Surgery 4 Flashcards

(138 cards)

1
Q

Presentation of gastric cancer?

A
Persistent epigastric pain, worse with eating (irritant effects of gastric acid on the tumor)
Weight loss (insufficient calorie intake)

If proximal -> may cause dysphagia, N/V

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2
Q

Dx gastric cancer?

A

EGD (visualize the stomach and obtain biopsy samples of suspicious lesions

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3
Q

Risk factors for gastric cancer?

A

H. pylori infection, smoking, alcohol use, atrophic gastritis, diets rich in salt-preserved foods and nitroso compounds (Eastern Asia, Eastern Europe, Andean South America)

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4
Q

What is used to diagnose gastroparesis?

A

Gastric emptying scan

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5
Q

What is the most common carpal bone fracture?

A

Scaphoid

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6
Q

Typical cause of scaphoid fracture?

A

Falls onto an outstretched hand that cause axial compression or wrist hyperextension

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7
Q

The arterial supply to the scaphoid from the ___ artery enters through foramina in the bone’s distal pole before proceeding to the proximal pole; fracture can disrupt flow to the proximal segment, leading to ___ and ___.

A

Radial; avascular necrosis; non-union

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8
Q

Presentation of scaphoid fracture?

A

Tenderness in the anatomic snuffbox (high sensitivity for fracture, warrants evaluation with imaging)

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9
Q

Boundaries of the anatomic snuffbox?

A

Tendon of the extensor pollicus longus (medially)

Tendons of the abductor pollicis longus and extensor pollicus brevis (laterally)

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10
Q

Work-up of suspected scahpoid fracture?

A

Initial x-rays (low sensitivity)
If negative -> CT or MRI of wrist to confirm OR immobilize wrist briefly in a thumb spica splint with repeat XR in 7-10 days

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11
Q

Patients who have a delayed presentation of appendicitis with a longer duration of symptoms (>5 days) often have ___.

A

Appendiceal rupture with a contained abscess

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12
Q

How can appendiceal abscess be identified on physical exam?

A

Use maneuvers that assess the deep abdominal spaces (psoas sign, obturator sign, etc.)

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13
Q

Treatment of appendiceal abscess?

A

If clinically stable, manage with IV ABX and hydration, bowel rest, and possible percutaneous drainage of the abscess, then elective appendectomy in 6-8 weeks

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14
Q

Risk factors for bleeding while on warfarin?

A

DM, age>60, HTN, alcohol use, supratherapeutic INR

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15
Q

Classic triad of renal cellc arcinoma?

A

Hematuria, abdominal mass, flank pain

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16
Q

Define complicated diverticulitis.

A

Associated with abscess, perforation, obstruction, or fistula formation

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17
Q

Management of complicated diverticulitis with a fluid collection?

A

If <3 cm -> IV ABX and observation
If >3cm -> CT-guided percutaneous drainage
If symptoms not controlled by day 5, surgical drainage and debridement

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18
Q

Who gets sigmoid resection in the setting of diverticulitis?

A

Fistulas, perforation with peritonitis, obstruction, recurrent attacks

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19
Q

Presentation of testicular cancer?

A

15-35 y/o
Risk factors include a family history, cryptorchidism
Unilateral painless testicular mass
Dull ache in lower abdomen

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20
Q

Types of testicular cancer?

A

Germ cell tumors (95%): seminomatous or non-seminomatous (embryonal carcinoma, yolk sac, choriocarcinoma, teratoma, mixed)

Sex cord-stromal tumors: Sertoli cell, Leydig cell

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21
Q

Dx testicular cancer?

A

Exam: firm, ovoid mass within the tunica albuginea
Elevated tumor markers: AFP, beta-hCG, LDH
Scrotal U/S -> solid, hypoechoic lesion (seminoma) or lesion with cystic areas and calcifications (non-seminomatous germ cell tumor)

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22
Q

Rx testicular cancer?

A

Radical inguinal orchiectomy (confirm dx histologically, definitive treatment)

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23
Q

Risk factors for stress fracture?

A
Repetitive activities (running, gymnastics, etc.)
Abrupt increase in physical activity
Inadequate calcium and vitamin D intake
Decreased caloric intake
Female athlete triad: low caloric intake, hypomenorrhea/amenorrhea, low bone density
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24
Q

Presentation of stress fracture?

A

Insidious onset of localized sub-acute pain
Point tenderness at fracture site
Possible negative XR in the first 6 weeks

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25
Management of stress fracture?
Reduced weight bearing for 4-6 weeks | Referral to ortho for fracture at high risk for malunion (eg, anterior tibial cortex, 5th metatarsal)
26
Most commonly involved metatarsal - stress fracture?
Second metatarsal
27
Initial management of uncomplicated hemorrhoids?
Increased intake of fluid and fiber Reduction in fat and alcohol intake Regular exercise Limit time sitting on toilet, limit defecation to 1x daily, avoid straining Topicals: analgesics (benzocaine, etc.), astringents (eg, witch hazel), hydrocortisone
28
High risk features for colorectal cancer?
Prior adenomatous colon polyps Age 50+ (unless negative colonoscopy within the last 2-3 years) Age 40-49 with a first-degree relative with colorectal cancer at age <60 Familial colon cancer syndrome
29
Management of gallstones without symptoms?
No treatment necessary in most patients
30
Management of gallstones with typical biliary colic symptoms?
Elective laparoscopic cholecystectomy Possible ursodeoxycholic acid in poor surgical candidates
31
Management of complicated gallstone disease (acute cholecystitis, choledocholithiasis, gallstone pancreatitis)
Cholecystectomy within 72 hours
32
In the setting of blunt abdominal trauma, what can spill into the peritoneal cavity and cause acute chemical peritonitis? How does it present?
Blood, bowel contents, bile, pancreatic secretions, urine Diffuse abdominal pain and guarding; may present with referred pain to the ipsilateral shoulder (Kehr sign)
33
What is the dome of the bladder?
Superior and lateral surfaces, bordered by the peritoneal cavity
34
What causes bladder rupture after blunt trauma?
Sudden increase in intravesical pressure, most likely following a blow to the lower abdomen when the bladder is full and distended
35
Which portions of the bladder are extraperitoneal vs. intraperitoneal?
Extra - anterior bladder wall, bladder neck Intra - bladder dome
36
What leads to tear in the anterior bladder wall and neck and how does it present?
Pelvic fracture; localized lower abdominal pain 2/2 extraperitoneal leakage of urine
37
Most common site of urethral injury?
Bulbomembranous junction (junction of anterior and posterior urethra)
38
Presentation of anterior urethral injury?
Penile trauma is often visible
39
Presentation of posterior urethral injury and bulbomembranous transection?
High-riding prostate on digital rectal exam
40
Presentation of testicular torsion?
``` Adolescents (most common) Testicular, inguinal, abdominal pain N/V Horizontal testicular lie with elevated testicle Absent cremasteric reflex Swollen, erythematous scortum ```
41
Imaging of testicular torsion?
Doppler U/S - no blood flow on scrotal U/S Heterogenous echotexture - late finding indicating necrosis (develops after >12 hours)
42
Management of testicular torsion?
Surgical detorsion and fixation with exploration of the contralateral side Manual detorsion if immediate surgery is not available
43
Presentation of bladder cancer?
Older adults Cigarette smoke or exposure to chemical carcinogens Painless hematuria, voiding symptoms (dysuria, frequency, etc.), hydronephrosis (obstruction by tumor) with flank pain Possible elevated creatinine
44
Work-up of suspected bladder cancer? When should this be done?
Urgent urinary cystoscopy to visualize the bladder wall and biopsy suspicious masses Abdominal CT for staging Adults >40 with painless hematuria, no evidence of infection, GN, or nephrolith
45
In older men with BPH (may have hematuria, chronic voiding symptoms) who develop acute urinary tract obstruction (typically bilateral hydronephrosis), what should be done?
Decompression with a Foley catheter
46
Why are hematuria and acute urinary retention rare in prostate cancer?
Because most tumors form in the periphery of the prostate, not in the periurethral zone
47
DDx - acute abdominal/pelvic pain in women (5)
1. Mittelschmerz 2. Ectopic pregnancy 3. Ovarian torsion 4. Ruptured ovarian cyst 5. PID
48
U/S findings of these 5 diagnoses?
1. Mittelschmerz - not indicated 2. Ectopic pregnancy - no intrauterine pregnancy 3. Ovarian torsion - enlarged ovary with decreased or absent blood flow 4. Ruptured ovarian cyst - pelvic free fluid 5. PID - +/- tubo-ovarian abscess
49
Presentation of Mittelschmerz?
Recurrent mild and unilateral mid-cycle pain prior to ovulation Pain lasts hours to days
50
Presentation of ectopic pregnancy?
Amenorrhea, abdominal/pelvic pain and vaginal bleeding | + beta-hCG
51
Presentation of ovarian torsion?
Sudden-onset, severe, unilateral lower abdominal pain, N/V | Unilateral, tender adnexal mass on examination
52
Presentation of ruptured ovarian cyst?
Sudden-onset, severe, unilateral lower abdominal pain immediately following strenuous or sexual activity
53
Presentation of PID?
Fever/chills, vaginal discharge, lower abdominal pain, cervical motion tenderness
54
Although hemoperitoneum does not typically occur with ovarian cyst rupture, it can present in certain patients - ?
Patients on anticoagulation
55
Rx of unstable patient with hemoperitoneum 2/2 ruptured ovarian cyst?
Surgery to stop the bleeding
56
Femoral nerve innervation (motor and cutaneous)?
Motor - leg flexion at the hip, leg extension at the knee, patellar reflex Cutaneous - anterior thigh (anterior cutaneous branches), medial leg (saphenous branch)
57
Femoral nerve injury can occur in what settings?
Pelvic fracture, hip dislocation, hematoma Iatrogenic during prolonged dorsal lithotomy position, vascular procedures involving the femoral artery or vein
58
Common peroneal nerve injury can occur in what setting?
Fracture or compression at the proximal fibula?
59
Innervation by the common peroneal nerve?
Posterolateral leg and dorsolateral foot Footdrop 2/2 weakness of foot eversion, dorsiflexion, toe extension
60
Ilioinguinal nerve injury can occur in what setting?
Pelvic or hernia surgery
61
Innervation by the ilioinguinal nerve?
Sensory to the upper medial thigh and genital region
62
Innervation by the obturator nerve?
Medial compartment of the thigh -> weak hip adduction, decreased sensation at the medial thigh
63
Innervation by the tibial nerve?
Injury at the popliteal fossa - weak plantar flexion 2/2 denervation of the gastrocnemius and soleus Compression as it passes under the flexor retinaculum in the medial side of the ankle - numbness and paresthesias in the sole and distal toes
64
Work-up following initial endoscopy/biopsy + for gastric adenocarcinoma?
1. CT A&P (staging, sensitive for mets) 2. PET/CT, endoscopic U/S, laparoscopy, CT chest, +/- paracentesis/peritoneal lavage. If limited stage -> surgical resection If advanced stage -> chemo +/- palliative surgery
65
Pre-hospital management of cervical spine trauma?
1. Spine immobilization (backboard, rigid cervical collar, lateral head supports, etc.) 2. Careful helmet removal 3. Airway oxygenation
66
ED management of cervical spine trauma?
1. Orotracheal intubation preferred unless significant facial trauma present 2. Rapid-sequence intubation added for unconscious patients who are breathing but need ventilatory support 3. In-line cervical stabilization suggested unless it interfere with intubation 4. CT of entire cervical spine 5. Monitoring of neurogenic shock from spinal cord injury
67
Purpose of laryngeal mask placement?
Temporary measure to stabilize the patient until another airway can be established if orotracheal intubation fails
68
When is nasotracheal intubation contraindicated?
Apneic/hypopneic patients | Basilar skull fracture
69
Why is needle cricothyroidotomy not ideal in patients with head injury?
They may need hyperventilation to prevent or treat intracranial hyperventilation
70
When is needle cricothyroidotomy preferred to surgical?
Children age <12 (easier to perform anatomically)
71
Common causes of steatorrhea (categories)?
1. Pancreatic insufficiency 2. Bile salt-related 3. Impaired intestinal surface epithelium
72
Causes of pancreatic insufficiency?
1. Chronic pancreatitis (2/2 alcohol abuse, CF, AI/hereditary) 2. Pancreatic cancer
73
Causes of bile salt-related steatorrhea?
1. Small-bowel Crohn disease 2. Bacterial overgrowth 3. Primary biliary cirrhosis 4. Primary sclerosing cholangitis 5. Surgical resection of the ileum (at least 60-100 cm)
74
Causes of impaired intestinal surface epithelium?
1. Celiac disease 2. AIDS enteropathy 3. Giardiasis
75
3 rare causes of steatorrhea?
1. Whipple disease 2. Zollinger-Elison syndrome 3. Medication-induced
76
Presentation of fat malabsorption?
Weight loss | Loose, greasy, malodorous stools that float in the toilet and are difficult to flush
77
Rx chronic pancreatitis 2/2 alcohol use?
Alcohol cessation | Pancreatic enzyme supplementation
78
Patient with C6 paraplegia, severe HTN, flushing, diaphoresis, and bradycardia in the setting of urinary retention - this presentation suggests what? Explain the mechanism.
Autonomic dysreflexia, a potentially life-threatening complication of spinal cord injury above T6 In an intact spinal cord, sympathetic activity is modulated by higher-level neurons; however, SCI results in loss of modluatory activity below the lesion Noxious stimuli can precipitate an unregulated sympathetic response, leading to vasoconstriction and severe hypertension. Above the lesion, a compensatory parasympathetic response causes diaphoresis, flushing, bradycardia, and nasal congestion. Vasodilation occurs but cannot overcome the sympathetic drive to normalize systemic pressure.
79
Complications of autonomic dysreflexia?
Intracranial hemorrhage, progressive bradycardia with cardiac arrest
80
Management of autonomic dysreflexia?
Close monitoring of BP Upright position to encourage orthostatic BP reduction Search for precipitating events Tight-fitting clothes should be removed Evaluate for urinary retention, fecal impaction, pressure sores Short-duration antihypertensives may be indicated
81
Cause and presentation of carotid sinus hypersensitivity?
Significant drops in HR (i.e., pauses) and BP (>50 mm Hg) following carotid massage Lightheadedness or syncope after carotid manipulation in older patients with atherosclerotic disease
82
How is ankle-brachial index caculated?
Divide the higher ankle (dorsalis pedis/posterior tibial) systolic pressure in each lower extremity by the higher brachial artery (left or right) systolic pressure
83
Interpret ABI
0. 90 or less: abnormal, dx occlusive PAD 0. 91-1.30 - normal 1. 30+ suggestive of calcified and uncompressible vessels; additional vascular studies should be considered
84
When is routine one-time screening for AAA indicated?
Men age 65-75 with a smoking history
85
What is the role of arterial U/S in diagnosing PAD?
Non-invasive, can be used to localize the site and severity of vascular obstruction Less sensitive and specific than ABI for initial diagnosis Generally performed in symptomatic patients with abnormal ABI who are being considered for interventional procedures
86
Threshold for post-operative fever?
>38 C (100.4 F)
87
Categories of post-operative fever by timing?
1. Immediate (0-2 hours) 2. Acute (1-7 days) 3. Sub-acute (1 week to 1 month) 4. Delayed (>1 month)
88
Causes of immediate post-operative fever?
1. Tissue trauma 2. Blood products 3. Malignant hyperthermia
89
Causes of acute post-operative fever?
1. Nosocomial infections 2. SSI (GAS or C. perfringens) 3. Non-infectious (MI, PE, DVT)
90
Causes of subacute post-operative fever?
1. SSI (other organisms that are not GAS or C. perfringens)/catheter site infection 2. C. difficile 3. Drug fever (1-2 weeks after starting the drug) 4. PE/DVT
91
Causes of delayed post-operative fever?
1. Viral infections | 2. SSI (indolent organisms)
92
Most frequent cause of bloodstream infection in patients with intravascular devices?
Staph epidermidis (coag-negative)
93
List some factors suggesting infection instead of contamination.
1. Systemic signs (fever, hypotension, leukocytosis) 2. Erythema and tenderness at the catheter entry site 3. Culture growth within 48 hours and in both aerobic and anaerobic bottles 4. 2+ blood culture samples with the same organisms and drug susceptibility
94
Drugs that are associated with drug fever?
Anticonvulsants Antibiotics (beta-lactams, sulfonamides) Allopurinol
95
The patient with acute-onset severe abdominal pain, fever, tachycardia, and signs of peritonitis likely has ___.
Perforated viscus
96
Dx GI perforation?
Upright X-ray of the chest and abdomen -> free intraperitoneal air under the diaphragm
97
The patient with a history of retinoblastoma and a lytic bone lesion in the distal femur with "sunburst" periosteal reaction (concentric layers of reactive bone) likely has ___.
Osteosarcoma
98
Risk of osteosarcoma is greatest in those with what inherited genetic mutations?
Mutations of the tumor suppressor genes RB1 (hereditary retinoblastoma) and TP53 (Li Fraumeni syndrome)
99
How does osteosarcoma present in adults?
Older (>60), areas of previous bone damage due to Paget disease (most common), irradiation, or benign bone tumors
100
What is a Brodie abscess?
Form of chronic osteomyelitis that typically occurs in the femoral or tibial metaphysis in the second decade of life.
101
How does Brodie abscess appear on X-ray?
Radiolucent elongated lesion with surrounding reactive sclerosis
102
How does Langerhans cell histiocytosis present?
Rare disorder, children <3 y/o | Single or multiple "punched-out"lytic bone lesions
103
What is myositis ossificans and how does it appear?
Develop at the site of muscle injury; eggshell-appearing periosteal reaction around the area of injury
104
3 characteristic XR findings of OA?
Joint space narrowing, subchondral sclerosis, and osteophyte formation
105
What are unicameral bone cysts and how do they appear on XR?
Simple bone cysts occurring in individuals <20 y/o Full-thickness lytic bone lesion with well-defined (not irregular) borders and surrounding reactive sclerosis
106
Walk through the diagnosis of hypercalcemia, starting with an abnormal lab value.
1. Confirm hypercalcemia (repeat testing, correct for albumin concentration or measure ionized Ca) 2. Measure PTH level
107
If the PTH level is high-normal or elevated, what does this mean?
PTH-dependent cause DDx - primary or tertiary hyperparathyroidism Familial hypocalciuric hypercalcemia Lithium
108
If the PTH level is suppressed, what does this mean and what else should be done?
PTH-independent cause 1. Measure PTHrP, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D
109
DDx - PTH-independent hypercalcemia?
1. Malignancy 2. Vitamin D toxicity 3. Granulomatous diseases 4. Drug-induced (eg, thiazides) 5. Milk-alkali syndrome 6. Thyrotoxicosis 7. Vitamin A toxicity 8. Immobilization
110
Calculate corrected calcium
= measured calcium +[0.8(4 - albumin)]
111
Pathogenesis of hypercalcemia of immobilization?
Increased osteoclastic bone resorption; onset around 4 weeks after immobilization
112
Rx hypercalcemia of immobilization?
Bisphosphonates - inhibit osteoclastic bone resorption, effective in treating and reducing associated bone loss
113
Why do you need to correct calcium with respect to albumin?
~40% of circulating calcium is bound to proteins (predominantly albumin). Thus, hypoalbuminemia will lower the total serum calcium level. Measured calcium levels are corrected upward based on the extent of hypoalbuminemia. Conversely, hyperalbuminemia is associated with increased total calcium.
114
Unlike blunt abdominal or thoracic trauma, blunt genitourinary trauma is rarely life-threatening unless the kidneys or renal vasculature are involved. However, due to their retropertioneal location and the protection afforded by the ribs, these structures are infrequently injured in BGT. When injury does occur, what are the most common renal lesions?
Contusions, lacerations, renovascular injuries (eg, pedicle avulsion, renal artery dissection)
115
Evaluation of BGT?
Focused genitourinary exam in addition to evaluation for abdominal or thoracic trauma UA Hemodynamically stable patients with evidence of hematuria -> further imaging with a contrast-enhanced CT scan If unstable -> IV pyelography prior to surgical eval
116
List the 3 categories of IV fluids.
1. Isotonic 2. Hypotonic 3. Hypertonic
117
List the 3 types of isotonic IV fluids.
1. 0.9% (normal) saline 2. Lactated Ringer solution 3. Albumin (5% or 25%)
118
List the 3 types of hypotonic IV fluids.
1. Dextrose 5% in water 2. 0.45% (half-normal) saline 3. Dextrose 5% in 0.45% (half-normal saline)
119
List the 1 type of hypertonic IV fluid.
1. 3% (hypertonic) saline
120
Which IV fluid is colloid (the rest are crystalloid)?
Albumin
121
What is the effect of dextrose 5% in water and in 0.45% half-normal saline?
Both become markedly hypotonic due to metabolic of glucose (initially slightly hypotonic and hypertonic, respectively)
122
Fluids indicated in volume resuscitation (hypovolemia, shock, etc.)?
0.9% NS LR solution Albumin
123
Fluids indicated in treatment of SBP or hepatorenal syndrome?
Albumin
124
Fluids indicated in free-water deficit?
D5 in water | 0.45% half-normal saline
125
Fluids indicated in maintenance hydration?
D5 in 0.45% saline
126
Fluids indiated in severe, symptomatic hyponatremia?
3% saline
127
Fluid management in patients with extensive burns?
Aggressive fluid resuscitation to maintain tissue perfusion and reduce mortality Isotonic cyrstalloid solution with a similar osmolality to blood (~288 mOsm/kg H2O) -> LR, NS
128
Why is LR preferred for resuscitation in burn victim?
It contains near-physiologic levels of chloride, potassium, and calcium and includes sodium lactate, a buffer that is hepatically metabolized to bicarbonate, which helps correct acidosis and maintain normal blood pH.
129
Why is NS considered an unbalanced fluid?
Its chloride concnetration is supraphysiologic (154 vs 103) and can cause a hyperchloremia metabolic acidosis; also associated with hypocoagulability
130
Post-operative encephalopathy is most commonly associated with what type of surgery?
Cardiac
131
Where do most pancreatic cancers occur?
Head of the pancreas
132
Presentation of pancreatic cancer in the head of the pancreas?
Weight loss, painless jaundice, non-tender distended gallbladder on exam (Courvoisier sign) Imaging - intra- and extrahepatic biliary tract dilatio
133
Presentation of acute portal-vein thrombosis vs. chronic?
Acute - gradual or sudden-onset abdominal pain Chronic - variceal bleeding
134
Risk factors for plantar fasciitis?
Pes planus Obesity Working or exercising on hard surfaces (high-impact exercise, extendd time in bare feet)
135
Symptoms of plantar fasciitis?
Pain at plantar aspect of heel and hindfoot | Worse with weight bearing especially after prolonged rest
136
Dx plantar fasciitis?
Tenderness at insertion of plantar fascia | Pain with dorsiflexion of toes
137
Rx plantar fasciitis?
Activity modification Stretching exercises Heel pads/orthotics
138
Pathophysiology of plantar fasciitis?
Inflammation and degeneration of the plantar aponeurosis (deep plantar fascia), a thick, fibrous band that extends from the calcaneus to the toes and supports the longtiduinal arch of the foot; thought to be due to chronic overuse and repetitive microtrauma