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Extensor indicis proprius transfer to supplement replacement arthroplasty of the rheumatoid hand
Extensor lndicis Proprius
Trans/er to Supplement Replacement Arthroplasty o/ the Rheumatoid Hand--S. L. Biddulph
E X T E N S O R INDICIS PROPRIUS T R A N S F E R TO S U P P L E M E N T R E P L A C E M E N T A R T H R O P L A S T Y OF T H E R H E U M A T O I D H A N D S. L. BIDDULPH, Johannesburg SUMMARY A new procedure is described to, cope with the rotatiun deformity so often seen after replacement ar'throplasty of the destroyed metacarpophalangeal joints in rheumatoid arthritis. The same procedure, in combination with a similar transfer to the ring and little fingers, but using extensor digiti minimi as the motor, can be used as: a suspension procedure to stabilise the early unstable metacarpophalangeal joint. Thirty hands have been treated with the longest follow-up of two-and-a-half years; so far the results have been encouraging.
INTRODUCTION The management of metacarpophalangeal joint destruction in Rheumatoid Arthritis has been greatly improved by the development of suitable replacement prostheses (Calnan 1971, Flatt 1968, Niebauer 1969, Swanson 1968b). However, several problems still remain unsolved and Swanson (1972) has recently enumerated the complications encountered after replacement arthroplasty. Among these, rotation of the index finger and recurrence of ulnar drift is particularly disabling as it precludes effective use of the hand. With the fingers moving away from the thumb, there is marked weakening of pinching power. In those cases where there is gross involvement of the thumb, especially if arthrodeses have been carried out in this digit, the thumb may not be able to reach the displaced index and middle fingers at all. The present paper describes a procedure which successfully counteracts or corrects this disability.
Fig. 1. Typical rotation deformity of the index finger following replacement arthroplasty of the metacarpophalangeal joints in rheumatoid arthritis. S. L. Biddulph, F.C.S.(S.A.), F.R.C.S., University of Witwatersrand, Johannesburg, South Africa. The Hand--Vol. 8
No. 2
1976
137
Extensor lndicis Proprius
Transfer to Supplement Replacement Arthroplasty oJ the Rheumatoid Hand--S. L. Biddulph
CLINICAL F E A T U R E S The principal deformity of the index finger referred to here is pronation of the entire digit; this may be further aggravated by the presence of ulnar drift at the metacarpophalangeal joint. Often the middle finger is involved in a similar, though milder, fashion (Fig. 1). Several factors are believed to contribute to this deformity: weakness and volar displacement of the first dorsal interosseous muscle (Tubiana, 1966); tightness of the ulnar intrinsic muscles (Flatt, 1968); radial deviation of the metacarpal bones upon the wrist (Shapiro, 1968); and capsular stretching due to inadequate splintage of the metacarpophalangeal joints after replacement arthroplasty (Swanson, 1969). O P E R A T I V E CORRECTION
The procedure to be described was designed to correct or prevent pronationrotation of the index finger. Extensor indicis proprius is used as the motor (Fig. 2); this tendon is split in two longitudinally, one tail being used to supply the index finger and the other the middle finger (Fig. 3). Each tendon slip is inserted into the base of the proximal phalanx just dorsal to the radial collateral ligament. The latter structure may be used to reinforce the attachment to the bone and adjacent capsule (Fig. 4). If the soft tissues are deficient, insertion may be directly into bone via a small drill hole. Tension should be equal to that of the normal extensor indicis proprius. Care should be taken not to foul the dorsal expansion at the site of suture as this may result in subsequent swan-neck deformity of the digit (Fig. 5). Post-operatively the hand is immobilised in a voluminous pressure dressing for a week. At this stage mobilisation is commenced (Figs. 2, 3, 4, 5). RESULTS
The operation has been performed on thirty patients with satisfactory prevention of the rotation deformity. The longest follow-up is two-and-a-half years, the shortest is four months. Fifteen cases have been followed up for more than one year. The tendon transfer appears to have several effects: (a) It produces supination of the index and middle fingers. (b) It lessens the extensor lag usually seen after replacement arthroplasty. (c) It strengthens radial deviation of the index and middle fingers. (d) It improves pinching power by augmenting the first two dorsal interosseous muscles. DISCUSSION
The rotation deformity of the index finger has been recognised and treated by several workers in this field. Transfer of extensor indicis proprius as a single unit to replace the first dorsal interosseous muscle appeared, at first, to be the obvious answer. Clinical experience, however, has been disappointing. Flexion and extension are often interfered with, and any variation in the insertion dorsally or volarly may result in extension or flexion contractures of the metacarpophalangeal joint. The transferred muscle is also much more powerful than the muscle it is replacing; this often results in fixed radial deviation of the index finger (Ellison, 1971). 138
The Hand--Vol. 8
No. 2
1976
Extensor Indicis
Proprius Trans[er
to Supplement Replacement Arthroplasty of the Rheumatoid Hand--S. L. Biddulph
. : . ~.~ ~ • dorsal expansion / . / ~ . ~ ~ extensor indlcis propriu ~ e x t e n s o r digitorum
I1~
"~ "
.~.~ ~¢([
E.I.P. isolated and split longitudinally (°l" a2)
split extensor indicis proprlus
f/~ ~ / J ~
~ ~
Dorsal expansion reconstituted
Fig. 2. Fig. 3. Fig. 4. Fig. 5.
Normal anatomy. The relationship of extensor indicis proprius to the common digital extensor is shown. The tendon of EIP is split as far back as possible before rerouting. Each slip is then inserted into the radial side of the dorsal capsule of the metacarpophalangeal joint of the index and middle fingers respectively. The radial collateral ligament can be utilised to reinforce the suture line, if the capsule is too attenuated. The dorsal hood should be accurately reconstituted. It should not be caught up in the tendon suture and must remain a separate, free structure.
Two other procedures have been employed with variable success. In Clayton's operation, the proximal end of the radial collateral ligament is transferred to the dorsum of the metacarpal neck (Clayton, 1971). In the procedure described by Swanson, the radial half of the volar plate is used to fashion an auxiliary ligament which is again inserted into the dorsum of the metacarpal neck (Swanson, 1972). These procedures have two inherent defects. Firstly, the ligaments are very short and the diameter of the metacarpal is small; consequently the effective leverage on the index finger is poor and the rotating power is comparatively ineffectual. Secondly, there is a tendency for the newly constructed ligament to stretch. By contrast, procedures employing an actively contracting musculotendinous unit do not run the same risk of stretching. The Hand---Vol. 8
No. 2
1976
139
Extensor Indicis
Proprius
Transfer to Supplement Replacement Arthroplasty of the Rheumatoid Hand--S. L. Biddulph
The normal pinching pattern in man is found to occur between the thumb and the index and middle fingers (Kaplan, 1965; Napier, 1956). The second and third digits should therefore be considered as a single unit when doing a tendon transfer. Furthermore, splitting the tendon of extensor indicis proprius effectively lessens the power of that muscle to a level more appropriate to its new function. In early cases of rheumatoid arthritis where there is commencing volar subluxation and ulnar deviation at the metacarpophalangeal joints, the transfer can be combined with a similar transfer using extensor digiti minimi to the ring and little fingers. The ulnar intrinsic tendons need to be released in addition. This operation has been performed on five hands with promising results. In two patients there was lack of full extension of the index and little fingers after the transfer. Plication of the tendons of extensor digitorum communis will obviate this problem to a large degree. REFERENCES
CALNAN, J. S. (1971) Artificial finger joints for rheumatoid arthritis. British Journal of Hospital Medicine, 5: 487491. CLAYTON, M. L. (1972) Personal Communication. ELLISON, M. R. KELLY, K. J., and FLATT, A. E. (1971) The Results of Surgical Synovectomy of the Digital Joints in Rheumatoid Disease. Journal of Bone and Joint Surgery, 53A: 1041-1082. FLATT, A. E. (1968) The care of the rheumatoid hand. 2nd Ed., St. Louis, The C. V. Mosby Company. KAPLAN, E. B. (1965) Functional and Surgical Anatomy of the Hand. 2nd Ed., Philadelphia and Montreal, J. B. Lippincott Company. NAPIER, J. R. (1956) The Prehensile Movements of the Human Hand. Journal of Bone and Joint Surgery, 38B: 902-913. NIEBAUER, J. J., SHAW, J. L. and DOREN, W. W. (1969) Silicone-Dacron Hinge Prosthesis. Design Evaluation and Application. International Workshop on Artificial Finger Joints. Annals of the Rheumatic Diseases, 28: Supp. 5, 56-58. SHAPIRO, J. S. (1968) The Etiology of Ulnar Drift. A New Factor. Journal of Bone and Joint Surgery, 50A: 634. SWANSON, A. B. (1968) Silicone Rubber Implants for Replacement of Arthritic or Destroyed Joints in the Hand. Surgical Clinics of North America, 48: 1113-1127. SWANSON, A. B. (1972) Flexible Implant Arthroplasty for Arthritic Finger Joints. Rationale, Technique and Results of Treatment. Journal of Bone and Joint Surgery, 54A: 432455. SWANSON, A. B. (1969) Finger Joint Replacement by Silicone Rubber Implants and the Concept of Implant Fixation by Encapsulation. International Workshop on Artificial Finger Joints. Annals of the Rheumatic Diseases, 28: Supp. 5, 47-55. TUBIANA, R. and HAKSTIAN, R. (1966) Normal and Pathological Ulnar Deviation of the Fingers. La Main Rhumatismale. Rheumatoid Hand. Paris, L'Expansion.
140
The Hand--Vol. 8
No. 2
1976
Trans/er to Supplement Replacement Arthroplasty o/ the Rheumatoid Hand--S. L. Biddulph
E X T E N S O R INDICIS PROPRIUS T R A N S F E R TO S U P P L E M E N T R E P L A C E M E N T A R T H R O P L A S T Y OF T H E R H E U M A T O I D H A N D S. L. BIDDULPH, Johannesburg SUMMARY A new procedure is described to, cope with the rotatiun deformity so often seen after replacement ar'throplasty of the destroyed metacarpophalangeal joints in rheumatoid arthritis. The same procedure, in combination with a similar transfer to the ring and little fingers, but using extensor digiti minimi as the motor, can be used as: a suspension procedure to stabilise the early unstable metacarpophalangeal joint. Thirty hands have been treated with the longest follow-up of two-and-a-half years; so far the results have been encouraging.
INTRODUCTION The management of metacarpophalangeal joint destruction in Rheumatoid Arthritis has been greatly improved by the development of suitable replacement prostheses (Calnan 1971, Flatt 1968, Niebauer 1969, Swanson 1968b). However, several problems still remain unsolved and Swanson (1972) has recently enumerated the complications encountered after replacement arthroplasty. Among these, rotation of the index finger and recurrence of ulnar drift is particularly disabling as it precludes effective use of the hand. With the fingers moving away from the thumb, there is marked weakening of pinching power. In those cases where there is gross involvement of the thumb, especially if arthrodeses have been carried out in this digit, the thumb may not be able to reach the displaced index and middle fingers at all. The present paper describes a procedure which successfully counteracts or corrects this disability.
Fig. 1. Typical rotation deformity of the index finger following replacement arthroplasty of the metacarpophalangeal joints in rheumatoid arthritis. S. L. Biddulph, F.C.S.(S.A.), F.R.C.S., University of Witwatersrand, Johannesburg, South Africa. The Hand--Vol. 8
No. 2
1976
137
Extensor lndicis Proprius
Transfer to Supplement Replacement Arthroplasty oJ the Rheumatoid Hand--S. L. Biddulph
CLINICAL F E A T U R E S The principal deformity of the index finger referred to here is pronation of the entire digit; this may be further aggravated by the presence of ulnar drift at the metacarpophalangeal joint. Often the middle finger is involved in a similar, though milder, fashion (Fig. 1). Several factors are believed to contribute to this deformity: weakness and volar displacement of the first dorsal interosseous muscle (Tubiana, 1966); tightness of the ulnar intrinsic muscles (Flatt, 1968); radial deviation of the metacarpal bones upon the wrist (Shapiro, 1968); and capsular stretching due to inadequate splintage of the metacarpophalangeal joints after replacement arthroplasty (Swanson, 1969). O P E R A T I V E CORRECTION
The procedure to be described was designed to correct or prevent pronationrotation of the index finger. Extensor indicis proprius is used as the motor (Fig. 2); this tendon is split in two longitudinally, one tail being used to supply the index finger and the other the middle finger (Fig. 3). Each tendon slip is inserted into the base of the proximal phalanx just dorsal to the radial collateral ligament. The latter structure may be used to reinforce the attachment to the bone and adjacent capsule (Fig. 4). If the soft tissues are deficient, insertion may be directly into bone via a small drill hole. Tension should be equal to that of the normal extensor indicis proprius. Care should be taken not to foul the dorsal expansion at the site of suture as this may result in subsequent swan-neck deformity of the digit (Fig. 5). Post-operatively the hand is immobilised in a voluminous pressure dressing for a week. At this stage mobilisation is commenced (Figs. 2, 3, 4, 5). RESULTS
The operation has been performed on thirty patients with satisfactory prevention of the rotation deformity. The longest follow-up is two-and-a-half years, the shortest is four months. Fifteen cases have been followed up for more than one year. The tendon transfer appears to have several effects: (a) It produces supination of the index and middle fingers. (b) It lessens the extensor lag usually seen after replacement arthroplasty. (c) It strengthens radial deviation of the index and middle fingers. (d) It improves pinching power by augmenting the first two dorsal interosseous muscles. DISCUSSION
The rotation deformity of the index finger has been recognised and treated by several workers in this field. Transfer of extensor indicis proprius as a single unit to replace the first dorsal interosseous muscle appeared, at first, to be the obvious answer. Clinical experience, however, has been disappointing. Flexion and extension are often interfered with, and any variation in the insertion dorsally or volarly may result in extension or flexion contractures of the metacarpophalangeal joint. The transferred muscle is also much more powerful than the muscle it is replacing; this often results in fixed radial deviation of the index finger (Ellison, 1971). 138
The Hand--Vol. 8
No. 2
1976
Extensor Indicis
Proprius Trans[er
to Supplement Replacement Arthroplasty of the Rheumatoid Hand--S. L. Biddulph
. : . ~.~ ~ • dorsal expansion / . / ~ . ~ ~ extensor indlcis propriu ~ e x t e n s o r digitorum
I1~
"~ "
.~.~ ~¢([
E.I.P. isolated and split longitudinally (°l" a2)
split extensor indicis proprlus
f/~ ~ / J ~
~ ~
Dorsal expansion reconstituted
Fig. 2. Fig. 3. Fig. 4. Fig. 5.
Normal anatomy. The relationship of extensor indicis proprius to the common digital extensor is shown. The tendon of EIP is split as far back as possible before rerouting. Each slip is then inserted into the radial side of the dorsal capsule of the metacarpophalangeal joint of the index and middle fingers respectively. The radial collateral ligament can be utilised to reinforce the suture line, if the capsule is too attenuated. The dorsal hood should be accurately reconstituted. It should not be caught up in the tendon suture and must remain a separate, free structure.
Two other procedures have been employed with variable success. In Clayton's operation, the proximal end of the radial collateral ligament is transferred to the dorsum of the metacarpal neck (Clayton, 1971). In the procedure described by Swanson, the radial half of the volar plate is used to fashion an auxiliary ligament which is again inserted into the dorsum of the metacarpal neck (Swanson, 1972). These procedures have two inherent defects. Firstly, the ligaments are very short and the diameter of the metacarpal is small; consequently the effective leverage on the index finger is poor and the rotating power is comparatively ineffectual. Secondly, there is a tendency for the newly constructed ligament to stretch. By contrast, procedures employing an actively contracting musculotendinous unit do not run the same risk of stretching. The Hand---Vol. 8
No. 2
1976
139
Extensor Indicis
Proprius
Transfer to Supplement Replacement Arthroplasty of the Rheumatoid Hand--S. L. Biddulph
The normal pinching pattern in man is found to occur between the thumb and the index and middle fingers (Kaplan, 1965; Napier, 1956). The second and third digits should therefore be considered as a single unit when doing a tendon transfer. Furthermore, splitting the tendon of extensor indicis proprius effectively lessens the power of that muscle to a level more appropriate to its new function. In early cases of rheumatoid arthritis where there is commencing volar subluxation and ulnar deviation at the metacarpophalangeal joints, the transfer can be combined with a similar transfer using extensor digiti minimi to the ring and little fingers. The ulnar intrinsic tendons need to be released in addition. This operation has been performed on five hands with promising results. In two patients there was lack of full extension of the index and little fingers after the transfer. Plication of the tendons of extensor digitorum communis will obviate this problem to a large degree. REFERENCES
CALNAN, J. S. (1971) Artificial finger joints for rheumatoid arthritis. British Journal of Hospital Medicine, 5: 487491. CLAYTON, M. L. (1972) Personal Communication. ELLISON, M. R. KELLY, K. J., and FLATT, A. E. (1971) The Results of Surgical Synovectomy of the Digital Joints in Rheumatoid Disease. Journal of Bone and Joint Surgery, 53A: 1041-1082. FLATT, A. E. (1968) The care of the rheumatoid hand. 2nd Ed., St. Louis, The C. V. Mosby Company. KAPLAN, E. B. (1965) Functional and Surgical Anatomy of the Hand. 2nd Ed., Philadelphia and Montreal, J. B. Lippincott Company. NAPIER, J. R. (1956) The Prehensile Movements of the Human Hand. Journal of Bone and Joint Surgery, 38B: 902-913. NIEBAUER, J. J., SHAW, J. L. and DOREN, W. W. (1969) Silicone-Dacron Hinge Prosthesis. Design Evaluation and Application. International Workshop on Artificial Finger Joints. Annals of the Rheumatic Diseases, 28: Supp. 5, 56-58. SHAPIRO, J. S. (1968) The Etiology of Ulnar Drift. A New Factor. Journal of Bone and Joint Surgery, 50A: 634. SWANSON, A. B. (1968) Silicone Rubber Implants for Replacement of Arthritic or Destroyed Joints in the Hand. Surgical Clinics of North America, 48: 1113-1127. SWANSON, A. B. (1972) Flexible Implant Arthroplasty for Arthritic Finger Joints. Rationale, Technique and Results of Treatment. Journal of Bone and Joint Surgery, 54A: 432455. SWANSON, A. B. (1969) Finger Joint Replacement by Silicone Rubber Implants and the Concept of Implant Fixation by Encapsulation. International Workshop on Artificial Finger Joints. Annals of the Rheumatic Diseases, 28: Supp. 5, 47-55. TUBIANA, R. and HAKSTIAN, R. (1966) Normal and Pathological Ulnar Deviation of the Fingers. La Main Rhumatismale. Rheumatoid Hand. Paris, L'Expansion.
140
The Hand--Vol. 8
No. 2
1976