Short term prophylaxis against heterotopic bone after cementless hip replacement

The aim of the current study was to reveal whether 7 days of indomethacin treatment sufficiently prevents heterotopic ossification after cementless total hip arthroplasty. One group received indomethacin for 14 days (n = 102), and the second for 7 days (n = 99) after cementless total hip arthroplasty. At followup 1 year postoperatively, the average Harris Hip Score was 91 points in the 14-day treatment group and 89 points in the 7-day treatment group. The incidence of heterotopic ossification as outlined by Brooker was similar in both groups. Ninety-six patients in the 14-day treatment group had heterotopic ossification Grades 0 or 1, and 6 patients had Grade II heterotopic ossification; whereas in the 7-day treatment group, 95 patients had Grades 0 or 1 heterotopic ossification and 4 patients had Grade II ossification. None of the patients had Grades III or IV heterotopic ossification. In the 14-day treatment group, headache, dizziness, or gastritic disorders develop in 10 patients, and in the 7-day treatment group, 7 patients had these effects. This study shows that treatment with 100 mg indomethacin daily for 7 days is not significantly different than 14 days of treatment for the prevention of formation of severe heterotopic ossification after cementless hip arthroplasty.     

Long-term use of hearing aids in patients with presbyacusis

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.     

The Frank Stinchfield Award. Inhibition of heterotopic ossification with radiation therapy in an animal model

An animal model for the study of heterotopic ossification was developed and the effects of perioperative radiation were analyzed. In Phase I, New Zealand White rabbits (n = 18) underwent surgery either with or without muscle injury on each hip to establish the most reliable model in which to study heterotopic ossification. In Phase II, rabbits (n = 36) underwent either 400, 800, or 1200 cGy radiation to one hip 24 hours after bilateral hip surgery to establish a dose response relationship for postoperative radiation therapy. In Phase III, rabbits (n = 24) underwent preoperative radiation therapy (800 cGy) at 4, 16, or 24 hours preoperatively to investigate the mechanism of action and efficacy of preoperative radiation therapy. Monthly radiographs were graded by blinded observers for severity of heterotopic ossification. Mean grade, intraobserver and interobserver variability, and statistical significance were evaluated. In Phase II, 17 of 18 rabbits generated heterotopic ossification in both hips, and the mean grade of heterotopic ossification was always greater on the operative side with intentional muscle injury. Variability in the grading was considered excellent. Phase II revealed that 800 cGy was the minimal effective dose. Contrary to hypothesis, Phase III revealed an increasing grade of heterotopic ossification coinciding with a decreasing preoperative time interval, with the difference in heterotopic ossification grade with 24-hour versus 4-hour preoperative radiation being significant. The rabbit model is reliable and reproducible and closely resembles the human clinical situation after hip surgery. Preoperative and postoperative radiation effectively prevented heterotopic ossification formation. The results support the use of preoperative radiation and establish a need for additional investigation regarding the mechanism of action and timing of preoperative radiation therapy.     

Patient satisfaction and function after primary and revision total hip replacement

This study assessed and compared satisfaction and function before and after total hip replacement as reported by 531 patients who had primary and revision surgery and 1087 patients who had primary surgery only. All operations were registered by the Norwegian Arthroplasty Register during the years 1987 to 1993, with time from last surgery to followup ranging from 0.6 to 6.4 years. Sixty-one percent of the patients who underwent revision surgery and 84% of the patients who did not undergo revision surgery rated their overall satisfaction with the hip implant as good or very good. With adjustment for primary diagnosis, gender, age, bilaterality, and time since the primary operation, a substantial benefit of total hip replacement was observed in both groups with regard to pain, walking ability, and need of help. However, improvement was less among patients who underwent revision total hip replacement than among those who did not undergo revision surgery. A deterioration was seen among patients who underwent revision surgery with regard to employment status and exercise habits.     

Results of the total bi-metric cementless hip arthroplasty

A 2.9-year follow up of 50 primary Bi-Metric System cementless, porous-coated hip arthroplasties (Biomet) is presented. Four patients were operated bilaterally. In two patients, revision arthroplasty was carried out, in one because of infection, in the other because of loosening of the stem. The average Harris hip score was 96 points. The pain level according to d'Aubigné was 5.87. All patients belonged to Jensen's social function group 1. According to Engh's x-ray score, the femoral component achieved an average total of 19 points. Twenty-three patients with heterotopic ossification were graded according to Brooker et al; 18 patients belonged to group I-II, and 5 patients to group III. Discrepancy of leg length was measured in 20 patients, and averaged 0.52 cm (range: 0 cm to 2.5 cm). Four patients complained of thigh pain, but they had no radiographic evidence of loosening of components. The mean age was 63.4 years for women and 58.1 for men. Acceptably high Harris Hip Scores were obtained for the Bi-Metric hip prosthesis at 2-year follow up.     

Dislocation after total hip arthroplasty using the anterolateral abductor split approach

The three basic surgical approaches used most commonly in total hip arthroplasty are transtrochanteric, posterior, and anterolateral. Complications related to each of these surgical approaches have been reported including dislocation, trochanteric nonunion, heterotopic ossification, neurovascular damage, postoperative limp, and implant malalignment. The anterolateral abductor split approach previously has been reported to allow ease of access into the hip joint, optimum joint visualization, protection of neurovascular structures of the hip, and predictable results for postoperative hip function restoration. Reviewing a large consecutive series of primary total hip arthroplasty cases (1518), the authors report an overall dislocation rate less than 1% (12:1518; 0.79%). Stratified by preoperative diagnosis, patients undergoing total hip arthroplasty after trauma, or presenting with congenital dysplastic hip are at the highest risk for postoperative dislocation. Primary total hip arthroplasty using the anterolateral, abductor split approach can minimize the rate of postoperative dislocation in the prevailing preoperative diagnostic categories.     

Revision of failed cementless total knee implants with cement

Between 1986 and 1996, 268 revision total knee replacements were performed. Revisions for aseptic loosening were reviewed prospectively. Sixty-three patients had implants revised for aseptic loosening. Thirty-six of the patients had revisions of cemented constructs, whereas 27 of the patients had revisions of cementless constructs. The average time before revision for the cemented group was 86 months. The average time to revision for the cementless group was only 43 months. Fifty-two percent of the patients in the cementless group had revision of their implants within 2 years of their index arthroplasty. The average pain free interval for the cementless group was only 11 months with 63% of the patients having no pain relief after their index arthroplasty. The average postoperative score for the cementless group was 88, whereas the average postoperative score for the cemented group was 82. Revision of failed cementless total knee implants with cement is a reliable procedure. Results are similar to those of cemented knees revised with cement.     

Heterotopic ossification following total knee arthroplasty requiring surgical excision

We present a case of progressive heterotopic ossification (HO) after cementless total knee arthroplasty causing painful stiffness that was treated with surgical excision. The patient had few risk factors associated with HO, including minimal anterior notching and dissection of the distal femoral cortex. The patient did undergo manipulation; however, this occurred after the diagnosis of HO was made. This report documents a rare case of HO following total knee arthroplasty that required surgical excision.     

A modified direct lateral approach in total hip arthroplasty: a comprehensive review

A retrospective review of 770 consecutive primary total hip arthroplasties was conducted to determine the complications and utility of a modified direct lateral approach, which involves elevation of the anterior one-third of the gluteus medius and vastus lateralis in continuity. In 640 patients, 712 total hip arthroplasties were followed up for a minimum of 2 years (maximum 6.5 years, average 3.6 years). Two prosthetic dislocations occurred in the follow-up period, for a prevalence of instability of 0.3%. A moderate or severe limp was present in 10% of all patients at 2-year follow-up and in 4% of a subgroup of patients with only unilateral osteoarthritis of the hip (Charnley A). Severe heterotopic ossification (Brooker grade III or IV) developed in fewer than 3% of hips and was functionally limiting in only seven patients. Four sciatic nerve palsies occurred. Surgical exposure has been excellent through this approach, without the need for extensile measures, such as a trochanteric osteotomy. The duration of surgery has been considered acceptable, and the position of the components considered excellent while using this approach. From this review, it was concluded that this modified direct lateral approach has greatly diminished the potentially devastating complication of postoperative instability and is associated with an acceptable level and severity of limp and heterotopic ossification. The approach provides excellent exposure in primary total hip arthroplasty to allow accurate placement of components in an efficient manner.     

Antibiotic prophylaxis in Danish orthopedic alloplastic surgery

In order to assess the routine use of prophylactic antibiotics (AB) in arthroplastic surgery in Denmark, questionnaires were sent to all Danish orthopaedic departments and all general surgical departments that perform orthopaedic surgery. Fifty-six departments (93%) returned the questionnaires. All departments use prophylactic AB in primary knee and hip arthroplasty and in revision arthroplasty. In addition, all departments but one use prophylactic AB in arthroplasty secondary to osteosynthesis. The largest group of departments uses penicillinase-resistant penicillin (PRP) in their standard prophylaxis regimens. The second largest group uses second generation cephalosporins. With one exception, all use cefuroxime. A small group uses other types of AB. Fifteen percent of the departments combine systemic AB with gentamicin bone cement (GC) in primary hip arthroplasty, whereas 22% use this combination in primary knee arthroplasty. Significantly more departments use GC in revision arthroplasty (89%) and in arthroplasty secondary to osteosynthesis (63%). Prolonged antibiotic prophylaxis (beyond 24 hours) is practised to a significantly higher degree in revision arthroplastic surgery than in the primary arthroplasties. In conclusion, one of two homogeneous groups of prophylactic AB is used in arthroplastic surgery in Denmark as prescribed in the literature.     

Low dose flunarizine protects the fetal brain from ischemic injury in sheep

This retrospective long-term study analyzes the clinical function, failures, and radiographic status of 131 Richards Series 2 prostheses in total hip arthroplasties (THAs) performed during 1981 and 1982. After a minimum follow-up period of 11 years, the results were evaluated. Sixty two (54%) patients with 71 THAs were available for follow-up; 44 (38%) patients with 49 THAs had died. Three patients with three THAs were lost to follow-up, and seven patients with eight THAs were unable to participate in the examination due to causes not related to their present hip status. Ten patients underwent revision THA during the observation period. The median hip functional index (HFI) was 8.6 preoperatively and 15.8 at follow-up. Hip functional index correlated to radiographic signs of loosening. With revision as endpoint, the Kaplan-Meier survivorship for all 131 hips was 93% after 10 years and 91% after 12 years. The radiographic examination at follow-up revealed 5 (8%) definite loose cups and 12 (19%) definite loose stems. Including the number of aseptic loosened cups and stems confirmed at revision, aseptic loosening was found in 6% of all cups and 13% of all stems. This radiographic evaluation confirmed that lack of containment of the cup and varus position of the stem were factors influencing the long-term stability of the prostheses, whereas etiology, type of arthritis, and ectopic ossification did not. A fixation and stability score that was modified for cemented prostheses was developed and was of value in detecting the prostheses at risk. The long-term results of the Richards Series 2 THA are acceptable and comparable with other long-term studies on conventional prosthetic designs. Ten percent to 20% revision THAs due to aseptic loosening can be expected. In addition, patients younger than age 60 at surgery and especially men were found to belong to a high-risk group with regard to revision THA. These patients must be evaluated carefully so that revision THA can be performed before the bone bed is destroyed.     

Aseptic loosening of the femoral implant after cemented total hip arthroplasty in dogs: 11 cases in 10 dogs (1991-1995)

Aseptic loosening of the femoral implant (ALFI) was diagnosed in 10 dogs that had undergone cemented total hip arthroplasty (THA). One dog had bilateral ALFI. Loosening developed at the stem-cement interface a mean of 30 months after THA. The most common clinical sign was intermittent subtle or non-weight-bearing lameness. On radiographs obtained after THA, the distal stem tip was in contact with the cortical endosteum in all dogs. Radiographic changes at the time of diagnosis of ALFI included asymmetric periosteal reaction along the femoral diaphysis (n = 11), radiolucent zone at the stem-cement interface (6), altered implant position (4), and femur fracture (1). Surgical revision resulted in a good or excellent outcome in 9 dogs. In 1 dog, the implant became infected. In another, aseptic loosening recurred. Aseptic loosening of the femoral implant was significantly more common when initial positioning of the implant resulted in contact between the distal tip of the implant and cortical endosteum than when there was no contact.     

Animal models of heterotopic ossification

Heterotopic ossification is often a severe clinical complication of joint arthroplasty, neurologic trauma, and muscle injury. In rare genetic disorders, such as fibrodysplasia ossificans progressiva, heterotopic ossification can be crippling and often leads to premature death. Reliable animal models of heterotopic ossifications that mimic pathologies seen in man would be invaluable for the development of new treatments to combat heterotopic ossification. Various methods used to induce heterotopic ossification in animals including the use of bone morphogenetic proteins, urinary tract epithelia, and transformed cell lines are described. Genetic animal models of heterotopic ossification and various miscellaneous examples of heterotopic ossification in animals are described. Finally, the use of transgenic mice to manipulate bone morphogenetic protein expression is discussed as a possible future animal model of heterotopic ossification.     

The protective effect of a cut-resistant glove liner. A prospective, randomised trial

We performed a prospective, randomised study comparing the rates of glove perforation using double latex gloving with or without a disposable protective glove liner (Paraderm) on 118 patients undergoing primary or revision arthroplasty of the hip or knee by one surgeon (FRH). The patients were randomly allocated into two groups: in group 1 an inner and outer pair of latex gloves were worn as double gloves and in group 2 the glove liner was worn between the two latex gloves. There was glove perforation in at least one outer glove in 99 operations (84%). The operating surgeon was aware of the perforation in 21 of these. There were 22 perforations of the inner glove. Group 1 had a significantly higher perforation rate per operation (p < 0.05) than group 2. Our findings show that protective glove liners significantly reduce the rate of perforation of the inner glove during hip and knee arthroplasty.     

From the RSNA refresher courses. Total hip arthroplasty: radiographic evaluation

Expected appearances of total hip arthroplasty vary according to type of implant, its method of fixation (cemented, porous coating for bone ingrowth, press fit), and whether it is a revision. Cemented arthroplastic components normally may show 1-2-mm-wide radiolucent zones at cement interfaces. Definite loosening is diagnosed when progressive widening of the radiolucent zone, migration of a cemented component, or change in alignment is seen. In cementless arthroplasty, normal findings include calcar resorption, radiolucent zones up to 2 mm in width, cortical thickening, periosteal reaction, endosteal sclerosis, and even subsidence of the femoral component that stabilizes at less than 1 cm. The most reliable radiographic signs of loosening in cementless arthroplasty are progressive subsidence, migration, or tilt of the component. Because subsidence or change in alignment may be very subtle, serial radiography and measurement are often required for diagnosis. Other signs that indicate loosening include bead shedding (in porous-coated prostheses), extensive cortical hypertrophy, endosteal bone bridging at the stem tip, endosteal scalloping, and a radiolucent zone wider than 2 mm. In revision arthroplasty, wide radiolucent zones and subsidence are common. The diagnosis of revision failure is based on progressive widening of the radiolucent zones and change in component position after 12 months.     

Long-term results of total hip replacement in young patients who had ankylosing spondylitis. Eighteen to thirty-year results with survivorship analysis

We determined the long-term results of total hip replacement in a series of young patients who had ankylosing spondylitis. Between 1966 and 1978, forty-three Charnley low-friction arthroplasties were performed in twenty-four patients who had an average age of 28.8 years (range, nineteen to thirty-nine years) at the time of the operation. There were seventeen men and seven women. The average duration of follow-up for the series was 22.7 years (range, one month [a perioperative death] to 30.3 years). Four patients (seven hips) had died an average of 12.6 years (range, one month to 18.7 years) after the operation. The twenty surviving patients had clinical and radiographic follow-up until the time of writing or until both of the original components had been revised. All patients had substantial relief of pain and improvement of function and the range of motion of the joint. Twenty-one patients (88 per cent; thirty-nine hips) were completely free of pain (6 points, according to the scale of Merle d'Aubigne and Postel), and the remainder had only slight discomfort (5 points). Ten acetabular components and one femoral component were revised because of aseptic loosening, and one patient had a revision of both components because of late deep infection. Three additional femoral components were revised during a revision operation for a loose acetabular component. Although the femoral components were not loose, they had been in place for more than ten years and it was thought likely that the bearing surface was damaged. The average time to revision was 13.3 years (range, 4.0 to 20.3 years). At an average of 22.7 years, thirty-eight (88 per cent) of the original femoral components and thirty-two (74 per cent) of the original acetabular components remained in situ. The average annual rate of acetabular wear was 0.12 millimeter for the entire series. Only six hips (14 per cent) had minor heterotopic ossification, and none of the hips had clinically important ossification (class III or IV according to the system of Brooker et al.). To our knowledge, the present report describes the largest series of total hip arthroplasties, with the longest duration of follow-up, in young patients who had ankylosing spondylitis. Survivorship analysis with use of the Kaplan-Meier method revealed that the probability of survival of the femoral component (with 95 per cent confidence intervals) was 91 per cent (83 to 99 per cent) at twenty years and 83 per cent (72 to 94 per cent) at thirty years. The probability of survival of the acetabular components was 73 per cent (61 to 84 per cent) at twenty years and 70 per cent (57 to 83 per cent) at thirty years. The probability that both components would survive was 91 per cent (82 to 100 per cent) at ten years, 73 per cent (61 to 84 per cent) at twenty years, and 70 per cent (57 to 83 per cent) at thirty years. The Charnley low-friction arthroplasty provided consistently good long-term results, with a low rate of complications and revisions, in this group of young patients.     

Total hip replacement arthroplasty in the Netherlands

The total hip arthroplasty (THA) is an effective treatment of osteoarthritis of the hip joint. Each year, more than 16,000 THAs are performed in the Netherlands. The incidence of THA had doubled between 1980 and 1994. The medical indication has extended to younger and older patients. Due to the success of the THA the number of alternative treatments, such as arthrodesis and osteotomy decreased. The number of revision surgeries increased more than four folds, to 1,400 in 1994. Based on these data the increase of primary and revision hip arthroplasties is expected to continue, but it is unknown how much the exact increase will be. In view of the increased demand it is important to gain more insight into the numbers of primary and revision surgical procedures to be expected, so that a better estimation can be made of the health care capacity and financial resources required in the future.     

Granular histiocytosis of pelvic lymph nodes following total hip arthroplasty. The presence of wear debris, cytokine production, and immunologically activated macrophages

Infiltration of regional lymph nodes by macrophages has been demonstrated after total joint arthroplasty. Although lymph nodes regulate the immune response, neither cytokine production nor the degree of immunological activation of cells within these nodes after total joint arthroplasty has been investigated. Pelvic lymph nodes were obtained from five patients who had had a total of eleven arthroplasties in seven hips three to twenty years before a pelvic staging procedure for adenocarcinoma (of the prostate in four patients and of the endometrium in one). All lymph nodes had polyethylene or metal debris as well as effacement of the normal nodal architecture by a histiocytic infiltrate. These changes were bilateral in the patients who had had an arthroplasty of one hip. Analysis of specimens from pelvic lymph nodes on the side of the involved hip demonstrated intense immunohistochemical staining of histiocytes for the major histocompatibility complex class-II antigen HLA-DR, a marker of histiocyte immune activation. In contrast, staining was absent in specimens from the contralateral lymph nodes as well as in those from seven patients who had had a prostatectomy but not a hip arthroplasty. Immunohistochemical staining for interleukin-1beta, tumor necrosis factor-alpha, and interleukin-6 demonstrated a much greater expression of these cytokines in the involved lymph nodes. Clinical relevance: Additions improvements in total joint replacement will be facilitated by a more thorough understanding of the biological response to the components and materials of implants. While local biological factors leading to failure of prostheses are currently under intense investigation, the mechanisms and importance of regional and systemic immune responses to wear debris require further study.     

A histologic and biochemical comparison of the interface tissues in cementless and cemented hip prostheses

Thirty-four membranes from 20 cementless and 14 cemented prostheses from 33 patients excised during revision arthroplasty were analyzed for foreign-body reactive processes. As a control, identical analyses were performed using adjacent pseudocapsular tissue taken from 12 patients during revision arthroplasty. Histologically, cementless membranes tended to contain more metal debris, and cemented membranes contained more foreign-body giant cells. Collagenase, gelatinase, prostaglandin E2, and interleukin-1 were measured in conditioned media taken from organ cultures of each interface membrane. Both cementless and cemented membranes released significant levels of gelatinase and collagenase, prostaglandin E2, and interleukin-1 into the conditioned media when compared with control tissues. However, the tissue concentrations were not significantly different between cementless and cemented membranes. Although histologic differences between cementless and cemented interface membranes exist, both share a similar capacity to release bioactive products that can induce bone resorption and cause aseptic loosening of the hip prostheses.     

Survivorship analysis of cemented total hip arthroplasty acetabular components implanted with second-generation techniques

The clinical and radiographic results of primary cemented total hip arthroplasty performed by a single surgeon, with particular emphasis on the performance of acetabular components implanted with so-called second-generation cement techniques, were studied. Seventy hips with 48 metal-backed and 22 polyethylene acetabular components were followed for a mean of 9 years (range, 5-11.5 years). The clinical results were evaluated using a recognized hip score. The fixation status of the cemented acetabular component was evaluated using two methods of measuring radiolucent lines at 5 years and at the last evaluation. Acetabular component loosening was defined as a circumferential radiolucent line, component migration, or revision for loosening. This study was unable to confirm the findings of others that demonstrated higher failure rates with cemented metal-backed components when compared with all-polyethylene components. The survival of cemented acetabular components with 28-mm head femoral prostheses was worse than the survival of cemented acetabular components with 22-mm femoral heads in other published reports, despite advances in cement techniques. Because of the high rate of loosening of cemented 28-mm-inner-diameter acetabular components at 5 and 10 years, the authors no longer use these cemented components for acetabular reconstruction.