chapter 5 – management of the hypermobile adolescent
DESCRIPTION
movimientoTRANSCRIPT
CHAPTER CONTENTS
Introduction 51
Onset of symptoms 52
Growth 53
Common problems In the hypermoblleadolescent 54
Spinal problems 54Pars interarticularis defects 54Spondylolisthesis 55Lumbar disc lesions 55Non-specific low back pain 55
Training lumbar control in the adolescenthypermoblle 56
Primary training 56Secondary training 56
Cervical spine - acute wry neck 57
Hip 58
Shoulder 58
Knee 59Anterior knee pain 59Patellofemoral instability 60Genu recurvatum 60
Foot 61
Psychosocial factors 62Compliance 62
Sport 63
Lifestyle adaptations 64
Conclusion 65
5
Management of thehypermobile adolescent
Alison Middleditch
Aims1. To review the normal developmental changes
that occur during adolescence and considertheir impact on adolescents withhypermobility
2. To discuss the musculoskeletal problems thatoften affect hypermobile adolescents
3. To discuss psychosocial issues, the role ofexercise and sport, and management of thehypermobile adolescent
INTRODUCTION
Hypermobility in adolescence is complicated byadditional problems related to the individual'sphysical maturity and sociological development.The physical, physiological and psychologicalchanges that occur during adolescence have abearing on the diagnosis and management ofjoint hypermobility.
Joint laxity is usually greatest at birth,decreases during childhood, and continues toreduce during adolescence and adult life. Thetightness or relative laxity of a ligament is animportant element in governing the availablejoint range of an individual. Laxity of ligaments isdetermined by an individual's genetic make-up,and the genes that encode collagen, elastin andfibrillin are important in influencing joint flexibility. A number of other factors have an impacton range of joint movement, such as the shape ofthe joint surfaces, muscle length, and the mobilityof the neural structures. These factors continue tochange throughout the adolescent growth period,
51
52 HYPERMOBILITY SYNDROME
thereby affecting the extent of range of movementin both those who have hypermobility and thosewith 'normal tissues'. Although an adolescentmay be unaware that they are hypermobile, theymay believe themselves to be 'double-jointed'and use their excessive range of movement toperform 'tricks'. The hypermobile condition mayonly become apparent if an injury occurs or theindividual develops pain or other problems.
Hypermobility may be inherited or acquired,and joint mobility can be increased with training.Those with 'normal tissues' can increase range ofmovement by stretching, and this is typically seenin ballet dancers and gymnasts. It is probable thatindividuals who have joints of average flexibility have better protection from injury by their'normal tissues', and those who have developed ahypermobile range from specific training enhancethe stability of their joints through good musclestrength and control. Although an increase injoint laxity is considered an advantage for somesports and activities, the generally weaker tissueof a hypermobile individual means that they aremore susceptible to injury (Grahame and Jenkins1972). The joints are frequently less stable andvulnerable to subluxation or dislocation. A feature of hypermobile tissues is that they are lessresilient, so that muscle tears and tendon-osseousattachment lesions (e.g. epicondylitis and plantarfasciitis) occur with greater ease (Grahame 1999).
Children with hypermobility are often attractedto physical activities such as gymnastics and ballet. Good muscle tone, particularly of the deeppostural muscles, helps to protect against injuryand improves joint stability. Hypermobile balletdancers have a higher incidence of injuries thannon-hypermobile dancers (Klemp et al. 1984)andthese injuries commonly affect the feet, knees andlower back. Flexible joints can have a tendency toinstability, and without adequate muscular support movements such as handstands and balancing on one leg can be more difficult. Hyperlaxityof the tarsal and first tarsometatarsal joints canprevent a ballet dancer from dancing en pointe(Beighton et al. 1989a).
Children and adolescents are susceptible tothe same acute and overuse sporting injuries asadults (Thein 1996), and the incidence of injury isgreater in adolescents than in children (Zaricznyjet al. 1980,Apple 1985).An understanding of normal development and the physical, physiologicaland psychological changes that occur duringadolescence is particularly important whendealing with a hypermobile teenager who has asporting injury.
Hypermobility is also considered to be anadvantage for musicians. The increased flexibilityimproves dexterity and allows a greater span ofthe fingers. Larsson et al. (1993) found that violinists, flautists and pianists who have lax fingerjoints suffer less pain than those who have relatively stiffer joints. Musicians require many ofthe same characteristics as athletes: they needexcellent coordination, good muscle strength andendurance. Musicians are susceptible to the sameacute and overuse injuries as athletes, and a youngmusician who has hypermobility will benefit fromincorporating warm-up, cool-down and strengthening exercises into their practise sessions. Areview of the adolescent hypermobiles whoattended our clinic over a 2-year period showedthat about 20%presented with problems related toplaying an instrument (unpublished data).
ONSET OF SYMPTOMS
Approximately 7-10% of the school-aged population has loose joints and occasional pain in jointsand muscles, particularly at night. Symptoms arising from hypermobility may commence at any age(Beighton et al. 1989b); however, Kirk et al. (1967)described a study in which three-quarters ofhypermobile subjects had developed symptomsbefore the age of 15. A feature of normal growthand development is increasing muscle strength(Malina 1985), and in general joint laxity declineswith age (Grahame 1999). These normal developmental changes in the soft tissues may be oneof the reasons that some hypermobile teenagers
MANAGEMENT OF THE HYPERMOBILE ADOLESCENT 53
experience an improvement in their symptoms asthey get older.
Common symptoms among hypermobile adolescents include joint and muscle aches which areoften worse at night, excessive clicking of joints, ahistory of subluxation or dislocation (particularly of the patella or shoulder), non-specific lowback pain, joint effusions, repetitive strain injury(RSI), and a feeling of vulnerability as if the jointmay lock or 'go out of place'. Symptoms are oftenworse the day following vigorous or unusualexercise, or after periods of prolonged inactivitysuch as a long car journey.
Hypermobility syndrome may mimic juvenilechronic arthritis (Bird and Wright 1978), and ithas been reported (Gedalia et al. 1985) that 66%(21) of 32 children with episodic arthritis hadgeneralized joint laxity. A diagnosis of hypermobility syndrome may be appropriate in adolescents who have musculoskeletal complaints andjoint laxity but no demonstrable evidence ofsystemic rheumatological disease, providing theyfulfil the Brighton Criteria. Hypermobility syndrome is underdiagnosed (Beighton et al. 1989b)and these children are often dismissed as havingteenage growing pains or emotional problems.
A review of hypermobile adolescents whoattended our clinic over a 2-year period identifiedsome common traits. As small children, those withhypermobility may have a history of walking orcrawling late. Indeed, some never crawl- possiblybecause of poor stability in the elbow and shoulder, and move around by bottom shuffling. Hypermobile children have difficulty in sitting still forany length of time, probably owing to their inability to find a comfortable, stable position, and theyhave a tendency to fidget. In the classroom thismay result in the child being labelled as inattentiveor hyperactive. Adolescents have particular difficulty sitting on high stools in science laboratories,as they offer no back support. The problem canbe compounded further if the stools do not havea footrest, so that there can be no weight transference of the body through the legs. The inabilityto place the feet on a footrest or the ground also
compromises the stability of the trunk. Hypermobile children may bruise easily, are oftenclumsy, have poor coordination, and may fallover more frequently than children with 'normaltissues'.
GROWTH
In adolescence the rapid rate of growth can be thetrigger for the onset of problems. When treatingthe adolescent with hypermobility it is essentialto have a thorough understanding of normaldevelopmental characteristics to provide a basisfor realistic expectations during management.
During early childhood both boys and girlsgrow at a similar rate in height and weight. Themost rapid rate of growth occurs just before birthand it then remains relatively steady until adolescence. Before adolescence the rate of growthis disproportionate throughout the body: thelength of the limbs increases more relative to thetrunk, and the centre of gravity moves caudally.The peak growth rate (adolescent growth spurt)occurs approximately 2 years after the onset ofpuberty (Porter 1989). The onset of puberty isapproximately 10.5 years in girls and 12.5 yearsin boys. During this period of rapid growth thereis a disproportionate rate of growth of variousbody parts, resulting in a change of body shapeand proportion. The average girl adds between 6and 11cm and boys 7-12cm to their height during this period. Most girls have reached 99'}{) oftheir adult height by the age of 15, whereas boysreach adult stature between 18 and 21 years.
During the growth spurt, the growth of thebony elements often outstrips that of the softtissue elements (Thein 1996). It is this stage indevelopment that tissues become overstressedin a cumulative overload, and many adolescentsfind that their joints are less lax and movementsare stiffer. Many experience muscle tightness,and this may be one of the causes of growingpains in children. Typical postural changes at thistime include tight thoracolumbar fascia, tight
54 HYPERMOBILITY SYNDROME
hamstrings, increased lordosis, decreased abdominal strength and a compensatory thoracic kyphosis. Some hypermobile adolescents will not noticeany increase in stiffness, but others will noticea reduction in joint laxity in a range that nevertheless remains hypermobile. As changes occur inthe muscles and more sarcomeres (the contractileunit of muscle) are laid down, flexibility mayimprove again.
Weight increases steadily throughout childhood and adolescence. Peak weight velocity follows peak height velocity by 0.25 years in boysand 0.63 years in girls (Tanner 1966). A studyof children throughout puberty noted that boysincrease in weight by an average of 113%, andgirls by an average of 67% (Buckler 1990). Thisincrease in mass (body weight) substantiallyincreases the ground reaction forces to which thejoints are subjected, and the more fragile tissuesof the hypermobile child become vulnerable ifjoint stability is further compromised by poormuscle control.
Increases in muscle mass and strength areproportional to weight gain during adolescence(Thein 1996). A boy's muscle mass will doublebetween the ages of 11 and 17 years, and peakheight and muscle growth occur simultaneously.A girl's muscle mass doubles between 9 and 15,and the fastest growth is approximately 6 monthsafter peak height velocity.In both sexes increases inmuscle strength closely follow increases in musclemass, which occur approximately 9-12 monthsafter peak height and weight gain (Porter 1989).
Bone maturation is the process whereby thetissue undergoes changes from the embryonicrudiment of bone to the adult form (Roche 1985).Before puberty chronological age correlates wellwith bone age. However, during adolescencebone age is closely related to adult maturitylevels, so that bone age is related to the timing ofpuberty and growth in height in an individual(Roche 1985). Hence, two adolescents of the samechronological age can have different levels ofbone maturation owing to differences in timingof the onset of puberty.
COMMON PROBLEMS IN THEHYPERMOBILE ADOLESCENT
Adolescents may develop symptoms in anyjoints, but those frequently cited as a problemarea are the back, knees, shoulders and elbows.Hypermobile subjects are particularly susceptible to back pain, and the incidence of lumbar discprolapse, pars interarticularis defects and evenspondylolisthesis occurs with increased frequency in hypermobile individuals (Beightonet al. 1989b).
SPINAL PROBLEMS
Pars interarticularis defects
Spondylolysis is a break or discontinuity in theneural arch. Although it is not a congenitaldefect, there is a strong familial incidence (Turnerand Bianco 1971). The incidence of the appearance of this lesion is greatest between 5X and 6~
years (Wiltse et al. 1976) but symptoms oftenappear in adolescence, particularly at the time ofthe growth spurt (Dyrek et al. 1996). The parsdefect is considered to be a stress or fatigue fracture caused by repeated hyperflexion, hyperextension and twisting, and consequently it ismore prevalent in the adolescent who plays sport.Spondylolysis has been reported with greater frequency in gymnasts, and Jackson et al. (1976)observed that gymnasts with low back pain initially had negative X-rays that then progressedto evident defects in the pars interarticularis.Diagnosis is made from an oblique radiograph. Ifa stress fracture is suspected and the standardview X-rays appear normal, a bone scan maybe required to discount the possibility of a spondylolysis. Spondylolysis has also been reportedwith greater frequency in a variety of sports,including dancing, tennis, cricket (particularlybowlers), swimming, hurdling and diving.
The stress fracture creates a potential area ofinstability and symptoms are initially exacerbated
MANAGEMENT OF THE HYPERMOBILE ADOLESCENT 55
by sporting activities, but may become more constant if the defect is not identified. Commonly theteenager will experience pain on flexion or extension that may be reduced if they contract theirtransversus abdominis muscle before doing activemovements. If it is identified in the early stages,conservative treatment of rest followed by controlled activity is successful in the majority ofcases. Improving the strength and control ofthe local muscles that stabilize the lumbar spineand pelvis is an essential part of the management. These lesions can take up to 16 months toheal (Dyrek et al. 1996), but some adolescents mayhave symptoms severe enough to need surgery.
Spondylolisthesis
A spondylolisthesis occurs when there is a separation of the pars interarticularis defect and aforward slip of one vertebra on another. Thiscondition is more likely to occur in the adolescentgrowth spurt. The adolescent presents with backpain that may be referred to the legs, loss of lumbar lordosis and hamstring spasm. Diagnosis ismade from a lateral radiograph. A slip of 25% orless (grade 1) and even a slip of 50% (grade 2) canoften be treated successfully with exercises toimprove the muscles that control and stabilizethe lumbar spine and pelvis. Larger slips (grades3 and 4) may require surgery.
Lumbar disc lesions
The increased ligamentous laxity in hypermobility can create greater stresses on the lumbarintervertebral discs, particularly at the end ofrange of physiological movements. Structuresthat help to restrain lumbar spine movementinclude the facet joints, the interspinous ligaments and the discs themselves. The spine doesnot have the protection from 'normal tight' tissues and the discs are vulnerable to the strains ofdaily life. Disc damage may be due to a singletraumatic incident or result from the repetitivemicrotrauma and strains to which it is subjected
during everyday activities. Between 30 and 60%of adolescents with disc problems report an association with significant trauma (Grieve 1988a).
A feature of adolescent disc problems is theseverity of their objective signs in comparisonwith adults. They often present with back painand unilateral leg pain (although it may be bilateral). Movements and activities that increaseintradiscal pressure, such as coughing, sneezing,sitting and lifting weights, aggravate the pain.The pain is often reduced in the lying positionbecause the intradiscal pressure is less whenaxial loading on the spine is reduced. These individuals often have a loss of lumbar lordosis, a lateral shift, and straight-leg raising can be limitedto below 30° on the affected side and 45-65° onthe unaffected side. In severe cases neurologicaldeficit may develop.
Management of an adolescent disc problem isnormally conservative, and surgical interventionshould only be considered if there are significantneurological changes. There is tremendous potential for healing and shrinkage of herniated discmaterial in the adolescent, although healing timescan be slow, particularly in the hypermobile.Treatment programmes may include manualmobilization techniques as well as exercises tobrace the spine.
Vigorous manipulation of a hypermobile spinethat lacks normal tight ligamentous control mayput excessive strain on the disc and create further damage, potentially turning a bulging discinto a herniation. Excessive rotational forces arelikely to be the most damaging and should beavoided in the hypermobile adolescent.
Non-specific low back pain
Non-specific low back pain is a common problemin hypermobile adolescents and occurs in theabsence of demonstrable radiological change oridentifiable back pathology. A prospective studyof 102 cases of backache (age range 16-70 years)and their relationship to ligamentous laxity wasreported by Howes and Isdale (1971). The majority
56 HYPERMOBILITY SYNDROME
of patients with no definite diagnosis had jointlaxity, and Howes and Isdale used the term the'loose back syndrome'. Other authors have identified similar syndromes (Chabot 1962, Hirsch et al.1969). Non-specific low back pain often starts inadolescence, when the teenager complains ofrecurrent low back pain. Neurological signs areabsent and examination of the individual revealsthey have an increased lumbar lordosis or a swayback type posture. Relief of symptoms with manipulative treatment is usually only temporary, withlonger-lasting improvement gained from isometricback exercises (Howes and Isdale 1971).
Adolescents with hypermobility who sufferwith non-specific low back pain often have poorfunction of the deep trunk and back muscles thathelp to stabilize the spine, control intersegmentalmovement and maintain a balanced spine andpelvis. This control is frequently inadequate instatic postures and is compromised further during daily functional activities, particularly thosethat are performed at speed or include a changein the direction of motion. These teenagers needa specific programme aimed at training themuscles of the spine and pelvis to assist in bracingthe spine and controlling the forces that affect it.
TRAINING LUMBAR CONTROL INTHE ADOLESCENT HYPERMOBILE
Primary training
The first is a cognitive stage where the individualneeds to gain a high level of awareness of findinga lumbar spine neutral position and training thedeep muscles. A feature of hypermobility is poorkinaesthesia and reduced proprioception (Hallet al. 1995), so that even finding lumbar spine neutral can be challenging. Hypermobile teenagersoften find it particularly difficult to find lumbarspine neutral in four-point kneeling, and mayneed to start in a supine position to train independence of the pelvis and lower lumbar spinefrom the thoracic spine and hips without global
muscle substitution. As soon as possible trainingshould be done in sitting or standing, whereincreased proprioception will be helpful.
Once lumbar spine neutral can be achieved theindividual progresses to train lateral costal anddiaphragmatic breathing, maintaining lumbarspine neutral.
The next stage is training the middle and lowerfibres of transversus abdominis and the pelvicfloor. The patient is instructed to draw the lowerabdomen 'up and in' without any global musclesubstitution. Training with a pressure biofeedback unit in a supine position is often helpful,but as soon as possible the training must bedone in weight-bearing and functional postures.When the patient can successfully facilitate transversus abdominis, the next stage is to facilitatebilateral activation of lumbar multifidus, with cocontraction of transversus abdominis while maintaining lumbar spine neutral and controlling lateralcostal diaphragmatic breathing (O'Sullivan 2000).
Contractions of the local muscles should beperformed as a low load hold, and if globalmuscle substitution or fatigue occurs the patientmust stop the activity. Training requires great concentration and should be performed at least oncea day in a quiet environment. The patient beginsby holding the contraction for 10 seconds (or lessif very weak) and gradually tries to increase thelength of low-level hold up to 60 seconds.
Secondary training
This phase of motor training is focused on controlling the particular movements that give theteenager pain, or where they feel vulnerable.Initially training is done in lumbar spine neutraland later progresses to training during normallumbar spine movement. Adolescents need theexercises to be interesting and challenging, sothat the use of equipment such as wobble cushions, gymnastic balls and long D-rolls is oftensuccessful. Training must also encompass anysporting or recreational activities in which theteenager participates, and stabilizing exercises
MANAGEMENT OF THE HYPERMOBILE ADOLESCENT 57
are given to maintain intersegmental control atdifferent speeds of motion and sudden changesof direction.
CERVICAL SPINE - ACUTEWRY NECK
An acute torticollis (wry neck) is a common problem in those with hypermobility and often startsin adolescence. It is a painful unilateral conditionthat often manifests on rising in the morning,particularly in teenagers who sleep prone withtheir head rotated and extended. A sudden movement of the head can also cause the neck to become'stuck'. These individuals have poor control oftheir deep neck stabilizing muscles, so that asudden overstretching of the neck may causepartial subluxation of the facets, or torn musclesor ligaments (Beighton et al. 1989c).
The condition is characterized by an antalgicposture of flexion and side flexion away from thepainful side. Movements towards the side of painare restricted and painful. There is spasm ofsternocleidomastoid and the scaleni muscles,and the articular pillar on the affected side maybe very tender to palpation.
An acute wry neck is often self-limiting, sothat the pain and muscle spasms ease on theirown, usually within a week or two. However, thecondition tends to be recurrent, so that episodesof 'locking' occur more frequently, last longer,and become more difficult to help. The pain andrestricted movement are debilitating, so that theindividual is unable to exercise, play sport, andmany normal daily activities are temporarilyimpossible.
Palpation of the apophyseal joints underlyingthe muscle spasm will reveal one or two jointsthat have become hypomobile and acutely tender.The joint stiffness and spasm usually respondwell to gentle manual treatment. The use of a vigorous thrust technique is unwise because of theexcessive laxity of the unaffected joints (Grieve1988a).Unless a therapist can confidently localize
a manipulative technique to the specific hypomobile segment in an otherwise hypermobile neck, athrust technique should be avoided as it maycause facet subluxation or overstretch soft tissues.
The most important aspect of managing anacute wry neck is the prevention of recurrences.This is done by specifically training the deep neckflexor muscles that control intersegmental movement in the cervical spine. Training starts with theteenager in supine, their occiput supported on afolded towel so that their neck is in a neutral position. They are taught to do a gentle nod of thehead to facilitate the deep neck flexors without substitution from the global stabilizers ofsternocleidomastoid and the scaleni. Training isenhanced by the use of a pressure biofeedbackunit. The emphasis is on precision and control, theaim being to produce a low-load contraction andhold for 10 seconds, repeated 10 times comfortably(lull 1997). Once good control in supine has beenachieved, they progress to working the deep neckflexors in functional positions such as sitting andstanding, and eventually in positions adoptedduring their daily activities and sporting pastimes.
In addition, it is important to incorporatepostural and scapular training. Poor patterns ofneuromuscular control in the shoulder girdlemuscles can create painful dysfunction in thecervical spine (Jull 2001). Posture should be corrected from the pelvis upwards, and includesattaining an optimal position for the lumbar andthoracic curves with good control of the scapula.Particular attention needs to be paid to the control of the middle and lower fibres of trapeziusand serratus anterior. Training of the scapularstabilizers should be low load, performed in apain-free range and performed short of fatigue.
Many adolescents with hypermobility havedifficulty in contracting the scapular stabilizersbecause of poor proprioception and kinaesthesia.Facilitation of the muscles can often be achievedwith the use of EMG biofeedback, visual feedbackfrom a mirror, taping, active assisted exercise andproprioceptive neuromuscular facilitation (PNF)patterning.
58 HYPERMOBILITY SYNDROME
HIP
One of the drawbacks of the Beighton scoringsystem for hypermobility is that it assessesmovements at specific joints and ignores otherjoints that often become symptomatic in hypermobility. The hip and shoulder are both ball andsocket joints that normally exhibit a large rangeof movement and may exhibit excessive range inhypermobile subjects, but do not feature on theBeighton scoring system.
A problem encountered by hypermobile adolescents is a snapping or clicking hip. This candevelop secondary to intra- or extra-articularcauses. Intra-articular causes include loosebodies, a labral tear, osteocartilaginous exostosisand synovial chondromatosis (Micheli 1983).Thecommonest extra-articular cause of a clicking hipis the snapping of the iliotibial band over thegreater trochanter. Other soft tissue causes arethe iliopsoas tendon over the iliopectineal eminence, the iliofemoral ligaments over the femoralhead, and the long head of biceps over the ischialtuberosity (Sanders and Nemeth 1996).
Although a clicking hip is a common phenomenon in a hypermobile adolescent the click mayor may not be associated with pain (Sanders andNemeth 1996). In some cases the click is causedby excessive femoral head translation (in an anterior or posterior direction) that is associated withpoor control of the muscles of the hip and pelvis.Excessive anterior femoral glide occurs whenthere is tightness of the posterior capsule andduring flexion the femoral head moves anteriorly(Sahrmann 2002). It is often a feature in thosewith a sway-back posture who stand in posturalhip extension. Anterior femoral glide can beobserved when the supine patient performs hipflexion or a straight-leg raise. Hip flexion may berestricted or painful at about 90°, and a click maybe reproduced when the individual moves theleg actively from a flexed position to neutral. Thepain and click can often be reduced by the therapist placing a posteriorly directed force on thefemoral head.
The problem is managed by addressing themuscle imbalances of the hip, pelvis and lumbarspine. Those with an anterior femoral glide oftenhave a weak iliopsoas (particularly if they standin postural hip extension), weak gluteus mediusand maximus and tight hamstrings. It can also beassociated with overactivity of tensor fascia lataand a tight iliotibial band.
When rehabilitating the hip in a hypermobileadolescent, closed chain exercise is preferablebecause the weight-bearing component stimulates the mechanoreceptors around the joint,improving muscular contraction. Small rangeextension in supine with the leg over the sideof the bed, the knee flexed to 90° and the foot onthe floor is an effective way of facilitating gluteusmedius and maximus (Carr and Shepherd 1982).As soon as is viable, the muscles should be exercised as closely as possible to their functional andsporting activities. Retraining the hip musclesmust also include an evaluation of timing ofmuscle contraction and coordination in walkinggait and running if the teenager plays sport.
SHOULDER
The shoulder is the most mobile joint in the body,but its greater flexibility is at the expense ofstability. Shoulders that are quite lax may becompletely stable, whereas those without majorlaxity can become unstable. Gymnasts may haveextreme shoulder flexibility but have sufficientstability to allow them to perform compromising movements such as a unilateral handstand.However, those with generalized hypermobilitymay be predisposed to shoulder instability.
Glenohumeral instability can range from avague sense of loss of shoulder function and control to a frank instability due to a traumatic dislocation. Atraumatic instability of the shoulder canbecome symptomatic in adolescence and is seenmore commonly in girls than boys. The individual may have had repeated episodes of recurrenttransient subtle subluxations which eventually
MANAGEMENT OF THE HYPERMOBILE ADOLESCENT 59
progress to atraumatic dislocations. Some hypermobile adolescents are able to dislocate or subluxtheir shoulders voluntarily, and sometimes dothis as a 'party trick'. The condition can be unilateral, but is often bilateral in those with excessiveligamentous laxity.
There are a number of reasons why hyperrnobility can predispose to instability. An extensivejoint capsule may allow humeroscapular positions outside the range of balance stability, andpoor neuromuscular control may fail to positionthe scapula to balance the net humeral joint reaction force. An excessively compliant capsule withrelatively weak rotator cuff muscles will alsoreduce the stability of the joint. The instability ismost prevalent in mid-range positions and activities of daily living, so that simple actions such asputting on a coat or reaching for a pen can causethe shoulder to sublux.
When examining the hypermobile adolescentwith suspected instability it is essential to assessevery position where they feel vulnerable or as ifthe shoulder 'will go out of place'. Jerking, clickingand clunking are noted, and the scapula positionobserved at the point in range where the instability is dominant. Faulty humeroscapular patternsin combination with poor rotator cuff control areusually the key elements. Neuromuscular controlcannot be restored surgically, and these patientsrequire intensive rehabilitation and muscle training to restore normal functional stability.
The patient requires a well constituted, prolonged reconditioning programme that is tailoredspecifically to their neuromuscular dysfunction.There are two aspects to muscle retraining of theglenohumeral joint. First, the rotator cuff, whichcompresses the humeral head into the glenoid,must be strengthened, and second, stability isaided by regaining neuromuscular control ofhumeroscapular positions. Stability must beachieved in all glenohumeral positions, withparticular emphasis on those positions where thepatient feels vulnerable. It can take severalmonths of conscientiously performing a qualityprogramme for full stability to be achieved. Some
teenagers may need emotional support or counselling to help them understand that surgery isunlikely to be helpful, and that reduction ofsymptoms will only be possible through theirown hard work. They must be encouraged to stopvoluntarily subluxing or popping their shouldersout, and try to avoid activities and positions thatthreaten their shoulder's stability.
Other shoulder conditions, such as impingement, can occur secondarily to instability andthis can complicate the clinical picture.
Facilitation of the scapular stabilizers and rotator cuff may be enhanced with the use of EMGbiofeedback, PNF patterning and the use ofmirrors and taping. Exercises in weight-bearingwill also help to improve proprioception.
KNEE
Knee pain is a common manifestation in adolescents, particularly those with hyperrnobility.Twenty-five per cent of the population suffers frompatellofemoral pain at some time. in their lives(McConnell and Fulkerson 1996t and it is particularly common in the athletic population and inthose with hypermobility.
Anterior knee pain
The causes of patellofemoral pain are multifactorial and can be either structural or non-structural.Structural factors include femoral anteversion,increased Q angle, patella alta, patella baja, genuvalgum, genu varum, excessive foot pronationand genu recurvatum (Malek and Mangine 1981twhich can affect the balance of the soft tissuessurrounding the patella. The latter two are common clinical features of hypermobility which willmake the individual more susceptible to anteriorknee pain.
An alteration in the balance of soft tissuestructures that surround the patella is a majorcontributory factor, as movement of the patella iscontrolled by this and the shape of the articular
60 HYPERMOBILITY SYNDROME
surfaces and the supporting muscles. Malalignment of the patella due to biomechanical faultsaffects the tracking of the patella during kneemovements. This alters forces through the joint,which can cause damage to the articular cartilage. The articular cartilage is avascular andaneural, so that when degeneration occurs in thedeep and middle layers of the cartilage there arechanges in the energy absorption capacity of thatcartilage. This results in transference of weightfrom the articular cartilage to the richly innervated subchondral bone, and hence an increasein intraosseous pressure. Degenerative changesin the superficial layer of cartilage can irritate thesynovium, causing synovitis and pain (Fulkersonand Hungerford 1990).
During the growth spurt, the muscles and softtissues can become relatively tight and a decreasein flexibility of the lateral retinaculum, hamstrings, rectus femoris, gastrocnemius, soleus andtensor fascia lata (TFL) can adversely affect thetracking of the patella and become a trigger for theonset of symptoms. At the start of knee flexion,if the lateral retinaculum is short it comes understress and the patella is drawn into the trochlea.The tension increases further as the iliotibial band(lTB) moves posterior to the epicondyle of thefemur. As knee flexion increases the ITB pullsposteriorly on the already shortened retinaculum.These changes in the soft tissues cause lateraltracking and a lateral tilt of the patella (Fulkersonand Hungerford 1990). Vastus medialis oblique(VMO) is a dynamic medial stabilizer of thepatella, and if it weakens it is unable to resist thepull of any tight lateral structures.
Episodic joint effusions can be a feature ofhypermobility syndrome. VMO is inhibited byjoint effusion (Spencer et al. 1984) and, when present, individuals rapidly develop weakness ofVMO, which becomes only phasically active, sothat abnormal patellar tracking occurs. Pelvicmuscle imbalances and abnormal gait patterns canalso lead to patellofemoral problems. Examination of anterior knee pain in hypermobilityrequires an in-depth assessment of the length,
strength and control of the muscles and soft tissues that surround the patella, so that appropriaterehabilitation programmes can be implementedthat address the relevant imbalances.
Patellofemoral instability
Patellofemoral instability is a variant ofpatellofemoral pain syndromes. It is more common in females, those with generalized hypermobility, and those who have patella alta, a Qangle greater than 20°, dysplasia of the trochleaand patella, and hyperextension of the knee (lnsall1979, Hughston 1989).The patella may sublux laterally or dislocate, and the patient exhibits apprehension when the patella is passively movedlaterally. Patellar instability can be devastating tothe articular cartilage, although Stanitski (1995)found that hypermobile individuals were 2.5times less likely to suffer articular surface damage with patellar dislocation.
Physiotherapy intervention aimed at trying tooptimize biomechanical alignment and addressing the soft tissue imbalances of the patella isoften successful. Treatment includes a strengthening programme for VMO and exercises toimprove pelvic stability. Those with hypermobility also need to emphasize exercises aimed atimproving proprioception and kinaesthesia.
Genu recurvatum
Excessive hyperextension of the knee can result innipping or trapping of the infrapatellar fat pad inthe knee. The patient presents with tendernessand puffiness around the inferior pole of thepatella. The pain is worse on standing, particularly if the individual hyperextends the knee,and is reproduced by extension overpressure.Malalignment of the patella can cause the inferiorpole to be displaced posteriorly, so that the fat padis compressed. Retraining the quadriceps, hamstrings and stability muscles of the pelvis is a keyfeature in the management of this problem and isbest performed in weight-bearing positions to
MANAGEMENT OF THE HYPERMOBILE ADOLESCENT 61
ensure improvement in the control of knee hyperextension in a functional position. Strenuous workof the quadriceps alone could simply reinforce thehyperextension of the knee and exacerbate theproblem.
FOOT
Abnormal pronation of the foot is defined as anabnormal pronation of the entire foot which occursat the subtalar joint (Wilson 1906),and it is responsible for more chronic low-grade symptomatologyin the lower leg than any other type of foot problem (Root et al. 1977). During locomotion the footmay function around an abnormally pronatedposition, or may move in the direction of pronationat the time when it should be supinating. There area number of common congenital and developmental foot deformities which are compensated for byabnormal pronation. The commoner deformitiesinclude forefoot varus, rearfoot varus and anklejoint equinus. There are also a number of structuraldeformities extrinsic to the foot compensated forby abnormal pronation, and these include tibiavara, internal tibial torsion, internal femoraltorsion, congenitally shortened gastroc-soleus andhamstrings. In addition to any congenital or developmental deformities individuals with generalized hypermobility have a greater tendency tooverpronation owing to the laxity of their ligaments, poor control of the phasic muscles whichstabilize during gait, and the 'creep' effect thatmakes soft tissues elongate under load in a weightbearing position (Root et a!. 1977).
Excessive pronation increases forces across thefoot and can lead to symptomatology and evensubluxation of some of the joints. A stable foot isessential, and instability created by overpronation readily affects other joints. As the subtalarjoint pronates it causes internal rotation of thetibia and femur, thereby creating abnormal function in the lower limb and pelvis. Normal footfunction in an individual with generalizedhypermobility will be compromised if they have
an unstable foot, and this will have a detrimentaleffect on their ability to stabilize other joints ofthe lower limb and pelvis.
When the bones of the foot become unstable,the forces across the bones create movement of thejoints in the direction of the application of thoseforces acting upon them. If these forces producejoint movement they increase hypermobility. Theabnormal shifting of the weight-bearing bonesof the foot causes excessive shearing betweenthe bones and the surrounding soft tissues, andadaptive changes occur in both the bones and thesoft tissues. In the hypermobile adolescent thebone adapts rapidly by changing shape, and newbone is laid down in accordance with requirementsof function and in accordance with the transmission of forces through the bone. As growth occursrapidly during adolescence, permanent osseousdeformity can occur.
During the gait cycle, when the foot first hitsthe ground it needs to become a mobile adaptorto make full ground contact, and this is normallythe time when the foot pronates. Further propulsion requires the foot to become a rigid lever, andthe tarsal bones must become locked togetherby the osseous locking mechanisms which occuras the foot is supinated. This action stabilizes themajor functional joints of the foot. The stabilityof the foot is reinforced by the contraction of thestance phase muscles (Root et al. 1977). Theintegrity of the joints is maintained and the shearforces are reduced to prevent symptomatology.
If the foot remains abnormally pronated during propulsion the normal osseous locking mechanisms within the tarsus are less efficient. Thetarsus becomes unstable and the phasic musclesare unable to sufficiently stabilize. As the heellifts the forces supported by the forefoot causethe individual bones to move abnormally relativeto each other and joint stability is diminished.The abnormal forces may eventually cause thejoints to sublux.
Hypermobility of the foot has been linkedto many different clinical foot disorders, andcommon problems include hyperkeratoses on the
82 HYPERMOBILITY SYNDROME
toes and plantar surfaces of the feet, metatarsalgia, plantar fasciitis, hallux abductovarus, halluxlimitus, hallux rigidus, muscle fatigue, and strainsin the lower leg (Root et al. 1977). Many of theseproblems start to become symptomatic duringadolescence owing to the rapid growth phase andthe greater body weight, which increases theforces sustained by the feet.
Some hypermobile adolescents may be helpedby an exerciseprogramme aimed at improving thefunction of the muscles of the lower limb, butothers require some form of orthosis that will helpto control the hypermobility and improve the stability of the foot. The prescription of an orthoticfor an adolescent with hypermobility must takeinto account any congenital or developmentaldeformity, as well as the poor proprioception andskin fragility that are a feature of hypermobility.If an orthosis made of a soft, flexible material issupplied, it can make joint proprioception andkinaesthesia more difficult for the hypermobileadolescent, and this can be improved by the useof a firmer material or rigid device. However,some hypermobile individuals are unable totolerate a rigid device because of the fragility oftheir tissues, and require appropriate materials tocounteract this.
Abnormal pronation is greater in runningowing to the increase in ground reaction forcesand an increase in functional limb varus. Ahypermobile adolescent may therefore be symptom free when walking, but complain of pain andmuscle strains when running. The use of well fitting, supportive footwear that is appropriate tothe particular sport is essential, especially duringthe rapid growth phase.
PSYCHOSOCIAL FACTORS
The physical changes that occur during adolescence are accompanied by emotional and psychological development, which can make it aconfusing and difficult time for a teenager. Anadolescent with hypermobility will not necessarily
experience symptoms, but the onset of unexplained pain may be frightening and can causeadditional emotional distress. It is helpful foradolescents to understand the nature of theirproblem and to learn that it can be managedsuccessfully. The development of fear / avoidancebehaviour in those who have hypermobility syndrome needs to be identified and addressed. Ifa movement or activity becomes painful an individual may avoid performing various actionsbecause they fear they are doing irreversible damage to their body. As movement patterns alter,elements within the musculoskeletal systemadapt so that there is greater dysfunction and painis provoked more easily. In turn, the individualrestricts his activities further and a cycle developswhich becomes increasingly difficult to change.An understanding of the physiological conditionand reassurance that it is important to maintain asnormal a lifestyle as possible is essential in theprevention of chronic pain.
Compliance
Successful management of the hypermobileadolescent is dependent on the compliance ofthe individual.
Compliance can be difficult and challenging toachieve in a teenager. At our clinic we havefound the following points helpful:
1. Listen carefully to the patient and ensure thatyou fully understand the extent and natureof his or her problems. It is essential to realizethe impact of their problems on school, socialand home life. The teenager will have greaterconfidence in you if they think you understand their problem.
2. Talk directly to the patient and keep eye contact. Teenagers under 16years of age should beaccompanied by a parent or guardian, but donot ignore the adolescent and talk solely to theadult. It is important to build a good basis forcommunication with the teenager from thestart. If the parent answers questions for the
MANAGEMENT OFTHE HYPERMOBILE ADOLESCENT 83
adolescent, gently tell them that you wouldlike the child to answer, and that they will begiven an opportunity to comment or askquestions during the examination.
3. Explain the problem clearly to both the patientand their parent. Teenagers are intelligent andhave a natural curiosity. They are more likelyto follow an exercise regimen and other lifestyle changes if they understand the need forand the likely benefits of a managementprogramme.
4. A positive attitude from the physiotherapist isessential. The adolescent must understandthat they can take back control of their problem themselves if they are prepared to put thework in first. Emphasize that many hypermobile adolescents keep symptoms at bay andpartake in the same activities as their peersonce they have trained the appropriate musclegroups and improved their exercise tolerance.
5. Set realistic goals for exercise programmes,general fitness and lifestyle adjustments. Giveencouragement and praise achievement.
6. Exercisesgiven as homework must be pain free.If an exercise hurts, the teenager is unlikely tocontinue with it and quickly loses confidence inthe rehabilitation strategy. It is usually possibleto find an exercise that is not painful to perform. We rarely give a patient more than threeexercises at one time and expect that they willhave achieved a pre-agreed target by their nextattendance. Once a patient can do an exercisewell it is modified or replaced with one that ismore challenging.
7. Make the exercise fun and interactive. Wehavefound the use of EMG and pressure biofeedback, jelly cushions, wobble boards, gymnasticballs and other equipment effective and popular with teenagers.
8. Remember that exercises take time to work.Explain this to the patient and set a realistictimescale for when you would expect to seesome improvement in symptoms. During thistime it is quite normal to have some days thatare not as good as others, and encourage the
adolescent to continue with the programme onboth good and bad days.
9. When dealing with the anxious parents of ahypermobile teenager encourage them not tobecome overprotective, and stress that it isimportant and healthy for their child to do asmany normal activities as possible. If a particular activity presents a recurring problem, discuss ways of modifying it so that the adolescentcan continue. As the overall condition of theteenager improves with treatment and exercise,many activities that were once difficult orinhibited by pain become pain free.
SPORT
Adolescents with hypermobility should beencouraged to take regular exercise and playsport. The benefits of sport for the hypermobile include improving cardiovascular fitness,improvements in muscle strength and control,coordination and proprioception, and a feeling ofwellbeing. There is no one particular form ofexercise that has been proved to be superior toany other for those with hypermobility, but it isimportant that it is an activity or form of exercisethat the teenager enjoys and feels comfortable doing. Although swimming is excellent exercise for the hypermobile, it is advisable to alsoinclude some form of regular exercise that isweight-bearing to increase bone loading andimprove proprioception. There are many benefitsof playing team sports and taking part in exercisewith other adolescents, but playing contact sportssuch as rugby may be inadvisable for some individuals with hypermobility syndrome. Those withhypermobility will need a training programmethat includes muscle control work specific totheir individual needs and the physical demandsof their particular sport. If sport or exercise is painful, the adolescent should be carefully assessed toidentify any specific training needs.
Liaising with the individual's PE teachers,sports coaches or trainers can be useful. It is
64 HYPERMOBILITY SYNDROME
important that those involved with teaching orcoaching an adolescent who has hypermobilityare aware of the condition and watch out forpotential problems. It is helpful if hypermobileadolescents are able to take part in sport at schoolwith their friends and peers.
LIFESTYLE ADAPTATIONS
Adaptations and changes in lifestyle and habitscan make everyday activities more comfortable.
Case study
A 15-year-old student presented with a 2-year historyof problems. She gave a history of pain in the interscapulararea which spread to the neck and low back. A year afterthe onset of her problem she was also getting pain in bothhips and knees. She had a series of investigations.including X-rays. blood tests. MRI and CT scans. whichwere all normal. Three months after the onset of symptomsshe was advised to stop all sport and any activities thatexacerbated her condition. The adolescent had receivedtreatment (exercise. manipulation. traction. medication andelectrotherapy) from a variety of practitioners withno success. and her problem had become so severe that inthe previous 3 months she had only felt well enough toattend school on 12 occasions. She was referred tophysiotherapy by a consultant. but was reluctant to comefor treatment as previous treatments had been unsuccessfuland had even worsened her symptoms.
On examination she had poor posture. with obvious lackof control of the spinal and pelvic stabilizers. Shestood with both knees in hyperextension and with bilateralpronated feet. The head was in a forward position. she hadan increased thoracic kyphosis. and poor control of thescapular stabilizers. Her spinal movements were generallygood and she was able to bend forward and place bothhands flat on the floor. However, she had difficulty inreturning to the upright position and had to place her handson her thighs to assist her return to upright standing. Shedemonstrated excessive flexibility in other joints and scored7/9 on the Beighton scale.
The range of neck movements was also good. but shehad particular difficulty in returning the extended neck toa neutral position and had to use a hand to support herneck. Neurological examination was normal. She washypersensitive and jumpy on palpation of the spine.
ManagementShe was given a careful explanation of JHS and, indiscussion with the girl and her parents. a managementstrategy was developed. She was anxious about tryingany form of exercise as this had always aggravated hersymptoms in the past. We explained that the exercisesshould be pain free while she was performing them. Wealso told her that she would start to notice a difference inher symptoms after about a month. but it would take
The use of a good backpack to carry schoolworkand other items will reduce the stresses on thespine and upper limbs. Study positions at homeand school are frequently triggers for the onset ofpain. Advice on sitting positions for schoolworkand studying are essential. The provision ofitems such as a supportive adjustable chair, writing slopes, copyholders, pens with a thick gripand ergonomic keyboards may be helpful. However, even when a work or study position is optimal, prolonged sitting can cause discomfort, andover a period of time soft tissue adaptations
approximately 8 months of training to regain full musclecontrol. On the first attendance she was taught low-loadabdominal bracing with the help of a pressurebiofeedback. On her second attendance there was noimprovement in her symptoms but she could do specificdeep abdominal bracing and repeat It several timeswithout pain. She was praised for her achievement. andrewarded with a more challenging exercise for the deepabdominal muscles. She was also taught to contract thedeep neck flexors and loaned a pressure biofeedbackwith the aim of improving the deep neck flexor controlover the next week. During the following weeks sheworked hard to improve trunk stability. and treatment wasexercise and advice based. After 5 weeks she reportedthat she had less pain and could study for longer periodswithout having to lie down. At the end of 8 weeks she hadmanaged to go to school for 3 weeks without taking a dayoff. At this point specific soft tissue mobilizations wereused to treat trigger points in the upper fibres of trapezius.and she was taught scapular stabilizing exercises.
The trunk stability exercises were progressed tobecome more challenging and she was loaned variouspieces of equipment to make the work interesting andfun. She gradually gained more confidence and beganactivities aimed at improving her cardiovascular fitness.Initially she started with a brisk 10-minute daily walk andquickly progressed to swimming on a regular basis. Fivemonths after the onset of treatment she reported thatshe had had no pain in the previous 2 weeks and hadreturned to most of her normal activities.
CommentAfter discussion with the patient's parents. it was notedthat the onset of symptoms correlated with a growthspurt. Early on. the patient had been advised to stop allphysical activity and consequently had developedconsiderable muscle weakness, particularly of thestabilizing muscles of the spine and pelvis. The spread ofsymptoms and lack of improvement with varioustreatments had caused great anxiety to the girl and herfamily. The teenager had been dismissed by some ashaving 'growing pains'. or told that it was 'all in themind'. This is a scenario that we see all too often at ourclinic
MANAGEMENT OF THE HYPERMOBILE ADOLESCENT 65
can occur. Therefore, advice on regular breaksand gentle stretching exercises to maintain rangeof movement is useful. Even though a hypermobile teenager has an excessive range of movement, it is important that they maintain theirnormal range of movement and have good control of movement throughout their hypermobilerange.
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