Ceramic-on-ceramic total hip arthroplasty in patients younger than 55 years

Survival and complications of total hip arthroplasty using third-generation dual-mobility cups with non-cross-linked polyethylene liners in patients younger than 55years

BACKGROUND

In younger patients, total hip prostheses are subjected to wide motion ranges and wear-inducing forces. Dual-mobility cups (DMCs) are effective in decreasing the risk of dislocation. However, wear and osteolysis have been reported with first-generation DMCs. These complications have not been assessed in younger patients managed with third-generation DMCs associated with a lower risk of intra-prosthetic dislocation (IPD). We therefore designed a retrospective study of patients younger than 55years at THA with third-generation DMCs. Our objectives were to evaluate (1) the complication rate, and (2) the survival rate.

HYPOTHESIS

The rate of complications of THA with third-generation DMCs in patients younger than 55years of age is comparable to that in the general population of THA patients.

MATERIAL AND METHODS

This retrospective study included 79 consecutive patients (91 hips) who had total hip arthroplasty (THA) between 2007 and 2012. We included all patients younger than 55years who underwent primary THA with a third-generation DMC and a liner made of non-cross-linked polyethylene. The patients were evaluated clinically and radiologically.

RESULTS

Mean follow-up was 9.8years (range: 2-13years). At last follow-up, no patient had experienced prosthetic dislocation or IPD. Aseptic and septic cup loosening each occurred in 1 patient. In all, 7 (7.7%) patients required revision surgery with exchange of at least one component (cup loosening, n=2; neck fracture with a short stem fixed to the neck, n=1; peri-prosthetic femoral fracture, n=1; infection, n=1; and femoral-stem loosening, n=2). Peri-acetabular osteolysis developed in 2 (2.2%) hips. Cup survival to aseptic loosening was 98.9% (95% confidence interval, 97%-100%) and survival to revision for any reason except infection was 95.6% (95% confidence interval, 82%-100%).

DISCUSSION

In patients younger than 55years, third-generation DMCs were associated with absence of prosthetic dislocation, absence of IPD, and a low revision rate for cup loosening, in the medium term. These implants therefore constitute a viable treatment option in younger patients requiring THA.

LEVEL OF EVIDENCE

IV, retrospective study.

Surgeons’ Awareness and Impaction Technique of a Ceramic Liner into a Metal Shell

Background

In ceramic-on-ceramic total hip arthroplasty, firm locking is necessary between a ceramic liner and an acetabular metal shell to prevent dissociation of the liner from the metal shell. We evaluated surgeons’ awareness of the technique for inserting the ceramic liner and measured the impaction force applied by surgeons during the insertion of the ceramic liner.

Methods

To evaluate the awareness, we conducted a survey using a questionnaire including techniques for ceramic liner insertion. The impaction force was measured using an impaction simulator in 224 surgeons.

Results

Most surgeons answered that they cleaned and dried up the inner surface of the metal shell before inserting a ceramic liner (96.4% and 86.2%, respectively), and 74.6% checked the correct seating of the ceramic liner. However, only 23.2% correctly answered that a minimum of 2kN (a light strike) was necessary to obtain a sufficient fit between the metal shell and the ceramic liner. The impaction force was weaker than 2 kN in 9.4% of the surgeons.

Conclusions

Education about the adequate impaction force to obtain a firm fit of the ceramic liner is necessary for surgeons who perform total hip arthroplasty using ceramic-on-ceramic bearings.

Return to sports and work after partial shoulder replacement surgery

BACKGROUND

Shoulder hemiarthroplasty is a particularly attractive treatment option in young active patients, where revision surgery is an issue and a glenoid replacement might be necessary in the long run. These patients often ask about the possibility of returning to sport and work after surgery.

OBJECTIVE

The purpose of this investigation was to analyze whether patients undergoing shoulder hemiarthroplasty (HSA) are able to successfully return to sports activities and work after surgery.

MATERIALS AND METHODS

This study included 42 patients treated with HSA. Two subgroups were built: patients who had participated in sports less than 5 years prior to surgery (group A: n = 29, 69%) and those who had not done so (group B: n = 13, 31%). Evaluation was based on a questionnaire asking about types of sports, frequency of sports activity, and the time taken to return to sports and work, as well as about limitations in occupational life.

RESULTS

Patients' mean age at the time of surgery was 56.3 ± 12.7 years in group A and 66.9 ± 13.8 years in group B. Mean follow-up was 5.5 years (range 2.5-12 years). In group A, 18 patients (62%) had participated in sports up to the time of surgery and 12 (41%) had returned to the same level of sports activity at final follow-up. The rate of return to preoperative sports activity was 67%. Swimming was one of the most favorable sports (92%). Of the cohort patients, 2 (5%) had to change their profession due to surgery. Most patients were retired at follow-up.

CONCLUSION

Patients who were sportingly active prior to HSA were able to return to sports after surgery in 67% of cases. This study confirms that patients treated by hemiarthroplasty of the shoulder joint can return to sports and work, even at medium-term follow-up.

Getting back in the game after humeral head resurfacing

Background

Aim of this investigation was to analyze whether patients undergoing humeral head resurfacing (HHR) surgery are able to successfully return to their sports and occupation afterwards.

Materials and methods

Fifty patients treated with CUP (HHR) arthroplasty were included. Two groups were built: Patients who have participated in sports less than 5 years prior surgery (Group 1: n = 42 (84%)) and patients who have never participated in sports (Group 2: n = 8 (16%)). Evaluation was based on a questionnaire asking for types of sports, frequency, time to return to sports and work as well as limitations in work life.

Results

Mean age at the time of surgery was 58.6 (36-84) years in Group 1 and 65 (56-75) years in Group 2. Mean time follow-up was 5.5 years (2.5-12) years. Twenty-seven (64%) patients in Group 1 participated in sports right before surgery. Twenty-one patients (50%) returned to sports after surgery. The returning rate was 78%. Seven (17%) patients in Group 1 stated that the reason they underwent shoulder replacement surgery was to continue to participate in sports. Swimming and skiing were two of the most favorable sports. Two (4%) patients had to change their profession due to surgery. Most of the patients were retired at follow-up.

Conclusion

Most of the active patients undergoing HHR surgery are successfully able to return to their sports activities after surgery. Patients employed were able to return to their occupation after surgery. Many patients were already retired at the time of follow up.

Patient Satisfaction Reporting After Total Hip Arthroplasty: A Systematic Review

This review evaluated the quality of patient satisfaction reporting after total hip arthroplasty. The initial search of the MEDLINE database yielded 755 studies. Twenty-four met the inclusion criteria. Most studies provided level III or IV evidence (n=15, 62.5%). The most common method used to assess satisfaction was the 10-point visual analog scale (7 studies, 29.2%), followed by an ordinal satisfaction scale (6 studies, 25.0%). The quality of evidence was poor, and the methods used to assess satisfaction were not standardized. Further research is needed to define the factors that affect patient satisfaction after total hip arthroplasty and how satisfaction is best measured. [Orthopedics. 2017; 40(3):e400-e404.].

Finite element model of the impaction of a press-fitted acetabular cup

Press-fit surgical procedures aim at providing primary stability to acetabular cup (AC) implants. Impact analysis constitutes a powerful approach to retrieve the AC implant insertion properties. The aim of this numerical study was to investigate the dynamic interaction occurring between the hammer, the ancillary and bone tissue during the impact and to assess the potential of impact analysis to retrieve AC implant insertion conditions. A dynamic two-dimensional axisymmetric model was developed to simulate the impaction of the AC implant into bone tissue assuming friction at the bone-implant interface and large deformations. Different values of interference fit (from 0.5 to 2 mm) and impact velocities (from 1 to 2 m.s^-1) were considered. For each configuration, the variation of the force applied between the hammer and the ancillary was analyzed and an indicator I was determined based on the impact momentum of the signal. The simulated results are compared to the experiments. The value of the polar gap decreases with the impact velocity and increases with the interference fit. The bone-implant contact area was significantly correlated with the resonance frequency (R ² = 0.94) and the indicator (R ² = 0.95). The results show the potential of impact analyses to retrieve the bone-implant contact properties.