Limb compartments
- The deep fascia envelops the limbs
- Other fascial planes divide the limbs into compartments
- The forearm has two compartments
- The thigh has three compartments
- The lower leg therefore has four compartments
Compartment syndrome
- A condition in which the circulation and function of tissues within
a closed space is compromised by an increase in pressure within that
space
Pathophysiology
- The normal lower limb venous pressure is a few mmHg
- Normal intracompartmental pressures are in the range 0 - 10 mmHg
- Compartmental pressure does not interfere with blood flow
- Swelling within a facial compartment results in increased
intracompartmental pressure
- Initial venous compromise may progress to reduced capillary flow
- This exacerbates the ischaemic insult and further increases pressure
- A vicious cycle of increasing pressures can be initiated
- Arterial inflow rarely reduced unless pressure exceed systolic blood
pressure
- Irreversible muscle ischaemia will occur within 6 to 12 hours
- Surgical treatment within 6 hours of onset usually results in a
positive outcome
Aetiology
- Orthopaedic
- Tibial fractures (especially comminuted fractures)
- Forearm fractures
- Vascular
- Ischaemia-reperfusion injury
- Haemorrhage
- Phlegmasia caerulea dolens
- Iatrogenic
- Vascular puncture in anticoagulated patients
- Intravenous or intra-arterial drug injection
- Soft-tissue injury
- Prolonged limb compression
- Crush injury
- Burns
Clinical features
- Compartment syndromes are normally seen with 48 hours of injury
- Typical clinical features include:
- Increasing pain despite immobilisation of fracture
- Altered sensation in the distribution of nerves passing through
the compartment
- Muscle tenderness
- Excessive pain on passive movement
- Peripheral pulses may still be present
Pressure monitoring
- Intracompartmental pressure (ICP) can be measured by several means
including:
- Wick catheter
- Simple needle manometry
- Infusion techniques
- Pressure transducers
- Side-ported needles
- Critical pressure for diagnosing compartment syndrome unclear
- Different authors consider surgical intervention if:
- Absolute ICP greater than 30 mmHg
- Difference between diastolic pressure and ICP greater than 30 mmHg
- Difference between mean arterial pressure and ICP greater
than 40 mmHg
Treatment
- Remove constricting casts, splints etc
- Casts should be split on both sides and constricting dressings or
padding cut
- If no improvement prompt fasciotomies required
- Need to divide skin and deep fascia for the whole length of the
compartment
- Wounds should be left open
- May require delayed closure or skin grafting
Fasciotomies
- Several surgical approaches have been described
- The goal is prevention of disability
- Decompression should not be compromised by a desire for good
cosmesis
- All compartments should be decompressed
- Two incision required to decompress the 4 compartments of the lower
leg
- Skin incisions of about 15-20 cm in length are required
Picture provided by Wolfgang Fiel, Donauspital,
Vienna, Austria
Picture provided by Russell George, Texas Women's
Hospital, USA
Outcome
- Timely surgery produces a good functional outcome
- Delay results in muscle ischaemia and necrosis
-
Muscle fibrosis produces the typical Volkmann's ischaemic contracture
Fat embolism
- Due to fat entering torn venous channels at fracture site
- Chylomicrons may also aggregate due to lipase release
- Presents with pyrexia, tachycardia, tachypnoea, reduced
consciousness
- May develop petechial rash
- Clotting may be deranged with features of DIC
- Arterial gases show hypoxia and hypercapnia
- Patients may require ventilation
- Mortality can be as high as 15%
Bibliography
McQueen M M, Christie J,
Court-Brown C M. Acute
compartment syndrome in tibial diaphyseal fractures.
J Bone Joint Surg [Br] 1996;
78: 95-98
McQueen M M, Court-Brown C
M. Compartment monitoring in
tibial fractures. The
pressure threshold for decompression.
J Bone Joint Surg [Br] 1996;
78: 99-104.
Parisi D M, Koval K, Egol K. Fat embolism syndrome.
Am J Orthop 2002; 31: 507-512.
Pearse M, Nanchahal J. Acute Compartment syndrome of the
leg. Br Med J 2002; 325: 557-558.
Singh S, Trikha S P, Lewis J. Acute compartment
syndrome. Current orthopaedics 2004; 18: 468-476.
Tiwari A, Haq A I, Myint F, Hamilton G. Acute
compartment syndromes. Br J Surg 2002; 89:
397-412.
van Essen G J, McQueen M
M. Compartment syndrome in
the lower limb. Hosp Med
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