Circulation of tissues within a closed osteofascial space are compromised by increased pressure within that space
Most common
- anterior leg compartment
- flexor compartment forearm
- deep posterior leg compartment
Prerequisite is volume restricting envelope
- fascia & skin
- POP
- dressings
1. Increased contents
Bleeding / edema
- fracture
- osteotomies
- crush injuries
- post - ischaemic swelling
2. Decreased size
Tight casts & dressings
Tight closure of fascial defects
Fracture reduction
Increased local tissue pressure increases pressure within intracompartmental veins
- local AV gradient is reduced
- causes decreased local perfusion secondary to Starling Forces
Metabolic tissues demands not met
- loss of tissue function & viability
- distal pulses remain as ICP < SBP
- digit capillary refill remains as venous return extracompartmental
1. Pain
- most important sign
- much great than expected
- masked by coma / neural injury
- unrelieved by opiates
2. Paraesthesia
- often early
- pins & needles or decreased sensation to light touch
- distribution important
- nerve of that compartment will be affected
3. Palpation
- swollen, tense compartment
4. Passive Stretch
- pain on passive stretch
- subjective
- complicated by underlying trauma
5. Paresis
- may be due to proximal nerve injury or guarding 2° to pain
6. Pulses
- pulse & capillary refill are normally present
Clinical Diagnosis
Tense compartment with pain +++
Pain on passive stretch
Intramuscular Pressure Measurement
Indications
1. Unresponsive
- head injury
- ventilated
2. Uncooperative
- children, drug abusers
3. Underlying peripheral nerve deficit
- tibial fracture with CPN nerve deficit
Techniques
1. Needle - Manometer Method (Whitesides)
- 18G needle is connected via a 3 way stop cock to an air filled 20 ml syringe
- air filled tubing which is connected to a Hg Manometer
- a small amount of saline sits in tube connected to needle
- compression of the syringe raises the pressure till saline flows into the compartment
- this is indicated by the meniscus moving
2. Arterial Pressure Transducer
- i.e. devices used in ICU to measure arterial blood pressure and CVP
- no need to inject fluid
- pressure in saline tube equalizes with compartment
- connect to Wick or Slit catheter
- slits have many longitudinal slits to equalize pressure in tube with compartment
3. Stryker Device
- Variation on 2
Interpretation
Matsen > 45 mmHg
Mubarek & Rorabeck > 30 mmHg
Whitesides - within 30mmHg of DBP
Remove all tight dressings
- splitting POP decreases pressure by 30%
- bivalving & cutting padding reduces pressure by another 55%
- elevate limb
Avoid hypotension
Ream without tourniquet
Full-length skin incision
Complete fasciotomy of all compartments
Assessment of muscle (colour / consistancy / contraction / bleeding)
Debridement dead muscle
Delayed DPC / graft
Anterolateral compartments
- incision halfway between crest of tibia & fibula
- identify and protect SPN
- expose lateral intermuscular septum (transverse cut)
- release Anterior & Lateral compartments
Posterior compartments
- incision 2 cm posterior to posterior margin of tibia
- identify and protect saphenous vein / nerve anteriorly
- identify septum between superficial & deep compartments
- release fascia over Gastro-Soleus (superficial posterior compartment)
- release deep posterior compartment which is located behind the tibia / FDL
Lateral incision beginning just posterior to fibula
- expose & protect CPN
- posteriorly release superficial posterior compartment
- release FHL (deep posterior compartment
- anteriorly expose and release anterolateral compartments after identifying SPN
4 interconnected compartments
- volar superficial
- volar deep (FDP / FPL / pronator quadratus)
- mobile wad (BR, ECRL, ECRB)
- extensor
Volar
- incision from medial elbow to carpal tunnel
- must release lacertus fibrosis and carpal tunnel
- divide fascia
- this will release superficial flexor muscles
- ensure release mobile wad
- ensure release FDP
Dorsal
- often volar release wil decompress dorsal compartment
- usually ulnar sided incision
- proximal over muscle belly
- distally is mostly tendons
Two dorsal incisions
- over MT 2 and MT 4
- release interossei compartments
Carpal tunnel incision
- release thenar / hypothenar / adductor
- release carpal tunnel
2 dorsal incisions
- over MT 2 and MT 4
- release 4 interossei compartments
Medial incision
- release medial / central and lateral compartments
- ischaemic muscles fibrose & contract
- causes deformity & stiffness
- nerves damaged with variable numbness