Chapter 20 The Knee

Menisci

- Poor blood supply, inner 1/3 avascular - Increases joint surface contact - Decreases friction - Increases joint stability

Medial Collateral Ligament (MCL)

- Prevents Valgus and external rotation - Attached to medial meniscus

Anterior Cruciate Ligament (ACL)

- Prevents tibia from anterior translation (sliding forward) on femur - Stabilizes tibia against interior rotation Valgus and Varus

Posterior Cruciate Ligament (PCL)

- Prevents tibia from posterior translation on femur - Prevents hyperextension

Lateral Collateral Ligament (LCL)

- Tight in extension - Prevents Varus movement

Sweep Manuever

Acts like memory foam

Bursittis

Acute, chronic, recurrent swelling Prepatellar - continued kneeling Infrapatellar - overuse of patellar tendon Signs and Symptoms - prepatellar bursitis may be localized swelling above knee that is ballotable - swelling in popliteal fossa may be a Baker's cyst (palpable, can cause pain in movement) Management: -eliminate cause RICE and NSAIDs - aspiration and steroid injection

Cruciate Ligaments

Anterior Cruciate Ligament (ACL) Posterior Cruciate Ligaments (PCL)

Larsen Johansson Disease

Apophysitis on inferior pole (apex) of patella - too much stress - begins cartilagenous and develops a bony callus, enlarging the tubercle - resolves with aging Signs and Symptoms - swelling - hemorrhaging - gradual degeneration of the apophysis due to impared circulation - pain with kneeling, jumping and running - point tenderness Management: - conservative -- reduce stressful activity until union occurs (6-12 months) -- possible casting, ice before and after activity -- isometrics for quadriceps and hamstrings

Osgood Schlatter Disease

Apophysitis on tibial tubercle - too much stress - begins cartilagenous and develops a bony callus, enlarging the tubercle - resolves with aging Signs and Symptoms - swelling - hemorrhaging - gradual degeneration of the apophysis due to impared circulation - pain with kneeling, jumping and running - point tenderness Management: - conservative -- reduce stressful activity until union occurs (6-12 months) -- possible casting, ice before and after activity -- isometrics for quadriceps and hamstrings

Pre-patellar Bursae

Between skin and patella

Superficial Infra-Patellar

Between tendon and skin

Deep Infra-Patellar

Between tendon and tibia

Genu Varus

Bow legged

Medial Meniscus

C-Shaped

Peroneal Nerve Contusion

Compression of peroneal nerve due to a direct blow Signs and Symptoms: - local pain and possible shooting pain - numbness and paresthesia in cutaneous distribution of nerve - added pressure may exacerbate condition - generally resolves quickly, in the event it does not resolve it could result in drop foot (consult doctor if it lasts more than 24 hours) Management: - RICE and return to play once symptoms resolve and no weakness is present - padding for fibular head is necessary for a few weeks

Acute Patella Subluxation/Dislocation

Deceleration with simultaneous cutting in opposite direction (valgus force at knee) - quad pulls the patella out of alignment - some athletes may be predisposed to injury - repetitive subluxation will stress medial restraints Sign and Symptoms: With subluxation, pain and swelling - restricted ROM - palpable tenderness over adductor tubercle - dislocation result in total loss of function

Chrondromalacia Patella Stage 3

Deformation of the surface of the articular cartilage caused by fragmentation

Patellar Fracture

Direct trauma - falling on it - forcible contraction, jumping or running Sign and Symptoms: - hemorrhaging, joint effusion, generalized swelling - indirect fractures may cause capsular tearing, separation of bone fragments and quadriceps tendon tearing Management: - surgery - immobilize for 2-3 months - significant rehabilitation - up to 1 year

Patella

Distributes compressive stress on the femur by increasing contat between patellar tendon and femur - Protects patellar tendon against friction - When moving from extension to flexion the patella glides laterall and further into trochlear groove

Chrondromalacia Patella Stage 2

Fissuring of the softened articular cartilage

Valgus force

Fracture lateral tibial plateau

Varus force

Fracture medial tibial plateau

Knee Flexors

Gastrocnemius Popliteus

Joint Effusion

Generalized swelling from joint

Posterior Cruciate Ligaments (PCL) Sprain

Greatest risk - fall with knee at 90 degrees of flexion - Dashboard injury -- fall on bent knee is most common mechanism - damaged as a result of a rotational force - not common in athletics Signs and Symptoms: - feel a pop in the back of the knee - tenderness and little swelling in the popliteal fossa - laxity with posterior sag test

Knee Musculature Flexors

Hamstings - Biceps femoris - Semitendinosus - Semimembranosus

Distal Femur and Proximal Tibia Fractures

High energy force applied - fracture for distal femur and tibial plateau -- varus force -- valgus force Sign and Symptoms: - pain and inability to bear weight immediately - swelling - deformity may be present with severe fracture - depending upon severity and displacement of fracture, partial ROM may be possible

Knee Plica

Irritation of plica (generally, mediopatellar plica and often associated with chondromalacia) Signs and Symptoms: - possible history of knee pain/injury - recurrent episodes of painful psuedo-locking (doesn't lock but feels like it) - possible snapping and popping - pain with stairs and squatting - little or no swelling and no ligamentous laxity

Patellar Tendinosis (Jumpers or Kickers Knee)

Jumping or kicking - stress and strain on patellar or quadricpes tendon - sudden or repetitive extension Signs and Symptoms: - pain and tenderness at inferior pole of patella - 3 phases -- pain after activity -- pain during activity -- pain during and after activity Management: - ice, phonophoresis, iontophoresis, ultrasound, heat - exercise - patellar tendon bracing/strap - transverse friction massage

Extracapsular swelling

Localizes over the injured structure - May migrate down to foot and ankle

Anterior Cruciate Ligament (ACL) Sprain

MOI - tibia externally rotated and valgus force at the knee - may be linked to inability to decelerate valgus and rotational stresses - landing strategies - extrinsic factors: conditioning, skill acquisition, playing style, equipment, preparation time - involve damage to other structures including meniscus, capsule, and MCL

ACL Sprain

Management: - MRI to diagnosis injury - could lead to major instability in incidence of high performance - without surgery joint degeneration may result - age and activity may factor into surgical option - surgery ma involve joint reconstruction with grafts -- 3-5 weeks of a brace -- also requires 4-6 months or longer of rehab

Posterior Cruciate Ligaments (PCL) Sprain

Management: - RICE - non-operative rehab of grade I and II injuries should focus on quad strength - surgical -- 6 weeks of immobilization in extension with full weight bearing on crutches -- ROM after 6 weeks and PRE at 4 months

Medial Collateral Ligament (MCL) Sprain Grade III

Management: - RICE - Conservative non-operative versus surgical approach - Limited immobilization with a brace - Progressive weight bearing and increased ROM over 4-6 week period - Rehab would be similar to Grade I and II injuries

Medial Collateral Ligament (MCL) Sprain Grade II

Management: - RICE for 48-72 hours; crutch use until acute phase has resolved - Brace/casting prior to initiation of ROM activities - Modalities 2-3 times daily for pain - Progression from isometrics (quad exercise) to CKC exercises - Function progression activities

Medial Collateral Ligament (MCL) Sprain Grade I

Management: - RICE for at least 24 hours - Crutches - Cryokinetics with exercise - From isometrics and Straight Leg Raises to bicycle riding and isokinetics - Return to play when all areas have returned to normal - 3 weeks to recover

Meniscal Lesions

Management: - Surgery removes damaged portions attempts to preserve the meniscus - Menisectomy -- removal/rehab allows partial weight bearinga nd quick return to activity - repaired meniscus will require immobilization, non-weight bearing and a gradual return to activity over teh course of 9-12 weeks

Osteochondral Knee Fractures

Management: - diagnosed through use of CT and MRI - treatment dependent on stability of fracture - rehabilitation is dependent on location of fracture - ROM is typically initatied early after surgery with active strengthening beginning after 6 weeks - return to activity at 3-6 months

Acute Patella Subluxation/Dislocation

Management: - reduction is performed by flexing hip, moving patella medially and slowly extending the knee - following reduction, immobilization for at least 4 weks with use of crutches and isometric exercises during this period - after immobilization period, horseshoe pad with elastic wrap on bracing should be used to suppor patella - muscle rehab focusing on muscle around the knee, thigh and hip are kep - Straight Leg Raises are optimal for the knee - possible surgery to release tight structures - improve postural and biomechanical factors

Collateral Ligaments

Medial Collateral Ligament (MCL) Lateral Collateral Ligament (LCL)

Menisci

Medial Meniscus Lateral Meniscus

Meniscal Lesions

Medial more commonly injured due to ligamentous attachments and decreased mobility -- prone to injury with torsional and valgus forces - most commonly injured with rotary force

Lateral Meniscus

Oval shaped - Needs more cartilage

Knee Musculature Extensors

Quadriceps: - Rectus Femoris - Vastus medialis - Vastus lateralis - Vastus intermedius Satorius

Bursae

Reduces friction - Pre-patellar - Superficial Infra-Patellar - Deep Infra-Patellar - Gastrocnemius

Pes Anserine Tendonitis or Bursitis (Cyclist's Knee)

Repetitive/overuse conditions - result of excessive genu valgum and weak vastus medialis - often occurs due to running with one leg higher than the other (running on a slope or crowned road) Signs and Symptoms - excessive genu valgum and weak vastus medialis - running with one leg higher than the other

IT Band Friction Syndrome (Runner's Knee)

Repetitive/overuse conditions - general expression for repetitive/overuse conditions attributed to mal-alignment and structural asymmetries Signs and Symptoms: - irritation at IT band's insertion - commonly with genu varum or hyperpronation Management: - myofascial release via foam roller

Patellofemoral Stress Syndrome

Result of lateral deviation of patella - tight structures, pronation, increased Q angle, insufficient medial musculature Signs and Symptoms: - tenderness of lateral facet of patella - swelling associated with irritation of synovium - dull ache in center of knee - patellar compression will elicit pain and crepitus Management: - correct imbalances (strength and flexibility) - taping and bracing - lateral retinacular release if conservative measures fail

Medial Collateral Ligament (MCL) Sprain Grade I

Result of severe lateral blow or outward twist Sign and Symptoms: - Little fiber tearing or stretching - stable valgus test - little or no join effusion - some joint stiffness and point tenderness - relatively normal ROM

Lateral Collateral Ligament (LCL) Sprain

Result of varus force with tibia internal rotation - direct blow is rare - if severe enough damage can also occur to the cruciate ligaments, ITB, and meniscus producing bony fragments as well

Osteochondral Knee Fractures

Same MOI as collateral/cruciate ligaments or meniscal injuries - twisting, sudden cutting or direct blow - fractures of cartilage and underlying bone varying in size and depth Signs and Symptoms: - Hear a snap and feeling of giving way - immediate swelling and considerable pain - diffuse, pain along joint line

Osteochondritis Dissecans

Separation of articular cartilage and subchondral bone - cause is unknown, may include blunt trauma, possible skeletal or hormone abnormalities Signs and Symptoms: - aching pain - recurrent swelling - locking - possible quadriceps atrophy and point tenderness Management: - rest and immobilization for children - surgery may be necessary in teenagers and adults

Ballotable Patella

Sign of joint effusion - Patella can be pressed down to feel fluid

Medial Collateral Ligament (MCL) Sprain Grade II

Signs and Symptoms - no gross instability - laxity at 5-15 degrees of flexion - swelling and pain along medial aspect of knee - moderate to severe joint tightness - decreased ROM

Medial Collateral Ligament (MCL) Sprain Grade III

Signs and Symptoms: - Complete tear of supporting ligaments - Complete loss of medial stability - Minimum to moderate swelling - Immediate pain followed by ache - Loss of motion due to effusion and hamstring guarding - Positive Valgus stress test (0 degrees)

Meniscal Lesions

Signs and Symptoms: - effusion developing over 48-72 hour period - joint line pain and loss of motion (medial vs. lateral) - intermittent locking and giving way - pain with squatting - portions may become detached causing locking, giving way, or catching within the joint - chronic --> recurrent swelling or muscle atrophy may occur

ACL Sprain

Signs and Symptoms: - experience pop with severe pain - disability --> can't bear weight - rapid swelling at the joint line - positive anterior drawer and lachman's - could lead to major instability

Lateral Collateral Ligament (LCL) Sprain

Signs and Symptoms: - pain and tenderness over LCL - swelling and effusion around the LCL - joint laxity with varus testing - may cause irritation of the peroneal nerve Management: - follows management of MCL injuries depending on severity

Chrondromalacia Patella

Softening and deterioration of the articular cartilage - exact cause unknown - abnormal patellar tracking may be a major factor Signs and Symptoms: - pain with walking, running, stairs, and squatting - possible recurrent swelling - grating sensation with flexion and extension - palpable pain at inferior border during PROM flexion/extension Management: - conservative measures -- RICE, NSAIDs, isometrics, orthotics to correct dysfunction - surgical possibilities -- altering muscle attachments -- shaping and smoothing of surfaces -- drilling -- elevating tibial tubercle

Patellar Tendon Rupture

Sudden, powerful quad contraction - does not occur unless a chronic inflammatory condition persists resulting in tissue degeneration - primary at point of attachment Signs and Symptoms: - palpable defect, lack of knee extension - considerable swelling and pain (initially) Management: - surgical repair is needed - proper care of jumpers knee minimizes occurrence

Chrondromalacia Patella Stage 1

Swelling - softening of articular cartilage

Hemarthrosis

Swelling within the joint that is caused by synovial fluid and blood

Genu Valgus

When standing up, knees are drawn medially - Forms an inverted Y shape

Genu Recurvatum

When standing up, knees are hyperextended - Looks like knees are bent backward