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