MCQs – Spine 2

MCQs-spine 2
contribute to hypoplasia of the dens. The proximal physis develops a secondary ossification center when the child is 8-10 years old – the ossicle terminale. Fusion of this to the rest of the dens occurs at age 10-13.

– note: the neurocentral synchondrosis DOES NOT contribute significantly to the vertical growth of the dens. It comes from the other end (the tip).

– C-spine injuries in young children 10 (whether symptomatic or not) or if they have any instability with neurologic signs and or symptoms (neck pain, stiff neck, torticollis, progressive weakness, decreasing endurance, loss of bowel or bladder control, clumsiness, change in gait pattern.)

Approach To Inflammatory Arthritis – Hip Arthritis

Approach to Inflammatory Arthritis – Hip Arthritis

– rheumatoids get concentric wear with erosive changes, and end up with protrusio which tends to be progressive
– bone turnover has been shown to be higher in the peri-articular area – be wary of trying non-cemented techniques, because you may not be able to depend on bone ingrowth.
– in general, rheumatoids have shown increased rates of loosening of the femoral and acetabular components
– they also have increased risk of infection

– there is NO ROLE FOR OSTEOTOMY in this patient population
– technically, be wary of the protrusio – may have to do in-situ osteotomy of the femoral neck; be careful about dislocating the bone – it is very soft and is at risk of fracture; be careful about doing trochanteric osteotomies or slides – the bony healing is not optimal in the rheumatoids and you may precipitate a nonunion.
– the gold standard is cemented fixation, just because their bone is kinda hard to depend on for bony ingrowth
– DO NOT ATTEMPT INTERNAL FIXATION OF RHEUMATOID FEMORAL NECK FRACTURES UNLESS COMPLETELY UNDISPLACED – they DO NOT heal reliably and are better served with THA.

– beware high incidence of HO in ank sponds – be prepared for XRT or NSAIDS postop
– be wary of infection postop – these patients should all get prophylactic antibiotics before dental work, colonoscopy, or other procedures that may involve transient bacteremia
– Kephlex – 500 mg 1 hour preop, then 1 hour postop
– clindamycin if PCN allergic

Medial Unicompartmental Gonarthrosis

Medial Unicompartmental Gonarthrosis

Conservative Options

– NSAIDS – activity modification – viscosupplementation
– analgesia with Tylenol – physiotherapy – functional knee bracing
– oral glucosamine sulfate – weight loss – local measures (heat/ice)
– cane

Surgical Options

– arthroscopic debridement
– high tibial osteotomy
– unicompartmental arthroplasty
– total knee arthroplasty

Spinal Stenosis 2

Spinal stenosis2
8. Documented instability at the level on flex/ext views – >4mm translation, > 10 degrees of angulation.
Intraoperative Structural Alterations
– taking >50% of the facet – the motion segment is unstable and should be fused.
– taking the disc out – aggressive discectomy renders the anterior column unstable and should be fused

The addition of instrumentation – also a controversial thing!

– Consider adding instrumentation when: 1. Correcting deformity. 2. Fusing more than one motion segment. 3. Treating recurrent stenosis and iatrogenic spondylolisthesis. 4. Documented instability preoperatively.
– the addition of pedicle screws to a single level degenerative spondy has been shown (Fishgrund) to improve fusion rates, but this had no effect on patient outcome.

MCQs – Upper Extremity/Elbow 3

MCQs-UE/elbow 3
Mason III fracture that is clearly un-reconstructable. In a Mason II fracture that you cannot fix, well, you might as well take that out too, as long as the rest of the elbow were stable and a longitudinal injury did not exists. Do not do partial excisions.

– for patients who come back long-term after having a radial head fracture that has not done very well, late excision has been reported to decrease pain and increase function in 70-80% of cases.

– for ununited lateral condyle fracture – watch out for progressive cubitus valgus and tardy ulnar nerve symptoms

– indications for fixing a medial epicondyle fracture: significant displacement (8-10 mm), valgus instability, ulnar nerve symptoms, incarceration into the joint. Remember to transpose the nerve.

– the best way to prevent proximal migration after Essex Lopresti injury is to fix the radial head. There are no other good solutions. The IO membrane and ligament DOES NOT HEAL.

Non Ossifying Fibroma (NOF)

NOF
Nonossifiying Fibroma (NOF)

– metaphyseal fibrous lesion of long bones (esp around knee) in children
– advanced form of fibrous cortical defect because no longer confined to cortex but extend into medullary canal
– usu ossify by 3rd decade

Signs & Symptoms:
– painful lesion
– pathological #

Xrays:
– clearly demarcated, eccentric, multilocular expansile lesions with scalloped, sclerotic margins
– bilateral or multiple lesions common
– cortex may be attenuated in areas adjacent to lesion

Histology:
– spindle cells arranged in storiform pattern
– whorls of connective tissue interspersed with multinucleated giant cells & lipid-laden macrophages (foam cells)

Treatment:
– self-limited lesions – observation
– large lesions that encompass > 50% bone diameter may require curettage & bone grafting (impending pathologic #)

Calcaneal 1

Calcaneal 1
Calcaneal Fractures

Reference: Heckmann, James, in Rockwood and Green, 1996, Chapter 32

Main Message

These are devastating injuries. The jury is out with regards to the treatment. Probably, there are some that are better fixed, particularly by those who are good at them, and some that are better left alone. One hopes that Buckley’s study will delineate some of that…

Points of Interest

Anatomy

Plantar Surface – medial and lateral processes – for attachment of the plantar fascia and intrinsic foot muscles.
Dorsal Surface – posterior, middle, anterior facets
– Posterior facet – convex; makes up most of the subtalar joint
– Middle facet – concave; situated on the sustentaculum tali
– Anterior facet – concave; confluent with the middle facet
The calcaneal groove and interosseous ligament lies between the middle and posterior facets.

Bohler’s angle: the complement of the angle formed by a line drawn from the highest point of the anterior process to the highest part of the posterior process, and a line drawn from this point to the highest part of the tuberosity.

Most fractures are intra-articular – caused by axial loading. But there are many that are caused by twisting injuries – these are usually extra-articular.

Radiographs

– AP and lateral views are good
– Axial view of the calcaneus shows the width
– Broden’s view (a medial oblique view) – internally rotate the foot 45o, then shoot at 40, 30, 20, 10 degrees cephalad to get the right AP projection of the posterior facet
– Lateral oblique view – externally rotate the foot 60o and shoot 10o cephalad to get a good lateral of the posterior facet.

Extra-Articular Fractures

Anterior Process
Tuberosity
Medial Process
Sustentaculum Tali
Body

Anterior Process
– either avulsion fracture of the anterior process by the “bifurcate ligament” – a ligament the connects the anterior process to the navicular and cuneiform; or a compression fracture (more unusual)
– the pain is noted anterior and inferior to the anterior talofibular ligament, which makes it distinguishable from ankle sprains
– usually treated with cast immobilization; if large and unreduced, you can fix them. If they don’t heal, they may not be symptomatic. If they are, you can excise them with good results.

Tuberosity
– avulsion of the Achilles tendon
– if minimally displaced, cast in slight equinus, 6 weeks
– if displaced, ORIF with tension band or screw, then cast in slight equinus

Medial Process
– serves as the origin of the abductor hallucis and the medial portion of FDB and plantar fascia
– avulsion of the plantar fascia
– treat with walking cast with molding to push the medial process laterally.

Sustentaculum Tali
– a Sanders IIC fracture
– pain is often accentuated by passively extending the great toe (pulls up on FHL)
– axial x-rays and CT are critical
– cast if nondisplaced. If more than 2 mm displaced, need to fix.

Body Fractures
– these spare the subtalar joint
– Bohler’s angle may be decreased, but with congruity of the subtalar joint
– generally speaking, require no treatment at all
– the indications to treat these are 1. If Bohler’s angle is significantly reduced (by 10o or more) because of the loss of mechanical advantage of the tendo-achilles. 2. If the heel has been significantly widened (will lead to difficult shoe wear and ulceration)
– If Bohler’s angle is reduced, you can put a Steinman pin transversely through the tuberosity, pull down on it, then put them into a cast, incorporating the pin.

Intra-Articular Fractures

Primary Fracture Line – runs obliquely from plantarmedial to dorsolateral, creating an anteromedial (sustentacular) fragment and a posterolateral (tuberosity) fragment. The sustentacular fragment is rarely comminuted, being attached to the talus by the strong deltoid and interosseous talocalcaneal ligaments. The tuberosity fragment is the one that gets shmucked.
– This primary fracture line is created in this fashion because the talus sits

Acetabulum – Ilioinguinal Approach

Acetabulum – ilioinguinal approach

• position – supine with GT @ edge of table
– need catheter

• incision – curved ant. Incision starting 5cm above ASIS
– 1cm above pubic tubercle to midline

* no internervous plane

* dissection
– incise subcut. fat
– expose aponeuroses of ext. oblique
– lat. fem. cut. n. in lat. edge of dissection
– divide ext. oblique from superficial inguinal ring to ASIS
– ID round lig. or spermatic cord = med. bundle
– divide ant. part of rectus sheath to expose underlying rectus
– strip iliacus from inside of wing of ilium –> can expose SI joint
– divide rectus transversely 1cm prox. to insertion
– develop plane btw back of symphysis & bladder = space of Retzius)
– peel fibers of int. oblique & transversus from inguinal lig. –> avoids inf. epigastric art. & deep inguinal ring
– push peritoneum upwards to expose ext. iliac vessels
– isolate ext. iliac vessels = middle bundle
– isolate iliopsoas & fem. n. = lat. bundle
– expose med. surface of acetabulum & sup. pubic ramus

* dangers
– fem. n. – runs beneath inguinal lig. lying on iliopsoas; avoid excessive retraction

– inf. epigastric art. – passes med. to deep inguinal lig.

– spermatic cord – contains vas deferens & testicular art.

– bladder – easily mobilized off back of symphsis

– corona mortis
> anastomosis of branch of obturator art. & ext. iliac art.
> occurs in 25-30% of patients
> on undersurface of ext. iliac art.

Tibia – Posterolateral Approach

Tibia – posterolateral approach

* used to expose middle 2/3 of tibia when skin over subcut. surface is badly scarred or infected

* position – 45deg. of lat. decubitus position with affected leg up with tourniquet

* internervous plane – gastroc/soleus/FHL (tibial n.) & peroneal muscles (SPN)

* dissection
– reflect skin flaps taking care with lesser saphenous vein
– incise fascia in line with incision
– find plane btw lat. head of gastroc/soleus post. & PB/PL ant.
– muscular branches of peroneal art. lie with PB in prox. part of incision
– find lat. border of soleus & retract med. & post.
– ID FHL below arising from post. surface of fibula
– detach lower part of origin of soleus from fibula & retract med. & post.
– detach FHL from origin on fibula
– dissect med. across interosseous membrane detaching fibers of TP that arise from it
– follow interosseous membrane to lat. border of tibia
– expose post. surface of tibia subperiosteally

* dangers
– lesser saphenous vein – may be damage when skin flaps are mobilized
– peroneal art. – branches cross btw gastroc & PB muscles
– PTA & tibial n. – lay post. to FHL & TP

Retrograde Femoral Nails

Retrograde Femoral Nails

Indications (Ross Leighton)
Absolute
1. Floating knee
2. Bilateral Femur #’s
Relative
1. Obesity
2. Pregnancy
3. Ipsilateral femoral neck and shaft
4. Ipsilateral complex acetabulum (ie. Won’t interfere with incisions)
5. Ipsilateral patella or knee ligament
6. Ipsilateral TKR with peri-prosthetic supracondylar #