The triple tibial osteotomy is a surgical procedure used to treat dogs that have completely or partially ruptured the

cranial cruciate ligament The anterior cruciate ligament (ACL) is one of a pair of cruciate ligaments (the other being the posterior cruciate ligament) in the human knee. The two ligaments are called "cruciform" ligaments, as they are arranged in a crossed formation. In t ...

in one or both of their stifles. The cranial cruciate ligament connects the

femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femo ...

with the

tibia The tibia (; : tibiae or tibias), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two Leg bones, bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outsi ...

, which functions to stabilise the

canine Canine may refer to: Zoology and anatomy * Animals of the family Canidae, more specifically the subfamily Caninae, which includes dogs, wolves, foxes, jackals and coyotes ** ''Canis'', a genus that includes dogs, wolves, coyotes, and jackals ** Do ...

stifle joint The stifle joint (often simply stifle) is a complex joint in the hind limbs of quadruped mammals such as the sheep, horse or dog. It is the equivalent of the human knee and is often the largest synovial joint in the animal's body. The stifle join ...

from the forces put on it during exercise and weight bearing.

Stifle joint in dog

The stifle joint relies solely upon

soft tissue Soft tissue connective tissue, connects and surrounds or supports internal organs and bones, and includes muscle, tendons, ligaments, Adipose tissue, fat, fibrous tissue, Lymphatic vessel, lymph and blood vessels, fasciae, and synovial membranes.� ...

structures for its integrity; thus it differs from an elbow or a hip joint that have a lot of parallel joint surfaces and an interlocking structure to the joints that give them inherent stability and an almost vacuum effect that keeps the joint surfaces together. Along with the cranial cruciate ligament, the other soft tissue structures stabilising the stifle are the caudal cruciate ligament and the two menisci, all of which are intra-articular (within the joint), and the two collateral ligaments (external to the joint).

Muscle tone In physiology, medicine, and anatomy, muscle tone (residual muscle tension or tonus) is the continuous and passive partial contraction of the muscles, or the muscle's resistance to passive stretch during resting state.O’Sullivan, S. B. (2007) ...

through the

quadriceps The quadriceps femoris muscle (, also called the quadriceps extensor, quadriceps or quads) is a large muscle group that includes the four prevailing muscles on the front of the thigh. It is the sole extensor muscle of the knee, forming a large ...

hamstring A hamstring () is any one of the three posterior thigh muscles in human anatomy between the hip and the knee: from medial to lateral, the semimembranosus, semitendinosus and biceps femoris. Etymology The word " ham" is derived from the Old ...

and calf muscles play a significant role in the forces acting on the joint.

Cranial cruciate ligament

The cranial cruciate ligament is composed of two bands, a craniomedial band and a caudolateral band. It functions to stop cranial (anterior) movement of the tibia with respect to the femur,

hyperextension Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...

of the stifle joint and internal rotation of the tibia. The cranial cruciate ligament is thought to be able to resist a force equivalent to four times the weight of the dog before it ruptures, but often the ligament is weakened by

arthritis Arthritis is a general medical term used to describe a disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, Joint effusion, swelling, and decreased range of motion of ...

that is present in the joint. Arthritis infers inflammation of the joint; in this condition there is the production of a joint fluid that is less

viscous Viscosity is a measure of a fluid's rate-dependent resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for example, syrup h ...

and therefore less able to absorb shock than normal fluid. Joint fluid's other role is to provide nutrition to the cartilage and the cruciate ligaments. The situation is a little like a chicken-and-egg scenario: it is usually accepted that the cranial cruciate ligament ruptures because arthritis has caused the ligament to weaken because of poor joint fluid characteristics, but what causes the arthritis in the first place – a partial cruciate tear? The situation is dissimilar to that seen in human athletes where overextension of the joint stretches the cranial cruciate ligament to failure, and replacement of the ligament with a fascial prosthesis has a good prognosis for return to full function.

Menisci

The menisci are the other intra-articular structures that help to stabilise the joint and help to distribute load evenly across the surfaces; these are crescent-shaped discs of cartilage facing each other from side to side across the joint. They are thicker at the outside and with a thin inner aspect and they also have nerve fibres that help to tell the brain how much load is getting transmitted through the joint. The

medial Medial may refer to: Mathematics * Medial magma, a mathematical identity in algebra Geometry * Medial axis, in geometry the set of all points having more than one closest point on an object's boundary * Medial graph, another graph that repr ...

(inside) meniscus is often damaged with a long-standing cruciate ligament rupture because it is firmly attached to the tibia and gets crushed during abnormal cranial movement of the tibia. The

lateral Lateral is a geometric term of location which may also refer to: Biology and healthcare * Lateral (anatomy), a term of location meaning "towards the side" * Lateral cricoarytenoid muscle, an intrinsic muscle of the larynx * Lateral release ( ...

(outside) meniscus is more firmly attached to the femur and does not get crushed.

Surgical rationale

The triple tibial osteotomy was developed by a

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

veterinary Veterinary medicine is the branch of medicine that deals with the prevention, management, diagnosis, and treatment of disease, disorder, and injury in non-human animals. The scope of veterinary medicine is wide, covering all animal species, both ...

orthopaedic Orthopedic surgery or orthopedics ( alternative spelling orthopaedics) is the branch of surgery concerned with conditions involving the musculoskeletal system. Orthopedic surgeons use both surgical and nonsurgical means to treat musculoskeletal ...

specialist A specialist is someone who is an expert in, or devoted to, some specific branch of study or research. Specialist may also refer to: Occupations * Specialist (rank), military rank ** Specialist (Singapore) * Specialist officer, military rank in ...

, Dr. Warrick Bruce, while he was working in

Adelaide Adelaide ( , ; ) is the list of Australian capital cities, capital and most populous city of South Australia, as well as the list of cities in Australia by population, fifth-most populous city in Australia. The name "Adelaide" may refer to ei ...

South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...

. By changing the geometry of the forces of gravity and muscle contractions that act on the stifle during weight-bearing, it aims to neutralise the

shear force In solid mechanics, shearing forces are unaligned forces acting on one part of a Rigid body, body in a specific direction, and another part of the body in the opposite direction. When the forces are Collinearity, collinear (aligned with each ot ...

that causes the cranial movement of the tibia with respect to the femur. This shear force develops because the canine

tibial plateau Tibial may refer to: * Tibia bone * Tibial nerve * Anterior tibial artery * Posterior tibial artery * Anterior tibial vein * Posterior tibial vein The posterior tibial veins are veins of the leg in humans. They drain the posterior compartment ...

– the weight-bearing aspect of the joint – is sloped caudally (downwards towards the back of the joint) and there is an acute angle between the tibial plateau slope and the

patellar ligament The patellar tendon is the distal portion of the common tendon of the quadriceps femoris, which is continued from the patella to the tibial tuberosity. It is also sometimes called the patellar ligament as it forms a bone to bone connection when ...

. In the triple tibial osteotomy procedure, the tibia has three osteotomies (cuts into the bone with a bone saw) performed upon it with the aim of realigning the tibial plateau slope so that it ultimately becomes aligned at right angles to the patellar ligament instead of sloping backwards. By achieving this, shear forces within the joint are neutralised and the joint is stable as the dog weight-bears. The joint is not stable, however, when it is physically manipulated by attempting to move the tibia

cranially Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

. This contrasts with previous methods of cranial cruciate ligament repair which aimed to provide stability to the joint by replacing the ligament either with a fascial graft within the joint, or using a prosthesis made of nylon placed externally from the lateral

fabella The fabella is a small sesamoid bone found in some mammals embedded in the tendon of the lateral head of the gastrocnemius muscle behind the lateral condyle of the femur. It is an accessory bone, an anatomical variation present in 39% of human ...

to a hole drilled in the tibial crest. The triple tibial osteotomy has been developed as a hybrid of two previously available orthopaedic procedures, the

tibial tuberosity advancement Tibial tuberosity advancement (TTA) is an orthopedic procedure to repair deficient cranial cruciate ligaments in dogs. It has also been used in cats. This procedure was developed by Dr. Slobodan Tepic and Professor Pierre Montavon at the School ...

and the

tibial plateau leveling osteotomy TPLO, or tibial-plateau-leveling osteotomy, is a surgery performed on dogs to stabilize the stifle joint after ruptures of the cranial cruciate ligament (analogous to the anterior cruciate ligament CLin humans, and sometimes colloquially called ...

. The tibial tuberosity advancement neutralises shear force within the stifle by advancing the tibial tuberosity until the tibial plateau is at right angles to the patellar ligament. The tibial plateau leveling osteotomy neutralises shear force by rotating the tibial plateau so that it is approximately horizontal with respect to the long axis of the tibia. The triple tibial osteotomy combines both of these procedures and as such less radical changes than either are required.

Surgical technique

The triple tibial osteotomy involves removing a horizontal small wedge of bone (average 16 degrees) halfway along a vertical osteotomy in the tibial tuberosity. Firstly by removing the wedge of bone, the tibial plateau is levelled. Secondly as the horizontal defect created by removing the wedge is closed down, the tibial tuberosity is itself advanced by several millimetres. This compares with an average of 20 degrees plateau levelling required for the tibial plateau leveling osteotomy and 9-12mm of tibial tuberosity advancement with the tibial tuberosity advancement. Return to normal function is rapid, with most dogs having good use of the leg and a normal appearing gait within 3–4 months; long-term progression of arthritis is minimal.

Alternative procedures

* Tibial-plateau-leveling osteotomy *

Tibial tuberosity advancement Tibial tuberosity advancement (TTA) is an orthopedic procedure to repair deficient cranial cruciate ligaments in dogs. It has also been used in cats. This procedure was developed by Dr. Slobodan Tepic and Professor Pierre Montavon at the School ...

* Tightrope CCL * Simitri Stable in Stride * Cranial tibial wedge osteotomy

References

*Vet Comp Orthop Traumatol. 2007;20(3):159-68. {{DEFAULTSORT:Triple tibial osteotomy Veterinary procedures Dog health