Lower Limb and Pelvis Flashcards
What factors decide whether a total hip replacement should be done
pain and disability persisting after conservative interventions
ask about - analgesia, slee disturbance, rest pain, ADLs, walking distance, impact on job or hobbies
conservative interventions for OA of the hip are
weight loss
physio
walking aid
analgesia
early complications or THR
infection
dislocation
nerve injury - sciatic
leg length discrepency
general - MI, PE, hypovolemia, Mi etc.
late complications of THR
early loosening
late infection
late dislocation
causes of avascular necrosis of the hip
idiopathic
secondary to alcohol, steroids, hyperlipidaemia or thrombophilia
sign of AVN on x ray
‘hanging rope sign’ due to lytic zone under femoral head
management of AVN
if detected pre collapse - drill holes into femoral neck and head to relieve pressure
if collapsed - THR
typical presentation of trochanteric burstitis
pain and tenderness in the regoin of greater trochanter and pain on ressited abduction
which part of the body has the thickest hyaline cartelage
patella
role of the menisci in the knee
shock absorbers
the four ligaments of the knee are
ACL - prevents internal rotation of tibia
PCL - prevents hyperextension
MCL - resists valgus force
LCL - resits varus force
what prediscopses to easrly OA in the knee
meniscal tears
ligament injuries
genu varum (medial)
genu valgum (lateral)
risks after TKR
higher risk of unexplained pain
less risk of dislocation
other risks are similar to that of hip replacement
when do meniscal injuries classically occur
twisting force on a loaded knee eg during football
typical signs of a meniscal tear are
pain localised to either medial (most) or lateral joint line
effusion
pain and catching sensation
difficulty fully straightening the knee
knee may feel as though it is about to give way (sign of a loose fragment)
positive steinmann’s test
what is true knee locking
mechanical block to full extension caused by significantly torn meniscus flipping over and getting stuck in the joint line
what is pseudolocking
in other pathology eg arthritis the knee may feel as though it becomes stuck temporarily but is recovarable
how is an ACL injury typically sustained
turning the upper body laterally on a planted foot - higher rotational force
usually skiing, rugby, footbal
features of an ACL injury
pop usually felt or heard
haemarthrosis within an hour
deep knee pain
may complain in rotatory instability more chronically
positive lachman’s test and anterior drawer test
mechanism of MCL tear
usually valgus stress e.g. tackle from side in rugby
mechanism of LCL tear
varus stress
mechanism of PCL rupture
high force direct blow to anterior tibia with knee flexed
eg.RTA
investigation of choice in meniscal tear
MRI
most common side of meniscal tear
medial 10 x more common
what is a bucket handle meniscal tear
large meniscal fragment is able to flip out of its normal position and displace anteriorly or into the intercondylar notch where the knee locks and is unable to fully extend due to mechanical obstruction from the trapped meniscal fragment.
how can you differentiate between a degenerate meniscal tear and an acute traumatic tear
degenerate tears typically occur in older people
steinmann’s negative
associate with early signs and symptoms of OA
treatment of meniscal tears
repair - only in fresh longitudinal tears in outer 1/3 in young patients
most not suitable for replair - settle with time, steroid injections if degenerate, arthroscopic partial meniscetomy if not improved by 3 months
degenerate tears generally do not get surgery
prognosis of ACL tear
1/3 no problems
1/3 manage by avoiding certian activities and sports
1/3 poor with giving away during ADLs
treatment of ACL rupture
physio
can have repair but usually not effective
reconsturction with tendon graft
where is the graft usually taken from for an ACL reconstruction
patellar tendon
semitendinosis and gracilis autograft
management of MCL tear
most do well
acute tears treated with hinged knee brace
chronic instability - tightening of MCL or reconstruction with tendon graft
complications of complete knee dislocation
usually rupture all four knee tendons
risk of neurovascular injury
thrombosis and impaired circulation to lower limb
compartment syndrome
need vascular surgery input
factors which predispose to tendon rupture
tendontitis chronic steroid use diabetes rheumatoid arthritis chronic renal failure quinolones
patellar tendon ruptures tend to occur in what age group
young people under 40
quadriceps tendon ruptures tend to occur in what age group
older people over 40
chondromalacia patellae is
softening of the hyaline cartilage
what typically cause patellofemoral dysfucntion/anterior knee pain
excessive lateral pull on the patella
more common in adolescent females due to wider hips
in what direction does the patella usually dislocate
laterally
what ligament tears in patella dislocation
patella femoral
what occurs in the joint in patellar dislocation
lipo-haemarthrosis which has a characteristic x ray appearance
predisposing factors to patella dislocation
ligamentous laxity female genu valgum femoral neck anteversion high riding patella (patella alta)
treatment options for ankle OA
after conservative
arthrodesis - young patines
ankle replacement - better range of motion but more likley to loosen earlier and leave a shortened limb once failure is corrected
what are the ottowa rules for ankle injury
this determins whether or not to get an xray
need pain in malleolus zone plus one of the following:
bony tenderness at the lateral malleolar zone
bony tenderness at the medial malleolar zone
inability to walk four weight bearing steps immediately after the injury and in the emergency department
what is charcots foot
a joint which has become badly disrupted and damaged secondary to a loss of sensation
common in diabetics
what is hallux rigidus
OA of the first MTPJ
gold standard surgical treatment of hallux rigidus
arthrodesis
what is morton’s neuroma
irritated pplanter intergdigital nerves become inflamed and swollen forming a ‘neuroma’
typical symptoms of mortons neuroma
pain and burning in ball of the foot
examination finding in mortons neurmoma
mulder’s click test
squeexin metatarsal head result sin a click or reproduces symptoms
diagnosis of mortons neuroma
ultrasound
management or mortons neuroma
conservative - insole, sterois injections
surgical excision
management of metatarsal stress fracture
prolonged rest for 6-12 weeks in a rigid soled boot
who typically gets stress factures
runner’s
dancers
soldiers on long marches
what is never a treatment of achilles tendonitis
steroid injection - will predispose to rupture!
clinical test used to confrim achilles tendon rupture
simmonds test
squeezing calf muscle will not produced plantar flexion
management of achilles tendon rupture
surgical repair
non operative management in a series of casts with ankle plantar flexed for 8 weeks - usually has good outcome
typical history of plantar fasciitis and risk factors
pain in instep of foot
tenderness on palpation
diabetes obestity and lots of walking can predispose
causes of pes cavus
abnormally high arched foot
can be idiopathic but often related to neuromuscular conditons e.g. cerebral palsy, spina bifida
Marfan’s
what is claw toe
hhyperextension at MTPJ and hyperfelxtion ar PIP and DIP
what is hammer toe
Hammer toes are similar to claw toe but have hyperextension at the DIPJ.
what causes claw and hammer toe
acquired imbalance between the flexor and extensor tendons in feet
management of claw and hammer toe
Toe “sleeves” and corn plasters can prevent skin problems. Surgical solutions include tenotomy (division of an overactive tendon), tendon transfer, arthrodesis (PIPJ) or toe amputation.
