Fasciotomy is the definitive treatment for Acute compartment syndrome (ACS). When performed in time, it can prevent irreversible ischemic damage to muscles and nerves. The same principles apply to all affected limbs: identify the at-risk limb, act without delay, and completely release all involved compartments to prevent permanent neuromuscular injury.

Introduction

ACS is a limb-threatening condition caused by rising pressure within a closed muscle compartment. The non-compliant fascia surrounding these compartments means that any increase in volume (e.g. bleeding or edema) results in a rapid rise in intracompartmental pressure. Once this pressure exceeds capillary perfusion pressure, ischemia of muscles and nerves occurs.

Fasciotomy is the definitive treatment for ACS, and most clinicians are familiar with a fasciotomy of the lower leg, where the four compartments are decompressed. However, fasciotomy of the foot, thigh, forearm, and upper arm is less commonly taught and often poorly understood, despite the potentially devastating consequences of missed or incomplete release.

Early complications in open fractures

Incidence

ACS most commonly follows high-energy trauma. It may also occur after reperfusion (e.g. following vascular reconstruction or thrombolysis), crush injuries, prolonged limb compression (entrapment), ischemia, or burns. 

Fractures account for approximately 75% of cases, with the highest risk seen in tibial injuries¹, with the highest risk seen in tibial injuries (2–9% of all cases).

Fractures with a higher risk of ACS include:

• Supracondylar humeral fractures
• Segmental fractures
• Displaced forearm shaft fractures
• High-energy distal radius fractures
• Tibial apophyseal avulsions
• Tibial shaft fractures
• High-energy distal tibial fractures

However, ACS may also occur in the foot, thigh, and hand.

This guide provides an overview of the surgical techniques for decompression of the closed osteofascial compartments of the foot, lower leg, thigh, forearm, and upper arm.

General operative technique

1 Use a blade for the skin, and a cautery or blade for the subcutaneous fat. 

2 Incise the fascia with a small stab using the blade.

3 Use closed dissecting scissors under the fascia to push away muscle and other structures in both directions

4 Reinsert the scissors with an open beak and open the fascia along its full length by sliding/cutting through it, keeping the beak open and slightly lifted to avoid damage to underlying tissues.

5 Leave the fascia and overlying layers open to allow swelling.

Upper Arm Fasciotomy

Anatomy

The upper arm consists of two main compartments:

• Anterior compartment, containing the musculocutaneous, median, and ulnar nerves, the brachial artery and veins, and the biceps brachii, brachialis, and coracobrachialis muscles.
• Posterior compartment, containing the radial nerve, the profunda brachii artery and veins, and the triceps brachii (long, lateral, and medial heads).

Fig. 1. The two compartments of the upper arm: anterior and posterior.

Technique

1 Plan the incision
For a medial approach, also known as brachial fasciotomy: Mark an oblique medial incision from the medial epicondyle towards the axilla, approximately 15 to 20 centimetres in length. Identify and protect the ulnar nerve at the medial epicondyle before proceeding deeper.

Fig 2. Medial incision for upper arm fasciotomy

2 Open the anterior compartment (biceps)
Incise the fascia over the biceps and release it longitudinally along the full length of the compartment (see fig 3).

3 Open the posterior compartment (triceps)
Through the same medial incision, identify the medial intermuscular septum and divide it to decompress the posterior compartment (see fig 3).

Fig 3. Opening of the anterior compartment.

Optional posterior incision (triceps)
If the posterior compartment remains tense, make a longitudinal incision between the long and lateral heads of the triceps, extending from just inferior to the deltoid insertion towards the lateral epicondyle. Incise the triceps fascia to complete the posterior release. Take great care proximally, as the radial nerve crosses the posterior humerus and is at risk during deep dissection

Fig. 5-6. Optional direct posterior triceps release.

Forearm Fasciotomy

Anatomy

The forearm consists of three compartments:

• Volar compartment
  o  Superficial layer, containing the median nerve and ulnar nerve, and the muscles flexor carpi ulnaris, palmaris longus, and flexor digitorum superficialis.
  o  Deep layer, containing the anterior interosseous nerve, and the muscles flexor digitorum profundus, flexor pollicis longus, and pronator quadratus.
• Mobile wad, containing the superficial branch of the radial nerve, and the muscles brachioradialis, extensor carpi radialis longus, and extensor carpi radialis brevis.
• Dorsal compartment, containing the posterior interosseous nerve, and the muscles extensor digitorum communis, extensor digiti minimi, extensor carpi ulnaris, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, and extensor indicis.

Technique

1 Plan the incision
Start distally in the palm and mark the incision crossing both the carpal tunnel and Guyon’s canal. Curve towards the radial side at the mid-forearm, then continue proximally along the anterolateral aspect of the forearm (see Fig. 2). If needed, extend the incision proximally in line with the same anterolateral trajectory across the elbow.

The carpal tunnel must be formally released as part of the forearm fasciotomy. Fully release the transverse carpal ligament starting with a scalpel, followed by extension with scissors to ensure complete decompression.

Fig 7-8.  Anterior dermato-fasciotomy incision

2 Open the superficial volar compartment
Incise the skin along the marked line. Continue by opening the fascia with scissors to decompress the superficial volar compartment.

Fig 9. Opening of the superficial volar compartment.

3 Open the deep volar compartment
Retract the radial artery, the superficial branch of the radial nerve, and the brachioradialis laterally. Identify the pronator teres, which overlies the proximal radius. Develop the dissection along its ulnar border to access the deep volar compartment. Bluntly dissect down to the deep volar fascia, then incise it to decompress the deep volar compartment. 

Take care to identify and protect the median nerve, which lies in close proximity.

Fig. 10. Opening of the deep volar compartment.

4 Open the mobile wad
Through the same incision, retract the brachioradialis and the extensor carpi radialis longus and brevis laterally. Incise the fascia to decompress the mobile wad. Take care to protect the superficial branch of the radial nerve throughout the release.

5 Open the dorsal compartment
Mark and incise the skin over the dorsal forearm. Open the fascia with scissors and decompress the dorsal compartment in line with the incision.

Fig 11. Opening of the dorsal compartment.

Thigh fasciotomy

Anatomy

The thigh consists of three compartments, with muscular content varying proximally to distally:

Fig 12. The three compartments of the thigh at a mid femoral level.

Mid femur

• Anterior compartment, containing the femoral nerve and femoral vessels, and the sartorius, vastus medialis, rectus femoris, vastus intermedius, and vastus lateralis muscles.
• Medial compartment, containing the obturator nerve and profunda femoris vessels, and the adductor longus, adductor brevis, adductor magnus, and gracilis muscles.
• Posterior compartment, containing the sciatic nerve and profunda perforators, and the biceps femoris, semitendinosus, and semimembranosus muscles.

Fig 13. Mid-thigh compartments: a. anterior compartment. b. medial compartment. c. posterior compartment.

Technique

Two incisions are required to decompress all thigh compartments: a long lateral incision and a medial incision (See fig. 14).

1 Plan the incisions
Mark the lateral incision from the greater trochanter to the lateral femoral epicondyle, and mark the medial incision from the adductor tubercle proximally along the line of the adductor magnus tendon (see fig. 15).

Fig 15. Lateral (a) and medial (b) fasciotomy incisions for the thigh.

2 Lateral fasciotomy
Make a longitudinal incision from the greater trochanter to the lateral femoral epicondyle. Incise the fascia lata and iliotibial band along the full length of the wound, then split them to expose the vastus lateralis (see Fig. 6).

Fig 16. Incision of the skin and  fascia lata.

Gently elevate the fascia from the surface of the vastus lateralis and retract the muscle anteromedially (see Fig. 17 ). Incise the fascia over the vastus lateralis approximately 1 cm anterior to the lateral intermuscular septum to decompress the anterior compartment (see Fig. 18).

Fig 17. Separation of the fascia from the vastus lateralis
Fig 18. Incision of the fascia over the vastus lateralis

Elevate the vastus lateralis from the lateral intermuscular septum and the linea aspera (see Fig. 9). Identify the profunda perforators as they cross the septum, and ligate or coagulate them carefully to maintain haemostasis (see Fig. 19).

Fig 19. Elevating the vastus lateralis
Fig 20. Ligating perforators crossing the septum

Finally, split the lateral intermuscular septum longitudinally along the full length of the incision to decompress the posterior compartment (see Fig. 21).

Fig 21.  Decompression of posterior compartment

3 Medial fasciotomy

Make a longitudinal incision along the adductor magnus tendon, beginning at the adductor tubercle and extending proximally as required (see fig. 15) . Distally, identify the sartorius and vastus medialis, and protect the saphenous nerve and vein. Continue proximally to expose the vastus medialis and adductor magnus. At deeper levels, identify and protect the femoral artery and vein deep to the vastus medialis (see Fig. 22)

Fig 22.  Deep dissection, identifying a. the sartorius, vastus medialis, saphenous vein and nerve. b. femoral vein and artery.

More proximally, identify the rectus femoris, vastus medialis, adductor longus, and adductor magnus, while safeguarding the femoral neurovascular bundle throughout the dissection. Perform a complete longitudinal fascial release of the medial compartment and the fascia over the vastus medialis to decompress both the medial and anterior compartments.

Fig 23.  Decompression of the medial and anterior compartments

Ensure full-length fascial release, incomplete medial release risks persistent compartment pressure.

Lower leg Fasciotomy

Anatomy

The lower leg consists of four compartments:

• Anterior compartment, containing the deep peroneal (fibular) nerve, anterior tibial vessels, and muscles tibialis anterior, extensor hallucis longus, extensor digitorum longus, and peroneus tertius.
• Lateral compartment, containing the superficial peroneal (fibular) nerve and peroneus longus and brevis muscles.
• Superficial posterior compartment, containing the gastrocnemius, soleus, and plantaris muscles.
• Deep posterior compartment, containing the tibial nerve, posterior tibial and peroneal vessels, and muscles tibialis posterior, flexor digitorum longus, and flexor hallucis longus.

Fig. 24. The four compartments of the lower leg: anterior, lateral, superficial posterior, and deep posterior compartments.

Technique

1 Plan the incision
Mark two long fasciotomy incisions, approximately 15–20 cm in length. The anterolateral incision provides access to the anterior and lateral compartments. The posteromedial incision allows decompression of the superficial and deep posterior compartments.

Fig 25. Incision planning for lower leg fasciotomy.
Fig 26. Incision for lower leg fasciotomy.

2 Open the anterior and lateral compartments
Make an anterolateral incision approximately 2 cm anterior to the fibular shaft, beginning roughly 3 cm distal to the tibial crest and extending towards the lateral malleolus. Identify and release the anterior compartment fascia, then open the lateral compartment by dividing the anterior intermuscular septum.

Fig 27-28. Release of the anterior and lateral compartments through the anterolateral incision.

3 Open the superficial and deep posterior compartments
Make a posteromedial incision approximately 2 cm posterior to the medial tibial border, extending towards the medial malleolus. Release the superficial posterior compartment fascia. Identify the soleus bridge and incise it longitudinally to enter and decompress the deep posterior compartment. Take great care in the distal third of the incision, where perforating vessels from the posterior tibial artery are at risk.

Fig. 29. Release of the superficial and deep posterior compartments through the posteromedial incision.

Foot Fasciotomy

Anatomy

The foot consists of six compartments:

• Medial compartment, containing the medial plantar nerve and the abductor hallucis and flexor hallucis brevis muscles.
• Central compartment, containing the flexor digitorum brevis and flexor digitorum longus tendons.
• Lateral compartment, containing the lateral plantar nerve and the abductor digiti minimi and flexor digiti minimi brevis muscles.
• Adductor compartment, containing the adductor hallucis (oblique and transverse heads).
• Four interosseous compartments, dorsally located between the metatarsals, containing dorsal and plantar interossei.
• Calcaneal compartment, containing quadratus plantae and at risk in calcaneal fractures due to bleeding and compression of the plantar neurovascular bundles.

Fig. 30. Five of the six main compartments of the foot: medial, central (superficial), lateral, adductor (deep) and four interosseous compartments.

Technique

1 Open the interosseous and adductor compartments
Make dorsal incisions just medial to the second and lateral to the fourth metatarsal shafts. Open the fascia to decompress the interosseous compartments. 

In the first web space, release the adductor compartment deeply to ensure decompression.

Fig 31. Release of the interosseous and adductor compartments through dorsal incisions.

2 Open the medial and central compartments.
Make an incision along the abductor hallucis. Elevate the muscle to expose the medial compartment fascia and release it. Continue more deeply to decompress the central compartment in continuity.

Fig 32. Medial incision and release of the medial and central compartments.

3 Open the lateral compartment
Make a small incision plantar to the fifth metatarsal. Release the fascia over the abductor digiti minimi and the flexor digiti minimi brevis to decompress the lateral compartment.

Fig. 33. Release of the lateral compartment.

Aftercare

Postoperative splintage

Position the limb in a neutral functional posture to prevent contractures, particularly when muscle damage has occurred. Avoid circumferential splints or casts; use open splintage with elevation.

Delayed surgical closure

When swelling has subsided, the wound is clean, and skeletal stabilization is secure, proceed with delayed closure strategies. Only skin should be closed, deeper tissues/fascia should not be sutured/closed.

Options include:

• Progressive closure using elastic vessel loops through skin staples
• Negative-pressure wound therapy (VAC) to reduce edema and optimize wound bed
• SSG (split-thickness skin graft) for stable coverage when primary closure is not possible

Fig 34-35. Elastic vessel loops

Complete closure without grafting may be achievable once soft-tissue swelling resolves, particularly in pediatric patients. Secondary closure can be performed after graft-take if grafted initially.