Foot and ankle Flashcards
What defines exertional compartment syndrome?
1 - Resting compartment pressure <15 mm Hg*
2 - 1 minute post exercise >/= 30 mm Hg*
3 - 5 minute pressure >/= 20 mm Hg***
How do patients present with popliteal artery entrapment syndrome?
Intermittent claudication and decreased pulses***
May present with pain, coolness and tingling in LE which is exacerbated with walking but better w/ running with normal compartment pressures***
Due to compressive effect of the medial gastroc on the popliteal artery***
Silfverskiold test?
Improved ankle dorsiflexion with knee flexed = gastrocnemius tightness***
Equivalent ankle dorsiflexion w/ knee flexion and extension = achilles tightness
Antagonist of posterior tibias?
Peroneus brevis** (PT/PB)
Why does plantar flexion of the first ray occur in cavovarus foot?
Due to weakness of anterior tibialis and overruling of peroneus longus***
How to test ATFL?
Anterior drawer in 20 deg of plantar flexion***
Shift >8 mm = incompetent ATFL
What is spring ligament?
Calcaneonavicular ligament
Static stabilizer of medial longitudinal arch
From sustentaculum tali to inferior aspect of navicular**
Spring ligament likely attenuated in type II flatfoot deformity 2/2 posterior tibial tendon dysfunction***
How do transverse tarsal joints lock to allow toe off during gait?
Subtalar joint INVERTS –> locks transverse tarsal joints to allow hindfoot/midfoot to be stable for toe off
Eversion = unlocks transverse tarsal joints to allow supple foot to accommodate ground just after heel strike
What is ass’d with os trigonum?
Where is os in relation to FHL, tibial nerve, artery etc?
FHL tenosynovitis or entrapment***
Can give posterolateral ankle pain with passive ankle plantarflexion*** (vs FHL pain which is posteromedial)
Os lies LATERAL to structures**
What does tibialis anterior do during heel strike?
Eccentrically contracts***
quad also eccentrically contracts during this phase***
Which gait phase will be affected most by patient with quad atrophy?
Hamstring or hip flexor weakness?
MIDSTANCE***
During stance phase of gait quad contracts to prevent buckling of knee**
In contrast –> weakness of hamstring or hip flexors are most affected during the SWING phase
What % of gait is in stance phase?
60%**
Tx of base of 5th metatarsal fx?
Type I: nonop with WBAT in boot
Type II: athlete = ORIF
non athlete/rec athlete = NWB in cast***
Type III = NWB in cast***
Where does Lisfranc ligament go?
Interosseous ligament that goes from base of 2nd metatarsal to medial cuneiform on PLANTAR side***
ORIF vs arthrodesis for ligamentous Lisfranc injury?
Arthrodesis = improved functional outcomes*
Increased return to activity*
Decreased rates of secondary surgery (only one that is consistently found in studies though)
Most common metatarsal fx in kids <4 y/o?
1st metatarsal***
Once greater than 5 y/o,, 5th metatarsal is most common**
Who gets navicular fx?
Common complication?
Tx?
Running athletes running on hard surface* –> usually chronic overuse injury*
At high risk of AVN**
Most common complication = DELAYED UNION and NONUNION***
Tx stress fx:
Cast immobilization, NWB (6-8 weeks)
Operative: high level atheletes
Nonop failure/nonunion
Tx traumatic fx:
NWB cast –> acute avulsion fx, tuberosity fx, non/minimally displaced fx
Operative for fx:
Fragment excision –> avulsion that doesn’t heal with nonop
ORIF: avulsion w/ >25% articular
Displaced fx
ORIF followed by ex fix vs fusion
AVN –> fusion of TN and naviculocuneiform joints
What to consider in adult with chronic mid foot pain?
Spontaneous navicular AVN**
Operative vs nonop for Achilles tendon rupture?
How to reconstruct chronic rupture (>6 wks) with < 3 cm gap and >3cm gap?
Nonop = eviqualent strength*
may have higher re-rerupture rates (though now in question) –> not true if doing early functional rehab
FEWER COMPLICATIONS***
Chronic rupture
<3 cm gap: VY advancement
> 3cm: FHL transfer*
Requires functioning tibial nerve
Residual plantar flexion weakness at hallux (expected)*
Complications with Achilles tendon repair?
Wound healing = 5-10% Risk factors = smoking*** female steroids Open*** (vs perc)
Sural nerve injury* (more with perc*)
Haglund deformity/Achilles tendonitis - when to augment repair if requires surgery?
Augment with FHL* when >50% of Achilles is involved*
How do peroneal tendons subluxate/dislocate?
Longitudinal tear more common in which tendon?
Position of tendons?
Rapid DORSIFLEXION on an INVERTED foot* = rapid reflexive contraction of PL and PB*
Rapid contraction leads to injury to superior peroneal retinaculum***
Tear more common in peroneus brevis***
Brevis lies anterior and medial to longus at level of lateral malleolus*
Brevis behind bone, longus takes long way around*
At level of peroneal tubercle of calcaneus –> longus is INFERIOR and brevis is SUPERIOR***
Treatment of peroneal tears/dislocation?
Nonop: SLC with protected weight bearing –> poor success (50%)
Operative
Acute repair of superior peroneal retinaculum and deepening of fibular groove* –> elite athlete or if there is a LONGITUDINAL TEAR*
Groove deepening with soft tissue transfer and/or osteotomy
Chronic/recurrent dislocation*** (less able to reconstruct the SPR)
Must correct hind foot varus prior to any SPR recon procedure***
how to treat Peroneal brevis tear?
Dx?
Tx?
Same exam/findings as peroneal dislocation w/o instability
Dx: MRI is REQUIRED for dx***
Tx
Nonop: activity restriction and cam boot –> high failure rate
Operative
Core repair and tubularization of tendon –> simple tears**
Debridement of tendon w/ tenodeiss of distal and proximal ends to peroneus longus or recon with allograft*** –> complex tears w/ multiple longitudinal tears and significant tendinitis (>50% tendon involved)
Debridement of both longus and brevis w/ allograft or FHL** or FDL** transfer (to 5th metatarsal)**
Hindfoot osteotomy w/ peroneal tendon pathology –> varus hind foot contributes to peroneal pathology –> calc osteotomy or subtalar arthrodesis ***
Accessory muscle that can be seen in peroneal compartment?
Peroneus quartus***
Arises from peroneus brevis, present in 20% patients, ass’d w/ lateral ankle pain and peroneal tendon sx –> mass effect w/in peroneal tendon sheath**
Tx of tib anterior rupture?
Direct repair if < 6 weeks***
Recon if >6 weeks
augment with autograft (hamstring, plantaris etc) may be necessary vs EHL split transfer**
After either repair or recon will have some residual weakness***
Most common pathogen causing osteomyelitis after puncture through shoe?
Soft tissue infection after puncture?
Osteomyelitis: pseudomonas***
Soft tissue infection: Staph aureus***
What is 1st line tx for plantar fascia rupture?
Cast immobilization for 3-6 wks***