Isometric Contractions for In-Season Treatment of Patellar Tendinopathy


Guest blogger Dr. Napolitano grinding it out on the water.

One of the great features of modern medical journals like CJSM is the ability to publish studies ahead of print – we call it “Published Online First.”

With the flexibility  allowed by the internet and emerging media, we are able to get studies that have gone through peer review and are in the queue for printing out to the reading public months before they otherwise would see the light of day.

We have one of our “Published Online First” studies burning things up on emerging media.  At CJSM we follow the Altmetrics on the studies in our pages, and this new one — Isometric Contractions Are More Analgesic Than Isotonic Contractions for Patellar Tendon Pain: An In-Season Randomized Clinical Trial — currently has a very hot rating of 107 (and climbing).

The treatment of such a common condition will be of inherent interest to those who practice sports medicine. Moreover, managing this nagging condition in mid-season can prove to be a Sisyphean task for the athlete and clinician.  This study has great promise to make a significant impact on your care of the athletes you see.

I asked the physician fellow working with me at NCH sports medicine, Jonathan Napolitano, MD, to do a guest post on this study authored by Rio et al.  Dr. Napolitano’s commentary, forthwith:


Basketball season is upon us and our clinics have begun to fill with athletes ailing from patellar tendinopathy, seeking pain relief and a quick return to the hardwood.  As a sports medicine fellow with a residency background in physical medicine and rehabilitation I have used this time to step back and review the therapeutic exercises we prescribe for tendinopathies.  I have always paired the concept of eccentric strengthening with tendon repair.  However, various other types of muscle contraction and strengthening exercises can (and perhaps should be) prescribed as well.


In between isotonic beer curls at World Series 2017 game (L – R): Drs. Stephen Cuff, Reno Ravindran, Jonathan Napolitano

As an educational exercise I would like to take a moment to review the types of muscle contractions.  Isometric contraction occurs without any movement of the joint on which the muscle acts.  Isokinetic contraction occurs at a constant speed across a joint range of motion with variable resistance.  Finally, isotonic exercises are performed through normal joint range of motion with a consistent resistance at variable speed.  Isotonic contractions are further divided into concentric (muscle shortening) and eccentric (muscle lengthening).

Tendon pain is a factor that limits participation and performance in athletes.  Eccentric strengthening has shown good clinical outcomes in the long-term; however, this intervention can lead to increased pain in the short-term, and in 2005 Visnes et al showed eccentric strengthening to be of no benefit for in-season athletes.

Recent research by Dr. Rio et al [including senior author Dr. Jill Cook] compared rehabilitation programs for in-season athletes with patellar tendon pain.  Read more of this post


Tip-off: The NBA Season is Set to Begin!


“Kobe Bryant 61 NYK3,” by C.J. Iuzer.

The NBA regular season begins in a week, but there has been a lot happening already on the sports medicine front in the league.

From Paul George’s tib/fib fracture  to Kevin Durant’s ‘Jones fracture’  to Anthony Davis’ ‘wrist sprain,’  the athletic trainers, sideline physicians, and orthopaedic surgeons have had a busy ‘off season.’

And then, there is the question of Kobe.  He has been in the press a lot!

The NY Times recently had an interesting chat with the Kobe and Arianna Huffington, a unique friendship to say the least.  It seems Kobe is indeed looking at his future, however many seasons he may have in front of him.  And before he has even taken a shot in the regular season, pundits aplenty have shared their skepticism about his ability to perform on the court:  seems like a lot of folks are betting Kobe will be an albatross around the neck of the Lakers.

As most readers would know, Kobe Bryant ruptured his Achilles tendon at the end of the 2013 season. We blogged about it at the time (I’m reblogging the original post below) and discussed the pros/cons of operative vs. non-operative treatment of such injuries.  The issues of managing Achilles tendon pathology find their way frequently into the pages of CJSM.  Two such articles I would especially commend to the readers as being particularly relevant to the question of Kobe’s ability to recover:   “Complications after surgery or non-operative treatment for acute Achilles tendon rupture,”  and “Does accelerated functional rehabilitation after surgery improve outcomes in patients with acute Achilles tendon ruptures?”

Kobe, of course, went through operative treatment and an accelerated rehab.  His 2014 season was cut short because of a knee injury.  For the brief time he played, it would seem his Achilles held up quite well.  I suspect his knee injury was of the sort we saw after the NBA lockout, where a prolonged layoff from the sport can lead to higher rates of injury; that is, I think his knee injury was more linked to a prolonged absence from high-level running and jumping related to his prolonged recovery from Achilles tendon surgery.  A similar process was involved in Derek Jeter’s case, where a quick return from one injury (ankle fracture) led to a season-ending issue in another body part (quad strain).

I wouldn’t bet against Kobe, no sir.  He is as tough as they come, and throughout his career he has been at the forefront of athletes employing cutting-edge concepts in training and recovery.   I don’t know about the Lakers as a unit.  But I think Kobe can make some headlines that are not related to injury this season.  Draining 61 points at Madison Square Garden one more time in his career?  I think the Black Mamba may just have it in him.

Clinical Journal of Sport Medicine Blog

Image Kobe Bryant

I woke up this morning to hear very sad news that occurred in the NBA last night:  Kobe Bryant has ruptured his Achilles tendon.

Kobe, who turns 35 this year, is one of the most recognized athletes in the world (maybe one of the few things that China and the USA can agree on). He had been leading his team to crucial victories as they were making a playoff run when he succumbed to this not uncommon injury in the middle aged athlete. 

As he is quoted saying, he made a move he had executed a ‘million times’ when he felt like someone had kicked him in the leg, and he subsequently crumpled to the ground.  This is the classic history one might obtain when caring for an athlete with such an injury.  If you watch the video, you’ll see Kobe perform a classic…

View original post 380 more words

Nadal’s Knees


Rafael Nadal, invincible on clay, just might be beaten by this man in table tennis (Portuguese Table Tennis Coach Afonso Vilela)

What a great week it has been at the French Open in Paris.  As I write, I see that Serena Williams has just closed out Maria Sharapova in straight sets to regain the title she last held 11 years ago in 2002.  The men’s final is set for tomorrow, with the incomparable Rafael Nadal facing his Spanish countryman David Ferrer after outlasting Novak Djokovic in an epic five-set semi-final match.

Like many of this blog’s readers, I have been amazed and entertained by men’s tennis over the last decade.  It truly is a golden era for the sport, with Federer and Nadal and Djokovic and Murray each seeming to outdo the other in feats of tennis heroics.  Just yesterday Nadal made an amazing between the legs shot in the fifth set, but is that perhaps outdone by the amazing forehand Djoko ripped off Federer to save match point in the 2011 U.S. Open (going on then to win the semi-final)?

Read more of this post

PRP – magic bullet, or damp squib?

I’m guessing that not many of you will have seen the Academy Award-nominated biographical movie ‘Dr Ehrlich’s Magic Bullet’ starring Edward G Robinson. It outlines part of the career of the famous German scientist  Dr Paul Ehrlich, who popularised the concept of the ‘magic bullet’ therapy for the treatment of specific diseases. The film focuses on arsphenamine, ‘compound 606,’ and Ehrlich’s cure for syphylis.

The concept of the ‘magic bullet’ is rather older however, dating back at least to the 1800’s and deriving from the histochemical staining of tissues. It was Ehrlich’s opinion that, if a chemical could be found that targeted a pathogen, then a toxin could be delivered along with that chemical and hence a ‘magic bullet’ would be created that would destroy the pathogen leading to the elimination of a disease state. The concept was later realised following the discovery of monoclonal antibodies for which Köhler, Milstein and Jerne shared a Nobel Prize in 1984.

So-called ‘targeted therapies’ do not necessarily destroy their target as such, but may act to cause some form of modification, for example to a cell membrane via second messenger cascades or within the cell nucleus itself, leading to alterations in cellular genetic expression which then lead to a sequence of events that ultimately results in healing or an improvement in clinical symptoms.

Platelet-rich plasma (PRP) has been perhaps the most widely investigated preparation of late. PRP contains a number of growth factors including PDGF, IL-8, and CTGF, which have a number of different effects on different cells. Many of these actions are poorly understood, despite much basic science research, yet this has not prevented the clinical application of PRP for tendinopathies which is perhaps not surprising given the search for effective therapies for tendinopathies and the drive for ‘cutting-edge’ therapies in Sports Medicine.

However, when one stops to consider the knowledge gaps we have concerning the pathophysiology of tendinopathies, and our lack of understanding of the complex interactions involved in cellular healing mechanisms, then perhaps one may not be surprised to see the heterogeneity of results from clinical trials using PRP in the treatment of these conditions. The three main theories for the genesis of tendinopathy, namely overuse, overload and thermal stress, are still open to debate and there is a very wide range of possible actions of PRP on tendinopathic tendons.

Well-conducted clinical trials such as this one by de Jong et al on PRP for achilles tendinopathy, and systematic reviews such as this one by de Vos and colleagues ,have failed to find a positive clinical effect when using PRP use for the treatment of tendinopathies.

In this month’s systematic review in CJSM on the use of PRP in Sports Medicine as a new treatment for tendon and ligament injuries, Taylor and colleagues concluded that, despite several possible theoretical advantages to the use of PRP, there are very few well-conducted prospective studies and clinical trials available with which to inform clinical practice.

The recent IOC consensus paper on the use of PRP in sports medicine published in BJSM also highlighted the limited amount of basic science research, the paucity of well-conducted clinical studies on PRP, and the heterogeneity of methodological issues between different studies making comparisons of clinical effects difficult to judge. The IOC group’s recommendation was that clinicans should proceed with caution in the clinical use of PRP.

The debate is on as to whether there is a true lack of efficacy of PRP in the treatment of tendinopathies, or whether we simply need more well-designed clinical research.

What do you think? Where do we need to focus our research efforts? Should we forget the idea of ‘targeted therapies’ such as PRP and ‘magic bullets’ for tendinopathies?

CJSM would like to hear your views.

Leave a Comment

Leave a Comment

%d bloggers like this: