International panel presents novel strategies for managing sports injuries

“World-wide, we have seen an exponential growth in the number of individuals who participate in organized and recreational sports. Treatment algorithms for injuries are being constantly revised as we learn more about sports-related injuries,” said Pietro Tonino, MD, moderator of the symposium Current Trends in Sports Medicine: An International Perspective held at the AAOS Annual Meeting.

A distinguished international panel presented the latest preventive and nonsurgical treatment strategies for managing muscle strains, tendinopathy, and anterior instability of the shoulder, as well as a leading-edge regenerative medicine technique for articular cartilage injuries. Although not all these options are yet available to U.S. surgeons, they are a harbinger of treatments to come.

Managing muscle injuries
“Muscle injuries are one of the most frequent sports lesions,” said Jacques Menetrey, MD, of Geneva, Switzerland. “It is critical to provide the best mechanical and biologic environment to ensure rapid, complete healing and to prevent a second tear.”

The conservative treatment known as PRICE (Protection, Rest, Ice, Compression, Elevation) is a familiar method to promote initial healing. For 2 to 3 days (up to 5 days for more severe injuries), protection should include immobilization or the use of crutches.

According to Dr. Menetrey, this phase should be followed by controlled isometric, isotonic, and isokinetic contractions of the injured muscle group with increasing levels of intensity.

“Reconditioning the injured muscle group is mandatory,” he advised. “Return to play should be based on the athlete’s ability to stretch the injured muscle as much as the contralateral healthy muscle, pain-free use of the injured muscle in sports-specific movements, and comparable strength between injured and healthy muscles.”

Dr. Menetrey also discussed some novel treatments for muscle healing—such as the use of growth factors and cytokines—that are still being investigated in Europe and have not been approved by the U.S. Food and Drug Administration.

In addition to PRICE, hyperthermia is emerging as an effective treatment for some injuries. “Rapid, precise application of heat at the injured site improves and accelerates the healing process,” explained Dr. Menetrey. “It stimulates the muscle precursor cells and protein synthesis and increases the heat shock proteins.”

A Phase I clinical trial is now testing the efficacy of a device to deliver this hyperthermia application; preliminary results look “very promising.”

Managing tendinopathy
Tendinopathy accounts for a substantial proportion of overuse injuries in sports, according to Nicola Maffulli, MD, MS, PhD, of Staffordshire, England.

Dr. Maffulli then provided several examples of randomized controlled studies that he and his colleagues have conducted on both conservative and surgical methods.

A randomized, controlled, Level I, evidence-based trial compared the following three methods for managing chronic tendinopathy of the Achilles tendon: eccentric loading, repetitive low-energy shock-wave therapy (SWT), and a “wait-and-see” approach.¹

All 75 patients enrolled in the study had received more than 3 months of unsuccessful conservative management that included peritendinous local injections, nonsteroidal anti-inflammatory drugs, and physical therapy.

The first group was treated with eccentric loading, which consisted of doing two types of heel drops—one for the soleus and the other for the gastrocnemius. Patients started with 1 set of 10 repetitions on the first day, gradually increasing to 3 sets of 15 repetitions with 1-minute rests between sets, twice daily for 12 weeks.

If the patients did not experience pain in the Achilles tendon, they were encouraged to load the calf muscles with 5 kg of weight—increasing the weight in multiples of 5 kg until the third set of the eccentric exercises.

Group two received three sessions of SWT at weekly intervals. Using the handpiece that generates the actual shockwave, the physician treated the point of maximum pain first and then moved the handpiece in a circular motion around the area of tenderness. No anesthetic was used.

Based on the Likert scale, patients who were treated with eccentric loading and those who received low-energy SWT had comparable results. In the loading group, 60 percent of patients were assessed at grade 1(“completely recovered”) or grade 2 (“much improved”); 53 percent of the SWT group were similarly assessed.

No statistical difference was seen between the loading and SWT treatment groups (p = 0.259; power = 0.13) using the Victorian Institute of Sport Assessment (VISA-A).

Only 24 percent of the “wait-and-see” cohort, however, reported grade 1 or grade 2. In addition, 19 of the 25 patients in the “wait-and-see” group reported having to take naproxen or paracetamol for pain. “Wait-and-see is an ineffective treatment for chronic tendinopathy,” he reported.

A surgical study investigating the effectiveness of percutaneous longitudinal tenotomies for Achilles tendinopathy found that 37 of 52 middle- and long-distance runners reported excellent or good results at an average of 22 months postsurgery.

“This procedure is simple, can be performed on an outpatient basis with local anesthetic, and requires minimal follow-up care,” said Dr. Maffulli. “It is our operative treatment of choice for cases of chronic tendinitis when conservative treatment fails.”

Shoulder injuries
“Contact sports pose challenges for orthopaedic surgeons,” said Riccardo Minola, MD, of Milan, Italy, in part because the athletes want to return to play as quickly as possible.

To treat traumatic shoulder injuries, Dr. Minola advised, “Focus on the damage and always check both shoulders for laxity or instability.” Although radiographs may not be needed to make a diagnosis of shoulder instability, they may uncover other pathologies such as Hill-Sachs lesions, osseous Bankart lesions, or other traumatic shoulder injuries.

“If a dislocation has occurred, the literature supports primary surgery in young adults (usually male) who are engaged in highly demanding sports, but the evidence is limited,” said Dr. Minola. “For other categories of patients or injuries, there is no evidence available to determine whether surgical or nonsurgical treatment is better.”

Dr. Minola uses arthroscopic surgery for “first-time shoulder dislocations” in “high-demand overhead athletes” who require maximum flexibility and control, and open surgery for athletes who have chronic dislocations.

Cartilage defects
“Since 1996,” said Mitsuo Ochi, MD, PhD, of Hiroshima, Japan, “we have used tissue-engineered cartilage made ex vivo to treat osteochondral defects of the joint.”

Although tissue-engineered cartilage has a 93 percent rate of excellent and good outcomes in one study, it has only been indicated for focal cartilage defects. For larger osteochondral defects, bone marrow stimulation is preferred even though it does not always promote formation of hyaline cartilage.

“One possible reason is compressive overload on regenerated tissue in the drilled or microfractured area at an early stage,” said Dr. Ochi. “To reduce the overload, we developed an articulated distraction device (Fig. 1), which creates adequate joint space and maintains good range of motion.”

Another issue is the inadequate number of bone marrow mesenchymal stem cells (MSCs) to repair the cartilage defect. Cultured MSCs—injected into the knee joint—have been found to be effective in a rat model.

Combining the articulated distraction device with injection of the cultured MSCs “should be a new approach for large defects in the near future,” Dr. Ochi predicted.

Dr. Ochi believes that injecting cytokines or growth factors and cells is now the best possible method for treating articular cartilage defects.

“We have a completely novel approach for the future—a cell delivery system that utilizes an external magnetic field (EMF) (0.6 T),” he said, introducing his new concept for treating articular cartilage defects.

After bone marrow aspirate is collected and MSCs are cultured, the MSCs are mixed with magnetic beads. The MSC complex is then injected into the knee joint and the EMF is used to direct the MSC complex to the osteochondral defect in the knee joint—successfully repairing it (Fig. 2).²

According to Dr. Ochi, emerging technologies such as articulated distraction arthroplasty and magnetic bead delivery of MSCs could change future treatment strategies for articular cartilage injury in athletes.

Annie Hayashi is the senior science writer for AAOS Now. She can be reached at hayashi@aaos.org

References:

1. Rompe J, Nafe B, Furia J, et. al. Eccentric loading, shock-wave treatment, or a wait-and-see policy for tendinopathy of the main body of tendo achillis. Am J Sports Med. 2007;35:375-382.
2. Kobayashi T, Ochi M, Yanada S, et. al. A novel cell delivery system using magnetically labeled mesenchymal stem cells and an external magnetic device for clinical cartilage repair. Arthroscopy. 2008;24(1):69-76.