First Metatarsal Fracture

Description

First metatarsal fractures deserve careful evaluation. The first ray is unique biomechanically and anatomically. The first metatarsal and its two associated sesamoids bear approximately one third of the body weight. The first metatarsal also has unique anatomic relationships with the medial cuneiform, and this articulation is important to the stability of the transverse arch. For all these reasons, it is important to restore the length and stability of the first metatarsal anatomically in both the transverse and sagittal planes.

Anatomy

There is a complex relationship between the first metatarsal head and the sesamoid complex including the adductor hallicus and intermetatarsal ligaments. The ligamentous complex of the tarsal metatarsal articulations is composed of dorsal, plantar and interossoeus components. However the first and second metatarsal bases lack an interosseous ligament. There is very little inherent motion in the first TMT articulation whereas the first MTP joint has an arc of motion of approximately forty degrees of plantarflexion and need to put something in here degrees of dorsiflexion. The first metatarsal in addition to the joint complexes has attachments of the tibialis anterior tendon and peroneus longus which can also act as deforming forces. There is a relatively small soft tissue envelope around the first MT especially when compared to the lesser metatarsals.

In summary, the first ray supports approximately one third of the weight of the foot. The first metatarsal is integral in the relationships of the first metatarsal phalangeal and tarsal metatarsal joints. In addition to these two articulations, the metatarsals are all connected by the deep transverse intermetatarsal ligaments. Displaced fractures of the first metatarsal may lead to biomechanical alterations of the entire forefoot and tarsal metatarsal articulations.

Causes

First metatarsal fractures result from a variety of low and high energy mechanisms. Low energy mechanisms include a stress response, and low energy injuries such as a twisting moment arm on the forefoot. High energy trauma includes lawn mower injuries, industrial accidents, and motor vehicle accidents.

Symptoms

First Metatarsal fractures arise in patients of all ages. Most injuries are closed but the high energy and lawn mower injuries can present with open fractures. Typically, in low energy mechanisms, there is dorsal soft tissue swelling and ecchymosis and pain with weightbearing. When patients present with high energy mechanisms, the examiner should pay close attention to the neurovascular exam and both the TMT and MTP articulations.

Treatment

If the fracture is non- or minimally displaced, closed treatment is sufficient. Fractures involving the shaft and metatarsal neck are more commonly stable. Conservative treatment typically consists of short leg cast or CAM walker with limited weight bearing for 4-6 weeks. If there is any displacement, shortening, or angulation, operative intervention is indicated. Techniques include lag screw placement of longer oblique fractures and plate fixation. If the metatarsal fracture has significant comminution, particularly the first MT base, may require bridge plating fixation or spanning external fixation with a uni-rail fixator across the TMT articulation.

Written by Julie Johnson, MD Reviewed by Troy Watson, MD Last reviewed June 2015

Fifth Metatarsal Base Fracture

Description

Base of the fifth metatarsal fractures are those occurring between the tuberosity and proximal diaphysis. The fracture patterns observed here reflect the local anatomy and biomechanics. Three groups of fractures can be arranged based on their location, injury mechanism, and timing of injury. Treatment considerations include clinical and radiographic factors.

Anatomy

The base of the fifth metatarsal is comprised from proximal to distal by the tuberosity, metaphysis, and proximal diaphysis. The tuberosity is largely covered by the peroneus brevis tendon insertion but also features a plantar process for the insertion of the lateral band of the plantar aponeurosis and a facet for articulation with the cuboid. The metaphysis is distal to the tuberosity and is bound to the proximal fourth metatarsal metaphysis through relatively strong dorsal and plantar intermetatarsal ligaments. The metaphysis also features a medial facet for articulation with the fourth metatarsal. The proximal diaphysis extends 1.5 cm distal to the metaphysis. Whereas ample blood flow reaches the tuberosity (through abundant) metaphyseal-epiphyseal vessels) and prosimal diaphysis (through nutrient artery system), a relatively hypovascular zone exists between these systems in the region of the metaphysis.

Relatively strong dorsal and plantar intermetatarsal ligaments stabilize the articulation between the proximal fourth and fifth metatarsals. This complex resists displacement by tensile forces acting through the attachments on the tuberosity and by axial, rotational, and adduction forces acting through the diaphysis.

Causes

Fractures occur within three distinct zones of the base of the fifth metatarsal.

• Zone 1: Tuberosity avulsion fractures result from forces exerted through the peroneus brevis tendon and lateral cord of the plantar fascia. These fractures may extend into the fifth metatarsocuboid joint. Most commonly acute fracture.
• Zone 2: Acute Jones fractures were first correctly described by Sir Robert Jones in 1902 and extend from the distal tuberosity into the articulation with the fourth metatarsal. Rapid loading of the lateral foot with a relative adduction of the distal 5th MT produces acute fractures within or at the distal margin of the intermetatarsal ligament complex. Most commonly acute fracture.
• Zone 3: Diaphyseal stress fractures occur distal to the intermetatarsal ligaments and may extend distally 1.5cm into the tubular portion of the bone. These fractures result from repetitive loading with axial, rotational, and adduction forces acting through the diaphysis at sub-failure loads. These forces are resisted by the proximal intermetatarsal ligament complex resulting in stress concentration in the proximal diaphysis. Most commonly stress fractures occurring as a continuum from stress response without fracture to fracture nonunion.

Symptoms

Patients with acute fractures report an event with rapid loading on the lateral border of the midfoot causing the sudden onset of pain and swelling localized to the proximal fifth metatarsal. This may now limit their ability to bear weight. In contrast, patients with acute on chronic fractures, particularly of Zones 2 and 3, often report prodromal weight bearing associated pain along the lateral border of the midfoot with an acute increase in pain corresponding to the development of the fracture.

Treatment

Non-Surgical Treatment: Zone 1 fractures tend to heal well. Initial symptomatic care consists of rest, ice, elevation, oral NSAIDs. Weight bearing to tolerance is permitted in a hard-sole shoe or short leg walking cast for four to six weeks. Pain resolution precedes radiographic healing. Zone 2 and 3 fractures are at increased risk of delayed or nonunion. In addition to initial symptomatic care, nonoperative management consists of nonweight bearing in a short leg cast or cast boot for 6 to 8 weeks.

Surgical Treatment: Open reduction and internal fixation with a compression screw is reserved for intraarticular displacement involving the metatarsocuboid joint or displaced, malrotated proximal fracture fragments. Open reduction and internal fixation with an intramedullary compression screw and possibly bone grafting is an option for patients with inadequate radiographic signs of healing after 6 weeks or for those patients who wish to expedite return to physical activity. Surgery is typically recommended in elite athletes who present with this fracture.

Written by Christopher Reb, DO
  

Fifth Metatarsal Fracture

Description

The fifth metatarsal is the most common metatarsal fractured. The metatarsals are the most important weight bearing structure in the forefoot. Complex relationships between the metatarsals exist, and they work in conjunction, for ideal biomechanical foot function. The fifth metatarsal has a unique blood supply and biomechanical function that lend it to more complex considerations for fracture management than the other lesser metatarsals.

Anatomy

The fifth metatarsal has less soft tissue coverage and intrinsic muscle attachments than the lesser metatarsals. It has an important function in maintaining the tripod effect of the foot with the calcaneus and first metatarsal. The fifth metatarsal is the most mobile of the metatarsals. It has extrinsic muscle attachments including the peroneus brevis, tertius, and lateral band of plantar fascia. The blood supply of the fifth metatarsal is an important determinant in treatment algorithms. The fifth metatarsal is supplied by arterial branches from the dorsalis pedis, posterior tibial and peroneal arteries. The nutrient artery arises from the fourth plantar metatarsal artery and inserts into the plantar medial diaphysis of the metatarsal in approximately 80% of individuals. The metadiaphyseal region of the fifth metatarsal is vulnerable to increased nonunion rates due to the anatomic location of the bloody supply which results in this watershed zone.

Causes

Fifth metatarsal fractures result from a variety of low and high energy mechanisms. Low energy mechanisms include a stress response, and twisting injuries of the forefoot. High energy trauma includes lawn mower injuries, industrial accidents, and motor vehicle accidents. There are 2 eponyms that are commonly used to describe fifth metatarsal fractures: dancers and Jones fractures.

• Dancer’s fractures typically occur with inversion injuries and involve the shaft of the metatarsal. Fractures in this location typically heal well treated non-operatively.
• Jones fractures are the subject of much debate and there is sometimes confusion as to what anatomic location this refers to in the metatarsal. Fractures in the region of the meta-diaphyseal region are referred to Jones fractures; this is a relatively avascular zone which increases the rates of nonunion. Stress fractures more commonly occur in this metadiaphyseal region as well. Metatarsal base fractures typically occur in the cancellous region of the MT base, and likely occur due to an inversion strain of the lateral plantar aponeurosis. Metatarsal base fractures, when minimally displaced, heal well treated non-operatively.

Symptoms

Patients presenting with stress related injuries, typically describe a prodrome of pain that has been present from weeks to months prior to either fracture completion or presentation to the clinician’s office. Other common injury presentations include a forced abduction force of the forefoot with ankle planarflexion. Many acute Jones’ fractures occur in athletes. This has important implications in treatment and length of immobilization.

Classification

There is not a formal classification system for metatarsal head, neck and shaft fractures. These fracture locations tend to heal well with conservative treatments. There is a zone classification of proximal metatarsal fractures.

• Zone 1 involves the fifth metatarsal tuberosity.
• Zone 2 involves the proximal metaphyseal-diaphyseal junction without distal extension beyond the fourth and fifth intermetatarsal articulation or the acute Jones fractures.
• Zone 3 described diaphyseal fractures or the classic “dancer’s fractures”.

Treatment

For most metatarsal head, neck and shaft fractures, conservative treatment is the treatment of choice. Typically non-operative treatment in a cast or CAM boot for 6 weeks is indicated. These fractures take longer to heal radiographically, but as long as there is progression of healing and minimal pain it is common to advance the patient into a regular shoe at the 6 week mark from the injury. Non operative treatment in a cast, with non weightbearing status for 6-8 weeks and then transition into a CAM boot is recommended. If there is persistent pain after at least 3 months of conservative treatment operative intervention is considered.

Surgical Treatment: Surgery is indicated for non-unions and significant fracture displacement but is uncommon in this anatomic location. Almost all avulsion tuberosity fractures heal well treated non-operatively in a cast or CAM boot with weight bearing as tolerated for 8 weeks. For acute Jones fractures the treatment of choice is still non-operative unless there is a stress fracture prodrome and injury occurs in an elite athlete. Operative intervention in the form of an intramedullary solid screw is the treatment of choice. For fractures with a prodrome and stress response changes radiographically, most surgeons advocate for operative intervention. There is some debate whether to open the fracture site and bone graft for acute stress injuries. Many surgeons feel that reaming the fracture site with a drill is enough to stimulate union, in addition to placement of the intramedually screw. Finally, in elite athletes who wish to avoid the prolonged immobilization with conservative treatment, operative intervention is often the treatment of choice.

Written by Julie Johnson, MD Reviewed by Lawrence Berson, MD Last reviewed June 2015

Talus Fracture

Description

The talus is the most proximal bone in the hindfoot and is the link between the leg and the foot. It is a key component to normal ambulation and therefore a poor outcome after a talus fracture can be detrimental to the quality of life. Fractures of the talus are rare injuries and typically occur from high-energy trauma.

Anatomy

The talus is a unique bone in that 60% of it is covered in cartilage and there are no muscular attachments. The talus is divided into distinct anatomic regions, mainly the body, neck, and head. The vascular supply to the talus is tenuous and often disrupted in cases of talar neck fractures.

Symptoms

Patients typically present after a traumatic accident including a motor vehicle collision or a fall from a great height. The main complaint is exquisite pain in the involved ankle and hindfoot. Observation will demonstrate swelling and bruising about the hindfoot.

Treatment

Any associated joint dislocation should undergo emergent reduction in either the emergency room or operating room followed by open reduction and internal fixation based on the quality of the surrounding soft tissues and the comfort level of the surgeon. A peritalar dislocation that is reduced in the emergency room should be placed in a splint. A peritalar dislocation reduced in the operating room can either be placed in a temporary external fixator or placed in a splint. Assuming no dislocation, the patient is placed in a splint until a definitive treatment plan is obtained. Operative treatment is dictated by displacement. Truly non displaced fractures can be treated in a cast after swelling subsides.

In general, if there is any displacement, open reduction and internal fixation (ORIF) should be performed. Traditionally, with talar neck fractures, it was thought that emergent ORIF should be performed. However, more recent studies do not show a correlation with timing of surgery and the development of avascular necrosis of the talus. ORIF is performed with either screws or a plate(s) and screws depending on the fracture pattern. A medial incision, lateral incision or multiple incisions may be needed to gain access to the fracture. After surgery, the patient is placed in a splint/cast for 6 weeks and remains nonweightbearing. Depending on fracture stability and strength of fixation, weight bearing in a boot brace can begin once there are signs of healing.

Written by Samuel Adams, MD Reviewed by Steven Neufeld, MD Last reviewed June 2015

Tibial Plafond

Description

Fractures of the distal tibial weight-bearing surface, or the tibial plafond, are among the most difficult injuries the orthopaedic surgeon will treat. Fortunately, they are relatively rare, accounting for less than 10% of lower extremity fractures. They tend to occur in young (35-40 year-old) men, and cause significant morbidity.

Anatomy

The ankle mortise is made up of the articulations of the talus, the distal tibia, and the distal fibula. The tibial plafond (French for “ceiling”) forms the superior surface of the joint. The articular surfaces of the tibial plafond and talar body are covered with a layer of hyaline cartilage, which is thinner than the cartilage in either the knee or the hip. The bony and cartilaginous injury that can occur with tibial plafond fractures ultimately dictate the future function of the joint. The soft tissue envelope surrounding the tibial plafond and ankle joint is relatively thin, particularly over the medial surface of the distal tibia. As a result, tibial plafond fractures are often open injuries with full-thickness defects through the medial soft tissues. The distal neurovascular structures and tendons course very close to the surface of the distal tibial, and can also be at risk with tibial plafond fractures.

Causes

These injuries are often the result of a violent mechanism, such as motor vehicle collisions (MVCs), or falls from height.

Symptoms

Patients typically present to the emergency department after significant trauma, motor vehicle collisions, industrial accidents, or falls from height. The patient is typically in his 30’s or 40’s and may be in significant distress. They may complain of other musculoskeletal pain, and there may be other serious abdominal, thoracic or head injury. Other patients may present with a lower energy mechanism, such as a skiing accident, football or soccer injury, or bicycle crash.

Classification

The classification systems for tibial plafond fractures typically used include the Ruedi and Allgower, and AO systems.

• Type 1 fractures that are non-displaced
• Type 2 fractures with articular displacement
• Type 3 fractures that have articular comminution and impaction

The AO system is much more detailed, but basically has A-type fractures that are extra-articular, B-type fractures that have partial articular involvement, and C-type fracture that have complete articular involvement.

Treatment

In the initial treatment of tibial plafond fractures care of the soft tissue envelope frequently takes precedence over the bony injury. Open fractures should be debrided urgently and patients should be given IV antibiotics and tetanus boosters (as indicated) immediately. High energy injuries with significant displacement and shortening tend to have rapid swelling, and possible development of fracture blisters. Emergent fasciotomies must be performed on any patient with impending compartment syndrome.

Patients with truly non-displaced fractures, or patients with absolute contraindications for surgical treatment may be treated with immobilization and progressive mobilization and weight bearing as healing occurs.

The majority of patients with tibial plafond fractures will be best treated with surgical fixation. There is some debate regarding the optimal treatment protocols, including timing of surgery, and internal or external fixation. Some surgeons advocate definitive external fixation for some fractures. However, in general, internal fixation has the advantage of correction of the deformity and stabilization to allow for early range of motion. Fractures with severe soft tissue injury will typically best be treated with temporary spanning external fixator placement across the ankle to allow for restoration of the limb length, gross alignment, and stability. If performed appropriately the soft tissue envelope should heal and tolerate definitive open reduction and internal fixation by two to three weeks. The tenets of treatment of these fractures advocated by Ruedi and Allgower suggest a four-part approach. This starts with restoration of the appropriate fibular length, reconstruction of the articular surface of the plafond, bone grafting metaphyseal defects, and stable internal fixation. The fracture pattern and the associated soft tissue injury will tend to dictate the timing of surgery, surgical approach, and type of internal fixation. Typical approaches for fixation include anterolateral, anteromedial, posterolateral, and posteromedial. Some advocate direct anterior for some fracture patterns. Direct medial incisions should be used with great caution in treating these fractures due to the very thin soft tissue envelope overlying this area of the distal tibia. Post-operative care will usually require a brief period of splint the ankle until soft tissues have healed sufficiently to allow for early motion at the ankle and subtalar joints. Weight bearing is typically restricted to non-weight bearing for 12 weeks post-operative depending on the amount of articular involvement, and a removable splint or boot should be used to prevent equinus contracture.

Written by J.P. Elton, MD

Calcaneous

Description

The calcaneus is the largest of the tarsal bones of the foot. It articulates with the talus through the posterior, middle, and anterior facets. The largest and most critical of these articulations is the posterior facet. The articulation between the talus and calcaneus also form the sinus tarsi. The calcaneus also articulates with cuboid forming calcaneal-cuboid joint. The Achilles tendon inserts on the calcaneal tuberosity along the posterior portion of calcaneus. The sustentaculum tali is a projection along medial aspect of calcaneus. It has numerous ligaments insertions and the Flexor Hallucis Longus tendon passes beneath it. Due to its strong ligament attachments it frequently does not displace during fracture and is commonly referred to as the “constant fragment”

The calcaneus is critical to hindfoot function. It plays major role in hindfoot motion. It functions with the talus to provide inversion and eversion. The position of hindfoot is also thought to effect transverse tarsal locking mechanism with a varus position locking and stabilizing midfoot for propulsion. When the hindfoot is everted the transverse tarsal joints are supple and function to accommodate uneven ground. The calcaneus also provides lever arm for plantar flexion and is a strong foundation for bearing weight.

Causes

Calcaneal fractures typically present after significant axial load (fall from ladder) or after motor vehicle accident. The talus is impacted, specifically the by lateral process, into the calcaneus creating a impaction type fracture. This typically creates common pattern seen with primary fracture line extending from anterior lateral to posterior medial. Secondary fracture lines are also frequently seen extending out through the tuberosity. This frequently lead to articular incongruity, a widen heel with varus angulation, and loss of calcaneal height. Avulsion fractures of the tubersoity are also seen and frequently occur following eccentric load on the Achilles tendon.

Types of Calcaneal Fractures

There are numerous classifications for calcaneal fractures. A pre-operative CT classification was developed by Sanders and is commonly used when classifying calcaneal fractures. This classification specifically focuses on coronal CT assessment of posterior facet. It assists the surgeon with surgical planning and it is based on number and location of fracture lines involving the posterior facet.

• Type 1 are non-displaced fractures
• Type 2 have one fracture line involving the posterior facet
• Type 3 have two fracture lines involving the posterior facet
• Type 4 have three or more posterior facet fracture lines.

The fracture lines of type 2, 3, and 4 are further classified by location medial to lateral involving posterior facet with A being lateral, B being middle, and C being medial. This classification has also been shown to have prognostic value.

Symptoms

These injuries commonly present after significant fall from height or high-energy motor vehicle accidents. Calcaneal fractures frequently demonstrate a significantly swollen widened heel with varus angulation. Patients may have severe pain with an inability to weight bear on the effected side. Attention should be paid to evaluation of posterior skin if tuberosity avulsion is noted.

Treatment

Open fractures require surgical debridement.Closed fracture treatment depends on a number of factors. Smoking, advanced age, and occupation as a laborer are all factors associated with poor outcomes following surgical stabilization.

Non-surgical Treatment:

When non-operative treatment is selected, patients are typically immobilized between 6 and 12 weeks depending on severity of fracture. After immobilization patients are returned to weight bearing slowly, advised to focus on range of motion exercises, and likely benefit from physical therapy, shoe modification, and custom orthosis.

Surgical Treatment

Fractures involving an avulsion of achilles insertion with pressure on posterior skin require immediate stabilization to prevent skin necrosis. Operative management of tongue type and tuberosity avulsion fractures can frequently be fixed with screws minimally invasive incisions.

Displaced intra-articular fractures can be treated with open reduction internal fixation with extended lateral approach or minimally invasive sinus tarsi approach depending on fracture severity and surgeon comfort.

Occasionally in severe comminuted fractures, reduction and primary arthrodesis may be indicated but to this date no difference in outcomes has been established. Operative management should not be performed until soft tissue swelling has resolved and skin wrinkles are noted.

References

1. Macey LR, Benirschke SK, Sangeorzen BJ, and Hansen Jr ST. Acute Calcaneal Fractures: Treatment Options and Results. J Am Acad Orthop Surg 1994;2:36-43
2. Essex-Lopresti P, The Mechanism, Reduction Technique, and Results in Fractures of Os Calcis. Br J Surg. 1952;3:395-419
3. Buckley R, Tough S, McCormack R, Pate G, Leighton R, Petrie D, Galpin R. Operative Treatment of Displaced Intra-articular Calcaneal Fractures: A Prospective Randomized Controlled Multicenter Trial. JBJS AM. 2002; 84:1733-1744
4. Sanders R: Intra-articular Fractures of the Calcaneus: Present State of the Art. J of Orthopedic Trauma. 1992; 6: 252-265
5. Buckley R, Leighton R, Sanders D, Poon J, Coles CP, Stephen D, Paolucci EO. Open reduction and internal fixation compared with ORIF and primary subtalar arthrodesis for treatment of Sanders type IV calcaneal fractures: a randomized multicenter trial. J Orthop Trauma. 2014 Oct;28(10):577-83.