Proximal tibial fractures in adults

INTRODUCTION — Tibial fractures are common among long-bone fractures. Proximal tibia fractures often involve the knee joint and so require careful evaluation, and often surgical referral.  

The presentation, evaluation, and non-surgical management of proximal tibial fractures in adults are reviewed here. A general overview of tibial fractures and the presentation and evaluation of other types of tibial fractures are discussed separately. (See "Overview of tibial fractures in adults" and "Overview of tibial fractures in children" and "Tibial shaft fractures in adults" and "Stress fractures of the tibia and fibula".)

EPIDEMIOLOGY — In a single year in the United States, greater than 70,000 hospitalizations, 800,000 office visits, and 500,000 hospital days have been attributed to tibial fractures. Data suggest that proximal tibia fractures are more common than those in the midshaft or distal regions. From 2011 to 2015, the Swedish Fracture Registry documented 1371 tibia fractures, of which 712 were proximal [1]. In a Danish cohort study of 60,823 patients with knee fractures sustained over 20 years, the incidence of proximal tibial fractures increased significantly during the study period [2]. Groups at highest risk were females older than 51 years and patients with comorbidities.

Fractures of the proximal tibia are more often due to high-energy trauma, such as motor vehicle collisions, compared with distal fractures. Older adults are at higher risk for tibial fractures caused by low-energy trauma, such as a fall; the presence of significant osteoporosis increases the risk for compound or more complex fractures with higher morbidity [3]. (See "Overview of tibial fractures in adults", section on 'Epidemiology'.)

CLINICAL ANATOMY — The tibia is the major weight-bearing bone of the lower leg (figure 1 and figure 2). The proximal portion of the bone, the tibial plateau, forms the lower surface of the knee joint (figure 3). The thicker of the two articular surfaces is the medial tibial condyle, while the lateral tibial condyle is a relatively thinner and weaker portion of the joint. The anatomy of the knee is reviewed in detail separately. (See "Physical examination of the knee", section on 'Anatomy'.)

Separating the medial from the lateral tibial condyle is the intercondylar eminence, an important bony prominence that anchors the attachment of the anterior cruciate ligament (ACL) (picture 1 and figure 4).

Another key bony landmark is the tibial tuberosity which is on the anterior surface, several centimeters below the joint line and the inferior patellar pole (picture 2), which serves as the attachment site for the patellar tendon (picture 3 and figure 4) [4].

A strong fibrous structure, the interosseous membrane, connects the tibia and fibula along the length of the two bones (figure 5). Proximally, this structure, reinforced by strong anterior and posterior ligaments, forms a synovial joint, the proximal tibiofibular articulation.

Another fibrous structure, the crural fascia, surrounds the bones and muscles of the lower leg. Fascial extensions and the interosseous membrane separate the muscles, nerves and vessels of the lower leg into four distinct compartments (figure 6). Three of these, the anterior, posterior, and deep posterior compartments all border the tibia and can be compromised by tibial injury.

Nerves and vessels lie within the anterior and the deep posterior compartments and trauma that causes significant swelling in these compartments can result in neurovascular compromise. The key blood supply of the tibia arises from periosteal vessels and the nutrient artery. The nutrient artery originates from the posterior tibial artery and enters the posterolateral cortex at the middle third of the tibial shaft near the origin of the soleus muscle (figure 7). Fractures in this region potentially compromise this blood supply.

The periosteal vessels provide a less vulnerable circulation as they derive an abundant blood supply from the anterior tibial artery which travels down along the interosseous membrane. Vascular compromise can arise more proximally from marked effusion of the knee joint or trauma that affects the popliteal artery before it branches into the anterior and posterior tibial arteries or at the level of the anterior tibial artery as it branches off the popliteal artery and passes through a gap in the interosseous membrane [4].

The tibial nerve and several branches provide the key innervation to the muscles of the lower leg and foot (figure 8). Nerve roots arise from L4 through S3. The posterior tibial nerve parallels the course of the posterior tibial artery and courses through the deep posterior compartment. In the popliteal space branches of the tibial nerve provide innervation to the posterior compartment and to the popliteus muscle. The deep peroneal nerve branches and follows the course of the anterior tibial artery providing innervation to muscles in the anterior lower leg.

MECHANISM OF INJURY — Significant direct trauma, knee hyperextension injuries, and twisting motions in older adults and other osteoporotic individuals are among the most common ways that proximal tibial fractures occur. In adults, vehicle-pedestrian collisions, motor vehicle collisions in which the knee is jammed against the dashboard, and collisions during contact sports involving hyperextension of the knee are specific scenarios that lead to injuries to this region [5].

SYMPTOMS AND EXAMINATION FINDINGS — Injury to the proximal tibia may present as a knee effusion or as localized swelling and tenderness over the bone. Pain may limit the examination and obscure important findings. Careful skin inspection should be performed to look for puncture or missile wounds, lacerations, and other evidence of an open fracture.

Knee effusion — A knee effusion in a patient with a proximal tibial fracture suggests an osteochondral fracture or an internal derangement (eg, meniscal or ligamentous damage). Aspiration often reveals hemarthrosis, while the presence of lipid droplets or cellular bone marrow elements is indicative of an intraarticular fracture. (See "Overview of hemarthrosis".)

Ligamentous and meniscal integrity — Ligamentous and meniscal injuries frequently occur in conjunction with proximal tibial fractures [6,7]. Pain may interfere with accurate assessment of ligamentous and meniscal integrity. Instillation of local anesthetic into the knee joint may facilitate evaluation of these structures, including the anterior drawer and/or Lachman test of the ACL, the McMurray test for meniscal damage, and varus and valgus stress testing to evaluate the lateral and medial collateral ligaments, respectively. A detailed description of the use of these and other tests in the evaluation of a patient with knee pain is presented separately. (See "Physical examination of the knee".)

More than 10 degrees of opening during varus or valgus stress testing is abnormal. Laxity at the joint line suggests a tear of one of the collateral ligaments, while laxity inferior to the joint line suggests a displaced fracture.

Acute compartment syndrome — Acute compartment syndrome (ACS) refers to a constellation of symptoms and findings that result from compromised perfusion of one or more of the muscular compartments of the lower leg. Blood or edema within an encircling fascia impairs circulation and results in unrelenting pain (main symptom), muscle weakness, and hypesthesia or anesthesia in the skin supplied by nerves that course through the fascially enclosed compartment. Of the four compartments of the lower leg (anterior, lateral, superficial posterior, deep posterior), all border the tibia and can be compromised by tibial injury. Tibial fracture is the most common injury associated with ACS of an extremity.

Tense swelling of the affected muscles, decreased distal pulses, muscle weakness, increased pain elicited by passive stretch of involved muscles, and impaired sensation due to nerve compression or ischemia may be noted on examination. This may progress to pulselessness, paralysis, and anesthesia in advanced cases. Permanent neuromuscular damage may ensue if the compartment pressure is not decreased promptly by fasciotomy. (See "Acute compartment syndrome of the extremities".)

In a retrospective study of 162 tibial plateau fractures, factors associated with an increased risk of ACS included femoral displacement and tibial widening on plain radiographs, as well as a higher (ie, more severe) Schatzker classification (scheme for tibial plateau fractures) [8]. The overall risk for ACS in this study was 11 percent.

DIAGNOSTIC IMAGING — Standard radiographs for suspected proximal tibial fracture include anterior-posterior (AP), lateral, and intercondylar notch views. When clinical suspicion of fracture is high but plain radiographs are equivocal, computed tomography (CT scan) better defines the fracture. Magnetic resonance imaging (MRI) may demonstrate bone bruising and associated meniscus or ligamentous injury [6,7]. For this reason many clinicians prefer to follow standard radiographs with MRI to define the extent of injury when initial imaging is unremarkable.

Diagnostic ultrasound is a useful bedside tool that can identify signs associated with fracture, such as knee effusion or soft tissue injury, and confirm the presence of a cortical step-off [9]. However, ultrasound cannot replace radiographs for establishing the diagnosis of proximal tibial fractures.

DIAGNOSIS — Fractures of the proximal tibia occur most often from direct trauma to the region at or just distal to the knee, and are diagnosed by radiograph. In most instances, plain radiographs are sufficient. (See 'Mechanism of injury' above and 'Symptoms and examination findings' above and 'Diagnostic imaging' above.)

DIFFERENTIAL DIAGNOSIS — The differential diagnosis for pain at or around the knee following acute trauma is reviewed in detail separately. (See "Approach to the adult with knee pain likely of musculoskeletal origin", section on 'Acute knee pain associated with trauma'.)

MANAGEMENT BY FRACTURE LOCATION — Proximal tibial fractures are classified for management purposes as those involving the medial or lateral tibial plateau or the intercondylar notch. Avulsion fractures can also occur at each of these locations. Tubercle avulsion fractures occur primarily in children and adolescents and are discussed separately. Peri-prosthetic tibial fractures have increased with the number of total knee replacements performed but are beyond the scope of this topic. (See "Overview of tibial fractures in adults" and "Proximal tibial fractures in children".)

Tibial plateau fractures

Epidemiology, mechanism, and imaging — Tibial plateau fractures account for approximately one percent of all fractures [10]. They most commonly involve the lateral plateau and occur after a forceful, direct blow to the lateral knee. A review involving a population sample of approximately 576,000 adults found the overall incidence to be 10.3 per 100,000 people annually [11]. In this review, greater numbers of proximal tibia fractures occurred in men (189 men versus 166 women) with the mean age at the time of injury being 52.6 years. Men sustained more injuries when below 50, while women older than 50 sustained markedly more fractures than men. The Swedish Fracture Register found 26.9 proximal tibial fractures per 100,000 population/year with a somewhat older age (54.3 years) on average and 58 percent involving women [1].

Radiographs to obtain include lateral, anterior-posterior (AP; (image 1)), and oblique views (image 2), and these typically reveal a depression of the lateral tibial plateau in moderate to severe fractures. In more subtle injuries, radiographs may appear normal or show only a slight increase in the density of the bone on an AP view.

When clinical suspicion of fracture is high and plain radiographs are equivocal, many clinicians prefer to proceed to magnetic resonance imaging (MRI) because of the ability to visualize bone bruising and associated meniscal or ligamentous injury. Computed tomography (CT) scanning is an alternative if MRI is contraindicated or not available. CT better defines any fracture but does not allow meniscal or ligamentous injuries to be assessed.

Fibular fracture often accompanies tibial plateau injuries. In a group of 502 tibial plateau fractures, associated fibular head fractures occurred in approximately 30 percent [12].

Medial tibial plateau fractures require a higher force as this side of the joint has greater strength. A strong medial force or an axial load such as landing on one's feet after falling from a height are potential mechanisms. When standard radiographs suggest a medial injury, additional imaging may demonstrate simultaneous fractures of both plateaus.

Schatzker and other classification systems are commonly used by orthopedists to describe the location and type of fracture. Schatzker classifies tibial plateau fractures as Types I to VI. The classification helps surgical planning with higher grades requiring more aggressive intervention [13].

Fractures of the tibial intercondylar eminence occur most commonly in children and adolescents as well as in association with anterior cruciate ligament (ACL) injury. (See "Approach to acute knee pain and injury in children and skeletally immature adolescents" and "Proximal tibial fractures in children".)

Indications for orthopedic referral — Emergency (ie, immediate) surgical consultation is required for open fractures and those that cause vascular compromise or acute compartment syndrome (ACS). Fractures with any degree of displacement or depression, even just a few millimeters, or those associated with suspected or documented meniscal or ligamentous injury merit orthopedic consultation within 48 hours. (See "Acute compartment syndrome of the extremities".)

Initial treatment — Compression, icing, appropriate analgesics, splinting of the knee in near-full extension, intermittent elevation of the leg above heart level, and strict non-weight-bearing are the initial treatments for a tibial plateau fracture. Significant injuries are stabilized and orthopedic consultation is obtained.

Most fractures, particularly those sustained from a high energy mechanism, require surgical treatment with open reduction and internal fixation. While plating for proximal extra-articular fractures has been standard, intramedullary nailing is being performed with greater frequency [14,15]. In older adults, patients with advanced osteoporosis or significant osteoarthritis, and younger patients with destruction of the tibial plateau, total knee arthroplasty is often performed [16,17].

For a relatively small subset of fractures without displacement, depression of the tibial plateau, or associated injuries of significance (eg, knee ligament tear), at the first follow-up visit the patient is placed in a hinged brace that is locked in near-full extension and advised to continue non-weight-bearing for the affected extremity, and to ambulate with crutches.

Follow-up care — Uncomplicated proximal tibial fractures without any displacement, depression of the tibial plateau, or associated ligamentous or meniscal injury are amenable to non-operative management by clinicians experienced managing such fractures. After brace fitting, the patient returns weekly for the first three weeks following injury. If there is no displacement at two weeks, the patient begins working on knee flexion in the brace with a goal of achieving 90 degrees by four weeks. Plain radiographs are repeated weekly for three weeks and then on a two to three week basis depending on radiographic appearance.

Strict non-weight-bearing is the norm for six weeks, but this period may be adjusted based on the injury and clinical progress. Partial weight-bearing in the brace can begin once there is adequate radiographic healing (ie, bony callus is present). For surgically repaired fractures, some studies suggest that earlier weight-bearing may be beneficial, but further study is needed [18].

Bracing continues until radiographic healing appears complete – this typically requires 8 to 12 weeks. The patient begins exercises to regain lower extremity strength following removal of the brace. Patients rarely regain full function in less than 12 weeks and more often require 16 to 20 weeks.

Return to sport or work — Once the injured extremity has regained approximately 80 to 90 percent of the strength of the uninvolved extremity, the patient may resume work that does not place undue stress on the leg and may begin sport-specific functional rehabilitation. This particularly applies to non-weight-bearing activities. Healing should be nearly complete before more stressful activity or prolonged weight-bearing is attempted.

Many months may pass before the patient is ready to return to full sporting activity. In a prospective study of 169 patients with proximal tibial fractures treated by a single surgeon and who had participated in recreational sports prior to injury, 48 (31.6 percent) had returned to sport by six months, but only 89 (52.4 percent) had returned by final follow-up at 15 months [19]. Patients with less severe injuries and no postoperative complications returned to sport more quickly. Increased knee range of motion is associated with successful recovery.

Outcomes and complications — ACS is the most common, significant short-term complication associated with tibial fracture. ACS is a limb-threatening emergency and immediate orthopedic consultation is required when the diagnosis is suspected. (See 'Acute compartment syndrome' above.)

Proximal tibia fractures are frequently sustained in motor vehicle collisions or other major traumatic events in which patients suffer other severe injuries, which often delays the return to daily activity. Given the high-energy trauma often involved in proximal tibial fractures, complications occur with some frequency and may include infection, nonunion or malunion, and stiffness of the knee. The most severely traumatized open fractures of the tibia require amputation in approximately 2 percent of cases overall, but the rate is lower with fractures of the proximal tibia [20].

Nevertheless, overall outcomes are generally good over the short term, although data is limited. In an observational study of 244 tibial plateau fractures treated surgically, 190 had what were considered good outcomes, but 54 had significant long-term morbidity [21]. Outcomes are generally better in younger patients. A retrospective study of 47 tibial plateau fractures treated surgically found that patients younger than 40 years experienced substantially less disability compared to age-matched controls than older patients compared to their controls [22]. (See "General principles of fracture management: Early and late complications".)

Fractures of the proximal tibia that become infected can cause severe long-term morbidity. Multiple surgical revisions are often required, and nonunion sometimes results despite such interventions. In a meta-analysis of 32 primarily observational studies, 55.8 percent of cases with deep infection (72 of 129) led to long-term problems with the use of the injured extremity [23].

One important functional complication following tibial plateau fractures is an inability to regain normal gait. According to a small case-control study, following this injury patients showed slower cadence and shorter stride length, such that walking speed declined 18 percent compared to controls. These patterns persisted after three years [24].

The major long-term complication of tibial plateau fractures is osteoarthritis of the knee. In a review of over 7000 proximal tibia fractures, the need for total knee arthroplasty was 1.8 to 3.2 times greater among fracture patients during the first five years following injury compared with controls [25]. However, radiologic findings one year following injury, even when some arthritic change was noted, were not found to be accurate predictors of diminished function over the mid to long term [10].

Difficulty recovering normal gait is an important complication and contributes to the relatively high number of patients who develop ankle osteoarthritis. Other complications include chronic pain over the fracture and any surgical incision sites, as well as thinning and irritation of overlying skin. All of these long-term complications occur more frequently in patients over 40 and in those with comorbidities such as diabetes.

Data pertaining to long term outcomes is limited, but it appears that many patients experience some decline in function:

●Researchers in one study used a validated assessment instrument (KOOS score) to survey 71 patients 5 to 11 years following surgical repair for a tibial plateau fracture and found that many reported clinically significant reductions in overall functional outcomes and knee-related performance in sport and recreation activities [10].

●In a similar study with six-year follow-up, knee-related outcomes for 82 patients were rated as fair and functional outcomes for sport and recreation as poor [26]. In addition these patients rated their health-related quality of life lower than an age-matched population. High energy trauma was associated with poor outcomes.

●In a retrospective case series of 22 patients who sustained high-energy tibial plateau fractures (Schatzker IV, V, or VI) requiring treatment with internal or external fixation, at follow-up (mean 56 months) nearly all patients demonstrated some arthritic change, just over three-quarters experienced chronic pain, about half noted mobility impairments, one-third could no longer perform all their prior activities, and a little over one-quarter had limits in self-care [27].

A long-term population-based cohort study of 8426 patients compared with controls matched for age, sex, and income found that tibial plateau fractures requiring surgery significantly increased the likelihood (5.3 likelihood ratio [LR]) of total knee replacement [28]. At 10 years, 7.3 percent of patients required such replacement. A similar study in Denmark of 7950 patients with tibial plateau fractures reported a comparable risk for total knee replacement [29].

Anterior tibial spine and intercondylar notch fractures — Avulsion of the anterior tibial spine is particularly common in skeletally immature adolescents but can also occur in young adults. Adults with the same mechanism of injury are more likely to sustain a tear of the anterior cruciate ligament. With avulsion, the affected knee often has a significant effusion and aspiration may show blood and or fat indicative of an intraarticular fracture. The treatment of avulsion of the anterior tibial spine is discussed in greater detail separately. (See "Proximal tibial fractures in children", section on 'Tibial spine avulsion'.)

Whether these fractures occur in skeletally immature or mature patients seems to have little effect on long-term outcomes. In a series of 37 cases that required surgical fixation of the tibial spine followed for a mean of 16 years, two patients developed osteoarthritis of the knee. Using functional scores (WOMAC, Lysholm), 86 percent were classified as having good to excellent results. Knee examination demonstrated stability and adequate flexion (average 130 degrees). The 16 patients in this cohort with open growth plates at the time of injury did not develop malalignment or malrotation [30].

Tibial tubercle avulsions — Tubercle avulsions occur at the apophysis of the anterior tibia where the patellar tendon attaches. These injuries are rare, representing less than one percent of physeal fractures. A few case reports describe bilateral avulsions. The mechanisms most often noted are knee flexion at the beginning of a jump or an awkward landing [31]. Plain radiographs demonstrate displacement of a reasonable sized fragment (image 3). In adolescents, an unfused growth plate may cause confusion with an avulsion fracture. The treatment of avulsion of the anterior tibial tubercle is discussed separately. (See "Proximal tibial fractures in children", section on 'Tibial tubercle avulsion'.)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: Lower leg fracture (The Basics)")

ADDITIONAL INFORMATION — Several UpToDate topics provide additional information about fractures, including the physiology of fracture healing, how to describe radiographs of fractures to consultants, acute and definitive fracture care (including how to make a cast), and the complications associated with fractures. These topics can be accessed using the links below:

●(See "General principles of fracture management: Bone healing and fracture description".)

●(See "General principles of fracture management: Fracture patterns and description in children".)

●(See "General principles of definitive fracture management".)

●(See "General principles of acute fracture management".)

●(See "General principles of fracture management: Early and late complications".)

SUMMARY AND RECOMMENDATIONS

●Mechanism – Proximal tibial fractures usually result from a fall, motor vehicle crash, vehicle pedestrian collision, or an injury during participation in a contact sport. (See 'Mechanism of injury' above.)

●Concomitant injury – Concomitant injury to the stabilizing ligaments and/or the medial or lateral meniscus often occurs with proximal tibial fractures. These additional injuries should be suspected, assessed by physical examination, and further evaluated by MRI when clinically indicated. (See 'Symptoms and examination findings' above.)

●Indications for referral – Displaced fractures, depressed tibial plateau fractures, intraarticular fractures, associated ligamentous tears, and/or meniscal damage warrant orthopedic referral within 48 hours. (See 'Indications for orthopedic referral' above.)

Open fractures and those with vascular injury or suspected compartment syndrome require immediate orthopedic referral. (See 'Acute compartment syndrome' above.)

●Management – Splinting for tibial plateau fractures is in full extension, while splinting for intercondylar fractures is in 5 to 10 degrees of flexion. (See 'Initial treatment' above and 'Anterior tibial spine and intercondylar notch fractures' above.)

Initial management includes splinting, analgesia, and non-weight-bearing with crutches.

●Outcomes – When managed promptly and appropriately, non-displaced and uncomplicated proximal tibial fractures in individuals less than age 40, even those involving an open physis, have good outcomes, including return to sport and occupational activities. However, patients with more complicated injuries who require surgical repair often develop complications, which may include gait abnormalities, knee osteoarthritis, ankle osteoarthritis, and overall diminished function and quality of life. (See 'Outcomes and complications' above.)