Background

Magnetic resonance arthrography is the current method of choice for investigating patients with a clinical diagnosis of femoroacetabular impingement prior to performing hip arthroscopy. The aim of our study was to assess the efficacy of this investigation by comparing the findings of MR arthrogram with those found at arthroscopy, with reference to labral tears and chondral damage.

The purpose of this study was to investigate whether patients who had had excision of the Ligamentum Teres as part of a surgical hip dislocation for femoro-acetabular impingement exhibited symptoms of acute Ligamentum Teres rupture post-operatively. Recent reports in the literature suggest that injury to the Ligamentum Teres can cause instability, severe pain and inability to walk. We present the results of a postal questionnaire to 217 patients who had undergone open surgical hip dislocation for femoro-acetabular impingement where the LT was excised. This included seven patients who had undergone bilateral surgery. The questionnaire was designed to enquire about specific symptoms attributed to LT injuries in the literature; gross instability, incomplete reduction, inability to bear weight and mechanical symptoms. 161 patients responded (75%), with a total of 168 (75%) questionnaires regarding 224 hips completed. There were 104 females and 64 males. Median age was 34 and median follow-up was 52 months. All patients were found to have cam deformities, 72% (n=121) had associated labral tears. All patients were able to fully weight bear after surgery. 77% experienced no groin pain and 61% experienced no pain on exercise. 35% of patients experienced popping and locking in their operated hip and 24% had subjective feeling of their hip giving way. Oxford Hip scores and Nonarthritic Hip scores improved by 12 and 28 points respectively (n=47). Our results show that the symptoms of pain and instability described with LT pathology can be present but are by no means universal. This leads us to conclude that their symptoms may be attributed to labral pathology which is frequently noted to coexist

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

Perthes disease often leaves young adults with hip joint incongruency due to femoral head asphericity, (extra-articular extrusion and superior flattening). This causes femoro-acetabular impingement, a reduced range of movement and early degenerative change. We report a novel method for restoration of femoral head sphericity and femoro-acetabular congruency. Two males (aged 21 and 22 years) presented with groin pain and severe hip stiffness after childhood Perthes disease. Imaging confirmed characteristic saddle shaped deformities of the femoral head, with cartilage loss overlying a central depression in the superior section of the head. A new method of treatment was proposed. Both cases were treated in the same manner. A surgical dislocation was performed with a trochanteric flip osteotomy. The extra-articular bump was removed with osteotomes and a burr to reduce femoro- acetabular impingement. The sphericity of the femoral head was restored using a HemiCap partial re-surfacing (Arthrosurface, MA, USA). The radius of the implant was selected to match that of the acetabulum. Restoration of the height of the flattened portion of the weight-bearing surface of the femoral head reduces abnormal loading of the acetabular articular cartilage by improving congruency of the joint. Both patients recovered without incident and were mobilised with crutches, restricted to touch weight-bearing for six weeks to protect union of the trochanteric osteotomy. At a minimum of three year follow-up both patients had sustained improved range of movement, pain and Oxford hip score. Repeated imaging shows no evidence of joint space narrowing or loosening at this stage. We conclude that this novel treatment functions well in the short term. Further surveillance is on-going to confirm that this treatment results in improved long term durability of the natural hip joint after Perthes disease

Rotational acetabular osteotomy (RAO) for developmental dysplasia of the hip (DDH) may not restore normal hip range of motion (ROM) due to the inherent deformity of the hip and it may lead to femoro-acetabular impingement. The purpose of this study was to investigate morphological factors of the pelvis and femur influencing on simulated ROM after RAO with a fixed target for femoral head coverage. We retrospectively reviewed CT images of 52 DDHs with an average lateral centre edge angle (CEA) of 7.9° (−12° to 19°). After virtual RAO with 30° of lateral CEA and 55° of anterior CEA producing femoral head coverage similar to that of the normal hips, we measured simulated flexion ROM using pelvic and femoral computer models reconstructed from the CT images. Pelvic sagittal inclination, acetabular anteversion, lateral CEA, femoral neck anteversion, femoral neck shaft angle (FNSA), alpha angle and the position of the anterior inferior iliac spine (AIIS) were investigated as morphological factor. When the most prominent point of the AIIS existed more distally than the cranial tip of the acetabular joint line in a lateral view of the pelvis model in supine position, the subjects were defined as AIIS-Type1; the remaining subjects were defined as Type 2. There were 10 hips with Type 1 and 42 hips with Type 2 AIIS. The Kappa value of inter-observer reproducibility to classify AIIS was 0.82. Multiple regression analyses were performed to analyse the relationship between ROM and the morphological parameters. We also analysed the relationship between the probability of flexion ROM being less than 110° and the factors which influenced on flexion ROM. FNSA and AIIS-Type independently influenced on simulated flexion ROM after RAO (standard regression coefficient: −0.51 and 0.37, respectively. p< 0.001). The multiple correlation coefficient was 0.68. Flexion ROM after RAO with a fixed femoral head coverage similar to that of the normal hips ranged from 95° to 141° with an average of 121°±8°. The probability of ROM being less than 110° was significantly higher in subjects with AIIS-Type 1 than in those with Type 2 (odds ratio: 13.3, p<0.01). It was also significantly higher in subjects with more than 135° of FNSA than in those with less than 135° of FNSA (odds ratio: 9.5, p<0.05). FNSA and the type of AIIS influenced on flexion ROM after RAO with approximately 40° of variation in spite of a fixed target for femoral head coverage. A large FNSA and a distal positioning of AIIS were independently associated with smaller flexion ROM after RAO

Introduction. In recent years, there has been a significant advancement in our understanding of femoro-acetabular impingement and associated labral and chondral pathology. Surgeons worldwide have demonstrated the successful treatment of these lesions via arthroscopic and open techniques. The aim of this study is to validate a simple and reproducible classification system for acetabular chondral lesions. Methods. In our classification system, the acetabulum is first divided into 6 zones as described by Ilizalithurri VM et al [Arthroscopy 24(5) 534-539]. The cartilage is then graded as 0 to 4 as follows: Grade 0 – normal articular cartilage lesions; Grade 1 softening or wave sign; Grade 2 - cleavage lesion; Grade 3 - delamination and Grade 4 –exposed bone. The site of the lesion is further typed as A, B or C based on whether the lesion is 1/3 distance from acetabular rim to cotyloid fossa, 1/3 to 2/3 distance from acetabular rim to cotyloid fossa and > 2/3 distance from acetabular rim to cotyloid fossa. For validating the classification system, six surgeons reviewed 14 hip arthroscopy video clips. All surgeons were provided with written explanation of our classification system. Each surgeon then individually graded the cartilage lesion. A single observer then compared results for observer variability using kappa statistics. Results. We observed a high inter-observer reliability of the classification system with a kappa coefficient of 0.89 (range 0.78 to 0.91) and high intra-observer reliability with a kappa coefficient of 0.91 (range 0.89 to 0.96). In conclusion we have developed a simple reproducible classification system for acetabular cartilage lesions seen at hip arthroscopy

Background. Femoro-acetabular impingement (FAI) is increasingly recognised as a cause of mechanical hip symptoms in sportspersons. In femoro-acetabular impingement abnormal contact occurs between the proximal femur and the acetabular rim during terminal motion of the hip as a result of abnormal morphologic features involving the proximal femur (CAM) or the acetabulum (Pincer) or both (Mixed) leading to lesions of acetabular labrum and the adjacent acetabular cartilage. It is likely that it is a cause of early hip degeneration. Ganz developed a therapeutic procedure involving trochanteric flip osteotomy and dislocation of the hip, and have reported good results. We have developed an arthroscopic technique to reshape the proximal femur and remove prominent antero-superior acetabular rim thereby relieving impingement. Methods. Twelve patients presented with mechanical hip symptoms and had demonstrable cam-type (eight patients) or mixed (four patients) FAI on radially-reconstructed MR arthrography, were treated by arthroscopic femoral osteochondroplasty and acetabular rim resection if indicated. All patients were competing at the highest level in their respective sport (football, rugby and athletics). All patients were followed up and post-operative Non-Arthritic Hip Scores (NAHS, maximum possible score 100) compared with pre-operative NAHS. Results. There were no complications. All patients were asked to be partially weight-bearing with crutches for four weeks and most returned to training within six weeks. All of them returned to competitive sports by 14 weeks. Symptoms improved in all patients, with mean NAHS improving from 72 pre-operatively to 97 at 3 months. Conclusion. Arthroscopic reshaping to relieve FAI is feasible, safe and reliable. However it is technically difficult and time-consuming. The results are comparable to open dislocation and debridement, but avoid the prolonged disability and the complications associated with trochanteric flip osteotomy. This is important in elite athletes as they can return to training and competitive sports much quicker with less morbidity

Introduction:. Femoro-acetabular impingement reduces the range of motion of the hip joint and is thought to contribute to hip osteoarthritis. Surgical treatments attempt to restore hip motion through resection of bone at the head-neck junction. Due to the broad range of morphologies of FAI, the methodology of osteochondroplasty has been difficult to standardize and often results in unexpected outcomes, ranging from minimal improvement in ROM to excessive head resection with loss of cartilage and even neck fracture. In this study we test whether a standardized surgical plan based on a pre-determined resection path can restore normal anatomy and ROM to the CAM-impinging hip. Methods:. Computer models of twelve femora with classic signs of cam-type FAI were reconstructed from CT scans. The femoral shaft and neck were defined with longitudinal axes and the femoral head by a sphere of best fit. Boundaries defining the maximum extent of anterior resection were constructed: (i) superiorly and inferiorly along the anterior femoral neck at 12:30 and 5:30 on the clock face, approximating the locations of the vascularized synovial folds; (ii) around the head-neck junction along the edge of the articular cartilage; and (iii) at the base of the neck, perpendicular to the neck axis, 20–30 mm lateral to the articular edge. All four boundaries were used to form 3 alternative resection surfaces that provided resection depths of 2 mm (small), 4 mm (medium), and 6 mm (large) at the location of the cam lesion. Solid models of each femur after virtual osteochondroplasty were created by Boolean subtraction of each of the resection surfaces from the original femoral model. For each depth of neck resection, we measured the following: (i) alpha angle, (ii) anterior offset of the head-neck junction, and (iii) volume of bone removed. Before and after each resection, we also measured the maximum internal rotation of the hip in 90° flexion and 0° abduction. Results:. The initial alpha angles of the twelve femora averaged 63.8°, with corresponding average anterior head-neck offset of 5.8 mm and average maximum internal rotation of 16.3°. Impingement prevented one specimen from attaining the initial position of 90° flexion and 0° abduction. Implementation of pre-operative plans demonstrated that normal alpha angles (<55°) could be achieved using resection depths of 2 mm, 4 mm, and 6 mm (small: 48.8°, medium: 40.8°, large: 35.3°). The corresponding changes in internal rotation were +7.7° (to 24.0°; p < 0.001), +11.8° (to 28.1°; p < 0.001), and +14.7° (to 31°; p < 0.001), with anterior offsets of 8.0 mm, 9.9 mm, and 11.2 mm, respectively. The corresponding volume of resected bone ranged from 0.57 cm. 3. to 3.20 cm. 3. . Conclusions:. Our study shows that a standardized method of pre-operative planning may enable surgeons to restore normal hip ROM, alpha angles, and anterior offsets through pre-determined bony resection. This method shows how osteochondroplasty can be customized to each deformity, thus removing only the necessary amount of bone to correct each abnormality. We believe implementation of our boundaries and method will enable surgeons to consistently and quantitatively reproduce and teach osteochondroplasty, and that this method is readily adaptable to computerized machining of the femur