In order to release the contracture band completely without damaging normal tissues (such as the sciatic nerve) in the surgical treatment of gluteal muscle contracture (GMC), we tried to display the relationship between normal tissue and contracture bands by magnetic resonance neurography (MRN) images, and to predesign a minimally invasive surgery based on the MRN images in advance. A total of 30 patients (60 hips) were included in this study. MRN scans of the pelvis were performed before surgery. The contracture band shape and external rotation angle (ERA) of the proximal femur were also analyzed. Then, the minimally invasive GMC releasing surgery was performed based on the images and measurements, and during the operation, incision lengths, surgery duration, intraoperative bleeding, and complications were recorded; the time of the first postoperative off-bed activity was also recorded. Furthermore, the patients’ clinical functions were evaluated by means of Hip Outcome Score (HOS) and Ye et al’s objective assessments, respectively.Aims
Methods
Stability in TKR is provided by the prosthesis design, weight bearing, alignment and soft tissue envelope which triggers proprioception and neuromuscular control. For long survivorship, the least constrained design are prefered whenever possible. Today there is a discussion about the best prosthetic femoro-tibial alignment as discussed widely in Europe and more recently by Pagnano. Total knee replacements must be very stable to improve the function and the wear. We certainly performed too many releases in the past and misunderstood some of the fine tuning between posterior structures and collateral ligament frame. Technique in release tends to be more elaborated in order to address sequentially primary and secundary restraints. Release of the lateral structures often created excessive laxity in the past and can be addressed with translocation of the ligaments insertions. In case of elongated collateral structures, preserving the posterior cruciate and reconstruction of the collateral ligament allows use of less constrained prosthesis. In revision arthroplasty, the condition may be even more complex but usually the collateral ligaments may be identified. It is usually possible to find and reconstruct their insertions especially on the femoral side. Sometimes, augmentation will be needed but at the end, there is a good functional collateral ligament frame. Deformities with different soft tissues conditions and with extraarticular components in primary and revision total knee arthroplasty will be reported in severe varus, valgus and stiff knees.
