Faculty Bibliography

Insufficiency fractures present a significant problem in patients with osteoporosis. We report a case of bilateral iliac wing insufficiency fracture following low energy injury in an 87-year-old osteoporotic woman occurring 2 weeks after primary total hip arthroplasty. There are only a few reports of insufficiency fractures involving the ilium in the literature, and diagnosis has proven challenging, as radiographs are often negative at symptom onset. Magnetic resonance or radionuclide imaging is generally necessary for definitive diagnosis. This case highlights the importance of careful perioperative management of patients with osteoporosis.

We report the case of a woman in the third trimester of pregnancy who sustained an ankle fracture dislocation that could not be adequately closed reduced. After discussions with the patient, her obstetrician, and the anesthesiologists, she was indicated for surgical fixation. A heart tone monitor was used to assess fetal health during the procedure. During surgical incision, the fetus went into distress, and an emergency caesarian section was performed. After delivery of the infant and abdominal closer, surgery was completed. Due to a cohesive team effort, both the patient and her infant had excellent outcomes. There are many important considerations in the surgical management of the pregnant patient with traumatic orthopaedic injuries. Of especial importance to the orthopaedic surgeon is the impact of patient positioning on uteroplacental blood flow. This report discusses factors that should be taken into account by any orthopaedist who plans to operate on a pregnant patient.

Rising implant prices and evolving technologies are important factors contributing to the increased cost of arthroplasty. Assessing how patients value arthroplasty, new technologies, and their perceived outcomes is critical in planning cost-effective care, as well as evaluating new-technologies. One hundred one patients undergoing arthroplasty took part in the survey. We captured demographics, spending practices, knowledge of implants, patient willingness to pay for implants, and preferences related to implant attributes. When patients were asked if they would be satisfied with "standard of care" prosthesis, 80% replied "no". When asked if they would pay for a higher than "standard of care" prosthesis, 86% replied "yes". The study demonstrated that patients, regardless of their socio-economic status, are not satisfied with standard of care implants when newer technologies are available, and they may be willing to share in the cost of their prosthesis. Patients also prefer the option to choose what they perceive to be a higher quality or innovative implant even if the "out of pocket" cost is higher.

Knee malalignment during total knee arthroplasty (TKA) is commonly classified as either varus or valgus on the basis of a standing anteroposterior radiograph. Computer-assisted surgery (CAS) navigation TKA provides precise dynamic evaluation of knee alignment throughout the full range of motion (FROM). The goal of this study was to classify patterns of CAS-generated knee deformity curves that match specific soft tissue contracture combinations. This can then be applied as an algorithm for soft tissue balancing on the basis of the preoperative knee deformity curve. Computer navigation-generated graphs from 65 consecutive TKA procedures performed by a single surgeon were analyzed. A stress-strain curve of the coronal alignment of the knee was recorded throughout FROM before bony resection. All graphs were classified into groups according to their pattern. Cadaveric knee models were then used to test the correlation between isolated and combined ligamentous contractures and identified CAS deformity curves. An analysis of the intraoperative knee alignment graphs revealed four distinct patterns of coronal deformity on the basis of intraoperative data: 13% diagonal, 18.5% C-shaped, 43.5% comma shaped, and 25% S-shaped. Each represents the change in varus and valgus alignment during FROM. All patterns were reproduced with cadaveric knees by recreating specific contracture constellations. A tight posterior capsule gave an S-shaped curve, a tight lateral collateral ligament gave a C-shaped curve, tight medial collateral ligament gave a diagonal curve, and a tight posterior lateral corner gave a comma-shaped curve. Release of the specific contractures resulted in correction of all patterns of deformity as measured by CAS. We propose a new classification system for coronal plane knee deformity throughout FROM. This system intends to match individual and combined soft tissue pathological contractures to specific stress-strain curves obtained through routine knee CAS preparation. This classification system may provide surgeons with a general guide for soft tissue balancing during computer-navigated TKA.

Recent resurgence in the interest of barbed suture has extended its application to wound closures in total joint surgery. Improved suture biomaterials and barb geometry has lead to consideration for its use in various orthopedic procedures including arthroplasty. The reported superior wound tensile stress distribution, no need for knots, and ability to close multiple layers with one suture make it an attractive option for deep wound closure after total joint surgery. However, inherent to the design of this suture are barbs that pose a risk of glove perforation and the potential for the transmission of blood borne pathogens. This study reports no increase in the incidence of glove perforation with use of barbed suture for deep wound closure after total joint arthroplasty.

Recent advances in the medical management of patients with human immunodeficiency virus (HIV) have led to improvement in their life expectancy. The growing numbers of HIV-positive patients are now living long enough to develop end-stage arthritis, as well as other long-term musculoskeletal complications of HIV infection and treatment. This has resulted in an increased demand for total joint arthroplasty among these individuals. However, the safety and outcomes of such procedures are frequently questioned in published reports. Although increased complication rates have often been reported, most studies have reported on joint arthroplasties in HIV patients with hemophilia. The most widely reported complications in both HIV-negative and positive hemophiliac patients are aseptic loosening and postoperative infection. A possible relationship between the rate of these complications and cluster of differentiation (CD4) lymphocyte count has also been proposed. In addition to hemophilia, other factors frequently comorbid with HIV infection, such as intravenous drug use, can further complicate the clinical outcomes of these individuals following total joint replacement procedures. Physicians treating HIV positive patients must remain aware of the risks and outcomes of total joint surgery in this group when counseling them on treatment options.

Total hip arthroplasty has become the standard treatment for end stage osteoarthritis. It is one of the most successful surgeries in the orthopedic armamentarium. It has been demonstrated as an effective way to decrease pain, improve quality of life and restore function in old and young patients alike. However, postoperative complications are still a risk associated with joint arthroplasty, which most significantly impacts patients' results and the total cost of care. As the number of patients that undergo total hip arthroplasty increases, it is our goal to try and minimize the incidence of perioperative complications. Perioperative complication after total hip arthroplasty includes both surgical complications such as: neurovascular injury, limb-length discrepancy, instability, and periprosthetic fracture, as well as medical complication such as: postoperative infection, deep vein thrombosis, pulmonary embolism, postoperative anemia, and cardiopulmonary complications. It is the objective of this review to discuss the different perioperative complications that occur after total hip arthroplasty, and to layout the treatment and preventive measures that can be taken in order to limit their occurrence and decrease the associated morbidity.

BACKGROUND: The recognition of the importance of femoral acetabular impingement (FAI) as a potential cause of hip pain has been stimulated by major efforts to salvage hip joints by reconstruction in order to prevent or delay the need for replacement. The purpose of this review is to define the nature of FAI, the various types, and how to make the diagnosis. METHODS: The review describes the characteristics of the hip that cause FAI and emphasizes understanding that the femoral and acetabular components normally function as a unit, complementing each other. RESULTSCONCLUSION: The methods of making the diagnosis of FAI and their limitations are described. If the acetabulum and femur are considered to be independent of each other, conflict may occur, hindering function, and not be apparent. The increasing frequency of making this diagnosis based on abnormal anatomy on one side of the joint, often in face of unclear physical findings, can bring the diagnosis into question. FAI seen in Perthes disease and acetabular dysplasia is explained. Knowing how to analyze the hip, being aware of the limitations of various available clinical and diagnostic studies, and recognizing the continued and ever-changing extensive body of literature is important and challenging. This primer is just the beginning.

Bilateral hip arthroplasty has been reported to be a safe and effective way to treat bilateral hip arthritis in a selective group of patients. We report a follow-up of 30 patients who underwent simultaneous bilateral total hip arthroplasty with hydroxyapatite implants and were followed for an average of 19.4 years. Patients had an average Harris Hip Score of 90 at the latest follow-up (range, 78-99). The average Western Ontario and McMaster Universities Arthritis Index questionnaire index score was 12 (range, 0-41), with high functional results on the 12-Item Short Form Health Survey (SF-12) and Oxford 12 questioners. Using the Kaplan-Meier survivorship analysis, with revision for any reason as an end point, survivorship was 94% at 12 years, 88% at 15 years, 74% at 18 years, and 61% at 23 years. All revisions were for the acetabular component, and the survivorship for the femoral component was 100% throughout the 23-year period. We conclude that bilateral uncemented total hip arthroplasty can provide satisfactory long-term clinical, radiological, and functional outcomes in patients even with older-generation polyethylene liners and stem designs.

PURPOSE: Rotating hinge knee prostheses are known to provide inherent stability. Yoke fractures of the hinged tibial insert of modern generation rotating hinge devices are a matter of continued concern. The aim of this study was to describe incidence and management of yoke fracture of the LPS hinged tibial insert. METHODS: Retrospective data analysis of two institutions identified 40 patients with a LPS total knee arthroplasty. Implant survival and prosthetic complications was calculated according to Kaplan-Meier. RESULTS: Out of the group of 40 patients, four fractures of the metal yoke occurred in four cases (failure rate: 10%). Furthermore, a second fracture occurred in two patients. The overall revision-free prosthetic survival was 57% at 38 months, while prosthetic survival until yoke fracture was 86% at 38 months. CONCLUSION: Handling yoke fractures as mechanical complication includes replacing the hinged insert, stabilization of the joint and joint line height preservation in order to decrease the cantilever effect at the insert-base plate interface.