TY - JOUR
AU - Murasawa, Akira
AB - Abstract Objective Digital joints affected by rheumatoid arthritis often have severe deformity and/or dislocation, and arthrodesis in a functional position is required. Methods Arthrodesis was performed using intraosseous wiring (modified Lister’s method) from January 2011 to December 2015, and we investigated the union rate, postoperative complications, and patient satisfaction with the operation at the final follow-up. The DASH score, grip power, and pinch power were also investigated before the operation and at the final follow-up. Results Arthrodesis was performed for 90 digital joints in 56 patients. Bone union was obtained in 85 of 89 joints (96%). Wire removal was needed due to subcutaneous protrusion in 20 joints and superficial infection in five joints. The mean preoperative DASH score of 50.5 improved to 45.2 at the final follow-up. The pulp pinch power of the index fingers through the little fingers changed significantly. In the questionnaire regarding the operated digit using a visual analogue scale (VAS, 0 [worst] to 100 [best]), the overall satisfaction was 70. Conclusion With this approach, we achieved painless stability as well as deformity correction. A restored prehensile pattern and improvement in the activities of daily life can thus be expected after surgery. Arthrodesis, deformity, digital joint, intraosseous wiring, rheumatoid arthritis Introduction Pharmacotherapy for rheumatoid arthritis (RA) improved dramatically after the appearance of biological disease-modifying anti-rheumatic drugs (bDMARDs) and new targeted synthetic disease-modifying anti-rheumatic drugs (tsDMARDs). However, at present, digital joint deformity is often seen not only in patients with poorly controlled RA but also in those with well-controlled RA. In cases of mild to moderate digital joint deformity, we try to perform conservative treatment using a splint or surgical treatment via synovectomy and soft-tissue balance restoration or implant arthroplasty. However, for digital joints with severe deformity and/or dislocation, arthrodesis in a functional position is required to restore the function of the hand by providing painless joints. Many reports on arthrodesis at the digital joints, including the distal interphalangeal (DIP) or the proximal interphalangeal (PIP) joints of the fingers and the interphalangeal (IP) or the metacarpophalangeal (MP) joints of the thumb, have been published. Most of them reported mixed conditions, such as cases of osteoarthritis, acute trauma, post-trauma, and rheumatoid arthritis. The materials of their arthrodesis including Kirschner wire (K-wire) and/or soft wire [1–9], compression screw [4,10–12], plate [13], and external fixator [14], and the usefulness and issues of these materials were described. In the digital joint of RA, the bone quality is generally very poor, so when choosing fixation materials, we must select the materials and methods depending on the bone quality at the operated site affected by long-lasting inflammation. The present study explored the effects of arthrodesis of a digital joint using intraosseous wiring (modified Lister’s method) [1] and the usefulness and issues of this method for RA patients alone. Methods A prospective cohort study was performed on the patient with RA, who were scheduled to perform arthrodesis of the digital joint from January 2011 to December 2015. The operation was indicated to the patients who had difficulty in picking up a small object due to painful instability and/or deformity at the deteriorated digital joint. Arthrodesis was performed using intraosseous wiring and we investigated the union rate at the time of the last follow-up via radiological assessment. Clinically, grip power and pinch power were measured just before the surgery at baseline and at the time of the last follow-up. Grip power and pinch power were measured using self-training exercise training machine with measuring function (Isoforce GT-300, OG Wellness Co., Okayama, Japan). Complications associated with this procedure, including infection, delayed wound healing, and wire removal, were investigated. A questionnaire inquiring about the postoperative condition of the operated digit was sent to the patients, and the patient’s reply was obtained using a visual analogue scale (VAS; 0 [worst] to 100 [best]). Operative technique For more than 30 years, intraosseous wiring has been performed on digital joints at our hospital according to the modified Lister’s method [1]. This method using a soft wire and a K-wire is used for fragile bones affected by RA (Figure 1). The operative procedures are as follows: Figure 1. Open in new tabDownload slide Preoperative and postoperative radiograph. Figure 1. Open in new tabDownload slide Preoperative and postoperative radiograph. Skin incision and exposure: A Y-shaped incision is placed at the extensor side of the thumb IP joint and the finger DIP joint. For the thumb MP joint and the finger PIP joint, a straight longitudinal median incision is placed on the extensor side. The extensor tendon is step-cut, and the capsule is opened. Synovectomy or the resection of fibrous tissue in the joint is performed. The articular surfaces of the two bones are exposed completely by releasing the collateral ligaments. Shaping a cancellous bony bed: A “Small Joint Reamer” (Acumed®; Hillsboro, OR) is used to create the articular surface in a cup and cone fashion using a 1.2-mm K-wire as a guide (Figure 2). By this procedure, it is possible to control the fixation angle. Depending on the fixation angle, additional cuts on the flexor side of the two bones are made using Luer forceps, if necessary. Figure 2. Open in new tabDownload slide Schema and picture of “Small Joint Reamer” (Acumed®). Figure 2. Open in new tabDownload slide Schema and picture of “Small Joint Reamer” (Acumed®). When there is a mutilating abnormality, which means a remarkable bone absorption and digital shortening, we graft a bone block at the operated site to restore the length of the digit. Wiring: A soft wire of 0.46 mm in diameter is introduced to the bone using a 21-G injection needle. Part of the injection needle is attached to the driver, and drilling is performed. A soft wire is passed through the bone (Scheker’s method) [15] (Figure 3). Two bones are manually fixed at an appropriate angle with moderate compression by an assistant, and the wire is fastened, taking care not to cut out of the bone. According to Shin et al., the ideal fixation angle is 40°, 45°, 50°, and 55° at the 2nd through 5th PIP joints, respectively [16]. The ideal fixation angle of the 2nd DIP joint is 0–5°, and that of the 3rd through 5th DIP joint is 5°. In the thumb, the ideal fixation angle of the IP joint is 15°, and that of the MP joint is 5–15°. This method makes it easy to pass the wire into the bone, as the hole is not lost when the wire is passed through, and the wire does not become caught in the bone. For small joints, such as the 5th DIP joint, a thin soft wire with a diameter of 0.32 mm is used. For large joints, like the thumb IP joint, a soft wire with a diameter of 0.5 mm and an 18-G injection needle are used. Figure 3. Open in new tabDownload slide Schema of Scheker’s method. Figure 3. Open in new tabDownload slide Schema of Scheker’s method. Additional fixation: A K-wire with a diameter of 1.2 mm is obliquely inserted to prevent rotation at the fused part. Bone wires are cut and buried under the skin. The extensor tendon is sutured, and the wound is closed with 5-0 nylon thread. A splint is applied to the operated joint until eight weeks postoperatively. Results Arthrodesis in our way was performed using intraosseous wiring for 90 digital joints in 56 patients. Both hands were operated in 4 patients. There were 50 female and six male patients, and the mean age (range) at the time of surgery was 63.6 (39–88) years. The mean disease duration was 21.5 (0.8–64) years, and the mean follow-up period was 3 (0.2–5.5) years. There were 31 IP joints and 5 MP joints of the thumb, 7 DIP joints, 9 proximal PIP joints of the index finger, 3 DIP joints and 13 PIP joints of the middle finger, 11 PIP joints of the ring finger, 10 PIP joints, and 1 MP joint of the little finger. Four cases with mutilating abnormality were combined with autologous iliac bone grafting. In 44 hands, other upper-extremity surgery was combined. MP joint arthroplasty using a Swanson implant was performed simultaneously on 32 joints in 22 hands. In addition, at the same operation, a Darrach procedure was performed in 17 hands, total fusion of the wrist using a rod in 6 hands, radio-lunate arthrodesis in 4 hands, ulnar stump stabilization using a half slip of the flexor carpi ulnaris (FCU) tendon in 3 hands, Clayton’s method in 2 hands, suspension arthroplasty by Thompson’s method at the trapeziometacarpal joint in 2 hands, Swanson implant arthroplasty at the MP joint other than the intraosseous wiring of the fingers in 13 hands, synovectomy of the digital joints in 7 hands, and capsulodesis at the 1st IP joint in 2 hands (Table 1). Table 1. Patients’ characteristics. Items Number of the patients 56 (Both hands were operated in 4 patients.) Number of the operated digital joints Thumb: 31 IP, 5 MP Index: 7 DIP, 9 PIP Middle: 3 DIP, 13 PIP Ring: 11 PIP Little:10 PIP, 1 MP Age (years) 63.6 (SD 10.5) Sex (males:females) 6:50 Duration of the disease (years) 21.5 (SD 10.8) Follow-up duration (years) 3 (SD 1.6) Number of joints/hands that underwent Swanson implant arthroplasty at the MP joint of the same finger 32 joints in 22 hands Number of hands that underwent other operations on the same hand and/or wrist 48 Items Number of the patients 56 (Both hands were operated in 4 patients.) Number of the operated digital joints Thumb: 31 IP, 5 MP Index: 7 DIP, 9 PIP Middle: 3 DIP, 13 PIP Ring: 11 PIP Little:10 PIP, 1 MP Age (years) 63.6 (SD 10.5) Sex (males:females) 6:50 Duration of the disease (years) 21.5 (SD 10.8) Follow-up duration (years) 3 (SD 1.6) Number of joints/hands that underwent Swanson implant arthroplasty at the MP joint of the same finger 32 joints in 22 hands Number of hands that underwent other operations on the same hand and/or wrist 48 IP: interphalangeal joint; MP: metacarpophalangeal joint; DIP: distal interphalangeal joint; PIP: proximal interphalangeal joint; SD: standard deviation. Open in new tab Table 1. Patients’ characteristics. Items Number of the patients 56 (Both hands were operated in 4 patients.) Number of the operated digital joints Thumb: 31 IP, 5 MP Index: 7 DIP, 9 PIP Middle: 3 DIP, 13 PIP Ring: 11 PIP Little:10 PIP, 1 MP Age (years) 63.6 (SD 10.5) Sex (males:females) 6:50 Duration of the disease (years) 21.5 (SD 10.8) Follow-up duration (years) 3 (SD 1.6) Number of joints/hands that underwent Swanson implant arthroplasty at the MP joint of the same finger 32 joints in 22 hands Number of hands that underwent other operations on the same hand and/or wrist 48 Items Number of the patients 56 (Both hands were operated in 4 patients.) Number of the operated digital joints Thumb: 31 IP, 5 MP Index: 7 DIP, 9 PIP Middle: 3 DIP, 13 PIP Ring: 11 PIP Little:10 PIP, 1 MP Age (years) 63.6 (SD 10.5) Sex (males:females) 6:50 Duration of the disease (years) 21.5 (SD 10.8) Follow-up duration (years) 3 (SD 1.6) Number of joints/hands that underwent Swanson implant arthroplasty at the MP joint of the same finger 32 joints in 22 hands Number of hands that underwent other operations on the same hand and/or wrist 48 IP: interphalangeal joint; MP: metacarpophalangeal joint; DIP: distal interphalangeal joint; PIP: proximal interphalangeal joint; SD: standard deviation. Open in new tab At the last follow-up, bone union was obtained in 85 of 89 joints to give a union rate of 96%, with one joint unable to be followed for more than three months. All 4 cases with an iliac bone grafting obtained complete bone union. Twenty-five joints (28%) required wire removal; nine joints required only K-wire removal, seven joints only soft wire removal, and nine both. The reason for wire removal was painful due to subcutaneous protrusion in 20 joints and superficial infection in five joints. Delayed wound healing occurred in three joints. After the appropriate procedures to those complications, preoperative digital joint pain disappeared completely in all patients. At the last follow-up, the DASH score significantly improved from 50.5 before surgery to 45.2 at the last follow-up (n = 60, p < .01). In the patients without combined procedures in the upper-extremity other than digital joint arthrodesis, the DASH score decreased non-significantly from 38.6 to 32.9 (n = 14, p = .11). A significant improvement was noted in the following item scores for DASH: “open a new glass jar or one with a very tight lid” (p = .02), “turn a key” (p < .01), “open a heavy door” (p = .02), “wash your back” (p = .02), “put on a shirt with buttons” (p < .01), “pain in your arm, shoulder or hand” (p = .04), “discomfort in the skin of your arm, shoulder or hand (pricking)” (p < .05), and “feel less capable, less confident and less useful because of your arm, shoulder or hand problem” (p = .02). The patients with digital joint arthrodesis only showed no significant improvements in any items. The mean grip power was 103.6 mmHg before surgery and 110.8 mmHg at the last follow-up (p = .24). The pulp pinch power of the 2nd through 5th fingers was 0.49 kgf before surgery and 0.70 kgf at the time of follow-up, showing significant improvement (p < .01) (Table 2). In the postoperative patients’ replies to the questionnaire regarding the operated digit using VAS, the overall satisfaction was 70, pain 87, ease of use 60, appearance 72, and ease of putting strength into the digit 61. Table 2. Clinical results. n Preoperative Postoperative p value (Wilcoxon signed-rank test) Grip power (mmHg) 56 103.6 110.8 0.24 Pinch power (kgf) 76 1.04 1.17 <0.01* Side pinch power (kgf) 29 1.89 1.85 0.97 Tip pinch power (kgf) 47 0.49 0.70 <0.01* DASH score　 60 50.5 45.2 <0.01* DASH score of hands that underwent only intraosseous wiring 14 38.6 32.9 0.11 n Preoperative Postoperative p value (Wilcoxon signed-rank test) Grip power (mmHg) 56 103.6 110.8 0.24 Pinch power (kgf) 76 1.04 1.17 <0.01* Side pinch power (kgf) 29 1.89 1.85 0.97 Tip pinch power (kgf) 47 0.49 0.70 <0.01* DASH score　 60 50.5 45.2 <0.01* DASH score of hands that underwent only intraosseous wiring 14 38.6 32.9 0.11 DASH score: disabilities of the Arm, Shoulder and Hand score. *p < .05. Open in new tab Table 2. Clinical results. n Preoperative Postoperative p value (Wilcoxon signed-rank test) Grip power (mmHg) 56 103.6 110.8 0.24 Pinch power (kgf) 76 1.04 1.17 <0.01* Side pinch power (kgf) 29 1.89 1.85 0.97 Tip pinch power (kgf) 47 0.49 0.70 <0.01* DASH score　 60 50.5 45.2 <0.01* DASH score of hands that underwent only intraosseous wiring 14 38.6 32.9 0.11 n Preoperative Postoperative p value (Wilcoxon signed-rank test) Grip power (mmHg) 56 103.6 110.8 0.24 Pinch power (kgf) 76 1.04 1.17 <0.01* Side pinch power (kgf) 29 1.89 1.85 0.97 Tip pinch power (kgf) 47 0.49 0.70 <0.01* DASH score　 60 50.5 45.2 <0.01* DASH score of hands that underwent only intraosseous wiring 14 38.6 32.9 0.11 DASH score: disabilities of the Arm, Shoulder and Hand score. *p < .05. Open in new tab Cases Case 1 A woman in her 40s had severe boutonnière deformity in the right ring and little fingers and difficulty in grasping large objects. Arthrodesis in a functional position was performed using intraosseous wiring. The PIP joint in the ring finger was fixed at 50° of flexion, and that in the little finger was fixed at 55° of flexion. A soft wire in the right ring finger had to be removed at four months after surgery due to skin ulcer, and in the little finger, a soft wire was also had to be removed at nine months due to skin irritation of a K-wire. An ulnar gutter splint was worn for 8 weeks after surgery and bony union was obtained at four months after surgery. The prehensile pattern improved, and she was able to grasp large objects. Case 2 A woman in her 50s whose job involved sewing complained of an inability to pick up a sewing machine needle due to a mutilating deformity in both thumbs. Both IP joints were dislocated radially, and severe shortening due to bone resorption had occurred (Figure 4). Arthrodesis at the IP joint using intraosseous wiring with a bone block graft was performed. A bone block was harvested from the iliac crest and interposed between the two bones. The IP joint was fixed at 15° of flexion (Figure 5). A splint for the IP joint was applied for 8 weeks. Complete bone union occurred at three months after surgery in the right thumb and at four months after surgery in the left thumb. At seven months after surgery, although there was no significant improvement in the grip power or side-pinch power, a large improvement was noted in the patient’s VAS. The preoperative appearance improved from 3 to 90 postoperatively. The ease of putting strength into the digit improved from 9 to 45, the ease of use improved from 7 to 85, and the overall satisfaction improved from 4 to 88. Figure 4. Open in new tabDownload slide Preoperative pictures and radiographs of Case 2. Figure 4. Open in new tabDownload slide Preoperative pictures and radiographs of Case 2. Figure 5. Open in new tabDownload slide Postoperative pictures and radiographs of Case 2. Figure 5. Open in new tabDownload slide Postoperative pictures and radiographs of Case 2. Discussion Digital joint arthrodesis in patients with RA restores the prehensile pattern by correcting the deformity and providing stability. Several methods for creating a cancellous bony bed and fixation have been reported. Each method has advantages, each with its and disadvantages. When making a cancellous bony bed, we use the cup and cone method. This method has benefits of relatively little shortening of the digit and a changeable fixation angle. If flat cuts are made at the joint surface, it is impossible to control the fixation angle, and shortening of the bone is required. There are several fixation materials available, including wires, screws, plates, and external fixators. The quality of bone affected by RA is usually poor and fragile, and these bones sometimes have a very thin cortex and no cancellous bone in the medullary canal. Therefore, special care is needed when selecting an adequate management method in order to reduce the risk of nonunion, pseudoarthrosis, and failure of fixation. When using only K-wire, it is impossible to apply compression force at the contact surfaces, and strong fixation for fragile bone is difficult to provide. Methods using only a soft wire carry a risk of cut-outs to the bone [2], and the fixation force is weak. Tension band wiring and using a cannulated screw or a headless compression screw (HCS) results in great stiffness [3]. In fact, the rate of union using an HCS is 85–100% [4,10–12], and that with tension band wiring is 92.8–100% [6–9]. However, tension band wiring has issues with pin protrusion and painful hardware, and Breyer reported that the rate of re-operation due to metal removal was 32.1% [7]. HCS is difficult to re-insert in order to correct the position or the screw length once installed. Furthermore, the bone of Japanese RA patients tends to be small and fragile, so tension band wiring and headless screw may be associated with intraoperative fracture and instability. In addition, the thickness of the distal phalanges is sometimes smaller than the trailing thread diameter of an HCS [17]. Therefore, the authors performed fixation by the combination of a K-wire and a soft wire. Wiring has advantages of being a low-cost and low-invasive method. In addition, compression can be applied safely to the contact surfaces by wiring, and rotation can be prevented by an obliquely inserted K-wire. Leibovic et al. reported that, on comparing fixation materials between RA and non-RA patients, the non-union rate at the PIP joint was the highest with K-wire fixation, followed by tension band wiring and Herbert screw fixation [4]. Stern et al. reported that the non-union rate at the DIP joint was similar among the three materials of crossover K-wires, the combination of a soft wire and a K-wire, and a Herbert screw [5]. Lister reported in 1978 that bone union using intraosseous wiring was obtained in 90.6% of the thumb MP or IP joints of RA and non-RA patients [1]. The authors’ method is a modified version of Lister’s method. One of the modifications involves the creation of a cancellous bony bed in the cup and cone shape, and a soft wire is passed through the bone using Scheker’s method. This modified method is relatively easy to perform, and the bone union rate is high. However, we must be careful not to allow the stump of the K-wire or soft wire to protrude and take care to push them under the skin at the time of surgery. Thus far, there have been few reports describing the postoperative functions and the patient-reported outcomes after digital joint arthrodesis. We also investigated the pre- and post-operative DASH score. Although intraosseous wiring may contribute to the DASH score, such an evaluation is difficult because there are a small number of single operations, and we must evaluate these factors in combination. Among other items in this study, we showed that the hand function improved, and the patient satisfaction was high thanks to the painless postoperative stability at the digital joint. Conflict of interest None. References Lister G Intraosseous wiring of the digital skeleton . J Hand Surg Am . 1978 ; 3 ( 5 ): 427 – 35 . Google Scholar Crossref Search ADS PubMed WorldCat Kovach JC , Werner FW, Palmer AK, Greenkey S, Murphy DJ Biomechanical analysis of internal fixation techniques for proximal interphalangeal joint arthrodesis . J Hand Surg Am . 1986 ; 11 ( 4 ): 562 – 6 . Google Scholar Crossref Search ADS PubMed WorldCat Capo JT , Melamed E, Shamian B, Hadley SR, Ng Lai W, Gerszberg K, et al. 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Google Scholar Crossref Search ADS WorldCat © 2020 Japan College of Rheumatology This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model)
TI - Arthrodesis of the digital joint using intraosseous wiring in patients with rheumatoid arthritis
JF - Modern Rheumatology
DO - 10.1080/14397595.2020.1726607
DA - 2021-01-02
UR - https://www.deepdyve.com/lp/oxford-university-press/arthrodesis-of-the-digital-joint-using-intraosseous-wiring-in-patients-VGa2ExuGOV
SP - 114
EP - 118
VL - 31
IS - 1
DP - DeepDyve
ER -