Is Multiligament Knee Injury (MLKI) Still a Challenge in 2024?

Multiligamentous knee injuries are an essential topic of discussion amongst orthopaedic surgeons due to their rarity and dreaded sequelae if there is a lapse in treatment. These injuries are often difficult to diagnose and treat. There are challenges in deciding surgical plans with incertitude regarding the optimum timing of surgery, type of surgical procedure, graft selection and postoperative rehabilitation protocol to suit the patient’s needs.

Due to their rare and variegated nature, more high-quality clinical data on MLKI must be included. There has yet to be a consensus on managing these complex injuries. The only data pertains to various level 3 and 4 studies describing multiple surgical techniques for managing MLKI. This increases the importance of compiling expert opinions on the topic, making them invaluable.

The editors have dedicated this special issue to MLKI and made the essential information on the topic more accessible. They have included additional pearls on surgical techniques and new cases and techniques to help readers better understand the enigma of these complex injuries.

Where are we now?

We have acquired some knowledge on the topic through pre-existing literature, which somewhat guides the management and provides some direction to the treatment doctor.

Diagnosis

These injuries are often missed and misdiagnosed, especially when an associated PLC and PMC injury is in the affected knee. Various authors have emphasised the importance of a detailed physical examination, MRI and stress radiographs in cases with suspected knee dislocations [1, 2]. In cases of chronic knee laxity, the inevitable role of long leg and stress radiographs has been described in excellent detail [3, 4]. As much as correctly identifying these injuries at presentation is desirable, it is even more critical to assess the distal neurovascular status of the affected limb.

Timing of Surgery

Recent literature supports acute surgical management of MLKI within three weeks of the injury and has shown good to excellent postoperative outcomes [5]. Dr Vaishya has very nicely addressed this topic in the special issue of IJO on MLKI. The timing of the injury mainly relies on the DNVS of the affected limb at presentation. Ligament reconstruction has to be delayed in the event of a vascular injury or extensive soft tissue loss over the affected knee at the time of presentation. Bancha has described this topic very wisely in the current special issue. A few authors have also advocated delaying operative procedures in cases where the affected knee has frank instability even after using a knee brace, which usually demands treatment using an external fixator application [6]. The choice between hinged and non-hinged external fixators and their relative advantages remains controversial. External fixator use is associated with complications like knee stiffness and superficial and deep infections. No studies support their use of knee braces [7, 8].

Graft Selection

Allograft and autograft use have demonstrated satisfactory postoperative outcomes [9] in restoring knee functions in MLKI patients. Dr Joshi has discussed which grafts should be used in this particular issue. Allograft is preferred in cases with MLKI due to certain advantages, as its use is associated with decreased surgical time, decreased postoperative pain, reduced stiffness and graft site morbidity. However, it adds to the surgery cost in a limited resource setting and is not readily available.

Surgical Technique

The ideal surgical technique for managing MLKI is also a topic of disagreement amongst orthopaedic surgeons. This can be attributed to the availability of a wide variety of reconstruction techniques for addressing these injuries and an even wider number of possible permutations and combinations for combining these techniques. These are broadly divided into non-anatomical and anatomical approaches. Several studies prefer the latter, but more level-1 evidence confirming this notion is needed.

Some authors have emphasised the importance of ALL reconstruction and concomitant ACLR and demonstrated a decreased incidence of postoperative ALRI and graft failure [12, 13]. Such deductions may be extended to MLKI, but high-quality data is required to make those statements with certainty.

These injuries require multiple tunnel placements in the femur and tibia, and tunnel convergence is an issue that needs to be addressed as it leads to failure of the operative procedure in cases with MLKI.

There are exciting reads on using internal bracing in MLKI to improve the existing knowledge of surgical methods.

Dr. Moatshe has described some important pearls on optimum tunnel placement and techniques to avoid convergence in this particular issue. Dr Singhi also discussed an interesting tunnel-less technique for MCL augmentation in MLKI. These techniques will significantly expand the readers' knowledge and provide a perspective for future innovation.

Chronic MLKI

Treating chronic cases with MLKI is also essential in a holistic discussion of MLKI. These cases are to be assessed using long-leg films [14]. These lesions are conventionally managed using a two-staged procedure. In the first stage, the limb alignment is restored through an osteotomy, and the second stage is performed in only about 62% of patients with residual laxity. Only osteotomy alone may yield good clinical outcomes [15, 16] in the remainder of these patients. Dr Pardiwala has narrated these concepts in this special issue, which will delight the readers.

Where do we need to go?

With the advancement in biomedical research, the role of tissue engineering and stem cell therapy must be explored in multi-ligamentous injuries. This may help in graft regeneration and repair rather than the need for ligament reconstruction.

The footprints of various ligaments can be estimated preoperatively to aid in the anatomical reconstruction of the injured ligaments.

Bioengineering techniques like 3D printing, navigation, and robotics should be integrated to improve the efficiency of surgical methods. This may provide an individualistic approach to each knee, thus minimising the chances of tunnel malposition, convergence, and blowout. This, in turn, will decrease the chance of failure after surgery.

Guidelines/protocols based on high-quality research should guide the management of these injuries, which can help treating doctors improve the outcomes of patients with these injuries.

There is also a need for a comprehensively designed rehabilitation protocol that can be followed post-surgery.

How do we get there?

There can be integrated research, including by orthopaedists and biomedical engineers, to explore the realm of tissue engineering and stem cell therapy, which can aid in the regeneration of the injured ligaments, thus decreasing the need for reconstruction surgeries and manufacturing of ligaments for use in surgeries in the lab. This will mitigate the risks associated with the use of allografts and will provide all the benefits related to the use of allografts.

Surgeons can utilise preoperative radiographic tools like CT scans and MRI, which can aid in preoperative measurements of various ligament footprints and sizes if normal knee imaging is also available. Thus, they can help in an individualised anatomical reconstruction of the injured ligaments.

3D printing can be used for better preoperative planning and manufacturing patient-specific zigzags for tunnel placement, the precision of which can be enhanced by navigation and robotics.

Conducting prospective studies with respectable sample sizes at high-volume centres dedicated to sports injuries in India can generate high-quality research data required to ascertain more information on the topic. This could be possible with a sound referral system guiding such patients to tertiary care hospitals and facilities for data registration and maintenance of registries, which show the trends in the Indian population, which significantly varies morphologically from the Western population.

There is also a need for integrated workmanship between surgeons, sports injury physicians, and physiotherapists to formulate standardised rehabilitation protocols, which can be based on different scenarios at the patient's presentation, protocol-guided initial assessment, and type of operative procedure performed.

I congratulate all the authors and the editors for compiling such elaborate articles on this vital topic, making this special issue an essential read for all those dealing with these injuries.

Funding

None.

Data availability

Not applicable.

Declarations

Conflict of interest

The authors declare no conflict of interest related to this study.

Ethical Approval

Not Applicable.

Informed Consent

Not Applicable.