Total hip arthroplasty versus resurfacing arthroplasty in the treatment of patients with arthritis of the hip joint: single centre, parallel group, assessor blinded, randomised controlled trial.

OBJECTIVES: To compare the clinical and cost effectiveness of total hip arthroplasty with resurfacing arthroplasty in patients with severe arthritis of the hip. DESIGN: Single centre, two arm, parallel group, assessor blinded, randomised controlled trial with 1:1 treatment allocation. SETTING: One large teaching hospital in the United Kingdom. PARTICIPANTS: 126 patients older than 18 years with severe arthritis of the hip joint, suitable for resurfacing arthroplasty of the hip. Patients were excluded if they were considered to be unable to adhere to trial procedures or complete questionnaires. INTERVENTIONS: Total hip arthroplasty (replacement of entire femoral head and neck); hip resurfacing arthroplasty (replacement of the articular surface of femoral head only, femoral neck remains intact). Both procedures replaced the articular surface of the acetabulum. MAIN OUTCOME MEASURES: Hip function at 12 months after surgery, assessed using the Oxford hip score and Harris hip score. Secondary outcomes were quality of life, disability rating, physical activity level, complications, and cost effectiveness. RESULTS: 60 patients were randomly assigned to hip resurfacing arthroplasty and 66 to total hip arthroplasty. Intention to treat analysis showed no evidence for a difference in hip function between treatment groups at 12 months (t test, P=0.242 and P=0.070 for Oxford hip score and Harris hip score, respectively); 95% of follow-up data was available for analysis. Mean Oxford hip score was 40.4 (95% confidence interval 37.9 to 42.9) in the resurfacing group and 38.2 (35.3 to 41.0) in the total arthroplasty group (estimated treatment effect size 2.23 (-1.52 to 5.98)). Mean Harris hip score was 88.4 (84.4 to 92.4) in the resurfacing group and 82.3 (77.2 to 87.5) in the total arthroplasty group (6.04 (-0.51 to 12.58)). Although we saw no evidence of a difference, we cannot definitively exclude clinically meaningful differences in hip function in the short term. Overall complication rates did not differ between treatment groups (P=0.291). However, we saw more wound complications in the total arthroplasty group (P=0.056) and more thromboembolic events in the resurfacing group (P=0.049). CONCLUSIONS: No evidence of a difference in hip function was seen in patients with severe arthritis of the hip, one year after receiving a total hip arthroplasty versus resurfacing arthroplasty. The long term effects of these interventions remain uncertain. TRIAL REGISTRATION: Current Controlled Trials ISRCTN33354155, UKCRN 4093.

Femoral neck narrowing following hip resurfacing using posterior and Ganz approaches at two years.

We report a retrospective review of femoral head/neck ratios on post-operative and two year follow-up radiographs following hip resurfacing arthroplasty. The patients were in two matched groups, having had surgery through a posterior approach or via a Ganz trochanteric flip. There was no significant difference in femoral neck narrowing at follow up between the two surgical approaches. However, we found significant narrowing of the femoral neck in both groups by the time of the two year follow-up radiograph.

"Electromyographic pattern of masticatory muscles in altered dentition" Part II.

AIM: The aim of this study is to show that a change in occlusal contacting pattern of tooth has definite influence over the behavior of orofacial musculature, resulting deleterious effect on it. Keeping this in view, the electromyographic (EMG) activity of temporalis and masseter muscles in rest position of mandible, maximum clenching and chewing, was studied in total 24 subjects--14 subjects with normal occlusion and rest 10 with normal occlusion and one tooth carious which was prepared to receive an inlay with high point. This high point or occlusal interference was introduced intentionally to have a change in occlusion or "altered dentition". The subjects were all male medical volunteers with average age group of 20 years. A particular variety of chewing substance - chewing gum was used in this study. No EMG activity was detected in the rest position of mandible. In maximum clenching, balanced type of activity was seen bilaterally in normal occlusion. Whereas in changed occlusion, an unbalanced type of muscle activity was seen in temporalis muscle during maximum clenching. There was an overall decrease in activity in both the muscles during maximum clenching and during chewing. This decrease in activity was statistically significant in most of the times. A non-specific pattern of muscle activity resembling spasm in skeletal muscle -- a state of "hyperactivity" was also found during chewing in presence of occlusal interference. This spasm-like activity may cause pain in the muscles of masticatory apparatus. All these abnormal types of behavior of muscle were abolished after removal of high point and establishing the previous normal occlusion. It is therefore, for the clinicians to understand the importance of establishing occlusal equilibrium in day to day practice.

Metal-on-metal hip resurfacing with uncemented fixation of the femoral component. A minimum 2 year follow up.

The current generation of metal-on-metal hip resurfacing designs has largely been characterized by cemented femoral fixation using a cementless cup. We present the clinical results of 135 entirely uncemented metal-on-metal hip resurfacing procedures. The primary outcome measures were revision for any cause and the Oxford hip score at the latest follow up. The average length of followup was 2.9 years. The mean Oxford hip score was 18.4 and no patient required revision of either component during the study period. Uncemented femoral fixation may be comparable to fixation with cement in metal-on-metal hip resurfacing.

Effect of prematurity and intrauterine growth restriction on H-reflex recovery cycle in neonates.

OBJECTIVE: The purpose of this work was to assess the effects of prematurity and intrauterine growth restriction on spinal cord synapses using H-reflex. METHODS: 33 babies were investigated at birth. 14 were full term appropriate for gestational age (FT AGA), 10 were full term intrauterine growth restricted (FT IUGR) and 9 were preterm appropriate for gestational age (PT AGA). The maximum amplitude of H-reflex (Hmax), H-reflex latency (HRL), H/M ratio, H-reflex conduction velocity (HRCV), and H-reflex response to double stimuli (conditioning and test) for H-reflex recovery cycle (HRRC) were recorded in right lower limb (soleus muscle) in all the three groups. RESULTS: Percentage recovery values of H-reflex were significantly higher in FT AGA and FT IUGR babies compared to PT AGA neonates for most of inter-stimulus intervals. No significant differences were observed in H-reflex parameters between FT AGA and FT IUGR groups, but HRL and HRCV were significantly affected in PT AGA group. CONCLUSIONS: Delayed H-reflex recovery in preterms may be due to a prolonged state of neurotransmitter delay in Ia terminals following initial activation by the conditioning stimuli. The cause of such prolonged depletion of neurotransmitters could be attributed to a poor neurotransmitter store in synaptic vesicles of spinal cord in preterm neonates.

Intertrochanteric femoral fracture after hip resurfacing managed with a reverse distal femoral locking plate: a case report.

Metal-on-metal hip resurfacing is a popular procedure for a select group of patients. A variety of surgical approaches are being utilised, each of which may be associated with specific complications. We describe an unusual complication following a Ganz trochanteric osteotomy approach, and the technique used to treat the subsequent periprosthetic fracture.

Hip resurfacing using the trochanteric flip osteotomy.

We report the early results and complications of resurfacing arthroplasty using the 'Trochanteric Flip Osteotomy' approach to the hip. There are no published clinical results of this approach used for resurfacing arthroplasty. One hundred consecutive patients were assessed prospectively for a minimum follow-up of 2 years (range 2-5 years). The Oxford Hip Score fell from a median of 30 pre-operatively to 5 at two years. Similar improvement was found in the UCLA Activity Score. There were no cases of component failure or fractures. However, nine patients had minor complications related to the osteotomy. Resurfacing Arthroplasty of the hip may be successfully performed through a trochanteric flip osteotomy. This surgical approach may avoid some of the complications associated with avascular necrosis of the femoral head.

H-reflex and motor nerve conduction studies in growth retarded newborn babies.

OBJECTIVE: To demonstrate the accelerated postnatal maturation/myelination in growth retarded babies compensating the deficit suffered by them during intrauterine life. METHODS: We studied 16 babies within the first 3 days of birth. These included 6 full term appropriate for gestational age babies (FT AGA) and 10 full term intrauterine growth retarded (FT IUGR). A separate group of 16 babies was examined at 2 months of age. In this group 7 were FT AGA and 9 were FT IUGR at the time of birth. H-reflex latency (HRL), motor nerve conduction velocity (MNCV) and H-reflex excitability (H/M) were measured in the right lower limb. Anthropometric measurements of the babies were also recorded meticulously. All the babies were neurologically normal on clinical evaluation. RESULT: At birth, MNCV was significantly lower in FT IUGR babies compared to FT AGA babies. However at the age of 2 months the MNCV of both FT AGA and FT IUGR was comparable. Other parameters (HRL and H/M) in the IUGR babies were comparable with normal babies both at birth and 2 months of age. In FT IUGR babies crown-heel length and weight was significantly lower than FT AGA babies both at the time of birth and at 2 months of age. CONCLUSION AND SIGNIFICANCE: The findings suggest that FT IUGR babies demonstrate accelerated postnatal peripheral neural maturation. At 2 months of age, the motor nerve conduction velocity of these growth retarded babies was comparable to that observed in normal AGA babies of similar age. This provides an insight into the functional aspect of the proven theories of decreased peripheral myelination in FT IUGR babies with subsequent rapid postnatal myelination that renders these babies neurologically equivalent to FT AGA babies despite not achieving comparable anthropometric parameters.

Spinal motor neuron excitability in newborns following fetal distress: sub-clinical depression revealed by soleus H-reflex.

OBJECTIVE: To explore possible spinal cord dysfunction in clinically unaffected newborns emerging from fetal distress, using H-Reflex. METHODS: This cross-sectional study comprised 48 full-term newborn infants investigated between 8h and 10 days after birth. Twenty-one (21) had fetal distress defined by late-decelerations in fetal heart rate, out of which 11 had also meconium release in utero; 5 passed meconium in utero with normal FHR patterns; and 22 normal controls had uneventful birth. All had normal birth-weight and Apgar scores. All were found normal on neurological examination, except one showing hypotonia following fetal distress. Soleus H-reflex was studied in right lower limb. RESULTS: Newborns delivered with fetal distress showed significant reduction in H-reflex excitability (H/M ratio) within 2 days of birth. Tests performed closer to the birth event revealed more severe depression. Meconium did not contribute to this effect. CONCLUSIONS: Fetal distress can lead to transient, subclinical depression of spinal motoneurons in the newborn. SIGNIFICANCE: This neonatal H-reflex study focuses on excitability of a spinal motoneuron pool rather than conduction parameters (reflecting myelination) available in literature. It reveals excitability changes missed on clinical examination of newborns apparently unaffected by intrapartum hypoxic-ischemic spells. It also draws attention towards spinal cord dysfunction in birth-hypoxia.

Hemiarthroplasty for severe fractures of the proximal humerus.

Twenty-two patients were followed up at a mean of 33 months after hemiarthroplasty for proximal humeral fractures. Of these, 13 underwent surgery within 30 days of injury and 9 after a mean of 13 months. Outcome was assessed by pain, range of motion, function, stability, and strength. Results were comparable to those from specialist centers. Pain relief was the most predictable outcome. Mean active forward flexion was 93 degrees, active external rotation 24 degrees, and internal rotation to L1. Most patients were satisfied with the outcome. The results were better in younger patients. One patient required a revision after 7 years for aseptic loosening. The severity of the fracture and timing of the operation did not appear to have a bearing on the outcome. Technical problems at surgery, greater tuberosity displacement, late rotator cuff rupture, and poorly motivated patients were the main reasons for failure.