A Novel Minimally Invasive Spherical Periacetabular Osteotomy: Pelvic Ring Preservation and Patient-Specific Osteotomy by Preoperative 3-Dimensional Templating.

BACKGROUND: Spherical periacetabular osteotomy (SPO) is a novel osteotomy involving splitting the teardrop, using patient-specific preoperative planning, and requiring only a 7-cm skin incision. We report preoperative planning methods and short-term results of SPO. METHODS: In preoperative planning, computed tomography (CT) images were imported into 3-dimensional templating software. The radius of the curved chisel was mapped to pass through the teardrop, the infracotyloid groove of the ischium, and the area between the anterior superior iliac spine and the anterior inferior iliac spine. The osteotomy height and the predicted depth of osteotome insertion were measured, and those values were reproduced during surgery. We performed a retrospective analysis of data on 52 consecutive patients (55 hips) with hip dysplasia who underwent SPO and were followed for at least 2 years: 27 hips had Tönnis grade 0, 21 had grade 1, and 7 had grade 2. The mean age at surgery was 38 years (range, 17 to 56 years). The rotated bone fragment and iliac crest were fixed with absorbable screws. Statistical analysis was performed with the paired t test. RESULTS: The mean (range) of the lateral center-edge and sourcil angles were 6.0° (-20° to 18°) and 26.0 (13° to 38°), respectively, before surgery and 30.0° (15° to 43°) and 3.8° (-4° to 27°), respectively, after surgery (p < 0.001). However, 11 hips (20%) showed a loss of correction of bone rotation (<3 mm) or the sourcil angle (<3°). Radiographs showed bone union in all hips within 3 months after the surgery. Early second surgery related to absorbable screws was performed in 2 hips. No patient had required conversion to total hip arthroplasty at the time of writing. Clinical scores were significantly improved at the 2-year follow-up (p < 0.001). Paresthesia of the lateral femoral cutaneous nerve area was very common but had resolved in 92% of the patients at the 2-year follow-up. CONCLUSIONS: SPO is a novel minimally invasive periacetabular osteotomy that has the potential disadvantage of early loss of correction (observed in 20% of the hips in the present study) but may provide the benefit of decreasing the risk of nonunion at the pubis osteotomy site. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Long-Term Outcomes for Cementless Anatomic Femoral Components, Compared by Area of Porous Coating, in Patients Younger Than 50 Years Treated for Hip Dysplasia.

BACKGROUND: We investigated whether the proximal circumferential porous coating of cementless stems would make implant survival of >20 years possible in young patients. METHODS: Data for patients younger than 50 years with hip dysplasia who had an anatomic stem implanted with a proximal porous coating with hydroxyapatite/tricalcium phosphate were reviewed. Noncircumferential porous (non-C-type) stems were used in 17 hips (13 cases), and circumferential porous (C-type) stems were used in 87 hips (68 cases). Acetabular components with conventional polyethylene were used for all hips. The mean ages at surgery for patients with non-C-type stems and those with C-type stems were 43.3 and 44.7 years, respectively. Stems that had not loosened were retained at the time of acetabular revision. The average duration of follow-up for patients with non-C-type stems was 26.9 years and was 22.3 years for those with C-type stems. RESULTS: Mean survival rates as determined by the Kaplan-Meier method were 74.9% at 20 years and 59.9% at 25 years for non-C-type stems and were 100% at 20 years and 94.0% at 25 years for C-type stems. The survivorship for C-type stems was significantly higher than that for non-C-type stems (P < .01). Focal osteolysis in the shoulder of 37 hips with C-type stems suppressed the spread of osteolysis to the distal femur. CONCLUSION: Anatomic femoral stems with a circumferential porous coating provide excellent durability in patients with hip dysplasia who are 50 years of age or younger. LEVEL OF EVIDENCE: Therapeutic Level IV.

Catastrophic failure of cup revision hip arthroplasty due to undiagnosed Paget disease of bone: A case report.

INTRODUCTION: Paget's disease of bone (PDB) is a localized chronic osteopathy, apparently not genetic in origin, and frequently diagnosed from incidental radiographic images. The disease is characterized by deformation, hypervascularity, and structural weakness of the bone and by changes in joint biomechanics. Most cases of PDB can be easily diagnosed from radiographic findings, but monostotic cases may be problematic and require invasive procedures. PRESENTATION OF CASE: A 70-year-old woman had re-revision surgery for early catastrophic failure of an isolated cup revision hip arthroplasty because of undiagnosed PDB 21 years after the primary total hip arthroplasty. To identify the pathomechanism of early failure, we performed bone biopsy on the right iliac crest. Histopathological findings showed a mosaic pattern in the bone characteristic of PDB. Prior to the planned re-revision surgery, we treated the PDB with denosumab until the patient's serum level of alkaline phosphatase (ALP) was within the normal limits. Two months after denosumab treatment, we performed re-revision hip arthroplasty using a structural allograft and a Kerboull-type reinforcement device. DISCUSSION: The delay in correct diagnosis of PDB was associated with the rapid destruction of pelvic bone. The preoperative use of antipagetic medication could decrease the risk of implant loosening and may be warranted to mitigate that risk. CONCLUSION: In patients with a failed arthroplasty, thoughtful evaluation is warranted for preoperative antipagetic medication in order to reduce PDB activity and potentially decrease the risk of implant loosening. This paper offers some steps for such risk reduction in the workup before revision surgery.

Dual mobility acetabular construct with freedom constrained liner for treatment of recurrent dislocations after total hip arthroplasty: A case report and literature review.

INTRODUCTION: Recurrent dislocation after total hip arthroplasty (THA) using the dual mobility cup system can present challenges, while dual-mobility THA bearings can improve stability in both primary and revision total hip arthroplasties. PRESENTATION OF CASE: A 72-year-old woman with a history of schizophrenia underwent a left primary THA using the G7 dual mobility system. Two postoperative posterior dislocations occurred within 2 months post-surgery. The patient underwent revision surgery in which the metal liner and dual mobility head were exchanged using the Freedom constrained liner system without revision of the cup and stem. As of this writing, 28 months after the revision surgery, no further dislocations have occurred. The implants are stable, and the patient has good range of motion. DISCUSSION: Dual-mobility bearings are utilized to improve stability in both primary and revision total hip arthroplasties, but even if the dual mobility system is chosen, it sometimes fails to prevent postoperative dislocation. Although a relatively high failure rate has been reported in THA using the constrained liner system, this patient's clinical course suggests that the G7 Freedom constrained liner system can be an efficacious option for some patients with unstable hip joints who undergo THA using the dual mobility system. CONCLUSION: A modern constrained liner system such as the G7 Freedom liner may provide an improved salvage solution for joint instability in dual mobility THA.

Computed Tomographic Osteolytic Analysis of a First-Generation Remelted Highly Cross-Linked Polyethylene in Total Hip Arthroplasty-At a Minimum of 15-Year Follow-Up.

BACKGROUND: Low polyethylene wear rate and low incidence of osteolysis have been reported after total hip arthroplasty (THA) using first-generation remelted highly cross-linked polyethylene (HXLPE). However, osteolysis has not been evaluated in long-term studies of these patients (15 years or more). The present study assessed computed tomography (CT) images to determine the incidence of osteolysis associated with HXLPE in THA during at least 15 years of follow-up. METHODS: We evaluated 105 primary THAs in 84 patients (77 women and 7 men). Mean follow-up was 15.9 years (range, 15-18 years). All THAs used a Longevity HXLPE liner and a 26-mm zirconia femoral head. Areas of osteolysis were identified from CT images using 3D and multiplanar reconstruction views. RESULTS: CT 3D multiplanar reconstruction images at 15-year follow-up showed no obvious osteolysis in the acetabulum or femur of any patient. No patients developed cup loosening or liner breakage. CONCLUSION: Our study indicates that first-generation remelted HXLPE liners do not increase the risk of osteolysis during 15-year follow-up and suggests that the wear particles from first-generation remelted HXLPE are less biologically active than those generated by conventional polyethylene devices.

Subchondral fracture caused by unevenly stiffened meniscus after radiofrequency-assisted arthroscopic knee meniscectomy: A case report and review of the literature.

INTRODUCTION: Causality for postarthroscopic osteonecrosis of the knee is unknown, and related mechanisms have been poorly characterized. PRESENTATION OF CASE: This report describes a case of a 69-year-old man with subchondral fracture occurring after arthroscopic meniscectomy using a radiofrequency assisted shaver. The patient experienced increasingly intense knee pain 10 months after the meniscectomy. MR imaging revealed postarthroscopic osteonecrosis of the knee in the femoral medial condyle, requiring unicompartmental knee arthroplasty. A mid-coronal cut section of the resected medial femoral condyle showed a linear fracture line parallel to the subchondral bone endplate. Histopathological examination showed prominent callus formation on both sides of the fracture, comprised of reactive woven bone and granulation tissue. The middle portion of the resected medial meniscus was of uneven height, with significant stiffening of the higher side. The stiffened region of the medial meniscus corresponded to the subchondral fracture in the medial femoral condyle. DISCUSSION: The etiology of post-arthroscopic osteonecrosis of the knee is controversial, but it seems possible that altered knee biomechanics after meniscectomy may predispose patients to osteonecrosis. The findings of the current case suggested that uneven stiffening of the meniscus caused concentration of stress that resulted in postarthroscopic subchondral fracture. CONCLUSION: Subchondral insufficiency fracture following arthroscopy may be underdiagnosed. Surgeons need to carefully consider the risk of subchondral fracture following uneven stiffening of the meniscus when to use radiofrequency in the debridement of a torn meniscus.

External iliac vein compression and lower-extremity swelling caused by an iliopectineal ganglion: a case report.

BACKGROUND: A hip joint ganglion is a rare cause of lower-extremity swelling. CASE PRESENTATION: We report a case of a Japanese patient with ganglion of the hip with compression of the external iliac/femoral vein that produced signs and symptoms mimicking those of deep vein thrombosis. CONCLUSIONS: Needle aspiration of the ganglion was performed, and swelling of the lower extremity promptly decreased. At 7.5 years after aspiration, there was no recurrence of swelling of the leg. Although the recurrence rate for ganglions after needle aspiration is high, it is worthwhile trying aspiration first.

Bilateral spontaneous simultaneous femoral neck occult fracture in a middle-aged man due to osteoporosis and vitamin D deficiency osteomalacia: A case report and literature review.

INTRODUCTION: Bilateral stress fracture of the femoral neck is very rarely seen in healthy young patients who are neither athletes nor military recruits. PRESENTATION OF CASE: The present report describes a 51-year-old male patient, not an athlete and with no previous history of disease, who developed bilateral stress fracture of the femoral neck without displacement. DISCUSSION: Simultaneous bilateral femoral neck fracture is a rare injury. In the present case, two factors predisposed to bilateral occult fracture of the femoral neck. The first was osteoporosis due to the patient's smoking and alcohol abuse. The second was vitamin D deficiency osteomalacia associated with inadequate sun exposure. CONCLUSION: All patients who present with spontaneous hip pain should be evaluated for osteoporosis and osteomalacia and assessed for underlying occult fracture if they report groin pain or difficulty in walking, even when findings from plain X-ray are normal, to improve prognosis in this rare and serious condition.

Positive FABER distance test is associated with higher alpha angle in symptomatic patients.

PURPOSE: The purpose of this study was to determine the diagnostic value of the flexion abduction external rotation (FABER) distance test (FDT) for the diagnosis of cam-type femoroacetabular impingement (FAI) as defined by alpha angle. METHODS: For this study, 603 patients with symptomatic, unilateral femoroacetabular impingement were included. Patients with symptoms of hip instability, bilateral symptoms, bilateral surgery, or bilateral alpha angles over 55 were excluded from the analysis. A positive FDT was defined as a difference of 4 cm or more between hips. A pathological cam was defined as an alpha angle of 78° or greater. RESULTS: The average age was 36.4 ± 12 years, with 344 males and 259 females. Faber distance of the injured hip was correlated with age at surgery (rho = 0.148; p < 0.001). Alpha angle on the injured hip was positively correlated with injured hip FABER distance (rho = 0.276; p < 0.001). The average alpha angle in patients with a positive FABER distance test was 74° (SD = 11°) compared to 68° (SD = 8°) in patients with a negative distance test (p = 0.001). The sensitivity of the FDT to diagnose pathological cam was 0.848 (0.79-0.89) with a negative predictive value of 86% (81-90%). CONCLUSION: This study demonstrated that the FABER distance test is correlated with the alpha angle and is a good diagnostic exam for pathological cam-type FAI as defined by and alpha angle equal to or greater than 78°. CLINICAL RELEVANCE: FABER distance test is a simple test that can be used as a screening test to decide if FAI should be suspected and further testing is needed. LEVEL OF EVIDENCE: III.

Inversion of the acetabular labrum causes increased localized contact pressure on the femoral head: a biomechanical study.

PURPOSE: Although studies suggest that subchondral insufficiency fracture of the femoral head may cause rapidly progressive osteoarthritis of the hip, the mechanism of that relationship remains unclear. Our biomechanical study aimed to provide more data in this area by quantifying pressure distribution on the femoral head for normal and inverted hips and by determining the effects of labral inversion on pressure distribution across the joint, focusing on types of fracture under load. METHODS: We tested mid-sized fourth-generation composite femurs at 15° of adduction, and applied 1 mm/min of axial compressive force to the femoral heads until failure. Additionally, single loads (3000 N) were applied using Prescale film to investigate pressure distribution on the femoral head, with or without silicone rubber representing entrapment of an inverted acetabular labrum. RESULTS: In tests with an external load of 3000 N, the mean pressure for 10 × 5 mm of silicone rubber was 11.09 MPa, significantly greater (about 5.7-fold) than 1.94 MPa without silicone rubber. Different fracture patterns were observed with and without the 10 × 5 mm silicone rubber; when the 10 × 5 mm silicone rubber specimens were used, all eight cases showed fractures in the anterior femoral head. CONCLUSIONS: When silicone rubber representing an inverted acetabular labrum was placed between a hemispherical metallic platen and a composite bone model, the silicone rubber areas were subjected to extreme concentration of stress. The fractures that developed at the silicone rubber areas clearly represented subchondral fractures of the femoral head, rather than fractures of the femoral neck.

Developmental Dysplasia Treated With Cementless Total Hip Arthroplasty Utilizing High Hip Center Reconstruction: A Minimum 13-Year Follow-up Study.

BACKGROUND: The primary aim of this study was to determine the clinical outcomes at 13-year follow-up of patients diagnosed with developmental dysplasia of the hip and subsequently treated with total hip arthroplasty (THA). The secondary aim was to investigate the effect of hip center location on clinical outcomes and polyethylene wear. METHODS: We reviewed data from a consecutive series of 104 patients (123 hips) from a single center. Patients were treated with THA with the high hip center (HHC) technique using cementless acetabular shells and highly cross-linked liners. Radiographs were collected preoperatively and through 13-year follow-up to assess degree of dysplasia (Crowe classification), component positioning, occurrence of bone resorption, and polyethylene wear. The Harris Hip Score (HHS) was administered at 4 and 13 years. RESULTS: No patients were lost to follow-up, and one was revised for femoral loosening. Radiolucency was seen in 20% of patients and was not associated with HHC (P = .560). No patients developed osteolysis. The wear rate was low for all patients (mean: 3 ± 19 µm/y) and not associated with HHC (P = .852). The median 13-year HHS was 91.9 (interquartile range: 84.8-97.0). There was a statistically significant decline from the 4- to 13-year HHS (P < .001) for the Crowe II-IV group, although 82% of these patients remained above 80 points at 13 years. The nondysplastic and Crowe I group showed no longitudinal change in HHS (P = .243). CONCLUSION: This cup design and highly cross-linked polyethylene liner combination demonstrates excellent clinical outcomes, similar to THA for primary osteoarthritis, through 13-year follow-up in patients with various degrees of developmental dysplasia of the hip and HHC reconstructions.

Re-dislocation after revision total hip arthroplasty for recurrent dislocation: a multicentre study.

PURPOSE: Although most case of dislocations after total hip arthroplasty (THA) can be managed with conservative treatment, recurrent dislocation may require surgical intervention. This multicentre study was conducted to evaluate the re-dislocation rate after revision THA for recurrent dislocation, and to determine the risk factors for re-dislocation. METHODS: We retrospectively reviewed the 88 hips in 88 patients who underwent revision THA for recurrent dislocation at five institutions between 1995 and 2014. The mean patient age at surgery was 68.5 years and the mean follow-up period was 53.1 months. Multivariate logistic regression was performed to identify risk factors for re-dislocation. RESULTS: Sixteen hips in 16 patients (18.2 %) re-dislocated at a mean of 25.5 months (range, 1-83 months) after revision THA. Multivariate analysis identified osteonecrosis of the femoral head (odds ratio [OR] = 5.62 vs. osteoarthritis) and a femoral head size < 32 mm (OR = 3.86) as independent risk factors for re-dislocation. Eight hips required additional revision THA for re-dislocation. CONCLUSION: The re-dislocation rate after revision THA for recurrent dislocation remains high, suggesting the need for prevention measures. We recommend the use of a femoral head size ≥ 32 mm.

Should well-fixed uncemented femoral components be revised in infected hip arthroplasty? Report of five trial cases.

BACKGROUND: Well-fixed femoral component removal remains difficult and complicated. METHODS: We report herein the outcomes of two-stage surgery involving retention of bone-ingrown uncemented stems, aggressive soft-tissue debridement, and delayed reimplantation of an acetabular component in 5 patients for infected hip arthroplasty. RESULTS: By a mean follow-up point of 4.2 years after the second-stage operation, none of the 5 patients experienced recurrence of infection, and the mean Harris hip score had improved from 63 to 86 points by the latest follow-up evaluation. CONCLUSION: Two-stage revision with retention of well-fixed uncemented stems could be an alternative treatment option in hip periprosthetic infection.

Tenosynovial giant cell tumors in unusual locations detected by positron emission tomography imaging confused with malignant tumors: report of two cases.

BACKGROUND: A tenosynovial giant cell tumor (T-GCT) is a benign synovial tumor arising from the synovium, bursae, or tendon sheath. It can be intra- or extra-articular and localized or diffuse. Diffuse T-GCT is considered as a locally aggressive. Positron emission tomography (PET) with fluorine-18 fluorodeoxyglucose with computed tomography (FDG PET/CT) is widely used to differentiate malignant from benign tumors and to detect distant metastasis. However, FDG PET/CT is limited by false-positive findings. In this study, we present two cases of T-GCT that developed in unusual locations and were confused with malignant tumors. The final diagnoses were histologically confirmed as T-GCTs. CASE PRESENTATION: Case 1. A 45-year-old Japanese female presented with a left choroidal melanoma and an abnormal lesion adjacent to the first cervical (C1) lamina confirmed by a PET scan (maximum standardized uptake value [SUVmax] =9.9 g/ml). MRI of the neck also detected a soft tissue mass (14.6 × 7.7 × 7 mm) adjacent to the C1 lamina. The choroidal melanoma was treated by heavy carbon ion radiotherapy. Although the size of the C1 soft tissue tumor remained unchanged, a CT-guided biopsy confirmed the diagnosis of the neck mass as a T-GCT. Case 2. A 15-year-old Japanese male with multiple type 1 neurofibromatosis presented with a soft tissue mass (26.1 × 24.7 × 11.5 mm) of the extra-articular hip joint that was coincidentally detected by FDG PET/CT during examination of a mediastinal soft tissue mass. SUVmax of the mediastinal lesion was 2.6 g/ml and of the hip lesion was 12.8 g/ml. Thus, differentiation from a malignant tumor, such as a malignant peripheral nerve sheath tumor, was necessary. An open biopsy was performed, and the frozen section was diagnosed as T-GCT. The tumor was excised, and the final histological diagnosis confirmed T-GCT. CONCLUSION: T-GCT can show high FDG uptake, which might be confused with malignancy. Although MRI findings and location might help in the diagnosis of a T-GCT, careful assessment is mandatory, especially in unusual locations.

Squeaking and microcracks in a delta-delta ceramic coupling: pin-on-disc study.

There is a rising concern about squeaking in ceramic-on-ceramic total hip arthroplasty (THA). In pin-on-disc testing of a delta-delta coupling, we reproduced squeaking and observed microcracks on worn surfaces. We used a pin-on-disc machine and made discs and pins by cutting delta ceramic to a diameter of 40 mm (D-D). Cross-linked polyethylene was used for a comparison disc (D-P). We performed the same test using another D-D coupling specimen to confirm reproducibility. Squeaking in the D-D specimen was reproduced in wet conditions, though it was not found in the D-P specimen. Fast Fourier transform analysis showed a peak frequency for squeaking of 2794 Hz. The noise occurred at about 6.6 km of sliding distance. Scanning electron microscopy revealed that the worn surface of the pin in D-D at 10.8 km of sliding distance had some microcracks. However, there was no obvious damage to the worn surface of the pin in D-P at the same sliding distance. We confirmed the reproducibility of these findings, obtaining similar results, including squeaking, from another D-D coupling specimen. Our findings show that squeaking may occur in THA using delta ceramic bearings even if implants are placed to avoid extra-articular impingement of the femoral neck. Although the clinical relevance of microcracks is unknown, they may affect long-term outcomes in THA using delta ceramic bearings.

Arthroscopic correction for concomitant cam impingement in a patient with idiopathic osteonecrosis of the femoral head: A case report.

A 53-year-old man presented with pain in the right hip. Radiological examination showed idiopathic osteonecrosis of the femoral head (ONFH) combined with a cam lesion. Findings on physical examination were consistent for femoroacetabular impingement. At surgery, we performed isolated arthroscopic correction for the cam lesion but did not use other treatment options such as hip arthroplasty or osteotomies for the ONFH. At the latest follow-up evaluation 3 years after surgery, findings indicted a satisfactory outcome, with a Harris hip score of 93.2 (compared with 76.4 before surgery), no joint-space narrowing, and no collapse of the femoral head. It is important to accurately diagnose the status of idiopathic ONFH and to consider another possible pathogenesis when a patient with idiopathic ONFH has hip pain even without femoral-head collapse.

Occult fracture of the femoral neck associated with extensive osteonecrosis of the femoral head: A case report.

INTRODUCTION: Although the subchondral portion of the femoral head is a common site for collapse in osteonecrosis of the femoral head (ONFH), femoral-neck fracture rarely occurs during the course of ONFH. We report a case of occult insufficiency fracture of the femoral neck without conditions predisposing to insufficiency fractures, occurring in association with ONFH. PRESENTATION OF CASE: We report a case of occult fracture of the femoral neck due to extensive ONFH in a 60-year-old man. No abnormal findings suggestive of ONFH were identified on radiographs, and the fracture occurred spontaneously without any trauma or unusual increase in activity. The patient's medical history, age, and good bone quality suggested ONFH as a possible underlying cause. Contrast-enhanced magnetic resonance imaging was useful in determining whether the fracture was caused by ONFH or was instead a simple insufficiency fracture caused by steroid use. DISCUSSION: The patient was treated with bipolar hemiarthroplasty, but if we had not suspected ONFH as a predisposing condition, the undisplaced fracture might have been treated by osteosynthesis, and this would have led to nonunion or collapse of the femoral head. To avoid providing improper treatment, clinicians should consider ONFH as a predisposing factor in pathologic fractures of the femoral neck. CONCLUSION: ONFH should be included in the differential diagnosis of insufficiency fracture of the femoral neck.

Outcomes After Labral Repair in Patients With Femoroacetabular Impingement and Borderline Dysplasia.

PURPOSE: To determine outcomes after labral repair in patients with borderline dysplasia and femoroacetabular impingement (FAI). METHODS: Patients with dysplasia treated between June 2005 and March 2009 were identified. The study included only patients aged 18 years or older (mean, 35 years; range, 18 to 69 years) whose affected hip had a Wiberg center-edge angle of 20° to 25° and who underwent primary hip arthroscopy performed by the senior author. RESULTS: One hundred two hips (100 patients, comprising 50 women and 50 men) underwent hip arthroscopy with labral repair with correction of FAI and capsular closure. Five hips were converted to total hip arthroplasty, and 7 required revision arthroscopy. Of 95 patients (representing 100 hips, 5 of which underwent total hip arthroplasty), 80 were monitored for a minimum of 2 years. At a mean follow-up point of 40 months, the preoperative modified Harris Hip Score had improved from a mean of 63.5 points (range, 20 to 98 points) to a mean of 84.9 points (range, 45 to 100 points) by the latest follow-up (P < .001). The mean score on the Western Ontario and McMaster Universities Arthritis Index improved from 25.3 (range, 0 to 60) to 9.7 (range, 0 to 59) (P < .001). The 12-Item Short Form Health Survey Physical Component Summary score also significantly improved (from 42.5 to 50.9, P = .001), whereas the 12-Item Short Form Health Survey Mental Health Component Summary score showed an insignificant improvement (from 52.4 to 54.1). CONCLUSIONS: This study showed that FAI and labral pathology can be successfully managed using hip arthroscopy, with capsular management, in patients with borderline dysplasia. Patients showed significant improvements in outcomes and high levels of satisfaction after hip arthroscopy. The need for subsequent procedures was similar to that in patients with just FAI and labral repair. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Arthroscopic capsule reconstruction in the hip using iliotibial band allograft.

The hip capsule has been identified as an important static stabilizer of the hip joint. Despite the intrinsic bony stability of the hip socket, the capsule plays a key role in hip stability, particularly at the extremes of motion, and the iliofemoral ligament is the most important stabilizer in extension and external rotation. Patients who do not undergo capsular closure or plication may continue to complain of hip pain and dysfunction postoperatively, likely because of microinstability or muscle invagination into the capsular defect, and high-resolution magnetic resonance imaging or magnetic resonance arthrography will identify the capsular defect. Seen primarily in the revision setting, capsular defects can cause recurrent stress at the chondrolabral junction. An attempt at secondary closure can be challenging because of capsular limb adherence to the surrounding soft tissues. Therefore reconstruction may be the only possible surgical solution for this problem. We describe our new surgical technique for arthroscopic hip capsular reconstruction using iliotibial band allograft.

Rotational Acetabular Osteotomy for Osteoarthritis with Acetabular Dysplasia: Conversion Rate to Total Hip Arthroplasty within Twenty Years and Osteoarthritis Progression After a Minimum of Twenty Years.

BACKGROUND: We investigated the rate of conversion to total hip arthroplasty by twenty years and radiographic findings at a minimum of twenty years after rotational acetabular osteotomy. METHODS: Between June 1986 and August 1991, we performed 172 rotational acetabular osteotomies in 168 patients with acetabular dysplasia. Of those, ninety-three hips (ninety-one patients), including twenty-three hips with pre-osteoarthritis, twenty-nine with initial osteoarthritis, and forty-one with advanced osteoarthritis, had clinical and radiographic findings available. The mean age of the patients was 32.4 years (range, twelve to forty-nine years). The duration of follow-up was a mean of twenty-three years (range, twenty to twenty-seven years) for seventy-six hips, excluding hips that underwent conversion to total hip arthroplasty. RESULTS: Conversion to total hip arthroplasty by twenty years after surgery was performed in one hip (4%) with pre-osteoarthritis, two hips (7%) with initial osteoarthritis, and fourteen hips (34%) with advanced osteoarthritis. The hips with advanced osteoarthritis had a significantly higher rate of conversion to total hip arthroplasty than hips in the other stages did (p = 0.0005). At the latest follow-up or at conversion to total hip arthroplasty, the disease stage had not progressed in seventeen hips (74%) with pre-osteoarthritis, nineteen (66%) with initial osteoarthritis, and twenty-six (63%) with advanced osteoarthritis. CONCLUSIONS: The progression of osteoarthritis after rotational acetabular osteotomy was not detected for at least twenty years in most hips with either pre-osteoarthritis or initial osteoarthritis in this cohort. Rotational acetabular osteotomy may delay conversion to total hip arthroplasty in advanced osteoarthritis. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.