Compartment Syndrome

You are on night ward call and a nurse calls you to review a post operative patient for worsening leg pain. James, a 25 year old male, is day 1 post right intramedullary tibial nail. You have been called multiple times about James for pain relief. He has low pain tolerance and is suspected to use regular recreational drugs.

What questions would you ask the nurse?

1. Neurovascular observations - including capillary refill
2. Amount of analgesia used
3. Background

also consider:

• known bleeding disorder
• does he have a cast in situ

REMEMBER: compartment syndrome can occur wherever skeletal muscle is surrounded by fascia, including leg (similar to this case), forearm, hand, foot, thigh, buttocks, shoulder, etc
     
Pathophysiology of compartment syndrome

1. trauma/ soft tissue destruction
   
2. bleeding and oedema
3. increased interstitial pressure
4. vascular occlusion
5. myoneural compromise

Majority of cases are secondary to fractures

What are the 6 P's of Compartment Syndrome and what are late and early signs? Hint: think of the pathophysiology above (Stracciolini, Hammerberg 2015)

1. Pain on passive stress - early sign - most sensitive
2. Palpable swelling - woodlike
3. Paraesthesia -reduced sensation secondary to ischaemic nerve dysfunction
   
4. Poikilothermia 
5. Pallor - unusual finding
   
6. Peripheral pulses absent - late finding
   

Realistically the patient will complain of pain out of proportion, described as a deep ache or burning pain, deep ache or burning pain and potentially paraesthesia and muscle weakness (onset is usually 30minutes to 2 hours of acute compartment syndrome).

Interpreting Clinical Findings:

• Capillary refill becomes compromised if compartment pressure reaches 25-30mmHg of mean arterial pressure
• Pain develops with compartment pressure of 20-30mmHg
• Ischaemia occurs if compartment pressure reaches diastolic pressure

What are the 4 compartments of the leg and define what structures are within them?
1. Anterior Compartment:

• Function: dorsifllexion of foot and ankle
• Muscles within compartment: tibialis anterior, extensor hallucis longus, extensor digitorum longus, peroneus tertius

2. Lateral Compartment

• Function: plantarflexion and eversion of foot
• Muscles within compartment: peroneus (fibularis) longus, peroneus brevis
• Nerve: isolated lateral compartment syndrome would affect superficial peroneal nerve

3. Deep Posterior Compartment

• Function: plantarflexion and inversion of foot
• Muscles: tibialis posterior, felxor digitorum longus, flexor hallucis longus

4. Superfical Posterior Compartment

• Function: plantarflexion of foot and ankle
• Muscles: gastrocnemius, soleus, plantaris

REMEMBER: you will never get told off for removing a cast if you suspect compartment syndrome
How to measure compartment pressures?

How do I measure compartments?
3 methods are used frequently:
1. A handheld manometer (eg, Stryker device)
2. A simple needle manometer system, and
3. The wick or slit catheter technique
Both manometer methods involve injecting a small quantity of saline into a closed compartment and measuring the resistance from tissue pressure

The normal pressure of a tissue compartment falls between 0 and 8 mmHg (Klenerman L, 2007)

Procedure:
Should aim to measure pressures within 5cm of fracture site.

• Anterior Compartment: enter perpendicular to skin 1cm lateral to anterior border of tibia
• Deep Posterior Compartment: enter perpendicular to skin, just posterior to the medial border of tibia
• Superficial Posterior Compartment: enter middle of calf
• Lateral Compartment: enter just anterior to posterior border of fibula

Karadsheh, 2015

Treatment:
Non-operative:
1. Bi-Valve James' cast
2. Observe: if not consistent with compartment syndrome
3. Hyperbaric oxygen therapy: increases oxygen diffusion gradient

Operative: Emergent fasciotomy of all four compartments
Indications:

• Compartment pressures of 30-45mmHg
• Clinical presentation with compartment syndrome
• Compartment pressures within 30mmHg of diastolic BP

Procedure
1. Dual (2 incisions) medial and lateral incision: 2 x 15 cm incisions

Posteriormedial incision (Karadsheh, 2015)

Anteriorlateral incision (Karadsheh, 2015)

2. Single lateral incision from head of fibula to ankle along line of fibula

Karadsheh, 2015

REFERENCES
Karadsheh, M. 2015 Leg Compartment Syndrome. Orthobullets. Available from: http://www.orthobullets.com/trauma/1001/leg-compartment-syndrome. Accessed 10/7/15.

Klenerman L. The evolution of the compartment syndrome since 1948 as recorded in the JBJS (B). J Bone Joint Surg Br 2007; 89:1280.

Stracciolini, A., Hammerberg, E. 2014. Up To Date. Acute Compartment Syndrome available from: http://www.uptodate.com/contents/acute-compartment-syndrome-of-the-extremities#H8 Accessed 1/7/15