Aims. The aims of the study were to report for a cohort aged younger than 40 years: 1) indications for HRA; 2) patient-reported outcomes in terms of the modified Harris Hip Score (HHS); 3) dislocation rate; and 4) revision rate. Methods. This retrospective analysis identified 267 hips from 224 patients who underwent an hip resurfacing arthroplasty (HRA) from a single fellowship-trained surgeon using the direct lateral approach between 2007 and 2019. Inclusion criteria was minimum two-year follow-up, and age younger than 40 years. Patients were followed using a prospectively maintained institutional database. Results. A total of 217 hips (81%) were included for follow-up analysis at a mean of 3.8 years. Of the 23 females who underwent HRA, none were revised, and the median head size was 46 mm (compared to 50 mm for males). The most common indication for HRA was femoroacetabular impingement syndrome (n = 133), and avascular necrosis ( (n = 53). Mean postoperative HHS was 100 at two and five years. No dislocations occurred. A total of four hips (1.8%) required reoperation for resection of heterotopic ossification, removal of components for infection, and subsidence with loosening. The overall revision rate was 0.9%. Conclusion. For younger patients with higher functional expectations and increased lifetime risk for revision, HRA is an excellent bone preserving intervention carrying low complication rates, revision rates, and excellent patient outcomes without lifetime restrictions allowing these patients to return to activity and sport. Thus, in younger male patients with end-stage hip disease and higher demands, referral to a high-volume HRA surgeon should be considered. Cite this article: Bone Jt Open 2023;4(6):408–415

Aims

Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement.

The primary treatment goal for patients with femoroacetabular impingement syndrome, a common hip condition in athletes, is to improve pain and function. In selected patients, in the short term following intervention, arthroscopic hip surgery is superior to a pragmatic NHS- type physiotherapy programme. Here, we report the three-year follow-up results from the FemoroAcetabular Impingement Trial (FAIT), comparing arthroscopic hip surgery with physiotherapy in the management of patients with femoroacetabular impingement (FAI) syndrome. Two-group parallel, assessor-blinded, pragmatic randomised controlled study across seven NHS England sites. 222 participants aged 18 to 60 years with FAI syndrome confirmed clinically and radiologically were randomised (1:1) to receive arthroscopic hip surgery (n = 112) or physiotherapy and activity modification (n = 110). We previously reported on the hip outcome score at eight months. The primary outcome measure of this study was minimum Joint Space Width (mJSW) on Anteroposterior Radiograph at 38 months post randomisation. Secondary outcome measures included the Hip Outcome Score and Scoring Hip Osteoarthritis with MRI (SHOMRI) score. Minimum Joint Space Width data were available for 101 participants (45%) at 38 months post randomisation. Hip outcome score and MRI data were available for 77% and 62% of participants respectively. mJSW was higher in the arthroscopy group (mean (SD) 3.34mm (1.01)) compared to the physiotherapy group (2.99mm (1.33)) at 38 months, p=0.017, however this did not exceed the minimally clinically important difference of 0.48mm. SHOMRI score was significantly lower in the arthroscopy group (mean (SD) 9.22 (11.43)) compared to the physiotherapy group (22.76 (15.26)), p-value <0.001. Hip outcome score was higher in the arthroscopy group (mean (SD) 84.2 (17.4)) compared with the physiotherapy group (74.2 (21.9)), p-value < 0.001). Patients with FAI syndrome treated surgically may experience slowing of osteoarthritisprogression and superior pain and function compared with patients treated non- operatively

Osteochondroplasty procedure for cam deformity provides excellent outcomes on alleviating pain, improving quality of life and clinical function in femoroacetabular impingement syndrome (FAIS) patients. Although medium-term outcomes on gait biomechanics have been reported, it is unclear how it would translate to better hip muscle forces and joint loading in high range of motion tasks. The purpose of this study was to compare the muscle forces and hip joint contact forces (HCF) during a squat task in individuals before and after cam-FAIS surgical correction. Ten cam-FAIS patients prior and 2-years after osteochondroplasty, and 10 BMI- age- and sex-matched healthy control participants (CTRL) underwent 3D motion and ground reaction forces capture while performing a deep squatting task. Muscle and HCF were estimated using musculoskeletal modeling and comparisons were done using statistical parametric mapping (SPM). Postoperatives squatted down with a higher anterior pelvic tilt and higher hip flexion compared with the preoperatives. Preoperative semimembranosus generated lower forces than the two other groups on the squat ascending, with no differences detected between post-ops and CTRLs. Preoperatives also showed reduced forces for the distal, ischial and medial portions of the adductor magnus relative to the CTRLs, which although reduced, still presented differences postoperatively. Preoperative anterior and medial contact forces were significantly lower than the CTRL group during both phases of the squat. Postoperative vertical and medial forces were also lower compared to the CTRLs. However, with higher vertical forces during the ascent phase of the squat compared to the preoperative, the postoperative group, significantly increased its HCF magnitude. A higher anterior pelvic tilt was associated with an innate restoration of the pelvis position, once the cam deformity no longer existed. The increased force of the semimembranosus muscle while ascending the squat generated higher vertical HCF, which also influenced the increased HCF total magnitude. For any tables or figures, please contact the authors directly

Purpose. To determine the differences of biomechanical properties in three conditions including 1) native cam deformity 2) cam deformity with incomplete resection and 3) cam deformity with complete resection. Methods. A cadaveric study was performed using 8 frozen, hemi-pelvises with cam-type deformity (alpha angle >55°) measured on CT scan and an intact labrum. Intraarticular pressure maps were produced for each specimen under the following conditions: 1) native cam deformity, 2) cam deformity with incomplete resection and 3) cam deformity with complete resection. A 5.5-mm burr was used to resect the lateral portion of the cam deformity to a depth of 3–4 mm. The specimen was placed in a custom designed jig in the MTS electromechanical test system to create pressure and area map measurements. In each condition, three biomechanical parameters were obtained including contact pressure, contact area and peak force within a region-of-interest (ROI). Repeated measurements were performed for three times in each condition and the average value of each parameter was used for statistical analysis. ANOVA was used to compare biomechanical parameters between three conditions. Results. Repeated measures ANOVA analysis demonstrated that the pressures averages of hips with complete resection of cam lesions were significantly lower when compared to averages of hips with incomplete femoral cam lesion and intact cam deformity (2.48. +. 0.56 kg/cm. 3. vs 2.32. +. 0.50 kg/cm. 3. vs 2.02. +. 0.54 kg/cm. 3. , respectively; p-value=0.01). Percentage reduction of contact pressure in the complete resection and incomplete resection groups compared to the native CAM deformity groups were 18.49% and 1.58% respectively. There was no statistically significant difference in contact pressures between the incomplete resection and unoperated groups. Contact area and peak force showed no statistically significant differences across three conditions. Conclusion. There are lower intraarticular hip contract pressures in complete resection of the cam lesions when compared to an incomplete resection and intact hip without resection. These observations underscore the importance of ensuring complete resection of femoral cam lesions in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome. For any tables or figures, please contact the authors directly

Purpose. Femoroacetabular impingement syndrome (FAI) is a common cause of hip and groin pain in young adults. Physiotherapy and surgery have both been used to treat FAI syndrome, but there is no robust evidence of comparative effectiveness. UK FASHIoN compared the clinical and cost-effectiveness of arthroscopic hip surgery (HA) versus best conservative care in patients with FAI syndrome. Methods. UK FASHIoN was a pragmatic, multicentre, 2 parallel arm, superiority, randomised controlled trial in patients with FAI syndrome. Eligible patients were over 16 without radiographic signs of osteoarthritis, deemed suitable for arthroscopic FAI surgery. Participants were randomly allocated to HA or Personalised Hip Therapy (PHT - a physiotherapist-led programme comprising 6 to 10 sessions). The primary outcome measure was hip-related quality of life using the patient-reported International Hip Outcome Tool (iHOT-33) at 12 months. Secondary outcomes included EQ5D5L, SF12, adverse events, and cost-effectiveness. Primary analysis compared differences in iHOT-33 scores at 12 months by intention to treat. Results. 348 patients were randomised. Time to surgery was 132 days (SD71) versus 47 days (SD52) to PHT. 92.5% were followed-up at 12 months. Baseline mean iHOT-33 scores were 39.2 (SD21) and 35.6 (SD18) in the surgery and PHT groups, and at 12 months 58.8 (SD27) and 49.7 (SD25) respectively. Mean scores in both groups improved over 12 months, but the mean iHOT-33 score increased more in those allocated to HA than to PHT, with an adjusted mean difference of 6.8 points (95% CI 1.7,12.0 p=0.009). One HA patient developed an infection requiring further surgery. Mean overall costs were £3713 for HA and £1283 for PHT. Conclusions. Hip arthroscopy and best conservative care both led to improved hip-related quality of life in patients with FAI syndrome. At 12-month follow-up, improvement was greater in those allocated to hip arthroscopy

Purpose: The purpose of this study was to examine the arthroscopy findings in the hips of patient with persistent pain after surgical hip dislocation for femoroacetabular impingement syndrome. Type of study: Retrospective, consecutive series of patients. Patients and Methods: Sixteen consecutive patients (6 male/10 female; average age 33,5 years 19–60y) with persistent pain after surgical hip dislocation for the treatment of femoroacetabular impingement were included. At the index surgery, all patients had an osteo-chondroplasty of the head neck junction and a resection of the acetabular rim with reattachment of the labrum in 9 cases. All patients had a preoperative arthro-MRI and were treated with arthroscopy of the hip. Results: At arthroscopy all reattached labra were stable. In the cases without preservation of the labrum, the joint capsule was attached level with the acetabular rim and had important synovitis. All patients had adhesions between the neck of the femur and joint capsule or between labrum and capsule. In 3 patients the arthroscopic procedure was technically limited by massive thickening of the capsule. Overall 75% (12 of 16) patients showed less pain or were pain free. MDA improved from preoperatively 13 to 16 points at last follow up. Conclusions: Persistent pain after surgical dislocation of the hip could result from intraarticular adhesions that can be shown in the MRI. Hip arthroscopy after previous surgery can be demanding due to scarring. If the adhesions can be released good results can be achieved. Hip arthroscopy is a save therapeutical tool to treat patients with intraarticulary adhesions after surgical dislocation of the hip for femoroacetabular impingement

Introduction: The anterior femoroacetabular impingement syndrome has so far been a great unknown in orthopedic surgery. It is typically characterized by pain when the hip is subjected to the flexion – adduction – internal rotation movement. This pain is provoked by the impaction of the head-neck interface on the anterior wall of the acetabulum. The reason for this may be a retroverted acetabulum, an excessively prominent anterosuperior femoral head-neck junction or a combination of both. For many years, patients have been diagnosed with “adductor tendinopathy” or “inguinal herniations”, when in fact they had a coxofemoral problem. Materials and methods: The first 14 cases operated were analyzed; all of them were young patients who played sports regularly. Using the modified Smith-Petersen approach, an osteoplasty was made in order to resect in the anterior wall and the superior walls of the acetabulum – the latter only in part – and the prominent head-neck junction of the femur. The result was an improvement in the joint balance and the disappearance of impingement. Unlike other authors (Ganz, Trousdale), we avoided an osteotomy of the greater trochanter as a surgical approach. Results: In 13 of the first 14 cases operated with the technique described, immediate pain relief was achieved on internal flexorotation. ROM went from −17 ° mean internal rotation (range: −14°–−28°) in one 80 ° flexion to +23° after one month postop (range: 14°–32°). After two months, there were no instances of Trendelemburg sign or osteonecrosis of the femoral head. Conclusions: We should wait to assess the pre-osteoarthritic development of these patients, although their clinical and functional improvement is evident

The pathology of the posterior acetabular legion in femoroacetabular impingement (FAI) syndrome, so called “contre-coup region”, is still unclear. . 18. F-fluoride positron emission tomography (PET) is a functional imaging modality, which reflects the osteoblast activity. Recent technological advances in PET combined with computed tomography (CT) imaging allowed us to obtain detailed 3-dimensional (3D) morphological information. We evaluated the abnormal uptake of . 18. F-fluoride PET/CT on posterior acetabular lesion in FAI syndrome cases. We enrolled forty-one hips from 41 patients who were diagnosed as FAI syndrome and were performed . 18. F-fluoride PET/CT between October 2014 and October 2016. In each hip, the maximum standardized uptake value (SUV. max. ) on the posterior acetabular was measured. The cases were divided into 4 groups; cam-type (11 cases), pincer-type (7), combined-type (11), dysplastic developmental hip (DDH) with cam morphology (12). The average SUV. max. of the pincer-type was significantly smaller than that of the other 3 groups (p < .05). The percentage of the cases with SUV. max. ≥ 6 was 81.8% in cam-type, 28.6% in pincer-type, 90.9% in combined-type, 91.7% in DDH with cam morphology. Furthermore, the average degree of α angle of the cases of SUV. max. ≥ 6 was significantly higher than that of the cases of SUV. max. < 6 (p = .005). Although actual biomechanical mechanism in contre-coup region is still controversial, this result indicated that the cam morphology related to the posterior acetabular lesion with accelerated bone metabolism

Aims

Research on hip biomechanics has analyzed femoroacetabular contact pressures and forces in distinct hip conditions, with different procedures, and used diverse loading and testing conditions. The aim of this scoping review was to identify and summarize the available evidence in the literature for hip contact pressures and force in cadaver and in vivo studies, and how joint loading, labral status, and femoral and acetabular morphology can affect these biomechanical parameters.

Femoroacetabular impingement (FAI) syndrome is one of the significant reasons for hip pain, loss of ROM at hip joint and developing early osteoarthritis at young active adults. FAI is not a new term and it is treated successfully with open surgical techniques. Some disadvantages of open surgical tecniques has lead orthopedists to develop arthroscopic tecniques. At this study, we aimed to assess the effectiveness of arthroscopy at the treatment of FAI. We included 25 patients (19 male, 6 female) and evaluated retrospectively which has gone under arthroscopic surgery for the treatment of FAÄ° at Gulhane Military Medicine Academy, Department of Orthopedics and Traumatology and Ankara Koru Hospital, Department of Orthopedics and Traumatology between January 2009 and May 2012. We have evaluated modified Harris Hip Score and Visual Analogue Score (VAS) preoperatively and postoperatively at all of our patients. Also we have evaluated, hip internal rotation and flexion range of motions clinically. Mean preoperative Harris Hip Score was 68,52 (range 55–76), mean postoperative score was 88,84 (range 72–98). Mean preoperative flexion ROM was 87, 6 (range 80–95) and 108,2 (range 90–120) postoperatively. Also 4,4 (range 0–5) degrees of mean preoperative internal rotation ROM increased to 19,80 range (10–30) degrees postoperatively. Mean preoperative alpha angle was 76,76 (range 60–90) and it was decreased to 41,76 (range 34–48) postoperatively. Mean preoperative visual analog score were decreased from 8, 63 to 2,8 postoperatively. We had to perform o second look arthroscopy to a patient because of inadequate resection. Also femoral neck stres fracture occured at a patient probably due to early weight bearing. Transient sciatic nevre neuropraxy occured at a 3 patients and, transient ankle pain (approximately 6 weeks) had occured at 2 patients due to traction. Loss of sensation has occured at a patient due to lateral femoral cutaneus nevre injury during portal placement. With these results, we assessed that arthroscopic treatment of the FAI syndrome is succesfull with minor complications comperable to open procedures

Objectives

The spinopelvic relationship (including pelvic incidence) has been shown to influence pelvic orientation, but its potential association with femoroacetabular impingement has not been thoroughly explored. The purpose of this study was to prove the hypothesis that decreasing pelvic incidence is associated with increased risk of cam morphology.