Miscellaneous 2 Flashcards
4 stages of bone healing
- Inflammation
- Soft callus
- Hard callus
- Remodeling
Inflammation
- Peaks at 48 hours, subsides at 1 week
- Inflammation acts as an immoblizer by causing pain and edema
4 days
Soft callus
- Begins several days after injury and persists for 1-2 months
- Fibrous and cartilagenous tissue develops at each end of the fracture
- If the soft callus fails to unite, the two sides of the fracture will cease to grow and will be resorbed
4 weeks
Hard callus
If a soft callus is successful in connecting the fracture, it begins to ossify
- This occurs at 2-4 months
4 weeks
Remodeling
- Lasts for several years
- Excessive callus is resorbed
- Final bone morphology is determined by Wolff’s law
4-ever
How long does it take for osteomyelitis to show up on x-ray?
2 weeks
Osteomyelitis takes about 2 weeks to show up on x-ray after there has been a 50% loss of bone
Sequestrum
A piece of necrotic bone separated from living bone by granulation tissue, radiographically evident as a highly opaque, smooth island of bone that is usually surrounded by areas of decreased bone density
Involucrum
A layer of living bone that has formed around the dead (infected) bone
Cloaca
An opening in the involucrum that may form a sinus and drain
Brodie’s abscess
A chronic abscess in bone surrounded by dense fibrous tissue and sclerotic bone, most commonly found in the metaphysis
Phases of wound healing
- Inflammatory phase
- Proliferative phase
- Remodeling phase
Inflammatory phase
- 1-7 days
- Influx of platelets and leukocytes
- Release of cytokines and mediators
- Coagulation
Proliferative phase
- 5-20 days
- Collagen fibers are produced and lend strength to wound
- Re-epithelialization (some authors describe epithelialization as a separate phase between proliferation and remodeling)
- Angiogenesis
- Fibroplasia
- Wound contraction
Remodeling phase
AKA maturation
- 3 weeks to 2 years
- Deposition of matrix materials
- Collagen deposition/remodeling
- Return to preinjury state
- As long as the scar or past ulcer site is erythematous, remodeling is occurring
Stages of Charcot
- Stage 0: Pre-Charcot
- Stage 1: Fragmentation/developmental
- Stage 2: Coalescence
- Stage 3: Remodeling/reconstruction
Stage 0
Pre-Charcot
- Warmth, dull pain, swelling and joint instability, with normal appearing bone and joints on radiographs
- Acute sprain or fracture in the presence of neuropathy
Stage 1
Fragmentation or developmental
- Clinical signs and symptoms of inflammation (warmth, erythema and edema)
- X-ray: bone debris formation at the articular margins, fragmentation of the subchondral bone, subluxation, dislocation and capsular distention
- Dissolution, fragmentation, dislocation
Stage 2
Coalesence
- Beginning of the reparative process
- Edema, warmth and redness diminish
- X-ray: absorption of fine debris and fusion of large fragments to adjacent bones, bone ends become sclerotic
Stage 3
Remodeling/reconstruction
- Bony consolidation and healing
- Residual bony deformity is common, most notably collapse of the longitudinal arch resulting in the classic “rocker-bottom” foot
- Rounding of the bone ends with a decrease in sclerosis
- Bony protuberences are clinically important because they may develop sites for future neuropathic pressure ulcers
HBO therapy
- Increases oxygen concentration in the blood
- Angiogenesis and fibroblast production occurs, which helps with collagen synthesis and epithelial closure
- During HBO treatment and for 3-4 HOURS AFTER the O2 is dissolved in the plasma and helps oxygenate the hypoxic area
- Speeds healing time for ulcerations
Baxter’s neuritis
- Entrapment neuropathy of the 1st branch of the lateral plantar nerve (AKA nerve to abductor digiti minimi muscle)
- Pain after activity rather than pain first thing in the morning as with plantar fasciitis
Pigmented villonodular synovitis
- Symptoms: pain, joint effusion, hemarthrosis (thus hemosiderin pigment), limited ROM
- The syovium will appear red-brown in color due to the hemosiderin found in the tissue
Post op note
SAPPPPA HEMI CG
S = Surgeion A = Assistant P = Pre-op diagnosis P = Post-op diagnosis P = Procedure P = Pathology A = Anesthesia
H = Hemostasis E = EBL M = Materials I = Injectables
C = Complications G = General statement about how the patient is doing
Admit orders
ADC VANDILMAX
A = Admit to service D = Diagnosis C = Condition (stable, fair, poor)
V = Vitals q8 hrs A = Activities N = Nursing orders D = Diet I/O = Ins and outs L = Labs M = Meds A = Ancillary services X = X-ray
Microcytic anemia
- Iron deficiency
- Thalassemia
- Blood loss
- Lead poisoning
Normocytic anemia
- Chronic disease
- Bone marrow failure
- Hemolysis
Macrocytic anemia
- Folate acid deficiency
- Vitamin B12 deficiency
- Liver disease
- Drugs (phenytoin, cytotoxic meds)
Normal INR
3-4
Therapeutic INR = 2-3
ANA (antinuclear antibody)
Normal: negative
Conditions with positive ANA:
- Lupus
- Scleroderma
- RA
- Sjogren’s
- Dermatomyositis
- Polyarteritis
RA factor (rheumatoid factor)
Absence of RA factor does not exclude diagnosis of RA
Positive in:
- Rheumatoid arthritis
- Systemic lupus erythematosus
- Scleroderma
- Dermatomyositis
- Sjogren’s syndrome
- Syphilis
- Sarcoidosis
- Liver disease
HLA-B27
Human leukocyte antigens (HLA) are a major histocompatibility antigen found on all nucleated cells, play a major role in histocompatibility between donors/recipients
Positive in: A = ankylosing spondylitis R = reactive arthritis (Reiter's) P = psoriatic arthritis E = enteric colitis (ulcerative colitis, regional enteritis)
ASA classification
I = healthy patient II = mild systemic disease III = severe systemic disease that limits activity IV = severe systemic disease with constant threat to life V = not expected to survive with or without surgery VI = brain dead, organ donation surgery
Pituitary adrenal suppression
Patients on 7.5 mg of corticosteroids/day should be tested for cortisol suppression
If regular dose <5 mg…
Continue regular dose with no supplementation
If regular dose >5mg…
Continue regular dose PLUS 25 mg supplementation prior to surgery
Tourniquet rules
- Inflate tourniquet to 100-120 over systolic
- Max for ankle = 250
- Max for thigh = 500
- Max time = 2 hours, must be deflated for 15-20 minutes before reinflating
Patients on anti-coagulants before surgery
- Discontinue 3-6 days prior to surgery and resume 24 hrs after surgery
- If anticoagulant cannot be stopped, discontinue coumadin 3 days prior and start heparin drip, DC heparin drip 2-4 hours prior to surgery
Pre-op rheumatoid patient
- Cervical spine x-ray due to predisposition for atlas/axis dislocation
- More prone to infection due to immunosuppressive medications
Sickle cell disease
- Mutationin beta chain gene that results in amino acid change from glutamic acid to valine
- Hemoglobin S becomes insoluble and aggregates into long strands in “sickle” shape
- Sickle cell can no longer deform in shape to fit through small capillaries and they can clog small vessels and result in ischemia
- Anemia due to spleen destroying all abnormal RBCs, resulting in splenomegaly
- Signs/sympoms: long bone pain, hand/foot pain, arthritis with fever, avascular necrosis of femoral head, chronic punched out lesions of ankles, abdominal pain with vomiting
Surgical considerations in sickle cell disease
- High index of suspicion for sepsis post-op
- Salmonella is most common organism from sickle cell patients with osteomyelitis
- Prone to hypoxia
- Local anesthesia preferred to prevent hypoxia
- Avoid tourniquet
- Increased post-op complications
- If using general, extra precautions must be taken to avoid volume depletion and hypoxia
Operative considerations for cardiac patients
- Delay elective surgery for 6 months after an MI
- Endocarditis prophylaxis for patients with valve disease, rheumatic murmur, prosthetic valves (IV PCN or ancef, clinda if PCN allergic)
- Patients on diuretics need K+ checked
- HTN (diastolic pressure of 110) increases intra op risk of MI or stroke
- Most heart medications should be continued up to and through the day of surgery
Post-op fever
- Wind: atelectasis (first 24-48 hours)
- Water: UTI (after day 3)
- Wound: infection (after day 5)
- Walking: DVT, PE (day 7-10)
- Wonder: anesthesia, drugs, other
Weakest point in a screw
Run out
Point where shank (non-threaded part) meets the threaded part
Pitch
Distance between threads
Cortical screws have smaller pitch than cancellous screws
Rake angle
Thread to axis of screw angle
Core diameter
Diameter of screw between the threads (not including threads)
Thread diameter
This value is used to describe the screw size (i.e. a 2.7 mm screw has a 2.7 mm thread diameter)
Tip angle
Tip to axis of screw angle
Mini frag set
1.5 and 2.0 cortical screws
Small frag set
2.7 and 3.5 cortical screws, 4.0 cancellous screws (partially or fully threaded)
Standard or large frag set
4.5 cortical screws, 4.5 malleolar screws and 6.5 cancellous screws
Lag by technique
- Drill thread hole (2.0 mm drill bit, drill through near and far cortex) - over drill
- Drill glide hole (2.7 mm drill bit, drill through near cortex only) - under drill
- Countersink
- Measure
- Tap (2.7 mm tap)
- Flush
- Insert 2.7 mm screw (to two finger tightness)
Tension band wiring
- Used when there is eccentric distraction of fracture/osteotomy site due to muscle/ligament pull
- Converts distractive forces into compressive forces
- Cerclage wire placed on tension side of osteotomy prevents distraction and cause compression on opposite side
- Common uses: patellar, malleolar and styloid process fractures
Dynamic compressive plate
Allows compression across a fracture/osteotomy site as screws are tightened due to plate screw hole shape
Neutralization plate
Allows stress to be transmitted through the plate so as to avoid the fracture/osteotomy site
Buttressing plate
Used to maintain separation of bone to protect a bone graft from being crushed
Tension band plate
- As with tension band wiring, it takes advantage of asymmetrical biomechanical forces across a fracture/osteotomy site
- The plate is placed on teh tension side of a fracture/osteotomy to prevent distraction on that side, causing corresponding compression on the other side
Ilizarov
A technique to heal non-unions involving an external fixation device
Through variations of this technique, the bone can also be elongated by as much as 1 mm/day through slow distraction
Primary pathogen that infects implants
Staphylococcus epidermis
