DISEASES OF THE MUSCULOSKELETAL SYSTEM PART 2 Chapter 7 Pg: 126

TRAUMA: Ligament Injury – Anterior/Posterior Cruciate Ligament Rupture Anterior Cruciate Ligament (cranial cruciate ligament) and Posterior Cruciate Ligament --stabilize knee joint Ruptured CCL – most common stifle injury and leads to Degenerative Joint Disease (DJD) May be complete rupture or partial tear => unstable joint => DJD CCL is similar to a human that tore their ACL Degenerative joint disease: cartilage deteriorates, mainly in knees, hips, and spine. Any bone really. Approximately 50% of dogs with a torn CCL also experience a meniscal or meniscus injury. The meniscus is a c-shaped pad of cartilage in the knee that acts as a shock absorber Meniscal injury: Torn tissue in the knee. Remove the torn meniscus because it can be painful. MOST COMMON KNEE ISSUE SEEN. Degenerative joint disease: Also known as osteoarthritis (A type of arthritis that occurs when flexible tissue at the ends of bones wears down)

TRAUMA: CRUCIATE LIGAMENT INJURY/RUPTURE

CLINICAL SIGNS OF CRANIAL CRUCIATE LIGAMENT INJURY/RUPTURE Highly active, athletic animals Middle-aged obese dog

CLINICAL SIGNS OF CRANIAL CRUCIATE LIGAMENT INJURY/RUPTURE Joint effusion: excess synovial fluid in and around the knee. If recent tear, they can have effusion(swelling in the knee). Normally, it is an acute onset. Hyperextending: over extend leg. Animal is acutely non wt. bearing on the rear leg after hyperextending the stifle joint Joint effusion

TRAUMA: CRANIAL CRUCIATE LIGAMENT RUPTURE Cranial drawer: tibial slides forward. Tibial compression: tibia moves forward when the hock if flexed. Cranial drawer test Tibial compression test

Same as the tibial compression test: tibia moves forward when hock is flexed.

CRANIAL CRUCIATE LIGAMENT RUPTURE REPAIR Extraarticular: outside the joint Most successful in small patients (less than 30 lbs). Suture material is placed around the caudal fabellae ( behind femoral condyles) and through a tunnel in the tibial crest to stabilize the joint (front portion on this image). The tibial crest is the insertion point for the patellar tendon. Extraarticular Stabilization *Most successful in patients less than 15kg

CRANIAL CRUCIATE LIGAMENT RUPTURE REPAIR Intraarticular: within the joint Over-the-top patellar tendon graft: uses a strip of patellar tendon to replace the cranial cruciate ligament The patellar tendon attaches the bottom of the patella to the top of the tibia (Ligaments connect bone to bone) (Tendon connects muscle to bone) Intraarticular stabilization: Over-the-top patellar tendon graft

CRANIAL CRUCIATE LIGAMENT RUPTURE REPAIR This prevents the tibial from moving forward away from the femur. The surgeon actually cuts the tibia and rotates it backwards. This makes the tibia fit in place at a level where it does not rub the femur and then uses a plate and screws to hold it in the level position. When the cruciate ligament is ruptured, the knee feels unstable for the dog and causes them to become lame. This is done by having radiographs prior and the surgeon actually goes and measures the angle that she needs to cut the bone. Intraarticular stabilization technique TPLO – 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 

The tibia is pushed further back to prevent the tibia from slipping forward.

TPLO surgery (DOVE) 11 mins Medial buttress( tissue that has thickened or scarred due to trying heal itself)

CRANIAL CRUCIATE LIGAMENT RUPTURE – CLIENT INFO Restrict activity 3-4 weeks post surgery Cage rest Leash walk only to urinate and defecate Gradually increase exercise 4-8 wks post sx Full activity 8-12 weeks Opposite cruciate often tears within 1 yr Weight loss helps DJD of stifle joint is likely If no surgery, joint thickens from new fibrous tissue formation in an attempt to stabilize itself Can use Adequan injections to help with process. DJD (osteoarthritis) is likely because it is caused by inflammation and break down of cartilage and joints. Adequan helps relieve the pain of arthritis by soothing and lubricating the inflamed joint in addition to stimulating joint cartilage repair (will never be the same though)

LUXATING PATELLA These occur frequently in dogs and occasionally in cats. Medial luxation (most common) – mainly in small breeds (Both knees are affected, but surgeon will usually do surgery on the worst one) Lateral luxation (not common, usually do not do surgery for this)- in both small and large breeds (They will do surgery if it is bad enough)

LUXATING PATELLA Medial patella luxation is most common. Medial is usually congenital (anatomical deformities). Can lead to a CCL tear.

LUXATING PATELLA Grade 1: moves out of groove slightly and goes back Grade 2: Moves completely out of groove and goes back Grade 3: sits outside of groove naturally but can be pushed back in Grade 4: sits outside of groove and will not go back in The patella rests in a groove on top of the femur called the trochlear groove

POOR CONFORMATION: LUXATING PATELLA PATELLA IN GROOVE PATELLA OUT OF GROOVE With this image, you have to rotate limbs inwards to get a straight shot of the patella.

TREATMENT OF PATELLAR LUXATION Surgery to place patella back in place. Also known as a Trochleoplasty. (trochlear groove is reshaped to improve patellar stability) Cerclage wire is then used to strap the patella into place TROCHLEAR WEDGE RESECTION

TROCHLEAR WEDGE RESECTION Deepens the trochlear groove due to them cutting it.

Recovery will be similar to a Cranial cruciate ligament

HIP DYSPLASIA YOUNG DOGS 5-8m AND MATURE ANIMALS WITH CHRONIC DISEASE Rarely seen in dogs less than 30lb. YOUNG DOGS 5-8m AND MATURE ANIMALS WITH CHRONIC DISEASE

HIP YSPLASIA

HIP DYSPLASIA Can be genetic or trauma. It can be popped back into place by closed reduction (Reduction means putting bone back in place), but can pop back out. If that happens, surgery would be best. Poor conformation combined with genetic, environmental and nutritional factors

HIP DYSPLASIA PHYSICAL EXAM FINDINGS Pain on palpation of hips Joint laxity – subluxation of hip Crepitus Decreased range of motion of hip joints Atrophy of thigh muscles Crepitus: bone rubbing against bone. Atrophy due to limb not being used as much. Leg looks smaller and withered away.

Hip Dysplasia DIAGNOSTICS: Radiographic view ventrodorsal view of the pelvis with rear limbs extended symmetrically and rotated inward to center the patellae over the trochlear grooves Moving the hips inwards. This puts a lot on the patients hips, so it is best to take these images while under sedation. OFA- They also have to be 2 years of age. The obturator foramen is the large opening created by the ischium and pubis bones of the pelvis through which nerves and blood vessels pass For standard Orthopedic Foundation for Animals–type radiographs to evaluate hip conformation, extend the hips and internally rotate the tibias until the patella lies directly over the trochlear grooves. Be sure the pelvis is straight, with symmetric obturator foramina.

POOR CONFORMATION: HIP DYSPLASIA and OFA CERTIFICATION You want it to sit in the socket.

POOR CONFORMATION: HIP DYSPLASIA and OFA CERTIFICATION

HIP DYSPLASIA and OFA CERTIFICATION Dysplastic hips are categorized as mild, moderate, or severe

HIP DYSPLASIA TREATMENT: medical management NSAIDs Adequan helps relieve the pain of arthritis by soothing and lubricating the inflamed joint in addition to stimulating joint cartilage repair (will never be the same though) NEUTRICEUTICALS/CHONDROPROTECTIVE AGENTS

HIP DYSPLASIA TREATMENT: MEDICAL MANAGEMENT Polysulfated glycosaminoglycan (Adequan): Polysulfated glycosaminoglycans prevent cartilage breakdown by inhibiting the enzymes of cartilage degradation during inflammation. Cosequin: Cosequin is a brand name for glucosamine HCL combined with chondroitin sulfate which may stimulate synthesis of synovial fluid, inhibit degradation, and improve healing of articular cartilage. Can use Adequan injections for management. Cosequin stimulates synthesis of synovial fluid

Hip Dysplasia Treatment: surgical correction Total hip replacement Salvage procedure in mature dogs with severed DJD unresponsive to medical Tx Pain free and near normal limb function in 95% of cases Femoral Head Ostectomy Forms “false” joint Removal of femoral head to prevent joint pain Salvage procedure when medical treatment not working and other sx too expensive Best - < 20#; good musculature Abnormal gait Triple Pelvic Osteotomy Allows rotation of dorsal acetabular rim to increase coverage of femoral head Good return of function with minimal arthritic changes Total hips are a new procedure. If do it incorrect the femur can be split. Femoral head ostectomy most common. TPO: cuts into the pelvis so the socket (acetabulum) can be rotated over the femoral head. Used on larger breeds. “False joint” forms from scar/fibrous tissue

HIP DYSPLASIA TREATMENT: surgical correction TRIPLE PELVIC OSTEOTOMY It is stabilized by a bone plate.

HIP DYSPLASIA TREATMENT: SURGICAL CORRECTION FEMORAL HEAD OSTECTOMY “False joint” forms from scar/fibrous tissue

HIP DYSPLASIA TREATMENT: SURGICAL CORRECTION TOTAL HIP REPLACEMENT

Hip Dysplasia – Client Info Weight control important to decrease load on painful joint Swimming excellent activity Lameness may occur due to surgical shortening of the affected limb Physiotherapy – decreases joint stiffness, helps maintain muscle integrity Joint degeneration progressive May be heritable – do not breed Special diets designed for fast growing dogs may decrease severity