JAAOS lists Flashcards
When can bisphosphonates be considered? (6)
- Vertebral compression fracture with Osteoporosis
- Fragility fracture with osteoporosis
- Pagets
- MM
- OI
- AVN
- metastic disease (reduces skeletal events)
What are contributing factors to squeaking seen not only in COC but also MOM? (5)
- component malposition
- edge loading
- impingement
- third-body particles
- loss of lubrication
How does improper acetabular component orientation affect outcome of THA? (8)
- Increases dislocation rates
- component impingement
- Increased bearing surface wear
- Increased number of revision surgeries
- Leg length discrepancy increases
- Alteration of hip biomechanics
- Increased pelvic osteolysis
- Increased risk of acetabular component migration
What are the 5 moderate strength recommendations concerning distal radius fractures?
- Recommendations for surgical treatment
- Dorsal angulation >10 degrees
- shortening >3mm
- step off >2mm
- use a real cast for non op
- give vitamin c.
Fracture displacement in calcanei fractures typically results in these findings which can be problematic if malunion occurs. (5)
Loss of hindfoot height
Varus heel position,
Widening of the hindfoot
Possible subfibular impingement
Irritation of the peroneal tendon and/or sural nerve
What is the sole strong recommendation concerning vertebral osteoporotic compression fracture?
Don’t do a vertebroplasty.
4 complications of lateral humeral condyle fracture
- Cubitus valgus
- Tardy ulnar palsy
- Fishtail (due to osteonecrosis)
- Cubitus varus
Who wants to know the 4 moderate grade recommendations concerning RTC?
- NSAIDS and physio for incomplete tears
- No routine acromioplasty
- Don’t use xenograft patches
- Workers comp will do worse
What are the “most recognized” complications of TEA? (6)
- implant loosening
- periprosthetic fracture
- implant failure
- infection
- triceps insufficiency
- nerve palsy
List 8 complications of rTSA
- neurologic injury
- periprosthetic fracture
- hematoma
- infection
- scapular notching
- dislocation
- mechanical baseplate failure
- acromial fracture
List three distinct pathological types of knee osteonecrosis.
- secondary ON
- spontaneous ON of the knee
- postarthroscopic ON
4 indications for an HTO of in a varus knee
- varus alignment of the knee associated with medial compartment arthrosis
- knee instability
- medial compartment overload following meniscectomy
- osteochondral defects requiring resurfacing procedures
Concerning healed in situ pinning of SCFE, a proportion of these patients progress to symptomatic femoral acetabular impingement. List 3 surgical treatment options.
- arthroscopic femoral neck osteochondroplasty
- a limited anterior hip approach or surgical hip dislocation
- flexion intertrochanteric osteotomy
Concerning arthroscopic release of arthrofibrosis of the knee what four areas do you want to address?
- the anterior interval
- posterior capsule
- peripatellar
- suprapatellar regions
List contraindications to TAR (7)
uncorrectable deformity
severe osteoporosis
talus osteonecrosis
charcot joint
ankle instability obesity
young laborers increase the risk of failure and revision
List factors contributing to chronic ankle instability
Mechanical Pathologic laxity
Arthrokinetic restriction
Synovial changes
Degenerative changes
Functional Impaired
proprioception Impaired
neuromuscular control Impaired
postural control
Strength deficits
List 5 risk factors for progression of sponylolisthesis (5)
>50% slip
>50 deg slip angle
dysplastic
young age
female
Risk factors of pseudoarthrosis of sponylolisthesis (6)
Sacral slope > 45 deg
Hypermobile
L5/S1 Decompression
Sacral dysplasia
Spina bifida
Secondary changes of S1 from slip
Risk factors for child abuse (8)
low income
unemployed
single parent homes
abuse of parents
drug abuse
recent job loss of parent
children with disabilities (cerebral palsy, premature)
step children
Poor prognostic factors with Ewings
Location - spine and pelvic tumors (distal tumors have a better prognosis)
Size - tumors greater than 100cm3 or >8cm
Age >14 yo
Male
LDH >200IU
CRP/WBC elevation may be associted with mets and higher tumor burden
< 95% necrosis with chemotherapy
p53 mutation in addition to t(11:22) translocation
Relapse at < 2years
Complications of radiotherapy in a young person (5)
fragility fractures
limb length discrepancy
joint contracture
muscle atrophy
pathological fractures secondary malignancy (sarcoma, usually at 10 years, 20% will develop by 20 years)
Indications for immediate surgical fixation SCH# (8)
Open fracture
Dysvascular limb
Skin puckering
Floating elbow
Median nerve palsy
Evolving compartment syndrome
Young age
Cognitive disability
Surgical indications for disci tis (6)
◦ abcess ◦ neurologic deficits (for any reason) ◦ progressive deformity ◦ gross spinal instability ◦ persistent infection despite antibiotic (BW still elevated)
Indications for medical treatment of a spinal epidural abcess
◦ no neurologic deficits ◦ small abscess ◦ patient capable of close clinical follow-up ◦ those who are not candidates for surgery due to medical comorbidities
Contraindications for limb salvage procedure (7)
◦ Major neurovascular structures encased by tumor when vascular bypass is not feasible ◦ Pathologic fracture with hematoma violating compartment boundary ◦ Inappropriately performed biopsy or biopsy-site complications ◦ Severe infection in the surgical field ◦ Immature skeletal age with predicted leg-length discrepancy >8 cm ◦ Extensive muscle or soft-tissue involvement ◦ Poor response to preoperative chemotherapy
Indication to get c-spine imaging for a RA patient (5)
◦ Cervical symptoms > 6 months ◦ neurological signs ◦ procedure and no imaging 2 years ◦ rapid deterioration in function ◦ rapid deterioration of carpal and tarsal bones
Indications for surgical fixation of an RA spine (8)
◦ progressive neurological deficit ◦ pain refractory to medication ◦ radiographic risk factors for neurological injury ◦ PADI < 14mm with AAI ◦ odontoid migration > 5mm above magregor’s line ◦ Canal diameter < 14mm in SAS ◦ AAI or cord stenosis ◦ cervicomedullary angle 135
Radiographic features of enchondroma vs low grade chondrosarcoma on plain radiographs (8)
◦ Low grade features Dense calcifications with rings and spiclues Uniform calcification Eccentric, lobular growth of soft tissue ◦ High grade features Faint, amorphous calcification Large noncalcified areas Lysis within a previously calcified area Concentric growth of soft tissue mass
Clinical and radiographic features of MHE conversion to chondrosarcoma (4)
◦ acute onset of pain ◦ Adults with growing osteosarcoma ◦ Average age is 31 ◦ Cartilage cap > 2cm
Indications for fusion of first MTP in hallux valgus
Gout Rheumatoid arthritis Down’s syndrome cerebral palsy Severe DJD Ehler-Danlos Resection arthroplasty
Conditions that arise as a result of ulnar positive variance (5)
ulnar abutment syndrome SLD TFCC tears arthrosis ulnar head lunate triquetrum lunotriquetral ligament tears
4 cuts of a PAO
anterior ischium below the acetabulum superior pubic ramus supra-acetabular ilium posterior column
Important factors in healing a diabetic ulcer (5)
albumin > 3.0 g/dl lymphocyte > 1000 mm3 transcutaneous oxygen > 30mmHg - gold standard ABI > 0.45 toe pressure > 40mmHg
The most common wrist extensors that get injured during wrist arthroscopy
EDM EDC
Optimal position for knee arthrodesis
5-8° valgus 0-10° of external rotation (match other leg) 0-15° of flexion some limb shortening advantageous for patient self-care Can remove flexion if > 2cm LLD If > 4cm LLD should perform lengthening
Indications for hip arthrodesis
salvage for failed THA (most common) young active laborers with painful unilateral ankylosis after infection or trauma neuropathic arthropathy tumor resection
Indications for surgical treatment of first time shoulder dislocators
-
Absolute
- Associated Injury
- >50% rotator cuff tear
- Glenoid osseous defect >25%
- Humeral head articular surface osseous defect >25%
- Proximal humerus fracture requiring surgery
- Irreducible dislocation
- Interposed tissue or nonconcentric reduction
- Failed trial of rehabilitation
- Inability to tolerate shoulder restrictions
- Inability to perform sport-specific drills without instability
-
Relative
- >2 shoulder dislocations during the season
- Overhead or throwing athletes Contact sport athletes
- Injury near the end of the season Age <20 years
List reasons to consider leaving a well-fixed shell in place in the context of THA revision for retroacetabular osteolysis (5).
(JAAOS Stulberg et al. 2008)
- Area of osteolysis safely accessible for grafting
- Area of cup fixation is unaffected by the osteolysis.
- Cup is in good position
- Locking mechanism intact
- New poly liner is readily available.
Name 3 ideal conditions for cementing a new liner into existing shell during THA revision.
JAAOS Stulberg et al 2008
- Well fixed shell
- Presence of holes in the shell
- Shell is of sufficient diameter to allow new liner and >2mm cement mantle
List three scenarios when isolated polyethylene liner exchange is indicated in TKR revision.
JAAOS Dennis et al 2008
- Late revision for poly wear in patient with tibial and femoral components that are well fixed and well aligned.
- Patient with CR knee that develops PCL insufficiency. Can revise to dished (highly congruent) liner to substitute for PCL.
- Patient with varus/valgus ligamentous laxity. Can release the concave side to balance knee, and insert new thicker poly.
Name three scenarios where isolated femoral component revision in TKR is indicated.
JAAOS Dennis et al 2008
- CR develops PCL insufficiency, can revise femur to PS design with new PS poly insert.
- Isolated femoral component malrotation leading to asymmetric flexion instability.
- CR/PS knee develops MCL insufficiency. Can revise femur to CCK and insert new CCK liner. (If tibial component well fixed/aligned)
List 5 ideal chemical/pharmacologic prerequisites for an antibiotic that is to be used in a cement spacer.
***Bonus*** What is the minimum dose of antibiotic to be used per 40g of cement?
JAAOS Jacobs et al 2009
- Thermostable
- Broad spectrum
- Bacteriocidal at low dose
- Powder form with low serum binding potential, ie. water soluble.
- Low allergenicity
Bonus: 3.6 g of antibiotic per 40g of cement. Good choices are tobra, vanco or gent. Cephalosporins generally not used as they are not thermostable.
Two modes of wear in TKR tibial bearing insert.
Lachiewicz JAAOS 2011
- Fatigue damage (ie. pitting and delamination)
- Mechanical wear (adhesive and abrasive wear)
Principles of converting a fused hip to THA (6)
JAAOS Swanson et al 2011
- Identify and preserve abductors.
- Restore anatomic hip centre.
- Concentrically ream acetabulum
- Avoid cephalic cup position
- Restore native offset
- Achieve leg length equality
List 5 features of RA that are associated with higher likelihood of requiring hip or knee arthroplasty.
JAAOS Goodman et al 2013
- Onset of disease at younger age
- Positive RF
- Presence of rheumatoid nodules
- Erosive radiographic changes
- Poor functional status
- Persistent elevation of ESR & CRP
3 indications for preop referral to spine surgeon prior to elective surgery in RA patient
JAAOS Goodman et al 2013
- Presence of basilar invagination
- Instability leading to SAC <13mm
- Clinical myelopathy
What are the MSIS criteria for diagnosis of periprosthetic joint infection?
JAAOS Kuzyk et al 2014
- Sinus tract communication to the implant, OR:
- Two positive microbial fluid or tissue cultures, OR:
- Four of the six:
- ESR >30 and CRP >10
- Synovial WBC >1100 (knee) or >3000 (hip)
- Neutrophil % >64 (knee) or >80 (hip)
- Purulence in joint
- Single positive synovial fluid or joint tissue culture
- >5PMN per hpf in 5 hpfs @ x400 magnification
Blood management strategies prior to arthroplasty
(Preop, intraop, postop)
JAAOS Levine et al 2014
Preop
- Vitamin supplementation (Iron, folate, B12)
- EPO (indicated if preop Hb <130 or BW <50kg)
- Preop autologous donation (probably best for patients with normal preop Hb but expected blood loss such as revision or bilateral arthroplasties)
Intraop
- Acute normovolemic hemodilution (taking blood intraop and replacing with colloid - reduces concentration and number of RBCs lost)
- Tourniquet
- Bipolar sealant cautery
- Argon beam coagulation
- Antifibrinolytics (ie. TXA which blocks plasmin binding sites on fibrin, preventing fibrinolysis)
- Topical hemostatic agents (collagen/cellulose based, fibrin sealants)
Postop
- Reinfusion systems
- More stringent tranfusion protocols (Transfuse if Hb<60 & don’t transfuse if >80. If Hb 60-80 should evaluate for ongoing losses, symptoms, cardiovascular risk)
Swedish registry data shows that 30% of Vancouver B1 periprosthetic fractures treated with ORIF go on to fail vs. 18.5% failure of B2 fractures treated with revision arthroplasty. This suggests likely misclassification of B2s as B1s. List methods of determining implant stability.
JAAOS Shah et al 2014
- History of groin/thigh pain, startup pain, etc. before inciting trauma.
- Imaging: lucent lines, subsidence, pedestal, etc.
- Intraop: Stability at bone-implant interface in fracture site. Alternatively, can open and dislocate hip to assess for stem stability.
Risk factors for extensor mechanism disruption after TKR:
JAAOS Bates et al 2015
Multiply operated knee
DM
Renal disease
RA
Obesity
What are 8 anatomic differences in children that change your mangement in a trauma
- Big head - need spine board cutout
- high risk of C1-3 injury
- higher risk of cervical/neuro injury
- anterior trachea - no cuff when intubate
- low blood volume - compensate and crash quickly
- high HR, low BP
- spleen and liver are not covered by ribs
- rib cage is more elastic
- less rib fractures, more thoracic injury
- higher body surface area - at risk of hypothermia
What it the tile classification?
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A - stable
- A1-fracture not involving the ring (avulsion or iliac wing fracture)
- A2-stable or minimally displaced fracture of the ring
-
B - rotationally unstable, vertically stable
- B1-open book
- B2-lateral compression, ipsilateral
- B3-lateral compression, contralateral (bucket-handle injury)
-
C - rotationally and vertically unstable
- C1-unilateral
- C2-bilateral
- C3-associated acetabular fracture
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What is the young-burgess classification?
-
Anterior Posterior Compression (APC)
-
APC I
- Symphysis diastasis < 2 cm
- Non-operative. Protected weight bearing
-
APC II
- Anterior SI joint diastasis
- Posterior SI ligaments remain intact.
- Anterior symphyseal plate or external fixator
-
APC III
- Disruption of anterior and posterior SI ligaments (SI dislocation).
- APCIII injuries associated with vascular injury
- Anterior symphyseal plate or external fixator and posterior stabilization with SI screws
-
APC I
-
Lateral Compression (LC)
-
LC Type I
- Oblique ramus fracture and ipsilateral anterior sacral ala compression fracture.
- Non-operative. Protected weight bearing
-
LC Type II
- Ramii fracture and ipsilateral posterior ilium fracture dislocation (Crescent fracture).
- Open reduction and internal fixation of ilium
-
LC Type III
- Ipsilateral lateral compression and contralateral APC (windswept pelvis).
- Common mechanism is rollover vehicle accident or pedestrian vs auto.
- Posterior stabilization with plate or SI screws as needed. Percutaneous or open based on injury pattern and surgeon preference.
-
LC Type I
-
Vertical Shear (VS)
- Posterior and superior directed force.
- Associated with the highest risk of hypovolemic shock (63%); mortality rate up to 25%
- Posterior stabilization with plate or SI screws as needed. Percutaneous or open based on injury pattern and surgeon preference.
How do pediatric pevlic fractures differ from adult fractures?
- if triradiate cartilage is open the iliac wing is weaker than the elastic pelvic ligaments, resulting in bone failure before pelvic ring disruption
- for this reason fractures usually involve the pubic rami and iliac wings and rarely require surgical treatment
Complications associated with pevlic fractures
- Dyspyruneia
- exctretory dysfuction
- sexual/erectile dysfunction
- decreased quality of life
- chronic pelvic pain
- **Neurologic injury **
- L5 nerve root runs over sacral ala joint
- may be injured if SI screw is placed to anterior
- **DVT and PE **
- DVT in ~ 60%, PE in ~ 27%
- prophylaxis essential
- mechanical compression
- pharmacologic prevention (LMWH or Lovenox)
- vena caval filters (closed head injury)
-
Chronic instability
- rare complication; can be seen in nonoperative cases
- presents with subjective instability and mechanical symptoms
- _diagnosed with alternating single-leg-stance pelvic radiographs _
What are the most common sites of compression of the ulnar nerve
arcade of Struthers
medial intermuscular septumm
edial epicondyle
cubital tunnel
deep flexor pronator aponeurosis
What are the zones of guyons canal
-
Zone 1
- Proximal to bifurcation of the nerve
- Ganglia and hook of hamate fractures
- Mixed motor and sensory
-
Zone 2
- Surrounds deep motor branch
- Ganglia and hook of hamate fractures
- Motor only
-
Zone 3
- Surrounds superficial sensory branch
- Ulnar artery thrombosis or aneurysm
- Sensory only
-
Zone 4
- compression of the motor branch with sparing of hypothenar
-
Zone 5
- compression of only index/middle interosseous with adductor
What are the boundaries of guyons canal
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Floor
- Transverse carpal ligament, hypothenar muscles
-
Roof
- Volar carpal ligament
-
Ulnar border
- Pisiform and pisohamate ligament, abductor digiti minimi muscle belly
-
Radial border
- Hook of hamate
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Common etiologies of ulnar tunnel syndrome
- gaglia are most common
- if making a list you can list any benign tumor of the hand or several carpal articulations
- vibratory compression is second most common
- or prolong pressure, as in cycling
- hook of hamate - most common traumatic finding
- can also list pisiform, MT base, DR, ulnar styloid
- arterial thrombosis/anerysm (hypothenar hammer syndrome)
- Anomalous muscle, fibrous bands
- OA/RA - synovitis, pannus, boney deformity
- DM, EtOH, renal failure, scleroderma
- Iatrogenic - CTR
Conditions that can present with ulnar neuropathy as their main complaint
peripheral neuropathy (cubital tunnel more common location of compression)
infectious/polio neuropathy
brachial plexopathy
malignant nerve sheath tumors
CMT
ALS
What tests help you distinguish elbow vs wrist ulnar nerve compression
-
palmaris brevis sign = excessive contraction of palmaris brevis with 5th digit abduction
- loss brevis with compression at guyons canal, but not cubital tunnel…need to clarify; potentially martin-gruber???
- PB is innervated by the superficial sensory branch of the ulnar nerve, so you will loose function with a zone 3 injury
- Sensation of dorsal 4/5 digits
- Tinels sign at elbow
- numbness with 1 min elbow flexion
Describe findings associated with zone 2 guyon canal compression
- decreased grip/pinch - 1st interosseous/adductor
- Froment sign - weak adductor
- Wartenberg sign - inability to aDduct the 5th digit (loss 3rd interosseous)
- Inability to cross index/middle finger - weak interosseous