We have followed the natural progress of newborn infants in whom ultrasound examination showed abnormalities in hips which appeared to be clinically normal. Over six years we saw 306 such children out of 9952 examined (31 per 1000 live births). The examination was repeated at two to three months and those who still showed an abnormality were followed up further. At four to five months a standard radiograph was obtained, and treatment began if this and another ultrasound scan were both abnormal. At this stage, 291 infants had normal hips. In the 15 infants with abnormal hips there was no pronounced deterioration, none developed a frank dislocation, and all became normal after treatment in an abduction splint. Newborn infants with abnormal and suspicious ultrasound findings who are normal on clinical examination do not need treatment from birth; most of these hips will settle spontaneously. Treatment can be postponed until the age of four to five months unless clinical instability develops or ultrasound shows dislocation. The criteria for treatment should be based on measurements by both ultrasound and radiography: both should show an abnormality before intervention is considered necessary

Aims

This study presents the long-term survivorship, risk factors for prosthesis survival, and an assessment of the long-term effects of changes in surgical technique in a large series of patients treated by metal-on-metal (MoM) hip resurfacing arthroplasty (HRA).

1. Paralytic dislocation of the hip in spina bifida generally requires reduction and iliopsoas transfer. The muscle transfer ensures that the hip remains reduced, lessens the need for calipers and prevents progressive flexion deformity. In addition, varus and rotation osteotomy of the femur and innominate osteotomy are sometimes required. Varus and rotation osteotomy alone is indicated if the psoas is not strong enough for transfer. The age for reduction of dislocated hips and muscle transfer has been reduced to eight months as experience and confidence has been gained. 2. Flexion deformity is best prevented by early iliopsoas transfer. An anterior release operation is occasionally indicated when there is flexion deformity and a weak psoas muscle. This procedure, alone or supplemented by extension osteotomy, may be necessary to correct severe flexion deformity in children seen late. 3. Lateral rotation deformity of the hip may be caused by unbalanced iliopsoas action or the unbalanced action, or contracture, of the short lateral rotator muscles. If the deformity is sufficient to make the gait bizarre, or if it is difficult to fit a caliper, then soft-tissue operations as described are of value. 4. Abduction deformity can be corrected by division of the unopposed or contracted abductors

We have evaluated the effect of the use of ultrasound in determining the initiation of treatment in neonatal instability of the hip. A total of 99 newborn infants (1.5% of all live births) with neonatal hip instability did not have treatment from birth, but were re-examined at eight to 15 days. In the 31 who had persisting clinical instability and ultrasound abnormality, treatment was then started with a Frejka pillow. The hips in the remaining 68 infants showed spontaneous clinical stabilisation and improvement of the ultrasound findings. Treatment was therefore withheld. There was a marked trend towards normal development in mildly unstable hips, whereas no hips with severe instability did so spontaneously. Further follow-up showed normal development in all the hips which had been treated, and in all except five of the 68 untreated infants. These five infants showed persistent hip dysplasia on both ultrasound and radiological examination at four to five months of age. Treatment with an abduction splint was then started and their hips developed normally. Ultrasound is very useful in deciding on treatment if the examiners have adequate experience with the method. Its use substantially reduces the rate of treatment. Spontaneous resolution occurred in more than half of the unstable hips. Since five of the untreated infants developed hip dysplasia a strict follow-up is essential to identify and treat these cases

1. The examination of fifty-one infants presenting signs of unilateral dysplasia (preluxation) of the hip disclosed the existence of an abduction-contracture in the opposite "normal" hip. 2. The abduction-contracture was not infrequently found in the newborn, but seemed to attract attention mostly between the second and fifth month of life. It was seldom found after the sixth month. 3. The dysplasia in the contralateral hip showed the usual features. 4. The relationship between the degree of abduction-contracture and the degree of dysplasia was a direct one only occasionally; in most cases they seemed unrelated to each other. 5. Observation of these patients showed that the abduction-contracture followed a constant course towards gradual and spontaneous regression. The dysplasia progressed in one of the following directions: spontaneous recovery, rapid or slow recovery with treatment by abduction splint, subluxation, or true dislocation. 6. It is submitted that the coexistence of unilateral dysplasia of the hip and abduction-contracture in the opposite hip is not fortuitous. It is believed that the abduction-contracture determines the development of the dysplasia in the opposite hip through the faulty mechanics caused by "fixed pelvic obliquity.". 7. The discovery of unilateral abduction-contracture soon after birth should be a warning that dysplasia may develop in the opposite hip. A careful watch should therefore be kept for signs of abduction-contracture and for the later development of dysplasia

Aims

The aim of this study was to report the outcomes of different treatment options for glenoid loosening following reverse shoulder arthroplasty (RSA) at a minimum follow-up of two years.

Aims

The aim of this study was to evaluate the accuracy of implant placement when using robotic assistance during total hip arthroplasty (THA).

Operative release for entrapment of the suprascapular nerve was carried out in 35 patients. They were assessed at an average of 30 months (12 to 98) after operation using the functional shoulder score devised by Constant and Murley. The average age at the time of surgery was 40 years (17 to 67). Entrapment was due to injury in ten patients and no cause was found in three; 34 had diffuse posterolateral shoulder pain. The strength of abduction was reduced in all the patients. The average Constant score, unadjusted for age or gender, before operative release was 47% (28 to 53). In 25 of the patients both the supraspinatus and infraspinatus muscles were atrophied and seven had isolated atrophy of the infraspinatus muscle. The average conduction time from Erb’s point to the supraspinatus muscle and to the infraspinatus muscle was 5.7 ms (2.8 to 12.8) and 7.4 ms (3.4 to 13.4), respectively. In two patients MRI revealed a ganglion in the infraspinatus fossa and, in another, a complete rupture of the rotator cuff. The average time from the onset of symptoms to operation was ten months (3 to 36). A posterior approach was advocated. The average Constant score, after operative release, unadjusted for age or gender was 77% (35 to 91). The overall result was excellent in ten of the patients, very good in seven, good in 14, fair in two, and poor in two. The symptomatic and functional outcome in our series confirmed the usefulness and safety of operative decompression for entrapment of the suprascapular nerve

Aims

Severe acetabular bone loss and pelvic discontinuity (PD) present particular challenges in revision total hip arthroplasty. To deal with such complex situations, cup-cage reconstruction has emerged as an option for treating this situation. We aimed to examine our success in using this technique for these anatomical problems.

1 . The extensor assembly of the fingers consists of the central tendon joined by three pairs of components: a) the retinacular ligaments, which link the movements of the interphalangeal joints; b) the "wing" tendons, a lumbrical on the radial side, and usually a palmar interosseous on the ulnar side; c) the phalangeal tendons, usually dorsal interossei. 2. The retinacular ligaments are relaxed in full extension of the proximal interphalangeal joints and are, in this position, unable to extend the distal joints fully. This is because the interphalangeal joint surfaces are eccentric. 3. The pull of the wing tendons alters the shape of the extensor expansion and transfers the pull of the long extensor tendon from the base of the middle phalanx to the base of the distal phalanx, thus enabling full extension of the distal joint to be powerfully achieved. 4. The action of the lumbrical muscle, as an extensor of the interphalangeal joint, is demonstrated by a diagram showing its site and length in the various positions of the finger, calculated from the known excursions of the tendons. This is consistent with the observations on action potentials. 5. The phalangeal tendons of the dorsal interossei have a bifid insertion, a) into the phalangeal tubercle at the base of the proximal phalanx, and b) into the transverse band, and hence to the central tendon. The muscle acts at one or both of these attachments, according to the positions of the metacarpo-phalangeal and interphalangeal joints, in its varying functions of flexion, abduction and hyperextension. Finally an explanation of the deformity of clawing in ulnar palsy is given

Aims

Scapular notching is a frequently observed radiographic phenomenon in reverse shoulder arthroplasty (RSA), signifying impingement of components. The purposes of this study were to evaluate the effect of glenoid component size and glenosphere type on impingement-free range of movement (ROM) for extension and internal and external rotation in a virtual RSA model, and to determine the optimal configuration to reduce the incidence of friction-type scapular notching.

Drawing upon a total experience of 450 hips affected by established congenital dislocation or subluxation, the author presents the long-term results in 177 hips treated for the first time between the ages of nine months and three and a half years, in support of his contention that surgical endeavour should in the first place be directed towards the limbus and upper end of femur rather than the acetabulum. The 144 patients, all treated on lines previously described in this journal (Scott 1953; Somerville 1953a, b; Somerville and Scott 1957), have now been followed up annually for between ten and twenty-five years, both hips receiving equal scrutiny. In brief, the routine has consisted of arthrography, excision of any limbus shown to be inverted, reduction by traction in abduction, and rotation osteotomy of 70 degrees. The addition of 10 to 15 degrees of varus was found beneficial and has become routine. Some hips required secondary procedures, and regret is expressed that these were not carried out sooner. The upper age at which recovery of the acetabulum may occur was found to be much higher than generally supposed, with a critical period between eleven and fourteen. The main conclusion is that in the great majority of cases first seen in this particular age group, improvement of the mechanics of the joint, especially by attention to the upper end of femur, leads to satisfactory development of the acetabulum and good functional results, at least up to early adult life

The results of a long-term review of 102 hips in eighty-seven patients with Perthes' disease are described, the mean follow-up interval being seventeen years. All had been treated by an extremely rigorous conservative regime in which the patients were kept in hospital for an average period of twenty-six months, during which time they were confined to bed with the legs in wide abduction, first in traction and later in "broomstick" plasters to ensure "containment" of the femoral head. The patients were assessed by the joint clincial and radiological method described by Ratliff (1956). The results were very satisfactory, with only 2 per cent poor results and 10 per cent fair. The remaining 88 per cent were good. The radiological results at the end of treatment have also been compared with control series described by Catterall (1972) and with the osteotomy series of Lloyd-Roberts, Catterall and Salamon (1976). From this it appears that the described regime offers no benefit compared with the natural history in Catterall's Groups I and II, and in Group III the results were only marginally better than those following osteotomy. In Group IV cases, however, where the femoral head was totally involved, the benefit was important, and since these are the cases which carry the worst natural prognosis it is suggested that the use of the method described in such instances must be seriously considered in spite of its social disadvantages. The theoretical implications of the findings are considered, and it is concluded that the benefits of the method cannot be ascribed wholly to the application of the "containment" principle

1. The hip joint usually acts as the fulcrum of a lever system. 2. The centre of gravity of supported parts, which is usually medial to the hip joint, exerts a rotational effect upon the pelvis. If pelvic position is to be maintained this force must be counterbalanced by hip muscles. 3. The force transmitted by the hip joint is the sum of the supported body weight and the tension in the balancing muscles. This force often exceeds the total weight of the body. 4. In some circumstances the loss of one pound of body weight relieves the hip joint of three pounds pressure. 5. A long femoral neck is an advantage to hip function, but in arthroplasty this must not lead to mechanical failure such as breaking or loosening of the prosthesis, or fracture of the bone. 6. Medial displacement of the femoral head upon the pelvis may cause a great decrease in joint pressure, but medial displacement alone of the shaft upon the head and neck does not influence the mechanics of the joint. 7. The position of the centre of gravity of supported parts is easily altered by slight variations in spinal position. Great changes in hip joint pressure are caused by small coronal spinal movements, but the advantage to man of being able to walk with the eyes steady outweighs the mechanical disadvantage to which his hip is subjected. 8. A femoral abduction osteotomy improves the mechanics of a hip joint deformed in adduction. 9. A walking stick or a crutch is most helpful in relieving joint pressure and reducing the work done by hip muscles

1. The causes of pressure on the neuro-vascular bundle of the upper limb are many and varied. No one cause such as clavicular pressure can explain all cases. 2. Costo-clavicular pressure is not possible when there is a normal first rib and a normal thoracic outlet, but it is certainly a factor when the costo-clavicular interval is narrowed by the presence of a large cervical rib or an abnormal first thoracic rib. Clavicular pressure can act only during retraction and abduction, not in depression of the shoulder. 3. Temporary alterations in the radial pulse on movements of the shoulder in normal individuals are due to causes distal to the clavicle and have no relation to costo-clavicular pressure. 4. While irritation of sympathetic nerve fibres may explain the majority of cases of thrombosis, there are others in which clotting occurs in an aneurismal dilatation produced by pressure between the clavicle and the abnormal costal element. It is likely that the thrombosis occurs in an aneurism which has been present for some length of time. The cause of the aneurismal dilatation may be vaso-motor paralysis of a segment of the artery, ending distally at a point where a fresh intact leash of nerves is relayed to the vessel. 5. The importance of the scalenus anterior syndrome has been over-emphasised. If operative treatment is limited in all cases to anterior scalenotomy the results will be disappointing. 6. If operation is advised it should be performed without rigid and preconceived ideas, through an adequate incision, and with exploration wide enough to allow thorough investigation of the cause of pressure

Aims

Patient-specific instrumentation of total knee arthroplasty (TKA) is a technique permitting the targeting of individual kinematic alignment, but deviation from a neutral mechanical axis may have implications on implant fixation and therefore survivorship. The primary objective of this randomized controlled study was to compare the fixation of tibial components implanted with patient-specific instrumentation targeting kinematic alignment (KA+PSI) versus components placed using computer-assisted surgery targeting neutral mechanical alignment (MA+CAS). Tibial component migration measured by radiostereometric analysis was the primary outcome measure (compared longitudinally between groups and to published acceptable thresholds). Secondary outcome measures were inducible displacement after one year and patient-reported outcome measures (PROMS) over two years. The secondary objective was to assess the relationship between alignment and both tibial component migration and inducible displacement.

Aims

Open reduction is required following failed conservative treatment of developmental dysplasia of the hip (DDH). The Ludloff medial approach is commonly used, but poor results have been reported, with rates of the development of avascular necrosis (AVN) varying between 8% and 54%. This retrospective cohort study evaluates the long-term radiographic and clinical outcome of dislocated hips treated using this approach.