15. Dermofasciectomy

15.1 Introduction

Piulachs and Mir Y Mir (1952) have suggested that the risk of recurrence after surgery for Dupuytren's disease is reduced and probably eliminated when the involved skin above the retracted fascia is replaced by skin grafting. Gordon (1957), in reporting a large series of operations, mentioned that grafts had been applied on 13 hands and that the grafted areas remained free of disease.

The empirical clinical observation that recurrence does not occur beneath a free skin graft led Hueston to propose the elective excision of skin involved in recurrent Dupuytren's disease in 1962 in the belief that the dermis exerts some kind of control on the disease process. He excised the skin over the proximal segment of the digit from one neutral line to the other. The idea was taken up by Tubiana (1963) and large series have since been presented by Tonkin (1984) and Iselin (1985, 1990).

The proposal by Hueston to apply dermofasciectomy, the discarding not only of the Dupuytren's tissue but also of the overlying skin, to the primary surgery in some selected patients in whom recurrences are highly probable came from the observation that secondary surgery is far more difficult. Indeed, recurrent Dupuytren's tissue arises from the remaining sub-dermal fibrofatty layer and extends to involve, not normally pre-existing aponeurotic structures as for a virgin mass, but the epineurium of the digital nerves, the fibrous flexor sheath and the joint ligaments. It is thus a far more difficult task technically to retain intact these essential anatomical structures during dissection of recurrent Dupuytren's disease than it is in the primary disease when these structures are rarely if ever directly invaded.

They are a few difficulties inherent in the application of skin grafts that prevent their systematic use in the treatment of Dupuytren's disease even though they provide a good protection against future evolution in the operated fingers:

The advantages of a lower recurrence rate have thus to be weighted against those potential problems.

15.2 Surgical technique

15.2.1 Full thickness skin grafts

Full thickness skin grafts are usually preferred for three reasons: they give a better cosmetic appearance in the hand, they provide a better protection in the palm which is submitted to all kinds of trauma and above all they do not retract.

The application of full thickness skin grafts requires a satisfactory bed at the end of the fasciectomy so that a complete take of the graft will occur. An intact fibrous flexor tendon sheath is required although, as claimed by Gonzalez (1985), the graft will take on the paratenon of a not too widely exposed flexor tendon. In 1985, Hueston still thought that it was absolutely necessary to keep the fibrous sheath intact and that if the flexor tendons were exposed the situation would be much more complex, perhaps requiring distal flap transfers. In 1990, he confirmed that the direct application of the graft on the paratenon is possible. By doing so, there is nevertheless an added risk of graft failure from flexor tendon movement and this is thus best avoided.

Hueston (1990) advises to take the full thickness skin graft from either the inner aspect of the same arm or from the groin. We have avoided to harvest the graft from the groin because the skin is thicker than on the arm and its take as a graft is therefore more difficult. Moreover the colour match is not always perfect. We have found that for small skin defects, the flexion crease of the elbow was a very good donor site: the skin is thin, the colour match is as good as possible and after a few weeks, the scar, parallel to the flexion, crease almost disappears.

15.2.2 Operation

Hueston exposes the Dupuytren's tissue through a longitudinal incision extending from the distal palmar crease to the middle phalanx or even to the distal interphalangeal joint or pulp level if the latter is flexed. He then elevates the skin even if pathological tissue is retained in it, until the fasciectomy is completed with intact neurovascular bundles and fibrous flexor sheath. The skin flaps are resected back to the mid axial line along the side of the digit with darts at each joint crease, to retain at these points the marginal scarline of the grafted defect at, or slightly behind, the midline axis of the digit. If the scarline junction of the grafted skin is even slightly anterior to the mid line, there will be, by the normal process of scar retraction, a longitudinal tension exerted anterior to the axis of the interphalangeal joint and the flexion deformity will be reproduced to some degree. Hueston advises to resect the skin flaps after the fasciectomy when one is sure that the tendon sheath is intact. It is usually easier to make the resection of the pathological fascia and of the overlying skin in one piece as we are now sure that a graft can be applied on the paratenon if the flexor sheath was damaged.

It is very important to avoid any blood collection beneath the graft as this would compromise its take. Tied over dressings are thus applied to ensure adequate pressure on the graft.

15.2.3 Postoperative treatment

The mobility of the operated finger is restricted by a Levame's extension spring that also maintains the correction of the contracture achieved at the end of the operation. Hueston immobilises the whole hand on a plaster volar slab for five days but in our opinion, this is too much immobilisation for too short a period. We have seen grafts that were perfect after five days and that became necrotic after mobilisation was allowed. A workable compromise is thus to use the 'elastic' immobilisation provided by the Levame's springs for ten days.

15.3 Indications

We have restricted the indications of dermofasciectomy to recurrences or to some very advanced primary cases with major skin retraction and shortage for which it would have been impossible to perform a segmental aponeurectomy . We have not followed Hueston's proposal to apply dermofasciectomy in some selected patients in whom recurrences are highly probable for several reasons:

It has thus been our attitude to propose a segmental aponeurectomy for all primary cases and for extensions of the disease where this operation is technically feasible and, on the other hand, to suggest a dermofasciectomy for all cases reoperated for a recurrence. This compromise offers several advantages:

Hueston (1985d) and Varian (1985) restrict skin grafting to the digit. We have adopted their view that there is no need to extend the skin excision proximal to the distal palmar crease, as a recurrent nodule in this area is rare, and furthermore, is unlikely to contract a finger that has been skin grafted, as there will be no fascial band running into the finger through witch the nodule could contract it.

15.4 Results

15.4.1 The patients

With the indications outlined above, we have performed 45 dermofasciectomies in 37 patients, 30 men and 7 women whose average age was 57.6 years (range 27 to 87). In 9 cases a dermofasciectomy on one ray for a recurrence was associated with a segmental aponeurectomy for an extension of the disease on other rays never operated before.

A family history of the disease was reported by 39 % of the patients. Although the unreliability of this information has already been discussed, this percentage is much higher than the one observed for segmental aponeurectomies (28.4 %).

Among the patients, 17.8 % were alcoholics, 0 % were under treatment for diabetes and 11.1 % had been or were under treatment for epilepsy. In 8.9 % of the cases there was a history of local trauma. These proportions are very different from those observed in segmental aponeurectomies: 8.3 %, 3.1 %, 5.1 % and 10.6 % respectively.

33 (73.3 %) of the 45 hands had undergone a previous operation on the same or other rays (1 or 2.2 % showed an extension of the disease, 23 or 51.1 % a recurrence and 9 or 20 % a combination of the two). These proportions are of course very different from those reported for segmental aponeurectomies due to the selection of the patients.

Fourteen (50 %) of the 28 patients for whom the information was recorded, showed signs of involvement of ectopic sites by the disease. For segmental aponeurectomies, that percentage was 26.7.

An involvement of both hands was noted in 33 patients on 35 (94.3 %). For segmental aponeurectomies, that proportion was 85.5 %.

15.4.2 Preoperative evaluation

The pre- and postoperative evaluation was done using the same parameters as for segmental aponeurectomy. Tubiana's grade

The mean preoperative Tubiana's grade was 4.4 (SD 2.99, range 1 to 13). For segmental aponeurectomies the mean grade was 3. Impairment of function

The mean preoperative impairment of function was 10.1 % (SD 8.3, range 1 to 41). For segmental aponeurectomies it was 6.1 %. Involved rays

The median number of involved rays was 2. The distribution of the number of involved rays is summarised in table 1.

Table 15-1: Distribution of the number of involved rays

The frequency of involvement was not the same for each ray (table 2). The fifth ray was by far the most frequently involved. This was to be expected since recurrences are much more frequent in the little finger as we have already seen.

Table 15-2: Frequency of involvement of each ray

15.4.3 Postoperative evaluation Tubiana's grade

The mean postoperative Tubiana's grade was 1.68 (SD 1.39, range 0 to 5). The mean improvement was 60.7 % (SD 24.8, range 0 to 100). For segmental aponeurectomies, the mean improvement was 84.2 %. Impairment of function

The mean postoperative impairment of function was 3.41 % (SD 3.77, range 0 to 16). The mean improvement was 68.5 % (SD 21.2, range 25 to 100). All cases were thus functionally improved by the operation even those which developed a complication. For segmental aponeurectomies, the mean improvement was 88.4 %. A summary of the pre- and postoperative values compared to those observed for segmental aponeurectomies is presented in table 3.

Table 15-3: summary of the pre- and postoperative observations

15.4.4 Complications

Ten cases (22.2 %) developed one or more complications. Haematoma

One haematoma (2.2 %) was observed under a skin graft in spite of the tie-over dressing. Infections

Two cases (4.4%) developed an infection in relation with a partial necrosis of the skin graft. Skin (graft) necrosis

Eight cases (17.8 %) had a partial or total necrosis of the grafted skin. Five of those cases are not related to an infection or to the development of an haematoma but appeared after the removal of the tie-over dressing, when the mobilisation of the finger was permitted a few days after the operation. This is the reason why I now immobilise the finger by an extension splint for about ten days. Most late necrosis developed at the junction between the graft and the hardened palmar skin at the level of the metacarpophalangeal joint. Nerve lesions

One digital nerve was damaged during the dissection in spite of the wide exposure. The lesion was recognised during the operation but the fibrous infiltration of the nerve was such that a suture was not performed. No neuroma developed later. Sympathetic dystrophy

Two cases (4.4 %) developed a sympathetic dystrophy that imposed a very long revalidation. Even those cases were improved by the operation.

15.4.5 Recurrences

One recurrence, coming from the tendon sheath, has been observed under a skin graft.

15.5 Discussion

We have used dermofasciectomy for recurrences or very severe contractures in primary cases as was indicated before. We are thus faced with a selected high risk group of patients whose parameters reflect their difference with the average patient suffering from Dupuytren's disease:

Faced with more severe conditions, we expect less satisfactory results and that is what we observed:

The comparison of the results with other published studies is difficult because there is a great variability in the operated cases and the selection of the patients. From his multicentric review, McFarlane et al. (1990b) reports the results of 81 dermofasciectomies in 77 patients. He gives no information about the selection of the cases or about previous operations. In his review, none of the operated fingers achieved a perfect result and the percentage of complications (37 %) is even higher than in my series. Varian (1993) has summarised his results on 76 operations. His patients were younger than in this series (mean 49 years) and the majority was operated for a recurrence of the disease (65 % compared to 73 % in this study). The results seem to be comparable to those achieved in this review since the average improvement of the contracture was 67 % (69 % in this study). He reports less complications but had to perform secondary operations to correct skin or scar contractions. He also observed one true recurrence under the skin graft.

Even if those results were observed in the worst cases, this probably means that dermofasciectomy, an ultra-radical procedure as Hueston calls it, should not be proposed lightly to all patients just to avoid a possible recurrence. The risk of complication is high and is more related to the procedure than to the severity of the cases. Hueston (1990b) himself insisted on this aspect of the problem and insisted on the fact that this operation was rarely required.

A single true recurrence was observed in this review. This observation is rather exceptional. Hueston (1990b) reports one single case in his large experience with this technique. Even if dermofasciectomy does not eliminate recurrences totally, the observed risk is much lower than with segmental aponeurectomy for example. This is all the more remarkable that this low percentage was observed in a high risk population.

15.6 Conclusion

Dermofasciectomy allows a very good if not perfect control of recurrences but there is a price to pay in the form of much more complications.

This observation reinforces my opinion about the choice of the adequate procedure in the treatment of Dupuytren's disease: