Lower Extremity Fasciotomies

Introduction

Acute compartment syndrome (ACS) of an extremity occurs when significant pressure builds up within a closed osteofascial space, which can result in irreversible damage to structures contained within the specific compartment.

Fractures are the most common cause of compartment syndrome, but ischemia-reperfusion (after vascular injury), burns, prolonged immobilization, and crush injuries can also result in ACS. Diagnosing ACS early is critical in appropriately treating and reducing the risk of associated complications.

While pain out of proportion to injury is the classic finding associated with ACS, early findings include paresthesias and pain on passive muscle stretch and late findings include loss of pulses or motor deficits. Although diagnosis is primarily clinical, intracompartmental pressures can be measured when findings are equivocal.

30 mmHg is often the threshold for fasciotomy. Once a diagnosis of ACS is suspected or confirmed, emergent fasciotomies need to be performed to relieve the compartmental pressure.

Anatomy

Buttock:

• Gluteus maximus compartment
  Inferior gluteal nerve and blood supply from the superior and inferior gluteal arteries
• Gluteus medius compartment
  Superior gluteal nerve and blood supply from the superior gluteal artery
• Gluteus minimus compartment
  Superior gluteal nerve and blood supply from the superior gluteal artery

Thigh:

• Anterior compartment
  Muscles: Sartorius, quadriceps, articularis genus
  Neurovascular: Femoral nerve and vessels
• Medial compartment
  Muscles: Pectineus, external obturator, gracilis, adductor longus, adductor brevis, adductor minimus, adductor magnus
  Neurovascular: Obturator nerve and vessels
• Posterior compartment
  Muscles: Biceps femoris, semitendinosus, semimembranosus
  Neurovascular: Sciatic nerve and deep femoral vessels

Lower Leg:

• Anterior compartment
  Muscles: Tibilalis anterior, extensor hallucis longus, extensor digitorum longus, peroneus tertius
  Neurovascular: Deep peroneal nerve, anterior tibial vessels
• Lateral compartment
  Muscles: Peroneus longus, peroneus brevis
  Neurovascular: Superficial peroneal nerve
• Superficial posterior compartment
  Muscles: Gastrocnemius, soleus, plantaris
  Neurovascular: Sural
• Deep posterior compartment
  Muscles: Tibialis posterior, flexor hallucis longus, flexor digitorum longus, popliteus
  Neurovascular: Tibial nerve, posterior tibial and peroneal vessels

Foot:

Although there is controversy regarding the number of compartments in the foot, we describe the 5 commonly acknowledged compartments. Importantly, care must be taken to avoid injury to the neurovascular bundles that run medially and laterally.

• Medial compartment
  Abductor hallucis, flexor hallucis brevis
• Lateral compartment
  Abductor digiti quinti, flexor digiti minimi
• Superficial compartment
  Flexor digitorum brevis, lumbricals
• Calcaneal compartment
  Adductor hallucis, quadratus plantae, flexor digitorum brevis
• Interosseous compartment
  Interosseus muscles

Indications/Contraindications

Primary indications for fasciotomy of the lower extremity are compartment syndrome and symptoms related to ACS:

• Pain out of proportion to exam findings/injury or pain on passive stretch
• Paresthesias
• Pallor
• Poikilothermia
• Pulselessness
• Paralysis

However, assessing for these symptoms may be challenging in unconscious or obtunded patients. As such, compartment pressures can be monitored to assist in diagnosis. These can be checked with a needle manometer (e.g. Stryker device) or some form of catheter-transducer technique. An intra-compartmental pressure >30mmHg in a normotensive patient or >20mmHg in a hypotensive patient are generally used as the thresholds for diagnosing ACS.

While there are no absolute contraindications to performing a fasciotomy, the risks and benefits of performing a fasciotomy for a delayed presentation (>12 hours) should be carefully weighed on a patient-to-patient basis. Delayed fasciotomies have shown to have higher rates of infection, rates of amputation, and mortality as these patients present later in the disease process when irreversible damage has already occurred.

Equipment

The following equipment should be obtained before the start of the procedure, and it should, ideally, be performed in a sterile fashion.

• Antiseptic solution
• Drapes, towels, and gauze
• Skin scalpel
• Electrocautery
• Forceps
• Hand-held retractor
• Scissors

Preparation

The procedure can be conducted in an operating room or at the patient bedside. Ensure that all the personnel and equipment necessary for the procedure are ready and available. Make sure that the patient is properly sedated and additional anesthetic/analgesic medications are available in the room. The patient should be appropriately positioned (prone for buttock compartments and supine for thigh, lower leg, and foot compartments) with the leg propped up with a bump, if necessary. Before the start of the procedure, perform a World Health Organization safe surgical checklist to confirm the correct patient and location.

Steps

Various techniques have been described for fasciotomies of the lower extremities, but the core aspect of all is adequate release of the fascial compartments.

Buttock:

An incision should be made extending from the medial third of the iliac crest, posteriorly, down to the intertrochanteric line in a curvilinear fashion. Fascia overlying all three gluteal muscular compartments should then be incised, longitudinal to the muscle fibers.

Thigh:

• An incision should be made on the lateral aspect of the thigh extending from the intertrochanteric line down to the lateral epicondyle of the femur
• The iliotibial band should be incised length-wise down the entire incision
• A fascial incision can be made on the vastus lateralis releasing the anterior compartment
• Then the vastus lateralis should be medially retracted, and a separate fascial incision made along the intermuscular septum

Compartment syndrome of the medial compartment of the thigh is a rare entity, but if suspected, a separate skin incision should be made on the medial aspect of the thigh from the proximal 1/3 of the thigh down to the medial epicondyle of the femur. This can then be brought down to the adductor muscles by releasing the overlying fascia. Care should be taken to avoid injury to the great saphenous vein.

Lower Leg:

Medial skin incision:

• A skin incision 1cm medial to the tibial margin extending from the proximal 1/3 to a few cm above the medial malleolus
• Taking care to avoid injury to the saphenous nerve and vein, dissect down to the fascia overlying the gastrocnemius muscle
• Incise this fascia lengthwise to release the superficial posterior compartment
• The deep posterior compartment can be released by separating the soleus muscle from the tibia through this incision

Lateral skin incision:

• An incision can be made in between the tibial crest and fibula, extending similarly to the medial incision
• Dissection should continue down to the muscular fascia with subsequent identification of the intermuscular septum, which separates the anterior and lateral compartments
• A large subcutaneous flap should be made anteriorly to the tibia to avoid missing the anterior compartment and a 2 cm transverse incision should be made overlying the prospective septum between the anterior and lateral compartments to confirm each.
• Both of these compartments should be then released with separate longitudinal  incisions
• To avoid injury to the peroneal nerve branches, keep the proximal extent of fascial incisions 5cm distal to the fibular head

Foot:

• Two separate incisions should be made overlying the lengths of the 2^nd and 4^th metatarsal bones
• Dissection can then be carried down to the bone with subsequent release of all interosseus compartments by extension down both medial to and lateral to these metatarsal bones
• Extension of the medial aspect of the medial incision to below the 1^st metatarsal will allow for release of the medial compartment
• Similarly, extension of the lateral aspect of the lateral incision to below the 5^th metatarsal will allow for release of the lateral compartment
• Finally, the calcaneal compartment, which lies underneath the metatarsals, can then be released directly

After release of the appropriate compartments and hemostasis is achieved, the incisions can be left open for a second look 24-48 hours post-procedure. Wet-to-dry gauze or wound vacuum dressing can be used to cover the wounds. Closure of the wounds can be done by simple approximation of the subcutaneous tissue and skin. Edema might make approximation difficult, in which case, closure can be performed in a delayed/staged fashion. Occasionally, skin grafts may need to be utilized to close the wounds.

Complications

Complications from fasciotomy often times result from the underlying condition that resulted in compartment syndrome. In addition to direct complications from compartment syndrome, which can include paralysis, other potential complications include muscle necrosis, rhabdomyolysis, renal failure, and death.

Additionally, technical complications from fasciotomy can occur:

• Incomplete fasciotomy – can be due to distortion of tissue from edema and inflammation or from traumatic injury
• Vessel or nerve injury
• Wound – infection, need for skin grafting

Summary

• Compartment syndrome occurs after an insult, resulting in elevation of intrafascial pressures that can lead to irreversible damage of associated structures
• Depending on the mechanism of injury, compartments of the associated lower extremity region(s) should be closely monitored for development of compartment syndrome
• Compartment pressures should be checked when exam findings are equivocal or in obtunded patients
• If compartment syndrome is suspected or confirmed, fasciotomies should be emergently performed
• Care must be taken to ensure that all compartments of the affected region are released to avoid incomplete fasciotomies
  • Generous subcutaneous flaps should be made if necessary to assure opening of all appropriate compartments (e.g. a large subcutaneous flap should be made anterior to the tibia to avoid missing the anterior compartment)
  • When incising an intermuscular septum between compartments, confirm adequate release of both compartments with a transverse incision (e.g. a 2cm transverse incision should be made overlying the septum between the anterior and lateral compartments of the lower leg to confirm each)
  • Missed compartment syndrome can be a dilemma as opening this space can result in a high risk of deep tissue infection and resulting sequelae; on the other hand, it is difficult to know if partial salvage is possible without surgery
  • Care for these patients should be tailored after weighing the risks and benefits based on injury, timing, overall trauma burden, and other associated comorbidities

References

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3. Ritenour AE, Dorlac WC, Fang R, Woods T, Jenkins DH, Flaherty SF, Wade CE, Holcomb JB. Complications after fasciotomy revision and delayed compartment release in combat patients. J Trauma. 2008 Feb;64(2 Suppl):S153-61; discussion S161-2. doi: 10.1097/TA.0b013e3181607750. PMID: 18376159.
4. Tillinghast CM, Gary JL. Compartment Syndrome of the Lower Extremity. 2019 Sep 3. In: Mauffrey C, Hak DJ, Martin III MP, editors. Compartment Syndrome: A Guide to Diagnosis and Management [Internet]. Cham (CH): Springer; 2019. Chapter 8. Available from: https://www.ncbi.nlm.nih.gov/books/NBK553915/ doi: 10.1007/978-3-030-22331-1_8
5. Torlincasi AM, Lopez RA, Waseem M. Acute Compartment Syndrome. [Updated 2022 Jan 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK448124/.
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