We have studied the beneficial effects of a hydroxyapatite (HA) coating on the prevention of the migration of wear debris along the implant-bone interface. We implanted a loaded HA-coated implant and a non-coated grit-blasted titanium alloy (Ti) implant in each distal femoral condyle of eight Labrador dogs. The test implant was surrounded by a gap communicating with the joint space and allowing access of joint fluid to the implant-bone interface. We injected polyethylene (PE) particles into the right knee three weeks after surgery and repeated this weekly for the following five weeks. The left knee received sham injections. The animals were killed eight weeks after surgery. Specimens from the implant-bone interface were examined under plain and polarised light. Only a few particles were found around HA-coated implants, but around Ti implants there was a large amount of particles. HA-coated implants had approximately 35% bone ingrowth, whereas Ti implants had virtually no bone ingrowth and were surrounded by a fibrous membrane. Our findings suggest that HA coating of implants is able to inhibit peri-implant migration of PE particles by creating a seal of tightly-bonded bone on the surface of the implant

Abstract

Nerve transfer has become a common and often effective reconstructive strategy for proximal and complex peripheral nerve injuries of the upper limb. This case-based discussion explores the principles and potential benefits of nerve transfer surgery and offers in-depth discussion of several established and valuable techniques including: motor transfer for elbow flexion after musculocutaneous nerve injury, deltoid reanimation for axillary nerve palsy, intrinsic re-innervation following proximal ulnar nerve repair, and critical sensory recovery despite non-reconstructable median nerve lesions.

We treated 50 patients with fractures of the waist of the scaphoid in a below-elbow plaster cast for up to 13 weeks. Displacement of the fragments was assessed independently by two observers using MRI and radiographs performed within two weeks of injury. The MRI assessments showed that only the measurement of sagittal translation of the fragments and an overall assessment of displacement had satisfactory inter- and intra-observer reproducibility and revealed that nine of the 50 fractures were displaced. Only three of the 49 fractures with adequate follow-up failed to unite, and all were displaced with more than 1 mm of translation in the sagittal plane. If the MRI assessment of displacement of the fracture was used as the measurement of choice, assessment of displacement on the initial scaphoid series of radiographs showed a sensitivity of between 33% and 47% and a positive predictive value of between 27% and 86%. Neither observer was able correctly to identify more than 33% to 47% of the displaced fractures from the plain radiographs. Although the overall assessment of displacement and gapping and translation in the coronal plane on the plain radiographs influenced the rate of union, none of these parameters identified all three fractures which failed to unite. We conclude that the assessment of displacement of scaphoid fractures on MRI can probably be used to assess the likelihood of union although the small number of nonunions limits the power of the study. In contrast, the assessment of displacement on routine radiography is inaccurate and of less value in predicting union

Over the 10-year period 1969 to 1978, 271 consecutive cases of congenital dislocation of the hip were diagnosed at birth. Standard anteroposterior radiographs of the pelvis were obtained routinely and were analysed retrospectively. The medial gap, a measure of the separation between the proximal femur and the pelvic wall, was found to be significantly increased in cases with unilateral or bilateral dislocation when compared to normal. A medial greater than five millimetres is indicative of femoral head displacement and is of value where the clinical diagnosis is uncertain. The rate of missed dislocation at birth was 0.6 cases per thousand. Treatment with the Malmo splint was the normal routine. The Pavlik harness was applied if splintage was poorly tolerated by the infant, or in the rare instance of limited hip abduction. Failure to maintain reduction by splintage occurred in 3.3 per cent. The incidence of pressure deformities of the femoral head was 2.95 per cent and there was a residual deformity in later childhood of 1.1 per cent. It is presumed that this lesion can be attributed to the effect of splintage and it was notably avoided in the later period of the review when greater mobility of the abducted hips was encouraged

We report the use of a new method of locked intramedullary flexible osteosynthesis (LIFO) in the treatment of 118 unstable fractures of the femur and tibia. The implant utilises a set of flexible pins with a separate locking device for their proximal ends. The LIFO system proved capable of stabilising unstable fractures, and most of the complications occurred during the early testing. At follow-up, 19 of 21 femoral fractures had healed; one become infected and one showed defective callus. Of the 78 tibial shaft fractures, five failed to consolidate and five had inadequate callus. Reaming of the tibial medullary canal was never necessary. Of 28 open fractures only one became infected. The system was most difficult to use in comminuted distal fractures of the tibia, with five failures of healing in 19 cases; these cases require considerable technical proficiency. The flexibility of the system appears to promote earlier consolidation of open fractures, and normal consolidation times for fractures with interfragmentary gaps of up to 10 to 12 mm. A comparative study of callus density in tibial fractures showed a mean improvement of 50 days in cases treated by the LIFO system compared with similar cases treated by rigid nailing

The histology and mechanics of leg lengthening by callus distraction were studied in 27 growing rabbits. Tibial diaphyses were subjected to subperiosteal osteotomy, held in a neutral position for 10 days and then slowly distracted at 0.25 mm/12 hours, using a dynamic external fixator. Radiographs showed that the gap became filled with callus having three distinct zones. Elongation appeared to occur in a central radiolucent zone; this was bounded by two sclerotic zones. Histologically, the radiolucent zone consisted of longitudinally arranged cartilage and fibrous tissue while the sclerotic zones were formed by fine cancellous bone. New bone occasionally contained islands of cartilage, suggesting it had been formed by endochondral ossification. After completion of distraction, the two sclerotic zones fused, shrank and were eventually absorbed, leaving tubular bone with a new cortex. When the periosteum had been removed at the operation, callus formation was markedly disturbed and there was failure of bone lengthening. Scraping of endosteum, in contrast, did not have a pronounced effect. These results suggest that the preservation of periosteum is essential if bone lengthening by callus distraction is to succeed, and that preservation of the periosteum is more important than careful corticotomy

Objectives

The medially spherical GMK Sphere (Medacta International AG, Castel San Pietro, Switzerland) total knee arthroplasty (TKA) was previously shown to accommodate lateral rollback while pivoting around a stable medial compartment, aiming to replicate native knee kinematics in which some coronal laxity, especially laterally, is also present. We assess coronal plane kinematics of the GMK Sphere and explore the occurrence and pattern of articular separation during static and dynamic activities.

We studied the cellular response to physeal distraction in the growth plates of skeletally immature rabbits. We used a new method of labelling and detection of proliferating cells with bromodeoxyuridine (BUdR) and an anti-BUdR antibody. The application of an external fixator but no distraction force produced no changes in the growth plates. After five days of distraction at a maximum force of 20 N, the growth plate became thicker, mainly because of an increase in the number of hypertrophic chondrocytes, but there was no evidence of increased cell proliferation. Recent fractures were seen at the junction of growth plate and metaphysis but the increase in bone length was insignificant. After ten days of distraction at the same maximum force, the chondrocyte columns had become disorganised and cell proliferation was significantly decreased. There was an increase in bone length due to distraction of the fracture gap. In this model, physeal distraction did not stimulate cell proliferation, but actually inhibited it. The apparent increase in growth-plate thickness produced by distraction is not due to increased cell production, but results from inhibition of endochondral ossification and the consequent accumulation of hypertrophic chondrocytes. Any growth after distraction depends on the ability of growth-plate chondrocytes to divide. The decrease in proliferative activity which we found after ten days of distraction suggests the need for caution in the use of such procedures in young children

Informed consent is a very important part of surgical treatment. In this paper, we report a number of legal judgements in spinal surgery where there was no criticism of the surgical procedure itself. The fault that was identified was a failure to inform the patient of alternatives to, and material risks of, surgery, or overemphasizing the benefits of surgery. In one case, there was a promise that a specific surgeon was to perform the operation, which did not ensue. All of the faults in these cases were faults purely of the consenting process. In many cases, the surgeon claimed to have explained certain risks to the patient but was unable to provide proof of doing so. We propose a checklist that, if followed, would ensure that the surgeon would take their patients through the relevant matters but also, crucially, would act as strong evidence in any future court proceedings that the appropriate discussions had taken place. Although this article focuses on spinal surgery, the principles and messages are applicable to the whole of orthopaedic surgery.

Cite this article: Bone Joint J 2019;101-B:355–360.

1. Fifty-nine patients with various inter-carpal dislocations have been reviewed. 2. In this series trans-scapho-perilunar fracture-dislocation was the commonest injury. Early cases can be reduced by closed manipulation but in late cases operative reduction is usually advisable. When the injury is more than three months old, arthrodesis of the wrist joint is indicated. 3. When trans-scapho-perilunar fracture-dislocation was complicated by avascular necrosis of the proximal scaphoid fragment, the results in a small series treated by early excision were approximately equal to those treated by continued immobilisation. The results of grafting the scaphoid were poor. 4. Dislocations of the lunate seen within ten days of injury could usually be reduced with good results; no such case developed Kienböck's disease within the period of review. In late cases excision gave satisfactory results. 5. Forward dislocation of the lunate with half the scaphoid gave good results when manual reduction succeeded, but the results of excision of fragments were less satisfactory. 6. There was one case of forward dislocation of the lunate together with the distal half of the scaphoid. 7. Subluxation of the scaphoid is disclose in antero-posterior radiographs by a typical gap between it and the lunate bone. The subluxation may become recurrent and present a characteristic syndrome. 8. Other rare dislocations of the carpal bones are described

Aims

The aim of this study was to establish the results of isolated exchange of the tibial polyethylene insert in revision total knee arthroplasty (RTKA) in patients with well-fixed femoral or tibial components. We report on a series of RTKAs where only the polyethylene was replaced, and the patients were followed for a mean of 13.2 years (10.0 to 19.1).

1. The pathological anatomy of total rupture of the ulnar collateral ligament of the metacarpo-phalangeal joint of the thumb has been studied at operation in thirty-nine patients. 2. It has been found that the ligament, when ruptured distally (the most usual type) is often displaced so that the ulnar expansion of the dorsal aponeurosis–here referred to as the adductor aponeurosis–becomes interposed between the ruptured end of the ligament and the site of its attachment on the phalanx; the ligament gets folded over to a greater or lesser extent and the ruptured end sticks out beyond the proximal edge of the adductor aponeurosis. Such displacement of the ligament with interposition of the adductor aponeurosis was found in twenty-five of the thirty-nine cases. The ligament may also be displaced without the adductor aponeurosis being interposed (with a gap between the ruptured end and the site of itsattachment on the phalanx). 3. Variations in the pathological anatomy are illustrated by more detailed descriptions of nine cases. In one of these the adductor aponeurosis had got caught between the two surfaces of the joint, and in another the adductor aponeurosis was found ruptured as well as the ulnar collateral ligament. 4. On the basis of dissection studies on forty-two fresh post-mortem specimens, a rational explanation is given of the pathological anatomy. 5. The results of the present investigation on clinical and anatomical material provide a strong argument in favour of operative treatment for total rupture of the ulnar collateral ligament of the metacarpo-phalangeal joint of the thumb. 6. Aspects of diagnosis and operative technique are discussed

Aims

The aim of the Scaphoid Magnetic Resonance Imaging in Trauma (SMaRT) trial was to evaluate the clinical and cost implications of using immediate MRI in the acute management of patients with a suspected fracture of the scaphoid with negative radiographs.

Aims

The aim of this study was to determine whether closed suction drain (CSD) use influences recovery of quadriceps strength and to examine the effects of drain use on secondary outcomes: quadriceps activation, intra-articular effusion, bioelectrical measure of swelling, range of movement (ROM), pain, and wound healing complications.

Aims

The primary aim of this study was to compare the wear properties of vitamin E-diffused, highly crosslinked polyethylene (VEPE) and one formulation of moderately crosslinked and mechanically annealed ultra-high molecular weight polyethylene (ModXLPE) in patients five years after primary total hip arthroplasty (THA). The secondary aim was to assess the clinical results of patients treated with VEPE by evaluating patient-reported outcome measures (PROMs), radiological evidence of fixation, and the incidence of mechanical failure.

Aims

There is little information about how to manage patients with a recurvatum deformity of the distal tibia and osteoarthritis (OA) of the ankle. The aim of this study was to evaluate the functional and radiological outcome of addressing this deformity using a flexion osteotomy and to assess the progression of OA after this procedure.

Aims

The purpose of this study was to evaluate the biological fixation of a 3D printed porous implant, with and without different hydroxyapatite (HA) coatings, in a canine model.