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Which of the following is the most common intraoperative complication in a patient with sickle cell disease undergoing a total hip arthroplasty?
Periprosthetic fracture distal to the implant
Iatrogenic fracture causing pelvic discontinuity
Perforation of the femoral canal
Cardiac arrest from fat embolization to lungs
Injury to the sciatic nerve
Select Answer to see Preferred Response
Perforation of the femoral canal during preparation of the femur is not an uncommon complication, with rates ranging from 4.9-18.2%.
While total hip arthroplasty is extremely effective for pain relief in patients with osteonecrosis of the hip secondary to sickle cell disease, the procedure carries a higher rate of complications compared with non-sickle cell disease patients. Particular attention should be given to the preparation of the femur as femoral medullary widening from chronic marrow hyperplasia adjacent to patchy areas of dense sclerosis can make preparation of the canal difficult. Some surgeons prefer to ream over a guide-wire to avoid perforation.
Jeong et al. reviewed total hip arthroplasty in patients with sickle cell disease. Amongst other things, they discuss the difficulties associated with preparation of the femoral canal, quoting a perforation rate between 4.9-18.2%. They also state there are no prospective studies comparing cementless to cemented THA, but retrospective data has shown promising results with cementless components.
Hernigou et al. retrospectively reviewed 244 patients with sickle cell disease that underwent cemented total hip arthroplasty. They had a 3% infection rate, a relatively low rate of revision for aseptic loosening, and a 27% rate of medical complications. Overall, they viewed their results as favorable.
Illustration A shows a patient with bilateral AVN secondary to sickle cell disease. Note the areas of patchy dense sclerosis in the metaphyseal region of the proximal femur.
Answer 1: Periprosthetic fracture usually occurs at the area of perforation, not distal to the implant.
Answer 2: Acetabular fractures are more common in this patient population as well, but the rate of iatrogenic pelvic discontinuity is lower than that of femoral perforation.
Answer 4: The rate of cardiac arrest from fat embolization to the lungs is quite low.
Answer 5: While injury to the sciatic nerve is possibly, it has not been shown to be more common in this patient population. The rate of post-operative hematoma causing sciatic nerve dysfunction may be higher in this patient population.
Jeong GK, Ruchelsman DE, Jazrawi LM, Jaffe WL.
J Am Acad Orthop Surg. 2005 May-Jun;13(3):208-17. PMID: 15938609 (Link to Abstract)
Hernigou P, Zilber S, Filippini P, Mathieu G, Poignard A, Galacteros F.
Clin Orthop Relat Res. 2008 Feb;466(2):300-8. Epub 2008 Jan 10. PMID: 18196410 (Link to Abstract)
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Average 3.0 of 18 Ratings
A 45-year-old with a history of sickle cell anemia reports hip pain for the past 6 months. A radiograph of the affected hip is shown in Figure A. Which of the following interventions has been shown to have the best outcomes in this patient population?
Uncemented metal on polyethylene total hip arthroplasty
Cemented metal on polyethylene total hip arthroplasty
Based on the radiographs and current literature, the best intervention is an uncemented metal on polyethylene total hip arthroplasty.
Avascular necrosis of the hip may be idiopathic in nature or associated with alcoholism, steroid use, or as in this case, sickle cell anemia. The Ficat staging system is used to classify avascular necrosis of the hip. Changes in treatment are driven by development of symptoms as well as the development of subchondral bone collapse (Ficat Stage 3). In those with with femoral head flattening (Ficat Stage 4) and acetabular degenerative changes (Ficat Stage 5), total hip replacement has good to excellent outcomes.
Mont et al. review surgical options for avascular necrosis of the hip. Head preserving procedures are generally reserved for those patients where the femoral head has not collapsed. Collapse and associated arthritis warrant utilization of arthroplasty procedures.
Mont et al. conducted a systematic review to better delineate the symptomatic progression of asymptomatic avascular necrosis of the hip. They found that patients with sickle cell disease have the highest rate of progression to collapse. Medium sized, laterally located lesions were associated with a higher frequency of collapse and joint preserving procedures are recommended for these.
Figure A shows radiograph of a patient with avascular necrosis; note the femoral head flattening, narrowing of the joint space and acetabular sclerosis.
Answer 1: Conservative measures in this patient would not improve this patient’s outcome give the degree of the femoral head collapse and presence of acetabular degeneration.
Answer 2: Bisphosphonates can be used in patients with avascular necrosis of the hip prior to collapse. Current data is conflicting as to whether they prevent collapse or not.
Answer 3: Outcomes for patients undergoing hemiarthroplasty for avascular necrosis of the hip in the young patient are poor; and as a result, this has been largely abandoned.
Answer 5: Higher failure rates have been seen in patients undergoing cemented total hip arthroplasty in treatment of avascular necrosis of the hip.
Mont MA, Ragland PS, Parvizi J.
Instr Course Lect. 2006;55:167-72. PMID: 16958449 (Link to Abstract)
Mont MA, Zywiel MG, Marker DR, McGrath MS, Delanois RE
J Bone Joint Surg Am. 2010 Sep;92(12):2165-70. PMID: 20844158 (Link to Abstract)
Average 3.0 of 12 Ratings
A 65-year-old patient was treated with an open reduction/internal fixation for a left femoral neck fracture sustained 25 years ago. Five years ago he developed hip pain and was converted to a left hip hemiarthroplasty. He presents with complaints of groin pain for the past 6 weeks. A recent radiograph is shown in Figure A. The patient’s physical exam is limited secondary to pain. Serum laboratory values are WBC-8.0, ESR-20, CRP-0.5. A synovial fluid aspirate of the hip demonstrates < 500 cells (60% PMN). What is the most likely cause of this patient's symptoms?
Infected hip hemiarthroplasty
Impingement of the hip hemiarthroplasty
Based on the history, radiographs, and laboratory values, the patient has developed failure of his hip hemiarthroplasty. At this point in time he warrants a conversion to a total hip arthroplasty.
Avascular necrosis (AVN) of the femoral head after traumatic injury to the femoral neck occurs at an incidence of 10-45%. Although the risk increases with failure to anatomically reduce the fractue, it can still occur in non displaced settings. Treatment of avascular necrosis in older patients includes hip hemiarthroplasty or a total hip replacement. With the former, development of acetabular protrusio can contribute to groin symptoms. Functional outcomes have been reported to be higher in those receiving total hip replacement for AVN of the femoral head.
Lee et al. prospectively compared the use of bipolar hip hemiarthroplasty versus total hip arthroplasty for advanced stages of AVN of the femoral head (Ficat Stage 3). Total hip scores were most improved in the total hip arthroplasty group. Migration of the outer head in the hemiarthroplasty group was seen in 23% of patients. They recommend use of a total hip arthroplasty in patients with Ficat Stage 3 AVN of the femoral head
Ito et al. evaluated the outcomes of patients who underwent bipolar hemiarthroplasties for femoral head avascular necrosis. They found that proximal migration and acetabular degeneration were risk factors for groin symptoms. They also found that outcomes were inferior to patients who had undergone total hip arthroplasty for AVN of the femoral head. They recommend use of total hip arthroplasty in advanced osteonecrosis of the femoral head
Diwanji et al. evaluated outcomes of patients who underwent a conversion from a bipolar hip arthroplasty to total hip arthroplasty in 25 patients. Thirteen (52%) patients were revised to THA because of acetabular erosions. Follow up was completed for an average of 7.2 years. At final follow-up, they found improvement of the Harris Hip Scores and improvement of the pain portion of the WOMAC index. They recommend use of total hip replacement as an option to salvage failed bipolar hip hemiarthroplasty
Figure A shows the radiograph of a hip hemiarthroplasty where acetabular protrusion has developed.
Answer 2: There is no evidence of infection based on laboratory results.
Answer 3: There is no evidence of lumbar based pathology in this patient.
Answer 4: While impingement could be a cause of pain, it is not as likely given the history, clinical findings and radiographs seen here.
Answer 5: While irritation of the iliopsoas could occur, it is not as likely given the radiograph seen here.
Lee SB, Sugano N, Nakata K, Matsui M, Ohzono K.
Clin Orthop Relat Res. 2004 Jul;(424):161-5. PMID: 15241159 (Link to Abstract)
Ito H, Matsuno T, Kaneda K.
Clin Orthop Relat Res. 2000 May;(374):201-11. PMID: 10818981 (Link to Abstract)
Diwanji SR, Kim SK, Seon JK, Park SJ, Yoon TR.
J Arthroplasty. 2008 Oct;23(7):1009-15. Epub 2008 Mar 4. PMID: 18534504 (Link to Abstract)
Average 3.0 of 7 Ratings
A 47-year-old man presents with 1 week of left leg pain. 6 months prior he underwent a vascularized free-fibula bone graft from his left leg to his right hip for avascular necrosis. The pain is located at the level of his donor site and is worse with weight-bearing and relieved by rest. Physical exam shows focal tenderness over his tibia. A lateral radiograph from the day of presentation is shown in Figure A. WBC, ESR, and CRP are all within normal limits. What is the next best step in management to confirm the diagnosis?
Compartment pressure measurements
Ultrasound to rule out deep abscess
The clinical presentation is suspicious for a stress fracture of the tibia following free-fibula bone grafting. If plain radiographs are negative, more sensitive imaging such as a MRI or bone scan should be performed.
Tibial stress fractures are a known complication following free-fibula bone grafting. Radiographs may be normal (as is the case in figure A), or might show the "dreaded black line" and/or new periosteal bone formation. If a stress fracture is confirmed with imaging, appropriate management would then consist of protective weight bearing until symptoms subside.
Pacifico et al detail a case report of tibial stress fractures after vascularised free-fibula graft to the mandible. They report non-traumatic stress fracture to the tibia following a vascularised free-fibula graft is an uncommon but important complication.
Ivey et al detail a case report of a tibial stress fracture after vascularised free-fibula graft for repair of non-union of the humerus.
Emery et al report a case-series of 5 patients who sustained tibial stress fractures after a graft had been obtained from the ipsilateral fibula for use in anterior reconstruction of the spine. They theorize that the increased load the tibia bears as a result of the missing fibular graft may result in stress fractures.
Illustration A shows new periosteal bone formation on the lateral cortex of the tibia consistent with a stress fracture.
Incorrect Answer Choices:
1: While compartment syndrome is on the differential diagnosis, his signs and symptoms are not most consistent with that diagnosis.
2: While CT scan may show evidence of a stress fracture, MRI/bone scans have been shown to be superior methods for detection.
4: As infectious laboratories are normal, an ultrasound to rule out a deep abscess would likely be negative.
5: Bone biopsy is not appropriate without evidence of a lesion or concern for osteomyelitis.
Pacifico MD, Floyd D, Wood SH.
Br J Plast Surg. 2003 Dec;56(8):832-4. PMID: 14615264 (Link to Abstract)
Ivey M, Hicks CA, Hook JD.
Orthopedics. 1995 Jan;18(1):57-60. PMID: 7899169 (Link to Abstract)
Emery SE, Heller JG, Petersilge CA, Bolesta MJ, Whitesides TE Jr.
J Bone Joint Surg Am. 1996 Aug;78(8):1248-51. PMID: 8753718 (Link to Abstract)
Average 3.0 of 21 Ratings
In patients with sickle cell disease and asymptomatic osteonecrosis of the femoral head identified with magnetic resonance imaging, what percentage will eventually go on to femoral head collapse?
11% to 25%
26 to 50%
51 to 75%
Untreated asymptomatic osteonecrosis of the femoral head in patients with sickle cell disease has a > 75% likelihood of progression to pain and collapse.
In contrast to asymptomatic osteonecrosis in patients without sickle cell disease, patients with sickle cell disease have a high incidence of progression to collapse and functional impairment secondary to pain (33% compared to 75%, respectively). In patients with sickle cell disease who present with a symptomatic hip, the contralateral (presumably asymptomatic) hip should be screened carefully and periodically for signs of disease. Given the high rate of progression, some argue for operative treatment of the asymptomatic hip at the same time the symptomatic hip is being treated.
Hernigou et al. studied patients with sickle cell disease who had symptomatic avascular necrosis (AVN) in one hip and asymptomatic AVN in the contralateral hip. Their goal was to understand the natural history of the asymptomatic side. Ninety-one percent eventually developed pain and 77% developed collapse. Collapse was preceded by symptoms of pain in all patients.
Aguilar et al. report bone and joint disorders are the most common cause of chronic pain in patients who have sickle cell disease, and that the femoral head is the most common area of bone destruction in sickle cell patients.
Answers 1-4: Patients with sickle cell disease and osteonecrosis of the femoral head have a high rate of progression to painful collapse.
Hernigou P, Habibi A, Bachir D, Galacteros F.
J Bone Joint Surg Am. 2006 Dec;88(12):2565-72. PMID: 17142405 (Link to Abstract)
Aguilar C, Vichinsky E, Neumayr L.
Hematol Oncol Clin North Am. 2005 Oct;19(5):929-41, viii. PMID: 16214653 (Link to Abstract)
Average 2.0 of 78 Ratings
A 40-year-old man complains of increasing groin pain. Radiographs show femoral head avascular necrosis with subchondral lucency but without femoral head collapse. Which of the following medical treatments have been shown to decrease the risk of subsequent femoral head collapse?
Cyclic parathyroid hormone therapy
RANK ligand therapy
Selective estrogen receptor modulator therapy
Bisphosphonate therapy is a proven method of preventing femoral head collapse in patients with avascular necrosis and subchondral lucency.
Lai et al evaluated the effect of alendronate on patients with Steinberg stage-II or III osteonecrosis of the femoral head. They found that alendronate prevented early collapse of the femoral head at twenty-four months.
Agarwala et al evaluated the effect of bisphosphonate therapy on patient reported and radiographic outcomes in femoral head avascular necrosis. They found alendronate reduces pain, improves function and may prevent disease progression at 5 year followup.
Nishii et al evaluated the effect of alendronate on 20 hips with osteonecrosis of the femoral head without collapse. They found a lower frequency of collapse and less patient reported pain in patients treated with bisphosphonate therapy compared to controls at 12 month follow up.
Thanks to Dr. Chris Rice at UW Madison:
"Recent level 1 evidence seems to cast doubt on the efficacy of bisphosphonate treatment in precolapse AVN with medium to large lesions. There is also some thought that the supposed success seen in smaller lesions is due to the natural history of these lesions which often do not progress to collapse even in the absence of any treatment. "
Lee YK, Ha YC, Cho YJ, Suh KT, Kim SY, Won YY, Min BW, Yoon TR, Kim HJ, Koo KH Does Zoledronate Prevent Femoral Head Collapse from Osteonecrosis? A Prospective, Randomized, Open-Label, Multicenter Study. J Bone Joint Surg Am. 2015 Jul 15.
Answer 1: Cyclic parathyroid hormone therapy is used in osteoporosis treatment, and not in the treatment of femoral head avascular necrosis.
Answer 3 & 4: Neither RANK nor RANK ligand are being used in therapeutic forms currently. Denosumab, an anti-RANK ligand antibody, has shown early success in the treatment of bone lysis in oncologic applications.
Answer 5: Selective estrogen receptor modulator therapy is used in osteoporosis, and not in the treatment of femoral head avascular necrosis.
Lai KA, Shen WJ, Yang CY, Shao CJ, Hsu JT, Lin RM
J Bone Joint Surg Am. 2005 Oct;87(10):2155-9. PMID: 16203877 (Link to Abstract)
Agarwala S, Jain D, Joshi VR, Sule A.
Rheumatology (Oxford). 2005 Mar;44(3):352-9. Epub 2004 Nov 30. PMID: 15572396 (Link to Abstract)
Nishii T, Sugano N, Miki H, Hashimoto J, Yoshikawa H
Clin. Orthop. Relat. Res.. 2006 Feb;443:273-9. PMID: 16462451 (Link to Abstract)
Average 3.0 of 24 Ratings
A 41-year-old male has steroid-induced avascular necrosis of the hip and decides to undergo metal on polyethylene total hip arthroplasty. His 80-year-old, sedentary father had a total hip replacement 5 years ago. With comparison to his father, the patient should be informed of the following risk?
Increased risk of sciatic nerve palsy
Increased longevity of prothesis
Increased risk for polyethylene wear and osteolysis
Reduced range of motion
Lower likelihood of revision surgery
A younger, active patient will sustain more polyethylene wear and osteolysis due to greater activity levels and more years of use.
Kim et al prospectively studied 98 consecutive patients with osteonecrosis of the femoral head with an average follow-up was 9.3 years. Although there was no aseptic loosening of the components, they reported a high rate of linear wear of the polyethylene liner and a high rate of osteolysis in these high-risk young patients (16% in cemented femoral stems, 24% in uncemented stems).
Kim YH, Oh SH, Kim JS, Koo KH.
J Bone Joint Surg Am. 2003 Apr;85-A(4):675-81. PMID: 12672844 (Link to Abstract)
Average 3.0 of 25 Ratings
HPI - 58 yo female with progressive left hip pain and limp for 6 months. No history of trauma or other predisposing factors. No prior treatment.
What is the best treatment for this patient?
HPI - History of injury to right hip joint 15 yrs back.Fixed with Moore's pin
Went into avascular necrosis
How would you remove the screws during surgery?
HPI - 13 months ago insidious onset of left hip pain which progressively become worse. Sudden deterioration after a sickle cell crisis. Now left hip is Ficat stage III. He started feeling discomfort with his right hip about two months ago. Now right hip is Ficat stage IIA (Precollapse stage)
What is the best combination of bearing surfaces for left THA
HPI - Patient had hip trauma 35 yrs back .no record available
Will flexion deformity 20 degree will correct with physio or release needed
HPI - 6 month history of left hip pain with evidence of AVN but no collapse
How would you treat painful AVN without any collapse in a young patient with sickle cell disease