Is Cementless Total Knee Arthroplasty Safe in Women Over 75 Y of Age?

BACKGROUND: Cementless total knee arthroplasty (TKA) is the subject of renewed interest. Previous concerns about survivorship have been addressed and there is an appeal in terms of biological fixation and surgical efficiency. However, even surgeon advocates have concerns about the risk of marked subsidence when using this technology in older patients at risk for osteoporosis. METHODS: This was a retrospective analysis of 1,000 consecutive fully cementless mobile bearing TKAs performed at a single institution on women over 75 years of age who had postoperative and 1-year x-rays. The primary outcome was the incidence of subsidence. RESULTS: There were three asymptomatic cases with definite subsidence and change in alignment. In a fourth symptomatic case, the femoral component subsided into varus and the tibia into valgus, thus maintaining alignment which facilitated nonoperative treatment in a 92-year-old. Overall, at 1 year, there were two- liner revisions for infection without recurrence. Five patients had further surgery, of which three were washouts and two were for periprosthetic fractures sustained postoperatively within 1 year. Seven patients had further anesthesia, of which five were manipulations and two were nonrecurrent closed reductions for spinouts. CONCLUSION: Cementless TKA did not have a high risk of subsidence in this at-risk population. In the hands of experienced surgeons, these procedures can be used safely irrespective of bone quality.

Using a ring to locate femoral head centre in total hip arthroplasty.

AIMS: Traditional methods of determining femoral head centre (FHC) during total hip arthroplasty (THA) rely on measuring the distance from a fixed point on the femur or using a calliper. The aim of this experiment was to investigate how accurately a simple circular ring could locate FHC. METHODS: 144 consecutively available femoral heads (FHs) were collected from patients undergoing THA. Each FH was orientated and mounted on a Sawbone, to create a model of its position on a proximal femur. The ring was applied to the posterior aspect of the FH and a head-centre pin (HCP) was then drilled into the FH and the ring removed, leaving the HCP in place.Each FH was then photographed normal to the axis of the HCP. A MATLAB analysis program then assessed the accuracy of the ring in locating FHC. RESULTS: Mean location accuracy for FHC was 1.77 (range 0.07-5.83) mm with 97.2% within 4 mm and all but 1 within 5 mm. CONCLUSIONS: This ring device located FHC to within 4 mm in 97% of a series of osteoarthritic FHs. This indicates that the posterior aspect of the FH maintains its sphericity late into the osteoarthritic process. Having a simple FHC location device during THA would be of value to control leg length and offset when using the posterior approach.

Are patient-reported outcomes the same following second-side surgery in primary hip and knee arthroplasty?

AIMS: Up to one in five patients undergoing primary total hip (THA) and knee arthroplasty (TKA) require contralateral surgery. This is frequently performed as a staged procedure. This study aimed to determine if outcomes, as determined by the Oxford Hip Score (OHS) and Knee Score (OKS) differed following second-side surgery. METHODS: Over a five-year period all patients who underwent staged bilateral primary THA or TKA utilizing the same type of implants were studied. Eligible patients had both preoperative and one year Oxford scores and had their second procedure completed within a mean (2 SDs) of the primary surgery. Patient demographics, radiographs, and OHS and OKS were analyzed. RESULTS: A total of 236 patients met the inclusion criteria, of which 122 were THAs and 114 TKAs. The mean age was 66.5 years (SD 9.4), with a 2:1 female:male ratio. THAs showed similar significant improvements in outcomes following first- and second-side surgery, regardless of sex. In contrast for TKAs, although male patients demonstrated the same pattern as the THAs, female TKAs displayed significantly less improvement in both OKS and its pain component following second-side surgery. CONCLUSION: Female patients undergoing second-side TKA showed less improvement in Oxford and pain scores compared to the first-side. This difference in outcome following second-side surgery did not apply to male patients undergoing TKA, or to either sex undergoing THA. Cite this article: Bone Jt Open 2021;2(4):243-254.

Is the KiRA Device Useful in Quantifying the Pivot Shift in Anterior Cruciate Ligament-Deficient Knees?

BACKGROUND: Various technologies have been developed to quantify the pivot shift, as it is regarded as a key indicator of anterolateral rotatory laxity of the knee. PURPOSE: To determine the usefulness of a commercially available triaxial accelerometer (Kinematic Rapid Assessment [KiRA]) in numerically quantifying the pivot shift in patients under anesthesia with an anterior cruciate ligament (ACL)-deficient knee. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: Both knees of 50 patients (26 male [mean age, 30.4 years], 24 female [mean age, 26.6 years]) under anesthesia were assessed immediately before unilateral ACL reconstruction by an orthopaedic fellow and 1 of 3 experienced knee surgeons. The pivot-shift grade and 2 KiRA outputs (range of acceleration and slope of acceleration change) were compared. RESULTS: The surgeon and fellow recorded the same pivot-shift grade for 45 of 50 patients (90%). Data from the 5 patients with no agreement and 1 patient with extreme outlying data were excluded from subsequent analysis. Using the KiRA range and slope data, the surgeon identified the injured knee in 74% and 76% of patients, respectively, while the fellow's rate of injured knee identification was 74% and 80%, respectively. A correlation could be found only between pivot-shift grade and surgeon-derived range data (ρ = 0.40; P < .01) but not slope data or any fellow-derived outputs. Using the surgeon-derived range data, there was a significant difference between a grade 3 pivot (>5 m/s2) and a grade 1 or 2 pivot (<5 m/s2) (P = .01). CONCLUSION: Although a correlation between KiRA output data and pivot-shift grade was found when the device was used by an experienced surgeon, there was no correlation when used by a well-trained but less experienced orthopaedic fellow. Furthermore, the KiRA output data identified the ACL-deficient knee correctly in only 74% of patients. Although a threshold acceleration range value could be identified, above which the value was associated with a grade 3 pivot shift, this was dependent on the examiner, and distinction between other grades could not be made.

Increased Radiographic Posterior Tibial Slope Is Associated With Subsequent Injury Following Revision Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Increased posterior tibial slope has been identified as a possible risk factor for injury to the anterior cruciate ligament (ACL) and has also been shown to be associated with ACL reconstruction graft failure. It is currently unknown whether increased posterior tibial slope is an additional risk factor for further injury in the context of revision ACL reconstruction. PURPOSE: To determine the relationship between posterior tibial slope and further ACL injury in patients who have already undergone revision ACL reconstruction. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 330 eligible patients who had undergone revision ACL reconstruction between January 2007 and December 2015 were identified from a clinical database. The slope of the medial and lateral tibial plateaus was measured on perioperative lateral radiographs by 2 fellowship-trained orthopaedic surgeons using a digital software application. The number of subsequent ACL injuries (graft rupture or a contralateral injury to the native ACL) was determined at a minimum follow-up of 2 years (range, 2-8 years). Tibial slope measurements were compared between patients who sustained further ACL injury to either knee and those who did not. RESULTS: There were 50 patients who sustained a third ACL injury: 24 of these injuries were to the knee that underwent revision ACL reconstruction, and 26 were to the contralateral knee. Medial and lateral slope values were significantly greater for the third-injury group compared with the no-third injury group (medial, 7.5° vs 6.3° [P = .01]; lateral, 13.6° vs 11.9° [P = .001]). CONCLUSION: Increased posterior tibial slope, as measured from lateral knee radiographs, was associated with increased risk of graft rupture and contralateral ACL injury after revision ACL reconstruction. This is consistent with the concept that increased posterior slope, particularly of the lateral tibial plateau, is an important risk factor for recurrent ACL injury.

Isolated Posterior Cruciate Reconstruction Results in Improved Functional Outcome but Low Rates of Return to Preinjury Level of Sport: A Systematic Review and Meta-analysis.

Background: Although isolated posterior cruciate ligament reconstruction (PCLR) has become a more frequently performed procedure, reports of functional outcomes and return-to-sport (RTS) rates to support its use are still limited. Purpose: To systematically review the literature to determine the rates of RTS and the functional outcomes of patients after isolated PCLR. Study Design: Systematic review: Level of evidence, 4. Methods: Two reviewers independently searched 5 databases for patient-based clinical studies with a minimum 2-year follow-up that analyzed functional outcome and RTS following isolated PCLR. Studies with multiligament knee reconstruction were excluded. Risk of bias was performed with a modified Downs and Black checklist. The primary outcomes were Tegner and Lysholm scores, rates of RTS, and International Knee Documentation Committee (IKDC) subjective scores. Secondary outcomes were IKDC objective scores, instrumented knee laxity assessment, and Telos radiographic analysis. Where feasible, these data were pooled via a random effects meta-analysis model. Results: Of the 240 titles identified, 14 studies were included. The median time from injury to surgery was 10.6 months (range, 6 weeks-21 years). The pooled mean postoperative Tegner and Lysholm scores were 5.7 (95% CI, 5.4-6.0) and 87.8 (95% CI, 85.6-90.0), respectively, following isolated PCLR; the pooled effect size between pre- and postoperative values was 2.8 (95% CI, 1.6-4.0) and 3.7 (95% CI, 2.6-4.9), respectively. An RTS rate of 44% (95% CI, 23%-66%) was identified. IKDC subjective scores improved to a pooled mean of 73.5 (95% CI, 62.8-84.1), with an effect size of 3.0 (95% CI, 0.4-5.6). The proportion of patients with postoperative IKDC objective scores of grade A/B was 82%. The pooled postoperative KT-1000/KT-2000 side-to-side difference was 3.4 mm (95% CI, 2.5-4.3 mm), with an effect size of 2.8 (95% CI, 1.1-4.5). The pooled postoperative Telos side-to-side difference measurement was 3.5 mm (95% CI, 2.8-4.3 mm), with an effect size of 3.9 (95% CI, 3.3-4.5). Conclusion: The results of this review demonstrate that while isolated PCLR results in a significant improvement in functional outcome scores and improved knee laxity, there is a low rate of return to preinjury level of sport. The prolonged period from injury to surgery might reduce functional improvement and RTS following reconstruction. Therefore, comparison of the outcomes of isolated PCLR and nonoperative treatment is impracticable owing to the potential for selection bias.

A prospective evaluation of a largely cementless total knee arthroplasty cohort without patellar resurfacing: 10-year outcomes and survivorship.

BACKGROUND: The theoretical benefits of a mobile bearing design in Total Knee Arthroplasty (TKA) include increased articular surface conformity with a reduction in both polyethylene wear and implant interface shear. However, to date these theoretical advantages have not been translated into published evidence of superior survivorship. This paper presents the results of a prospective, non-comparative study evaluating the performance of the mobile bearing Low Contact Stress LCS Complete Rotating Platform TKA in a largely cementless cohort without patellar resurfacing. METHODS: 237 consecutive patients (240 knees) undergoing primary TKA were prospectively recruited. All received the LCS Complete Rotating Platform TKA (DePuy International, Leeds, UK). Clinical and radiographic assessments were performed at 3, 12, 60 and 120 months post-operatively. Radiographic evaluation was performed by an independent external surgeon. RESULTS: The mean age was 70.3 years. 77.5% of cases were cementless. Radiographic assessment suggested excellent femoral component fixation. 22 tibial radiolucent lines (RLLs) > 1 mm were observed in 12 knees. No RLLs were progressive. There have been two revisions; one for late infection and one for aseptic loosening. No patients underwent secondary patellar resurfacing. The cumulative implant survivorship, using component revision for any reason as the endpoint, was 98.9% (95% CI, 95.6 to 99.7%) at 10 years. CONCLUSIONS: The excellent survivorship at a minimum 10-year follow-up supports the use of uncemented porous coated fixation without patellar resurfacing with the non-posterior stabilized LCS Complete Rotating Platform TKA.

The incidence of dissociated liners in 4,751 consecutive total hip arthroplasties using Pinnacle polyethylene acetabular liners.

INTRODUCTION: Acetabular liner dissociation is a complication exclusive to modular designs. We present a single surgeon series of 8 polyethylene liner dissociations with the Pinnacle Acetabular System (DePuy Orthopaedics) from over 4,750 cases. We also present a review of the literature and data from the UK National Joint Registry (NJR) on dissociation in total hip arthroplasty (THA). METHODS: The Pinnacle Acetabular System has been used exclusively by the senior author since April 2003, and to date 5,882 have been implanted (837 ceramic liners, 4,751 polyethylene liners (1,606 Enduron/3,145 Marathon) and 294 metal liners). We reviewed all cases of liner dissociation from this cohort to determine an overall incidence with polyethylene liners, identify associated risk factors, and report the outcome following revision surgery. RESULTS: Our incidence of this complication is 8 out of 4,751 cases (0.17%). Review of these cases and the literature suggests that femoral neck impingement against the polyethylene liner and/or edge loading may produce fatigue failure of the locking mechanism and subsequent dissociation. CONCLUSIONS: Ensuring correct liner seating/locking, minimising impingement, achieving appropriate component version and avoiding radiographic cup inclinations >50° should minimise the risk of liner dissociation. Any new noise or squeaking from a polyethylene liner should undergo radiographic investigation to exclude dissociation. We recommend managing late cases of liner dissociation with revision of the acetabular shell if the cup orientation could be improved or if there is any damage to the liner-locking groove, to reduce the risk of recurrence.

An Imperfect Peace: Trends In Paramilitary Related Violence 20 Years After The Northern Ireland Ceasefires.

BACKGROUND: The 1994 Northern Ireland ceasefire heralded a new beginning for the region after 30-years of violence. In the 20-years following the cessation of hostilities, paramilitary punishment attacks continue to occur in breach of the ceasefire. The aim of this study was to review trends in these attacks over the 20-years and their impact on orthopaedic services. METHODS: We conducted a retrospective review of patients admitted under orthopaedic services following paramilitary assault across Northern Ireland over the last 20-years. The frequency of assaults, demographics of the victim population, injury pattern and weapons used was determined. Data on the total number of attacks was obtained from the Police Service for Northern Ireland (PSNI). RESULTS: 3691 paramilitary style attacks occurred between 1994 and 2014 despite bilateral ceasefires. The overwhelming majority of attacks are on males, however females and children as young as 12 have been victims. Prior to 1994, penetrating trauma predominated (62% vs 38%), with blunt trauma more common post ceasefire (60% vs 40%). 33% of those injured required orthopaedic treatment. The type of weapon used in these assaults has changed primarily from ballistic to non-ballistic devices. CONCLUSIONS: We present data of paramilitary related trauma presenting to orthopaedic services across Northern Ireland in the 20-years since the conclusion of hostilities following the negotiated 1994 ceasefire. Many assaults continue to occur despite being in breach of the ceasefire. The frequency of these assaults is however, declining. The type of weapons used has changed resulting in less ballistic trauma and more blunt trauma. The injury pattern associated with blunt trauma has significant long-term morbidity and potentially a greater financial burden on the health service. IMPLICATIONS: 20-years of peace in Northern Ireland has had a hugely positive impact on the political and financial stability of the region. Unfortunately, continued violence represents a significant burden on the health service resources and causes potential long-term changes to victim's lives.

Acetabular Liner Dissociation following Total Hip Arthroplasty: A Rare but Serious Complication That May Be Easily Misinterpreted in the Emergency Department.

Acetabular liner dissociation is a rare complication of Total Hip Arthroplasty (THA) which requires urgent revision surgery. A case is presented in which the correct diagnosis was not appreciated on two separate Emergency Department attendances. The typical symptoms, signs, and radiological features are outlined and the importance of considering a rare complication following a commonly performed procedure is highlighted.

Recognition and management of Müller-Weiss disease.

BACKGROUND: Müller-Weiss disease (MWD) is an uncommon condition of unclear etiology, characterized by compression of the lateral aspect of the tarsal navicular bone. It presents with chronic mid and hindfoot pain, mostly in middle-aged females. It does not represent persistence of Kohler's disease, which is self-limiting and resolves completely in childhood. METHODS: A total of 12 patients with 19 affected feet, seven of whom had bilateral involvement, presented to a single foot and ankle surgeon over a 10-year period. Diagnosis of MWD was based on radiographic appearances demonstrating compression of the lateral part of the navicular. Affected feet were graded using Maceira classification. RESULTS: The cohort comprised four males and eight females with a mean age of 57.9 years. Only one patient had previously been a manual worker. Mean duration of symptoms was 5.2 years. Of the seven patients who underwent surgery for symptoms related to MWD, five had a triple arthrodesis, one had triple arthrodesis combined with naviculo-cuneiform fusion, and one had a pantalar arthrodesis for associated varus ankle osteoarthritis. Solid union was achieved in all cases. CONCLUSION: We propose that MWD is much more common than previously reported and did not find conditions of extreme environmental stress or poverty in our patients. We advocate surgical management of the condition by triple arthrodesis and extend it to include a naviculocuneiform fusion whenever indicated according to CT findings.