Reinforcement Ring-Augmented Hip Arthroplasty: A 35-Year Follow-up.

During the late 1980s, techniques were evolving to prevent acetabular component loosening. Inadequate acetabular bone stock further complicated this concern, which was traditionally addressed with cementation and bone grafting during this time period. However, one evolving tactic to address acetabular component loosening in the setting of inadequate acetabular bone stock was to augment bone graft with an acetabular reinforcement ring. In 1963, a 26-year-old, active male sustained a right-sided femoral neck fracture following a skiing accident. He ultimately developed a collapsed femoral head and varus deformity of the femoral neck requiring a total hip arthroplasty with a cemented monoblock femoral component and a polyethylene acetabular component cemented into a reinforcement ring. The initial procedure was performed in 1988, and this prosthesis is still functioning 35 years later and represents one of the longest follow-ups of a patient with a primary total hip arthroplasty with a reinforcement ring.

Bernese periacetabular osteotomy (PAO): from its local inception to its worldwide adoption.

The development of the Bernese periacetabular osteotomy (PAO) is based on a structured approach starting with an analysis of the preexisting procedures to improve the coverage of the femoral head and was followed by a list of additional goals and improvements. Cadaveric dissections with a detailed description of the vascular supply of acetabulum and periacetabular bone set the stage for an intrapelvic approach, which offered the largest acetabular correction possible combined with safe intracapsular access. The final composition of osteotomies required the development of several instruments and cutting devices before the feasibility could be tested on a series of cadaveric hips.While the sequence of the osteotomies remained largely unchanged over time (except for the pubic and ischial osteotomies), several propositions for an easier/less invasive approach have been discussed; some made it into standard practice. Efforts were undertaken to optimize the learning curve and minimize failures using video-clips, hands-on courses, fellowships, publications, and ongoing mentoring programs. In retrospect, with almost 40 years of experience, such efforts have promoted a worldwide adoption of the Bernese periacetabular osteotomy.

Lateral femoral circumflex artery contribution to the articular and periarticular hip circulation: relevance to the anterior hip approach-a cadaveric study.

BACKGROUND: The purpose of this cadaveric study was to anatomically demonstrate the contribution of the lateral femoral circumflex artery (LFCA) to the articular and peri-articular hip circulation with an emphasis on the vascularization of hip abductors specially tensor fasciae latae muscle (TFLM). METHODS AND MATERIALS: Thirty hips from 26 fresh cadavers were dissected after injection of the aorta or common iliac artery by colored silicon, to study the contribution of the LFCA to the articular and periarticular hip circulation. Furthermore, the aorta was injected in another 18 fresh cadavers after unilaterally ligating the ascending branch of the LFCA (a-LFCA) as the vascular pedicle of the TFLM, to evaluate the collateral circulation to the TFLM, if available. RESULTS: In all specimens but one, the a-LFCA was found as the single major vascular pedicle of the TFLM. When ligated, only 4 out of 18 hips demonstrated colored cast vessels in the cut surface of the muscle. The ascending branch had also consistent but variable contribution to the gluteus medius and gluteus minimus muscles in 80% of the hips. Furthermore, the a-LFCA consistently supplied the anterior and anterolateral aspects of the hip capsule. In 35% of hips, the a-LFCA contributed to the femoral head and neck circulation via one or two small anterior retinacular arteries. CONCLUSION: LFCA contribution to the articular and periarticular hip circulation is only delivered by the ascending branch. The TFLM is specially perfused by the a-LFCA; its ligation significantly decreases the muscle perfusion. It is poorly supplied by the collateral circulation.

The modified capsular arthroplasty for young patients with developmental dislocation of the hip.

The present study aimed to investigate the clinical results of the modified Codivilla-Hey Groves-Colonna capsular arthroplasty in the treatment of young patients with developmental dislocation of the hip. We retrospectively evaluated 90 patients (92 hips) who underwent the modified capsular arthroplasty from June 2012 to June 2021. Hips were evaluated using the modified hip Harris score (mHHS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and the 12-item International Hip Outcome Tool (iHOT-12). The Tönnis osteoarthritis grade and the Severin classification system were used to assess the radiographic outcomes. The average age was 15.7 years (range: 8-26 years). The mean pre-operative mHHS, the WOMAC score and the iHOT-12 score were 83.03, 14.05 and 52.79, respectively. The patients were followed for a mean of 41.1 months (range: 12.1-120.9 months). The patients had a mean mHHS of 83.61 (range: 31.2-97), a WOMAC score of 16.41 (range: 0-51) and an iHOT-12 score of 64.81 (range: 12.9-98.2) at the final follow-up. Capsular thickness had a positive predication on the final functional outcomes. The excellent/good rate of radiological reduction was 79.3%. More than 60% of patients had no/slight osteoarthritis. A total of 54 hips (58.7%) had superior radiographic outcomes. The risk factors for inferior radiographic outcomes were capsular quality (odds ratio [OR]: 0.358, 95% confidence interval [CI]: 0.113-0.931) and capsular thickness (OR: 0.265, 95% CI: 0.134-0.525). Joint stiffness was the most common complication (14.1%). We confirmed the efficacy of this procedure in the treatment of developmental hip dislocation. Patients with poor capsular quality are not suitable for this procedure. With suitable selection according to indications, this procedure can restore the hip rotation center with a low incidence of femoral head necrosis or severe osteoarthritis.

Avascular femoral head necrosis in young gymnasts: a pursuit of aetiology and management.

AIMS: Avascular femoral head necrosis in the context of gymnastics is a rare but serious complication, appearing similar to Perthes' disease but occurring later during adolescence. Based on 3D CT animations, we propose repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension and external rotation as a possible cause of direct vascular damage, and subsequent femoral head necrosis in three adolescent female gymnasts we are reporting on. METHODS: Outcome of hip-preserving head reduction osteotomy combined with periacetabular osteotomy was good in one and moderate in the other up to three years after surgery; based on the pronounced hip destruction, the third received initially a total hip arthroplasty. RESULTS: The described pathology is quite devastating, and extensive joint preserving surgery (which has been shown successful in Perthes' cases) was less successful in this patient cohort. CONCLUSION: Supraselective angiography may be helpful to improve pathomechanical understanding and surgical decision making.Cite this article: Bone Jt Open 2022;3(9):666-673.

Surgical Anatomy of the Rectus-Sparing Approach for Periacetabular Osteotomy: A Cadaveric Study.

BACKGROUND: The Bernese periacetabular osteotomy (PAO) is a widely used technique for the management of acetabular dysplasia and other hip deformities in adolescents and young adults. Originally, the approach was described with a release of both origins of the rectus femoris muscle1. In the more recently described rectus-sparing approach, both heads remain attached2,3. It has been proposed that this modification may decrease pain, ease postoperative rehabilitation, and avoid heterotopic ossifications, without limitations of the surgical overview. DESCRIPTION: Both the original and the rectus-sparing approach are modifications of the Smith-Petersen approach. The skin incision and further dissection remain identical in both approaches for the protection of the lateral femoral cutaneous nerve, the osteotomy of the anterior superior iliac spine (or takedown of the inguinal ligament), the exposure of the iliac fossa, and the medial retraction of the abdominal and iliopsoas muscles. In both variants, the further dissection traverses the iliopectineal bursa. In contrast to the original approach, in which the rectus muscle becomes part of the medial flap after releasing both heads, the rectus-sparing approach involves the undetached rectus muscle becoming part of the lateral flap while the medial flap includes the sartorius and iliacus-iliocapsularis muscles. The anterior capsule and deep structures can be accessed through the interval between the rectus femoris and iliopsoas muscles or lateral to the rectus muscle. The remaining surgical steps are again similar in both techniques. According to preference, the surgeon starts with the pubic osteotomy or with the ischial cut first, the latter avoiding additional bleeding from the pubic osteotomy. For the ischial osteotomy, the bone is accessed by making an anteroposterior tunnel between the medial capsule and the iliopsoas tendon anteriorly and between the medial capsule and the obturator externus muscle posteriorly. While the ischial osteotomy is an incomplete separation, the pubic osteotomy is a complete separation. It sections the superior pubic ramus medial to the iliopectineal eminence, in a somewhat oblique fashion. The third and fourth cuts are made in the iliac bone in such a way as to keep the posterior column intact. By connecting the posterior iliac and ischial cuts as the last osteotomy step, the acetabulum is freed and repositioned as needed. The aim of our cadaver dissection is primarily to describe part of the rectus-sparing approach and to test this modification for eventual disadvantages over the classic approach. The remaining steps of the procedure correspond to the approach as described earlier1,4, appreciating that several modifications of the procedure are in use. ALTERNATIVES: Nonsurgical treatment may be an alternative in borderline dysplasia; however, it needs to be reconsidered and eventually changed to surgical treatment when symptoms persist or come back. Other current techniques for surgical treatment of adolescent and adult hip dysplasia include triple and rotational or spherical osteotomies5-7. RATIONALE: The Bernese PAO is performed through a single incision. All cuts are performed from the inner side of the pelvis, avoiding interference with the vascularity of the acetabular and periacetabular bone, which mainly comes from the outside of the pelvis8. The procedure needs minimal hardware for fixation, and partial weight-bearing can be allowed. The PAO provides a wide range of acetabular reorientation options. Wide capsulotomy and intra-articular procedures are possible, as well as additional femoral corrections. Childbirth via natural delivery is possible even after bilateral PAO9. Nerve injuries can be guarded against with careful surgical execution of the osteotomies4.

Femoral neck osteotomy in skeletally mature patients: surgical technique and midterm results.

PURPOSE: Using an extended retinacular flap containing the blood supply for the femoral head, proximal femur osteotomies can be performed at the neck level increasing the potential of correction of complex morphologies. The aim of this study was to analyze the safety, clinical, and radiographic results of this intra-articular surgical technique performed in skeletally mature patients with a minimum follow-up of three years. METHODS: Fourteen symptomatic adult patients (16 hips) with a mean age of 26 years underwent FNO using surgical hip dislocation and an extended soft tissue flap. Radiographs and radial magnetic resonance imaging (MRI) were obtained before and after surgery to evaluate articular congruency, cartilage damage, and morphologic parameters. Clinical functional evaluation was done using the Nonarthritic Hip Score (NAHS), the Hip Outcome Score (HOS), and the modified Harris Hip Score (mHHS). RESULTS: After surgery, no avascular necrosis was observed, and all the osteotomies healed without complication. The initial neck/shaft angle (range 120 to 150°) improved in all cases to a mean value of 130° ± 4.6 (p < 0.001). In eight of nine valgus hips, the high-positioned fovea capitis changed to a normal position after surgery. The NAHS score improved from a mean of 36.5 ± 14.9 to 82.9 ± 13.9 points after surgery (p < 0.001). After surgery, the mean HOS was 87.1 ± 17.6 points, and the mean mHHS was 78.6 ± 17 points. CONCLUSIONS: In this series, femoral neck osteotomy in the adult, although technically more demanding compared with other classic osteotomies, can be considered a safe procedure with considerable potential to correct hip deformities.

The history of femoroacetabular impingement.

AIMS: Femoroacetabular impingement (FAI) describes abnormal bony contact of the proximal femur against the acetabulum. The term was first coined in 1999; however what is often overlooked is that descriptions of the morphology have existed in the literature for centuries. The aim of this paper is to delineate its origins and provide further clarity on FAI to shape future research. METHODS: A non-systematic search on PubMed was performed using keywords such as "impingement" or "tilt deformity" to find early anatomical descriptions of FAI. Relevant references from these primary studies were then followed up. RESULTS: Although FAI has existed for almost 5,000 years, the anatomical study by Henle in 1855 was the first to describe it in the literature. The relevance of the deformity was not appreciated at the time but this triggered the development of further anatomical studies. Parallel to this, Poland performed the first surgical correction of FAI in 1898 and subsequently, descriptions of similar procedures followed. In 1965, Murray outlined radiological evidence of idiopathic cam-type deformities and highlighted its significance. This led to a renewed focus on FAI and eventually, Ganz et al released their seminal paper that has become the foundation of our current understanding of FAI. Since then, there has been an exponential rise in published literature but finding a consensus, especially in the diagnosis of FAI, has proven to be difficult. CONCLUSION: Current research on FAI heavily focuses on new data, but old evidence does exist and studying it could be equally as important in clarifying the aetiology and classification of FAI.Cite this article: Bone Joint Res 2020;9(9):572-577.

Modern Surgical Treatment of Recurrent Posterior Dislocation of the Native Hip.

BACKGROUND: Redislocation of the native hip is rare. An anterior fulcrum between the proximal part of the femur and the pelvis must be present for a posterior dislocation to occur. The purpose of this study is to describe the cases of 9 patients with posterior redislocation or recurrent subluxation of the native hip that was treated with hip preservation surgery. METHODS: We retrospectively identified the cases of 9 patients, from 2 institutions, who had undergone hip preservation surgery for the management of posterior redislocation or recurrent subluxation of the native hip after a dislocation. The mean number of dislocations prior to surgery was 3.2 (range, 1 to 7). Pelvic radiographs were used to classify the acetabular morphology, sufficiency of acetabular containment, and structural anatomy of the proximal part of the femur. Radiographic identification of impinging structures was used to guide surgical treatment, which involved either femoral correction alone or the combination of femoral correction and an anteverting periacetabular osteotomy. RESULTS: At a mean follow-up of 73.8 months (range, 10 to 192 months), there had been no subsequent episodes of dislocation or subluxation in any of the hips treated with correction of the anatomic pivot point. An algorithmic approach is presented. CONCLUSIONS: In patients who have episodes of redislocation or recurrent subluxation of the native hip, the identification of anatomic abnormalities that create a fulcrum between the proximal part of the femur and the pelvis is critical for making appropriate treatment decisions. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Valgus Slipped Capital Femoral Epiphysis: Pathophysiology of Motion and Results of Intracapsular Realignment.

OBJECTIVES: The purpose of this study was to report (1) a different but specific pattern of impingement in hips involved with valgus slipped capital femoral epiphysis (valgus SCFE) and (2) the results of surgical treatment using intracapsular realignment techniques. DESIGN: Case series. SETTING: Multiple academic centers. PATIENTS: Six patients with 8 involved hips referred for valgus alignment of proximal femoral epiphysis (valgus SCFE). INTERVENTION: Intracapsular realignment osteotomy combined with periacetabular osteotomy if needed. MAIN OUTCOME MEASUREMENT: The clinical and radiographical results and pathophysiology of motion. RESULTS: Eight hips in 6 patients were treated with subcapital (5 hips) or femoral neck (3 hips) osteotomy for realignment. The medially prominent metaphysis created an inclusive impingement at the anterior acetabular wall, whereas the high coxa valga favored impacting impingement at the posterior head-neck junction. The mean preoperative epiphyseal-shaft angle of 110.5 (range 90-125 degrees) was reduced to 62 degrees (range 55-70 degrees) postoperatively. At the last follow-up, all but 1 hip were pain-free and impingement-free, with normal range of motion. One hip was replaced after repeated attempts of correction. The overall hip functional result using modified Merle d'Aubigne scoring system was excellent in 5 hips (18-16 points), good in 2 hips (16-15 points), and poor in 1 hip (6 points). CONCLUSIONS: Impingement in valgus SCFE deformity is specific and complex. Anatomical realignment can lead to favorable results by the restoration of normal morphology and impingement-free range of motion. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Technical particularities of joint preserving hip surgery in osteopetrosis.

Proximal femoral fracture and coxarthrosis are the most common orthopaedic problems of osteopetrosis. Fracture fixation is difficult and one-third fail, with total hip replacement as the final solution. There is little reported experience about how to deal with this particular type of bone and what has been published to date is surprisingly non-specific. Corrective osteotomies are mainly undertaken in children for non-union of a fractured femoral neck and/or for coxa vara. However, any information about technical problems and solutions is scarce and barely instructive. Osteotomy experience for osteopetrosis in youngsters and young adults has not been reported. Osteopetrosis bone is characterized by a small tolerance for displacement and by the high friction experienced when penetrating instruments and implants are used. This article describes the risks of hip surgery in the presence of osteopetrosis and also discusses osteotomies around the hip and how to limit any related complications. Four patients, who underwent different types of hip preservation procedure, have been used to illustrate the difficulties that can be encountered. The article also suggests ways to make osteotomies feasible in osteopetrosis bone, even in adults.

Delayed-Onset Sciatic Nerve Palsy After Periacetabular Osteotomy: A Case Report.

CASE: A large surgical correction was required for severe hip dysplasia, which was associated with a delayed-onset sciatic nerve injury in an adolescent patient. A cortical bone spur on the outside of the acetabular fragment produced an indirect injury that became symptomatic during mobilization of the patient. CONCLUSION: The risk of direct injury to the sciatic nerve during a periacetabular osteotomy is quite low when the osteotomy is executed in extension with abduction of the hip and flexion of the knee to reduce tension on the sciatic nerve. Reported injuries have been attributed to direct damage from excessive soft-tissue retraction or during osseous ischial, supra-acetabular, and/or retroacetabular osteotomies.

Arterial Topographic Anatomy Near the Femoral Head-Neck Perforation with Surgical Relevance.

BACKGROUND: Knowledge of the vascular supply of the femoral head is crucial for hip-preserving surgical procedures. The critical area for reshaping cam deformity is at the retinacular vessel penetration, an area with ill-defined topographic anatomy. We performed a cadaver study of the extension of the lateral retinaculum near the head-neck junction, distribution of the arterial vascular foramina, and initial intracapital course of these vessels. METHODS: In 16 fresh proximal parts of the femur without head-neck deformities, the deep branch of the medial femoral circumflex artery was injected with gadolinium for magnetic resonance imaging (MRI) sequences to identify arterial structures. RESULTS: We found a mean number of 4.5 arterial foramina, showing a predominance from 10 to 12 o'clock. The retinaculum extended 20 mm from 1 to 10 o'clock. The surface distance from the cartilage border to the vascular foramina under the synovial fold was 6.5 mm, and the depth from the same cartilage border to the initial intraosseous vessel pathways was 5.3 mm. CONCLUSIONS: The data add further precision to the arterial topography at the retinacular foramina, an area that is crucial for the perfusion of the femoral head. It may overlap with the area of anterolateral cam deformity and plays a role in choosing the cuts for subcapital and intracapital osteotomies. CLINICAL RELEVANCE: The information is taken from normal hips and may not be directly applicable to the deformed hip. Nevertheless, it is a prerequisite for a surgeon to understand the normal anatomy and use those boundaries to prevent mistakes during intra-articular joint-preserving hip surgical procedures.

Recommendations to Reduce Risk of Nerve Injury During Bernese Periacetabular Osteotomy (PAO).

The Bernese periacetabular osteotomy (PAO) is a widely used procedure to reorient a dysplastic acetabulum resulting from developmental dysplasia of the hip, retroversion, protrusio, or some deformities with a traumatic etiology. Throughout the execution, the lateral femoral cutaneous nerve (LFCN) as well as the obturator, femoral, and sciatic nerves can be injured. Injury to 1 of the 3 major nerves is a devastating event for the patient followed by an ill-defined period of hope for nerve recovery and fear of lifelong disability. Surgical experience is an essential factor in reducing the prevalence of nerve injury, whereas proof of the value of intraoperative fluoroscopy and nerve monitoring still must be established. Although it is known that, for example, the ischial cuts of the complex osteotomy place the sciatic nerve at risk, the action causing the nerve injury is rarely clear in the individual situation. The literature has been mostly limited to reports of incidence and offers little analytic information. Through the use of cadaveric dissections, we visualized the possible impacts of the different steps of the procedure on the nerves in their anatomic vicinity, and the present report demonstrates how nerves can be protected with retractor positioning and how lower-limb positioning can lead to nerve relaxation, an important means to avoid mechanical injury. While the frequent injuries of the LFCN are exclusively related to the approach, sciatic nerve injuries are mainly the result of the ischial osteotomy steps and femoral nerve injuries are seen nearly exclusively with the correction of the acetabular fragment. The authors implemented the demonstrated measures for 9 years, during which approximately 800 periacetabular osteotomies resulted in a total of 2 femoral and 2 sciatic nerve lesions-or a nerve injury rate of 0.5%. The nerves injuries resolved within 6 to 9 months in 3 hips, and 1 patient had a definitive foot drop requiring a splint at the time of writing.

Bernese Periacetabular Osteotomy in a Young Adult with an Ipsilateral Renal Transplant: A Case Report.

CASE: An eighteen-year-old woman was referred to our center because of left groin pain and was diagnosed with acetabular dysplasia. The proposed treatment was a Bernese periacetabular osteotomy (PAO). The patient had undergone two renal transplants due to polycystic kidney disease; the current, functional kidney was at the lateral inguinal fossa on the left side. The patient was on chronic immunosuppressants and antihypertensive therapy. CONCLUSION: The present case shows that PAO can be a safe procedure with good outcomes even in patients who have undergone renal transplantation.

Joint Instability After Anatomic Reconstruction of Severe, Chronic Slipped Capital Femoral Epiphysis: A Report of 3 Cases, with High Femoral Anteversion in 1 and Adaptive Acetabular Roof Deformation in 3.

CASES: Joint instability after slipped capital femoral epiphysis (SCFE) reorientation through the physis has been attributed to a combination of capsulotomy and chondrolabral rim damage. We report on 3 hips with severe SCFE with closed physes, in which anatomic correction with femoral neck osteotomy led to joint instability. All 3 had acetabular roof flattening; 1 showed slight additional acetabular retroversion but also increased femoral anteversion. CONCLUSION: We speculate that the slight roof flattening in all 3 cases and/or the high femoral anteversion in 1 case had contributed to joint instability. Femoral derotation osteotomy was performed in 1 and periacetabular osteotomy was performed in 2 for joint restabilization.

The anatomy and function of the obturator externus.

There is limited knowledge regarding the anatomic relationships and functional anatomy of the Obturator Externus muscle (OE). It is described as a muscle which originates from the external bony margin of the obturator foramen with a cylindrical tendon which passes like a sling under the femoral neck and inserts in the trochanteric fossa. The primary aim of this study is to describe the OE morphology and its anatomic relationship to the acetabulum. A secondary aim is to postulate its action. Eighteen fresh human cadaveric hips were dissected to investigate the anatomy of the OE. A plastic model of the pelvis and femur was used to create a string model based on a technique previously described by Beck et al. The plastic model was used to determine the function of the OE.We conclude that the Obturator externus muscle helps to stabilise the head of the femur in the socket. The mechanical model demonstrated that the primary action of the obturator externus muscle was to externally rotate the femur when the hip was in neutral position and flexed at 90°. Its secondary function was as an adductor when the hip was in flexion.