No Difference Between Trabecular Metal Cones and Femoral Head Allografts in Revision TKA: Minimum 5-year Followup

Background

Encouraging clinical results have been reported with the use of femoral head structural allografts and, more recently, trabecular metal cones for the management of large structural defects of the femur and tibia during revision total knee arthroplasty (TKA). However, to our knowledge, there are no published studies comparing these two techniques.

Questions/purposes

Compared with bulk allografts, do trabecular metal cones result in (1) better validated outcomes scores; (2) a lower risk of loosening or revision at 5 years; and (3) fewer surgical complications when used for the management of bone loss in revision TKA?

Methods

Between 2002 and 2008, three surgeons performed 450 TKA revisions, 45 (10%) of which were performed using augmentation of host bone; in those, femoral head allograft was used in 30 (75%) and trabecular metal cones in 15 (25%). From 2002 to 2007, femoral head allografts were used in all patients (28 patients); from 2007 to 2008, trabecular metal augments were used in all patients. There was a period of 1 year (16 knees) in which there was some overlap; during that time, femoral head structural allografts were used in cases in which we were unable to fit the defect or achieve adequate stability with trabecular metal cones. Followup was at a mean of 9 years (range, 5–12 years). No patients were lost to followup. Knee function and quality of life were assessed using the Oxford Knee Score, WOMAC, SF-12, and the UCLA activity score. Radiographs were assessed for signs of loosening. Surgical complications included superficial or deep infections, iatrogenic fractures, symptomatic deep venous thromboses or pulmonary emboli, and blood loss requiring transfusion; these were obtained from our database and from review of patients’ charts.

Results

The mean Oxford Knee Score in the allograft and trabecular metal cone groups was 91 (SD 10) and 91 (SD 14), respectively (95% confidence interval [CI], 88–94; p = 0.29). Mean WOMAC scores were 94 (SD 10) and 92 (SD 14), respectively (95% CI, 80–105; p = 0.52) and mean UCLA scores were 6 (SD 1.2) and 6 (SD 1.5), respectively (95% CI, 4–8; p = 0.49). Five- and 10-year survivorship of the allografts was 93% (95% CI, 77–98) and 93% (95% CI, 77–99), respectively. Survivorship at a mean of 5 years in the trabecular metal cones group was 91% (95% CI, 56–98). With the numbers available, there were no differences between the groups in terms of the frequency of surgical complications (3% [one of 30] versus 7% [one of 15]; odds ratio, 0.5; p = 0.632).

Conclusions

With the numbers available, we found no difference in pain, function, or repeat revision when comparing femoral head allografts and trabecular metal cones for severe bone defects during revision TKA. However, we used allografts for the larger bone defects. Based on these results, we believe that femoral head allografts and trabecular metal cones can both be used for the management of Anderson Orthopaedic Research Institute Types 2 and 3 defects. Future multicenter studies are required with larger numbers, cost analyses, and a longer duration of followup.

Level of Evidence

Level III, therapeutic study.

     

Posterior Cruciate Mechanoreceptors in Osteoarthritic and Cruciate-retaining TKA Retrievals: A Pilot Study

Background  

Although normal cruciate ligaments and those in patients with osteoarthritic (OA) knees contain mechanoreceptors, it is unclear whether they are present after functioning in a cruciate-retaining total knee arthroplasty (TKA).     

Minimum 10-year results of a tapered cementless hip replacement.

Seventy-one total hip arthroplasties with a cementless, wedge fit, cobalt chrome femoral component were reviewed in 60 patients at a minimum 10-year followup (mean, 11.5 years). For the femoral component, the mechanical failure rate was 5% and the revision rate for aseptic loosening was 0%. The mean Charnley scores for pain, function, and motion changed from preoperative mean values of 3.0, 2.7, and 3.2 to followup mean values of 5.7, 5.5, and 5.2, respectively. The followup mean Harris hip Score was 91. The incidence of thigh pain was 1.4% at 10-year followup. Ninety-five percent of femoral components showed radiologic evidence of stable, bone ingrowth fixation, whereas loosening was seen in 5% of stems. Despite the high incidence of acetabular osteolysis, no osteolysis was seen on the femoral side distal to the lesser trochanter. Nonmodularity of the femoral component led to unavoidable revision of stably fixed femoral components in seven (9.8%) hips during the revision of a loose socket. Design features (collarless, tapered, wedge fit, and circumferentially porous coated) were thought to be crucial to the superlative results with the cobalt chrome femoral component.     

High Survivorship and Little Osteoarthritis at 10-year Followup in SCFE Patients Treated With a Modified Dunn Procedure

Clinical Orthopaedics and Related Research® - The modified Dunn procedure has the potential to restore the anatomy in hips with slipped capital femoral epiphyses (SCFE) while protecting the...     

Posterior-Stabilized TKA in Patients With Severe Genu Recurvatum Achieves Good Clinical and Radiological Results at 5-year Minimum Follow-Up: A Case-Controlled Study

BackgroundGenu recurvatum is a rare knee deformity. Total knee arthroplasty (TKA) in severe preoperative recurvatum requires surgical adjustments. Few studies have assessed the clinical and radiological results of TKA in recurvatum. The aim was to compare the clinical and radiological outcomes, complications, and revision rates after posterior-stabilized TKA in severe recurvatum with those without recurvatum.MethodsBetween 1987 and 2015, 32 primary posterior-stabilized TKA were performed with a preoperative genu recurvatum greater than 10° and minimum follow-up of 60 months. In severe genu recurvatum, the extension gap needs to be decreased compared with flexion gap. To achieve this, the distal femoral cut is distalized, whereas the posterior femoral and tibial cuts are performed as usual. They were compared with 64 matched posterior-stabilized TKAs without recurvatum. The demographic data were similar between groups. The clinical and radiological outcomes, complications, and revision rates were assessed at the last follow-up.ResultsAt a mean follow-up of 7.4 years ± 1.9, there was no significant difference in International Knee Score functional score (77.5 vs. 73.4; P = .50) and knee score (86.6 vs. 89.5; P = .37) between the recurvatum group and the control group, respectively. 6 patients had a postoperative recurvatum equal or superior to 10° in the recurvatum group (18.8%). There was no difference between both groups in radiological outcomes, complication, or revision rates. No instability was found in the recurvatum group.ConclusionPosterior-stabilized TKA with controlled distalization of the femoral component in the setting of severe preoperative genu recurvatum achieves good clinical and radiological outcomes at a minimum follow-up of 5 years and similar to TKA without preoperative recurvatum.Level of EvidenceIII.     

Tibial Component Alignment After Total Knee Arthroplasty with Intramedullary Instrumentation: A Prospective Analysis

The best operative technique for achieving appropriate postoperative alignment following total knee arthroplasty (TKA) remains controversial, with proponents of extramedullary, intramedullary and computer-assisted techniques. One hundred ninety-two consecutive patients undergoing TKA were prospectively evaluated with full-length lower extremity radiographs. Patients underwent cemented TKA using femoral and tibial intramedullary instrumentation. Digital radiographs were analyzed using PACS (AGFA Healthcare, Ridgefield Park, NJ) software. Tibial component alignment was measured in the coronal and sagittal planes. Tibial component slope averaged 3.89° + 1.96 for the cruciate-retaining components and averaged 1.7° + 1.92 for PS components. The average coronal tibial component alignment was 90.00°, and 99% were within 3° of neutral mechanical alignment with only 2 (1%) outliers. Intramedullary instrumentation resulted in excellent postoperative tibial component and lower extremity alignment.     

Tibial fractures in children: A retrospective 27-year follow-up study

Background

Tibial fracture is the third most common long-bone fracture in children. Traditionally, most tibial fractures in children have been treated non-operatively, but there are no long-term results.

Methods

94 children (64 boys) were treated for a tibial fracture in Aurora City Hospital during the period 1980–89 but 20 could not be included in the study. 58 of the remaining 74 patients returned a written questionnaire and 45 attended a follow-up examination at mean 27 (23–32) years after the fracture.

Results

89 children had been treated by manipulation under anesthesia and cast-immobilization, 4 by skeletal traction, and 1 with pin fixation. 41 fractures had been re-manipulated. The mean length of hospital stay was 5 (1–26) days. Primary complications were recorded in 5 children. The childrens’ memories of treatment were positive in two-thirds of cases. The mean subjective VAS score (range 0–10) for function appearance was 9. Leg-length discrepancy (5–10 mm) was found clinically in 10 of 45 subjects and rotational deformities exceeding 20° in 4. None of the subjects walked with a limp. None had axial malalignment exceeding 10°. Osteoarthritis of the hip and/or knee was seen in radiographs from 2 subjects.

Interpretation

The long-term outcome of tibial fractures in children treated non-operatively is generally good.Tibial fractures are among the most common long-bone fractures in children (Shannak 1988, Landin 1997, Mäyränpää et al. 2010). Primary complications such as vascular or nerve injuries or compartment syndrome are rare. Secondary complications include malunion and premature physeal closure in fractures extending to physis.Operative treatment has recently gained popularity, although most uncomplicated tibial fractures can be safely treated with closed reduction and cast-immobilization (Setter and Palomino 2006, Heinrich and Mooney 2010). There have been very few reports on the long-term results of tibial fracture treatment in children.Here we present long-term outcomes in children (< 15 years of age) who were treated for a tibial fracture in Aurora City Hospital, Helsinki during the period 1980–89. Aurora City Hospital was the primary treatment center for fractures in children in Helsinki during the study period.     

Minimum 10-year results of a tapered, titanium, hydroxyapatite-coated hip stem: an independent review

The performance of, and periprosthetic bone response to, a tapered, titanium (Ti6Al4V), hydroxyapatite-coated femoral hip prosthesis was evaluated at minimum of 10 years of follow-up. Data were prospectively collected on 147 consecutive primary hip arthroplasties performed in 133 patients by a single surgeon during a 2-year interval. Clinical and radiographic analyses of 96 hips in 86 patients were independently performed by 2 surgeons who were not involved in the care of these patients. There were no cases of aseptic loosening of the femoral component. Subsidence and stress shielding occurred in 5% and 2% of cases, respectively, and was not clinically significant. In all 15 hips that required revision of the acetabular component, the femoral component was found to be well fixed, without any occurrence of distal osteolysis. This femoral design provided reliable osseointegration that was durable at a mean of 11.5 years of follow-up.