Stem Cell Therapy Following Meniscus Knee Surgery May Reduce Pain, Restore Meniscus

PR Newswire

First study of its kind found no “clinically important” safety issues with treatment

ROSEMONT, Ill., Jan. 16, 2014 /PRNewswire-USNewswire/ — A single stem cell injection following meniscus knee surgery may provide pain relief and aid in meniscus regrowth, according to a novel study appearing in the January issue of the Journal of Bone and Joint Surgery (JBJS).

More than one million knee arthroscopy procedures are performed each year in the U.S. primarily for the treatment of tears to the meniscus – the wedge-shaped pieces of cartilage that act as “shock absorbers” between the thighbone and shinbone in the knee joint.

In the first-of-its-kind study, “Adult Human Mesenchymal Stem Cells (MSC) Delivered via Intra-Articular Injection to the Knee, Following Partial Medial Meniscectomy,” most patients who received a single injection of adult stem cells following the surgical removal of all or part of a torn meniscus, reported a significant reduction in pain. Some patients─24 percent of one MSC group and 6 percent of another─experienced at least a 15 percent increase in meniscal volume at one year. There was no additional increase in meniscal volume at year two.

“The results demonstrated that high doses of mesenchymal stem cells can be safely delivered in a concentrated manner to a knee joint without abnormal tissue formation,” said lead study author C. Thomas Vangsness, Jr., MD. “No one has ever done that before.” In addition, “the patients with arthritis got strong improvement in pain” and some experienced meniscal regrowth.

Specific Study Details The study involved 55 patients, ages 18 to 60, who underwent a partial medial meniscectomy (the surgical removal of all or part of a torn meniscus) at seven medical institutions. Patients were randomly placed in one of three treatment groups: Group A patients (18) received a “low-dose” injection of 50 million stem cells within seven to 10 days after meniscus surgery; Group B patients (18), a higher dose of 100 million stem cells; and the “control group (19),” sodium hyaluronate only. Patients were assessed to evaluate safety, meniscus regeneration through MRI and X-ray images, overall condition of the knee joint and clinical outcomes through two years. While most of the patients had some arthritis, patients with severe (level three or four) arthritis, in the same compartment as the meniscectomy, were excluded from the study.

Key Study Findings

• There was no abnormal (ectopic) tissue formation or “clinically important” safety issues identified.
• There was “significantly increased meniscal volume,” determined by an MRI in 24 percent of the patients in the low-dose injection group (A) and six percent of the high-dose injection group (B) at one year. There was no statistical increase in meniscal volume at two years.
• No patients in the control group (non-MSC group) met the 15 percent threshold for increased meniscal volume.
• Patients with osteoarthritis experienced a reduction in pain in the stem cell treatment groups; there was no reduction in pain in the control (non-MSC group).

“The results of this study suggest that mesenchymal stem cells have the potential to improve the overall condition of the knee joint,” said Dr. Vangsness. “I am very excited and encouraged” by the results. With the success of a single injection, “it begs the question: What if we give a series of injections?”

Disclosure: None of the authors received payments or services, either directly or indirectly (i.e., via his or her institution), from a third party in support of any aspect of this work. One or more of the authors, or his or her institution, has had a financial relationship, in the thirty-six months prior to submission of this work, with an entity in the biomedical arena that could be perceived to influence or have the potential to influence what is written in this work. No author has had any other relationships, or has engaged in any other activities, that could be perceived to influence or have the potential to influence what is written in this work.

About the JBJS

The American Academy of Orthopaedic Surgeons (AAOS) has more information on meniscal tears and common knee injuries atwww.orthoinfo.org.

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SOURCE Journal of Bone and Joint Surgery

Orthopedic Center of Palm Beach County – In The News

Dr. Marc Matarazzo featured in the Spring 2012 Genex Magazine

Workers Compensation and Disability Management News

Hip Pain in the Injured Worker:

Impingement and Labral Tears

Marc F Matarazzo, MD

Director of Sports Medicine

Orthopedic Center of Palm Beach County

Sports Medicine Champion,  JFK Medical Center

Hip pain in the injured worker has often been unfairly dismissed as a muscle “strain” or “early arthritis”. 

However, with recent advances in the understanding of hip and its pathoanatomy, the differential diagnosis

has become quite broad. Hip pain in the active patient can be intra-articular, extra-articular, central pubic,

or referred pain. A thorough history and focused examination, combined with enhanced imaging tools,

can usually lead to a more precise diagnosis and a more successful treatment plan.  Femoroacetabular

impingement (FAI) of the hip is still a relatively unrecognized entity by many physicians, but has become

well known in the sports medicine arena. It occurs intra-articularly when there is abnormal contact between

the head/neck junction of the proximal femur and the rim of the acetabular socket.  This can lead to

acetabular labral tearing and chondral injuries, possibly resulting in early arthrosis of the hip joint.

Labral tears can occur independently with isolated trauma or in conjunction with FAI. There are

two main types of FAI — Cam impingement (on the femoral side) and Pincer impingement

(on the acetabular side), but more commonly ( 86%) a combination of the two exists.

Labral tears, chondral injuries, and loose bodies are typical findings associated with FAI and these

can also cause debilitating symptoms, particularly in the younger, active patient. Cam impingement

exists when an abnormal “bump” is found at the femoral head/neck junction or angular deformities of the

prox femur that create shear stresses at the chondrolabral complex with acetabular chondral injury and labral

tearing. Cam impingement is more common in the younger, active male. Pincer impingement is due to

abnormal overhang or “over coverage” of the acetabular rim that pinches the labrum between the rim and

the femoral head/neck, leading to degeneration of the labrum, chondral injury on the acetabular side of the

joint, and potential loose bodies.  This type is more common in middle-aged women and can be related to

developmental hip dysplasia. Symptoms of FAI and associated conditions include anterior groin pain,

“deep” hip pain, catching or pinching in the groin, lateral or posterior hip pain, pain with activity —

particularly with high hip flexion and internal rotation. Signs include a positive “impingement” test,

which is performed with the patient supine.  Flexing the hip while adducting and internally rotating will

reproduce symptoms.  Also, a decrease in the amount of internal rotation can be seen. The diagnosis

of FAI is made with a thorough history, physical examination, and diagnostic imaging including plain

radiography with specific views of the pelvis and hip, as well as MRI scanning with intra-articular contrast,

and diagnostic joint injections. Imaging findings can be rather subtle and often not reported, especially if the

radiologist is not familiar with FAI or is unaware of the symptoms of the patient and abnormalities being

sought. Initial treatment of FAI is conservative — stressing education and counseling, NSAIDs, activity

modification, and sometimes intra-articular corticosteroid injections.  However, because this condition

is caused by abnormal anatomy, surgery is often indicated in this patient population.  Surgical treatment

consists of open procedures, arthroscopic procedures, or a combination of the two.

Open procedures require fairly large incisions, more blood loss, and the need to dislocate the hip with

the risk of iatrogenic avascular necrosis (AVN) of the femoral head.  Arthroscopic procedures are

performed through a few portal incisions, utilizing a specialized traction table to distract the the femoral

head out of the acetabulum with little risk of AVN nor significant blood loss. Using either technique, the

goals are the same — to restore normal hip anatomy.  Pincer and Cam lesions are removed.  The labrum is

partially excised or repaired back to the acetabular rim, loose bodies are removed, and any articular

cartilage lesions are addressed with debarment or micro-fracture techniques.Recovery is variable

depending  on the extent of the injury and/or procedure performed, but return to play can be as early as 3

months, although 6 months is not uncommon. Hip pain in the athlete can be a challenging problem, but

with a more complete understanding of the hip, superior imaging modalities, and the evolution of hip

arthroscopy, we are much better able to recognize and treat a large array of injuries and

conditions about the hip –particularly in the younger, active patient.