Gluteus Medius Tendinopathy

University of Queensland - Dr Alison Grimaldi, currently doing PhD on lateral hip and muscle function - PhysioEdge podcast #9 January 2012 through ClinicalEdge.com.au

Little known about the deep hip muscles/stabilisers

Lateral hip pain (epidemic)

Trochanteric bursitis still occurs but perhaps not the correct term to be using in the absence of inflammation - ineffective treatment programme led to short term relief with bursectomy and removing compression from the underlying ITB tension

Current research ongoing into the pathophysiology behind the 'trochanteric bursitis' condition

Glut Med tendinopathy is described as lateral hip pain over the greater trochanter region

In the past 10 years, it has been found that the trochanteric bursa is very rarely the primary cause of lateral hip pain.  The glut medius, and in some cases minimus, are more likely primary causes.

Proliferative stage, advanced into degenerative stage by the time the patient presents to physiotherapy - changes within tendon structure, usually related to a compression issue.  ITB places too much compression around lateral hip, causing problems at the insertion point of the glut medius tendon.  Hip adduction is the aggravator.

Protoglycan matrix changes within the tendon, larger protoglycans are produced in response to the compression, which causes the thickening within the tendon and these protoglycans start breaking down causing disorganisation of the collagen fibres which weakens the tendon, predisposing the patient to a tendon tear.

Primary complaint is pain over the greater trochanter - this can often refer along the lateral leg, sometimes into the groin or buttock.  Sleeping on either side can be aggravating.  Night time is often the worst.  At times, walking uphills or standing on one leg, sitting for prolonged periods then standing up are all aggravators.  If quite severe, pain will come on with legs crossed or sitting in a low chair will aggravate.

The more hip flexion, the more compression there is over the lateral hip.  The ITB has insertions into the gluteal fascia and up into the thoraco-dorsal fascia.

The largest groups affected are the post-menopausal women (incidence 4:1 female : male).  This may be related to overweight women who start exercising from sedentary position - tendinopathy will already have been there but asymptomatic until a change in the loading on the tendons, e.g. long walks, charging uphills etc.  This condition also affects younger athletes, especially runners or people doing step aerobics, where excessive hip abduction will flare up condition.  Some males will have the condition if they sit in excessive hip abduction (habitual postures) or if they are just particularly tight along their ITB.  Spending a lot of time in saddle chairs with hip abduction + +, or cycling/running, there is an increase in loading over the lateral hip.

Predisposing factors for glut med tendinopathy include poor movement and postural habits, for example positive Trendelenberg, where hanging on the hip can increase compression over the ITB.  Spending long periods of time in this position with hip abductors lengthened causes a change in length-tension relationships and recruitment patterns.  Hip abductors are less efficient and therefore causes lateral shift and tilt of the pelvis, biasing the superficial muscle system.  The superficial part of the abductor system are over-recruited (TFL and upper glut max) and join into the ITB, causing lots of compressive loading over the lateral hip.  

Other factors like leg length difference, where one leg is in adduction and the other leg in abduction, can cause lateral hip pain.  Also, a scoliosis can cause significant pelvic obliquity and lead to similar issues.

Running around the track in the same direction all the time, age and hormonal factors (oestrogen is important in the health of collagen fibres) and weight increase are all predisposing factors.  

Assessment would begin with a functional assessment - standing posture, single leg function (increases in pelvic tilt, lateral shift (as this increases ADDuction)), walking gait and running gait if appropriate. Challenge them more by dropping their pelvis into Trendelenberg position.

Single leg stance control - 7-10 abduction is normal when measuring with goniometer from ASIS to femur

Single knee bend - significant angle when squatting (IR/add) will increase compression over lateral hip

Pain provocation tests - hip flexion, abduction and external rotation (FABER) is a passive compression test.  Always compare to the other side and check this reproduces their symptoms.  Always use palpation too.

Glut med/min are internal rotators and so a static muscle test where they are pushing the ankle out into your hand may reproduce their symptoms.

Sidelying Ober test, taking into maximum hip adduction (over the bed) then do the static muscle test, pushing up into abduction.

Old literature on trochanteric bursitis - ice, U/S then ITB stretches - will only enhance the problem by increasing the compression of the ITB over the lateral hip!! 

Etiology for the condition (compression issue) - no ITB or flexion/adduction stretches

Massage is beneficial over the long weak abductor system, with trigger point therapy, which is much more appropriate than stretch.  

Strengthening assessment - functional tests of SKB and gait patterns give some initial information, but can also check side lying abduction (hip may drift into hip flexion or pelvis may roll back so they can use their TFL more efficiently)  Make sure you control their pelvis to see what their active range is liked compared to their passive range.  This active-passive discrepancy is normal with 5 degrees but large lag of 20-30 degrees is reflective of what is happening in that deeper system and poor inner range function.

Abduction strength test in neutral may be normal in mid range but does not give a true picture of functional ability in the deep stabilisers.  

Palpation includes TFL and upper glut max  (superficial glut med may be activating well but deep glut med not so much - can look at this with Real Time U/S)  Without U/S, can palpate deep at the lateral hip, halfway between greater trochanter and ASIS, where behind back border of TFL but in front of glut max, before initiating slow abduction in the early recruitment phase, should get swelling in those deeper muscles (concertina effect on U/S) - excessive early activation of TFL can be palpated.

Where does the pain start from or where is the centre of the pain?  Pseudo-radicular pattern appears to come from the lumbar spine (red herring).  If starting in mid/upper buttock, more likely to come from back.  Be sure to check!  Can have coinciding lumbar spine and tendinopathy problems

Treatment


Sleeping - pillow between legs to avoid excessive adduction


Walking - avoid striding out, avoid stairs and hills to reduce tendon loading, as tolerated (does it make your night pain worse? worse the next morning?)


Education


Exercise programme


No Clams or Leg Lifts!! Open chain leg loading over recruits superficial system therefore prefer closed chain.


1. Recruit their abductors in the correct way (easier with real time ultrasound) - can palpate over gluteus med and TFL, static abduction in side lying with knees bent and pillow between legs.  Think about lifting whole shin off bed (not a clam - this can be very provocative as you are flicking the ITB down across the bone and back again)  The static contraction is aimed at recruiting the deeper part of the muscle, low load tendon loading only - this can be useful for pain relief - 10-15 secs x 10, x 2 day as long as TFL not helping out.  


2. Can also do a standing version, leaning with back against a wall first.  Legs just a little abducted, static abduction (bilateral) as if doing the splits or unilateral as if doing a hurdle (3-5 reps).  Gradually increase holding time over a few weeks, particularly in standing as there is generally poor endurance with standing.


3.  Bilateral - weight shift - unilateral.  Start with bridge to bring in glut max as well, and TA/pelvic floor. Often there is poor conditioning of gluteals.  Try not lift too high to avoid back symptoms.  Progress to off set bridge (bring one leg in front of other, loading one side more 70:30) then finally to unilateral bridge, much stronger loading for the abductors, especially anterior abductors as they are also strong internal rotators, trying not to drop the pelvis into relative external rotation (using deep rotators to keep pelvis level)


4. Mini-squat or STS patterning - keep neutral lumbar spine and use glut max, controlling the adduction/internal rotation.  Bilateral in front of the mirror then single leg work with support early on.  Try not to rush to SLS unsupported as this will only exacerbate the add/IR.  Encourage them to put their hand on the wall, focussing on thinking around the g. trochanter, suck in from the side, keeping trunk and lower limb in neutral line.  Then progress to unsupported SLS, SKB then step and land.


By controlling abduction, you can control the compression.


5. Clinical Pilates Reformer (or sliding platform) - push leg into abduction with resistance.  Working into abduction reduces compression and allows you to bias the deep muscle system (superficial muscles have difficulty working in the inner range position)


Success?
If previous failure from previous physiotherapy, usually  involves clams and ITB stretches.  Stop these exercises and educate them about compression.    Short term results with exercise programme but long term, must address the aggravating factors.  Try not to rapidly progress into higher level exercises (single leg work)


Websites
physiotech.com.au
online learning site, access theoretical information on dralisongrimaldi.com
also runs practical seminars