A cadaveric study to assess the accuracy of computer-assisted surgery in locating the hip center during total knee arthroplasty

Computer-assisted technology allows the accurate location of inaccessible landmarks such as the center of the hip in total hip arthroplasty. Using 7 fresh normal cadaveric hips, we conducted 2 studies. The first study compared iliac (A) vs no iliac (B) tracking. The second study assessed the reliability of the hip center acquisition using the range of hip motion during manipulation. The first study revealed no statistical difference between the 2 techniques A (mean, 0.67; SD, 0.15) and B (mean, 0.66; SD, 0.32) used to locate the center of the hip. In the second study, a range of motion less than 10 degrees negatively affected accuracy. Using this technology, without an iliac tracker, allows accurate and precise determination of the center of the hip.     

Radiographic determination of the anatomic hip joint center: A cadaver study

We studied 31 human pelvic cadaver specimens with 57 intact hip joints. The teardrop, which represents the inferior portion of the acetabular notch, was identified as also was the center of rotation in the articulating femoral head. The pelvic height and the horizontal and vertical distances between the acetabular notch and the hip joint center were measured. We found the center of rotation of the hip joint to be 13 percent of the pelvic height lateral and 7 percent of the pelvic height superior to the teardrop. No sex difference was found.     

An algorithm for locating the center of the ankle joint in knee navigation surgery.

The primary aim of computer-assisted knee arthroplasty is to improve the alignment of the implanted prostheses. Accurate component alignment is dependent on the establishment of accurate anatomical reference points. Current techniques for establishing the center of the ankle joint, especially in the coronal plane, rely solely on clinical judgment in relation to the position of the center of the ankle joint. The aim of this study was to determine if an algorithm could be developed, based on establishing the most prominent points on the medial and lateral malleoli on 3D CT scans, to accurately and reproducibly establish the position of the center of the ankle joint. To determine this, images of 20 ankles were obtained and axial, coronal, and sagittal 2D reconstructions were manipulated on a workstation. Two observers independently performed relevant measurements and calculations. The calculated data was found to be reproducible with a very small standard deviation in each plane. This algorithm is able to provide accurate measurements of the ankle joint in knee navigation surgery. Caution must be exercised in anatomically abnormal ankles, as the calculations of the ankle center were found to be significantly different.     

全髋关节置换术髋臼旋转中心的回顾性研究

[目的]通过手术前后对髋臼旋转中心的X线测量，探讨髋臼旋转中心的变化对髋关节平衡稳定性的影响。[方法]追溯调查近年本院收治120例155髋，均为首次行全髋关节置换术患者，对比术前术后双髋关节正位X线片，比较术后髋臼假体的旋转中心（HJC1）与解剖髋臼旋转中心（HJC0）的符合率。[结果]旋转中心恢复者98髋（63．23％）（A组），未恢复者57髋（36．77％）（B组）；A、B两组中因人工髋关节松动、脱位、髋部痛等行髋关节假体翻修术分别为6髋（6．12％）、17髋（29．82％）。[结论]髋臼旋转中心的恢复对人工髋关节置换术后的关节稳定性有直接影响。     

Arthroscopic surgery of the hip joint

Hip arthroscopic examination of 196 joints was performed in 104 patients treated during the past 4 years. Of these, 11 joints were treated by arthroscopic surgery. We have developed a technique using a two-directional approach that facilitates a global view of joint areas and allows simpler performance of surgical procedures. Removal of loose bodies, joint debridement in osteoarthritis, and synovectomy in rheumatoid arthritis are good indications for arthroscopic surgery of the hip joint. Short-term follow-up was satisfactory, and a reduction of pain was obtained in all patients. Although the joint space of the hip is narrower and the operative technique is more difficult to perform than in the knee, we believe that arthroscopic surgery of the hip is a suitable method in selected cases.     

Iatrogenic arterial trauma associated with hip joint surgery: an overview

Four cases of iatrogenic arterial injuries following hip surgery are reported. An overview of the literature revealed 122 additional cases. In 93 (74%) of these cases the arterial damage occurred following total hip replacement, 27 (21%) were related to hip fracture correction and six cases complicated other hip surgery procedures. Revisional hip surgery was found to be a definite risk factor. Injuries associated with hip replacement differ significantly in various characteristics of those associated with hip fracture correction. There was a 9% mortality and a 17% permanent disability rate in patients with arterial trauma following total hip replacement. In this group a significantly higher permanent disability rate was noticed in patients who first presented with ischaemia (p less than 0.05). No relationship between the location and mechanism of injury and the outcome was found. Mortality and permanent disability rates of 4% and 11%, respectively, were noticed in patients with injuries related to hip fracture correction.     

Alignment of computer-assisted total knee arthroplasty in patients with altered hip center

This study aimed to determine limb and component alignment after computer-assisted total knee arthroplasty in 30 patients (32 limbs) with an altered hip center due to a prior hip implant or deformed femoral head. There were no outliers greater than ±3° in the postoperative coronal alignment of the limb and the femoral component in relation to the altered hip center. Two limbs (8%) were more than ±3° for coronal alignment of the femoral component in relation to the anatomical hip center and 96% of limbs had less than 2° deviation in relation to the altered hip center. Computer-navigated total knee arthroplasty results in accurate restoration of lower limb and component alignment in patients with prior hip implants or deformed femoral heads where accurate restoration of alignment may be challenging due to altered hip center.     

Vascular complications in surgery of the hip joint

The mechanisms of severe vascular injury during surgery of the hip joint are depicted with reference to the authors' own patient series and a review of the literature. Massive arterial hemorrhage is most commonly caused by the tip of a Hohmann retractor. Special care must be given to placement of the proximal retractor directly against the pelvis behind the anterior lip of the acetabulum, and this must be checked with the finger tip. Other mechanisms of injury are: massive venous bleeding can result if a coil of pelvic vein is rolled up with a Kirschner wire; arterial thrombosis can be caused by the polymerization heat of bone cement; or intimal dissection can be caused by pressure of a retractor or loosening of an intimal plaque, resulting in ischemia of the corresponding limb; arterio-arterial embolism can originate from appositional thrombus formation on a chronically weakened arterial wall; false aneurysms may be due to instrumental arterial injury; and arteriovenous fistulae can be caused by a piercing instrument. Laceration of the external iliac or common femoral artery is best treated by interposition of a saphenous vein graft. Angiological examination before and immediately after hip surgery is advocated.     

Mechanoreceptor evaluation of hip joint capsule and ligamentum capitis femoris in developmental hip dysplasia: a preliminary study

We aimed to determine if there are mechanoreceptors in the hip joint capsule and ligamentum capitis femoris (LCF) of patients with developmental dysplasia of the hip (DDH). We took capsule and LCF biopsies from 20 hips of 20 patients who were operated on because of DDH. The mean age was 10.2 months (range 6-20 months) at the time of surgery. There were 12 girls and eight boys. Teratologic and secondary hip dislocations were not included in this study. Full thickness, 0.5 x 0.5 cm anterior capsule and LCF portions were taken for biopsy specimen. Specimens were stained with hemotoxylin eosin and examined immunohistochemically using monoclonal antibody against S-100 protein. In both analyses no mechanoreceptor was found in any samples of capsule or LCF. In this preliminary study we could not find mechanoreceptors in the local anterior joint capsule and LCF of the hip in children with DDH. We think that additional studies are necessary in order to understand the mechanoreceptor characteristics of the hip joint in children not only with DDH but also in children with healthy hips.     

Aspiration arthrography of the hip joint: Its uses and limitations in revision hip surgery

Seventy-one patients undergoing revision hip surgery over a 5-year period from 1988 to 1993 had aspiration arthrography of the hip as a preoperative investigation. Sixteen hips were found to be infected at operation. Preoperative aspiration yielded positive cultures in 11 of these 16 hips. There was identical correlation between the organisms isolated on aspiration and during surgery. There were 5 false positive cultures from the aspirates of the remaining 55 noninfected hips. All of the hips from which a true positive culture was obtained had either clinical or radiologic evidence suggestive of infection. Aspiration arthrography does not have a major role to play as a routine investigation prior to all revision hip surgery. It is recommended that its use be reserved for those hips in which there is either clinical, hematologic, or radiologic evidence of infection.     

Antibiotic prophylaxis in allo-arthroplastic hip joint surgery

Summary The indication and the efficacy of antibiotic prophylaxis in endoprosthetic operations are discussed with reference to prospective studies.After parenteral administration of 80 mg gentamicin the antibiotic concentrations in the serum and in the wound exudate were studied for 2 to 6 hrs after administration. During this observation period the gentamicin concentrations in the wound exudate were about equal to those in the serum.A comparison of the concentrations after parenteral and after local administration of gentamicin showed much higher concentrations in the wound exudate when gentamicin was administered with the bone cement.

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Antibiotische Prophylaxe bei allo-arthroplastischen HüfteingriffenKonzentrationsbestimmungen im Wundsekret nach parenteraler Verabreichung von Gentamycin

Zusammenfassung Anhand prospektiver Untersuchungen werden die Indikation und Wirksamkeit einer Antibioticumprophylaxe bei Endoprothesenoperationen erörtert.Nach parenteraler Gabe von 80 mg Gentamycin wurden für 2–6 Std nach der Applikation die Wirkstoffkonzentrationen im Serum und Redonsekret untersucht. Während des Beobachtungszeitraumes entsprachen die Gentamycinkonzentrationen im Wundsekret in etwa den Serumkonzentrationen.Ein Vergleich der Konzentrationen nach parenteraler und lokaler Gentamycinapplikation zeigte wesentlich höhere Wundsekretkonzentrationen, wenn Gentamycin mit dem Knochenzement verabreicht wurde.

     

Contact study of the hip joint

Summary 1. Contact study of the human hip joint was performed in order to understand load-deformation pattern under compressive loading, contact area and contact pressure by our method. 2. Weight-bearing function of the hip joint was confirmed. Deformation of articular cartilage and subchondral bone were made reasonably and joint congruity was considered to be obtained with increasing load. 3. Neither contact area nor distribution of the contact pressure were symmetrical or concentric, and both were dependent on the magnitude of load. 4. The relationship between weight-bearing and early cartilage degeneration was discussed.

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Zusammenfassung 1. Belastungsuntersuchungen des menschlichen Hüftgelenkes wurden durchgeführt, um einen Einblick zu gewinnen in die Belastungsverformung des Gelenkes unter Druckbelastung, sowie um eine Information zu erhalten über die Belastungsflächen und deren Druckbeanspruchung. 2. Die lasttragende Funktion des Hüftgelenkes wurde bestimmt. Die Belastungsdeformation des Gelenkknorpels und des subchondralen Knochens wurde dargestellt und es wurde festgestellt, daß mit zunehmender Belastung eine Verbesserung der Gelenkkongruenz erreicht wird. 3. Weder die Kontaktfläche noch die Druckverteilung waren symmetrisch oder konzentrisch, und beide waren abhängig von der Größe der Belastung. 4. Die Wechselbeziehungen zwischen Belastung und vorzeitiger Knorpeldegeneration werden diskutiert.

     

股骨偏心距和髋臼旋转中心对人工全髋置换术后关节功能影响的回顾性研究

[目的]通过股骨偏心距及髋臼旋转中心手术后测量,探讨其变化对人工全髋置换术后关节功能的影响。[方法]临床随访本院人工全髋置换术后患者87例(92髋),均为首次行全髋关节置换术患者,平均随访时间2年1个月,测量手术后双髋关节X线片,比较术后假体股骨偏心距、旋转中心与解剖股骨偏心距、旋转中心符合率,对患者术后髋关节功能进行Harris评分并分组进行统计学分析。[结果]股骨偏心距及髋臼旋转中心均恢复(A组)27例(29.35%),(B组)仅FO恢复23例(25.00%),(C组)仅HJC恢复31例(33.70%),(D组)FO及HJC均未恢复11例(11.96%),Harris评分优良率A组96.30%,B组为73.19%,C组为74.19%,D组为27.27%,Harris评分优良率A组与B组(P=0.039),A组与C组(P=0.029),A组与D组(P=0.000)差异均有统计学意义。[结论]股骨偏心距及旋转中心的恢复对人工全髋置换术后关节功能有直接影响。