War Surgery and Medicine
CHAPTER 21 — Hernia
HERNIA is a common condition, and it is inevitable that men develop hernia during service.
In 1 NZEF operation for repair of hernia was carried out in the base hospitals overseas, and cases deemed unsuitable for operation were graded for base duty or sent back to New Zealand. The large majority of cases dealt with overseas carried on their service satisfactorily.
Second World War
The original code of instructions for medical boards laid down the following regarding the acceptance of recruits:
Hernia (Inguinal): No case however slight, should be accepted for Grade I, even if well retained by a truss; if bilateral and not large and controlled by a truss, the man may be put in Grade II. If the hernia, either single or double, is large with patulous rings, but is retained by a truss, the man must be placed in a grade below the first, the precise grade being determined by a consideration of his general physical condition. If the hernia is irreducible, the man must be placed in Grade IV. Four months is the minimum interval after operation before a man may be placed in Grade I.
Hernia was the fifth most common disability (5 per cent) in all men graded II, III, or IV at their initial medical examinations in 1942 and 1943, when older men were in the majority among those examined. Of those called up for service, 1·62 per cent could not be placed in Grade I because of hernia.
When remedial treatment for minor surgical conditions was arranged in September 1940, hernia was definitely excluded from the list of conditions for which operation was authorised. Remedial treatment could only be given to cases which could be rendered fit for training in one month. The period of four months had been laid down as the minimum between operation for hernia and full duty. Suggestions were made by regional deputies that the period of one month be extended and that treatment for hernia should be included in the list, but the DGMS firmly adhered to his opinion that men with hernia should not be given remedial treatment to fit them for service.
In June 1943 all the Regional Deputies were asked their opinion with regard to the fitness of men with hernia for duty in camp or in page 407 the Home Guard. Nearly all the replies were to the effect that men who carried out their civil occupations without any trouble, particularly if this entailed physical work, were fit for duty both in camp and in the Home Guard. It was only the sedentary workers with particularly large hernias who would be unsuitable for these duties. It was pointed out that the number of otherwise fit and healthy men with hernia was surprisingly great, and many of them did strenuous labouring work without complaint.
The necessity for regulating the physical work required in the Home Guard was stressed, and it was pointed out that many men not fit for any strenuous physical work would be employed on lighter duties and they could be so graded by the Regional Deputies. The army authorities, however, for some inexplicable reason, had instructed that no differentiation was allowable.
It would seem that the ideal solution would have been to have given the Regional Deputies the power to determine whether these men were fit for duty in camp and in the Home Guard, and in certain cases sedentary work could have been stipulated. The Pulheems system, properly applied, would readily solve all difficulties.
Hernia is a common disability, and if all men, otherwise young and fit, are automatically excluded from the army, except as graded men, it means a definite limitation of manpower for the army. The three months' treatment needed to make a hernia case fit for active service would seem to be justified in a prolonged war, provided the operation is restricted to cases likely to be Grade I and not likely to recur. There would seem to be no justification for operation on men in the older age groups or on those with feeble abdominal musculature.
Wearing of Trusses
The Regional Deputies in 1943 pointed out that very few men with hernia wore trusses, no matter what their occupation, and in spite of this they seemed to have no disability. This finding has been confirmed by Dr D. Macdonald Wilson, supervisor of medical treatments, War Pensions Department. In a survey of the 562 cases coming before War Pensions Boards up to 1952, he found that there were 232 men with unrelieved hernia, but only 18 of them stated that they wore a truss. The Department was prepared to supply trusses, but the only requests came from First World War pensioners who had worn them for twenty to thirty years, dating back to the time when doctors regularly recommended a truss if operation was not undertaken.
Overseas Experience of 2 NZEF
Some 700 men developed hernia during service overseas with 2 NZEF. The great majority were young men in whom operative repair was eminently suitable, and comparatively few were of an age at which permanent success could not be hoped for. However, all cases in the older group were carefully evaluated with regard to the prospects of future satisfactory military service. They were graded for base duties, or sent back to New Zealand without operation, if full operative success was not expected.
The practice of discouraging operation for the older group of men (those in their late thirties and forties) proved satisfactory. It was felt that these men could carry on at the Base if suited for light employment, and, if not, it was better policy for them to be employed in New Zealand.
Even if operation were successful in these cases they were unsuited for front-line duty, and the period of six months on light duty following operation was not warranted for a man fit to be employed only in Base Camp. The younger men, on the other hand, could in three months be made fit for front-line service with a very slight liability to recurrence, so operation was well justified.
In December 1943 recommendations were made by the Consultant Surgeon 2 NZEF that ‘cases with definite herniation should be referred to hospital for operation. Cases with weakness of abdominal musculature, producing some indefinite bulging of the inguinal region, should carry on. After operation care should be taken to prevent undue strain for a period of three months, after primary operation, and at least six months after operation for recurrence. The cases will automatically be graded for this period, but even so care must be taken to see that strain is eliminated as the reason for the grading is apt to be forgotten.’
Grading: Cases were graded following operation in difficult cases, in the older men, and because of recurrence. At May 1942 only nine cases of an average age of thirty-seven years were graded for base duty.
By March 1943 seven graded men had been sent back to New Zealand for non-medical reasons and seven of an average age of thirty-five were at that time graded for base duties. Two had refused operation, for one an operation was not advised, one was awaiting operation, one was a recurrence, and two were graded as a precaution. Details were as follows:
Umbilical Hernia and small R. Bubonocele. Refused operation. Age, 38 years.
Operation Bilateral in New Zealand, 1940. Recurrence of small bulge, one just outside ring, other in ring. Refused operation. Age, 42 years.page 409
Large Indirect Hernia. Operation September 1942. Temporarily graded for rest. Age, 23 years.
Bubonoceles bilateral, also osteoarthritis knees, fat, poor subject. No operation advised. Age, 40 years.
Bilateral operation in New Zealand. Operation NZEF November 1941. R. side. In November 1942 recurrence noted size of pigeon's egg. Sac small and difficult to find. Cord displaced in front of aponeurosis. Also has syphilis. Age, 41 years.
L.I.H. Operation advised recently. Not yet performed. Age, 37 years.
Operation in New Zealand (1932 R.I.H., 1935 R. & L.I.H.). Operation in NZEF, R.I.H. September 1941. Silk repair, satisfactory result but graded as a precaution. Age, 26 years.
The conclusions reached in May 1942 after a review of the cases sum up the position satisfactorily: ‘The results show clearly that inguinal hernia, except for the period of disability consequent on the performance of the operation and the convalescence therefrom, is not of any serious importance in 2 NZEF’.
There were about 10 men graded for hernia every month, including cases graded temporarily following operation. There were normally about 30 men on the graded list at one time, 23 actually in the last list of men graded for all conditions, a very small proportion of the whole.
Invaliding: Older patients were often sent back to New Zealand, especially if they had some added disability. Up till March 1943 only seven cases had been sent back to New Zealand, their ages being 29, 39, 42, 49, 50, 52, 52. During the rest of the war in the MEF and CMF another 24 cases were invalided back to New Zealand—a total of only 31 in 2 NZEF for the whole period of the war.
The conditions present in hernia may be:
A congenital indirect sac starting at the internal abdominal ring and passing down the canal for a variable length, the maximum extending to the scrotum and being continuous with the tunica vaginalis.
Weakness in the musculature of the abdominal wall, especially in the region of the inguinal canal.page 410
Attenuation of the structures of the inguinal canal with consequent stretching and bulging of the abdominal wall in this region.
Direct herniation due to the bulging of the peritoneum through weakened areas of the inguinal canal.
It is obvious that the operative measures to be adopted must vary with the conditions present in the individual case. In the simple indirect hernia the removal of the sac should bring about cure.
When the musculature is much weakened and, in consequence, stretching and bulging of the inguinal region has taken place, with eventually the formation of a direct hernial sac, the simple removal of this sac cannot be expected to bring about permanent repair. Some tautening and strengthening is essential. It is well known that this function is carried out in the body by the fascial layers, so it is natural to employ methods which utilise the fascial tissues available. Unfortunately the transversalis fascia is often fragmentary, especially in the worst cases.
Overlapping of the external oblique aponeurosis is simple and of considerable value. The rectus sheath can often be utilised to strengthen the weak inner part of the canal, either by turning back a flap or by splitting the sheath and suturing the lower part to Poupart's ligament. A combination of methods is frequently available and useful.
The utilisation of muscle in the repair is against surgical principles except in so far as the alteration in insertion may make the muscular action more efficient. This would be brought about by the alteration in the insertion of the conjoint tendon, bringing the tendon lower to cover over the weak internal portion of the canal. The tendon may be partly split to enable this to be done or simply stitched lower down to the pubis.
The stitching of the muscular part of the conjoint tendon to Poupart's ligament as in Bassini's operation damages the muscles and interferes with their action, and can only be effective by the formation of fibrous tissue at the site of suture and the production of a new fascial layer.
The use of fascial strips provides support by the incorporation of the strips in the tissues and the formation of fresh fibrous tissue around them, and the silk lacing produces the same kind of result, encouraging the production of much fibrous tissue.
Essentially, operation in all but the simplest cases entails a plastic repair of the inguinal part of the abdominal wall, if possible brought about without interference with muscular action. Fortunately the proportion of simple cases is high. There are many types of page 411 herniation and many degrees of severity and no one technique can deal with them all. It is essential to suit the technique to the individual case and apply sound general surgical principles. One must occasionally admit that no surgical repair is possible and that other methods of partial relief are all that can be offered the patient.
Operative Treatment in 2 NZEF
This was carried out in the New Zealand base hospitals by any of the surgeons available. When the hospitals were fully occupied with battle casualties, the hernia cases were deferred, both from the point of view of space, and also of possible infection. With the large numbers of surgeons concerned there was no uniformity of operative technique, but the following four main types of operation were carried out:
Simple removal of the sac without any alteration in the ordinary anatomy of the inguinal canal. This technique was favoured in the early case of indirect hernia in young men, where no undue weakening of the musculature and fascial layers had taken place.
Removal of the sac and in addition some reinforcement, its form depending on the case and on the surgeon, by repairs of the Bassini type, by suturing of the transversalis fascia, especially round the internal ring, by suturing the conjoint tendon to Cooper's ligament, by overlapping the external oblique aponeurosis, by utilising a flap from the rectus sheath to suture to Poupart's ligament, all methods to strengthen the wall of the inguinal canal, either with or without displacement of the cord.
Silk Repair: The utilisation of strong silk to lace up the posterior wall of the inguinal canal, and especially the region of the internal abdominal ring, was much in vogue at the beginning of the war, as a simpler and just as efficient method as that of the utilisation of fascial strips. The method was recommended by Major-General Ogilvie, Consultant Surgeon MEF, who kindly demonstrated it on two cases in the New Zealand base hospital in Helwan. Unfortunately, under the conditions sepsis was found to occur in a sufficient number of cases to make the employment of silk undesirable, and the operation was later prohibited in the British Army. When sepsis did arise the deeply embedded silk caused severe local disturbance and was very difficult to remove.
Fascial Repair: This was not often carried out except by the utilisation of viable fascia in the canal itself, such as a flap from the rectus sheath. Cases requiring this type of operation would generally be in the older age group. In this group, operation in the army overseas was deemed inadvisable for the more severe cases, who were graded or sent back to New Zealand.page 412
Arrangements were made to have men suffering from hernia undergo a course of physical exercises to strengthen the abdominal musculature, both before and after operation. This was found to shorten the period of convalescence, and was thought to make recurrence less likely.
In the Middle East Force the question of the frequency of recurrence caused much comment at one time, and investigations were carried out to find the cause. It was considered that unsatisfactory operative technique had been responsible for some of the recurrences.
It was ascertained that many of the recurrences were due to the inability to remove the sac satisfactorily, and in some cases the original sac was intact, and there was dissatisfaction with the Bassini and similar techniques.
There was a tendency to rely on the simple removal of the sac and not to interfere with the normal functioning of the musculature of the inguinal canal. It was emphasized, however, that operative repair of inguinal hernia was not always an easy matter to be delegated to the young untrained surgeon, but that it was highly important that the first operation performed be carried out with great care by a surgeon of experience who could add, as necessary for the individual case, some extra form of plastic repair, as little damaging as possible to the functioning musculature of the inguinal canal. The problem, fortunately, did not apply so much to 2 NZEF, in which there were comparatively few recurrences. Two reviews of the cases in the 2 NZEF were made by the consultant surgeon, one in May 1942 and the other in March 1943.
By May 1942 there had been 228 operations for primary hernia with two recurrences, one a sliding hernia on the right side and the other following a post-operative chest complication associated with a cough. There were five recurrences following pre-war operations performed in New Zealand. Six cases had had one recurrence and one case had had two recurrences on one side.
By March 1943 there had been a total of 361 operations for inguinal hernia in the following categories:
|Inguinal Hernia: Indirect or unspecified||330|
|Inguinal Hernia: Direct||10|
|Inguinal Hernia: Fascial repair||2|
|Inguinal Hernia: Recurrent||19|
It was noted that cases operated on for recurrence were very liable to break down again, thus denoting a marked weakness of page 413 the abdominal musculature. For instance, one case had an operation for bilateral hernia in 2 NZEF with a history of Battle's incision eighteen years previously and a right hernia operation eleven years previously. Operation on the right side for recurrence took place in April and September 1942, the last being a repair by silk which was effective; there was still a slight recurrence on the left side.
Number of Operations
While an exact record is not available of the number of operations for hernia performed in 2 NZEF it has been possible to compute an approximate total, using the survey made in March 1943 showing 361 operations and the record of hernia patients admitted to hospital for hernia subsequent to that date. It seems that there were about 725 operations altogether, as shown in the following table (the recurrence rate for the second period is estimated):
|Operated on to March 1943||342||19||361|
|Admitted to hospital Mar 43–Dec 45||344||20||364|
Experiences in British Army in United Kingdom 1
A statistical review of cases of hernia in the British Army in the United Kingdom from mid-1943 to mid-1944 has disclosed much of interest which is partly comparable to 2 NZEF experience. In terms of man wastage among males, hernia contributed more to hospitalisation in the army in the United Kingdom than any other single diagnostic category, and indeed more than the entire class of psychiatric disorders. In addition, refusal of operation entailed wastage of manpower in the higher categories as these men had to be down-graded. In the one year there were 6874 first hernia operations and 846 operations for recurrence, an annual rate of 5 per 1000 strength. The period in hospital was protracted, the mean stay in hospital and convalescent depot being three months. Practically all cases were returned to full duty. The relative incidence of operation at different ages varied little, but the incidence of discharge increased with advancing age and very steeply in the terminal age groups.
The relative incidence of the different types of hernia was indirect 86; direct 10; femoral 4.
Recurrences were much more common following simple removal of the sac and less frequent following repair by fascia. A majority page 414 of the recurrences following indirect hernia were still indirect and resulted from failure to excise the sac, and more commonly followed the simpler form of operation. The majority of the recurrences occurred within one year.
The final conclusion arrived at by the reviewers was that ‘(a) after about one out of every eight primary operations the original condition reappears within twelve months; (b) the overwhelming majority of such recurrent cases are the result of an operation for the performance of which a relatively modest level of professional skill is perhaps too commonly deemed to suffice.’
The review throws valuable light on the problem. It confirms our New Zealand experience in the Middle East that operation in suitable cases can be relied on to make a man fit for front-line duty. The opinion is also given that many recurrences are due to inability to find, or satisfactorily deal with, the sac—a sign of poor and inexpert surgery.
The 2 NZEF period of three months before return to full duty following operation is also shown to have been the standard in the United Kingdom. Multiple recurrences were shown to be fairly common. This upholds the 2 NZEF routine of grading and invaliding such men, generally in the older age group, instead of subjecting them to operation, thus enabling their manpower to be better utilised and saving hospital accommodation overseas.
War Pensions Survey
A survey was made in May 1952 of the records of all ex-servicemen who had applied for pension or had been graded below Grade I on discharge, and including those in whom hernia was diagnosed at discharge, although the man himself may have had no prior knowledge of any abnormality and certainly of no disability. In all there were 562 cases, including those whose hernia had been repaired but who complained of minor symptoms. The records available for these cases revealed that there were 666 herniations in men whose theatres of service were:
|Army—2NZEF MEF and CMF||261||186|
|2 NZEF IP||84|
Of the 261 men with service in 2 NZEF MEF the herniations were: (a) present before going overseas, 14; (b) operated on prior to enlistment with recurrence overseas, 18; (c) originated overseas, 154; (d) discovered on discharge in New Zealand, 65; page 415 (e) occurred after discharge, 10. An actual herniation was not present in all the cases in groups (a), (b), and (c)—some men who had been operated on successfully complained of minor symptoms.
The types of hernia noted in these men were: inguinal hernia—right, 85; left, 64; bilateral, 78 (i.e., 39 men); femoral, 8; incisional, 12; umbilical, 6; epigastric, 7; diaphragmatic, 1.
The 227 cases of inguinal hernia were dealt with as follows:
|No operation (hernia persists)||60|
|Operated in MEF||41||25|
|Operated in UK||8||4|
|Operated in Germany||11||7|
|Operated in NZ||107||17|
Of the recurrences 35 were repaired satisfactorily, mostly with one operation, but 18 were unrelieved, four of whom had one further operation, and one had four further operations.
Of the 25 recurrences from MEF, 2 were repaired satisfactorily in the Middle East and the majority of the remaining 23 in New Zealand. The 23 cases represented about 3 per cent of the 725 cases dealt with in 2 NZEF in the Middle East, a very satisfactory result which can be attributed to a wise selection of cases for operation, and also to adequate surgery. Of the 725 cases, only 41 were graded below Grade I on discharge.
A total of 84 cases was recorded from the Pacific Force, to which some Grade II men were sent and from which relatively more men were invalided to New Zealand.
A total of 186 hernias were recorded in homeservicemen, and of these 49 were present on enlistment; 14 recurred after a pre-service operation; 110 developed during service; 12 were discovered at discharge; and 1 developed after discharge. Some 104 were operated on, with 32 recurrences, of which 12 remained unrepaired, 7 after one, 3 after two, and 2 after three operations. The recurrence rate was thus 30 per cent, and 11 per cent of the total cases were eventually unrelieved. The poorer results naturally arose from the higher age groups and lower-graded men who composed the Home Service force. The 135 men who had served overseas, but who had their only operative treatment subsequently in New Zealand, had 26 recurrences (only 20 per cent), and only 7 (5 per cent) were finally unrelieved. Altogether the results appear satisfactory, though in some cases several operations were required, with a consequently long period of recovery from disability. The overall picture is, firstly, of the rejection by the page 416 army of nearly 2 per cent of recruits because of the presence of hernia; secondly, that of the men sent overseas 1 per cent developed hernia, of whom the majority were operated on with success so that they continued to serve overseas, as also did many who were graded without receiving any operative treatment. Only a very small number were invalided back to New Zealand because of hernia, and most of these had other disabilities or were in the oldest age group. Operation overseas was largely restricted to younger men with good musculature, the older men being graded for lighter work, generally at the Base. This resulted finally in only 3 per cent of the operated cases showing up as recurrences on arrival back in New Zealand. This was in contrast to overseas cases first operated on after their return to New Zealand when 20 per cent had an initial recurrence, but of whom only 5 per cent remained unsatisfactory after further operation. In all primary operations in New Zealand (201 cases) the recurrence rate was 19 per cent, while in the 342 cases operated on in 2 NZEF MEF to March 1943 the recurrence rate was under 6 per cent.
Of the 163 hernias occurring in all services where the interval times between operation and recurrence were given, 77 recurred within one year, 31 within two years, 13 within three years, and 42 after three years. There was only an odd case of recurrence after eight years.
The position in 1952 with the 531 herniations in army cases coming in the purview of the War Pensions Boards was that 351 had been operated on, and of these, 104 had had recurrences, which were all repaired except for 33. Many of the 33 declined further surgery after the first operation. Hernia was still present in 180 cases which had not been operated on.
Of all cases, relieved and unrelieved, only 46 (18 from the Middle East and 21 homeservicemen among them) were receiving a pension in 1952, and of these, 36 were receiving 20 per cent or under. Some of the pensions were for weak or painful scars, and only one was for atrophied testis. The final pension liability is remarkably low, and shows that the army can use men with the abnormality of hernia without the State eventually being required to pay any large amount in pensions.
Recommendations for the Future
In the light of New Zealand's experience in the 1939–45 War one would recommend:
All young and otherwise fit recruits with primary hernia conditions should be operated on by a competent surgeon as they will be rendered fit for front-line service.page 417
All patients should have physical exercises to improve the abdominal musculature both before and after operation.
A period of three months should be laid down as necessary for convalescence following operation before posting to the army or return to full duty.
In the older age groups all men with good abdominal musculature in whom satisfactory repair can be carried out should be operated on and given an extra period of three months on light duty before posting or return to full duty.
Cases with feeble abdominal musculature, especially in the older group, and recurrent cases, should not be accepted in the army. If already in the army they should not be operated on but graded for base duties or discharged according to their usefulness to the army.
In the young men with good abdominal musculature the adequate removal of the sac should give a satisfactory result.
There are no data available to show that any of the numerous methods of strengthening the inguinal canal can be deemed to be superior to others or able to give assurance against recurrence. However, many of the methods are of value when used intelligently.
Repair by fascial grafts is satisfactory in the more severe types of hernia, but is liable to more severe disturbance in the presence of sepsis, and again, does not give a guarantee against recurrence.
Repair by silk darning was found unsuitable for use in the army owing to the severe disturbance associated with infection when that did occur.
The operation for hernia is one of considerable importance in the saving of manpower in the army. It demands ability and experience in the operator and should be looked upon as an operation calling for the employment of differing techniques according to the variation in the condition of the individual hernia, and not for a stereotyped routine procedure.
1 From Statistical Report on the Health of the Army, 1943-45.