Subtalar Joint Arthrodesis (STJ) – a McGlamry review

STJ FUSION (SUBTALAR JOINT ARTHRODESIS) CHEAT SHEET

1. How are the major tarsal joints affected with a fusion? : TN fusion limits STJ motion the most (8%). STJ fusion still allows 25% TN and 55t% CC motion (astion). -the take home is that an isolated STJ fusion (vs triple) preserves 50% of mid tarsal joint motion.

2. Do TAL before fusion? YES

3. What type of Incision: inferior posterior tip of fibula to CC joint OLLIER approach (sinus tarsi approach) – advantageous because it can be curved along langer’s lines for good healing:

 a. What should you be careful to protect during the incisionincision is superior to the 1. peroneals and 2. sural nerve and inferior to 1. intermedial dorsal cutaneous nerve so be careful!  ****communicating branch from sural nerve to the intermedial dorsal cutaneous nerve may exist and therefore needs to be completely transected to avoid any neuritis!

b. What ligaments are usually transected? sinus tarsi is cleaned out, interosseus talocalcaneal ligament is transected, lateral TC and CF ligaments incised. crego elevator is positioned at the lateral aspect of talocalcaneal joint and directed posterior -> exposes posterior subtalar joint

4. Should all facets of the STJ fusion be performed? No. Fusion of middle facet is not necessary (FHL injury)

5. What are some techniques to prepare the joint to encourage bleeding? Subchondral k-wire drilling VS “Fish scaling” – using a small osteotome to the subchondral bone to ensure exposure of cancellous substrate and increase surface for fusion across joint vs simple curettage – least effective according to podiatrytoday.com articles

6. What are two techniques to prepare the joint via cartilage removal? Wedge resection (adding bone to the fusion site in severe deformities ) vs contour resection (most common – it maintains natural joint contours)

7. What is the most important step in STJ ARTHRODESIS AS PER McGlamry: proper reduction and positioning. TWO-hand technique: :first hand: “heel is grasped with the palm of one hand, while the thumb of the same hand is placed on the talar head, next an inversion force with the palm on the heel and a medial to lateral pressure with the thumb over the talar head is applied -> this allows the heel to be in neutral position (5-7degrees of valgus and 10 degrees of external rotation) this lines up the mechanical axis for proper weightbearing -> the TN joint is reduced. second hand: grasp the forefoot and any residual forefoot varus is reduced or “dialed down” to ensure plantigrade foot.   

  • in summary – 1. rotate the heel into a neutral position while pushing against the talar head to reduce the talonavicular joint 2. reduce any forefoot supinatus simultaneously 3. drill k-wire to fixate this position

8. **What to look for on fluoro**? lateral: normal cyma line, unmasking of cuboid, good apposition of STJ. AP: adequate talar head coverage without a tendency toward excessive forefoot abduction. calc axial: IMPORTANT VIEW THAT MANY SURGEONS FAIL TO DO: look for neutral alignment  of the heel in relation to bisection of tibia .

b. what position do you want the heel on a calcaneal axial to be fused? slight valgus position of the calcaneus in relation to the tibia

9. What is the non union rate for STJ fusion? 10%

10. What factors usually complicate STJ fusions? – patient usually has poor bone stock, scar tissue/fibrosis can limit reduction of STJ and since it is avascular can cause wound problems

11. most common complication of arthrodesis? non-union or fibrous union(pseudoarthrosis)

 

Podiatry Interview Practice

How do you fixate a danis weber B ?

Danis weber B with a medial mall fracture classifies which SER? SER 4

AP/ Mortise decreased overlap = syndesmotic rupture

How to fix syndesmosis? 3 screws, tight rope, 4 screws

How do position the tight rope for syndesmosis?

Pic of erythrysma? medication? erythrymcin

Topical ointment for MRSA ? pic of infection – Bactroban

Oral medication for mrsa? Bactrim

What is the dose for Lamisil? 250mg

Should you plate a high fibular fracture? No, be aware of common peroneal

Posterior spike synonymous with? SER2

Secondary ORIF using a delta frame for comminuted pilon fracture. Why? wound dehiscnence wait for swelling, and ligamentotaxis

Name some nsaids other than Ibuprofen

What should you always order for pilon fxs? CT

How do you evaluate the posterior facet from a lateral view for intra-operative Calc fxs? Broden’s view

What is AO principles?

Pic of well defined lesions in caclaneus. Name 3 differentials – UBC, ABC, Lipoma, GCT

Pic of well defined lesions in fingers. Name 3 differentials – GCT, enchondromas

Flat foot reconstruction pics – name the procedures, name the plane of dominance

What are P’s of compartment syndrome?

Which side of the talus is this?

What should be used for CRPS?

What is Sudeck’s atrophy?

Name the stages of charcot and how each stage is treated?

Name 3 lateral ankle stablization procedures?

Pic of christmas snook xray with a hole in the fibula. What procedures and where does it attach? Christman snook

Clicking sound heard upon ROM ankle, pain along lateral side of ankle, constant sprains. what Musculoskeletal questions? eversion prodceues pain, palpate the peroneal tendon, have patient do a talar tilt.  know all eckert and davis classifications and who added the last classification?  Oden

What foot type causes Haglunds? compensated forefoot valgus, compensated forefoot varus, rearfoot varus

 

 

 

100’s of Podiatric EPONYMS

Can be cateogrized by “physical examination – and subcategorized – patient does the test? eg jack’s test….or physician squeezes something and causes tinel’s sign”

 

Silver

Keller

Mitchell

Chevron

Austin

Joplin

Youngswick

Hohmann

Riverdin

Riverdin – Green

Mc Bride

Logroscino

Hibb’s angle/tenosus

Young’s

Fowler

Cotton 

Lapidus

Evan’s

Hoke’s fusion

Hoke’s recession

Hoke’s tonsil

Charcot foot

Morton’s neuroma

Jone’s fracture

Stieda’s process

Cedell’s fracture

Sheperd’s fracutre

Heberden’s nodes

Bouchard’s nodes

Hubscheur maneuveur

Jack’s test

Tinel’s sign

Valeux’s sign

Kirby’s sign

Engle’s angle

Simon’s angle

Kite’s angle

Lachman’s test

McMurray’s test

Coonrad-Bugg-Trap

Renandier’ s disease – tibial sesamoid

Trevor’ s disease – fibular sesamoid

Freiberg’ s disease – second metatarsal head

 

Kohler’ s disease – navicular

 

Diaz/Mouchet disease – talus

 

Blount’s disease in adolescents – medial proximal tibial epiphysis

 

Legg Calve Perthes Disease – femoral head

Sever’s disease – calcaneus

Theimann’s disease – phalanges (hand and foot)

Islen’ s disease – 5th MT base

Haglund’ s disease – accessory navicular

Osgood Schlatter’s disease – tibial tuberosity

Blount’s disease in children – proximal medial tibial epiphysis

Reiter’s syndrome

 

 

 

APMLE Exam II – CSPE

 

Which are the most common treatments used?

  • Cam Walker
  • NSAIDS
  • RICE
  • Custom orthotics
  • Compression stockings

 

Plantar Fasciitis

CC: Pain is worse upon ambulation at mornings. Pain is on the medial posterior heel. Patient had pain for a couple years.

Objective: MSK- POP to medial calcaneal tubercle. Equinus.

Assessment: Plantar fasciitis

Plan: Duexis (NSAID), Stretching, RICE,

Hammertoes/Bunion

Gas gangrene

Plantar wart

Tinea pedis/ungium

Gout

Hallux limitus/arthiritis

DFU (Neuropathic)

VLU

Ischemic leg ulcer

Ruptured achilles tendon

Capsulitis

Midfoot arthritis

Toe fracture/Metatarsal fx

Ankle fracture/Calcaneal fracture

Peroneal tendinitis

PTTD

Talar dome lesion

Plantar Neuroma

Tarsal tunnel syndrome

Cellulitis

 

Podiatry Made Easy – A compilation of mnemonics and memory aids

Podiatry Mnemonics

CONGENITAL DEFECTS

Brachymetatarsia

“Bra” in the name can give you two clues. The B in bra means it is usually bi-lateral and affects females. There are 4 A’s in the name, so it most commonly affects the 4th toe.

 

Polydactyly

Polydactyly refers to an extra digit. There are two classifications for post-axial and pre-axial. Both classifications have “poly names” i.e. two names in each classification. The pre-axial classification is called Temtamy & McKusick. Note how temtamy sounds like tem-temy, which is similar to an extra digit! It is doubled.  The post axial classification is called Venn Watson. Note how the V is like the pattern in post axial polydactly, which resembles a V.  Another association with the V is that there are 5 types under the Venn Watson classifcation, from A – E. There is an E in complete, for complete duplication. So D, is partial duplication.

 

Ectrodactyly

This is also known as lobster extremities.  The classification is Blauth and Borish, which you can picture as two lobsters, Blau and Bor. The first letter, is B&B (bed and breakfast), which starts at 6am. There are 6 classifications. If you can remember the classification system is based on loss of digits, then the last classification, i.e the 6th one, is for one met. You must have at least one met or else there won’t be anything to classify!

 

FIbular

Achterman and Kalamachi  classification: There are two words. It comprises of 1 and 2, in which type 1 there is a fibula and type 2 there isn’t. Type 1 can be subdivided into A and B. The name of the classification is A-K (at knee which suggests its a bone at the knee and also addresses the growth plates!) The proximal growth plate of the fibula is inferior to the tibial growth plate, and the distal growth plate is just above the ankle. The fibula looks displaced inferiorly. Whilst, type 1B represents a shortened fibula, i.e the proximal fibula is absent for part of it’s length. Therefore, type 1a fibula is normal length but looks displaced inferiorly, 1b the fibula is shortened, and type 2, there is no fibula.

Stanitski and Stanitski –

 

 

MRI imaging Made Easy – How to identify STIR imaging.

An introduction to identifying STIR images.

by Rossi Bad

Original Date: 2016-04

 

MRI image appearance

The best way to identify STIR images is to look for areas that should be filled with either fat or fluid. For example bone marrow should be filled with fat, and joint spaces should be filled with fluid. Next, you want to see that the fat is very dark, while the fluid is lighting up, and bright. Remember that STIR is a “fat suppression” technique that allows for detection of water and fluid content. 

Therefore, muscle will appear darker than fat. Bone marrow, blood, fat (eg. subcutaneous), air will also appear dark. Fluids will appear very bright. Since pathological processes usually involve edema, which is an increase in the water content, this type of MRI is great for for pathological processes.

With regards to the podiatry, a minimal amount of fluid is found within tendon sheaths. This is usually clinically insignificant. However, fluid within the flexor hallucis longus tendon is a common finding, and should not be treated as pathological. This is due to the communication between the sheath of the FHL and ankle joint.

 Therefore STIR is great for joint pathology, and tendon pathology.

stir images of a normal ankle
STIR – Ankle Sagittal MRI – note the BRIGHT fluid in the joints, and DARK bone marrow
STIR ankle joint normal
STIR – sagittal MRI ankle. Remember: look at the joints: BRIGHT. Look at the marrow: DARK.
ruptured tendoachilles STIR edema
Arrows show edema, ruptured tendoachilles tendon.

 

The following website is a great resource for identifying and learning about imaging techinques!

References:

https://mrimaster.com/index-2.html

 

ALL IMAGE CREDITS GO TO THE ORIGINAL CONTENT and AUTHORS LINKED IN THE IMAGE. I DID NOT REMOVE THE HYPERLINK.

A podiatric introduction to Biomechanics of the Foot

There are three main theories that help determine the cause of the foot pathology from a biomechanical standpoint:

  1. Sagittal plane facilitation (SPF)
  2. Subtalar joint neutral (SJN) or Foot Morphology theory
  3. Tissue stress theory (TS)

 

STJN was initially described by Merton L. Root, and therefore is  also known as “Rootian” biomechanics. STJN occurs at heel strike, and at the end of midstance. Foot morphology is currently used term to describe abnormal or normal foot function as it relates to STJN. For example, a foot that has FM that deviates from “normal” such as forefoot varus, would need to an orthotic device to return the foot to normal. If the foot remains with a forefoot varus,  pronatory compensatory motion would occur at the STJ thereby causing an abnormal STJN.

How is the orthosis made to return the abnormal FM to normal?

Negative Casting

  1. Casting the foot in NWB neutral position
  2. Lock the midfoot i.e. end point so that arch isn’t “wobbly”
  3. Ensure the forefoot to rearfoot alignment is correctly captured
  4. Ensure the cast has a proper arch, and the lateral edge of the foot is captured

Positive Cast

  1. After pouring

Podiatric Eponyms and Nicknames

Runner’s toe – subungal hematoma of the SECOND TOE

Tennis toe – subungal hematoma of HALLUX

Turf toe – sprain of HALLUX MPJ due to hyperextension

Sand toe – sprain of HALLUX MPJ due to hyperflexion

Runner’s knee – Patellofemoral dyfunction

Basketball foot – STJ dislocation

Lachman’s test – ACL test

McMurray’s test – Meniscal test

dreaded black line – transverse stress fracture across the anterior tibial cortex

Theater sign – patellofemoral dysfunction