Predictors of mortality following conservatively managed fractures of the odontoid in elderly patients.

AIMS: Rates of mortality as high as 25% to 30% have been described following fractures of the odontoid in the elderly population. The aim of this study was to examine whether easily identifiable variables present on admission are associated with mortality. PATIENTS AND METHODS: A consecutive series of 83 elderly patients with a fracture of the odontoid following a low-impact injury was identified retrospectively. Data that were collected included demographics, past medical history and the results of blood tests on admission. Radiological investigations were used to assess the Anderson and D'Alonzo classification and displacement of the fracture. The mean age was 82.9 years (65 to 101). Most patients (66; 79.5%) had a type 2 fracture. An associated neurological deficit was present in 11 (13.3%). All were treated conservatively; 80 (96.4%) with a hard collar and three (3.6%) with halo vest immobilisation. RESULTS: The rate of mortality was 16% (13 patients) at 30 days and 24% (20 patients) at one year after injury. A low serum level of haemoglobin and the presence of a neurological deficit on admission were independent predicators of mortality at 30 days on binary logistic regression analysis. A, low level of haemoglobin, admission from an institution, a neurological deficit and type 3 fractures were independent predictors of mortality at one year. CONCLUSION: We suggest that these easily identifiable predictors present on admission can be used to identify patients at high risk and guide management by a multidisciplinary team. Cite this article: Bone Joint J 2017;99-B:116-21.

Functional relevance of patellofemoral thickness before and after unicompartmental patellofemoral replacement.

The aim of this study was to assess the increase in the anterior height of the knee after unicompartmental patellofemoral replacement and the impact of this increase on the range of motion and function of the knee. Twenty-eight patients (34 knees) who underwent patellofemoral replacement with FPV(TM) prosthesis between 2005 and 2009 were identified and retrospectively analyzed using chart and radiological review. Trochlear height and patellar thickness were measured combined and compared pre and postoperatively. The range of movement and functional outcome scores after 6-12 months follow-up were noted. The effect of increased postoperative anterior-posterior height of the knee on the range of motion was studied. Postoperative mean range of flexion of the knee joint was 116°. The mean Oxford knee score was 21 points. The mean American Knee Society Knee Score was 80 points for pain and 61 points for function. The trochlear height and patellar thickness were increased by 3.5 and 2.5 mms respectively, resulting in average total increase of 6mm in the anterior-posterior height of the knee. We found no relationship between range of motion and function of the knee and the increase in the anterior-posterior height. We found a negative correlation between increase in the anterior-posterior height and preoperative anterior-posterior height. FPV patellofemoral replacement results in correct anatomical reconstruction of the trochlear height rather than 'overstuffing' of the patellofemoral joint. There is an increase in anterior-posterior height of the knee but this does not affect range of movement or clinical outcome.

Successful treatment of refractory tibial nonunion using calcium sulphate and bone marrow stromal cell implantation.

Successful healing of a nine-year tibial nonunion resistant to six previous surgical procedures was achieved by tissue engineering. We used autologous bone marrow stromal cells (BMSCs) expanded to 5 x 10(6) cells after three weeks' tissue culture. Calcium sulphate (CaSO4) in pellet form was combined with these cells at operation. The nonunion was clinically and radiologically healed two months after implantation. This is the description of on healing of a long-standing tibial nonunion by tissue engineering. The successful combination of BMSCs and CaSO4 has not to our knowledge been reported in a clinical setting.

Peripheral sympathetic conduction velocity calculated from surface potentials.

A simple, non-invasive and well tolerated technique is described for measuring autonomic nerve conduction velocity (ANCV) using proximal and distal peripheral autonomic surface potential (PASP) recordings. ANCV were obtained in 90% of subjects, and are comparable to values measured by intraneural recording. This technique may have applications in the assessment of autonomic neuropathies and can be readily performed in a standard EMG laboratory.

Peripheral autonomic surface potential. A quantitative technique for recording sympathetic conduction in man.

Using EMG equipment with time locked recording and standard averaging facilities we were able to record a previously poorly defined skin potential. The potential, termed by us the peripheral autonomic surface potential (PASP), was recorded from the palmar surface of the hand and the plantar surface of the foot in 30 normal subjects. The PASP usually consisted of a biphasic potential with an initial negative and a later positive peak. It was elicited by randomly timed electrical stimuli over the median nerve at the wrist. The mean palmar PASP latency was 1.52 +/- 0.13 s and the mean plantar PASP latency was 2.07 +/- 0.16 s. The mean palmar and plantar PASP amplitudes were 479 +/- 105 microV and 101 +/- 40 microV, respectively. A mean sympathetic conduction velocity was calculated to be 1.28 +/- 0.18 m/s. In 5 normal subjects a similar technique was used to record a PASP from the volar surface of the left middle finger. Iontophoresis of atropine into the skin under the recording site abolished the PASP in all subjects. Palmar and plantar PASPs were recorded in 10 diabetic patients. The amplitudes (palmar 179 +/- 158 microV, plantar 17 +/- 16 microV) were significantly reduced compared to normals (P less than 0.001). Five patients with unilateral lumbar or cervical sympathectomy were studied. The PASP was absent or markedly reduced on the side of the sympathectomy in all patients.

Peripheral autonomic surface potential: a quantitative technique for recording autonomic neural function in man.

Using EMG equipment with time-locked recording and standard averaging facilities we were able to record a previously poorly studied skin potential. The potential, termed by us by the peripheral autonomic surface potential (PASP), was recorded from the palmar surface of the hand and the plantar surface of the foot in 20 normal subjects. The PASP consisted of a biphasic potential with an initial negative and a later positive peak. The mean palmar PASP latency was 1.51 +/- 0.19 seconds and the mean plantar PASP latency was 2.09 +/- 0.24 seconds. The mean palmar and plantar PASP amplitudes were 485 +/- 100 microV and 102 +/- 45 microV respectively. A mean central sympathetic conduction velocity was calculated at 1.2 +/- 0.21 m/s. In two patients with unilateral lumbar sympathectomy the ipsilateral plantar PASP was absent in one and of considerably reduced amplitude in the other. Both palmar and plantar PASPs were absent or of reduced amplitude in five patients with diabetes mellitus. The study indicates that the PASP may prove a useful quantitative test of central and peripheral autonomic function.

Nerve conduction velocity in experimental diabetes in the rat and rabbit.

Tibial motor nerve conduction velocity was measured in rats, before and two months after the induction of diabetes with streptozotocin. A second group of diabetic animals was also administered 1% dietary myoinositol supplements. An analysis of variance was performed on these data. Myoinositol supplements had no effect whatsoever. The period of diabetes had a statistically significant and quantitatively marginal effect (a decrease of 2.2 m s-1) on conduction velocity. This is considerably less than in previous reports. The reasons for this are discussed. Tibial motor nerve conduction velocity was also measured in a group of alloxan-diabetic rabbits two months after the induction of diabetes and in an age-matched control group. Conduction velocity was again slightly but significantly less in the diabetic animals.

Transcutaneous sympathetic stimulation: effects of autonomic nervous function.

In recent years the use of transcutaneous electrical nerve stimulation (TENS) for the treatment of painful disorders has been widely adopted. Minor side effects such as skin irritation are recognised but with appropriate safeguards the technique is considered free from permanent sequelae. This study examines the effects of TENS on hand skin temperature in 6 normal volunteers and 3 patients with alcoholic peripheral neuropathy. Changes of skin temperature were registered using thermocouples and a thermovision camera. Digital artery pulsation was recorded using the Doppler ultrasound technique. Stimulation at 5 to 10 per second of the ulnar nerve at the elbow and digital nerves in the fingers was maintained for 1 to 4 minutes. Profound cooling of the skin and decrease in arterial pulsation was observed and usually persisted for several minutes after cessation of stimulation. Digital arterial changes were not seen in the 3 patients with neuropathy. The possible physiological basis of the observations is discussed and the implications for TENS therapy considered.

Effects of induced hyperthermia on visual evoked potentials and saccade parameters in normal subjects and multiple sclerosis patients.

A convenient method for raising body temperature has been developed and used to evaluate temperature effects on visual evoked potentials and saccade reaction time and velocity in five normal subjects and five patients with multiple sclerosis.

[Automatic analysis of the electromyogram: technique and results in healthy and ill subjects]. / Analyse automatique de l'électromyogramme: technique et résultats chez des sujets sains et des malades.

The EMG signal was recorded from the brachial biceps in 12 different needle positions, in control subjects and patients, all the subjects exerting a standard effort. The signal was automatically analysed, off-line, and 18 parameters were computed from the signal waves. These parameters described the electrical activity of the muscle. The comparison between results from control subjects and patients showed significant differences for 13 parameters. Eight of them allowed one to separate neurogenic and myogenic patients. For each parameter, the observed variations from the normal exhibited opposite values for neurogenic and myogenic subjects. Some neurogenic patients with apparently normal biceps had a pathological quantitative analysis. The method could thus be used to reveal early disturbances.

Axoplasmic transport in vagal afferent fibres in normal and alloxan-diabetic rabbits.

Fast and slow components of anterograde axoplasmic transport have been studied in the sensory fibres of the vagus nerve of alloxan-diabetic rabbits and age-matched controls by incorporation of tritiated leucine into nodose ganglion cells. The diabetic rabbits were maintained for 2 months with blood glucose levels in the range 20--40 mmol/l. They showed growth retardation and one third developed cataracts. No alteration of either fast or slow axoplasmic transport was detected in the diabetic animals. These results are discussed in the light of the present understanding of the role of axoplasmic transport, of the findings in other axoplasmic transport studies, and of other data available on the pathogenesis of human and experimental diabetic neuropathy.

Amyloid neuropathy and tremor in Waldenström's macroglobulinemia.

We report a case of Waldenström's macroglobulinemia with amyloid neuropathy and a parkinsonian syndrome. We describe the light and electron microscopic findings in a sural nerve biopsy specimen and discuss the possible pathogenic mechanisms in the production of the neuropathy. In contrast to a number of previous cases of neuropathy associated with Waldenström's macroglobulinemia, evidence of immunoglobulin deposition on nerve fibers was not found using immunofluorescent techniques.

Age changes in the tibial and plantar nerves of the rat.

Observations have been made on the changes in the myelinated fibres of the rat tibial and plantar nerves between 2 and 24 months of age. There is an initial rapid increase in fibre diameter followed by a later more gradual increase, which ceases after approximately 9 months of age in the tibial nerve but which continues for longer in the medial plantar nerve. The fibre size distribution remains substantially unimodal throughout. In both nerves maximal and average fibre diameter become reduced by 24 months. Total fibre number shows considerable variability between animals, but no definite systematic alteration with age is detectable. Teased fibre preparations demonstrate a low level of abnormality in the tibial nerve until after 18 months of age, but by 24 months approximately 30% of fibres display abnormalities. Although both paranodal and segmental demyelination and remyelination, and axonal degeneration and regeneration occur, the latter type of change predominates. By contrast, in the lateral plantar nerve paranodal and segmental demyelination become detectable to a significant extent from 6 months of age. Axonal degeneration and regeneration also become evident after 15 months, and by 24 months of age 55% of fibres show abnormalities. The possible explanation of these changes is discussed, as is their relevance to the frequent use of the tibial nerve for studies on experimental neuropathies.

Dihydroergotamine therapy in symptomatic postural hypotension.

The clinical response to therapy with dihydroergotamine (DHE) has been evaluated in one patient with idiopathic orthostatic hypotension. The results of tests performed on the autonomic nervous system are recorded, and the evidence for a central defect in postural blood pressure control is presented. Tilt table testing over a two-month period confirmed the beneficial effect of the medication in preventing profound falls of blood pressure. The dose required (20 mg/day) was higher than previously reported.