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Joint preserving surgery for rheumatoid forefoot deformities improves pain and corrects deformity at midterm follow-up
The Foot 22 (2012) 81–84
Contents lists available at SciVerse ScienceDirect
The Foot journal homepage: www.elsevier.com/locate/foot
Joint preserving surgery for rheumatoid forefoot deformities improves pain and corrects deformity at midterm follow-up Mainudden Bhavikatti ∗ , Mathew David Sewell, Nawfal Al-Hadithy, Sarfraz Awan, M.A. Bawarish Department of Orthopaedic Surgery, Darlington Memorial Hospital, Darlington, UK
a r t i c l e
i n f o
Article history: Received 16 October 2011 Received in revised form 13 December 2011 Accepted 26 December 2011 Keywords: Forefoot Rheumatoid Joint preserving
a b s t r a c t Background: Rheumatoid arthritis is a chronic autoimmune disorder that commonly affects the metatarsophalangeal (MTP) joints. Conventional surgical treatment involves joint-sacrificing surgery to relieve pain and correct deformity. Objectives: We retrospectively reviewed 49 patients with rheumatoid forefoot deformities who underwent 66 joint preserving procedures with Scarf osteotomy of the first metatarsal and Weil’s shortening osteotomy of the lesser metatarsals. Method: There were 5 males and 44 females with mean age 56.1 years and mean follow-up 51 months. All patients were evaluated clinically and radiologically with hallux valgus angle (HVA) and inter-metatarsal angle (IMA). Results: Mean AOFAS score improved from 39.8 preoperatively to 88.7 at final follow-up. Subjectively patients reported their outcome as excellent in 49 feet (74%), good in 9 feet, fair in 7 feet and poor in 1 foot. Five feet had residual stiffness and 11 residual pain. Mean HVA and IMA decreased from 32◦ to 14◦ and from 15◦ to 11◦ respectively. Conclusion: In intermediate to severe stages of the disease, joint preserving surgery by Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals may be performed as an alternative to joint-sacrificing procedures and should be considered as a complement to the various surgical treatments of the rheumatoid forefoot. © 2011 Elsevier Ltd. All rights reserved.
1. Introduction Rheumatoid arthritis (RA) is a chronic autoimmune disorder that affects the metatarsophalangeal (MTP) joints first in 17% of patients [1]. Symptomatic rheumatoid forefoot deformities may affect as many as 89% of patients with RA [1]. The destructive synovitis results in joint erosion, destructive arthritis, loss of capsular and collateral ligament integrity leading to pain and deformity. Typical deformities include hallux valgus, hammer toe deformities of the lesser toes and subluxation or dislocation of MTP joints. Whilst there are various less commonly performed operative procedures described for the treatment of rheumatoid forefoot deformity including excision arthroplasty, silicone arthroplasty and amputation [2–9], the current gold standard, and most commonly performed treatment involves arthrodesis of the first MTP joint with resection arthroplasty of the lesser metatarsal heads [2]. There have been few studies on joint preserving surgery for rheumatoid forefoot deformities and it has been previously stated
∗ Corresponding author. E-mail address: [email protected] (M. Bhavikatti). 0958-2592/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.foot.2011.12.002
that patients will have poor outcomes in surgical procedures that do not involve fusion of the hallux MTP joint due to recurrent deformities [3,4,10]. Scarf osteotomy of the first metatarsal with a harmonised shortening of the lesser metatarsals by Weil osteotomy has been suggested to result in good correction of forefoot deformities at midterm follow-up [5]. The Scarf osteotomy allows for a wide range of fragment displacement and has inherent stability with relatively simple internal fixation [5]. The Weil osteotomy is an oblique shortening osteotomy which has been recommended for the treatment of the subluxed or dislocated joint and correction of lesser toe deformities by reducing the soft tissue tension [11]. Advantages of joint preserving surgery include maintaining available mobility of the first MTP joint which helps compensate for fixed deformity of the mid and hind-foot, as well as preserving the ability to perform revision surgery in future should progressive joint destruction occur. One study of 30 patients (39 feet) who underwent combined first tarsometatarsal fusion and shortening oblique osteotomies of the second to fourth metatarsals reported improvements in foot function at mean follow-up of 36 months [3]. Fourteen patients had persistent forefoot stiffness and four required removal of hardware. Thordarson et al. reported on joint salvage in 15 feet affected by RA and concluded that patients will
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Fig. 1. Preoperative standing anteroposterior (A) and oblique (B) foot radiographs of a 60-year-old patient with RA, hallux valgus deformity, hammer toes and painful lesser toe callosities. One year postoperative standing anteroposterior (C) and lateral (D) foot radiographs following first ray Scarf osteotomy and second to fourth ray Weil osteotomies. The patient had a stable first ray with correction of lesser toe deformities and complete resolution of pain.
M. Bhavikatti et al. / The Foot 22 (2012) 81–84
have poor surgical outcomes in those that do not involve fusion of the hallux MTP joint [10]. Concerns regarding persistent pain, stiffness and recurrence with this treatment strategy remain [3,10]. The aim of this study was to report the clinical and radiological results of joint preserving surgery for the first MTP joint and lesser toes in 49 patients (66 feet) with rheumatoid forefoot deformities. We hypothesised that joint preserving surgery of the first MTP joint and lesser toes in patients with RA would correct deformity and improve pain at midterm follow-up. 2. Patients and methods Between January 2000 and December 2005, 49 consecutive patients with rheumatoid forefoot deformities (66 feet) underwent Scarf osteotomy of the first metatarsal and/or Weil osteotomy of the lesser metatarsals. There were 44 females and 5 males with a mean age of 56.1 years (17–70 years) and mean follow-up of 51 months (40–65 months) (Fig. 1). Patients were diagnosed with their rheumatoid disease at a mean of 10.5 years (5–20 years) preoperatively. Seventeen patients underwent bilateral procedures. Indications for surgery were disabling foot pain affecting function with painful hallux valgus deformity, prominent lesser toe metatarsal heads and/or hammer toe deformity with callosities. All patients had failed to respond to conservative treatment (insoles and footwear modification). Contraindications to joint salvage were active rheumatoid forefoot synovitis and severe erosive arthritic change in the MTP joints. Fifty-nine feet underwent Scarf osteotomy for hallux valgus with an additional Weil osteotomy performed in 39 feet for lesser toe deformity and pain. Seven feet (three bilateral) underwent isolated Weil osteotomy for lesser toe deformities. The total number of Weil osteotomies performed was 108. Twenty-four feet required an additional fusion of the lesser toe proximal interphalangeal joint for fixed lesser toe hammer toe deformity. Data were collected retrospectively from medical records, clinic reviews and radiographs. The preoperative and postoperative radiographs were analysed independently by the first author. Severity of arthritis in the first MTP joint was categorised into four grades (1–4) as described by Coughlin [2]. Preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) forefoot scores [12] were used to assess clinical outcome. The AOFAS produces a score out of 100 which includes assessment of pain, level of activity, deformity and motion. A subjective scoring system where patients graded their perceived outcomes as either poor, fair, good or excellent was also used, as described by Coughlin [2]. 2.1. Surgical technique The main principle is joint preservation by shortening osteotomy of all symptomatic metatarsals performed at the level of the MTP joints and metatarsal heads. All operations were performed supine with a thigh tourniquet under spinal or general anaesthesia by the senior author. A lateral soft tissue release and excision of prominent osteophytes is performed through a dorsomedial approach to the first MTP joint. Scarf osteotomy was performed on the first ray and internally fixed with two cannulated interfragmentary screws in 59 feet. The Scarf osteotomy is primarily a shortening and lateral translational osteotomy [11]. In this study the average shortening of the first ray was 6 mm (4–12 mm). Medial capsulorrhaphy aids restoration of MTP joint congruity. The four lesser MTP joints are exposed through two dorsal longitudinal incisions centred over the second and fourth inter-metatarsal spaces. When the first metatarsal is shortened by 5 mm or more then Weil osteotomy of the lesser metatarsals is routinely performed to decompress the first MTP joint. Tight soft
83
tissues are released. Weil osteotomy was performed in 46 feet to correct dislocation or subluxation of lesser MTP joints associated with painful callus. In this study the average shortening of the lateral rays was 8 mm. The oblique osteotomy is internally fixed with a single twist-off screw unless it was felt that the bone was too osteopenic to provide adequate stability. The normal anatomical inclination of lesser metatarsal should be restored with equal length of the first and second metatarsals following the rules of Tanaka et al. [13]. An additional lesser toe proximal interphalangeal joint fusion with Kirschner wire fixation was performed in 24 feet to correct persistent fixed flexion deformities. Postoperatively two intravenous doses of cefuroxime were administered and Kirschner wires removed at 4 weeks. Patients were mobilised in heel weightbearing shoes for 6 weeks. 3. Results 3.1. Clinical results Subjectively patients reported their outcome as excellent in 49 feet (74%), good in 9 feet (13.5%), fair in 7 feet (10.5%) and poor in 1 foot (1%). Postoperatively persistent pain was reported in 11 feet, stiffness in 5 feet and recurrence of hallux valgus deformity in 3 feet. Mean preoperative AOFAS score increased from a mean of 39.8 (18–56) preoperatively to 88.7 (48–92) at final follow-up. Preoperatively severe pain was present in 44 feet (67%), moderate pain in 19 feet (29%) and mild pain in 3 feet (4.5%). Postoperatively no pain was reported in 55 feet (83%), mild pain in 4 feet (6%) and moderate pain in 7 feet (10.5%). Preoperatively painful callus under the metatarsal heads was reported in 38 feet. No patients reported painful callus postoperatively. 3.2. Radiographic results Preoperative radiographs showing arthritic changes in the first MTP joint were mild in 19 feet, moderate in 42 feet and severe in 5 feet. Twenty-one lesser toe MTP joints were dislocated and 87 were subluxed. Mean hallux valgus angle (HVA) decreased from a preoperative mean of 32◦ (23–59◦ ) to 14◦ (5–28◦ ) at final followup. Inter-metatarsal angle (IMA) decreased from a preoperative mean of 15◦ (9–21◦ ) to 11◦ (5–14◦ ) at final follow-up. 3.3. Complications One patient developed a superficial wound infection requiring oral antibiotics. Persistent pain was reported in 11 feet, stiffness in 5 feet, recurrence of hallux valgus deformity in 3 feet and recurrence of lesser toe deformity in 5 feet. All three patients who had symptomatic recurrence (HVA > 18◦ and IMA > 11◦ ) of hallux valgus deformity had a preoperative HVA of >45◦ . Active synovitis was the cause of recurrent pain in two patients, failure to restore the natural metatarsal curve with inadequate shortening of the first metatarsal was thought to be the cause of recurrent pain in a further two patients and significant arthritic change in the MTP joints was the cause of continuing pain in the remaining patients. All patients with persistent pain did not request further surgery and were managed non-operatively with orthopaedic footwear and analgesia. One patient had numbness in a lesser toe which resolved after 3 weeks. There were no cases of non-union or osteonecrosis or requirement for removal of hardware. 4. Discussion There have been several different operative procedures described for the treatment of rheumatoid forefoot deformity
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including excision arthroplasty, silicone arthroplasty and amputation [2–9]; however the most commonly performed treatment involves arthrodesis of the first MTP joint with resection arthroplasty of the lesser metatarsal heads [2,14]. Coughlin performed a retrospective review of 32 patients with RA forefoot deformities who underwent arthrodesis of the first MTP joint with resection arthroplasty of the lesser metatarsal heads. Sustained deformity correction and good clinical outcomes (mean AOFAS score 69) were reported at mean follow-up of 108 months; however mild to moderate pain was still present in 62% of feet and 68% still had some degree of limitation clinically. The theoretical benefits of joint salvage in the rheumatoid forefoot are maintenance of first MTP joint mobility which aids toe off during the gait cycle and helps compensate for fixed deformity in the mid and hind-foot. Thordarson et al. reported the results of joint salvage in 15 feet affected by RA and concluded that patients will have poor outcomes in surgical procedures that do not involve fusion of the hallux MTP joint [10]. Graham reported four patients with RA who were treated with resection arthroplasty of the second to fifth metatarsal heads without first MTP joint surgery [14]. Three patients required subsequent first MTP joint fusion for persistent pain and recurrent deformity and the author advised against joint salvage in the rheumatoid forefoot. However recently this has been questioned. Barouk and Barouk reported preliminary results of joint salvage surgery in 34 patients with RA forefoot deformities who underwent Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals [9]. Clinical outcome was not assessed; however 86% of lateral metatarsal heads were preserved and sustained hallux valgus deformity correction was present in 92% of operated feet. The aim of joint preserving surgery in rheumatoid forefoot deformities is not to create a normal foot but to correct gross deformity, alleviate pain, and improve function. We believe the key to a successful outcome is achieving a stable realignment of the first ray to increase weight-bearing along the medial column of the foot, minimise stress on the lateral metatarsal heads and protect the relocated plantar fat pad. This is achieved by shortening all the metatarsals following the rules of Tanaka et al. [13] and laterally translating the first metatarsal with a Scarf osteotomy [9]. This provides longitudinal decompression of the first MTP joint and reduces deforming forces on the correction. In the present series the mean HVA decreased from 32◦ preoperatively to 14◦ at final follow-up which is an acceptable correction, compared with other studies investigating the surgical treatment of hallux valgus [3,4,8]. Berg et al. [4] reviewed 17 patients with RA forefoot deformities who underwent Scarf and Weil osteotomies. At 65 months follow-up, the majority of patients (79%) were satisfied with their result and mean HVA decreased from 41◦ to 23◦ . The main complications we observed with this treatment strategy were persistent pain in 11 feet, stiffness in 5 feet and recurrence of hallux valgus deformity in 3 feet. None of the 11 patients requested further surgery due to their symptoms being too mild to warrant further surgery. The three patients who had recurrence of deformity had severe hallux valgus deformity (>45◦ ) preoperatively which is likely to have predisposed to this. We believe active synovitis was the cause of recurrent pain in two patients, failure to restore the natural metatarsal curve with inadequate shortening of the first metatarsal was the cause of recurrent pain in a further two patients and significant arthritic change in the MTP joints was the cause of continuing pain in the remaining patients. This study suggests joint preserving surgery is effective in moderate to severely damaged MTP joints; however the study did not include patients with extensive joint damage and it is not clear whether
this subgroup of patients should be considered for joint sparing or joint-sacrificing surgery. There are limitations to this study including selection, measurement and interviewer bias. Although the AOFAS is a frequently used scoring system that allows comparison with other studies, SooHoo et al. [15] demonstrated poor correlation between the AOFAS and Medial Outcomes Study Short Form-36 (SF-36) and suggested that the AOFAS may have poor construct validity. However Baumhauer et al. [16] reported good correlation between the AOFAS and validated Foot Function Index [17] in a subgroup analysis of rheumatoid patients. Patients in the current study had less pain and better functional outcome than with the traditional treatment of metatarsal head resection and first MTP joint fusion [2]. In severe hallux valgus deformity with radiological destruction of the first MTP joint we recommend a primary fusion. Medical management of RA is improving and this study has shown that in intermediate to severe stages of the disease, joint preserving surgery by Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals may be performed as an alternative to joint-sacrificing procedures and should be considered as a complement to the various surgical treatments of the rheumatoid forefoot. Conflict of interest None. References [1] Vainio K. Rheumatoid foot. Clinical study with pathological and roentgenological comments. Ann Chir Gynaecol Fenniae (Suppl) 1956;45:1–107. [2] Coughlin MJ. Rheumatoid forefoot reconstruction. A long-term follow up study. J Bone Joint Surg Am 2000;82:322–41. [3] Niki H, Hirano T, Okada H, Beppu M. Combination joint-preserving surgery for forefoot deformity in patients with rheumatoid arthritis. J Bone Joint Surg Br 2010;92:380–6. [4] Berg RP, Kelder W, Olsthoorn PRM, Poll RG. Scarf and Weil osteotomies for correction of rheumatoid forefoot deformities: a review of 20 cases. Foot Ankle Surg 2007;13:35–40. [5] Barouk LS. Scarf osteotomy for hallux valgus correction. Local anatomy, surgical technique, and combination with other forefoot procedures. Foot Ankle Clin 2000;5:525–58. [6] Flint M, Sweetnam R. Amputation of all toes. A review of forty-seven amputations. J Bone Joint Surg Br 1960;42:90–6. [7] Moeckel BH, Sculco TP, Alexiades MM, Dossick PH, Inglis AE, Ranawat CS. The double-stemmed silicone-rubber implant for rheumatoid arthritis of the first metatarsophalangeal joint. Long-term results. J Bone Joint Surg Am 1992;74(4):564–70. [8] Vahvanen V, Piirainen H, Kettunen P. Resection arthroplasty of the metatarsophalangeal joints in rheumatoid arthritis. A follow-up study of 100 patients. Scand J Rheumatol 1980;9:257–65. [9] Barouk LS, Barouk P. Joint-preserving surgery in rheumatoid forefoot: preliminary study with more than two year follow-up. Foot Ankle Clin North Am 2007;12:435–54. [10] Thordarson DB, Aval S, Krieger L. Failure of hallux MP preservation surgery for rheumatoid arthritis. Foot Ankle Int 2002;23:486–90. [11] Weil LS. Scarf osteotomy for correction of hallux valgus. Historical perspective, surgical technique, and results. Foot Ankle Clin 2000;5:559–80. [12] Kitaoka HB, Alexander IJ, Adelaar RS, Nunley JA, Myerson MS, Sanders M. Clinical rating systems for the ankle hindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 1994;15:349–53. [13] Tanaka Y, Takakura Y, Kumai T, Samoto N, Tamai S. Radiographic analysis of hallux valgus. A two-dimensional coordinate system. J Bone Joint Surg Am 1995;77(2):205–13. [14] Graham CE. Rheumatoid forefoot metatarsal head resection without first metatarsophalangeal arthrodesis. Foot Ankle Int 1994;15:689–90. [15] SooHoo NF, Shuler M, Fleming LL. Evaluation of the validity of AODAS Clinical Rating Systems by correlation to the SF-36. Foot Ankle Int 2003;24(January (1)):50–5. [16] Baumhauer JF, Nawoczenski DA, DiGiovanni BF, Wilding GE. Reliability and validity of the American Orthopaedic Foot and Ankle Society Clinical Rating Scale: a pilot study for the hallux and lesser toe. Foot Ankle Int 2006;27(December (12)):1014–9. [17] Budiman-Mak E, Conrad KJ, Roach KE. The Foot Function Index: a measure of foot pain and disability. J Clin Epidemiol 1991;44(6):561–70.
Contents lists available at SciVerse ScienceDirect
The Foot journal homepage: www.elsevier.com/locate/foot
Joint preserving surgery for rheumatoid forefoot deformities improves pain and corrects deformity at midterm follow-up Mainudden Bhavikatti ∗ , Mathew David Sewell, Nawfal Al-Hadithy, Sarfraz Awan, M.A. Bawarish Department of Orthopaedic Surgery, Darlington Memorial Hospital, Darlington, UK
a r t i c l e
i n f o
Article history: Received 16 October 2011 Received in revised form 13 December 2011 Accepted 26 December 2011 Keywords: Forefoot Rheumatoid Joint preserving
a b s t r a c t Background: Rheumatoid arthritis is a chronic autoimmune disorder that commonly affects the metatarsophalangeal (MTP) joints. Conventional surgical treatment involves joint-sacrificing surgery to relieve pain and correct deformity. Objectives: We retrospectively reviewed 49 patients with rheumatoid forefoot deformities who underwent 66 joint preserving procedures with Scarf osteotomy of the first metatarsal and Weil’s shortening osteotomy of the lesser metatarsals. Method: There were 5 males and 44 females with mean age 56.1 years and mean follow-up 51 months. All patients were evaluated clinically and radiologically with hallux valgus angle (HVA) and inter-metatarsal angle (IMA). Results: Mean AOFAS score improved from 39.8 preoperatively to 88.7 at final follow-up. Subjectively patients reported their outcome as excellent in 49 feet (74%), good in 9 feet, fair in 7 feet and poor in 1 foot. Five feet had residual stiffness and 11 residual pain. Mean HVA and IMA decreased from 32◦ to 14◦ and from 15◦ to 11◦ respectively. Conclusion: In intermediate to severe stages of the disease, joint preserving surgery by Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals may be performed as an alternative to joint-sacrificing procedures and should be considered as a complement to the various surgical treatments of the rheumatoid forefoot. © 2011 Elsevier Ltd. All rights reserved.
1. Introduction Rheumatoid arthritis (RA) is a chronic autoimmune disorder that affects the metatarsophalangeal (MTP) joints first in 17% of patients [1]. Symptomatic rheumatoid forefoot deformities may affect as many as 89% of patients with RA [1]. The destructive synovitis results in joint erosion, destructive arthritis, loss of capsular and collateral ligament integrity leading to pain and deformity. Typical deformities include hallux valgus, hammer toe deformities of the lesser toes and subluxation or dislocation of MTP joints. Whilst there are various less commonly performed operative procedures described for the treatment of rheumatoid forefoot deformity including excision arthroplasty, silicone arthroplasty and amputation [2–9], the current gold standard, and most commonly performed treatment involves arthrodesis of the first MTP joint with resection arthroplasty of the lesser metatarsal heads [2]. There have been few studies on joint preserving surgery for rheumatoid forefoot deformities and it has been previously stated
∗ Corresponding author. E-mail address: [email protected] (M. Bhavikatti). 0958-2592/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.foot.2011.12.002
that patients will have poor outcomes in surgical procedures that do not involve fusion of the hallux MTP joint due to recurrent deformities [3,4,10]. Scarf osteotomy of the first metatarsal with a harmonised shortening of the lesser metatarsals by Weil osteotomy has been suggested to result in good correction of forefoot deformities at midterm follow-up [5]. The Scarf osteotomy allows for a wide range of fragment displacement and has inherent stability with relatively simple internal fixation [5]. The Weil osteotomy is an oblique shortening osteotomy which has been recommended for the treatment of the subluxed or dislocated joint and correction of lesser toe deformities by reducing the soft tissue tension [11]. Advantages of joint preserving surgery include maintaining available mobility of the first MTP joint which helps compensate for fixed deformity of the mid and hind-foot, as well as preserving the ability to perform revision surgery in future should progressive joint destruction occur. One study of 30 patients (39 feet) who underwent combined first tarsometatarsal fusion and shortening oblique osteotomies of the second to fourth metatarsals reported improvements in foot function at mean follow-up of 36 months [3]. Fourteen patients had persistent forefoot stiffness and four required removal of hardware. Thordarson et al. reported on joint salvage in 15 feet affected by RA and concluded that patients will
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Fig. 1. Preoperative standing anteroposterior (A) and oblique (B) foot radiographs of a 60-year-old patient with RA, hallux valgus deformity, hammer toes and painful lesser toe callosities. One year postoperative standing anteroposterior (C) and lateral (D) foot radiographs following first ray Scarf osteotomy and second to fourth ray Weil osteotomies. The patient had a stable first ray with correction of lesser toe deformities and complete resolution of pain.
M. Bhavikatti et al. / The Foot 22 (2012) 81–84
have poor surgical outcomes in those that do not involve fusion of the hallux MTP joint [10]. Concerns regarding persistent pain, stiffness and recurrence with this treatment strategy remain [3,10]. The aim of this study was to report the clinical and radiological results of joint preserving surgery for the first MTP joint and lesser toes in 49 patients (66 feet) with rheumatoid forefoot deformities. We hypothesised that joint preserving surgery of the first MTP joint and lesser toes in patients with RA would correct deformity and improve pain at midterm follow-up. 2. Patients and methods Between January 2000 and December 2005, 49 consecutive patients with rheumatoid forefoot deformities (66 feet) underwent Scarf osteotomy of the first metatarsal and/or Weil osteotomy of the lesser metatarsals. There were 44 females and 5 males with a mean age of 56.1 years (17–70 years) and mean follow-up of 51 months (40–65 months) (Fig. 1). Patients were diagnosed with their rheumatoid disease at a mean of 10.5 years (5–20 years) preoperatively. Seventeen patients underwent bilateral procedures. Indications for surgery were disabling foot pain affecting function with painful hallux valgus deformity, prominent lesser toe metatarsal heads and/or hammer toe deformity with callosities. All patients had failed to respond to conservative treatment (insoles and footwear modification). Contraindications to joint salvage were active rheumatoid forefoot synovitis and severe erosive arthritic change in the MTP joints. Fifty-nine feet underwent Scarf osteotomy for hallux valgus with an additional Weil osteotomy performed in 39 feet for lesser toe deformity and pain. Seven feet (three bilateral) underwent isolated Weil osteotomy for lesser toe deformities. The total number of Weil osteotomies performed was 108. Twenty-four feet required an additional fusion of the lesser toe proximal interphalangeal joint for fixed lesser toe hammer toe deformity. Data were collected retrospectively from medical records, clinic reviews and radiographs. The preoperative and postoperative radiographs were analysed independently by the first author. Severity of arthritis in the first MTP joint was categorised into four grades (1–4) as described by Coughlin [2]. Preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) forefoot scores [12] were used to assess clinical outcome. The AOFAS produces a score out of 100 which includes assessment of pain, level of activity, deformity and motion. A subjective scoring system where patients graded their perceived outcomes as either poor, fair, good or excellent was also used, as described by Coughlin [2]. 2.1. Surgical technique The main principle is joint preservation by shortening osteotomy of all symptomatic metatarsals performed at the level of the MTP joints and metatarsal heads. All operations were performed supine with a thigh tourniquet under spinal or general anaesthesia by the senior author. A lateral soft tissue release and excision of prominent osteophytes is performed through a dorsomedial approach to the first MTP joint. Scarf osteotomy was performed on the first ray and internally fixed with two cannulated interfragmentary screws in 59 feet. The Scarf osteotomy is primarily a shortening and lateral translational osteotomy [11]. In this study the average shortening of the first ray was 6 mm (4–12 mm). Medial capsulorrhaphy aids restoration of MTP joint congruity. The four lesser MTP joints are exposed through two dorsal longitudinal incisions centred over the second and fourth inter-metatarsal spaces. When the first metatarsal is shortened by 5 mm or more then Weil osteotomy of the lesser metatarsals is routinely performed to decompress the first MTP joint. Tight soft
83
tissues are released. Weil osteotomy was performed in 46 feet to correct dislocation or subluxation of lesser MTP joints associated with painful callus. In this study the average shortening of the lateral rays was 8 mm. The oblique osteotomy is internally fixed with a single twist-off screw unless it was felt that the bone was too osteopenic to provide adequate stability. The normal anatomical inclination of lesser metatarsal should be restored with equal length of the first and second metatarsals following the rules of Tanaka et al. [13]. An additional lesser toe proximal interphalangeal joint fusion with Kirschner wire fixation was performed in 24 feet to correct persistent fixed flexion deformities. Postoperatively two intravenous doses of cefuroxime were administered and Kirschner wires removed at 4 weeks. Patients were mobilised in heel weightbearing shoes for 6 weeks. 3. Results 3.1. Clinical results Subjectively patients reported their outcome as excellent in 49 feet (74%), good in 9 feet (13.5%), fair in 7 feet (10.5%) and poor in 1 foot (1%). Postoperatively persistent pain was reported in 11 feet, stiffness in 5 feet and recurrence of hallux valgus deformity in 3 feet. Mean preoperative AOFAS score increased from a mean of 39.8 (18–56) preoperatively to 88.7 (48–92) at final follow-up. Preoperatively severe pain was present in 44 feet (67%), moderate pain in 19 feet (29%) and mild pain in 3 feet (4.5%). Postoperatively no pain was reported in 55 feet (83%), mild pain in 4 feet (6%) and moderate pain in 7 feet (10.5%). Preoperatively painful callus under the metatarsal heads was reported in 38 feet. No patients reported painful callus postoperatively. 3.2. Radiographic results Preoperative radiographs showing arthritic changes in the first MTP joint were mild in 19 feet, moderate in 42 feet and severe in 5 feet. Twenty-one lesser toe MTP joints were dislocated and 87 were subluxed. Mean hallux valgus angle (HVA) decreased from a preoperative mean of 32◦ (23–59◦ ) to 14◦ (5–28◦ ) at final followup. Inter-metatarsal angle (IMA) decreased from a preoperative mean of 15◦ (9–21◦ ) to 11◦ (5–14◦ ) at final follow-up. 3.3. Complications One patient developed a superficial wound infection requiring oral antibiotics. Persistent pain was reported in 11 feet, stiffness in 5 feet, recurrence of hallux valgus deformity in 3 feet and recurrence of lesser toe deformity in 5 feet. All three patients who had symptomatic recurrence (HVA > 18◦ and IMA > 11◦ ) of hallux valgus deformity had a preoperative HVA of >45◦ . Active synovitis was the cause of recurrent pain in two patients, failure to restore the natural metatarsal curve with inadequate shortening of the first metatarsal was thought to be the cause of recurrent pain in a further two patients and significant arthritic change in the MTP joints was the cause of continuing pain in the remaining patients. All patients with persistent pain did not request further surgery and were managed non-operatively with orthopaedic footwear and analgesia. One patient had numbness in a lesser toe which resolved after 3 weeks. There were no cases of non-union or osteonecrosis or requirement for removal of hardware. 4. Discussion There have been several different operative procedures described for the treatment of rheumatoid forefoot deformity
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including excision arthroplasty, silicone arthroplasty and amputation [2–9]; however the most commonly performed treatment involves arthrodesis of the first MTP joint with resection arthroplasty of the lesser metatarsal heads [2,14]. Coughlin performed a retrospective review of 32 patients with RA forefoot deformities who underwent arthrodesis of the first MTP joint with resection arthroplasty of the lesser metatarsal heads. Sustained deformity correction and good clinical outcomes (mean AOFAS score 69) were reported at mean follow-up of 108 months; however mild to moderate pain was still present in 62% of feet and 68% still had some degree of limitation clinically. The theoretical benefits of joint salvage in the rheumatoid forefoot are maintenance of first MTP joint mobility which aids toe off during the gait cycle and helps compensate for fixed deformity in the mid and hind-foot. Thordarson et al. reported the results of joint salvage in 15 feet affected by RA and concluded that patients will have poor outcomes in surgical procedures that do not involve fusion of the hallux MTP joint [10]. Graham reported four patients with RA who were treated with resection arthroplasty of the second to fifth metatarsal heads without first MTP joint surgery [14]. Three patients required subsequent first MTP joint fusion for persistent pain and recurrent deformity and the author advised against joint salvage in the rheumatoid forefoot. However recently this has been questioned. Barouk and Barouk reported preliminary results of joint salvage surgery in 34 patients with RA forefoot deformities who underwent Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals [9]. Clinical outcome was not assessed; however 86% of lateral metatarsal heads were preserved and sustained hallux valgus deformity correction was present in 92% of operated feet. The aim of joint preserving surgery in rheumatoid forefoot deformities is not to create a normal foot but to correct gross deformity, alleviate pain, and improve function. We believe the key to a successful outcome is achieving a stable realignment of the first ray to increase weight-bearing along the medial column of the foot, minimise stress on the lateral metatarsal heads and protect the relocated plantar fat pad. This is achieved by shortening all the metatarsals following the rules of Tanaka et al. [13] and laterally translating the first metatarsal with a Scarf osteotomy [9]. This provides longitudinal decompression of the first MTP joint and reduces deforming forces on the correction. In the present series the mean HVA decreased from 32◦ preoperatively to 14◦ at final follow-up which is an acceptable correction, compared with other studies investigating the surgical treatment of hallux valgus [3,4,8]. Berg et al. [4] reviewed 17 patients with RA forefoot deformities who underwent Scarf and Weil osteotomies. At 65 months follow-up, the majority of patients (79%) were satisfied with their result and mean HVA decreased from 41◦ to 23◦ . The main complications we observed with this treatment strategy were persistent pain in 11 feet, stiffness in 5 feet and recurrence of hallux valgus deformity in 3 feet. None of the 11 patients requested further surgery due to their symptoms being too mild to warrant further surgery. The three patients who had recurrence of deformity had severe hallux valgus deformity (>45◦ ) preoperatively which is likely to have predisposed to this. We believe active synovitis was the cause of recurrent pain in two patients, failure to restore the natural metatarsal curve with inadequate shortening of the first metatarsal was the cause of recurrent pain in a further two patients and significant arthritic change in the MTP joints was the cause of continuing pain in the remaining patients. This study suggests joint preserving surgery is effective in moderate to severely damaged MTP joints; however the study did not include patients with extensive joint damage and it is not clear whether
this subgroup of patients should be considered for joint sparing or joint-sacrificing surgery. There are limitations to this study including selection, measurement and interviewer bias. Although the AOFAS is a frequently used scoring system that allows comparison with other studies, SooHoo et al. [15] demonstrated poor correlation between the AOFAS and Medial Outcomes Study Short Form-36 (SF-36) and suggested that the AOFAS may have poor construct validity. However Baumhauer et al. [16] reported good correlation between the AOFAS and validated Foot Function Index [17] in a subgroup analysis of rheumatoid patients. Patients in the current study had less pain and better functional outcome than with the traditional treatment of metatarsal head resection and first MTP joint fusion [2]. In severe hallux valgus deformity with radiological destruction of the first MTP joint we recommend a primary fusion. Medical management of RA is improving and this study has shown that in intermediate to severe stages of the disease, joint preserving surgery by Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals may be performed as an alternative to joint-sacrificing procedures and should be considered as a complement to the various surgical treatments of the rheumatoid forefoot. Conflict of interest None. References [1] Vainio K. Rheumatoid foot. Clinical study with pathological and roentgenological comments. Ann Chir Gynaecol Fenniae (Suppl) 1956;45:1–107. [2] Coughlin MJ. Rheumatoid forefoot reconstruction. A long-term follow up study. J Bone Joint Surg Am 2000;82:322–41. [3] Niki H, Hirano T, Okada H, Beppu M. Combination joint-preserving surgery for forefoot deformity in patients with rheumatoid arthritis. J Bone Joint Surg Br 2010;92:380–6. [4] Berg RP, Kelder W, Olsthoorn PRM, Poll RG. Scarf and Weil osteotomies for correction of rheumatoid forefoot deformities: a review of 20 cases. Foot Ankle Surg 2007;13:35–40. [5] Barouk LS. Scarf osteotomy for hallux valgus correction. Local anatomy, surgical technique, and combination with other forefoot procedures. Foot Ankle Clin 2000;5:525–58. [6] Flint M, Sweetnam R. Amputation of all toes. A review of forty-seven amputations. J Bone Joint Surg Br 1960;42:90–6. [7] Moeckel BH, Sculco TP, Alexiades MM, Dossick PH, Inglis AE, Ranawat CS. The double-stemmed silicone-rubber implant for rheumatoid arthritis of the first metatarsophalangeal joint. Long-term results. J Bone Joint Surg Am 1992;74(4):564–70. [8] Vahvanen V, Piirainen H, Kettunen P. Resection arthroplasty of the metatarsophalangeal joints in rheumatoid arthritis. A follow-up study of 100 patients. Scand J Rheumatol 1980;9:257–65. [9] Barouk LS, Barouk P. Joint-preserving surgery in rheumatoid forefoot: preliminary study with more than two year follow-up. Foot Ankle Clin North Am 2007;12:435–54. [10] Thordarson DB, Aval S, Krieger L. Failure of hallux MP preservation surgery for rheumatoid arthritis. Foot Ankle Int 2002;23:486–90. [11] Weil LS. Scarf osteotomy for correction of hallux valgus. Historical perspective, surgical technique, and results. Foot Ankle Clin 2000;5:559–80. [12] Kitaoka HB, Alexander IJ, Adelaar RS, Nunley JA, Myerson MS, Sanders M. Clinical rating systems for the ankle hindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 1994;15:349–53. [13] Tanaka Y, Takakura Y, Kumai T, Samoto N, Tamai S. Radiographic analysis of hallux valgus. A two-dimensional coordinate system. J Bone Joint Surg Am 1995;77(2):205–13. [14] Graham CE. Rheumatoid forefoot metatarsal head resection without first metatarsophalangeal arthrodesis. Foot Ankle Int 1994;15:689–90. [15] SooHoo NF, Shuler M, Fleming LL. Evaluation of the validity of AODAS Clinical Rating Systems by correlation to the SF-36. Foot Ankle Int 2003;24(January (1)):50–5. [16] Baumhauer JF, Nawoczenski DA, DiGiovanni BF, Wilding GE. Reliability and validity of the American Orthopaedic Foot and Ankle Society Clinical Rating Scale: a pilot study for the hallux and lesser toe. Foot Ankle Int 2006;27(December (12)):1014–9. [17] Budiman-Mak E, Conrad KJ, Roach KE. The Foot Function Index: a measure of foot pain and disability. J Clin Epidemiol 1991;44(6):561–70.