Joseph Swan (1791-1874): pioneer of research on peripheral nerves.

Joseph Swan was born in 1791 and appointed surgeon to Lincoln County Hospital in 1814. In addition to his clinical work, he carried out what were probably the first animal experiments on nerve injuries. These were mostly on rabbits, in which the sciatic nerves were partly or wholly divided, had a section excised, or were ligated. He found that regeneration could occur, even after neurectomy. He reported these results, together with his experience in human patients and the effects of neurectomy in a horse, in an essay of 1819, which won the Jacksonian Prize of the Royal College of Surgeons of England and is still preserved there. In 1827 he moved to London, where he devoted himself mainly to dissections of the nervous system and was active in the College. He retired to Filey in Yorkshire, where he died in 1874.

Bilateral vagotomy or atropine pre-treatment reduces experimental diesel-soot induced lung inflammation.

To investigate the role of the vagus nerve in acute inflammatory and cardiorespiratory responses to diesel particulate (DP) in the rat airway, we measured changes in respiration, blood pressure and neutrophils in lungs of urethane anesthetized Wistar rats 6-h post-instillation of DP (500 microg) and studied the effect of mid-cervical vagotomy or atropine (1 mg kg(-1)) pre-treatment. In conscious rats, we investigated DP, with and without atropine pre-treatment. DP increased neutrophil level in BAL (bronchoalveolar lavage) fluid from intact anesthetized rats to 2.5+/-0.7x10(6) cells (n=8), compared with saline instillation (0.3+/-0.1x10(6), n=7; P<0.05). Vagotomy reduced DP neutrophilia to 0.8+/-0.2x10(6) cells (n=8; P<0.05 vs. intact); atropine reduced DP-induced neutrophilia to 0.3+/-0.2x10(6) (n=4; P<0.05). In conscious rats, DP neutrophilia of 8.5+/-1.8x10(6), n=4, was reduced by pre-treatment with atropine to 2.2+/-1.2x10(6) cells, n=3. Hyperventilation occurred 6 h after DP in anesthetized rats with intact vagi, but not in bilaterally vagotomized or atropine pre-treated animals and was abolished by vagotomy (P<0.05, paired test). There were no significant differences in the other variables (mean blood pressure, heart rate and heart rate variability) measured before and 360 min after DP. In conclusion, DP activates a pro-inflammatory vago-vagal reflex which is reduced by atropine. Muscarinic ACh receptors in the rat lung are involved in DP-induced neutrophilia, and hence muscarinic antagonists may reduce airway and/or cardiovascular inflammation evoked by inhaled atmospheric DP in susceptible individuals.

Attenuation of experimental arthritis in TRPV1R knockout mice.

The Transient Receptor Potential Vanilloid 1 (TRPV1R) is a ligand-gated, non-selective cation channel expressed predominantly by sensory neurons. TRPV1Rs respond to a variety of noxious stimuli including capsaicin, intense heat and acid. These factors, combined with behavioral studies, show that TRPV1Rs are involved in nociception. The aim of our study was to determine whether TRPV1Rs play a role in the development and maintenance of inflammation and mechanical hyperalgesia by studying the development of unilateral joint inflammation in TRPV1R-/- mice. Knee joints of TRPV1R-/- or wild-type (WT) mice were injected with FCA (200 microg) under temporary anesthesia, and the resulting inflammation and hyperalgesia measured for 35 days. Histological analysis was performed on joints at the end of the study. TRPV1R-/- mice developed mild joint swelling which was significantly less than that obtained in WT mice (P < 0.05, Mann-Whitney). The ratio of the weight distribution between the hind limbs in TRPV1R-/- mice was also significantly less than in WT mice (P < 0.05, Mann-Whitney). Neither swelling nor hypersensitivity was completely absent in the knockout mice, indicating either that other mechanisms are involved or that a compensatory mechanism operates in TRPV1R-/- mice. These results suggest that TRPV1 receptors are important for the development of joint inflammation and the associated mechanical hypersensitivity observed in this model.

Incidence of osteoarthritis in the scapho-trapezial joint after Herbert screw fixation of the scaphoid.

Twenty patients treated with a Herbert screw for scaphoid fractures (acute or non-union) were reviewed and X-rayed 5-10 years later to assess whether there were degenerative changes in the scapho-trapezial joint due to insertion of the screw. Six had some irregularity in the lateral part of that joint, three of which followed backing-out of the screw. Two others were described as showing irregularity all round the scaphoid but, apart from these, no radiological abnormalities were seen in the central or ulnar part of the scapho-trapezial joint, or on the proximal tip of the scaphoid.

The treatment of dorsal fracture-dislocation of the proximal interphalangeal joint by closed reduction and Kirschner wire fixation: a 16-year follow up.

Ten patients who had sustained 11 unstable dorsal fracture-dislocations of finger proximal interphalangeal joints were reviewed at a mean follow-up of 16 years. All had been treated acutely by closed reduction and transarticular Kirschner wire fixation of the proximal interphalangeal joint, without any attempt at reduction of the fracture of the base of the middle phalanx, which probably involved 30-60% of the articular surface. Seven of the ten patients complained of no finger pain or stiffness, and none complained of severe pain. There was a mean fixed flexion deformity of 8 degrees at the proximal interphalangeal joint, which had a mean arc of movement of 85 degrees. Although subchondral sclerosis and mild joint space narrowing were observed in some instances, there were no severe degenerative changes. These results confirm that this technique is a reliable treatment method for these injuries, and produces satisfactory long-term results.

Factors influencing the outcome of bone grafting surgery for scaphoid fracture non-union.

The results of a consecutive series of bone-grafting procedures for non-union of scaphoid fractures were assessed in order to investigate whether the patient's age or the delay between acute fracture and bone-graft surgery influenced the outcome. One hundred and thirty-four patients with a mean follow up of 2.6 years from bone-graft surgery for scaphoid fracture non-union were assessed for post-operative pain and radiographic evidence of union. No association was found between the union rate following surgery and either the patients' ages or the interval between the original injury and subsequent non-union surgery.

The prognostic value and reproducibility of the radiological features of the fractured scaphoid.

We investigated whether the radiological features of the fractured scaphoid could be reproducibly measured and used to predict the likelihood of union with conservative plaster cast immobilization. We found that the inter- and intra-observer reproducibility of the Compson, Herbert and Russe classification systems were only fair and that none predicted fracture union. Assessments of fracture level, comminution and displacement showed moderate inter- and intra-observer reproducibility but did not predict the likelihood of fracture union. We conclude that the radiological features of acute scaphoid fractures cannot be used to predict the likelihood of fracture union.

Acute fractures of the scaphoid. Treatment by cast immobilisation with the wrist in flexion or extension?

Acute fractures of the scaphoid were randomly allocated for conservative treatment in a Colles'-type plaster cast with the wrist immobilised in either 20 degrees flexion or 20 degrees extension. The position of the wrist did not influence the rate of union of the fracture (89%) but when reviewed after six months the wrists which had been immobilised in flexion had a greater restriction of extension. We recommend that acute fractures of the scaphoid should be treated in a Colles'-type cast with the wrist in slight extension.

Experience with scaphoid grafting.

Over a period of 24 years, the author has used five different methods of bone-grafting for ununited scaphoid fractures. The clinical and radiological results have been reviewed, with a minimum follow-up of 1 year. Radiologically the best results (78% definite union) were obtained with a "wedge" graft and Herbert screw, while the worst results followed the original Russe operation. The clinical result often did not coincide with the radiological outcome. All methods led to a decrease in pain in most cases, but little or no pain was achieved most often by the modified Russe graft. With proximal pole fractures, bony union was only achieved in 54% but the symptoms were always lessened.

Trapeziectomy alone, with tendon interposition or with ligament reconstruction?

This randomized prospective study compared the results of trapeziectomy alone, or combined with tendon interposition or ligament reconstruction in 76 women with basal thumb osteoarthritis. At 3 month and 1 year follow-up the results of the three procedures were indistinguishable in terms of pain relief, hand function and thumb strength. In the short term at least, tendon interposition and ligament reconstruction do not improve the results of trapeziectomy.

Medial epicondylectomy or ulnar-nerve transposition for ulnar neuropathy at the elbow?

We carried out a prospective randomised study comparing medial epicondylectomy with anterior transposition for the treatment of ulnar neuropathy at the elbow. The mean follow-up period was 4.5 years and we assessed the patients neurologically and orthopaedically. Neither procedure appeared to have a significant effect on elbow function. Our study showed better results after medial epicondylectomy; in particular patient satisfaction was higher than after ulnar nerve transposition. There were no significant differences in motor power or nerve-conduction rates and sensory fibres appeared to be more vulnerable to devascularisation.

Apparent and partial non-union of the scaphoid.

Ten patients with radiological non-union of the scaphoid and four patients with suspected non-union were explored surgically. At operation, ten scaphoids looked united; five of these went on to definite union but the other five to non-union (in one case, despite a Herbert screw). In another four patients, there appeared at operation to be partial union; all proceeded to complete union. Even with the scaphoid in front of you, it can be difficult to decide whether it has united or not.

Outcomes of hand surgery. British Society for Surgery of the Hand.

The findings are presented of a conference on Outcomes of Hand Surgery organized by the audit committee of British Society for Surgery of the Hand in 1993. Measures of outcome in terms of movement, power, sensibility, pain, activities of daily living, complications and patient satisfaction are considered, and an example of a patient evaluation measure given as an appendix.

The therapeutic efficacy and prophylactic activity of doramectin against Dictyocaulus viviparus in cattle.

Three groups of 8, 4-month-old male Jersey or Jersey-cross calves were infected with 2400 Dictyocaulus viviparus L3 larvae and either left untreated or injected subcutaneously with 200 micrograms/kg doramectin 5 or 25 days after infection (DAI). Lungworms were found in all untreated cattle (geometric mean = 49) at necropsy 39 or 40 DAI. None was found in any of the treated cattle. In a second experiment, groups of 6, 8-month-old calves were untreated or injected with 200 micrograms/kg doramectin 28, 21 or 14 days before each calf was challenged with 2700 D viviparus larvae. Lungworms were recovered at necropsy 32 to 34 DAI. The geometric mean worm burden in the untreated cattle was 550. This was reduced by 100%, 99.5% and 94.1% in calves treated with doramectin 14, 21 or 28 days, respectively, before infection. It was concluded that doramectin is a highly effective anthelmintic against D viviparus adult or L4 infections of cattle, and that reinfection of treated cattle will be significantly reduced for at least 28 days after treatment.

Clinical signs in scaphoid fractures.

In a prospective study we investigated 12 clinical features for scaphoid fractures in 52 patients: 23 in whom a fracture of the scaphoid was diagnosed radiologically and 29 patients in whom a fracture was clinically suspected but could not be confirmed by radiography or scintigraphy. The signs were tested within a few days of injury and again 2 weeks later. None was reliable in diagnosing a scaphoid fracture.