Management of the young adult hip pathologies is a special entity in orthopaedic surgical practice that needs special emphasis and consideration. A wide range of pathological and traumatic conditions occur in the young adult hip that lead to functional disability and the development of premature osteoarthritis. Proper surgical interference when the hip is still in the pre-arthritic stage restores function to the young hip and protects it from early degenerative changes, and hence the anticipated need for future joint replacement surgery is prevented. Accurate estimation of the biomechanical error combined with careful understanding of the hip joint biology is the cornerstone of success of any hip preservation surgery ever performed to save the young adult hip.

Safe surgical hip dislocation approach was adopted as one of the tools in the hands of the hip preservation surgeon to treat a broad spectrum of intra-articular hip pathologies like Perthes disease and severe forms of slipped capital femoral epiphysis (SCFE). Osteo-chondroplasty at the head-neck junction with relative femoral neck lengthening for Perthes disease, and Subcapital re-orientation of severe SCFE based on its retinacular vascular pedicle are often performed via the surgical hip dislocation approach. The approach is also useful with certain types of acetabular fractures that enables fixation of dual-column fractures via single approach with intra-articular visualization for the accuracy of reduction and hardware placement.

The 4 cm mini-open direct anterior approach is ideal for the surgical treatment of cases with cam and/or pincer types of femoro-acetabular impingement. Peri-articular osteotomies performed either on the acetabular or the femoral sides of the hip joint are extremely useful in the correction of the biomechanical error that led to an existing hip pathology. Periacetabular osteotomies are commonly performed to treat dysplasia of the young hip. Proximal femoral osteotomies are commonly performed to treat a wide range of hip pathologies including non-unions of femoral neck fractures in the young adult.

Correction of the biomechanical error at the proper timing ensures normalization of the hip joint loading conditions and range of motion that leads to reversal of the pathologic process and prevention of osteoarthritis. A hip joint replacement would have an unknown but certainly a finite life, whereas a young hip that has healed after hip preservation surgery would definitely last for a lifetime.

The purpose of this study is to investigate the feasibility of surgical correction of moderate flexion deformity during total knee arthroplasty by recreating the posterior condylar recess following certain sequence of surgical principles without extra-resection of bone from the distal femur or proximal tibia. The hypothesized surgical protocol was applied in 52 consecutive primary TKAs with moderate flexion deformity. Preoperative and residual postoperative flexion deformity was recorded. Intraoperatively, extension and flexion gap widths were recorded before and after surgical correction. Fixed flexion deformity has improved from a preoperative mean value of 24.8±6.4 to a postoperative residual value of 3.2±1.8 (p value < 0.001). Extension and flexion gap widths have increased by a mean value of 3.8±0.4 mm and 4.1±0.7 mm respectively (p value < 0.005). There was no significant difference between the changes in the extension and flexion gaps. The original flexion/extension gap width mismatch (3.2±0.5mm) was compensated for by an upsized femoral component. The statistically significant changes has demonstrated the efficiency of the hypothesized surgical protocol for management of flexion deformity during TKA added to the benefits of bone conservation for future revision surgery, preservation of surface area for collateral attachments, and establishment of the joint line at the correct level.