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Sir,
I was very interested by the article entitled "Synchronous perforation of a Meckel’s diverticulum and doudenal ulcer" by J.R. Saunders, M.P. Griffiths and S.S. Kadirkamanathan, published J.R.Coll.Surg.Edinb October 2001, 46: 311-312.
It is very unusual to witness a dual perforation of the gastro-intestinal tract due to separate pathology. Are the authors certain that, in this case, there is dual pathology? The authors mention that, as expected, the Meckel’s diverticulum contained ectopic gastric mucosa. Have they excluded a Zollinger Ellison syndrome? Did they measure serum gastrin levels and performed a secretine stimulation test?
From a theoretical point of view, dual perforation of the gastric and or duodenal tract should raise the suspicsion of an underlying pathology with exagerated gastric acid secretion.
However, I am unaware of a published report of such an aetiology - Meckel’s diverticulum perforation associated with a duodenal ulcer perforation. This case might be the first one.
Yours sincerely,
Professor C. Proye FRCS, FRCS Ed (Hon)
Past-President of the International Association of Endocrine
Surgeons, Clinique Chirurgicale Adultes Est, Service de
Chirurgie Generale et Endocrinene, Hopital Huriez, 1 Rue
Michel Polonowski, 5037 Lille Cedex, France
Sir,
The patient’s serum gastrin level was not elevated. Based on this it is unlikely that the diagnosis is Zollinger-Ellison syndrome. We did not go on to perform a secretin stimulation test.
Yours sincerely,
Mr J.R. Saunders
The Royal London Hospital, 4th Floor Alexandra Wing, London
E1 1BB, UK
Sir,
I wish to comment on a recent paper in the Journal of the Royal College of Surgeons of Edinburgh, 46, October 2001 265-270, “Focused rigidity casting: a prospective randomised study”.1 I feel it is seriously flawed in its study design, and yet draws conclusions that may be used to change orthopaedic practice. Many people (including the “ ‘artisan’ cast technicians” to whom the article refers) will remain unaware of the publications weaknesses, because they are not trained to assess methodology or statistics.
The ‘methods and materials’ section does not describe the randomisation method, and it is not clear at what stage this was performed (whether at initial Accident and Emergency Department attendance or subsequently in the Fracture Clinic). Hence, the sample is open to selection bias. Furthermore, it is controversial whether undisplaced 5th metatarsal avulsion fractures require immobilisation at all, or whether a ‘scaphoid cast’ confers any benefit over a ‘Colles’ cast’.2,3 The article, therefore, trials casts which may not be standard practice in many hospitals.
The methods of assessing muscle strength and range of movement are also of concern. It appears that the muscle strength assessment was entirely subjective and the opportunity to measure objectively was missed, for example with a standard grip strength dynamometer. How were the percentages of movement reduction accurately calculated if a measuring device was not used? Admittedly measuring strength of sub-talar movements is difficult, but if focused rigidity casting (FRC) prevented subtalar weakness or stiffness, this would be of interest. It would be helpful to know if the movement limitation the authors observed after cast removal was still significant at subsequent follow-up. In addition, the focused rigidity cast shown in Figure 1a extends distal to the metacarpo-phalangeal joints, and this would be expected to produce more stiffness than a standard plaster rather than a significantly better outcome.1
The need for a pilot study and statistical advice prior to a major research project is clearly demonstrated in the ‘results’ section. In a prospective study of 200 patients, 85 exclusions is high. Uncommon fractures should never have been included in the randomisation process. ‘Block randomisation’ may have been appropriate with such small numbers, and would have prevented in the ankle fracture group an 11 to 6 split between FRC and standard plaster. The ‘in cast final evaluation form’ (Figure 3) asks the date of return to work and if a physiotherapy referral was made.1 These are important questions when considering whether a change in casting practice is worthwhile, but in the ‘results’ section they are ignored completely. The use of a research assistant to analyse results, funded by the company producing the casting material, should be noted as a ‘conflict of interest’ rather than simply an acknowledgement’ unless she was working independently, in which case this should be made clear.
The ‘conclusion’ stating that this article constitutes a “rigorous scientific investigation” is invalid for the reasons above. This publication attempts to address an important topic that is hard to investigate for many practical reasons, and the background contained in the ‘introduction’ is useful. However, it is essentially a highly flawed pilot study, and we are surprised that it passed the peer review process without substantial clarification or revision.
Yours sincerely,
Mr W.N. Martin FRCSEd and Mr H. Sandhu MA, FRCS
Research Registrar and Specialist Registrar, Department of
Trauma and Orthopaedics, Royal United Hospital, Combe
Park, Bath, BA1 3NG, UK
1. Cohen AP, Shaw DL. Focused rigidity casting:
prospective randomised study. JR Coll Surg Edinb 2001, 46:
265-70
2. Clapper MF, O’Brien TJ, Lyons PM. Fractures of the
fifth metatarsal. Analysis of a fracture registry. Clin
Orthop 1995, 315: 238-41
3. Clay NR, Dias JJ, Costigan PS, Gregg PJ, Barton NJ. Need the thumb be immobilised in scaphoid fractures? A
randomised prospective trial. J Bone Joint Surg Br 1991,
73: 828-32
Sir,
We thank Mr Martin for his interest in our article, and are delighted to be afforded the opportunity to reply to the points he raises.
As Mr Martin quite correctly points out, the design of a study such as ours presents a number of practical difficulties. In addressing this issue, our intention was to conduct a study which reflected the injuries treated in a typical fracture clinic, and the methods used for both the treatment of these injuries and assessment of the final outcome. Our clearly stated intention was to compare two different casting methods used in the treatment of commonly encountered injuries. Our department, in common with many others in the authors’ experience, uses cast treatment fractures of the fifth metatarsal, and scaphoid casts for fractures of the scaphoid, and our study reflects this. It is, of course, for individual clinicians to decide if they prefer a different treatment modality to those we have analysed in our study.
Following consultation with our colleagues in the department of medical statistics, we randomised 200 consecutive attendees to our fracture clinic at their first attendance by a sealed envelope system. Consecutive patients were used precisely to eliminate the selection bias to which Mr Martin refers. It is difficult to appreciate how a system of block randomisation could result in less selection bias, although it is clear that such a system would have generated larger numbers. Although 85 exclusions were indeed high, the reasons for this were clearly stated, and inherent in a system involving consecutive patients. Further studies are ongoing examining the injuries such as the ankle fracture group, in which, because of small numbers, a type II error may have occurred during this study.
The methods used in the evaluation of muscle strength and range of motion were selected to reflect the traditional methods available in a standard fracture clinic. Although subjective, the use of clinical judgement to assess the percentage loss of muscle strength is in common use and is well established in systems such as the Medical Research Council scale for the grading of power in the assessment of myotomal deficit, and the system we selected has been validated in the literature.1,2 The use of a grip strength dynamometer, whilst inherently more accurate, is not applicable to 5th metatarsal base and ankle fractures and would, therefore, not have provided a standard method of assessment of outcome applicable to all the treatment groups. We, therefore, elected not to employ such a system in this study. We did use a goniometer to measure range of motion compared with the controlateral side as this tool, unlike a grip strength dynomometer, is readily available in most fracture clinics.
The aim of Focused Rigidity Casting is to allow an earlier return to function, rather than to influence the quality of the final outcome, which would be expected to be favourable in the population we studied.3 For this reason the patients were not followed up for a prolonged period. Earlier return of function, however, is a factor. We were unable to present the information regarding date of return to work or normal occupation because of insufficient data in connection with that part of the study. We do, however, concede that such data would have been of value. Similarly, in this population of patients, referral to the physiotherapy department was rare, and no differences could be demonstrated.
We do not agree with Mr Martin that our paramedical colleagues are less well placed to interpret the medical literature Casting technicians are highly trained personnel who are often more appraised of both the techniques and literature surrounding their craft than many orthopaedic surgeons. This precise point is currently undergoing debate regarding the place of training in casting techniques for higher surgical trainees, as witness by a recent straw poll amongst British Orthopaedic Trainee Association members which demonstrated a shortfall in this area. Indeed, this study was only possible with the cooperation in planning and execution by our colleagues in the plaster room.
No conflict of interest occurred concerning the assistance provided by the research assistant employed in this study, whose role was confined to that of provision of the statistical softwear utilised in the analysis of our results.
In summary, we disagree profoundly with Mr Martins comments that our article is ‘highly flawed’, but welcome his contribution to the debate involving the current status of casting in orthopaedic and trauma practice.
Yours sincerely,
Mr A.P. Cohen and Mr D.L. Shaw
Department of Trauma and Orthopaedics, Royal United
Hospital, Combe Park, Bath, BA1 3NG
1. Hamilton BB, Fuhrer MJ. Functional Independence Measure (FIM) In: Pynsent JB, Fairbank JCT, Carr
AJ, eds. Outcome Measures in Trauma. Butterworth
Heineman: Oxford, 1997: 210
2. Brooks RH, Callahan LF, Pincus T. Use of self-report
activities of daily living questionnaires in osteoarthritis.
Arthritis Care Res 1988, 1: 23-32
3. WeirzimokA, Houben F, Wilmen HR. Definitive primary
care of fracture. Dialog 1996, 1: 26-8