With an intermittent hip case the history has to be thoroughly extracted from the patient with maximum efficiency within the allotted 5 minutes. This really shouldn’t be a major problem with a little practice and it presents an ideal opportunity to aim for a 7 score with some extra practised tit bits thrown in for good measure.With a bit of natural talent at public speaking, some focused tactics and luck a few candidates may even be able to pull off a score 8.

The opposite situation is that  you may be first in with a patient and they can’t stop talking.This is especially dangerous if the info is non-specific and/or not particularly relevant.This can throw a candidate.Having a few less than ideal dry runs in the build up to the clinicals  can work very well in allowing a candidate to work through/out tactics

Candidate: The room was too small and crowded and taking the history was very forced.

In this situation unless a candidate is very practised with their exam technique and quietly confident, they may struggle.

Candidate: “The patient was talking too much It would look very rude interrupting”

The candidate should have anticipated this potential problem and worked out a management strategy for this particular situation    

Pain

This is the most important symptom. Ask about onset, nature, duration, aggravating and relieving factors. True hip pain is usually felt in the groin or anterior hip whilst buttock pain can arise from either the hip or the spine. Radiation to the anterior, medial or lateral thigh is common as is pain referred to the knee.

Ask about numbness and pins and needles to identify any neurological problems or spinal pathology. Pain felt below the knee is suspicious for spinal pathology.

Location

Hip pain often localizes to one of three basic anatomic regions: (1) anterior hip and groin, (2) posterior hip and buttock, (3) lateral hip

Patients often localize pain by cupping the anterolateral hip with the thumb and forefinger in the shape of a “C.” This is known as the C sign

Differential diagnosis of posterior hip and buttock pain includes piriformis syndrome and ischiofemoral impingement and lumbar radiculopathy

Levels of activity

One of the most important questions to ask is about walking distance-how far the patient walk can. What causes the patient to stop? Ideally for THA candidates this should be hip pain with a walking distance of a couple of hundred meters. Be careful considering patients for THA if they have a walking distance greater than 2 miles or if breathlessness from medical co-morbidities prevents a patient from walking any further.

Stiffness

This is usually described in terms of limitation of functional activities.

• Can you put your shoes and socks on?
• Can you cut your toenails?
• Can you get in and out of a bath or do you have to use a shower
• Can you get in and out of a car?
• Can you bend down to pick an object from floor?

Be fast and efficient asking these questions as time is tight for extracting an intermediate case history. Ask leading questions if needed for efficiency of time

Limp

Limping can occur for a number of different reasons including pain, leg length discrepancy, and abductor weakness.

Mechanical symptoms

These include locking, catching, popping, or sharp stabbing pains. Popping and clicking can occur due to many extra-articular causes, most of which are normal.

Past history

Any hip conditions as a child (Perthes, DDH). If Perthes spend some time extracting how the condition was treated as a child. Know the questions to ask for Perthes disease beforehand

Medical conditions and previous operations

Any history of tuberculosis, hypertension, diabetes, asthma, epilepsy, rheumatic fever etc.

Drug History

What medication does the patient takes

If the patient does not take analgesia why not. Is the pain not severe enough, does the patient dislike taking painkillers or is allergic/ suffer from side effects, do the painkillers actually work?

Family History

Any family history of illness

Social history

Smoking, alcohol intake, stairs in the house, home help, carers etc.

It is absolutely essential than a smoking history is asked. Despite its important a number of candidates will forget to ask this in their intermediate case and therefore throw marks away

This is the exam technique that needs to be refined in order to succinctly extract the history part of the intermediate case as applied to the hip. The process can easily be extended to be applied to any joint

So, we ask the patient how far they can walk, do they get pain, can they put shoes and socks on etc

These questions should all be familiar to candidates from their orthopaedic training.

The history will guide candidates as to whether the patient requires a THA or not.

However, candidates only have 5 minutes in the exam to extract this information along also with a social family and drug history and therefore the process needs to be done smoothly and in a well rehearsed polished manner.

You should very comfortably be able to score a 7 for this without any difficulty. This is scoring a 7 to bank for a rainy day when you perhaps don’t do well and score a 5 in another part of the examination.

Most examiners would regard this aspect of the clinical as relatively straightforward and there should not be any room for error. It is perhaps ok to say “no room for error” but more useful to realise it can happen and how to minimise the chance for significant errors actually occurring

In addition, do not allow yourself to feel self conscious or awkward taking the history in front of two examiners. We can all be a bit self-conscious in the exam but blank it out and get on with it.

We realise it is rather simplistic but do not be under rehearsed-keep practicing, practicing and practicing until your history taking is as perfect as it can be.

Preliminaries

Preliminaries are very important in the exam setting even for the short cases where time is tight. At the very least

• Introduce yourself to the patient
• Ask permission to examine the hip
• Ask if their hip is painful
• Explain to the patient that you are going to be moving their hip about and will do your best not to hurt them.
• Make sure that you watch their face throughout the examination and avoid sudden movements.
• Tell the examiner that you would like to start by undressing the patient to his/her underwear including removing socks. They will probably indicate that this is not necessary. At all times be careful to maintain the patient’s modesty.

These preliminaries will use up some of your available 5 minutes worth of time but if it is done efficiently the time spent can be kept to a minimum  

Stay calm and focused and remember

• Think about what you will find
• Listen to what the examiner says    
• Look as though you know what you are doing, and you have examined a hip before              
• Try to appear confident to the examiners     

Exam Etiquette

• Good hand hygiene is important so don’t forget to wash your hands between EVERY case
• At the end don’t forget to thank the patient for their help

This is all exam etiquette and candidates about to sit the FRCS(Tr&Orth) exam should know all these rules but it is easy to forget them in your hurry to come up with the diagnosis

If you do not follow these directives you make it very easy for the examiners to fail, you before you have even begun to examine the hip.

Being rude, rough with patients or impolite are easy objective observations that the examiners will note down and put them in a very strong position to defend their decision to fail you. Other exam failure criteria are more subjective and open to interpretation and variation

Examine in turn

Although examination of the hip should be considered a continuous exercise for ease of purpose it can be broken down artificially in to a number of subsets namely

• · Inspection
• · Gait
• · Limb Length Discrepancy
• · Palpation
• · Thomas test
• · Movements
• · Neurovascular status
• · Specialised tests

We normally test for LLD after ROM as if there is a contracture in a leg the opposite leg needs to be placed in a mirror equivalent position. We will not know if a contracture is present unless we have previously tested for ROM. Some lists have more subsets some less depending on what on what textbook is read and where the emphasis lies.

Inspection of the hip is very much descriptive; it is about what you see.

It is the LOOK part of Appley’s look, feel and move.

Look for general clues

Any walking frame, special shoes or orthosis present?

Does the patient use a stick and is it in the correct hand?

It is perhaps best to mention these things straightway as otherwise they can be easily forgotten about and then the scoring opportunity is lost

General Inspection

If the patient is sitting down in a chair get them to stand up for you.

Look and be seen to be looking.

Observe the patient first in the standing position. Stand with the patient facing you.

Be prepared to support the patient, as they may not be able to stand up unaided.

Start with a general inspection considering the patient as a whole. Consider if the patient looks well, is breathless at rest, is jaundiced or has generalised features of psorasis or rheumatoid arthritis. 

There is always some debate as whether to include general inspection at the beginning of a short case. In everyday clinical practice especially in the clinic it is one of the most important parts of your examination. If a patient is breathless at rest, cyanotic and cannot walk more than 10m because of COPD then perhaps listing them for THA isn’t a good idea.

However, the unofficial exam view is to get straight to the nub of the case and avoid general inspection. If the examiners ask you to perform Thomas test don’t start saying, “the patient looks well for his/her years, is of average height and build” etc as the examiners may get annoyed and think you are wasting potential scoring opportunities. If the examiners have asked you to perform Thomas test, they want you to just get on and perform Thomas test.

The exam is not a real-life clinic; the situation is very artificial and different. Do exactly as what the

examiners direct you to do

Observe the patient from the front, the side and then back.

Is the patient standing upright and straight with the shoulders level?

Is stance comfortable?

Is stance symmetrical?

Look at the attitude of both legs-is there an ER deformity of one leg suggestive of an old SUFE condition

Ask the patient to straighten up their knees and put their feet together

Candidate: “Can you stand up and straight for me please.” (Knees extended and both feet flat on the ground)

Candidate: “Can you straighten you knees for me and bring both feet together

Look and feel for both ASIS and imagine a line between the two. In normal patients this should be level. Pelvic obliquity is present when this imaginary line is not parallel to the floor. The anterior superior iliac spine (ASIS) will be at a higher level in a fixed adduction deformity and lower in a fixed abduction deformity

Look and feel for the level of the ASIS. Is the pelvis symmetrical? If not level…. why not?

What is causing the pelvic obliquity?

• Is there a leg length discrepancy?
• Is there a fixed deformity?

Ask for blocks as a screening test if the pelvis is not level to access for a functional leg length discrepancy. The patient is asked “Do you feel level now” and the blocks are changed as necessary until the patient feels level

Is there any deformity in the coronal plane e.g. Abduction/adduction contracture of the hip?

An adduction contracture of the hip will cause the leg to appear short and results in the ASIS on the affected side to be at a higher level.

Likewise, an abduction contracture of the hip will cause the leg to appear longer and will result in the ASIS on the affected side to be at a lower level

Any thigh or calf wasting?

Inspect the skin for scars, sinus, any evidence of circulatory disturbance etc

Is the patient taking weight equally through both legs?

Look at the feet, is the foot taking weight in a plantigrade fashion or is the ankle or foot inverted, everted or in equinus.

If there a hallux valgus deformity of the big toe or lesser toe deformities it is not unreasonable to comment on this but don’t spend your time going through a whole list of negative findings as this will not score you any additional marks and may end up irritating the examiners.

Look/inspect from the side

Is there an increased lumbar lordosis or is the patient standing with a stoop?

An increased lumbar lordosis suggests a compensatory mechanism to conceal a fixed flexion deformity of the hip

Is there a flexion contracture of the hip or knee? (Deformity in the axial plane)

Lift up the underpants and look at the hip area. Are there any scars from previous surgery or disease? Is there a hip arthroplasty scar? If so, what approach has been used (posterior, Hardinge). Usual description for a scar (surgical/non surgical, early surgical scar, mature surgical scar

The lateral position rather than anterior is the best place to pick up a hip scar and also the least disruptive for a patient’s modesty

Bilateral hip scars-ask the patient if they have any scars on the opposite side

Are the knees fully extended and are both heels touching the ground?

Is there a sinus or dressings present?

A sinus suggests chronic active hip infection which would be very unlikely to pitch up as a clinical case, but this possibility should never ever be fully discounted

At this stage ask the patient “Can you point to where the pain is? If the patient points to the groin it is probably arising from the hip joint, if the patient points to their back or buttock it suggests possible referred pain from the spine to the hip

Sometimes a patient will make a C sign with their hand over the painful hip, fingers anteriorly and thumb posteriorly which is a very specific sign for hip disease usually intra articular pathology (FAI)

Remember to not forget to pull the underwear out of the way (Don’t miss an obvious scar).

Look from behind

Does the patient have a straight or scoliotic lumbar spine, and if so, is it compensated or not? If a scoliosis is present, then sit the patient down on the couch to see if the scoliosis is corrected or partially corrected (this removes the contribution from a LLD)

A degenerative scoliosis may be the reason the patient is complaining of hip pain

Check for any gluteal muscle (buttock) wasting. Gluteal muscle wasting strongly suggests chronic hip disease

Look at the popliteal creases, are they at the same level. Alterations in the level of the popliteal fold suggest a LLD

If there is a flexed attitude of the knee get the patient to straighten the knee as this may reveal of FFD knee or a LLD

Is the heel plantigrade if not this suggests a fixed heel contracture-comment on this to the examiners

Look at the alignment of the lower legs

Is there Hamstring or calf atrophy?

Is there any hindfoot abnormality such as a fixed hindfoot valgus deformity

Screening test of the lumbar spine

Ask the patient to bend forwards-forward flexion.

“Can you bend forwards please sir”

You are assessing forward flexion checking the spine for symmetrical movement, normal rhyme. If the spine is stiff and painful it could suggest referred pain from the spine to the hip

This manoeuvre may appear a bit odd or out of sync if it is not fully explained to the examiners what you are doing and why.

Try not to examine in silence explain your examination routine as you go along

If there are lots of positive finding on inspection it may be reasonable to sum up your provisional finding from inspection at this stage[i].

Candidate: “On general inspection the patient looks well, is standing straight, the shoulders and pelvis are level, both knees extended, and the stance is symmetrical”.

Begin with a last double check for walking aids or else you have missed the opportunity to score your extra points.

Ask the patient to walk away from you and then back towards you. Don’t forget to watch the patient’s shoulders and observe whether they walk in a straight line

Candidate: “Can you walk away from me please and now towards me”

There are a large number of different types of altered gait patterns that candidates could be asked to describe. Correctly identifying an altered gait pattern will give a clue to the possible diagnosis.

Get the patient to walk past you when observing their gait as otherwise you will not appreciate any gait abnormality in the sagittal plane.

The three most important gaits to recognize are the antalgic, Trendelenburg and short leg gaits which are secondary to pain, weakness and shortening

The examiners may ask you what you mean by an antalgic or Trendelenburg gait and you have to be very clear about these definitions and it is worth rehearsing up your answer beforehand

If you are not clear and precise with your definitions the examiners may pounce on you and ask you to clarify your definition/answer which will unnecessarily lose you time and therefore scoring opportunities. Worse still a candidate may become nervous and flustered and the whole case can begin to unravel.

Antalgic gait

Is the gait antalgic?

In painful disorders of the hip a patient will try to avoid weight bearing on the affected side.

Pain in the hip on weight bearing is diminished by reducing the time spent on the affected leg (shortened stance phase).

There is a shortened stance phase of the affected limb with learning of the trunk over to the painful side.

Shifting the centre of gravity of the upper body to a position closer to the femoral head reduces the counterbalancing force required to be generated in the abductor muscles, thus dramatically reducing the compressive across the painful hip joint[i].

Trendelenburg gait

Does the patient walk with a Trendelenburg gait?

With a Trendelenburg gait there is a drop of the pelvis on the opposite side to the affected stance limb. This causes a shift in the body’s centre of gravity to the non-weight bearing side that’s dropped down.

Patients usually compensate and avoid falling over by shifting the upper body towards the weight bearing leg.

This decreases the counter balancing force that needs to be exerted by the weak abductor muscles.

A Trendelenburg lurch is an exaggerated compensatory movement of the trunk over to the weakened side when walking most noticeable if bilateral when it is often described as a waddling gait pattern.

A mild Trendelenburg gait may be difficult to appreciate when examining a patient fully clothed 

Short leg gait

In cases where the limb has become short due to hip disease, the patient tries to bring the foot to the ground by tilting the affected half of the body down.

This involves excessive shift of the centre of gravity towards the short side with a drop of the centre of gravity. It differs from the anatagic gait in that the stance phase is equal (a regular even dip on the shortened side). This gait is only apparent if the limb is shorter than 2cm.Watch the shoulder also dip down on the affected side

Or more simply in the short leg gait the patient will dip down on the short leg during weight bearing on the affected side.

Drop foot gait

Look for a drop foot gait

The leg is lifted more in order to get foot clearance. The forefoot rather than heel touches the ground first.

Gluteus maximus gait

This is seen in weakness or paralysis of the gluteus maximus muscle. Patients will have hip extensor weakness.

The gluteus maximus normally locks the hip in extension as the contra-lateral limb is advanced for the next step. A patient with a weak gluteus maximus necessitates a forward thrust of the pelvis and backward thrust of the trunk. This position places the centre of gravity posterior to the hip and therefore reduces the force that the gluteus maximus needs to generate to lock the hip in extension.

Or more simply the body lurches backwards during the stance phase on the involved side

Candidate: “I’m now going to test how well you stand on one leg. Do you think you can manage this for me? Can you do what I’m going to show you.”

The Trendelenburg test is a very important test and one that candidates must be able to demonstrate well and feel at home with. Candidates get one go only to impress the examiners with this in the real FRCS (Tr&Orth) exam 

Candidate: “Can you kick your foot back for me”

Make sure the patient is well away from the examination couch when performing this test and is not going to hit their foot off the legs of the examination table 

Moreover, be very clear about what you are testing and be able to talk your way through the test as you perform it in front of the examiners.

For most candidates it is not an easy undertaking to perform and interpret a test correctly whilst at the same time explaining what you are doing, why you are doing it and the significance of your clinical findings to the examiners. As well do not forget that candidates will need to explain their instructions in an understandable manner to the patient in front of them.

It is easy to get confused with this happening all together at once but in reality, this is an aspect of what the clinical examination is setting out to assess.

Do not under perform by concentrating too hard eliciting the physical sign whilst at the same time struggling to remember how you are going to explain the test instructions to the patient or what to say to the examiners. Practice this test beforehand to get slick for the real exam

In 1895 Friedrich Trendelenburg described observations on the gait of congenitally dislocated hip patients. Later on, he went on to describe the pelvic inclination on single leg weight bearing, which became known as the Trendelenburg test. This test has been modified repeatedly since the original description.

The Trendelenburg test can be performed either with the examiner in front or behind the patient. The original test was described with the examiner behind the patient so that the dimples overlying the posterior superior iliac spines could be seen to move up and down when the test was performed. Most candidates are more familiar performing Trendelenburg test from the front. Testing from the front is generally more practical and simpler in the examine situation. Furthermore, unless somebody is actually facing the patient, they are often reluctant to stand on one leg particularly if the hip is painful.

There are a small number of surgeons who prefer to perform the test from behind. Reasons include

• This was the original description
• Many patients may have had multiple surgeries with the ASIS being removed in pelvic osteotomies. Therefore, no landmark is present.
• It is a test of visually seeing from the back and feeling the drop of the pelvis with one’s thumbs on the dimples over the PSIS and index finger on the highest point of the pelvis
• Aesthetically it is better to be behind rather than kneeling down in the front of the patient with your face in front of the patient’s pelvis.
• Holding hands in the front has the possibility of false negatives occurring especially in children who use their abdominals muscles to hike up the pelvis.
• You can always ask someone else to hold the hands in front or get the patient to the wall.

By all means perform the test from behind as you prefer especially if it works for you but at least do it properly and be able to explain the rationale behind your choice if challenged[i] [ii] .It is a very different test when performed from behind and candidates should make doubly sure it is done smoothly

The Trendelenburg test is less about semantics and the very fine points of detail and more about your general attitude, confidence and approach to examining a patient provided your basics are correct. The examiners will not fail you if you perform Trendelenburg test from behind, but you must be able to defend this practice with valid reasoning and above all not forgetting to perform it well.

In practice it is much easier if you first demonstrate Trendelenburg test to the patient showing them want you want them to do. It avoids any misunderstanding

There are several methods of performing Trenedelenburg test. Learn one method well, stick to it well and get slick at performing it.

A patient standing on his right leg would be Trendelenburg positive for the right if the left side dipped[iii].

The test is negative (normal) is the pelvis stays level or even rises slightly with the trunk staying over the pelvis and this can be maintained for 30 seconds.

The test is positive (abnormal) if the patient is unable to hold the pelvis level and maintain this for 30 seconds.

Method 1

The examiner stands facing the patient. The patient places their supinated arms onto the examiner’s forearms or shoulders. If the shoulder method is chosen as this will free up the examiners hands to place on the ASIS[iv]. This is a very accurate method of performing the test and our preferred choice but sometimes can be difficult to perform if a patient is very small and/or the examiner is very tall 

Method 2

Sitting in a chair. Great in the outpatient department but not so practical for the exam.Candidates may possibly be able to find a chair in the intermediate cases but much less likely so in the short cases.If  a candidate has only learnt this method then they may become unstuck in the real exam if unable to get hold of a chair.As such probably best to avoid this method for the exam

Method 3

Stand in front of the patient and ask them to hold their hands out in front and place their hands in your hands for balance.

The patient is asked to stand on one leg with the opposite knee bent to 90º without flexing the hip. Ask the patient to stand on their normal leg first and then the affected side.

The examiner can feel how much pressure the patient is using in order to maintain balance.

When the left foot is lifted the right abductor muscles are being tested, when the right foot is lifted the left abductor muscles are being tested[v] .

If all things fail remember the SOUND SIDE SAGS

Critics of this method suggest not enough support and confidence is given to the patient when the examiner holds the patient’s hands.

It has also been suggested that the shoulders or forearms should be used instead for support rather than hands

We believe this method  isn’t a very accurate method of performing the test as the ASIS is not palpated.The test is perhaps more style over substance in that the examiner is not bending down uncomfortably feeling for the ASIS but able to stand up straight.It is also easier to explain what you want the patient to do for the test.

Method 4

The examiner kneels down and asks the patient to place their hands on his/her shoulders

The examiner places his/her hands on the anterior superior iliac spine

The patient is then asked to first stand on the good leg and then the bad leg

The examiner will feel the pelvis dipping down on the affected side and appreciate downward pressure on the shoulder.

This is a very accurate method, but the examiner is kneeling in front of the patient with their face near the patients groin area, which doesn’t professionally look that great.

That said we have seen this method being used very slickly and in practice it didn’t really appear that awkward. This method is more about how natural and confident a candidate performs the test rather than absolutes 

Method 5

Kneeling down with the examiner supporting the patient’s hands with their forearms or elbows. Again, staring straight into the groin without any of the redeeming features of accuracy as you are not palpating the ASIS.Probably best to avoid this method but included for completeness sake

Method 6

Apley’s method. One hand is placed on the shoulder of the test side. The other hand is used to support the hand of the opposite side. This hand is to access downward pressure. The patient is asked to stand on the test side. A positive test is indicated by downward pressure exerted on the supporting hand. This method seems to have fallen out of favour so that despite being well described in the literature we have never come across a candidate actually performing this test method.

That said we have seen this method being used very slickly and in practice it didn’t really appear that awkward. This method is more about how natural and confident a candidate performs the test rather than absolutes

Significance of Trendelenburg’s test

Trendelenburg’s test is done to assess the integrity of the abductor mechanism of the hip, which constitutes of the fulcrum, lever arm and power. With the fulcrum at the hip joint, normal lever arm of the head and neck of the femur intact and power in the controlling group of muscles.

True positive

1.Power failure (weakness of abductors)

• General muscle weakness or paralysis (Poliomyelitis, muscular dystrophies)
• Generalised neurological weakness (Spinal cord lesions (L5 radiculopathy), myelomeningocele)
• Abductor dysfunction (surgery, trochanteric osteotomy, superior gluteal nerve injury)

2.Lever arm failure

• #NOF
• Short neck in coxa vara

3.Fulcrum(pivot) failure (Absence of a stable fulcrum)

• Destruction femoral head (Septic arthritis)
• TB
• DDH
• Osteonecrosis (ON)

Perthes disease is listed as a cause of a positive Trendelenburg’s test for both a lever arm and fulcrum failure

Examiner: How does infection cause a fulcrum failure

Candidate: Chronically dislocated hips secondary to the infection will cause a fulcrum failure

False positives

Gluteal inhibition due to pain secondary to

• Osteoarthritiss
• Osteonecrosis (ON)

If pain is not considered a true positive. Hip pain makes proper assessment of these cases difficult

It has been suggested that a 10% rate of false positives occur

False negative

• Arthrodesed or ankylosed hip

The patient is able to maintain abduction with no abductor function. Sometimes the hip can be so arthritic that it will not move when standing on the affected leg and therefore the pelvis will stay level

False-positive and false-negative responses may occur, but their interpretation can be clarified if the test is properly performed

Invalid if

• Poor balance
• Lack of co-ordination
• Unable to understand instructions

The presence of pain, poor balance and either lack of co-operation or understanding by the patient can lead to false-positive tests, because the test cannot he properly performed. The reason for false-negative tests are that the subject uses muscles above the pelvis to elevate the non-weight-bearing side of the pelvis or shifts the torso well over the weight-bearing side; these can be called “trick movements”.

Be clear why a test is positive. The examiners will want to know why the pelvis dips down and the causes of a positive test!

Normally the pelvis on the non-weight bearing leg rises slightly (Trendelenburg negative) due to contraction of the abductors of the weight-bearing limb.

However, if the pelvis dips on the side of the non-weight bearing leg or cannot be held steady for 30 seconds the test is positive

A delayed positive test occurs if the pelvis eventually dips after continued leg rising for 30 seconds to one minute. This indicates abnormal fatigability of the hip abductors. Some authors have questioned the clinical value of a delayed Trendelenburg test. Any painful hip condition will be positive after the patient has been performing the test for 30 seconds or so

An alternative analysis of the Trendelenburg test is to realise that it is positive for two main reasons either a

• Neuromuscular condition
• or a biomechanical disadvantage 

Neurological causes can be generalised or more specifically localised. Generalised motor weakness is seen in conditions such as spinal cord lesions or myelomeningocele. Specific localised neurological causes could include superior gluteal nerve dysfunction secondary to previous hip surgery.

The biomechanical group includes conditions that affect the abductor muscle lever arm, which place them at a mechanical disadvantage. This includes conditions such as coax vara, hip fractures etc. These conditions shorten the length of the muscles and this significantly weakens their strength.

When standing on one leg the body automatically brings its centre gravity over the weight bearing leg. Because the pelvis dips away from weight bearing leg the upper body may have to swing in an exaggerated manner to achieve a position with the centre of gravity of the body over the weight-bearing limb

If the test is negative it is significant—it means that the subject does not have abnormal hip mechanics

The best place to learn the Trendelenburg test is in the clinic with a patient who has no clue what you want them to do.This will define you as to whether you can give clear instructions to the patient so that you can correctly perform the test.

Candidate: “Could you come and lie down for me, please sir.”

Make sure the couch is completely flat –this more than likely will require adjusting at the beginning of this part of the examination

The couch should ideally have no breaks in it-a flat examination table, but this is not generally provided. You sometimes get what you are given

Multiple breaks in a table is really not great but we live in the real world and sometimes have to make do with what is provided.

The couch should be reasonably firm but not too hard and uncomfortable.

Notice how the patient gets onto the examination couch and whether they appear in pain. Do they clutch the painful leg with both hands and struggle to get on the couch?

More importantly comment on this to the examiners. 

Squaring the pelvis and inspection

Make a particular point of demonstrating that the pelvis is square on the couch (Anterior Superior Iliac Spines are level) even if they are/look straight-it demonstrates that you are checking

Candidate: “The pelvis is level, both ASIS are straight and the legs are square (and straight with the pelvis) and perpendicular to the examination couch.”

Squaring the pelvis is important as all measurements of deformity and leg length discrepancy are based on a squared pelvis.

If the pelvis cannot be squared up, then there is a fixed adduction or abduction deformity at one or both hips. Again, comment on this problem to the examiners  

Re-comment on any significant clinical findings especially if more obvious supine

In particular look for asymmetry, deformity, and rotational alignment of the legs

Any obvious shortening should be commented on

This topic is covered in more detail in a separate section. Sometimes in a short cases you may be specifically asked by the examiners to “just concentrate on examining for leg length inequality only”.

The preferred option is to measure for apparent leg length discrepancy first and then go onto measure for true leg length inequality afterwards.

Apparent leg length discrepancy

With apparent shortening there is no need to square the pelvis

The patient should be lying supine in a straight line with the limbs in a parallel position and deformities not corrected. To achieve a parallel leg, position the unaffected limb is moved to make the limbs parallel.

The measurement is taken from any central fixed point on the trunk (central point of the suprasternal notch, xiphisternum) to the medial malleolus. Textbooks also mention the umbilicus, but some old school examiners may comment that it is not a fixed structure and may not be midline if diseased or had previous umbilical surgery

True leg length discrepancy

Any concealed fixed abduction or adduction deformity must be accurately revealed by squaring up the pelvis. The legs are put into equivalent/identical positions. The affected leg is moved to square up the pelvis (level the pelvis) by exaggerating the noted deformity. The normal limb is then moved to make it in an identical position to the affected leg. 

Check the level of the malleoli

Measure from the ASIS to the medial malleolus. Ideally it would be best to measure from the centre of the femoral head, the normal axis of hip movement

However as there is no surface landmark then the nearest fixed point is chosen this being the ASIS

Make sure the chosen medial malleolus position from measurement is consistent for both sides. Usually the best position is inferior rather than central

Difficulties may be encountered with fixed deformities of either the hips or knees.

If necessary, sequentially measure from ASIS, greater trochanter, medial joint line knee and tip medial malleolus.

Often candidates are directed towards measuring only for a true leg length discrepancy ignoring measurement for apparent leg length discrepancy

It is thought that it is more than enough for a candidate to demonstrate an understanding of how a fixed adduction deformity is taken into account when squaring up the pelvis. Apparent length leg discussion will unnecessarily complicate matters  

If there is shortening in a limb a candidate should quickly go on and perform Galeazzi’s test. Candidates should know this test and be prepared to demonstrate it to the examiners if clinically indicated)[i] 

Candidate: “This test demonstrates whether the shortening is in the femur or tibia”.

Flex the hips to 45º and the knees up to 90º. Place the malleoli together (the test is inaccurate if you are unable to do so)

The candidate assesses the position of both knees from the end and the side of the bed-make a big show of this to the examiners if possible.

Comment on whether the knees are level or at a different level and on the parallelism of the femora and tibia.

Normally both knees are at the same level

When one knee projects farther forwards than the other, either that femur is longer or more usually the contra-lateral femur is shorter

When one knee is higher than the other, either the tibia of that side is longer, or the contra-lateral tibia is shorter

Or more simply:

• Tibial shortening causes the knee to lie at a lower level than the unaffected side
• Femoral shortening causes the knee to adopt a more proximal position

Be careful with more complicated cases of leg length discrepancy where epiphysiodesis has been performed on a normal leg and/or lengthening has been done on a shortened leg.

This test measures supratrochanteric shortening. This test may form part of the limb shortening series of tests that you may need to demonstrate to the examiner 

The patient should lie supine with the pelvis square and limbs in identical positions.

• Identify the ASIS with the thumb and the tip of the greater trochanter with the forefinger (Left hand for right hip and right hand for left hand)
•  Comment on any difference in the distance between ASIS and greater trochanter, which suggests a discrepancy proximal to the greater trochanter.
• Assess the perpendicular distance between points with the fingers of the other hand

This is not strictly Bryants triangle test- it is a test for proximal migration of the greater trochanter[i]  .

Bryants triangle test involves officially drawing out with pen various lines on the pelvis

A perpendicular line is dropped from the anterior superior iliac spine (ASIS) onto the bed.

From the tip of the greater trochanter another perpendicular line is dropped onto the first line (Base of the triangle-point C).

The tip of the greater trochanter is joined to the ASIS’s on the respective sides (Hypotenuse[ii]).

This forms a triangle ABC.Each side of the triangle is compared with its counterpart on the opposite side

The length of BC line is compared between the two sides.

Relative shortening on one side indicates that the femur is displaced upwards as a result of a problem in or near the hip joint.

If the problem is bilateral, Bryant’s triangle is less helpful.

Shortening above the trochanter may be caused by destruction of the femoral head, acetabulum or both, a dislocated hip, coxa-vara deformity of a mal-united inter-trochanteric fracture.

“I would like now to perform Bryants triangle test to see whether there is any shortening above the trochanter (supra-trochanteric).

When Bryants triangle is constructed the perpendicular distance is shorter by 2 finger widths between the ASIS and greater trochanter on the right side

Other tests are described that are used to roughly access the position of the greater trochanter. In clinical practice these are usually omitted as they are difficult to perform and not particularly accurate. For the exam they are probably worth knowing about so that the examiners do not catch you out[iii].

These tests include Nelatons line, Schoemakers line and Chienes line.

If the case is intermediate and primary focused on leg length discrepancy and a candidate is doing extremely well these tests could potentially be asked about at the end of either the clinicals or discussion. If a candidate is average it is unlikely, they will get through the case material fast enough to talk about. If it’s a short case of leg length discrepancy it is highly unlikely even an exceptionally well performing candidate will cover enough ground to get to discussing these tests[iv].

The examiners may be able to progress on and discuss these tests usually at the end. If it’s a short case leg length discrepancy even with a very good candidate, it is pushing things to think they will find enough time to get through the

The patient lies with the affected side uppermost. With the hip flexed up 90⁰ the tip of the greater trochanter should lie on or below a line connecting the anterior superior iliac spine and ischial tuberosity. In cases of supra-trochanteric shortening the trochanter will be proximal to this line

With the patient lying supine a line joining the ASIS and tip of the greater trochanter is extended on the side of the abdomen on both sides. Normally, these lines meet in the midline above the umbilicus.

In the case of one of the greater trochanters migrating proximally, the lines will meet on the opposite side of the abdomen and below the umbilicus. If the problem is bilateral the lines will meet at or near the midline but below the umbilicus.

With the patient lying supine lines are drawn joining the two ASIS and the two greater trochanters.

Normally, these make two parallel lines. In the case of one trochanter moving proximally, the lines will converge on that side

It is very easy to forget to palpate the hip during your examination. In fact, examiners still like to see this performed. The difficulty is that hip joint is too deep to access for the presence of an effusion or synovial thickening. It is important to be systematic with palpation

Access skin temperature

Tenderness may be elicited in and around the joint

Feel for any abnormal swelling or masses such dislocated anterior femoral head (Lump sign), lymph nodes, hernias, aneurysms.

Palpate the ASIS, along the inguinal ligament, femoral head, adduction longus insertion, lesser trochanter, greater trochanter (trochantric bursitis) and ischial tuberosity

Halfway along the inguinal ligament one can feel the femoral pulse, deep to this point is the femoral head

Is there a general surgical problem? If there is a swelling you should be able to examine for a hernia[i].

If the presentation of hip pathology is vague percussion on the heel pad in the extended position of the leg and over the trochanter usually induces discomfort and/or pain in the groin region if there is any disease or injury of the hip.

This is classic test material. The examiners will almost certainly ask you to demonstrate Thomas test as part of an intermediate case examination of a hip condition. The test is also well known to crop up in a hip short case. The test is usually well described by most candidates but often poorly performed in the pressure/stress of the real exam. Candidates should repeatedly practice this test and be prepared to demonstrate it well. Again, like the Trendelenburg test you get one chance to shine with this in the real exam.

The aim is to remove the compensatory lumbar lordosis so that the flexion deformity of the hip becomes obvious. Hugh Owen Thomas described this test in 1876.He described his test on a naked patient laid on a hard table or other hard surface. A patient with a fixed flexion deformity at the hip will compensate when lying on his or her back, by arching the spine and pelvis into an exaggerated lordosis. A hand is placed under the back to assess the lumbar lordosis. Some examiners prefer the arm being prone (in preference to supine), as they believe this is a more sensitive method of detecting obliteration of the lumbar lordosis. This could be interpreted as splitting hairs but is mentioned for completeness sake

• A common mistake in the stress of the examination is to forget to put a hand under the lumbar spine to demonstrate that the lumbar lordosis has been flattened. This is a major omission and a difficult situation to recover from
• Another significant error is to be too gentle and not completely remove the lumbar lordosis. You must however be sensible and do not hurt the patient flexing up the opposite hip as it may also have pathology such as a painful arthrosis.
• At the same time do not maximally flex the hip as this will cause the pelvis to flex and may lead to a false impression of a FFD
• If the patient has a total hip replacement on the opposite side do not dislocate it by flexing the hip up too vigorously. Most surgeons would not perform this test for fear of dislocation. A small number of surgeons may suggest that you can perform the test in a controlled manner by gently flexing the contralateral leg while asking the examiner to put their hands underneath the lumbar spine to obliterate the lumbar lordosis. 

The angle subtended between the back of the thigh and the bed will be the angle of fixed flexion deformity. Severity of the flexion contraction at the hip will not be appreciated if the hip is allowed to abduct whilst the Thomas test is performed.

Controversies

At the start whether to get the patient to bend both knees to up 45°or start by flexing up only the sound hip. Flexing the sound hip only is slicker and easier to perform but deviates from the classic Thomas test and may not go down well with an old school examiner.Having the patient hold both knees up to their chest together can be uncomfortable for an elderly arthritic patient.Our suggestion is if the patient is struggling with being examined flex up only the sound hip.However if they are younger and fitter then  bending both knees up to 45°is probably ok and more accurate

Whether to stick to testing one hip at once or try to combine the examination to include measuring flexion in the opposite hip. Our advice would be to keep things simple, one hip at a time, less confusing for yourself unless you are supremely confident you can do this slickly.

Thomas test is difficult to perform:

• In the presence of an ipsilateral ankylosed knee (in extension). Flex the contra lateral hip as normal but you may need to help support lifting the affected side to truly measure the fixed flexion deformity of the hip
• In heavily built or obese patients, it is not easy to perform because of incorrect appreciation of obliteration of the lumbar spine
• In bilateral fixed flexion deformity of the hips. In this situation put the patient prone on the couch so that the trunk lies fully supported on the couch and hip region is at the edge of the couch. Support both knees with your hands. The hips are then extended until passive resistance is felt.

Decide how you are going to do it and stick with your own method. Similar to the Trendelenburg test many examiners would suggest it is not about sticking to absolutes with this test but about attitude and appearing confident with what you are doing. If you appear hesitant and are also deviating too much from classic teaching, you may get challenged by the examiners as to what exactly are you doing to the patient. Be prepared to defend your practice

Unusual situations

1. How do you perform Thomas’s test with a fixed spine such as ankylosing spondylitis?

Proceed as normal flexing the opposite side to its fullest and by flexing the opposite side this decreases whatever compensation there is in the lumbar spine. The lumbar spine does not need to be flat on the bed but all you need to be doing is obliterating their compensation

1. How to perform Thomas’s test in a patient with an arthrodesed contralateral hip

Still lift the contralateral hip until the lumbar curve flattens. At this point this measures the fixed deformity of the hip

1. How to do a Thomas test in a patient with an FFD at the knee

Place the patient so that the knee is at the side of the couch to eliminate the effect of a FFD at the knee. The end of the couch can also be used but side is much easier to do and gives you less opportunity to slip up

Hip movements are probably the most important clinical sign and the key to the diagnosis of hip disease.

Most classic textbooks mention measuring active movements first and then measuring passive movements afterwards. This allows a comfortable range of movement of the hip to be detected first. Passive movement beyond this range can then be sought with caution, keeping the patients face under observation so as to avoid distressing the patient (and the examiner).

This is fine for the clinic but in the exam setting candidates should measure active movements first and then quickly continue on with passive movements afterwards to save time

Don’t forget to stabilise the pelvis as you move the hip through a range of motion otherwise you will get a false impression of movement. When the pelvis starts moving then there may or may not be co-existing hip movement probably just the pelvis, but you cannot tell for sure. If movements are severely restricted in all directions think of rheumatoid arthritis, tuberculosis, septic arthritis.

If hip movements are reasonably well preserved but there is pain and terminal limitation of movement think of osteoarthritis of the hip

One or more movements may be more limited than others if the head is deformed in such cases as Perthes or AVN.

Log rolling test[i]

A very quick and simple test to judge the irritability and freedom of movements in the hip before a more formal range of movement testing.

Feel for resistance on rolling the leg. This is a very accurate test for hip pain as it moves only the femoral head in relation to the acetabulum and the surrounding capsule. Remember to move the patella and not the foot.

The log roll test can also be included as part of the soft tissue evaluation of the hip. Capsular laxity can also be assessed with this test. The examiner rolls the leg from maximal internal to external rotation and then lets the leg rest in whatever position it falls into. The test is positive for capsular or ligament laxity when there is no obvious end point and the affected leg lies in more external rotation than the unaffected side. Eliciting a clicking or popping sensation may indicate an acetabular labral tear

This test is not absolutely essential and is often omitted by most candidates.There is not a general expectation from the examiners that it needs to be performed.As such if a candidate decides to perform the test in the exam it is important to remember to tell the examiners what test they are performing and why. 

Flexion[ii]

Hip flexion is tested in the supine position with the knee flexed to prevent hamstring tightness.

Do not allow the hip to go into external rotation with flexion[iii], keep the hip neutral as allowing the hip to fall into external rotation essentially this is measuring a different range of hip movement

The primary flexors are iliacus and psoas muscle. Secondary muscle flexors are rectus femoris, sartorius, tensor fascia lata, pectineus and the adductors.

Do not forget to stabilise the pelvis when testing for hip flexion,this is a serious omission resulting in candidates being marked down in their final score.Likewise with a fused hip failure to appreciate no  hip movement is occurring is another serious mistake that may result in a short case of hip fusion being failed.   

Extension

Be careful if the patient is elderly and this movement is perhaps better avoided in this situation. Best measured in the prone position with the knee straight.

The main hip extensor muscle is gluteus maximus with some minor contributions from the hamstrings.

Rotation in flexion

Flex the affected hip to 90º, knee flexed to 90º and use the leg as a lever arm to do the rotation. This movement is referred to as the GP test for hip pathology as it is fairly straightforward and very accurate for hip pathology

Internal rotation occurs when the foot turns out and external rotation occurs when the foot turns in. Do not get confused because although the foot moves laterally (externally) the hip rotates internally (medially). Do not mix up internal and external rotation of the hip which is surprisingly easy to do during the stress of the clinicals

Hold the leg with one hand and stabilise the pelvis with the other hand

External rotation in flexion is usually slightly greater (50º) than internal rotation (40º) except in cases of excessive femoral anteversion.

Early signs of hip pathology can be picked up by evaluating rotation in flexion.

Rotation in extension

Rotation in extension allows a clear and convenient demonstration of restricted movement

The patient needs to be placed prone on the couch with the hip extended and the knee flexed at 90⁰

Be careful if there is a fixed flexion deformity of the hip or the patient is in pain

This test is easiest to do in children and is probably not that particularly appropriate if a patient is frail and elderly.

The knee is flexed up to 90⁰ and feet held apart to demonstrate a normal range of internal rotation of 35⁰ and crossed over to demonstrate external rotation of 45⁰

This movement can also be measured supine using the patella rather than the foot as a guide

Abduction

Hip abduction is measured with the patient lying supine

Abduction can sometimes be difficult to quantify due to lumbar and spinal movement. The are two ways this problem can be avoided.

1. Keeping one hand over the opposite ASIS whilst moving the hip will detect any movement of the ASIS and hence pelvis. False abduction is detected when the contra-lateral ASIS moves.

Make a show of feeling where the ASIS are and fixing them with your forearm and then accessing the arc of movement up to the point where the pelvis begins to move to ensure that any movement detected is not due to pelvic rock.

1. Abduct the normal hip first and leave the leg over the edge of the couch. Now abduct the abnormal leg, the normal leg will steady the pelvis. Be careful not to hurt the patient if there is co-existing hip disease in the normal hip.

The normal range of movement is 40º

Active abduction is performed primarily performed by gluteus medius with secondary help from gluteus minimus, tensor fascia lata and the upper fibers of gluteus maximus. 

Adduction

True adduction can only be measured if the contra-lateral leg is in a position of abduction. If it is in a neutral position, then a degree of pelvic tilt comes into play as the examined leg crosses over the contra-lateral static leg

In practice most candidates move the examining leg over the good side by flexing the hip slightly to measure adduction.

As such this movement is best assessed with the normal hip in abduction as this avoids pelvic tilt and allows a more accurate measurement of hip abduction as the point at which the pelvis starts to move is better appreciated.

As with abduction, the pelvis must be stabilised when measuring the range of movement.

The normal range is 25º

Active adduction is performed by adductor magnus, brevis, longus, pectineus and gracilis

Always examine the lumbar spine in your intermediate case.

In the short cases ask to examine the lumbar spine, but expect to be told to leave it

Always examine the knees in the intermediate case or go through the motions of beginning to examine the knees waiting for the examiners to perhaps move you on.

Distal neurovascular status

Examination for pulses and neurological deficit of the limb must always be done in a case with hip disease

Ask the patient to abduct the leg against gravity whilst palpating the gluteal muscles

Push down for resistance

Use the MRC grading of power

This is an important test in patients who have had previous hip surgery to check for abductor power.

The patient lies prone with the knees flexed to 90^°. The examiner palpates the posterior aspect of the greater trochanter.

The hip is then passively rotated medially and laterally until the greater trochanter is parallel with the examination couch or reaches its most lateral position.

The degree of anteversion can then be estimated based on the angle of the lower leg with the vertical

This tests for tightness of the iliotibial tract.

Abduct the hip with the knee flexed and slowly extend the knee

The test is positive if the leg stays elevated (due to IT band tightness)

Flex the knee (relaxing the IT band) and the leg should drop back to the couch

A negative result is when the thigh falls to neutral or adduction

around the hip and may now ask you to demonstrate apprehension type tests if appropriate

These are useful when examining a young patient with hip pain in which the diagnosis is not entirely clear.

Anterior Impingement Test

With the patient supine, the hip is flexed gently to 90°, adducted and internally rotated. If this reproduces the patient’s pain in the groin it suggests an anterior labral tear. A positive test may sometimes be accompanied by a clicking or popping feeling.

MRI of the hip or hip arthroscopy may be indicated.

Posterior Impingement test

The patient lies supine at the edge of the examination couch with the affected leg dangling. The contralateral leg is held in flexion while the examiner fully extends the affected hip while abducting and externally rotating the leg.

This is also known as the Fabere sign (Flexion, Abduction.External Rotation and Extension)

The patient is asked to place the lateral malleolus of the test leg above the knee of the extended unaffected leg. This is the so called “figure 4” position. This test can be used to differentiate pathology arising from the posterior aspect of the hip and the sacroiliac joint.

Pain during this manoeuvre is one of the very first signs of osteoarthritis of the hip. It is also a valuable test for posterior impingement.

The test may be amplified by pressing downwards on the test knee. Pain with downward compression indicates a sacroiliac joint condition as this joint is compressed in this position

The piriformis test assesses pathology within the piriformis muscle itself or irritation of the sciatic nerve by the muscle’s margin. The examiners can definitely ask about this test as part of the differential diagnosis of external causes of hip pain. The patient lies on her side with the affected leg uppermost. The hip is then flexed to 45° and the knee to 90°.With one hand the examiner stabilizes the pelvis and the other adducts the flexed hip. This stretches the piriformis muscle. Localised pain over the piriformis muscle suggests a tendinitis but if pain or irritation occurs along the distribution of the sciatic nerve this suggests compression of the nerve in the muscle

Causes of piriformis syndrome include hypertrophy of the muscle, trauma, excessive gym exercises, aneurysm of the inferior gluteal artery, spasm or inflammation of the muscle, myositis ossificans