Case study: “Bulls Eye Lesion”

Every now and then in clinic you come across an injury that doesn’t quite fit “the norm” in terms of its recovery and management. I know every injury should be considered unique and every individual managed differently, but I thought I would share the management of this particular injury as it did prove tricky, we did fail a couple of times but eventually we got it just right.



This case study revolves around an 18 year old central midfielder, skeletally mature (no increase in height throughout the year / evident secondary sexual features) with a regular playing and training history prior to this injury. The presentation started in the autumn, after a complete pre-season and a good few weeks of competitive season underway. The player was in & out of training with a niggling groin / quad but with nothing substantial showing in assessment (the benefit of hindsight would be a very good money earner for any clinician that could harness it and set up a course!)

Towards the end of an under 21 game, the player was visibly struggling with pain at the top of his thigh, unable to sprint or strike a ball but 3 subs had been made, so he was inevitably staying on the pitch. At the end of the game, there was pain on palpation of the proximal rectus femoris and sartorious region. At this stage, there was nothing more to assess – there was no point, we would only aggravate something without actually learning too much more.  He presented the next morning with visible swelling in a small pocket of proximal thigh, palpable crepitus and pain with straight leg raise at 20 degrees.


Review of anatomy

The rectus femoris is a long fusiform muscle with TWO proximal attachments. The Direct Head attaches to the AIIS and Indirect Head attaches to the superior ace tabular ridge and the joint capsule. It has a long musculotendinous junction, as such can execute high velocity shortening as well as coping with significant length changes – remember it is a two joint muscle crossing both the hip and knee, with an action like kicking it must cope with hip extension coupled with knee extension during the pull-back of the kick, so both ends of the muscle are undergoing an eccentric load (Figure 1). The muscle structure itself is made up of mostly type II fibres so this high eccentric load makes the muscle quite prone to injury (Mendiguchia et al 2013 source).

Figure 1: Demonstrating the demands on rectus femoris during a kick


“Bulls eye lesion”

The term “Bulls eye lesion” was coined by Hughes (1995 source) following the presentation of injury on MRI (Figure 2). The high signal signs around the tear of proximal injuries. Occasionally this causes a pseudocyst, thought to be the serous fluid in the haematoma.

Figure 2: MRI scans highlighting a “Bulls-eye lesion” presentation

Predisposing factors to a proximal tear include fatigue, insufficient warm up and previous injury. From this case, we know that the pain started at the end of the game with the player in a fatigued state, and there was a history of niggling pain on and off for a couple of weeks.



The initial management of this injury was relatively routine, revolving around the POLICE guidelines (see Cryotherapy Blog). By day 2/3 we were addressing pelvic control exercises & posterior chain assessments. By day 5 we could achieve pain free stretching of the hip flexors and were using “Compex” to achieve isometric contractions of the quad while the player did upper body exercises.  After day 7 we were able to begin loading through a pain free range, working on co-contractions and concentric contractions of the quad.

To Speed up, you must be able to slow down – Bill Knowles

In the early-mid stages of rehab, we began working on movement patterns but at a painfully slow speed. Using the Bill Knowles mantra above, we progressed though different ranges of box step ups at slow pace to elicit a co-contraction of quads, hamstring and glutes (Figure 3). We slowly lowered the player through a Bulgarian split squat (Figure 4) to work on stability through range and we did some bridging variations (anti-rotational core) to encourage isometric control of the pelvis (Figure 5 – excuse the size 11 shoes taking up most of the picture!!).

Figure 6: a) Low box step up with knee drive
Figure 3: a) Low box step up with knee drive



Figure 6: b) medium box step up
Figure 3: b) medium box step up
Figure 6: c) High box step up
Figure 3: c) High box step up












Figure4: Bulgarian split squat (a & b) with progressive knee drive added later (c)
Figure4: Bulgarian split squat (a & b) with progressive knee drive added later (c)




Figure 5: Single leg bridge (a) with ipsilateral arm fall out (b) and contralateral arm fall out (c)
Figure 5: Single leg bridge (a) with ipsilateral arm fall out (b) and contralateral arm fall out (c)


By adding speed to the high box step up, we were able to switch the demand of the quadriceps to an eccentric action as the hip extends from a flexed position and the pelvis rapidly comes forward. We felt confident adding this eccentric component after we had cleared the player at a decent weight using the cable machine and a jacket to work though some deceleration work on the hip and knee (Figure 6).


Figure 6: Cable decelerations. a) start position b) end position with 3 sec hold. c to e) Dead slow step backs with weighted cable pulling posteriorly


The Bulgarian split squat was advanced by adding a knee drive at the top the squat, taking the back leg from a position of full hip extension through into hip flexion, a rapid concentric action. Following the model of exercise progression and regression (source) we added weight, removed the concentric component and decreased the speed again before building back up in a now weighted position.

The later stage of rehabilitation saw the player undertake more field based conditioning, working under fatigue whilst completing technical drills and building up his range of passing and shooting, all the while maintaining his gym program to supplement his rehab. This late stage rehab combined the expertise of the physiotherapy department, working alongside the strength and conditioning coach to discuss reps and sets of all drills and help periodise the weeks for the player and design the field based conditioning sessions; the sports science department was able to use GPS for all outdoor drills to help monitor load and provide up to date feedback on key information, in this case monitoring the accelerations and decelerations for the player in a fatigued state.

It was important that the stress elicited in this late stage was in line with the rest of the squad mid-competition. Rob Swire and Stijn Vandenbroucke (source) explain the importance of rehab being harder than the team training. This is because we have control over rehab, but no control of training so we must be confident that player won’t break down again in training!

The player returned just under 8 weeks later. He continued his gym program for another 4 weeks after his return to training and (touch wood) has had no recurrence of this injury since.



Knowing what I know now, I would be more cautious of this nondescript pain around the proximal thigh. The indirect head runs quite deep and typically presents as a gradual onset. The niggle the player was displaying a few weeks before was probably a worsening of this small tear, that when fatigued and put under a double eccentric load such as kicking or sprinting, was bound to “give” at some point.

I’m sure that reading this back, it seems pretty obvious that there was something wrong with the player initially. Again, another lesson learnt from this relates to the players age. He had not had a soft tissue injury prior to this, so his subjective history was vague and typically teenager-ish. Its important to remember that young players and professionals don’t necessarily understand their own body. If they play things down, its important that we as clinicians double check everything before we clear them and not just rely on their feedback alone.


I hope you find my reflections useful


Yours in sport



Don’t clam up over lower limb exercises



I regularly find myself debating this exercise with students, new staff, and part-time staff all from different clinical backgrounds and I always find myself asking them – “Why is that patient doing clams?”

For those unsure of the terminology, the “Clam” exercise is designed to activate the external rotators of the hip, performed in side lying with limited pelvic / lumbar rotation.

Firstly I’d like to make it clear that this exercise does have a place in some rehab plans and I am not adverse to including it as part of a program where necessary – but I strongly disagree with it being a mainstay in rehabilitation plans. Purely going from anecdotal evidence, people seem to use clams as a way of increasing endurance of the glutes, particularly glute med. Often prescribing high sets and reps to target the endurance component of the muscles. Previous literature has suggested that Maximum Voluntary Contraction (MVC) of greater the 50% is required to produce any strength gains in an individual muscle (Atha 1981). Figure 1 below demonstrates the EMG activation of glute med during 2 clam exercises, at 30 and 60 degrees hip flexion. Its clear from this study that the activation of glute med is below the required level to achieve any strength gains.

Glute med (if it ever did work in isolation, which I don’t think it does) would concentrically abduct the hip, isometrically stabilise the pelvis and lower limb, and eccentrically control adduction and internal rotation. The best types of activity to stimulate these actions are going to be weight bearing exercises (Figure 1); (Krause et al 2009).

There is evidence to suggest that the posterior portion of glute med is deactivated with any degree of hip flexion, with the bias for primary movement coming from gluteus maximus (Delp et al 1999). This said, Di Stefano et al’s (2009) study produced similar glute med activation at 30 and 60 degrees hip flexion. Either way, my argument is the same – clams probably aren’t working the structures you intend to target.

Reference: DiStefano 2009 here

Clinical Reasoning

My question to clinicians who regularly use clams is always “why?”. What is the purpose of this exercise? At the moment, I work with an elite athletic population. How often in their training and/or competition do they have to externally rotate a flexed hip in an open chain from a side lying position? Never. Even in standing, I can only think of them opening up their hip to control a ball in mid-air but then they are mainly using hip flexors to activate that movement – something we strictly instruct them not to do with a clam. So now that we can’t think of a transferable example for this exercise, I would ask “why are we doing high reps and sets of an exercise we don’t need to do?”

Problem solving

We have already said that the best exercises for glute med activation are weight bearing exercises and the reason for that is exactly the reason why we shouldn’t try and isolate glute med… in weight bearing, it will work as one part of a complex and brilliant kinetic chain. This was highlighted in a very interesting study recently by Kendall et al (2013) who used a nerve block on the superior gluteal nerve and then performed the Trendelmberg test. Even with a neural block to the gluteal muscles, patients maintained pelvic alignment through the step test, highlighting that in isolation, the glutes alone do not support the pelvis.

One of my preferred, early stage exercises to improve hip control / stability is a single leg isometric movement (figure 2).

Figure 2: Single leg isometric glutes
Figure 2: Single leg isometric flutes (brilliantly demonstrated by @riarottner)

The patient is instructed to rest the contralateral leg against the wall for balance only. All of the body weight should be through the standing leg. Explain to the patient that their foot is superglued to the floor, but you want them to rotate their thigh out (encourage external rotation). There should be no movement from the upper body, bum should be “tucked in” with text book posture and they should hold this contraction for 10s, repeat 10 times. I promise, it will burn your glutes towards the end. Try this yourself and pay particular attention to what else happens further down the chain. You’ll see activation of the VMO and the medial arch will raise as tibialis posterior activates too. A brilliant example of the kinetic chain in action.

“Providing the patient is able to single leg balance, any exercise targeting hip control should be done unilaterally”

Now, there are examples in the patient populations where this is not an appropriate exercise. For example, early stage ACL injuries due to the torsion this creates through the femur and tibia. Instead I would adapt the exercise to something that we were all taught very early on in our physiotherapy degree – a simple small box step, placing one foot from the floor onto a step and back onto the floor – where the standing leg is the working leg. If you are strict enough with posture and lumbo-pelvic control, this is great early stage exercise for the glutes and easily progressed into a full step up, step downs, lateral steps, greater step heights etc. (For exercise progression, please see my shameless plug for my recent Model of Exercise Progression). Kendalls (2013) paper that we mentioned earlier, supports this simple trendelmberg exercise for patients with marked hip abductor weakness. Krause et al (2009) found an increased activation of glute med with single leg exercises compared to double leg stance, so providing the patient is able to single leg balance, any exercise targeting hip control should be done unilaterally.

For the non-weight bearing patients there is reasoning to perform these open chain exercises. While we have said we may not be increasing strength, we know that there is some activation occurring within the glutes so we limit an atrophy and maintain neuromuscular activation while the patient is NWB. Refer back to figure 1- the top exercise for glute med EMG is straight leg hip abduction so even with these NWB patients there are more appropriate alternatives to the clam.


Two of the core elements of physiotherapy is the ability to clinically reason and to provide effective exercise prescription. I would encourage people who regularly use any exercise, not just clams, as part of their mainstay exercise protocol to consider exactly why they are using them. I personally don’t think there are many examples where the clam is an appropriate exercise for sports medicine populations. The exception being NWB patients who are unable to control long lever exercises like single leg hip abduction. Therefore, there is an argument that the clam may quickly become an extinct creature.


Yours in sport