LESS INVASIVE TOTAL HIP ARTHROPLASTY (LI-THA) – A STUDY OF 1004 PRIMARY THA AND 36 THA-REVISIONS IN MODIFIED TECHNIQUE

Abstract

Aim: Our aim was to reduce the invasiveness of the THA approach in both primary and revision operations, in order to reach a better functional outcome, to facilitate patient’s rehabilitation and to minimize the encountered operation risks such as dislocation. To achieve our goal, we modified the conventional surgical technique by sparing and reconstructing the joint capsule as well as implanting an individually adapted hip ball size.

Material and Methods: The LI-THA differs from the conventional THA in the following aspects:

1. Selecting the most appropriate size of hip ball among a different variety ranging from 28–44 mm in diameter, in order to simulate the size of the resected femur head and increase the joint stability as much as possible.

2. Sparing and completely reconstructing the joint capsule, especially its acetabular origin.

3. Muscular and iliotibial tract incisions are made parallel to the direction of fibres in order to facilitate optimal surgical reconstruction.

4. Small skin incision together with using absorbable subcuticular skin closure technique to reduce postoperative wound complications.

1004 cases of primary THA and 36 cases of THA revision were evaluated after applying the less invasive technique. A questionnaire was designed to evaluate the patient’s satisfaction regarding pain and function, necessary reoperations, complications such as dislocation or wound dehiscence and leg length discrepancy. Additionally, Symptoms and function were assessed by WOMAC Osteoarthritis Index.

Results: 1004 LI-THA and 36 LI-THA revisions were performed over a period of 82 months. 2 cases of early infection and 2 cases of postoperative haematomas needed surgical intervention. One of the two recorded dislocations was a result of excessive sinking of the endoprosthetic stem. Both of which were successfully surgically corrected. The length of stay was 3 days shorter in comparison to the conventional technique.

Conclusion: The LI-THA is a modified conventional method associated with a low complication rate, which can be used in almost all cases of primary THA and most cases of THA revision. Sparing and reconstruction of the joint capsule as well as implanting the largest possible hip ball chosen from different sizes – ranging from 28 to 44 mm – are the most important modifications, which improve the joint stability and indirectly aid the exact reconstruction of leg length. Based on its low complication rate and short length of stay, the LI-THA is both medically and economically recommended.