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Enzymic fasciotomy
Enzymic Fasciotomy--John T. Hueston
ENZYMIC FASCIOTOMY JOHN T. HUESTON, Melbourne It is five years since Bassot (1965) first reported his technique of "exerese pharmodynamique" for Dupuytren's Contracture--with illustrations of two patients whose gross flexion deformity had been completely corrected. In June, 1969, he reported the results of thirty-four patients, with impressive correction of severe deformities by this non-surgical method. Therefore it appeared essential to investigate this alternative to surgery and to place it in some perspective with relation to more orthodox surgical techniques. in this method, trypsin is injected with local anaesthetic and hyaluronidase, at points along the length of the band and nodule. After fifteen minutes, forcible extension is applied to rupture the deforming mechanism. We can confirm that in most cases fu,ll passive extension can be obtained (Fig. 1 and Fig. 2).
Fig. 1 Contracture affecting ring finger. Fig. 2 Ring finger extended after injection and correction. METHOD
Bassot's formula as published (1969) is-Trypsine: 2.5 m.g.; Alphachymotrypsine: 7.5 nag.; Hyaluronidase: 750 units T.R.U.; Thiomucase: 300 units T.R.A.; Lignocaine 2%; 20 cc. The simplified formula we have been forced to use by unavailability of supplies has been-Trypsin: 2.5 mg.; Hyaluronidase: B.P. 1,500 units; Xylocaine 2°/° plain:-20 mls. It is let' that a very high concentration of trypsin can safely be used and in one of our cases 50 mgm. was used. Injections are made at several points long the band and nodule. It may be suggested that this-~needling may in fact be producing a traumatic or surgical fasciotomy; but controls with saline have failed to be effective. On forcible extension, an audible cracking occurs, which is usually the palmar band being ruptured. The interphalangeal bands give the impression of stretching and tearing rather than frankly separating and do not leave such a palpable defect as is usual when the palmar band is ruptured. The correction is retained by a plaster 38
Vol. 3
No. 1
1971
Enzymic Fasciotorny--John T. Hueston
slab for two to five days and then full movements are easily resumed. The plaster is used at night for two weeks. Rupture of the skin has occurred in severely flexed cases with soft adherent skin but these have healed rapidly even when not grafted. DISCUSSION
Bassot plans his attack on what he regards as the essential three histological components of Dupuytren's contracture--fibroblastic proliferation, alteration and over-production of ground substance and contraction of collagenous tissues--he mixes proteolytic and anti-inflammatory enzymes (trypsine and alphachymotrypsine) with enzymes to depolymerize and spread the ground substance (thiomucase and hyaluronidase) and Lignocaine which, in addition to being local anaesthetic, may assist by decreasing the local reflex reaction ("neuroplegic" action). Our investigations into the actual effect of this mixture on the tissues are based on (a) excision of the Dupuytren's tissue after injection and rupture, with histological studies, and (b) injection of recent cadaver material. Macroscopically when the ruptured tissue is exposed the longitudinal fibres are seen to have been torn cleanly in the palm, leaving a lozenge shaped defect through which the intact synovial system of the flexor tendons can be seen. There has been little haemorrhage, partly because a tourniquet was almost immediately applied to allow resection of the specimen, and partly because only the poorly vascular band itself has been ruptured, with local oedema from the injection but little evidence of injury to adjacent tissues. Microscopically the margins of the point of rupture in the band appear to be staining normally with no cellu.lar nuclear changes possibly because time has not been allowed for these to occur. Certainly there has been no instant massive chemical necrosis. Histological sections of cadaver muscle, tendon and nerve thus injected have shown no significant changes. The Trypsin is apparently at a safe concentration and the spreading agent ensures that its action is likely to be measured in minutes rather than hours. There is evidence of a regional injury over the following three to four days, with moderate swelling of the dorsum of the hand and of the injected finger-probably due partly to liberation of tissue breakdown products from the enzyme action and partly purely traumatic. When exposure and formal fasciectomy has been proceeded with, the wound has had a more prolonged oedematous phase passage before final healing has occurred, as usual, at two weeks. It is too soon to assess our personal series of twelve cases and since three of these have had immediate fasciectomies to provide tissue for study our material is very restricted. While full metacarpophalangeal correction is the rule, there has been difficulty in obtaining sufficient traction on digital sections of the band, after the prior rupture of the palmar segment of the band to achieve rupture of the interphalangeal bands in three patients. Bassot repeats his injections and traction on several occasions over a week or two until all residual bands have been eliminated. We have repeated the injections after one month for residual elements with some benefit. Certainly full painless movements are present from two to three days after correction. Vol. 3
No. 1
1971
39
Enzymic Fasciotomy--John T. Hueston
There has been no evidence of traction injury to digital nerves. Rupture of the soft skin in the flexure creases after correction of severe deformity has been the major complication but its significance on the final result appears to be negligible. From our findings it is suggested that "enzymic fasciotomy" is a more accurate description of what occurs in this procedure than the "pharmacodynamic excision" of Bassot. There appears to be only partly a dissolution of tissue, bu,t its main effect is to allow a facilitation of traumatic rupture. The consequences of rupture follow in much the same way as after a surgical rupture by fasciotomy. COMMENT
Until much greater experience has been obtained with this method and an assessment of the late results has been made the risk of advocating such a simple method is that many practitioners may attempt it without a full appreciation of the underlying condition of Dupuytren's contracture. I would recommend its u s e i n a few selected instances, namely (i) Where the patient is not medically fit even for regional anaesthesia, this local anaesthetic technique in the hand has allowed complete correction of metacarpophalangeal deformity. (ii) Extensive multifocal disease in an elderly person where extensive surgery is preferably avoided. (iii) in severe flexion deformity to provide metacarpophalangeal correction as a preliminary to a definitiye fasciectomy of the fingers; that is to say in the same ro'l~ as Bunnell recommended preliminar~surgical fasciotomy. There is little reason to exp~Ct that this method will have any different effect than surgical fasciotomy on the disease process. It is in the elderly with discrete mature bands that atrophy and apparently permanent resolution of the deforming mechanism is sometimes seen after accidental traumatic rupture or after a well performed fasciotomy. Shrinkage of digital nodules occurs when the longitudinal traction is relieved by fasciotomy and the recent recommendation by Gonzales (1969) that open digital transection of the deforming band-nodule mechanism be retained by insertion of a graft is based on his observation that resolution of the pathological process occurs on release of longitudinal •tension, It will require further study to determine whether these enzymes actually facilitate the natural resolution of the abnormal tissue in Dupuytren's contracture after release of the longitudinal tension. CONCLUSION Enzymic fasciotomy appears to offer an alternative to surgical fasciotomy in selected patients. REFERENCES
BASSOT, M. J. (1965)~ Traitement de la rnaladie de Dupuytren par ex6r6se pharmacodynamique isol6e ou compl6t6e par un temps plastique uniquement cutan6. Lille Chirurgicat 20: 38. BASSOT, J. (1969) Traitement de la maladie de Dupuytren par ex6r~se pharmaco-dynamique bases physio-biologiques-Technique. Gazette des Hopitaux No. 16, 10 Juin, 557. GONZALEZ, R. I. (1969) Flexion deformities of the Fingers. Current Practice in Orthopaedic Surgery 4: 167. 40
Vol. 3
No. 1
1971
ENZYMIC FASCIOTOMY JOHN T. HUESTON, Melbourne It is five years since Bassot (1965) first reported his technique of "exerese pharmodynamique" for Dupuytren's Contracture--with illustrations of two patients whose gross flexion deformity had been completely corrected. In June, 1969, he reported the results of thirty-four patients, with impressive correction of severe deformities by this non-surgical method. Therefore it appeared essential to investigate this alternative to surgery and to place it in some perspective with relation to more orthodox surgical techniques. in this method, trypsin is injected with local anaesthetic and hyaluronidase, at points along the length of the band and nodule. After fifteen minutes, forcible extension is applied to rupture the deforming mechanism. We can confirm that in most cases fu,ll passive extension can be obtained (Fig. 1 and Fig. 2).
Fig. 1 Contracture affecting ring finger. Fig. 2 Ring finger extended after injection and correction. METHOD
Bassot's formula as published (1969) is-Trypsine: 2.5 m.g.; Alphachymotrypsine: 7.5 nag.; Hyaluronidase: 750 units T.R.U.; Thiomucase: 300 units T.R.A.; Lignocaine 2%; 20 cc. The simplified formula we have been forced to use by unavailability of supplies has been-Trypsin: 2.5 mg.; Hyaluronidase: B.P. 1,500 units; Xylocaine 2°/° plain:-20 mls. It is let' that a very high concentration of trypsin can safely be used and in one of our cases 50 mgm. was used. Injections are made at several points long the band and nodule. It may be suggested that this-~needling may in fact be producing a traumatic or surgical fasciotomy; but controls with saline have failed to be effective. On forcible extension, an audible cracking occurs, which is usually the palmar band being ruptured. The interphalangeal bands give the impression of stretching and tearing rather than frankly separating and do not leave such a palpable defect as is usual when the palmar band is ruptured. The correction is retained by a plaster 38
Vol. 3
No. 1
1971
Enzymic Fasciotorny--John T. Hueston
slab for two to five days and then full movements are easily resumed. The plaster is used at night for two weeks. Rupture of the skin has occurred in severely flexed cases with soft adherent skin but these have healed rapidly even when not grafted. DISCUSSION
Bassot plans his attack on what he regards as the essential three histological components of Dupuytren's contracture--fibroblastic proliferation, alteration and over-production of ground substance and contraction of collagenous tissues--he mixes proteolytic and anti-inflammatory enzymes (trypsine and alphachymotrypsine) with enzymes to depolymerize and spread the ground substance (thiomucase and hyaluronidase) and Lignocaine which, in addition to being local anaesthetic, may assist by decreasing the local reflex reaction ("neuroplegic" action). Our investigations into the actual effect of this mixture on the tissues are based on (a) excision of the Dupuytren's tissue after injection and rupture, with histological studies, and (b) injection of recent cadaver material. Macroscopically when the ruptured tissue is exposed the longitudinal fibres are seen to have been torn cleanly in the palm, leaving a lozenge shaped defect through which the intact synovial system of the flexor tendons can be seen. There has been little haemorrhage, partly because a tourniquet was almost immediately applied to allow resection of the specimen, and partly because only the poorly vascular band itself has been ruptured, with local oedema from the injection but little evidence of injury to adjacent tissues. Microscopically the margins of the point of rupture in the band appear to be staining normally with no cellu.lar nuclear changes possibly because time has not been allowed for these to occur. Certainly there has been no instant massive chemical necrosis. Histological sections of cadaver muscle, tendon and nerve thus injected have shown no significant changes. The Trypsin is apparently at a safe concentration and the spreading agent ensures that its action is likely to be measured in minutes rather than hours. There is evidence of a regional injury over the following three to four days, with moderate swelling of the dorsum of the hand and of the injected finger-probably due partly to liberation of tissue breakdown products from the enzyme action and partly purely traumatic. When exposure and formal fasciectomy has been proceeded with, the wound has had a more prolonged oedematous phase passage before final healing has occurred, as usual, at two weeks. It is too soon to assess our personal series of twelve cases and since three of these have had immediate fasciectomies to provide tissue for study our material is very restricted. While full metacarpophalangeal correction is the rule, there has been difficulty in obtaining sufficient traction on digital sections of the band, after the prior rupture of the palmar segment of the band to achieve rupture of the interphalangeal bands in three patients. Bassot repeats his injections and traction on several occasions over a week or two until all residual bands have been eliminated. We have repeated the injections after one month for residual elements with some benefit. Certainly full painless movements are present from two to three days after correction. Vol. 3
No. 1
1971
39
Enzymic Fasciotomy--John T. Hueston
There has been no evidence of traction injury to digital nerves. Rupture of the soft skin in the flexure creases after correction of severe deformity has been the major complication but its significance on the final result appears to be negligible. From our findings it is suggested that "enzymic fasciotomy" is a more accurate description of what occurs in this procedure than the "pharmacodynamic excision" of Bassot. There appears to be only partly a dissolution of tissue, bu,t its main effect is to allow a facilitation of traumatic rupture. The consequences of rupture follow in much the same way as after a surgical rupture by fasciotomy. COMMENT
Until much greater experience has been obtained with this method and an assessment of the late results has been made the risk of advocating such a simple method is that many practitioners may attempt it without a full appreciation of the underlying condition of Dupuytren's contracture. I would recommend its u s e i n a few selected instances, namely (i) Where the patient is not medically fit even for regional anaesthesia, this local anaesthetic technique in the hand has allowed complete correction of metacarpophalangeal deformity. (ii) Extensive multifocal disease in an elderly person where extensive surgery is preferably avoided. (iii) in severe flexion deformity to provide metacarpophalangeal correction as a preliminary to a definitiye fasciectomy of the fingers; that is to say in the same ro'l~ as Bunnell recommended preliminar~surgical fasciotomy. There is little reason to exp~Ct that this method will have any different effect than surgical fasciotomy on the disease process. It is in the elderly with discrete mature bands that atrophy and apparently permanent resolution of the deforming mechanism is sometimes seen after accidental traumatic rupture or after a well performed fasciotomy. Shrinkage of digital nodules occurs when the longitudinal traction is relieved by fasciotomy and the recent recommendation by Gonzales (1969) that open digital transection of the deforming band-nodule mechanism be retained by insertion of a graft is based on his observation that resolution of the pathological process occurs on release of longitudinal •tension, It will require further study to determine whether these enzymes actually facilitate the natural resolution of the abnormal tissue in Dupuytren's contracture after release of the longitudinal tension. CONCLUSION Enzymic fasciotomy appears to offer an alternative to surgical fasciotomy in selected patients. REFERENCES
BASSOT, M. J. (1965)~ Traitement de la rnaladie de Dupuytren par ex6r6se pharmacodynamique isol6e ou compl6t6e par un temps plastique uniquement cutan6. Lille Chirurgicat 20: 38. BASSOT, J. (1969) Traitement de la maladie de Dupuytren par ex6r~se pharmaco-dynamique bases physio-biologiques-Technique. Gazette des Hopitaux No. 16, 10 Juin, 557. GONZALEZ, R. I. (1969) Flexion deformities of the Fingers. Current Practice in Orthopaedic Surgery 4: 167. 40
Vol. 3
No. 1
1971