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.

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.

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.

Surgical hip dislocation is a reliable approach for treatment of femoral head fractures.

BACKGROUND: Femoral head fractures are rare injuries; incongruency and instability are indications for surgical intervention. Anterior, posterior, and transtrochanteric surgical approaches have been proposed, but the exposure is limited with classical approaches. Surgical hip dislocation allows for a 360° view of the head and may facilitate a reduction in selected head fractures, but to our knowledge, few studies have reported on the results with this technique. We therefore report on the (1) quality of fracture reduction; (2) modified Harris hip score at a minimum of 2 years (mean, 6 years, range, 26-122 months); and (3) frequency of complications, including avascular necrosis (AVN), arthritis development, and heterotopic ossification, in a case series of patients with femoral head fractures treated with this approach. DESCRIPTION OF TECHNIQUE: The procedure involves digastric trochanteric flip osteotomy and safe dislocation of the femoral head, preserving its vessels. Using this technique we are able to reduce all displaced femoral head fractures under direct view. Definitive fixation is performed through this approach with 2.7-mm nonabsorbable screws. The same technique may be used also for Pipkin IV fractures to fix transverse, T-type, posterior wall, or posterior column acetabular fracture. METHODS: Between 2004 and 2011, we used this approach to manage all displaced femoral head fractures in patients younger than 55 years old. A total of 17 patients were thus treated; of those three were lost to followup before 2 years, and one was excluded from study because of severe preoperative neurological impairment, leaving 13 for analysis here. Patient demographic, injury, and surgical variables as well as complications were recorded and retrospectively evaluated. Radiographic outcome was scored according to Matta's criteria on postoperative radiographs. Outcomes were evaluated with the modified Harris hip score. Minimum followup was 24 months (mean, 77 months; SD, 32.8 months). RESULTS: Fracture reduction was anatomic in eight hips and imperfect in five. Mean clinical score was 82 points (SD, 7.7). One patient developed symptomatic femoral head AVN and underwent total hip arthroplasty 4 years after the index procedure; no other patient underwent arthroplasty. Besides this patient, signs of arthritis (Grade I according to Tönnis classification) were found in one patient and heterotopic ossification was recorded in two patients, but neither was symptomatic. CONCLUSIONS: Our experience with surgical dislocation shows clinical results comparable to previously reported outcomes in femoral head fractures treated with common approaches; we also present a similar rate of AVN and a lower rate of posttraumatic arthritis, but a higher risk of heterotopic ossification. Further case-control studies are necessary to confirm these statements. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Anteroinferior acetabular rim damage due to femoroacetabular impingement.

BACKGROUND: The most common location of labral tears and chondral damage in the hip is the anterosuperior region of the acetabulum, which is associated with pain in flexion and rotation. We describe a case series of patients with labral tears, ganglion formation, and chondromalacia isolated to the anteroinferior acetabulum. Clinically, patients had pain in extension and internal rotation. CASE DESCRIPTIONS: Isolated anteroinferior labral hypertrophy and ganglion were first observed in a patient with coxa valga. We retrospectively reviewed clinical and radiographic records and identified nine hips in seven patients with isolated anteroinferior damage. One patient with bilateral valgus femoral head tilt after slipped capital femoral epiphysis (SCFE) had impingement of the anteromedial metaphysis on the acetabulum from 3 to 6 o'clock. Five of seven had valgus neck-shaft angles and all had acetabular anteversion with damage isolated to the anteroinferior acetabular rim. LITERATURE REVIEW: Series on the diagnostic efficacy of MR arthrogram have noted anteroinferior damage adjacent to superior acetabular rim lesions. However, these do not describe isolated anteroinferior rim damage. In addition, available case series of patients with valgus SCFE do not describe a location of impingement or intraarticular damage. PURPOSES AND CLINICAL RELEVANCE: In this small case series of patients with isolated anteroinferior chondrolabral damage, there are two potential causative mechanisms: (1) primary anteroinferior impingement with femoral extension and internal rotation and (2) posterior extraarticular ischiotrochanteric impingement causing secondary anterior instability of the femur. The pathoanatomy appears to be multifactorial, necessitating an individualized treatment approach.

Slipped capital femoral epiphysis: relevant pathophysiological findings with open surgery.

BACKGROUND: Traditionally arthrotomy has rarely been performed during surgery for slipped capital femoral epiphysis (SCFE). As a result, most pathophysiological information about the articular surfaces was derived clinically and radiographically. Novel insights regarding deformity-induced damage and epiphyseal perfusion became available with surgical hip dislocation. QUESTIONS/PURPOSES: We (1) determined the influence of chronicity of prodromal symptoms and severity of SCFE deformity on severity of cartilage damage. (2) In surgically confirmed disconnected epiphyses, we determined the influence of injury and time to surgery on epiphyseal perfusion; and (3) the frequency of new bone at the posterior neck potentially reducing perfusion during epimetaphyseal reduction. METHODS: We reviewed 116 patients with 119 SCFE and available records treated between 1996 and 2011. Acetabular cartilage damage was graded as +/++/+++ in 109 of the 119 hips. Epiphyseal perfusion was determined with laser-Doppler flowmetry at capsulotomy and after reduction. Information about bone at the posterior neck was retrieved from operative reports. RESULTS: Ninety-seven of 109 hips (89%) had documented cartilage damage; severity was not associated with higher slip angle or chronicity; disconnected epiphyses had less damage. Temporary or definitive cessation of perfusion in disconnected epiphyses increased with time to surgery; posterior bone resection improved the perfusion. In one necrosis, the retinaculum was ruptured; two were in the group with the longest time interval. Posterior bone formation is frequent in disconnected epiphyses, even without prodromal periods. CONCLUSIONS: Addressing the cause of cartilage damage (cam impingement) should become an integral part of SCFE surgery. Early surgery for disconnected epiphyses appears to reduce the risk of necrosis. Slip reduction without resection of posterior bone apposition may jeopardize epiphyseal perfusion. LEVEL OF EVIDENCE: Level IV, retrospective case series. See Guidelines for Authors for a complete description of levels of evidence.

Surgical dislocation technique for the treatment of acetabular fractures.

BACKGROUND: Surgical hip dislocation allows for a 360° view of the acetabulum and may facilitate a reduction in selected acetabular fractures. To our knowledge there is no description in the literature of the different techniques used to reduce acetabular fractures through this approach. The aims of this study are to describe a technique of hip surgical dislocation to treat a variety of acetabular fracture patterns and to ascertain the early results with this technique, including the quality of fracture reductions achieved, clinical results, operative time, and complications such as avascular necrosis and heterotopic ossification. DESCRIPTION OF TECHNIQUE: The procedure involves digastric trochanteric flip osteotomy and safe dislocation of the femoral head, preserving its vessels. T-type, transverse fractures alone or associated with posterior wall could be reduced with specific clamps and reduction adequacy can be judged by direct view. Anterior column fixation could be performed with one or two screws; the posterior column could be fixed with a single posterior plate or with two plates if a transverse fracture is associated with a posterior wall fracture. METHODS: Between 2005 and 2011, we used this approach selectively to manage those types of fractures; during the period in question, we treated 312 acetabular fractures surgically, of which 31 (10%) were treated using this approach. Patient demographic, injury, and surgical variables as well as complications were recorded. Outcomes were evaluated with the Merle d'Aubigné and Postel system. Radiographic outcome was scored according to Matta's criteria on postoperative radiographs (AP and Judet views). Minimum followup was 24 months (mean, 43 months; range, 24-87 months). RESULTS: Fracture reduction was defined as anatomic in 65% cases, imperfect in 16%, and poor in 19%. Mean Merle d'Aubigné score was 15 points (out of 18, with higher scores being better). Two patients developed symptomatic femoral head avascular necrosis. CONCLUSIONS: In complex cases, surgical dislocation presents several advantages; a single approach may reduce surgical time, permit direct intraarticular assessment, and facilitate screw placement closer to the articular surface. It also presents several limitations; some difficulties with bone-reduction clamp positioning, limited fixation of the anterior column, and a small risk of greater trochanter malunion.

Femoroacetabular impingement predisposes to traumatic posterior hip dislocation.

BACKGROUND: Traumatic posterior hip dislocation in adults is generally understood to be the result of a high-energy trauma. Aside from reduced femoral antetorsion, morphologic risk factors for dislocation are unknown. We previously noticed that some hips with traumatic posterior dislocations had evidence of morphologic features of femoroacetabular impingement (FAI), therefore, we sought to evaluate that possibility more formally. QUESTIONS/PURPOSES: We asked whether hips with a traumatic posterior hip dislocation present with (1) a cam-type deformity and/or (2) a retroverted acetabulum. METHODS: We retrospectively compared the morphologic features of 53 consecutive hips (53 patients) after traumatic posterior hip dislocation with 85 normal hips (44 patients) based on AP pelvic and crosstable axial radiographs. We measured the axial and the lateral alpha angle for detection of a cam deformity and the crossover sign, ischial spine sign, posterior wall sign, retroversion index, and ratio of anterior to posterior acetabular coverage to describe the acetabular orientation. RESULTS: Hips with traumatic posterior traumatic dislocation were more likely to have cam deformities than were normal hips, in that the hips with dislocation had increased axial and lateral alpha angles. Hips with posterior dislocation also were more likely to be retroverted; dislocated hips had a higher prevalence of a positive crossover sign, ischial spine sign, and posterior wall sign, and they had a higher retroversion index and increased ratio of anterior to posterior acetabular coverage. CONCLUSIONS: Hips with posterior traumatic dislocation typically present with morphologic features of anterior FAI, including a cam-type deformity and retroverted acetabulum. An explanation for these findings could be that the early interaction between the aspherical femoral head and the prominent acetabular rim acts as a fulcrum, perhaps making these hips more susceptible to traumatic dislocation.

Impingement adversely affects 10-year survivorship after periacetabular osteotomy for DDH.

BACKGROUND: Although periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH) provides conceptual advantages compared with other osteotomies and reportedly is associated with joint survivorship of 60% at 20 years, the beneficial effect of proper acetabular reorientation with concomitant arthrotomy and creation of femoral head-neck offset on 10-year hip survivorship remains unclear. QUESTIONS/PURPOSES: We asked the following questions: (1) Does the 10-year survivorship of the hip after PAO improve with proper acetabular reorientation and a spherical femoral head; (2) does the Merle d'Aubigné-Postel score improve; (3) can the progression of osteoarthritis (OA) be slowed; and (4) what factors predict conversion to THA, progression of OA, or a Merle d'Aubigné-Postel score less than 15 points? METHODS: We retrospectively reviewed 147 patients who underwent 165 PAOs for DDH with two matched groups: Group I (proper reorientation and spherical femoral head) and Group II (improper reorientation and aspherical femoral head). We compared the Kaplan-Meier survivorship, Merle d'Aubigné-Postel scores, and progression of OA in both groups. A Cox regression analysis (end points: THA, OA progression, or Merle d'Aubigné-Postel score less than 15) was performed to detect factors predicting failure. The minimum followup was 10 years (median, 11 years; range, 10-14 years). RESULTS: An increased survivorship was found in Group I. The Merle d'Aubigné-Postel score did not differ. Progression of OA in Group I was slower than in Group II. Factors predicting failure included greater age, lower preoperative Merle d'Aubigné-Postel score, and the presence of a Trendelenburg sign, aspherical head, OA, subluxation, postoperative acetabular retroversion, excessive acetabular anteversion, and undercoverage. CONCLUSIONS: Proper acetabular reorientation and the creation of a spherical femoral head improve long-term survivorship and decelerate OA progression in patients with DDH.

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.

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.

Association between cam-type deformities and magnetic resonance imaging-detected structural hip damage: a cross-sectional study in young men.

OBJECTIVE: Femoroacetabular impingement may be a risk factor for hip osteoarthritis in men. An underlying hip deformity of the cam type is common in asymptomatic men with nondysplastic hips. This study was undertaken to examine whether hip deformities of the cam type are associated with signs of hip abnormality, including labral lesions and articular cartilage damage, detectable on magnetic resonance imaging (MRI). METHODS: In this cross-sectional, population-based study in asymptomatic young men, 1,080 subjects underwent clinical examination and completed a self-report questionnaire. Of these subjects, 244 asymptomatic men with a mean age of 19.9 years underwent MRI. All MRIs were read for cam-type deformities, labral lesions, cartilage thickness, and impingement pits. The relationship between cam-type deformities and signs of joint damage were examined using logistic regression models adjusted for age and body mass index. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined. RESULTS: Sixty-seven definite cam-type deformities were detected. These deformities were associated with labral lesions (adjusted OR 2.77 [95% CI 1.31, 5.87]), impingement pits (adjusted OR 2.9 [95% CI 1.43, 5.93]), and labral deformities (adjusted OR 2.45 [95% CI 1.06, 5.66]). The adjusted mean difference in combined anterosuperior femoral and acetabular cartilage thickness was -0.19 mm (95% CI -0.41, 0.02) lower in those with cam-type deformities compared to those without. CONCLUSION: Our findings indicate that the presence of a cam-type deformity is associated with MRI-detected hip damage in asymptomatic young men.

Clinical stability of slipped capital femoral epiphysis does not correlate with intraoperative stability.

BACKGROUND: The most important objective of clinical classifications of slipped capital femoral epiphysis (SCFE) is to identify hips associated with a high risk of avascular necrosis (AVN)--so-called unstable or acute slips; however, closed surgery makes confirmation of physeal stability difficult. Performing the capital realignment procedure in SCFE treatment we observed that clinical estimation of physeal stability did not always correlate with intraoperative findings at open surgery. This motivated us to perform a systematic comparison of the clinical classification systems with the intraoperative observations. QUESTIONS/PURPOSES: We asked: (1) Is the classification of an acute versus chronic slip based on the duration of symptoms sensitive and specific in detecting intraoperative disrupted physes in patients with SCFE? (2) Is the stable/unstable classification system based on clinical symptoms sensitive and specific in detecting intraoperative disrupted physes in patients with SCFE? METHODS: We retrospectively reviewed 82 patients with SCFE treated by open surgery between 1996 and 2009. We classified the clinical stability of all hips using the classifications based on onset of symptoms and on function. We classified intraoperative stability as intact or disrupted. We determined the sensitivity and specificity of two classification systems to determine intraoperative stability. RESULTS: Complete physeal disruption at open surgery was seen in 28 of the 82 hips (34%). With classification as acute, acute-on-chronic, and chronic, the sensitivity for disrupted physes was 82% and the specificity was 44%. With the classification of Loder et al., the values were 39% and 76%, respectively. CONCLUSION: Current clinical classification systems are limited in accurately diagnosing the physeal stability in SCFE. LEVEL OF EVIDENCE: Level III, retrospective diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Surgical technique: The capsular arthroplasty: a useful but abandoned procedure for young patients with developmental dysplasia of the hip.

BACKGROUND: Codivilla in 1901, Hey Groves in 1926, and Colonna in 1932 described similar capsular arthroplasties--wrapping the capsule around the femoral head and reducing into the true acetabulum--to treat completely dislocated hips in children with dysplastic hips. However, these procedures were associated with relatively high rates of necrosis, joint stiffness, and subsequent revision procedures, and with the introduction of THA, the procedure vanished despite some hips with high functional scores over periods of up to 20 years. Dislocated or subluxated hips nonetheless continue to be seen in adolescents and young adults, and survival curves of THA decrease faster for young patients than for patients older than 60 years. Therefore, joint preservation with capsular arthroplasty may be preferable if function can be restored and complication rates reduced. DESCRIPTION OF TECHNIQUE: We describe a one-stage procedure performed with a surgical hip dislocation and capsular arthroplasty. Various additional joint preservation procedures included relative neck lengthening for improved motion clearance and head size reduction, roof augmentation, and femoral shortening/derotation for containment and congruency. METHODS: We retrospectively reviewed nine patients (one male, eight female; age range, 13-25 years) who had such procedures between 1977 and 2010. Function was assessed by the Harris hip score (HHS). Minimum followup was 1 year (median, 2 years; mean, 7.5 years; range, 1-27 years). RESULTS: At latest followup, the mean HHS was 84 (n = 7) (range, 78-94). One patient underwent THA after 27 years. Complications included one deep vein thrombosis and one successfully treated neck fracture. CONCLUSIONS: Our data in these nine patients suggest capsular arthroplasty performed with a surgical hip dislocation and other appropriate adjunctive procedures is useful to treat dislocated hips in young patients with few complications. It may postpone THA. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Joint-preserving surgery improves pain, range of motion, and abductor strength after Legg-Calvé-Perthes disease.

BACKGROUND: Patients after Legg-Calvé-Perthes disease (LCPD) often develop pain, impaired ROM, abductor weakness, and progression of osteoarthritis (OA) in early adulthood. Based on intraoperative observations during surgical hip dislocation, we established an algorithm for more detailed characterization of the underlying pathomorphologies with a proposed joint-preserving surgical treatment. QUESTIONS/PURPOSES: We asked if patients after LCPD treated with our algorithm experienced (1) reduced pain; (2) improved hip function; and/or (3) prevention of OA progression; we then determined (4) the intraoperative damage patterns; (5) the survival of the hip; and (6) factors predicting the need for a conversion to THA; radiographic progression of OA; a Merle d'Aubigné-Postel score below 15 at last followup; and/or the need for revision surgery. METHODS: We retrospectively reviewed 53 patients after LCPD who underwent joint-preserving surgery (40 surgical hip dislocations, eight acetabular osteotomies, four combined procedures, and one intertrochanteric osteotomy). We obtained Merle d'Aubigné-Postel scores to assess pain; OA was assessed using Tönnis grades. Survival and predictive factors were calculated with the univariate Cox regression. Fifty of the 53 patients were evaluated at a minimum of 5.1 years (mean, 8.2 years; range, 5.1-12.8 years). RESULTS: Pain and hip function improved at followup from a median of 4 points to 5 points. The mean increase in Tönnis grades at last followup was 0.3 to 0.8. The survival of surgery at 5 years was 86%; 13 factors related to survival. CONCLUSION: Patients with symptoms resulting from pathomorphologic deformities after LCPD benefit from joint-preserving surgery with specific treatment of individual structural abnormalities.

Surgical technique: Second-generation bone marrow stimulation via surgical dislocation to treat hip cartilage lesions.

BACKGROUND: Compared to knees, hips have more bony constraint and soft tissue coverage. Thus, repair of focal cartilage defects in hips requires more invasive and technically complex surgeries than simple arthroscopy or arthrotomy. Autologous matrix-induced chondrogenesis (AMIC) is a second-generation bone marrow stimulation technique. Improvement in Tegner, Lysholm, International Cartilage Repair Society (ICRS), and Cincinnati scores has been reported at 1 and 2 years after AMIC in knees. AMIC is potentially useful to repair defects in hips, but it is unknown whether it relieves symptoms or results in a durable construct. DESCRIPTION OF TECHNIQUE: A surgical hip dislocation is used to access the defect. This is débrided to stable cartilage shoulders, necrotic bone is removed, and the lesion base is drilled. Autogenous bone graft is used for lesions with bony defects to create a level surface. Fibrin gel and a collagen membrane are placed to stabilize the superclot for fibrocartilage formation. METHODS: We treated six patients with AMIC in the hip between 2009 and 2010. We obtained Oxford Hip and UCLA Activity Scores. Repair quality was assessed on 6-month postoperative MRI using the modified magnetic resonance observation of cartilage repair tissue (MOCART) system. Minimum 1-year followup data were available for four patients (range, 1-2.5 years). RESULTS: Postoperative Oxford Hip Scores ranged from 13 to 17, UCLA Activity Scores ranged from 5 to 10, and MOCART scores ranged from 55 to 75. No complications occurred. CONCLUSIONS: We describe AMIC in the hip. Although these patients had pain relief and improved function, long-term followup is necessary to assess the duration of improvement, durability of repair, and potential for arthrosis. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Arthroscopic appearance and treatment of impingement cysts at femoral head-neck junction.

PURPOSE: To study the arthroscopic appearance and treatment of impingement cysts and to propose their potential intraoperative value for correct femoral osteochondroplasty in femoroacetabular impingement (FAI). METHODS: We performed a single-surgeon, retrospective study of 152 consecutive hip arthroscopies in 141 patients treated for FAI due to cam, localized pincer, or mixed FAI. Radiographic (conventional radiographs and magnetic resonance arthrography) cyst sizes and locations as well as the arthroscopic appearance were recorded. RESULTS: On the preoperative radiographs, impingement cysts were radiographically visible in 18% of treated FAI patients (26 of 141); 15% of these patients (4 of 26) had more than 1 cyst. Age was the only independent predictor of cysts, with a 7-year shift to a mean age of 42 years. The majority of cysts were located in the anterosuperior quadrant of the femoral head-neck junction (93%), the mean diameter of cysts was 7.0 mm, with a range from 3.7 to 15.1 mm. During surgery, only a few were arthroscopically identifiable, with a pit-like (3 of 26) or crater-like appearance (3 of 26) (i.e., surface alterations) for the larger cysts. The majority of cysts (20 of 26) became evident, however, after unroofing of the area of cam FAI. Cysts were associated with labral (25 of 26) and/or chondral lesions (23 of 26). Small cysts were completely removed during femoral osteochondroplasty, whereas larger cysts were only resected until impingement-free range of motion was reached. No neck fractures occurred in this series. CONCLUSIONS: Impingement cysts were present on 1 in 6 radiographs in patients undergoing hip arthroscopy for FAI and were found most commonly in older patients. The cysts predictably occur within the epicenter of the femoral-induced impingement. Whereas surface alterations are rare (6 of 26), the content and base of the unroofed cyst are consistent. Most cysts are completely excised as part of the femoral impingement correction and may be used as a confirmation that arthroscopic cam resection has been performed at the correct site. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Mentoring in complex surgery: minimising the learning curve complications from peri-acetabular osteotomy.

PURPOSE: The aim of this study was to determine whether a complex surgical procedure such as peri-acetabular osteotomy could be safely learnt by using a programme involving mentoring by a distant expert. To determine this, we examined the incidence of intra-operative complications, the acetabulum correction achieved, the late incidence of re-operation and progressive degenerative arthritis. METHODS: Between 1992 and 2004, peri-acetabular osteotomy was performed in 26 hips in 23 patients. The median follow-up was ten (5-17) years. The median age of the patients at operation was 28 (14-41) years. Clinical outcomes were reported and radiographic results were determined by an independent expert. RESULTS: There were no intra-articular osteotomies, sciatic nerve injuries, hingeing deformities or vascular injuries. There was one ischial nonunion. The lateral centre-edge angle improved from a median 4° pre-operatively to 25°. One revision osteotomy, one osteectomy and three total hip replacements were required, two for progression of osteoarthritis. CONCLUSIONS: The programme of mentoring was successful in that there was a low incidence of the major intra-operative complications that are often reported during the learning curve period and the acetabular corrections achieved were similar to the originators.

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.