Introduction: Malposition of the pelvis at the time of acetabular component insertion can contribute to malpositioning of the acetabular component. This study measures the variation in intraoperative positioning of the pelvis on the operating table during surgery by matching intraoperative radiographs with pre-operative computed tomograms (CT) using 2D-3D matching.

Methods: This prospective study was comprised of a random sample of 45 patients (n = 45, 26 female, 19 male) who had received a total hip arthroplasty (THA) from a single surgeon from 10/21/2003 to 9/6/2007. No THA candidate was excluded for any reason, including body habitus (mean BMI = 27.7, range 17.5 – 42.3), underlying disease process, age (mean age at surgery = 57, range 27 – 80), sex or side of surgery (21 left THAs, 24 right THAs). According to our standard clinical treatment protocol, each patient had a pre-operative CT scan for CT-based surgical navigation of the hip arthroplasty and each patient had an intraoperative radiograph taken to assess component positioning. All THAs were performed in the lateral decubitus position on a radiolucent peg-board positioning device. Each patient’s intraoperative pelvic radiograph was taken after acetabular component and trial femoral component insertion with the leg placed in a neutral position on the operating table and with the xray plate aligned squarely with the operating table. The orientation of the pelvis on the operating table was calculated by comparing the intraoperative 2D projection to the 3D CT dataset using software that can perform 2D-3D matching (XAlign). This software has been validated previously. By matching the 3D CT dataset to the magnification and orientation of the plain radiograph, the position of the anterior pelvic plane relative to the operating table could be calculated.

Results: The mean pelvic tilt (rotation around the medial-lateral axis) was 6.84 degrees of anterior pelvic tilt (lordosis) with a standard deviation of 7.95 degrees and a range from 27.24 degrees of lordosis to 4.96 degrees of kyphosis. The mean pelvic obliquity (rotation around the longitudinal axis) was 2.89 degrees anterior from neutral with a standard deviation of 9.44 degrees and a range from 29.36 anterior to 16.59 posterior from neutral. The mean pelvic rotation (rotation around the anterior-posterior axis) was 2.56 degrees cephelad, with a standard deviation of 4.10 degrees and a range from 10.88 degrees cephalad to 5.97 degrees caudad. Pearson correlation statistics showed no relation among pelvic position and body mass index or age. A correlation was seen between pelvic obliquity and pelvic rotation.

Conclusion: This study shows a high variability of intraoperative pelvic positioning in the clinical setting using accurate measurement tools. The greatest variation was seen in pelvic obliquity which has the greatest influence on anteversion/retroversion of the acetabular component. Additionally, pelvic obliquity and rotation appear related in our series. Since all of our intraoperative radiographs were taken with the leg in a neutral position, it is likely that the pelvis is even more greatly malpositioned at other times during the surgery when forces applied by retractors or upon the leg may be greater.

INTRODUCTION: Malposition of the pelvis at the time of acetabular component insertion can contribute to malpositioning of the acetabular component. This study measures the variation in intraoperative positioning of the pelvis on the operating table during surgery by matching intraoperative radiographs with pre-operative computed tomograms (CT) using 2D-3D matching.

METHODS: This prospective study was comprised of a random sample of 45 patients (n = 45, 26 female, 19 male) who had received a total hip arthroplasty (THA) from a single surgeon from 10/21/2003 to 9/6/2007. No THA candidate was excluded for any reason, including body habitus (mean BMI = 27.7, range 17.5 – 42.3), underlying disease process, age (mean age at surgery = 57, range 27 – 80), sex or side of surgery (21 left THAs, 24 right THAs). According to our standard clinical treatment protocol, each patient had a pre-operative CT scan for CT-based surgical navigation of the hip arthroplasty and each patient had an intraoperative radiograph taken to assess component positioning. All THAs were performed in the lateral decubitus position on a radiolucent peg-board positioning device. Each patient’s intraoperative pelvic radiograph was taken after acetabular component and trial femoral component insertion with the leg placed in a neutral position on the operating table and with the xray plate aligned squarely with the operating table. The orientation of the pelvis on the operating table was calculated by comparing the intraoperative 2D projection to the 3D CT data-set using software that can perform 2D-3D matching (XAlign). This software has been validated previously. By matching the 3D CT dataset to the magnification and orientation of the plain radiograph, the position of the anterior pelvic plane relative to the operating table could be calculated.

RESULTS: The mean pelvic tilt (rotation around the medial-lateral axis) was 6.84 degrees of anterior pelvic tilt (lordosis) with a standard deviation of 7.95 degrees and a range from 27.24 degrees of lordosis to 4.96 degrees of kyphosis. The mean pelvic obliquity (rotation around the longitudinal axis) was 2.89 degrees anterior from neutral with a standard deviation of 9.44 degrees and a range from 29.36 anterior to 16.59 posterior from neutral. The mean pelvic rotation (rotation around the anterior-posterior axis) was 2.56 degrees cephelad, with a standard deviation of 4.10 degrees and a range from 10.88 degrees cephalad to 5.97 degrees caudad. Pearson correlation statistics showed no relation among pelvic position and body mass index or age. A correlation was seen between pelvic obliquity and pelvic rotation.

CONCLUSION: This study shows a high variability of intraoperative pelvic positioning in the clinical setting using accurate measurement tools. The greatest variation was seen in pelvic obliquity which has the greatest influence on anteversion/retroversion of the acetabular component. Additionally, pelvic obliquity and rotation appear related in our series. Since all of our intraoperative radiographs were taken with the leg in a neutral position, it is likely that the pelvis is even more greatly malpositioned at other times during the surgery when forces applied by retractors or upon the leg may be greater.

Aim: The purpose of this study was to evaluate the success and complication rate of endoscopic carpal tunnel release (ECTR) using the Chow technique in a large series of patients. Methods: Between September 1897 and February 2001, 2402 hands in 1698 patients underwent ECTRusing the Chow technique. The mean age of the patients was 51 years (14–96). The diagnosis of CTS was based on clinical symptoms and nerve conduction velocity test. Patients were evaluated by physical examination or interviewed by telephone for the current status of their hands. Patients were asked to report about any symptoms following surgery, including numbness, tingling, night pain, weakness and if present the severity of them. The return to work status was followed in 1156 patients. Results: The average follow-up was 6 years and 10 months (range 4 to 161 months). The average operating time was 8 minutes (ranged 5 to 27). A total of 2284 (95%) hands were completely asymptomatic or had very minor problems after ECTR. There were 26 complications, including perioperative (neurapraxias) and late (failed cases, recurrences, infections) complications. The overall complication rate was 1.1% but no serious complications were occurred in this series. Ninety percent of non-workerñs compensation patients and 60% of workerñs compensation patients return to work within 4 weeks. Conclusions: This study suggests that ECTR for carpal tunnel syndrome is a reliable procedure with a high success rate. Furthermore, the technique was found to be safe and iatrogenic complications can be avoided with meticulous surgical technique.

Aim: The purpose of this study was to evaluate the results of arthroscopic capsular release in patients with primary adhesive capsulitis of the glenohumeral joint. Methods: Twenty-eight shoulders in 27 patients with adhesive capsulitis of the glenohumeral joint were treated with manipulation and arthroscopic capsular release. Their average age was 54.5 years (range, 39–67). During surgery, synovectomy and a combined anterior, posterior and inferior arthroscopic release using electrocautery or laser was performed. Range of motion and evaluation with the Constant score before and after surgery was performed in all patients. Results: The mean follow-up was 32 months (24–63). The mean Constant score significantly improved from 44.6 (28–52) preoperatively to 86.3 (73–52) postoperatively (p< 0.001, paired t-test). Range of motion for all planes significantly improved. Abduction improved from 72° preoperatively to 165° postoperatively; Internal rotation improved from 13° to 60° and external rotation from 10° to 75°. Subjectively all patients had remarkably less pain, and there were no complications. Conclusions: Our study suggest that arthroscopic treatment of primary adhesive capsulitis with capsular release is an effective and reliable method for restoring a painless motion of the glenohumeral joint.

Aim: The aim of this prospective study was to evaluate the results of arthroscopic treatment of chondral and osteochondral lesions of the knee with osteochondral autogenous transplantation (OAT). Methods: Thirty patients with symtomatic cartilage lesions of the femoral condyles were treated with OAT. Inclusion criteria were full thickness femoral condyle defects between 1 and 3 cm in diameter. Grafts were harvested from the superior intercondylar notch and press þt into holes drilled into the defect starting adjacent to the articular cartilage margin. All patients were evaluated both pre and postop with the Lysholm score, IKDC Form and radiological assessment. Second look arthroscopy was offered to all patients independently of their symptoms. Results: The mean follow-up was 44.7 months. The mean Lysholm score signiþcantly improved from 43.6 pre-operatively to 87.5 postoperatively (p< 0.001, paired t-test) with excellent and good results in 25 (83.3%) patients. Using the IKDC assessment 26 (86.6%) of the patients reported their knee as being normal or nearly normal. Repeat arthroscopies have been done in 9 (30%) patients. Seven of these demonstrated complete healing and two partial healing. The histological examination ascertained the presence of viable chondrocytes and normal hyaline cartilage in the completely healed cases. Conclusions: Our study suggest that arthroscopic OAT is an effective method for treating chondral defects of the femoral condyles in selected cases. However, further studies with long-term follow-up are needed to determine if the transplanted area will maintain functional and structural integrity over time.