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Vascular Injuries After Total Joint Arthroplasty
The Journal of Arthroplasty Vol. 23 No. 8 2008
Vascular Injuries After Total Joint Arthroplasty Javad Parvizi, MD, FRCS, Luis Pulido, MD, Nicholas Slenker, MD, Margaret Macgibeny, BS, James J. Purtill, MD, and Richard H. Rothman, MD, PhD
Abstract: Vascular injuries, although highly feared, can occur after total joint arthroplasty, often resulting in legal suits. This study evaluates the circumstances related to vascular injuries after joint arthroplasty. Using prospectively collected data on 13 517 patients undergoing total joint arthroplasty at our institution, 16 (0.1%) vascular injuries were identified. Eleven injuries occurred after total knee arthroplasty (TKA) and 5 after total hip arthroplasty (THA). Indirect injury was the most common mechanism in TKA. In contrast, direct injury was most prevalent in THA. One patient died of complications related to vascular injury. Of 16 patients, 8 (50%) had launched a legal suit against the operating surgeon. There appears to be no further specific measure that can be taken to absolutely avoid this complication. Patient awareness regarding this real problem may play a role in defraying the high likelihood of legal suits associated with this complication. Key words: arthroplasty, hip, knee, complications, postoperative, intraoperative, vascular. © 2008 Elsevier Inc. All rights reserved.
Total joint arthroplasty (TJA) is a successful procedure that imparts pain relief and better quality of life for patients affected by arthritis of the hip and knee. Because of its resounding success, TJA is now being performed in a broader category of patients, some with preexistent comorbidities [1-3]. The availability of high volume-specialized joint centers [4], and the continuous advances in perioperative care and surgical technique have contributed to a reduction in postoperative morbidity and mortality [5]. Although TJA is considered a safe elective surgery, serious and sometimes fatal complications do occur [6-8]. Although rare, vascular injury is one such complication that can compromise the outcome of TJA [9-14]. The incidence of vascular injury
after TJA is reported to be around 0.2% [15-17]. The risk of vascular problems is reported to be higher in patients with preexistent vascular insufficiency as exhibited by leg claudication, atherosclerosis, prior coronary bypass surgery, and decreased distal pulses [15,18-20]. Vascular injuries after TJA, however, can occur in patients with unrecognized or undetected preoperative vascular problems. Hence, implementation of various strategies, such as conducting detailed preoperative evaluation for the presence of vascular insufficiency, are likely to reduce to the incidence of vascular problems after TJA [15,19]. The main question that remains is how one could avoid vascular injuries during TJA and what strategy could improve the outcome of this complication once it occurs. Previous studies have shown that indirect vessel injury is the most common mechanism for vascular injury during TJA [9,15]. Mechanical stretching, compression, or thermal injury from cement are some of the mechanisms that lead to this problem [9,15,21,22]. Joint arthroplasty, by nature, involves application of mechanical forces that may lead to stretching or compression of vascular structures. Hence, eliminating vascular injuries completely appears counterintuitive.
From the Rothman Institute of Orthopedics at Thomas Jefferson University, Philadelphia, Pennsylvania. Submitted October 2, 2007; accepted February 18, 2008. Javad Parvizi, MD, FRCS, received funding for his research from Stryker Orthopedics, Mahwah, NJ. Reprint requests: Javad Parvizi, MD, FRCS, Rothman Institute of Orthopedics at Thomas Jefferson Hospital, 925 Chestnut St, Philadelphia, PA 19107. © 2008 Elsevier Inc. All rights reserved. 0883-5403/08/2308-0004$34.00/0 doi:10.1016/j.arth.2008.02.016
1115
1116 The Journal of Arthroplasty Vol. 23 No. 8 December 2008 This study sought to identify the incidence, the nature, and the outcome of vascular injuries from a single high-volume institution with the intention of determining strategies that could have avoided these complications, some of which resulted in legal suits.
Materials and Methods Demographics Using the prospectively collected institutional joint arthroplasty database, patients with vascular injury after TJA were identified. During the period of this study from January 2000 to August 2006, 15 383 hip and knee arthroplasties were performed in 13 517 patients at our institution. There were 5728 men with a mean age of 61 years (range, 15-93 years) and 7789 women with a mean age of 65 years (range, 13-97 years). Preoperative Evaluation All patients undergoing elective arthroplasty received thorough medical evaluation before the index surgery. The examination of the vascular status involved palpation of the distal pulses by the surgeon and the internist as well as referral to a vascular specialist if any problems with the arterial or venous status of the limb were detected. None of the patients sustaining vascular problem in this cohort required preoperative vascular evaluation. Surgical Data Hypotensive regional anesthesia was used for 98% of the patients in this cohort. All operations were performed by or under close supervision of a subspecialized arthroplasty surgeon. Total hip arthroplasties (THAs) were performed in supine position through an anterolateral approach. Total knee arthroplasties (TKAs) were performed under tourniquet using medial parapatellar arthrotomy approach. Uncemented components were used for the hip prostheses, whereas the knee cases used cemented fixation. Total joint arthroplasty surgery has been performed in our specialized joint center for more than 20 years. Between January 1984 and August 2006, a total of 30 753 patients have undergone joint arthroplasty at our institution. Postoperative Course All patients were followed closely, and all identified complications were recorded. Vascular injuries were defined as direct vessel (arterial or venous) laceration or as indirect arterial occlusion (throm-
bosis or embolization). Most vascular injuries were identified in the postoperative recovery unit. Detailed data on the mode of presentation, the type of intervention, and the outcome of the total joint arthroplasty were determined retrospectively. The complications identified were captured from the complication database that is completed for all patients. All patients' discharge summaries were also searched to capture any complications that may have gone undetected.
Results Vascular injuries were identified in 16 patients (0.1%) after TJA (Table 1). Eleven injuries occurred after TKA, including 10 primary TKAs and 1 revision TKA. Five injuries occurred after THA, including 3 primary THAs and 2 revision THAs. The mean age of patients with vascular injury was 66 years (range, 44-86 years). The mean body mass index was 29.7 kg/m2 (range, 23.4-43.4 kg/m2). The mean ASA (Anesthesia Society score) was 3 (range, 2-4). Preexistent comorbidities included hypertension in 69% (11/16 patients), cardiovascular disease in 50% (8/16 patients), history of smoking in 44% (7/16 patients), obesity in 37% (6/16 patients), and diabetes mellitus in 31% (5/16 patients). Presentation of Vascular Injury All vascular injuries associated with TKA were recognized after the completion of surgery. Vascular injuries occurring during hip arthroplasty were recognized intraoperatively in 3 patients, as excessive or pulsatile bleeding, and postoperatively, in 2 patients. Vascular damage was recognized in the immediate postoperative recovery area in 7 patients (44%), at various times during the postoperative recovery (8 patients), and after discharge from the hospital (1 patient). Four patients were diagnosed on postoperative day 1 with decreased or absent pulses after palpation and Doppler evaluation associated with decreased sensation and motor function. Arterial injury presented on postoperative day 4 in one case as intractable thigh pain and a significant drop in hemoglobin level (11.8-5.6 g/dL). One patient with mental disabilities was readmitted to the emergency department 12 days after TKA with severe pain, compartment syndrome, and gangrene of the distal lower extremity. Lack of a distal pulse was the main sign of vascular problem that prompted vascular consult and further investigation in all TKA cases. Angiography was performed in 13 of 16 cases that either confirmed block to arterial flow at various points in the
Vascular Injuries After Total Joint Arthroplasty Parvizi et al
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Table 1. Details of Patients who Sustained a Vascular Injury after TJA Patient
Procedure
Age
Sex
Comorbidities
Hip arthroplasty 1 Primary 2 Revision 3 Revision
53 71 82
F F M
4
Primary
49
F
HTN HTN-smoking Hypercholesterolemia -Smoking -HTN Smoking
5 Primary Knee arthroplasty 6 Primary 7 Primary 8 Primary 9 Primary 10 Primary 11 Primary 12 Primary
44
F
82 72 61 56 60 78 63
F F F F M F F
13
Primary
81
F
14 15
Primary Revision
86 57
F M
16
Primary
67
F
Time of Diagnosis (Postoperative Days)
Management
0 (Intraoperative) 0 (Intraoperative) 0 (Intraoperative)
Bypass graft Surgical repair Surgical repair
Final Outcome
1
Bypass graft
Depression
4
Surgical repair
Not affected Not affected Multiorgan failure -Hypotension -Death Skin necrosis-skin grafting Not affected
HTN-DM-CAD HTN-DM-CAD Anxiety HTN-seizures HTN-CAD HTN Hypercholesterolemia -Mitral valve disease -DM HTN-hypothyroidism
0 0 0 0 0 0 1
Bypass graft Thrombectomy Thrombectomy Angioplasty Nonoperative Angioplasty Bypass graft
Not affected Not affected Peroneal nerve palsy Periprosthetic infection Not affected Not affected Not affected
1
Bypass graft
None DM-depression -Hypothyroidism HTN-DM-CAD -Chronic renal failure -Multiple myeloma
1 1
Angioplasty Nonoperative
Skin necrosis-skin grafting Not affected Not affected
12
Bypass graft
Gangrene -Amputation
HTN indicates hypertension; DM, diabetes mellitus; CAD, coronary artery disease, M, male; F, female.
popliteal arterial system (11 patients) or bleeding from vasculature around the hip (1 patient). The most common complaint by the patient during the early postoperative period was pain and swelling. Physical evaluation of the affected extremity showed pallor, cold extremity, decreased or absent pulses, and decreased capillary refill. Etiology Popliteal artery thrombosis was the most common cause for arterial injury after TKA (82%; 9/11). Indirect damage was thought to be the mechanism for arterial injury in most patients. Two patients undergoing TKA had a direct injury to the popliteal artery that was likely caused by a penetrating instrument. This resulted in a popliteal artery laceration and eventual thrombosis that were discovered the first day after surgery. In contrast, direct arterial laceration was the most common mechanism of injury during THA (4/5). Three femoral artery lacerations and 1 external iliac artery laceration were diagnosed. The latter was a complex hip revision surgery, and it occurred while resecting a cemented acetabular cup in patient with marked pelvic discontinuity. Two other patients had femoral artery thrombosis.
Treatment The vascular surgery consult was sought immediately after recognition of a vascular problem in all patients. Definitive diagnosis was achieved with angiography in 13 of the 16 cases. The other vascular injuries were recognized intraoperatively and visualized without a need for angiography. The management of arterial injuries after TKA included direct popliteal thrombectomy (2/11), popliteal artery bypass graft (4/11), angioplasty (3/11), and nonoperative treatment (2/11). Direct vascular repair was instituted for 3 THA patients in whom vascular injury was recognized intraoperatively. One of these patients with damage to the external iliac vessel required an end-to-end anastomosis. The other 2 patients sustained femoral artery lacerations that were repaired directly in one case and with an iliofemoral bypass graft in the other. Two other patients undergoing THA developed femoral artery thrombosis that was repaired by iliofemoral bypass in the early postoperative period. Outcome Most patients in this cohort (76%; 13/16 patients) had full restoration of neurovascular function of the
1118 The Journal of Arthroplasty Vol. 23 No. 8 December 2008 affected limb at the time of discharge. One patient had persistent peroneal nerve palsy and an associated foot drop. Four compartment fasciotomy was performed in 8 of the 16 patients for suspected compartment syndrome, 5 after TKA, and 3 after THA. The management of fasciotomy included wound inspection 2 days after fasciotomy and closure of the wound within 5 days of TKA either directly or with the use of skin graft. One patient who had undergone fasciotomy after TKA developed skin necrosis and subsequent periprosthetic infection that was treated successfully by irrigation and debridement of the knee joint and retention of the prosthesis. There was one death in the cohort. This patient, who had direct external iliac vessel laceration during THA, required massive transfusion and developed multiorgan failure 2 days after the index surgery. Above-the-knee amputation was performed in one patient with popliteal artery thrombosis with failed bypass. This patient had extensive medical history that included mental disability, hypertension, diabetes mellitus, chronic renal failure, and multiple myeloma. This patient was readmitted to the hospital 12 days after TKA with ischemic necrosis and compartment syndrome of the left lower extremity. Initially, a 4-compartment fasciotomy and popliteal artery bypass graft was done. Adequate revitalization of the ischemic tissue was unsuccessful. Liability Arterial injury after TJA was associated with a high likelihood of a legal suit. Of 16 patients, 8 (50%) had launched a legal suit against the operating surgeon. The lawsuit was launched at a mean of 1.4 months (range, 0.2-11 months) after the injury. One of the law suits resulted in a settlement payment, 1 was dismissed by the judge, 1 case was won by the defendant, and the other 5 cases are still pending.
Discussion Modern TJA is a successful and safe surgery; however, vascular complications may occur with potential for limb and life-threatening consequences [8,15,19,23]. The incidence of vascular injury after TJA is fortunately rare and estimated to be around 0.2% [15,22]. The estimated prevalence in the literature is reported to be around 0.25% [13,16,20]. However, as more joint arthroplasties are being performed each year, the number of this potentially devastating complication will increase
[24]. It has also been reported that the incidence of vascular injury may be rising, as a higher number of complex revision procedures are being performed each year [18]. The uncertainty that remains is why vascular injuries occur during TJA and whether the strategies currently being implemented are enough to avoid them. Although ideal, the complete prevention of vascular injuries after any surgical procedure including TJA is clearly not feasible. Intuitively, vascular injury will occur in cases such as surgical dissection in patients with aberrant anatomy, irrespective of the degree of skill and the prudence of the surgeon. Therefore, the main objective of this study was to identify factors that could help reduce the incidence of this complication. We found that almost all vascular injuries occurring during TKA result from indirect trauma, whereas all injuries occurring during THA are direct vessel injuries. This finding is in agreement with previous studies reporting similar mechanisms and relates to the specifics of the procedure [9,13,16,21,22,25]. Dislocation of the knee joint in some patients requires excessive forces that need to be placed behind the tibia. It is easy to comprehend why this maneuver could result in stretching of the popliteal vessels and subsequent injury. Hip arthroplasty necessitates placement of retractors around the acetabulum, in the vicinity of extensive vasculature, which could lead to tear of the vessels. Direct vessel injury during THA can occur also as a result of placement of supplemental screw fixation of the acetabular component [25,26]. Previous studies have defined safe zones for placement of screws in the acetabular component [26]. One may therefore conclude that appropriate placement of retractors and screws and minimization of the forces applied for dislocation of the knee may “prevent” vascular complications. Although the aforementioned are good surgical principles, the situation is unfortunately never that simple. In cases such as a challenging revision THA, the need for placement of multiple supplemental screws may lead to vessel injury. Furthermore, patients with severe knee contracture, aberrant vascular anatomy, and those with preexisting vessel disease and calcification abound. The next challenge identified by this study is recognition of vascular complications, which can be difficult in some patients. Because of the use of tourniquet during surgery and indirect injury is frequently the mechanism of injury, recognition of vascular injuries during TKA is almost always in the postoperative period. Furthermore, the use of regional anesthesia that affects the neurologic
Vascular Injuries After Total Joint Arthroplasty Parvizi et al
status of the limb can delay the recognition of vascular complications. On the basis of the findings of this study, we have implemented a protocol in our institution that requires vascular check by the postanesthesia recovery unit personnel and/or the residents for all patients before disposition to the wards. We do, of course, recognize that vascular injury is not always the cause of pulseless extremity. Loss of pulse may relate to reversible arterial spasm, tight dressing, or may be seen in a patient with absent pulses from preoperative period. Hence, a detailed protocol has also been implemented at the postanesthesia recovery unit that involves release of the dressing and monitoring of the patient. If pulse fails to return within a short period (ie, minutes) or cannot be picked up by Doppler, then emergent vascular consult is sought. The aforementioned protocols, however, may not be applicable or implementable in every institution. Many medical institutions lack resources such as emergent vascular service, which makes execution of said protocols impossible. An additional problem this study has identified is that not every vascular injury manifests during the early postoperative period and some may have a rapid deterioration course. There were a few patients in our cohort, who despite having a palpable pulse in the immediate postoperative period, exhibited vascular insufficiency at a later period. One patient presented on postoperative day 12 with an acute ischemia and a necrotic limb. The latter case highlights the importance of keeping a high index of suspicion for this complication. Any patient with extensive limb swelling, ongoing pain, and an incalcitrant postoperative course should be examined in person. Although these symptoms and signs may relate more to development of a deep venous thrombosis than an arterial injury, diligent monitoring of these patients is critical to avoid adverse outcome. All vascular problems in this cohort were arterial in nature. Injuries to veins can and do occur after TJA [12]. Venous injuries, however, may be more benign in course and, if minor, may escape detection. It is plausible that some patients in our large cohort may have experienced venous injuries that were not identified. Most venous injuries occur during placement of acetabular screws. Although none was identified in this cohort, we believe that at least one of the THA patients had an associated vein injury. Angiography is an extremely useful tool for diagnosis and confirmation of vascular injury. However, angiography should, in our opinion, be performed in a dedicated vascular suite and by a
1119
vascular expert to facilitate prompt treatment. A large number of patients with acute arterial thrombosis in this cohort could be treated by direct thrombectomy and cryotherapy successfully. Again, we realize that many institutions may lack such facilities. It is nonetheless crucial that intervention and revascularization can be carried out as soon as circumstances allow as the success of treatment is highly time dependent. A warm ischemia time interval of less than 6 hours is generally the accepted period within which arterial continuity must be restored to avoid permanent soft tissue damage [27]. Despite all the mentioned findings, the main question of the study still remains unanswered. Despite evaluating every possible parameter, it is difficult to determine if anything could have been done to prevent the vascular complications in this cohort or in general. All 16 patients in this cohort had documented palpable pulse preoperatively. Appropriate pressure (b350 mm Hg) and duration (b90 minutes) of tourniquet were used in the TKA cohort. All instruments used to expose the acetabulum were blunt and positioned with caution. Placement of screw was not the cause of any of the vascular injuries during THA. Intervention, in the form of revascularization, was implemented within a very short period of recognition or confirmation of the vascular injury. The one “inconsistent” issue in these patients related to compartment releases. Some patients did receive compartment release, and some did not “need” fasciotomy. The course of action was determined based on clinical decision. One of the major problems related to measurement of compartment pressure is that “normal” pressures in the compartments after TJA is not known. All the literature on compartment pressures is based on acute trauma models and is not applicable to TJA patients. Furthermore, the tendency to err on the side of caution and perform compartment release, besides the inconvenience of subjecting the patient to multiple additional surgeries, could result in an adverse outcome in patients with artificial joint as was seen in one patient in this series who developed periprosthetic infection. The other challenge identified during this study, patients whose vascular problem was identified at a later time point, calls us to question whether this was a result of late diagnosis or manifestation of the disease. The evaluation of medical records of every patient with late presentation revealed that a palpable pulse was documented in the immediate postoperative recovery and every morning during the hospital stay. Hence, lack of attention to the
1120 The Journal of Arthroplasty Vol. 23 No. 8 December 2008 vascular status did not seem to be the cause of late diagnosis. It appears that arterial occlusion, though exceedingly rare, can occur any time after TJA. In retrospect, one may argue that more diligent attention to the patient with delayed presentation (12 days postsurgery) may have prevented the need for amputation. Unfortunately, the lack of attention to the problem by the patient and delay in seeking medical advice was a large contributing factor in this particular case. On the basis of the findings of this study, we now ensure that important complications including arterial thrombosis, in spite of its extremely rare incidence, are discussed with the patients before discharge from the hospital. Nearly one half of the patients in our cohort elected to launch a legal suit against the operating surgeon. It is apparent from this patient series that there is a high likelihood of legal suits associated with orthopedic vascular complications. Surgical mishaps, misdiagnoses, improper treatments, and failure to diagnose are the leading cause of malpractice claims [28]. We were unable to identify any evidence for error in surgical practice or delivery of appropriate intervention in these patients. Furthermore, all patients had been informed regarding the potential of vascular complications before surgery. We heed the advice of a recent study on 2288 patients and 103 orthopedic surgeons that suggests that physicians who establish a rapport with the patient and explain the injury and treatment plan more effectively experience fewer subsequent malpractice claims [29,30]. It appears that despite all efforts to prevent or minimize risk, vascular complications after joint arthroplasty will continue to occur. Although vascular complications after TJA are exceedingly rare, the consequences are severe enough to necessitate a conversation with the patient before the operation. Patient awareness regarding this problem may then play a role in defraying the high likelihood of legal suits associated with this complication.
5.
6.
7.
8.
9.
10.
11.
12.
13. 14.
15.
16.
17.
18.
19.
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the outcomes of total knee replacement. J Bone Joint Surg Am 2004;86-A:1909. Parvizi J, Holiday AD, Ereth MH, et al. The Frank Stinchfield Award. Sudden death during primary hip arthroplasty. Clin Orthop Relat Res 1999;369:39. Mahomed NN, Barrett J, Katz JN, et al. Epidemiology of total knee replacement in the United States Medicare population. J Bone Joint Surg Am 2005;87:1222. Parvizi J, Johnson BG, Rowland C, et al. Thirty-day mortality after elective total hip arthroplasty. J Bone Joint Surg Am 2001;83-A:1524. Parvizi J, Mui A, Purtill JJ, et al. Total joint arthroplasty: when do fatal or near-fatal complications occur? J Bone Joint Surg Am 2007;89:27. Aust JC, Bredenberg CE, Murray DG. Mechanisms of arterial injuries associated with total hip replacement. Arch Surg 1981;116:345. Berger C, Anzbock W, Lange A, et al. Arterial occlusion after total knee arthroplasty: successful management of an uncommon complication by percutaneous thrombus aspiration. J Arthroplasty 2002;17:227. Calligaro KD, Delaurentis DA, Booth RE, et al. Acute arterial thrombosis associated with total knee arthroplasty. J Vasc Surg 1994;20:927. Doi S, Motoyama Y, Itoh H. External iliac vein injury during total hip arthroplasty resulting in delayed shock. Br J Anaesth 2005;94:866. Lewallen DG. Neurovascular injury associated with hip arthroplasty. Instr Course Lect 1998;47:275. Shoenfeld NA, Stuchin SA, Pearl R, et al. The management of vascular injuries associated with total hip arthroplasty. J Vasc Surg 1990;11:549. Calligaro KD, Dougherty MJ, Ryan S, et al. Acute arterial complications associated with total hip and knee arthroplasty. J Vasc Surg 2003;38:1170. Nachbur B, Meyer RP, Verkkala K, et al. The mechanisms of severe arterial injury in surgery of the hip joint. Clin Orthop Relat Res 1979;141:122. Rand JA. Vascular complications of total knee arthroplasty. Report of three cases. J Arthroplasty 1987;2:89. Barrack RL, Butler RA. Avoidance and management of neurovascular injuries in total hip arthroplasty. Instr Course Lect 2003;52:267. Barrack RL. Neurovascular injury: avoiding catastrophe. J Arthroplasty 2004;19(4 Suppl 1):104. Smith DE, McGraw RW, Taylor DC, et al. Arterial complications and total knee arthroplasty. J Am Acad Orthop Surg 2001;9:253. Hirsch SA, Robertson H, Gorniowsky M. Arterial occlusion secondary to methylmethacrylate use. Arch Surg 1976;111:204. Kumar SN, Chapman JA, Rawlins I. Vascular injuries in total knee arthroplasty. A review of the problem with special reference to the possible effects of the tourniquet. J Arthroplasty 1998;13:211. Bergqvist D, Carlsson AS, Ericsson BF. Vascular complications after total hip arthroplasty. Acta Orthop Scand 1983;54:157.
Vascular Injuries After Total Joint Arthroplasty Parvizi et al 24. Rue JP, Inoue N, Mont MA. Current overview of neurovascular structures in hip arthroplasty: anatomy, preoperative evaluation, approaches, and operative techniques to avoid complications. Orthopedics 2004;27:73. 25. Keating EM, Ritter MA, Faris PM. Structures at risk from medially placed acetabular screws. J Bone Joint Surg Am 1990;72:509. 26. Wasielewski RC, Cooperstein LA, Kruger MP, et al. Acetabular anatomy and the transacetabular fixation of screws in total hip arthroplasty. J Bone Joint Surg Am 1990;72:501.
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27. Graves M, Cole PA. Diagnosis of peripheral vascular injury in extremity trauma. Orthopedics 2006;29:35. 28. Fountain S, Brooks D, Butler D, et al. Managing orthopaedic malpractice risk: Committee on Professional Liability. Rosemont, IL; American Academy of Orthopaedic Surgeons 2000;3. 29. Adamson TE, Bunch WH, Baldwin Jr DC, et al. The virtuous orthopaedist has fewer malpractice suits. Clin Orthop Relat Res 2000;378:104. 30. Adamson TE, Baldwin Jr DC, Sheehan TJ, et al. Characteristics of surgeons with high and low malpractice claims rates. West J Med 1997;166:37.
Vascular Injuries After Total Joint Arthroplasty Javad Parvizi, MD, FRCS, Luis Pulido, MD, Nicholas Slenker, MD, Margaret Macgibeny, BS, James J. Purtill, MD, and Richard H. Rothman, MD, PhD
Abstract: Vascular injuries, although highly feared, can occur after total joint arthroplasty, often resulting in legal suits. This study evaluates the circumstances related to vascular injuries after joint arthroplasty. Using prospectively collected data on 13 517 patients undergoing total joint arthroplasty at our institution, 16 (0.1%) vascular injuries were identified. Eleven injuries occurred after total knee arthroplasty (TKA) and 5 after total hip arthroplasty (THA). Indirect injury was the most common mechanism in TKA. In contrast, direct injury was most prevalent in THA. One patient died of complications related to vascular injury. Of 16 patients, 8 (50%) had launched a legal suit against the operating surgeon. There appears to be no further specific measure that can be taken to absolutely avoid this complication. Patient awareness regarding this real problem may play a role in defraying the high likelihood of legal suits associated with this complication. Key words: arthroplasty, hip, knee, complications, postoperative, intraoperative, vascular. © 2008 Elsevier Inc. All rights reserved.
Total joint arthroplasty (TJA) is a successful procedure that imparts pain relief and better quality of life for patients affected by arthritis of the hip and knee. Because of its resounding success, TJA is now being performed in a broader category of patients, some with preexistent comorbidities [1-3]. The availability of high volume-specialized joint centers [4], and the continuous advances in perioperative care and surgical technique have contributed to a reduction in postoperative morbidity and mortality [5]. Although TJA is considered a safe elective surgery, serious and sometimes fatal complications do occur [6-8]. Although rare, vascular injury is one such complication that can compromise the outcome of TJA [9-14]. The incidence of vascular injury
after TJA is reported to be around 0.2% [15-17]. The risk of vascular problems is reported to be higher in patients with preexistent vascular insufficiency as exhibited by leg claudication, atherosclerosis, prior coronary bypass surgery, and decreased distal pulses [15,18-20]. Vascular injuries after TJA, however, can occur in patients with unrecognized or undetected preoperative vascular problems. Hence, implementation of various strategies, such as conducting detailed preoperative evaluation for the presence of vascular insufficiency, are likely to reduce to the incidence of vascular problems after TJA [15,19]. The main question that remains is how one could avoid vascular injuries during TJA and what strategy could improve the outcome of this complication once it occurs. Previous studies have shown that indirect vessel injury is the most common mechanism for vascular injury during TJA [9,15]. Mechanical stretching, compression, or thermal injury from cement are some of the mechanisms that lead to this problem [9,15,21,22]. Joint arthroplasty, by nature, involves application of mechanical forces that may lead to stretching or compression of vascular structures. Hence, eliminating vascular injuries completely appears counterintuitive.
From the Rothman Institute of Orthopedics at Thomas Jefferson University, Philadelphia, Pennsylvania. Submitted October 2, 2007; accepted February 18, 2008. Javad Parvizi, MD, FRCS, received funding for his research from Stryker Orthopedics, Mahwah, NJ. Reprint requests: Javad Parvizi, MD, FRCS, Rothman Institute of Orthopedics at Thomas Jefferson Hospital, 925 Chestnut St, Philadelphia, PA 19107. © 2008 Elsevier Inc. All rights reserved. 0883-5403/08/2308-0004$34.00/0 doi:10.1016/j.arth.2008.02.016
1115
1116 The Journal of Arthroplasty Vol. 23 No. 8 December 2008 This study sought to identify the incidence, the nature, and the outcome of vascular injuries from a single high-volume institution with the intention of determining strategies that could have avoided these complications, some of which resulted in legal suits.
Materials and Methods Demographics Using the prospectively collected institutional joint arthroplasty database, patients with vascular injury after TJA were identified. During the period of this study from January 2000 to August 2006, 15 383 hip and knee arthroplasties were performed in 13 517 patients at our institution. There were 5728 men with a mean age of 61 years (range, 15-93 years) and 7789 women with a mean age of 65 years (range, 13-97 years). Preoperative Evaluation All patients undergoing elective arthroplasty received thorough medical evaluation before the index surgery. The examination of the vascular status involved palpation of the distal pulses by the surgeon and the internist as well as referral to a vascular specialist if any problems with the arterial or venous status of the limb were detected. None of the patients sustaining vascular problem in this cohort required preoperative vascular evaluation. Surgical Data Hypotensive regional anesthesia was used for 98% of the patients in this cohort. All operations were performed by or under close supervision of a subspecialized arthroplasty surgeon. Total hip arthroplasties (THAs) were performed in supine position through an anterolateral approach. Total knee arthroplasties (TKAs) were performed under tourniquet using medial parapatellar arthrotomy approach. Uncemented components were used for the hip prostheses, whereas the knee cases used cemented fixation. Total joint arthroplasty surgery has been performed in our specialized joint center for more than 20 years. Between January 1984 and August 2006, a total of 30 753 patients have undergone joint arthroplasty at our institution. Postoperative Course All patients were followed closely, and all identified complications were recorded. Vascular injuries were defined as direct vessel (arterial or venous) laceration or as indirect arterial occlusion (throm-
bosis or embolization). Most vascular injuries were identified in the postoperative recovery unit. Detailed data on the mode of presentation, the type of intervention, and the outcome of the total joint arthroplasty were determined retrospectively. The complications identified were captured from the complication database that is completed for all patients. All patients' discharge summaries were also searched to capture any complications that may have gone undetected.
Results Vascular injuries were identified in 16 patients (0.1%) after TJA (Table 1). Eleven injuries occurred after TKA, including 10 primary TKAs and 1 revision TKA. Five injuries occurred after THA, including 3 primary THAs and 2 revision THAs. The mean age of patients with vascular injury was 66 years (range, 44-86 years). The mean body mass index was 29.7 kg/m2 (range, 23.4-43.4 kg/m2). The mean ASA (Anesthesia Society score) was 3 (range, 2-4). Preexistent comorbidities included hypertension in 69% (11/16 patients), cardiovascular disease in 50% (8/16 patients), history of smoking in 44% (7/16 patients), obesity in 37% (6/16 patients), and diabetes mellitus in 31% (5/16 patients). Presentation of Vascular Injury All vascular injuries associated with TKA were recognized after the completion of surgery. Vascular injuries occurring during hip arthroplasty were recognized intraoperatively in 3 patients, as excessive or pulsatile bleeding, and postoperatively, in 2 patients. Vascular damage was recognized in the immediate postoperative recovery area in 7 patients (44%), at various times during the postoperative recovery (8 patients), and after discharge from the hospital (1 patient). Four patients were diagnosed on postoperative day 1 with decreased or absent pulses after palpation and Doppler evaluation associated with decreased sensation and motor function. Arterial injury presented on postoperative day 4 in one case as intractable thigh pain and a significant drop in hemoglobin level (11.8-5.6 g/dL). One patient with mental disabilities was readmitted to the emergency department 12 days after TKA with severe pain, compartment syndrome, and gangrene of the distal lower extremity. Lack of a distal pulse was the main sign of vascular problem that prompted vascular consult and further investigation in all TKA cases. Angiography was performed in 13 of 16 cases that either confirmed block to arterial flow at various points in the
Vascular Injuries After Total Joint Arthroplasty Parvizi et al
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Table 1. Details of Patients who Sustained a Vascular Injury after TJA Patient
Procedure
Age
Sex
Comorbidities
Hip arthroplasty 1 Primary 2 Revision 3 Revision
53 71 82
F F M
4
Primary
49
F
HTN HTN-smoking Hypercholesterolemia -Smoking -HTN Smoking
5 Primary Knee arthroplasty 6 Primary 7 Primary 8 Primary 9 Primary 10 Primary 11 Primary 12 Primary
44
F
82 72 61 56 60 78 63
F F F F M F F
13
Primary
81
F
14 15
Primary Revision
86 57
F M
16
Primary
67
F
Time of Diagnosis (Postoperative Days)
Management
0 (Intraoperative) 0 (Intraoperative) 0 (Intraoperative)
Bypass graft Surgical repair Surgical repair
Final Outcome
1
Bypass graft
Depression
4
Surgical repair
Not affected Not affected Multiorgan failure -Hypotension -Death Skin necrosis-skin grafting Not affected
HTN-DM-CAD HTN-DM-CAD Anxiety HTN-seizures HTN-CAD HTN Hypercholesterolemia -Mitral valve disease -DM HTN-hypothyroidism
0 0 0 0 0 0 1
Bypass graft Thrombectomy Thrombectomy Angioplasty Nonoperative Angioplasty Bypass graft
Not affected Not affected Peroneal nerve palsy Periprosthetic infection Not affected Not affected Not affected
1
Bypass graft
None DM-depression -Hypothyroidism HTN-DM-CAD -Chronic renal failure -Multiple myeloma
1 1
Angioplasty Nonoperative
Skin necrosis-skin grafting Not affected Not affected
12
Bypass graft
Gangrene -Amputation
HTN indicates hypertension; DM, diabetes mellitus; CAD, coronary artery disease, M, male; F, female.
popliteal arterial system (11 patients) or bleeding from vasculature around the hip (1 patient). The most common complaint by the patient during the early postoperative period was pain and swelling. Physical evaluation of the affected extremity showed pallor, cold extremity, decreased or absent pulses, and decreased capillary refill. Etiology Popliteal artery thrombosis was the most common cause for arterial injury after TKA (82%; 9/11). Indirect damage was thought to be the mechanism for arterial injury in most patients. Two patients undergoing TKA had a direct injury to the popliteal artery that was likely caused by a penetrating instrument. This resulted in a popliteal artery laceration and eventual thrombosis that were discovered the first day after surgery. In contrast, direct arterial laceration was the most common mechanism of injury during THA (4/5). Three femoral artery lacerations and 1 external iliac artery laceration were diagnosed. The latter was a complex hip revision surgery, and it occurred while resecting a cemented acetabular cup in patient with marked pelvic discontinuity. Two other patients had femoral artery thrombosis.
Treatment The vascular surgery consult was sought immediately after recognition of a vascular problem in all patients. Definitive diagnosis was achieved with angiography in 13 of the 16 cases. The other vascular injuries were recognized intraoperatively and visualized without a need for angiography. The management of arterial injuries after TKA included direct popliteal thrombectomy (2/11), popliteal artery bypass graft (4/11), angioplasty (3/11), and nonoperative treatment (2/11). Direct vascular repair was instituted for 3 THA patients in whom vascular injury was recognized intraoperatively. One of these patients with damage to the external iliac vessel required an end-to-end anastomosis. The other 2 patients sustained femoral artery lacerations that were repaired directly in one case and with an iliofemoral bypass graft in the other. Two other patients undergoing THA developed femoral artery thrombosis that was repaired by iliofemoral bypass in the early postoperative period. Outcome Most patients in this cohort (76%; 13/16 patients) had full restoration of neurovascular function of the
1118 The Journal of Arthroplasty Vol. 23 No. 8 December 2008 affected limb at the time of discharge. One patient had persistent peroneal nerve palsy and an associated foot drop. Four compartment fasciotomy was performed in 8 of the 16 patients for suspected compartment syndrome, 5 after TKA, and 3 after THA. The management of fasciotomy included wound inspection 2 days after fasciotomy and closure of the wound within 5 days of TKA either directly or with the use of skin graft. One patient who had undergone fasciotomy after TKA developed skin necrosis and subsequent periprosthetic infection that was treated successfully by irrigation and debridement of the knee joint and retention of the prosthesis. There was one death in the cohort. This patient, who had direct external iliac vessel laceration during THA, required massive transfusion and developed multiorgan failure 2 days after the index surgery. Above-the-knee amputation was performed in one patient with popliteal artery thrombosis with failed bypass. This patient had extensive medical history that included mental disability, hypertension, diabetes mellitus, chronic renal failure, and multiple myeloma. This patient was readmitted to the hospital 12 days after TKA with ischemic necrosis and compartment syndrome of the left lower extremity. Initially, a 4-compartment fasciotomy and popliteal artery bypass graft was done. Adequate revitalization of the ischemic tissue was unsuccessful. Liability Arterial injury after TJA was associated with a high likelihood of a legal suit. Of 16 patients, 8 (50%) had launched a legal suit against the operating surgeon. The lawsuit was launched at a mean of 1.4 months (range, 0.2-11 months) after the injury. One of the law suits resulted in a settlement payment, 1 was dismissed by the judge, 1 case was won by the defendant, and the other 5 cases are still pending.
Discussion Modern TJA is a successful and safe surgery; however, vascular complications may occur with potential for limb and life-threatening consequences [8,15,19,23]. The incidence of vascular injury after TJA is fortunately rare and estimated to be around 0.2% [15,22]. The estimated prevalence in the literature is reported to be around 0.25% [13,16,20]. However, as more joint arthroplasties are being performed each year, the number of this potentially devastating complication will increase
[24]. It has also been reported that the incidence of vascular injury may be rising, as a higher number of complex revision procedures are being performed each year [18]. The uncertainty that remains is why vascular injuries occur during TJA and whether the strategies currently being implemented are enough to avoid them. Although ideal, the complete prevention of vascular injuries after any surgical procedure including TJA is clearly not feasible. Intuitively, vascular injury will occur in cases such as surgical dissection in patients with aberrant anatomy, irrespective of the degree of skill and the prudence of the surgeon. Therefore, the main objective of this study was to identify factors that could help reduce the incidence of this complication. We found that almost all vascular injuries occurring during TKA result from indirect trauma, whereas all injuries occurring during THA are direct vessel injuries. This finding is in agreement with previous studies reporting similar mechanisms and relates to the specifics of the procedure [9,13,16,21,22,25]. Dislocation of the knee joint in some patients requires excessive forces that need to be placed behind the tibia. It is easy to comprehend why this maneuver could result in stretching of the popliteal vessels and subsequent injury. Hip arthroplasty necessitates placement of retractors around the acetabulum, in the vicinity of extensive vasculature, which could lead to tear of the vessels. Direct vessel injury during THA can occur also as a result of placement of supplemental screw fixation of the acetabular component [25,26]. Previous studies have defined safe zones for placement of screws in the acetabular component [26]. One may therefore conclude that appropriate placement of retractors and screws and minimization of the forces applied for dislocation of the knee may “prevent” vascular complications. Although the aforementioned are good surgical principles, the situation is unfortunately never that simple. In cases such as a challenging revision THA, the need for placement of multiple supplemental screws may lead to vessel injury. Furthermore, patients with severe knee contracture, aberrant vascular anatomy, and those with preexisting vessel disease and calcification abound. The next challenge identified by this study is recognition of vascular complications, which can be difficult in some patients. Because of the use of tourniquet during surgery and indirect injury is frequently the mechanism of injury, recognition of vascular injuries during TKA is almost always in the postoperative period. Furthermore, the use of regional anesthesia that affects the neurologic
Vascular Injuries After Total Joint Arthroplasty Parvizi et al
status of the limb can delay the recognition of vascular complications. On the basis of the findings of this study, we have implemented a protocol in our institution that requires vascular check by the postanesthesia recovery unit personnel and/or the residents for all patients before disposition to the wards. We do, of course, recognize that vascular injury is not always the cause of pulseless extremity. Loss of pulse may relate to reversible arterial spasm, tight dressing, or may be seen in a patient with absent pulses from preoperative period. Hence, a detailed protocol has also been implemented at the postanesthesia recovery unit that involves release of the dressing and monitoring of the patient. If pulse fails to return within a short period (ie, minutes) or cannot be picked up by Doppler, then emergent vascular consult is sought. The aforementioned protocols, however, may not be applicable or implementable in every institution. Many medical institutions lack resources such as emergent vascular service, which makes execution of said protocols impossible. An additional problem this study has identified is that not every vascular injury manifests during the early postoperative period and some may have a rapid deterioration course. There were a few patients in our cohort, who despite having a palpable pulse in the immediate postoperative period, exhibited vascular insufficiency at a later period. One patient presented on postoperative day 12 with an acute ischemia and a necrotic limb. The latter case highlights the importance of keeping a high index of suspicion for this complication. Any patient with extensive limb swelling, ongoing pain, and an incalcitrant postoperative course should be examined in person. Although these symptoms and signs may relate more to development of a deep venous thrombosis than an arterial injury, diligent monitoring of these patients is critical to avoid adverse outcome. All vascular problems in this cohort were arterial in nature. Injuries to veins can and do occur after TJA [12]. Venous injuries, however, may be more benign in course and, if minor, may escape detection. It is plausible that some patients in our large cohort may have experienced venous injuries that were not identified. Most venous injuries occur during placement of acetabular screws. Although none was identified in this cohort, we believe that at least one of the THA patients had an associated vein injury. Angiography is an extremely useful tool for diagnosis and confirmation of vascular injury. However, angiography should, in our opinion, be performed in a dedicated vascular suite and by a
1119
vascular expert to facilitate prompt treatment. A large number of patients with acute arterial thrombosis in this cohort could be treated by direct thrombectomy and cryotherapy successfully. Again, we realize that many institutions may lack such facilities. It is nonetheless crucial that intervention and revascularization can be carried out as soon as circumstances allow as the success of treatment is highly time dependent. A warm ischemia time interval of less than 6 hours is generally the accepted period within which arterial continuity must be restored to avoid permanent soft tissue damage [27]. Despite all the mentioned findings, the main question of the study still remains unanswered. Despite evaluating every possible parameter, it is difficult to determine if anything could have been done to prevent the vascular complications in this cohort or in general. All 16 patients in this cohort had documented palpable pulse preoperatively. Appropriate pressure (b350 mm Hg) and duration (b90 minutes) of tourniquet were used in the TKA cohort. All instruments used to expose the acetabulum were blunt and positioned with caution. Placement of screw was not the cause of any of the vascular injuries during THA. Intervention, in the form of revascularization, was implemented within a very short period of recognition or confirmation of the vascular injury. The one “inconsistent” issue in these patients related to compartment releases. Some patients did receive compartment release, and some did not “need” fasciotomy. The course of action was determined based on clinical decision. One of the major problems related to measurement of compartment pressure is that “normal” pressures in the compartments after TJA is not known. All the literature on compartment pressures is based on acute trauma models and is not applicable to TJA patients. Furthermore, the tendency to err on the side of caution and perform compartment release, besides the inconvenience of subjecting the patient to multiple additional surgeries, could result in an adverse outcome in patients with artificial joint as was seen in one patient in this series who developed periprosthetic infection. The other challenge identified during this study, patients whose vascular problem was identified at a later time point, calls us to question whether this was a result of late diagnosis or manifestation of the disease. The evaluation of medical records of every patient with late presentation revealed that a palpable pulse was documented in the immediate postoperative recovery and every morning during the hospital stay. Hence, lack of attention to the
1120 The Journal of Arthroplasty Vol. 23 No. 8 December 2008 vascular status did not seem to be the cause of late diagnosis. It appears that arterial occlusion, though exceedingly rare, can occur any time after TJA. In retrospect, one may argue that more diligent attention to the patient with delayed presentation (12 days postsurgery) may have prevented the need for amputation. Unfortunately, the lack of attention to the problem by the patient and delay in seeking medical advice was a large contributing factor in this particular case. On the basis of the findings of this study, we now ensure that important complications including arterial thrombosis, in spite of its extremely rare incidence, are discussed with the patients before discharge from the hospital. Nearly one half of the patients in our cohort elected to launch a legal suit against the operating surgeon. It is apparent from this patient series that there is a high likelihood of legal suits associated with orthopedic vascular complications. Surgical mishaps, misdiagnoses, improper treatments, and failure to diagnose are the leading cause of malpractice claims [28]. We were unable to identify any evidence for error in surgical practice or delivery of appropriate intervention in these patients. Furthermore, all patients had been informed regarding the potential of vascular complications before surgery. We heed the advice of a recent study on 2288 patients and 103 orthopedic surgeons that suggests that physicians who establish a rapport with the patient and explain the injury and treatment plan more effectively experience fewer subsequent malpractice claims [29,30]. It appears that despite all efforts to prevent or minimize risk, vascular complications after joint arthroplasty will continue to occur. Although vascular complications after TJA are exceedingly rare, the consequences are severe enough to necessitate a conversation with the patient before the operation. Patient awareness regarding this problem may then play a role in defraying the high likelihood of legal suits associated with this complication.
5.
6.
7.
8.
9.
10.
11.
12.
13. 14.
15.
16.
17.
18.
19.
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