Genetics and ACL Injuries in Women

Posted February 15, 2015 by Orthopaedic Specialists

ACL Injuries in Women – Do Genes Play a Role?

There has been a potential identification of the genes that may control the higher risk of the ACL injury in women compared to men. It is estimated that over 200,000 ACL injuries occur in United States every year.

There is a disproportionate number of non-contact injuries occurring in the female athlete compared to the male athlete. A non-contact ACL injury is the most common type of ACL tear mechanism.

Non-contact ACL injuries occur when an athlete tears their ACL without colliding or being tackled by another player. A common example of a non-contact ACL injury occurs when a basketball player is dribbling the ball down the court and stops and quickly changes direction. When the athlete stops and changes direction the knee gives way and the ACL tears.

Another example of a non-contact ACL tear is when a basketball player is jumping and lands. As the player lands, the knee gives way and the ACL tears. Some studies have reported a two to eightfold greater incidence of a non-contact ACL injury in the female athlete compared to male athletes playing the same sport. Why is this? What explains the higher rate of ACL injuries in women?

We do not know. There are many theories.

This is one of the hottest research areas in sports medicine. We know that an ACL injury can be devastating for any athlete. Return to the same level of pre-injury play following an acl injury is about 65% and the risk of early onset osteoarthritis involving the injured knee is 85%. We also know that the risk of re-tearing the ACL after surgery can be very high in the athlete who is under the age of 20 and returns back to a twisting, turning, jumping type sports such as soccer.

Researchers Look At Gene Expression To Understand ACL Injuries in Women

An excellent article published in the January 2015 American Journal of Bone Joint Surgery looked at comparing the gene expression in athletes with a non-contact ACL injury and comparing men and women.

The research team was led by Dr. Jeffrey Johnson from the University of Akron Ohio. The article title is: Gene Expression Differences Between Ruptured ACL’s in Young Males and Female Subjects .

The research team analyzed the DNA from ACLs that were resected at the time of surgery.

The different DNA patterns were separated via computer software. There were several statistical methods used to examine gender related differences. What the researchers found was very interesting. They found in the group of athletes that had a non-contact ACL injury, there was an up regulation (increased) in females compared to males of the gene ACAN (aggrecan) and FMOD (fibromodulin). They also found that WISP2 (WNT1 inducing signaling pathway protein 2) was down regulated (decreased).

Aggrecan is a proteoglycan molecule within the extracellular matrix of ligaments and many other musculoskeletal tissues. In other words, it is found in the makeup of ligaments. The ACL is the major stabilizing ligament in the knee joint. Aggrecan also plays a critical role in mediating chondrocyte and chondrocyte-matrix interactions: it helps to controls the basic cells that make up ligaments. It is also a major structural component of human cartilage and fibrocartilage. (more…)

Lower Back Pain

Posted February 9, 2015 by Orthopaedic Specialists

Does Your Lower Back Hurt? Learn Common Causes of Lower Back Pain and Lower Extremity Radiculopathy

Lower back pain can be caused by many different conditions including a herniated disc or sciatica. The Journal of the American Academy of Orthopaedic Surgeons recently published an excellent article on the common causes of lower back pain. This included lower back pain that radiates into the lower extremity. Dr. Bennett Douglas Grimm is the lead author of the Jan 2015 article. A summary of this very informative article is below.

Lower back pain that radiates into the leg is known as lumbar radiculopathy. The prevalence of true lumbar radiculopathy in the general population is approximately 3–5%. The two most common causes for these symptoms are a herniated disc or, less commonly, spinal stenosis.

A lumbar disc herniation most frequently occurs in patients younger than age 50. Symptoms of a herniated disc typically start with severe low back pain that will then radiate into the lower extremity. There may or may not be a traumatic or inciting event that causes the symptoms to start. Initially the low back pain occurs because a tear in the annulus surrounding the disc occurs.

The annulus is richly innervated by nerves which will cause severe pain when torn. After the annulus tears, disc material leaks out and compresses the nerve root going to the lower extremity causing leg pain. It is typically a two-step process. Some people hear or feel a pop at the time of injury which is the annulus tearing.

Once the nerve root is compressed, there may be symptoms of numbness, tingling and weakness involving the lower extremity. Symptoms usually worsen from sneezing or bending forward. Any action that increases intradiscal pressure will cause increased pain such as listed above.

The Physical Exam for Lower Back Pain

An important portion of the physical examination for low back pain is a positive nerve root tension test, also known as a straight leg raise test. This will be present 60% of the time in people who have disc herniation at L4-L5 and L5 and S1. A femoral stretch test may be positive for this condition at L2-3 and L3-4. There may be a decrease in reflexes at the patella tendon or Achilles’ tendon. The patellar tendon represents L4 and the Achilles tendon represents S1.

If there is bowel or bladder dysfunction, or saddle anesthesia is present, there is concern for cauda equina syndrome. This occurs with a very large disc herniation. This is a surgical emergency and requires urgent surgical decompression or permanent nerve damage can occur.

An MRI scan is the best imaging study for the above-mentioned diagnoses.

Spinal Stenosis and Lower Back Pain

Spinal stenosis is another common cause of low back pain and this typically occurs in patients older than 65. Spinal stenosis is caused from osteoarthritis involving the lumbar spine. Typically there is a history of chronic low back pain that radiates into the buttuck and legs.

With spinal stenosis, it is not as common to have only one leg affected, which is typically seen with the disc herniation. Only 20% of the people that present with spinal stenosis would have a positive straight leg raise test. People will complain of pain with ambulation. Their pain will typically stop when they bend forward or sit down. Plain X-rays and an MRI scan are used to help to diagnose this condition.

Additional Causes of Lower Back Pain

There are other causes of lower back pain that occur that have nothing to do with the anatomy of the back but can cause pain in that region of the body. This can be caused from other anatomical structures in the body that are near the low back such as the pelvis and the hip joint.

Conditions such as hip osteoarthritis, osteonecrosis, femoral acetabular impingement, femoral neck stress fractures, pelvic insufficiency fractures, trochanter bursitis of the hip, and sacroiliac joint pain can mimic low back pain. (more…)

A Bone Doctor Offers A Review of Bone

Posted January 30, 2015 by Orthopaedic Specialists

A Review of Bone from a Bone Doctor

What cells make up bone?

Bones are made up of the following types of cells: osteoclasts, osteoblasts and osteocytes

Where do osteoclasts, osteoblasts and osteocytes originate?

Osteoclasts, which are bone resorbing cells, come from the fusion of monocytes.
Osteoblasts, which are bone forming cells, come from bone marrow.
Osteocytes are the mature cells of bone that help to regulate the osteoclasts and osteoblasts.

Osteoclasts are found in something called resorption bays – these are indentations or pits along the surface of the bone. Certain hormones work to regulate osteoclasts. These include calcitonin which originates in the thyroid,and parathyroid hormone or PTH from the parathyroid gland.

Osteoblasts create a mineral from calcium and phosphate that forms into a durable, compact tissue. Osteoblasts are responsible for mineralizing most of the bone matrix. Active osteoblasts play an essential role in active bone formation. When bone synthesis is not actively occurring, osteoblasts are referred to as inactive.

Osteocytes make up greater than 95% of bone cells. They are encased in bone matrix. Bone matrix is a reservoir for many proteins including: collagen, osteocalcin, osteopontin, transforming growth factor and bone morphogenic protein.

Shaped like a star, osteocytes are generally located in mature bone. While the size of osteocytes varies, they are reported to have an average half life of about two and a half decades. (more…)

Total Hip Replacement (THA)

Posted January 22, 2015 by Orthopaedic Specialists

What’s New in Total Hip Replacement?

The Journal of Bone and Joint Surgery, September 2014 issue, published an article listing new research and interesting information regarding total hip replacements.

A Reduction in Transfusions
– Studies have found a significant reduction in the amount of blood transfusions after total hip replacement if IV tranexamic acid is used. This is a relatively inexpensive drug that is given intravenously to stop bleeding. It is an antifibrinolytic agent therefore it allows a more effective blood clot to form to prevent excessive bleeding during total hip replacement surgery.

Risk Factors for Pulmonary Embolism after Total Hip Replacement Surgery

Having had a previous pulmonary embolism
Chronic obstructive pulmonary disease
Atrial fibrillation
Anemia
Depression

Modifiable Risk Factors for Peri-Prosthetic Joint Infections

Obesity (46%)
Anemia (29%)
Malnutrition (26%)
Diabetes (20%)

Reduction of Joint Infections

Currently being studied in animal models: implants being coated with antibiotic impregnated microspheres. Early results have revealed an impressive 100% success rate in preventing infection in wounds that were contaminated with Staphylococcus aureus.

Fixation

Cementless fixation for Total Hip Replacement is recommended over the use of cement.

Dislocation

This is the most common reason for revision with total hip arthroplasty.

Surgical Care Improvement Project (SCIF)

This program was started in 2006 in an effort to decrease postoperative surgical site infection and venous thromboembolism (DVT/PE). After implementation of the surgical care improvement project, the rate of superficial surgical site infection did not change nor did the rate of pulmonary embolism decrease.

There was no clinical improvement, even though there was a high rate of compliance with the surgical care improvement project. (more…)

Femoroacetabular Impingement (FAI)

Posted January 8, 2015 by Orthopaedic Specialists

Is Prophylactic Surgery for Femoroacetabular Impingement Indicated? A Systematic Review.

One of the hottest topics right now orthopedic surgery is femoroacetabular impingement.

Femoroacetabular impingement (FAI) is a term used to describe a medical condition where a person’s hip bones are not shaped normally. This causes the hip bones to fit together irregularly so that the hip bones rub together, damaging the hip joint.

There are two types of FAI: pincer and the cam effect. FAI with the cam effect means that the femoral neck morphology has changed. FAI with pincer impingement is when there is overhang of the acetabulum abutting up against the femoral neck of the hip. The thought has been that these abnormal findings seen on x-rays lead to abnormal contact forces within the hip joint and can potentially cause hip osteoarthritis.

Researchers Ask Important Questions About Femoroacetabular Impingement

Medical researchers are still learning about femoroacetabular impingement. A review paper published in the December 2014 edition of the American Journal of Sports Medicine worked to answer three specific questions. The investigation was completed at New York University Hospital for Joint Disease in New York, New York. The lead author was Jason Andrew Collins M.D.

The authors wanted to answer the following three basic questions.

What is the prevalence of Femoroacetabular impingement (FAI) in the asymptomatic population?
Is there a correlation between morphological characteristics of femoraoacetabular impingment in the development of premature degenerative joint disease: hip osteoarthritis?
Will surgery to correct femoroacetabular impingement (FAI) prevent the development of osteoarthritis and subsequently prevent or delay the need for a total hip replacement?

Answers to Three Questions About Femoroacetabular Impingement

Answer #1. Femoroacetabular impingement is relatively common in asymptomatic patients, with prevalence rates ranging from 10 to 74%.

Answer #2. Early evidence suggests that arthroscopic treatment of symptomatic femoroacetabular impingement (FAI) can be beneficial to patients even beyond 50 years of age. The surgery can help improve pain and function if the patient’s hip patient is symptomatic. We cannot assure patients based on clinical evidence that surgical correction for femoroacetabular impingement, whether symptomatic or asymptomatic, will necessarily allow them to avoid osteoarthritis or future total hip replacement surgery.

It is also important to note that worse outcomes and a significantly higher failure rate have been shown, if surgery is performed in patients with a joint space loss greater than 2 mm. In other words if the arthritis is already fairly advanced, the prophylactic surgery will not help or delay the worsening of the hip osteoarthritis. (more…)

Septic Arthritis

Posted January 2, 2015 by Orthopaedic Specialists

New Test for Rapid Diagnosis of Septic Arthritis

There is a new and more accurate way to get a quick and inexpensive highly accurate test result on patients with septic arthritis, or a septic knee. The combined use of leukocyte esterase and glucose region strips can give a very quick and accurate diagnosis a septic arthritis.

This excellent study was published in the December issue of the Journal of Bone and Joint Surgery, American version, 2014. The research group was from the trauma department of the Hanover Medical School in Hanover, Germany. Mohamed Omar, M.D. was the lead author of the paper.

Leukocyte esterase is an enzyme secreted by neutrophils, and it is clearly increased in the inflammatory process. A reduce glucose concentration in the infected joint is also present because the bacteria will feed on the glucose. The combination of 1) identification of leukocyte esterase from the bacteria and 2) a reduced glucose level, strongly suggest an infected joint. It helps to quickly differentiate between the septic and aseptic inflammatory process in the joint in a real-time manner at a relatively inexpensive cost.

Prior to the findings in this study, the joint fluid would need to be sent to the microbiology lab and analyzed under the microscope to determine whether or not crystals are present within the joint fluid. This can take time, and results can vary depending on the staff available to read the slides in the microbiology lab.

This insightful study has recommended doing these two very simple inexpensive tests right in the doctor’s office or the emergency department to help differentiate between a septic arthritis and aseptic inflammatory process of the joint. It is still recommended that the joint be aspirated and fluid be sent for further analysis to the laboratory to obtain: 1) a Gram stain, 2) culture results, and 3) sensitivity results.

The combination of using the glucose strips and the leukocyte esterase test is a very quick screening test that can be completed in real-time fashion at a relatively low cost with accurate results.

The authors of the article pointed out that most healthcare providers would state that a synovial fluid count of greater than 50,000 cells per mm3 with a neutrophil percentage of greater than 75% is specific for septic arthritis. However others have reported that those cut off values failed to (more…)

Platelet Rich Plasma vs. Platelet Poor Plasma

Posted December 28, 2014 by Orthopaedic Specialists

Is platelet rich plasma (PRP) better than platelet poor plasma?

Current orthopaedic uses of platelet rich plasma or PRP include three major areas: 1) Acute muscle/ tendon injuries, for example, hamstring tears, 2) Chronic tendinitis, for example, tennis elbow, and 3) Intraoperative augmentation, for example, rotator cuff repairs.

There are numerous studies examining the effects of PRP but the type of PRP many times is not listed in the study. There are different formulas of PRP that are available.

An article published in the American Journal of Sports Medicine in May, 2014, examined leukocyte Rich PRP, leukocyte poor PRP versus platelet poor plasma. A research group out of Stanford University led by Hilary Braun found that when leukocyte poor plasma is injected into synovial cells they are better results and less death of the cells compared to when leukocyte rich plasma is injected into synovial cells.

The researchers concluded that clinicians should consider using leukocyte poor PRP as compared to platelet rich PRP.

It is important for future research to fully identify the type of PRP used in the different studies so apples can be compared to apples, so to speak. (more…)

Stress X-Rays and UCL Injury

Posted December 16, 2014 by Orthopaedic Specialists

Are stress X-rays of the elbow useful to determine if there is a UCL injury of the elbow?

– The ulnar collateral ligament (UCL) is one of the ligaments located on the inside of the elbow. The ulnar collateral ligament helps maintain the relationship between the bones in your forearm and arm.

For baseball and softball pitchers, the ulnar collateral ligament of the elbow provides stability to the elbow during the late cocking phase and early acceleration phase of pitching. The highest amount of force to the ligament occurs during pitching, when the elbow goes from flexion to rapid extension. It has been reported that every time a high velocity pitch is thrown, the UCL is placed at maximum tensile strength. Over time, with repetitive throwing, an injury to the elbow UCL can occur. The severity of a UCL injury may range from a partial thickness tear up to a full thickness tear.

Diagnostic testing to determine if a UCL injury is present has ranged from plain x-rays of the elbow, to stress x-rays, MRI without contrast and MRI with an arthrogram.

The gold standard to document that an ulnar collateral ligament injury is present on a stress x-ray is if an opening of greater than 3 mm is present medially. This increased distance or widening is a sign that a UCL injury is present.

A study published in the October 2014 Journal of Shoulder and Elbow Surgery authored by James R. Andrews M.D. and colleagues, compared patients that had surgical documentation of a complete tear of the ulnar collateral ligament. The researchers found that the stress x-rays obtained pre-operatively only revealed on average an opening of 0.6 mm compared to the healthy uninjured side. They found in athletes with a partial ulnar collateral ligament tear, stress x-rays of the elbow only opened up 0.1 mm.

They used a Telos stress device with 15 daN of pressure applied to the patients elbow prior to taking the film. After the Telos stress device was in place the x-ray was obtained. This allowed a standard and reproducible amount of force to be applied to each injured thrower’s elbow. (more…)

Achilles Tendon Rupture

Posted December 9, 2014 by Orthopaedic Specialists

What Gender is more likely to experience an Achilles Tendon Rupture?

When it comes to an Achilles tendon injury, men are more likely than women to tear their Achilles tendon. It is important to note, though, that the Achilles tendon rupture rate is increasing for both men and women.

The Achilles tendon is the biggest tendon in the body. It is made up of a strong band of tissue that serves to connect the calcaneus (or heel bone) to the muscles in the calf. This is why the Achilles tendon is sometimes referred to as the calcaneal tendon. You use your Achilles tendon when you walk, jump, run, twist and slide.

A study that examined the nationwide registry in Sweden determined that the Achilles tendon rupture rate increased between the years of 2001 and 2012. Thomas Huttunene M.D., PhD and colleagues published a descriptive epidemiological study regarding the incidence of Achilles tendon injury in Sweden in the October 2014 Journal of American Sports Medicine.

An acute Achilles tendon rupture usually occurs during participation in high impact sports such as basketball and tennis. The rate of occurrence peaks in the third and fourth decade of life. The reason behind an Achilles tendon rupture is unclear. There is some data that suggests that an Achilles tendon injury may be related to underlying degenerative changes of the tendon.

Since 2001, there has been a rise in the rupture rate overall for both men and women over age 18. There has been a 17% increase in the incidence of Achilles tendon injury in men between 2001 and 2012 and a 22% increase in the number of women experiencing an Achilles tendon rupture during this same period. (more…)

Rotator Cuff Tear Surgery

Posted December 7, 2014 by Orthopaedic Specialists

Massive Chronic Rotator Cuff Tear –

Researchers in Lyon, France, at the Santry Orthopaedic Center wanted to find out if certain rotator cuff tear patterns were associated with loss of range of motion. Philippe Collin M.D. and colleagues published a peer-reviewed article in the September 2014 Journal of Shoulder and Elbow Surgery specifically trying to identify rotator cuff tear patterns and whether they caused pseudoparalysis.

Pseudoparalysis is a condition secondary to rotator cuff pathology, where a person is unable to actively forward flex their arm. This can be a devastating condition for an individual.

Relationship Between Massive Chronic Rotator Cuff Tear Patterns and Loss of Active Range of Motion of the Shoulder

The research group looked at 100 individuals with massive rotator cuff tears. Individuals with fatty infiltration of Goutallier stage III were included in the study. The patients within divided into five groups on the basis of tear pattern. The five different groups involved a tear pattern of: 1) supraspinatus only, 2) superior subscapularis, 3) inferior subscapularis, 4) infraspinatus and 5) teres minor. They measured the patients active range of motion in each group.

Researchers found that active range of motion was significantly decreased in patients with three tear patterns involved. Pseudoparalysis was found in four out of five of the cases with a supraspinatus and complete subscapularis tear.

Pseudoparalysis was noted in only 45% of the cases involving a supraspinatus, infraspinatus and superior subscapularis tear. Loss of active external rotation was related to tears involving the infraspinatus and teres minor. Researchers found that the greatest loss of active internal rotation was related to tears involving the subscapularis.

Pseudoparalaysis and Mass Rotator Cuff Tear

Pseudoparalysis is a devastating condition for patients with rotator cuff pathology. This study revealed that if the entire subscapularis and supraspinatus tendon is torn, or three rotator cuff muscles are torn, then the patient is at risk for pseudoparalysis. (more…)