Occult periprosthetic fractures of the acetabulum in THA using an elliptic cup design have no adverse impact on outcome.

Occult periprosthetic fractures have been defined as a fracture only visible on postoperative CT scans but not on postoperative plain radiography after an uneventful surgery without intraoperative fracture. The fracture rate for hemispherical and peripheral self-locking cups has been described as 8.4%. We retrospectively analyzed postoperative CT scans after primary THA to clear the question whether such occult periprosthetic fractures of the acetabulum require particular treatment strategy. Between 2014 and 2018 we identified 115 CT scans of 114 patients after primary cementless THA with elliptical cups using a direct anterior approach. The CT scans were obtained as part of other investigations. Localization of the fracture, patients demographics, clinical (WOMAC, Harris Hip Score) and radiological outcome were analyzed. Fracture and non-Fracture group were compared with regard to demographics and short-term outcome after 1 year. Four occult fractures (3.5%) were identified. Three fractures involved the posterior wall. All patients had an uneventful routine postoperative rehabilitation. Patients with occult fractures showed similar post- operative HHS and WOMAC scores at 3 (HHS p = 0.576, WOMAC p = 0.128) and 12 (HHS p = 0.479, WOMAC p = 0.588) months. There were no cup loosening nor radiolucent lines at latest follow-up (mean FU 22 months, range 12-34 months). Clinical and radiological short-term outcome was not impaired by the occurrence of an occult periprosthetic fracture of the acetabulum. The incidental detection of an occult periprosthetic fracture of the acetabulum does not seem to oblige the surgeon to adapt the postoperative regime.

[Diagnostic algorithm "FAI and sports hernia" : Results of the consensus meeting for groin pain in athletes]. / Diagnostik-Algorithmus Grenzbereich "FAI und Sportlerleiste" : Ergebnisse des Konsensustreffens Leistenschmerz beim Sportler.

As a result of the complexity and diversity of diseases in the region of the groin, differentiation of the various soft-tissue and bone pathologies remains a challenge for differential diagnosis in routine clinical practice. In the case of athletes with pain localized in the area of the groin, femoroacetabular impingement (FAI) and athlete's groin must be considered as important causes of the groin pain, whereby the common occurrence of double pathologies further complicates diagnosis. Despite the importance of groin pain and its differential diagnoses in everyday clinical practice, there has been a lack of recognized recommendations for diagnostic procedure to date. To this end, a consensus meeting was held in February 2017, in which a group composed equally of groin and hip surgeons took part. With the formulation of recommendations and the establishment of a practicable diagnostic path, colleagues that are involved in treating such patients should be sensitized to this issue and the quality of the diagnosis of groin pain improved in routine clinical practice.

Hip arthroscopy versus total hip arthroplasty in patients above 40 differences: outcome and residual complain.

This study aimed to compare patient outcomes and residual complains after hip arthroscopy (HAS) and total hip arthroplasty (THA) to improve patient counseling. It includes 140 hips/129 HAS-patients and 77 hips/62 THA-patients aged 40 to 55 years with a BMI under 30. All patients underwent primary HAS or primary THA in our hospital from 2007 until 2014. Exclusion criteria were a history of prior hip surgery or suffering sequels of childhood's hip disease, systemic inflammatory disease or avascular hip osteonecrosis. Outcome measures were WOMAC, subjective hip value, residual complains, the need of infiltrations and the complication and conversion rate. Patient data and scores were collected pre-operative, after one year and at the last follow-up. Scores indicated significant patient benefits in both groups (p < 0.0001). Variability of outcome was significantly higher and less predictable in the HAS group (HAS: 1.9 vs. THA: 0.9). While THA showed significant improvement mainly after one year, HAS showed significant improvements after one year and the latest follow-up. Residual complains were more frequent after HAS (p = 0.026). Groin pain was the main complain after HAS, limping and disturbing leg length discrepancy after THA. THA more predictably improves patient's outcome with shorter recovery time. Limping and leg length discrepancy are predominant after THA.

Validation of a Virtual Reality-Based Hip Arthroscopy Simulator.

PURPOSE: To assess construct and face validity of a novel virtual reality-based hip arthroscopy simulator using the previously validated Arthroscopic Surgery Skills Evaluation Tool (ASSET), metric parameters, and a questionnaire. METHODS: Metric parameters including task completion time, camera path, and grasper path were recorded, and the ASSET score was used to assess construct validity. Face validity was evaluated using a questionnaire. RESULTS: Nine hip arthroscopy experts, of whom the majority performed more than 200 procedures (age, 48 ± 7.3; range, 38-61 years; 8 men, 1 woman), and 33 nonexperts (age, 33 ± 7.9; range, 26-62 years; 25 men, 8 women) performed 3 individual tasks on a virtual reality-based arthroscopy simulator of a left hip. The ASSET global rating scale showed a statistically significant difference between the hip arthroscopy expert and the nonexpert group, indicating strong construct validity (25.0 in the expert group, range, 17-34, versus 15.30 in the nonexpert group, range, 8-30 [P < .001], respectively). This also applied to most metric parameters recorded by the simulator. The simulator also demonstrated high face validity. The overall impression in terms of realism was graded "completely realistic" by 17% and "close to realistic" by 62% of participants. CONCLUSIONS: The tested simulator demonstrated high construct and face validity. CLINICAL RELEVANCE: This study demonstrates the construct and face validity of a novel hip arthroscopy simulator. The device proved to be an adequate model for the simulation of some arthroscopic procedures of the hip.

Uncemented Total Hip Arthroplasty Through the Direct Anterior Approach: Analysis of a Consecutive Series of 275 Hips With a Minimum Follow-Up of 10 Years.

BACKGROUND: The purpose of this study was to document complications, outcomes, and 10-year survivorship of primary total hip arthroplasty (THA) using a direct anterior approach with an uncemented, straight, hydroxyapatite-coated stem and an uncemented cup. METHODS: A retrospective, consecutive series of 275 primary THAs through a direct anterior approach with traction table using Medacta Versafit cup and Quadra-H stem with a minimum of 10-year follow-up was identified. The cumulative 10-year survival of the implants was estimated using Kaplan-Meier estimator. All complications, reoperations, and failures were analyzed. Subjective and clinical outcomes (Subjective Hip Value, Western Ontario and McMaster Universities Osteoarthritis Index, and Harris Hip Score) were measured. RESULTS: Of 256 patients (275 hips, 143 men and 113 women) with a mean age of 63 (range, 24-85) years, 48 (19%) patients (52 hips) deceased not related to the surgery after a mean time 49 months (range, 3-118) postoperatively. At >10-year follow-up, 9 THAs were revised. The overall implant survival rate was 96.8% (95% confidence interval, 94.4-98.7) at 10 years. One cup and 1 stem were revised because of aseptic loosening. At the last follow-up, the median Subjective Hip Value was 90% (range, 20-100), the Western Ontario and McMaster Universities Osteoarthritis Index score reached a median of 0.2 points (range, 0-6.3), and the median Harris Hip Score points was 99 (range, 29-100). CONCLUSION: Primary THA through an anterior minimal invasive approach with the mentioned implants showed low revision rates and good to excellent clinical outcome after at least 10 years.

Perioperative Fractures in Cementless Total Hip Arthroplasty Using the Direct Anterior Minimally Invasive Approach: Reduced Risk With Short Stems.

BACKGROUND: The direct minimally invasive anterior approach (DMIAA) and the use of uncemented stems demonstrated an increase in intraoperative fractures in recent literature. Whether the different design of the stems additionally influences the incidence of perioperative local complications, was the goal of this study. METHODS: From January 2008 until June 2010, all patients undergoing primary cementless total hip arthroplasty, using a DMIAA, were consecutively included. The choice of the implant was defined by the day of operation. Age, gender, body mass index, type of prosthesis, and the practical experience of the performing surgeon were retrospectively analyzed. Of main interest were intraoperative fractures, postoperative hematoma, and wound healing. RESULTS: Six hundred forty consecutive patients (64 years [18-94], 339 female, 53%, body mass index 26) have been included. A Quadra-H stem (Medacta) was used in 457 patients (71%). In 183 (29%) patients, a short stem designed for the DMIAA (130 Fitmore, Zimmer and 53 AMIStem, Medacta) was used. We counted 34 (5.3%) intraoperative fractures (16 at the greater trochanter, 18 proximal shaft fractures), 20 (4%) hematomas, and 8 (2%) wound healing problems. The standard length stem showed more local complications (11.8% vs 4.4%) (P = .014, odds ratio 1.63, confidence interval 1.1-2.4) and significantly more (6.8% vs 1.6%) intraoperative fractures (P = .027, odds ratio 1.98, confidence interval 1.1-3.6). CONCLUSION: The standard length stem showed more perioperative complications, especially periprosthetic fractures. It seems that these implants not only put more stress to proximal osseous structures, but there might also be more traction and irritation to the soft tissue while preparing, resulting in more hematomas and wound healing problems.

Arthroscopic Hip Surgery: Frequency of Postoperative MR Arthrographic Findings in Asymptomatic and Symptomatic Patients.

Purpose To determine and compare the frequency of imaging abnormalities in asymptomatic and symptomatic patients after arthroscopic hip surgery. Materials and Methods This study was approved by the institutional review board. Informed consent was obtained from all patients. Thirty-four patients (17 asymptomatic and 17 symptomatic patients) underwent 1.5-T magnetic resonance (MR) arthrography of the hip 1 year after arthroscopic treatment of femoroacetabular impingement. Two readers independently analyzed all MR arthrographic images for the presence of abnormal imaging findings, including capsular adhesions at the femoral neck, obliteration of the paralabral sulcus, labral defects, and defects of the hip capsule in several anatomic positions (anterior to posterior). Postoperative findings were compared with linear and generalized linear mixed-effects regression models. Results Capsular adhesions at the anterior femoral neck were present in 12 of the 34 patients (35%), and there were no differences between the groups or readers (P = .99). The paralabral sulcus was obliterated in at least one anatomic location in 94% (reader 1, 32 of 34 patients) and 100% (reader 2, 34 of 34 patients) of patients (P = .99). Residual labral tears were detected in 35% of asymptomatic patients (six of 17 patients) and 41% of symptomatic patients (seven of 17 patients) by reader 1 and in 53% of asymptomatic and symptomatic patients (nine of 17 patients in each group) by reader 2, without significant differences between the groups (P = .81). Defects of the hip capsule were more common in asymptomatic patients (77% [13 of 17 patients] for reader 1 and 53% [nine of 17 patients] for reader 2) than in symptomatic patients (59% [10 of 17 patients] for reader 1 and 47% [eight of 17 patients] for reader 2), but without significant differences (P = .33). Conclusion Obliteration of the paralabral sulcus was the most frequent finding after arthroscopic hip surgery in both asymptomatic and symptomatic patients, and capsular adhesions at the anterior femoral neck were present in 35% of patients in both groups. © RSNA, 2016.

MR imaging of soft tissue alterations after total hip arthroplasty: comparison of classic surgical approaches.

OBJECTIVES: To compare soft-tissue changes after total hip arthroplasty with posterior, direct-lateral, anterolateral, or anterior surgical approaches. METHODS: MRI of 120 patients after primary total hip arthroplasty (30 per approach) were included. Each MRI was assessed by two readers regarding identification of surgical access, fatty muscle atrophy (Goutallier classification), tendon quality (0 = normal, 1 = tendinopathy, 2 = partial tear, 3 = avulsion), and fluid collections. Readers were blinded to the surgical approach. RESULTS: Surgical access was correctly identified in all cases. The direct lateral approach showed highest Goutallier grades and tendon damage for gluteus minimus muscle (2.07-2.67 and 2.00-2.77; p = 0.017 and p = 0.001 for readers 1 and 2, respectively) and tendon (2.30/1.67; p < 0.0005 for reader 1/2), and the lateral portion of the gluteus medius tendon (2.77/2.20; p < 0.0005 for reader 1/2). The posterior approach showed highest Goutallier grades and tendon damage for external rotator muscles (1.97-2.67 and 1.57-2.40; p < 0.0005-0.006 for reader 1/2) and tendons (1.41-2.45 and 1.93-2.76; p < 0.0005 for reader 1/2). The anterolateral and anterior approach showed less soft tissue damage. Fluid collections showed no differences between the approaches. CONCLUSIONS: MRI is well suited to identify surgical approaches after THA. The anterior and anterolateral approach showed less soft tissue damage compared to the posterior and direct lateral approach. KEY POINTS: • Identification of the surgical approach is well possible with MR imaging. • Anterolateral/anterior approaches show less soft-tissue damage compared to lateral/posterior approaches. • Posterior approaches show marked damage to external rotator tendons and muscles. • After direct lateral approaches the gluteus minimus tendon/muscle show severe damage.

MR findings associated with positive distraction of the hip joint achieved by axial traction.

PURPOSE: To determine which MR-arthrography findings are associated with positive hip joint distraction. MATERIALS AND METHODS: One hundred patients with MR arthrography of the hip using axial traction were included. Traction was applied during the MR examination with an 8 kg (females) or 10 kg (males) water bag, attached to the ankle over a deflection pulley. Fifty patients showing joint space distraction were compared to an age- and gender-matched control group of 50 patients that did not show a joint distraction under axial traction. Two radiologists assessed the neck-shaft angle, lateral and anterior center-edge (CE) angles, CE angles in the transverse plane, extrusion index of the femoral head, acetabular depth, alpha angle, acetabular version, ligamentum teres, joint capsule and ligaments, iliopsoas tendon and the labrum. RESULTS: Mean joint space distraction in the study group was 0.9 ± 0.6 mm. Patients with positive joint space distraction had significantly higher neck-shaft angles (control group 131.6 ± 5.4°/study group 134.1 ± 6.1°, p < 0.05), smaller lateral CE angles (38.1 ± 5.9°/34.6 ± 7.2°, p < 0.05), smaller overall transverse CE angles (161.4 ± 9.9°/153.6 ± 9.6°, p < 0.001), smaller acetabular depth (4.1 ± 2.4 mm/5.8 ± 2.5 mm, p < 0.01), higher alpha angles (53.5 ± 7.8°/59.2 ± 10.1°, p < 0.01) and a thicker ligamentum teres (4.7 ± 1.4 mm/5.4 ± 1.8 mm, p < 0.05). The other parameters revealed no significant differences. ICC values for interobserver agreement were 0.71-0.95 and kappa values 0.43-0.92. CONCLUSION: Increased neck-shaft angles, small CE angles, small acetabular depth, higher alpha angles and a thick ligamentum teres are associated with positive joint distraction.

Minimum five-year wear rate of metal-on-highly cross-linked polyethylene in primary total hip arthroplasty.

PURPOSE: Highly cross-linked polyethylenes (PE) have been developed with encouraging results in terms of wear. Another body of the literature has indicated potential catastrophic failures related to reduced fatigue properties and oxidation. Each PE available on the market has its own processing characteristics. The aim of this retrospective study was to evaluate the minimum five-year wear properties of an original highly cross-linked PE in a consecutive series of primary THAs. METHODS: Between August 2005 and December 2007, 80 patients with a mean age of 62.7 years were included. All patients had a 28-mm CoCr femoral head articulating with a highly cross-linked insert (Highcross®, Medacta SA) that was 100 Mrads gamma radiated, remelted at 150 °C, and ethylene oxide sterilized. The primary criterion for evaluation was the femoral head penetration, as measured by Hip Analysis Suite software. The steady state wear was also calculated. Functional results were evaluated according to the WOMAC score. RESULTS: Complete data were available for analysis in 67 patients at a mean follow-up of 5.5 years. The mean femoral head penetration was 0.128 ± 0.62 mm and the steady state wear was-0.025 ± 0.22 mm/year. The WOMAC score significantly decreased from 16.5 ± 5.93 pre-operatively to 4.12 ± 5.5 at the latest follow-up (p <0.001). CONCLUSIONS: The minimal five-year results of this retrospective study indicate that this particular highly cross-linked and remelted polyethylene had a low wear rate. Longer-term results are needed to warrant that these mid-term data will generate less osteolysis and resultant aseptic loosening.

Double mobility cup total hip arthroplasty in patients at high risk for dislocation: a single-center analysis.

INTRODUCTION: Double mobility cup systems (DMCS) have gained increasing acceptance, especially in patients at high risk for dislocation. The aim of this investigation was to analyze the frequency and indications of the DMCS use in our praxis and to evaluate dislocation and cup revision rates after a minimum follow-up of 2 years. MATERIALS AND METHODS: All patients implanted with a DMCS from May 2008 to August 2011 were identified from our institutional database of primary and revision THA procedures. Patient demographics, including ASA score, were recorded, along with details of the surgical procedures, indications for DMCS use, and post-operative clinical course and any complications. Radiographs were analyzed for implant positioning and radiological signs of loosening. RESULTS: 1046 primary THA were implanted, of these 39 (4 %) primary DMCS. Indications were severe neuromuscular disease (SND) (14), hip abductor degeneration (HAD) (9), cognitive dysfunction (CD) (8) and others. 345 revision THA were performed, of these 50 (14 %) revision DMCS. Indications were recurrent dislocations (27), multiple prior hip surgeries (13), HAD (5), CD (3) and others. Overall dislocation rate was 2/89 (2 %); both in revision THA. Overall cup revision rate was 5/89 (6 %): 3 septic, 1 periprosthetic acetabular fracture, 1 "intraprosthetic dissociation". 67 patients were available for the standardized questionnaire at a median follow-up of 43 months (range 25-78). 19 patients were not available for two-year follow-up: 17 died and two were lost to follow-up. CONCLUSIONS: This study supports the use of DMCS constructs in primary and revision hip arthroplasty for specific high-risk patients. We continue to indicate DMCS in this patient group. We do caution against extending indications for DMCS to lower risk patient groups due to unknown issues surrounding wear and component longevity.

Hip MRI: how useful is intraarticular contrast material for evaluating surgically proven lesions of the labrum and articular cartilage?

OBJECTIVE: The objective of our study was to prospectively compare the diagnostic performance of MR arthrography and conventional MRI with surgical correlation in the same patient for detecting labrum and articular cartilage defects. SUBJECTS AND METHODS: Twenty-eight patients (mean age, 31.8 years) underwent MR arthrography, conventional MRI, and subsequent hip surgery, which served as the reference standard. Labrum and cartilage defects were evaluated at MRI by two independent readers. A McNemar test and kappa statistics were used for statistical analysis. RESULTS: At surgery, 31 labral tears were identified. MR arthrography had an advantage over conventional MRI for detecting labral tears at the anterosuperior quadrant (sensitivity of MR arthrography, 81% and 69% for readers 1 and 2, respectively; sensitivity of conventional MRI, 50% for both readers); this difference in performance between MR arthrography and conventional MRI was statistically significant for reader 1 (p = 0.02) but not for reader 2 (p = 0.2). Interobserver agreement for labral tears was higher for MR arthrography (κ = 0.81) than for conventional MRI (κ = 0.63). Surgery showed 31 acetabular cartilage defects and nine femoral cartilage defects. MR arthrography had an advantage over conventional MRI for detecting acetabular cartilage defects (sensitivity of MR arthrography, 71% and 92% for readers 1 and 2, respectively; sensitivity of conventional MRI, 58% and 83%), whereas there was no advantage to using MR arthrography for detecting femoral cartilage defects with statistically significant difference for the acetabular cartilage or femoral cartilage. Interobserver agreement was slightly higher for MR arthrography (κ = 0.50) than for conventional MRI (κ = 0.40) for assessing the acetabular cartilage and was almost identical for the femoral cartilage (κ = 0.62 and 0.63, respectively). CONCLUSION: MR arthrography was superior to conventional MRI for detecting labral tears and acetabular cartilage defects and showed a higher interobserver agreement. For femoral cartilage lesions, both modalities yielded comparable results.

Femoral neck fractures after arthroscopic femoral neck osteochondroplasty for femoroacetabular impingement.

PURPOSE: The objective of this study was to evaluate the rate, associated risk factors and outcome of insufficiency femoral neck fractures following arthroscopic femoral neck osteochondroplasty for femoroacetabular impingement. METHODS: Between 2005 and 2009, a consecutive series of 376 arthroscopic femoral osteochondroplasties for femoroacetabular impingement were performed and analysed. Seven postoperative fractures were found and comprise the fracture group. The amount of femoral head-neck bone resected as assessed on follow-up cross table lateral views, as well as age, gender, height, weight and BMI, was compared between the fracture group and the entire collective. Subjective outcome was recorded using the WOMAC score. RESULTS: Seven fractures (1.9 %) were identified. All occurred in males at an average of 4.4 weeks postoperatively and were considered insufficiency fractures. The fracture group had a significantly higher mean age (p = 0.01) and height (p = 0.013). Within the fracture group, alpha angles were lower (p = 0.009) and resection depth ratios were higher (p < 0.001). The femoral offset was significantly higher (p = 0.016) in the fracture group and in male patients (p < 0.001). The cut-off value for resection depth ratio on cross table lateral radiograph was 18 % of the femoral head radius. After a mean follow-up of 20 months, an inferior WOMAC (p = 0.030) was recorded in the fracture group. CONCLUSION: Femoral neck insufficiency fractures were identified in 1.9 % of our arthroscopic femoral osteochondroplasty cases. Significant new pain following a period of satisfactory recovery after arthroscopic femoral neck osteochondroplasty should alert the surgeon to the possibility of this complication. If a resection depth ratio of more than 18 % is recognized on the postoperative cross table lateral view, particularly in male patients with a high femoral head-shaft offset, the risk of postoperative insufficiency fracture is increased. This study not only defines the complication rate, but also identifies associated risk factors and determines the influence on the postoperative subjective short-term result. Important information for both the patient and orthopaedic surgeon is provided and may have a direct consequence on the postoperative protocol.

Postoperative imaging in femoroacetabular impingement.

Femoroacetabular impingement (FAI) has been recognized as a common cause of pain, limited range of motion, and development of early osteoarthritis of the hip in adolescents and adults. Current surgical approaches include femoral osteochondroplasty, acetabular rim resection, and reattachment of torn labrum as either open surgical or arthroscopic techniques as well as periacetabular osteotomy. Conventional radiographs are routinely obtained in the postoperative setting. In addition, MRI serves for work-up in patients with persistent or recurrent groin pain after surgery. Inappropriate correction of the underlying femoral or acetabular osseous abnormality, insufficiency fractures of the femoral neck due to bone resection, intra-articular adhesions, ongoing joint degeneration including advanced cartilage damage, iatrogenic cartilage injury, retear of the labrum, rarely avascular necrosis of the femoral head, defects of the hip joint capsule, or heterotopic ossification might be observed after surgery for FAI.

Early serum procalcitonin level after primary total hip replacement.

BACKGROUND: Procalcitonin (PCT) is a useful surrogate marker for the differentiation of postoperative infection and unspecific inflammatory reaction after surgery. It is known that postoperative course of the PCT serum level varies with type of surgery. No data exists about the postoperative course of serum PCT levels after primary total hip replacement (THR). PURPOSE: To characterize early postoperative serum PCT levels in uneventful primary THR compared to postoperative levels of different frequently used inflammatory blood parameters. METHOD: We prospectively investigated 31 patients. Blood samples were taken preoperatively and for 5 days postoperatively. PCT levels were compared with C-reactive protein (CRP), interleukin-6 (IL-6), and blood leucocyte counts (WBC). RESULTS: In uneventful THR PCT levels showed a uniform low-level course with a peak at the second postoperative day. At the fifth day values returned to almost preoperative levels. On contrary, CRP levels remained high during the entire observational period. Only IL-6 levels showed a peak at postoperative day one with a quick and uniform return to preoperative levels. CONCLUSION: Similar to observations in cardiothoracic, intestinal, and neural surgeries, postoperative course of PCT after primary THR showed a uniform low-level course with a peak at the second postoperative day but below expected levels in systemic infections.

Outcome after proximal femoral fractures during primary total hip replacement by the direct anterior approach.

BACKGROUND: The literature suggests that intraoperative fractures of the greater trochanter and the metaphysis are increased with uncemented stems and the direct anterior approach. This study aims to determine the incidence and assess the functional and radiological outcome after such fractures. METHODS: 484 consecutive total hip replacements (THR) (64 ± 12 years) were analyzed. We treated trochanteric fractures conservatively without any further denuding, and secured metaphyseal fissures with cerclages. Postoperative X-rays and at the latest follow-up were compared to assess secondary fracture displacement and stem subsidence. Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores after 1 year were analyzed. For each patient sustaining a fracture, two patients without fractures were matched in terms of age, body mass index and gender. RESULTS: 13 (2.7 %, 5 male, 68 ± 9 years) patients with intraoperative fractures of the greater trochanter (n = 8) or the metaphysis (n = 5) were analyzed. Consolidation was observed in 7/8 patients sustaining a trochanteric fracture while secondary displacement of the fragment occurred in one case. Stem subsidence was observed in 2/5 cases (5 and 7 mm). Patients who sustained a fracture showed a trend towards poorer WOMAC scores at 1 year postoperatively, compared to patients without fractures. A significantly increased joint stiffness was also observed. CONCLUSION: The intraoperative fracture risk in this series of THR through a direct anterior approach was 2.7 %. Trochanteric fractures do heal without primary fixation. Metaphyseal fractures heal well if immediately stabilized with a cerclage.

Surgical hip dislocation versus hip arthroscopy for femoroacetabular impingement: clinical and morphological short-term results.

INTRODUCTION: Surgical hip dislocation (SHD) is an accepted standard to treat femoroacetabular impingement (FAI). However, arthroscopic techniques have gained widespread popularity and comparable results are reported. The purpose of this prospective comparative study was to test the hypothesis that, when compared to SHD, hip arthroscopy (HA) results in faster recovery, better short-term outcome, and equivalent morphological corrections. MATERIALS AND METHODS: 38 patients presenting with clinically and morphologically verified isolated FAI were allocated to either HA or SHD. Morphological evaluation consisted of pre- and postoperative X-rays, and arthro-MRI. Demographic data, sport activities, hospital stay, complications, and the time off work were recorded. The subjective hip value, WOMAC, HHS, and hip abductor strength were measured up to 1 year. RESULTS: Shorter hospital stay and time off work, less pain at 3 months and 1 year, higher subjective hip values at 6 weeks and 3 months, and better WOMAC at 3 months were seen after HA. The HHS and the hip abductor strengths were higher in the HA group. However, morphological corrections at the head-neck-junction achieved by HA showed some overcorrection when compared to SHD. Labral refixation was performed less frequent in the HA group. CONCLUSION: When compared to SHD, HA results in faster recovery and better short-term outcome. However, some overcorrection of the cam deformity and limited frequency of labrum refixation with HA in this study may have a negative impact on long-term outcome.

Supraacetabular fossa (pseudodefect of acetabular cartilage): frequency at MR arthrography and comparison of findings at MR arthrography and arthroscopy.

PURPOSE: To evaluate the frequency of the supraacetabular fossa (SAF) (pseudodefect of acetabular cartilage) at magnetic resonance (MR) arthrography of the hip and to compare the MR findings with those from arthroscopy. MATERIALS AND METHODS: All patients gave written permission for anonymized use of their medical data for scientific purposes before the imaging examination. The study was submitted to the institutional review board, and the need to obtain additional approval was waived. A medical student, a radiology fellow, and two senior radiologists reviewed 1002 consecutive MR arthrograms for the presence of an accessory bony fossa in the roof of the acetabulum, or SAF. SAF was classified into two types: type 1, which was filled with contrast material on MR arthrograms, and type 2, which was filled with cartilage. The width of the SAF was measured on coronal and sagittal MR images. MR arthrograms showing SAF were evaluated for subchondral reactions. Findings at MR arthrography were compared with those from arthroscopy in four hip joints with SAF type 1 and 13 with SAF type 2. RESULTS: Sixteen of the 1002 hip joints (1.6%; four female and 12 male patients; mean age, 20.1 years) had SAF type 1 (mean width, 5.2 × 4.5 mm). Eighty-nine hip joints (8.9%; 43 female and 46 male patients; mean age, 37.8 years) had SAF type 2 (mean width, 5.1 × 4.7 mm). No subchondral changes were found around the SAF. No cartilage defect was seen at the site of the SAF at arthroscopy. CONCLUSION: The high frequency of SAF on MR arthrograms (10.5%), the absence of subchondral reaction, and the absence of cartilage defects at arthroscopy indicate that the SAF of the acetabulum likely represents a variant.

Continuous epicapsular ropivacaine 0.3% infusion after minimally invasive hip arthroplasty: a prospective, randomized, double-blinded, placebo-controlled study comparing continuous wound infusion with morphine patient-controlled analgesia.

BACKGROUND: In this study, we investigated the impact of a continuous wound infusion with ropivacaine 0.3% on pain and morphine consumption after minimally invasive hip arthroplasty. METHODS: Seventy-six consecutive patients scheduled for elective minimally invasive hip replacement using spinal anesthesia were prospectively included in this double-blind study. Epicapsular placement of a 15-cm fenestrated catheter was performed by the surgeon. Patients were randomized to receive either 20 mL ropivacaine 0.3% (R-group) or 20 mL NaCl 0.9% (P-group) applied into the wound as a bolus before wound closure. A continuous infusion of either ropivacaine 0.3% or placebo was then infused at 8 mL/h for 48 hours after surgery with an elastomeric pump. Morphine IV-patient-controlled analgesia was offered to all patients. Morphine consumption, pain at rest and with motion, and total and unbound ropivacaine plasma concentration were recorded during the 48-hour study period. Postoperative follow-up was performed at 3 months. RESULTS: Demographic and surgical data were similar in both groups. Mean morphine consumption was significantly lower in the R-group than in the P-group during the first 48 postoperative hours: 45.4 ± 9.5 vs 69.7 ± 9.6 (P < 0.0001). There was a mean reduction of 14.4 mg for the first 24 postoperative hours (95% confidence interval [CI] 12.6 to 16.1) and 20.8 mg for the next 24 hours (95% CI 19.1 to 22.4). Pain scores at rest and with motion were lower in the R-group (P < 0.0001). Mean patient satisfaction increased 22.7% from baseline (CI 95% 15.9 to 29.6) in the R-group. Total and unbound ropivacaine plasma concentrations were below toxic levels in the R-group. The free ropivacaine concentration was 0.14 and 0.11 µgmol/L at T(24) and T(48), respectively, in the R-group. At 3 months postoperatively, hip pain and analgesic consumption were similar, but a significant reduction in wound discomfort to touch (31.2; 95% CI 27.7 to 34.7) and pressure (24; 95% CI 20.1 to 27.9) was observed in the R-group (P < 0.0001). CONCLUSIONS: Continuous epicapsular wound infusion with ropivacaine 0.3% after minimally invasive hip replacement is an efficient technique for reducing morphine consumption and improving the quality of postoperative analgesia. The beneficial effects of this technique are still present 3 months after surgery.

Trochanteric osteotomy in primary and revision total hip arthroplasty: risk factors for non-union.

BACKGROUND: Trochanteric osteotomies (TO) facilitate exposure and "true hip reconstruction" in complex primary and revision total hip arthroplasty (THA). However, non-union represents a clinically relevant complication. The purpose of the present study was to identify risk factors for trochanteric non-union. METHODS: All cases of THA approached by TO during the past 10 years were analyzed with respect to potential risk factors for non-union. RESULTS: In 298 cases complete data were available for analysis. Trochanteric union occurred in 80.5%, fibrous union in 5.4% and non-union 14.1%. Risk factor analysis revealed a four times higher risk for non-union in anterior trochanteric slide osteotomies compared to extended trochanteric osteotomies and a three times higher risk in cemented versus non-cemented stems. Multiple logistic regression analysis revealed patient's age and use of cement to be independent risk factors for non-union. CONCLUSIONS: Femoral cementation and increasing age negatively influence the union of trochanteric osteotomies.