Complications of antibiotic cement spacers used for elbow infections.

BACKGROUND: Antibiotic cement spacers have been widely used in the treatment of joint infections. There are no commercially available antibiotic spacers for the elbow. Instead, they are typically fashioned by the surgeon at the time of surgery using cement alone or a combination of cement with sutures, Steinmann pins, external fixator components, or elbow arthroplasty components. There is no consensus regarding the ideal elbow antibiotic spacer and no previous studies have examined the complications associated with these handmade implants in relation to their unique structural design. METHODS: We retrospectively reviewed 55 patients who had 78 static antibiotic cement spacers implanted between January 1998 and February 2021 as part of a 2-stage treatment plan for infection of an elbow arthroplasty, other elbow surgery, or primary elbow infection. Several antibiotic spacer structures were used during the study period. For analysis purposes, the spacers were classified into linked and unlinked spacers based on whether there was a linking mechanism between the humerus and the ulna. Complications related to these spacers that occurred either during the implantation, between implantation and removal, or during removal were recorded and analyzed from chart review and follow-up x rays. Reoperations due to spacer-related complications were also recorded. RESULTS: Among the 55 patients (78 spacers), there were 23 complications, including 17 minor and 6 major complications. The most common complication of unlinked spacers (intramedullary [IM] dowels, beads and cap spacer) was spacer displacement. Other complications included IM dowel fracture and difficulty locating beads during spacer removal. The major complications of linked cement spacers included two periprosthetic humerus fractures after internal external fixator cement spacers and re-operation due to breakage and displacement of one bushing cement spacer. The major complications of unlinked cement spacers included two reoperations due to IM dowel displacement and one reoperation due to displacement of beads. Among patients who had removal of all components and those with native joints, there was no statistically significant difference between internal external fixator cement spacers and unlinked cement spacers in minor complication rates (30% vs. 16%, P = .16), major complication rates (7% vs. 8%, P = .85) and reoperation rates (0% vs. 8%, P = .12). CONCLUSIONS: Static handmade antibiotic elbow spacers have unique complications related to their structural designs. The most common complication of linked and nonlinked cement spacers were failure of the linking mechanism and displacement, respectively. Surgeons should keep in mind the possible complications of different structures of cement spacers when choosing 1 antibiotic spacer structure over another.

Cement-within-cement technique in revision reverse shoulder arthroplasty.

BACKGROUND: The purpose of this study was to determine the complications and results of cement-within cement-humeral fixation in revision reverse shoulder arthroplasty. METHODS: In 38 shoulders, a cemented humeral component was revised to a cemented reverse humeral component using a cement-within-cement technique. The mean follow-up time was 3.7 (2.0-7.0) years. Clinical, radiologic, and hard outcomes were assessed using the Kaplan-Meier survival method, Fisher exact test, and Student t-test. RESULTS: The average operative time for the cement-within-cement technique was 153 minutes. There were 7 (18%) nondisplaced intraoperative fractures involving the greater tuberosity that occurred on implant removal; all healed at last follow-up. A second revision surgery was performed in 3 (8%) patients who underwent cement-in-cement humeral component revision for glenoid loosening (n = 1), periprosthetic instability associated with glenoid loosening (n = 1), and periprosthetic humerus fracture (n = 1). The overall implant revision-free survival at 2 and 5 years was 95% and 91%, respectively. Patients experienced significant pain relief, improvements in their shoulder range of motion, and high satisfaction. There was 1 "at-risk" humeral component (grade 4 or higher humeral lucency, moderate subsidence) that did not undergo revision surgery. There were 2 other humeral components with grade 3 humeral lucency, no subsidence. CONCLUSIONS: Cement-within-cement fixation of the humeral component in revision reverse shoulder arthroplasty is associated with a reasonable operative time, good medium-term survival rates, and good pain relief and functional outcomes with low complications. This technique is an important consideration to preserve humeral bone stock and potentially humeral component and implant stability.

The Mark Coventry Award: Trabecular metal tibial components were durable and reliable in primary total knee arthroplasty: a randomized clinical trial.

BACKGROUND: Although highly porous metals have demonstrated excellent bone ingrowth properties and so are an intriguing option for fixation in total knee arthroplasty (TKA), some surgeons are skeptical about the durability of uncemented tibial fixation and the potential for soft tissues to adhere to these porous metals and perhaps cause knee stiffness or pain. QUESTIONS/PURPOSES: The purpose of this study was to compare, in the context of a randomized clinical trial, a highly porous metal tibia compared with a traditional modular cemented tibia in terms of survivorship, Knee Society scores, range of motion (ROM), and complications. METHODS: From 2003 to 2006, 397 patients (age 67.8 ± 8.7 years; 54% female) were randomized to three groups: (1) traditional modular cemented tibia; (2) cemented highly porous metal tibia; and (3) uncemented highly porous metal tibia. The same posterior-stabilized femoral component and patella component were cemented in every case. Stratified randomization was done for surgeon, patient's age, sex, and body mass index. Survivorship at 5 years was compared between the groups, as were Knee Society scores, ROM, and complications. Radiographic assessment included alignment, radiolucency, and implant migration/loosening. Patients were followed until death, revision, or for a minimum of 2 years (mean, 5 years; range, 2-9 years). Four patients were lost to followup before 2 years. RESULTS: Highly porous metal tibias (both uncemented and cemented) were no different from traditional cemented modular tibial modular components in terms of survivorship at 5 years using a intention-to-treat analysis (96.8% [1]; 97.6% [2]; 96.7% [3]; p = 0.59). A per-protocol analysis revealed that no highly porous metal tibia was revised for aseptic loosening. Highly porous metal tibias performed comparably to traditional cemented modular tibias in terms of Knee Society scores, ROM, and the frequency of complications. CONCLUSIONS: At 5 years this randomized clinical trial demonstrated that highly porous metal tibias provided comparably durable fixation and reliable pain relief and restoration of function when compared with a traditional cemented modular tibia in TKA. LEVEL OF EVIDENCE: Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Radiological humeral adaptative changes five years after anatomical total shoulder arthroplasty using a standard-length cementless hydroxyapatite-coated humeral component.

AIMS: The purpose of this study was to report bone adaptive changes after anatomical total shoulder arthroplasty (TSA) using a standard-length hydroxyapatite (HA)-coated humeral component, and to report on a computer-based analysis of radiographs to determine changes in peri-implant bone density objectively. METHODS: A total of 44 TSAs, performed between 2011 and 2014 using a cementless standard-length humeral component proximally coated with HA, were included. There were 23 males and 21 females with a mean age of 65 years (17 to 65). All shoulders had good quality radiographs at six weeks and five years postoperatively. Three observers graded bone adaptive changes. All radiographs were uploaded into a commercially available photographic software program. The grey value density of humeral radiological areas was corrected to the grey value density of the humeral component and compared over time. RESULTS: Stress shielding was graded as mild in 14 shoulders and moderate in three; the greater tuberosity was the predominant site for stress shielding. The mean metaphyseal and diaphyseal fill-fit ratios were 0.56 (SD 0.1) and 0.5 (SD 0.07), respectively. For shoulders with no radiologically visible stress shielding, the mean decrease in grey value in zones 1 and 7 was 20%, compared with 38% in shoulders with radiologically visible stress shielding. CONCLUSION: The rate of moderate stress shielding was 7%, five years after implantation of a cementless standard-length HA-coated humeral component. Clinical observation of stress shielding identified on radiographs seems to represent a decrease in grey value of 25% or more. Cite this article: Bone Joint J 2021;103-B(5):958-963.

Survivorship of the humeral component in shoulder arthroplasty.

BACKGROUND: Loosening of the humeral component is rarely a cause for revision. This study was conducted to determine long-term survivorship of humeral components and investigate the risk factors associated with humeral component removal or revision. MATERIALS AND METHODS: From 1984 to 2004, 1423 patients underwent 1584 primary Neer and Cofield shoulder arthroplasties. The Kaplan-Meier method was used to estimate implant survival. Cox proportional hazards regression was used to assess the effects of age, gender, etiology of the disease, surgery type (hemi vs total), fixation (cemented vs noncemented), and the humeral component design (Neer II, Cofield 1 or 2) with survival free of revision or removal of the humeral component. RESULTS: There were 108 revisions and 17 removals of the humeral component. Estimates of survivorship free of revision or removal of the humeral component for any reason was 94.8% (95% confidence interval [CI], 93.6-96.0) at 5 years, 92.0% (95% CI, 90.4-93.6) at 10 years, 86.7% (95% CI, 84.2-89.4) at 15 years, and 82.8% (95% CI, 78.5-87.5) at 20 years. Younger age, male gender, replacement due to posttraumatic arthritis, an uncemented component, and use of a metal-backed glenoid component increased the likelihood of humeral component failure. CONCLUSIONS: The need for revision of the humeral component is commonly related to glenoid or glenoid component issues. Patient and diagnostic factors play a role in implant survival; implant type and method of fixation are less important. LEVEL OF EVIDENCE: Level 4; Case series, treatment study.

Midterm to long-term followup of staged reimplantation for infected hip arthroplasty.

UNLABELLED: Most reports on two-stage reimplantation have focused on the short-term cure rate of infection, but little is known about long-term reinfection-free survival or mechanical durability. We retrospectively reviewed 168 patients (169 hips) with infected arthroplasty, all of whom had two-stage reimplantation for the treatment of an infected total hip arthroplasty between 1988 and 1998. In the second stage, the femoral component was fixed with antibiotic-loaded bone cement in 121 hips; the remaining femoral components and all acetabular components were uncemented. The minimum followup time was 2 years (mean, 7 years; range, 2-16 years). At most recent followup, 12 hips (7.1%) were reoperated on for reinfection and 13 hips (7.7%) were revised for aseptic loosening or osteolysis. Apparently aseptic loosening occurred on one or both sides of the joint in 24 hips (14.2%). The 10-year survivals free of reinfection and mechanical failure were 87.5% and 75.2% respectively. Nineteen hips dislocated and eight underwent revision surgery for instability. The method of femoral component fixation, either with or without cement, did not correlate with risk of infection, loosening, or mechanical failure. Based on these results, the method of fixation used for the femoral component during two-stage reimplantation surgery should be based on the surgeon's preference for fixation combined with the assessment of femoral bone stock. LEVEL OF EVIDENCE: Level IV, case series. See the Guidelines for Authors for a complete description of levels of evidence.

Outcomes of Uncemented Versus Cemented Reverse Shoulder Arthroplasty for Proximal Humerus Fractures.

Reverse shoulder arthroplasty (RSA) for proximal humerus fractures (PHFs) is traditionally performed with cemented humeral fixation. The purpose of this study was to compare the clinical and radiographic outcomes of cemented and cementless RSA for PHF. Between 2010 and 2014, 38 acute PHFs were treated with RSA and followed for a minimum of 2 years (mean, 37 months; range, 24-66 months). The mean time from fracture to RSA was 7 days (range, 1-30 days). Humeral stems were cemented in 19 shoulders and uncemented in 19 shoulders. Outcome measures included visual analog scale pain scores, range of motion, postoperative Quick Disabilities of the Arm, Shoulder and Hand scores, American Shoulder and Elbow Surgeons scores, and radiographic parameters. The 2 groups had similar visual analog scale pain scores, postoperative range of motion, and Quick Disabilities of the Arm, Shoulder and Hand scores (P>.05). American Shoulder and Elbow Surgeons scores and satisfaction scores were significantly higher with cemented humeral fixation (76.3 vs 48.0, P=.005; 1.2 vs 1.8, P=.04). Radiographically, there was no difference in terms of tuberosity healing, component loosening, or notching (P>.05). Reverse shoulder arthroplasty provides pain relief for PHF, regardless of humeral fixation. In this cohort, cementless fixation was associated with worse patient-reported outcomes, although no correlation could be established with pain, motion, or tuberosity healing. Further studies are required before cementless fixation can be recommended for RSA for fracture. [Orthopedics. 2019; 42(2):e236-e241.].

Joint contracture is reduced by intra-articular implantation of rosiglitazone-loaded hydrogels in a rabbit model of arthrofibrosis.

Trauma, surgery, and other inflammatory conditions can lead to debilitating joint contractures. Adjunct pharmacologic modalities may permit clinical prevention and treatment of recalcitrant joint contractures. We investigated the therapeutic potential of rosiglitazone by intra-articular delivery via oligo[poly(ethylene glycol)fumarate] (OPF) hydrogels in an established rabbit model of arthrofibrosis. OPF hydrogels loaded with rosiglitazone were characterized for drug elution properties upon soaking in minimum essential media (MEM) with 10% fetal bovine serum and measurements of drug concentrations via High Performance Liquid Chromatography (HPLC). Drug-loaded scaffolds were surgically implanted into 24 skeletally mature female New Zealand White rabbits that were divided into equal groups receiving OPF hydrogels loaded with rosiglitazone (1.67 mg), or vehicle control (10 µl DMSO). After 8 weeks of joint immobilization, rabbits were allowed unrestricted cage activity for 16 weeks. Contracture angles of rabbit limbs treated with rosiglitazone showed statistically significant improvements in flexion compared to control animals (mean angles, respectively, 64.4° vs. 53.3°, p < 0.03). At time of sacrifice (week 24), animals in the rosiglitazone group continued to exhibit less joint contracture than controls (119.0° vs. 99.5°, p = 0.014). The intra-articular delivery of rosiglitazone using implanted OPF hydrogels decreases flexion contractures in a rabbit model of arthrofibrosis without causing adverse effects (e.g., gross inflammation or arthritis). Statement of Clinical Significance: Post-traumatic joint contractures are common and debilitating, with limited available treatment options. Pharmacologic interventions can potentially prevent and treat such contractures. This study is translational in that a commercially approved medication has been repurposed through a novel delivery device. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2949-2955, 2018.

Safety of Intra-Articular Implantation of Oligo[Poly(ethylene glycol) Fumarate] Scaffolds into the Rabbit Knee.

Implantable biomaterials supporting extended release of pharmacologic agents may permit localized intra-articular delivery of drugs that modulate the fibrotic response to injuries and surgery. Oligo[poly (ethylene glycol)] fumarate (OPF) is an attractive organic carrier, but its safety profile within synovial joints remains unclear. Here, we assessed the safety of OPF sponges using a validated in vivo model of knee arthrofibrosis. A cohort of 102 rabbits was divided into five groups: arthrotomy only (24), arthrotomy with OPF scaffold placement (24), surgically induced contracture (24), surgically induced contracture with OPF scaffold placement (24), and control without any surgical intervention (6). Six rabbits per surgical group were sacrificed at 72 h, 2, 8, and 24 weeks. Outcomes included biomechanical testing of range of motion, histologic analysis of synovial and cartilage tissues, and scaffold degradation. Cartilage histology and biomechanical measurements were comparable between groups with and without OPF. Synovial inflammation scores were similar among most groups with a minimally elevated score in the rabbits with arthrotomy and OPF versus those with arthrotomy alone. Scores for synovial tissues in rabbits with contracture and OPF were clinically equivalent to those with contractures alone. Most animals (92%) retained scaffold fragments at 24 weeks. Thus, OPF scaffolds implanted into native or arthrofibrotic rabbit knees neither induce nor aggravate cartilage damage, synovial inflammation, or contractures. The apparent safety of OPF scaffolds suggests that they are suitable carriers for the controlled delivery of reagents into the intra-articular joint space to treat arthrofibrosis.

Long-term results of use of a collared matte-finished femoral component fixed with second-generation cementing techniques. A fifteen-year-median follow-up study.

BACKGROUND: So-called second-generation cementing techniques in total hip arthroplasty have been shown to provide better survival of the femoral component than first-generation methods do; however, surface finish and other features of the component design also influence the durability of the reconstruction. The purpose of this study was to determine the results of primary total hip replacement with use of a collared femoral component with a matte-finished surface fixed with second-generation cementing techniques and followed for ten to twenty years. METHODS: The study group consisted of 256 consecutive hips in 236 patients who had had a primary total hip arthroplasty with fixation of a Harris Design-2 femoral component with second-generation cementing techniques (use of an intramedullary plug and a cement gun). The mean age of the patients at the time of the operation was sixty-six years. One hundred and twelve patients were male, and 124 were female. Seven patients were lost to follow-up less than ten years after the operation. The median duration of follow-up of the living patients who had not had a revision was 15.4 years. RESULTS: At the time of the most recent follow-up, nineteen femoral components (7%) had been revised because of aseptic loosening, five (2%) had been removed because of deep infection, and one (0.4%) had been revised because of recurrent dislocation. The mean Harris hip score for the surviving patients who had not had a revision improved from 51 points preoperatively to 91 points at the most recent evaluation. At fifteen years, the estimated survival rate of the femoral components was 92.2% with revision due to aseptic loosening as the end point and 90.1% with mechanical failure (radiographic loosening or revision due to aseptic loosening) as the end point. Patients who were younger than fifty years old at the time of the operation had a lower fifteen-year rate of survival of the femoral implant, in terms of both revision due to aseptic loosening (72.3% compared with 95.7%, p = 0.0001) and mechanical failure (72.3% compared with 93.1%, p = 0.005), than did patients who were fifty years or older. CONCLUSIONS: Fixation of this collared matte-finished femoral component with use of second-generation cementing techniques for primary total hip replacement provided satisfactory results at ten to twenty years in older patients but less satisfactory results in younger patients.

Surgical treatment of developmental dysplasia of the hip in adults: II. Arthroplasty options.

Total hip arthroplasty is the procedure of choice for most patients with symptomatic end-stage coxarthrosis secondary to hip dysplasia. The anatomic abnormalities associated with the dysplastic hip increase the complexity of hip arthroplasty. When pelvic bone stock allows, it is desirable to reconstruct the socket at or near the normal anatomic acetabular location. To obtain sufficient bony coverage of the acetabular component, the socket can be medialized or elevated, or a lateral bone graft can be applied. Uncemented acetabular components allow biologic fixation with potentially improved results compared with cemented cups, especially in young patients. The location of the acetabular reconstruction and the desired leg length influence the type of femoral reconstruction. Cemented and uncemented implants can be used in femoral reconstruction, depending on the clinical situation. Femoral shortening is required in some cases and can be performed by metaphyseal resection with a greater trochanteric osteotomy and advancement or by a shortening subtrochanteric osteotomy. The results of total hip arthroplasty demonstrate a high rate of pain relief and functional improvement. The long-term durability of cemented total hip arthroplasty reconstruction in these patients is inferior to that in the general population. The results of uncemented implants are promising, but only limited early and midterm data are available.

Comparison of wear and osteolysis in hip replacement using two different coatings of the femoral stem.

We compared the clinical and radiographic results of two matched series of total hip arthroplasties, one with hydroxyapatite-coated femoral stems, the other with a similar but porous-coated femoral stem. The prevalence of radiographic osteolysis was 16% in hips with hydroxyapatite-coated stems and 43% in hips with porous-coated femoral stems. In hips with hydroxyapatite-coated stems, osteolysis was always limited to Gruen zones 1 and 7. In contrast, distal osteolysis was present around 26% of the porous-coated stems. At 7 years, the survival-free rate of distal osteolysis was 100% in hips with hydroxyapatite-coated stems but 90% in hips with porous-coated stems (p=0.04). Circumferential hydroxyapatite coating of the femoral component reduced the occurrence of osteolysis and eliminated distal osteolysis at 5-10 years of follow-up. In addition, hydroxyapatite coating did not alter the wear rate.