Comparative Study for Postoperative Initial Fixation Patterns of Two Different Types of Cementless Short Stem Using Three-Dimensional Templating Software.

Background: While cementless short stems have become popular in total hip arthroplasty (THA), Metha is a relatively recent development that differs from other short stems in its initial fixation concept of partial collum-sparing metaphyseal anchorage. The purpose of this study was to quantify the contact state between Metha and the femur. Additionally, we investigated the difference in contact points between Meta and Fitmore, which is one of the more popular curved short stems. Methods: We conducted a retrospective review of 42 hips that underwent THA using Metha and 41 hips using Fitmore. Stem-to-femur contact was evaluated by density mapping using a three-dimensional digital template system to quantify the contact condition according to the modified Gruen zone. The criterion for the stem-to-bone contact boundary was defined as a computed tomography value of 543 Hounsfield. Results: Quantitative evaluation of Metha according to the modified Gruen zones showed the ratio of surface area with high cortical contact in each zone. The results were 4.6% ± 5.7% in zone 1, 0.9% ± 2.3% in zone 2, 19.1% ± 12.9% in zone 3, 1.4% ± 3.2% in zone 5, 29.6% ± 16.4% in zone 6, and 25.1% ± 17.7% in zones 7. Evaluation of Fitmore for the same zones was as follows: 1.6% ± 2.4%, 18.5% ± 16.9%, 20.8% ± 17.4%, 12.7% ± 12.8%, 3.7% ± 5.8%, and 13.3% ± 10.3%. Comparing the two groups, the contact area was significantly greater for Metha in zones 1, 6 and 7 and Fitmore in zones 2 and 5 (p < 0.05). Conclusions: It is possible for Metha to achieve metaphyseal anchoring by contacting the cortical bone at the proximal femur, thus avoiding proximal offloading. To the best of our knowledge, no previous studies have quantitatively reported stem-to-cortical bone contact conditions in curved short stems.

Total Hip Arthroplasty Concomitant with Patellofemoral Arthroplasty and Medial Patellofemoral Ligament Reconstruction for a Patient with Patellar Dislocation Combined with Hip Dysplasia: A Case Report of a Successful Outcome at 5-Year Follow-Up.

BACKGROUND: Posttraumatic patellar dislocation is rare, and consistent surgical strategy therefore has not been defined due to multifactorial factor. In this case study, we treated a case of a patellar dislocation with hip osteoarthritis and increased femoral anteversion by performing a two-staged surgery. In the first stage, total hip arthroplasty was performed, and in the second stage, simultaneous patellofemoral arthroplasty and medial patellofemoral ligament reconstruction using semitendinosus tendon autograft were performed. Case Report. A 56-year-old female patient who previously had right hip osteoarthritis complained of right knee pain after a fall. Radiographic examination showed lateral dislocation of the patella with osteoarthritic (OA) change in the patellofemoral joint and an excessive femoral anteversion with OA change on the right hip joint. Total hip arthroplasty was performed firstly to decrease femoral anteversion. Then, simultaneous patellofemoral arthroplasty and medial patellofemoral ligament reconstruction was performed for residual patellar dislocation and patellofemoral OA without tibiofemoral joint OA. At the time of the 5-year follow-up after surgery, the patient was able to walk with a wheelbarrow without any complications. CONCLUSION: To the best of our knowledge, this is the first case of a patellar dislocation with an increased femoral anteversion and patellofemoral OA treated by a combination of total hip arthroplasty, patellofemoral arthroplasty, and medial patellofemoral ligament reconstruction. The clinical outcome improved at 5 years after these surgeries. Therefore, these surgical options can be considered to be useful.

Radiological Evaluation of the Relationship Between Cortical Hypertrophy and Stress Shielding After Total Hip Arthroplasty Using a Cementless Stem.

BACKGROUND: Unloading of the proximal medial femoral cortex is usually associated with an increased bone strain at the distal part of the prosthesis, which may cause distal femoral cortical hypertrophy (CH). The objective of this study was to determine the factors that may be considered a predisposition to distal femoral CH and its effect on the stress shielding (SS) or durability of the fixation of the stem. METHODS: A total of 240 total hip arthroplasties were performed between January 2006 and December 2016, with all hips implanted with a Bicontact stem. The minimum follow-up period was more than 2 years, and the mean follow-up period was 7.2 years. The radiographic outcome was assessed on an anteroposterior hip radiograph. CH and SS were assessed on postoperative radiographs in the Gruen zone. We defined CH that appeared in zone 3 or 5 as 'the focal type' and defined CH that appeared in zones 2, 3, 4, 5, and 6 as 'the diffuse type.' SS followed the procedures from the Engh classification. RESULTS: CH was found in 72 hips (30% of the 240 hips), the focal type was found in 23 hips (9.6% of the 240 hips), and the diffuse type was found in 49 hips (20.4% of the 240 hips). SS was found in 41 hips (17.1% of 240 hips), including 32 hips with SS, which was found after the development of CH. One hip was from the focal-type CH and 31 hips were from the diffuse-type CH. SS, which is typically found in Engh classification types 1 and 2 developed in 13 hips, and SS, which is widely seen in Engh classification types 3 and 4 developed in 19 hips. All 19 hips with progressed SS were found after the diffuse-type CH had developed. In addition, among the 19 hips with progressed SS, Dorr type A was found in 0 hips, Dorr type B in 8 hips, and Dorr type C in 11 hips. CONCLUSIONS: According to the results of our radiological evaluation, development of the diffuse-type CH after total hip arthroplasty using Bicontact stems is one of the critical causes of the later development of SS and could be predicted to progress to SS. To prevent the development of the diffuse-type CH, the indication to choose a Bicontact stem for a Dorr type C with osteoporotic bone should be considered.

New combined anteversion technique in hybrid THA: cup-first procedure with CT-based navigation.

PURPOSE: Combined anteversion (CA) technique (stem-first procedure) is generally accepted as the optimal technique to attain an appropriate CA value in total hip arthroplasty (THA). However, cup anteversion is strongly influenced by the native femoral anteversion. Accordingly, anterior protrusion of the cup in the acetabulum might occur. The purpose of the present study is to investigate the achievement of the optimal CA while avoiding anterior cup protrusion and examine the significance of our new CA technique with cup-first procedure in hybrid THA. METHODS: Seventy-nine hybrid THAs with the cup-first procedure used a CT-based navigation system for cup positioning. In the preoperative planning, cup anteversion was aimed at approximately 20°. However, in actuality, sufficient cup coverage in the original acetabulum based on individual anatomy is given priority over cup placement based on CT-based planning to ensure adequate cup coverage. The target stem anteversion was determined following Widmer's mathematical formula (37.3 = femoral stem anteversion × 0.7 + cup anteversion). Cemented stem was inserted according to the target stem anteversion angle. RESULTS: Regarding the assessment of overall alignment, the calculated Widmer's CA values during surgery and postoperative CT evaluation were 34.1° ± 6.0° (range 20.7°-51.2°) and 35.1° ± 6.7° (range 21.6°-50.7°). There were 72 hips (91.1%) within 25°-50° of CA. Cup protrusion length averaged 2.0 mm ± 2.6 mm (0-8.8 mm) in the axial view and 0.4 mm ± 1.0 mm (0-3.6 mm) in the sagittal view. Cup protrusion length of more than 5 mm was indicated in 10 hips, and no hips observed more than 10 mm. CONCLUSION: Our new CA technique (cup-first procedure) with hybrid THA was able to achieve optimal CA value while avoiding anterior cup protrusion.

Acetabular reconstruction for primary and revision total hip arthroplasty using Kerboull-type acetabular reinforcement devices-case-control study with factors related to poor outcomes of surgery.

Kerboull-type acetabular support rings (KT) and allogenic bone graft were used for severe periacetabular bone loss with primary and revision total hip arthroplasty (THA). The purpose of this case-control study is to evaluate the risk factors related to poor outcomes of surgery.Sixty patients underwent primary THA and revision THA using allogenic bone graft with KT for large acetabular deficiency. These patients were retrospectively evaluated postoperatively and followed-up by radiograph. The minimum follow-up period was 4 years and averaged 7 years. A radiological failure was defined by the following criteria:Expected risk factors were defined as female, age >75 years, body mass index (BMI) >25%, medical history of hypertension, renal failure, liver steatosis, diabetes, hyperlipidemia, cardiac infarction, smoking, American Academy of Orthopedic Surgery (AAOS) classification III or IV, bleeding>500 mL, time of surgery >3hours, high hip center-type KT, inclination of KT >45 degrees, screw angle >25 degrees, morselized bone graft, Kawanabe's classification stage 3 or 4 and revision surgery. Nineteen hips (31.6%) revealed radiological failure according to our criteria, and revision THA was performed in 2 hips (3.3%). In the statistical analysis, morselized bone graft and high hip center-type KT were identified as factors of poor outcomes of surgery.

Total hip arthroplasty using stem-first technique with navigation: the potential of achievement of the optimal combined anteversion being a risk factor for anterior cup protrusion.

PURPOSE: In the combined anteversion (CA) technique for total hip arthroplasty (THA) with a cementless stem, cup anteversion is strongly influenced by the native femoral anteversion. It is hypothesized that in cases with large native femoral anteversion, cup anteversion can be decreased, and anterior cup protrusion from the anterior edge of the acetabulum could occur due to the achievement of optimal CA. In this study, the accuracy of CA in THA with the CA technique using imageless navigation and the relationship between the protrusion of the anterior edge of cup and optimum CA was retrospectively evaluated. METHODS: Ninety-seven patients (104 hips) who underwent primary THA by the CA technique using image-free navigation were enrolled in the study. The femoral stem was placed following the individual femoral anteversion so that the target cup anteversion could be determined following a mathematical formula (37 = femoral stem anteversion × 0.7 + cup anteversion). Results The resulting CA values effectively achieved accurate CA with 39.49 ± 5.03° postoperatively. On the other hand, anterior cup protrusion was measured by computed tomography image. A cup protrusion length of more than 3 mm was indicated for 60 cases (57.7%). All included patients were divided into two groups: Group 1 as protrusion positive and Group 2 as protrusion negative. In Group 1, preoperative femoral anteversion and postoperative stem anteversion were significantly higher, while postoperative cup anteversion was significantly lower. However, the postoperative CA value indicated no significant difference between the groups. CONCLUSIONS: The CA (stem-first) technique with image-free navigated THA could effectively achieve accurate CA. On the other hand, a large number of cases revealed anterior cup protrusion due to the low cup anteversion.

Total Hip Arthroplasty for Femoral Neck Fracture after Postoperative Intertrochanteric Fracture in a Patient with Spontaneous Fused Hip.

A 64-year-old woman with a spontaneous fused hip sustained a left femoral neck fracture. It was revealed that her left hip joint had a long-standing spontaneous hip fusion due to end-stage osteoarthritis. Additionally, she sustained an ipsilateral femoral intertrochanteric fracture and underwent osteosynthesis using a dynamic hip screw 8 years ago. The one-stage THA was successfully treated with no major complications and good functional recovery was obtained. The hip range of motion improved remarkably at one year after surgery. The Modified Harris Hip Score improved from an estimated 70 points before fracture to 95 points at final follow-up.

Curved periacetabular osteotomy using intraoperative real-time 3-dimensional computed tomography with a robotic C-arm system: A case report.

RATIONALE: Curved periacetabular osteotomy (CPO) is a procedure with excellent surgical outcome that has been proposed for patients with development dysplasia of the hip (DDH). However, the surgical outcomes depend on the surgeon's experience and proficiency. PATIENT CONCERNS: A 38-year-old female indicated she was experiencing left hip pain while walking. DIAGNOSES: The patient was diagnosed with early-stage hip osteoarthritis due to DDH. INTERVENTIONS: The patient underwent CPO while a 3-dimensional flat-panel C-arm (Artis zeego; Sciemens Healthcare, Forchheim, Germany) was used to confirm the real-time 3-dimensional computed tomography (CT) images during surgery. It was possible to confirm the accurate osteotomy curve using CT images twice during surgery: at the time of the ischial osteotomy and the quadrilateral surface osteotomy. OUTCOMES: An ideal C-shaped osteotomy line was created as shown on the postoperative CT images. In addition, neither posterior column fracture nor intra-articular osteotomy was confirmed. LESSONS: The CPO using Artis zeego resulted is a satisfactory outcome, and this is the 1st report in the world to discuss the benefits of Artis zeego in pelvic osteotomy.

Comparison of Continuous Femoral Nerve Block with and Without Combined Sciatic Nerve Block after Total Hip Arthroplasty: A Prospective Randomized Study.

In association with the growing interests in pain management, several modalities to control postoperative pain have been proposed and examined for the efficacy in the recent studies. Various modes of peripheral nerve block have been proposed and the effectiveness and safety have been examined for each of those techniques. We have described our clinical experiences, showing that continuous femoral nerve block could provide a satisfactory analgesic effect after total hip arthroplasty (THA) procedure. In this study, we compared the effectiveness and safety of continuous femoral nerve block with and without sciatic nerve blockade on pain control after THA. Forty patients scheduled for THA were included in the study and randomly divided into 2 groups. Postoperative analgesic measure was continuous femoral nerve block alone, while the identical regimen of continuous femoral nerve block was combined with sciatic nerve block. The amount of postoperative pain was evaluated in the immediate postoperative period, 6 hours, and 12 hours after surgery. Moreover, postoperative complications as well as requirement of supplemental analgesics during the initial 12 hours after surgery were reviewed in the patient record. The obtained study results showed that the supplemental sciatic nerve blockade provided no significant effect on arrival at the postoperative recovery room, while the NRS pain score was significantly reduced by the combined application of sciatic nerve blockade at 6 and 12 hours after surgery. In the investigation of postoperative analgesiarelated complications, no major complication was encountered without significant difference in complication rate between the groups.

Treatment strategy for amyloid hip arthropathy in long-term hemodialysis patients.

BACKGROUND: The number of hemodialysis patients has been progressively increasing in our country. On the other hand, chronic hip arthropathy associated with long-term hemodialysis is a devastating problems affecting patients' quality of life. In our previous study, we proposed a classification system for radiological abnormalities seen in hemodialysis-related hip lesions. The purpose of the study was to propose the surgical strategy for hip disorders caused by long-term hemodialysis. METHODS: Patients with a history of hemodialysis for more than 10 years, 191 hip lesions in 165 consecutive patients who visited our institute due to hip symptoms. Various abnormalities were identified in 116 out of 191 hips. A retrospective assessment of the patient record and radiographs was performed for the included subjects examining the natural course of the disease process as well as the results of surgical treatment. RESULTS: Seventy-six hip lesions (69.0%) were conservatively managed at the time of the initial visit. Surgeries were performed for 75 hips (64.7%) during the study period. Among those, surgical treatment was indicated for 40 hips at the time of the initial visit. On the other hand, surgeries were performed for 35 hips during the subsequent follow-up period due to progression of the disease process. CONCLUSIONS: Based on the analysis of our surgical experiences by the retrospective chart review, we have established a flowchart of the treatment strategy for chronic hip arthropathy in long-term hemodialysis patients. STUDY DESIGN: This study is retrospective clinical study.

Assessment of Accuracy and Reliability in Acetabular Cup Placement Using an iPhone/iPad System.

Implant positioning is one of the critical factors that influences postoperative outcome of total hip arthroplasty (THA). Malpositioning of the implant may lead to an increased risk of postoperative complications such as prosthetic impingement, dislocation, restricted range of motion, polyethylene wear, and loosening. In 2012, the intraoperative use of smartphone technology in THA for improved accuracy of acetabular cup placement was reported. The purpose of this study was to examine the accuracy of an iPhone/iPad-guided technique in positioning the acetabular cup in THA compared with the reference values obtained from the image-free navigation system in a cadaveric experiment. Five hips of 5 embalmed whole-body cadavers were used in the study. Seven orthopedic surgeons (4 residents and 3 senior hip surgeons) participated in the study. All of the surgeons examined each of the 5 hips 3 times. The target angle was 38°/19° for operative inclination/anteversion angles, which corresponded to radiographic inclination/anteversion angles of 40°/15°. The simultaneous assessment using the navigation system showed mean±SD radiographic alignment angles of 39.4°±2.6° and 16.4°±2.6° for inclination and anteversion, respectively. Assessment of cup positioning based on Lewinnek's safe zone criteria showed all of the procedures (n=105) achieved acceptable alignment within the safe zone. A comparison of the performances by resident and senior hip surgeons showed no significant difference between the groups (P=.74 for inclination and P=.81 for anteversion). The iPhone/iPad technique examined in this study could achieve acceptable performance in determining cup alignment in THA regardless of the surgeon's expertise. [Orthopedics. 2016; 39(4):e621-e626.].

Use of the G-guide for Measuring Stem Antetorsion During Total Hip Arthroplasty.

Implant positioning is one of the critical factors influencing postoperative outcomes in total hip arthroplasty (THA). Several studies have reported that the postoperative antetorsion (AT) measurement for the femoral stem inserted without navigation showed wide variability. The current authors developed a simple instrument, the Gravity-guide (G-guide), for intraoperative assessment of stem AT and adjustment. They evaluated the effectiveness of the G-guide with postoperative computed tomography (CT) examination. Ninety patients (96 hips) who underwent primary THA using the G-guide for stem adjustment were evaluated. The G-guide consists of 2 parts: one attached to the lower leg and the other attached to the handle of the rasp. The G-guide was used to evaluate the AT at the time of inserting the final rasp. In addition, the AT value in the G-guide evaluation system required correction by the angle obtained in the preoperative epicondylar view. Intraoperative stem AT was defined as the sum of the intraoperative G-guide value and the correction angle. Postoperative AT was evaluated by CT examination. The discrepancy between the intra- and postoperative measurements was 4.6°±4.1°. Acceptable accuracy with discrepancy of less than 5° and 10° was achieved in 66 (69%) hips and 85 (89%) hips, respectively. The use of the G-guide could effectively reduce the variability of stem anteversion compared with manual adjustment. This study proved the effectiveness of the newly developed G-guide system in intraoperative stem AT adjustment.

Accuracy of combined anteversion in image-free navigated total hip arthroplasty: stem-first or cup-first technique?

PURPOSE: In total hip arthroplasty (THA), combined anteversion (CA) is used as a parameter for assessment of overall prosthetic alignment. The purpose of this study was to comparatively examine the CA value in patients who underwent primary THA using the image-free navigation system either with a cup-first or stem-first technique. METHODS: Eighty-three hips undergoing primary THA using the OrthoPilot® image-free navigation system (B. Braun-Aesculap, Tuttlingen, Germany) were included in this study. The patient population was divided into two groups depending on the procedure used: cup-first technique and stem-first technique. In the cup-first group, inclination and anteversion (AV) angles were targeted at 35-45° and 15-25°, respectively, while stem antetorsion (AT) was determined for each patient based on the amount of individual native femoral AT angle. In the stem-first group, the femur was prepared first with the target angle corresponding to the native femoral AT and the cup AV was decided considering the CA calculated with Widmer's formula (aiming at the optimal Widmer's CA of 37.3°). RESULTS: Better consistency in Widmer's CA values was attained in the stem-first group as indicated by the smaller SD values. In the assessment of overall alignment, Widmer's CA values were within the satisfactory range (37 ± 5°) in 41.9 and 92.3 % of the subjects in the cup-first group and the stem-first group, respectively. CONCLUSIONS: The stem-first technique with image-free navigated THA could effectively achieve accurate and consistent control of the CA value and thus is expected to improve the surgical outcome.

Histologic evaluation of the bone-ceramic interface of an alumina ceramic cup arthroplasty retrieved after 25 years in vivo.

A 47-year-old man underwent ceramic cup arthroplasty when he was 22 years old. Revision total hip arthroplasty was performed 25 years later because of limited range of motion without implant loosening. Histologic examination revealed that the femoral head and ceramic implant were well fixed through a thin fibrous membrane. The energy-dispersive X-ray analysis indicated that calcium and phosphorus were detected in the same peak pattern as cancellous bone in the bone-ceramic interface.

Surgical Treatment of Synovial Osteochondromatosis of the Hip Using a Modified-Hardinge Approach with a Z-Shaped Capsular Incision.

Synovial osteochondromatosis of the hip is a rare condition, and the surgical treatment approach for this condition requires complete removal of loose bodies combined with synovectomy. While these, procedures are generally accepted as the optimal treatment method, this is still controversial topic. Recent studies have reported that open surgical procedures remain acceptable for synovial osteochondromatosis of the hip. These procedures include the dislocation of the femoral head, and complications such as femoral head necrosis and bursitis or great trochanter non-union due to trochanteric osteotomy have been reported. The present study reports a modified technique for surgical dislocation through a Z-shaped capsular incision without trochanteric flip osteotomy for the treatment of synovial osteochondromatosis of the hip.

Significance of preoperative 3D-CT angiography for localization of the femoral artery in complicated THA.

BACKGROUND: Major vascular injury is one of the most devastating complications in total hip arthroplasty (THA). Risk for intraoperative vascular injury is increased when the normal vascular anatomy is distorted by previous surgery or dislocation with displacement. Therefore, an appreciation of the vascular anatomy in relation to the anticipated surgical field is critical to avoid this complication during preoperative assessment for a complicated THA. METHODS: Preoperative three-dimensional (3D) CT angiography was performed for 24 complicated THAs when altered vascular anatomy around the acetabulum was suspected. When assessing the CT images, the presence of apparent proliferation of vessels close to the original acetabulum as well as a distance of <10 mm from the artery to the acetabulum was deemed a potential risk factor for intraoperative vascular injury. Additionally, the relationships of clinical characteristics and the presence of these risk factors were analyzed to identify the patient population at risk. RESULTS: The incidence of proliferation of collateral vessels was higher in patient groups with proximal femoral migration of 5 cm or more and multiple previous surgeries prior to the index THA. Moreover, in three ankylosed hips, lateral deviation of the main vascular trunk with an artery-acetabulum distance of <10 mm was identified in all cases. CONCLUSION: Preoperative 3D-CT angiography in cases of complicated THA revealed altered vascular anatomy which may increase the risk for intraoperative vascular injuries. Patient characteristics related to the risk for this complication were marked proximal femoral migration, multiple previous surgeries, and hip ankylosis. Preoperative image examination of the vascular anatomy is thought to help reduce the risk of inadvertent vascular injury in these complicated THA cases.

Combined anteversion of the total hip arthroplasty implanted with image-free cup navigation and without stem navigation.

In total hip arthroplasty (THA), combined anteversion (CA), the sum of cup anteversion (AV) and stem antetorsion (AT) are used as parameters to assess the appropriateness of overall prosthetic alignment. In this study, we evaluated the CA value based on the post-operative computed tomography (CT) measurements in our patient population who underwent THA using the OrthoPilot™ image-free navigation system (B/BRAUN-Aesculap, Tuttlingen, Germany). During surgery, cup alignment was adjusted with the use of the navigation system while the positioning of the femoral stem was arbitrarily adjusted by the surgeon. Seventy-nine THAs were included in the study. Post-operative CT assessment for the prosthetic alignment showed the average cup inclination and AV values to be 40.5°±4.1° and 20.6°±4.6°, respectively, demonstrating the effectiveness of the navigation system by small values of standard deviation. By contrast, the AT value measured for the stem showed wide variability (mean 23.6°±11.2°). Consequently, the resulting CA was also inconsistent (mean 44.4°±11.2°) and only 61 of the 79 THAs (77.2%) were defined as satisfactory.

Radiological classification of hip arthropathy associated with long-term haemodialysis.

Various types of hip lesion associated with long-term haemodialysis have been observed. We present a new radiological classification system of haemodialysis-related hip arthropathy. In total, 103 hip lesions were analyzed in 84 patients undergoing haemodialysis for more than ten years. The hip lesions were classified into 3 types; Type I--cystic type with further subdivisions based on cyst location, Type II--arthritic type, and Type III--deformity of the femoral head. Surgery was performed on 60 hips. We believe our classification system assists decision making on behalf of these patients.

Femoral artery injury during revision of a dislocated bipolar hemiarthroplasty: a case report.

Although rarely encountered, major vascular injury is a serious complication of total hip arthroplasty (THA). We report the case of an 85-year-old woman who sustained a deep femoral artery injury associated with a superficial femoral artery thrombosis during revision of a dislocated bipolar hemiarthroplasty to a THA. Altered anatomy due to migration of the femoral head was thought to be one of the factors leading to this complication. Following the revision procedure, no signs of vascular insufficiency were detected in the immediate postoperative period, but ischaemia was clinically evident 12 hours after surgery. The importance of careful preoperative and postoperative assessment is addressed.