Musculoskeletal Diseases of the Lower Extremity

Remo George, Ph.D., ABSNM, NMTCB(CNMT)

TopicsSkeletal Disorders: • Disorders of the Joints of the Lower Limb

– Osteoarthritis– Disorders of the Hip Joint

• Avascular Necrosis• Legg-Calvé-Perthes Disease• Slipped Capital Femoral Epiphysis• Hip Dislocation• Labral Injuries• Impingement Syndromes

• Disorders of the Knee Joint – Knee Ligament Injuries– Meniscal Injuries– Osteochondral Lesions (Osteochondritis

Dissecans)– Prepatellar Bursitis

• Disorders of the Ankle and Subtalar Joints – Sprains – Osteochondral Lesions of the Ankle – Miscellaneous Disorders of the Ankle and Foot

• Morton Interdigital Neuroma, Metatarsalgia, and Sesamoiditis

• Bone Injuries of the Lower Limb – Stress Reactions and Stress Fractures

Muscle Disorders:• Disorders of Muscle-Tendon Groups of the

Lower Limb– Disorders of the Iliotibial Band, Including

Trochanteric Bursitis– Disorders of the Hamstring Muscle Group– Disorders of the Adductor Muscle Group– Pes Anserine Tendonitis or Bursitis

• Injuries to the Quadriceps Muscle Group– Patellar Tendinopathy– Osgood-Schlatter Disease and Sinding-Larsen-

Johansson Disease– Quadriceps Strain, and Quadriceps and Patella

Tendon Rupture– Rectus Femoris Avulsion from the Anterior

Inferior Iliac Spine– Quadriceps Contusions and Myositis Ossificans

• Injuries to the Anterior Leg Muscle Group– Tibialis Anterior, Extensor Hallucis Longus, and

Extensor Digitorum Longus• Injuries to the Posterior Leg Muscle Group and

Associated Soft Tissue Structures– Gastrocnemius, Soleus, Tibialis Posterior, Flexor

Hallucis Longus, and Flexor Digitorum Longus– Sever Disease– Flexor Hallucis Longus Overload– Tibialis Posterior Overload or Medial Tibial Stress

Syndrome• Injuries to the Lateral Leg Muscle Group

– Compartment Syndrome• Injury to the Plantar Foot Muscles and Plantar

Fascia– Plantar Fasciitis

Disorders of the Iliotibial Band: Including Trochanteric Bursitis

• Symptoms: Pain on rising up from sitting, pain to lie on

• Bursa irritated between femoral trochanter and gluteus medius/iliotibial tract

• Trauma/hip Sx/ repetitive movement/spontaneous

• Tenderness over gt. Trochanter

• Female:Male= 4:1. Incidence 2/1000

• Tx: injection/NSAID/PT Focal increased uptake of 99mTc-MDP in left greater

trochanteric region compatible with bursitis (arrow)

Disorders of the Hamstring Muscle Group

• Muscle overload– challenged with a sudden load– stretched beyond it’s limit

• Muscle gets stretched too far• Seen in running sports:

– football, basket ball, soccer, runners, dancers, young athletes still growing

• Signs/symptoms: swelling, tenderness, bruising/ discoloration

• Ischial avulsion injury possible Ischial avulsion fracture (arrow). A 17-year-old

female cheerleader who had sudden onset of buttock pain with a high-kicking maneuver.

Disorders of the Adductor Muscle Group

• Groin strain: – from acute or repetitive

overload – sudden twinge or tearing – pain, weakness, and internal

hemorrhaging• Usually adductor longus injury• Avulsion fractures of inferior

pubic ramus possible• Causes: running, jumping,

twisting with hip external rotation, over-stretching/too forceful contraction

• Tx: RICE (rest, ice, compression, elevation) therapy, NSAIDs

MRI of the thighs, showing a tear of the left adductor muscle group in a hockey player.

99mTc-MDP muscle uptake. Significant injury due to weight lifting damage in adductor muscle groups of medial thighs (arrow). Biochemical evidence of elevated muscle enzymes was also present.

Combined Muscle Group InjuryPes Anserine Tendonitis or Bursitis

• Anteromedial knee pain, occasional swelling

• Acute inflammation of:– one or more of three

conjoined tendons near their insertion (tendonitis)

– Bursa lying 2 inches below the medial knee joint (bursitis)

• Causes: overuse/ friction (from valgus, flatfoot, rotatory stresses, direct contusion)

• Tx: Ice, NSAIDS, steroid inj.

NM imaging of blood-pool showing hyperemia of synovial lining (pes anserine bursitis) and bony lateral tibial plateau. Arrow points to bursitis. (B) MRI shows large joint effusion and anserine bursitis (arrow) in same medial area of knee as in A.

J. Nucl. Med. Technol. June 2007 vol. 35 no. 2 64-76

Injuries to the Quadriceps Muscle GroupPatellar Tendinopathy (Jumper’s knee)

• Pain usually at the inferior pole of patella

• Patellar tendon overload from repetitive knee flexion and extension

• At risk: basketball players, volleyball players, bicyclists, rowers, mogul skiers, baseball catches, supermarket shelf stockers, carpenters, and carpet layers.

• Tx: RICE, NSAIDs, Rehab

MRI showing patellar tendonitis. The pale area indicates inflammation and swelling.

Chronic patella tendinitis. Triathlete with long history of

recurrent pain in the proximal left tibia in

spite of multiple corticosteroid injections. The

SPECT/CT images demonstrate schlerosis

of the tibial tubercle and calcification of the

adjacent patella tendon in the CT

images (arrowheads) with intense uptake at

both sites.

Injuries to the Quadriceps Muscle GroupOsgood-Schlatter Disease (OSD)/

Sinding-Larsen-Johansson Disease (SLJD) • More common in older

children/ young adults• Repetitive overload at

the patella tendon insertion at the tibial tuberosity (OSD), or at the origin of the patella tendon at the inferior pole of the patella (SLJD)

• Significant pain, tenderness, inflammation, or partial avulsions of the tibial tuberosity (in OSD)

J Nuc Med 28:1768-1770,1

a: Normal lateral 99mTc-MDP blood-pool image of right knee, b: Lateral blood-pool image of the left knee with abnormalities (arrows) corresponding to the inferior patellar border and tibial tuberosity (left knee).

Injuries to the Quadriceps Muscle GroupQuadriceps Strain, and Quadriceps & Patella Tendon Rupture

• Injury following forceful quadriceps contraction with foot planted

• “unstable knee”• Anterior knee

swelling• Unable to extend

knee– Patella will move up

for PTR, but will not move for QTR

• Palpable defect proximal or distal to patella

• Tx: knee immobilizer, crutches, and Sx MRI showing Normal (L); Quadriceps tendon rupture (R)

Lateral radiograph of the knee, showing an abnormally

highriding patella after an acute patella tendon rupture. The patient was a 40-yearoldairline pilot who described

“landing a little aft of center” while alpine skiing. A sudden

forceful quadriceps contraction while attempting to regain balance resulted in

this injury.

Injuries to the Quadriceps Muscle GroupRectus Femoris Avulsion from the Anterior Inferior Iliac Spine

• Pain at front of the hip• occur most often in young• Possible from forceful

contraction of rectus femoris

• RICE, NSAIDs, Rehab, Sx (if > 3cm separation)

http://gamma.wustl.edu/bs137te144.html

Injuries to the Quadriceps Muscle GroupQuadriceps Contusions and Myositis Ossificans

• From direct & forceful trauma to front of thigh

• Ant. thigh pain, stiffness, tenderness, ecchymosis, swelling, antalgic gait

• Intramuscular hematoma calcific transformation myositis ossificans (quads – most common site)

A bone scintigram (A) shows marked accumulation of radiotracer in the region of Rt. Hip. Plain radiograph (B) of Rt. Hip shows ossification in soft tissues.

Injuries to the Anterior Leg Muscle GroupTibialis Anterior, Extensor Hallucis Longus, and

Extensor Digitorum Longus

• Overload injuries less common

• Overload of tibialis anterior – eg. down hill running– Pain in muscle belly, or

musculotendinous junction, or anteromedial midfoot tendon insertion site

This 57 year-old male experienced spontaneous pain in medial side of left foot. SPECT/CT helped enable a diagnosis of tibialis anterior tendinosis and enthesopathy and also calcaneocuboidal artrosis.

Injuries to the Posterior Leg Muscle Group and Associated Soft Tissue Structures

Achilles Tendon Issues• Achilles tendon (AT) overload is

common• Chronic: swollen, nodular, & tender AT

(tendinitis), with collagen breakdown & microscopic tearing (tendinosis)

• Acute: sudden, powerful eccentric force (eg. basketball) rupture of AT (audiable pop)

• RICE, Sx if needed, rehab Bilateral Achilles tendinopathy. Intense uptake around the Achilles tendons with associated bursitis (arrowheads)

Injuries to the Posterior Leg Muscle Group and Associated Soft Tissue Structures

Sever Disease

• Traction apophysitis of Achilles tendon insertion on posterior calcaneus

• Seen in active adolescents during rapid growth (bones lengthen, muscles tight)

• Exacerbated with activities and improved with rest

• Calcaneal pain, tight gastrocnemius-soleus

• Tx: ice, rest, brace, rehab

Injuries to the Posterior Leg Muscle Group and Associated Soft Tissue Structures

Shin Splints(Anterior/ Medial Tibial Stress Syndrome)

• Common in runners, dancers and military recruits

• overload dysfunction of:– tibialis anterior, extensor

digitorum longus and extensor hallucis longus (anterolateral shin splint)

– tibialis posterior, medial gastrocnemius, or medial soleus (posteromedial shin splint)

• Bone overload persistant stress periostitis tibial stress fracture

Injuries to the Lateral Leg Muscle Group

Compartment Syndrome• Pressure within a muscle

compartment (95% cases in lateral/ant) is abnormally elevated causing ischemia

• Causes: – Acute: trauma (eg.

fracture, crush injury); can cause permanent muscle damage; surgical emergency

– Chronic: occurs in runners, military recruits; lower limb affected; pathophysiology poorly understood (↑muscle relaxation pressure ischemia); Tx with NSAIDs, Rest

99mTc-MDP bone imaging showing compartmental syndrome in a patient following lithotomy position for 6 hours. Urine bag & catheter (closed arrows)

Clinical Nuclear Medicine Vol 38, Number 5, May 2013

Rhabdomyolysis Associated with Compartment Syndrome

Injury to the Plantar Foot Muscles and Plantar Fascia; Plantar Fasciitis

• A.k.a plantar heel pain syndrome

• Painful inflammatory process of plantar fascia; pain in volar heel, esp. 1st few steps in morning

• Overload injury due to biomechanical issues (ankle lean inward, flat foot), repetitive trauma (15-20% runners affected)

Skeletal Disorders

Osteoarthritis• Etiology/Risk

Factors: Age, Trauma, Genes

• Pathogenesis: Progressive EROSION of articular cartilage

• Morphology: X-Ray, “eburnation”, “joint mice”, osteophytes

• Clinical Expression: PAIN, Limitation of motion

Heberden’s Nodes in DIP

Osteoarthritis

Nature:BoneKEy Reports, 2012, (1)136

• Cause: ISCHEMIA– Trauma– Steroids– Thrombus/Embolism– Alcohol abuse– Vessel injury, e.g., radiation– Sickle cell anemia– INCREASED intra-osseous

pressure vascular compression

– Venous hypertension

Disorders of the Hip Joint

Avascular Necrosis

Disorders of the Hip Joint

Legg-Calvé-Perthes Disease• Idiopathic osteonecrosis of femoral head • Occurs in children, typically boys 4-10yr• Bilateral 10% • Prognosis better if onset < 6yrs, ↑rates of

hip dysfunction into early adulthood if older• Wait-and-watch, braces, Sx (osteotomy),

rehab

Legg-Calvé-Perthes disease. A, (top row) Scintigrams by standard parallel-hole collimator fail to reveal the abnormality. Pinhole images of the same patient (bottom row) reveal the characteristic lentiform area of decreased uptake on the left. B, Corresponding radiograph obtained months later reveals deformity of the left femoral epiphysis with flattening, increased density and increased distance between the epiphysis and the acetabulum.

Disorders of the Hip JointSlipped Capital Femoral Epiphysis

• Displacement of capital femoral epiphysis from metaphysis (20 to disruption of physis in the immature hip

• Cause: acute trauma/ repetitive microtrauma, obesity

• Most common hip disorder in adolescent (8-15y), boys > girls

Pediatric Nuclear Medicine edited by S.T. Treves; P262

Disorders of the Hip JointHip Dislocation

• Requires significant trauma• Dislocation > fractures in

children• Posterior dislocation (presents

with hip flexion, internal rotation and adduction) > anterior dislocation (hip extension, external rotation, abduction, & acetabular fx)

• Needs closed reduction under anesthesia, or Sx

• Concern for sciatic nerve injury, osteoarthritis, AVN in 10% pts.

• Injury from acute or repetitive trauma, hypermobility, dysplasia

• Groin pain, clicking of hip

• MRI arthrography with intraarticular contrast is best imaging for Dx

• Tx: PT, NSAIDs, rest, intraarticular steroid shot, arthroscopic debridement/repair

Disorders of the Hip JointLabral Injuries

Examples of labral tears. (A) “Eyebrow” pattern of uptake corresponding to an anterosuperior labral tear (arrowhead). There is also a femoral head osteochondral fracture (arrow) in association with the steep acetabular angle of hip dysplasia. (B) “Eyebrow” pattern of uptake of an anterosuperior labral tear. (C) Focal uptake in a tear of the superior labrum.Clinical Nuclear Medicine • Volume 29, Number 8, August 2004

• Morphological variations of acetabulum/femoral head resulting in mechanical damage to joint

• Groin pain, limited ROM, DJD

• 2 types:– CAM: bump @

femoral head-neck jn.– Pincer: acetabular

over-coverage of femur head

• Tx: PT, NSAIDs, Sx

Disorders of the Hip Joint

Impingement Syndromes

Hip impingement. Increasing right hip pain in a motocross bike rider which worsened after a number of falls. Hyperemia (arrowhead in BP) and intense uptake around the right hip (arrowhead in delay) with the SPECT/CT image showing the site of impingement between the anterior-superior acetabulum and lateral femoral head (arrowheads)

Disorders of the Knee Joint

Knee Ligament Injuries

• MCL & ACL injuries - most common

• MCL: valgus sprain medial pain, swelling but no joint effusion– Tx: ice, elevation, knee

immobilizer, rehad• ACL: most functional

impairment in sprains; twisting knee injury; “pop” sound; joint effusion possible; Segond fx (lat. tibial plateau avulsion)– Tx: ice, elevation, compression,

knee brace, rehab• PCL: Less common, seen in

soccer, dashboard injuries

Segond fx

Anterior bone scintigraphy demonstrates a large intense lesion in the left lateral tibial plateau which was confirmed on MRI. The less intense lesion in the lateral femoral condyle was not seen on MRI. The faint but definite focal uptake peripherally in the medial femoral condyle (arrow head) was an avulsion of the insertion of the medial collateral ligament on MRI and confirmed at surgery. The classic triad of avulsion of the medial collateral ligament with opposite “kissing” lesions laterally is obvious on scintigraphy. Knowledge of this type of injury facilitates scintigraphic diagnosis, however, avulsion injuries could be misreported as fractures.

Disorders of the Knee Joint Meniscal Injuries

• Common; can be acute or chronic

• Acute tear: from sudden twisting motion

• Symptoms: pain, swelling, clicking;

• Bucket handle tear flipped up into intercondylar notch locked knee

• Tx: ice, elevation, NSAIDs, brace

Medial meniscus tear. This was a surgically proven injury in a patient being assessed for patella tendinitis. The SPECT/CT study shows a region of intense uptake and sclerosis in the mid-body of the crescent of the medial meniscal subchondral bone (arrowheads) in keeping with a tear of the meniscus and adverse remodeling of the underlying tissues.

Disorders of the Knee Joint

Osteochondritis Dissecans

• Mostly in 10-15yr olds• Lesion in subchondral bone (lat. aspect of

medial femoral condyle) progresses through stages to overlying articular cartilage Grade 4 complete avulsion of osteochondral fragment & dislocation

• Mechanism unknown, causative factors may be genetic/ vascular/ trauma

• Symptoms: recurrent pain & swelling (worse with stress, better with rest)

• Tx: Rest, Sx

A B

Disorders of the Knee Joint Prepatellar Bursitis

• A.k.a “carpet layer's knee”/ “nun’s knee”

• Associated with kneeling for extended time

• Swelling & pain anterior to patella

• Tx: RICE therapy to swelling & pain, aspiration & steroid inj., Sx (rare)

Disorders of the Ankle and Subtalar Joints

Sprains• Most common MSK injury of leg (25% of all

sports injuries); predisposing factor: previous sprain

• Inversion/lateral ankle sprain of ant. talofibular ligament (weakest, most common), eversion (deltoid, uncommon), Syndesmotic high-ankle sprain (uncommon, severe)

• Small (Gr-I) to partial (Gr-II) to full tear (Gr-III)• Diffuse pain, swelling, hematoma

discoloration possible• Tx: RICE, brace, rehab

Partial avulsion fracture

after sprain

Am J Nucl Med Mol Imaging 2015;5(4):305-316

Disorders of the Ankle and Subtalar Joints

Osteochondral Lesions of Ankle• Causes: sprains, trauma• Deep ankle pain, worse with

activity, better with rest• Can affect medial talus

(usually from inversion, less severe, heals spontaneously) or lateral talus (forced eversion, more severe, difficult to self-heal)

• Rehab, Sx if severe

osteochondral lesion (arrow) in the inferior

posterior talus

J Nuc Med 32:2241-2244

(OCTDF = osteochondral talar dome fractures)

Disorders of the Ankle and Foot Morton Interdigital Neuroma, Metatarsalgia, and Sesamoiditis

• Similar presentations (Diff. Dx challenging)• Morton’s neuroma: irritation of an interdigital foot nerve

(b/w 3rd & 4th metatarsal head most common) leading to pain (“pebble in shoes”), worse with metatarsal (MT) head, interdigital nerve loading (eg. high heels)

• Metatarsalgia: Pain coming from metatarsal heads (instead from b/w heads), 2nd head pain most common, from overload of MT heads (running, toe walking, high heels)

• Sesamoiditis: Pain in 1st MT head following sesamoid bone injury

• Bone scans, MRI helful for Dx• Tx: Unloading of forefoot (large toe box shoe, avoid high

heels, gel insoles for wt. distribution Am J Nucl Med Mol Imaging 2015;5(4):305-316

Stress Reactions and Stress Fractures

• Repetitive overload injury to bone• Stress response ( bone remodeling) stress reaction (maladaptive areas w/ resorption > deposition) stress Fx (hairline break)

• Causes: Female athlete triad (disordered eating, amenorrhea, osteopenia), pes cavus, pes planus, leg length discrepancy, Q-angle, improper shoe fit/ cushion

• Tx: ice, rest, NSAIDs, image non-healing > 6 wk (bone scans very sensitive, MRI good for grading)

• Prevention: strengthen muscles ( strain on bone)