The outpatient total hip arthroplasty : a paradigm change.

AIMS: To examine incidence of complications associated with outpatient total hip arthroplasty (THA), and to see if medical comorbidities are associated with complications or extended length of stay. PATIENTS AND METHODS: From June 2013 to December 2016, 1279 patients underwent 1472 outpatient THAs at our free-standing ambulatory surgery centre. Records were reviewed to determine frequency of pre-operative medical comorbidities and post-operative need for overnight stay and complications which arose. RESULTS: In 87 procedures, the patient stayed overnight for 23-hour observation, with 39 for convenience reasons and 48 (3.3%) for medical observation, most frequently urinary retention (13), obstructive sleep apnoea (nine), emesis (four), hypoxia (four), and pain management (six). Five patients (0.3%) experienced major complications within 48 hours, including three transferred to an acute facility; there was one death. Overall complication rate requiring unplanned care was 2.2% (32/1472). One or more major comorbidities were present in 647 patients (44%), including previous coronary artery disease (CAD; 50), valvular disease (nine), arrhythmia (219), thromboembolism history (28), obstructive sleep apnoea (171), chronic obstructive pulmonary disease (COPD; 124), asthma (118), frequent urination or benign prostatic hypertrophy (BPH; 217), or mild chronic renal insufficiency (11). CONCLUSION: The presence of these comorbidities was not associated with medical or surgical complications. However, presence of one or more major comorbidity was associated with an increased risk of overnight observation. Specific comorbidities associated with increased risk were CAD, COPD, and frequent urination/BPH. Outpatient THA is safe for a large proportion of patients without the need for a standardised risk assessment score. Risk of complications is not associated with presence of medical comorbidities. Cite this article: Bone Joint J 2018;100-B(1 Supple A):31-5.

The patient-specific Triflange acetabular implant for revision total hip arthroplasty in patients with severe acetabular defects: planning, implantation, and results.

AIMS: Few reconstructive techniques are available for patients requiring complex acetabular revisions such as those involving Paprosky type 2C, 3A and 3B deficiencies and pelvic discontinuity. Our aim was to describe the development of the patient specific Triflange acetabular component for use in these patients, the surgical technique and mid-term results. We include a description of the pre-operative CT scanning, the construction of a model, operative planning, and surgical technique. All implants were coated with porous plasma spray and hydroxyapatite if desired. PATIENTS AND METHODS: A multicentre, retrospective review of 95 complex acetabular reconstructions in 94 patients was performed. A total of 61 (64.2%) were female. The mean age of the patients was 66 (38 to 85). The mean body mass index was 29 kg/m2 (18 to 51). Outcome was reported using the Harris Hip Score (HHS), complications, failures and survival. RESULTS: The mean follow-up was 3.5 years (1 to 11). The mean HHS improved from 46 (15 to 90) pre-operatively to 75 (14 to 100). A total of 21 hips (22%) had at least one complication with some having more than one; including dislocation (6%), infection (6%), and femoral complications (2%). The implant was subsequently removed in five hips (5%), only one for suspected aseptic loosening. CONCLUSION: The Triflange patient specific acetabular component provides predictable fixation with complication rates which are similar to those of other techniques. Cite this article: Bone Joint J 2018;100-B(1 Supple A):50-4.

Advances in pain management: game changers in knee arthroplasty.

Over the past 30 years there have been many improvements in implant fixation, correction of deformity, improved polyethylene wear, and survival after knee replacement. The work over the last decade has focused on less invasive surgical techniques, multimodal pain management protocols, more rapid functional recovery and reduced length of stay, aiming to minimise the side effects of treatment while maintaining function and implant durability. When combined and standardised these pre-, intra- and post-operative factors have now facilitated outpatient knee replacement procedures for unicompartmental replacement, patella femoral arthroplasty and total knee replacement (TKR). We have found liposomal bupivacaine, with potential for longer therapeutic action, to be a helpful adjunct and describe our current pain management program. The next step in our multimodal program is to improve the duration of patient satisfaction and reduce cost and length of stay after TKR.

Hip and knee arthroplasty 2011: what's new, what's true, does it matter? Evidence based issues.

This conversation represents an attempt by several arthroplasty surgeons to critique several abstracts presented over the last year as well as to use them as a jumping off point for trying to figure out where they fit in into our current understanding of multiple issues in modern hip and knee arthroplasty.

Long-term deterioration of joint evaluation scores.

We investigated the long-term changes in the Harris Hip and Knee Society scores (HSS and KSS) to determine whether they result from overall functional decline rather than actual changes in the condition of the prosthesis. The HHS for 106 total hip arthroplasties with a minimum follow-up of ten years, no medical complications after operation and no evidence of radiological loosening, and the KSS for 264 total knee arthroplasties with a minimum follow-up of 12 years and no medical complications after operation or signs of radiographical loosening were evaluated. There were statistically significant drops in the functional scoring components of the joint evaluation systems despite no loosening of the prostheses or other significant medical complications. The HHS declined at an average of 0.67 points per year from between three and ten years after operation (p < 0.0001). Contributing to this were deterioration in gait and limp (p < 0.0004), the use of support aids (p < 0.0001), the distance walked (p < 0.0001) and the ability to climb stairs (p < 0.0455). The functional component of the KSS declined significantly at an average 0.88 points per year betwen the third and 12th years (p < 0.0001). There were significant declines in every component of the functional score including the distance walked (p < 0.0001), the ability to climb stairs (p < 0.0001) and the use of support aids (p < 0.0001). The knee score component of the KSS did not decline significantly (p < 0.9750). The combination of functional and pain scores within the HHS system leads to an inaccurate decline in the entire score. The decline of HHS and Knee Society functional scores in total joint arthroplasties, in the absence of implant-related problems, suggests that deterioration in the functional capacity of ageing patients is an important factor in longitudinal studies using these scoring systems.

Intra-operative findings in varus osteoarthritis of the knee. An analysis of pre-operative alignment in potential candidates for unicompartmental arthroplasty.

Interest in unicompartmental knee arthroplasty (UKA) for the treatment of medial compartment osteoarthritis has increased in recent years with apparent improvement in the long-term results. This is a result of improved surgical technique, patient selection, and implant design. In an effort further to improve patient selection we analysed the relationship between the pre-operative alignment of the knee and the anatomical findings at the time of surgery. We compared these findings with the indications for UKA. From 4021 total knee arthroplasties we compared intra-operative observations with the pre-operative clinical data in order to identify knees with isolated, medial, compartment changes, which would have been ideal candidates for UKA. We found that only 247 of the knees (6.1%) met anatomical qualifications for isolated, medial, unicompartmental osteoarthritis, and of these, only 168 (4.3%) met clinical standards ideal for UKA. Preoperative alignment showed a significant relationship with patterns of disease. Logistic regression revealed a relationship between pre-operative alignment and intraoperative findings resembling a Gaussian distribution. Patients with a pre-operative varus alignment of 7 degrees were slightly more likely to be selected for UKA. But the further the anatomical alignment in either direction varies from 7 degrees of varus, the more unlikely it is for the knee to exhibit a disease pattern of isolated, medial, unicompartmental osteoarthritis.

Metal-backed patellar components: a brief report on 10-year survival.

Two hundred ninety-six total knee arthroplasties were performed with metal-backed patellar components in 206 patients with an average followup of 10 years. These total knee arthroplasties were reviewed retrospectively for survivorship, failure, and revision. There were 28 patellar component failures in 24 patients. Eighteen patellar components required revision. The average time to failure was 6.8 years. The average time to revision was 6.3 years. Survivorship analysis revealed .9662 survivorship at 5 years, which decreased to .8976 at 10 years, and .8641 at 14 years. These results do not compare favorably with the results of total knee arthroplasty with all-polyethylene patellar components. The use of metal-backed patellar components should be avoided.

The failure of all-polyethylene patellar components in total knee replacement.

The patellar component of total knee replacement is the most frequent source of nonseptic complications after total knee arthroplasty. The purpose of the current study was to review the radiographic factors associated with loosening of all-polyethylene patellar components. Four thousand five hundred eighty-three cases of Anatomic Graduated Components total knee replacements were performed at the authors' institution during the past 15 years. Radiographs were reviewed and loosening was defined as global radiolucency or component migration. Four thousand two hundred eighty-seven allpolyethylene patellar components were implanted. There were 180 (4.2%) loose all-polyethylene patellar components. The mean time to loosening was 2.6 years (+/- 1.75 years). Fifteen (0.3%) patellar components required revision. Five radiographic features were associated with failure. The incidence and mean time of appearance were recorded: (number; incidence; time) (1) Bone-cement radiolucency, n = 174, 96.7%, 1.4 years; (2) increased density, n = 118, 65.6%, 1.8 years; (3) trabecular collapse of the bone, n = 160, 88.9%, 2.3 years; (4) patella fracture and fragmentation, n = 133, 73.9%, 2.5 years; and (5) lateral subluxation of the residual patella bone, n = 146, 81.1%, 2.9 years. Lateral retinacular release was associated with an increased rate of patellar loosening. Loosening of the allpolyethylene patella component is an avascular process strongly associated with lateral retinacular release and for which the patient infrequently requires revision surgery.

Long-term followup of anatomic graduated components posterior cruciate-retaining total knee replacement.

The purpose of the current study was to evaluate the authors' 15-year experience with the Anatomic Graduated Components total knee replacement. This is a report of the survivorship of 4583 Anatomic Graduated Component total knee arthroplasties. Kaplan-Meier survival analyses were performed with the end point defined as radiographic loosening, revision, or both. This end point was subdivided into the best case scenario in which it was assumed that all the patients lost to followup were doing well throughout the study and a worst case scenario in which it was assumed that all patients lost to followup had failed results at their last clinic visit. There were six (0.18%) femoral, 21 (0.46%) tibial, and 180 (4.2%) all-polyethylene patellar component failures secondary to aseptic loosening. All femoral components and 90% of the tibial components were revised; however, only 15 patellar components were revised. The clinical survival rate with revision of one or more of the components was 98.86% at 15 years. Despite having nearly flat-on-flat geometry and retaining the posterior cruciate ligament, which should increase the stresses in the polyethylene and at the bone-cement interface, this total knee replacement has proved to have minimal wear and excellent longevity with time. The authors think this is a result of the direct compression molded polyethylene articulation and the nonmodular configuration that incorporates metal backing on the tibial component and eliminates back-sided tibial component polyethylene wear.

Total knee replacement in patients with genu recurvatum.

Between June 1987 and March 1997, 57 total knee replacements were done in 53 patients with at least 5 degrees hyperextension deformity as measured on physical examination. The average recurvatum measured 11 degrees (range, 5 degrees-20 degrees). No cases of major ligamentous instability, neuromuscular disease, or inflammatory arthropathy were identified before surgery. Before surgery, Knee Society knee, function, and pain scores averaged 41 points, 41 points, and 13 points, respectively. A posterior cruciate-retaining prosthesis was implanted in all patients. The followup averaged 4.5 years (range, 3-10 years). Knee, function, and pain scores improved to 81 points, 78 points, and 43 points, respectively. Postoperative extension averaged 0 degrees (neutral) (range, 10 degrees hyperextension-10 degrees contracture). Only two (3.5%) knees had a hyperextension deformity after surgery. Both deformities measured 10 degrees and were in patients with a preoperative diagnosis of osteoarthritis. At final followup, no knee replacement was revised for any reason. In addition, only one case of a progressive radiolucent line greater than 1 mm (tibial Zone 7) was observed. Although the etiology of a hyperextension deformity should be elucidated before surgery, its presence does not preclude a well-functioning total knee replacement.

Technical considerations of cemented acetabular components: a 30-year evaluation.

The effect of porosity reduction cementing techniques with respect to radiolucent lines in Zone 1 and failure in acetabular components was studied in 2,237 consecutive cemented acetabular components done between 1970 and 1998. The minimum followup was 2 years. Radiolucencies in Zone 1 on initial radiographs obtained postoperatively were tabulated for five groups of patients based on cementing techniques. The percentage of loose or revised cups was calculated for six groups based on type of prosthesis used. The lowest percentage of Zone 1 radiolucencies was in a group in which bowl mixing was used. The lowest failure rate was in the group that received Charnley prostheses in which simple first generation cement techniques were used. Porosity reduction techniques did not reduce the incidence of Zone 1 radiolucencies. For the acetabular side of a total hip replacement, the biology of the bone and the techniques of cement insertion that include a dry cancellous bone bed, perforation and removal of peripheral sclerotic areas, pressurization of the entire cement mantle in the socket at one time, and complete burying of the acetabular component within the boundary of the bony acetabulum are the essential factors, not porosity reduction in the cement.

Radiological factors influencing femoral and acetabular failure in cemented Charnley total hip arthroplasties.

We have made a retrospective review of 185 cemented Charnley total hip arthroplasties performed between 1970 and 1974 to determine the relationships between radiological variables and failure of the femoral and acetabular components. We measured the acetabular wear, the orientation of the cup, the thickness and consistency of acetabular and femoral cement mantles, radiolucency and femoral alignment. The mean follow-up was for 11.7 years. Femoral loosening was demonstrable radiologically in 15 hips (8.1%), ten (5.4%) of which were revised during the period of follow-up. Only when the first postoperative radiograph showed a thin cement mantle in Gruen zone 5 was there a significant association with failure of the femoral component. There were 12 loose acetabular components (6.5%), nine (4.8%) of which were revised. When the initial radiograph after operation showed radiolucency in DeLee and Charnley zone 1, the incidence of acetabular loosening was 28.21%. If such radiolucency was not present, the incidence of acetabular loosening was only 0.69%. Our findings emphasise the importance of careful cementing.

A biomechanical comparison of intramedullary nail and crossed lag screw fixation for tibiotalocalcaneal arthrodesis.

This study compared the mechanical bending and torsional properties of intramedullary nail fixation and lag screw fixation for tibiotalocalcaneal arthrodesis. Seven matched pairs of human cadaver lower extremities were studied, with one hindfoot in each pair stabilized with a 12 mm x 150 mm interlocked intramedullary nail inserted retrograde across the subtalar and ankle joints. The contralateral hindfoot was stabilized with two crossed 6.5 mm cannulated screws inserted across both the ankle and subtalar joints. Specimens were subjected to cantilever bending tests in plantarflexion, dorsiflexion, inversion, and eversion and to torsional tests in internal and external rotation. The intramedullary nail construct was significantly (P < 0.05) stiffer than the crossed lag screw construct in all four bending directions and both rotational directions: plantarflexion (nail, 42.8 N/mm; screws, 16.4 N/mm; P = 0.0003), dorsiflexion (nail, 43.0 N/mm; screws, 10.3 N/mm; P = 0.0005), inversion (nail, 37.7 N/mm; screws, 12.3 N/mm; P = 0.0024), eversion (nail, 35.4 N/mm; screws, 10.8 N/mm; P = 0.0004), internal rotation (nail, 1.29 N-m/degree; screws, 0.82 N-m/degree; P = 0.01), external rotation (nail, 1.35 N-m/degree; screws, 0.44 N-m/degree; P = 0.0001). Intramedullary fixation is biomechanically stiffer than crossed lag screws in all bending and torsional directions tested and therefore this construct may aid in maintaining alignment of the hindfoot during union and may help increase fusion rate through increased stability of the internal fixation.

The natural history of mammographic calcifications subjected to interval follow-up.

The purpose of this investigation was to determine the natural history and risk of malignancy associated with isolated indeterminate microcalcifications subjected to interval follow-up. During a 2-year study, 91 patients were identified with indeterminate microcalcifications alone. Specific roentgenographic features of the calcifications were evaluated on initial and follow-up mammograms. During a mean follow-up of 36 months, 19 (21%) of the women exhibited mammographic changes. Ten patients (11%) with suspicious changes underwent a needle-directed biopsy 6 to 30 months after the initial mammographic screening. Five women (5.5%) were diagnosed as having breast carcinoma; three had invasive ductal carcinoma and two had purely intraductal lesions. Four patients had axillary lymph node dissections and no metastatic disease was found. We found no significant differences in the roentgenographic features associated with malignant vs benign lesions apart from an increased overall estimation of the probability of malignancy rating in the five patients with breast carcinoma. We recommend that patients be followed up with mammography at regular intervals for at least 18 months following recognition of indeterminate microcalcifications.

Leakage of intraluminal low molecular weight polyethylene glycol as a marker of small bowel transplant rejection.

To facilitate early detection of small bowel allograft rejection, we correlated transluminal leakage of low molecular weight polyethylene glycol (PEG) with the development of allograft rejection. Vascularized allogeneic and syngeneic jejunal transplants were performed in rats, without immunosuppression. A control group underwent creation of jejunal Thiry-Vella fistulas of similar length. Jejunal segments were perfused with a physiologic solution containing [3H]-PEG-900. At the end of an equilibrium period, an urinary bladder aspirate was collected and [3H]-PEG-900 measured by scintillation counting. Results are expressed as disintegrations per minute per 100 microL urine. Histologic examinations were performed at all experimental time points. Two days following transplantation, urinary PEG levels were elevated in both allogeneic and syngeneic groups (3943 +/- 935 and 4007 +/- 1164, respectively). Four days after the transplant, syngeneic urine PEG levels decreased to 581 +/- 159, and were not significantly different (P greater than .05) from Thiry-Vella controls (635 +/- 145). Syngeneic levels remained at this low level for the rest of the experiment. The allogeneic group continued to show significantly higher levels (P less than .05) compared with syngeneic and Thiry-Vella groups from day 4 until the end of the experiment. These elevated levels most likely represented the development of rejection, preceding the first significant histologic signs of rejection, which were found at six days post-transplant. Detection of transluminal leakage of low molecular weight PEG may be a useful adjunct in monitoring for small bowel transplant rejection.