A comparison of function after limb salvage with non-invasive expandable or modular prostheses in children

BackgroundModular and non-invasive expandable prostheses have been developed to provide a functional knee joint that allows future expansion as growth occurs in the contralateral extremity in children with bone sarcomas that require removal of the growth plate. This study aimed to evaluate the functional outcomes of paediatric patients who received either a non-invasive expandable or modular prosthesis for bone sarcomas arising around the knee.MethodsWe evaluated clinician-reported, patient-reported and measured function in 42 paediatric patients at least one year (median age at assessment 19.1 years) after limb salvage surgery, and compared patients who received modular system prostheses (N = 29, median age 15.5), who did not require lengthening procedures to those who received non-invasive expandable prostheses (N = 13, median age 11.1) requiring lengthening procedures (median 5).ResultsThe number of revisions and time to first revision did not differ between the two groups. There were no differences between the two groups in total scores on the Enneking Musculoskeletal Tumor Society Scale, the Toronto Extremity Salvage Scale, and the Functional Mobility Assessment. Children with non-invasive expandable prostheses climbed stairs (11.93 ± 4.83 versus 16.73 ± 7.24 s, p = 0.02) in less time than those with modular prostheses.ConclusionOur results suggest that the non-invasive expandable prosthesis produces similar functional results to the more traditional modular prosthesis.     

Image-guided periacetabular osteotomy: computer-assisted navigation compared with the conventional technique: A randomized study of 36 patients followed for 2 years

Background?Periacetabular osteotomy (PAO) is an effective but technically demanding surgical procedure. We evaluated the efficiency of computer-assisted navigation in PAO and compared it with the traditional approach.

Patients and methods?We performed a randomized study of 36 patients undergoing PAO using either the CT-based, computer-assisted navigation technique or the conventional approach. The operative details, radiographic results, and functional outcomes were compared between groups.

Results?Patients in the conventional surgery group required an average of 4.4 (2–7) images of intraoperative radiographs, whereas only 0.6 (0–1) images were required in the navigation group. The operation time was 21 min shorter with computer-assisted navigation. No significant difference with regard to operative blood loss, transfusion requirement, correction of deformity, and functional improvement was found. Complications such as intraarticular damage, osteonecrosis, or neurovascular injury were not encountered.

Interpretation?A computer-assisted navigation system is a feasible tool to provide real-time image guidance and facilitate PAO. However, it offers little additional benefit when the surgery is done by an experienced surgeon.     

Efficacy of proprioceptive neuromuscular facilitation techniques versus traditional prosthetic training for improving ambulatory function in transtibial amputees

The objective of this randomized controlled trial was to evaluate the efficacy of proprioceptive neuromuscular facilitation (PNF) techniques in comparison to traditional prosthetic training (TPT) in improving ambulatory function in transtibial amputees. Thirty study participants (19 men and 11 women) with unilateral transtibial amputation participated in the study. They were randomly allocated to either the traditional training group (i.e., TPT) (n = 15) or the PNF training group (n = 15). The treatment in the TPT group consisted of weight-bearing, weight-shifting, balance, and gait exercises for 30 minutes daily for 10 treatment sessions. In the PNF group, the same activities were performed by employing PNF principles and techniques. The outcome measures were gait parameters (e.g., stride width, step length, and stride length) and the Locomotor Capabilities Index (LCI). The between-group comparisons at the end of the trial showed that the PNF group showed significant improvement in gait parameters and in the LCI, compared to the TPT group (p < 0.05). The results of the study suggested that prosthetic training based on proprioceptive feedback is more effective than the traditional prosthetic programme in improving ambulatory function.     

Fatigue resistance of yttria‐stabilized tetragonal zirconia polycrystal clasps for removable partial dentures

With the rapid development of computer‐aided design/computer‐aided manufacturing (CAD /CAM ) systems, the application of zirconia in removable partial dentures is expected to expand. Clasps composed of zirconia should improve esthetics without inducing the risk of metal allergy. The aim of this study was to examine the fatigue resistance of yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) clasps for removable partial dentures. Yttria‐stabilized tetragonal zirconia polycrystal and cobalt‐chromium (Co‐Cr) alloy were prepared using CAD /CAM systems. Specimens were either of the semicircular type or of the flat type, with cross‐sectional areas of taper ratios of 0.50, 0.75, and 1.00. All specimens were tested using the cantilever test and the constant displacement fatigue test, and data were analyzed using ANOVA . During the cantilever test, the maximum displacement prior to fracture was greater than the required undercut, and the semicircular‐type specimen exhibited a higher fracture load than the flat type. None of the specimens displayed permanent deformation and showed almost the same degree of deformation after fatigue testing. A lower taper ratio was associated with lower average load values and greater displacement. Within the limitations of this study, it was possible to conclude that Y‐TZP provides the required undercut and adequate retentive force for removable partial denture clasps. Additionally, Y‐TZP and Co‐Cr alloy had almost the same degree of deformation even after the simulated lifespan of removable partial dentures.     

Painful Hip Arthroplasty: What Should We Find? Diagnostic Approach and Results

IntroductionIdentifying the source of pain is paramount for determining appropriate treatment and ensuring successful outcome in terms of management and relief of pain. The difficulty is that each surgeon has his or her own way of seeing the problem, and there is no consensus for the evaluation of these patients. The study hypothesis was that it is possible to find the cause of the pain in most cases.Patients and methodsAll patients consulting for unexplained painful hip arthroplasty were included and followed a decision tree to assess the cause of the pain. The primary endpoint was the final diagnosis. Secondary endpoints were subgroup comparison between main causes and assessment of risk factors.ResultsTwo hundred one hips of 194 patients were included as unexplained painful hip arthroplasty 6 months postoperatively. Final diagnoses comprised periarticular pain in 53 cases (26.4%): 40 cases of trochanteric bursitis, 5 of iliopsoas tendinitis, 5 of abductor deficiency, 1 of ischial tuberosity tendinitis, and 2 of heterotopic ossification; projected pain in 49 (24.4%): 45 cases of back pain with or without neuropathy, 3 of knee osteoarthritis, and 1 of metabolic neuropathy; wear in 40 (19.9%), in the polyethylene liner; loosening in 20 (10.0%): loosening of the femoral component in 8 and that of the cup in 12; material problems in 17 (8.5%): trunnionosis in 13 and metallosis in metal-on-metal implants in 4; no diagnosis in 7 hips (3.5%); infection in 6 (3.0%), all chronic; instability without real dislocation in 3 (1.5%); misplacement in 3 (1.5%), all for leg-length discrepancy; fracture in 2 (1.0%): 1 of greater trochanter and 1 of ilio-ischiopubic ramus; complex regional pain syndrome in 1 (0.5%).DiscussionTo our knowledge, this is the first study on the causes of painful hip arthroplasty in clinical practice, whether leading to revision or not. A systematic approach, including physical examination, radiographic assessment and laboratory studies, is needed to find the cause of the pain. It is important to understand the pain so that it can be treated appropriately. Revision surgery can sometimes help—but the worst thing is to make the patient worse.Level of Evidencelevel 4, retrospective study.