Reconstruction of Post Burn Palmar Web Contractures: A Surgical Approach
SAMY AHMAD SHEHAB
EL-DIN, M.D.; AHMAD BAHAA EL-DIN, M.D.; EL-SAYED EL-SHAFEEY, M.D. and OSAMA MOHAMAD
Our study included 31 patients with postburn palmar web contractures. The patients were admitted to the Plastie, Reconstructive and Burn Unit, Mansoura University Hospitals, Egypt and King Fahd Central Hospital, Gizan, K.S.A., from November 1996 tlirou..Ii November 1998. The palmar web contractures were c i assified into 3 types: type 1: Without flexion or deformity at MI? joints, type II: With mild flexion deformity at MP joints and type III: With moderate and severe flexion deformity at MP joints. The surgical procedures applied were five-flap Y-V advancement and Z-plasty for type 1, dorsal flap with lateral digital extensions for type II and dorsal rectangular flap and single triangular palmar flap with full - thickness skin graft for type III. The results were satisfactory and the complications were inininial.
A contact burn on the distal palm to the fingers causes a characteristic contracture on the palmar surface of the web, with expansion of the dorsal web skin, which is otherwise normal. Various methods have been described to correct these contractures: the interdigital butterfly flap [11 the square flap [21, the Mustarde' multiple flap [31, the "SeagulP flap [4,51, a variety of Zplasty procedures [61, flap frorn the lateral surface of a finger [7401 and the lateral-volar flaps [111. In this article, we present our surgical ap~ proach in the reconstruction of post-burn palmar web contractures.
PATIENTS AND METHODS
This study included 31 patients (22 males, 9females) with post-bum palmar web contraclures. These patients were admitted to the Plastic, Reconstructive and Burn Unit in both Mansoura University Hospital, Egypt and King Fabd Central Hospital, Gizan, K.S.A. from November 1996 through November 1998. All patients had photographs taken before and after surgery. Goniometric range-of-motion measurements were obtained pre-operatively and at each post-operative clinic visit. The joints of the affected fingers were evaluated radiographically. The mean age was 15.2 years with a range of 5-42 years.The normal metacarpophalangeal (NIP) joint flexion: range-of-motion is from 0-90 degrees. The degree of flexion deformity at MP joints had been classified into: mild (0-45'), moderate (45'-90') and severe (90' or more) [121. The whole group was subdivided into 3 subgroups. Group 1: Palmar web contractures without flexion deformity at MP joints. This included 11 patients (8 males and 3 females). The mean age was 15.2 years with a range of 5-42 years. Group II: Palmar web contractures with mild flexion deformity at MP joints. This comprised 12 patients (8 males and 4 females). The mean age was 18 years with a range of 6-40 years. Group Ill: Palmar web contractures with moderate flexion deformity at MP joints. This included 8 patients (6 males and 2 females). The mean age was 10.8 years with a range of 5-15 years.
I- Five-flap Y-V advancement and Z-plasty(Fig. 1) :
The central flap (c) is advanced in a Y-V fashion. The flaps of the two Z-plasties on each side of the central flaps are transposed. This technique is suitable for palmar web contractures without flexion contracture of the finger at the level of the MP joints.
II- Dorsal flap with lateral digital extensions(Fig. 2) :
This technique is suitable for palmar web contractures associated with mild flexion contractures of the fingers at the level of the MP joints.A proximally based flap, with extensions to the lateral side of the adjacent fingers is outlined (Figs. 2-A, 2-13). The tip of each lateral digital flap is marked on the mid-lateral line over the proximal interphalangeal (PIP) joints. The length of the dorsal flap from its base to the site where the lateral digital extensions originate is planned so the flap will reach the level of the proximal flexion creases of the fingers. A palmar transverse line is marked at the level of the proximal flexion creases of the fingers (Fig. 2). The point where this line is over the lateral border of one of the fingers, with the fingers abducted, is marked. A line is then drawn obliquely from this point across the web to the palmar edge of the lateral flap of the other fingers. In this way, two triangular flaps on the palmar surface of the web are designed .Skin incisions are first made on the palmar surface and the two triangular flaps are raised. The flexion contractures of the fingers are released by this incision. Next, the lateral digital flaps are elevated off the paratenon of the extensor expansion and the dissection continued proximally with elevation of the dorsal flap. After all contracted tissues have been released, the lateral digital flaps are transposed to the palmar surface. The lateral flap donor sites of the fingers are each closed with a triangular flap. Subcutaneous undermining on the dorsal aspect of each finger is necessary for this closure and sometimes deflatting is necessary .
III- Dorsal rectangular flap combined with a single palmar triangular flap and fullthickness skin graft (Fig. 3) :
This technique is suitable for palmar web contractures associated with moderate or severe flexion contractures of the fingers at the level of the MPioints .
Forty procedures had been performed to release post-bum palmar web contractures in 31 patients: Group 1 comprised 11 patients reconstructed by five-flap Y-V advancement and Zplasty procedure (17 procedures). Group 11 included 12 patients reconstructed by dorsal flap with lateral digital extensions procedure (15 procedures) (Fig. 4). Eight patients in group IIIwere reconstructed by dorsal rectangular flap combined with single palmar triangular flap and full-thickness skin grafts (8procedures). All flaps survived even when raised in scar tissue or areas previously grafted. Satisfactory release was obtained in all cases and none of the patients has required a second interference, with no recurrence of contracture. The average time of hospitalization was 10 days. The maximum period of follow up had been 6 months.
Burns can result in contractures of the dorsal or palmar areas of the webs between the fingers. Direct attention to the spacing between digits during the acute injury treatment phase can prevent web space contracture. Since maintenance of the hand in the "safe" position, with the MP joints flexed, places the digits in marked adduction, exercises must be prescribed which maintain abduction and spreading in addition to flexion and extension [16,17]. Larson suggested that pressure garments can remodel immature contracture and overcome the need for surgery . For mature contractures, sur~ gery seeks to accomplish one of three goals: break line and add length to a straight-line contracture; recreate the web space commissure by use of local flaps and add skin from outside the local area for severely scarred web spaces .Burn syndactly can be corrected using a variety of methods. While many authors have suggested that tissue deficiency is the major problem. Krizek et al., reported that most cases of burn syndactiy could be successfully treated with local flaps. Extreme webbing with extension to the proximal interphalangeal joint did, however, often require the addition of tissue for successful treatment. The simplest approach to lengthen a straight-line contracture Is a Zplasty. Z-plasties placed side-to-side, in tandem and employing various angles, such as four-flap and five-flap Z-plastles are used when the webbing covers a longer distance. On occasion, skin grafts are added in combination with local flaps with the local flap preferentially placed on the dominant side and the skin graft on the nondominant side [6,16].Shaw et al., described a double-opposing Zplasty, a so-called interdigital butterfly flap . Hyakusoku and Fumiiri described a square flap combined with two triangular flaps elevated distal to the square flap; the square flap is advanced to correct a scar contracture and the triangular flaps are transposed either side of the square flap . Chapman et al., reported the use of the Mustarde' multiple flap technique for congenital syndactly and burn contractures of fingers . Smith and Harrison used a flap on the dorsal surface of a syndactly web, with distal extensions of the flap onto the dorsal surfaces of the adjacent fingers, the "seagull" flap, for post-burn syndactly . Multiple Seagull flaps have been used for digital contractures after electrical burns and congenital syndactly . The donor sites on the dorsum of each finger require a skin graft.An alternative approach has been the use of a flap from the lateral surface of a finger with skin grafts of the donor sites [7-10]. Other variations of lateral flaps are the lateral-volar flaps for burn syndactly . Marumo et al., have described a dorsal rectangular flap combined with a single palmar triangular flap for release of syndactly; this technique required full-thickness skin grafts in some areas of the fingers .Kojima et al., have described a dorsal flap with lateral digital extensions for palmar web contractures [141. The technique does not require skin grafts for flap donor sites. The blood supply is based on the dorsal metacarpal artery and dorsal branches of the main digital arteries [20,21]. The lateral digital flaps have to be elevated carefully off the extensor expansion and fat should be left at the base of the common dorsal flap. In order to close the donor sites of the lateral digital flaps, the skin on the dorsum of the donor fingers has to be undermined. The technique is suitable for palmar web contractures associated with mild flexion contracture of the fingers at the level of the MP joints. It can be used for multiple web contractures. It may be possible to use it for congenital syndactly up to the level of the proximal interphalangeal joints.
double-opposing-plasty. J. Bone Joint Surg., 55A: 1677, 1973.
Endo T., Kojima T. and Hiras Y.: Vascular anatomy of the finger dorsum and a new idea for coverage of the finger pulp defect that restores sensation. J. Hand Surg., 17A: 927, 1992.