Complications In Total Hip Replacement in The Beginning of The Learning Curve Using Direct Anterior Approach

Milev R, Stefanov V and Tzachev N

Published on: 2024-09-01

Abstract

Direct anterior approach (DAA) is the most prefered approach to the hip joint performing total hip arthroplasty(THA) in the last decade. It is intramuscular and intranervous approach uses interval superficially between M. tensor fascia lata (innervated by n. gluteus superior) and M. Sartorius (n. femoralis), in depth between m. rectus femoris (n. femoralis) I gluteus medius (n. gluteus superior). Proponents of this approach cite improved recovery times, lower pain levels, improved patient satisfaction as well as improved accuracy on both implant placement/alignment and leg length restoration. A number of variations of the procedure have been described and many authors have published their experiences and technical keys to successfully accomplishing this procedure. Described techniques have been performed using specifically designed instruments and specific fracture tables and intra-operative flouroscopy, however this approach may be performed using a regular table with standard arthroplasty tools with alternative patient positioning and without intraoperative imaging. This review summarizes several aspects of the direct anterior approach for total hip arthroplasty and its comparison to other popular approaches to modern hip replacement. Complications of DAA in THA at the beginning of the learning curve are not an exeption. Our aim is to show all of the complication we had and to prevent as many complications as we can to improve operative technic and surgery outcome in DAA to THA. This can improve surgeon’s learning curve. Complications like iatrogenic injury to the Lateral Femoral Cutaneus Nerve (LCFN), injury to the femoral nerve, postoperative haematoma or active bleading from not ligated(coagulated) Lateral Circumflex Artery (LCA), malposition of the acetabular cup, periprosthetic femur fracture are difficult to treat with slow recovey and may leave the patient not satisfied from the surgery and to discourage surgeon to continue using this approach performing THA.

Keywords

Complications; Direct anterior approach; Total hip replacment; Patient outcome

Introduction

Direct anterior approach (DAA) is the most prefered approach to the hip joint performing total hip arthroplasty (THA) in the last decade. DAA was first described by Carl Hueter in 1881 in his work – “Grundriss der Chirurgie” (The Compendium of Surgery). DAA is populized later in 1917 from Smith-Peterson. In the beginning this approach is used for DDH, fractures of the proximal femur and FAI. The anterior-based incision in DAA utilizes the interval to the hip joint It is intramuscular and intranervous approach uses interval superficially between M. tensor fascia lata (innervated by n. gluteus superior) and M. Sartorius (n. femoralis), in depth between m. rectus femoris (n. femoralis) I gluteus medius (n. gluteus superior). So as a summary DAA is intramuscular and intranervous approach. Light and Keggi published their experience using this approach for hip arthroplasty in 1980, and Judet described the procedure with the use of a fracture table in 1985. Later in 1996 Dr Laude modified fracture table to leg positioner. Originaly approach uses longitudinal skin incision (Fig.5), later it was modified to oblique(vertical), paralel to the inguinal ligament and it is called “bikini” incision. This approach is characterized by less pain, faster recovery with minimal blood loss, with no damage to the muscle and nerves. Anterior access is preferred because the risk of luxation is lower, with no change in gait post-operatively, with a shorter hospital stay.

LFCN is a purely sensory (cutaneous) nerve, part of the lumbar plexus. It does not affect the muscles of the lower limbs. It is formed by the dorsal branches of the second and third lumbar nerves of (L2-L3). It runs from the lateral to the middle part of m. Psoas major and crosses m. Iliacus oblique to anterior superior iliac spine(ASIS). It then passes under the inguinal ligament and along the course of and over the m. Sartorius descends to the thigh, where it divides into two branches - anterior and posterior

The anterior branch becomes superficial about 10 cm from the inguinal ligament, where it divides into two branches that innervate the anterior and lateral parts of the thigh, including the knee. The terminal branches of the nerve often communicate with the anterior cutaneous coons of the n. Femoralis and with infrapatellar branches of n. Saphenus, together forming the "patellar plexus" (Figure 1).

Figure 1

The posterior branch crosses the Fascia lata and divides into small branches that pass to the posterior and lateral surface of the thigh, innervating the skin from the level of the greater trochanter to the middle of the thigh. (Figure 2)

Anatomical variations are observed in 25% of people. The main ones are: early bifurcation, epifascial position of the nerve, inferior-medial direction and exit from the pelvis through the iliac canal.

Figure 2

In 5%, NCFL is not detected. Anatomical variations of the nerve must be taken into account during surgery in order to protect it during surgical dissection of the area.

Second structure that stands in line in DAA is lateral circumflex artery (LCA). LCA after medial circumflex artery (MCA) provides main blood suply to the femoral head. It is usually a branch of the profunda femoris artery, but can be branch directly from the femoral artery and produces three branches. It is mostly distributed to the muscles of the lateral thigh.

Material and Methods

This is a retrospective single-cohort observational single centre and single surgeon study in the beginning of his learning curve. Collected data included age of patient, BMI, ASA score, EBL (estimated blood loss), LOS (length of stay), operating time, and intra/postoperative complications. Only longitudinal skin incision is used by this surgeon and the wound was sutured with non resorvable 0 threads in continius locking manner. Positioning was supine and manipulating the leg intraoperativle with AMIS leg positioner (Figure 3, 4) was used in 21 patients and 5 patients in position of “4”. A standard institution protocol for all patients undergoing THA regardless of surgical approach was used for all patients during the study period. Primary cementless THA components were used with 3 different types of the implants. Study gathers information between 2020 and 2024 and it contains 26 patients undergone THA via DAA. Average follow up is 2 years. Patient are followed in the 2 weeks, 6 weeks, 6 months and 1 year.

Figure 3

Figure 4

Results

Demographics showed a mean age of 59 years (range 31-69); the mean BMI was 29,79 (range 17,6-39,7). Complications in DAA after THA in this study are: iatrogenic injury to the Lateral Femoral Cutaneus Nerve (LCFN)-5, injury to the femoral nerve (1), postoperative haematoma or active bleading from not ligated(coagulated) Lateral Circumflex Artery(LCA)- 1, malposition of the acetabular cup, leading to dislocation -1, periprosthetic femur fracture- 2( in one patient billateraly). In some patient more than one complication were observed.

In 5 patients LCFN damage was diagnosed. One of the patients had Meralgia paresthetica with burning pain in the lateral and anterior thigh, other 4 had numbness (hypostesia) in varying degrees. Reasons for this complication vary from direct cut to postoperative haematoma. LFCN neuropraxia rates range from 67% to 91% in some series with no functional limitations reported by the patients and as measured by the SF-12, WOMAC, UCLA PROM scores. To protect LCFN skin incision is positioned directly over muscle tensor fascia latae, then dividing it’s fascia we continue deeply. This was LCFN leaves medial with muscle sartorius (Figure 5 , 6,7 and 8).

Figure 5

Figure 6

Figure 7

Figure 8

In one patient femoral nerve damage was diagnosed clinicaly with weakness and hypotrophy in muscles in anterior compartment, with later severe osteoporosis of the femur. It was later comfirmed with EMG. Leading cause for this complication is too aggressive manipulation with the leg on the extension leg positioner, and anterior placed hohman retractors.

During the first DAA after we swithced from lateral approach we had acetabular cup malposition, which led to instability and dislocation of the hip joint. Changing position of the patient from lateral approach(lateral) to DAA (supine) misleads and leads to extreme anteversion of the cup.

Only one significant postoperative haematoma was observed in 1 patient and on 2 patients blood transfusion was performed. The reason for haematoma was insuficient coagulation of the LCA, which led to continius bleeding for the 24 hours.

In 1 patient(female) we had periprosthetic fracture of the both femurs, bilateraly (Fig.8). After carefully consideration we confirmed bad implat choice, which was not suitable to the patient’s femur. These fractures were detected intra-operatively and the fixations were performed at the time of the index surgery. None of both THA on this patient went on to require subsequent revision. In the literature There was a significantly higher rate of revision for

PPF for patients undergoing the anterior approach.

Wound complication and deep surgical site infection is paramount in every THA procedure. The literature report conflicting data about the rates of wound complication in DAA; two series report a reoperation rate for wound infection/wound necrosis of 1,6% and 1,4%, respectively for DAA and posterior approach. However, the deep infection rate was comparable to series of alternatives approach (0,8%).

Another study evaluated obesity as a risk factor for wound complication. Obesity has been shown to be a risk factor for wound complication and surgical site infection in THA regardless of approach; the proximity of the anterior skin incision to the inguinal skin crease with overlying abdominal pannus in obese individuals may explain a high rates of reoperation for wound complication in obese patients (BMI > 40)

In our series, wound complications were not reported. All the patients healed primaty without administration of any antibiotics. No deep infection was reported. In all patient decolonisation protocol was used the night and the mornig before surgery.

Conclusion

Complications rate in this study with THA by DAA is comparable to those reported in literature. There remains a significant learning curve associated with the DAA approach due to its recent popularization and lack of significant experience with this technique in residency training programs until the last decade. Changing from lateral approach without proper preparation can lead to malposition of the cup to extreme anteversion. Avoidance of LCFN nerve damage and it’s complication is possible with blunt dissection between the sartorius and tensor fasciae latae, by using a more lateral incision away from the lateral border of the sartorius muscle, careful dissection, and confining the DAA to the area inferior and lateral to the anterior superior iliac spine. It was slight easier to swith from posterior to anterior approach, than in lateral to anterior. The growing emphasis for minimally invasive arthroplasty and improved and expedited functional results make this approach an attractive choice. The low revision rate suggests that DAA is a safe approach for THA.

References

1. Almasi J, Ambrus R, Steno B. Meralgia Paresthetica-An approach specific neurological complication in patients undergoing daa total hip replacement: Anatomical and Clinical Considerations. Life. 2024; 14: 151.

2. Galakatos G. Direct Anterior Total Hip Arthroplasty. Mo Med. 2018; 115: 537-541.

3. DallOca C, Ceccato A, Cresceri M, Scaglia M, Guglielmini M, Pelizzari G, et al. Facing complications of direct anterior approach in total hip arthroplasty during the learning curve. Acta Biomed. 2020; 91:103-109.