Implantation Of Hip Endoprosthesis Research Articles

Efficacy of Alendronate in Preventing Periprosthetic Bone Loss after Implantation of a Primary Hip Endoprosthesis

Total hip arthroplasty (THA) is now the gold standard for the surgical treatment of coxarthrosis. The appearance of bone loss after implantation of the hip endoprosthesis over time reduces the primary stability of the implant and leads to progressive looseningof the implant, or periprosthetic fracture, which are considered to be the most common causes of hip revision.
 The aim of this study is to evaluate the value of alendronate application in reducing periprosthetic osteolysis reduction after implantation of total cementless hip endoprosthesis.
 The study analyzed 50 patients operated on with implantation of a cementless total hip arthroplasty (THA). The first group of 25 patients recieved oral alendronate, calcium and vitamin D3 postoperatively. The second group of 25 patients were examined and followed postoperatively without any therapy.
 Patients were examined by RTG and DXA methods at 6, 12 and 18 months.
 The study showed a difference in the values of bone mineral density (BMD) and bone mineral content (BMC) in the interval of 6,12 and 18 months, using the DXA method.
 Alendronate therapy after total hip implantation reduces periprosthetic bone loss, maintains bone mineralization and strengthens the implant

Two stage revision hip arthroplasty in periprosthetic joint infection. Comparison study: with or without the use of a spacer

PurposeThe aim of this study was to compare two methods of two-stage surgery for PJI (periprosthetic joint infection) after THA (total hip arthroplasty): one with and one without the use of an antibiotic-loaded cement spacer.MethodsThis retrospective study was performed on 99 consecutive patients (99 hips) with a minimum follow-up of 24 months. Patients were divided into two groups: (1) in whom the operation was performed using a spacer, and (2) for whom a spacer was not used.ResultsFor the whole cohort, the results improved between pre-operative and final follow-up. Recurrence of infection was found in nine out of 98 patients (9.2%) and was not significantly different between the two groups. Patients treated with a spacer had better functional improvement in the interim period, but the VAS score was better in the non-spacer group. The improvement in final function was better in the spacer group with regard to HHS, but not according to WOMAC score or VAS at final follow-up.ConclusionThe resection arthroplasty should be awarded particular consideration in cases of poor soft tissue quality, bone stock deficiency, when complications related to spacer use are expected or chances of new hip endoprosthesis implantation are low.

A Typical Case of Paradox Cerebral Embolism during Cemented Total Hip Arthroplasty

It is known that implantation of hip endoprosthesis, especially when cemented, is accompanied by the risk of fat embolism to the pulmonary circulation. We here report the case of a paradox embolism in a patient with a persistent foramen ovale in the heart. A 77-year old man with a known multiple myeloma fell on his hip and suffered a femoral neck trochanteric fracture (AO 31.B3). A cemented total hip arthroplasty was performed and the greater trochanter was stabilised by cerclage. After surgery, slurred speech and a deviation of the eyes were observed. Magnetic resonance imaging (MRI) of the brain showed ischemia in the dorsal flow area of the cerebellum on both sides, especially in the pica flow area, the left thalamus, left temporal and occipital due to multiple embolisms. Trans esophageal echocardiography showed a persistent foramen ovale (pfo) with free flow. Intensive specialized physio and ergotherapy was initiated with good results. Upon control three and a half years later the patient showed no neurologic sequelae and a stable hip prosthesis.

Different Types of Hip Endoprostheses after Osteoporotic Femoral Neck Fracture; Functional Results?

Aim of this study was to recognize differences in long-term clinical outcome after femoral neck fracture and hip endoprosthesis implantation. Total of 145 patients were examined, 32 patients with unipolar, 70 with bipolar and 43 patients with total hip endoprosthesis. The mean values of Harris hip score, after 3.8 ± 1.9 years, were: 72.1 ± 17.8, 74.27 ± 19.1, 78.2 ± 22.5 for patients with unipolar, bipolar and total hip endoprosthesis, respectively. No statistically significant difference was observed (p=0.704). The in-hospital mortality rates were: 4.3%, 4.6%, and 5.3% for groups of patients with bipolar, unipolar and total hip endoprosthesis, respectively. Considering clinical outcomes, general health and costs, it could be concluded that choice of endoprosthesis does not pose an obstacle in patient’s recovery.

Surgery and sepsis increase somatostatin-like immunoreactivity in the human plasma

We have previously shown in animals that somatostatin released from capsaicin-sensitive afferents in response to inflammation and tissue damage exerts systemic anti-nociceptive and anti-inflammatory actions. Since peptidergic sensory innervation of the airways and the joints are particularly dense, we aimed at investigating the alterations of plasma somatostatin-like immunoreactivity (SST-LI) in response to thoracic and orthopedic surgery, as well as sepsis. Thoracotomy, video-assisted thoracoscopy, hip and knee endoprosthesis were performed under general anesthesia. Blood was taken before, during and after the surgical procedures, as well as at admission and every consecutive morning from septic patients receiving exclusively total parenteral nutrition. SST-LI was determined from the plasma with specific and sensitive radioimmunoassay developed in our laboratory. Plasma SST-LI in healthy volunteers and preoperatively was 8–12 fmol/ml. Both thoracotomy and thoracoscopy significantly increased SST-LI by 55–60% at the end of the procedures when the thoracic cavity and the skin were closed. Hip endoprosthesis implantation elevated SST-LI by 30% after skin incision, which increased further to 55% by the time the surgery was completed. In contrast, knee operations performed under tourniquet did not alter SST-LI in the systemic circulation. SST-LI was almost 3-fold higher in the plasma of septic patients than in healthy volunteers. This human study revealed that thoracic/hip surgery and sepsis elevate SST-LI in the systemic circulation, presumably by inducing its release from sensory fibres. It is concluded, that the endogenous protective mechanism mediated by neural somatostatin, which has been evidenced in animals, is likely to operate in patients.

Prevention of para-articular ossifications by radiotherapy after cementless total hip endoprosthesis implantation

By means of a prospective study, concerning the postoperative rate of ossification after cementless total hip replacement, it was due to prove the efficacy of radiotherapy in preventing periarticular ossification. In 1992 arthroplasty was followed by radiotherapy of 50 hip joints as regular therapy. The radiation was performed with a focal dose of 8 Gy. Patients with bilateral cementless total hip replacement and radiotherapy only at one side were of special interest in this study. Within the 24th postoperative week in 28 (56%) of the radiated hip joins no periarticular ossifications were found. In 20 (40%) we found ossifications grade 1, in 1 case ossification grade II and in 1 further case ossification grade III following the classification of Arcq. By 8 patients with former cementless total hip replacement without postoperative radiotherapy, a significant reduction of the ossification rate was found in the contralateral hip joint treated by postoperative radiotherapy. The rate of ossification was reduced by 28%. In correlation to reduction of periarticular ossification the increase on the overall range of motion in the radiated hip joins was 10.9%. By none of the patients treated by radiotherapy we found a disturbed healing process, a deep infection or an early loosening of the endoprosthesis. Postoperative radiotherapy as regular therapy for prophylaxis of periarticular ossification after Cementless total hip replacement can subsequently be recommended.

Predicting Patient’s Long-Term Clinical Status after Hip Arthroplasty Using Hierarchical Decision Modelling and Data Mining

Construction of a prognostic model is presented for the long-term outcome after femoral neck fracture treatment with implantation of hip endoprosthesis. While the model is induced from the follow-up data, we show that the use of additional expert knowledge is absolutely crucial to obtain good predictive accuracy. A schema is proposed where domain knowledge is encoded as a hierarchical decision model of which only a part is induced from the data while the rest is specified by the expert. Although applied to hip endoprosthesis domain, the proposed schema is general and can be used for the construction of other prognostic models where both follow-up data and human expertise is available.

5- to 8-year results of total hip endoprosthesis implantation with the Müller straight shaft prosthesis (cemented TiAlNb shaft)

The aim of this study was to obtain mid-term results after total hip arthroplasty (THA) with cemented titanium stems. In all, 184 patients with a total of 202 THAs (cemented titanium stem) were clinically and radiologically examined after an average follow-up of 6 years (5-8). The recruitment was 86%. The Harris score was determined clinically. Radiologically, the directly postoperative radiographs were compared to the control radiographs according to the recommendations of Gruen et al. and Johnston et al. In 2 cases (1%) septical complications appeared after 2 years, which were treated in two-stage surgery. To date, revisions after loosening have been carried out in 3 cases (1.5%). This is equivalent to a revision rate of 2.5%. Three further cases showed evidence of loosening in more than 5 radiolucent lines (RLL), according to Gruen, making close-meshed controls necessary. Clinically, in all of the 6 cases of aseptic loosening, the Harris score remained above 80 points. In 36 cases, more than one RLL, compared to the postoperative radiographs, was ascertained and mainly found in zones 1, 7, 8, and 14. Substantial subsidence or varus could only be observed in one case. The clinical results in the Harris score were good or excellent in 78% and satisfactory in 20%. With an average of 75 at the time of follow-up, the age of the patients was, according to the indication that only patients above age 60 are to receive cemented-stem prostheses, clearly advanced. The body weight was significantly higher (82 kg; d = 2.4) in those 6 patients having evident RLL, than in patients without RLL. The ratio body weight to surface of the stem was especially different (1.5 kg/cm2 versus 1 kg/cm2; P < 0.005) in the two groups. This did not apply to sex or activity of the patient, size or kind of stem, Harris score, ectopic ossification, or body weight index. The biggest possible stem should be implanted. Not all cemented titanium stem prostheses are necessarily affected with a high rate of loosening at a mid-term follow-up.

C-reactive protein as an early indicator of the formation of heterotopic ossifications after total hip replacement.

The formation of heterotopic ossifications after total hip endoprosthesis implantation is a well-known complication. During the postoperative course laboratory parameters are subject to partial change due to the development of heterotopic ossifications. However, these changes occur relatively late at a time when the application of prophylactic precautions is usually already decided. Any meaningful prophylactic treatment, however, has to be initiated immediately after surgery. In a prospective study we assessed the postoperative C-reactive protein (CRP) levels in 95 patients twice after total hip replacement surgery. The initial assessment took place on the 1st day following surgery and again between the 5th and 7th day. All patients received three doses of 50 mg diclofenac daily for 7 days starting on the 1st postoperative day. Average CRP values on the 1st postoperative day were 6.33 +/- 2.28 mg/dl for ossification grade Brooker 0, 7.04 +/- 1.8 mg/l for Brooker 1 and 7.65 +/- 3.7 mg/dl for Brooker grades 2-4. At the time of the second CRP assessment (postoperative day 5-7), CRP values in the groups of patients showing ossifications were higher. Whereas patients without ossifications (A) exhibited an average level of 4.22 +/- 3.13 mg/dl, in patients with ossification grade 1 (B) CRP was 5.57 +/- 2.78 mg/dl and in the group with ossification grades 2-4 (C) was 6.38 +/- 4.48 mg/dl. The differences between group A on the one hand and the combined groups B and C values on the other were significant (P = 0.036). We are able to assert that after total hip replacement, significantly higher CRP levels can be recorded immediately after surgery in those patients who will eventually develop heterotopic ossifications, as compared with those who do not. Hence, the postoperative rise of CRP levels should be introduced as a further risk factor for the formation of heterotopic ossifications since its recording at such an early stage still allows for the timely initiation of prophylactic treatment.

Computer-assisted robotics in hip endoprosthesis implantation

The most important prerequisite for permanent fixation of an implant is primary stability. Osteointegration of the implant is a major goal in cementless total hip replacement (THR). This means direct contact between bone and implant leading to fixation of the implant in the bone without the interference of fibrous tissue. In addition to the design of the implant, the structure of the implant surface and the material of the implant, the specific operational technique plays a major role in permanent fixation. Only the conical fixation of femoral implants guarantees high primary stability in cementless THR. The type of fixation of the implant in the femoral cavity and the resulting load transfer from implant to bone has a decisive effect on the durability of the prostheses. In order to achieve optimal primary fixation of the implant, robot-assisted implantation of the cementless implant has been performed at the Berufsgenossenschaftliche Unfallklinik Frankfurt am Main since the summer of 1994. After preoperative planning at a three-dimensional graphic work station these data are transferred to the robot, which transforms the preoperative planning by milling the femoral cavity with the highest precision. So far this type of surgery has been performed on 300 patients. The encouraging postoperative results prompted us to install the second system of Robodoc at the Berufsgenossenschaftliche Unfallklinik Frankfurt.