VIEW (FLEXED 30 - 50°) - for POSTERIOR PART of CONDYLE
• MRI = LESION SIZE, STATUS of CARTILAGE & SUBCHONDRAL BONE, SIGNAL INTENSITY (OEDEMA suggests INSTABILITY of FRAGMENT)
Osteochondritis dissecans: management
Non-operative:
• RESTRICTED WGT.-BEARING = gives TIME FOR FAULT to HEAL by RESTRICTING DEEP FLEXION
• ROM BRACE
Operative:
• ARTHROSCOPY = SUBCHONDRAL DRILLING, FIXATION of LOOSE FRAGMENT
• OPEN FIXATION
