Soft tissue restrictors of femoral elevation in direct anterior approach-an anatomic study

First 100 total hip arthroplasties performed by a young surgeon using the direct anterior approach: learning curve and complications

INTRODUCTION

Most of the reported discussions about the learning curve for the direct anterior approach (DAA) in total hip arthroplasty (THA) have been by experienced surgeons. The study's aim was to describe the learning curve, short-term outcomes, complications, and adaptations to the DAA used in the first 100 THA cases experienced by a young surgeon who had received DAA training for trauma surgeries.

MATERIALS AND METHODS

This retrospective study summarizes the first 100 consecutive cases experienced by a young surgeon who performed the unilateral DAA for THA between 2019 and 2021. Cumulative sum (CUSUM) analysis was performed to evaluate the learning curve on the basis of operative time and overall complications. The demographics data, short-term outcomes, and complications of the first 50 and second 50 cases were compared.

RESULTS

The CUSUM curve declined after 49 and 55 cases, measured by operative time and overall complications, respectively. The median operative time (104 vs. 80 min) and intraoperative fluoroscopic time (38 vs. 12 s) increased significantly in the first 50 cases compared with the times in the second 50 cases. Complications tended to occur in the first 50 cases (12% vs. 6%), and the overall rate was 9%. Major complications all occurred in the first 50 cases, with a rate of 4%. Only one case, which involved a complicated periprosthetic fracture around the stem that extended to the tip, required the intervention of a senior surgeon.

CONCLUSIONS

Even after receiving training on the DAA for trauma surgeries, the young surgeon experienced a steep learning curve and more complications in the first 50 cases. The DAA for THA is a technically demanding procedure and may require guidance from an experienced surgeon to manage unexpected complications.

The short external rotators in the anterior approach hip arthroplasty: do the tendons heal or not? A prospective MRI study

INTRODUCTION

Release of some of the short external rotator tendons may be needed in the direct anterior approach (DAA) for Total Hip Arthroplasty (THA). It is unknown if these tendons heal. The purpose of this prospective study is to examine short external rotator tendon healing after release and the associated effect on muscle volume. In addition, we examined the relation with external rotation force and patient reported outcome measures (PROMs).

METHODS

In 21 DAA THA patients, preoperative MRI was compared with postoperative MRI at 6 weeks and 12 months. PROMs and rotation force of both hips were assessed. Tendon integrity and muscle volume of the obturator internus and piriformis were assessed on MRI using dedicated software.

RESULTS

In 5 patients all tendons remained intact, in 4 patients only the conjoined tendon was released and in 12 patients both the conjoined and piriformis were released. Obturator externus remained intact in all patients. In patients with tendon release, mean volume of obturator internus and piriformis muscle decreased 27% (SD 11) and 23% (SD 16) 6 weeks after surgery, respectively. Released tendons and muscle volume loss did not recover 12 months after surgery. We found no relation between tendon release and hip rotation force or PROMs.

CONCLUSIONS

We found absent tendon healing and muscle volume loss when the conjoined or piriformis tendons were released. Although we found no relation between tendon detachment and hip force or PROMs, we have adapted our operative technique to make it more preserving for the piriformis.

Contributions of the ischiofemoral ligament, iliofemoral ligament, and conjoined tendon to hip stability after total hip arthroplasty: A cadaveric study

An adequate soft tissue balance is important in total hip arthroplasty (THA). This study assessed the contribution of the iliofemoral ligament, ischiofemoral ligament, and conjoined tendon to the range of hip rotation after THA and hip stability in response to axial traction. THA was performed in eight fresh-frozen cadaveric specimens via an anterolateral approach using a navigation system. The ischiofemoral ligament, the medial arm of the iliofemoral ligament, and the conjoined tendon were resected in that order. The ranges of external and internal rotation and the amount of movement of the femoral head in response to axial traction were measured with the hip in 10° of extension, the neutral position, and in 10°, 30°, and 60° of flexion. Resection of the medial arm of the iliofemoral ligament significantly increased the range of external rotation in 10° of extension, the neutral position, and in 10°, 30°, and 60° of flexion. The conjoined tendon was the most important inhibitor of internal rotation from 10° of extension to 30° of flexion. Although each single element had a minor role in stabilizing the hip when axial traction was applied, resection of two or more elements significantly affected joint stability. The iliofemoral ligament and conjoined tendon are the main inhibitors of external rotation and internal rotation, respectively, when THA is performed using an anterior or anterolateral approach. Resection of two or more elements could greatly affect hip stability when axial traction is applied.

A standardized soft tissue release technique to lower the risk of greater trochanteric fractures for the anterior approach in total hip arthroplasty

INTRODUCTION

The direct anterior approach (DAA) is suggested to accelerate postoperative recovery and decrease the dislocation risk after primary total hip arthroplasty (THA). However, exposure of the femur can be challenging. Insufficient exposure increases the risk for intraoperative femoral fracture.

MATERIALS AND METHODS

Of 435 consecutive anterior THA, the first 102 consecutive THA in 94 patients were treated with an external rotator tendon "release-on-demand" (RoD). The following 311 consecutive patients (333 THA) underwent routine release of the conjoint tendon (CTR) of its bony insertion on the greater trochanter only. Retrospective analysis recorded trochanteric fractures, intraoperative calcar fractures, postoperative periprosthetic fractures, stem subsidence, ossifications, and dislocations.

RESULTS

Three (2.9%) fractures of the greater trochanter were recorded in the RoD group, but no (0.0%) fractures occurred in the CTR group (p = 0.002). There was no significant difference in the occurrence of intraoperative calcar fractures (0% (RoD) vs. 1.2% (CTR), p = 0.267), postoperative periprosthetic fractures (0% (RoD) vs. 0.3% (CTR), p = 0.560), stem subsidence (2.0% (RoD) vs. 1.2% (CTR), p = 0.565) or ossifications (2.9% (RoD) vs. 1.6% (CTR), p = 0.344) between these groups. There were no dislocations within a minimum 12 months follow-up period.

CONCLUSION

The routine release of the conjoined tendon (CTR group) decreases the shear forces on the tip of the greater trochanter during DAA THA and eliminates the risk of greater trochanter fractures. The routine release of the conjoined tendon did not increase the risk of postoperative dislocations.

MRI Assessment of Muscle Damage After the Posterolateral Versus Direct Anterior Approach for THA (Polada Trial). A Randomized Controlled Trial

BACKGROUND

There is controversy in literature whether the direct anterior approach (DAA) results in less muscle damage compared with the posterolateral approach (PLA) for total hip arthroplasty. The aim of this randomized controlled trial was to assess muscle damage between these two approaches.

METHODS

Forty-six patients were included. Muscle atrophy, determined with the Goutallier classification, and muscle surface of twelve muscles were analyzed on magnetic resonance imaging images made preoperatively and one year postoperatively. Differences in component placement after DAA or PLA were assessed on radiographs. Harris hip scores and Hip disability and Osteoarthritis and Outcome Score were used as functional outcomes.

RESULTS

External rotator musculature was damaged in both approaches. After PLA, the obturator muscles showed significantly more atrophy and a decrease in muscle surface. After DAA, the tensor fascia latae showed an increased muscle atrophy and the psoas muscle showed a decreased muscle surface. An increase in muscle surface was seen for the rectus femoris, sartorius, and quadratus femoris after both approaches. The muscle surface of the gluteus medius and iliacus was also increased after PLA. No difference in muscle atrophy was found between the approaches for these muscles. The inclination angle of the cup in PLA was significantly higher. No differences were found in functional outcomes.

CONCLUSION

Different muscle groups were affected in the two approaches. After PLA, the external rotators were more affected, whereas the tensor fascia latae and psoas muscles were more affected after DAA.

Short stem hip arthroplasty via the minimally invasive direct anterior approach

OBJECTIVE

Tissue-sparing, minimally invasive hip arthroplasty via the direct anterior approach (DAA) using a partially neck-preserving, calcar-guided short stem.

INDICATIONS

Primary and secondary osteoarthritis of the hip due to developmental dysplasia, femoroacetabular impingement, femoral head necrosis or trauma sequelae.

CONTRAINDICATIONS

Severe osteoporosis, active infection, American Society of Anesthesiologists (ASA) > III, large metaphyseal bone defects, severe metaphyseal deformities, Dorr type C femur.

SURGICAL TECHNIQUE

Supine position on a standard operating table without extension device. Classic DAA skin incision or bikini incision distal to the inguinal fold. Blunt dissection entering the Hueter interval. Capsulotomy with capsule preservation or partial capsulectomy. Intraoperatively, it is crucial to adhere to the preoperatively planned angle and height of the femoral neck osteotomy. During femoral head removal and acetabular preparation, care must be taken to avoid iatrogenic damage to the remaining neck. After cup positioning, femoral access is achieved by release of superior capsular structures. During opening of the medullary canal and broaching, femoral torsion and axis have to be taken into account for correct rotational and axial alignment. Femoral broaches are inserted in an ascending series of sizes until the last broach is firmly lodged and is in direct contact with the antero-medial femoral neck cortex. Fluoroscopic control in two planes to check for femoral anatomic and overall offset and assess whether the implant is adequately seated with cortical support at the calcar, the distal lateral and the dorsal cortex. Implantation of the definitive implants, local infiltration analgesia and wound closure.

RESULTS

Between 1/2011 and 12/2016 60 patients (24 female, 36 male; mean age 44 years) were treated with a partially neck-preserving short stem via the described approach. Seven patients underwent a bi-lateral procedure. Thus, 67 procedures were analysed in this retrospective cohort study. Mean follow-up was 70 months (range 28-93). The median Harris Hip Score was 48 (range 11-88) preoperatively and 98 (range 80-100) postoperatively.

CONCLUSION

The minimally invasive implantation of a partially neck-preserving stem via DAA provides a safe technique with good to excellent clinical results in the mid-term.

Anatomic evaluation of the insertional footprints of the iliofemoral and ischiofemoral ligaments: a cadaveric study

Background

An understanding of the insertional footprints of the capsular ligaments of the hip is important for preserving hip function and stability given the increasing number of minimally invasive hip surgeries being performed under a limited surgical view. However, it is difficult to detect these ligaments intraoperatively and many surgeons may not fully appreciate their complex anatomy. The aims of this study were to quantify the proximal and distal footprints of the iliofemoral ligament (ILFL) and ischiofemoral ligament (ISFL) and to estimate the location of the corresponding osseous landmarks on the proximal femur, which can be detected easily during surgery.

Methods

Twelve hip joints from Japanese fresh frozen cadavers were used. All muscle, fascia, nerve tissue, and vessels were removed to expose the intact capsular ligaments of the hip. The length and width of the proximal and distal footprints of the ILFL and ISFL were measured and their relationship to osseous structures was evaluated, including the intertrochanteric line, femoral neck, and lesser trochanter.

Results

The mean length of the distal medial arm of the ILFL footprint was 17.9 mm and the mean width was 9.0 mm. The mean length of the distal lateral arm of the ILFL footprint was 23.0 mm and the mean width was 9.7 mm. For the footprint of the medial arm, the insertion was in the distal third of the intertrochanteric line and that of the lateral arm was in the proximal 42% of this line. The mean distance from the lesser trochanter to the footprint of the medial arm was 24.6 mm. The mean length of the distal ISFL footprint was 11.3 mm and the mean width was 6.9 mm. The footprint of the distal ISFL was located forward of the femoral neck axis in all specimens.

Conclusions

Understanding the size and location of each capsular ligament footprint in relation to an osseous landmark may help surgeons to manage the hip capsule intraoperatively even under a narrow surgical view. The findings of this study underscore the importance of recognizing that the distal ISFL footprint is located relatively forward and very close to the distal lateral arm footprint.