- Email: [email protected]
The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss
Accepted Manuscript Title: The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss Authors: Francesc Malagelada, Matthew J. Welck, Callum Clark PII: DOI: Reference:
S1268-7731(17)30046-2 http://dx.doi.org/doi:10.1016/j.fas.2017.02.009 FAS 1012
To appear in:
Foot and Ankle Surgery
Received date: Revised date: Accepted date:
24-11-2016 18-1-2017 13-2-2017
Please cite this article as: Malagelada Francesc, Welck Matthew J, Clark Callum.The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss.Foot and Ankle Surgery http://dx.doi.org/10.1016/j.fas.2017.02.009 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss
Francesc Malagelada1, Matthew J Welck2, Callum Clark1
1. Foot and Ankle Unit, Orthopaedics and Trauma, Heatherwood and Wexham Park Hospitals, Frimley Health NHS Trust. London Rd, Ascot, Berkshire, SL5 8AA, UK. 2. Foot and Ankle Unit, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, Middlesex, HA7 4LP, UK
Corresponding author: Francesc Malagelada Heatherwood and Wexham Park Hospitals, Frimley Health NHS Trust. London Rd, Ascot, Berkshire, SL5 8AA, UK. Tel. 01344 623333 [email protected]
Preference for illustrations color: Online only
Highlights
Our case series presents a novel technique for arthrodesis of the first MTPJ in the presence of bone loss. Its advantages include its versatility, the potential for restoration of hallux length / alignment and ease of fixation. fusion rate of 100% was achieved at a mean of 9.3 weeks in our series of 8 patients. Only one patient required removal of metalwork and no major complications were encountered.A In all cases the HVA improved postoperatively and the length of hallux also increased consistently especially in those cases which were revised from a non-arthroplasty index surgery (arthrodesis, Keller).
1
ABSTRACT Introduction The operative management of failed first metatarso-phalangeal joint (MTPJ) surgery is often complicated by bone loss and shortening of the hallux. Restoration of first ray length and alignment often cannot be achieved with in situ fusion and reconstruction techniques with bone graft are therefore required. We present a novel technique of longitudinal (proximo-distal) bone dowel arthrodesis for first MTPJ arthrodesis with bone loss. Materials And Methods Between August 2007 and February 2015, eight patients have been treated by the senior author with this technique. The mean age at surgery was 60.5 years (range 45 to 80) with seven females and one male. Index surgery was MTPJ arthrodesis (three
patients),
Keller
excision
arthroplasty
(two
patients),
MTPJ
hemiarthroplasty (two patients) and silastic arthroplasty (one patient). Clinical and radiological fusion was assessed and other radiological measurements included hallux valgus angle (HVA) and length of the hallux (LOH). Results All patients achieved fusion at a mean of 9.3 weeks (range 6-12) from surgery and only one patient required removal of metalwork. There were no major complications. The HVA improved in all cases from 21.4 +- 2.8 pre-operatively to 11.6 +-3.5 post-operatively (p>0.05). The LOH also increased in all cases from 82.1 +-8.3 mm to 86.7 +-8.2 mm (p>0.05). The subgroup of patients who were revised from an arthroplasty, where maintenance of length rather than increase in length 2
was desirable (hemiarthroplasty, silastic) had significantly lower increase in LOH than those revised from a non-arthroplasty index surgery (arthrodesis, Keller) (p= 0.029). Conclusion The dowel technique is successful for first MTPJ arthrodesis revision surgery with optimal union rates and satisfactory radiographic and clinical outcomes. It is an effective and versatile option for managing bone loss and deformity of the hallux.
Keywords: arthrodesis; arthroplasty; first metatarsophalangeal joint; hallux rigidus; bone block
INTRODUCTION The operative management of failed first metatarso-phalangeal joint (MTPJ) surgery is sometimes complicated by significant bone loss and shortening of the first ray. When undertaking revision surgery for failed Keller’s or first MTPJ implant arthroplasty, the loss of bone can be substantial. Arthrodesis of the hallux MTPJ is a recognised technique when managing failed hallux valgus or rigidus surgery [1-9]. However, maintaining the length of the first ray in the presence of bone loss and/or avascular bone is an important consideration, to preserve the biomechanics of the forefoot and prevent transfer metatarsalgia [10]. Restoration of hallux length and alignment is hardly ever 3
achieved with in situ fusion, and reconstruction techniques with structural bone graft are therefore required. Arthrodesis techniques with structural graft can be technically challenging and have been associated with a higher incidence of non-union and delayed union, higher re-operation rate, and poorer outcome scores than primary fusions. [1,2]. Most described techniques utilise an interposition bone block allograft or autograft with rigid internal fixation. The use of ‘dowels’ of bone graft, rather than blocks, has been described in Lisfranc, ankle and talonavicular joint fusions. [11-13] and a dorso-plantar dowel technique has also been reported for primary MTPJ arthrodesis. [14] We describe a novel technique of longitudinal (proximo-distal) bone dowel arthrodesis for first MTPJ arthrodesis with bone loss and review the clinical and radiological outcomes of our technique.
MATERIALS AND METHODS Patient population A retrospective review was conducted of all cases using the dowel technique for first MTPJ arthrodesis in revision surgery in our institution. Between August 2007 and February 2015, there were 8 such procedures performed by the senior author (CC). There were 7 females and 1 male, with a mean age of 60.5 years (range 4580) at the time of surgery. Index surgery was MTPJ arthrodesis (3 patients), Keller arthroplasty (2 patients), MTPJ hemiarthroplasty (2 patients), and silastic arthroplasty (1 patient). One patient suffered rheumatoid arthritis, but there were 4
no cases of diabetes mellitus, peripheral vascular disease or smoking. No patients were excluded from the study and none were lost to follow-up. All patients presented with a painful hallux and/or transfer metatarsalgia following failed previous 1st MTPJ surgery, and had bone loss deemed significant enough to require a structural interposition bone graft. Four patients had a concurrent procedure performed (Table 1).
Operative technique Patients were placed in a supine position with a thigh tourniquet and draped to include the ipsilateral iliac crest. The joint was approached through the previous incision, which was dorsal in 6 cases and medial in two. Full thickness flaps were raised including the subcutaneous tissue and the periosteum. Any previous metalwork or silastic remnants were removed and the joint was debrided. The base of the proximal phalanx and the metatarsal head were prepared down to bleeding cancellous bone and intra-medullary cavities were made using a 3.5mm drill and curette. The size of the graft required to achieve appropriate lengthening of the first ray was measured with a ruler. A structural bi-cortical autograft measuring an additional 2 cm from the measured bone gap was harvested from the iliac crest and was contoured to fit into the first metatarsal and proximal phalangeal holes (a tri-cortical graft would be too large in diameter). Cancellous bone graft was also harvested.
5
The dowel was inserted into the metatarsal cavity first and then the proximal phalangeal cavity. The position of the toe was assessed against a flat surface to simulate the weight-bearing situation, as per a standard arthrodesis. The correct position was held easily with the help of the dowel, which provided intrinsic stability while internal fixation was performed. We used a dorsal plate for fixation (VA-LCP forefoot/midfoot system, Synthes, Welwyn Garden City, UK). Cancellous bone graft from the iliac crest was packed in around the dowel. The wound was closed and dressed in the usual fashion. Concurrent surgery was performed in 4 patients (Table 1). Post-operative protocol All procedures were performed as day cases with patients discharged on the day of surgery. Full weight bearing on a heel-wedged shoe (Darco Orthowedge, Darco International Inc, Huntington, WV, USA) was allowed for the first 6 to 9 weeks. Wounds were examined and sutures trimmed at 2 weeks. Radiographs (standing antero-posterior and lateral views of the foot) were obtained at 6 weeks and depending on the fusion progression, the Darco shoe was discontinued or extended for a further 3 weeks. If no signs of fusion were observed the following appointment was scheduled at 9 weeks or 12 weeks post-operatively with repeat radiographs. Outcome measures A retrograde review of clinical notes was performed for post-operative complications and the need for additional surgical procedures. At post-operative follow-up patients were assessed clinically and radiographically. The primary
6
outcome variable was fusion success, and secondary outcome measures were complications, hallux valgus angle (HVA) and length of hallux (LOH). The clinical criteria for fusion included absence of swelling, pain or warmth and radiographic criteria were maintenenance of position, absence of peri-prosthetic lucency or other signs of micro-motion and bridging trabeculae on AP and lateral views. Radiographic measurements were also obtained both pre- and post-operatively including the HVA and LOH. We used the description by Myerson et al. to determine the LOH from the base of the first metatarsal to the distal end of the proximal phalanx, or from the tarsometatarsal joint to the interphalangeal joint on lateral standing radiographs. [1] Statistical analysis Statistical analysis was performed using SPSS 19 (SPSS Inc., Chicago, IL). Descriptive results are presented as mean +- standard deviation (SD). Analysis of variables between subgroups was performed with Mann-Whitney U test. Differences were considered significant when p<0.05 The study was approved by our Institutional Clinical Effectiveness Unit and informed consent was obtained from all patients included.
RESULTS Mean length of post-operative follow-up was 37.4 months (range 12 to 102). Fusion occurred in all patients according to both clinical and radiographic criteria at a mean of 9.3 weeks (range 6-12).
7
There were no major complications in our series of patients. One patient required removal of metalwork (13%) due to discomfort in the absence of infection and in another the plate was prominent but removal was not deemed necessary. There was one case of partial loss of sensation in the big toe, which resolved. One patient (index surgery non-union) suffered from unremitting pain at the latest follow-up (38 months post-operation) but there were no clinical signs of complex regional pain syndrome (CRPS), neurological or vascular deficiency and a CT scan confirmed solid fusion of the 1st MTPJ. Despite the absence of clinical signs we suspected atypical CRPS and the patient was treated symptomatically. No complications were encountered regarding bone graft donor site. There were no cases of superficial or deep infection or metalwork failure (TABLE 1). The radiographic HVA improved in all cases from 21.4 +-2.8 pre-operatively to 11.6 +-3.5 post-operatively (p>0.05). The LOH also increased in all cases an average of 4.6 mm (p>0.05). In the subgroup of patients where an implant was initially in situ the LOH remained practically unchanged (mean increase of 2 mm) compared to those patients where there was no implant and the LOH increased by a mean of 6.4 mm. This difference in mean between the two subgroups was statistically significant. (p=0.029) (TABLE 2).
DISCUSSION A number of techniques for first MTPJ arthrodesis with restoration of toe length have been described, most utilising interpositional bone block grafts. The preparation of the first MTPJ complementary bone surfaces has been performed
8
using flat cuts [1], cone and socket [15], dome-shape [4], and dowel [14] grafts. Tauro and Muirhead used a dowel for first MTPJ primary arthrodesis although the tunnel was across the joint from dorsal to plantar. They hypothesized that because the collateral ligaments were left intact, the stability of the MTPJ was retained and the dowel provided extra stability and maintained length of the toe without the need for internal fixation. [12] Union rates found in the literature for revision first MTPJ arthrodesis have been of 80% to 100%. Hecht et al reported an 80% union rate using flat cuts in a case series of arthrodesis for salvage after failed implant arthroplasty. [5] More recent studies have improved rates to 90% and 100% with similar techniques using flat cuts. [6,7,9] Some authors have favoured allografts in either primary or revision first MTPJ arthrodesis. [1,4] We present a small series of patients using a novel iliac crest autograft dowel technique for the salvage of failed first MTPJ procedures with associated bone loss and report a 100% union rate. Although donor site morbidity is well-recognized following iliac crest bone graft, we have not experienced any complications related to graft harvesting in this series. In our experience, the use of autograft reduces surgical costs and promotes union. We favoured a dowel-shaped bone graft and joint preparation because of its reproducibility and inherent stability. It can be used to restore the length of large bony defects resulting from extraction of arthroplasties. So-called dowel techniques have been used in other joints: Belt et al. and Stranks et al. used a dowel technique in the ankle and Withey et al in the tarso-metatarsal joints. [1113]
9
The dowel graft in our technique is press-fitted into the fusing surfaces and is thus both very versatile and allows for maintenance of hallux length and alignment. The fusion rate is high and we feel this is due to particular aspects of the technique. By drilling holes in which the dowel will be inserted, the contact area is increased in the site of fusion. Moreover, the intramedullary position of the dowel graft is directly in contact with the endosteal blood supply. Both the increased contact area and the increased blood supply may play a positive role in fusion. Cancellous bone graft surrounding the dowel contributes to bone formation and the procedure therefore benefits from the advantages of both structural and morselized bone graft. The technique also allows the surgeon to independently adjust the position of the joint desired for fusion without the need for further bone cuts. The alignment can be easily controlled due to the intrinsic stability of the intramedullary dowel, extending into the metatarsal and proximal phalanx. With the reference of a flat surface to simulate weight-bearing the final position can then be fine-tuned before applying the dorsal plate. Radiographic analysis showed a statistically non-significant improvement in the HVA of all patients, achieved by realigning the hallux to the desired position using the dowel bone graft. The LOH was increased by a mean of 4.5 mm, which is desirable in minimizing transfer metatarsalgia. Patients, who were revised from an implant arthroplasty experienced practically no lengthening when compared to the 6.4 mm of lengthening seen in those with no implant. This statistically significant difference between the two subgroups could be explained by the fact that the space used by the bone graft was previously already occupied by the prosthesis hence hallux lengthening was not necessary in the arthroplasty subgroup – the importance in these cases is to avoid shortening. On the contrary, 10
in those cases of previous failed fusion or Keller excision arthroplasty the hallux is usually shortened by removal of bone during the primary operation and lengthening is advised. We recommend measuring the graft to be harvested to at least 2 cm more than the gap left between the base of the proximal phalanx and the metatarsal to account for intramedullary recession of the bone graft on each side of the joint. The mean lengthening achieved with this technique compares to that reported in the literature, which ranges from 4.2mm to 13mm. [1,3,7] Myerson achieved the highest LOH of 13mm by lengthening the EHL tendon and assessing intraoperatively the maximal possible distraction without causing skin ischaemia. [1] Other authors have downsized the interpositional bone graft in order to avoid skin problems and we agree with this approach. [3] With the use of our dowel technique the graft is not bulky and will therefore not further compromise the sometimes already poor quality soft tissue envelope found in these cases. There are several limitations to this study. This was a retrospective case series with a small number of patients and without a control group to compare the procedure with. We report no functional outcome measures, although would expect that with a high union rate, a high mean outcome score could reasonably be assumed, when compared to other modes of fusion in this clinical scenario. The long term follow up with absence of any dowel fractures also support good clinical outcomes. This technique is described for the first time in the literature and brings a novel concept in the surgery of the first MTPJ. The optimal fusion rates and lack of major complications demonstrate its reliability in a procedure otherwise considered
11
relatively problematic and complex. We conclude that the dowel technique is successful for first MTPJ arthrodesis revision surgery and convenient to manage bone loss and deformity of the hallux.
Conflict of interest All authors declare that they have no relationships/conditions/circumstances that present a potential conflict of interest for the preparation of this manuscript
12
REFERENCES [1]. Myerson MS, Schon LC, McGuigan FX, Oznur A. Result of arthrodesis of the hallux metatarsophalangeal joint using bone graft for restoration of length. Foot Ankle Int. 2000;21(4):297-306.
[2]. Schuh R, Trnka HJ. First metatarsophalangeal arthrodesis for severe bone loss. Foot Ankle Clin. 2011;16:13-20.
[3]. Malhotra K, Nunn T, Qamar F, Rao V, Shanker J. Interposition bone block arthrodesis for revision hallux metatarsophalangeal joint surgery: a case series. Foot Ankle Int. 2015 ;36:556-64. [4]. Luk PC, Johnson JE, McCormick JJ, Klein SE. First Metatarsophalangeal Joint Arthrodesis Technique With Interposition Allograft Bone Block. Foot Ankle Int. 2015 ;36:936-43. [5]. Hecht PJ, Gibbons MJ, Wapner KL, Cooke C, Hoisington SA. Arthrodesis of the first metatarsophalangeal joint to salvage failed silicone implant arthroplasty. Foot Ankle Int. 1997;18(7):383-390.
[6]. Bhosale A, Munoruth A, Blundell C, Flowers MJ, Jones, S, Davies MB. Complex primary arthrodesis of the first metatarsophalangeal joint after bone loss. Foot Ankle Int. 2011;32(10):968-972.
[7]. Brodsky JW, Ptaszek AJ, Morris SG. Salvage first MTP arthrodesis utilizing ICBG: clinical evaluation and outcome. Foot Ankle Int. 2000;21(4):290-296.
13
[8]. Coughlin MJ, Mann RA. Arthrodesis of the first metatarsophalangeal joint as salvage for the failed Keller procedure. J Bone Joint Surg Am. 1987;69(1):68-75.
[9]. Garras DN, Durinka JB, Bercik M, Miller AG, Raikin SM. Conversion arthrodesis for failed first metatarsophalangeal joint hemiarthroplasty. Foot Ankle Int. 2013 Sep;34(9):1227-32.
[10]. Cancilleri F, Marinozzi A, Martinelli N, et al. Comparison of plantar pressure, clinical, and radiographic changes of the forefoot after biplanar Austin osteotomy and triplanar Bocosteotomy in patients with mild hallux valgus. Foot Ankle Int. 2008;29(8):817-824.
[11]. Stranks GJ, Cecil T, Jeffery IT. Anterior ankle arthrodesis with cross-screw fixation. A dowel graft method used in 20 cases. J Bone Joint Surg Br. 1994;76:9436. [12]. Belt EA, Mäenpää H, Lehto MU. Outcome of ankle arthrodesis performed by dowel technique in patients with rheumatic disease. Foot Ankle Int. 2001 Aug;22(8):666-9. [13]. Withey CJ, Murphy AL, Horner R. Tarsometatarsal joint arthrodesis with trephine joint resection and dowel calcaneal bone graft. J Foot Ankle Surg. 2014;53:243-7. [14]. Tauro B, Muirhead A. Dowel technique for metatarsophalangeal joint
14
arthrodesis in hallux rigidus. Foot 2000;10:75–77.
[15]. McKeever DC. Arthrodesis of the first metatarsophalangeal joint for hallux valgus, hallux rigidus, and metatarsus primus varus. J Bone Joint Surg Am. 1952;34(1):129-134.
15
FIGURE LEGENDS Figure 1. Preparation of the joint with intra-medullary holes in the base of the proximal phalanx and the metatarsal head.
16
Figure 2. Structural iliac crest bone graft prepared in a dowel shape of the required size and contoured to fit into the intramedullary holes
17
Figure 3. Dowel bone graft inserted in the MTPJ and evidence of the lengthening achieved.
18
Figure 4. Low-profile plate inserted for internal fixation and the remaining gap that is packed with cancellous bone graft.
19
Figure 5. A. Pre-operative radiographs of failed first and second metatarsophalangeal joint (MTPJ) hemiarthroplasties. B. Post-operative radiographs 16 weeks following dowel revision first MTPJ arthrodesis and second MTPJ Stainsby procedure.
20
TABLE 1. Patients demographics and clinical data. FU: Follow-up (in months), RA: Rheumatoid arthritis, BMI: Body mass index. Case
Age/Sex
FU
1
60 / ♀
102
2 3 4
45 / ♀ 55 / ♀ 65 / ♀
38 40 40
5 6
80 / ♀ 55 / ♂
37 12
7
62 / ♀
12
8
62 / ♀
18
Mean
60.5
37.4
Primary Procedure Keller Non-union Silastic Hemiarthroplasty Proximal phalanx Non-union Non-union after malunion revision Keller
Hemiarthroplasty Metatarsal
Comorbidities RA
Concurrent treatment 2nd toe Stainsby
Complications
Unremitting pain Removal of plate BMI 32
2nd toe fusion
PIPJ
BMI 35 Prominent plate, temporary numbness Polycythemia vera
2nd toe Stainsby+PIPJ fusion, 3rd toe PIPJ fusion Revision of 2nd toe hemiarthroplasty to Stainsby
21
Table 2. Radiographic parameters. HVA: Hallux valgus angle, LOH: Length of hallux, Diff: Difference, SD: Standard deviation. Grey fields are patients in the arthroplasty subgroup (hemiarthroplasty, sylastic arthroplasty). White fields are those patients in the nonarthroplasty subgroup (fusion, Keller arthroplasty). When these two subgroups were compared, the difference of means in HVA was p>0.05 and the difference of means in LOH was p=0.025 (statistically significant). Case 1 2 3 4 5 6 7 8 Mean (SD)
Pre HVA 21 20 18 21 22 19 25 25 21.4 (2.6)
Post HVA 12 10 11 7 15 8 15 15 11.6 (3.2)
Diff HVA -11 -10 -7 -4 -7 -7 -10 -10 -8.2 (2.4)
Pre LOH 82 82 88 85 66 90 77 87 82.1 (7.7)
Post LOH 87 88 89 88 70 97 86 89 86.8 (7.6)
Diff LOH -5 -6 -1 -3 -4 -7 -9 -2 -4.6 (2.7)
22
S1268-7731(17)30046-2 http://dx.doi.org/doi:10.1016/j.fas.2017.02.009 FAS 1012
To appear in:
Foot and Ankle Surgery
Received date: Revised date: Accepted date:
24-11-2016 18-1-2017 13-2-2017
Please cite this article as: Malagelada Francesc, Welck Matthew J, Clark Callum.The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss.Foot and Ankle Surgery http://dx.doi.org/10.1016/j.fas.2017.02.009 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss
Francesc Malagelada1, Matthew J Welck2, Callum Clark1
1. Foot and Ankle Unit, Orthopaedics and Trauma, Heatherwood and Wexham Park Hospitals, Frimley Health NHS Trust. London Rd, Ascot, Berkshire, SL5 8AA, UK. 2. Foot and Ankle Unit, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, Middlesex, HA7 4LP, UK
Corresponding author: Francesc Malagelada Heatherwood and Wexham Park Hospitals, Frimley Health NHS Trust. London Rd, Ascot, Berkshire, SL5 8AA, UK. Tel. 01344 623333 [email protected]
Preference for illustrations color: Online only
Highlights
Our case series presents a novel technique for arthrodesis of the first MTPJ in the presence of bone loss. Its advantages include its versatility, the potential for restoration of hallux length / alignment and ease of fixation. fusion rate of 100% was achieved at a mean of 9.3 weeks in our series of 8 patients. Only one patient required removal of metalwork and no major complications were encountered.A In all cases the HVA improved postoperatively and the length of hallux also increased consistently especially in those cases which were revised from a non-arthroplasty index surgery (arthrodesis, Keller).
1
ABSTRACT Introduction The operative management of failed first metatarso-phalangeal joint (MTPJ) surgery is often complicated by bone loss and shortening of the hallux. Restoration of first ray length and alignment often cannot be achieved with in situ fusion and reconstruction techniques with bone graft are therefore required. We present a novel technique of longitudinal (proximo-distal) bone dowel arthrodesis for first MTPJ arthrodesis with bone loss. Materials And Methods Between August 2007 and February 2015, eight patients have been treated by the senior author with this technique. The mean age at surgery was 60.5 years (range 45 to 80) with seven females and one male. Index surgery was MTPJ arthrodesis (three
patients),
Keller
excision
arthroplasty
(two
patients),
MTPJ
hemiarthroplasty (two patients) and silastic arthroplasty (one patient). Clinical and radiological fusion was assessed and other radiological measurements included hallux valgus angle (HVA) and length of the hallux (LOH). Results All patients achieved fusion at a mean of 9.3 weeks (range 6-12) from surgery and only one patient required removal of metalwork. There were no major complications. The HVA improved in all cases from 21.4 +- 2.8 pre-operatively to 11.6 +-3.5 post-operatively (p>0.05). The LOH also increased in all cases from 82.1 +-8.3 mm to 86.7 +-8.2 mm (p>0.05). The subgroup of patients who were revised from an arthroplasty, where maintenance of length rather than increase in length 2
was desirable (hemiarthroplasty, silastic) had significantly lower increase in LOH than those revised from a non-arthroplasty index surgery (arthrodesis, Keller) (p= 0.029). Conclusion The dowel technique is successful for first MTPJ arthrodesis revision surgery with optimal union rates and satisfactory radiographic and clinical outcomes. It is an effective and versatile option for managing bone loss and deformity of the hallux.
Keywords: arthrodesis; arthroplasty; first metatarsophalangeal joint; hallux rigidus; bone block
INTRODUCTION The operative management of failed first metatarso-phalangeal joint (MTPJ) surgery is sometimes complicated by significant bone loss and shortening of the first ray. When undertaking revision surgery for failed Keller’s or first MTPJ implant arthroplasty, the loss of bone can be substantial. Arthrodesis of the hallux MTPJ is a recognised technique when managing failed hallux valgus or rigidus surgery [1-9]. However, maintaining the length of the first ray in the presence of bone loss and/or avascular bone is an important consideration, to preserve the biomechanics of the forefoot and prevent transfer metatarsalgia [10]. Restoration of hallux length and alignment is hardly ever 3
achieved with in situ fusion, and reconstruction techniques with structural bone graft are therefore required. Arthrodesis techniques with structural graft can be technically challenging and have been associated with a higher incidence of non-union and delayed union, higher re-operation rate, and poorer outcome scores than primary fusions. [1,2]. Most described techniques utilise an interposition bone block allograft or autograft with rigid internal fixation. The use of ‘dowels’ of bone graft, rather than blocks, has been described in Lisfranc, ankle and talonavicular joint fusions. [11-13] and a dorso-plantar dowel technique has also been reported for primary MTPJ arthrodesis. [14] We describe a novel technique of longitudinal (proximo-distal) bone dowel arthrodesis for first MTPJ arthrodesis with bone loss and review the clinical and radiological outcomes of our technique.
MATERIALS AND METHODS Patient population A retrospective review was conducted of all cases using the dowel technique for first MTPJ arthrodesis in revision surgery in our institution. Between August 2007 and February 2015, there were 8 such procedures performed by the senior author (CC). There were 7 females and 1 male, with a mean age of 60.5 years (range 4580) at the time of surgery. Index surgery was MTPJ arthrodesis (3 patients), Keller arthroplasty (2 patients), MTPJ hemiarthroplasty (2 patients), and silastic arthroplasty (1 patient). One patient suffered rheumatoid arthritis, but there were 4
no cases of diabetes mellitus, peripheral vascular disease or smoking. No patients were excluded from the study and none were lost to follow-up. All patients presented with a painful hallux and/or transfer metatarsalgia following failed previous 1st MTPJ surgery, and had bone loss deemed significant enough to require a structural interposition bone graft. Four patients had a concurrent procedure performed (Table 1).
Operative technique Patients were placed in a supine position with a thigh tourniquet and draped to include the ipsilateral iliac crest. The joint was approached through the previous incision, which was dorsal in 6 cases and medial in two. Full thickness flaps were raised including the subcutaneous tissue and the periosteum. Any previous metalwork or silastic remnants were removed and the joint was debrided. The base of the proximal phalanx and the metatarsal head were prepared down to bleeding cancellous bone and intra-medullary cavities were made using a 3.5mm drill and curette. The size of the graft required to achieve appropriate lengthening of the first ray was measured with a ruler. A structural bi-cortical autograft measuring an additional 2 cm from the measured bone gap was harvested from the iliac crest and was contoured to fit into the first metatarsal and proximal phalangeal holes (a tri-cortical graft would be too large in diameter). Cancellous bone graft was also harvested.
5
The dowel was inserted into the metatarsal cavity first and then the proximal phalangeal cavity. The position of the toe was assessed against a flat surface to simulate the weight-bearing situation, as per a standard arthrodesis. The correct position was held easily with the help of the dowel, which provided intrinsic stability while internal fixation was performed. We used a dorsal plate for fixation (VA-LCP forefoot/midfoot system, Synthes, Welwyn Garden City, UK). Cancellous bone graft from the iliac crest was packed in around the dowel. The wound was closed and dressed in the usual fashion. Concurrent surgery was performed in 4 patients (Table 1). Post-operative protocol All procedures were performed as day cases with patients discharged on the day of surgery. Full weight bearing on a heel-wedged shoe (Darco Orthowedge, Darco International Inc, Huntington, WV, USA) was allowed for the first 6 to 9 weeks. Wounds were examined and sutures trimmed at 2 weeks. Radiographs (standing antero-posterior and lateral views of the foot) were obtained at 6 weeks and depending on the fusion progression, the Darco shoe was discontinued or extended for a further 3 weeks. If no signs of fusion were observed the following appointment was scheduled at 9 weeks or 12 weeks post-operatively with repeat radiographs. Outcome measures A retrograde review of clinical notes was performed for post-operative complications and the need for additional surgical procedures. At post-operative follow-up patients were assessed clinically and radiographically. The primary
6
outcome variable was fusion success, and secondary outcome measures were complications, hallux valgus angle (HVA) and length of hallux (LOH). The clinical criteria for fusion included absence of swelling, pain or warmth and radiographic criteria were maintenenance of position, absence of peri-prosthetic lucency or other signs of micro-motion and bridging trabeculae on AP and lateral views. Radiographic measurements were also obtained both pre- and post-operatively including the HVA and LOH. We used the description by Myerson et al. to determine the LOH from the base of the first metatarsal to the distal end of the proximal phalanx, or from the tarsometatarsal joint to the interphalangeal joint on lateral standing radiographs. [1] Statistical analysis Statistical analysis was performed using SPSS 19 (SPSS Inc., Chicago, IL). Descriptive results are presented as mean +- standard deviation (SD). Analysis of variables between subgroups was performed with Mann-Whitney U test. Differences were considered significant when p<0.05 The study was approved by our Institutional Clinical Effectiveness Unit and informed consent was obtained from all patients included.
RESULTS Mean length of post-operative follow-up was 37.4 months (range 12 to 102). Fusion occurred in all patients according to both clinical and radiographic criteria at a mean of 9.3 weeks (range 6-12).
7
There were no major complications in our series of patients. One patient required removal of metalwork (13%) due to discomfort in the absence of infection and in another the plate was prominent but removal was not deemed necessary. There was one case of partial loss of sensation in the big toe, which resolved. One patient (index surgery non-union) suffered from unremitting pain at the latest follow-up (38 months post-operation) but there were no clinical signs of complex regional pain syndrome (CRPS), neurological or vascular deficiency and a CT scan confirmed solid fusion of the 1st MTPJ. Despite the absence of clinical signs we suspected atypical CRPS and the patient was treated symptomatically. No complications were encountered regarding bone graft donor site. There were no cases of superficial or deep infection or metalwork failure (TABLE 1). The radiographic HVA improved in all cases from 21.4 +-2.8 pre-operatively to 11.6 +-3.5 post-operatively (p>0.05). The LOH also increased in all cases an average of 4.6 mm (p>0.05). In the subgroup of patients where an implant was initially in situ the LOH remained practically unchanged (mean increase of 2 mm) compared to those patients where there was no implant and the LOH increased by a mean of 6.4 mm. This difference in mean between the two subgroups was statistically significant. (p=0.029) (TABLE 2).
DISCUSSION A number of techniques for first MTPJ arthrodesis with restoration of toe length have been described, most utilising interpositional bone block grafts. The preparation of the first MTPJ complementary bone surfaces has been performed
8
using flat cuts [1], cone and socket [15], dome-shape [4], and dowel [14] grafts. Tauro and Muirhead used a dowel for first MTPJ primary arthrodesis although the tunnel was across the joint from dorsal to plantar. They hypothesized that because the collateral ligaments were left intact, the stability of the MTPJ was retained and the dowel provided extra stability and maintained length of the toe without the need for internal fixation. [12] Union rates found in the literature for revision first MTPJ arthrodesis have been of 80% to 100%. Hecht et al reported an 80% union rate using flat cuts in a case series of arthrodesis for salvage after failed implant arthroplasty. [5] More recent studies have improved rates to 90% and 100% with similar techniques using flat cuts. [6,7,9] Some authors have favoured allografts in either primary or revision first MTPJ arthrodesis. [1,4] We present a small series of patients using a novel iliac crest autograft dowel technique for the salvage of failed first MTPJ procedures with associated bone loss and report a 100% union rate. Although donor site morbidity is well-recognized following iliac crest bone graft, we have not experienced any complications related to graft harvesting in this series. In our experience, the use of autograft reduces surgical costs and promotes union. We favoured a dowel-shaped bone graft and joint preparation because of its reproducibility and inherent stability. It can be used to restore the length of large bony defects resulting from extraction of arthroplasties. So-called dowel techniques have been used in other joints: Belt et al. and Stranks et al. used a dowel technique in the ankle and Withey et al in the tarso-metatarsal joints. [1113]
9
The dowel graft in our technique is press-fitted into the fusing surfaces and is thus both very versatile and allows for maintenance of hallux length and alignment. The fusion rate is high and we feel this is due to particular aspects of the technique. By drilling holes in which the dowel will be inserted, the contact area is increased in the site of fusion. Moreover, the intramedullary position of the dowel graft is directly in contact with the endosteal blood supply. Both the increased contact area and the increased blood supply may play a positive role in fusion. Cancellous bone graft surrounding the dowel contributes to bone formation and the procedure therefore benefits from the advantages of both structural and morselized bone graft. The technique also allows the surgeon to independently adjust the position of the joint desired for fusion without the need for further bone cuts. The alignment can be easily controlled due to the intrinsic stability of the intramedullary dowel, extending into the metatarsal and proximal phalanx. With the reference of a flat surface to simulate weight-bearing the final position can then be fine-tuned before applying the dorsal plate. Radiographic analysis showed a statistically non-significant improvement in the HVA of all patients, achieved by realigning the hallux to the desired position using the dowel bone graft. The LOH was increased by a mean of 4.5 mm, which is desirable in minimizing transfer metatarsalgia. Patients, who were revised from an implant arthroplasty experienced practically no lengthening when compared to the 6.4 mm of lengthening seen in those with no implant. This statistically significant difference between the two subgroups could be explained by the fact that the space used by the bone graft was previously already occupied by the prosthesis hence hallux lengthening was not necessary in the arthroplasty subgroup – the importance in these cases is to avoid shortening. On the contrary, 10
in those cases of previous failed fusion or Keller excision arthroplasty the hallux is usually shortened by removal of bone during the primary operation and lengthening is advised. We recommend measuring the graft to be harvested to at least 2 cm more than the gap left between the base of the proximal phalanx and the metatarsal to account for intramedullary recession of the bone graft on each side of the joint. The mean lengthening achieved with this technique compares to that reported in the literature, which ranges from 4.2mm to 13mm. [1,3,7] Myerson achieved the highest LOH of 13mm by lengthening the EHL tendon and assessing intraoperatively the maximal possible distraction without causing skin ischaemia. [1] Other authors have downsized the interpositional bone graft in order to avoid skin problems and we agree with this approach. [3] With the use of our dowel technique the graft is not bulky and will therefore not further compromise the sometimes already poor quality soft tissue envelope found in these cases. There are several limitations to this study. This was a retrospective case series with a small number of patients and without a control group to compare the procedure with. We report no functional outcome measures, although would expect that with a high union rate, a high mean outcome score could reasonably be assumed, when compared to other modes of fusion in this clinical scenario. The long term follow up with absence of any dowel fractures also support good clinical outcomes. This technique is described for the first time in the literature and brings a novel concept in the surgery of the first MTPJ. The optimal fusion rates and lack of major complications demonstrate its reliability in a procedure otherwise considered
11
relatively problematic and complex. We conclude that the dowel technique is successful for first MTPJ arthrodesis revision surgery and convenient to manage bone loss and deformity of the hallux.
Conflict of interest All authors declare that they have no relationships/conditions/circumstances that present a potential conflict of interest for the preparation of this manuscript
12
REFERENCES [1]. Myerson MS, Schon LC, McGuigan FX, Oznur A. Result of arthrodesis of the hallux metatarsophalangeal joint using bone graft for restoration of length. Foot Ankle Int. 2000;21(4):297-306.
[2]. Schuh R, Trnka HJ. First metatarsophalangeal arthrodesis for severe bone loss. Foot Ankle Clin. 2011;16:13-20.
[3]. Malhotra K, Nunn T, Qamar F, Rao V, Shanker J. Interposition bone block arthrodesis for revision hallux metatarsophalangeal joint surgery: a case series. Foot Ankle Int. 2015 ;36:556-64. [4]. Luk PC, Johnson JE, McCormick JJ, Klein SE. First Metatarsophalangeal Joint Arthrodesis Technique With Interposition Allograft Bone Block. Foot Ankle Int. 2015 ;36:936-43. [5]. Hecht PJ, Gibbons MJ, Wapner KL, Cooke C, Hoisington SA. Arthrodesis of the first metatarsophalangeal joint to salvage failed silicone implant arthroplasty. Foot Ankle Int. 1997;18(7):383-390.
[6]. Bhosale A, Munoruth A, Blundell C, Flowers MJ, Jones, S, Davies MB. Complex primary arthrodesis of the first metatarsophalangeal joint after bone loss. Foot Ankle Int. 2011;32(10):968-972.
[7]. Brodsky JW, Ptaszek AJ, Morris SG. Salvage first MTP arthrodesis utilizing ICBG: clinical evaluation and outcome. Foot Ankle Int. 2000;21(4):290-296.
13
[8]. Coughlin MJ, Mann RA. Arthrodesis of the first metatarsophalangeal joint as salvage for the failed Keller procedure. J Bone Joint Surg Am. 1987;69(1):68-75.
[9]. Garras DN, Durinka JB, Bercik M, Miller AG, Raikin SM. Conversion arthrodesis for failed first metatarsophalangeal joint hemiarthroplasty. Foot Ankle Int. 2013 Sep;34(9):1227-32.
[10]. Cancilleri F, Marinozzi A, Martinelli N, et al. Comparison of plantar pressure, clinical, and radiographic changes of the forefoot after biplanar Austin osteotomy and triplanar Bocosteotomy in patients with mild hallux valgus. Foot Ankle Int. 2008;29(8):817-824.
[11]. Stranks GJ, Cecil T, Jeffery IT. Anterior ankle arthrodesis with cross-screw fixation. A dowel graft method used in 20 cases. J Bone Joint Surg Br. 1994;76:9436. [12]. Belt EA, Mäenpää H, Lehto MU. Outcome of ankle arthrodesis performed by dowel technique in patients with rheumatic disease. Foot Ankle Int. 2001 Aug;22(8):666-9. [13]. Withey CJ, Murphy AL, Horner R. Tarsometatarsal joint arthrodesis with trephine joint resection and dowel calcaneal bone graft. J Foot Ankle Surg. 2014;53:243-7. [14]. Tauro B, Muirhead A. Dowel technique for metatarsophalangeal joint
14
arthrodesis in hallux rigidus. Foot 2000;10:75–77.
[15]. McKeever DC. Arthrodesis of the first metatarsophalangeal joint for hallux valgus, hallux rigidus, and metatarsus primus varus. J Bone Joint Surg Am. 1952;34(1):129-134.
15
FIGURE LEGENDS Figure 1. Preparation of the joint with intra-medullary holes in the base of the proximal phalanx and the metatarsal head.
16
Figure 2. Structural iliac crest bone graft prepared in a dowel shape of the required size and contoured to fit into the intramedullary holes
17
Figure 3. Dowel bone graft inserted in the MTPJ and evidence of the lengthening achieved.
18
Figure 4. Low-profile plate inserted for internal fixation and the remaining gap that is packed with cancellous bone graft.
19
Figure 5. A. Pre-operative radiographs of failed first and second metatarsophalangeal joint (MTPJ) hemiarthroplasties. B. Post-operative radiographs 16 weeks following dowel revision first MTPJ arthrodesis and second MTPJ Stainsby procedure.
20
TABLE 1. Patients demographics and clinical data. FU: Follow-up (in months), RA: Rheumatoid arthritis, BMI: Body mass index. Case
Age/Sex
FU
1
60 / ♀
102
2 3 4
45 / ♀ 55 / ♀ 65 / ♀
38 40 40
5 6
80 / ♀ 55 / ♂
37 12
7
62 / ♀
12
8
62 / ♀
18
Mean
60.5
37.4
Primary Procedure Keller Non-union Silastic Hemiarthroplasty Proximal phalanx Non-union Non-union after malunion revision Keller
Hemiarthroplasty Metatarsal
Comorbidities RA
Concurrent treatment 2nd toe Stainsby
Complications
Unremitting pain Removal of plate BMI 32
2nd toe fusion
PIPJ
BMI 35 Prominent plate, temporary numbness Polycythemia vera
2nd toe Stainsby+PIPJ fusion, 3rd toe PIPJ fusion Revision of 2nd toe hemiarthroplasty to Stainsby
21
Table 2. Radiographic parameters. HVA: Hallux valgus angle, LOH: Length of hallux, Diff: Difference, SD: Standard deviation. Grey fields are patients in the arthroplasty subgroup (hemiarthroplasty, sylastic arthroplasty). White fields are those patients in the nonarthroplasty subgroup (fusion, Keller arthroplasty). When these two subgroups were compared, the difference of means in HVA was p>0.05 and the difference of means in LOH was p=0.025 (statistically significant). Case 1 2 3 4 5 6 7 8 Mean (SD)
Pre HVA 21 20 18 21 22 19 25 25 21.4 (2.6)
Post HVA 12 10 11 7 15 8 15 15 11.6 (3.2)
Diff HVA -11 -10 -7 -4 -7 -7 -10 -10 -8.2 (2.4)
Pre LOH 82 82 88 85 66 90 77 87 82.1 (7.7)
Post LOH 87 88 89 88 70 97 86 89 86.8 (7.6)
Diff LOH -5 -6 -1 -3 -4 -7 -9 -2 -4.6 (2.7)
22