Assessing Leg Length and Offset in Anterior Total Hip Arthroplasty: Overlay Versus AP Pelvis Intraoperative Radiographic Techniques: A Retrospective Cohort Study.

INTRODUCTION: Two intraoperative radiographic techniques to determine leg length and offset during anterior total hip arthroplasty (THA) are the AP pelvis and overlay techniques. The AP pelvis method measures LLDs and offset using AP fluoroscopic images, whereas the overlay method uses printed images of the native and replaced hips. The purpose of this study was to compare these techniques regarding clinical and radiographic LLD and offset discrepancies. METHODS: Patients of a single surgeon at two hospitals from September 2017 to January 2021 were retrospectively reviewed. Clinically detectable LLD was recorded. Radiographic measurements were obtained from preoperative and postoperative radiographs. LLD was determined based on the vertical distance between the lesser trochanters and the ischial tuberosities. Total offset was measured using a combination of femoral and medial offset. The Student t-test, Fisher exact test, and Wilcoxon rank sum tests were used for statistical analysis. RESULTS: Seventy-one procedures were done using the overlay technique and 61 used for the AP pelvis technique. No significant differences were observed in mean postoperative LLD (2.66 versus 2.88 mm, P = 0.66) and mean postoperative offset discrepancy (5.37 versus 4.21 mm, P = 0.143) between the overlay versus AP pelvis groups. The mean preoperative to postoperative absolute difference in offset was less than 5 mm in both groups. Clinically detectable LLD was noted in six of 71 patients in the overlay group and one of 61 in the AP pelvis group (P = 0.123). CONCLUSION: No notable differences were observed in intraoperative leg length and offset discrepancies during direct anterior THA between the AP pelvis and overlay techniques, suggesting they are equally effective in determining LLD and offset intraoperatively. The choice of technique to use anterior THA should be based primarily on the surgeon's preference, comfort, and available resources.

Defining the Learning Curve of Anterior Total Hip Arthroplasty After Fellowship-specific Training.

PURPOSE: To investigate the learning curve associated with performing direct anterior total hip arthroplasty (THA) immediately after fellowship training in this approach. METHODS: This was a multicenter, retrospective study that collected data on all direct anterior THAs performed by four fellowship-trained arthroplasty surgeons in their first year of practice. Demographic data, surgical time, blood loss, surgical complications, and medical complications were recorded. Regression models were created to evaluate the outcomes of interest. A generalized linear mixed model was used to estimate the effect of the number of THA procedures performed, a proxy for surgical experience with this procedure, on the variables of interest. RESULTS: A total of 286 patients undergoing direct anterior THA were included in this study. A decrease in surgical complications after approximately 40 cases and a decrease in medical complications at 25 to 50 cases were observed. Both surgical time and blood loss showed no learning curve. CONCLUSION: Extensive training with a direct anterior approach during fellowship minimizes the learning curve for blood loss and surgical time, but it continues to exist regarding perioperative surgical and medical complications. Recent fellowship graduates should be cautious and expect a learning curve of around 40 cases before complication rates begin to normalize.

Does contralateral knee range of motion predict postoperative knee range of motion after total knee arthroplasty?

PURPOSE: The aim of this study was to determine if contralateral knee range of motion is associated with postoperative range of motion in the operative knee after total knee arthroplasty. METHODS: Contralateral (nonoperative) knee range of motion was compared to postoperative knee range of motion after total knee arthroplasty using linear regression models in 59 patients who had undergone primary total knee arthroplasty with a minimum of 4 months postoperative follow-up data (range 4-13 months). RESULTS: A strong linear relationship was observed between contralateral knee ranges of motion of 115° or greater and postoperative knee ranges of motion after total knee arthroplasty (slope 0.93, 95% CI 0.58-1.29, P < 0.0001), with a mean difference of -7.44° (95% CI -10.3 to -4.63, P < 0.0001). However, there was no association between contralateral knee range of motion and postoperative knee range of motion when contralateral knee range of motion was less than 115°. CONCLUSION: Contralateral knee range of motion of 115° or greater correlates linearly with postoperative range of motion after total knee arthroplasty, and thus may be predictive in such cases.

Multi-focal Lytic Lesions in a Patient with Myelofibrosis: A Case Report.

Myelofibrosis is a rare disorder that is classified as one of the myeloproliferative disorders. This particular disorder results in the abnormal proliferation of hematopoietic stem cells in the bone marrow. In some cases, such as ours, pathologic fractures can occur due to skeletal manifestations. We report on a rare finding of rapidly progressive lytic lesions in multiple regions throughout the body. This presentation of myelofibrosis behaving in a metastatic-like fashion has not been previously described.

Initial Experience With a Bioresorbable Polymer Anchor.

Background Anchors are frequently used in reconstructive orthopedic surgery to achieve fixation of soft tissue to bone. Anchors vary with respect to material composition, configuration, and methods of fixation at the site of attachment. The fixation component of anchoring devices has generally evolved from metal-fabricated implants to various types of bioresorbable anchors. The SonicAnchorTM (Stryker, Kalamazoo, MI USA) polymer implant provides a unique form of anchor fixation using SonicFusionTM technology to achieve interdigitation within cancellous bone while being radiolucent and providing a small footprint. Methods During a four-year period, 116 patients underwent a reconstructive orthopedic foot and ankle surgical procedure with the use of at least one bioresorbable polymer anchor (SonicAnchor implant). There were 59 males and 57 females, with an average age of 42 years (range: 12-83 years). Results A total of 233 bioresorbable anchor (SonicAnchor) implants were used in 116 patients. Of the 116 patients, 108 (93.1%) achieved successful clinical healing of their surgery at their most recent follow-up. The average follow-up duration was 309 days (range: 14-1,429 days). Eight (6.9%) patients were lost to follow-up prior to clinical healing. Two (1.7%) patients underwent reoperation. Also, 65 (56%) patients had at least six months of follow-up and 36 (31%) had at least one year of follow-up. Conclusions This preliminary clinical trial of patients undergoing soft tissue repair or reconstruction with a bioresorbable polymer appears to perform comparably to other commercially available devices. The lack of adverse events, mechanical failures, or infections further supports the safety of this device.