Addressing intraarticular pathology at the time of anteverting periacetabular osteotomy for acetabular retroversion is associated with better short-term patient-reported outcomes

Periacetabular osteotomy (PAO) is effective in the management of developmental dysplasia of the hip and femoroacetabular impingement secondary to acetabular retroversion. During anteverting PAO for acetabular retroversion, the need for both labral treatment and femoral head–neck junction osteochondroplasty remains equivocal. Accordingly, this study evaluated patient-reported outcome measures (PROM) and reoperation rates after anteverting PAO with or without intraarticular intervention. Cases of anteverting PAO performed at a single institution between November 2009 and January 2016 were retrospectively reviewed. Patients were divided into three groups: no intervention and intraarticular intervention with arthrotomy or arthroscopy. Subsequently, patients were reclassified by the intraarticular procedure performed at surgery into major (labral repair, femoral head–neck osteochondroplasty) and minor (labral debridement, femoral/acetabular chondroplasty) groups. The cohort was 75% female, median age was 19.5 years and mean body mass index was 25.0 kg/m2. Preoperative to postoperative improvement was compared to minimal clinically important differences (MCID) for eight PROM. Patients receiving major interventions exceeded MCID in a greater proportion of PROM compared to minor and no intervention groups (P < 0.007); major or minor interventions did not increase the risk of reoperation over no intervention (P ≥ 0.39). Based on the current data, surgeons performing anteverting PAO for acetabular retroversion should perform arthroscopic or open labral repair and assess for impingement after the correction and perform a head–neck junction osteochondroplasty if indicated.

Mid-term results after in situ pinning and hip arthroscopy for mild slipped capital femoral epiphysis: a minimum five-year follow-up

Purpose In situ pinning of mild slipped capital femoral epiphysis (SCFE) results in an aspherical head–neck junction and arthroscopic osteochondroplasty can successfully correct the head–neck junction. However, whether the correction stays stable over at least five years remains unknown. Methods In a retrospective and consecutive series, 11 patients with a mean age of 12 years (range, 10 years to 15 years) were included. All patients were treated for mild SCFE with in situ pinning and staged hip arthroscopy correcting the head–neck junction. All patients were assessed clinically and radiographically (radiograph and magnetic resonance imaging (MRI)) pre-operatively, 12 weeks and at least five years’ post-operatively. Results The mean range of motion (ROM) for flexion and internal rotation was stable over time with 100° (sd 4) and 21° (sd 6), respectively at the last follow-up. The mean alpha angle decreased from pre-operative 64° (range 61° to 68°) to 12 weeks post-operative 49° (range 46° to 52°; p = 0.001) and stayed stable over time. New superficial cartilage damage on either the acetabular or femoral side was seen in each three patients. Progressive labral degeneration was present in two patients. Conclusion In situ pinning and staged hip arthroscopy for the correction of mild SCFE is safe, restores normal alpha angles and reveals stable morphological correction at mid-term follow-up. Furthermore, the clinical results were excellent with almost normalized internal hip rotation at mid-term follow-up in patients who had reached adulthood. However, there was some joint deterioration, but without negative impact on subjective and clinical outcome after at least five years. Level of evidence IV

The Effect of Resection Size in the Treatment of Cam-Type Femoroacetabular Impingement in the Typical Patient With Hip Arthroscopy: A Biomechanical Analysis

Background: Arthroscopic osteochondroplasty may improve range of motion and relieve pain in patients with symptomatic hip impingement. Femoral neck fracture is a risk of this procedure because of the weakening of the proximal femur. To our knowledge, there are no biomechanical studies in young human cadaveric bone evaluating the effect of osteochondroplasty on femoral neck strength. Purpose/Hypothesis: The purpose was to evaluate loads to fracture in young human cadavers after resection depths of 25% and 40% at the head-neck junction. We hypothesized that both depths will maintain ultimate loads to failure above previously published loads, as well as above physiologic weightbearing loads. Study Design: Descriptive laboratory study. Methods: Cadaveric proximal femoral specimens (6 matched pairs, under the age of 47 years) were divided into 2 groups: 25% or 40% of the diameter at the head-neck junction was resected. The length of the resection was 2 cm and the width of the resection was determined by the length of the anterolateral quadrant at the head-neck junction in all cases. A compressive load was applied directly to the femoral head. Peak load, stiffness, and energy to fracture were compared between groups. Results: The average peak load to fracture after 25% resection (7347 N) was significantly higher than after the 40% resection (5892 N) ( P = .010). The average energy to fracture was also significantly higher in the 25% resection group (30.2 J vs 19.2 J; P = .007). The average stiffness was higher in the 25% group, although not statistically significant ( P = .737). Conclusion: Resection depths of 25% and 40% at the anterolateral quadrant of the femoral head-neck junction may be safe at previously described functional loads such as standing and walking in the age range more typically seen in patients undergoing hip arthroscopy. Loads to fracture were significantly higher than previously reported using older cadaveric specimens. Clinical Relevance: Currently, most surgeons limit weightbearing after femoral osteochondroplasty in part because of risk of femoral neck fracture. Given the higher observed loads to fracture, young patients could possibly bear weight sooner after surgery, although postoperative protocols should be individualized based on patient age, weight, bone density, amount of bone resected, concomitant procedures, and potential compliance with activity restrictions.

Sclerotic lesions of the femoral head–neck junction for diagnosis of femoroacetabular impingement

The morphological characteristics associated with a diagnosis of femoroacetabular impingement (FAI) observed on plain radiographs can also be seen in subjects without hip joint symptoms. Therefore, the purpose of this study was to investigate whether sclerotic lesions on femoral head–neck junction (FHNJ) could be used as a supplemental diagnostic feature. A total of 128 hips from 119 patients (43 male and 76 female) diagnosed with FAI and 24 hips from 21 patients (2 male and 19 female) with other hip pathologies as control were compared in this study. Using standing frog-leg plain radiographs, the prevalence of sclerotic lesions on the FHNJ was established. Additionally, the pixel intensity (PI) of the sclerotic lesions between the FAI and the control groups were quantitatively compared. Sclerotic lesions were present in 96.1% of FAI hips (123 of 128) and only 37.5% of control hips (9 of 24) ( p < 0.05). The ratio of PI in the FAI group was significantly higher (approximately 10%) than in the control group ( p < 0.05). The evaluation of sclerotic lesions may be used as a supplement to aid in the diagnosis of FAI.

The impact of acetabular labral tears on sexual activity in women

A healthy sex-life is an important component of a good quality of life. However, sexual function may be inhibited in women with acetabular labral tears because of the labrum being caught between the femoral head neck junction and the acetabular rim during flexion and/or abduction of the hip. The aim of this article is to quantify the effect that acetabular labral tears may have on the sexual lives of women and to establish the extent to which they may be expected to resolve after arthroscopic intervention. The article also highlights the importance of including questions related to the impact on sexual activity as a routine part of our taking history for a young adult with hip pain, to gain a true appreciation of the impact the symptoms have on the day-to-day lives of our patients.

Pattern of Inflammatory Molecules in Cartilage of the Impingement Zone in FAI Hips Suggests Origin of Hip Degeneration

Objectives: Femoroacetabular impingement (FAI) is considered a common cause of articular cartilage damage and early hip osteoarthritis (OA) in the young-adult patients. Molecular inflammation is believed to be one of the main initiators of hip OA. Matrix metalloproteinase (MMP)-13 and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4 are known to function as extracellular matrix degrading enzymes in OA joints and have been shown to increase during the process of OA onset. Interleukin (IL)-1β is considered one of the key cytokines involved in the pathogenesis of OA. The aim of this study is to characterize inflammation and early OA pathways in cartilage from the head-neck impingement area in patients with symptomatic FAI cam. Methods: Cartilage samples were obtained in the head neck-junction area from 37 patients undergoing hip surgery between May 2017 and July 2018. Nine patients had a clinical diagnosis of FAI cam (FAI cam) and 15 patients presented advanced OA secondary to FAI cam (OA FAI). These cartilage samples were compared to cartilage samples obtained from similar head neck-junction area from 13 patients with advanced OA secondary to developmental dysplasia of the hip with no impingement (OA DDH). Radiographically, the α-angle was utilized to confirm hip impingement. All histological sections were stained with Safranin-O to assess cartilage degeneration. OARSI grade and Mankin score were used to quantify degenerative OA changes. Immunohistochemistry was performed for IL-1β, MMP-13 and ADAMTS-4. Quantification of immunopositive cells was performed in a blinded fashion. One-way analysis of variance with Tukey’s post hoc test was applied to analyze differences between three groups. Results: FAI cam patients were significantly younger than OA FAI patients (p<0.001) and OA DDH patients (p=0.0461) (Table 1). The average α-angle was significantly higher in the FAI cam and OA FAI groups than the OA DDH group (p<0.001). Cartilage samples from the FAI cam and the OA FAI groups showed degenerative changes. The average OARSI grade was significantly (p<0.01) higher in FAI cam (4.0±0.4) and OA FAI (3.6±0.9) compared to OA DDH (2.2±0.6). The average Mankin score was significantly (p<0.001) higher in FAI cam (7.6±1.2) and OA FAI (6.9±1.8) than OA DDH (4.1±0.7). IL-1β was expressed in cartilage samples from all groups, although the pattern varied.IL-1β was expressed mainly in the superficial layer in the OA DDH group but throughout all cartilage layers in the FAI cam and OA FAI groups. The % immunopositive cells were significantly (p<0.001) higher in FAI cam (58.1±8.9) and OA FAI (71.3±12.4) than OA DDH (28.9±6.3). Similar pattern of distribution was observed for MMP-13 (72.7±11.3, 70.2±18.2 vs 38.0±8.6; p<0.001, p<0.001) and ADAMTS-4 (73.1±7.3, 82.0±12.3 vs 45.3±12.7; p<0.001, p<0.001) (Figure 1). Conclusion: Osteoarthritic changes are evident in the cartilage from the head-neck area of patients with FAI cam morphology. Inflammatory molecules were evident in both early and late stages of hip impingement, suggesting the head-neck impingement area is a potential mediator of inflammation and joint degeneration. [Figure: see text][Table: see text]