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Lower Extremity Sports Injuries

I. Patellofemoral pain syndrome (chondrosis, chondromalacia patella [CMP1)

A. General considerations

1. Most common PFJ problem and most common cause of knee pain, overall

2. Overuse >> traumatic

3. Malalignment common etiology.

4. Females.

B. Common mechanism of injury

1. Direct impact

2. Twisting injury

3. Overuse

4. Inflexibility or ligamentous laxity

C. History

1. Anterior knee pain with activity.

2. Climbing, kneeling, bending, sitting.

3. Catching, grinding, giving way.

4. Pain with prolonged sitting and getting out of a seated position "movie sign"

D. Physical findings

1. PFJ crepitans with active knee extension


3. Quadriceps (Q) angle >17E

4. Tightness to ITB or lateral retinaculum

5. Generalized ligamentous laxity

6. Foot and hip abnormality

E. Diagnostic studies

1. X-rays: Axial view (merchant or sunrise); DX: alignment, DJD, OCD

2. MRI: not very helpful

F. Differential diagnosis

1. Lateral retinacular compression

2. Plica

3. ITB syndrome

4. Excessive femoral anteversion

5. Pes Planus

6. Osgood-Schlatter disease

7. Sinding-Larsen Johansson syndrome

8. Patella fracture

9. Patella instability or subluxation

G. Treatment

1. Relieve pain: rest, or activity modification, NSAIDs, patellar sleeve or taping, corticosteroid injury, for DJD.

2. Restore strength: exercise program, PT, 3-6 months.

3. Gradual return to sports.

F. Referral

1. Poor response to above treatment.

2. Any effusion.

G. Natural history

1. >70% improve with rehabilitation alone

2. Life time commitment

3. Most have good days and bad days

H. Surgery

1. Arthroscopic debridement for failure of conservative tx. (min. 3 mos.).

2. Lateral release for malalignment issues

3. Tibial tubercle elevation for failed debridement or malalignment adjustment

4 Cartilage transplant - osteoarticular transplant

5. Patellectomy last resort

I. Treatment success

1. 70-80% improve with non operative treatment

2. Surgery only helps another 70-80%

3. Arthroscopic debridement usually not long lasting

4. Traumatic chondromalacia better surgical results than atraumatic

5 .Cartilage transplantation successful results 80-90%

J. Length of rehabilitation

1. At least 2 months

2. life style modification necessary

II. Other common patellofemoral problems

A. Patellar instability: dislocation vs. Subluxation

1. History

a. Dislocation

1) Distinct episode: contact or non contact

2) "Knee went out': may reduce spontaneously

3) (+) pain, swelling (hematoma)

b. Subluxation

1) Sudden pain, giving way, collapse

2) "Feels weak" +/- effusion

2. Physical findings

a. Both: effusion (hemarthrosis); TTP medial facet, VMO, adductor tubercle

b. (+) Patellar Apprehension Test: more common with dislocation

c. Dislocation: palpable defect in medial patellar retinaculum

3. Diagnostics

a. X-rays

1) axial view at 300 flexion (merchant or sunrise view)

2) Evaluate position - subluxed or tilted

3) Fracture or OCD

b. CT scan

1) Single 30 degree of flexion view

4. Differential diagnosis

a. Lateral retinacular compression

b. Plica

c. ITB Syndrome

d. Excessive femoral anteversion

e. Pes Planus

f. Osgood-Schlatter disease

g. Sinding-Larsen-Johansson syndrome

h. Patella fracture

5. Recurrence: if <20 yrs old

6. Treatment: similar for dislocation and subluxation

a. Reduce if necessary; ice, NSAIDS, patellar sleeve "horseshoe brace" to limit lateral subluxation

b. Physical therapy: quad rehabilitation, McConnoll taping

7. Referral

a. Irreducible dislocations

b. Subluxations that fail rehabilitation (recurrent symptoms)

8. Surgery: stabilize and realign

a. For recurrence, despite adequate rehabilitation

b. Release tight lateral patellar retinaculum; (+/-) repair and tighten lax medial retinaculum; (+/-) Realign distal patellar tendon insertion (tib tubercle)

B. Prepatellar bursitis

1. History: direct trauma or prolonged/repetitive kneeling

2. Exam: bursa swollen, boggy, tender (extra-articular), (-) intra articular effusion, R/O infection (septic bursitis): red, warm, tender

3. Treatment: Ice, NSAIDS, avoidance/protection (pad, etc.)

4. Refer: Resistant, recurrent or infected bursitis

5. Surgery: Drain septic bursitis; occasionally need to excise entire bursa

C. Chondral fracture

1. History: Trauma

2. Exam: Crepitus in PFJ with active knee extension (step-up test)

3. Treatment: Ice, NSAIDS, rehabilitation; avoid crepitant arc of motion

4. Refer: continued symptoms despite adequate rehabilitation

5. Diagnostics: arthroscopy

6. Surgery: arthroscopic debridement (smoothing); cartilage transplantation

III. Tendon and muscle injuries

A. General considerations

1. Age dependent

a. Adolescents - physeal injuries young adults - ligament, muscle and tendon injuries older adults - bone, tendon and muscle injuries

B. Common injury mechanisms

1. Excessive stretch

a. Active - direct stretch

b. Passive - over contraction of antagonistic muscles

2. Failure at muscular tendinous injury or within weakened substance of the tendon

C. History

1. Pain, swelling, pseudoparalysis

2. Acute sharp pain with post injury inability to active move joint

D. Physical examination

1. Tenderness

2. Palpable defect

3. Loss of active motion

4. Moderate swelling, +/- ecchymosis

E. Diagnostic studies

1. Plain X-ray

a. Rule out fracture or avulsion

2. MRI

a. Rarely necessary

b. Useful in diagnostic dilemma cases

F. Differential diagnosis

1. Contusion

2. Muscle rupture

3. Avulsion injuries

4. Tendon ruptures

5. Nerve injuries

G. Treatment

1. Minimize swelling

2. Stabilize limb

3. Pain management

4. Tendon rupture - surgery

5. Musculotendinous injuries - rehabilitation

H. Referral

1. Tendon rupture

2. Persistent Tendinitis without Improvement

I. Natural history

1. Muscle injuries

a. Injuries heal with scar and then contract

b. May develop recurrence if immature scar is stressed

2. Tendon ruptures

a. Complete ruptures

1) Need surgical repair to prevent shortening of musculotendinous unit

b. Partial tendon ruptures

1) No surgery if full function against resistance

2) May complete rupture in the future

J. Surgery

1. Direct repair

2. Tendon transfer - reconstructive

K. Length of rehabilitation

1. Muscle tears

a. may require up to I month of immobilization to heal

b. 1-2 month of further rehab to stretch and strengthening

2. Tendon ruptures - after repair

a. Cast immobilization - 1-2 months

b. Protective brace mobilization - 1 month

c. Begin strengthening - 1-2 months

d. No resistive strengthening until 6-8 weeks

e. 3 months until return to activities

L. Examples

1. Hamstring strains

a. Very long musculotendinous portion - tears can happen anywhere

b. Avulsion fractures of ischial tuberosity may need to be fixed surgically if a significant portion is involved

c. Takes any extremely long time to heal

2. Quadriceps strains/contusions

a. Strains usually near the knee

b. Tears >40 years of age

c. Contusions - bleeding within the muscle may form calcifications - myositis ossificans (do not biopsy)

d. Faster return to sport if initially treat muscle injury on stretch (quads - flex knee, hams - extend knee)

3. Hip pointer - greater trochanteric bursitis

a. Rubbing iliotibial band over greater trochanter

b. Most pain with hip flexion and extension

c. Good result with injection and physical therapy

4. Groin pull

a. Adductor longus strain occasionally gracious

b. Long recuperation time (crossed hip and knee)

c. Preconditioning and stretching

5. Iliotibial band friction syndrome

a. Rub of ITB over lateral epicondyle of femur

b. Pain with knee flexion and extension

c. NSAIDs/injection and physical therapy

6. Patella tendinitis/rupture

a. Jumper's knee

b. Rupture <40 years of age

c. Chronic injuries associated with mucoid degeneration

7. Pes anserinus bursitis anterior medial knee pain below the joint line NSAIDs and physical therapy

IV. Anterior leg pain - (compartment syndrome, shin splints (periostitis), and stress fracture)

A. Compartment syndrome

1. General considerations

a. Present with anterior leg pain

b. Acute versus chronic (exercise induced)

c. Elevated tissue pressure within a closed fascial space

d. Reduced capillary blood perfusion and compromised neuromuscular function

2. Common mechanism of injury - etiology

a. Ischemia-(inflow or outflow problems)

b. Trauma - contusion versus fracture

c. Swelling - muscle rupture

d. Increased interstitial fluid pressure

e. Exercise- overuse

f. Circumferential burns

g. Crush injuries

3. Pathophysiology

a. Edema

b. Muscle necrosis

c. Nerve compression - degeneration

d. Muscle regeneration or fibrous tissue replacement

e. Contracture deformity - muscle or nerve

4. Anatomy

a. Four compartments

1) Lateral

2) Anterior

3) Superficial posterior

4) Deep posterior

5. Symptoms

a. Pain

b. Pallor

c. Pulselessness

d. Paresthesia

e. Stretch Pain

f. Hypoesthesia

g. Tenderness

h. Tenseness

6. Physical findings

a. Swelling

b. Pain to palpation

c. Pain with passive or active muscle stretch


Injury Pathophysiology Physical Exam Treatment Technique Pitfalls
Patellar tendon rupture <40 years old

Eccentric loading

Sharp, distinct, acute pain

Palpable defect

No active extension

Surgery Midline approach

Debride mucoid tissue and frayed

Inadequate repair

Patella infera ends

Patellar tendinitis Repetitive eccentric loading activities

Gradual onset

Localized swelling 

Pain with resistive extension




Physical therapy

Debride unhealed lesion

Reinforce tendon

Inadequate debridement

Weaken tendon

Secondary rupture

surgery if failed treatment

Osgood-Schlatter disease Adolescent or preteen

Tibial tubercle apophysis or avulsion

Local tenderness

Ossicle may be present



Cast if severe

Surgery if tubercle avulsion or adult with painful ossicle

  Damage to tendon
Sinding-Larsen-Johansson syndrome Adolescent or preteen

Inferior patellar pole

Local tenderness

Pain with resistive extension



Cast if severe

Surgery if patellar occlusion or adult with painful ossicle

Midline approach

Shell out ossicle


Damage to tendon
Quadriceps tendon rupture >40 years old

Eccentric loading

Systemic disease or degenerative joint disease

Sharp sever pain

Palpable defect

No active extension

Surgery Midline approach

Repair retinaculum

Debride defect

Evaluate intra-articular extent

Intra-articular damage