Lower Extremity: Knee
Anterior Cruciate Ligament Tears/Sprains:
Epidemiology: ACL injury is more common in female athletes than male athletes with an incidence ratio of 4.5:1. Neuromuscular control and landing biomechanics seem to play the largest role. Genetics, smaller notches, smaller ligaments, valgus leg alignment and smaller ligaments play a smaller role.
Anatomy: The ACL provides 85% of the stability of the knee in regards to anterior translation of the tibia in relationship to the femur. The ACL has two bundles which include the Anteromedial bundle and the posterolateral bundle. The strength of the ACL is measured at 2200 N. The hemearthrosis that occurs with an ACL tear results from damage to the Middle Geniculate artery.
Presentation: Patients commonly report feeling a “pop” in the knee associated with a deep knee pain and almost immediate swelling. ACL injury is typically a non-contact injury that is described as a twisting decelerating mechanism. This swelling is blood in the knee joint called a hemearthrosis. Physical examination is positive for effusion, Lachman test, Pivot Shift test, and Leilee’s Test.
Imaging: Plain x-rays do not typically show any injury. Rarely a Segond fracture may be seen which is pathognomonic from an ACL tear. The gold standard test for diagnosis an ACL tear is a MRI. Typical presentation would be an ACL tear, bone bruising of the Middle 1/3 of the Lateral Femoral Condyle and posterior 1.3 of the lateral Tibial Plateau. Lateral meniscus tears are seen in up to 50% of acute ACL tears at the time of MRI.
Treatment: NonOperative Management consists of formal PT, ACL substituting bracing, and activity modification. This may be a viable option for someone who has low physical demands or is willing to give up on some cutting, pivoting, twisting activities. The risk of meniscal damage increases with non operative management. Operative Management is considered for younger, more active patients. In my practice, I do not let age determine who is a surgical candidate. A candid conversation about the goals of the patient is most important. There are multiple types of reconstruction for ACL tears. The two basic reconstructions are Autograft (your own tissue) and Allograft (donor tissue). Current sources of Autograft include: hamstring tendons, patellar tendon, and quadriceps tendon. I currently favor the All-Inside Quadriceps Tendon ACL Reconstruction. Allograft options include Achilles tendon, Hamstring tendons, patellar tendon, and quadriceps tendon. Allograft reconstructions are considered in patients older than 30 years as the recovery and return to work is quicker. This is due to the lack of donor site morbidity. A very thoughtful conversation with the surgeon is important to pick the type of graft to use for the reconstruction. Considerations for return to sport, return to work, risk of recurrence, and possible complications should be discussed in detail. Pediatric patients have their own special considerations. Preoperative rehabilitation is important in getting the knee prepared for a surgical procedure. Typically patients will wait 1 month from injury to reconstruction. The rationale behind this is to allow the Acute Inflammatory Phase to resolve. This included the elimination of swelling, improvement in Range Of Motion, and strengthening the quadriceps muscle. After the surgical procedure, formal PT begins within days. The formal PT and Home Exercise Program lasts for 6-9 months. Return to sport is not recommended for 6-9 months depending on the graft type used and the progress of the therapy.
There are many known complications for this procedure. Some of them include: tunnel malposition, inadequate graft fixation, infection, arthrofibrosis, patellar tendon rupture, Complex Regional Pain Syndrome, patella fracture, hardware failure, tunnel osteolysis, late arthritis, Cyclops lesion, and re-rupture of graft.
Posterior Cruciate Ligament Sprain/Tears:
Epidemiology: Injuries to the PCL account for 5-20% of all ligamentous knee injuries.
Pathophysiology: The main mechanism is a direct blow to the tibia with the knee flexed 90 degrees such as in a car accident when a knee hits the Dashboard. Non-contact mechanisms include a knee hyperextension injury or a hyperflexed knee with the foot plantar flexed.
Pathoanatomy: The PCL is the primary restraint of posterior translation of the tibia in relationship to the femur. It prevents hyperflexion of the knee. Patients have the greatest degree of instability with the knee flexed at 90 degrees with isolated PCL injuries. PCL injuries are classified as Grade I, Grade II, or Grade III. Grade I tear is a partial tear with up to 5mm of posterior tibial translation. Grade II is 6-10mm of posterior tibial translation with the anterior tibia being flush with the femoral condyles. Grade III has greater than 10mm of posterior tibial translation. The tibia is posterior to the femoral condyles and can indicate a PCL and PLC injury.
Presentation: Patients must be differentiated between high or low energy mechanisms. A dashboard injury sustained in a car crash is high energy and can result in knee dislocation and possible neurologic injury. A low energy mechanism would be from a hyperflexion athletic injury with a plantar flexed foot. Patients complain of posterior knee pain and occasional instability. Physical examination can show a posterior sag sign. The most accurate test is the Posterior Drawer test. The Quadriceps Active test and Dial Test should be performed.
Imaging: Plain x-rays should be obtained to rule out fracture and to evaluate for subluxation or dislocation. MRI is the gold standard test for knee ligament injury.
Treatment: NonOperative Management consists of protected weight bearing and Physical Therapy. PCL specific bracing is available. Return to sports is 2-4 weeks with Grade I and Grade II injury. In Grade III injuries, relative immobilization in extension for 1 month with limited daily ROM exercises. PT should focus on quadriceps strengthening. Operative Management is reserved for multi-ligamentous injuries, Grade II and III with bony avulsion, or chronic Grade III with functional instability. Operative Management is performed as a primary repair in the avulsion injury or a reconstruction using autograft or allograft.
Epidemiology: Tears of the medial or lateral meniscus are the most common indication for knee surgery performed by Orthopaedic Surgeons in the United States. Medial meniscus tears are more common than lateral meniscus tears. The exception to this rule is in the setting of ACL tears where lateral meniscus is more commonly affected. Degenerative tears seen in older patients occur frequently in the posterior horn of the medial meniscus.
Anatomy: The function of the meniscus is to optimize force transmission across the knee. The way this is accomplished is by increasing congruency and shock absorption. The meniscus can transmit up to 50% of forces during weight bearing in extension and 85% during flexion. The meniscus adds stability to the knee. The posterior horn of the medial meniscus is the main secondary stabilizer to anterior translation of the tibia in relationship to the femur. This means that once the ACL is torn, then the medial meniscus becomes the primary stabilizer of anterior translation of the tibia in relationship to the femur. The meniscus is described as being a C-shaped piece of cartilage with a triangular cross section with the widest part being on the periphery. The meniscus is made up of 90% of Type I cartilage. There are 2 types of fibers in the ultra structure. There are radial fibers and longitudinal (circumferential) fibers which help to dissipate hoop stresses. The fibers form an interlacing network which expand under compressive forces and increase the contact area of the joint. This mechanism allows the knee to function with less overall knee Joint Reaction Forces.
Presentation: Meniscus tears typically present with medial or lateral joint line pain. Patients can complain of mechanical locking and clicking sides. Swelling may or may not be present. On physical examination, the presence of joint line tenderness is the most sensitive PE test and the McMurray’s test is the most specific PE test.
Imaging: Plain x-rays are not typically positive but remain part of the examination to rule out any other knee pathology. This is more important when someone presents with trauma to the knee. MRI is the gold standard test for evaluating the knee. More recently a new MRI machine has come to the Austin area. ARA has a 3Tesla MRI machine which can give you 9 times the image quality of the community standard 1.5 Tesla MRI machine.
Treatment: The most important thing I tell my patients about meniscal pathology is that not every meniscus tear needs a surgical procedure. Only symptomatic meniscus tears require surgery. NonOperative Management consists of initial period of rest, NSAIDs, and rehab (formal PT and transition to HEP). I typically inject the knee with steroid and give a 6 weeks trail period to evaluate how patients will respond. If they fail non-operative management, then we discuss Operative Management. Arthroscopic partial meniscus debridement is the most common procedure performed for meniscus tears. Meniscus Repair is much less common because of the limited number of patients who are candidates. Criteria include: younger age, peripheral tear, vertical and longitudinal tear, 1-4 cm in length and acute repair combined with ACL reconstruction. Meniscal transplantation is an option but has its specific set of limitations and is performed by few orthopaedic surgeons across the country. This procedure is best performed by high-volume physicians in the university settings.
Epidemiology: Acute traumatic patellar dislocations and subluxations occur equally by gender. Chronic patellar malalignment is more common in females. Patellar instability occurs most commonly in the teens and twenties. Some patients have predispositions such as Ehlers-Danlos syndrome, previous dislocation, or the Miserable Malalignment Syndrome (femoral anteversion, genu valgum, and external tibial torsion). Patella Alta or a high riding patella will have less patellar constraint as the patella does not articulate with the distal femoral sulcus.
Anatomy: The Medial Patellofemoral Ligament (MPFL) is the primary restraint in the first 20 degrees of knee flexion. As the knee flexes, the bony structures of the patellar femoral joint account for the stability. The Vastus Medialis provides a dynamic stabilizer. I think of the Vastus Medialis as a bridle on a horse forcing the patella to go where it is pulled.
Presentation: In the acute setting, patients rarely present with a dislocated patella. They typically self-reduce when patients extend the knee. A large hemearthrosis is typically seen. Patients will complain of pain on the medial side of the knee over the MPFL. On examination, patients will have increased lateral translation of the patella. On attempt of lateral translation, patients may have apprehension and will guard against lateral translation.
Imaging: Plain x-rays are taken to look for fracture, loose body, and to see if there is patella alta or patella baja. Lateral patellar tilt can be evaluated with the sunrise or merchant view. CT scan is best used for boney evaluation and can help with structural anatomy of the femur and patella. This can be used preoperatively for planning of what type of osteotomy might need to be performed. MRI is helpful for evaluation of tears of the MPFL or loose body. Bone bruise pattern may help with the diagnosis in conjunction with a MPFL tear and hemearthrosis.
Treatment: Non Operative Management consists of NSAIDs, activity modification, physical therapy and possible acute bracing. Strengthening of the Quadriceps and, in particular, the VMO is important. Closed chain quadriceps exercises are important. Aspiration of the hemearthrosis may provide some immediate relief if there is a tense effusion. Operative Management is typically aimed at the pathology which is present. If there is a loose body, then an arthroscopic loose body removal is a consideration. If the MPFL is torn, then a MPFL reconstruction can be performed. If there is lateral patellar tilt, then a lateral patellar retinacular release can be performed. If there is malalignment, then a Fulkerson osteotomy with medialization of the tibial tubercle can be considered. In patients who have a Q angle which is less than 18 degrees, then a Vastus Medialis Obliqus Advancement with or without a lateral release is a consideration.
Osgood Schlatter’s Disease:
Epidemiology: This is a traction apophysitis of the proximal tibia. It affects boys more commonly than girls. Boys are groups are typically 12-15 yrs old. Girls are 8-12 years old. It can be found bilaterally in up to 30% of patients. Athletes who perform jumping type exercise are at greatest risk (Basketball, Volleyball, and Sprinters). This is a self-limiting diagnosis but it does not resolve until growth at the proximal tibia has finished.
Anatomy: An apophysitis is a growth plate under tension. Girl mature skeletally before boys and hence the younger age of presentation and resolution.
Presentation: Patients will report a “bump on the knee” which is painful with activity especially running and jumping. Physical examination consists of palpation of the tibial tubercle and resisted leg extension with the patient seated and the knee flexed at 90 degrees.
Imaging: Plain x-rays will show an enlarged tibial tubercle and possibly fragmentation of the tibial tubercle. MRI is not typically used for this diagnosis as it is commonly made by history, physical and plain x-rays.
Treatment: NonOperative Management is rest, ice, NSAIDs, activity modification, Cho-Pat strap, and quadriceps/hamstring stretches. The vast majority of patients will outgrow this entity in 1 year. For patients who do not want to wait for 1 year, then a trail of Prolotherapy can be used to alleviate symptoms. Operative Management is reserved for patients who are skeletally mature with persistent pain over a patellar tendon ossicle.
Epidemiology: This entity occurs in up to 20% of jumping athletes. It is also known as “Jumper’s Knee”. Risk factors include tight hamstrings and quadriceps.
Pathophysiology: This is a degenerative rather than inflammatory entity. Micro tears of the tendinous tissue can occur secondary to repetitive, forceful, eccentric contractions of the extensor mechanism.
Presentation: Patients complain of pain at the inferior border of the patella which initially follows activity but can progress to pain during activity or with prolonged flexion.
Physical Examination: There can be swelling over the origin or insertion of the patellar tendon. There is commonly pain with palpation of the inferior pole of the patella with the leg in full extension and the quadriceps relaxed.
Imaging: Plain x-rays will typically be negative but there may be an ossicle in the tendon at the origin or the insertion. MRI can be helpful with diagnosis of the degree of tendonopathy versus partial tears.
Treatment: NonOperative Management consists of rest, ice, activity modification, and formal physical therapy. Stretching of the quadriceps and hamstrings is helpful. A patellar tendon strap such as the Cho-Pat strap can reduce symptoms. Cortisone injections into the tendon are discouraged secondary to risk of tendon rupture. Prolotherapy can alleviate the symptoms and treat the underlying issue of tendonopathy by causing micro trauma and stimulating the healing angioneogenisis cascade. This typically is a once a month procedure with a recovery period of approximately 6 months. Operative Management consists of arthroscopic debridement and stimulation of the distal pole of the patella. This can be done in an open manner whereby the surgeon excises the degenerated tendon and then repairs the remaining tissue. If the ossicle in the tendon is causing the pain, then the ossicle can be excised.
Medial Collateral Ligament Sprain/Tear:
Epidemiology: The most commonly injured ligament of the knee. It is both a primary and secondary valgus stabilizer of the knee. The injury typically occurs with a direct blow to the lateral side of the knee. The MCL is frequently seen in conjunction with ACL tears. Up to 5% of isolated MCL tears are seen with meniscal tears. Tears off the femoral side have better outcomes than tears off the tibial side.
Anatomy: MCL sprains are broken down into Grades of Tear: I, II, and III. Grade I is of mild severity without loss of ligamentous integrity and minimaly torn fibers. Grade II is of moderate severity with incomplete tearing of the MCL. There is joint laxity with an endpoint found with valgus stress of the knee bent to 30 degrees. MCL fibers remain apposed. Grade III is the most severe. There is complete disruption of the ligament. There is gross laxity with valgus testing of the knee and no endpoint is felt.
Presentation: Patient typically report hearing or feeling a “pop” at the time of injury. They complain of medial knee pain and feelings of instability with ambulation. Physical examination is positive for pain along the course of the MCL and occasional bruising and effusion. Valgus stress test with the knee bent at 30 degrees isolates the MCL. If there is laxity with valgus stress test in full extension then this may indicate a tear of the Posterior Medial Capsule or the cruciate ligaments. A complete and thorough ligamentous examination must be performed to identify additional injuries.
Imaging: Plain x-rays are recommended to rule out fracture. With gross laxity, joint space widening may be appreciated. MRI is the test of choice to identify ligamentous injury in the knee.
Treatment: NonOperative Management consists of bracing, Tylenol, rest and Physical Therapy. Return to play is approximately 1 week for Grade I injuries, 2-4 weeks for Grade II injuries, and 4-8 weeks for Grade III injuries. As was previously mentioned, proximal MCL tears have greater healing potential than distal MCL tears. Operative Management is typically reserved for Grade III injuries or in the setting of the Multi-Ligament Knee Injury. Distal ligament avulsion tears with the Stener Type lesion are known to have a high rate of healing with laxity and are good candidates for acute repair. In the setting of delayed presentation or laxity despite non operative management, then a delayed reconstruction can be considered. Operative management consists of acute repair or delayed reconstruction.
Lateral Collateral Ligament Sprain/Tear:
Epidemiology: This is a rare ligament to injure in isolation. It accounts for 7-16% when combined with lateral ligamentous complex injuries (Posterior Lateral Corner). The mechanism of injury is a excessive varus stress to the weight bearing knee.. External tibial rotation and hyperextension can also be associated with this injury.
Anatomy: The LCL is a tubular cordlike structure that originates on the lateral femoral epicondyle and inserts on the fibular head. It can easily be palpated on the lateral side of the knee when the knee is placed in a Figure of 4 position. The LCL is the primary restraints to varus stress of the knee in full extension and at 30 degrees of flexion. It is the secondary restraint to varus stress of the knee past 50 degrees of flexion. Similar to the MCL sprains, LCL sprains are classified as Grade I, Grade II, and Grade III. Grade I is a minimal tear. Grade II is a partial tear. Grade III is a complete tear.
Presentation: Patients complain of instability of the knee in extension and with cutting or pivoting activities. They may have difficulty with stairs.
Diagnosis: On physical examination, they will have pain along the course of the LCL. There maybe be lateral joint line bruising or swelling. A hemearthrosis is not typically seen. Varus opening of the knee in full extension is an isolated LCL injury; however, varus instability at full extension and at 30 degrees of flexion indicates a more severe injury. The LCL and Posterior Lateral Corner and/or Posterior Cruciate Ligament. The Dial Test can help to determine severity of injury.
Imaging: Plain X-rays are recommended to evaluate for possible fracture or joint line opening. Stress x-rays can be obtained but are painful for the patient. Once again, MRI is the gold standard for determining the presence and extent of a tear.
Treatment: NonOperative Management consists of bracing, progressive Range of Motion, and Physical Therapy. Return to sport is typically 4-8 weeks depending on the severity of the initial injury. Operative Management is reserved for Grade III tears and instability of the Posterior Lateral Corner. In the Acute Setting, LCL can be primarily repaired. If the LCL is part of a Posterior Lateral Rotational Instability picture, then reconstruction with allograft material may be needed to address all the injured structures.
There are many fractures that can occur in the region of the “KNEE”. The knee consists of the distal femur, the patella, and the proximal tibia. Any combination can be fractured. The fractures can be treated in one of several general manners depending on the severity of the fracture. The general types of NonOperative fracture treatments consist of splinting, bracing, or casting. Operative management consists of rods, plates and screws, or rarely external fixators. Depending on the location of the fracture, the surgeon will discuss different surgical options.
Tibial Eminence Fracture:
Epidemiology: This is a rare fracture that is essentially an avulsion of the ACL from its insertion with a small piece of bone attached from the proximal tibia. This is an ACL tear equivalent in the pediatric population. It is most common in the 8-14 yo age group.
Anatomy: The tibial eminience is the non articular portion of the tibia between the medial and lateral tibial plateaus. This is the area that the ACL inserts onto the tibia. There are 3 types of tibial eminence fractures: Type I is a displaced fracture, Type II is a minimally displaced fracture with an intact posterior hinge, and type III is a completely displaced fracture of the tibial eminence.
Presentation: Patients complain of knee pain and swelling. Patients will typically report not being able to fully straighten their knee. On physical examination, a large hemearthrosis is visible and palpable. Range of Motion is significantly limited. A lachman test is positive, and a McMurry for meniscal pathology is occasionaly positive.
Imaging: Plain x-rays can be helpful to see the tibail eminence avulsion fragment. This is a case where a CT scan can help to make a pre-operative. A MRI is typically obtained to evaluate the other soft tissues in and about the knee which include the menesci and ligamentous structures.
Treatment: NonOperative Management consists of aspiration of the knee to remove the hemearthrosis and provide some comfort. In a Type I and some Type II, an attempt at closed redustion and immobilization in full extension. Operative Management consists of arthroscopic fixation methods in an irreducible Type II or a Type III fracture. If this fails, then an open reduction and internal fixation can be performed. The biggest complication associated with this procedure is stiffness which is known as Arthrofibrosis. Damage to the growth plate can cause a growth plate arrest. Laxity of the ACL with feelings of instability can occur in up to 20% of non operative knees and 10% of operative knees.
Epidemiology: This is the most common bursitis of the knee. It is located just anterior to the patella and can become inflamed with excessive kneeling and friction. This is a common entity for wrestlers and must be monitored that it does not become a septic bursitis (this is an infection of the inflammed bursae).
Anatomy: The Prepatellar Bursae is a potential space that functions to facilitate the gliding of tissue over the patella.
Presentation: Patients will give a history of excessive kneeling will subsequent swelling of the knee. They will occasionally report pain when they kneel down onto a bed to get to sleep at night. It will look like a golfball under the skin. If there is significant warmth, redness, and enduration, this may be a septic bursitis.
Diagnosis: Physical examination is the mainstay of obtaining the diagnosis. The more difficult issue may be to distinguish between prepatellar bursitis and septic prepatellar bursitis. The aforementioned warth, erythema, and enduration can help but aspirating the bursae and sending the fluid to the lab for gram staining and cultures is very important.
Treatment: NonOperative Management consists of compression, NSAIDs, aspiration, and avoidance of kneeling. Antibiotics for septic bursitis is occasionally needed. Operative Management is rare but may be necessary in patients with long-standing swelling in the aseptic situation. Occasionally, a septic bursitis becomes severe and will require excision of the infected bursae and Irrigation and Debridement with admission to the hospital and IV antibiotics.
Patellar Tendon Rupture:
Epidemiology: The incidence of patellar tendon rupture is very low at approximately 0.5% of the US population per year. Males > Females are affected with the most common age group between the 20s-30s. Risk factors include some systemic medical conditions such as Lupus, Rheumatoid Arthritis, Diabetes, and chronic kidney disease. Localized issues include patellar degeneration or previous injury. Caution must be used with steroid injection INTO the tendon to treat a patellar tendonitis as this may cause localized weakness and predispose to a rupture.
Pathophysiology: The most common locaiton of the rupture is at the inferior pole of the patella but can be a midsubstance or distal avulsion from the tibial tubercle. The mechanism is from a tensile overload of the extensor mechanism with the knee in a flexed position. Most ruptures occur with a setting of tendon degeneration or long-standing tendonopathy.
Presentation: Patients will give a history of sudden quadriceps contration with the knee in a flexed position then feeling pain, hearing a pop, and having difficulty with weight bearing. On physical examiation, the patients will have a palpable gap in the patellar tendon, a high riding patella, and the inability of the patient to extend the knee when seated at the end of a table and the knee is flexed at 90 degrees.
Diagnosis: Plain x-rays will demonstrate a relative increase of the height of the patella. MRI is a great test to evaluate the severity of the rupture by distinguishing between the partial tear and complete tear.
Treatment: NonOperative Management is reserved for partial tears. This includes immobilization in full extension with progressive weight bearing. Operative Management is for partial tears that failed non-operative management and for complete ruptures. Primary repair can be performed with transosseous repair or delayed reconstruction with allograft tissue. The reconstruction can be from delayed presentation or rupture with the resulting tendon damage too severe to repair.
Quadriceps Tendon Rupture:
Epidemiology: Quadriceps tendon rupture is more common than patellar tendon ruptures. This occurs in patients 40yo and older with Males > Females being affected. The location is typically at the insertion of the tendon onto the patella. Similar systemic risk factors as the patellar tendon rupture.
Pathophysiology: The mechanism is an eccentric loading of the knee extensor mechanism. This means that the quadriceps is contracting while actually lengthening. It occurs when the foot is planted and the knee has a slight bend.
Presentation: Patients will report previous pain in the region of the superior pole of the patella which indicates possible previous tendonopathy. On physical examination, there may be pain at the site of the rupture or even a possible palpable gap. Patients will be unable to straighten the knee against resistance and unable to perform a Straight Leg Raise.
Imaging: Plain x-rays will either show patella baja or be negative. MRI will show the degree of tear and can help to differentiate between operative and non-operative treatment options.
Treatment: NonOperative Management is reserved for partial tears and consists of straight leg immobilization. Operative Management is primary repair of the tendon through transosseous tunnels. In the situation of a chronic tear or delayed presentation, an allograft reconstruction can be considered.
Epidemiology: The most common location is the posterior medial tibia. This accounts for upwards of 15% of running injuries and 60% of leg pain syndromes. Runners who run on hard surfaces, run more than 20 miles a week, or who run with overpronation and increased internal tibial rotation can experience this entity. This is very common just after the New Year Resolution population begins to exercise after a period of relative inactivity. This is common around the summer Two-a-Days of football where kids are getting off the sofa and beginning to do a significant amount of exercise.
Pathophysiology: Shin splints are caused by traction on the periosteum on the bone called Traction Periostitis. The tibialis anterior can be the culprit with traciton of the tibia and interosseous membrane. The Tibialis Posterior and Soleus can cause this entity with traction on the tibia. In females>males, this can progress into a stress fracture of the tibia.
Presentation: Patients will complain of a vague pain at the mid to distal tibia that decreases after the early stages of running. On physical examination, patients will have pain at the posterior medial border of the distal 1/3 of the tibia.
Imaging: Plain x-rays can be obtained to rule out stress fracture. In a patient with negative xrays and persistent pain despite rest, stretching and icing, a MRI can be obtained.
Treatment: NonOperative Management consists of activity modification, stretching, icing, and NSAIDs. Shoe modification and custom orthotics can be considered. Physical Therapy is a useful modality. Operative Management is very rare but can be discussed in the setting of failed non-operative treatment. Release of the deep, posterior compartment from the tibia can be considered but will likely not resolve all the complaints.
Epidemiology: The incidence of knee arthritis is 240 per 100,000 per year. It is approximately 3 times more common than hip arthritis. Females are more commonly affected than males with the rate increasing with age. Risk factors include: obesity, trauma, hard labor, and muscle weakness.
Pathophysiology: There is damage to the articular cartilage, inflammatory changes to the synovium and capsule, and bone cysts may form in late stages.
Presentation: Patients complain of knee pain, stiffness and swelling. On physical examination, there is decreased range of motion, effusion, and malalignment. Some patients are “bow legged” and some patients “knock kneed”. Many patients describe “start up pain”. This is a situation that occurs when you have been seated for a prolonged period of time, then you stand up and attempt walking. There will be significant pain for the first several steps that will lessen as you walk further. The pain will be tolerable until you sit down again for an extended period of time.
Diagnosis: Weight bearing plain x-rays are an excellent for discovering joint space narrowing. The recommended views are 20-degree bent knee PA, Sunrise, and Lateral. Physicians are looking for joint space narrowing, osteophytes, bone eburnation, subchondral sclerosis and subchondral cysts. It is rare to require CT scan or MRI for diagnosis of arthritis; however, in some instances, CT scan or MRI can be used in preoperative planning.
Treatment: NonOperative Management consists of things that most patients have heard before such as diet and exercise but some things they might not be aware of at this point. They are encouraged to ice after activities. NSAIDs are encouraged as a first line of treatment if bleeding ulcers or any other contraindications are not present. Weight loss in patients with a BMI of 25 or greater. Home Exercise Program and occasionally formal Physical Therapy is beneficial. Medial or Lateral Unloader braces can be beneficial in the right patients. Steroid injections can alleviate symptoms for a period of time but must be used judiciously. There is another type of injection which is called Viscosupplementation. Some patients know this as the “Roster Comb Shots”. Viscosupplementation injections occur once a week for a total of 5 weeks. There are many commercially available products such as Supartz, Euflexxa, Orthovisc, Hyalgan, and Synvisc to name a few. If these methods do not alleviate symptoms to a level that is acceptable, then more invasive methods can be considered. Operative Management may be indicated for a symptomatic degenerative meniscus tear. There is no good evidence that a “clean up scope” will provide any lasting relief of symptoms. High Tibial Osteotomy is a consideration in younger patients but may make Total Knee Arthroplasty more difficult in the future. Unicompartmental Arthroplasty is a procedure whereby a surgeon will replace one compartment of the knee instead of all three joint compartments. Finally, Total Knee Arthroplasty which is more commonly referred to as “Artificial Knee”. This procedure is indicated for patients with advanced degenerative changes in the knee that NonOperative management has failed to relieve pain in a meaningful and lasting way.