Options and limitations of implant constraint.

With an ever-increasing number of revisions, the surgeons will be faced with the dilemma of choosing the right implant for the revision knee. The soft tissue viability governs the choice of an implant at the time of revision. The selection ranges from the cruciate-retaining to the rotating/fixed hinge implants. The surgeon needs to plan preoperatively, but usually, the final decisions are made intraoperative. As determining the amount of constraint necessary can be challenging, we have tried to lay down a few pointers, which would help to make that choice. The posterior stabilized implants can manage most revision knees; in certain situations where they cannot accommodate the flexion-extension gap imbalance, a varus-valgus constrained implant should be used. The rotating hinge implants are used for severe instabilities or loss of soft tissue or bone around the knee. The use of a higher constraint implant has its consequences like reduced life span and reduced function. Thus it is crucial to use the least amount of constraint as necessary - however, as much as required.

Factors Influencing the Valgus Cut Angle-during Total Knee Arthroplasty-in Indian Population.

The number of total knee arthroplasties performed in India and the world is increasing exponentially. The valgus cut angle (VCA) of the distal femur decides the final alignment achieved in the coronal plane. Little data are available regarding the ideal value for an Indian population and there is little consensus whether to use a single value for all knees or to individualize the angle for each patient. The parameters that can influence the value of this angle have not been evaluated thoroughly.Standard long leg X-ray (orthoscanogram) was used to calculate the VCA in 302 lower limbs (160 patients). Only Indian patients were included in the study; knees with bowed femurs were excluded. VCA, femoral length, medial hip offset, neck shaft angle, and hip knee ankle angle were measured manually. Demographic data such as gender, height, and weight were extracted from hospital charts. The correlation of VCA with the various parameters was evaluated using Pearson's correlation and its significance assessed using the independent Student's 't' test.The average VCA was 7.4 degrees (range: 4-11 degrees). Age, gender, height, hip knee ankle angle (alignment) and body mass index (BMI) had no influence on the VCA. The neck shaft angle (r = -0.520, p = < 0.0001) and hip medial offset (r = 0.223, p = < 0.0001) were the only two parameters significantly and independently influencing the value of VCA. There is a wide variation in the value of VCA in the Indian population. Choosing a fixed VCA will lead to significant number of knees aligned outside the ideal 0- to 3-degree hip knee ankle angle. The neck shaft angle and the medial hip offset are the only two factors that influence the VCA. The patients' height, preoperative deformity, gender, and BMI had no influence on the VCA.

A prospective comparative study of local infiltration versus adductor block versus combined use of the two techniques following knee arthroplasty.

BACKGROUND: Pain management after total knee arthroplasty (TKA) is important as acute postoperative pain can affect patient's ability to walk and participate in rehabilitation required for good functional outcome. This is achieved by effective intra-operative and post-operative analgesia to facilitate early recovery. Adductor canal block (ACB) and local infiltration analgesia (LIA) are analgesic regimens and commonly used for effective post-operative analgesia after TKA. Our aim was to compare the efficacy and outcomes of these two methods, combined and independently. METHODS: Our study included 120 patients undergoing unilateral TKA, who were randomized into three groups: LIA (Group I), ACB (Group II) and combined LIA + ACB (Group III). Patients were operated by a single surgeon. The outcome was defined by post-operative analgesia achieved by the three techniques (measured by the NPRS) and amount of fentanyl consumed postoperatively. Secondary outcome was evaluated based on postoperative functional outcomes in terms of ability to stand, distance covered, range of motion of knee on the 1st post-operative day, complications and WOMAC (Western Ontario & McMaster Universities Osteoarthritis Index) scores. RESULTS: All patients were available for analysis. Numerical Pain Rating Scale for pain showed significant differences at 24 h between Group I and Group II, with a p value of 0.018 (GroupI was better), significant differences were found at 24 h between Group III and Group II, with p values being 0.023 and 0.004 (GroupIII was better). No significant differences were found between Group I and Group III at 24 h. Total fentanyl consumption was significantly less in Group III than in Group I and Group II, with p value being 0.042 and 0.005, respectively (Group III was better and consumed less fentanyl). No significant differences were found in WOMAC scores between the three groups at baseline, 2 and 6 weeks after operation. CONCLUSION: In patients undergoing TKA, analgesic effect of combined ACB and LIA was superior, as indicated by reduced opioid consumption and no differences in functional outcomes and complications were observed as compared to separate use of the two techniques.

Impact of Charlson indices and comorbid conditions on complication risk in bilateral simultaneous total knee arthroplasty.

BACKGROUND: The purpose of this study was to evaluate the influence of Charlson indices and comorbid conditions on the risk of perioperative complications in bilateral simultaneous total knee arthroplasty (BSTKA). METHODS: In our retrospective analysis, 556 patients including 133 males and 423 females (mean age 65.8years), who had undergone bilateral simultaneous total knee arthroplasty between 2011 and 2014 were included. Risk factors (Charlson comorbidity index (CCI), age-adjusted Charlson comorbidity index (ACCI), and comorbid illnesses) and perioperative complications were noted, and subsequently, statistical tests were applied. RESULTS: There was significant association between Charlson indices and most of the complications (P<0.05) with high-risk ACCI groups (a score>5) bearing maximum odds for cumulative major complication (OR 4.165, P<0.001, 95% CI 1.874 to 9.256). In addition, hypertension, non-ischemic cardiac illness, and moderate to severe chronic kidney disease proved be to be determinants for major complications (P=0.031, P=0.041, and P=0.014, respectively). We also found significant associations between organ-specific illnesses and complications such as cardiac, pulmonary, neurological and renal complications (P<0.05). CONCLUSIONS: Both CCI and ACCI are predictors of post-operative complications with ACCI being the better predictive determinant. Hence, these predictors should be used for risk stratification prior to patient selection for BSTKA. The influence of hypertension, non-ischemic cardiac illness and moderate to severe chronic kidney disease should also be considered during patient selection. Moreover, optimum organ function at the time of surgery should be a priority to avoid these complications.

Management of distal femoral periprosthetic fractures by distal femoral locking plate: A retrospective study.

BACKGROUND: Management of periprosthetic supracondylar femoral fractures is difficult. Osteoporosis, comminution and bone loss, compromise stability with delayed mobility and poor functional outcomes. Open reduction and internal fixation (ORIF) with anatomic distal femoral (DF) locking plate permits early mobilization. However, this usually necessitates bone grafting (BG). Biological fixation using minimally invasive techniques minimizes periosteal stripping and morbidity. MATERIALS AND METHODS: 31 patients with comminuted periprosthetic DF fractures were reviewed retrospectively from October 2006 to September 2012. All patients underwent fixation using a DF locking compression plate (Synthes). 17 patients underwent ORIF with primary BG, whereas 14 were treated by closed reduction (CR) and internal fixation using biological minimally invasive techniques. Clinical and radiological followup were recorded for an average 36 months. RESULTS: Mean time to union for the entire group was 5.6 months (range 3-9 months). Patients of ORIF group took longer (Mean 6.4 months, range 4.5-9 months) than the CR group (mean 4.6 months, range 3-7 months). Three patients of ORIF and one in CR group had poor results. Mean knee society scores were higher for CR group at 6 months, but nearly identical at 12 months, with similar eventual range of motion. DISCUSSION: Locked plating of comminuted periprosthetic DF fractures permits stable rigid fixation and early mobilization. Fixation using minimally invasive biological techniques minimizes morbidity and may obviate the need for primary BG.

Prosthetic replacement in femoral neck fracture in the elderly: results and review of the literature.

BACKGROUND: Intracapsular fractures of the proximal femur account for a major share of fractures in the elderly. The primary goal of treatment is to return the patient to his or her pre-fracture functional status. There are multiple internal fixation options (screws, dynamic hip screw plate or blade plates) and hemi and total hip arthroplasty. Open reduction and internal fixation has been shown to have a high rate of revision surgery due to nonunion and avascular necrosis. Hip replacement arthroplasty (hemi or total) is a viable treatment option. MATERIALS AND METHODS: Eighty-four elderly patients (age >70 years) with a femoral neck fracture were treated over a five-year period (January 2001 to December 2006). Eighty of the 84 patients underwent some form of hip replacement after appropriate medical and anesthetic fitness. RESULTS: We had good results in all the patients in terms of return to pre-fracture level of activity, independent ambulation and satisfaction with the procedure. Patients over the age of 80 years who underwent bipolar hemiarthroplasty all progressed well without any complication. Patients in their seventies underwent some form of total hip replacement and barring one case of deep infection, two cases of deep vein thrombosis and three cases of dislocation (which were managed conservatively), there were no real complications. CONCLUSION: Hip replacement (hemi or total) is a successful procedure for the elderly population over 70 years with femoral neck fractures. Return to pre-morbid level of activity and independent functions occur very swiftly, avoiding the hazards of prolonged incumbency. We have proposed a treatment algorithm following the results of treatment of this fracture in our series. We have also reviewed the different contemporary treatment options used (conservative treatment, cancellous screw fixation, Dynamic Hip Screw (DHS) fixation, hemi and total hip replacement) used for treatment of an elderly patient with of femoral neck fracture.