Percutaneous intramedullary screw or rush pin fixation of unstable ankle fractures in patients with fragile soft tissue - retrospective study of 80 cases.

INTRODUCTION: The standard surgical procedure for unstable ankle fractures is fixation of the lateral malleolus with a plate and screws. This method has a high risk of complications, especially among patients with fragile skin conditions. The aim of this study was to estimate the re-operation rates and identify complications in patients with an unstable ankle fracture, surgically treated with an intramedullary screw or rush pin. MATERIALS AND METHODS: We identified all patients who were surgically treated with either a 3.5-mm screw or rush pin at Aarhus University Hospital, Denmark, from 2012 to 2018. Major complications were re-operations within three months. We included 80 patients, of which 55 (69%) were treated with a 3.5-mm intramedullary screw and 25 (31%) with a rush pin. The majority of the study population was female (59) and the mean age was 75 (range 24 to 100) years. Of the 80 patients included, 41 patients had more than 2 comorbidities. RESULTS: Three patients underwent re-operation within three months due to either fracture displacement or hardware cutout. Radiographs obtained after six weeks showed that nine patients had loss of reduction. Additionally, four patients had superficial wound infections and six patients had delayed wound healing. CONCLUSIONS: Intramedullary fixation of distal fibula fractures with either a screw or rush pin has low re-operation rates. However, the high proportion of patients with radiological loss of reduction is concerning.

Dislocation rate, revisions and other complications of primary cemented hemiarthroplasty for displaced femoral neck fractures: a single-center cohort study of 743 unselected hips with a mean 2.7-year follow-up.

INTRODUCTION: Evidence of whether to use hemiarthroplasty (HA) or total hip arthroplasty for displaced femoral neck fractures (FNF) is still widely debated, especially when taking ambulatory status, age, and patient cognitive status into account. The current study aims to report the rates of dislocations, revisions and other complications for primary cemented HA in patients with displaced FNF. MATERIALS AND METHODS: Single-center retrospective follow-up study of an unselected historic cohort. 743 consecutive hips (551 W and 192 M) at mean (SD) age of 83.6 (8.4) years received primary cemented HA for displaced FNF by posterolateral surgical approach between January 2012 and December 2019. Patient files and radiographs were evaluated for dislocations, revisions, and other complications until death or end of the follow-up period, and the educational level of the surgeon was noted. RESULTS: During a mean (SD) follow-up period of 2.7 (2.2) years, there were 6.1% (n = 45) dislocations, in which 82% (first dislocation) appeared within the first 30 postoperative days, and 51% (n = 23) of the dislocations requiring subsequent surgery. At the time of the last available follow-up, 57% (n = 421) of the patients were dead. A non-dislocation related revision was needed in 3.4% (n = 25) of the patients [in which infection accounted for 40% (n = 10) and traumatic periprosthetic fracture for 32% (n = 8)]. Thirty-day mortality was 9.2% and 1-year mortality 25.8%. There were no differences in patient's age, gender, or educational level of the surgeon between the dislocation and the no dislocation groups. Patients aged < 70 years presented with a higher dislocation rate (p < 0.001) than the patients aged > 70 years. CONCLUSION: Primary HA presents a safe and robust approach with acceptable complication rates in a genuine unselected cohort of displaced FNF, particularly for patients aged > 70.

Cutaneous anaesthesia of hip surgery incisions with iliohypogastric and subcostal nerve blockade: A randomised trial.

BACKGROUND: Cutaneous nerve blockade may improve analgesia after hip surgery. Anaesthesia after the lateral femoral cutaneous (LFC) nerve block is too distal for complete coverage of most hip surgery incisions, which requires additional anaesthesia of the adjacent, proximal area. The transversalis fascia plane (TFP) block potentially anaesthetises the iliohypogastric and subcostal nerves. The primary aim of the present study was to investigate, if the TFP block provides cutaneous anaesthesia adjacent to the LFC nerve block. METHODS: Active vs placebo TFP blocks were compared in a paired randomised controlled trial (RCT) in 20 volunteers, who all had bilateral LFC nerve blocks. The day preceding the RCT, the area anaesthetised by a novel selective ultrasound guided subcostal nerve block was identified bilaterally in order to assess the contribution of the subcostal nerve to the area anaesthesia by the TFP block. RESULTS: Anaesthesia of the lateral hip region after TFP block was 80%. The cutaneous anaesthesia after active TFP block was in continuity with the LFC nerve block in 65%. Combined TFP and LFC nerve blockade significantly increased the coverage of hip surgery incisions compared to LFC nerve block alone. The success rate of blocking the subcostal nerve was 50% with the TFP block. CONCLUSION: The TFP block anaesthetises the skin proximal to the LFC nerve block by anaesthetising the iliohypogastric and subcostal nerves. TFP block as a supplement to LFC nerve block improves the coverage of the proximal surgical incisions used for hip surgery.

Incorporation of raloxifene-impregnated allograft around orthopedic titanium implants impairs early fixation but improves new bone formation.

BACKGROUND: The anti-osteoporotic drug raloxifene reduces the risk of vertebral fractures by increasing bone mass density. We investigated whether raloxifene offers any benefits in augmenting early fixation of orthopedic implants in the setting of impaction bone grafting. METHODS: 24 non-weight-bearing grafted gap implants were inserted bilaterally into the tibia of 12 dogs. The 2.5-mm peri-implant gap was filled with either raloxifene-impregnated or untreated bone allograft. Implants were harvested after 28 days. Implant fixation was assessed by mechanical testing and histomorphometric evaluation. RESULTS: Raloxifene-treated allograft reduced early implant fixation compared to untreated allograft, as measured by inferior maximum shear strength (p < 0.001) and apparent shear stiffness (p = 0.001). We found that the raloxifene group had more newly formed bone in the gap around the implant (p = 0.02), but also less allograft (p = 0.03). INTERPRETATION: The accelerated allograft resorption in the raloxifene group explained the impaired early fixation, despite its stimulation of new bone formation. Our results with local and possible high-dose treatment are not consistent with current theory regarding the mechanism of how systemic raloxifene administration counteracts the decrease in BMD in postmenopausal women. Instead of being solely anti-resorptive as generally held, our results indicate a possible anabolic side of raloxifene.

Tension band versus locking plate fixation for patella fractures - a protocol of a randomised controlled trial.

INTRODUCTION: Following surgical management of patella fractures, patients commonly report pain; difficulties with weight-bearing tasks such as walking, running and climbing stairs; and restrictions in quality of life. Recently, a locking plate system for surgical management of patella fractures has been introduced. To date, no studies have compared standard treatment with tension band wiring with locking plate fixation in a randomised study design. We aim to compare the one-year patient-reported Knee Injury and Osteoarthritis Outcome subscale scores (KOOS5-subscales) after standard care tension band fixation with locking plate fixation for patients with patella fractures. METHODS: This is a multicentre randomised and prospective clinical trial. A total of 122 patients will be included in the study, and the primary outcome will be the KOOS subscales at 12 months after surgery. CONCLUSIONS: Findings from the present study are expected to advance our understanding of outcome following surgical treatment of patella fractures. FUNDING: This study is funded, in part, by the Novo Nordisk Foundation, Denmark. CLINICALTRIALS: gov ID: NCT04891549.

Rinsing of allograft bone does not improve implant fixation: a study in 12 dogs.

BACKGROUND AND PURPOSE: Impacted morselized allograft bone is a well-established method for reconstructing bone defects at revision surgery. However, the incorporation of bone graft is not always complete, and a substantial volume of fibrous tissue has been found around grafted implants. We hypothesized that rinsing the bone graft may improve graft incorporation by removing the majority of immunogenic factors present in blood, marrow, and fat. METHODS: We implanted a cylindrical (10- × 6-mm) porous-coated Ti implant into each proximal tibia of 12 dogs. The implants were surrounded by a 2.5-mm gap into which morselized fresh frozen allograft bone was impacted. The bone graft was either (1) untreated or (2) rinsed in 37°C saline for 3 × 1 min. After 4 weeks, the animals were killed and implant fixation was evaluated by mechanical push-out and histomorphometry. RESULTS: The groups (rinsed vs. control) were similar regarding mechanical implant fixation (mean (SD)): shear strength (MPa) 2.7 (1.0) vs. 2.9 (1.2), stiffness (MPa/mm) 15 (6.7) vs. 15 (5.6), and energy absorption (kJ/m(2)) 0.5 (0.2) vs. 0.6 (0.4), The same was evident for the new bone formation on the implant surface and around the implant: ongrowth (%) 6 vs. 7 and ingrowth (%) 9 vs. 9. Although not statistically significant, a 61% reduction in fibrous tissue ongrowth and 50% reduction in ingrowth were found in the rinsed group. INTERPRETATION: Within the limits of this experimental model, we did not detect any benefits of rinsing morselized allograft bone prior to impaction grafting.

The positive predictive value of ankle fracture diagnosis in the Danish National Patient Registry.

INTRODUCTION: Information on data validity is essential for understanding the precision of studies based on data from the Danish National Patient Registry (DNPR). Thus, the aim of this study was to validate the quality of ankle fracture data in the DNPR. METHODS: We identified all patients from four hospitals with a surgically treated ankle fracture between 1 January 2018 and 31 December 2018. The positive predictive value (PPV) was estimated for a random sample of 10% of patients with both a relevant ankle fracture diagnosis code and a relevant procedure code, as well as for patients with only a relevant ankle fracture diagnosis code or a relevant ankle fracture procedure code. We collected data from medical records and X-rays. Two consultants independently validated the ankle fracture diagnosis and procedure codes reported to the DNPR. RESULTS: Among the four centres, 651 patients were identified with both an ankle fracture diagnosis and a procedure code. Among these, data from 65 (10%) patients were extracted for validation. For these patients, the PPV for an ankle fracture was 0.95 (95% confidence interval (CI): 0.88-0.99). The PPV for the diagnosis code was 0.89 (95% CI: 0.79-0.95), and for the procedure code, the PPV was 0.82 (95% CI: 0.70-0.90). For patients with only an ankle fracture diagnosis code or only a surgical procedure code, the PPV for an ankle fracture was 0.77 (95% CI: 0.64-0.87). CONCLUSION: This study showed that ankle fracture diagnosis and procedure codes registered in the DNPR are of a high quality and thus constitute a valuable data source for research on ankle fractures. FUNDING: none. TRIAL REGISTRATION: The Danish Data Protection Agency approved the study (journal number 2015-18/62866).

[Safe surgical dislocation of the hip to treatment of injuries after traumatic hip injury in children].

Traumatic dislocation of the hip in children is rare. Immediately closed reduction is important but contains a risk of tissue becoming intertwined in the joint space, and a risk of development of avascular femoral head necrosis. In this case report, we present two cases of traumatic hip luxation in an 11-year-old boy and a nine-year-old boy, where intertwined labral tears were recognised immediately following closed reduction in one case and after two weeks in the other. They were treated with safe surgical dislocation of the femoral head. Blood flow to the femoral head was ensured by perioperative monitoring, and both boys had complete recovery.

Randomized trial of ultrasound-guided superior cluneal nerve block.

BACKGROUND AND OBJECTIVES: The superior cluneal nerves originate from the dorsal rami of primarily the upper lumbar spinal nerves. The nerves cross the iliac spine to innervate the skin and subcutaneous tissue over the gluteal region. The nerves extend as far as the greater trochanter and the area of innervation may overlap anterolaterally with the iliohypogastric and the lateral femoral cutaneous (LFC) nerves. A selective ultrasound-guided nerve block technique of the superior cluneal nerves does not exist. A reliable nerve block technique may have application in the management of postoperative pain after hip surgery as well as other clinical conditions, for example, chronic lower back pain. In the present study, the primary aim was to describe a novel ultrasound-guided superior cluneal nerve block technique and to map the area of cutaneous anesthesia and its coverage of the hip surgery incisions. METHODS: The study was carried out as two separate investigations. First, dissection of 12 cadaver sides was conducted in order to test a novel superior cluneal nerve block technique. Second, this nerve block technique was applied in a randomized trial of 20 healthy volunteers. Initially, the LFC, the subcostal and the iliohypogastric nerves were blocked bilaterally. A transversalis fascia plane (TFP) block technique was used to block the iliohypogastric nerve. Subsequently, randomized, blinded superior cluneal nerve blocks were conducted with active block on one side and placebo block contralaterally. RESULTS: Successful anesthesia after the superior cluneal nerve block was achieved in 18 of 20 active sides (90%). The area of anesthesia after all successful superior cluneal nerve blocks was adjacent and posterior to the area anesthetized by the combined TFP and subcostal nerve blocks. The addition of the superior cluneal nerve block significantly increased the anesthetic coverage of the various types of hip surgery incisions. CONCLUSION: The novel ultrasound-guided nerve block technique reliably anesthetizes the superior cluneal nerves. It anesthetizes the skin posterior to the area innervated by the iliohypogastric and subcostal nerves. It improves the anesthetic coverage of incisions used for hip surgery. Among potential indications, this new nerve block may improve postoperative analgesia after hip surgery and may be useful as a diagnostic block for various chronic pain conditions. Clinical trials are mandated. TRIAL REGISTRATION NUMBER: EudraCT, 2016-004541-82.

Bosworth fracture dislocation of the ankle: - Two case reports with perioperative illustration.

The Bosworth fracture dislocation of the ankle is rare and present difficulties in treatment if not immediately recognized. Here we present two cases with pre- and postoperative x-rays and perioperative image of the dislocation. The fracture dislocations were further complicated by talocrural dislocations and were treated with open reduction and internal fixation.

The Lateral Femoral Cutaneous Nerve: Description of the Sensory Territory and a Novel Ultrasound-Guided Nerve Block Technique.

BACKGROUND AND OBJECTIVES: Nerve blockade of the lateral femoral cutaneous (LFC) nerve provides some analgesia after hip surgery. However, knowledge is lacking about the extent of the cutaneous area anesthetized by established LFC nerve block techniques, as well as the success rate of anesthetic coverage of various surgical incisions. Nerve block techniques that rely on ultrasonographic identification of the LFC nerve distal to the inguinal ligament can be technically challenging. Furthermore, the branching of the LFC nerve is variable, and it is unknown if proximal LFC nerve branches are anesthetized using the current techniques. The primary aim of this study was to investigate a novel ultrasound-guided LFC nerve block technique based on injection into the fat-filled flat tunnel (FFFT), which is a duplicature of the fascia lata between the sartorius and the tensor fasciae latae muscle, in order to assess the success rate of anesthetizing the proximal LFC nerve branches and covering of the different surgical incisions used for hip surgery. METHODS: First, a cadaveric study was conducted in order to identify an FFFT injection technique that would provide adequate injectate spread to the proximal LFC nerve branches. Second, a clinical study was conducted in a group of 20 healthy volunteers over 2 consecutive days. On trial day 1, successful complete anesthesia of the LFC nerve was defined by performing a suprainguinal fascia iliaca block bilaterally in each subject. On trial day 2, a triple-blind randomized controlled trial compared the effect of the novel ultrasound-guided LFC nerve block technique for bupivacaine versus placebo. The primary end point was the success rate of anesthesia of the proximal cutaneous area innervated by the LFC nerve for the FFFT injection with bupivacaine versus placebo. RESULTS: Adequate spread of injectate to the proximal LFC nerve branches in cadavers was obtained by injecting 10 mL with dynamic needle-tip tracking in the FFFT. Application of this technique in the randomized controlled trial provided anesthesia of the lateral thigh with a success rate of 95% (95% confidence interval, 73.9%-99.8%) for the active side and 0% for placebo (P < 0.001). The proximal branches were anesthetized with a success rate of 68% (95% confidence interval, 43.4%-87.4%) on the active side. The proximal extent of the anesthetized cutaneous area was on average 7.9 cm distal to the greater trochanter. CONCLUSIONS: This novel LFC nerve block technique is easy and quick and reliably produces anesthesia of the lateral thigh. The greater trochanter is rarely included in the area of anesthesia, which reduces the coverage of each specific surgical incision. The success rate of 68% in anesthetizing the proximal nerve branches must be further evaluated by future research.

Reduced need for extraperitoneal pelvic packing for severe pelvic fractures is associated with improved resuscitation strategies.

BACKGROUND: Extraperitoneal pelvic packing (EPP) was introduced at Oslo University Hospital Ulleval (OUHU) in 1994. Published studies from other institutions have advocated its application as a first-line therapy in lieu of angiography. Extraperitoneal pelvic packing is invasive with a high risk of complications, and its role remains an issue of discussion. In line with international trends, an updated massive hemorrhage protocol was implemented at OUHU in 2007. We hypothesized a decreased need for EPP owing to the major changes in resuscitation strategies. METHODS: Retrospective analysis of data from the OUH Trauma Registry and patient charts for the period 2002-2012 was performed. All pelvic fractures with Abbreviated Injury Severity (AIS) score of 3 or higher and/or transfused during the period before intensive care unit admission regardless of the pelvic AIS were included. The population was analyzed for trends and differences between 2002-2006 (P1) and 2007-2012 (P2). Further analysis was performed on the group of patients transfused five or more units of red blood cells (RBCs). RESULTS: We included 648 patients (P1, 297; P2, 351). There was no difference in median injury severity score, pelvic AIS, or age between the two periods. Median base deficit on admission was higher in P2 (4.2 vs 3.3 mmol/L; p < 0.01). The EPP rate decreased from P1 to P2 (17-10%; p < 0.01). A similar reduction in the angiography rate (15% vs 9%; p < 0.01) was observed, with a concomitant decrease in hemorrhage-related deaths (10% vs 5%; p = 0.01). The subgroup analysis of patients transfused five or more units of RBCs revealed significant increase in the use of plasma and platelets in P2. Multiple logistic regression models for the subgroup transfused five or more units of RBCs confirm the change in resuscitation strategy to be significantly associated with reduced EPP, and identifying admission in P2 to be associated with a 63% decreased odds ratio for EPP. CONCLUSIONS: The EPP and angiography rates for exsanguinating pelvic injuries have decreased with improved resuscitation strategies, reducing RBC requirements and hemorrhage-related deaths. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Bone allograft and implant fixation tested under influence of bio-burden reduction, periosteal augmentation and topical antibiotics. Animal experimental studies.

Loosening of an artificial joint prosthesis is a painful and debilitating condition that can be treated only by re-operation. Re-operations accounted for approximately 15% of all hip replacement operations performed in Denmark between the year 1995 and 2010. The process of loosening is often accompanied by destructive inflammation and osteolysis, which leads to insufficient bone stock that often requires extensive bone grafting. Impacted morselized bone graft is a well-established method for improving the amount and quality of bone stock that ensures sufficient stability and anchorage of the revision implants. Among bone graft options, the autologous bone graft is considered the gold standard. It is naturally biocompatible, but its use in revision surgery is curtailed by its limited volume and by considerable donor site morbidity. Allograft bone is readily available and is the most commonly used graft material. However, it has been shown that the incorporation of allograft bone into the host bone is not always complete, and substantial fibrous tissue formation has been described. A reason for this may be that allograft bone is a foreign tissue, which, contrary to autogenic bone, may induce an immunogenic response that leads to increased fibrous tissue formation. Furthermore, the fresh-frozen allograft has minimal osteoinductive and no osteogenic capacity. The studies in this thesis have investigated ways of improving the incorporation of allograft bone by adding osteoinductive cells from the periosteum and reducing the immunogenic load of the allograft bone by rinsing. Furthermore, the impact of antibiotic protection of the bone graft has been evaluated. The same experimental implant model was used in all three studies. This model enables evaluation of early implant fixation and osseointegration of an uncemented implant surrounded by impacted morselized bone graft. Unloaded gap implants were inserted into the metaphysis of the proximal tibia (Study I) and distal femur (Study II and III) in dogs. The observation period was four weeks and the bone-implant specimens were evaluated by mechanical tests and histomorphometry. Study I compared the fixation of grafted implants where the morselized allograft bone was either rinsed in saline or not. Since the majority of immunogenic factors in allograft bone are present in the blood, the marrow and fat, the objective of this study was to investigate whether rinsing of the allograft bone would lower the immunogenic load and thereby improve osseointegration and bone graft incorporation. We found no statistically significant difference in the histomorphometric or the mechanical evaluations between the two groups. Study II investigated the addition of minced periosteal tissue to the allograft bone. The objective of this study was to investigate whether adding autologous tissue containing bone-forming cells could augment the bioactivity of allograft bone and thereby improve bone graft incorporation. Contrary to our hypothesis, we found no benefit of adding autologous periosteum to the allograft bone. No differences in mechanical fixation were observed, and the periosteum-treated implants had reduced new-bone ongrowth and increased amounts of fibrous tissue. Study III evaluated the impact of antibiotic impregnation of the allograft bone prior to impaction. Antibiotic-impregnated bone graft has been used in one-stage septic revisions and in cases where potential infection is suspected, but its potentially harmful effect on bone graft incorporation has not been studied. The aim of this study was to evaluate the impact of Tobramycin impregnation of bone-grafted implants by mechanical testing and histomorphometric assessment. We hypothesized that Tobramycin impregnation would impair implant fixation. Under the conditions of the present study, Tobramycin impregnation of allograft bone did not appear to impair implant fixation or tissue in-growth. In conclusion, under the premises of the present studies, no benefits of periosteal augmentation or rinsing of the bone graft prior to impaction were found. Antibiotic impregnation seems safe in terms of osseointegration, but surgeons should weigh the potentially cytotoxic effect of Tobramycin against its beneficial anti-microbial effect in joint arthroplasty revisions until further basic data on toxicity are available.

Does tobramycin impregnation of allograft bone affect implant fixation? - an experimental study in 12 dogs.

Clinical trials have used antibiotic impregnated impacted bone allograft in revisions of infected arthroplasties. By this method high local antibiotic concentration and good control of infection was achieved. Toxicity studies, however, suggest that high local antibiotic concentration can impair osteoblast replication. We therefore asked whether impregnating morselized allograft bone with different quantities of tobramycin before impaction would impair implant fixation. We implanted three cylindrical (10 mm × 6 mm) porous-coated titanium implants into the distal femurs of 12 dogs. The implants were surrounded by a circumferential gap of 2.5 mm into which a standardized volume of morselized allograft bone, with or without tobramycin, was impacted. In each animal, the bone graft was impregnated with either 0 mg (control), 50 mg (low dose), or 200 mg (high dose) of tobramycin per 1 mL of bone graft. At the end of the 4 weeks experimental period, the implants with surrounding bone were evaluated by histomorphometric analysis and mechanical push-out test. We found no difference between the treatment groups regarding new bone formation, bone graft resorption, or implant fixation. There was, however, a tendency toward a decrease in implant fixation with higher tobramycin dose. The present study is unable to provide evidence on whether the use of topical tobramycin with allograft is safe or whether it indeed can impair implant fixation. The tendency toward an impaired implant fixation warrants further preclinical studies. Its current clinical use should be weighed against its possible positive effects on preventing infection in complicated revisions.

Periosteal augmentation of allograft bone and its effect on implant fixation - an experimental study on 12 dogs().

PURPOSE: Periosteum provides essential cellular and biological components necessary for fracture healing and bone repair. We hypothesized that augmenting allograft bone by adding fragmented autologous periosteum would improve fixation of grafted implants. METHODS: In each of twelve dogs, we implanted two unloaded cylindrical (10 mm x 6 mm) titanium implants into the distal femur. The implants were surrounded by a 2.5-mm gap into which morselized allograft bone with or without addition of fragmented autologous periosteum was impacted. After four weeks, the animals were euthanized and the implants were evaluated by histomorphometric analysis and mechanical push-out test. RESULTS: Although less new bone was found on the implant surface and increased volume of fibrous tissue was present in the gap around the implant, no difference was found between treatment groups regarding the mechanical parameters. Increased new bone formation was observed in the immediate vicinity of the periosteum fragments within the bone graft. CONCLUSION: The method for periosteal augmentation used in this study did not alter the mechanical fixation although osseointegration was impaired. The observed activity of new bone formation at the boundary of the periosteum fragments may indicate maintained bone stimulating properties of the transplanted cambium layer. Augmenting the bone graft by smaller fragments of periosteum, isolated cambium layer tissue or cultured periosteal cells could be studied in the future.

Preclinical evaluation of zoledronate to maintain bone allograft and improve implant fixation in revision joint replacement.

BACKGROUND: Revision arthroplasty surgery is often complicated by loss of bone stock that can be managed by the use of bone allograft. The allograft provides immediate stability for the revision implant but may be resorbed, impairing subsequent implant stability. Bisphosphonates can delay allograft resorption. We hypothesized that zoledronate-impregnated allograft impacted around revision implants would improve implant fixation as characterized by mechanical push-out testing and histomorphometry. METHODS: Twenty-four axially pistoning micromotion devices were inserted bilaterally into the knees of twelve dogs according to our revision protocol. This produced a standardized revision cavity with a loose implant, fibrous tissue, and a sclerotic bone rim. Revision surgery was performed eight weeks later; after stable titanium revision components were implanted, saline solution-soaked allograft was impacted around the component on the control side and allograft soaked in 0.005 mg/mL zoledronate was impacted on the intervention side. The results were evaluated after four weeks. RESULTS: The zoledronate treatment resulted in a 30% increase in ultimate shear strength (p = 0.023), a 54% increase in apparent shear stiffness (p = 0.002), and a 12% increase in total energy absorption (p = 0.444). The quantity of allograft in the gap was three times greater in the zoledronate group compared with the control group (p < 0.001). The volume fraction of new bone in the zoledronate group (25%; 95% confidence interval [CI], 22% to 28%) was similar to that in the control group (23%; 95% CI, 19% to 26%) (p = 0.311). CONCLUSIONS: The data obtained in this canine model suggest that pretreating allograft with zoledronate may be beneficial for early stability of grafted revision arthroplasty implants, without any adverse effect on bone formation. Clinical studies are warranted. CLINICAL RELEVANCE: The zoledronate treatment is simple to apply in the clinical setting. The treatment could increase early stability of revision joint replacements without impairing new bone formation. In the long term, this can potentially improve the longevity of revision joint replacements and reduce the number of subsequent revisions.