Background
Upper extremity fractures ipsilateral to an arteriovenous fistula (AVF) in hemodialysis patients are not rare [
1]. Surgical treatment options are still challenging and controversial because of the danger of hypervascularity, hemorrhaging, contraindications of using a pneumatic tourniquet [
1], remodeled anatomy after shunt creation, and the potential effects of the type of treatment on the function of arteriovenous shunts. Only few case series have reported the clinical outcomes of surgical repair for distal radial fracture (DRF) ipsilateral to an AVF [
1,
2].
In our clinical practice, in addition to cast fixation, surgical repairs—volar locking plate fixation (VLPF) and external skeletal fixation (ESF)—are also feasible treatment options. Our search of the literature showed that no published study has compared the effects of VLPF, cast fixation, or ESF on ipsilateral AVF function. Therefore, we evaluated the effects of VLPF, cast fixation, and ESF on ipsilateral AVF function and clinical outcomes. We hypothesized that none of these treatments would affect the AVF function after the AVF had been carefully identified and the fracture was carefully managed before and during the procedure. We also hypothesized that surgical treatment would provide better clinical and radiographic outcomes in this population.
Discussion
This is the first study to compare functional and radiographic outcomes in different treatments of DRFs ipsilateral to AVFs. All DRFs in our study were intraarticular, and all AVFs were preserved and provided adequate hemodialysis at 1 year after the index procedure. At 1-year follow-up, the surgical fixation groups (ESF and VLPF) had better functional (Mayo score and QuickDASH score) and all radiographic (RH, RI, VT, UV, and SO) outcomes than did the cast fixation group. Furthermore, VLPF had better QuickDASH scores and radiographic RI and UV than did the ESF group.
A DRF ipsilateral to an AVF is not rare, but there are scant studies on this condition. There are several treatment choices for managing a DRF, including cast fixation, ESF, and VLPF [
9]. When managing a DRF ipsilateral to an AVF, most patients and surgeons hesitate to use surgical intervention because of the dangers of hypervascularity, hemorrhaging, and contraindications to using a pneumatic tourniquet [
1]. Therefore, closed reduction with cast fixation and an open window for hemodialysis became an alternative treatment. However, the fracture pattern in this population is usually intraarticular and unstable [
10] (in our series 13/13), because of osteomalacia and hemodialysis-related osteoporosis. In our cast fixation group, even acceptable reduction [
3] was achieved after close reduction in the initial attempt, and it is difficult to maintain the reduction during the follow-up. Another possible reason is that the hemodialysis window in the cast diminishes the effect of cast fixation. Other possibilities are pressure ulcers, compartment syndrome, dermatitis, and joint contracture caused by cast fixation [
11]. Therefore, surgical fixation is becoming more popular. Sugiyama et al. [
2] reported that three patients with a DRF ipsilateral to an AVF who underwent VLPF using the Henry approach had satisfactory alignment without shunt complications. Ishiguro et al. [
1] reported that one patient with a Colles’ fracture ipsilateral to an AVF who underwent cement-assisted balloon osteoplasty had a satisfactory outcome without shunt complications.
In our series, the surgical fixation group showed better final radiographic RH, RI, VT, UV, and SO findings than did the cast fixation group, which is consistent with studies that showed better radiographic outcomes in the elderly using surgical intervention rather than cast fixation, the conservative treatment [
12,
13]. Even if the acceptable reduction [
3] could be achieved in the initial reduction in the cast fixation group, the surgical fixation group still showed better immediately postoperative radiographic RI and SO. Correspondingly, at the final 1-year follow-up, the cast fixation group also showed significantly worse functional outcomes: Mayo score and
QuickDASH score. Our results are inconsistent with the study that reported no differences in functional outcomes cast and surgical fixation [
14]. Therefore, according to our findings, surgical fixation should be considered in an unstable DRF [
10] ipsilateral to an AVF, even with the initial acceptable reduction.
In our study, surgical fixation did not affect AVF function, which supports the findings of the previous study [
2]. Furthermore, VLPF provided better UV radiographic outcome immediately after surgery, better RI and UV at the 1-year follow-up, and better
QuickDASH scores at the 1-year follow-up than did ESF. There were no differences in the VAS or Mayo scores between the ESF and VLPF groups at the 1-year follow-up. In the general population, recent meta-analyses have reported better specific radiographic and functional outcomes and a faster recovery with VLPF than with ESF [
15,
16]. In an elderly population, compared with ESF, VLPF provided earlier functional recovery [
17,
18], better restoration of palmar tilt, and better VAS, wrist function, and DASH scores after the final follow-up [
19]. Therefore, VLPF might be a better fixation choice than ESF for hemodialysis patients with DRFs and ipsilateral AVFs. However, hemodialysis patients usually spend a considerable amount of money on hemodialysis. ESF might be an alternative if patients with an unstable DRF cannot afford VLPF treatment cost.
Up to date, there is no study addressing the relationship between the tourniquet time and the possible complications on AVFs, including thrombosis formation and further stenosis. Even though Naito et al. [
20] reported no complication of AVFs following carpal tunnel release using a pneumatic tourniquet in patients with chronic renal dialysis, the application of tourniquet in patients with DRFs and ipsilateral AVFs is still a concern. Therefore, hemorrhaging might be expected because of uremic platelet dysfunction, especially when a tourniquet was not used, but hemorrhages can be controlled using adequate electrocoagulation. Furthermore, shunt and the pulsation of the radial artery that are very easy to be palpated in the absence of tourniquet could be safely checked during the surgery, especially in the application of K-wires or Schanz screws. Hence, we suggest meticulous hemostasis without application of tourniquet in patients with DRFs and ipsilateral AVFs. The radial artery runs between the brachioradialis and flexor radialis tendons. The modified Henry approach that avoids the identification of the radial artery may avoid the potential injury of the radial artery. The AVF is usually more on the radial side of the forearm than is the radial artery. Sugiyama et al reported three patients with DRFs ipsilateral to AVFs treated with volar locking plate fixation via the Henry approach achieved good result and no shunt dysfunction [
2]. According to our results, there is no AVF complication in all four cases undergoing VLPF using a modified Henry approach. Both the Henry and the modified Henry approach may be safe for VLPF in patients with DRFs and ipsilateral AVFs. The reduction techniques used in our cases—provisional K-wire fixation, radial styloid pinning through the snuffbox approximately to the radiocephalic fistula, and the Kapandji technique—were safe for blood vessels monitored using a C-arm fluoroscope and palpable thrill. In addition, anatomical remodeling after shunt creation should also be considered. For ESF and VLPF, overshooting of drilling or longer screw position to the dorsal-radial side is dangerous and should be avoided. For ESF, we practiced predrilling through the sleeve to protect soft tissue and using self-drilling Schanz screws, which should be inserted directly to the bone with gentle retraction around the tissue to ensure that no vessel will be damaged.
Diminishment and failure of AVFs were the most concerned issues during postoperative care in patients with AVFs following ipsilateral surgical interventions. Up to date, there is no literature reporting postoperative complications of AVFs in such population. Some most common complication of AVFs had been mentioned in some literatures and could probably be as a reference for postoperative care [
21‐
23]. Thrombosis is one of the crucial causes for the loss of function of an AVF. The clinical feature of thrombosis included severe pain at the site of thrombosis, palpation of thrombus at the AVF site, tremors, and absence of feeling [
23]. In addition, AVF infection may be manifested as local signs of infection (calor, dolor, and rubor) [
23]. Hence, in addition to general postoperative care of distal radial fracture, the appearance and auscultation of an AVF and the related hemodialysis condition should be closely observed after the index procedure.
Limitations
This study has some limitations. First, our study population is small after excluding patients with incomplete records. However, the differences between our comparison groups were significant, which suggests that the number of patients is adequate to test our hypothesis. Second, a treatment selection bias existed depending upon the attending surgeon, patient selection, and the patient’s economic status. Third, we used QuickDASH and the Mayo wrist score as functional scores to assess the hemodialysis hand—usually the non-dominant hand. Many activities might be compensated by the dominant or healthy hand, which would lead to a score assessment bias. However, there are no specific or modified standard methods for assessing AVF hand function.