If You Want Buns Of Steel ....

Ok I admit, that was a heading to get you to read this post. But seriously, I had a patient who was referred to our clinic by a GP across the road.  He hurt his groin while doing Brazilian jiu-jitsu 2 months ago and had not gotten better. He said his previous physiotherapist just got him to do clam shell exercises and it did not help at all. 

Want to know the best exercise for packing the biggest punch for the gluteal area? Let me share the results of the following study by Collings et al (2023).

Their study compared and ranked gluteal muscle forces in 8 hip focused exercises performed without and with external resistance, i.e. dumbbells or loaded barbell.

This 8 hip focused exercises in the study were single leg (S/L) squat, S/L Romanian deadlift (RDL), split squat, S/L hip thrust, banded side step, hip hike, side plank and side lying leg raise. The exercises were performed with and without weights for 12 reps max (RM)  and measured by electromyography (EMG). 

Analysis of muscle forces were limited to gluteus maximus (pictured above), medius and minimus (below). The results show that varying demands were placed on the individual gluteal muscles. Peak gluteal muscle forces significantly increased when all exercises were performed with weights compared with body weight alone. 

R gluteus medius and minimus

This is the first study to investigate a wide range of hip focused exercises that also includes isometric hip and hip abduction exercises. Clam shell exercises which you already know from my earlier  blog post is not great at activating gluteus medius and was not even included in this study. The S/L RDL and side plank  produced the highest peak gluteus medius and minimus muscle forces. 

Side plank

This is what I found most interesting. I was surprised that this variation of the side plank (pictured above) really targeted the gluteus medius and minimus too. It will be a good choice for physiotherapists to teach their patients this since no equipment is needed. Patients can easily do it at home or during on field/ court training.

Single leg RDL

We already know that the S/L RDL (pictured above) is good for  hamstrings strengthening. Done with weights, the S/L RDL activated high gluteus minimus force (100 percent observed) while gluteus maximus (98 percent) and gluteus medius (84 percent). S/L RDL is the go to exercise if you need to target all 3 gluteal muscles simultaneously along with the hamstrings.

To sum up, for the gluteus maximus, the split squat, S/L RDL and S/L hip thrust are the exercises that you want to do if that is what you want to train. The S/L RDL and side plank  produced the highest peak gluteus medius and minimus muscle forces. Those who are injured may start by doing the lower tier exercises and/ or reduce load (pictured above). You may want to remember this if your goal is to prevent injury, as part of rehabilitation or for performance.

Reference

Collings TJ, Bourne MN, Barrett RS et al (2023). Gluteal Muscle Forces During Hip-Focused Injury Prevention And Rehabilitation Exercises. Med Sci Sp Ex. 55(4): 650-660. DOI: 10.1249/MSS.0000000000003091

Bow Legged Or Knocked Knees? Or Normal?

Different knee shapes

Visual inspection of lower limb alignment is common standard practice for us in our clinics (and elsewhere I am sure) when a patient comes in with ankle, knee, hip and low back pain.

You would think that as a trained health professional, we would be able to see if a person has normal, bow legs (varus) or knocked knees (valgus) quite easily. If it was an extreme valgus or varus it would be fairly easy to differentiate. What if you saw the following pictures below?

Varus or valgus?

How about this? Confused?

Hence I was rather surprised when a published study (Nguyen et al, 2022) found that visual inspection of lower limb alignment is not valid nor reliable when compared to the gold standard of whole leg radiography (WLR).

The study involved 50 patients who underwent a WLR and a standardized digital photograph of the lower limbs (pictured below). The patient's feet were placed 10 cm apart and in 10 degrees of external rotation with knees in full extension and both arms alongside the body. Pictures were taken from knee height, 2 meters away from the patient. 

WLR and digital photograph

There were 4 assessors who rated the digital photograph twice. Two are orthopaedic surgeons with 10 and 5 years experience respectively. The remaining two were an orthopaedic resident and a researcher. They were unaware of the patients' hip knee angle (HKA).

Knees were rated with severe valgus (>5 degrees), moderate valgus (2-5 degrees), neutral, moderate varus (2-5 degrees) and severe varus (>5 degrees).

Ready for the results? The percentage of incorrect visual leg assessments ranged between 46-75 percent. Now that's high! The errors were lowest in patients with moderate valgus alignment (knock knees) and highest when the patient presented with a severe varus deformity (bow legs). See the picture below of a patient I saw recently. How can the error be highest when it is bow legged? Isn't that fairly obvious?

Surely this varus is obvious

There were patients with a neutral leg alignment but were assessed to be pathological in 50.7 percent of cases. I am concerned about this since the wrong diagnosis of normal presentation as pathological/ dysfunctional may potentially cause the patient to opt for surgical intervention. This will lead to increased health care cost for patients and insurers.

Interestingly, there were no significant differences between the accuracy of more experienced verus less experienced assessors.You would think that the ability to assess alignment would improve with practice through one's working life.

The results also show that there were gender influences. Women do present an increased risk for incorrect readings due to the difference in the angle of the thigh bone between men and women.

The authors concluded that visual assessment of lower limb alignment does not provide clinically relevant information. Physical examinations and X-ray assessments are advised.

Limitations for this study? My biggest gripe was that visual assessments were done on 2-dimensional (2D) digital photographs instead of in person assessment. It is definitely easier (and more accurate) to visually assess a patient than to look at a digital photograph. Only 1 assessor measured the HKA on the WLRs, so there is no comparison for inter-assessor reliability.

Hopefully our surgeons here in Singapore are better are visually assessing patients. They should also do whole leg x-rays and in clinic assessments. Make sure yours does.

We see many of these cases. Come see us in our clinics if you have any pain or discomfort. While we cannot alter the shape of your knees, we can definitely reduce or take away the symptoms.

Reference

Nguyen HC, Egmond N, De Visser HM et al (2022). Visual Inspection For Lower Limb Malalignment Diagnosis Is Unreliable. Cartilage. 13(4): 59-65. DOI: 10.1177/19476035221113952

Should You Strength Train On Unstable Surfaces?

On the BOSU ball

A patient come to our clinic this week injured after lifting weights on an unstable surface. The studio he went to had them do chest presses and flys with a glute bridge on a BOSU ball (knees bent, buttocks up and feet resting on BOSU ball). 

Indo board

I often use the BOSU ball, wobble board and/or  Indoboard (much later on - see end of article) when my patients require proprioceptive training to prep them before they return to sport. Also for those if they have lots of metalwork (pictured below) in the ankle after a fracture. I find that challenging my patients on unstable surfaces may enable them to rehab faster compared to stable surfaces when it is safe to do so.

Check out all the metal work in the leg

Other than working on their balance and proprioception (joint position sense), I get them to step on and off, lunge sideways, forward, backwards and sideways so they will be ready when the terrain that they are on are cambered or cobblestones (especially overseas).

However, I never use them while doing strength training. Turns out there is some research supporting that. I came across the following article to investigate if there are benefits or cross over effects of strength training on an unstable surface.

The following study evaluated subjects undergoing stable and unstable resistance training for muscle power. The subjects were randomly assigned into 2 groups. Each group performed resistance exercises under stable or unstable conditions 3 times a week for 8 weeks. 

Before and after 4 and 8 weeks of the training program, the subjects underwent squats and chest presses on either a stable surface or BOSU/ Swiss ball with increasing weights of up to 85 percent 1RM (rep max). 

There were significant improvements of mean power during chest presses on a Swiss ball at weights up to 60.7 percent 1RM after 4 and 8 weeks of raining on an unstable surface. Mean power also increased significantly during squats on a BOSU ball at weights up to 48.1 percent for 1RM after 4 weeks but not after 8 weeks of training on an unstable surface.

There were no significant changes in mean power during bench presses and squats on a stable surface after the same training. We do know from previous studies (Zemkova et al, 2014) that lower pre training values of power during resistance exercises on unstable surfaces are expected when compared to stable surfaces, especially at higher weights.

The researchers concluded that there is no cross over effect while weight training on unstable surfaces. Training has to be specific, if you want to get really strong and increase your 1RM max, you do not train on unstable surfaces since you cannot lift as heavy compared to on a stable surface.

Now you know, so you do not get hurt while trying something different that your gym suggests you do.

References

Zemkova E, Jelen M, Cepkova A et al (2021).There Is No Cross Effect Of Unstable Resistance Training On Power Produced During Stable Conditions. Appl Sci. 11(8): 3401. DOI: 10.3390/app11083401

Zemkova E, Jelen M, Kovacikva Z et al (2014). Weight Lifted And Countermovement Potentiation Of Power In The Concentric Phase Of Unstable And Traditional Resistance Exercises. J Appl Biomech 30: 213-220. DOI:10.1123/jab.2012-0229.

How's that for balance?

What Happens If You Have A Bone Bruise?

R knee bone bruise from Theinjurysource

A patient I saw recently had quite a big bone bruise on his tibia (shin bone) and femur (thigh) after tearing his ACL. They are also known as bone contusions. It is similar to a bruise you may get on your skin after a fall or when you bump into the corner of a table or chair. It can also be more serious than a bruise under your skin.

A bone bruise (or contusion) refers to blood that is trapped under the surface of your bone after an injury. Since bone is also living tissue, it can also get injured or bruised like your skin and muscles. It usually takes much more force to bruise your bone to injure it without breaking it. A bone bruise usually feels like a deep, dull and throbbing ache that's coming from deep inside the body.

We normally see bone bruises in our clinic after an acute ankle sprain or ACL tear. What's the implication of having a bone bruise? An article (Kia et al, 2020) looked at the incidence of changes on the articular cartilage surfaces on MRI five years after the ACL tear. Note that this is done without correlation with clinical and functional outcomes.

The authors found that the lateral (outside) tibia (shin bone) and femur (thigh) are more frequently involved. The area that was initially bruised sigificantly correlated with increasing chondral (articular cartilage) wear over time. The larger the bone bruise, the higher the chances of having a significant change in the articular cartilage 5 years post surgery.

Absence of a bone bruise on initial MRI was the greatest predictor of no cartilage wear at 5 years in all compartments of the knee. If there was a lateral meniscus injury, there was an increased risk of wear in the lateral tibial plateau (shin bone).

We do not know if this wear leads to pain or even the need for a joint replacement further down the road since the scans DO NOT always correspond with the patients' symptoms.

I always communicate this with the rest of my team seeing patients with bone bruises since this will affect and influence progression to activities of daily living and especially back to sport.

No one knows how long the bone bruises take to heal. In my case before I had the first of my 3 knee surgeries, the bone bruising was still seen on my repeat MRI 9 months later despite me not running or jumping while waiting for it to heal.

For the athletes, impact related activities should only be considered 16-20 weeks after surgery, especially running and plyometrics so as to decrease pain and swelling.

The patient needs to be progressed slowly to have long term success. Slower will always be better in these cases.

Reference

Kia C, Cavanaugh Z, Gillis E et al (2020). Size Of Initial Bone Bruise Predicts Future lateral Chondral Degeneration In ACL Injuries: A Radiographic Analysis. Orth J Sp Med. 2020: 8(5). DOI: 10.1177/2325967120916834.