Multiligament Injured Knee Dislocation

This article is currently under review and may not be up to date. Please come back soon to see the finished work! (6/11/2026)

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Introduction

Figure 1. Illustration of a multiligament knee dislocation, showing complete disruption of all four major stabilising ligaments: the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), and fibular collateral ligament (FCL), with associated injury to the popliteus tendon.

A multi-ligament knee injury (MLKI) is an injury involving two or more of the major ligamentous structures of the knee, a definition spanning presentations from a neurovascularly intact bicruciate injury to a grossly unstable, pulseless dislocation requiring emergent management. For years this spectrum was described with inconsistent terminology, with “multi-ligament injury” and “knee dislocation” often used interchangeably, which complicated comparison of cases, outcomes and research findings across centres. The 2024 international expert consensus statement established a clear, widely adopted operational definition of MLKI, resolving this ambiguity.

Knee dislocation refers specifically to complete displacement of the tibiofemoral joint, the femur and tibia losing all normal articular contact (Figure 1), rather than subluxation or gapping under stress, and by definition represents a multi-ligament injury, since that degree of displacement cannot occur without disrupting at least two of the four major ligament complexes. Two- and three-ligament injuries, by contrast, frequently remain reduced. A clinically important subtlety, discussed further under Assessment, is that a meaningful proportion of dislocations reduce spontaneously before the patient is examined, so a knee that looks merely swollen and unstable may have been fully dislocated only minutes earlier.

Clinically relevant anatomy

Multi-ligament injuries are complex in nature and can involve many structures, including:

Cruciate Ligaments

The anterior cruciate ligament (ACL) runs from the posteromedial aspect of the lateral femoral condyle to the anterior tibia and is the primary restraint to anterior tibial translation and rotational instability. The posterior cruciate ligament (PCL), its mirror image, runs from the lateral aspect of the medial femoral condyle to the posterior tibia and resists posterior tibial translation; it is the strongest ligament in the knee, which is precisely why an injury severe enough to tear it is rarely limited to the PCL alone.

Collateral Ligaments and Corners

On the medial side, the medial collateral ligament (MCL) and the posteromedial corner (principally the posterior oblique ligament and the posteromedial capsule) resist valgus opening and, together with the posteromedial capsule, internal rotation. On the lateral side, the posterolateral corner (PLC) is a compact but mechanically vital complex made up of the fibular collateral ligament, the popliteus tendon, and the popliteofibular ligament; together they resist varus opening, external rotation, and posterolateral tibial translation. A posterolateral corner injury is easy to miss on a cursory examination and is one of the more common causes of a failed cruciate ligament reconstruction when it goes unrecognised.

Neurovascular Anatomy

Two neurovascular relationships explain why multi-ligament injuries are managed so differently from an isolated ligament tear, and both relate to the popliteal fossa, the diamond-shaped space behind the knee through which the major neurovascular structures pass on their way from thigh to calf. The popliteal artery is tethered proximally at the adductor hiatus, where it passes through the adductor magnus, and distally at the soleal arch, where it dives beneath the soleus muscle. Fixed at both ends, it has very little slack to accommodate a sudden displacement of the tibiofemoral joint, and can be stretched, kinked or torn even when the knee has already reduced by the time it is examined. The common peroneal nerve takes a more superficial and more exposed course: it splits from the sciatic nerve above the knee, runs along the medial border of the biceps femoris tendon, and then wraps directly around the neck of the fibula, immediately adjacent to the posterolateral corner and covered by little more than skin and fascia at that point. This superficial position is exactly why posterolateral and varus-type injuries carry a disproportionate risk of peroneal nerve injury and the foot drop that follows it.

Classification

Ligament combination has long been used as a shorthand for describing these injuries, most influentially through the Schenck (KD) classification, which grades injuries by how many ligament complexes are disrupted: KD I involves a single cruciate ligament; KD II involves both cruciate ligaments with both collaterals intact; KD III adds one collateral to a bicruciate injury, subdivided into KD IIIM (medial) and KD IIIL (lateral) depending on which side is torn; KD IV involves all four major ligament complexes; and KD V denotes a dislocation with an associated periarticular fracture. The 2024 consensus process built on this foundation and called for classification to also capture the mechanism of injury and the extent of non-ligamentous damage, fracture, meniscal or cartilage injury, nerve injury, rather than relying on ligament count alone. A classification built around mechanism and associated injury, and not just which structures are torn, tracks much more closely with what actually predicts risk, and in particular the risk of an associated vascular injury, which is the single finding most likely to change the first hour of management.

Epidemiology

Mechanism of Injury

Multi-ligament knee injuries result from two distinct injury mechanisms:

High-energy trauma, including motor vehicle collisions, motorcycle crashes, falls from height, and industrial accidents, exposes the knee to forces well beyond the physiological limits of its ligamentous structures. A recognised example is the dashboard injury, in which a flexed knee strikes the dashboard during a frontal collision, driving the tibia posteriorly relative to the femur and tearing the posterior cruciate ligament, frequently in combination with the posterolateral corner when a rotational component is present.

Low-energy sporting trauma, such as an awkward landing, a hyperextension moment, or a planted foot combined with a rotational force, can produce ligamentous damage of comparable severity despite a considerably less dramatic mechanism.

A third, increasingly recognised pattern is the ultra-low-velocity dislocation observed in patients with obesity, in which increased body habitus raises the lever arm and load across the knee such that a minor misstep or change of direction while standing can result in dislocation.

Typical ligament sprain mechanism of injury:

• ACL (anterior dislocation): Hyper-extention force
• PCL (posterior dislocation): Posterior force (e.g. dashboard injury)
• MCL (medial dislocation): Valgus force (often associated with tibial plateau fractures)
• LCL (lateral dislocation: Varus force (often associated with tibial plateau fractures)
• Rotary dislocation: Combination of forces

Associated Injuries

Associated injuries are common rather than exceptional, and clinicians should actively screen for them rather than rely on incidental detection. Meniscal tears, chondral damage, periarticular fracture, and neurovascular injury all occur with meaningful frequency alongside the ligamentous injury itself; a systematic review of vascular and nerve injury after knee dislocation confirmed that both occur frequently enough to justify screening in every case, not only those with an overtly dramatic presentation. The medial meniscal ramp lesion, a tear at the posterior meniscocapsular junction, warrants particular attention: it is present in more than a third of patients with an intact anterior cruciate ligament and is easily missed unless the posteromedial compartment is specifically visualised, rather than relying on standard anterior arthroscopic portals alone.

Clinical Presentation

Assessment should include observation, followed by vascular status, neurological status, and finally ligamentous testing to demonstrate the degree of instability. It is very important to do thorough and repeated evaluation of the neurological and vascular status for signs of injury to the common peroneal nerve, popliteal artery and to assess for compartment syndrome.

Most multi-ligament knee injuries are easily reducible with minimal assistance or even spontaneous. Dislocation can be suspected based on physical exam findings of joint instability/ligamentous injuries, but also based on hemarthrosis and tenderness upon palpation. It is often difficult to diagnose if a reduced knee was dislocated or subluxed without clinical witness or radiological evidence. Associated meniscal, osteochondral, and neurovascular injuries are often present and can complicate management.

Observation

Observation should always be performed bilaterally, since the appearance of the injured knee is best interpreted in comparison with the uninjured limb. Key observation markers include gross deformity at presentation, or a documented history of deformity that has since been reduced, which should raise suspicion of MLKI even when the knee appears only swollen on examination.

A large, tense hemarthrosis suggests an intracapsular injury, such as a cruciate tear, a peripheral meniscal tear, or a fracture, whereas a knee that remains relatively soft despite a clearly unstable history suggests a capsular disruption extensive enough to allow haemorrhage to decompress into the surrounding soft tissues rather than the joint itself; this latter finding should be regarded as the more concerning of the two.

The distribution of ecchymosis can also be informative. Posterior and lateral bruising over the fibular head suggests posterolateral corner involvement and should raise suspicion for an associated peroneal nerve injury even before formal neurological testing, while medial bruising over the joint line suggests involvement of the medial collateral ligament and posteromedial corner.

Tenting or dimpling of the skin over the medial femoral condyle, known as the pucker sign, is one specific finding that warrants particular attention and indicates that the condyle has buttonholed through the joint capsule and signals that closed reduction is unlikely to succeed.

Vascular assessment

Vascular assessment takes precedence over ligamentous testing because the consequences of a missed popliteal artery injury, which can result in limb loss, are substantially greater than those of a delayed ligament reconstruction, which at most results in a delay of several weeks. This sequence is recommended even when the knee appears obviously unstable and ligamentous testing seems the more immediate priority. This precedence stems largely from a landmark 1970s series demonstrating that vascular injury after knee dislocation was common and, notably, not reliably predicted by the presence of a normal pulse. In practice, this means inspecting the limb for pallor, mottling, or a cool distal segment, palpating the dorsalis pedis and posterior tibial pulses bilaterally for comparison, and assessing capillary refill before any varus or valgus stress is applied.

The ankle-brachial index remains the standard screening tool, with a threshold of 0.9 first validated in a prospective series of knee dislocations and still the figure in routine use today, though a palpable pulse on its own is not reassuring enough to exclude an intimal injury, a partial tear of the vessel wall that can thrombose hours later despite a normal initial pulse examination. Current guidance favours a low threshold for CT angiography whenever the mechanism is high-energy, or when the injury pattern involves both cruciate ligaments or the posterolateral corner, since these patterns correlate most strongly with vascular compromise.

A knee that has spontaneously reduced by the time of examination has nonetheless undergone the same degree of displacement as one still dislocated and requires the same vascular work-up, repeated serially if the initial examination is reassuring but the mechanism of injury was concerning. A smaller but clinically important subset of dislocations are irreducible at presentation, typically because the femoral condyle has buttonholed through a rent in the joint capsule (the pucker sign described above); closed reduction is not possible in this situation. Repeated attempts at manipulation under sedation should be avoided, and vascular status should continue to be monitored closely while open reduction is arranged.

Neurological assessment

Common peroneal nerve function requires specific, individual attention and documentation during an assessment. This requires testing ankle and great toe dorsiflexion against resistance, testing eversion, and mapping light-touch sensation over the dorsum of the foot and lateral leg. Tibial nerve function should be assessed alongside it, despite being injured far less frequently, by testing ankle and toe plantarflexion and sensation over the sole of the foot. A foot drop identified on initial examination, in which the patient is unable to clear the foot in swing or dorsiflex against gravity, represents a distinct clinical problem, with a different prognosis, from a deficit that develops only after a period of documented normal function, which more often indicates an evolving traction or compression injury rather than a complete nerve disruption at the time of injury. This distinction underscores the importance of accurately documenting nerve function at initial assessment, before splinting, bracing, or surgical intervention can obscure the clinical picture.

Ligamentous assessment

Once the limb is confirmed to be vascularly intact, ligaments can then be accessed systematically. Two practices improve the reliability of this examination:

• Testing the uninjured leg first, so that the patient’s own normal endpoint is established for comparison
• Grading findings quantitatively rather than recording them simply as positive or negative. In an acutely swollen, guarded knee, grading is often provisional and should be repeated once the patient is more comfortable or under anaesthesia, since guarding alone can cause a genuinely unstable knee to feel falsely firm. Please see the ligament sprains page for more information.

Examination should also proceed from tests requiring the least patient cooperation toward those requiring the most where possible.

The following ligament tests may be used as part of your assessment:

Posterior sag (Godfrey) test

The Posterior sag (Godfrey) test is performed with both hips and knees flexed to 90 degrees and the examiner supporting the heels, the tibia is observed from the side for a posterior sag relative to the femoral condyles. Since this test relies on gravity rather than an applied force, this is often the first and most reliable indicator of a PCL injury in a guarded patient, though it is frequently overlooked when not specifically assessed.

Quadriceps activation test

Quadriceps active test is performed from a 60–90-degree flexed position. The patient is asked to gently contract the quadriceps while the examiner observes the tibia. In a PCL-deficient knee, the tibia visibly translates anteriorly as quadriceps contraction reduces the posterior sag, a useful confirmatory sign alongside the posterior drawer that requires only a gentle muscle contraction rather than a manual stress test.

Lachman test

Lachman test is performed with the knee flexed to around 20–30 degrees, for the anterior cruciate ligament, checking the tibial step-off before testing, a posterior sag from a PCL injury can easily be mistaken for a positive anterior drawer or an unusually soft Lachman endpoint if the step-off is not checked first.

Pivot Shift Test

The pivot shift test begins with the knee starting in extension, the examiner applies internal rotation and a valgus force to the tibia while slowly flexing the knee, feeling for a palpable reduction, or clunk, as the tibia relocates at around 20 to 30 degrees of flexion.

Reverse Pivot Shift Test

Reverse pivot shift test involves taking the knee from flexion towards extension while applying a valgus and external rotation force: in a posterolateral corner injury the tibia sits subluxated posteriorly in flexion and reduces with a palpable clunk at around 30 degrees as the knee approaches extension, essentially the mirror image of the pivot shift used for the anterior cruciate ligament, and a useful cross-check when the dial test and posterolateral drawer point the same way.⁵¹

Anterior Drawer Test

The Anterior Drawer Test is typically not recommended as the reliability is compromised as a result of pain, loss of range of motion and muscle spasms.

Posterior Drawer Test

The Posterior drawer test starts with the knee flexed to 90 degrees and the foot stabilised in neutral rotation, and tibial step-off for the posterior cruciate ligament, grading by how far the tibia falls posteriorly relative to the femoral condyles compared with the uninjured side.

Posterolateral Drawer Test

The posterolateral drawer test is a variation performed with the knee flexed to around 80 degrees and the tibia internally rotated roughly 15 degrees: a posteriorly directed force is applied to the proximal tibia, and excessive posterolateral rotation of the tibia compared with the uninjured side corroborates what the dial test suggests, rather than relying on rotation alone.

Valgus Stress Test

The valgus stress test begins at 30 degrees and in full extension for the medial structures; opening confined to 30 degrees suggests an isolated superficial MCL injury, while opening in full extension implies a more severe injury involving the posteromedial corner and possibly the cruciates as well.

Varus Stress Test

The varus stress test begins at 30 degrees and in full extension for the lateral structures, with the same logic in reverse: opening in full extension signals a more complex posterolateral corner injury rather than an isolated lateral collateral ligament sprain.

Dial test

The dial test is performed at 30 and 90 degrees, in prone or supine with both knees flexed together and comparing the degree of external rotation of the feet, to distinguish an isolated posterolateral corner injury from a combined posterolateral and posterior cruciate injury: increased external rotation at 30 degrees only, which resolves by 90 degrees, suggests an isolated PLC injury, while increased rotation persisting at 90 degrees suggests combined PCL and PLC involvement.

External Rotation Recurvatum Test

External rotation recurvatum test involves lifting both legs off the examination table by the great toes with the knees fully extended: excessive hyperextension and external rotation of the tibia on the affected side, compared with the uninjured leg, is another sign of combined posterolateral and cruciate laxity and is a useful test precisely because it needs no active cooperation from a guarded patient.

Diagnostic Procedures

It is easy to diagnose the unreduced knee, but as most cases present already reduced, it is important to do a thorough evaluation to make an accurate diagnosis and to exclude any potential associated injuries. Where the examination remains equivocal, which it often does, in an acutely swollen and guarded knee, stress radiography or intraoperative fluoroscopy add useful objective information that does not depend on the patient's ability to relax through pain. Knee dislocation often goes hand-in-hand with concomitant injuries to other structures such as nerves and blood vessels. It is very important to do a neurovascular assessment to exclude injuries to perineal nerve and popliteal artery. For the posterolateral corner specifically, the dial test, posterolateral drawer and external rotation recurvatum test are best interpreted alongside MRI or bilateral hip-to-ankle films, the last of these picking up any pre-existing varus or valgus alignment that will need to be addressed for a reconstruction to succeed.

Diagnostic investigations

Diagnostic investigations may include:

• X-rays: AP and lateral views should be routinely done in suspected knee dislocations due to high incidence of associated fractures
• Doppler ultrasound: To assess the blood flow in the arteries
• Ankle-brachial index: Can be used to determine if angiography is needed (threshold of <0.9 can positively predict a vascular injury in need of surgery)
• Arteriography: Recommended if there are abnormal findings with the ankle-brachial index, as well as previous history of ischaemia or any present signs of ischaemic or circulatory compromise
• MR angiography: Can be used in the acute setting as an alternative to arteriography
• MRI: Can be used to aid surgical planning

Outcome Measures

• Lysholm score
• International knee dislocation score
• Multi-ligament Quality of Life questionnaire
• International Knee Documentation Committee Subjective Knee Form

Management

Current consensus favours operative management for most patients with MLKI, particularly when they are younger and active, since the combination of ligaments involved rarely leaves the knee functionally stable enough for daily activity, let alone sport, without reconstruction. Non-operative treatment is reserved for patients unfit for surgery on medical grounds, or for specific injury patterns, for example, an isolated bicruciate injury with intact collaterals in a low-demand patient, where the residual instability may be tolerable.

Surgical Interventions

Single stage versus staged reconstruction

Where possible, single-stage reconstruction of all injured structures is preferred over a staged approach. Operating on everything at once avoids the interval attenuation of ligaments left untreated while the patient waits for a second procedure, and it spares the patient a second general anaesthesia and a second, separate rehabilitation clock, an argument first made systematically in a large single-centre series comparing surgical strategies for knee dislocation, which remains one of the most frequently cited outcome papers in this field. The trade-off is technical complexity: fitting four ligament reconstructions into one knee, one operating list and a small volume of bone requires careful sequencing, from graft harvest through tunnel drilling to final fixation. Modern tunnel planning has made this more achievable: anatomic reconstruction of all four ligament complexes can now be addressed in a single setting while still limiting tunnel convergence, the phenomenon in which two tunnels drilled from different directions intersect inside the bone and compromise fixation of one or both grafts.

Timing of Surgery

Surgery is usually undertaken once the acute swelling has settled and a functional range of motion has been restored, typically around two to three weeks after injury, although the exact timing is always individualized to the patient, the injury pattern and the state of the soft tissues. Concomitant meniscal or neuromuscular injury can shift this timeline in either direction: a repairable meniscal tear may push surgery earlier to protect the repair, while a peroneal nerve injury under observation may push it later. The balance to strike is a narrow one. Operate too early into a swollen, stiff knee and the risk of arthrofibrosis, the knee scarring down and losing motion before it has had the chance to move, rises sharply; wait too long and the ligament ends retract, the tissue planes scar together, and anatomic reconstruction becomes technically much harder to achieve.

Figure 2. Double-bundle PCL reconstruction, recreating the anterolateral and posteromedial bundles from separate femoral tunnels with fixation on a common tibial tunnel

Surgical considerations relevant to rehabilitation

Multi-ligament reconstruction packs several tunnels into a small volume of bone around the knee, and tunnel convergence is a well-recognised technical problem that has shaped how these procedures are planned and sequenced.

Posterior Considerations

Graft choice is important, particularly for the posterior cruciate ligament. Double-bundle reconstruction, which restores both the anterolateral and posteromedial bundles, more closely reproduces native anatomy, and this holds up regardless of graft source, since autograft and allograft perform comparably once a double-bundle technique is used, unlike single-bundle reconstruction, where autograft leaves less residual posterior tibial translation and better clinical outcomes than Achilles tendon allograft. The order in which grafts are tensioned and fixed also affects the final result, since each ligament that is fixed changes the resting position of the joint that the next graft is tensioned against, which is part of why these cases are best done by surgeons and teams with specific experience in multi-ligament reconstruction.

Posterolateral Corner Considerations

Figure 3. Posterior view of a two-graft anatomic PLC reconstruction, restoring the fibular collateral ligament, popliteus tendon, and popliteofibular ligament attachments.

The posterolateral corner is generally treated more aggressively than the other structures, because it tolerates residual laxity particularly poorly and because a missed or under-treated PLC injury is a well-known cause of early failure of an otherwise well-placed cruciate ligament graft. Isolated repair of a complete tear is now discouraged without augmentation or reconstruction. This position has a long track record: an early comparative series showed reconstruction outperforming primary repair for these injuries two decades ago. More recent outcome data reinforce this, with anatomic reconstruction techniques (Figure 3), which recreate the individual fibular collateral, popliteus and popliteofibular components rather than using a single non-anatomic sling, fail substantially less often than non-anatomic reconstructions, roughly 4 to 24 percent compared with 0 to 36 percent. Peroneal nerve injury, residual laxity and stiffness remain the complications most often reported afterwards, and patients should be counselled about all three before surgery, not just the risk of the operation failing to restore stability.

Medial Side Considerations

The medial side is treated more conservatively where possible, reflecting its generally better capacity to heal with non-operative or repair-based treatment. Repair and reconstruction give comparable patient-reported outcomes for grade III medial injuries, with fewer complications reported after repair, so the choice tends to come down to tissue quality, whether there is enough healthy ligament left to repair, and how chronic the injury is by the time it reaches surgery, rather than a fixed rule applied to every patient. When reconstructed, an MCL augmentation or a Laprade’s technique are the preferred by the senior author (Figure 4).

Figure 4. (A) Augmentation of the MCL. (B) Anatomic reconstruction of the posteromedial corner.

For therapists, the practical implication of all of surgical intervention is that the rehabilitation programme is dictated by which structures were reconstructed, with which grafts, and in what condition the surrounding soft tissues were left, not by the diagnosis of MLKI alone. The operative note should be obtained and read before the first rehabilitation session is planned, not requested after a setback has already occurred.

Rehabilitation After Multi-ligament Reconstruction

Rehabilitation after multi-ligament reconstruction is a long process, individualised to the structures reconstructed, and it only works with close, ongoing communication between therapist and surgeon, rather than a single handover conversation at the first postoperative visit. Surgery aims to restore the anatomical structures with sufficient strength. Passive and active of the assisted range of motion rehabilitation is needed. Most patients lose range of motion and do not recover entirely after surgical intervention for a multi-ligament injured knee.

The two competing risks that define this rehabilitation, arthrofibrosis on one side, graft attenuation (a healing graft gradually stretching out under load applied too early or too aggressively) on the other, stay in tension throughout the whole recovery, and the program below is best read as a continuous negotiation between them rather than a fixed script to be applied identically to every knee (Figure 5). A published surgical technique and postoperative protocol for posterolateral corner reconstruction is a useful reference for that component of the plan, since PLC-specific restrictions often drive the pace of the whole programme.

Post-surgical rehabilitation for this injury varies according to the ligaments that were injured and repaired. An accelerated rehabilitation programme with knee bracing and early range of motion training has shown to decrease stiffness. The following is a rough guideline for a rehabilitation programme across four distinct phases, over a 12 month period, but it is important to assess each patient individually to create a customised rehabilitation programme taking their goals and expectations into account.

Phase 1: 0 to 6 weeks

• Bracing and weight-bearing status determined by the specific reconstruction. Posterior cruciate and posterolateral corner reconstructions are typically protected more conservatively, since these grafts are more vulnerable to the posterior and varus forces generated by early weight-bearing and hamstring activity.
• Early controlled range of motion to reduce the risk of arthrofibrosis, within surgeon-specified limits, accepting a slower return of terminal flexion in exchange for protecting the graft.
• Prone or supported knee flexion for posterior cruciate reconstructions, avoiding posterior tibial sag, which would place the healing graft under sustained stretch. Hamstring activity is avoided in this group for the same reason, since the hamstrings pull the tibia posteriorly.
• Quadriceps activation, patellar mobilisation, and oedema management, all of which are important at this stage as a quadriceps that fails to fire early is difficult to recover fully later, and a patella left immobilised can scar down within weeks.
• Peroneal nerve status requires monitoring, with an ankle-foot orthosis often recommended and maintenance of ankle range of motion where a foot drop is present, to prevent a fixed equinus contracture from developing on top of an already compromised nerve.

Goals: full passive extension, protected flexion progression, effective quadriceps contraction.

Phase 2: 6 to 12 weeks

• Progressive weight bearing to full, with brace weaning as directed by the surgeon rather than by how the knee feels.
• Progression to full flexion, now that the early graft-protective window has passed.
• Introduction of closed-chain strengthening within protected ranges, favouring exercises that load the joint through compression rather than shear.
• Gait retraining, proprioceptive work, and stationary cycling, rebuilding the basic movement patterns that months of protection have allowed to deteriorate.

Phase 3: 3 to 6 months

• Progressive resistance training, addressing the substantial quadriceps deficit typical at this stage, which is usually the single biggest limiter of function.
• Single-limb loading, balance and neuromuscular control, building the confidence to trust the knee under less predictable conditions.
• Hamstring strengthening introduced later in posterior cruciate reconstructions, once the graft has matured enough to tolerate posteriorly directed load.

Phase 4: 6 to 12 months

• Running introduced when strength and control criteria are met, not on a fixed calendar date.
• Progression through change of direction and sport-specific work where relevant, building complexity gradually rather than returning to full training in one step.
• Return to pivoting sport is a criterion-based decision, typically not before nine to twelve months, and is not achieved by all patients, a fact that should be discussed honestly well before this stage is reached, not for the first time when it arrives.

Figure 5. Four-phase, criterion-based rehabilitation protocol following multi-ligament knee reconstruction, summarising key interventions and goals.

Surgical Outcomes

Outcomes after multi-ligament reconstruction are generally good in terms of restoring a stable knee for daily activity and recreational function, and many patients do return to sport. Patients should nonetheless be counselled, ideally more than once and starting early, that the knee is unlikely to return to its pre-injury state, that stiffness is the most common complication, and that rehabilitation is measured in many months rather than the weeks that follow an isolated ligament reconstruction. Honest expectation setting at the outset, however uncomfortable that conversation feels in the first postoperative weeks, is more useful to the patient than optimism that must be revised downwards at six months, once the gap between what was promised and what has been achieved has already started to erode trust.

A systematic review of studies following patients for at least seven years after MLKI found that patient-reported outcomes and return-to-activity rates hold up well over time, which is genuinely reassuring, but it also confirmed that a meaningful share of patients never return to their pre-injury level of sport, and that stiffness and post-traumatic osteoarthritis remain the most commonly reported long-term problems. Framed for a patient early in their recovery, this evidence supports real optimism about function and stability, alongside honesty about the fact that some loss, whether of motion, of sporting level, or of the knee's long-term durability, is a plausible part of the outcome and not a sign that something has gone wrong.

Conservative management

Conservative treatment depends on the amount of damage to the different structures. Each patient will experience a different management plan depending on the current stability of the patient, and eventually the other associated injuries. The goal of physiotherapy is to restore stability and regain pain-free functional mobility.

A therapist may initially use a limiting range of motion brace to allow for the healing of the capsule and collateral ligaments. This will restore varus and valgus stability. During early exercises, wearing a range of motion brace is important to limit flexion to 90° and extension to 45°.

The following may be used as part of the rehabilitation process and is documented in order of recommended progression. Each patient should be specifically evaluated before attempting the specific treatment modalities.

• Cardiovascular conditioning: Upper and midbody exercises, along with single-leg stationary bicycling
• Quadriceps strengthening: Very important to prevent patellofemoral problems during rehabilitation
• Light manual-resistance exercises between 45°-90°
• Biodex
• Manual therapy
• Leg-press machine > 8 weeks of rehabilitation. During this face, the knee needs only minimal protection. These exercises should be followed by
• High-speed exercises with light resistance
• Proprioception (once range of motion and muscle power has been regained)

Clinical Bottom Line

Multi-ligament knee injuries range from stable bicruciate tears to limb-threatening dislocations, and many dislocated knees reduce spontaneously before examination. A high-energy mechanism or a history of deformity should be treated as a possible dislocation. Assessment should always move from observation to vascular and then neurological status before ligament testing. A normal pulse does not exclude popliteal artery injury, so there should be a low threshold for further vascular imaging. Peroneal nerve function should be documented at the first assessment, and the posterolateral corner should be examined specifically because it is easily missed.

Most active patients are best managed with single-stage surgical reconstruction at around two to three weeks after injury. Rehabilitation is guided by the structures reconstructed, so the operative note should be read before treatment begins. Over about twelve months, rehabilitation balances the risk of stiffness against the risk of the graft stretching, and progression should be based on criteria rather than dates. Outcomes for stability and daily function are generally good, but stiffness, reduced sporting level and osteoarthritis are common, so patients benefit from early, honest expectation-setting.