Anatomy - hip and pelvis Flashcards
List four dangers of the Stoppa approach
Corona Mortis (lateral 1/3 sup. pubic ramus)Bladder (insert foley)Obturator nerve and vessels (when exposing quad plate)External iliac vessels (mobilize early)
What is the potential space of retzius ?
Anterior to bladder post to pubic symphisis
What muscle do you have to take down to see quadrilateral plate?
Rectus abdominus
What fascia separates the middle and lateral window of the ilioinguinal approach?
Iliopectineal fascia
List five contents of the Greater sciatic notch
piriformissuperior and inferior gluteal vessels and nervessciatic and posterior femoral cutaneous nervesinternal pudendal vesselsnerves to the obturator internus and quadratus femoris
List the structures that separate the windows in the ilioinguinal approach
Lateral: Iliac wing to Iliopsoas and femoral nerveMiddle: psoas to External iliac vesselsMedial: External iliac vesselst to rectus abdominus
What are the Denis zones of the sacrum?
1: lateral to foramen2: middle3: medial to foramina into spinal canal
What nerve root runs along the sacral ala?
L5
What is the sacral ala?
Top of sacrum forming iliosacral triangle
What is the importance of iliac cortical density?
On the lateral this parallels the alar slope, you want to be below this when inserting an SI screw
On an AP pelvis is the posterior wall lateral or anterior?
Lateral!
Judet views describe
Obturator oblique - AC (iliopectineal line), PWIliac oblique - AW, PC (ilioischial line)
What is a morale lavale lesion?
Internal degloving of subcutaneous tissue off of the lumbosacral fascia
What are key SI ligaments? What are the other three important ones?
Anterior, Posterior, InterosseousSacrotuberous, Sacrospinous, Iliolumbar ligament
Name the Contents of the Sciatic Notch Relative to Piriformis
Contents of GSNAbove piriformis:Superior Gluteal Nerve & ArteryBelow Piriformis:Pudendal nerve and internal pudendal arteryNerve to obturator internusPosterior femoral cutaneous nerveSciatic nerveInferior gluteal artery and nerveNerve to quadratus femoris
What travels through LSN?
Obturator internus muscleNerve to obturator internusPudendal nerveInternal pudendal vein
What is the cruciate anastomosis made of?
First perforator of profundaInferiorgluteal arteryMCFALCFAClinical Relevance:The cruciate anastomosis is clinically relevant because if there is a blockage between the femoral artery and external iliac artery, blood can reach the popliteal artery by means of the anastomosis. The route of blood is:Internal iliac –> inferior gluteal artery –> a perforating branch of the deep femoral artery –> lateral circumflex femoral artery –> its descending branch –> superior lateral genicular artery –> popliteal artery.
Nerves relative to psoas Lateral (3) Medial (2) Between iliac and psoas 1 Piercing than anterior
Lateral - iliohypogastric, lioinguinal, LFCNMedial - obturator, lumbosacral trunkBetween - femoralPiercing - genitofemoral
What nerve is at risk with a retractor under transverse acetabular ligament?
Obturator
How can we adduct after an obturator neurectomy
Pectineus, femoral
What nerve is above piriformis?
Superior gluteal nerve
What structure is most at risk of posterior ICBG harvest?
Superior gluteal artery, to a lesser extent cluneal nerves
Between What muscles does the posterior obturator nerve run between?
Adductor brevis and magnus
In the anterior Smith-Peterson approach the deep interval is between?
Rectus femoris and Gluteus medius
Name the ligaments connecting the pubic sympysis
Superior pubic ligament (stronger)Inferior (arcuate) public ligament
What type of joint is the pubic symphysis?
Synovial amphiarthroidal joint
What do the medial sacral crest and alae of the sacrum represent embryologically?
Medial sacral crest: fused spinous processesAlae and SI articular processes: fused TP and costal processes
What strucures are near the posterior sacral foramina?
Dorsal primary rami
What structures are near the anterior sacral foramina?
Ventral primary rami
In which direction are the coccyx of men and women directed?
Men: anteriorly towards pubis (like a penis)Women: vertically
List the signs of sacral dysmorphism
5 signs:Sacralization of L5Lumbarization of S1Mammillary processesOval or oblong foramenTongue in Groove sign of SI joint
What are the superficial surface markings of the SI joint?
Dimples of Venus
At what age are the SI joints fused by?
Age 50
Name the ligaments of the SI joint
PosteriorAnteriorInterosseous
WHere does the sacrotuberous ligament, sacrosinous ligament and iliolumbar ligaments run?
Sacrotuberous: sacrum to ischial tuberositySacrospinous: sacrum to ischial spineIliolumbar: iliac crest fo 5th lumbar TP
What are the boundaries of the greater sciatic notch?
PSISIschial spineNote: the sacrospinous ligament changes the “notch” into a “foramen”
What are the borders of the lesser sciatic foramen?
Ischial spine and tuberositysacrospinous ligament (superior border)sacrotuberous ligament (inferior border)
What the obturator foramen, membrane and canal?
Foramen: big hole between pubic ramiMembrane: Membrane that covers the foramen (obturator int/ext attach)Canal: superior opening in membrane, allowing passage of obturator n/a/v
What attaches to the obturator membrane?
Obturator internusand externus
What is the anteversion of the femoral neck?
15 degrees
What is the average neck shaft angle of the femur?
~127 degrees
What is the version of the acetabulum?
15 degrees anteverted (to match the femur)
What are the ligaments that make up the hip capusle?
Anterior:Iliofemoral ligament (Y ligament of Bigelow): Strongest ligament that runs from AIIS to intertrochanteric linePubofemoral ligamentPosterior:Ischiofemoral ligament: attaches to femoral neck
What is the zona orbicularis?
Circular fibers that form a collar around the femoral neckForm the annular ligament of the femoral neck
The labrum is continuous with what structure?
Transverse acetabular ligament
Describe the criteria for an adequate AP pelvis x-ray
Coccyx in line with symphysisSymmetric teardropssymmetric Obturator foraminaSymhysis:sacrococcygeal distance of:32mm in men47mm in women
What angle is classically measured off a Dunn view?
Alpha angleThe alpha angle is formed by a line drawn from the center of the femoral head through the center of the femoral neck, and a line from the center of the femoral head to the femoral head/neck junction, found by the point by which the femoral neck diverges from a circle drawn around the femoral head. At present, the upper end of normal is an alpha angle of 50 - 55 degrees.
What angle is measured from a false profile view?
Anterior CEA
List the 6 fundamental lines of Letournel
Anterior wallPosterior wallroof (or dome/tectum)iliopectineal line (anterior column)ilioischial line (posterior column)teardrop
List the levels of:Aortic bifurcationCommon iliac bifurcation
Aortic bifurcation: L4Common iliac bifurcation: S1
Name the branches of the internal iliac artery (6)
ObturatorSuperior and inferior glutealInternal pudendalVesicularLateral sacral
What is the corona mortis? Where is it located?
Common Anatomic variant (+ in 83%)Anatomosis between:Obturator + external iliac OR inferior epigastric arteries orLocated 40-96mm from the pubic symphysis (median 6cm)
What are the branhces of the profunda femoral artery?
Medial and lateral femoral circumflex arteriesPerforators
Descibe the course of the femoral artery in the thigh
Enters thigh from under inguinal ligament as the common femoral artery, a continuation of the external iliac arteryHere, it lies midway between the ASIS and the symphysis pubisThe common femoral artery gives off the profunda femoris artery and becomes the superficial femoral arterySuperficial descends along the anteromedial part of the thigh in the femoral triangleThen it enters and passes through the adductor (subsartorial) canalBecomes the popliteal artery as it passes through an opening in adductor magnus near the junction of the middle and distal thirds of the thigh
What is the primary blood supply to femoral head?
Medial femoral circumflex artery
Describe the proximal femur blood supply
MFCA: femoral head via retinacular vesselsLFCA: GTObturator: vessels within ligamentum teres
What are the borders of the femoral triangle?What makes up the floor, in what order?
Sartorius: laterallyAdductor longus: mediallyinguinal ligament: superiorlyFloor (lat to med): iliacus, psoas, pectineus, adductor longus
What are the contents of the femoral triangle?
NAVEL (spell NAVEL towards the navel, aka lateral to medial)
Describe the safe zone for acetabular screws:Which zone is safe? Dnagerous? What is at risk in each zone?
Divided into quadrants with one line running from ASIS to center of acetabulum and another line perpendicular to thatPosterior superior (Safest): sciatic nerve, superior gluteal n/a/vPosterior inferior: safe if screws Anterior superior: UNSAFE: external iliac artery/veinsAnterior inferior: UNSAFE: obturator n/a/v (b/c aiming for obturator foramen)
Name the short external rotators, from most proximal to most distal:
PiriformisGemellus superiorObturator internusGemellus inferiorObturator externusQuadratus femoris
Name the OINA of all the muscles of the hip - see list in answers
Good luck
Name the hip flexors and extensors:
Flexors:IliopsoasRectus femorisSartoriusExtensors:Gluteus maximusHamstrings: (ST, SM, BF)
Name the hip aB and aDDuctors
ABductors:gluteus mediusgluteus minimusTFL (in a flexed hip)Adductors:Adductor brevis, longus, magnusPectineusGracilis
What is the innervation of adductor magnus?
Dual:Obturator (adductor) posterior divisionTibial of sciatic (hamstrings)
Name the internal rotators of the hip
Gluteus medius (anterior fibers)Gluteus minimus (anterior fibers)TFLsemimembranosussemitendinosuspectineusadductor magnus (posterior fibers)
Describe the lubosacral plexus +/- draw it…..
Made up of lumbar and sacral plexi from T12 - S3Lumbar plexus: ventral rami of L1-L4 on anterior surface of quadratus lumborum within/deep to psoas majorSacral plexus: ventral rami from L4-S4
Name the origin and course of femoral nerve
Origin: L2-4Emerges between psoas and ilicusRuns superficial and medial to psoas tendonInto femoral triangledivides and innervates quads
What is the origin of LFCN and where does it exit pelvis?
L2-3Exits pelvis under inguinal ligament, 2cm distal to ASIS
Where is the sciatic nerve most likely to be found in relation to piriformis and SERs?
Deep to piriformis, superficial to SER- Usually sits on top of SER, that’s why during a posterior approach you can use them to protect it
What is the internervous plane of the anterior approach to the hip?
Femoral and superior gluteal nerveSuperficial: sartorius & TFLDeep: Rectus femoris and gluteus medius
In the lateral approach to the hip, where does the superior gluteal nerve run?
3-5cm above GT
What is the interval for the medial (Ludloff) approach to the hip?
Incision: 3cm below pubic tubercleNo real internervous planeSuperficial: adductor longus/gracilis: both anterior division of obturator nerveDeep: adductor brevis and adductor magnus: posteriorly by sciatic nerve, anterior adductor division by the posterior division of the obturator nerveDangers:Anterior division of obturator nerve between longus/brevisPosterior division of obturator nerve on magnus & under brevisMedial femoral circumflex artery on distal psoas
Name the dangers of the ilioinguinal approach
Nerves:Femoral nerve: running beneath inguinal canal on iliopsoasLFCN: medial to ASIS beneath external obliqueVessels:Femoral vessels: in femoral sheathInferior epigastric artery: medial to inginal ring. LigateCorona mortisOther:BladderSpermatic cord/round ligament
Where do the cluneal nerves run in a posterior bone graft approach?
8cm lateral to midline, so stay medial
Where do the superior gluteal vessels run in a posterior approach to bone graft?
Near the sciatic notchStay proximal to sciatic notch
What is the most common nerve injured during THA?
Sciatic, peroneal division b/c it is more lateral
What is the only muscle innervated by peroneal nerve proximal to the fibular neck?
Short head of biceps femoris
What is the most common complication in posterior iliac crest bone graft harvesting?
Injury to the superior gluteal artery
Which vessel provides the dominant supply to the femoral head?
Lateral epiphyseal vessels of the MCFA
A patient is undergoing percutaneous S1 SI screw fixation for a sacroiliac joint diastasis. What is the most common strength deficit sequela of this proposed screw trajectory? 1. Loss of hip flexion2. Loss of knee extension3. Loss of ankle dorsiflexion4. Loss of great toe extension5. Loss of ankle plantar flexion
4: Loss of great toe extension due to damage to L5
What is the only hip approah with a true internervous plane? What is the plane?
Anterior (Smith Peterson) approachFemoral & superior gluteal nervesSuperficial: Sartorius & TFLDeep: G. med & rectus femoris
What are the dangers of the anterior approach to the hip?
LFCN: 2.5cm below ASIS, passing over sartorius- Go through fascia of TFL (Hueter approach) to avoid damaging itFemoral artery and nerveAscending branch of LFCA
What are the planes and dangers of the lateral approach to the hip?
Plane: No true internervous plane:Muscle splitting: Gluteus medius (SGN) proximally and v.laterais (femoral) distallyDangers:SGN: 3-5cm proximal to GTFemoral bundle: gentle anterior retractor placementTransverse branch of the lateral femoral circumflex artery
What is the plane and dangers of the anterolateral approach to the hip?
Plane: No true internervous plane: SGNTFL/G. mediusDangers:femoral n/a/v overlying psoas: protect with careful anterior retraction
What is the plane/dangers of the posterior approch to the hip?
Plane: No true plane: ITB/glut maximus splitDangers:Sciatic nerve: reflect SER to protect it. Beware early division variantInferior gluteal artery: when splitting g.max, ligate/coagulate if seen. May retract into pelvis causing uncontrollable bleedingAscending branches of medial femoral circumflex artery. Protect by preserving quadratus femoris. Safe to release the proximal 1cm of quadratus femoris
What is the most common position of the sciatic nerve in relation to the piriformis? What are the other variants?
See picture
Describe the position, incision, plane and dangers of the surgical dislocation of the hip:
Position: LateralIncision: Lateral skin incision or one that is just anterior to the usual posterior approach incisionPlane: None: SGN onlyIncise TFL & ID g. mediusGT osteotomyElevate g. minimus and capsuleCapsulotomyDislocate anteriorly
Describe the medial approach to the hip:PositionIncisionPlaneDangers
Position: Supine with hip flexed, abducted and ER (figure 4)Incision: 3cm below pubic tubercle. Can be either mini transverse (for adductor release) or longitudinal down adductor longusPlane:Superficial: adductor longus/gracilis. Both anterior division of the obturator nerveDeep: Adductor brevis/Adductor magnus. Posteriorly by sciatic nerve. Anteriorly by posterior division of the obturator nerveDangers:Anterior division of obturator nerve: between longus and brevisPosterior division of obturator nerve: runs on adductor magnus and under brevisMedial femoral circumflex artery: runs medally on distal part of psoas tendon
What are the dangers in a posterior approach to PSIS for bone grafting? what is more commonly injured?
Superior gluteal a/v (more commonly injured)Cluneal nerves: 8cm lateral to midline at PSIS
What does the external iliac artery become?
Common femoral artery, after the inguinal ligament
