German A. Marulanda

Use of metal-on-metal total hip resurfacing for the treatment of osteonecrosis of the femoral head.

BACKGROUND Recently, with the advent of improved metal-on-metal prostheses, total hip resurfacing has emerged as a viable arthroplasty option. However, it remains controversial whether this procedure should be used in patients with osteonecrosis when the femoral resurfacing component is cemented onto dead bone. The purpose of this study was to analyze the clinical and radiographic outcomes of metal-on-metal total hip resurfacing arthroplasty in patients with osteonecrosis of the femoral head. In addition, this group was compared with a matched group of patients who were diagnosed as having osteoarthritis. METHODS Forty-two osteonecrotic hips that were treated with a metal-on-metal total hip resurfacing arthroplasty were studied. They were matched by gender, age, prosthesis, surgeon, and surgical approach to forty-two osteoarthritic hips that were treated with the same metal-on-metal prosthesis. In the osteonecrosis group, there were twenty-five men and eleven women, and in the osteoarthritis group, there were twenty-eight men and thirteen women. The mean age at the time of surgery was forty-two years. Patients were followed both clinically and radiographically for a mean of forty-one months. RESULTS The clinical outcomes were similar for both groups, with a good or excellent outcome in thirty-nine hips (93%) with osteonecrosis and a good or excellent outcome in forty-one hips (98%) with osteoarthritis. In each of the two groups, there were two failures that required conversion to a standard total hip arthroplasty. Survivorship curves were similar for the two patient groups. CONCLUSIONS The short-term results for metal-on-metal total hip resurfacing for this challenging patient population with osteonecrosis were excellent and comparable with those seen in patients with osteoarthritis. We await long-term results to see if these early results are maintained. LEVEL OF EVIDENCE Prognostic Level II. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Systematic Analysis Of Classification Systems For Osteonecrosis Of The Femoral Head

BACKGROUND Multiple classification systems for osteonecrosis of the hip have been developed to assist physicians in the diagnosis and treatment of this potentially debilitating disorder. The purpose of this analysis was to delineate the classification systems utilized in reports published since 1985 and, through a comparison of the most commonly used systems, to identify consistent factors that would allow for cross-publication comparisons to be made. METHODS We performed a PubMed search for reports of outcome studies concerning treatment methods for osteonecrosis of the hip. All studies of reported outcomes with greater than ten patients were included in the analysis. Various classification systems were tabulated to determine usage frequencies. The four most commonly used systems were then analyzed to determine common factors used for classification. RESULTS One hundred and fifty-seven studies were available for analysis. Sixteen major classification systems that made use of more than one radiographic factor were identified, and nine of these systems had one to five modifications reported throughout the literature. Additionally, eleven other systems made use of single factors obtained from either magnetic resonance imaging or anatomic data. The review revealed that four classification systems accounted for greater than 85.4% of the reported studies. Parameters for these four systems were stratified to allow for uniformity of patient or study evaluation. CONCLUSIONS This analysis of the reported classification systems for osteonecrosis of the femoral head revealed several similarities between the most commonly used systems. An analysis of patients can be made with any of the four major systems if specific data are collected according to various magnetic resonance imaging and radiographic findings. This approach will allow for easier comparison of studies across different centers. LEVEL OF EVIDENCE Prognostic Level III. See Instructions to Authors on jbjs.org for a complete description of levels of evidence.

Orthopedic surgery options for the treatment of primary osteosarcoma.

BACKGROUND Osteosarcoma is the most common malignant primary neoplasm of bone. Orthopedic procedures are essential components in the multidisciplinary treatment of osteosarcoma. Limb-salvaging procedures offer adequate disease control comparable to the results obtained by amputations. This review discusses the advantages and disadvantages of the various types of amputations and the limb-salvaging techniques for the treatment of osteosarcoma. METHODS The authors analyzed the characteristics of limb-salvaging procedures and amputations for osteosarcoma. Qualitative and quantitative studies published in the English language that are listed in the National Library of Medicine were used as the basis for this review. In addition, a review of an expandable prosthesis is included. RESULTS Limb-salvaging techniques have acceptable rates of disease control. However, amputation remains a valid procedure in selected cases of osteosarcoma in most parts of the world. Orthopedic oncology surgeons have various materials, procedures, and techniques available to achieve disease control and improve function in patients with osteosarcoma. CONCLUSIONS The surgical management of patients with osteosarcoma is challenging. No difference in survival has been shown between amputations and adequately performed limb-salvaging procedures. Optimal tumor resection and a functional residual limb with increased patient survival are the goals of modern orthopedic oncology.

Surgical treatment and customized rehabilitation for stiff knee arthroplasties.

Treating patients who have arthrofibrotic or stiff knees after total knee arthroplasty can be difficult. Treatment with arthroscopic débridement, arthrolysis of adhesions with polyethylene spacer exchange, or complete revision arthroplasty often has led to less than optimal range of motion and functional outcomes. We used a combination of surgical arthrolysis and an intensive postoperative rehabilitation protocol, including functional bracing, to treat this condition. We then retrospectively reviewed 18 knees in 17 patients who had stiff knees after total knee arthroplasty with no other detectable clinical or radiographic abnormalities, at a mean followup of 30 months. Seventeen knees (94%) had gains in knee range of motion with a mean increased range of motion of 31°. Although 16 of 17 patients had clinical improvement and were satisfied with the procedure, only ⅔ of the patients (12 of 18 patients) had excellent or good Knee Society objective scores. This combined surgical and rehabilitation method can lead to an increased range of motion. All patients improved clinically, but good functional results were less predictable. The authors think treatment of these difficult knees should be aimed at soft tissue operative releases supplemented by an intensive rehabilitation protocol.Level of Evidence: Therapeutic study, level IV (prospective study). See Guidelines for Authors for a complete description of levels of evidence.

Functional problems and arthrofibrosis following total knee arthroplasty.

Improved surgical techniques and multidisciplinary rehabilitation protocols that involve coordination among surgeons, physical therapists, anesthesiologists, and social services personnel have led to excellent knee function and range of motion in a large percentage of patients following total knee arthroplasty. Nevertheless, there remains a small number of patients with persistent dysfunction that is difficult to treat1-4. Functional problems following total knee arthroplasty may be incapacitating as a result of persistent pain5, instability6, and a limited range of motion7. It has been shown recently that there is a direct correlation between a decreased range of motion following surgery and a lower perceived quality of life as evaluated with use of the Short Form-36 health survey questionnaire8. Continued dysfunction for any reason ultimately leads to decreased patient satisfaction. There is controversy about treatment methods for patients for whom initial rehabilitation efforts are unsuccessful following total knee arthroplasty. The reported efficacy of both noninvasive and invasive treatment modalities has been variable, with the percentage of patients obtaining improvement ranging from 0% to 90%3,9-12. Patients who have continued dysfunction despite initial rehabilitation efforts may require revision surgery. However, patients who have well-aligned, well-fixed prosthetic components will likely not benefit from a complete revision. Treatment of arthrofibrosis, scarring, soft-tissue contractures, and/or other soft-tissue dysfunction should involve less invasive treatment protocols before surgical options are considered. Nonoperative treatment modalities for restoring the range of motion include intensive rehabilitation protocols, static or dynamic splinting, injections, and application of serial casts13. Manipulation with the patient under anesthesia and invasive procedures, including arthroscopic debridement, open debridement with or without polyethylene exchange, and complete component revision, have been utilized when initial nonoperative rehabilitation efforts have failed. As a result of the …

Percutaneous drilling for the treatment of secondary osteonecrosis of the knee

Osteonecrosis of the knee comprises two separate disorders, primary spontaneous osteonecrosis which is often a self-limiting condition and secondary osteonecrosis which is associated with risk factors and a poor prognosis. In a series of 61 knees (38 patients) we analysed secondary osteonecrosis of the knee treated by a new technique using multiple small percutaneous 3 mm drillings. Total knee replacement was avoided in 59 knees (97%) at a mean follow-up of 3 years (2 to 4). Of the 61 knees, 56 (92%) had a successful clinical outcome, defined as a Knee Society score greater than 80 points. The procedure was successful in all 24 knees with small lesions compared with 32 of 37 knees (86%) with large lesions. All the procedures were performed as day cases and there were no complications. This technique appears to have a low morbidity, relieves symptoms and delays more invasive surgery.

Reductions in blood loss with a bipolar sealer in total hip arthroplasty.

Altogether, 50 primary total hip arthroplasties were performed in a prospective, blinded, randomized study comparing a bipolar sealer device to standard electrocautery for hemostasis. Cohorts were evaluated for intra- and postoperative blood loss, transfusion rate, hemoglobin levels and modified Harris hip scores. Variables such as age, gender and body mass index were correlated to transfusion requirements. Total blood loss in the bipolar sealer group was decreased by 40% and transfusions were reduced by 73%. There was a significant reduction in the intra- and postoperative blood loss, p = 0.002 and p = 0.001, respectively. There was no difference in clinical hip scores between groups. The bipolar sealer was an effective coagulation alternative for total hip arthroplasties, reducing blood loss and transfusion requirements without affecting outcome. It appears to reduce tissue damage and smoke production in comparison with standard electrocautery. These results were found even in patients with demographic characteristics associated with a higher risk of blood-related complications.

Outcome of lower-limb preservation with an expandable endoprosthesis after bone tumor resection in children.

BACKGROUND The optimal treatment of malignant pediatric lower-extremity bone tumors is controversial. Expandable endoprostheses allow limb preservation, but the revision rate and limited function are considered barriers to their use. This study investigated the functional, emotional, and oncologic outcomes of thirty-eight patients treated with an expandable endoprosthesis. METHODS A retrospective chart review was performed, and surviving patients were asked to complete the Musculoskeletal Tumor Society (MSTS) outcomes instrument and the Pediatric Outcomes Data Collection Instrument (PODCI). Additional data including the range of hip and knee motion, limb-length discrepancy, and total lengthening were also obtained. RESULTS Thirty-eight patients were treated with an expandable endoprosthesis, and twenty-six of these patients were alive at the time of the study. The mean global MSTS score was 26.1, and the mean global PODCI score was 85.8. The mean emotional acceptance and happiness subscores were high. The mean sagittal-plane hip motion in patients who had undergone replacement of the proximal aspect of the femur was 103°. The mean knee motion in patients who had undergone replacement of the proximal aspect of the femur, the distal aspect of the femur, or the proximal aspect of the tibia was 127°, 97°, and 107°, respectively. The mean lengthening at the time of skeletal maturity was 4.5 cm, and the mean limb-length discrepancy was 0.7 cm. Forty-two percent of the patients experienced complications, with ten patients requiring prosthesis revision and two of these patients requiring amputation. CONCLUSIONS Current technology does not offer a single best reconstruction option for children. Previous studies and the present series have indicated that physical and emotional functioning in patients treated with an expandable endoprosthesis are good but that complication rates remain high. Amputation and rotationplasty are alternative treatments if patients and their families are amenable to these procedures. The literature supports no single superior treatment among these three options with regard to physical or emotional health.

Resurfacing for Perthes Disease : An Alternative to Standard Hip Arthroplasty

Metal-on-metal total hip resurfacing is an alternative to conventional total hip arthroplasty with several reports describing the benefits of this procedure in young patients. We retrospectively compared the clinical (including range-of-motion and leg length restoration) and radiographic outcome of resurfacing in young patients with Legg-Calvé-Perthes to those of patients of a similar age treated with a standard total hip arthroplasty. Eighteen patients (19 hip resurfacings) who had a mean age of 33 years (range, 18-34 years) were followed for a minimum of 26 months (mean, 51 months; range, 26-72 months). We used an anterolateral approach in four hips and a posterior approach with a trochanteric advancement in 15 hips. Eighteen of the 19 hips had Harris hip scores greater than 80 points at final followup. All patients improved range of motion while avoiding any clinically apparent impingement. Leg length was gained in 16 hips where preoperative measurements were available. The short-term results of hip resurfacing for the treatment of Perthes disease compare similarly to those found in the literature for standard total hip arthroplasty in young patients. The trochanteric advancement technique described may aid in treating the deformed femoral anatomy.Level of Evidence: Level IV, case series study. See the Guidelines for authors for a complete description of levels of evidence.

Hip abductor moment arm - a mathematical analysis for proximal femoral replacement

BackgroundPatients undergoing proximal femoral replacement for tumor resection often have compromised hip abductor muscles resulting in a Trendelenberg limp and hip instability. Commercially available proximal femoral prostheses offer several designs with varying sites of attachment for the abductor muscles, however, no analyses of these configurations have been performed to determine which design provides the longest moment arm for the hip abductor muscles during normal function.MethodsThis study analyzed hip abductor moment arm through hip adduction and abduction with a trigonometric mathematical model to evaluate the effects of alterations in anatomy and proximal femoral prosthesis design. Prosthesis dimensions were taken from technical schematics that were obtained from the prosthesis manufacturers. Manufacturers who contributed schematics for this investigation were Stryker Orthopaedics and Biomet.ResultsSuperior and lateral displacement of the greater trochanter increased the hip abductor mechanical advantage for single-leg stance and adduction and preserved moment arm in the setting of Trendelenberg gait. Hip joint medialization resulted in less variance of the abductor moment arm through coronal motion. The Stryker GMRS endoprosthesis provided the longest moment arm in single-leg stance.ConclusionsHip abductor moment arm varies substantially throughout the hips range of motion in the coronal plane. Selection of a proximal femur endoprosthesis with an abductor muscle insertion that is located superiorly and laterally will optimize hip abductor moment arm in single-leg stance compared to one located inferiorly or medially.