Lymphocoele: a rare and little known complication of anterior lumbar surgery

Lymphocoele is a rare and little known complication with only a handful of reports available. We report two cases of lymphocoele after anterior lumbar surgery that have occurred in two different centres and discuss diagnosis and management options. The first case is that of a 53-year-old male patient undergoing two level anterior lumbar interbody fusion (ALIF) for disabling back pain due to disc degeneration in the context of an old spondylodiscitis. He developed a large fluid mass postoperatively. Fluid levels of creatinin were low and intravenous urography ruled out a urinoma suggesting the diagnosis of a lymphocoele. Following two unsuccessful drainage attempts he underwent a laparoscopic marsupialization. The second case was that of a 32-year-old female patient developing a large fluid mass following a L5 corpectomy for a burst fracture. She was treated successfully with insertion of a vacuum drain during 7days. Lymphocoele is a rare complication but should be suspected if fluid collects postoperatively following anterior lumbar spine procedures. Chemical analysis of the fluid can help in diagnosis. Modern treatment consists of laparoscopic marsupialization. Lymph vessel anatomy should be borne in mind while exposing the anterior lumbar spin

Comparative effectiveness research across two spine registries

Background: Comparative effectiveness research in spine surgery is still a rarity. In this study, pain alleviation and quality of life (QoL) improvement after lumbar total disc arthroplasty (TDA) and anterior lumbar interbody fusion (ALIF) were anonymously compared by surgeon and implant. Methods: A total of 534 monosegmental TDAs from the SWISSspine registry were analyzed. Mean age was 42years (19-65years), 59 % were females. Fifty cases with ALIF were documented in the international Spine Tango registry and used as concurrent comparator group for the pain analysis. Mean age was 46years (21-69years), 78 % were females. The average follow-up time in both samples was 1year. Comparison of back/leg pain alleviation and QoL improvement was performed. Unadjusted and adjusted probabilities for achievement of minimum clinically relevant improvements of 18 VAS points or 0.25 EQ-5D points were calculated for each surgeon. Results: Mean preoperative back pain decreased from 69 to 30 points at 1year (ØΔ 39pts) after TDA, and from 66 to 27 points after ALIF (ØΔ 39pts). Mean preoperative QoL improved from 0.34 to 0.74 points at 1year (ØΔ 0.40pts). There were surgeons with better patient selection, indicated by lower adjusted probabilities reflecting worsening of outcomes if they had treated an average patient sample. ALIF had similar pain alleviation than TDA. Conclusions: Pain alleviation after TDA and ALIF was similar. Differences in surgeon's patient selection based on pain and QoL were revealed. Some surgeons seem to miss the full therapeutic potential of TDA by selecting patients with lower symptom severit

Comparative effectiveness research across two spine registries

Comparative effectiveness research in spine surgery is still a rarity. In this study, pain alleviation and quality of life (QoL) improvement after lumbar total disc arthroplasty (TDA) and anterior lumbar interbody fusion (ALIF) were anonymously compared by surgeon and implant

The contributions and limitations of hydroxyapatite coatings to implant fixation: A histomorphometric study of load bearing implants in dogs.

The contribution and limitation of hydroxyapatite coatings to implant fixation are discussed following a 5-year histomorphological study of the bony incorporation of macroporous stemless hemiarthroplasties in dogs. Implants without coating, with a pure titanium coating and with a hydroxyapatite coating were compared. The mean extent of direct contact between bone and hydroxyapatite-coated implants was 66% compared with 0 to 5% in the other implants. Areas of resorption of the coating were seen in every case associated with direct bone apposition on the metal surface. When the initial fixation is stable, osteointegration of hydroxyapatite-coated implants is obtained consistently, despite design features known to preclude bone incorporation. Implant fixation must depend on a mechanical interlock with bone because of the resorbability and mechanical properties of hydroxyapatite coatings

Development, experimental and clinical evaluation of a stemless hip prosthesis

The suppression of the medullary stem appears to be a logical solution to stress shielding if a long-term implant fixation can be obtained without medullary anchoring. Our experimental work demonstrated that this can be achieved. The analysis of the mean 6-year follow-up results of this innovative THR allow to draw several conclusions. By its design, the implant ensures the preservation of the cancellous bone and the vascularisation of the proximal metaphysic of the femur by the time of implantation. The prospective DXA study demonstrates the absence of proximal bone resorption and even an increase of bone mineral density on those patients with initial values. The cumulative survival rate for the whole group with a maximum follow-up of seven years is 83%. These results remain acceptable taking into account that they are obtained in a group of young and mostly active patients and that they incorporate the “learning curve” of a truly innovative implant. The early failures which occurred in the first clinical trial are all related to precisely identified errors of implantation for which the implant is unforgiving. Most of these errors are now prevented by appropriate surgical techniques and instrumentation. This was demonstrated in over 50 consecutive cased operated with a modified ancillary instrumentation. No failure occurred in patients with well-positioned implants. The functional results obtained in the remaining group of young and mostly active patients are remarkably good with a 17.4/18 Postel-Merle d’Aubigné score, a 97.4 Harris hip score and a mean 90.7-100 Johansson functional score. The procedure seems particularly appropriate in terms of pain relief. There was not a single case of thigh pain at any time during the follow-up and non patient complained of more than minor and intermittent discomfort. Most patients consider their operated hip as fully normal and are not even aware that has been operated. The radiographic analysis does not show any femoral component migration in the remaining group of patients. Minor acetabular component migration has been seen in a few cases. Because of the implant design, revision surgery is remarkably easy without any risk of weakening or loss of femoral bone. Given the precise explanation of the early failures, their effective prevention achieved with improved instrumentation and, with the excellent clinical and radiological results obtained when the prosthesis was correctly implanted, the clinical trial was resumed in 1995. The indication remains limited to young patients. A stemless femoral component is a genuine solution for the preservation of bone stock. Clinical and experimental results indicated the soundness of the concept whenever the implant is correctly positioned. These conclusions need to be further confirmed in our hands with a longer follow-up, and, later, in a multicentric clinical trial, prior to any larger diffusion.Thèse d'agrégation de l'enseignement supérieur (Faculté de médecine) -- UCL, 199

Fixation and effect on bone strain pattern of a stemless hip prosthesis.

Given the relatively short survival time of total hip replacement in young patients, a different concept of femoral implant was designed and evaluated biomechanically prior to clinical application. The femoral component has no intramedullary stem and fits into an angular resection of the femoral neck. A trans-trochanteric screw provides immediate strong fixation. A comparative biomechanical study with cadaver femora and a dynamic hip simulator was performed. The study had three objectives. (1) The strains generated under loading in the intact proximal femur were compared to those generated in the presence of the experimental implant and a classic cemented implant. (2) The short-term stability of the experimental prosthesis under loading conditions encountered during fast walking was evaluated. (3) Most importantly, the implant design was improved in the light of the experimental observations prior to any clinical trial. Indeed, the prototype underwent several important modifications in the course of the study. With the modified design, later used in a clinical trial, it was demonstrated that if accurate fit and position of the prosthesis were provided, fixation remained sound for over one million loading cycles with peak loads of three times the body weight. The measured interface micromotion was compatible with direct bone apposition and ingrowth. No statistical difference was found between the strain measurements obtained before and after implantation of the experimental prosthesis whereas significant stress shielding was observed with a stemmed, cemented prosthesis

Mechanical simulator for the upper femur.

This paper describes a simulator designed to evaluate the mechanical behaviour of the proximal femur and the influence of a prosthesis on this behaviour. Cyclic dynamic loads, corresponding to those generated by walking or several other activities, are applied to the proximal end of a fresh cadaveric femur before and after implantation of different types of hip prosthesis. Three musculoaponeurotic groups are modelled (abductor group, fascia lata and vastus lateralis). Load cells and strain gauges coupled to a data acquisition system are used to measure and record the forces on the femoral head and in the different muscle groups, as well as the strain variations occurring in the bone. Displacement transducers monitor the displacements occurring about the bone/implant interface