Foot and Ankle Flashcards
Where is the watershed area of the PTT?
2-6 cm proximal to the navicular
Obese patient comes in with feet that look like this? How can you stage this?
-
Stage I - Tenosynovitis
- No deformity
- (+) single-leg toe raise
-
Stage IIA - Flatfoot deformity
- Exam
- Flexible hindfoot
- (-) single-leg heel raise
- Mild sinus tarsi pain
-
Imaging
- Arch collapse deformity on imaging
- Exam
-
Stage IIB - Flatfoot deformity
- Exam
- Flexible hindfoot
- Forefoot abduction (“too many toes”)
- Imaging
- >40% talonavicular uncoverage
- Exam
-
Stage III
- Exam
- Flatfoot deformity
- Rigid forefoot abduction
- Rigid hindfoot valgus
- Imaging
- Arch collapse deformity
- Subtalar arthritis
- Exam
-
Stage IV
- Exam
- Flatfoot deformity
- Rigid forefoot abduction
- Rigid hindfoot valgus
- Deltoid ligament compromise
- Ankle pain
- Imaging
- Arch collapse deformity
- Subtalar arthritis
- Talar tilt in ankle mortise
- Exam
Difference between adult and juvinile hallux valgus
- often bilateral and familial
- pain usually not primary complaint
- varus of first MT with widened IMA usually present
- DMAA usually increased
- often associated with flexible flatfoot
- complications
- recurrence is most common complication (>50%)
- overcorrection
- hallux varus
Risk factors for hallux valgus
-
intrinsic
- genetic predisposition
- ligamentous laxity
- convex metatarsal head
- pes planus
- rheumatoid arthritis
- cerebral palsy
-
extrinsic
- shoes with high heel and narrow toe box
Pathoanatomy of hallux valgus
- valgus deviation promotes varus position of metatarsal
- sesamoid complex becomes lateral to the metatarsal head, which moves medially
- medial MTP joint capsule becomes stretched and attenuated while the lateral capsule becomes contracted
- adductor tendon becomes deforming force
- inserts on fibular sesamoid
- lateral deviation of EHL
- plantar and lateral migration of the abductor hallucis causes muscle to plantar flex and pronate phalanx
- windlass mechanism becomes less effective
- leads to transfer metatarsalgia
Radiographs for hallux valgus
-
views
- weight bearing AP and Lat
-
sesamoid view can be useful
- displacement of sesamoids
- often displaced laterally
- joint congruency and degenerative changes can be evaluated
-
radiographic parameters (see below) guide treatment
-
Hallux valgus (HVA)
- Long axis of 1st MT and prox. phal.
- Identifies MTP deformity
- Normal = < 15°
-
Intermetatarsal angle (IMA)
- Between long axis of 1st and 2nd MT
- Normal = < 9°
-
Distal metatarsal articular (DMAA)
- Between 1st MT long. axis and line through base of of distal articular cap
- Identifies MTP joint incongruity
- Normal = < 15°
-
Hallux valgus interphalangeus (HVI)
- Between long. axis of distal phalanx and proximal phalanx
- Normal = < 10 °
-
Hallux valgus (HVA)
Approach to adolescent bunions
- best to wait until skeletal maturity to operate
- can not perform metatarsal osteotomies if physis is open (cuneiform osteotomy OK)
- surgery indicated in symptomatic patients with an IMA > 10° and HVA of > 20°
- severe deformity with a DMAA > 20 perform a double MT osteotomy
- technique
- soft tissue procedure alone not successful
- similar to adults if physis is closed (except in severe deformity)
Options for treatment of hallux valgus
-
Nonoperative
- shoe modification/ pads/ orthoses
- silastic spacer
- orthoses more helpful in patients with pes planus or metatarsalgia
-
Soft Tissue Procedure - modified McBride
- never appropriate in isolation
- in conjunction with medial eminence resection osteotomy
- release medial capsule of 2nd MTP; can be sutured to lateral capsule of 1st
-
adductor hallucis is released and interposed
- Can be left to scar down
- Transverse intertarsal ligament is releases which attaches to the fibular sesamoid
- Don’t resect the fibular sesamoid as was done with the original McBride or you will get hallux varus
-
distal metatarsal osteotomy
- mild disease (HVA 20-40, IMA 10-13)
- distal metatarsal osteotomies include
- Chevron
- biplanar Chevron
- Mitchell
- may be combined with proximal phalanx osteotomy
-
proximal metatarsal osteotomy
- moderate disease (HVA >40°, IMA >13°)
- proximal metatarsal osteotomies include
- crescentric osteotomy
- Broomstick osteotomy
- Ludloff
- Scarf
-
double (proximal and distal) osteotomy
- severe disease (HVA 41-50°, IMA 16-20°)
- DMAA > 15
- Scarf + chevron
- Lapidus + Akin
-
first cuneiform osteotomy
- severe deformity in young patient with open physis
-
Lapidus procedure (1st metatarsocuneiform arthrodesis)
- severe deformity
- Metatarsus primus varus
- hypermobile 1st tarsometatarsal joint
-
MTP Arthrodesis
- Gout
- Rheumatoid arthritis
- Down’s syndrome
- cerebral palsy
- Severe DJD
- Ehler-Danlos
- Resection arthroplasty
-
proximal phalanx (Keller) resection arthroplasty
- largely abandoned
- still indicated in some elderly patient with reduced function demands
Complications associated with HV
-
Recurrence
- most common cause of failure is insufficient preoperative assessment and failure to follow indications
- e.g., failure to recognize DMAA > 15°
- e.g., failure to do adequate distal soft tissue realignment
- more common in juvenile/adolescent population
- noncompliant patient that bears weight
- most common cause of failure is insufficient preoperative assessment and failure to follow indications
-
Avascular necrosis
- medial capsulotomy is primary insult to blood flow to metatarsal head
- distal metatarsal oseotomy and lateral soft tissue release inconjuction do not increase risk for AVN
-
Dorsal malunion with transfer metatarsalgia
- due to overload of lesser metatarsal heads
- risk associated with
- Lapidus
- proximal crescentric osteotomies
-
Hallux Varus
- caused by
- overcorrection of 1st IMA
- excessive lateral capsular release with overtightening of medial capsule
- overresection of medial first metatarsal head
- lateral sesamoidectomy
- caused by
-
Cock up toe deformity
- due to injury of FHL
- most severe complication with Keller resection
-
2nd MT transfer metatarsalgia
- often seen concomitant with hallux valgus
- shortening metatarsal osteotomy (Weil) indicated with extensor tendon and capsular release
-
Neuropraxia
- Painful incisional neuromas after bunion surgery frequently involve the dorsomedial cutaneous branch of the superficial peroneal nerve.
- This is the medial branch of the superficial peroneal nerve that terminates as the dorsomedial cutaneous nerve to the hallux. Branches of the deep peroneal nerve to this area are rare, and no branches to this area exist from the sural nerve. The saphenous nerve branches are generally more proximal, and the medial plantar nerve lies plantarly.
Iatrogenic causes of this deformity
- overcorrection of 1st IMA
- excessive lateral capsular release with overtightening of medial capsule
- overresection of medial first metatarsal head
- lateral sesamoidectomy
Treatment
-
Nonoperative
- shoe modifications to accommodate the deformity
- extra depth and wider more flexible toe box
- placing pads over prominent areas
- taping or splinting the deformity
-
Abductor hallucis release and transfer of EHL or EHB to proximal phalanx
-
indications
- flexible deformities
-
technique
- transfer portion of EHL or EHB under the transverse intermetatarsal ligament to the distal metatarsal neck (from lateral to medial) distal portion of tendon left intact, creating static stabilizer
-
indications
-
First MTP arthrodesis
-
indications
- fixed deformity
- significant arthrosis
-
indications
Classification of Hallux Rigidus
Cougling and Shurnas
-
Grade 0
- Stiffness with normal XR
-
Grade 1
- mild pain at extremes of motion
- mild dorsal osteophyte, normal joint space
-
Grade 2
- moderate pain with range of motion increasingly more constant
- moderate dorsal osteophyte,
-
Grade 3
- significant stiffness, pain at extreme ROM, no pain at mid-range
- severe dorsal osteophyte, >50% joint space narrowing
-
Grade 4
- significant stiffness, pain at extreme ROM, pain at mid-range of motion
- same as grade III
Options for treatment
Hallus Rigidus
- *Steroid injections are often ineffective and can adversely affect the cartilage and is not recommended
-
NSAIDS, activity modification & orthotics
- grade 0 and 1 disease
-
activity modifications
- avoid activities that lead to excessive great toe dorsiflexion
- types of orthotics
- Morton’s extension with stiff foot plate is the mainstay of treatment
- stiff sole shoe and shoe box stretching may also be used
-
Joint debridement and synovectomy
- patients with acute osteochondral or chondral defects
-
Dorsal cheilectomy - common first approach, high success rates
- grade 1 and 2 disease (with reports of treating even up to grade 4)
- pain with dorsiflexion is an indicator of good results with dorsal cheilectomy
- shoe wear irritation from dorsal prominence and pain (ideal candidate)
-
contraindication
- pain mid-range of the joint during passive motion (grade IV)
-
technique
- remove 25-30% of the dorsal aspect of the metatarsal head along with dorsal osteophyte resection
- the goal of surgery is to obtain 70% to 90% dorsiflexion intraoperatively
-
Moberg procedure (dorsal closing wedge osteotomy of the proximal phalanx)
- Sometimes done in conjunction with cheilectomy
- runners with reduced dorsiflexion (60° is needed to run)
- Alternatively a proximal MT osteotomy can be used to improve dorsiflexion as a joint salvage procedure, however is not recommended and is associated with metatarsalgia
- failure of cheilectomy to provide at least 30 to 40 degrees of motion
-
technique
- increases dorsiflexion by decreasing the plantar flexion arc of motion
-
Keller Procedure (resection arthroplasty)
- elderly, low demand patients with significant joint degeneration and loss of motion (>70)
- contraindicated in patients with pre-existing rigid hyperextension deformity of 1st MTP joint
-
technique
- involves removing the base of the first proximal phalanx
-
Complications
- requires appropirate patient selection and minimal resection
- risk of hyperextension (cock-up deformity)
- weakness with push-off
- transfer metatarsalgia (decreased with capsular interposition)
- IP arthroplasty has poor results and currently not recommended until further explored
- Seems to do better with intact plantar plate and FDB transfer
-
MTP arthroplasty
- indications controversial
-
technique
- capsular interpositonal arthroplasty gaining popularity
- silicone implants are not recommended due to poor long-term results
- Cobalt chrome with titanium plasma spray total joint and hemi arthroplasty are available but often loosen and are unreliable
-
outcomes
- silicone implants may have a good short term satisfaction rate but are currently not recommended
- osteolysis and synovitis cause mid to long term pain and joint destruction
- Total joint components have increased loosening and also are currently controversial and not often used
-
MTP joint arthrodesis - best definative option for failed chilectomy, in some patients with more severe disease can go straight to this
- grade 3 and 4 disease (significant joint arthritis)
- most common procedure for hallux rigidus
-
outcomes
- 70% to 100% fusion rate
- 15% of patients experience degeneration of IP joint after surgery (mostly asymptomatic)
Strongest construct for first MTP arthrodesis
dorsal plate with compression screw is biomechanically strongest construct
Risk factors for achilles rupture
Age
Steroids
Cipro
Eccentric muscle contraction
Treatment options for acute achilles rupture
-
Epidemiology
- men
- 30-40
- 4-6 cm above calcaneal insertion
-
Nonoperative
- functional bracing/casting in resting equinus (20 deg plantar flexion) with protected early functional rehab
-
indications
- sedentary patients
- elderly patients
- medically frail patients
- patient desires to avoid surgery
- increased risk of rerupture
-
outcomes
- patient will have decreased plantar flexion strength
- Increased risk of re-rupture
-
End-to-end Achilles tendon repair
- acute rupture (< 3 months)
-
technique
- Posteromedial incision
- Avoid or beware sural nerve
- Carefully incise periotenon
- Find each end, debride and perform and end to end repair using krochow technique and nonabsorbable suture
- Oversew the peritenon with 4-0 absorbable sutures
-
outcomes
- decreased re-rupture rate
- increase plantar flexion strength
-
disadvantages
- skin complications including infection, sloughing (5-10%)
- risk factors for wound complications included
- tobacco abuse
- steroid use
- diabetes mellitus
- female sex
- sural nerve injury
-
rehab
- initially immobilize in 20° of plantar flexion to decrease tension on skin and protect tendon repair
- functional rehabilitation during treatment improves range of motion and outcome
-
percutaneous repair
- weaker and not recommended
- sural nerve at highest risk for injury
Indications for non-operative treatment of achilles rupture
sedentary patients
elderly patients
medically frail patients
patient desires to avoid surgery
increased risk of rerupture
Increased risk of wound complications of achilles repair
tobacco abuse
steroid use
diabetes mellitus
female sex
sural nerve injury
obesity
Options for treatment of chronic achilles tear or re-rupture
-
Nonoperative
- physical therapy - toe strengthening, gait training
- AFO
- Primary repair < 3 cm
-
Reconstruction with VY advancement
- defects 3-5 cm
- Posteomedial incision extended proxiamlly to MC junction
- Debride tendon edges
- Fashion two flaps 1cm wide and 7-8cm long
- Advance the tendon to allow end-end repair and close the proximal incision of the tendon
-
FHL transfer
- defects > 5 cm
- Prone position with tourniquette
- Posterio-medial incision protecting NV bundle
- Separate medial incision to relesae the tendon at the knot of henry
- Some will harvest from the level of the joint
- excise degenerative tendon edges
- transfer FHL through osseous tunnels in the calcaneus, weave FHL to native achilles tendon
- >10cm = Allograft
-
Gastroc turndown
- another option but a large procedure
Complications associated with treatment of achilles
-
Dehisence/Infection
- ESR, CRP, WBC
- Consult ID and Plastics
- OR - I&D, deep cultures, VAC or free flap
- Directed IV abx until normal ESR/CRP
- Re-rupture
- Sural nerve palsy
Differential for Chronic Achilles inflammation
-
Paratenonitis
- Inflammation of the peritendinous structures, including the paratenon and septum
-
Tendinosis
- Asymptomatic degeneration of tendon without inflammation, with regional focal loss of tendon structure
-
Paratenonitis with tendinosis
- Inflammation of the peritendinous structures along with intratendinous degeneration
-
Retrocalcaneal bursitis
- Mechanical irritation of the retrocalcaneal bursa
- Younger patient, shoe wear
- haglund
-
Insertional tendinosis
- Inflammatory process within the tendinous insertion of the Achilles tendon
- middle age, boney enlargement
- tendon calcification
Middle aged woman with chronic heel pain. Differential? Likely Diagnosis? Helpful imaging?
Insertional Tendonitis
-
Differential
- insertional tendonitis
- tendonosis
- retrocalcaneal bursitis
-
Pain and tendon thickening at insertion of Achilles tendon
- repetitive trauma leads to inflammation followed by cartilaginous then bony metaplasia
-
History
- Take a complete and AMPLE history
- occurs in middle-aged and elderly patients with a tight heel cord
- symptoms
- posterior heel pain, swelling, burning, and stiffness
- shoe wear pain due to direct pressure - pump bump
- progressive bony enlargement of calcaneus at insertion site
-
Physical exam
- Examine - boney enlargement at insertion
- Palpate - midline tenderness at insertion site of Achilles tendon
- Move - reduced passive and active ROM
-
AP, lateral and oblique views of the foot
- lateral foot shows bone spur and intratendinous calcification
-
MRI and ultrasound
- can demonstrate amount of degeneration
- Early - fluid around the tendon
- Late - intratendonous calcification, degeneration of the tendon
Treatment of Insertional Achilles Tendonitis
-
activity modification, shoe wear modification, therapy
- first line of treatment
- techniques
- physical therapy with eccentric training
- Challenges muscle, to strengthen, promote repair and increase metabolic activity
- gastrocnemius-soleus stretching
- shoe wear
- heel sleeves and pads (mainstay of nonoperative treatment)
- small heel lift
- locked ankle AFO for 6-9 months (if other nonoperative modalities fail)
- physical therapy with eccentric training
-
retrocalcaneal bursa excision, debridement of diseased tendon, calcaneal bony prominence resection
-
indications
- failure of nonoperative management
- technique
- midline, lateral, or medial J-shaped incisions
-
indications
-
tendon augmentation or transfer (FDL, FHL, or PB) vs. suture anchor repair
-
indications
- when > 50% of Achilles tendon insertion must be removed
-
indications
Young patient with chronic heel pain. Differential? Likely diagnosis? Helpful imaging?
Retrocalcaneal bursitis
-
Differential
- insertional tendonitis
- retrocalcaneal bursitis
- tendosis
-
History
- Take a complete and ample history (social, sports, smoking, PMhx, meds, allergies)
- more common in young patients
- Due to rubbing on shoes
-
Physical exam
- Examine
- Palpate
- Two finger squeeze = pain localized to anterior and 2 to 3 cm proximal to the Achilles tendon insertion
- fullness and tenderness medial and lateral to tendon
- Pump bump = bony prominence at Achilles insertion
- Move
- pain with dorsiflexion (compresses the space)
- Silverskiold
-
AP, lateral, oblique of the foot
- lateral of foot demonstrates Haglund deformity
- Loss of kager triangle due to bursitis
- Swelling of tendon >9mm
- _2cm above the joint lin_e
-
MRI
- rarely needed
Treatment of retrocalcaneal bursitis
-
activity modification, shoe wear modification, therapy, NSAIDs
- first line of treatment
-
techniques
- ice
- shoewear - external padding of Achilles tendon
- PT
- no injections
-
Retrocalcaneal bursa excision and resection of Haglund deformity
- disease refractory to nonoperative management
-
technique
- midline, lateral, or medial J-shaped incision
Mechanism of Achilles Tendonosis
- overuse - common in soccer players
- imbalance of dorsiflexors and plantar flexors
- poor technique
- poor tendon blood supply - watershed area
- 2-6cm proximal to insertion
- genetic predisposition
- fluoroquinolone antibiotics
- inflammatory arthropathy
Classification of achilles TENDONOSIS
-
Achilles tendinosis
- tendon thickening
- thought to be caused by anaerobic degeneration in portion of tendon with poor blood supply
- Get a mucoid degeneration of the tendon due to age or reduced vascularity
- Inability to heal with repetative microtrauma, often seen after rupture and can be painless
- Especially middle age men who increase their activity
-
Achilles paratenonitis
- involves inflammation of tendon sheath
- Younger, due to repetative injury with inflammation around the tendon
- Runners, shoe wear issues, young athletes who overtrain
-
Tendinosis with paratenonitis
- Progression of disease = paratenonosis < paratenonosis with tendonitis < tendonitis alone
- Usually stranding within the tendon shows starting to develop tendonitis
- The further along the progression, the less likely to respond to therapy
Younger patient with chronic heel pain. Differential? Likely diagnosis? Helpful imaging?
Achilles Tendonosis
-
Differnetial
- insertional tendonitis
- retrocalcaneal bursitis
- achilles tendonosis
- peritenonitis
- tendonosis
- combined
-
History
- Take a complete and AMPLE history
- Age - Young (paratenonosis), old (tendinosis)
- symptoms - gradual onset
- Pain with activity, pain with ADL (will gradually become more painful as process continues)
- Pain more proximal with increasing severity as time goes on
- pain, swelling, warmth
- worse symptoms with activity
- difficulty running
- Minimal pain - think tendonitis
- PMHx - obesity, HTN, diabetes associated with tendionsis
-
Physical exam
- Examine, Palpate - tendon thickening and tenderness 2 to 6 cm proximal to Achilles insertion
- Move - pain throughout entire range of motion
- Paratenonitis
- Limited ROM
- Pain is fixed through all ROM
- Paratenonitis
- Positive silverskiold test
- US - fluid around the tendon with hypoechoic regions
-
MRI
- disorganized tissue will show up as intrasubstance intermediate signal intensity
- thickened tendon
- paratendinosis
- Fusiform swelling and high intesity with-in tendon (reflective of mucoid degeneration of tendinosis)
- chronic rupture will show a hypoechoic region between tendon ends
Options for treatment of achilles tendonosis
-
activity modification, shoe wear modification, physiotherapy, NSAIDs
- first line of treatment
-
techniques
- Retraining
- physical therapy with eccentric training
- Gastroc stretching
- shoewear
- heel lifts or shock absorber
- cast or removable boot (severe disease)
- Orthoses to correct pronation (tendonitis)
-
outcomes
- nonoperative management is 65% to 90% successful
-
glyceryl trinitrate patches, prolotherapy, and aprotinin injections
- Theory is injections to break down fibrous tissue - NOT appropriate for tenodonitis, only paratenonitis
-
indications
- evolving indications due to lack of evidence at this time
-
**Risks for failing non-op
- Age
- Duration of symptoms
- Degree of degeneration
-
Percutaneous tenotomies
- longitudinal tenotomy made in the degenerative area
- strip the anterior Achilles tendon with a large suture to free any adhesions
-
open excision of degenerative tendon with tubularization
- moderate to severe disease that is refractory to non-op treatment
-
Technique
- Posterior incision with development of full thickness flaps
- Incise paratenon and debride posterior, medial and lateral portion of the tendon
-
outcomes
- 70% to 100% successful
-
tendon transfer (FHL, FDL, or PB)
- This is not used for paratenonosis, only for tendonitis
-
indications
- degeneration of >50% of the Achilles tendon
- >55 years of age
- MRI evidence of diffuse tendon thickening without a focal area of disease
Risk of failing non-operative treatment for achilles tendonosis
Age
Duration of symptoms
Degree of degeneration
Indications for FDL transfer in achilles tendonosis
- degeneration of >50% of the Achilles tendon
- >55 years of age
- MRI evidence of diffuse tendon thickening without a focal area of disease
Name as many ossicles of the feet as you can
- Up to 40 accessory ossicles and multiple sesamoids have been described in the foot and ankle
-
Definition
- accessory ossicles - are secondary ossification centers that remain separated from the normal bone
- sesamoids - are bones that are incorporated into tendons and move with normal and abnormal tendon motion
-
Most common ossicles
- os trigonum
- accessory navicular (os tibiale externum)
- os intermetatarseum
-
Most common sesamoids
-
os peroneum
- located in the peroneus longus tendon
-
hallux sesamoids
- located in the flexor hallucis brevis tendon at the base of the 1st metatarsal head
-
os peroneum
-
Os trigonum
- 10-25%
- Posterior ankle impingement, FHL entrapment
- DDx - Shepherd’s fracture
-
Type II accessory navicular
- 2-12%
- Posterior tibial tendon dysfunction
- DDx - Navicular tuberosity avulsion frx, type I accessory navicular
-
Os subfibulare
- 2%
- Painful os subfibulare
- DDx - Lateral malleolus avulsion frx
-
Os peroneum
- 9-20%
- Painful os peroneum, fracture, diastasis
- DDx - Painful os vesalianum, bipartite os peroneum
-
Os vesalianum
- 2%
- Painful os vesalianum
- Ddx - Avulsion frx of the 5th metatarsal base
-
Hallux sesamoids
- ~100%
- Fracture, stress fracture
- DDx - Bipartite tibial sesamoid
Dancer, pain with “en pointe” plantarflexion. Diagnosis? Treatment?
Os Trigonum
-
Definition
- sesamoid bone representing the seperated posterolateral tubercle of the talus
- usually asymptomatic, but can become symptomatic and cause os trigonum syndrome
-
Epidemiology
- 10-25% of the population have os trigonum
- commonly symptomatic in ballet dancers due to extreme plantar flexion (“en pointe” toe position)
-
Pathophysiology of os trigonum syndrome
- repetitive microtrauma (ankle plantarflexion)
- may present as a stress fracture
- acute forced plantarflexion
- may present as an acute fracture
- repetitive microtrauma (ankle plantarflexion)
-
Associated conditions
- FHL tenosynovitis or entrapment
-
Osteology
- the secondary ossification center forms posterior to the talus between 8-13yrs
- normally fuses with talus within 1yr
- if the ossicle fails to fuse, it articulates with the talus through a synchondrosis
- the os lies lateral to FHL, tibial nerve, PTT, and posterior tibial artery
-
Presentation
- pain in “en pointe” position
-
physical exam
- posterior lateral ankle pain with passive ankle plantar flexion
- may have swelling and tenderness over FHL if associated with FHL tendinitis
-
radiographs
- lateral radiograph with foot in plantar flexion
- shows os trigonum impinged between posterior tibial malleolus and calcaneal tuberosity
- os trigonum can be round, oval or triangular and of variable size
-
MRI
- shows os trigonum and associated inflammation and edema in FHL tendon
-
Differential diagnosis
- fracture of the posterior process of the talus (Shepherd’s fracture)
- FHL and posterior tibialis tendinitis
- produce posterior medial ankle pain and tenderness
- NSAIDS, rest, immobilization, restricted weightbearing
-
surgical excision
- if nonoperative management fails
-
techniques
- through open lateral approach or posterior ankle arthroscopy
Risk factors for diabetic ulcers
-
factors associated with decreased healing potential
- uncontrolled hyperglycemia
- inability to offload the affected area
- poor circulation
- infection
- poor nutrition
-
factors associated with increased healing potential
- serum albumin > 3.0 g/dL
- total lymphocyte count > 1,000/mm3
-
associated conditions
-
angiopathy
- lesser effect than neuropathy
- >60% of diabetic ulcers have decreased blow flow due to peripheral vascular disease
-
infection / osteomyelitis
- high rates of associated osteomyelitis if bone is able to be probed, or is exposed at the base of the ulcer
- 67% of ulcers that probe to bone have osteomyelitis
- Organisms (polymicrobial)
- S. aureus most common
- gram negative in setting of abx
-
angiopathy
Wagner classification diabetic foot ulcer
-
Grade 0
- Skin intact but bony deformities lead to “foot at risk”
- Shoe modifications with serial exams
-
Grade 1
- Superficial ulcer
- Office debridement and contact casting
-
Grade 2
- Deeper, full thickness extension
- Operative formal debridement and contact casting
-
Grade 3
- Deep abscess formation or osteomyelitis
- Operative formal debridement and contact casting
-
Grade 4
- Partial Gangrene of forefoot
- Local vs. larger amputation
-
Grade 5
- Extensive Gangrene
- Amputation
Brodsky classification diabetic foot ulcer
-
Depth
- 0
- At risk foot, no ulceration
- Patient education, accommodative footwear, regular clinical examination
- 1
- Superficial ulceration, not infected
- Off-loading with total contact cast, walking brace or special footwear
- 2
- Deep ulceration, exposing tendons or joints
- Surgical debridement, wound care, off-loading, culture-specific antibiotics
- 3
- Extensive ulceration or abscess
- Debridement or partial amputation, off-loading, culture-specific antibiotics
- 0
-
Ischemia
- A
- Not ischemic
- B
- Ischemia without gangrene
- Non-invasive vascular testing and vascular reconstruction with angioplasty/bypass
- C
- Partial forefoot gangrene
- Vascular reconstruction and partial foot amputation
- A
Work-up for this patient
Diabetic Ulcer
-
History
- often painless
- time, first noticed, treatment
- hx of neuropathy or associated diabetic symptoms
- sugar control history
- PMHx
-
Physical exam
-
depth of ulcer
- probe from bone
- presence of infection
- look for cellulities, pus
- check for gangrene
- Silfverskiöld test
-
Semmes-Winstein
- __go from smaller to larger
- 5.07 = diabetes
-
Circulation
- assess dorsalis pedis and posterior tibialis pulses
- ABI’s > 0.45
- toe pressure >40mm Hg
-
Transcutaneous oxygen pressures (TcpO2)
- considered gold standard to assess wound healing potential
- > 30 mm Hg is a good sign of healing potential
-
depth of ulcer
-
Labs
- WBC > 1000
- ESR, CRP
- albumin > 3.0
- HgA1C
-
Radiographs
- AP, lateral, and oblique of foot and ankle
- evidence of flatfoot, boney prominence, charcot joint
- OM
-
MRI
- useful to determine presence of osteomyelitis
-
Bone scan
- obtain with technetium Tc99m, gallium (Ga)67, or indium (In) 111
- useful to differentiate between
- soft tissue infection
- osteomyelitis
- Charcot arthropathy
- Bone biopsy
- If grade 3 or you suspect infection
What are important factors for wound healing
- albumin > 3.0 g/dl
- lymphocyte > 1000 mm3
-
transcutaneous oxygen > 30mmHg
- __gold standard
- ABI > 0.45
- toe pressure > 40mmHg
Treatment plan for diabetic foot
-
General - factors important in deciding a treatment plan include
- angiopathic vs. neuropathic
- deep vs. superficial
- +/- osteomyelitis, antibiotics based on bone biopsy culture sensitivities
- +/- pyarthrosis
-
Nonoperative
-
wound care
- goals of wound care and dressings
- provide moist environment
- absorb exudate
- act as a barrier
- off-load pressure at ulcer
- goals of wound care and dressings
-
shoe modifications
- includes deep or wide shoes, custom insoles, rocker bottom soles, etc.
- of the available shoe only modifications, rocker sole shoes best reduce the plantar pressure on the forefoot
- medicare will cover modifications and custom shoes/insoles yearly
-
wound care
-
total contact casting (TCC)
- gold standard for mechanical relief plantar ulcerations
-
technique
- weekly change with wound care
- often necessary for up to 4 months
- TCC followed by Charcot restraint walker then custom shoe
-
pneumatic walking brace
- alternative to TCC, same principal
- allows better wound surveillance
- compliance is an issue with significant foot deformity
-
outcomes
- if ulcer recurs, it is typically 3-4 weeks after cast removal
-
surgical debridement, antibiotics, local wound care, contact casting
- grade 3 or greater ulcers should undergo I&D with antibiotic treatment before casting
-
outcomes
- high rates of associated osteomyelitis if bone is able to be probed, or is exposed at the base of the ulcer
-
ostectomy +/- TAL (tendon-achilles lengthening)
- bony prominence causing internal pressure
-
technique
- TAL indicated if tight achilles
- several studies have shown TAL to be effective to help heal and prevent recurrence of plantar forefoot ulcers
-
partial calcanectomy +/- TAL
- large heel ulcers with associated calcaneal osteomyelitis
-
outcomes
- preserves limb length and decreases morbidity compared to higher level amputations
-
syme amputation
- forefoot gangrene and a palpable posterior tibial artery pulse
Causes of charcot joint
- Diabetes
- syrnix/syringomelia (UE)
- spinal tumor (LE)
- EtOH
- syphilis (knee)
- leprosy
- dialysis
- congential insensitivity to pain
Pathophysiology
Charcot Foot
-
Mechanism
- Charcot flare may occur as a response to local trauma in a patent with neuropathy
- Charcot neurpathy of midfoot may occur following ORIF of ankle fracture
-
Epidemiology
- 50% of diabetics have neuropathy within 25 years of diagnosis
- sensory neuropathy is most common (70%)
- motor neuropathy presents as claw toes
- intrinsic weakness and Achilles tendon contracture
-
Type I diabetes
- Charcot neuropathy presents in 5th decade (duration of diabetes of 20-24years)
-
Type II diabetes
- Charcot neuropathy presents in 6th decade (duration of diabetes of 5-9 years)
- 50% of diabetics have neuropathy within 25 years of diagnosis
-
incidence
- 0.1-0.4% of patients with diabetes
- 7.5% of patients with diabetes and neuropathy
- 9% to 35% have bilateral disease
-
Pathophysiology
-
neuropathy
- severe sequelae result from presence of both sensory and autonomic involvment
- sensory dysfunction leads to lack of protective sensation.
- autonomic dysfunction leads to drying of skin due to lack of normal glandular function.
-
angiopathy
- < 33% of patients with diabetic ulcers have decreased arterial flow
-
neuropathy
-
Theories
-
neuroanatomic
- insensate joints subjected to repetitive microtrauma
-
neurovascular
- autonomic dysfunction increases blood flow through AV shunting, resulting in bone resorption and weakening
-
neuroanatomic
-
Ulcer location
-
forefoot
- skin breakdown secondary to increased pressure, exacerbated by tight Achilles tendon or gastrocnemius
- treatment is total contact casting
-
midfoot
- increased pressure from architectural collapse
- treatment is resection of offending bone (cuboid or cuneiform) through a separate incision from the ulcer
-
hindfoot
- vascular etiology
-
forefoot
-
Molecular biology
- RANK/RANKL/OPG triad pathway thought to be involved
- involves IL-1 and TNFa
- markers
- bone turnover markers increased (increased osteoclastic activity)
- bone formation markers unchanged
Brodsky classification charcot foot
-
Type 1: involves tarsometatarsal and naviculocuneiform joints
- most common location (60% of cases)
- collapse leads to fixed rocker-bottom foot with valgus angulation
-
Type 2: involves subtalar, talonavicular or calcaneocuboid joints
- 10% of cases
- unstable, requires long periods of immobilization (up to 2 years)
-
Type 3A: involves tibiotalar joint
- 20% of cases
- late varus or valgus deformity produces ulceration and osteomyelitis of malleoli
-
Type 3B: follows fracture of calcaneal tuberosity
- late deformity results in distal foot changes or proximal migration of the tuberosity
- Type 4: involves a combination of areas
- Type 5: occurs solely within forefoot
Eichenholtz classification charcot foot
-
Stage 0
- Joint edema
- Radiographs are negative
- Bone scan may be positive in all stages
-
Stage 1 - fragmentation
- Joint edema
- Radiographs show osseous fragmentation with joint dislocation
-
Stage 2 - coalescence
- Decreased local edema
- Radiographs show coalescence of fragments and absorption of fine bone debris
-
Stage 3 - reconstruction
- No local edema
- Radiographs show consolidation and remodeling of fracture fragments
Diabetic patient comes in with painful foot. Work-up?
Charcot Foot
-
History
- Take a complete and AMPLE history
- Characterize the event - trauma?
- swollen foot and ankle
- pain in 50%, painless in 50%
- loss of function
- PMHx - diabetes (1 vs 2), length of time, PVD
-
Physical exam
-
Look
- swollen, warm, erythematous joint
- mimics infection
- skin temperature 3.3degC higher than unaffected side
- Put foot up on chair, if erythema resolves it’s charcot
- Look for any evidence of prominences or ulcerations
-
Feel
- joint may be mechanically unstable
- Silfverskiöld test
- Neuro
- Semmes-Winstein
- go from smaller to larger
- 5.07 = diabetes
- Semmes-Winstein
-
Circulation
- assess dorsalis pedis and posterior tibialis pulses
- ABI’s > 0.45
- toe pressure >40mm Hg
-
Transcutaneous oxygen pressures (TcpO2)
- considered gold standard to assess wound healing potential
- > 30 mm Hg is a good sign of healing potential
-
Look
-
Laboratory
- HgA1C
- ESR and WBC can be elevated making it difficult to differentiate from osteomyelitis
-
Wound healing levels
- absolute lymphocyte count >1500/mm3
- serum albumin >3.0g/dL
- ABI >0.45
- toe pressure >40mmHg
-
Wound culture
- obtain biopsy, ulcer curettage, or aspiration (not wound swab) to rule out osteomyelitis before starting antibiotics
-
Histology
- synovial hypertrophy
- detritic synovitis (cartilage and bone distributed in synovium)
-
Radiographs
- obtain standard AP and lateral of foot, complete ankle series
-
findings
- early changes
- degenerative changes may mimic osteoarthritis
- late changes
- obliteration of joint space
- fragmentation of both articular surfaces of a joint leading to subluxation or dislocation
- scattered “chunks” of bone in fibrous tissue
- surrounding soft tissue edema
- joint distension by fluid
- heterotopic ossification
- early changes
-
Bone scan
-
technetium bone scan
- may be misleading
- positive for neuropathic joint and osteomyelitis
-
indium WBC scan
- will be negative (cold) for neuropathic joints and positive (hot) for osteomyelitis
- this is a valuable study to differentiate from osteomyelitis
-
technetium bone scan
-
MRI
- best for differentiating abscess from soft-tissue swelling
- difficult to differentiate infection from Charcot arthropathy on MRI
- Angiography may be considered if there is though of PVD
Treatment approach?
Charcot Joint
- diabetic team consult for blood glucose management
-
contact casting, medications
-
technique
- use for 2-4 months, change every 2-4 weeks
- Hindfoot and ankle (Type 3) will require a longer immobilization
- Charcot restraint orthotic walker (CROW) boot can be used after contact casting
- later, can be fitted with custom shoe with orthotics
-
medications
- bisphosphonates - promising
- calcitonin
- neuropathic pain medications
- gabapentin
- antidepressants
- topical anesthetics
-
outcomes
- 75% healing rate
-
technique
-
resection of bony prominences (exostectomy) and TAL
-
indications
- suitable for patient with viable healing potential and stable deformity creating skin at risk of continued ulceration
-
technique
- goal is to acheive plantigrade foot that allows ambulation without skin compromise
-
indications
-
arthrodesis
-
indications
- for severe deformity
-
outcomes
- average time to fusion is 3 to 5 months
-
indications
-
amputations
-
indications
- severe deformity not ammenable to arthrodesis
- goal is for a partial or limited amputation if vascularity allows it
-
indications
Options for fixation for arthrodesis of charcot joint
-
internal fixation
- screw, pin, plate, tibiocalcaneal nail
- high complication rate
-
external fixation
-
indications
- morbid obesity
- poor bone quality
- poor soft-tissue envelope
- ulcers with underlying osteomyelitis
-
high complication rate (up to 70%)
- infection (superficial and deep)
- hardware malposition
- recurrent ulceration
- fracture
- commonest complication is pin track infection
-
indications
Acceptable amputation for charcot joint
acceptable limited amputation that lead to a functionable and braceable foot include (forefoot stability is preserved if not more than 2 rays are resected)
lateral three ray amputation
medial two ray amputation
two central ray amputation
Lisfranc (with TAL) amputation
Chopart amputation
Syme amputation
only perform in younger patient with good pulses at ankle)
Options for achilles tendon lengthening
What are the phases of gait?
-
Overview
- one gait cycle is measured from heel-strike to heel-strike
-
consists of
-
stance phase
- period of time that the foot is on the ground
- ~60% of one gait cycle is spent in stance
-
swing phase
- period of time that the foot is off the ground moving forward
- ~40% of one gait cycle is spent in swing
-
stance phase
-
Stance phase (“I Like My Tea Presweetened”)
-
initial contact
- occurs when foot contacts the ground
- FIRST ROCKER METATARSALGIA- heel - occurs only in the context of congenital deformity or tight heelcord
- muscular contractions
- hip extensors contract
-
loading response (initial double limb support)
- occurs after initial contact until elevation of opposite limb
- SECOND ROCKER - stiff ankle, plantarflexed MT will cause increase pressure threw the foot
- muscular contractions
- ankle dorsiflexors (tibialis anterior) contract eccentrically to control plantar flexion moment
- quads contracts to stabilize knee and counteract the flexion moment (about the knee)
-
mid-stance (single limb support)
- from elevation of opposite limb until both ankles are aligned in coronal plane
- muscular contractions
- hip extensors and quads undergo concentric contraction
-
terminal stance (single limb support)
- from when ankles are aligned to until the opposite to when heel strikes in contralateral limb
- muscular contractions
- toe flexors contract
- The post tib will invert the subtalar joint to lock the hindfoot and provide a solid lever arm for toe-off
- THIRD ROCKER - forefoot on ground - progressive MTP deformities
-
Pre-swing phase
- from initial contact of opposite limb to just prior to elevation of ipsilateral limb
- muscular contractions
- hip flexors contract to propel advancing limb
-
initial contact
-
swing phase (“In My Teapot”)
-
initial swing (toe off)
- from elevation of limb to point of maximal knee flexion
- muscular contractions
- hip flexors contract
-
mid-swing (foot clearance)
- following knee flexion to point where tibia is vertical
- muscular contractions
- ankle dorsiflexors contract to ensure foot clearance - mostly tib ant
- Anything comprimising tib ant will cause the extensors to fire to help recruit
- Tight gastrocs will increase subtalar extension with the knee in extension, plantar fascia and achilles are overloaded
-
terminal swing (tibia vertical)
- from point where tibia is vertical to just prior to initial contact
- muscular contractions
- hamstring muscles decelerate forward motion of thigh
-
initial swing (toe off)
Where is the center of gravity in the body
- 5cm anterior to S2 vertebral body
- displaced 5cm horizontally and 5cm vertically during adult male step
What are the determinants of gait?
-
pelvic rotation
- pelvis rotates 4 degrees medially (anteriorly) on swing side
- lengthens the limb as it prepares to accept weight
-
pelvic tilt
- pelvis drops 4 degrees on swing side
- lowers COG at midstance
-
knee flexion in stance
- early knee flexion (15 degrees) at heel strike
- lowers COG, decreasing energy expenditure
- also absorbs shock of heel strike
- early knee flexion (15 degrees) at heel strike
-
foot mechanisms
- ankle plantar flexion at heel strike and first part of stance
-
knee mechanisms
- at midstance, the knee extends as the ankle plantar flexes and foot supinates
- restores leg to original length
- reduces fall of pelvis at opposite heel strike
-
lateral displacement of pelvis
- pelvis shifts over stance limb
- COG must lie over base of support (stance limb)
Etiology and pathoanatomy
-
Etiology
-
Neuromuscular
- __CMT/HMSN
- CP
- stroke
- anterior horn cell
-
Traumatic
- __compartment syndrome
- crush
- talus nonunion
- peroneal nerve
- Idiopathic
- Residual clubfoot
-
Neuromuscular
-
Deformity caused by
- spasticity - contracted plantar fascia
- Peroneus longous is stronger than tibialis anterior - plantarflexes first ray
- Strong tibialis posterior, weak peroneus brevis
- Weak flexor intrinsics overpowered by strong extensor extrinsics
-
Pain
- Overloading of metatarsal heads - metatarsaliga
- Prone to ankle sprains, peroneal injury, IT syndrome, medial knee arthrosis
- Lateral stress fractures, claw toes, ankle impingement
Work-up for cavus foot
-
History
- Pain on the lateral side of the foot
- Stress fracture of the base of the fifth MT
- Lateral ankle instability (from varus)
- Metatarsaligia (distal migration of the fat pads)
- Early degeneration of the medial side of the ankle
- history for trauma, stroke, family history for HNMD
- Goals of the patient
- Pain on the lateral side of the foot
-
Physical exam
- Assess for Calluses along metatarsal heads and lateral foot
- Gait
- High stepping gait due to equinus contracture or foot drop
- Feel
- Assess for pain along any tendons
- Assess for pain along the ATFL or base 5th
- Assess the tripod of the foot
- Move
- Map the strength of each tendon, look for deficiency
- Feel stability of the ankle
-
Neuro exam
- Assess for bilateral pathology suggestive of CMT or polio
- Assess for UMN or LMN pathology
- Look at peroneal distribution
-
Peak-a-Boo
- Can see the heel from the front due to varus
-
Coleman block test
- flexible hindfoot will correct to neutral when block placed under lateral aspect of foot
-
Silverskiold
- Test for tight achilles/gastroc
- always remove shirt and look for spinal dysraphism
- Consider referal to neurologist
-
EMGs
- If you suspect a neuromuscular condition
-
Plain Radiographs
- AP
- Talo-1st metatarsal angle (0-3 deg)
- Measures the forefoot position
- Lateral
- Meary’s angle
- Calcaneal pitch
- Subtalar arthritis
- AP ankle
- Varus of talus under mortise - hindfoot
- Canale
- Can look for any varus malunion or evidence of previous fracture
- AP
- Bone scan or sequence of lidocaine injections might help to find the pathology
-
CT
- Can be done if there is presence of boney deformity
-
MRI
- To assess vascularity of talus or other bones
Approach to conservative treatment
-
Conservative - non-rigid deformity
-
Accomodative orthotics
- custom, full length
- __high shoe box for claw toes
- Recessed first ray
- Low arch support
- Heel cushion
- MT pad if metatarsalgia present
- Ankle brace for instability
- AFO for any foot drop or substantial weakness
- Baclofen, diazepam, Botulinum toxin
- PT - Gastrocnemius stretching, proprioceptive retraining
-
Address any associated injuries
- Stress fractures, ankle instability, peroneal tendon
-
Accomodative orthotics
-
general surgical indications
- Surgery should be delayed until progression of the deformity begins to cause symptoms and/or weakness of the muscular units resulting in contractures of the antagonistic muscle units
- Some will say you should do it right away because it is often a progressive deformity