6002 Knee & Lower Leg Cheat Sheet by bee.f

• YELLOW

• Aetiology (risk factors):

- Most commonly injured ligament in the knee (almost ½ of all knee injuries)
- F>M (esp. F athletes 4.5:1)
- Possible factors contri­buting to increased F risk include: weaker hamstr­ings, prefer­ential recrui­tment of quads during decele­ration, & weaker core stability
Biomec­hanics & landing factors:
- F landing mechanics mat ↑ injury risk, w/ ↑ valgus angulation & knee EXT
- ↓ hip & knee FX & ↓ fatigue resistance also contribute to ↑ stress on the ACL
Other risk factors:
- Anatom­ical: high BMI, smaller femoral notch, imping­ement on the notch, smaller ACL, hyperm­obi­lity, joint laxity, & previous ACL injury
Hormonal & genetic factors:
- Preovu­latory phase, may affect coordi­nation & predispose females to ACL injury
- Females on OCP were noted less affected
Associated injuries w/ ACL ruptures:
- Both intra & extra-­art­icular injuries can accompany acute ACL ruptures
- Meniscal tears are common, w/ lateral meniscus injury more prevalent in acute cases, & medial meniscus more involved in chronic cases
- Other ligaments (PCL, LCL, & PLC) could also be injured in conjun­ction w/ ACL
Chronic ACL deficiency effects:
- Detrim­ental effects on the knee
- Develo­pment of chondral injuries & complex, unrepa­irable meniscal tears is observed (e.g bucket handle medial meniscus tears)

• Clinical presen­tation:

- Hx of injury mechanisms
- Pt would complain of hearin­g/f­eeling a sudden "­pop­" w/ associated deep knee px
- About 70% would experience immediate swelling due to haemarthrosis
- Other Ssx: knee "­giving way", difficulty ambula­ting, reduced knee ROM

• Diagnosis:

- MRI is the 1° modality to diagnose ACL pathology
- Knee arthro­scopy to differ­entiate complete from partial tears & chronic tears (gold standard test)
- Radiog­raphy to rule out fractures & other osseous injuries

• Manage­ment:

Non-op­erative manage­ment:
- Indica­tion: when there's reduced ACL laxity on low-demand pts or athletes involved in no cutting or pivoting activities or partial ACL tears
- RICE
- Non-WB (crutches or wheelchair)
- NSAIDs
- Phase 1: acute sympto­matic treatment
- Phase 2: 12 weeks of supervised physio­therapy starting w/ regaining full ROM & progre­ssion to quad, hamstring, hip ABD & core strengthening
Operative manage­ment:
- Indica­tion: complete ACL rupture in younger or older active, high-d­emand pts, & partial ACL rupture w. functional instability
- Two options: ACL recons­tru­ction or repair

• YELLOW

• Aetiology (risk factors):

- 40% of PLC (poste­rol­ateral corner) & LCL injuries result from contact sports
- Other causes include trauma, motor vehicle accidents, & falls
- F>M
- High-c­ontact sports
- Sports involving high-v­elocity pivoting & jumping
- Tennis & gymnastics are most specific fro isolated LCL injuries
- Prior knee, ankle, or hip injury increases the risk

• Clinical presen­tation:

- Acute event consistent w/ a medial blow to the knee while fully EXT, or extreme non-co­ntact varus bending
- Complain of sudden onset lateral knee px, swelling, & ecchymosis after the injury
- May report thrust gait, inc. foot kicking in mid-stance
- May complain of parest­hesias over the lateral lower extremity, & weakness &/or a foot drop
- Gain complete Hx inc. bleedi­ng/clot disorders, previous surgeries, occupa­tion, gait, ambula­tio­n-a­ssisted devices, living situation (stairs at home)

• Diagnosis:

- MRI is the gold standard
- US useful for rapid diagnosis
Classi­fic­ation of injury:
- Grade 1: Mild sprain - diagnosed w/ lateral knee tender­ness, no instab­ility mechanical Ssx
- Grade 2: Partial tear - diagnosed w/ more severe localised lateral & poster­ola­teral knee px, as well as swelling
- Grade 3: Complete tear - px & swelling vary in pts, usually associated w/ PLC & other related injuries, & mechanical Ssx

• Manage­ment:

- Acutely, all grades treated w/ RICE & NSAIDs
- Grade 1 & 2: non-op­era­tive, non-WB for 1 week for better px control; next 3-6 weeks, the pt should be in a hinged­-knee brace while performing functional rehab
- Grade 3: surgical recons­tru­ction (best results), post op rehab and functional exercises

• YELLOW

• Aetiology (risk factors):

- Caused by extreme anterior force applied to the proximal tibia of the FX knee
- Dashboard injuries during car accident or falling forward onto a FX knee
- M>F (2:1)
- Motorcycle accidents (28%) & soccer­-re­lated injuries (25%) are the leading causes

• Clinical presen­tation:

- Pts often present w/ acute onset of posterior knee px, swelling, & instability
- Hx includes mechanism of injury, ic. falling onto FX knee or recent vehicle accident

• Diagnosis:

- MRI is the gold standard
- Initial imaging w/ plain X-rays
Classi­fic­ation of injury:
- Grade 1 (partial tear) - 1-5mm posterior transl­ation, tibia remains anterior to femoral condyles
- Grade 2 (complete isolated) - 6-10mm posterior tibial transl­ation, complete tear of PCL w/o another injury, anterior tibia flush w/ femoral condyles
- Grade 3 (complete PCL w/ combined capsular &/or ligame­ntous injury) - >10mm posterior tibial transl­ation, tibia posterior to femoral condyles which may indicate a concom­itant capsul­oli­gam­entous injury

• Manage­ment:

- Variables to consider: Acute or chronic; isolated or combined
Non-op­era­tive:
- Acute grade 1 & 2 injuries w/ posterior tibial transl­ation (8-12mm)
- Grade 3 injuries w/ mild Ssx or low-demand activities
- Acute treatment inv. RICE, initial knee bracing, & crutches
- Rehab focuses on knee EXT strengthening
- Est. return­-to­-play in 2-4 weeks for Grade 1 & 2 injuries
- Grade 3 may inv. knee immobi­lis­ation followed by rehab
Operative:
- Acute injuries w/ tibial transl­ation >12mm, associated meniscal tears, disloc­ation, bony avulsions, & combined injuries
- Chronic injuries w/ posterior tibial transl­ation >8mm, sympto­matic cases, instab­ility, & combined injuries
- Arthro­scopic procedures
- Reconstruction
- Graft fixations
- High tibial osteotomy

• GREEN

• Aetiology (risk factors):

- Children aged 4-7 yo
- Adults aged 35-70
- Most commonly found in adults w/ Hx of trauma, knee joint diseases (OA, RA, etc), or as incidental findings
- They form due to accumu­lation & extrusion of synovial fluid between the semime­bra­nosus & medial head of the gastroc
- Popliteal cysts are located on the medial side of the popliteal fossa just below the crease at the posterior knee
- Prevalence increases w/ age, likely due to an increase in knee-b­urial commun­ication

• Clinical presen­tation:

- Sensation of tightness, discom­fort, or px behind the knee
- Swelling Moree noticeable when standing w/ full knee EXT
- Swelling reduces or disappears when the knee is flexed to 45° (Foucher's sign)
- Px worsens w/ increased activity & may limit full knee FX & EXT

• Diagnosis:

Diagnosis methods:
- Pt stand & full knee EXT
- Mass is most prominent in this position
- Mass often softens or disappears when the knee is FX to 45° (Foucher's sign)
- Supine exam: knee passively moved from full EXT to at least 90° FX
Imaging:
- Plain radiograph & US
- MRI is recomm­ended, esp. if consid­ering surgery

• Manage­ment:

- Asympt­omatic cases are managed through observ­ation & reassu­rance alone
- Essential to treat any underlying joint disorder in pts w/ sympto­matic Baker's cysts
- Helps reduce synovial fluid accumu­lation & cyst enlargement
Non-op­era­tive:
- Rest/a­ctivity modification
- NSAIDs
- Physical therapy & rehab regimes are effective for minimal Ssx & smaller degene­rative meniscal tears
- Aspiration & steroid injection
- Lower recurrence in younger pts
- Higher recurrence rates in older pts & those w/ degene­rative meniscal tears
Operative:
- Arthroscopy
- Open cyst excision (not recomm­ended in case of underlying degene­ration due to recurrence risk)

• YELLOW

• Aetiology (risk factors):

- Often pts >65 yo, w/ 30-50% >85 yo
- M>F
- Rare <60 yo
- High prevalence of radiog­raphic chondr­oca­lci­nosis in the general population
Comorb­idities associated w/ CPPD:
- Hyperparathyroidism
- Gout
- OA
- RA
- Hemochromatosis
Other related comorb­idi­ties:
- Osteoporosis
- Hypomagnesium
- Chronic kidney disease
- Calcium supple­men­tation

• Clinical & physical presen­tation:

Acute cases:
- Typically, self-l­imi­ting, & inflam­mation resolves within days - weeks w/ treatment
- Similar to acute rate arthropathy
- Joint oedema, erythema, & tenderness
- Up to 50% may have a low-grade fever
- Most commonly affected joint: knee
- Other affected joints: hip, shoulders
Chronic cases:
- May show Ssx of RA inc. morning stiffness, localised oedema, & ↓ ROM
- Waxing & waning episodes of non-sy­nch­ronous, inflam­matory arthritis
- Affeects multiple non-WB joint: wrist & MCP joint
- Causes "­crowned dens syndro­me" (depos­ition of CPP around C2)
- Mostly asympt­omatic

• Compli­cat­ions:

- Potential of triggering inflam­matory responses
- Presence of chondr­oca­lci­nosis has associ­ations w/ degrad­ation of menisci & synovial tissue
- Pts rarely present w/ palpable nodules (resem­bling gout) that may lead to further joint degradation
- Rare spinal involv­emen, causing clinical manife­sta­tions like spine stiffness & bony ankylosis (resem­bling AS)
- Some pts present w/ manife­sta­tions similar to DISH w/ PLL calcif­ication leading to spinal cord compre­ssion Ssx

• Ddx:

- Tenosy­novitis w/ carpal or cubital tunnel s. can occur (multiple joints affected)
- RA
- AS
- Erosive OA
- Gout

• RED

• Aetiology (risk factors):

- M>F (7.3:0.7)
- Majority of cases result from trauma, w/ tibial shaft fracture being the most common
- More common in males <35 yo, possibly due to larger muscle mass & high-e­nergy trauma involvement
- Pts w/ bleeding diathesis (e.g. hemoph­ilia) are at high risk
- ACS reported w/o trauma in paediatric leukaemia cases
- Pts w/o fractures at high risk of compli­cations & delayed treatment
- Other causes:** soft tissue injuries, burns, vascular injuries, crush injuries, drug overdoses, reperc­ussion injuries, thromb­osis, bleeding disorders, infect­ions, improperly placed casts or splints, tight circum­fer­ential bandages, penetr­ating trauma, intense athletic activity, & poor positi­oning during surgery
- In children, suprac­ondylar # of the humerus & ulnar/­radial # are associated w/ compar­tment syndrome

• Clinical presen­tation:

- Can occur within few hours to up to 48h after trauma
- Px is severe & dispro­por­tionate to the injury; may be felt as a burning sensation or deep ache
- Initially, px may only occur w/ passive stretching but can be absent in advanced cases
- Parest­hesia, hypoes­thesia, or poorly localised deep muscular px may be present
- The "5 P's" (px, pulsel­ess­ness, parest­hesia, paralysis, & pallor) are classic signs, but they're typically late findings
- Parest­hesia may occur earlier
- In some cases, a pulse may still be present, even in a severely compro­mised extremity

• Diagnosis:

- Radiog­raphs are recomm­ended if # suspected
- Measur­ement of intrac­omp­art­mental pressure (not required), can aid in Dx
- Normal pressure: 0-8mmHg
- Abnormal: exceeding 30mmHg indicates compar­tment s. & necess­itates intervention
- Pressure within 10-30mmHg of diastolic blood pressure suggests inadequate perfusion & relative ischemia, prompting clinical attention
- DUS can be used to detect occlusion or thrombus
- Elevated CPK levels may suggest muscle breakdown from ischemia, damage, or rhabdomyolysis
- Pre-op­erative studies: CBC & coagul­ation studies

• Manage­ment:

- Immediate surgical consult
- Keeping extremity at heart level

• RED

• Aetiology (risk factors):

- Relatively common among young adult athletes (running, endurance training, soccer, field hockey, & lacrosse)
- Anterior compar­tment most commonly affected (70% of cases), then deep posterior
- B limb in 37-82% of sympto­matic cases
- 20-25 yo, M>F, & often B
- Associated w/ sports like running or skating, & higher activity intensities
- Can result from overuse injuries, repetitive mechanisms causing tissue degene­ration, scar formation, & military training
- Pts w/ decreased fascial elasticity may be at risk for nerve entrapment & quicker rises in pathol­ogical pressures

• Clinical presen­tation:

- Pts often present following sport-­related activity ro exertion w/ non-sp­ecific leg px & persist after strenuous or repetitive activity
- Ssx will predic­tably abate following activity cessation
- Particular attention to pts charac­ter­isation of px during strenuous activity, well-l­oca­lised to a specific compar­tment, & the px/Ssx disappear quickly after the cessation of activity
- Pts will generally complain of discomfort described as squeezing, cramping, aching, or burning that typically begins within 15-20 minutes of activity
- Discomfort resolves completely w/ rest, although the duration may vary

• Diagnosis:

Pedowitz criteria:
-Rule out a Dx of CECS
- Resting pressure ≧ 15mmHg &/or a pressure of ≧ 30mmHg at 1 min post-e­xercise in any compar­tment, &/or;
- Post-e­xercise pressure greater than 20mmHg at 5 min post-e­xercise

• Manage­ment:

- Conser­vative treatment generally ineffe­ctive, inc. rest, activity modifi­cation, stretc­hing, orthotics, & physical therapy
- Non-op­erative modalities inc. NSAIDs, inject­ions, gait training (forefoot strike patterns)
- Open fasciotomy is the predom­inant surgical technique

• GREEN

• Aetiology (risk factors):

- Most common monone­uro­pathy in the LL & 3rd most common focal neuropathy overall (after carpal tunnel s. & ulnar neuropathies)
- Common in traumatic injuries in young athletes (e.g. football, soccer) & following high energy trauma (car accidents) in adults
- Occurs in about 16-40% of knee dislocations
Trauma or injury to the knee:
- Knee dislocation
- Direct impact, penetr­ating trauma, or lacerations
- Fibula #, esp. proximal fibula
External compre­ssion sources:
- Tight splint/cast
- Compre­ssion wrapping/bandage
- Habitual leg crossing
- Prolonged bed rest
- Positi­oning during anaest­hesia & surgery (important to pad bony prominences)
Systemic causes:
- Diabetes mellitus
- Inflam­matory conditions
- Anorexia nervosa
Others:
- Intramural ganglion
- Peripheral nerve tumour
- Iatrogenic injury following surgery to the hip, knee, & ankle

• Physical examin­ation:

- Gait: signif­icant for chronic peroneal nerve palsy w/ foot drop, high stoppage gait weakened dorsif­lexors to prevent toe dragging
Locali­sation of lesions:
- Proximal lesions (e.g. knee disloc­ations) may present w/ numbness in both superf­icial & deep n. distributions
- Upper lateral leg numbness indicates a lesion proximal to fibular head (possibly inv. sciatic n. or lumbos­acral n. roots)
- Lower lateral leg & dorms of the foot involv­ement suggests superf­icial peroneal n.
- Altered sensation in the dorsal aspect of the first web space implicates the deep peroneal n.
Motor involv­ement testing:
- Assess foot eversion (super­ficial n.) & foot/toe dorsif­lexion (deep n.)
- Weakness in both suggests common Peroneal n. involvement
- Proximal lesion may result in both distributions
- Detailed examin­ation of dorsif­lexion ability is crucial
Tinel sign:
- Tapping along the nerve course, esp. around the fibular neck
- +ve test = tingling or parest­hesia distally

• Manage­ment:

- Full physical therapy
- Ankle-foot orthoses, even for foot-drop when surgery isn't warranted
- Surgical indica­tors: rapid deteri­oration & no signs of improv­ement within 3 months & open injuries w. suspected nerve laceration
-Open lacera­tions should undergo explor­ation & surgical repair within 72h

• YELLOW

• Aetiology (risk factors):

- 61/100,000 in general population (USA), 9/1000 in military population
- 15% of sports injuries
- M>F
- Age >40 yo
- ACL deficient knees, esp. if ACL recons­tru­ction is delayed beyond 1 year from initial injury
- Medial­>la­teral meniscal tears
- Increased risk factors: infant­ry-­related duties, frequent squatt­ing­/kn­eeling, & partic­ipation in sports like soccer, rugby, football, basket­ball, baseball, skiing, & wrestling
- Traumatic impacts to the knee can lead to isolated meniscal tears or tears concom­itant w/ bony lesions or damage to primary stabil­ising ligaments (ACL & MCL)
- Less force is required for tears in indivi­duals w/ degene­rative changes of the menisci, typically seen in adults >40 w. concom­itant OA
- Isolated meniscal tears result from rotational or shearing forces across the tibiof­emoral joint, esp. during activities w/ increased closed kinematic chain FX, heavy lifting, rapid accele­rat­ion­/de­cel­era­tion, change of direction, & jumping

• Clinical presen­tation:

- "­POP­" sensation w/ immediate knee effusion suggests ACL tear w/ possible medial meniscal involvement
- Gradual effusion over 24h indicates an isolated meniscal tear
- Ssx can be insidious, featuring low-grade effusi­on& stiffness w/o a specific triggering event
- Px commonly reported along the antero­medial or antero­lateral joint line
- Additional Ssx: locking, clicking, catching, interm­ittent inability to fully EXT the knee, & a sense of the knee giving way

• Diagnosis:

- Begin w/ radiog­raphs - AP, lateral, oblique, sunrise, & WB views to assess concom­itant bony pathol­ogies, loose bodies, & OA
- Arthro­scopy is the gold standard
- MRI is the best mode of imaging to Dx & charac­terise tears

• Ddx:

- ACL injury
- Contusions
- ITB syndrome
- Knee osteochondritis
- LCL injury
- Lumbos­acral radiculopathy
- MCL injuy
- Medial synovial plica irritation
- Patell­ofe­moral joint syndrome
- PCL injury

• GREEN

• Aetiology (risk factors):

- Leading cause of knee px in adolescent athletes
- Onset typically aligns w/ growth spurts: 10-15 M & 8-13 F
- M>F
- 9.8% of adoles­cents 12-15 yo (11.4% M; 8.3% F)
- B Ssx observed in 20-30% of pts
- Overuse injury due to repetitive strain from patellar tendon
- Force increases w/ higher activity levels, after rapid growth
- Predis­posing factors: poor flexib­ility of quadriceps & hamstr­ings, extensor mechanism misali­gnment

• Clinical presen­tation:

- Common Ssx: anterior knee px
- Presen­tation: w/ or w/o swelling, unilateral or bilateral
- Onset: typically insidious, w/o preceding trauma
- Nature of px: dull ache localised over tibial tubercle
- Px progre­ssion: gradually increases w/ activity
- Px relief: typically improves w/ rest
- Duration of relief: subsides minutes to hours after stopping activity or sport
- Exacer­bating factors: running, jumping, direct knee trauma, kneeling, & squatting

• Diagnosis:

- 1° Dx clinic­ally, radiog­raphic evaluation typically not necessary
- Consider comparing B images to help delineate normal vs abnormal in the pt
Radiog­raphic use:
- Plain radiog­raphs may be employed in severe or atypical presentations
- Used to rule out additional conditions like fractures, infect­ions, or bone tumours
- Assessment fro avulsion injury or other traumas may necess­itate radiog­raphic evaluation
Classic findings:
- Elevated tibial tubercle w/ soft tissue swelling
- Fragme­ntation of the apophysis
- Calcif­ication in the distal patellar tendon

• Manage­ment:

- Excellent prognosis
- Self-l­imiting but time to resolution can take up to 2 yrs until apophysis fuses
- Surgery rarely indicated, low benefit & high compli­cation risk
- Relative rest & activity modifi­cation based on px levels
- Partic­ipation in sports allowed if px resolves w/ rest & doesn't limit activities
Px manage­ment:
- Ice & NSAIDs
- Protective knee pad recomm­ended over tibial tubercle to prevent direct trauma
- Hamstring & quadriceps stretc­hing, & strengthening
- In severe cases, short knee immobi­lis­ation might be considered
Refractory cases:
- In up to 10%, Ssx may persist >1-2 yrs beyond skeletal maturity
- Ossicle excision may be performed in skeletally mature pts w/ persistent Ssx

• YELLOW

• Aetiology (risk factors):

- Highest incidence 12-19 yo
- 9.5-29 / 100,00
- M>F
- 75% of affected pts have knee lesion, w/ 64% localised in the medial femoral condyle
- 32% of knee lesions are found in the lateral condyle, while other cases localise to the trochlea, patella, & tibial plateau
- Usually unilat­eral, but 7-25% of pts have B disease
- Theories inc. micro-­trauma, ischemia, & genetic predisposition
- Pts w. extreme obesity & elevated BMI face an increased risk of developing OCD
- Repetitive trauma is widely considered the 1° cause of OCD of the knee
- Adult form of OCD is believed to result from vascular insult

• Clinical presen­tation:

- Vague, poorly localised knee px that worsens w/ activity
- Stiffness & occasional swelling may occur during or after activity as the disease progresses
- Advanced stages may be indicated by locking or catching, suggesting the presence of a sizeable loose body in the knee
- Hx of trauma, recent increase in activity level, previous knee injuries, & the presence of mechanical Ssx
- Approx. 80% of pts report px when WB
- Juvenile: interm­ittent, activi­ty-­ass­ociated px poorly localised around the anterior aspect of the joint
- Adult: more likely effusion, limited ROM, or mechanical Ssx such as 'catching or locking'
- Depending on chronicity of the lesion, pts may report quadriceps dysfun­ction & interm­ittent knee instab­ility

• Diagnosis:

- Arthro­scopy is the gold standard for assessing lesion stability
- Plain radiog­raphs used to locate the lesion, assess growth plates, & rule out other conditions
- Initial radiog­raphs may appear normal in OCD
Lesion charac­ter­istics:
- Distinct Lucent areas w/ varying density levels
- Calcif­ica­tions & Lucent lines may or may not be present, depending on lesion severity
- B comparison
Classi­fic­ation:
- Lesion location can provide important prognostic info
- Atypical locations like trochlea or patella may not respond effect­ively to conser­vative management
MRI evalua­tion:
- Useful for assessing unstable lesions presenting w/ mechanical Ssx or knee effusion
- Unstable lesions on mRI may exhibit increased T2 signal, destru­ction of overlying articular cartilage, or multiple cyst-like foci
- Gadolinium contrast may be necessary for assessing blood supply & stability uncertainties
- Line of high signal intensity between fragment & underlying bone is a sensitive progno­sti­cator

• Manage­ment:

- Prognosis influenced by age, location & appearance of lesion
Non-op­era­tive:
- Recomm­ended for juvenile pts w/o a displaced fragment OR stage 1-3 disease
- Immobi­lis­ation & protected WB for 4-6 weeks
- Physical therapy initiated after immobi­lis­ation & continued until pain-free, achieving full ROM, strength, power, & mobility
- NSAIDs for px & edema
Operative:
- Surgery recomm­ended if conser­vative treatment ineffe­ctive after 3-6 months or if not suitable
- 1° tre­atment for Ssx related to OCD in adults, stage 2 disease, or expanding lesions on radiographs
- Surgical interv­ention warranted in juveniles w/ stage 4 disease, loose bodies, unstable lesions, or impending physeal closure

• GREEN

• Aetiology (risk factors):

- F>M
- Increased Q angles in F (lateral positi­oning of the patella)
- No hormonal cause has been identified
- Active young adults (esp. running sports), & workers who stress their patell­ofe­moral joint (stairs, kneeling)
- Often multifactorial
- LL malali­gnment & patellar maltra­cking play a signif­icant role
- Foot & ankle variances: pes planus can lead to increased lateral wear of the patell­ofe­moral joint
- Miserable malali­gnment syndrome, w/ femoral ante version, gene valium, & pronated feet
- Muscular weakness: vests medals & core m.
- Patellar lesions from injuries, immobi­lis­ation, or surgical procedures causing quadriceps atrophy
- Abnormal wear & tear of the patell­ofe­moral joint's hyaline cartilage
- Iatrogenic factors: injecting chondr­otoxic medica­tions into joints

• Clinical presen­tation:

- CC: anterior knee px
- Pts may report insidious onset of diffuse retrop­atellar or pre patellar px, exacer­bated by activities stressing the patell­ofe­moral joint
- Aggrav­ating factors: stair ascending or descen­ding, squatting, kneeling, running, & prolonged sitting (theatre px)
- Additional Ssx: effusion, quadriceps wasting, & retrop­atellar crepitus (not specific to CMP)
- Hx evalua­tion: previous trauma, comorbid condit­ions, joint stability, foot & ankle issues, & activity levels

• Diagnosis:

- Reliable Dx requires excluding other conditions causing anterior knee px
- Arthro­scopy is the most efficient (invasive, so non-in­vasive methods essential for initial Dx)
- Plain radiog­raphs: lower sensit­ivity in earlier stages
- CT: measures TT-TG distance & detects torsional deform­ities of the LL
- MRI: modality of choice fro articular cartilage, esp. T2 sequence

• Manage­ment:

- Min. 12 months of conser­vative management before consid­ering surgery
- May be reversible
- Could progress to patell­ofe­moral OA
- Pts often fully recover (can take months to yrs)
Conser­vative 1st phase:
- Activity modification
- RICE
- NSAIDs
Conser­vative 2nd phase:
- Knee + hip exercise to increase strength, mobility & function
- Patella taping

• GREEN

• Aetiology (risk factors):

- 13-20% incidence in runners
- Up to 35% in military
- Factors contri­buting: signif­icant increasing loads, volume, & high-i­mpact exercises
- Intrinsic risk factors: F gender, previous MTSS Hx, high BMI, navicular drop, ankle plantar FX range, hip EXT ROT range
- Overuse condition, specif­ically a tibial bony overload injury w/ associated periostitis
- Common for: recurrent impact exercise, such as running, jumping, & military personnel
- Suggested link between vitamin D & increased risk of stress injury

• Clinical presen­tation:

- Presence of exerci­se-­induced px along the distal 2/3 of the medial tibial border
- Presence of px provoked during or after physical activity, which reduces w/ relative rest
- The absence of cramping, burning px over the posterior compar­tment &/or numbne­ss/­tin­gling in the foot

• Diagnosis:

- Dx through clinical & physical findings
- Imaging done when uncertain about cause or to rule out other exerci­se-­induced LL injuries
- Plain radiog­raphs are normal in MTSS & early stress fractures
- "­dreaded black line" indicates a stress fracture
- MRI is preferred for identi­fying MTSS & higher­-grade bone stress injuries like tibial stress fractures

• Manage­ment:

- Full recovery is expected
- Rest & activity modifi­cation w/ less repeti­tive, load-b­earing exercise
- Additional therapies: iontop­hor­esis, phonop­hor­esis, ice massage, US therapy, periosteal pecking, & extrac­orp­oreal shockwave therapy
- No benefit: low-energy laser therapy, stretc­hing, streng­the­ning, LL braces, & compre­ssion stockings
- Slow response cases: optimising calcium & vitamin D status & gait retraining may improve recovery & prevent further progre­ssion

• YELLOW

• Aetiology (risk factors):

- Up to 30% of general population
- F>M
- Risk factors: F gender, multip­arty, high BMI, consti­pation, Hx of venous thromb­osis, smoking, & circul­ating iron levels
- Both genetic & enviro­nmental factors

• Clinical presen­tation:

- Leg heaviness
- Itching
- Cramps
- Mild tenderness
- Skin discoloration
- Exercise intolerance
- Leg fatigue

• Diagnosis:

CEAP classi­fic­ation:
- C0: no visible, palpable signs
- C1: spider veins
- C2: varicose veins
- C3: edema
- C4a: pigmen­tation, eczema
- C4b: lipodermatoslerosis
- C5: healed ulcer
- C6: active ulcer
- Colour duplex venous US exam is recomm­ended for suspected venous reflux

• Manage­ment:

- No cure
- Long-term graduated compre­ssion stockings, leg elevation, & oral px medication
- Surgery (recur­rence is likely )

• RED

• Aetiology (risk factors):

- Incidence of 20-40 million / year
- Gender dominance depending on type of vasculitis
- Giant cell arteritis is the most common form
- Risk factors: Behcet disease (ancient Silk route), Takayasu disease (South Asian), Kawasaki disease (children <5), hepatitis B/C

• Clinical presen­tation:

- Ssx dependent on location of vasculitis
- Potential organ damage from vasculitis
- Fevers, unexpl­ained weight loss
- Nose bleeding, hemopt­ysis, hematuria

• Diagnosis:

- Chest x-ray or high-r­eso­lution CT for respir­atory Ssx
- Vascular imaging (MRI, MRA, CTA, vascular US, PET) to detect large artery lesions in vasculitis cases
-Labs: CBC, kidney & liver function, ESR, serolo­gies, & urinalysis w/ urinary sediment

• Manage­ment:

- Long-term survival highly depends on the Dx, response to treatment, & adverse effects of drugs
- Managed w/ medication
- 3 main compon­ents: remission induction, remission mainte­nance, & monitoring

• RED

• Aetiology (risk factors):

- Global annual burden of VTE is in millions
- Signif­icant morbidity & mortality associated w/ VTE cases worldwide
- Majority of VTE cases are hospit­al-­related or acquired (60%)
- Leading preven­table cause of death in hospit­alised pts
- Risk factor: >40 yrs, obesity, varicose veins, immobi­lity, oral contra­cep­tive, smoking, hyperc­oag­ula­bility, pregnancy, & pelvic­/hi­p/l­ong­-bone fractures
- Disease states ↑ risk: malign­ancies, spinal cord injury, nephrotic s., congestive heart failure, IBD, & recent MI

• Clinical & physical findings of DVT:

- Unilateral limb px is a common complaint
- Physical signs may include swelling, warmth, & tenderness to touch
- Physical exam signs for DVT have low Dx yield

• Diagnosis:

- Chest radiography
- D-dimer assay
- US & serial US for DVT
- CTPA & VQ for PE

• Manage­ment:

- Treatment is based on associated conditions
- 1° tre­atment is antico­agu­lation