Local anatomical abnormalities vary in congenital hip disease patients. Authors often present early to mid-term total hip arthroplasty clinical outcomes using different techniques and implants randomly on patients with different types of the disease, making same conclusions difficult. We report long term outcomes (13 to 23 years) of the treatment of low and high dislocation cases (separately) with total hip arthroplasty using TM technology acetabular cups (Implex initially and then Zimmer) and short fluted conical (Zimmer) femoral stems. From 2000 to 2010, 418 congenital hip disease hip joints were treated in our department with total hip arthroplasty. According to Hartofilakidis et al's classification, 230 hips had dysplasia, 101 low dislocation, (group A) and 87 high dislocation (group B). Pre-operative and post-operative values, at regular intervals, of HHS, SF-12, WOMAC, OHS and HOOS were available for all patients. Patient, surgeon and implant related failures and complications were recorded for all patients. In all cases an attempt was made to restore hip center of rotation. In group A the average lengthening was 2.8 cm (range: 1 to 4.2) and in group B 5.7 cm (range: 4.2 to 11). In both groups, no hips were revised due to aseptic loosening of either the acetabular cup or the femoral stem. In group A, a cumulative success rate of 95.6% (95% confidence interval, 92.7% – 97.4%) and in group B a cumulative success rate of 94.8% (95% confidence interval, 92.6%–96.9%) was recorded, at 20 years, with revision for any reason as an end point. No s.s. differences were found between groups when mean values of HHS, SF-12, WOMAC and OKS were compared. Satisfactory long-term clinical outcomes can be achieved in treating different types of congenital hip disease when appropriate surgical techniques combined with “game changing” implants are used.
The aim of this study is the comparative assessment of long term clinical (subjective and objective), functional and quality of life outcome data between primary and revision THA. 122 patients (130 hips) who underwent cementless revision THA of both components (TMT cup, Wagner SL stem, Zimmer Biomet) for aseptic loosening only (Group A) were compared to a matched group of 100 patients (100 hips) who underwent cementless primary THA for osteoarthritis (Synergy stem, R3 cup, Smith & Nephew) (Group B). Outcomes were evaluated with survival analysis curves, Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford hip score (OHS), Short form-12 health survey (SF-12) and EQ-5D-5L scales. Mobility was assessed with walking speed, timed up and go test (TUG), Parker mobility, Lower extremity function score (LEFS) and UCLA scores. At a mean follow up of 14.4 years (10 to 20) a cumulative success rate of 96% (95% CI 96 to 99%) in Group A and 98% (95% CI 97 to 99%) in Group B with operation for any reason as an end point was recorded. Statistically significant differences between groups were developed for WOMAC (Mann-Whitney U test, p= 0.014), OHS (Mann-Whitney U test, p= 0.020) and physical component of SF-12 scores (Mann-Whitney U test, p= 0.029) only. In Group A, in multiple regression analysis, patients’ cognition (p=0.001), BMI (p=0.007) and pain (p=0.022) were found to be independent factors influencing functional recovery (WOMAC). Similarly, pain (p=0.03) was found to influence quality of life (EQ-5D-5). In the long term, revision THA shows satisfactory but inferior clinical, functional, and quality of life outcomes when compared to primary THA. Residual pain, BMI and cognitive impairment independently affect functional outcomes.
There are numerous studies in the current literature that have demonstrated altered levels of various biomarkers in the serum of patients with implant loosening. Despite increasing interest in the biology of implant incorporation there are no studies investigating the changes in biological marker (of either osteoblastic or osteoclastic activity) levels during the integration of the bone-implant interface. Such a study would provide data about the biological profile of normal integration and would be helpful for future monitoring of implant prosthetic performance (either normal or abnormal). We present data from a study performed on 100 osteoarthritic patients, who underwent cementless THA (Synergy, Reflexion Interfit, Smith & Nephew) and 100 non arthritic volunteers. Serial measurements of serum biochemical markers (bone formation and resorption), of cytokines and of other biological mediators and growth factors were evaluated at regular intervals over the course of six years. Curves of per cent changes from baseline and marker variability curves have been created for each marker which are indicative of the incorporation process. Evaluating markers of osteoblastic activity, a first response, with average values below baseline, was observed at the level of the seventh day (perhaps as a response to local trauma). A second osteo-productive response was observed between the third week and 9 months (peak average values at the level of the 6th month). At the 1st year time interval, average values reached baseline and remained at this level up to the 6th postoperative year. Evaluating markers of osteoclastic activity, a first response, with average values above baseline, was observed at the level of the seventh day (perhaps as a response to local trauma). A second osteoclastic response was observed between the third week and 3 months (perhaps a coupling response to enhanced osteoblastic activity). At 6 months, average values reached baseline and remained at this level up to the 6th postoperative year. It seems that bone implant interface in cementless total hip arthroplasty remains active up to the 9th postoperative month. Possible future deviation from such ‘individual normal’ curves will be indicative of the initiation of the osteolysis process and loss of fixation.
