Limiting Factors for Indication of Hip and Knee Arthroplasty in Chile: The International Perception of Risk Initiative.

BACKGROUND: An aging population with a resultant higher incidence of osteoarthritis have increased the need for total hip (THA) and knee arthroplasty (TKA) worldwide. The purpose of this study was to explore what medical and social risk factors are considered relevant by Chilean orthopaedic surgeons in decisions regarding indications for THA or TKA. METHODS: An anonymous survey was sent to 165 hip and knee arthroplasty surgeons who were members of the Chilean Orthopedics and Traumatology Society. From a total of 165 surgeons, 128 (78%) completed the survey. The questionnaire included demographic data, place of work, and inquired about medical and socioeconomic factors that could affect surgical indications. RESULTS: Factors that limited indications for elective THA/TKA included body mass index (81%), elevated hemoglobin A1c (92%), lack of social support network (58%), and low socioeconomic status (40%). Most respondents made decisions based on personal experience or literature review rather than hospital or departmental pressures. Of the respondents, 64% believe that some patient populations would benefit from better care if payment systems adjusted for their socioeconomic risk factors. CONCLUSION: In Chile, limitations regarding the indication for THA/TKA are most influenced by the presence of modifiable medical risk factors such as obesity, uncompensated diabetes, or malnutrition. We believe that the reason surgeons limit surgeries for such individuals is to promote better clinical outcomes, and not in response to pressure from paying entities. However, low socioeconomic status was perceived to impair the ability to achieve good clinical outcomes by 40% of the surgeons.

Femoral shaft fracture osteosynthesis in a critically ill patient under Extracorporeal Membrane Oxygenation (ECMO).

INTRODUCTION: Extracorporeal Membrane Oxygenation (ECMO) is an invasive procedure used in critically ill patients with catastrophic pulmonary failure or cardiogenic shock in which conventional management has failed. These patients are managed with permanent anticoagulation, with increased bleeding risk. Hemorrhage is the main reported complication. CASE: A 25-year-old polytraumatized woman, both lower limbs amputated and a left femoral shaft fracture with catastrophic pulmonary failure (Murray score 4) that required intensive management care with ECMO. During her evolution definitive femoral shaft osteosynthesis with a nail as required and the medical team decided to operate on the patient under ECMO. She recovered with fluctuations in her hematocrit, but was hemodynamically stable. The patient recovered satisfactorily, was weaned from ECMO and commenced her rehabilitation program. At 16 months, she was almost autovalent, and full consolidation was achieved, with no complication of the implants. DISCUSSION: ECMO is a life-saving support, but requires permanent anticoagulation, which implies a high risk of hemorrhages, specially for surgical treatment. This patient underwent an osteosynthesis surgery satisfactorily. Hematoma was the only complication of her intramedullary femoral nail, without compromising hemodynamics. This case shows that patients on ECMO can undergo a major orthopedic surgery in selected cases.

Cell therapy for cartilage defects of the hip.

BACKGROUND: Chondral injuries are commonly related to poor clinical outcome, but recent data showed some improvements in function and pain after hip arthroscopy. Cell-based therapies represent an appealing alternative strategy for cartilage regeneration, and interesting results have been recently reported after intra-articular injections of mesenchymal stem cells (MSCs). The results of hip arthroscopy for femoroacetabular impingement (FAI) and intra-articular injections of autologous expanded bone marrow - MSCs (BM-MSCs) are reported in this retrospective study. MATERIALS AND METHODS: Twenty patients (29 hips) received hip arthroscopy for FAI and focal cartilage injuries or mild to moderate osteoarthrosis (OA). Three intra-articular injections of 20×106 BM-MSCs were injected from 4 to 6 weeks postoperative. The modified Harris Hip score (mHHS), the WOMAC score, the VAIL score and VAS score were administered to all patients. RESULTS: The mean age of the patients was 51.8 years, and the mean follow-up was 24 months. The median preoperative mHHS, WOMAC and VAIL scores were 64.3, 73 and 56.5 respectively, and they increased to 91, 97 and 83 at final follow up (p<0.05). The VAS score also improved from a median of 6 to 2. Four patients received a THA (13% of the hips) at the median of 9 months post intervention (range 6-36 months). Six patients referred pain after the injection of MSCs, which improved with oral pain killers. No major complications were reported. CONCLUSION: BM-MSCc injections in combination with hip arthroscopy may improve the quality of life and functional score in patient with FAI and cartilage injuries which are still not candidate to a THA. LEVEL OF EVIDENCE: IV case series.

Arthroscopic release of iliopsoas tendon in patients with femoro-acetabular impingement: clinical results at mid-term follow-up.

BACKGROUND: The iliopsoas tendon is a recognized cause of extra-articular hip pain, and tenotomy has been described as an effective treatment in patients who do not respond to conservative treatments. Endoscopic release showed higher success rate, lower recurrence, fewer complications compared to open surgery. The aim of the study is to report the results at a mean of 4 years follow-up of a series of patients affected by femoroacetabular impingement (FAI) and an associated iliopsoas tendinopathy, treated with hip arthroscopy and transcapsular tendon release. METHODS: Fifteen patients were retrospectively reviewed. Assessment of radiographic signs of FAI was performed, the alpha angle, the femoral head-neck offset and the lateral center edge angle (LCEA) were collected. Osteoarthritis was assessed from the AP pelvic and graded according to the Tönnis classification. Modified Harris Hip Score (mHHS), VAIL score and VAS score were administered to all patients before surgery, at follow-up at 1 year (T1) and final follow-up (T2). RESULTS: We found a statistical significant improvement in functional scores (mHHS and VAIL score) from the baseline to T2. According to VAS score, a statistical significant improvement was also found from T0 to T2, from a median of 5.5 (range 3-7) to 0 (range 0-5) (P<0.001). Two patients referred a recurrence of pain one year after surgery who were treated conservatively. No other complications have been reported. CONCLUSION: Iliopsoas tendinopathy can be associated to FAI in some patients, and failure in diagnosing and treating may be the reason of poor results and a revision surgery. Arthroscopic iliopsoas tendon release seems to produce good clinical outcome, reducing pain and the rate of a revision surgeries. Level of evidence: IV case series.

Validity of the alpha angle measurement on plain radiographs in the evaluation of cam-type femoroacetabular impingement.

BACKGROUND: Cam-type femoroacetabular impingement is secondary to lack of concavity at the anterosuperior femoral head-neck junction, resulting in reduced femoral head-neck offset and femoral head asphericity. This morphologic deformity can be detected by MRI and plain radiographs and quantified using the alpha angle. QUESTIONS/PURPOSES: We evaluated the accuracy and reproducibility of plain radiography in the diagnosis of cam-type deformity. METHODS: Sixty-eight patients (37 females, 31 males) with a mean age of 38 years (range, 17-60 years) were treated for intraarticular hip pathology with 43 hips having cam-type femoroacetabular impingement and 25 having isolated labral tears. All patients had alpha angle measurements made on plain radiographs (AP pelvis, crosstable lateral, Dunn view) and multiplanar MRI using an alpha angle of more than 50.5° as the gold standard. RESULTS: The Dunn view had a sensitivity of 91%, specificity of 88%, positive predictive value of 93%, negative predictive value of 84%, and accuracy of 90% for diagnosing the cam deformity associated with femoroacetabular impingement. The Pearson correlation coefficients between the MRI and plain radiography values were 0.702, 0.552, and 0.349 for the Dunn, crosstable lateral, and AP views, respectively. CONCLUSIONS: Our observations validate the clinical use of the Dunn view in the evaluation of the femoral head-neck contour in cam-type femoroacetabular impingement. LEVEL OF EVIDENCE: Level I, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Analysis of retrieved acetabular components of three polyethylene types.

The polyethylene used in total hip arthroplasty has gone through many changes over the past several decades, including consolidation processes, resin types, method of sterilization, packaging, and the extent of crosslinking. To isolate the in vivo performance of material changes from implant system design changes, we assessed the postretrieval surface wear and damage of components made from three different polyethylene types used in a single implant system. The polyethylene types investigated are representative of the sequentially available bearing materials that have dominated use in total hip arthroplasty over the last several decades. Forty-six components with implantation durations of 12 to 96 months were assessed for surface wear and damage and for socket wear and creep volume change. Acetabular components made from highly crosslinked polyethylene had a 50% lower total damage score than components made from polyethylene that was either gamma-sterilized in air or in nitrogen. The wear and creep socket volume change was 80% and 90% lower for the highly crosslinked components compared with the gamma-sterilized in air and nitrogen groups, respectively. These data of direct component measurement are consistent with earlier predictions that recent changes in polyethylene material processing can lead to clinically improved bearing performance.